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桩撑式支护基坑通用弹性地基梁分析法

广东工业大学学报 2024年第2期41卷 37-43页

作者：史宏彦涂彬鸿杨德森广东工业大学先进制造学院广东揭阳515548

弹性地基梁法常用于模拟分析桩撑(锚)式支护基坑在开挖、设撑等施工工况中变形和受力的变化。目前利用该方法对某工况基坑分析时,首先要将整个支护桩在支撑处划分为若干个桩段,然后利用相邻桩段交界处的位移连续条件和受力平衡条件,推... 详细信息

弹性地基梁法常用于模拟分析桩撑(锚)式支护基坑在开挖、设撑等施工工况中变形和受力的变化。目前利用该方法对某工况基坑分析时,首先要将整个支护桩在支撑处划分为若干个桩段,然后利用相邻桩段交界处的位移连续条件和受力平衡条件,推导出相应的待定参数方程,之后再利用求出的待定参数分析支护体系(基坑)的变形和受力。由于不同施工工况对应的支撑数和桩段数不同,因此该方法必须根据不同工况重新推导各自的参数方程,从而导致计算过程繁杂,难以形成通用计算公式和方法,也不易编程等问题。通过将支撑与桩段归纳为3种基本连接形式(即支撑分别相连于桩顶、相邻两桩段之间和坑底),本文建立了相邻两个桩段间待定参数的递推公式,进而推导出了适用于内支撑和锚索支撑形式、任意支撑道数、开挖或设撑工况的通用待定参数方程。该方程仅含4个参数,远少于现有方法且易于求解。文中算例结果验证了本文方法的合理性和可行性。

关键词：深基坑桩撑(锚)式支护体系弹性地基梁法施工过程变形和受力通用分析方法

Electrochemical formation of La-Al intermetallic compounds in fluoride melts

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Rare Metals 2023年第9期42卷 3170-3176页

作者： Ping Pan shi-hong yan Lin Zhou De-hong Chen hong-Bo yang Rui-Ying Miao National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous MetalsBeijing100088China Grirem Advanced Materials Co. Beijing100088China

The electrochemical formation of La-Al alloys in LiF-CaF_(2)molten salt on a molybdenum electrode at 1123 K was investigated by electrochemical techniques,such as cyclic voltammetry,square-wave voltammetry and open-circuit *** formation signals of four types of Al-La intermetallic compounds were *** Al-La alloy was obtained through galvanostatic electrolysis at 2.5 A·cm^(-2)for 3 *** phase composition and microstructure of the electrolytic products were analysed by X-ray diffraction(XRD)and scanning electron microscopy with energy-dispersive spectroscopy(EDS).XRD results show that the phase compositions of the alloys are Al_(11)La_(3)and Al,and EDS results reveal 26.7 at%La in the alloy.

关键词： Co-reduction Lanthanum aluminium alloys Molten fluorides

Coulomb Interaction in Quantum Dot with a Precessing Magnetic Field

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Communications in Theoretical Physics 2007年第5X期48卷 943-948页

作者： WU Liu-Po ZHOU shi-Ping SONG hong-yan shi Yao-Ming Department of Physics Shanghai University Shanghai 200444 China

We study electronic transport through a quantum dot （QD） with a precessing magnetic field. By using the Keldysh nonequilibrium Green function method, formulas of local density of states （LDOS） and conductance of QD are derived self-consistently. It shows that the LDOS and conductance have obvious changes with the Coulomb blockade interaction. The intensity and angle of the magnetic field or temperatures, which reflect the mesoscopic structure of the QD are derived. The superiority of this device is that the QD can be controlled easily by the magnetic field, so it is valuable to apply in generating, manipulating and probing spin state.

关键词： Coulomb interaction quantum dot precessing magnetic field

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数控刀具技术与应用探析

机械工程与自动化 2024年第2期 152-154页

作者：史红艳夏静文王燕花山西工程职业学院山西太原030009 山西北方机械制造有限责任公司山西太原030009

数控刀具是切削加工的基础工艺装备,在制造过程中与数控机床相互配合承载不同的加工工艺,共同完成材料切削加工。针对数控刀具的选用,探讨了选用要点,并以具体数控车加工为例进行了刀具的选用,以促进数控刀具更好地发展与应用。

关键词：数控刀具材料切削加工选用要点

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宁夏道地药材枸杞子等级质量标准研究

药学学报 2024年第5期59卷 1399-1407页

作者：余钟莲李薛萍杨莉王峥涛刘文静王瑞石燕红上海中医药大学中药学院上海201203 上海中医药大学中医药国际标准化研究所上海201203 上海市中医药国际标准化研究院上海201203 上海中医药大学中药研究所中药标准化教育部重点实验室上海201203 上海市浦东新区公利医院上海200135

基于传统性状鉴别结合现代中药分析手段的综合评价模式用于宁夏道地药材枸杞子等级划分关键指标的辨识和等级质量标准的建立。本草考证和市场调查指导下,将粒径大小、表皮颜色和不完善粒作为外在性状指标;聚焦枸杞子品质评价的全面性和... 详细信息

基于传统性状鉴别结合现代中药分析手段的综合评价模式用于宁夏道地药材枸杞子等级划分关键指标的辨识和等级质量标准的建立。本草考证和市场调查指导下,将粒径大小、表皮颜色和不完善粒作为外在性状指标;聚焦枸杞子品质评价的全面性和有效性,在水分、灰分、水溶性浸出物、枸杞多糖(Lyciumbarbarum polysaccharide,LBP)和甜菜碱等药典规定指标的基础上,增加枸杞酸(2-O-β-D-glucopyranosyl-L-ascorbic acid,AA-2βG)、玉米黄质双棕榈酸酯(zeaxanthin dipalmitate,ZD)和挥发性醚浸出物为内在质量指标。并通过t检验、相关性分析和主成分分析等数理统计方法,考察不同等级枸杞子外观性状与内在质量的关联,从而进行质量等级的划分和标准的制定,最后从体外细胞水平比较不同等级枸杞子提取物的活性差异。结果表明,枸杞子主要以“粒大色红”为佳;除甜菜碱外,其余指标成分均在表皮颜色鲜红和一等枸杞子中相对偏高;表皮颜色和水分、水溶性浸出物、LBP、AA-2βG和ZD含量之间存在显著相关。综合研究结果和市场流通情况,本研究以枸杞子的粒径大小和表皮颜色为基础,同时引入LBP、AA-2βG、ZD、水溶性浸出物和水分等多指标进一步指导等级划分,建立了外观性状和内在质量关键指标相结合的宁夏道地药材枸杞子等级质量标准,体外细胞活性也初步证实了一等枸杞子具有更为显著的“滋补肝肾”活性,这为枸杞子的质量控制和优质优价的实现提供了实验依据。

关键词：枸杞子道地产区外观性状内在质量等级质量标准

Formation mechanism and preparation of YAl_(2) intermetallics by electro-deoxidation with different sintering conditions

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Rare Metals 2023年第3期42卷 1067-1074页

作者： Yue-Shan Wei shi-hong yan Lin Zhou De-hong Chen Rui-Ying Miao Zhi-Qiang Wang National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous MetalsBeijing 100088China Grirem Advanced Materials Co. Beijing 100088China

A study was carried out on the preparation of YAl_(2) intermetallics from mixed oxide precursors using the method of electro-deoxidation.Y2O_(3) and Al_(2)O_(3) mixed in molar proportions of 1:2 were sintered at temperatures ranging from 800 to 12000C for different *** sintered pellet was then electrolyzed in a molten CaCl_(2) at850℃using a graphite anode at a potential of 3.1 *** this work,effects of sintering on the composition and the oxygen content in cathodic products were studied by X-ray diffraction(XRD)and oxygen-nitrogen *** mainly affects the porosity of the pellets,and it is found that porosity decreases gradually with the increase in sintering temperature and the extension of sintering *** sintered at 9000C for 4 h,the oxygen content in the cathodic product decreases to 1.85 wt%,and the efficiency of electro-deoxidation is 94.48%.At the same time,the mechanism of electrolysis was *** results suggest that the formation of YAl_(2) is a multi-step *** the reduction process from mixed oxides Y2O_(3)/Al_(2)O_(3) to YAl_(2) included many intermediate materials,such as YAlO_(3),Y3Al5O12 and YAl3,YAl_(2) intermediate alloy was prepared finally.

关键词： Yttrium aluminum oxide Molten salts YAl_(2)alloy Electro-deoxidation

Characterization and Comparison Analysis of WHO Monographs on Selected Medicinal Plants and Iso Standards of Chinese Materia Medica

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Chinese Journal of Integrative Medicine 2023年第6期29卷 540-548页

作者： yanG Jing-yi SANG Zhen WANG Rui shi yan-hong HUANG Yi-ran School of Pharmacy Shanghai University of Traditional Chinese MedicineShanghai(201203)China Institute of Traditional Chinese Medicine International Standardization Shuguang Hospital Affliated to Shanghai University of Traditional Chinese MedicineShanghai(201203)China Institute of Traditional Chinese Medicine International Standardization Shanghai University of Traditional Chinese MedicineShanghai(201203)China

Medicinal plants or Chinese materia medica(CMM)are now attracting worldwide attention as they have increasingly prominent advantages over chemical drugs in disease treatment and *** the 1990s,World Health Organization(WHO)and International Organization for Standardization established the Technical Committee of Traditional Chinese Medicine(ISO/TC 249)have carried out the development of quality standards on medicinal plants or CMMs respectively,and a considerable number of monographs and international standards have been *** the two international organizations adhere to different principles,the standards they develop naturally have different *** by market demand and international trade,ISO mainly takes quality,efficacy and safety into consideration when developing standards,while WHO pays more attention to clinical practice,quality control and medication *** to now,there is a lack of comparative analysis on the records,background,principles,basic content,and main requirements of quality standards on medicinal plants or CMMs respectively published by WHO and ***,based on international standards of CMM developed by ISO/TC 249 platform and WHO Monographs on Selected Medicinal Plants,this paper systematically compares the purposes,selected principles,standard-developing process,basic content,and main quality requirements to summarize their similarities and differences,and find their merits,aiming to serve as a reference to the development of international standards for CMMs that helps them go global.

关键词： Chinese materia medica medicinal plants international standards International Organization for Standardization Technical Committee of Traditional Chinese Medicine World Health Organization

Removal and occurrence state transformation of Ti impurity in Gd metal

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Rare Metals 2021年第8期40卷 2320-2326页

作者： Zhen-Fei yang Si-Ming Pang shi-hong yan hong-Bo yang Xiao-Wei Zhang Qiong Zhu De-hong Chen Dao-Gao Wu General Research Institute for Nonferrous Metals Beijing100088China National Engineering Reseach Center for Rare Earth Materials Grirem Advanced Materials Co.Ltd.Beijing100088China

The interaction mechanism of B and Ti in liquid Gd metal was theoretically analyzed,and the occurrence state transformation and removal of Ti impurity were experimentally analyzed in this *** research results indicated that the B additive reacted with the Ti impurity in liquid Gd metal to form the high-melting-point TiB_(2)at 1673 *** to the low density of TiB_(2)that is far lower than that of Gd,TiB_(2)floated up to the liquid surface,and then,the Ti impurity could be effectively removed from Gd *** melting time and increasing B additive amount could increase Ti removal rate,but the increase in the rate slows beyond a certain duration and B *** recommended operating parameter,melting time of 60 min and B additive content of 0.1394 wt%could reduce Ti content from 0.1534 wt%to 0.0433 wt%,and the removal rate was 71.9%.

关键词： Gd metal Ti impurity B additive TiB_(2)

Dopant-stimulated CuO Nanofibers for Electro-oxidation and Determination of Glucose

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Chemical Research in Chinese Universities 2013年第5期29卷 861-867页

作者： shi hong-yan WU Ying WANG Wen SONG Wen-bo LIU Tie-mei College of Chemistry Jilin University Changchun 130012 P. R. China China-Japan Union Hospital of Jilin University Changchun 130033 P. R. China

We described the preparation of copper oxide composite nanofibers doped with carbon nanotubes （CuO/C-NFs） or nickel oxide（CuO/NiO-NFs） by electrospinning for direct glucose determination. The interest in exploring practical CuO/C-NFs and CuO/NiO-NFs electrode materials for sensor application was fascinated by the possibility of promoting electron transfer for kinetically unfavorable glucose oxidation reactions at a lower overpo- tential and thus improving the selectivity of the electrode for glucose in electroanalysis. The morphologies of CuO/C-NFs and CuO/NiO-NFs were characterized by scanning electron microscopy（SEM） and X-ray powder diffraction（XRD）. The electrocatalytic performances of glucose were evaluated in detail by cyclic voltammetry（CV） and chronoamperometry. Facile charge transport, enhanced current response（at a lower overpotential of ＋0.35 V）, improved stability and selectivity, as well as excellent resistance towards electrode fouling were observed at CuO/ C-NFs electrode in direct glucose electroanalysis. These merits are attributed to the highly porous three-dimensional network film structure of CuO/C-NFs electrode materials and the potential synergic catalytic effect of CuO and carbon nanotubes in composite nanofibers. This study may provide a new insight into metal oxide-based composite nanofibers obtained via electrospinning for fabricating novel and high performance sensors and devices.

关键词： Copper oxide nanofiber Carbon nanotube Nickel oxide Electrospinning Glucose oxidation