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低温气相硅外延前氩微波等离子原位溅射清洗对薄膜界面的损伤

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真空科学与技术 1995年第2期15卷 113-117页

作者：叶志镇 z.zhou R.Reif 浙江大学高纯硅国家重点实验室杭州310027 美国麻省理工学院

本文研究了在超高真空低温CVD（chemicalvapordeposition）硅外延中，ECR（electroncyclotronresonance）微波等离子原位溅射清洗对外延层界面损伤的情况。超高分辨透射电镜（TEM）照片表明，界面引起的损伤是较严重的，损伤层的宽度与... 详细信息

本文研究了在超高真空低温CVD（chemicalvapordeposition）硅外延中，ECR（electroncyclotronresonance）微波等离子原位溅射清洗对外延层界面损伤的情况。超高分辨透射电镜（TEM）照片表明，界面引起的损伤是较严重的，损伤层的宽度与衬底偏压的高低和溅射时间的长短直接相关。

关键词：低温硅外延溅射清洗界面损伤薄膜界面

Processes and mechanisms of desertification in northern China during the last 30 years,with a special reference to the Hunshandake Sandy Land,eastern Inner Mongolia

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Processes and mechanisms of desertification in northern Chin...

中国科学院地质与地球物理研究所2007学术年会

作者： X.Yang ~*,z.Ding,X.Fan,z.zhou,N.Ma Institute of Geology and Geophysics,Chinese Academy of Sciences,P.O.Box 9825,Beijing 100029,China

Desertification has been widely recognized as one of the most serious environmental problems in China,although its concept and causes are still debated in scientific *** semi-arid region in northeastern China,located on northern margin of eastern Asian summer monsoon,is ideal for investigating the processes and mechanisms of desertification because of its very sensitive *** the Hunshandake Sandy Land of eastern Inner Mongolia,a former dormant dunes and wetlands environment,we monitored the variation of the desertified land and the wetlands in order to assess the climatic and human impacts on the processes of *** research methods included digital image processing of LANDSAT data and ground *** remote sensing data from the last three decades show that the wetlands were larger in 1975 and 1992 than in 1989 and *** variation of the extension of mobile dunes is in inverse proportion to that of *** main process of desertification is the reactivation of dormant sand *** changes of wetlands and desertified lands correlate considerably well with the variations of local precipitation and temperature,suggesting that climate might be the key factor triggering desertification in the *** other sandy lands of China,however,human activities might be the key factor causing desertification and land degradation.

关键词： Desertification Semi-arid region Landscape evolution Remote sensing China

提出一种基于深度学习的方法改进胸部CT扫描肺结节的诊断准确性

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国际医学放射学杂志 2022年第1期 115-116页

作者： Y.W.Wang J.W.Wang S.X.Yang L.L.Qi H.L.Lin z.zhou 常俊琦

摘要目的比较胸部CT上基于深度学习（DL）的和放射科医生的对肺部结节诊断的效能。方法纳入150个由放射科医师评估、报告且经病理证实的肺结节（60%为恶性）。

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HVOF热喷涂制备Fe基非晶合金涂层的微观结构和摩擦磨损性能研究

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热喷涂技术 2017年第4期9卷 50-57页

作者： H.H.Yao z.zhou K.z.Tang z.Tan G.H.Wang D.Y.He 王玉北京理工大学材料科学与工程学院

通过高速氧燃料火焰喷涂制备一种Fe59Cr12Nb5B20Si4非晶金属涂层,与商用316L不锈钢相比,以实现更低的热导率和更好的耐磨防护效果。所制备的涂层具有致密层状结构(孔隙率小于1%),有轻微的氧化发生。Fe基涂层的微观结构中具有非晶骨架并... 详细信息

通过高速氧燃料火焰喷涂制备一种Fe59Cr12Nb5B20Si4非晶金属涂层,与商用316L不锈钢相比,以实现更低的热导率和更好的耐磨防护效果。所制备的涂层具有致密层状结构(孔隙率小于1%),有轻微的氧化发生。Fe基涂层的微观结构中具有非晶骨架并有纳米晶析出,其热导率(2.66 W/m K)显著低于不锈钢涂层(5.87 W/m K)。得益于这种微观结构,涂层硬度可达到1258±92 HV。因为涂层磨损机理的改变,涂层的摩擦系数和磨损量在200℃时上升,并在400℃时下降。涂层在室温时的磨损机理主要为疲劳磨损并伴有氧化磨损。在200℃时,由于第三粒的磨损,磨损过程加速。400℃下涂层耐磨性能的下降可能导致大面积的氧化膜的生成。

关键词：摩擦磨损性能合金涂层微观结构非晶制备 HVOF Fe 热喷涂

Dixon MRI对健康成年人背部伸肌年龄和性别相关变异的多参数定量评估

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国际医学放射学杂志 2024年第2期 247-248页

作者： P.z.Chen z.zhou L.Sun X.K.Yu K.Li J.Li 王俊

摘要目的使用Dixon MRI研究健康成人年龄相关性背伸肌退变的性别差异，并分析肌肉定量参数与背肌力的关系。方法纳入105名健康受试者行腰椎Dixon MRI检查。量

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Current reduction in a pseudo-breakup event:THEMIS observations

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Current reduction in a pseudo-breakup event:THEMIS observati...

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： z.H.Yao z.Y.Pu C.J.Owen S.Y.Fu X.N.Chu J.Liu V.Angelopoulos I.J.Rae C.Yue X.-z.zhou Q.-G.zong X.Cao Q.Q.Shi C.Forsyth A.M.Du Institute of Geology and Geophysics Chinese Academy of Sciences Mullard Space Science Laboratory UCL School of Earth and Space Sciences Peking University Department of Earth Planetaryand Space SciencesUniversity of California Department of Atmospheric and Oceanic Sciences University of California Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsShandong University

Pseudo-breakup events are thought to be generated by the same physical processes as *** paper reports on the cross-tail current reduction in an isolated pseudo-breakup observed by three of the THEMIS probes(THEMIS A(THA),THEMIS D(THD),and THEMIS E(THE))on 22 March *** this pseudo-breakup,several localized auroral intensifications were seen by ground-based *** the unique spatial configuration of the three THEMIS probes,we have estimated the inertial and diamagnetic currents in the near-Earth plasma sheet associated with flow braking and *** found the diamagnetic current to be the major contributor to the current reduction in this pseudo-breakup *** flow braking,the plasma pressure was reinforced,and a weak electrojet and an auroral intensification *** flow braking/diversion,the electrojet was enhanced,and a new auroral intensification was *** peak current intensity of the electrojet estimated from ground-based magnetometers,.7 × 10 A,was about 1 order of magnitude lower than that in a typical *** suggest that this pseudo-breakup event involved two dynamical processes:a current-reduction associated with plasma compression ahead of the earthward flow and a current-disruption related to the flow braking/*** processes are closely connected to the fundamental interaction between fast flows,the near-Earth ambient plasma,and the magnetic field.

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Aerosol particles, tobacco smoke, crude oil, coffee roasting and industrial processes: Analysis of complex materials, thermal processes and aerosols by Photo-Ionisation Mass Spectrometry(PIMS)

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Aerosol particles, tobacco smoke, crude oil, coffee roasting...

2018年中国质谱学术大会（CMSC2018）

作者： R.zimmermann S.Ehlert J.Heide M.R.Saraji-Bozorgzad A.Walte T.Streibel C.Grimmer H.Czech X.Li L.Li z.zhou J.Schade R.Irsig J.Passig Joint Mass Spectrometry Center of Helmholtz zentrum München and University of Rostock Institute of Mass Spectrometry and Atmospheric Environment Jinan University

Mass Spectrometry with soft Photo-Ionisation(PIMS)1 enables the direct detection of trace molecules in complex organic vapours as well as in pyrolysis or combustion off-gases. This renders PIMS to a well suited tool for Evolved Gas Analysis(EGA) in Thermal Analysis(TA), for detection of the molecular organic signatures of desorption, pyrolysis and combustion processes as well as for applied and fundamental combustion research. In the lecture a brief explanation of the principles of the used photo-ionisation mass spectrometry approaches is given(multi-and single-photon ionisation). In the following the hyphenations of TA-devices to PIMS analysers are presented(e.g. thermogravimetry-PIMS) and applications such as crude oil-analysis are discussed. PIMS also allow the direct monitoring of combustion and pyrolysis processes, e.g. for industrial process monitoring purposes or more fundamental combustion studies. For example the formation of flavour compounds during the coffee roasting process or the formation of toxic compounds form wood combustion or cigarette smoking can be addressed. In summary the potential of soft photo-ionisation mass spectrometry for applied industrial-as well as fundamental-research is demonstrated and discussed. In a second part, the application of photo ionization mass spectrometry for on-line detection of the composition of individual aerosol particles is addressed. The so called aerosol time-of flight mass spectrometry(ATOF) or single particle mass spectrometry(SPAMS) approach uses laser desorption/ionization to generate negative and positive ions(elemental cations, complex cations and anions), mainly from the inorganic bulk of individual airborne aerosol particles of 0.2-20 μm diameter. A SPAMS system of HEXIN Inc. has been equipped with a Photonion GmbH excimer laser and was applied to detect trace emissions of ships using residual fuel using V as tracer. A new development enables the SPAMS approach to detect both, inorganic toxic compounds,

关键词： photo ionization mass spectrometry on-line monitoring of gases and aerosol particles

Polyethylene glycol fusion repair of severed rat sciatic nerves reestablishes axonal continuity and reorganizes sensory terminal fields in the spinal cord

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Neural Regeneration Research 2025年第7期20卷 2095-2107页

作者： Emily A.Hibbard Liwen zhou Cathy z.Yang Karthik Venkudusamy Yessenia Montoya Alexa Olivarez George D.Bittner Dale R.Sengelaub Program in Neuroscience Indiana UniversityBloomingtonINUSA Department of Neuroscience University of Texas at AustinAustinTXUSA

Peripheral nerve injuries result in the rapid degeneration of distal nerve segments and immediate loss of motor and sensory functions;behavioral recovery is typically *** used a plasmalemmal fusogen,polyethylene glycol(PEG),to immediately fuse closely apposed open ends of severed proximal and distal axons in rat sciatic *** have previously reported that sciatic nerve axons repaired by PEG-fusion do not undergo Wallerian degeneration,and PEG-fused animals exhibit rapid(within 2–6 weeks)and extensive locomotor ***,our previous report showed that PEG-fusion of severed sciatic motor axons was non-specific,i.e.,spinal motoneurons in PEG-fused animals were found to project to appropriate as well as inappropriate target *** this study,we examined the consequences of PEG-fusion for sensory axons of the sciatic *** adult male and female rats(Sprague–Dawley)received either a unilateral single cut or ablation injury to the sciatic nerve and subsequent repair with or without(Negative Control)the application of *** action potentials recorded immediately after PEG-fusion repair confirmed conduction across the injury *** success of PEG-fusion was confirmed through Sciatic Functional Index testing with PEG-fused animals showing improvement in locomotor function beginning at 35 days *** 2–42 days postoperatively,we anterogradely labeled sensory afferents from the dorsal aspect of the hindpaw following bilateral intradermal injection of wheat germ agglutinin conjugated horseradish ***-fusion repair reestablished axonal *** to unoperated animals,labeled sensory afferents ipsilateral to the injury in PEG-fused animals were found in the appropriate area of the dorsal horn,as well as inappropriate mediolateral and rostrocaudal ***,despite having intact peripheral nerves,similar reorganizations of labeled sensory afferents were also observed contralateral to the injury and repa

关键词： axotomy dorsal horn peripheral nerve injury plasticity polyethylene glycol(PEG) sciatic nerve sensory terminals wheat germ agglutinin horseradish peroxidase

Polyethylene glycol has immunoprotective effects on sciatic allografts, but behavioral recovery and graft tolerance require neurorrhaphy and axonal fusion

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Neural Regeneration Research 2025年第4期20卷 1192-1206页

作者： Tyler A.Smith Liwen zhou Cameron L.Ghergherehchi Michelle Mikesh Cathy z.Yang Haley O.Tucker JuliAnne Allgood Jared S.Bushman George D.Bittner Department of Molecular Biosciences University of Texas at AustinAustinTXUSA Department of Neuroscience University of Texas at AustinAustinTXUSA Division of Pharmaceutical Sciences University of WyomingLaramieWYUSA

Behavioral recovery using(viable)peripheral nerve allografts to repair ablation-type(segmental-loss)peripheral nerve injuries is delayed or poor due to slow and inaccurate axonal ***,such peripheral nerve allografts undergo immunological rejection by the host immune *** contrast,peripheral nerve injuries repaired by polyethylene glycol fusion of peripheral nerve allografts exhibit excellent behavioral recovery within weeks,reduced immune responses,and many axons do not undergo Wallerian *** relative contribution of neurorrhaphy and polyethylene glycol-fusion of axons versus the effects of polyethylene glycol per se was unknown prior to this *** hypothesized that polyethylene glycol might have some immune-protective effects,but polyethylene glycol-fusion was necessary to prevent Wallerian degeneration and functional/behavioral *** examined how polyethylene glycol solutions per se affect functional and behavioral recovery and peripheral nerve allograft morphological and immunological responses in the absence of polyethylene glycol-induced axonal ***-type sciatic nerve injuries in outbred Sprague–Dawley rats were repaired according to a modified protocol using the same solutions as polyethylene glycol-fused peripheral nerve allografts,but peripheral nerve allografts were loose-sutured(loose-sutured polyethylene glycol)with an intentional gap of 1–2 mm to prevent fusion by polyethylene glycol of peripheral nerve allograft axons with host *** to negative control peripheral nerve allografts not treated by polyethylene glycol and in contrast to polyethylene glycol-fused peripheral nerve allografts,animals with loose-sutured polyethylene glycol peripheral nerve allografts exhibited Wallerian degeneration for all axons and myelin degeneration by 7 days postoperatively and did not recover sciatic-mediated behavioral functions by 42 days *** morphological signs of rejection,such as col

关键词： allograft rejection axotomy macrophage myelin nerve repair polyethylene glycol(PEG) sciatic nerve T cell transplantation Wallerian degeneration