检索结果-南通市图书馆

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

High-dose dexamethasone regulates microglial polarization via the gR/JAK1/STAT3 signaling pathway after traumatic brain injury

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第9期20卷 2611-2623页

作者： Mengshi Yang Miao Bai Yuan zhuang Shenghua Lu Qianqian ge Hao Li Yu Deng Hongbin Wu Xiaojian Xu Fei Niu Xinlong Dong Bin zhang Baiyun Liu Beijing Tiantan Hospital Capital Medical UniversityBeijingChina Department of Neurology The First Hospital of Tsinghua UniversityBeijingChina Department of Neurotrauma and Beijing Key Laboratory of Central Nervous System Injury Beijing Neurosurgical InstituteCapital Medical UniversityBeijingChina Department of Critical Care Medicine Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Center for Nerve Injury and Repair Beijing Institute of Brain DisordersChina National Clinical Research Center for Neurological DiseasesBeijingChina

Although microglial polarization and neuroinflammation are crucial cellular responses after traumatic brain injury,the fundamental regulatory and functional mechanisms remain insufficiently *** potent anti-inflammato ry agents,the use of glucoco rticoids in traumatic brain injury is still controversial,and their regulatory effects on microglial polarization are not yet *** the present study,we sought to determine whether exacerbation of traumatic brain injury caused by high-dose dexamethasone is related to its regulatory effects on microglial polarization and its mechanisms of *** vitro cultured BV2 cells and primary microglia and a controlled cortical impact mouse model were used to investigate the effects of dexamethasone on microglial ***,dexamethasone,RU486(a glucocorticoid receptor antagonist),and ruxolitinib(a Janus kinase 1 antagonist)were ***-sequencing data obtained from a C57BL/6 mouse model of traumatic brain injury were used to identify potential targets of *** Morris water maze,quantitative reverse transcription-polymerase chain reaction,western blotting,immunofluorescence and confocal microscopy analysis,and TUNEL,Nissl,and golgi staining were performed to investigate our ***-throughput sequencing results showed that arginase 1,a marker of M2 microglia,was significantly downregulated in the dexamethasone group compared with the traumatic brain injury group at3 days post-traumatic brain *** dexamethasone inhibited M1 and M2 microglia,with a more pronounced inhibitory effect on M2microglia in vitro and in *** receptor plays an indispensable role in microglial polarization after dexamethasone treatment following traumatic brain ***,glucocorticoid receptor activation increased the number of apoptotic cells and neuronal death,and also decreased the density of dendritic spines.A possible downstream receptor signaling mechanism is th

关键词： apoptosis BV2 microglia dexamethasone glucocorticoid receptor glucocorticoids innate immune system microglial polarization neuroinflammation primary microglia traumatic brain injury

Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/CdS heterojunction with photothermal effect for efficient photocatalytic hydrogen production

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.Y.Huang z.Yang S.Y.Yang z.H.Dai Y.J.Liu J.H.Liao g.Y.zhong z.J.Xie Y.P.Fang S.S.zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)MXene/CdS heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)CdS nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of CdS *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure Heterostructure Photothermal effect Photocatalyst Hydrogen evolution

Remarkably high fracture toughness of HfNbTaTizr refractory high-entropy alloy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2022年第28期123卷 70-77页

作者： X.J.Fan R.T.Qu z.F.zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nano Science and Technology Institute University of Science and Technology of ChinaSuzhou 215132China

High-entropy alloys(HEAs)with face-centered cubic(FCC)phase such as CoCrFeMnNi or CoCrNi generally exhibit ultra-high fracture toughness but relatively low *** contrast,body-centered cubic(BCC)HEAs often display higher strengths,but the few reports on fracture toughness measurement demonstrate low toughness *** we show that the BCC HfNbTaTizr refractory HEA,which possesses a combination of high strength,good tensile ductility and excellent high-temperature properties,also exhibits a remarkably high fracture *** using the"single specimen"compliance method for J-integral measurement according to the ASTM E1820–17 standard,its fracture toughness K_(JIC)was experimentally determined to be 210 MPa m^(1/2),which renders this HEA among the toughest metallic *** excellent damage tolerance makes the HEA promising for applications as high-temperature structural materials such as in aerospace field.

关键词： High-entropy alloys BCC structure Fracture toughness J-integral

Survey of the mechanisms of power take-off(PTO)devices of wave energy converters

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2020年第3期36卷 644-658页

作者： z.Liu R.zhang H.Xiao X.Wang School of Engineering RMIT UniversityBundooraVIC 3083Australia

Ocean wave energy conversion as one of the renewable clean energy sources is attracting the research interests of many *** review introduces different types of power take-off(PTO)technology of wave energy *** novelty of this paper is to present advantages and disadvantages of the linear direct and indirect drive PTO devices for ocean wave energy *** designs and optimizations of PTO systems of ocean wave energy converters have been studied from reviewing the recently published *** novel mechanical designs of the PTO systems have been compared and investigated in order to increase the energy harvesting efficiency.

关键词： ocean wave energy

A new scale for optimized cryogenic magnetocaloric effect in ErAl_2@Al_2O_3 nanocapsules

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2018年第5期34卷 848-854页

作者： F.Wei S.Ma L.Yang Y.Feng J.z.Wang A.Hua X.g.zhao D.Y.geng z.D.zhang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

The Er Al2@Al2O3 nanocapsules with Er Al2core and Al2O3 shell were synthesized by modified arc-charge *** typical core-shell structure of the nanocapsules was confirmed by high resolution transmission electron microscopy and X-ray photoelectron *** electron microscopy analysis shows the irregular sphere of the nanocapules with an average diameter of 26 *** investigation revealed the Curie temperature of Er Al2@Al2O3 nanocapsules at 20 K and the typical superparamagnetic behavior between blocking temperature and Curie *** on the blocking temperature and average diameter,the magnetocrystalline anisotropy constant of Er Al2@Al2O3nanocapsules was estimated to illustrate the magnetic contribution to *** large-SMof 14.25 J/（kg K）was obtained under 50 k Oe at 5 K.A vital parameter β was introduced in the present work to scale the optimized magnetic characteristics and the optimized mechanism was discussed in detail according to classical superparamagnetic *** results demonstrate that the optimal-SMwill be obtained when the magnetic parameter β is close to the theoretical coefficient.

关键词： Nanocapsules Magnetocaloric effect Superparamagnetic property Cryogenic refrigeration

Corrosion and cavitation erosion resistance enhancement of cast Ni–Al bronze by laser surface melting

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2022年第2期29卷 359-369页

作者： Q.N.Song Y.Tong H.L.Li H.N.zhang N.Xu g.Y.zhang Y.F.Bao W.Liu z.g.Liu Y.X.Qiao Engineering Research Center of Dredging Technology of Ministry of Education Hohai UniversityChangzhou213022JiangsuChina College of Mechanical and Electrical Engineering Hohai UniversityChangzhou213022JiangsuChina College of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212003JiangsuChina

Laser surface melting (LSM) was applied on a cast Ni–Al bronze (NAB), which was a crucial material for marine ship propellers. A 720 μm-thick LSM layer with fine equiaxed and dendritic microstructures was obtained. After immersion for 30 days, the corrosion rate of cast NAB was reduced by 25% after LSM. Preferential corrosion occurred and deep corrosion pits appeared at α + κIII microstructure for the cast NAB. LSM NAB underwent general corrosion, and a much more protective film formed on the surface because of the homogenized microstructure. The mass loss of the cast NAB was approximately 2.1 times larger than that of LSM NAB after cavitation erosion (CE) in 3.5 wt.% NaCl solution for 5 h. For the two materials, the mechanical impact effect was dominantly responsible for CE damage. Therefore, the improved hardness and homogenized microstructure contributed to the improved CE resistance of LSM NAB. CE destructed the film, shifted the open circuit potential toward a more negative value, and raised the current density by an order of magnitude. Corrosion at the cast eutectoid microstructure and the dendrites of LSM NAB facilitates the degradation under the cavitation attack. CE-corrosion synergy was largely caused by corrosion-enhanced-CE.

关键词： Laser surface melting Ni-Al bronze Microstructure Corrosion Cavitation erosion Synergy

Experimental and numerical study of the effect of pulsatile flow on wall displacement oscillation in a flexible lateral aneurysm model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2019年第5期35卷 1120-1129页

作者： L.z.Mu X.Y.Li Q.z.Chi S.Q.Yang P.D.zhang C.J.Ji Y.He g.gao School of Energy and Power Engineering Dalian University of TechnologyDalian 116024China School of Biomedical Engineering Capital Medical UniversityBeijing 100069China The First Affiliated Hospital of University of Science and Technology of China Hefei 230036China

This study experimentally and numerically investigated the effect of pulsatile flow of different frequencies and outflow resistance on wall deformation in a lateral aneurysm.A method for constructing a flexible aneurysm model was developed,and a self-designed piston pump was used to provide the pulsatile flow conditions.A fluid-structure interaction simulation was applied for comparison with and analysis of experimental *** maximum wall displacement oscillation increased as the pulsation frequency and outflow resistance increased,especially at the aneurysm *** is an obvious circular motion of the vortex center accompanying the periodic inflow fluctuation,and the pressure at the aneurysm dome at peak flow increased as the pulsatile flow frequency and terminal flow resistance *** results could explain why abnormal blood flow with high frequency and high outflow resistance is one of the risk factors for aneurysm rupture.

关键词： Lateral aneurysm In vitro experiment Pulsatile flow Wall displacement oscillation Fluid-structure interaction simulation

Particle shape characterisation and classification using automated microscopy and shape descriptors in batch manufacture of particulate solids

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2016年第1期14卷 61-68页

作者： Yang zhang Jing J. Liu Lei zhang Jorge Calderon De Anda Xue z. Wang School of Chemistry and Chemical Engineering South China University of Technology 381 Wushan Road Guangzhou 510641 China School of Bioscience and Bioengineering South China University of Technology Guangzhou Higher Education Mega Centre Panyu District Guangzhou510006 China Institute of Particle Science and Engineering School of Chemical and Process Engineering University of Leeds Leeds I52 9JT UK

It is known that size alone, which is often defined as the volume-equivalent diameter, is not sufficient to characterize many particulate products. The shape of crystalline products can be as important as size in many applications, Traditionally, particulate shape is often defined by several simple descriptors such as the maximum length and the aspect ratio. Although these descriptors are intuitive, they result in a loss of information about the original shape. This paper presents a method to use principal component analysis to derive simple latent shape descriptors from microscope images of particulate products made in batch processes, and the use of these descriptors to identify batch-to-batch variations. Data from batch runs of both a laboratory crystalliser and an industrial crystallisation reactor are analysed using the described approach. Qualitative and quantitative comparisons with the use of traditional shape descriptors that have nhwical meanings and Fourier shape descriptors are also made.

关键词： Batch-to-batch variation Classification Principal components analysis Shape descriptors