检索结果-南通市图书馆

维普期刊数据库

Challenges i. hydrogen adsorpti.ns： from physi.orpti.n to chemi.orpti.n

在线全文

学校读者我要写书评

暂无评论

Fronti.rs of physi.s 2011年第2期6卷 142-150页

作者： Feng Di.G Bori. i. YAKOBSON i.sti.ute of Texti.e and Clothi.g Hong Kong Polytechnic University Kowloon Hong Kong China Department of Materi.l Sci.nce and Mechani.al Engi.eeri.g Department of Chemistry Rice University Houston TX 77005 USA

i. thi. short revi.w, we wi.l bri.fly di.cuss the story of hydrogen storage, i.s i.pact on clean energy appli.ati.n, especi.lly the challenges of usi.g hydrogen adsorpti.n for onboard appli.ati.n. After a short compari.on of the mai. methods of hydrogen storage （hi.h pressure tank, metal hydri.e and adsorpti.n）, we wi.l focus our di.cussi.n on adsorpti.n of hydrogen i. graphi.i. carbon based large surface area adsorbents i.cludi.g carbon nanotubes, graphene and metal organi. frameworks. The mechani.ms, advantages, di.advantages and recent progresses wi.l be di.cussed and revi.wed for physi.orpti.n, metal-assi.ted storage and chemi.orpti.n. i. the last secti.n, we wi.l di.cuss hydrogen spi.lover chemi.orpti.n i. detai. for the mechani.m, status, challenges and perspecti.es. We hope to present a clear pi.ture of the present technologi.s, challenges and the perspecti.es of hydrogen storage for the future studi.s.

关键词： hydrogen storage physi.orpti.n chemi.orpti.n spi.lover

The relati.nshi. between i.traspeci.i. assortati.e mati.g and reproducti.e i.olati.n between di.ergent populati.ns

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Zoology 2012年第3期58卷 484-492页

作者： Dani.l i. BOLNi.K Mark Ki.KPATRi.K Howard Hughes Medi.al i.sti.ute and Secti.n of i.tegrati.e Bi.logy One University Station C0930 University of Texas at Austin Austin TX 78712 USA Secti.n of i.tegrati.e Bi.logy One University Station C0930 University of Texas at Austin Austin TX 78712 USA

The term ＇assortati.e mati.g＇ has been appli.d to descri.e two very di.ferent phenomena：（1） the tendency for i.di. vi.uals to choose phenotypi.ally si.i.ar mates from among conspeci.i.s; or （2） the tendency to prefer conspeci.i. over hete- rospeci.i. mates （behavi.ral reproducti.e i.olati.n）. Both forms of assortati.e mati.g are wi.espread i. nature, but the relati.n- shi. between these behavi.rs remai.s unclear. Namely, i. i. plausi.le that a preference for phenotypi.ally si.i.ar conspeci.i.s i. ci.entally reduces the probabi.i.y of mati.g wi.h phenotypi.ally di.ergent heterospeci.i.s. We present a model to calculate how the level of reproducti.e i.olati.n depends on i.traspeci.i. assortati.e mati.g and the phenotypi. di.ergence between speci.s. For empi.i.ally reasonable levels of i.traspeci.i. assortment on a si.gle trai. axi., we show that strong reproducti.e i.olati.n requi.es very substanti.l phenotypi. di.ergence. We i.lustrate thi. poi.t by applyi.g our model to empi.i.al data from threespi.e sti.kleback Gasterosteus aculeatus and Darwi.＇s Fi.ches （Geospi.a spp）. We conclude that typi.al levels of i.traspeci.i. assortment cannot generally be extrapolated to explai. levels of i.terspeci.i. reproducti.e i.olati.n. i.stead, reproducti.e i.olati.n between speci.s li.ely ari.es from di.ferent mate choi.e behavi.rs, or multi.ari.te assortati.e mati.g [Current Zoology 58 （3）： 484-492, 2012].

关键词： Assortati.e mati.g Hybri.i.ati.n Mati.g preference Reproducti.e i.olati.n Speci.ti.n

Novel techni.ue for measurement of coati.g layer thi.kness of fi.e and porous parti.les usi.g focused i.n beam

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Parti.uology 2019年第1期17卷 190-198页

作者： M. Gosli.ska i. Selmer C. Kleemann U.Kulozi. i. Smi.nova S. Hei.ri.h Hamburg Uni.ersi.y of Technology Institute of Solids Process Engineering and Particle TechnologyDenickestr1521073 HamburgGermany Hamburg Uni.ersi.y of Technology Institute of Thermal Separation ProcessesEiJ^endorfer Str. 3821073 HamburgGermany Techni.al Uni.ersi.y of Muni.h Chair of Food and Bioprocess EngineeringWeihenstephaner Berg 185354 FreisingGermany

A novel techni.ue for the measurement of the coati.g layer thi.kness of fi.e parti.les was developed i. thi. work based on cross-secti.ni.g of mi.rometre-si.ed si.gle coated parti.les usi.g focused i.n beam (Fi.) mi.li.g. Thi. techni.ue was tested on two batches of aerogel parti.les coated wi.h thi. coati.gs i. a spouted bed. The Fi. mi.li.g procedure consi.ted of two steps. Fi.st, the desi.ed part of the coated parti.le was removed usi.g a hi.h i.n beam current. The resulti.g cross-secti.ned area was then poli.hed usi.g a lower i.n beam current to make the cross-secti.n clearly vi.i.le. The Fi. mi.li.g process was controlled wi.h si.ultaneous scanni.g electron mi.roscopy (SEM). Afterwards, the coati.g layer thi.kness was evaluated usi.g the SEM i.ages. The coati.g layer was successfully appli.d on the porous aerogel mi.roparti.les i. the spouted bed. The coati.g uni.ormi.y of the hi.hly porous parti.les i.creased wi.h i.creasi.g sprayed coati.g soluti.n amount, wi.h up to 91% of the parti.le pores bei.g covered. The Fi.-cross-secti.ni.g techni.ue usi.g an i.n beam of 2.50 nA for the fi.st mi.li.g and 0.43 nA for poli.hi.g of the surface resulted i. successful generati.n of cross-secti.ns of representati.e parti.les wi.h a vi.i.le parti.le core and coati.g layer. A coati.g layer thi.kness of approxi.ately 700 nm was achi.ved on parti.les wi.h si.es of below 45 μm.

关键词： Coati.g layer thi.kness Focused i.n beam Mi.roparti.le Aerogel Spouted bed Di.ute spouti.g

Growth of large-area ali.ned pentagonal graphene domai.s on hi.h-i.dex copper surfaces

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2016年第7期9卷 2182-2189页

作者： Kai.un Xi. Vasi.i. i. Artyukhov Li.ei.Sun Ji.gyi.g Zheng Li.i.g Ji.o Bori. i. Yakobson Yi.gyi.g Zhang Department of Chemi.try Tsinghua University Beijing 100084 China Center for Nano and Mi.ro Mechani.s Tsinghua University Beijing 100084 China Department of Materi.ls Sci.nce and Nano Engi.eeri.g Rice University Houston TX 77005 USA

Si.gle-crystal graphene domai.s grown by chemi.al vapor deposi.i.n （CVD） i.tri.si.ally tend to have a si.-fold symmetry; however, several factors can i.fluence the growth ki.eti.s, whi.h can i. turn lead to the formati.n of graphene wi.h di.ferent shapes. Here we report the growth of ori.nted large-area pentagonal si.gle-crystal graphene domai.s on Cu foi.s by CVD. We found that hi.h-i.dex Cu planes contri.uted selecti.ely to the formati.n of pentagonal graphene. Our results i.di.ated that latti.e steps present on the crystalli.e surface of the underlyi.g Cu promoted graphene growth i. the di.ecti.n perpendi.ular to the steps and fi.ally led to the di.appearance of one of the edges formi.g a pentagon. i. addi.i.n, hydrogen promoted the formati.n of pentagonal domai.s. Thi. work provi.es new i.si.hts i.to the mechani.m of graphene growth.

关键词： pentagonal graphene copper foi. hi.h i.dex plane chemi.al vapor deposi.i.n large area

Ground State Energy Calculati.ns of i.oelectroni. Seri.s of He i. Double-Zeta Approxi.ati.n Usi.g Coulomb Potenti.l wi.h Noni.teger i.di.es

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chi.ese Physi.s Letters 2008年第3期25卷 896-898页

作者： GUSEi.OV i. i.rafi. AKSU Hüseyi. Department of Physi.s Faculty of Arts and Sciences Onsekiz Mart University Canakkale Turkey

Usi.g formulae for one- and two-electron i.tegrals of Coulomb i.teracti.n potenti.l fk （r） = r^-k wi.h non-i.teger i.di.es k establi.hed by one of the authors wi.h the help of complete orthonormal sets of ψ^α-exponenti.l-type orbi.als （α = 1, 0,-1,-2,…）, we perform the calculati.ns for i.oelectroni. seri.s of the He atom contai.i.g nuclear charges from 2 to 10, where k = 1 - μ （-1 〈 μ 〈 0）. For thi. purpose we have used the double-zeta approxi.ati.n, the confi.urati.n i.teracti.n and coupled-cluster methods employi.g the i.teger-n Slater-type orbi.als as basi. sets. i. i. demonstrated that the results of calculati.ns obtai.ed are better than the numeri.al Hartree-Fock values.

关键词： SLATER-TYPE ORBi.ALS MULTi.ENTER i.TEGRALS ONE-ELECTRON OPEN-SHELLS SYSTEMS i.TEGER ATOMS

Response of plasma turbulence agai.st externally-controlled perturbati.ns

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chi.ese Physi.s B 2012年第9期21卷 385-395页

作者： S. i. i.oh K. i.oh Research i.sti.ute for Appli.d Mechani.s Kyushu University i.oh Research Center for Plasma Turbulence Kyushu University Nati.nal i.sti.ute for Fusi.n Sci.nce

A theory of the dynami. response of the turbulent plasma agai.st the externally-controlled perturbati.ns i. reported. Based on Mori.s method [Prog. Theor. Phys. 33 423 （1965）], the nonli.ear force i. assmned to be separated i.to the memory functi.n and the nonli.ear fluctuati.g force. The former corresponds to the dampi.g term, and the latter i. categori.ed i.to the noi.e term. The response of the turbulent plasma agai.st the externally-controlled source i. formulated. The response kernel, whi.h connects the externally-controlled source and the response of the turbulent fi.ld, i. shown to have both the nonlocal property （i. space） and the non-Markovi.n response （i. ti.e）. A di.cussi.n i. made on the nonlocal and non-Markovi.n response, i.cludi.g the case of di.parate-scale i.teracti.ns. A new method i. proposed to observe experi.entally the nonlocal i.teracti.n i. the dri.t wave turbulence vi. the zonal flows.

关键词： turbulent transport nonlocal and non-Markovi.n response

维普期刊数据库

Hybri. flexural components： Testi.g pre-stressed steel and Gi.RP bars together as rei.forcement for flexural members

在线全文

学校读者我要写书评

暂无评论

Fronti.rs of Structural and Ci.i. Engi.eeri.g 2018年第3期12卷 352-360页

作者： Mohammed FARUQi.Oved i. MATA Franci.co AGUi.i.A Department of Ci.i. and Archi.ectural Engi.eeri.g Texas A&M University Kingsville TX 77843 USA

Concrete members hi.tori.ally have used ei.her pre-stressed steel or steel bars. i. recent years there has been an i.creased i.terest i. the use of fi.er rei.forced polymer （FRP） materi.ls. However, the flexure behavi.r of a hybri. system rei.forced by the combi.ati.n of pre-stressed steel and glass fi.er rei.forced （GFRP） i. sti.l relati.ely unknown. The purpose of thi. work i. to study thi.. Two slabs of 100 and 150-mi.li.eter thi.kness, wi.h a span of 2.1 m rei.forced wi.h both pre-stressi.g steel and GFRP were constructed and tested to fai.ure usi.g ACi.318-11 and ACi.440.1 R-15. The concrete had strength of 31 MPa and the slabs were respecti.ely rei.forced wi.h 5#4 bars and 3#5 bars. Each slab had 37.41 mm2 prestressi.g wi.e wi.h a fai.ure stress of 1722.5 MPa. The experi.ental flexural strength and deflecti.n of slabs were compared wi.h thei. respecti.e si.es theoreti.al slabs. The theoreti.al slabs were ei.her rei.forced wi.h pre-stressed steel or GFRP rebars, or a hybri. system. i. was found that the hybri. system produces better results.

关键词： Parti.l pre-stressi.g composi.e structures GFRP bars

Development of damage probabi.i.y matri.es based on Greek earthquake damage data

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Earthquake Engi.eeri.g and Engi.eeri.g Vi.rati.n 2011年第1期10卷 129-141页

作者： Anastasi. K. Eleftheri.dou Athanasi.s i. Karabi.i. Laboratory of Rei.forced Concrete Department of Civil EngineeringDemocritus University of ThraceGreece

A comprehensi.e study i. presented for empi.i.al sei.mi. vulnerabi.i.y assessment of typi.al structural types, representati.e of the bui.di.g stock of Southern Europe, based on a large set of damage stati.ti.s. The observati.nal database was obtai.ed from post-earthquake surveys carri.d out i. the area struck by the September 7, 1999 Athens earthquake. After analysi. of the collected observati.nal data, a uni.i.d damage database has been created whi.h compri.es 180,945 damaged bui.di.gs from/after the near-fi.ld area of the earthquake. The damaged bui.di.gs are classi.i.d i. speci.i. structural types, accordi.g to the materi.ls, sei.mi. codes and constructi.n techni.ues i. Southern Europe. The sei.mi. demand i. descri.ed i. terms of both the regi.nal macrosei.mi. i.tensi.y and the rati. αg/ao, where αg i. the maxi.um peak ground accelerati.n （PGA） of the earthquake event and ao i. the uni.ue value PGA that characteri.es each muni.i.ali.y shown on the Greek hazard map. The relati.e and cumulati.e frequenci.s of the di.ferent damage states for each structural type and each i.tensi.y level are computed i. terms of damage rati.. Damage probabi.i.y matri.es （DPMs） and vulnerabi.i.y curves are obtai.ed for speci.i. structural types. A compari.on analysi. i. fulfi.led between the produced and the exi.ti.g vulnerabi.i.y models.

关键词： sei.mi. vulnerabi.i.y observati.nal earthquake damage damage probabi.i.y matri.es (DPMs) vulnerabi.i.y curves post-earthquake surveys Athens earthquake exi.ti.g bui.di.gs

维普期刊数据库

A Desi.n and Comparati.e i.vesti.ati.n of Graded AlxGa1–xN EBL for W-B0.375Ga N/W-B0.45GaN Edge Emi.ti.g Laser Di.de on AlN Substrate

在线全文

学校读者我要写书评

暂无评论

Chi.ese Journal of Electroni.s 2022年第4期31卷 683-689页

作者： Ni.SS Mussaab i. WANG Fang Li. Yuhuai Nati.nal Center for i.ternati.nal Joi.t Research of Electroni. Materi.ls and Systems International Joint-Laboratory of Electronic Materials and Systems of Henan Province School of Information EngineeringZhengzhou University Zhengzhou Way Do Electroni.s Co.Ltd. Research i.sti.ute of i.dustri.l Technology Co.Ltd. Zhengzhou University i.sti.ute of Materi.ls and Systems for Sustai.abi.i.y Nagoya University

i. thi. paper, we numeri.ally demonstrated the possi.i.i.y of usi.g wurtzi.e boron galli.m ni.ri.e(W-BGa N) as acti.e layers(quantum well and quantum barri.rs) along wi.h alumi.um galli.m ni.ri.e(Al Ga N) to achi.ve lasi.g at a deep ultravi.let range at 263nm for edge emi.ti.g laser di.de. The laser di.de structure si.ulati.ns were conducted by usi.g the Crossli.htLASTi. software wi.h a self-consi.tency model for vari.s quanti.y calculati.ns. Moreover, multi.le desi.ned structures such as full and half have been achi.ved as well as the study of the effect of gradi.g engi.eeri.g/techni.ues at the electron blocki.g layer for li.early-graded-down and li.early-graded-up gradi.g techni.ues were also emphasi.ed. As a result, a maxi.um emi.ted power of 26 W,a mi.i.um threshold current of 308 m A, a slope effi.i.ncy of 2.82 W/A, and a mi.i.um p-type resi.ti.i.y of0.228 Ω·cm from the di.ferent dopi.g concentrati.ns and geometri.al di.tances were thoroughly observed and jotted down.

关键词： Edge emi.ti.g laser di.des (EELD) Semi.onducti.g alumi.um compounds Heterojuncti.n semi.onductor devi.es Quantum wells