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Electron Field Emission from Different sp3 Content Diamond-Like Carbon Films

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Chinese Physics Letters 1999年第2期16卷 152-154页

作者： MAO Dong-sheng ZHAO Jun LI Wei WANG Xi liu xiang-huai ZHU Yu-kun ZHOU Jiang-yun FAN Zhong LI Qiong XU Jing-fang Ion Beam Laboratory Shanghai Institute of MetallurgyChinese Academy of SciencesShanghai 200050 Department of Electronics Science and Technology East China Normal UniversityShanghai 200062

Different sp^(3) content diamond-like carbon films are deposited on to highly n-doped Si(111)substrates by a new plasma deposition technique-filtered arc *** electron field emission properties are studied by using a simple diode *** is showed that the turn-on field is decreased and field emission current density is increased with the increasing sp3 content(75-80%,80-83%,and 88-90%)of the *** emission current of 0.1μA from the three samples was detected under the electric field of 10.1,5.6,and 2.9 V/μm and emission current density of 4.4,15.2,and 43.2μA/cm^(2),respectively,under 14.3 V/μ***-Nordheim(F-N)plots of the three samples nearly show of lineaity indicating that electron field emission obeys F-N theory.

关键词： structure. deposition. theory.

Growth of Biaxially Textured Yttria-Stabilized Zirconia Thin Films on Si(lll) Substrate by Ion Beam Assisted Deposition

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Chinese Physics Letters 2000年第3期17卷 221-223页

作者： MU Hai-Chuan REN Cong-Xin JIANG Bing-Yao DING Xing-Zhao YU Yue-Hui WANG Xi liu xiang-huai ZHOU Gui-En JIA Yun-Bo Ion Beam Laboratory Shanghai Institute of MetallurgyChinese Academy of SciencesShanghai 200050 Structure Research Laboratory University of Science and Technology of ChinaHefei 230026

The(001)oriented yttria-stabilized zirconia(YSZ)Hlms with in-plane biaxial texture have been deposited on Si(111)substrates by ion beam assisted deposition at ambient *** effects of ion/atom arrival rate fatio(R=(Ar^(+)+O2^(+))/ZrO_(2))and incident angle of bombarding ion beam on the Him texture development were *** was found that the in-plane biaxial texture of the films was improved gradually with increasing ion/atom arrival rate ratio R up to a critical value 1,9,but it was degraded with the further increase of *** optimal in-plane biaxial texture,whose full width at half maximum of the(111)4>-scan spectrum is 14°,can be obtained at R=1.9 and incident angle of 55°.For a fixed R,the optimal crystallinity and in-plane biaxial alignment of the YSZ Hlms did not appear at the same incident angle and showed an opposite variation with the change of the incident angle from 51°to 55°.C-axis alignment(perpendicular to substrate surface)does not show any substantial variation with the change of incident angle within the range of 47°-56°.

关键词： temperature. incident alignment

Field Observation and Analysis of Wave-Current-Sediment Movement in Caofeidian Sea Area in the Bohai Bay, China

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China Ocean Engineering 2014年第3期28卷 331-348页

作者：左利钦陆永军汪亚平刘怀湘 State Key Laboratory of Hydrology Water Resources and Hydraulic EngineeringNanjing Hydraulic Research Institute School of Geographic and Oceanographic Sciences Nanjing University

In order to study the mechanism of flow-sediment movement, it is essential to obtain measured data of water hydrodynamic and sediment concentration process with high spatial and temporal resolution in the bottom boundary layer （BBL）. Field observations were carried out in the northwest Caofeidian sea area in the Bohai Bay. Near 2 m isobath （under the lowest tidal level）, a tripod system was installed with AWAC （Acoustic Wave And Current）, ADCP （Acoustic Doppler Current Profilers）, OBS-3A （Optical Backscatter Point Sensor）, ADV （Acoustic Doppler Velocimeters）, etc. The accurate measurement of the bottom boundary layer during a single tidal period was carried out, together with a long-term sediment concentration measurement under different hydrological conditions. All the measured data were used to analyze the characteristics of wave-current-sediment movement and the BBL. Analysis was performed on flow structure, shear stress, roughness, eddy viscosity and other parameters of the BBL. Two major findings were made. Firstly, from the measured data, the three-layer distribution model of the velocity profiles and eddy viscosities in the wave-current BBL are proposed in the observed sea area; secondly, the sediment movement is related closely to wind-waves in the muddy coast area where sediment is clayey silt： 1） The observed suspended sediment concentration under light wind conditions is very low, with the peak value generally smaller than 0.1 kg/m^3 and the average value being 0.03 kg/m^3; 2） The sediment concentration increases continuously under the gales over 6-7 in Beaufort scale, under a sustained wind action. The measured peak sediment concentration at 0.4 m above the seabed is 0.15-0.32 kg/m^3, and the average sediment concentration during wind-wave action is 0.08-0.18 kg/m^3, which is about 3-6 times the value under light wind conditions. The critical wave height signaling remarkable changes of sediment concentration is 0.5 m. The results show that the suspended

关键词： field observation wave-induced sediment suspension wave-current interaction bottom boundary layer (BBL) Caofeidian Bohai Bay

Porous Structures and Short-Wavelength Photoluminescence of C^(+)-Implanted SiO_(2) Films

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Chinese Physics Letters 1999年第5期16卷 361-363页

作者： ZHAO Jun MAO Dong-sheng DING Xing-zhao LIN Zi-xin JIANG Bing-yao YU Yue-hui YANG Gen-qing liu xiang-huai S.Jin H.Bender Ion Beam Laboratory Shanghai Institute of MetallurgyChinese Academy of SciencesShanghai 200050 State Key Laboratory of Transducer Technology Shanghai Institute of MetallurgyChinese Academy of SciencesShanghai 200050 IMEC KapeldreefB-3001LeuvenBelgium

C ions of three different energies were sequentially implanted into SiO_(2) films grown by plasma enhanced chemical vapor *** of the samples were studied with transmission electron microscopy(TEM)and secondary ion mass spectroscopy As revealed by cross-sectional TEM,porous structures had been created in the implanted region during ion *** photoluminescence(PL)was detected from the as-implanted ***,intense short-wavelength PL peaking at 360-370nm and ~450nm was observed from the annealed *** blue light from samples excited by an Xe lamp can be observed by naked eyes at room *** light emission mechanisms are briefly discussed.

关键词： temperature. deposition. sectional

Discrepancy between presumptive and definite causes of chronic cough

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Chinese Medical Journal 2011年第24期124卷 4138-4143页

作者： YU Li QIU Zhi-hong WEI Wei-li liu Bo XU xiang-huai LU Han-jing QIU Zhong-min Department of Respiratory Medicine Tongji Hospital TongjiUniversity School of Medicine Shanghai 200065 China

Background The current diagnostic algorithms for chronic cough require the establishment of the primary presumptive causes followed by the confirmation of diagnosis with the specific therapies. The aim of the study was to investigate the discrepancy between presumptive and definite causes and its clinical implication. Methods A total of 109 patients with chronic cough underwent laboratory investigations to identify the cause of cough; including sinus computerized tomography （if needed）, histamine bronchial provocation, induced sputum cytology and 24-hour esophageal pH or multi-channel intraluminal impedance combined with pH monitoring. The presumptive causes were confirmed by treating them sequentially. The difference between presumptive and definite causes of chronic cough was compared. Results Single cause was more frequent in the definite diagnosis than in the presumptive diagnosis （78.9% vs. 54.1%, X2=15.01, m=-0.0001）. In contrast, multiple causes were significantly fewer in definite diagnosis than in the presumptive diagnosis （15.6% vs. 37.6%, X2=13.53, P=-0.0002）. There was a discrepancy between definite and presumptive causes in 30 patients （27.5%）. Compared with the presumptive causes, definite upper airway cough syndrome （24.8% vs. 11.9%, X^2=6.0, P=0.01） and gastroesophageal reflux disease （6.4% vs. 0, X2=7.23, P=0.007） was more frequent as a single cause of chronic cough while cough variant asthma plus gastroesophageal reflux disease （3.7% vs. 11.9%, X2=5.17, P=0.02） and upper airway cough syndrome plus nonasthmatic eosinophilic bronchitis （0 vs. 9.2%, X2=10.48, P=0.001） were fewer as multiple causes of chronic cough. Conclusions A discrepancy was common between presumptive and definite causes of chronic cough. To treat presumptive causes sequentially may be a suitable solution for avoidance of erroneous multiple causes and possible over-treatment.

关键词： chronic cough etiology algorithm

Visual electrophysiological assessment of children with poor response to treatment for functional amblyopia

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 315-322页

作者： Dong-Qing Yuan Wei-Wei Zhang liu-Wei Gu Qing-huai liu Department of Ophthalmology Jiangsu Province Hospitalthe First Affiliated Hospital of Nanjing Medical UniversityJiangsu Women and Children Health HospitalNanjing 210029Jiangsu ProvinceChina

AIM:To assess the visual electrophysiological outcomes in children with functional amblyopia who exhibited poor response to conventional ***:Twenty-one children with functional amblyopia,aged 5.7±2.1y(range:4-10y),underwent comprehensive ophthalmic and refractive *** domain-optical coherence tomography(SD-OCT)and multifocal electroretinography(mfERG)were conducted to analyze the macular retinal thickness and the first-order response P1 ring of the mfERG in the amblyopic eye(AE)compared to the fellow good eye(GE).RESULTS:Initially,visual acuity in the AE ranged from 20/800 to 20/40,while the GE exhibited a range of 20/25 to 20/20(P<0.01).After 6mo of treatment,17 patients demonstrated improved visual acuity in the AE to 20/50 or better,while 4 children showed no ***-OCT revealed comparable macular and optic disc structures between the AE and *** to treatment,the mfERG P1 ring amplitude was significantly reduced in the AE compared to GE(P<0.05).The AE/GE ratio of P1 ring amplitude showed significant improvement ***,a smaller AE/GE ratio before treatment was associated with poorer improvement ***:In the management of functional amblyopia,a thorough assessment of amblyopic eye examinations is *** 20%of amblyopic eyes may not achieve significant improvement in visual acuity,despite the absence of detectable organic retinal *** may reveal underlying *** mfERG into initial assessments or treatment follow-ups can aid in identifying potential hidden retinal defects and predicting the prognosis of the amblyopic eye.

关键词： functional amblyopia poor response optical coherence tomography multifocal electroretinography retinal defects

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典型河网形态特征与分布

水利学报 2007年第11期38卷 1354-1357页

作者：刘怀湘王兆印清华大学水利水电工程系北京100084

河流网络系统是地表流水地貌的重要组成部分,具有开放性、随机性、自相似性等特点。不同地区具有其独特的自然环境条件,从而形成了各种外观上迥然不同的河网形态。本文以卫星地图上的平面拓扑结构为依据,划分了3种典型河网形态:羽状河... 详细信息

河流网络系统是地表流水地貌的重要组成部分,具有开放性、随机性、自相似性等特点。不同地区具有其独特的自然环境条件,从而形成了各种外观上迥然不同的河网形态。本文以卫星地图上的平面拓扑结构为依据,划分了3种典型河网形态:羽状河网、叶状河网和枝状河网,并在Horton定律的基础上对这3种典型河网形态的平均Horton比和流域外型参数进行了定量统计分析。此外,进行了中国大陆范围内各种典型河网形态的分布研究,从而探讨了影响河网形态产生的环境条件。

关键词：河网形态 Horton定律分支比长度比面积比

Predefined-Time Constrained Optimization of Multi-Agent Systems Under Impulsive Effects

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IEEE/CAA Journal of Automatica Sinica 2025年第1期12卷 255-257页

作者： Zhuyan Jiang Xiaoyang liu xiang Jiang Jinde Cao the School of Computer Science and Technology Jiangsu Normal University IEEE the School of Mathematics Southeast University

Dear Editor,This letter investigates predefined-time optimization problems(OPs) of multi-agent systems(MASs), where the agent of MASs is subject to inequality constraints, and the team objective function accounts for impulse effects. Firstly, to address the inequality constraints,the penalty method is introduced. Then, a novel optimization strategy is developed, which only requires that the team objective function be strongly convex.

关键词： Constrained optimization

Effect of pouring time on microstructure and mechanical properties of centrifugal cast Ti-46Al alloy tubes

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China Foundry 2025年第1期22卷 65-74页

作者： Gang Huang Qian Dang Cong-cong Su Jing Zhao Chi Zhang Guo-huai liu Zhao-dong Wang The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

The grain size of TiAl alloy castings prepared by traditional casting process is coarse,thus showing poor mechanical *** this study,a new type of high performance Ti-46Al alloy tube prepared by vacuum centrifugal casting technology was *** research comprehensively examined the influence of pouring time on the microstructure and mechanical performance of the castings,employing both experimental approaches and ProCast simulation *** findings indicate that prolonging the pouring time facilitates a microstructural evolution from coarse columnar grains to refined equiaxed *** the condition of pouring temperature of 1,600℃,rotation speed of 800 r·min^(-1) and pouring time of 6 s,the tensile strength of Ti-46Al alloy at room temperature reaches 650 MPa,and the tensile strength at 800℃ reaches 705 MPa,which is significantly higher than that of traditional as-cast Ti-Al alloy.

关键词： vacuum induction melting centrifugal casting Ti-46Al alloy pouring time Ti-Al alloy tubes

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