检索结果-南通市图书馆

Nano-Micro Letters 2010年第3期2卷 154-159页

作者： L.A.Li S.H.Cheng H.D.Li Q.Yu j.w.liu X.Y.Lv State Key Laboratory of Superhard Materials Jilin University

In this paper,we report the effect of nitrogen on the deposition and properties of boron doped diamond films synthesized by hot filament chemical vapor *** diamond films consisting of micro-grains(nano-grains) were realized with low(high) boron source flow rate during the growth *** transition of micro-grains to nano-grains is speculated to be strongly(weekly) related with the boron(nitrogen) flow *** grain size and Raman spectral feature vary insignificantly as a function of the nitrogen introduction at a certain boron flow *** variation of electron field emission characteristics dependent on nitrogen is different between microcrystalline and nanocrystalline boron doped diamond samples,which are related to the combined phase composition,boron doping level and texture *** is an optimum nitrogen proportion to improve the field emission properties of the boron-doped films.

关键词： Chemical vapor deposited diamond film Nitrogen effect Boron doping Microcrystalline Nanocrystalline Electron field emission

Improvement on hydrogen generation properties of Zr(BH4)4·8NH3

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2021年第1期31卷 41-46页

作者： D.F.wu L.Z.Ouyang j.M.Huang j.w.liu H.wang X.S.Yang H.Shao M.Zhu School of Materials Science and Engineering Guangdong Provincial Key Laboratory of Advanced Energy Storage Materials South China University of Technology Guangdong Research Institute of Rare Metals Guangdong Key Laboratory of Rare Earth Development and Application China-Australia joint Laboratory for Energy & Environmental Materials Key Laboratory of Fuel Cell Technology of Guangdong Province Advanced Manufacturing Technology Research Centre Department of Industrial and Systems Engineering The Hong Kong Polytechnic University joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials Engineering (IAPME) University of Macau

Hydrolysis of Zr(BH4)4·8NH3in deionized water can generate high purity hydrogen at room ***, the sluggish hydrolysis kinetics of Zr(BH4)4·8NH3hinders its practical use. To improve its hydrogen generation properties, the effects of magnetic stirring, changing hydrolysis solution and tuning the ammonia coordination number on the hydrolysis properties of Zr(BH4)4·8NH3were investigated. Results show that both changing hydrolysis solution and tuning the ammonia coordination number can enhance the hydrolysis *** hydrolysis kinetics properties of Zr(BH4)4·8NH3were significantly improved in MgCl2and *** Zr(BH4)4·8NH3(x ≤ 8) samples were synthesized by a ball-milling method with different ammonization time(10, 60 and 180 min). Both the hydrolysis kinetics and hydrogen yield of Zr(BH4)4·8NH3(x ≤ 8) were enhanced as the ammonia coordination number(x) decreased. Thus, tuning ammonia coordination number is an effective way to control the hydrolysis properties of Zr(BH4)4·8NH3(x ≤ 8).

关键词： Hydrogen production Zr(BH4)4·8NH3 Hydrolysis properties Ammonia coordination number

A New Distributed Localization Algorithm for ZigBee wireless Networks

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

A New Distributed Localization Algorithm for ZigBee Wireless...

An Introduction to Advanced Hot-Formed Steel for Automobile

2009中国控制与决策会议

作者： j.Chen~11,X.j.wu~1,P.Z.wen~2,F.Ye~1,j.w.liu~1 1.Harbin Institute of Technology Shenzhen Graduate School,Shenzhen 518055,China 2.Guilin University of Electronic Technology,Guilin 541004,China

＜正＞Node localization becomes an exciting research area for recently large emergence of ZigBee based wireless applications,where received signal strength indication is adopted as a coarse but simple method on range measurement. Compared with the centralized approach,distributed algorithm that nodes locally calculate their own position coordinates can significantly reduce location-related network traffic;however,this is an intensive *** commercial digital- hardware-block based method used in CC2431,we propose a novel distributed algorithm that can be implemented based on common 8-bit *** this algorithm,instead of ’log-normal’,’piecewise linear’ path loss model was established, which let only linear operation when estimating range from ***,min-max method,other than maximum likelihood estimation method,was used to simplify coordinate ***,ZigBee compatible sensor node modules were developed to carry out the contrast experiments,and results demonstrate the new method has close or even better precision compared with basic algorithm,but with lower cost.

关键词： ZigBee Node localization RSSI Distributed algorithm

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2014年第3期27卷 373-382页

作者： w.j.liu Research Academy Northeastern University

A recently developed advanced hot-formed （AHF） steel for automobile is introduced and three physical metallurgy concepts based on which the AHF steel was designed are reviewed, they are dynamic carbon partitioning （DCP）, flash copper precipitation and bake toughening. AHF steel is an upgrade of the existing hot-formed steel especially suitable for making components with superior crashworthiness; it can be processed by regular hot stamping equipment and process. A kinetics model for DCP is expressed in detail, which can be used to calculate the volume fraction of retained austenite based on four materials and processing parameters. The flash copper precipitation used as an additional strengthening mechanism for AHF steel is also discussed and its ultrafast kinetics can be attributed to the enhancement of quenched-in vacancies on copper diffusion. Also, the bake toughening of AHF steel is addressed; the mechanism of which may be related to the elimination of the less stable block-like retained austenite.

关键词： Advanced hot-formed (AHF) steel Dynamic carbon partitioning Flash copper precipitation Bake toughening Hot stamping

A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第1期20卷 291-304页

作者： Simeon C.Daeschler Katelyn j.w.So Konstantin Feinberg Marina Manoraj jenny Cheung jennifer Zhang Kaveh Mirmoeini jPaul Santerre Tessa Gordon Gregory HBorschel SickKids Research Institute Neuroscience and Mental Health ProgramTorontoONCanada Institute of Biomaterials and Biomedical Engineering University of TorontoTorontoONCanada Indiana University School of Medicine IndianapolisINUSA Division of Plastic and Reconstructive Surgery the Hospital for Sick ChildrenTorontoONCanada Translational Biology and Engineering Program Ted Rogers Centre for Heart ResearchInstitute of Biomedical EngineeringFaculty of DentistryUniversity of TorontoTorontoONCanada

Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong ***,there are no FDA-approved therapies available to promote nerve *** accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve *** authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug *** is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 *** and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible *** released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic *** its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

关键词： biodegradable local drug delivery nerve injury nerve regeneration nerve wrap tacrolimus

Compressive property and energy absorption characteristic of interconnected porous Mg-Zn-Y alloys with adjusting Y addition

在线全文

学校读者我要写书评

暂无评论

journal of Magnesium and Alloys 2024年第1期12卷 171-185页

作者： j.A.liu S.j.liu B.wang w.B.Sun X.j.liu Z.w.Han College of Materials Science and Engineering Key Laboratory of Automobile Materials(Ministry of Education)Jilin UniversityChangchun 130022PR China Key Laboratory of Bionic Engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022PR China weihai Institute for Bionics-jilin University Weihai 264205PR China

In this study,interconnected porous Mg-2Zn-xY alloys with different phase compositions were prepared by various Y additions(x=0.4,3,and 6 wt.%)to adjust the compressive properties and energy absorption *** characterization methods were then applied to identify the microstructure of the porous Mg-Zn-Y and describe the details of the second *** tests were performed at room temperature(RT),200℃,and 300℃to study the impact of the Y addition and testing temperature on the compressive properties of the porous *** experimental results showed that a high Y content promotes a microstructure refinement and increases the volume fraction of the second *** the Y content increases,different Mg-Zn-Y ternary phases appear:I-phase(Mg_(3)Zn_(6)Y),w-phase(Mg_(3)Zn_(3)Y_(2)),and LPSO phase(Mg_(12)ZnY).when the Y content ranges between 0.4%and 6%,the compressive strength increases from 6.30MPa to 9.23 MPa,and the energy absorption capacity increases from 7.33 Mj/m^(3)to 10.97 Mj/m^(3)at RT,which is mainly attributed to the phase composition and volume fraction of the second ***,the average energy absorption efficiency is independent of the Y *** addition,the compressive deformation behaviors of the porous Mg-Zn-Y are altered by the testing *** compressive strength and energy absorption capacity of the porous Mg-Zn-Y decrease due to the softening effect of the high temperature on the *** deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

关键词： Porous magnesium Rare earth elements Microstructure Compressive behavior Energy absorption characteristic

A review on MBE-grown HgCdSe infrared materials on GaSb(211)B substrates

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2019年第1期28卷 116-125页

作者： Z K Zhang w w Pan j L liu w Lei Department of Electrical Electronic and Computer EngineeringThe University of Western Australia35 Stirling HighwayCrawley 6009Australia

we review our recent efforts on developing HgCdSe infrared materials on Ga Sb substrates via molecular beam epitaxy(MBE) for fabricating next generation infrared detectors with features of lower production cost and larger focal plane array format size. In order to achieve high-quality HgCdSe epilayers, ZnTe buffer layers are grown before growing HgCdSe, and the study of misfit strain in ZnTe buffer layers shows that the thickness of ZnTe buffer layer needs to be below 300 nm in order to minimize the generation of misfit dislocations. The cut-off wavelength/alloy composition of HgCdSe materials can be varied in a wide range by varying the ratio of Se/Cd beam equivalent pressure during the HgCdSe *** temperature presents significant impact on the material quality of HgCdSe, and lower growth temperature leads to higher material quality for HgCdSe. Typically, long-wave infrared HgCdSe(x = 0.18, cut-off wavelength of 10.4 μm at 80 K) presents an electron mobility as high as 1.3×10~5cm^2·V^(-1)·s^(-1), a background electron concentration as low as 1.6×10^(16)cm^(-3), and a minority carrier lifetime as long as 2.2 μs. These values of electron mobility and minority carrier lifetime represent a significant improvement on previous studies of MBE-grown HgCdSe reported in the open literatures,and are comparable to those of counterpart HgCdTe materials grown on lattice-matched CdZnTe substrates. These results indicate that HgCdSe grown at the University of western Australia, especially long-wave infrared can meet the basic material quality requirements for making high performance infrared detectors although further effort is required to control the background electron concentration to below 10^(15)cm^(-3). More importantly, even higher quality HgCdSe materials on GaSb are expected by further optimizing the growth conditions, using higher purity Se source material, and implementing postgrowth thermal annealing and defect/impurity gettering/filtering. Our results demonst

关键词： infrared detector HgCdSe GaSb molecular beam epitaxy

Nonlinear free vibration of piezoelectric cylindrical nanoshells

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2019年第5期40卷 601-620页

作者： Yanqing wANG Yunfei liu j.w.ZU Department of Mechanics Northeastern University Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern University Schaefer School of Engineering and Science Stevens Institute of Technology

The nonlinear vibration characteristics of the piezoelectric circular cylindrical nanoshells resting on an elastic foundation are analyzed. The small scale effect and thermo-electro-mechanical loading are taken into account. Based on the nonlocal elasticity theory and Donnell's nonlinear shell theory, the nonlinear governing equations and the corresponding boundary conditions are derived by employing Hamilton's principle. Then,the Galerkin method is used to transform the governing equations into a set of ordinary differential equations, and subsequently, the multiple-scale method is used to obtain an approximate analytical solution. Finally, an extensive parametric study is conducted to examine the effects of the nonlocal parameter, the external electric potential, the temperature rise, and the winkler-Pasternak foundation parameters on the nonlinear vibration characteristics of circular cylindrical piezoelectric nanoshells.

关键词： piezoelectric cylindrical nanoshell nonlinear vibration Donnell's nonlinear shell theory nonlocal elasticity theory multiple-scale method size effect

Treating amyotrophic lateral sclerosis with allogeneic Schwann cell-derived exosomal vesicles: a case report

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第4期20卷 1207-1216页

作者： Pascal j.Goldschmidt-Clermont Aisha Khan George jimsheleishvili Patricia Graham Adriana Brooks Risset Silvera Alexander j.P.Goldschmidt Damien D.Pearse w.Dalton Dietrich Allan D.Levi james D.Guest Miller School of Medicine University of MiamiMiamiFLUSA Stem Cell Institute Miller School of MedicineUniversity of MiamiMiamiFLUSA The Miami Project to Cure Paralysis Miller School of MedicineUniversity of MiamiMiamiFLUSA Alzady International LLC MiamiFLUSA Neurological Surgery Miller School of MedicineUniversity of MiamiMiamiFLUSA

Schwann cells are essential for the maintenance and function of motor neurons,axonal networks,and the neuromuscular *** amyotrophic lateral sclerosis,where motor neuron function is progressively lost,Schwann cell function may also be ***,important signaling and potential trophic activities of Schwann cell-derived exosomal vesicles have been *** case report describes the treatment of a patient with advanced amyotrophic lateral sclerosis using serial intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles,marking,to our knowledge,the first instance of such *** 81-year-old male patient presented with a 1.5-year history of rapidly progressive amyotrophic lateral *** initial diagnosis,the patient underwent a combination of generic riluzole,sodium phenylbutyrate for the treatment of amyotrophic lateral sclerosis,and *** patient volunteered to participate in an FDA-approved single-patient expanded access treatment and received weekly intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles to potentially restore impaired Schwann cell and motor neuron *** confirmed that cultured Schwann cells obtained from the amyotrophic lateral sclerosis patient via sural nerve biopsy appeared impaired(senescent)and that exposure of the patient’s Schwann cells to allogeneic Schwann cell-derived exosomal vesicles,cultured expanded from a cadaver donor improved their growth capacity in *** a period of observation lasting 10 weeks,during which amyotrophic lateral sclerosis Functional Rating Scale-Revised and pulmonary function were regularly monitored,the patient received weekly consecutive infusions of 1.54×1012(×2),and then consecutive infusions of 7.5×1012(×6)allogeneic Schwann cell-derived exosomal vesicles diluted in 40 mL of Dulbecco’s phosphate-buffered *** of the infusions were associated with adverse events such as infusion reactions(allergic or otherwise)or

关键词： allogeneic amyotrophic lateral sclerosis exosomes infusion neuromuscular junction Schwann cell

Periodic interstellar scintillation variations of PSRs j0613-0200 and j0636+5128 associated with the Local Bubble shell

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2023年第11期66卷 221-232页

作者： Yulan liu Robert A.Main joris P.w.Verbiest Ziwei wu Krishnakumar M.Ambalappat jiguang Lu David j.Champion Ismael Cognard Lucas Guillemot Kuo liu james w.Mc Kee Nataliya Porayko Golam.M.Shaifullah Gilles Theureau National Astronomical Observatories Chinese Academy of SciencesBeijing100101China Fakultät für Physik Universität BielefeldBielefeld33501Germany Max-Planck-Institut für Radioastronomie Bonn53121Germany Florida Space Institute University of Central FloridaOrlandoFL32826USA Station de radioastronomie de Nançay Observatoire de ParisNançay18330France Laboratoire de Physique et Chimie de l’Environnement et de l’Espace Universitéd’OrléansOrléans45071France E.A.Milne Centre for Astrophysics University of HullHullHU67RXUK Centre of Excellence for Data Science Artificial Intelligence and ModellingUniversity of HullHullHU67RXUK Dipartimento di Fisica“G.Occhialini” Universitàdi Milano-BicoccaMilano20126Italy INAF-Osservatorio Astronomico di Cagliari Selargius(CA)09047Italy INFN Sezione di Milano-BicoccaMilano20126Italy

Annual variations of interstellar scintillation can be modelled to constrain parameters of the ionized interstellar *** a pulsar is in a binary system,then investigating the orbital parameters is possible through analysis of the orbital variation of *** observations carried out from 2011 to 2020 by the European Pulsar Timing Array radio telescopes,PSRs j0613-0200and j0636+5128 show strong annual variations in their scintillation velocity,while the former additionally exhibits an orbital *** theory and Markov-chain-Monte-Carlo methods are used to interpret these periodic *** assume a thin and anisotropic scattering screen model,and discuss the mildly and extremely anisotropic scattering *** j0613-0200is best described by mildly anisotropic scattering,while PSR j0636+5128 exhibits extremely anisotropic *** measure the distance,velocity,and degree of anisotropy of the scattering screen for our two pulsars,finding that scattering screen distances from Earth for PSRs j0613-0200 and j0636+5128 are 316_(-20)^(+28)pc and 262_(-38)^(+96)pc,*** positions of these scattering screens are coincident with the shell of the Local Bubble towards both *** associations add to the growing evidence of the Local Bubble shell as a dominant region of scattering along many sightlines.

关键词： pulsar interstellar scintillation ionized interstellar medium

同方期刊数据库