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电学性质在研究玻璃析晶过程中的应用

上海建材学院学报 1995年第3期 193-202页

作者：黄文(曰山) C.S.Ray d.e.day 上海建材学院材料工程系 department of Ceramic engineering and Graduate Center for Materials Research University of Missouri-Rolla Rolla MO 65401 U.S.A.

测定了Li2O·2SiO2玻璃在不同的核化和晶化条件下的介电常数ε,介电损耗tgδ和电阻率ρ。测试结果表明: ε, tgδ,与ρ均由试样的析晶率所决定;试样在不同温度T_n下核化3 h,然后在660℃温度下晶化15 min,其ε,tgδ与ρ均是核化温度下T_... 详细信息

测定了Li2O·2SiO2玻璃在不同的核化和晶化条件下的介电常数ε,介电损耗tgδ和电阻率ρ。测试结果表明: ε, tgδ,与ρ均由试样的析晶率所决定;试样在不同温度T_n下核化3 h,然后在660℃温度下晶化15 min,其ε,tgδ与ρ均是核化温度下T_n的函数,将1/ε对T_n作图,获得的曲线类似于核化速率温度曲线。

关键词：玻璃的核化与晶化电学性质实验方法

玻璃纤维增强热塑性有机复合材料界面强度及其对材料力学性能的影响

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材料科学进展 1992年第4期6卷 363-368页

作者：王树海 M.N.Rahaman d.e.day 山东工业陶瓷研究设计院 University of Missouri-Rolla USA

本文研究了 BK-10玻璃纤维增强聚甲基丙烯酸甲酯和聚碳酸酯两种热塑性有机基复合材料中纤维与基体界面强度的测量、控制及其对复合材料性能的影响。用有机硅烷耦联剂涂覆纤维表面可以提高纤维与基体的界面强度并相应提高复合材料的力学... 详细信息

本文研究了 BK-10玻璃纤维增强聚甲基丙烯酸甲酯和聚碳酸酯两种热塑性有机基复合材料中纤维与基体界面强度的测量、控制及其对复合材料性能的影响。用有机硅烷耦联剂涂覆纤维表面可以提高纤维与基体的界面强度并相应提高复合材料的力学性能。实验发现四种基体纤维界面破坏形式分别存在于界面强度强和弱的韧性和脆性基体复合材料体系中。选用折光率相匹配的基体和纤维,适当控制制备工艺可以制备出光学透明的复合材料。

关键词：复合材料界面断裂玻璃纤维

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氮化磷酸盐玻璃化学稳定性的研究

玻璃搪瓷与眼镜 1988年第3期 1-9页

作者：黄文旵 d.e.day MO 65401.USA Materials Research Center University of Missouri-Rolla 西北轻工业学院

与硅酸盐玻璃相比较,磷酸盐玻璃具有较高的热膨胀系数和较低的软化温度,可以作为与不锈钢、铜,以及合金铝形成气密性封接的理想材料。但是,具有高热膨胀系数(α=180～240×10;/℃)的磷酸盐玻璃的化学稳定性较差,极易受水侵蚀,这就限制... 详细信息

与硅酸盐玻璃相比较,磷酸盐玻璃具有较高的热膨胀系数和较低的软化温度,可以作为与不锈钢、铜,以及合金铝形成气密性封接的理想材料。但是,具有高热膨胀系数(α=180～240×10;/℃)的磷酸盐玻璃的化学稳定性较差,极易受水侵蚀,这就限制了它的实际应用。然而,只要适当调整组成,就可以提高它的化学稳定性。据报道,有些磷酸盐玻璃的耐

关键词：氮化处理溶解速度侵蚀过程活化能不同温度激活能热力学函数化学稳定性耐化学性

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用差热分析测定玻璃析晶过程的核化速率曲线

上海建材学院学报 1993年第3期6卷 187-195页

作者：黄文旵 C.S.Ray d.e.day 上海建材学院 department of Ceramic engineering and GradLlate Center for Materials Research University of Missouri-Rolla

本方法通过对玻璃试样 dTA 数据的处理,改进了玻璃晶化过程中成核速率随温度变化曲线的测定方法。此法比用光学显微镜,对试样中可见晶粒进行计数的传统方法,更快速而简便。本实验确认,Li_2O·2SiO_2玻璃的成核速率曲线(I-T)和晶体生长... 详细信息

本方法通过对玻璃试样 dTA 数据的处理,改进了玻璃晶化过程中成核速率随温度变化曲线的测定方法。此法比用光学显微镜,对试样中可见晶粒进行计数的传统方法,更快速而简便。本实验确认,Li_2O·2SiO_2玻璃的成核速率曲线(I-T)和晶体生长速度曲线(U-T)不重叠。该系统的 dTA 曲线中,晶体放热峰的高度δT可看成是试样中晶核数量的大小。实验还证明,在确定成核温度范围和成核速率达最大值的最佳温度方面,峰高δT随温度变化的曲线可以代替成核速率 I 随温度变化的曲线。由固体相变理论推出的结论,证明了本实验方法的可行性。

关键词：玻璃成核差热分析

Converting TRex-RGB green-channel data to 557.7 nm auroral intensity:Methodology and initial results

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earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang d.M.Gillies e.Spanswick e.F.donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region explorer(TRex)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TRex-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TRex mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TRex spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TRex-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TRex-RGB data *** methodology established in this study will also be applicable to the upcoming SMILe ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TRex RGB green-line aurora auroral transport model

The multi-impurity system in CdSe nanoplatelets:electronic structure and thermodynamic properties

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Communications in Theoretical Physics 2024年第3期76卷 165-173页

作者： d A Baghdasaryan V A Harutynyan e M Kazaryan H A Sarkisyan Russian-Armenian University H Emin 1230051YerevanArmenia Institute of Applied Problems of Physics 25 Nersisyan St0014YerevanArmenia

This paper theoretically studies the impurity states and the effects of impurity concentration and configuration on the optical,electrical,and statistical properties of CdSe nanoplatelets(NPLs).An image charge-based model of electron-impurity interaction is *** charge-carrier energy spectra and corresponding wave functions depending on the impurity number and configuration are *** electron binding energies are calculated for different NPL *** is shown that the image charge-based interaction potential that arises due to the dielectric constants mismatch is much stronger than the interaction potential that does not take such a mismatch into ***,it is demonstrated that the binding energies are increasing with the number of *** calculate the canonical partition function using the energy levels of the electron,which in turn is used to obtain the mean energy,heat capacity,and entropy of the non-interacting electron *** thermodynamic properties of the non-interacting electron gas that depend on the geometric parameters of the NPL,impurity number,configuration,and temperature are studied.

关键词： nanoplateletes thermodynamic properties impurity states

Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： K.d.James J.e.Cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTeCs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTeC heterogeneity by examining the mechanisms by which mTeCs mimic the peripheral self[1].

关键词： medullary eliminate restricted

Simple collective model for nuclear chiral mode

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Frontiers of physics 2024年第2期19卷 1-5页

作者： R.V.Jolos e.A.Kolganova d.R.Khamitova Joint Institute for Nuclear Research 141980 DubnaMoscow regionRussia dubna State University 141982 DubnaMoscow RegionRussia

A simple semi-analytical collective model that takes into account the limitations of the variation interval of the collective variable is suggested to describe the chiral dynamics in triaxial odd−odd nuclei with a fixed particle−hole *** collective Hamiltonian is constructed with the potential energy obtained using the postulated ansatz for the wave function symmetric with respect to chiral *** diagonalizing the collective Hamiltonian the wave functions of the lowest states are obtained and the evolution of the energy splitting of the chiral doublets in transition from chiral vibration to chiral rotation regime is demonstrated.

关键词： collective model nuclear chiral

The 2024 Compendium of Physical Activities and its expansion

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Journal of Sport and Health Science 2024年第1期13卷 1-2,F0003页

作者： Stephen d.Herrmann erik A.Willis Barbara e.Ainsworth Kansas Center for Metabolism and Obesity Research University of Kansas Medical CenterKansas CityKS 66160USA Center for Health Promotion and disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA School of exercise and Health Shanghai University of SportShanghai 200438China

First developed 30 years ago,the Compendium of Physical Activities(Compendium)was created to provide a standardized way of measuring and classifying specific physical activities(PAs),allowing researchers and health professionals to assess the energy expenditure and health benefits associated with different PA.1Since its inception,the Compendium has been widely utilized and recognized as a fundamental PA and health resource.

关键词： has utilized classify