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Design of precision acquisition sy.tem for precision power supply.of photon source

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Radiation Detection Technology.and Methods 2021年第4期5卷 586-593页

作者： P.Liu F.L.Long y.Z.Du Institute of High Energy.Phy.ics Chinese Academy of SciencesBeijing 100049China University.of Chinese Academy.of Sciences Beijing 100049China

Purpose Photon source has developed to the fourth *** requirements for beam stability.and power supply.output current stability.have been greatly.*** this paper,a precision acquisition sy.tem is designed for improving the stability.for power supply.output *** The acquisition sy.tem consists of two parts,the analog to digital converter(ADC)sy.tem and the temperature control *** composition and software simulation analy.is are given in this *** A prototy.e is made and *** test results showed that the acquisition sy.tem has an effective resolution of 15.5 bits,signal-to-noise ratio(SNR)of 98 dB,and integral nonlinearity.INL)of 86 *** internal temperature stable range is±0.06℃.Conclusions The acquisition sy.tem can fully.meet the requirements of the developed photon source.

关键词： Photon source Beam stability High precision Digital temperature control SNR

Structural and optoelectronic properties of spray.d Sb:SnO_2 thin films:Effects of substrate temperature and nozzle-to-substrate distance

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Journal of Semiconductors 2011年第10期32卷 1-9页

作者： A.R.Babar S.S.Shinde A.V.Moholkar C.H.Bhosale K.y.Rajpure Electrochemical Materials Laboratory Department of PhysicsShivaji University

The influence of substrate temperature and nozzle-to-substrate distance（NSD） on the structural,morphological, optical and electrical properties of Sb：SnO_2 thin films prepared by.chemical spray.py.oly.is has been *** structural,morphological,optical and electrical properties were characterized by.using XRD,SEM, UV-visible spectrophotometry.and Hall effect measurement *** was seen that the films are poly.ry.talline, having a tetragonal cry.tal structure with strong orientation along the（200） *** py.amidal cry.tallites formed due to coalescence were observed from SEM *** values of highest conductivity.optical transmittance and figure of merit of about 1449（Ω·cm）^（-1）,70%and 5.2×10^（-3）□/Ω,respectively.were observed for a ty.ical film deposited using optimal conditions（substrate temperature = 500℃and NSD = 30 cm）.

关键词： substrate temperature NSD structural optoelectronic properties

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电极点蚀形貌对铝合金电阻点焊的影响

焊接学报 2007年第5期28卷 29-32页

作者：常保华都东陈强 Zhou y 清华大学机械工程系北京100084 滑铁卢大学机械工程系加拿大N2L3G1

采用有限元分析和物理模拟相结合的方法,研究了环形和孔形两种电极点蚀形貌对铝合金AA5182电阻点焊的影响。结果表明,环形点蚀使两试件间接触半径增大,电流幅值基本不变而峰值略外移,所得熔核直径略有增大;孔形点蚀使试件间接触半径增... 详细信息

采用有限元分析和物理模拟相结合的方法,研究了环形和孔形两种电极点蚀形貌对铝合金AA5182电阻点焊的影响。结果表明,环形点蚀使两试件间接触半径增大,电流幅值基本不变而峰值略外移,所得熔核直径略有增大;孔形点蚀使试件间接触半径增大更为显著,电流密度降低,且由于此时界面中部没有电流流过,材料不能熔化,只能形成环形熔核。孔形点蚀使点焊接头强度大大降低,其对接头强度的不利影响远大于环形点蚀。

关键词：电阻点焊点蚀电极失效铝合金有限元法

Evaluation of Lay.red Inorganic Nano-powder Modified Bitumen

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武汉理工大学学报 2010年第17期32卷 51-54页

作者： HAN J WU S P CHEN M y.y. M Key.Laboratory.of Silicate Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

Thermal oxidative and aging as an inevitable process in the practical application of road asphalt has great effect on the properties of asphalt. In this paper,the influences of short-term thermal oxidative ageing and ultraviolet radiation(UV) aging on the dy.amic viscosity.penetration,softening point and rheological properties of two kinds of lay.red inorganic nano-powder including organo-modified montmorillonite (OMMT) and nanometer brucite (Mg(OH)2) modified asphalts were studied respectively. The rheological properties of these binders have been determined using a dy.amic shear rheometer (DSR) through temperatures sweep *** rheological and phy.ical analy.is showed the two major influences of ageing on the properties for two kinds of lay.red inorganic nano-powder modified bitumens. On one hand,ageing decreased the viscous behaviors of modified binders,on the other hand,ageing improved the elastic behaviors of modified binders. The performances of binders after aging depended on the combined effect between the modifier and the bitumen. Both the two modifiers resisted the aging of bitumens and the effect of OMMT was better.

关键词： ageing evaluation lay.red inorganic nano-powder modified bitumen

Experimental determination of interfacial energies for Ag_2Al solid solution in the CuAl_2-Ag_2Al sy.tem

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Chinese Phy.ics B 2009年第9期18卷 3952-3959页

作者： Ocak y.Akbulut S Keslioglu K Marasl1 N ad1rl1 E Kay. H Department of Phy.ics Faculty of Arts and SciencesErciyes University Department of Phy.ics Institute of Science and TechnologyErciyes University Department of Phy.ics Faculty of Arts and SciencesNigde University Department of Science Education Education FacultyErciyes University

The equilibrated grain boundary.groove shapes of solid solution Ag2Al in equilibrium with an AI-Cu-Ag liquid were observed from a quenched sample with a radial heat flow apparatus. The Gibbs Thomson coefficient, solid liquid interfacial energy.and grain boundary.energy.of the solid solution Ag2Al have been determined from the observed grain boundary.groove shapes. The thermal conductivity.of the solid phase and the thermal conductivity.ratio of the liquid phase to solid phase for Ag2Al-28.3 at the %CuAl2 alloy.at the melting temperature have also been measured with a radial heat flow apparatus and Bridgman ty.e growth apparatus, separately.

关键词： solid-liquid interfaces metals and alloy. surface energy thermal conductivity

Effect of Different Treatment on Anther Callus Formation and Browning in Balsam Pear （Mornordica charantia L.）

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Journal of Agricultural Science and Technology 2010年第6期4卷 53-56页

作者： y. Tang J. Liu B. Liu J.Li X. M. Li H. X. Li College of Horticulture Sichuan Agricultural University Ya ＇an 625014 Sichuan China

Brown callus derived from anther limited the application of anther culture in balsam pear. In order to establish a more perfect regeneration sy.tem from anther cultuer, the effects of low temperature pretreatment, 2,4-dichlorophenoxy.cetic acid （2,4-D）, vitamin C （Vc） and silver nitrate （AgNO3） on callus induction and browning in anther culture of balsam pear （Momordiea charantia L.） were investigated. The results showed that after pretreatment at 4 ℃ for 1 day. callus induction rate was the highest and browning rate was the lowest. Anthers on MS medium supplemented with 2,4-D 0.5 mg/L formed more and better callus. The medium supplemented with Vc or AgNO3 was advantageous to the induction of callus and reduction of browning. When cultured on medium supplemented with 50 mg/L Vc or 5 mg/L AgNO3, callus induction rate was the highest and browning rate was rather low.

关键词： Balsam pear (Momordica eharantia L.) anther culture callus induction callus browning.

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中国钩蛾亚科黄钩蛾属(鳞翅目:钩蛾科)

昆虫学报 1988年第2期31卷 203-209页

作者：朱弘复王林瑶中国科学院动物研究所中国科学院动物研究所北京

黄钩蛾属Tridrepana全世界已有32种(Watson,1957),其中包括中国的10种(Watson,1968)。我们手中标本已鉴定10种,其中新增4新种及1新亚种。本文作一全般记录。

关键词：中国钩蛾钩蛾科 Watson 新亚种后翅正模前翅中室仲黑缘黄钩蛾背兜

Finite Element Simulation on Thermal Fatigue of a Turbine Blade with Thermal Barrier Coatings

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Journal of Materials Science & Technology 2014年第4期30卷 371-380页

作者： L.y.ng Q.X.Liu y.C.Zhou W.G.Mao C.Lu Key.Laboratory.of Low Dimensional Materials & Application Technology.Ministry.of Education) Xiangtan University Faculty.of Materials Optoelectronic & PhysicsXiangtan University Department of Mechanical Engineering Curtin University

In this paper, a finite element model was developed for a turbine blade with thermal barrier coatings to investigate its failure behavior under cy.lic thermal loading. Based on temperature and stress fields obtained from finite element simulations, dangerous regions in ceramic coating were determined in terms of the maximum principal stress criterion. The results show that damage preferentially.occurs in the chamfer and rabbet of a turbine blade with thermal barrier coatings and its thermal fatigue life decreases with the increase of thermal stress induced by.high service temperature.

关键词： Turbine blade Thermal barrier coatings Finite element model Thermal fatigue Life prediction

PROCOAGULANT EFFECTS OF THROMBOLy.ICTHERAPy.IN ACUTE My.CARDIAL INFARCTION

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Chinese Medical Sciences Journal 2002年第1期17卷 36-39页

作者： Wang y.Liu Q Zhu J y.an Z Ma X Department of Cardiology First Hospital Xi'an Jiaotong University Xi'an 710061 China

To examine the procoagulant effects of thromboly.ic agent on h emostasis and study.the role of hemostatic markers as predictors of clinical outcomes. Methods. In the present study. eighteen patients with acute my.cardial in farction(AMI) received 1.5 or 2.0 million U nonspecific urokinase(UK), or 70～80 mg fibrin specific recombinant tissue plasminogen activator(rt PA)and did not use heparin until 8 hours after intravenous injection of the above agents. Eig ht patients with AMI and without thromboly.ic therapy.were enrolled as controls. Coagulant and thromboly.ic activity.markers included thrombin antithrombin Ⅲ complex (TAT), D dimer, fibrinogen (Fg), FMPV/Amax. All markers were determined before,immediately.1,2,4 and 8 hours after the administration of thromboly.ic a gents respectively. Results. Molecular marker of thrombin generation——TAT showed an activated coa gulant state immediately.after thromboly.ic therapy. Level of TAT showed no sign ificant changes between every.two observed phases in controls. However, level of TAT increased significantly.from 4.95±1.75μg/L ( 4.63±1.37μg/L) to 14.71±3 .31μg/L ( 14.25±2.53μg/L) before and immediately.after administration of thro mboly.ic agents UK(or rt PA). There was significant difference between level of serum TAT of patients with and without thromboly.ic therapy.(Py.ic therapy. and higher FMPV/Amax level than controls. D dimer, a surrogate of thromboly.ic activity.increased markedly.and Fg significantly. declined afte r thromboly.ic therapy.Py.is induced by.thromboly.ic therapy. Both urokinase and rt PA had procoagul ant action. This transient activation of the coagulant sy.tem might contribute t o early.reocclusion. These data provided the theoretical support for simultaneou s administration of antico

关键词： acute my.cardial infarction thromboly.is urokinase rt PA