Lu'ulu'u na kankara

da lu'ulu'u kankara Koyaushe sun kasance abin nazari da masana kimiyya suka yi la'akari da su na musamman da ban mamaki. Idan muka kalle su a karkashin na'ura mai kwakwalwa za mu iya ganin cewa suna da siffofi na geometric na ban mamaki kuma yana da ban mamaki dalilin da yasa aka samar da waɗannan siffofi a cikin yanayi.

A cikin wannan labarin za mu gaya muku menene ƙarshen bincike daban-daban da suka shafi lu'ulu'u na kankara da abin da aka gano har yau.

samuwar kankara lu'ulu'u

Siffar siffa mai ma'ana sosai saboda girman tafki, inda ake ajiye ruwa kai tsaye akan lu'ulu'u na kankara kuma yana ƙafe. Dangane da yanayin zafi da zafi. Lu'ulu'u na kankara na iya haɓaka daga farkon prisms hexagonal ta hanyoyi masu ma'ana da yawa. Siffofin da za a iya yi na lu'ulu'u na kankara sune columnar, nau'in allura, farantin karfe, da dendritic. Idan crystal yayi ƙaura zuwa yanki na yanayi daban-daban na muhalli, yanayin girma na iya canzawa kuma kristal na ƙarshe na iya nuna yanayin gauraye.

Lu'ulu'u na kankara suna yin faɗuwa tare da dogayen gaturansu masu layi ɗaya a kwance, don haka ana iya gani akan radar yanayi na polarimetric tare da ingantattun dabi'u (tabbatacce). Load ɗin kristal kankara na iya haifar da alignments banda kwance. Radar yanayin yanayi kuma yana iya gano lu'ulu'u masu caji da kyau. Zazzabi da zafi suna ƙayyade nau'ikan crystal iri-iri. Lu'ulu'u na kankara suna da alhakin bayyanar yanayin gani da yawa.

Gizagizai masu daskarewa ana yin su ne da lu'ulu'u na kankara, musamman gajimaren cirrus da hazo mai daskarewa. Lu'ulu'u na kankara a cikin troposphere yana haifar da shuɗin sararin sama ya zama fari kaɗan, wanda zai iya zama alamar gabatowa (da ruwan sama) yayin da iska mai laushi ta tashi kuma ta daskare cikin lu'ulu'u na kankara.

A yanayin zafi na al'ada da matsa lamba, Kwayoyin ruwa suna da nau'in V-dimbin yawa kuma atom ɗin hydrogen guda biyu an haɗa su da atom ɗin oxygen a kusurwar 105°. Lu'ulu'u na kankara gama gari suna da simmetrical da hexagonal

Lokacin da aka matsa tsakanin yadudduka biyu na graphene, lu'ulu'u masu murabba'in kankara suna samuwa a zafin daki. Kayan shine sabon lokacin kristal kankara wanda ya haɗu tare da wasu ƙanƙara 17. Binciken ya biyo bayan binciken da aka yi a baya cewa tururin ruwa da ruwa na iya wucewa ta cikin zanen laminated graphene oxide, sabanin kananan kwayoyin halitta kamar helium. Ana tsammanin sojojin van der Waals ne ke jagorantar wannan tasirin, wanda zai iya haɗa da matsi sama da 10.000.

karatu a kan kankara lu'ulu'u

Kwaikwayon da masu bincike daga CSIC da Jami'ar Complutense ta Madrid suka yi a kan na'urar sarrafa kwamfuta ta MareNostrum da ke Barcelona, ​​sun tabbatar da cewa mabuɗin baƙon girma na lu'ulu'u na kankara yana cikin tsarinsu

Fuskokin kankara na iya kasancewa cikin jihohi uku daban-daban, tare da nau'ikan rashin daidaituwa. Watsawa daga wannan zuwa wancan suna haifar da canje-canje kwatsam a ciki girman girma yayin da yanayin zafi ke tashi da bayyana hanyoyi daban-daban (lalata, hexagonal, ko duka biyu) daga kankara ko lu'ulu'u na dusar ƙanƙara a cikin yanayi.

Makullin waɗannan ƙayyadaddun canje-canjen kristal da haɓaka shine tsarin saman su. Wani binciken da masu bincike Luis González MacDowell daga Jami'ar Complutense ta Madrid (UCM), Eva Noya daga Cibiyar Nazarin Jiki ta Rocca Solano (IQFR) ta Babban Kwamishinan Bincike na Kimiyya da Pablo Llombart daga cibiyoyin biyu suka nuna hakan. . An buga labarin a cikin mujallar Kimiyya Ci gaban.

"Dalilin wannan sauyi ya kasance a asirce har zuwa yanzu," in ji González MacDowell, yana tuna cewa wani mai bincike na Japan Ukichiro Nakaya ya gano a cikin 1930s mafi ƙanƙantar lu'ulu'u na kankara, da ake kira lu'u-lu'u lu'u-lu'u, mai siffar siffar siffar hexagonal prism. Wadannan prisms na iya zama lebur, kamar lozenge, ko elongated, kamar fensir ko prism hexagonal, kuma suna iya canzawa daga wannan siffa zuwa wani a takamaiman zafin jiki.

Simulators

Masu binciken sun lura cewa a yanayin zafi mara kyau, saman kankara yana da santsi kuma yana da tsari. Lokacin da kwayoyin tururi suka yi karo da saman. sun kasa samun inda za su shiga da sauri su kafe. wanda ke sa kristal girma ya ragu sosai.

Amma a yanayin zafi mafi girma, saman kankara ya zama mafi rikicewa, tare da matakai masu yawa. Kwayoyin tururi na iya samun sauƙin samun wurinsu akan matakai kuma lu'ulu'u suna girma cikin sauri.

“Mun lura cewa wannan canjin ba a hankali ba ne, amma ya faru ne saboda wani takamaiman sauyi da ake kira canjin yanayi. Amma abin da ya sa ƙanƙarar ta ƙara zama sabon baƙon shine kwatsam, lokacin da harsashi na waje na kristal ya narke, saman ya sake yin santsi kuma ya sake dagulewa," in ji Nuhu.

Lokacin da ya sake zama santsi sosai, haɓakar kristal ya zama sannu a hankali a wancan gefen crystal, amma ba a wancan gefen ba. Nan da nan wasu suna girma da sauri, wasu kuma suna girma a hankali, kuma siffar lu'ulu'u suna canzawa. kamar yadda Nakatani ya gani a gwaje-gwaje sama da shekaru 90 da suka gabata.

Simulation a cikin MareNostrum

Ganin cewa kankara wani abu ne mai rikitarwa wanda ke buƙatar yin nazari ta hanyar amfani da dabarun gwaji saboda saurin fitar da shi, an kwashe watanni takwas ana yin simulators akan kwamfuta mafi girma a Spain, MareNostrum (BSC-CNS).

"Ayyukan lissafin ya ba mu damar sanin hanyar kowane kwayoyin ruwa wanda ke samar da crystal; amma ba shakka, don samar da ƙaramin crystal, muna buƙatar dubban ɗaruruwan kwayoyin halitta, don haka adadin lissafin da ake buƙata don yin wannan binciken yana da yawa. in ji Llombart Say.

González MacDowell ya ƙarasa da cewa waɗannan sakamakon suna da ban sha'awa sosai, amma binciken kimiyya koyaushe yana buƙatar tabbatar da sabbin ƙididdiga da inganci. Duk da wannan taka-tsantsan, mun ji daɗin cewa ƙoƙarinmu ya haifar da sakamako mai ban sha'awa, saboda an ɗauki ƙoƙari da yawa da ba a yi nasara ba don samun kuɗi."

Bugu da ƙari, masanin ilimin sunadarai ya tuna cewa lu'ulu'u na dusar ƙanƙara suna taka muhimmiyar rawa a dumamar yanayi: "Don fahimtar tasirin canjin yanayi, muna buƙatar fahimtar siffarsa da ƙimar girma. Don haka kyakkyawar fahimtarmu ta ba mu damar sanya wani yanki a cikin ƙwaƙƙwaran dala miliyan. "

Ina fatan cewa tare da wannan bayanin zaku iya ƙarin koyo game da lu'ulu'u na kankara da halayensu.