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Theory of electron emission in High Fields from Atomically Sharp emitters:*** of the Fowler-Nordheim model

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云南大学学报（自然科学版） 1992年第S1期14卷 67-75页

作者： Jun He,p. H. Cutler, N. m. miskovsky, T. e. Feuchtwang Department of physics, The pennsylvania State University 104 Davey Laboratory, Universitypark, pA 16802andt. e. Sullivan Departrnent of electrical engineering, Temple University, philadelphia, pA 19122

Field emission from metallic emitter tips is generally described by the Fowl-er-Nordheim theory, which is based on a planar model of the tip with a classical imagecorrection. Within the free electron model and the WKB approximation, the planar tipmodel leads to the well-known Fowler-Nordheim cquation. The form of this equationpredicts that a plot of log J/ F^2 versus 1/F; where J is the current density and F,

关键词： Fowler electron metallic emitter planar Sharp correction versus curvature sharp

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Brillouin and Raman Scattering of Fluid and Solid Hydrogen at High pressures and Temperatures

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Brillouin and Raman Scattering of Fluid and Solid Hydrogen a...

无创产前筛查对高龄孕妇胎儿21-三体综合征的诊断价值

18th International Conference on High pressure Science and Technology

作者： K.matsuishi e.Gregoryanz H.K.mao R.J.Hemley Institute of materials Science University of TsukubaTsukubaIbaraki 305-8573Japan Geophysical Laboratory and Center for High-pressure Research Carnegie Institution of Washington5251 Broad Branch RoadNWWashingtonD.C 20015USA Geophysical Laboratory and Center for High-pressure Research Carnegie Institution of Washington5251 Broad Branch RoadNWWashingtonD.C 20015USA Geophysical Laboratory and Center for High-pressure Research Carnegie Institution of Washington5251 Broad Branch RoadNWWashingtonD.C 20015USA

＜正＞ most of studies on fluid and solid hydrogen havebeen carried out at and below room temperatureexcept for those by shock compression. The p-Vequation of state （eOS） of solid hydrogen has beenobtained experimentally up to 150 Gpa at roomtemperature. However, the p-V-T eOS of hydrogenderived from static compression experiments isavailable only for the fluid state in p≤2 Gpa andt≤300 K. The eOS and the behaviors of vibron athigher pressures and temperatures are needed inorder to discuss the intermolecular interaction and

关键词： Hydrogen Brillouin Scattering Raman Scattering High pressure High Temperature

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中国优生与遗传杂志 2020年第10期28卷 1199-1201页

作者：符桂丹王兰芳陈华符琼娥临高县人民医院检验科海南临高571800 海口市中医医院检验科海南海口570203 临高县人民医院妇产科海南临高571800

目的分析无创DNA产前检测(NIpT)技术在筛查高龄孕妇21-三体综合征的临床应用价值。方法选择2016年3月至2019年3月在我院门诊行NIpT检查的6912例高龄孕妇为研究对象,染色体异常高风险孕妇再经羊膜腔穿刺确诊,并将两种分析方法的结果符合... 详细信息

目的分析无创DNA产前检测(NIpT)技术在筛查高龄孕妇21-三体综合征的临床应用价值。方法选择2016年3月至2019年3月在我院门诊行NIpT检查的6912例高龄孕妇为研究对象,染色体异常高风险孕妇再经羊膜腔穿刺确诊,并将两种分析方法的结果符合情况进行比较。结果 6912例孕妇经NIpT筛查出染色体异常高风险173例(2.50%)。筛查出21-三体综合征、18-三体综合征、13-三体综合征高风险分别为62例(0.90%)、31例(0.45%)、17例(0.25%),性染色体异常高风险33例(0.48%)和其他常染色体异常高风险30例(0.43%)。70.21%的NIpT阳性高龄孕妇经染色体核型分析确诊,其阳性预测值分别为21-三体综合征100.00%、18-三体综合征62.96%、13-三体综合征26.67%、性染色体异常52.63%、其他常染色体异常45.45%.但ppT对21-三体综合征具有有较高的准确性和敏感性,但对性染色体与13-三体综合征检测具有较大局限性。高龄孕妇可选择NIpT为主要筛查手段,以提高对染色体异常患儿的诊断效能。

关键词：高龄无创DNA产前检测染色体核型分析

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亚碲酸铋Bi_2TeO_5单晶的化学计量比的研究

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人工晶体学报 2000年第S1期29卷 52-页

作者： A.peter 1, I.Fldvari 1,L.pppl 2, R.S.Klein 3 (1.Research Institute for Solid State physics and Optics,Hungarian Academy of Sciences,1121 Budapest XII, Konkoly Thege ut 29 33,1525 Budapest p.O.B.49,Hungary 2.Institute of Inorganic and Analytic

Bismuth tellurite Bi 2TeO 5 is a novel nonlinear crystal with interesting physical *** crystal structure belongs to the mm 2 symmetry and can be described as 2 3 1 fluorite type superstructure,derived from a hypothetically ordered totally oxidized Bi 2TeO 6 *** lattice contains 17% open oxygen positions and cation coordination sites between 5 and *** material,therefore is an excellent host for several dopants with segregation coefficients close to *** most interesting feature of the crystal is a long living(years)photorefractive signal that developed in the four wave mixing process without specific *** feature enables the application of the crystal as hologram recording material. Single crystals of Bi 2TeO 5 can be grown by the Czochralski *** of the key problem of the growth process is the control of the stoichiometry of the *** high vapor pressure of TeO 2 at the melting point results in the nonstoichiometric evaporation of the melt and by altering the initial Bi 2O 3/TeO 2 creates continuously shifted melt *** 550℃ and 700℃ the oxidation state of Bi 2TeO 5 may be modified,since the fully oxidized Bi 2TeO 6 compound is thermodynamically stable in this *** grown from the melt at 906℃,depending on the post growth period(annealing and cooling down processes)might be partly or fully oxidized.

关键词： bismuth tellurite single crystal stoichiometry CZ method

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Antibacterial effects of ethanolic extract of Zehneria scabra on Quails Artificially Infected with Salmonella enteritidis

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Journal of pharmacy and pharmacology 2021年第11期9卷 387-396页

作者： Herman m.F Biekop marc K Kouam Vivian Yengeh Gabriel T Kamsu Bridget Katte Alexis Teguia Biekop Herman Department of Animal Science Faculty of Agronomy and Agricultural SciencesPO BOX 188DschangCameroon Center for Research on Filariases and other Tropical Diseases(CRFilmT) P.O.Box 5797YaoundéCameroon microbiology and Antimicrobial Substances Research Unit Faculty of ScienceUniversity of DschangCameroon 不详

Antimicrobial use in livestock is faced with various challenges including emergence of antimicrobial resistance and presence of drug residues in meat products,hence the need for *** aim of this work was to assess the effect a plant(Zehneria scabra)extract on Salmonella infected quails,as an alternative to antibiotic *** were randomly assigned into six groups each containing twelve *** neutral control(T0)group was not infected and received tap water whereas other groups were *** negative control(T-)received tap *** positive control(T+)received a single dose of oxytetracycline(20 mg/kg).T1,T2 andt3 orally received the plant extract at the following respective doses:9,18 and 37 mg/*** were infected by oral administration of a single dose of Salmonella enteritidis(10^(5)CFU).Haematological and biochemical parameters were *** day 2 to day 9 to day 16,the bacterial load of all treatment groups(T+,T1,T2,T3)*** infection resulted in a significant(pease in serum levels of alanine aminotransferase,triglycerides,total cholesterol and white blood cells,and a significant decrease in the liver and kidney protein *** treatment resulted in the correction of the aforementioned *** plant extract(18 mg/kg)is as effective as oxytetracycline,and can be safely used in phytomedicine for the treatment of Salmonella enteritidis infection without kidney and liver damage.

关键词： Zehneria scabra Salmonella enteritidis antisalmonellal activity quails