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上海航天 1989年第3期6卷 58-60页

作者： A Saha Deuri anil K.Bhownick 居建国

在我们较早的论文中,已经报导了以乙烯一丙烯二烯烃橡胶(EPDM)为基的一种新的固体推进剂火箭绝热层的配方和降解.此化合物满足绝热所需的所有技术性能.但是,绝热层的工艺尚未详细研究.为了对此化合物作现场实验,研究了成型压力、冷却速... 详细信息

在我们较早的论文中,已经报导了以乙烯一丙烯二烯烃橡胶(EPDM)为基的一种新的固体推进剂火箭绝热层的配方和降解.此化合物满足绝热所需的所有技术性能.但是,绝热层的工艺尚未详细研究.为了对此化合物作现场实验,研究了成型压力、冷却速率及固化温度对技术性能和溶胀特性的影响.

关键词：固体火箭绝热层工艺试验

Applications of k-covers

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Acta Mathematica Sinica,English Series 2006年第4期22卷 1151-1160页

作者： g.DI MAIO Ljubisa D.R.KOCINAC Enrico MECCARIELLO Dipartimentodi Matematica Seconda Università di NapoliVia Vivaldi 4381100 CasertaItalia Faculty of Sciences and Mathematics University of NisVisegradska 3318000 NisSerbia Facoltàdi Ingegneria Università del SannioPalazzo B.LucarelliPiazza Roma82100 BeneventoItalia

We investigate a role of k-covers in selection principles theory. Some results about relationships between Ramsey theory and game theory and selection principles that involve k-covers are also given.

关键词： selection principles,ω-cover γ-cover k-cover Hurewicz property k-groupability k-weak groupability game theory

The guest Star of AD185 must have been a Supernova

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Chinese Journal of Astronomy and Astrophysics 2006年第5期6卷 635-640页

作者： Fu-Yuan Zhao R. g. Strom Shi-Yang Jiang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 ASTRON Radiosterrenwacht Postbus 2 7990 AA Dwingeloo The Netherlands and Astronomical Institute University of Amsterdam Kruislaan 403 1098 SJ Amsterdam The Netherlands

The ＂guest star＂ of AD185, recorded in the ancient Chinese history the Houhanshu, has been widely regarded as a supernova. However, some authors have suggested that the guest star might have been a comet. It has also been proposed that the record is the concatenation of a nova with a comet made by an early compiler. We have checked the record of the guest star, comparing it with records of comets in the same history. We find that most descriptions of comets clearly indicate motion, whereas the record of the guest star does not. We further argue that the term ＂yan＂ used to describe the star＇s ＂size＂ might be short for yanchuang （seat bed）, and ＂half a yan＂ would be simply as an imaginary figuration of the ancient observer. Moreover, we show that the term ＂hou -year＂（hou-nian） most probably means the year after next. We argue that the asterism Southern gate consisted of the stars α andβ Cen. We conclude that the record describing the guest star of AD 185 is completely different from any comet record in the same history, and that it almost certainly was a supernova.

关键词： history of astronomy -- guest star -- stars supernova individual (SN185)

Optimizing power oscillations in an ellipsometric system

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Chinese Optics Letters 2018年第3期16卷 48-52页

作者： Manoel P. Araújo Stefano De Leo gabriel g. Maia Institute of Physics Cleb Wataghin State University of Campinas Campinas 13083-872 Brazil Department of Applied Mathematics State University of Campinas Campinas 13083-250 Brazil

Ellipsometry is a powerful and well-established optical technique used in the characterization of materials. It works by combining the components of elliptically polarized light in order to draw information about the optical system. We propose an ellipsometric experimental set-up to study polarization interference in the total internal reflection regime for gaussian laser beams. The relative phase between orthogonal states can be measured as a power oscillation of the optical beam transmitted through a dielectric block, and the orthogonal components are then mixed by a polarizer. We show under which conditions the plane wave analysis is valid, and when the power oscillation can be optimized to reproduce a full pattern of oscillation and to simulate quarter- and half-wave plates.

关键词： Optimizing power oscillations in an ellipsometric system

Long-range attractive forces extending from alumina nanofiber surface

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International Journal of Smart and Nano Materials 2014年第3期5卷 133-151页

作者： Leonid A.Kaledin Fred Tepper Tatiana g.Kaledin Argonide Corporation 291 Power CourtSanfordFL 32771USA

Aluminum oxide-hydroxide nanofibers,2 nm in diameter and approximately 250 nm long,are electroadhesively grafted onto glass microfibers,therefore forming a macroscopic assembly of alumina nanofibers on the second solid in highly organized *** assembly can be viewed as a straight cylinder with rough surface and charge density of approximately 0.08 C/m^(2).This creates a significant electric field with negligible screening(ka≪1)in the region close to the surface of the *** field attracts nano-and micron-size particles from as far as 0.3 mm in less than a few seconds,many orders of magnitude greater than the conventional Derjaguin–Landau–Verwey–Overbeek theory that predicts only nanometer-scale effects arising from the presence of the *** strong electric field on the surface is then able to retain particles such as micron-size powdered activated carbon as well as much smaller particles such as fumed silica nanoparticles of 10–15 nm in diameter,viruses,atomically thick sheets of graphene oxide,latex spheres,RNA,DNA,proteins,and dyes.

关键词： alumina nanofibers electric double layer electrostatic adsorption

Long-term stability of transparent n/p ZnO homojunctions grown by rf-sputtering at room-temperature

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Journal of Materiomics 2019年第3期5卷 428-435页

作者： V.Kampylafka A.Kostopoulos M.Modreanu M.Schmidt E.gagaoudakis K.Tsagaraki V.Kontomitrou g.Konstantinidis g.Deligeorgis g.Kiriakidis E.Aperathitis Microelectronics Research group Institute of Electronic Structure and LaserFoundation for Research and TechnologydFORTH-HellasP.O.Box 1385Heraklion70013CreteGreece Tyndall National Institute-University College Cork Lee MaltingsDyke ParadeCorkIreland Physics Department University of CreteP.O.Box 220871003HeraklionCreteGreece Transparent Conductive Materials&Devices group Institute of Electronic Structure&LaserFoundation for Research and Technology FORTH-HellasP.O.Box 1385Heraklion70013CreteGreece

ZnO-based n/p homojunctions were fabricated by sputtering from a single zinc nitride target at room temperature on metal or ITO-coated glass and Si substrates.A multi-target rf-sputtering system was used for the growth of all oxide films as multilayers in a single growth run without breaking the vacuum in the growth *** nitrogen-containing films(less than 1.5 at.% of nitrogen)were n-type ZnO when deposited in oxygen-deficient Ar plasma(10%O_(2))and p-type ZnO when deposited in oxygen-rich Ar plasma(50%O_(2)).The all-oxide homojunction ITO/n-ZnO/p-ZnO/ITO/glass was fabricated in a single deposition run and exhibited visible transparency in the range of 75-85%.The n/p ZnO homojunctions,having metallic contacts,formed on conventionally processed substrates showed a fairly unstable behavior concerning the current-voltage ***,the same homojunctions formed on Si_(3)N_(4)-patterned substrates and stored in atmosphere for a period of five months were stable exhibiting a turn-on voltage of around 1.5 *** realization of a room temperature sputtered transparent and stable ZnO homojunction paves the way to the realization of all-oxide transparent optoelectronic devices.

关键词： ZnO homojunction p-type ZnO Single step sputtering Stability Patterned substrate

微生物添加剂对青贮高粱发酵品质和稳定性的影响

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中国农业科学 2002年第11期35卷 1401-1405页

作者：管武太,g.Ashbell,Y.Hen,Z.g.Weinberg 华南农业大学动物科学学院动物营养与饲料科学系 Forage Preservation and By-products Research Unit The Volcani Center Forage Preservation and By-products Research Unit The Volcani Center Forage Preservation and By-products Research Unit The Volcani Center 广州510642 Bet Dagan50250 Israel Bet Dagan50250 Israel Bet Dagan50250 Israel

将蜡熟期收获的全株高粱 (cultivarFS5 )切割成长度约 2cm ,用 1.5LWeck玻璃发酵罐在实验室条件下进行青贮试验。试验分 3组 ,第 1组为对照 ,第 2、第 3组分别为添加微生物添加剂的A和B组。 2种微生物添加剂的添加水平均为 2× 10 5CFU... 详细信息

将蜡熟期收获的全株高粱 (cultivarFS5 )切割成长度约 2cm ,用 1.5LWeck玻璃发酵罐在实验室条件下进行青贮试验。试验分 3组 ,第 1组为对照 ,第 2、第 3组分别为添加微生物添加剂的A和B组。 2种微生物添加剂的添加水平均为 2× 10 5CFU·g-1DM。在青贮后的第 2、4、8、15和 6 0天每处理随机取 3罐打开并采样以研究其发酵动力学的变化 ,其中第 6 0天的青贮料还用于测定发酵品质 ,并同时进行连续 5d的稳定性测定。结果表明 ,2种微生物添加剂均加快青贮pH下降速度 ,且乳酸产量增加。与对照相比 ,2种微生物添加剂使青贮料在暴露空气后产生的CO2 量略有增高 ,葡萄糖损失较多。微生物添加剂并不影响青贮料灰分和粗蛋白含量 (P >0 .0 5 ) ,但明显降低乙酸 (P <0 .0 5 )、丁酸 (P <0 .0 1)和丙酸 (P <0 .0 1)含量 ,显著提高乳酸含量 (P <0 .0 1)。A组青贮料DM含量较低 ,暴露空气后酵母含量较多。B组青贮料DM含量 (P <0 .0 5 )和乳酸含量 (P <0 .0 1)较高 ,而乙酸含量最低 (P <0 .0 5 )。添加剂B明显降低了ADF (P <0 .0 1) ,ADL(P <0 .0 5 )和NDF (P <0 .0 5 )含量。本试验结果显示 ,乳酸菌添加剂可加快高粱的发酵过程 ,但可能对开窖后的稳定性有不利影响。

关键词：高粱青贮料微生物添加剂

Stathmin as a surrogate marker of phosphatidylinositol-3-kinase pathway activity:Towards precision medicine in HPV-negative head&neck squamous cell carcinoma

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genes & Diseases 2022年第3期9卷 820-825页

作者： Andrew T.Turk Dario garcia-Carracedok David T.Kent Elizabeth Philipone Juana Maria garcia-Pedrero Salvatore M.Caruana Lanny g.Close gloria H.Su Department of Pathology and Cell Biology and Columbia UniversityNew YorkNY 10032USA Department of Otolaryngology Columbia UniversityNew YorkNY 10032USA Department of Otolaryngology Vanderbilt UniversityNashvilleTN 37232USA Department of Otolaryngology Hospital Universitario Central de Asturias and Instituto Universitario de Oncologia Del Principado de AsturiasOviedo 33006Spain

In order to assess Stathmin as an immunohistochemical(IHC)indicator of phosphatidylinositol 3-kinase(PI3K)pathway activity in HPV-negative head&neck squamous cell carcinoma(HNSCC),we compared Stathmin IHC to expression of other pathway *** also evaluated the relationship between Stathmin IHC and the mutational status of four key pathway ***,we ascertained whether Stathmin IHC correlates with tumor grade or primary *** exists between high Stathmin expression and high pAKT1 expression,indicating a role for Stathmin IHC as a marker of pathway *** analysis did not show correlation between Stathmin IHC and mutation of the four genes *** also observed an association between high Stathmin expression and oropharyngeal primary *** results suggest utility of Stathmin IHC as an indicator of PI3K pathway activity,and thereby demonstrate potential relevance of Stathmin IHC in the context,of HNSCC.

关键词： Cancer Head&neck squamous cell carcinoma Pathology Stathmin

Analysis of CO_2 utilization into synthesis gas based on solar thermochemical CH_4-reforming

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Journal of Energy Chemistry 2019年第1期28卷 61-72页

作者： Bachirou guene Lougou Yong Shuai gédéon Chaffa Huang Xing Heping Tan Huibin Du School of Energy Science and Engineering Harbin Institute of Technology Key Laboratory of Aerospace Thermophysics of MIIT Harbin Institute of Technology Laboratory of Energetics and Applied Mechanics (LEMA) Polytechnic College of Abomey-Calavi Abomey-Calavi University College of Metallurgy and Energy North China University of Science and Technology College of Management and Economics Tianjin University

In this study, the solar thermochemical reactor performance for CO_2 utilization into synthesis gas(H_2+ CO) based on CH_4 reforming process was investigated in the context of carbon capture and utilization(CCU) technologies. The P1 radiation heat transfer model is adopted to establish the heat and mass transfer model coupled with thermochemical reaction kinetics. The reactor thermal behavior with direct heat transfer between gaseous reactant and products evolution and the effects of different structural parameters were evaluated. It was found that the reactor has the potential to utilize by ～60% of CO_2 captured with 40% of CH_4 co-fed into syngas(72.9% of H_2 and 27.1% of CO) at 741.31 k W/mof incident radiation heat flux. However, the solar irradiance heat flux and temperature distribution were found to significantly affect the reactant species conversion efficiency and syngas production. The chemical reaction is mainly driven by the thermal energy and higher species conversion into syngas was observed when the temperature distribution at the inner cavity of the reactor was more uniform. Designed a solar thermochemical reactor able to volumetric store concentrated irradiance could highly improve CCU technologies for producing energy-rich chemicals. Besides, the mixture gas inlet velocity, operating pressure and CO_2/CH_4 feeding ratio were crucial to determining the efficiency of CO_2 utilization to solar fuels. Catalytic CO_2-reforming of CH_4 to chemical energy is a promising strategy for an efficient utilization of CO_2 as a renewable carbon source.

关键词： Thermochemical reactor CO2 utilization Radiation flux and temperature distribution CH4-reforming Syngas