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国外非金属矿与宝石 1989年第4期 42-43页

作者： h.bank E.Gudelin 咸阳非金属矿研究所

本文介绍了一颗金绿宝石成因分析的始末。这颗宝石开始被认为是合成的,根据各种矿物学和宝石学鉴定数据,最后证明是天然成因的。（共2页)

关键词：金绿宝石成因

矿物中的变石效应:金绿宝石,石榴石,刚玉,荧石

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世界地质 1985年第Z1期 140-150页

作者： K.Schmetzer h.bank E.Gübelin 高国平

变石状（alexandrite-like）矿物的吸收光谱和它们的颜色起因作了概述。变石,是金绿宝石矿物的一个变种,它的颜色被认为是Cr3+出现在金绿宝石结构中的Al3+位置造成的,它进入Al2位置比进入Al1位置更为优先,因为它的Al—O间距较大。变石... 详细信息

变石状（alexandrite-like）矿物的吸收光谱和它们的颜色起因作了概述。变石,是金绿宝石矿物的一个变种,它的颜色被认为是Cr3+出现在金绿宝石结构中的Al3+位置造成的,它进入Al2位置比进入Al1位置更为优先,因为它的Al—O间距较大。变石的吸收光谱显示出处于八面体配位的晶格位置中Fe3+和Cr3+的强带。Cr3+光谱中较强组份的数量和偏振强度可用Al2配位多面体（m对称）的畸变加以解释。在Al1位置上的Cr3+的谱带强度较低,并且只能看成Cr3+（Al2）带的台肩。变石状石榴石可被细分为富铬镁铝榴石和富锰铝榴石质的、含钒和（或）铬的镁铝榴石。在两个变石状石榴石族中,Cr3+（4T2←4A2）和V3+（3T2←3T1）的最大吸收大致位于17500Cm-1的光谱区。这一事实可用两个石榴石族县有近似的晶体场强度解释之。变石状天然刚玉的光谱则用Cr3+(V3+)、Fe3+的d-d跃迁以及Fe2+/Ti4+和Fe2+/Fe3+的电荷转移带的迭加来解释。在变石状萤石谱中,可以观察到y3+、Ce3+和Sm2+的吸收带。所有具有颜色变化的矿物和其它变石状相的吸收谱,除了在17300和17800cm-1之间有一个最大的强吸收之外度还在1500和1600cm-1之间以及19700和2IOOOcm-1之间出现最小吸收。比色研究表明,将日光变为人造光时,色,图中主要波长向其红光区位移。在日光中是绿色的晶体,在人造光中通常变成红色,在日光中是蓝绿色或浅蓝色的晶体,在人造光中变成淡红紫色。

关键词：石榴石变石吸收光谱石榴子石宝石亚历山大石非金属矿物刚玉最大吸收铍尖晶石铍矿物金绿宝石矿物

Prediction of vertical displacement for a buried pipeline subjected to normal fault using a hybrid FEM-ANN approach

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 428-443页

作者： hedye JALALI Reza YEGANEh KhAKSAR Danial MOhAMMADZADEh S. Nader KARBALLAEEZADEh Amir h.GANDOMI Department of Civil Engineering Architecture and UrbanismSadjad University of TechnologyPO Box ***MashhadIran Department of Civil Engineering Faculty of EngineeringEqbal Lahoori Institute of Higher EducationPO Box ***MashhadIran Faculty of Civil Engineering Architectureand ArtScience and Research Branch of Islamic Azad UniversityPO Box ***TehranIran Faculty of Engineering&Information Technology University of Technology SydneyUltimoNSW 2007Australia University Research and Innovation Center(EKIK) Óbuda UniversityBudapest 1034Hungary

Fault movement during earthquakes is a geotechnical phenomenon threatening buried pipelines and with the potential to cause severe damage to critical ***,effective prediction of pipe displacement is crucial for preventive management *** study aims to develop a fast,hybrid model for predicting vertical displacement of pipe networks when they experience *** this study,the complex behavior of soil and a buried pipeline system subjected to a normal fault is analyzed by using an artificial neural network(ANN)to generate predictions the behavior of the soil when different parameters of it are *** this purpose,a finite element model is developed for a pipeline subjected to normal fault *** data bank used for training the ANN includes all the critical soil parameters(cohesion,internal friction angle,Young’s modulus,and faulting).Furthermore,a mathematical formula is presented,based on biases and weights of the ANN *** results show that the maximum error of the presented formula is 2.03%,which makes the proposed technique efficiently predict the vertical displacement of buried pipelines and hence,helps to optimize the upcoming pipeline projects.

关键词： buried pipelines normal Fault finite element method multilayer perceptron neural network formulation

hybrid robust fault detection and isolation of satellite reaction wheel actuators

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Journal of Control and Decision 2024年第1期11卷 117-131页

作者： h.Abbasi Nozari S.J.Sadati Rostami Paolo Castaldi Silvio Simani Faculty of Electrical and Computer Engineering Babol Noshirvani University of TechnologyBabolIran Department of Electrical Electronic and Information EngineeringUniversity of BolognaCesenaItaly Department of Engineering University of FerraraFerraraItaly

In this paper,a combined robust fault detection and isolation scheme is studied for satellite system subject to actuator faults,external disturbances,and parametric *** proposed methodology incorporates a residual generation module,including a bank of filters,into an intelligent residual evaluation ***,residual filters are designed based on an improved nonlinear differential algebraic approach so that they are not affected by external *** residual evaluation module is developed based on the suggested series and parallel ***,a new ensemble classification scheme defined as blended learning integrates heterogeneous classifiers to enhance the performance.A wide range of simulations is carried out in a high-fidelity satellite simulator subject to the constant and time-varying actuator faults in the presence of disturbances,manoeuvres,uncertainties,and *** obtained results demonstrate the effectiveness of the proposed robust fault detection and isolation method compared to the traditional nonlinear differential algebraic approach.

关键词： Robust fault detection and isolation reaction wheels blended learning series and parallel fault detection and isolation forms satellite attitude control system

Summer Warming Limited Bud Output Drives a Decline in Daughter Shoot Biomass through Reduced Photosynthetis of Parent Shoots in Leymus chinensis Seedlings

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1667-1675页

作者： Song Gao Ruocheng Xu Lin Li Jiao Wang Nian Liu Johannes M.h.Knops Junfeng Wang Graduate School Changchun UniversityChangchun130022China Key Laboratory of Vegetation Ecology Ministry of EducationInstitute of Grassland ScienceSchool of Life SciencesJilin Songnen Grassland Ecosystem National Observation and Research StationNortheast Normal UniversityChangchun130024China Jilin Agricultural Radio and Television School Changchun130599China Department of health and Environmental Sciences Xi’an Jiaotong Liverpool UniversitySuzhou215000China

Understanding how summer warming inﬂuences the parent and daughter shoot production in a perennial clonal grass is vital for comprehending the response of grassland productivity to global ***,we conducted a simulated experiment using potted Leymus chinensis,to study the relationship between the photosynthetic activ-ity of parent shoots and the production of daughter shoots under a whole(90 days)summer warming scenario(+3°C).The results showed that the biomass of parents and buds decreased by 25.52%and 33.45%,respectively,under warming *** reduction in parent shoot biomass due to warming directly resulted from decreased leaf area(18.03%),chlorophyll a(18.27%),chlorophyll b(29.21%)content,as well as a reduction in net photosynthetic rate(7.32%)and the maximum quantum efﬁciency of photosystem II(PSII)photochemistry(4.29%).The decline in daughter shoot biomass was linked to a decrease in daughter shoot number(33.33%)by ***,the number of belowground buds increased by 46.43%.The results indicated that long-term summer warming reduces biomass accumulation in parent shoot by increasing both limitation of stoma and ***,the parent shoot allocates relatively more biomass to the belowground organs to maintain the survival and growth of ***,buds,as a potential aboveground population,could remedy for the cur-rent loss of parent shoot density by increasing the number of future daughter shoots if summer warming subsides.

关键词： Warming parent shoot bud bank photosynthesis chlorophyllﬂuorescence Leymus chinensis

Long term omeprazole therapy for reflux esophagitis:follow-up in serum gastrin levels,EC cell hyperplasia and neoplasia

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World Journal of Gastroenterology 2000年第6期6卷 789-792页

作者： Pankaj Singh Anant Indaram Ronald Greenberg Vernu Visvalingam Simmy bank Division of Gastroenterology Albert Einstein Colege of MedicineLong Island Jewish Medical CenterNew Hyde ParkNew York

AIM To evaluate the long-term safety ofomeprazole in patients of gastroesophagealreflux disease resistant to treatment with h2receptor *** We prospectively followed 33patients on omeprazole therapy for severeerosive esophagitis for 5-8 years,with periodicgastrin levels,*** infection,gastricbiopsies for incidence of ECL cell hyperplasia,carcinoids,gastric atrophy and *** 185 patient follow-up years and 137 gastricbiopsies were *** Among the 33 patients,36% reachedtheir peak gastrin levels in an average of 8months to one year,then drifted Down slowlyover 1-2 year period to just above their baselinelevel,24% of the patients had a peak gastrinlevel above 400ng·L^1 and one patient had apeak level above 1000 ng·L^*** patient had amild ECL cell hyperplasia which was self limitingand did not show any dysplastic *** percent of patients were positive *** *** gastric biopsies did notshow gastric atrophy,intestinal metaplasia orneoplastic *** In a series of 33 patients followed for 5 - 8 years on omeprazole therapy for severe reflux esophagitis, we did not observe any evidence of significant ECL cell hyperplasia, gastric atrophy, intestinal metaplasia, dysplasia or neoplastic changes.

关键词： gastroesophageal reflux proton pump inhibitors enterochromaffin cell hypergastrinemia carcinoid tumor biopsy

Effect of a novel dietary supplement on ph levels of healthy volunteers:a pilot study

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Journal of Integrative Medicine 2013年第6期11卷 384-388页

作者： Stephen Douglas Anton Xiaomin Lu Ginny bank Kacey heekin Debbie Saha Pamela J.Dubyak heather Ann hausenblas Department of Aging and Geriatric Research University of Florida Department of Clinical and health Psychology University of Florida Department of Biostatistics University of Florida RFI Ingredients Department of Sport and Exercise Sciences University of Florida Department of Sport and Exercise Sciences Jacksonville University

OBJECTIVE： To examine the effects of a greens alkalizing dietary supplement on urinary ph levels in individuals with lower-than-average ph levels. METhODS： The present study investigated the effects of an alkalizing formula （Reserveage Wholeganic GreensTM） on four individuals who had average urinary ph levels below 6.0 for three consecutive days. Following the three-day, baseline period, participants received Reserveage Wholeganic GreensTM for four consecutive days and were instructed to continue to measure their urine ph levels. Paired samples t-tests were used to examine ph levels before and after a four-day treatment period with Reserveage Wholeganic GreensTM. RESULTS： Compared to baseline, mean urine ph levels in all volunteers were significantly higher following the supplementation with Reserveage Wholeganic GreensTM （5.89 ±0.20 vs 5.56 ± 0.23; P〈0.01）. Participants＇ ph levels were also significantly higher than baseline on days 5, 6, and 7 of the treatment period （P 〈 0.05）. Noteworthy, on day 7, participants＇ mean ph levels were significantly higher than at the beginning of the treatment period （6.03 ± 0.15 at day 7 vs 5.65 ± 0.24 at day 4; P 〈 0.01）. CONCLUSION： The findings of this study suggest that supplementation with Reserveage Wholeganic GreensTM has an alkalizing effect on the body and can increase the urine ph levels in individuals with lower-than-average ph levels.

关键词： dietary supplements urinalysis acidosis pilot study

重塑世界经济地理(2009年世界发展报告概述)

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城市与区域规划研究 2009年第3期2卷 135-168页

作者： The International bank for Reconstruction and Development/ The World bank,1818 h Street, NW,Washington,D.G.20433,USA. 国际复兴开发银行世界银行

世界银行的年度出版物——《世界发展报告》,自1978年起开始发表,今年是第31期。《2009年世界发展报告:重塑世界经济地理》由世界银行发展经济局和可持续发展网络共同发起,报告由英德米特·吉尔(Indermit Gill)领导的工作组执笔编写,布... 详细信息

世界银行的年度出版物——《世界发展报告》,自1978年起开始发表,今年是第31期。《2009年世界发展报告:重塑世界经济地理》由世界银行发展经济局和可持续发展网络共同发起,报告由英德米特·吉尔(Indermit Gill)领导的工作组执笔编写,布鲁斯·罗思-拉森(Bruce Ross-Larson)担任主编。罗伯特·佐立克(Robert Zoellick)行长为报告作序。该报告的英文版于2008年11月由世界银行出版,中文版由清华大学出版社于2009年2月正式出版。本文由清华大学建筑学院毛其智教授摘编自该报告中文文件中"概述"一节。

关键词：世界经济地理落后地区经济一体化干预措施发展中国家经济发展发达地区发展报告基础设施经济增长

Design, simulation and construction of the Taban tokamak

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Plasma Science and Technology 2018年第4期20卷 112-120页

作者： h R MIRZAEI R AMROLLAhI Statistics of Department of Energy Engineering & Physics Amirkabir University of Tehran Tehran lran

This paper describes the design and construction of the Taban tokamak, which is located in Amirkabir University of Technology, Tehran, Iran. The Taban tokamak was designed for plasma investigation. The design, simulation and construction of essential parts of the Taban tokamak such as the toroidal field(TF) system, ohmic heating(Oh) system and equilibrium field system and their power supplies are presented. For the Taban tokamak, the toroidal magnetic coil was designed to produce a maximum field of 0.7 T at R?=?0.45 m. The power supply of the TF was a130 kJ, 0–10 kV capacitor bank. Ripples of toroidal magnetic field at the plasma edge and plasma center are 0.2% and 0.014%, respectively. For the Oh system with 3 kA current, the stray field in the plasma region is less than 40 G over 80% of the plasma volume. The power supply of the Oh system consists of two stages, as follows. The fast bank stage is a 120 μF, 0–5 k V capacitor that produces 2.5 kA in 400 μs and the slow bank stage is 93 mF, 600 V that can produce a maximum of 3 kA. The equilibrium system can produce uniform magnetic field at plasma volume. This system’s power supply, like the Oh system, consists of two stages, so that the fast bank stage is 500 μF, 800 V and the slow bank stage is 110 mF, 200 V.

关键词： tokamak magnetic field equilibrium

Microstructure and creep properties of Mg-4Al-2Sn-1(Ca,Sr) alloys

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Transactions of Nonferrous Metals Society of China 2010年第7期20卷 1184-1191页

作者： B.h.KIM K.C.PARK Y.h.PARK I.M.PARK Department of Material Science and Engineering Pusan National UniversitySan 30 Jangjeon-dongGeumjeong-guBusan 609-735Korea

The effects of Ca and Sr addition on the microstructure and creep properties of Mg-4Al-2Sn alloys were examined. Tensile tests at 25 ℃ and 200 ℃ and creep tests at 150 ℃ and 200 ℃ were carried out to estimate the room temperature and high temperature mechanical properties of these alloys. The microstrueture of the Mg-4Al-2Sn alloy showed dendritic a-Mg, Mg17Al12 and Mg2Sn phases. The latter two phases precipitated along the grain boundaries. The addition of Ca and Sr resulted in the formation of ternary CaMgSn and SrMgSn phases within the grain. The grain size was reduced slightly with the addition of Sr and Ca. The tensile strength was decreased by the addition of Ca and Sr at room temperature. however, the high temperature tensile strength was increased. The creep strength was improved by the addition of Ca and Sr.

关键词： magnesium alloys Ca Sr void initiation mechanical properties creep mechanism