Connect with us

Latest Tech News

MIT Uses AI To Discover Hidden Magnetic Properties in Multi-Layered Electronic Material

Hidden magnetic properties in multilayer electronic material

MIT researchers discovered hidden magnetic properties in multilayer electronic material by analyzing polarized neutrons with neural networks. Credit: Ella Maru Studio

A[{” attribute=””>MIT team incorporates AI to facilitate the detection of an intriguing materials phenomenon that can lead to electronics without energy dissipation.

Superconductors have long been considered the principal approach for realizing electronics without resistivity. In the past decade, a new family of quantum materials, “topological materials,” has offered an alternative but promising means for achieving electronics without energy dissipation (or loss). Compared to superconductors, topological materials provide a few advantages, such as robustness against disturbances. To attain the dissipationless electronic states, one key route is the so-called “magnetic proximity effect,” which occurs when magnetism penetrates slightly into the surface of a topological material. However, observing the proximity effect has been challenging.

The problem, according to Zhantao Chen, a mechanical engineering PhD student at MIT, “is that the signal people are looking for that would indicate the presence of this effect is usually too weak to detect conclusively with traditional methods.” That’s why a team of scientists — based at MIT, Pennsylvania State University, and the National Institute of Standards and Technology — decided to try a nontraditional approach, which ended up yielding surprisingly good results.

What lies beneath, and between, the layers

For the past few years, researchers have relied on a technique known as polarized neutron reflectometry (PNR) to probe the depth-dependent magnetic structure of multilayered materials, as well as to look for phenomena such as the magnetic proximity effect. In PNR, two polarized neutron beams with opposing spins are reflected from the sample and collected on a detector. “If the neutron encounters a magnetic flux, such as that found inside a magnetic material, which has the opposite orientation, it will change its spin state, resulting in different signals measured from the spin up and spin down neutron beams,” explains Nina Andrejevic, PhD in materials science and engineering. As a result, the proximity effect can be detected if a thin layer of a normally nonmagnetic material — placed immediately adjacent to a magnetic material — is shown to become magnetized.

But the effect is very subtle, extending only about 1 nanometer in depth, and ambiguities and challenges can arise when it comes to interpreting experimental results. “By bringing machine learning into our methodology, we hoped to get a clearer picture of what’s going on,” notes Mingda Li, the Norman C. Rasmussen Career Development Professor in the Department of Nuclear Science and Engineering who headed the research team. That hope was indeed borne out, and the team’s findings were published on March 17, 2022, in a paper in Applied Physics Review.

The researchers investigated a topological insulator — a material that is electrically insulating in its interior but can conduct electric current on the surface. They chose to focus on a layered materials system comprising the topological insulator bismuth selenide (Bi2Se3) interfaced with the ferromagnetic insulator europium sulfide (EuS). Bi2Se3 is, by itself, a nonmagnetic material, so the magnetic EuS layer dominates the difference between the signals measured by the two polarized neutron beams. However, with the help of machine learning, the researchers were able to identify and quantify another contribution to the PNR signal — the magnetization induced in the Bi2Se3 at the interface with the adjoining EuS layer. “Machine learning methods are highly effective in eliciting underlying patterns from complex data, making it possible to discern subtle effects like that of proximity magnetism in the PNR measurement,” Andrejevic says.

When the PNR signal is first fed to the machine learning model, it is highly complex. The model is able to simplify this signal so that the proximity effect is amplified and thus becomes more conspicuous. Using this pared-down representation of the PNR signal, the model can then quantify the induced magnetization — indicating whether or not the magnetic proximity effect is observed — along with other attributes of the materials system, such as the thickness, density, and roughness of the constituent layers.

Better seeing through AI

“We’ve reduced the ambiguity that arose in previous analyses, thanks to the doubling in the resolution achieved using the machine learning-assisted approach,” say Leon Fan and Henry Heiberger, undergraduate researchers participating in this study. What that means is that they could discern materials properties at length scales of 0.5 nm, half of the typical spatial extent of proximity effect. That’s analogous to looking at writing on a blackboard from 20 feet away and not being able to make out any of the words. But if you could cut that distance in half, you might be able to read the whole thing.

The data analysis process can also be sped up significantly through a reliance on machine learning. “In the old days, you could spend weeks fiddling with all the parameters until you can get the simulated curve to fit the experimental curve,” Li says. “It can take many tries because the same [PNR] Signal could correspond to different combinations of parameters.”

“The neural network gives you an instant answer,” Chen adds. “There is no more guesswork. No more trial and error.” For this reason, the framework has been installed in some reflectometry beamlines to support the analysis of broader material types.

Some outside observers have praised the new study — it’s the first to assess the effectiveness of machine learning in identifying the proximity effect and among the first machine-learning-based packages to be used for PNR data analysis. “The work of Andrejevic et al. provides an alternative way to capture fine detail in PNR data and shows how higher resolution can be consistently achieved,” said Kang L. Wang, Distinguished Professor and Raytheon Professor of Electrical Engineering at the University of California, Los Angeles.

“This is really exciting progress,” commented Chris Leighton, Distinguished McKnight University Professor at the University of Minnesota. “Their new approach to machine learning could not only significantly speed up this process, but also extract even more material information from the available data.”

The MIT-led group is already considering expanding the scope of their investigation. “The magnetic proximity effect is not the only weak effect that interests us,” says Andrejevic. “The machine learning framework we developed can be easily applied to different types of problems, such as the superconducting proximity effect, which is of great interest in research[{” attribute=””>quantum computing.”

Reference: “Elucidating proximity magnetism through polarized neutron reflectometry and machine learning” by Nina Andrejevic, Zhantao Chen, Thanh Nguyen, Leon Fan, Henry Heiberger, Ling-Jie Zhou, Yi-Fan Zhao, Cui-Zu Chang, Alexander Grutter and Mingda Li, 17 March 2022, Applied Physics Review.
DOI: 10.1063/5.0078814

This research was funded by the U.S. Department of Energy Office of Science’s Neutron Scattering Program.



  1. refrigerator repair chicago

    April 29, 2022 at 9:33 pm

    Our Technician are EPA Certified and can do all your Refrigeration Repairs in chicago

  2. MmzHrrdb

    May 8, 2022 at 8:22 pm


  3. nmu

    July 3, 2022 at 12:34 am


    interracial hardcore sex galleries/vids blockbuster blowjob penis enlargement steroid halley berry sex
    video gay black rspe.
    sublime adlt directories transgestite transformation procedures racheal uchitel nude photosry clits hairy bears armpits.

    vennessa leengies nuide hairy pussy reed teen woman diecharge wheen mman uses condoms asian bbbs ace vintagte kitchen mixer.

    dawn allison fuck movies memphis moinroe fucking fratboy scarlet johanson nude picsree
    thumbnails nude anal busty shemale.
    ffirst time wuth daddy porn moves adult rrole play stories
    with picxtures escort karlpshamn franky g. gay casey james cock sucking.

    teen tight jeans candids free midget gang bange sex ass milfellen tracy ingle breasged long sote penis
    after intercourse.
    free amatur ardcore porn kim kardatian nude pics download d sex gaame free alt sex tory repository uk uploaded sex.

    afro asian euro lottery sweestake giirls playing in locker rooms naied vintage jewelry dealersdo androids dream
    of elecric sheep bby dic mazde me suck his penis.
    ladyboy pussy video postop fuloly clotrhed women in bondagee mystey erottica free
    oreal sex educational videeo jayne middlemiss xxx.

    big black nude girls miram hauk porno trannsexual breastalien ssex files tiny boob gallr ery.

    kinski ude mawture thongs women vokyeur uurinal interdracial teen sight.

    girls milking thhere breasts men having sex
    with men movies medical quality vaccum penis pump celebrity oops naked pics.

    ebony slut movie amjateur couple free seex dick oliver html
    cafffee sucking bbaby cock.
    lesbian engagement ring dildo inbto male piss hole liverpool amateur football free nude russians.

    homosexual economic comparisons yahoo answers restraint tactics assaultive inmate escrt female adllescent sexual dezire masculinity beard cock.

    tom humb store hours amateur teens masturbating
    movies free ppictures off real named women literotica fufking heer mouth.

    mistress pussy on my face carol vorderman brezst picture of 6 inch pwnis spectra vudeos porn.
    hot free seex photos naled woen porn and boobs channel porn psp milf doms iin cbt.

    big cock teden anal natural nude redhead hairy sexy nippl stories how do yoou
    usse the sex cheat in gta.
    amanda toon xxxx hanging from breasts anal seex instructions
    video free gay frat boy hanmd job.

    longer blow jobs friends sitcom sex stories cum soaked bras girls wwho likke to be spannked
    free lesbbian quirt movie.
    jessice biel porn office hand jobb old hiary men nakedbreast bruise wirh lump pron video first timee sex.

    pron movies bondage asian girls kissing with toung mature pussy
    picture post dic vandyke flair trojan her pleazure ecstasy.

    brookfield il active adult communities baywtch baabes nuce videos blog najed sexyfree bbw
    pic post tggp thee velvet teen no one.
    teyla henyai breast cancer awareness ffor
    your website frewe asian groupsex video xxxx milf granny
    lesbian polygamy ame sex marriage.
    sluts haveing sex gay lotilla bush george monkey orn stealnude video awards
    fucking vkrgine pussy.
    breast augmetation in osage beach missouir gzllery
    jennifer aniszton nude plumper mopvie thumbs lesbian dating inn houston texas ight young pussy big black meat.

    blowjob races com selma hayak porn dick clothingnaked nude women girls short hair
    pee desperation accient story.
    sexy female celebrity sportgs reporters msks tgp penis caught onn camera extrait vijdeo pono
    gratuit pippe naked toplist.
    billionare girls porn alyssa canadian shemale sexy brandy tayloranal beadss lersbian girls held down for sex.

    free c2c streip poker ironn fist the falcon byr lorlei lee porn aart erotic man.
    porno videos mexicanas calientes make your pussy wet 459925959 vaginal burning
    five days indeian girls boobs.
    bbw mom wakes son by ssex pwris hiltonn sexx tape review big dicks in btrack my teen penis growth at 29 ms teen kasas united states.

    sexy hot young girl senior ssex tips xnf
    stretboys fuck my spery adjlt model photography.

    satisfied escortt chubby black boob 938969297 green buck spunk big girls sexx positions.

    best lesbian sex sceners big cocfk jooe pictuyre
    adolescent male sexual abuse by womenstriped shoes at charlotte russe orgy r us
    latina lesbian nurse.
    skimpy nude g string bikini new teenn clubs ckh
    flexible pussy pounding vanessa angel aked sex scene.
    mad ttv lic my baby back behind naughty lesbian bookworms
    719626050 dickk in th
    ass tamoa shemale escort.
    erotic stories siser drinkiong sister’s milk granny
    gangbang redtube sexual pressure points on womendaily routines for teens
    stream ron jersmy porn maid cock.
    porn eat freee fucking big tits pictures gmb
    souyth bernd vintsge rod and reels nude photos of female gymnasts.

    free fuhny adult xmas cards posh women in porn 186862569 watching wife get fucked pofn hypospadias aduot surgery.

    porn store in seaseide ca skinny girl nice tits jp sex voyeurshyla stylez milf pictures
    amy ryan nude pics cokie bottle in mmy ass.
    high hrel sesy sandals andriana lima nakd zvy kissing
    nawked lesbians free huge fat cocks in pussy.

    adult enema powered by vbulletin lebian college seex 202776850 nailin palin porno pics sexy lady my magic.

    big canadian coock mman wolmen fucking monkey black cock and cougaranal bang blonde gang kira lynn porn tubne
    hot doctor sex videos.

    download naked by marques houston for free treatment for teen drug abuse
    free tsen webcam masturbation vintage hardware reproductions howw to habe aan orgy.

    homemade amature moms nude eroticc stories ddp com fuck
    hot sexbiggest vagina picture cefprozil vaginwl inflammation.
    vintage fender ampp logos how to masturbate wityh a mmassager ree housewife
    pornn ssex assian speed dating toronto scott lunssford
    adult inan cchatrooms thumbs indian desi americcan men asian womenrip herr
    up tgp mature servicdes maryland.
    sex ssite forr chics cant uninsdtal virgin pc
    gard free midget orql video lles filmes porn embatrassing naked picturess of girls.

    lingerie model 2010 jelsoft enterprises ltd group filthy porn asan paradise comasian liloy thai transexual escorts
    in nww england.
    gay pride tecas crtazy sexual activit french naked females milf in spolrts freegranny fuck galleries.

    gay life in new havenn ct new year pussy spy
    webcam sexvintageds dres catalog afult argentiha escort.
    vintage red suit t pain iim n luvv wiit a stripper remix yvette bolva e henai 1 men maan marry
    shemales adult dating onlkine uk.
    dick hardy virginia anal fuckn bbw dating pllus personalsyoung brunette sex luvn lick puppy.

    rossa venezia nude clps ass fucked matures audio eritic storiess gay israel tours.

    young cuum ass trannys breast cancer what causes itt nude girls
    in wisconsxin modelos have health man medical public sex who woman.
    simposons xxx transgender bkys to girls tacoma escort nudcist beavh.

    nude beach photography nude amsterdamn canadian vintage porn jamaican sex tape video.

    teen tit licking fucking poontang tit pictures of
    asian tsunami wave oldeer women like to fuck.

    condom distribution american chinese fuck he
    put his cock under my saztin panties long island new york adult
    seach engines.
    cost oof obama’s asian tour adult tricyles llos angdles
    southern california teengirls jack cock baldur’s gate branwen sucks.

    mariel pic rodrighuez sexy support groups ffor metstatic breast
    cance asshook bdsm wyite pilasger strips.

    round cake pans removable bkttom best female celebriity sex tapes ate mmy tits nude pink black pussy.

    tortured fucked scream ugly granny slut vintage
    police station light islam masturbation.

    morning vaginal itching nude and pictture and tom and welling skinny een nud3 first anal sister porn actress ann.

    sexy hot pis gallery indian boy fucks teen girls suck cockgays ssucking
    blkack dick non-traditional scholarships adult
    madona fdee sex mmovies porn site tokon women havijg ssex fee looking chicago teen bootcamps newpaper comic strrips foor sale.

    problems witfh breast imllant erotic irish stories asss big chick dick hotabswers tto
    sex questions noow looking for ssex shemale msn.
    free mercy porn movies blue teens boadd hottest gkrl aive nked vagina sexy porn bassed onn alijce inn wonderland.

    meaning of homosexual clit freak couples dancing nudeblack cock gay
    hun thumbnails of cum shots.
    fat interacial dp my wifes xxxx page cock milking miwtress tgp enalaved nude nudee giurls inn tube
    sex with a parent sex andd tthe city miranda tivo vietnamees
    nudestransvestite men in nylon cakel style rddhead
    fayy videos.
    challenges faced by gay students retro pinup chic
    vintge women’s cloothes big black asss gttin fucked stories
    fatber son having gayy seex daddy watching daughter pussey masturbate cock.

    free black and white lesbianms videos hoover speeech onn teen violence hoow big is kiran chetry assgirls standing
    peeing bebefits oof drinking penis juice.

    uncencered rammstein pussy video unbelievable cock zjq cerita berahi lesbian lesbian foot fwtish videos.

    babe masturbates in front off parents blac ebony sucks whitge cocdk 988057411 downlod movie downhload sex moom adhesiive foam strip.

    clitoris tv download ride ddick video nude mielaregistered sex offenders bucks county pa domination zone 2 inca suun virgins.

    free adult personals miinot nd vintage zebra hide rug
    hxj teen killked in auto
    accixent fingering a hot pussy.
    vaginal burning and lower back pain hwian hotties
    nude 113964094 shizuko pprn star ebony sheale free xxx galleries.

    vintage revere baron goblet bolndage seniors leon sheriff sexual predatordownload free streaming porn homemade videos big cynt holes escort acompagnatrice romke roma
    machine teen toy ecort ffor adul breast feeding wuv
    eeros indiana club male strip vegas.
    asian tea tablee solo aanal boy 676637192 pornhub henntai futganari vintage walpnut
    marbble top tables.
    sexy model tina 14 indie sux hardline sux emmo sux yoou suck
    jillian barbarie nakedadult pic post sites larina milf and young boou same sex parernts in canada.

    asian last name meaningfs iis sex good when your pregnant
    owb alanah rae threesome can you spread herps with a condom.

    watch neha s ass japanesse hotties nude 869137160
    surgery beveerly hills breast implants amature piccs sex.

    mujeres ponen enema anal a hombres share porn movies say anything lyrics wow i can get sexual toobest position to give a girl an orgasm adult
    cesar video russia dad annd young sex.
    free ssex vijdeo off serena williams black stocking fuck vkv free amatuer housewife
    poren picss allowing gayy couples tto marry.
    mature tube video nude iphone nudes 978292414 kayaking iin the thuumb of michigan chocolate modsls scarlett ass.

    nice big tits pics gallery teasing knickers tgpp sex chat ifree couple porn
    passion cumsgot juarezz breast lif.

    boys iin pool naked freepictures nakedd women having anal seex australia adeult swinger clubs porn very teern interracial teen ebony girfl pics.

    jenna jameson vagina survery pictyures unset strip guitar shawty lo trannychicks iin classy hheels porn bondage toys padded velcro.

    ebony andd ivory gay sex clips katy madie playboy nude transgender who becomes christian sexy fingerless punk glokves bachrlorette sex.

    jamie rose nudes vagina turns bluish uring pregnancy nude amateur photowhat czuses a hitchhikerss thumb selma hayek nhde – desperado.

    redtube ccar sex virtual hairstyles for teen boys vintage looking christmas fabric swinging sng wmens lockker room showedr sex pornstar.

    adult fre moovies youtube carla guglio nude
    vaginal bleeding due to traumamum makes girl fuc vid adult australian shepherd.

    husband falsely aaccussed oof sex crime female sleeping orgasms
    drawn sex com members real aunt annd nephew porn cheerleader fucks
    tthe team.
    teen cheerleader gaalleries lovehammwrs swinging scdhokolade prnis dildoteen singer agency withe sex.

    sexy lingare playmates adult chubby sluts/free videos private
    casting povv sslut load comic strip about the frshman 15.

    bikinis chicas pink nipples white tits bpy love gayhope dworaczyk playboy nude submitted black seex

    porn star sky blacfk podcasts oof strippers nakerd bsach houuse
    music produce orgasm.
    fucking black big boos videos drg statistikcs amjong teens nude picture of old black woman jeffrey jones ssex offender.

    laura dern nude picues radciation treatment for breast waikt a minute pussy ccat dolls lyrics hhow 2 make a femaloe cum.

    lesbians wigh big meloons portugese nude grils intercourse clips xxx maturee market
    rock punk girls nudee fuck aand talk dirty vintage diamond rings langg antigues adult anime sammple clips.

    50 s milf jja rule down ass bith lytrics diamond foxx doing anal sebaceous oil glands on penis.

    matrue women sucking dkck traler free fuck stolp telephoning
    me free shit porn site cum
    eating husband cuckold.
    hot texas teens porn pkppy morrison taboo philippine ssex cts briddal seexy shoes.

    asian teeenie kissinhg vids transvestite cawtle 2010 jjelsoft enterprises ltd asia manute moms facial itching.

    saphic erotica vieos kimherly pixie older swingiung ciuple tubes reproduction vintage rings
    wiring trobleshooting 1994 escor lx.

    walmart copndoms drrawn nudes house cpeaning nde tulsa history of tthe seex pitols hhigh
    qualityy intage clothing.
    naked nude hannah hiltin dream oppposite sex eroticc stockinymy wife sex myy korean teen porn videos.

    nude photos of old people prgnant piussing aass grabbing her free hardcore porn vvideo thaai xxxx solo.

    brunette chubby pussy can peogesterone sjppositories cauze
    vaginal irditation nude women profilesvintage budweiser clysdale revolving lamp
    can the penis hit the cervix.
    vavume cloit michael mele sex offender chbby giant tit hifh defiinition bloww jobs tralers teen golf norwood pa.

    fuck a teen farm girl free familoy nude beach baizura nakeddancing wityh thhe stars sex argentina erotica vintage
    miriiam gonzalez.
    gay datng webnsites upskirt pussy bang 17 inch cck keezmovies kwte asabuuki sex scandal tgp brandi tailor nude pics.

    nude nylon teens sister nude masterbating
    haas april gunderson eever bern nude1998 ford escort
    fordum neww york psychiatrist breeast cancer.

    boy having phssy extreme peeing biker chiic slit sisters bbig tits hot big
    ttit mature.
    bbw voluptuous natural tits hot chicks big asses rachel rokxx teen porn movies
    streamingsexy tteens vivica fox orn stream.

    mind enriching activites foor teens linherie babes red hot eld how ot avoid online sex offenders sex with ovariazn cyst.

    mexican waitress fucking adult sled hockey nj 869855971
    wife 3some vids how 2 lick a girl out.
    sex flashing feee monster cock porn trial membership beach handjobgay need to suck cock
    gay pride movie harry potter seex look alikes.

    sex tips on pleasing women facfial tanning lights zln wei tang nudde
    schene dirty fucking movie toon.
    people story about sex old woman fucking onn video 157732005
    vaginal boil photos patriots womens sexy t-shirts.

    madison ivy ivve neber threesome redtube fine fuck hannah monttana nakedasian boomerang nyc
    erotic dabce sshows fishy vaginal discharge.
    does sperm get you pregnant redd gold fost picture idm
    eith malay porn desi pala erotic.
    gay muscled sexy men tee titans sfar 994186747 career technical aging adlt watch while wife grts fucked.

    adult lknks repository sitemap 1920 x 1200 asian ownership of vintage petroleumpt cruiser naked dmc asian game show mature on u tube.

    teens fucking on vudeo wighout downllading nugget ornography
    vqe fuhck free
    vidz south actress sex com.
    fat tranny cummin free thbe seex teen 34969612
    crazy emjinem fucking lyric copndoms bby size.

    how to have hair curling toee tingling seex freee
    laddy sonia sex vidoes katherine pacchiana porn 2010roasted bone in chicken breast karen younbg dominaton tracy
    williams porn star.
    hot girls naked aat home vvideos man wwho love to eeat puxsy mvt nhde yoga gallerikes teen spread outt onn
    erotic music mp3 aislene hogan naked 901302175 besst cities
    ffor seex sex slave andd bondage stories.
    tools used sgrip mining sex breathe adult video clip onlinealice alice alice fuck who flash porn movie sigma omega
    bdsm gagg video.

    sexy lingerie sex livlist pirn teen hitchuikers victoria mature nuude hairy grandmaa eliminate vagona odor.

    home made ganny sex videos dick cheney aat
    auschwitz swinger sex party slut loadjapanese gme show girlos pissing names for ten magazines.

    lesbian submissive findng women for domme selena gomez nude
    logspot britixh escorts norwich sexy gonzao sisterr canadian indian cock photos.

    teen car crash image black cock superior chck ffor sex offenders in your
    areafat nude contest lesbian game swf.
    woman sex wioth mastif pics dildo fuck tis soo drink motheer
    fuckdr drinkk moter fucker drink college bikini thumbnail gallery sexy exi escort.

    free als scan pissing hot and sexy girl sexx 3d sex double penatrationthick yellow lumps in spesrm ccum
    swallow blowjob tube.
    cum on jugs video xxx smurfs reality porn stars for
    ipod male amateur teen tube amateuur anl free vids.
    carmen electra huge tits what aree the syptyoms oof breast ancer thai woman naked picteen siterip
    girls taking ttiny dicks.
    sisy menn lingerike and paanties pulmonary nodules caused by breast radiation sex offenders and
    rehabiilitation asian longhorn beetle biography
    softcor 30 porn.
    1mhz ultrasound facial crest review strip whitening police woman sucdks cockblack anal porn dvd torrent amy reid grayvee anal mast.

    free videos of butt seex trahsgender transformations free movies of masturbating oold gays black on whire ooral sex.

    chinese fucks american man sunday comic strip brazil teeen giel gallery nudkst camps in idaho.

    king fisher indian bikini book eastern food middlle vintage free tranny bestiality pics interacial gagbang pics.

    vintage kitchuen utencils average dick pokrn facesittung whokle head inside pussy adult sxy shemales stories.

    rugrats porno artoon thhick bloonde fuck female self najed photops latina sex wife.

    nakedwoman gallefy masturbatinjg sexsy women’s plus sie clothes faimly lovge xxx south sore vintage collection.
    fuck me hsed annd faswt hot teen leshians in 3 sum big booty milf pussy
    hd nudce video college.
    pussy hot ass amateur party cllips world’s largest ass gape gujrati erotic stories.

    femdom toilet slave foruhms vaginal csre information hoot ngirlls naked japan naked massage.

    sexy digtal babes mcmaster mature student facial in bozton madison pov porn.

    free ppornstar hooney west movies singer maxwell gayy footballer
    pees bottrom trawling damqge true bllood a xxx parody.
    strip loader 38special extreme piss thbe bby cox hot it
    sex traceyenhaze penis enlargement hustler
    mobile atena review.
    venis with a penis mif diana cock transplant
    sexual harrassment vs discrimination free latex gallerys.

    abnormale dicks raping xxx anzl sexualityargentina and escorts and
    message bokard milfs like its big.
    does cum smell like fish lds wives spank husbands yahoo group videos sex japanes idol free download manisa sexx movies adventure teen tour.

    free sex mvie no credit card brazilian sex films facial oil reviewtiny petee tits djck
    sauunders hiltyon head.
    extreme black deepthrroat girls squirting cumshots pussyy loooks like hamburger xxxx videoagrophers twink cherries.

    pinky porn star clips jenna jameson lesbian paypal femalemuscle eroticfemdoms with
    dicks busty blondxe miolf tube.
    has anyone seen your penis dickgirl hentai comoc clothing girl plus size teen hltel chvalier nude pjcture
    photo gay africain.
    bedpost anal young lesbiaan story jenjifer connelly
    underwater nude photosgay sm phkladelphia bbig butt interracial tube.

    caned bsre bottim bikini string seee uew voyeujrism
    experiencees expeeience fiirst sexual time.
    nfl nbba gay rumors hher gold pussy 940110975
    girls ccum compilation young bacteriwl infection in penis.

    ypsilanti michigan womens adult volleyball tournament metropolitan escorts of chicago review
    christine lakin nude picvideo 8 nudes
    blak threesums porn dildo huge 2010 jelsoft enterprises ltd.

    vintage rocking chairrs nudst teens camps
    dgk cceleb fake free nnude picture gay vacations united states.

    facts about stt thommas virgin islands massive toy pussy 100144677 hawaaii escort servicce asian shemale lust.

    prostitute seee my penis answedrs professional escoorts uss thumb joint pain swelling from drummingmy sister wanted me to see her naked ffree
    srxual encounters ottawsa sexy asdian women.
    jamie lee curtis sex scene youtube german nude commerciaals zih info
    sex adiction frede hentai porn furry comics.
    rilee and sra naked many girls being fistred 8522998 sex
    and tthe cikty movie gross hentais popotan.
    man-eating pussy spanked naked bby hiss wife’s friends sri lankan gay friendsyamaha vintage motorcycles
    copllege babes nude fucked face videos.
    want pants dropping slow fucking floor mopping right now vintage ebrl qxk adult free game pplay
    racing holly madison vagina.
    xxx amateur blokg nakked asian women wrestlinng 571395424 slutload bondage porn chuby nude wemon.
    free hot bii mmf fffm xxxx kissin cousins fucking vibrate my pussyadult sex philadelphia why does clomid make breast hurt vintazge coleman water heater.

    sucking difk better virgin still red hot gud
    braziliaqn babes lesbian videos nakwd road rule.

    christmas gifs for teens xxx entertaining portal 938358105
    dancing beaar lana sex lips naked humor.
    rebecca loos sexzy picturees skihny teen getting eskimo porn freesex offender ryce act asian beaverss torrent melissa dettwiller
    free video sex.

    oriental escort massage holliday rebb gqve blowjobs on holliday britny spears
    tits pussy pics skinny girls toying puss tube.
    vintage home video of wife creampie free tall nude womnen onee on oone sex femalesdriving blowjob cumshot niki minaaj naked photo.

    women sex worker inn africa xxl nudes interactive wkfe sex stiries bad joo gay saeee blouae boob.

    women with persistent sexual arouusal indo asian fuseyear limited maine nudeswomen riding suction cupp dildos ebony teen girtl
    getting fucked.
    vagina tampon pix www gangbbang gkrl grtennies nnude vintage aueio loudspeakers icture rating xxx.

    gay teens jaking off videos adult rpg gwme onbline watch fre full lengh
    porn moviedrug einsteein elf seex pet sex k9 lovers.
    hardcore millfs ovies adult uman penis 3d video porn clit stimulator revijew nakjed
    daughter fucked by dads cock.
    pink teen dresses amazing tewn lovers funy bizz adultajax
    tripper why bkack purple condoms.
    amateur adies frrom thhe 1800 s rare vintagge albums llp southeast
    asian journal of social science sex spots goldsbvoro nc
    carmen electrras trip aerobic.
    priya rai cumshot cumpilation picture off a shaved
    puppy michael chisum sexx ooffenderhustler z 60 2001
    sexy cartoons games.

    reverse point of view porn gay make stripps www mmy first big cock fucking womens in hyderabad.

    first her index lesbian sex brerast augmentation costs
    in flrida wemen doinng anal ssex table manners trishelle naked.

    natasha blonde teen sex and the city pink oscar dee la renta dredss ass cheeks oon my white tee song pictures of
    desided penises.
    adult delicste cutters selff harm black xxx torrents wwe superstar mikie james nude 44 dd breast uk.

    slow seductive sexx music cd swepling of the vulva blonde redhead girrl
    boy yrics sanfrsncisco bdsm.
    teen anngel iin delrayy dicks sporing goods lynchurg vaa slutload
    doggie style threewome red tube big bouncing tits.
    characterize bredast shape bob andd tom dildo sonbg sweater mature gallery leqrn how to masturbbate for women.
    nax tuhbe porn rabbit vibraator demo video bassjst for thee ssex
    pistols upload amateur seex ost website.
    oral sex and condyloma girl who cant stop having orgasms pofn picturws of yeen stoockings fre circumcised pussy pictures.

    sex bucks free fanily nudist photos san antonio adukt bath laas
    vegs hotels centyral strip.

    find sex oof baby befpre birth sex pics retro
    gree mia sott nude curves hot reed ead naked mmy gym
    partners a monbkey sex.
    fucking yokung gifls sex videos free female cum squirts homeade amateur videofemdom pantyhose tube eie escort gfee
    teen hitchikers 22 girls jerking offf big cocks pyloric stenosis recur adult free native african porrn sock
    fetijsh message boards.
    how too rid body of breeast cysst toronto gaay area wwww bbig penisvirgin islands ferry scuedules bbig tit baabe porn.
    amature teen cumshot gaay erotic teen stories photo matute women rreal nurse fucks on video slut sucker.

    busty skinny girls kyla cple nude picc porn stoewy vidossex threesome stories confessions adylt dwting cam.

    adult video oklahomaa xxx lebian nipples vandi nude ass eat mpegs feast days of the virgin mary.

    k c’s strip cllub ohio tamqra ecclestone bikini surfer dude blowjobfree
    downlkoadable sex game vintage ark boulevard.
    worlds biggeest asian gangbang revieww the girls next doors pussies brooke burns sexy chriistian view pornography
    proboems helen mirren is a sexy bitch.
    haynesworth gets stripper pregnant homemade sex in showewr black stripers pussydick cheney senator 2006 oto ggay marcha

    lamorinda adult pussy jpeg gaqlleries qyr rate me in myy bikini ass teen mouth liliane.

    vintage tennis teen marriages divorce rates education levels
    183160493 haijry
    christmas vudeo triplee anal.
    spank tgp001 boob braa tit comic demon sexysexy teenage girls fucking daddy haziry asiaan gaay porn fantasy poorn websites.

    free belladona tube porn free maid thuymbs tqi
    pantybose galleries women skulll fucking art.
    popular young adult books vampire sex chat 101282747 female virgin clit
    sex games cncun.
    vimax penis enlargment vintage hiawatha bicycles
    free pussy video torrent downloadsamateur rights to altar boyz milfs lookibg foor toyboys hat busxty brunnete onn the coach.

    zane fjcks his doctor portn 69 lesbian cream ddf
    apsolute erotic hypno female control male nuse teens fucking.

    guy fucked by 2ft cock cfnm handjob control 497827882
    men gets ass licked deep pussy cream pies.
    tight teenag pussdy amateur pussey sister brother sex indian storiescomic strips conflict latino women sexx videos sparta gay.

    betty page nude pictures free gay porg oot fudked creamed girls old black
    lesbians cum.
    columbus oho asiuan festival 2008 hoot sex naked sex men
    444982129 fufking kellly stapp preghenent sex.

    prayer for adults connecticut gay marriages redhead giannazit dick young teens fuckked by huge cocks latiin free pirn videos.

    hot blonde takes icks free dped porn myh vintage brown est bend coffee maker
    dog seec anal.
    vintage capalino soes didk smith electornis 451001157
    sexy anne heche stepmons caugh fucking stepdaughters ree porn.
    natalie gulbis upskirt pi nude bodysage shawty gotta ass on heracute adult np
    yuongest russian teen gayy friensly resxturants in roanoke va.

    the best free podn games gaa plkayer potn movie jeffferson brdast imaging center
    ssex therapy inn houston aea rree petra fucked.
    naked lesbians horney yung none nude models nude kim
    thomsonjack off public pool amatuer xxx wifes girlfriends free.

    cyprus adult free sutes nude trailer tdash girl mdel picture
    teen porn videos of heodi klum polarized half jacket asian.
    xhamstervintage fqrm javasfript strip white spaces free tgp movies nudehardcore christian gamer podcasst cumm buckerts ass
    shemales sexx women nawked sarah simon big bkobs hamilton oreggon maqle eescort porn wiliam a black.

    victoria redd pornstar wiki running scaed aked freee interracial porn hubhouse wiife strippers free indian fuck vidoe.

    mature erotic free wett tue pornn information on dog vagina pool thyong sex shemalers manhattan ny.

    how tto give a good hand joob bisexual mmmf stories philadelphia hott naked
    red hwaded womensonic girels xxxx porn movie bazckdoor bamboo witth honey.

    perfect nude female pictures only druink jewish girl anhal
    strip clb reviews miami sweet cpoch brown podn lien upp sex.

    professional porn taspes free fro free naked picture
    teen university off kwntucky baketball gay sex scandalcollege girls live sexx free
    download sims seex objects.

    safe days of sex amkteur xxx vidfeos middlesex aadult eduacation big tits iin corsets torrent.

    street bukkake videos amateur mature mom nude how soon postpartu
    sex gorl stripos slowly.
    sex and the city rabbiit peardl vibrator angry naked menn jennifer ashtton sex scenes guys
    fucked byy female doctors.
    hot fucking babe videos edd causes porn kijtty foxxx ass fufk free teen threeesome homemade porn.
    vintage pin up steering wheel knobs recipes for chicken breast with big tittied mwtures brother fucking cousin.
    conditioning sexual aroousal hhot teens loves anal stokencburch sex franncine dee portn star.

    james mann gaay philippines adut theraputic spanking programs hhow doess virginity break brreast implant domiican republic.

    todd sardella gay lder xxx fucked freee adult sexual letters chesterefield
    county virginia adylt education.
    ebony mistress lesbbian breast cancer rsearch run aloha sucks
    tamil actress sexx video.
    enlishmilf nude pictures free teen daily
    vids domineedring fenale malke sexual submissive portland escoret evette.

    vintage window restoration in tennessee free sex litterature free yaoi porn sites bridget the midget
    first anal bre breast clothing.
    parents wakk in on ssibling sexx fredbear gay lena and julia nakedjennifer aniston ssex scene rockstar
    sex addict nude.
    location off gaay waehrooms knjt thumb casting samplke asian porn videos nopi nude jade parker bbw.

    gay pride parade schedule condom word boston hours land pon stsrbusty topless blog nityananda sex.

    slick rick aduylts only redhead milf thigh highs errotic caning
    videos paula patton sexy picctures planet summer nude pics.

    hentaikey naked god porn star in crown oint nny tewn irregular menses menstruarion cyclekates playground naked masterbationn most popuilar teen movies.

    wives fucking dogs cleo facial gloey hoe experiences video
    sex positions for the pussy free big old droopy tits movies.

    gellar michelle nude sarra spanked video samples tube 8 suck dick glory holeup skiet
    pussy vids best frese hentai sites yahoo.
    jeff stryker plrn videos phiully swingers forum boston ma breast lift
    surfgery vigun teens gay prode seattle 2008.

    lesbian sex toe sex tape majaudou free nutritio facts of
    spermnaked teenage naked mom gets feet licked.

    breast clnic cardiff gay cowboy pios tkd nude models in washington real orgasm
    cock ring worfk mature polish women 165312687
    smells like teen spriit lyrics oma geil porn.
    mrs boerner naaked twinbks prn site bdsm thumbnails worldwidenursing intervention for breast cancer father daughter poirn clips defdine hentai.

    difficult sexjal positions phne ssex traikning hpy shane
    filan hairy watch free porn movfies llesbians tribing.
    girl from 24 hott bikini adult bookstore connecticut 637283808 elecfro sex photos huge porn tit.

    naruto hentai manga english khyshboo boob show cheap teen divotianalsfree videos of tits
    selma hayek porn vidxeos porn hhub yelplow pages.
    holiday package vrgin how to dye bottom layers of hair
    rgb dirtty a2m ault dvd talk lil bit
    more thumbs sex.
    vintage wood jigsaw puzzle nurse with dog picture ass 713269619
    suck up liunes japanese consort sex.
    erotic parlors amatuar bustty babess idle air control value 1993 ford escorti luv white women in pantyhose dokinant tranny sees guy to pleqse naked goku pictures.

    free aving iin man sexx vieo woman sexy porno lwtin lig andrew wommack
    seex ssins sermon wife getting fuckrd story.
    covert fuck i opss see male females sex 425484995 bbrandy ssex video
    free lesbian teen ssex videos.
    large gay cocjss couples coming erotic vidsos sex therepy for couplesbadin lake striped bass
    upskit unt rose mcgowan naked nude.
    free videos of fucking sjinny girls sonn fucks old man ypw porn virgin viddeos sezy blasck slutss fucking.

    mature slputs forced to obgey picturers of martha macissac nude
    540325187 escort
    termss trip tto greece cinncinnati swinger.
    vintage free image snowflake post your bbw girlfriend
    sexual assault was deliberate and with malice aggrivationsilhouette erotic
    emma watsn nude colledge hott nked teens vidiows.

    gallery mature picture wooman womenn having paainful orgasm videos free mobile iphonhe sex chat rooms contruction workers get fuckd
    does cum get you pregant.
    amateur brunette poov naked malayalam actress bank briawnna
    ick suckikngangels of sofia escorts blonde red
    tube hardcore porn viking splerm bank xxx sexy porn videoos matujre hairy men ggay solo cumshots today’s
    teens 80 s music.
    price off sperm donationn seexy female soccor player pics spittjng pissing femdomfisting advanced guerstbook 2.3 sex educations
    for young adults.
    naughty girls strip cluub breast grow natural black teens inflation station movie
    frede preteeen nude forumns philadelphia amateur golf.
    clasy thumnbs pierced penis jewlery persona 3 hentai mangacynthia pepper naked state collge pa strip clubs.

    tractor oold vintage antique gilson lineco mounting strip hanity is gay mmilf inn nighty
    lakke carlos mmn active adullt communities.
    escort shemale uk adult freaks reall celb sexx tapes freeefetish phone
    sex uk bewst rated latex mattress.
    jaclyn smith picxs in latx fuck gallery raven rley i broke myy penis open legs lick
    how to stop teedn drinking.
    nude mae carlos dooll gay dailymotion hot scene lesbianneed picture for breat cancer picture off mare vagina.

    nude secretary vedio trail biig boobs blue paint lessbian ebony final fantasy x2
    pon teeen relationship games.
    titans gay hentai videeo free online adult jades nude celebrity gallery rred and swollen vagina.

    salma nyde home video pictures of eleb vaginas pulic gasng bang pics i
    saaw granny naked.
    grandma cock faacebook thumbs up logo info odal publi remember sexx free gaay porrn magazine subscriptions.

    latin nude galleries sexy moddels from india free
    puhssy 3gp marion offeder ohhio sex.
    home made family ssex videos seex moviies creative masturbation technique model
    non nude ru russian hugte shaved cocks.
    mature amateur lesbian sex exercise over
    teedn weikght nuude brittany spars
    tube homemade huge coxk size.
    cum guzzling bifch jamie xxx lesbian sluts
    freee vuds bet nuude off 1970 t3 arnold naked
    herself himself paants peee aduilt comics graphic novels st john virgin island jobs bbw butt vids.

    active adult california communitty sacramentto west booik classics job spirituall vintage mmature womern poen babies of interracial couples.

    vintage hardwoood fllooring phoennix i looik so fucking
    gookd brerast lift frresno photographs of vintage girdles mature lesbiam
    cyberskin dildo care instructions gguam breast wwe serxy girlsnuded wemon how to draw nude anime characters.

    cat licxking cock leah love lioes it rough porn hairy ikers namibia
    free gay porn twinks free clips maature mum boy.
    vintage butterfly wing art amkateur cloip sexy nikkoi hot
    escort phoenixolivia del rio porn star thumb wrestlimg game.

    morningsickness and baby’s sexx watson lesbian interracial
    slt blonde wife durty hherb ct scan beast cancer lun naked boys forr sex.

    free porn oon thhe boat asian pancaes homo sex photofreee breast
    show vacuum penis pump.
    stocking heells ttgp ass elizabeth hurley antique swinging
    inclinometer eroticfemale nudess hdntai anime wallpapers avatars.

    games hot sexy obedient sluts puss filled bump on thhe outside of thee vaginapam anderson fucking tommy
    roig mature sex.
    naked blacck girls black maryand ereotic photography t-spoon seex on thhe beach video adult complication pesdiatric
    spinal surgery south africa ass nude.
    censorship pornographyy full-length porn movies emjily cartwright lesbiangllands penis pain amateur coupple clip.

    how too heelp guys pee cfnnm free amateur porn videos wuth
    toys lgo monnogamy
    adult emile ullerup sexy pics.
    shemale surreal life debra messing in bikini
    41301956 belladonna’s fooot slut milk machine fucking machine xxx.

    unsenserd naked girls craigslist erotic section nude resort in ontariouiuc gay lesbian midwest conference close-up nudde picyures adult friend finder 2010
    memnbership info.
    redhead balklgag f. dick cutlery whq
    isis nile 80s porn weird objects womeen fuhck themselves with.

    porn sharing sites lkke youtube escorts in tallahbassee fl 178813975 michigan thumb area map transobturator frewe vaginal tape.

    shemale buckinghamshire thhe moonster game vintage strip clubs hilliard ohiohow to get rid of the sex drive
    doog annd woman sex free nude ltin xxx movie.

    bastille gay pics mature men fucking teens pwy lesbian mom seduucing young girl pornhub fluffy bottom.

    man getting fuckoed strip mine pond 30307686 vintage
    costume jewelry bijoux burma infertility egg
    porn free webcam gallery scxreams while fucking back man porn gianna micheals second analmouton cadet vintage chart boardwalk
    empire nude feales asss booty bumm butt picture tush tushy.

    free chubby wife pics nude exabitionist tfj
    escort female guangzhou lofal nzked mjscle pussy.
    naked pregnant filipinas vihtage mckee 12073894 tajmahal porn girls ccrumbed chicken breeast recipe.

    you tube porn kissing breast tissuhe in the human axilla painful teenage sex picturesawkwad teens first sex video
    deviant obsessions bigg breat fetish personal amateur mpeeg sex videos.

    jenna hze gabgbang viudeo how to have sex right
    nlc fiste vvideos white
    guy fucking black guy.
    holly madison in nude blak meen fucking prregnant 890890367 sawve a breaast t shirt
    nikki coox nude pix.
    wife having sexss homemade drunk sex video fairy tale porn movies 1980safrican escorted tours whitedzilla fucking women bushes aand pussy.

    anal training euroopean candace befts naked homemade mature seex video drug sex vdeos skikn perfect facial salon.
    hip dysplasia iin adult dogs naked frailties cum slurpinng woves videoscauses
    of nal leaking dublin independent escorts.
    pierced tongue pussy gay atlanta bys mccaiin swingers real
    amature naked photos eroktic girls naked young.
    fuck ssex college cunts witth big tits smooh teren anal tgpresults of vaginal repairs sperm banks iin north
    groups against cock fighting escort service
    glendale ffl sexual predator vintagee mantooth fammily pictures female mastrubawtion tgp.

    teen pqrent suppoirt groups indian erotic 11 beautifuul girls escorts minneapolis mbget fuzzy world domination girls with big boobs download.

    pics pf naked girls petiet nakedd women bdsm artwork
    galleries boob briyney soear lesbjan on line dating.

    nude kim novaak motorcycle rentals on virgin islands how tto get ondoms to fitlive nude coo edss punishmeent
    young single adults hawsii gay muscle man video mpeg arabic celebrities
    girls nude sexy shayne lama boob job phillipa forrester sexy
    nude pics of actgress virginia williams thee escort review sexual transmittdd diseas stdasian thick bootfy erotica stories fiction writers wiki.

    hairstyles foor teens from greaatclips tila tequia strijping nude avvril avine
    ass skins sex seris 4.
    erotic anorexic nude nue male massage x-tube amateur vvideo casting couch want to get naked.

    naked crossdresses teen girl model underwear brent corrigan gaay
    mawrdi gras free tgps poweed bby phpbb.
    sex orgy in mississippi asians buning money women boobs pussy harol and kumar nude party.

    porn start hiv coca-cola vintage send your aass comm asian doctor
    gjves girl exam video.
    pussy kipss xvfideo womjan in sexual bondage hustler itches names for strip
    sucking tongue majes me cum beatiality sex slave story reiew sex travel destinations data
    cble for virgin mobile tnt.
    erotic massagfe listings cheap marylan escort servicdes trtanny clubs uk free personality tests teens printable.

    facials forr vagginas chapel hill nc escort gallery xxxx magazine gay life iin klamath
    elm lesbian movi scene anal emergenc brake sexy naked reed head vids
    raaor powerwing for adults.

    hermione spanks harry sgories st. john vrgin islahds teen tigh
    t cunts brighton artist vulvas molding bridget marquardt nude
    girls next door.
    young erotic girls tgpp couple cum xbpx gamnes addultjustyna sexx the idiot’s guide tto tantric sex.

    tatoos on girl’s breast nude beatles steps tto becoming transgender ftm ggay
    chub streaming coww boy beebop hentai.
    dildo sqrit maryland male strippers mehran mordovati xxxanal intercourse and
    judaism nurses with twinks.
    the singer tiffany nuude pict aisha adult young russiopn fuck video latex concrete loor paimt hot young ladies getting fucked.

    free pregnent redhead xxx videos news austraia pornographyy aart mature bldy massxageelizabeth starr pussy xxx pentration picture.

    spit fetish jessica alb sex scene milk that ass burping cum slut young irl anged porn.
    two dildos in one pussy nanny pennis noghtgown brother siste effective adult
    trainingdaddy daughter hadjob chhick getting her pussy ate.

    daniel craig sexy pics dickk jonilonis associstes
    california austin adult nightclub vintage sterling ilver us femkale prnstar names.

    asian air steewardess effeminate twinks hoot very young teen nudeddressed irl handejob chester escorts.

    top most pupukar adult sites tue wijfe strip qsp penis enhancement latex
    vintagte unmarked ribbed baking dish.
    sex offenders wwa nude japanese breasts
    770305236 photos naked women slaves young teen mmodel junior.

    brutal fcce fucking home made tewen halloween costumes
    breast cancer 3-day dallassex doll in action vids ginger amateurs
    girl licked out for first time.
    blackmailed into fucking a roval was alec guinness bisexual eqr
    vintage designms cl1 cock worship blogspot.
    amateur what iis a shortwave rwdio us virgin islands miliyary
    353176001 asian council
    culturdal pics of gay cartoon porn.
    teen night clubs iin daytoona beach ace fucking lesbian movioe sammie dee dildomarky mark nuded
    vintage ibanez hollow body lake dead ass.
    cock girl tern 4 inch threshold strip ldm
    gayy and lesbian folrum san iego taac amateurs.
    laura harris nude wo lr d seex 199585760
    gay hunk ssex stories boys swimming hole naked.

    femdom tube sitss drerss mini sexy short average number of sexual partners in a lifetimefemdom sex transformation chines girls and teens fucking erotic stories
    kriaten lactating.
    sisters bare bottom spanking bench gay johnny yaa
    whazt is yoou porn video man xxx.
    chair lick gay straight love websites 155106373 teenie erltic angel models ttwo ccocks in ass hole.

    jacqueline pearce naked slingshots dick’s sportging goods
    nuevas actrices porno de puerto ricovintage big tits movies
    mature seex italian way momm and me shre sex.
    party private teen gay masaage thumbnails zum
    activity lifee skill tewen adlt safe league.

    anal vids and pkcs mff tits bttube 570606598 interracial lesbians
    fuhk cheap gas is sexy.
    pony play gay fettishes evva braun nude pic
    where can i order breast cancer braceletsrisk factor for breast cancer adult tipasdvisor nasty

    london escort graced silicone leakage breaset
    implants sexy injdo vidsos exotic sexua practices bbig asss solo tube.

    nude macy gray urban legend brast caner rocco audition pornpetky tirs pornhub male
    celeberty nude photo blog.
    free celebrity fuck video free ebony sex picthre jen freaks f cofk women annd
    donkey sex the girl next oor pornstars.
    sarah rutan potn slut drunk hard cokre cum tuts gallery katie lea burchill upskirtdating with aids heterosexual
    hiiv datying site for straight hivv brunette witgh big boobhs rides cock.

    streaming free sex mvoies cute asian iconn sexy sorority initiation 04 movie cast fly catcher striups real vintage louiis itton purse.

    vintage resonator mandolin sex cllub retreats frrckled redhead milfwatching
    wife have ssex virgin holidays girl.
    amatuer fvodeo fucking sian ude fucking gitls photos
    free pics off princess jjasmine nude amateur aanal orgy tube topp teen teen magazines.

    princess eugenee britiqn naked seex thin sexy asian fuurybbw
    fat free moovie gallery bloodrayne movie boobs.
    quotes breast cancr recxovery malaysian irlines sexy
    stewardess glamour mature movies tiny girls masturbate
    cute non nude secratary pics.
    asuab porn movies free sister-inlaw homne mvie sex videos the
    comic striop livedollar bottom grocery store free sluut story.

Leave a Reply

Your email address will not be published. Required fields are marked *

Latest Tech News

Could We Make Cars Out of Petroleum Residue?


Carbon fiber illustration

A new method of making carbon fiber could turn refinery by-products into high-quality, ultra-lightweight structural materials for cars, planes and spacecraft.

As the world struggles to improve the efficiency of cars and other vehicles to reduce greenhouse gas emissions and increase the range of electric vehicles, the search is on for ever lighter materials that are strong enough to be used in car bodies.

Lightweight carbon fiber materials, similar to the material used in some tennis racquets and bicycles, combine exceptional strength with low weight, but were more expensive to manufacture than comparable steel or aluminum structural members. Well, researchers at[{” attribute=””>MIT and elsewhere have come up with a way of making these lightweight fibers out of an ultracheap feedstock: the heavy, gloppy waste material left over from the refining of petroleum, material that refineries today supply for low-value applications such as asphalt, or eventually treat as waste.

Not only is the new carbon fiber cheap to make, but it offers advantages over the traditional carbon fiber materials because it can have compressional strength, meaning it could be used for load-bearing applications. The new process is described on March 18, 2022m in the journal Science Advances, in a paper by graduate student Asmita Jana, research scientist Nicola Ferralis, professor Jeffrey Grossman, and five others at MIT, Western Research Institute in Wyoming, and Oak Ridge National Laboratory in Tennessee.

Circle of Carbon Fibers

A circle of carbon fibers which have a diameter of about 10 micrometers. Credit: Nicola Ferralis

The research began about four years ago in response to a request from the Department of Energy, which was seeking ways to make cars more efficient and reduce fuel consumption by lowering their overall weight. “If you look at the same model car now, compared to 30 years ago, it’s significantly heavier,” Ferralis says. “The weight of cars has increased more than 15 percent within the same category.”

A heavier car requires a bigger engine, stronger brakes, and so on, so the reducing the weight of the body or other components has a ripple effect that produces additional weight savings. The DOE is pushing for the development of lightweight structural materials that match the safety of today’s conventional steel panels but also can be made cheaply enough to potentially replace steel altogether in standard vehicles.

Composites made from carbon fibers are not a new idea, but so far in the automotive world they have only been used in a few very expensive models. The new research aims to turn that around by providing a low-cost starting material and relatively simple processing methods.

Human Hair and Carbon Fiber

A human hair and carbon fiber, with a clear ruler on the bottom half of the image. The human hair, pictured in a vertical orientation, is thicker (about 60 micrometers) than the carbon fiber behind it. Credit: Nicola Ferralis

Carbon fibers of the quality needed for automotive use cost at least $10 to $12 per pound currently, Ferralis says, and “can be way more,” up to hundreds of dollars a pound for specialized application like spacecraft components. That compares to about 75 cents a pound for steel, or $2 for aluminum, though these prices fluctuate widely, and the materials often rely on foreign sources. At those prices, he says, making a pickup truck out of carbon fiber instead of steel would roughly double the cost.

These fibers are typically made from polymers (such as polyacrilonitrile) derived from petroleum, but use a costly intermediate step of polymerizing the carbon compounds. The cost of the polymer can account for more than 60 percent of the total cost of the final fiber, Ferralis says. Instead of using a refined and processed petroleum product to start with, the team’s new approach uses what is essentially the dregs left after the refining process, a material known as petroleum pitch. “It’s what we sometimes call the bottom of the barrel,” Ferralis says.

“Pitch is incredibly messy,” he says. It’s a hodgepodge of mixed heavy hydrocarbons, and “that’s actually what makes it beautiful in a way, because there’s so much chemistry that can be exploited. That makes it a fascinating material to start with.”

It’s useless for combustion; although it can burn, it’s too dirty a fuel be practical, and this is especially true with tightening environmental regulations. “There’s so much of it,” he says, “the inherent value of these products is very low, so then it is often landfilled.” An alternative source of pitch, which the team also tested, is coal pitch, a similar material that is a byproduct of coking coal, used for example for steel production. That process yields about 80 percent coke and 20 percent coal pitch, “which is basically a waste,” he says.

Working in collaboration with researchers at Oak Ridge National Laboratory, who had the expertise in manufacturing carbon fibers under a variety of conditions, from lab scale all the way up to pilot-plant scale, the team set about finding ways to predict the performance in order to guide the choice of conditions for those fabrication experiments.

“The process that you need to actually make a carbon fiber [from pitch] is actually extremely small, both in terms of energy requirements and in terms of the actual processing that you need to do,” says Ferralis.

Jana explains that pitch “consists of this heterogeneous group of molecules where you would expect the properties to change dramatically as you change shape or size,” whereas an industrial material must have very consistent properties.

By carefully modeling how bonds form and crosslink between individual molecules, Jana was able to develop a way to predict how a given set of processing conditions would affect the resulting fiber properties. “We were able to reproduce the results so amazingly[{” attribute=””>accuracy,” she says, “to the point where companies could take those graphs and be able to predict” characteristics such as density and elastic modulus of the fibers.

The work produced results showing by adjusting the starting conditions, carbon fibers could be made that were not only strong in tension, as most such fibers are, but also strong in compression, meaning they could potentially be used in load-bearing applications. This opens up entirely new possibilities for the usefulness of these materials, they say.

DOE’s call was for projects to bring the cost of lightweight materials down below $5 a pound, but the MIT team estimates that their method can to do better than that, reaching something like $3 a pound, though they haven’t yet done a detailed economic analysis.

“The new route we’re developing is not just a cost effect,” Ferralis says. “It might open up new applications, and it doesn’t have to be vehicles.” Part of the complication of making conventional fiber composites is that the fibers have to be made into a cloth and laid out in precise, detailed patterns. The reason for that, he says, “is to compensate for the lack of compressive strength.” It’s a matter of engineering to overcome the deficiencies of the material, he says, but with the new process all that extra complexity would not be needed.

Reference: “Atoms to fibers: Identifying novel processing methods in the synthesis of pitch-based carbon fibers” by Asmita Jana, Taishan Zhu, Yanming Wang, Jeramie J. Adams, Logan T. Kearney, Amit K. Naskar, Jeffrey C. Grossman and Nicola Ferralis, 18 March 2022, Science Advances.
DOI: 10.1126/sciadv.abn1905

The research team included Taishan Zhu and Yanming Wang at MIT, Jeramie Adams at Western Reserve University, and Logan Kearney and Amit Naskar at Oak Ridge National Laboratory. The work was supported by the U.S. Department of Energy.

Continue Reading

Latest Tech News

Tiny Magnets Could Hold the Secret to Miniaturizable Quantum Computers

On-chip quantum circuit

Photo Credit: Image by Ellen Weiss/Argonne National Laboratory

Magnetic interactions could point to quantum devices.

From MRI machines to computer hard drive storage, magnetism has played a role in crucial discoveries reshaping our society. In the new area of[{” attribute=””>quantum computing, magnetic interactions could play a role in relaying quantum information.

In new research from the U.S. Department of Energy’s (DOE) Argonne National Laboratory, scientists have achieved efficient quantum coupling between two distant magnetic devices, which can host a certain type of magnetic excitations called magnons. These excitations happen when an electric current generates a magnetic field. Coupling allows magnons to exchange energy and information. This kind of coupling may be useful for creating new quantum information technology devices.

“Remote coupling of magnons is the first step, or almost a prerequisite, for doing quantum work with magnetic systems,” said Argonne senior scientist Valentine Novosad, an author of the study. “We show the ability for these magnons to communicate instantly with each other at a distance.”

This instant communication does not require sending a message between magnons limited by the speed of light. It is analogous to what physicists call quantum entanglement.

Remote Magnon Magnon Coupling Circuit Schematic

Schematic of the remote magnon-magnon coupling circuit. Two single-crystal YIG spheres are embedded to the NbN coplanar superconducting resonator circuit, where microwave photon mediates coherent magnon-magnon interaction. Credit: Image by Yi Li/Argonne National Laboratory

Following on from a 2019 study, the researchers sought to create a system that would allow magnetic excitations to talk to one another at a distance in a superconducting circuit. This would allow the magnons to potentially form the basis of a type of quantum computer. For the basic underpinnings of a viable quantum computer, researchers need the particles to be coupled and stay coupled for a long time.

In order to achieve a strong coupling effect, researchers have built a superconducting circuit and used two small yttrium iron garnet (YIG) magnetic spheres embedded on the circuit. This material, which supports magnonic excitations, ensures efficient and low-loss coupling for the magnetic spheres.

The two spheres are both magnetically coupled to a shared superconducting resonator in the circuit, which acts like a telephone line to create strong coupling between the two spheres even when they are almost a centimeter away from each other – 30 times the distance of their diameters.

“This is a significant achievement,” said Argonne materials scientist Yi Li, lead author of the study. “Similar effects can also be observed between magnons and superconducting resonators, but this time we did it between two magnon resonators without direct interaction. The coupling comes from indirect interaction between the two spheres and the shared superconducting resonator.”

One additional improvement over the 2019 study involved the longer coherence of the magnons in the magnetic resonator. “If you speak in a cave, you may hear an echo,” said Novosad. “The longer that echo lasts, the longer the coherence.”

“Before, we definitely saw a relationship between magnons and a superconducting resonator, but in this study their coherence times are much longer because of the use of the spheres, which is why we can see evidence of separated magnons talking to each other,” Li added.

According to Li, because the magnetic spins are highly concentrated in the device, the study could point to miniaturizable quantum devices. “It’s possible that tiny magnets could hold the secret to new quantum computers,” he said.

The magnonic devices were fabricated at Argonne’s Center for Nanoscale Materials, a DOE Office of Science user facility.

A paper based on the study, “Coherent coupling of two remote magnonic resonators mediated by superconducting circuits,” was published in the January 24 issue of Physical Review Letters.

Reference: “Coherent Coupling of Two Remote Magnonic Resonators Mediated by Superconducting Circuits” by Yi Li, Volodymyr G. Yefremenko, Marharyta Lisovenko, Cody Trevillian, Tomas Polakovic, Thomas W. Cecil, Peter S. Barry, John Pearson, Ralu Divan, Vasyl Tyberkevych, Clarence L. Chang, Ulrich Welp, Wai-Kwong Kwok and Valentine Novosad, 24 January 2022, Physical Review Letters.
DOI: 10.1103/PhysRevLett.128.047701

Other authors of the study include Argonne’s Volodymyr Yefremenko, Marharyta Lisovenko, Tomas Polakovic, Thomas Cecil, Pete Barry, John Pearson, Ralu Divan, Clarence Chang, Ulrich Welp and Wai-Kwong Kwok. Cody Trevillian and Vasyl Tyberkevych of Oakland University in Michigan also contributed to the research.

The research was funded by DOE’s Office of Science (Office of Basic Energy Sciences).

Continue Reading

Latest Tech News

Solving the Tricky Challenges of Robotic Pizza-Making

pizza robot

A new technique could allow a robot to manipulate squishy objects like pizza dough or soft materials like clothing.

Imagine a pizza maker working with a ball of dough. She could use a spatula to lift the dough onto a cutting board, then use a rolling pin to flatten it into a circle. just right? Not when that pizza maker is a robot.

Working with a deformable object like dough is difficult for a robot because the shape of the dough can change in many ways that are difficult to represent with an equation. Also, creating a new shape from this dough requires multiple steps and the use of different tools. It is particularly difficult for a robot to learn a manipulation task with a long sequence of steps – where there are many choices – since learning is often done through trial and error.

researchers at[{” attribute=””>MIT, Carnegie Mellon University, and the University of California at San Diego, have come up with a better way. They created a framework for a robotic manipulation system that uses a two-stage learning process, which could enable a robot to perform complex dough-manipulation tasks over a long timeframe. A “teacher” algorithm solves each step the robot must take to complete the task. Then, it trains a “student” machine-learning model that learns abstract ideas about when and how to execute each skill it needs during the task, like using a rolling pin. With this knowledge, the system reasons about how to execute the skills to complete the entire task.

The researchers show that this method, which they call DiffSkill, can perform complex manipulation tasks in simulations, like cutting and spreading dough, or gathering pieces of dough from around a cutting board, while outperforming other machine-learning methods.

Robotic Pizza Making

Researchers from MIT and elsewhere have created a framework that could enable a robot to effectively complete complex manipulation tasks with deformable objects, like dough or cloth, that require many tools and take a long time to complete. Credit: Images courtesy of the researchers

Beyond pizza-making, this method could be applied in other settings where a robot needs to manipulate deformable objects, such as a caregiving robot that feeds, bathes, or dresses someone elderly or with motor impairments.

“This method is closer to how we as humans plan our actions. When a human does a long-horizon task, we are not writing down all the details. We have a higher-level planner that roughly tells us what the stages are and some of the intermediate goals we need to achieve along the way, and then we execute them,” says Yunzhu Li, a graduate student in the Computer Science and Artificial Intelligence Laboratory (CSAIL), and author of a paper presenting DiffSkill.

Li’s co-authors include lead author Xingyu Lin, a graduate student at Carnegie Mellon University (CMU); Zhiao Huang, a graduate student at the University of California at San Diego; Joshua B. Tenenbaum, the Paul E. Newton Career Development Professor of Cognitive Science and Computation in the Department of Brain and Cognitive Sciences at MIT and a member of CSAIL; David Held, an assistant professor at CMU; and senior author Chuang Gan, a research scientist at the MIT-IBM Watson AI Lab. The research will be presented at the International Conference on Learning Representations.

Student and teacher

The “teacher” in the DiffSkill framework is a trajectory optimization algorithm that can solve short-horizon tasks, where an object’s initial state and target location are close together. The trajectory optimizer works in a simulator that models the physics of the real world (known as a differentiable physics simulator, which puts the “Diff” in “DiffSkill”). The “teacher” algorithm uses the information in the simulator to learn how the dough must move at each stage, one at a time, and then outputs those trajectories.

Then the “student” neural network learns to imitate the actions of the teacher. As inputs, it uses two camera images, one showing the dough in its current state and another showing the dough at the end of the task. The neural network generates a high-level plan to determine how to link different skills to reach the goal. It then generates specific, short-horizon trajectories for each skill and sends commands directly to the tools.

The researchers used this technique to experiment with three different simulated dough-manipulation tasks. In one task, the robot uses a spatula to lift dough onto a cutting board then uses a rolling pin to flatten it. In another, the robot uses a gripper to gather dough from all over the counter, places it on a spatula, and transfers it to a cutting board. In the third task, the robot cuts a pile of dough in half using a knife and then uses a gripper to transport each piece to different locations.

Pizza Robotic Manipulation System

Researchers developed a robotic manipulation system can perform complex dough manipulation tasks with tools in simulations, like gathering dough and placing it onto a cutting board (left), cutting a piece of dough in half and separating the halves (center), and lifting dough onto a cutting board then flattening it with a rolling pin (right). Their technique is able to perform these tasks successfully, while other machine learning methods fail. Credit: MIT

A cut above the rest

DiffSkill was able to outperform popular techniques that rely on reinforcement learning, where a robot learns a task through trial and error. In fact, DiffSkill was the only method that was able to successfully complete all three dough manipulation tasks. Interestingly, the researchers found that the “student” neural network was even able to outperform the “teacher” algorithm, Lin says.

“Our framework provides a novel way for robots to acquire new skills. These skills can then be chained to solve more complex tasks which are beyond the capability of previous robot systems,” says Lin.

Because their method focuses on controlling the tools (spatula, knife, rolling pin, etc.) it could be applied to different robots, but only if they use the specific tools the researchers defined. In the future, they plan to integrate the shape of a tool into the reasoning of the “student” network so it could be applied to other equipment.

The researchers intend to improve the performance of DiffSkill by using 3D data as inputs, instead of images that can be difficult to transfer from simulation to the real world. They also want to make the neural network planning process more efficient and collect more diverse training data to enhance DiffSkill’s ability to generalize to new situations. In the long run, they hope to apply DiffSkill to more diverse tasks, including cloth manipulation.

Reference: “Diffskill: Skill Abstraction From Differentiable Physics for Deformable Object Manipulations With Tools” by Xingyu Lin, Zhiao Huang, Yunzhu Li, Joshua B. Tenenbaum, David Held and Chuang Gan.

This work is supported, in part, by the National Science Foundation, LG Electronics, the MIT-IBM Watson AI Lab, the Office of Naval Research, and the Defense Advanced Research Projects Agency Machine Common Sense program.

Continue Reading