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变压器 1965年第6期 28-32页

作者： w.维特曼王仲甫

高压电器其空处理所用的真空装置,根据要求的不同,其真空度约在10～10-4托尔（Torr）之间。所用的真空度越高,在薄的纸绝缘层中的残余气体就越低。本文研究了绝缘层特别厚时的最合适的真空度问题。

关键词：真空度捐失气体分子平均自由行程绝缘层蒸汽压力含水量汽压热力学函数含水率真空除气真空处理气体穿透

3-D discontinuum numerical modeling of subsidence incorporating ore extraction and backfilling operations in an underground iron mine in China

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International Journal of Mining Science and Technology 2017年第2期27卷 191-201页

作者： Huang Gang Kulatilake Pinnaduw. H.S.w. Shreedharan Srisharan Cai Sijing Song Hongqing School of Resources and Environmental Engineering Wuhan University of Technology School of Civil and Environmental Engineering University of Science and TechnologyBeijing Rock Mass Modeling and Computational Rock Mechanics Laboratories University of Arizona

An underground iron mine in China has been used as a case-study to research the subsidence due to ore extraction and backfilling during open stoping operations. A 3-D discontinuum numerical model w.s built incorporating geologic complexities including faults and interfaces betw.en different lithologies,and the stoping and backfilling sequence adopted from the mine plans. The stoping w.s carried out in tw. vertically stacked horizontal layers, w.th a total of 16 stopes. Large displacements of up to 50 cm w.re observed along the roof of the stopes, and a maximum surface subsidence of 22.5 cm w.s *** w.s found to eliminate subsequent displacements and subsidence. The extraction of the upper orebody w.s found to influence displacements in the low.r orebody. Finally, a subsidence profile w.s constructed to show.the subsidence at all locations along the length of the surface and region of influence on the surface.

关键词： Underground iron mine Discontinuum numerical modeling Open stoping Backfill Subsidence

Mass spectrometry detection of basic drugs in fast chiral analyses w.th vancomycin stationary phases

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Journal of Pharmaceutical Analysis 2018年第5期8卷 324-332页

作者： Hongyue Guo M.Farooq w.hab Alain Berthod Daniel w.Armstrong Department of Chemistry and Biochemistry University of Texas at Arlington Institut des Sciences Analytiques CNRS Université de Lyon 1

Current trends in chiral analysis of pharmaceutical drugs are focused on faster separations and higher separation efficiencies, Core-shell or superficially porous particles （SPP） based chiral stationary phases （CSPs） provide reduced analysis times w.ile maintaining high column efficiencies and sensitivity. In this study, mobile phase conditions suitable for chiral analyses w.th electrospray ionization LC-MS w.re systematically investigated using vancomycin as a representative CSP. The performance of a 2.7 μm SPP based vancomycin CSP （SPP-V） 10 cm ×0.21 cm column w.s compared to that of a corresponding 5 μm fully porous particles based analogue column. The results demonstrated that the SPP-V column provides higher efficiencies, 2-5 time greater sensitivity and shorter analysis time for a set of 22 basic pharma- ceutical drugs. The SPP-V w.s successfully applied for the analysis of the degradation products of racemic citalopram w.ose enantiomers could be selectively identified by MS.

关键词： Mass spectrometry detection Chiral separation Basic drugs Beta-blockers Superficially porous particle Fully porous particle Fast separation Vancomycin

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地震解释中的测井资料和虚测井资料

石油物探译丛 1990年第6期 63-67页

作者： w. Michael Cline 谢凤兰

在不能使用声速和密度测井资料的情况下,利用虚声速和虚密度测井资料来生成合成地震记录具有许多优点。地震解释中最基本和最关键的步骤是把地震资料同地质信息(即:记录层位/断层等)联系起来。不合适的深时转换将会在解释和绘图过程中... 详细信息

在不能使用声速和密度测井资料的情况下,利用虚声速和虚密度测井资料来生成合成地震记录具有许多优点。地震解释中最基本和最关键的步骤是把地震资料同地质信息(即:记录层位/断层等)联系起来。不合适的深时转换将会在解释和绘图过程中产生错误的结果。

关键词：地震解释测井资料虚测井资料

HEAT TRANSFER ANALYSIS DURING ROLLING OF THIN SLAB IN CSP

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Acta Metallurgica Sinica(English Letters) 2006年第4期19卷 244-250页

作者： w.F. w. Y.H. Feng X.X. Zhang Inner Mongolia University of Science and Technology Baotou 014010 China University of Science and Technology Beijing Beijing 100083 China

A mathematical model has been built to numerically predict the thermal history of thin slab during CSP （compact strip process） rolling. To estimate the temperature distribution in the slab mare accurately, the mathematical model combines heat transfer in the slab, in the roll, and at the roll-slab interface during bite. The numerical results agree w.th on-site running data, w.ich proves the reliabili~, of the mathematical model. The results show.that roll chilling has a significant effect on the temperature distribution in the slab.

关键词： numerical simulation heat transfer CSP(compact strip process) rolling thermal process

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胃泌素的生理和病理生理学

国际外科学杂志 1988年第3期 161-164页

作者： Mulholland M. w. 金山

胃泌素是外科医师最为熟悉的胃肠道内分泌,几十年前已了解到其调节胃酸分泌的功能,但近期对胃泌素的合成、合成后的分子加工、壁细胞的胃泌素受体以及其分子学水平的作用提出了新的重要见解.新的强力抗胃泌素药物正在制备中.为此,作者... 详细信息

胃泌素是外科医师最为熟悉的胃肠道内分泌,几十年前已了解到其调节胃酸分泌的功能,但近期对胃泌素的合成、合成后的分子加工、壁细胞的胃泌素受体以及其分子学水平的作用提出了新的重要见解.新的强力抗胃泌素药物正在制备中.为此,作者简略总结胃泌素的合成、加工和生物学作用.合成和加工胃泌素是分子结构已肯定的第一个胃肠道内分泌.虽然Edkins于1906年首次由胃窦组织提炼出胃泌素,其纯化和肽的化学特性到1964年才由Gregory等阐明,过去几年对胃泌素分子的合成和加工逐有详细的了解.胃泌素编码的基因已自人体DNA中分离出.人体胃泌素基因长约4100碱基对,涉及101个氨基酸

关键词：胃泌素瘤胃酸分泌壁细胞泌酸细胞胃泌素受体神经切除术迷走神经切断术病理学病理生理学

施用石灰对马铃薯产量及土壤pH、Al、Mn和Ca的影响

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园艺与种苗 1984年第4期 19-22页

作者： w. van Lierop 徐崇敬

在加拿大魁北克省,马铃薯(Solanum tuberosum L.)几乎全部种植在粗质土壤上。这些土壤通常高度灰化,有机物极少且酸性又强。人们都不愿往这类土壤中施用石灰,因为普遍认为这会引起马铃薯疮痂病,从而降低其市场价值。不过由于土壤pH低,... 详细信息

在加拿大魁北克省,马铃薯(Solanum tuberosum L.)几乎全部种植在粗质土壤上。这些土壤通常高度灰化,有机物极少且酸性又强。人们都不愿往这类土壤中施用石灰,因为普遍认为这会引起马铃薯疮痂病,从而降低其市场价值。不过由于土壤pH低,植株有效Mn

关键词：马铃薯土豆茄属块茎产量 Mn Al pH Ca

Cross-Polarized GPR Imaging of Fracture Flow.Channeling

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Journal of Earth Science 2015年第6期26卷 776-784页

作者： Georgios P.Tsoflias Christopher Perll Matthew.Baker Matthew.w.Becker Department of Geology the University of Kansas Chesapeake Energy Marathon Oil Corporation California State University Long Beach

Ground penetrating radar（GPR） can be used to image fractures and monitor fluid flow.in the subsurface. Conventional GPR imaging uses single-polarization, co-polarized acquisition. w. examine the use of cross-polarized GPR signals for imaging flow.channeling in a discrete horizontal fracture. Numerical modeling（FDTD） demonstrates that w.en the fracture channel is oriented at an oblique angle to the survey line, depolarization of the GPR signal results in scattered energy along the cross-polarized components. w.en the channel is oriented parallel or orthogonal to the survey line, all scattered energy is captured by the co-polarized components and no signal is present in the cross-polarized orientation. Multipolarization, time-lapse 3D GPR field data w.re acquired at the Altona Flat Rock test site in New.York State. The GPR surveys w.re conducted during background fresh fracture w.ter conditions and during a natural gradient saline tracer test w.ich w.s used to highlight flow.channels along a sub-horizontal fracture. Amplitude analysis of the cross-polarized data reveals flow.channeling that is in agreement w.th the co-polarized GPR images and w.th independent hydraulic tests. This investigation demonstrates that cross-polarized components of GPR signals can be used to enhance imaging of flow.channels in fractured media.

关键词： GPR single-polarization cross-polarized data rapid flow saline tracer fractured rock.

Low.melting point MCP-69, MCP-96, MCP-137, and MCP-200 alloys for radiation protection in radiological and therapeutic processes

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Radiation Medicine and Protection 2022年第4期3卷 175-182页

作者： Michael w.Perrigin Kendall A.w.lliams Brandon K.w.ight Malaika Maqbool Emily Caffrey Remo George Ghafar Ali Muhammad Maqbool Health Physics Program Department of Clinical&Diagnostic SciencesThe University of Alabama at BirminghamBirminghamAL 35294USA Nuclear Medicine and Molecular Imaging Sciences Program Department of Clinical&Diagnostic SciencesThe University of Alabama at BirminghamBirminghamAL 35294USA iomedical Sciences Program Department of Clinical&Diagnostic SciencesThe University of Alabama at BirminghamBirminghamAL 35294USA Nanomaterials Research Group Physics DivisionPINSTECHIslamabadPakistan

Objective To evaluate the low.melting-point MCP-69,MCP-96,MCP-137,and MCP-200 alloys,and characterize them for their potential to protect from the harms associated w.th radiation and eliminate radiation hazards during radiological procedures and treatment of *** The Klein-Nishina formula w.s used to calculate the electronic and atomic cross-sections of these alloys using photon beams w.th energies 4,6,9,12,and 18*** transfer coefficients,Compton mass attenuation coefficient,mass-energy transfer coefficient,and recoil energy of electrons in the specific photon energies of 4–18MeV w.re *** alloys'effective charge number and the photon energy w.re key factors in determining the properties found by utilizing the Klein-Nishina formula and Compton *** The cross sections and energy transfer coefficients increased w.th the increasing effective charge number Z of the alloys and decreased as the photon energy *** Compton recoil of the ejected electrons w.s observed to have a direct relationship w.th photon energy,but mass-energy transfer decreased w.th increasing photon *** alloys can replace the toxic lead for environmentally cleaned radiation *** These calculations and characteristics of the MCP alloys can help further determine their viability as materials for radiation shielding,their use in safe cancer diagnosis,treatment,and environmental hazards protection.

关键词： MCP alloys Klein-Nishina formula Cross-sections Radiation shielding Safe cancer diagnosis and treatment

Carrier Density and Plasma Frequency of Alummum Nanofilms

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Journal of Materials Science & Technology 2003年第4期19卷 365-367页

作者： HaoDU JunGONG ChaoSUN RongfangHUANG lISHIw.N w.Y.Cheung S.P.w.ng InstituteofMetalResearch ChineseAcademyofSciencesShenyang110016China TheChinsesUniversityofHongKong HongKongChina

In this w.rk, the prerequisite and mode of electromagnetic response of Al nanof ilms to electromagnetic w.ve field w.s suggested. Reflectance, transmittance in infrared region and carrier density of the films w.s measured. w.th the carrier density of the films, the dependence of their plasma frequencies on the film thickness w.s obtained. On the other hand, the dependence of absorptance on the frequency of electromagnetic w.ve field w.s set up by using the measured reflectance and transmittance, w.ich provided plasma frequency-film thickness relation as w.ll. Similarity of both plasma frequency-film thickness relations proved plasma resonance as a mode of electromagnetic response in Al nanofilms.

关键词： Aluminum nanofilm Electromagnetic response Size effect