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基于三维形态空间分析和仿真试验的岩体结构面剪切强度参数研究

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岩石力学与工程学报 2012年第10期31卷 2127-2138页

作者：江洎洧项伟 joachim Rohn 姚远长江科学院水利部岩土力学与工程重点实验室湖北武汉430010 中国地质大学工程学院湖北武汉430074 埃尔朗根-纽伦堡大学应用地质系德国埃尔朗根91054

获取结构面可靠的强度指标是研究岩体强度的重要基础。因不同结构面样本的巨大差异,以及剪切测试难以重复进行的实际情况,直接通过试验获取剪切参数通常难度较大且结果不理想。以具有定向变形特征的岩体剪切结构面为研究对象,探索性提... 详细信息

获取结构面可靠的强度指标是研究岩体强度的重要基础。因不同结构面样本的巨大差异,以及剪切测试难以重复进行的实际情况,直接通过试验获取剪切参数通常难度较大且结果不理想。以具有定向变形特征的岩体剪切结构面为研究对象,探索性提出采用结构面剪切测试-结构面表面形态三维空间分析-数值仿真试验相结合方法,获取真实可靠的结构面强度参数。该方法优势表现为:岩体结构面摩擦角的2个组成部分即基本摩擦角和爬坡角完全分离,且能考虑结构面形态三维特性及剪切变形方向特征;同时,力学测试和数值试验结合,克服了单纯依靠剪切测试无法重复的重大难题。

关键词：岩石力学岩体结构面剪切强度参数结构面剪切测试三维空间分析数值试验

Lithological and Structural Control of Hattian Bala Rock Avalanche Triggered by the Kashmir Earthquake 2005, Sub-Himalayas, Northern Pakistan

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Journal of Earth Science 2012年第2期23卷 213-224页

作者： Muhammad Basharat joachim Rohn Dominik Ehret Mirza Shahid Baig GeoZentrum Nordbayern Friedrich-Alexander-University Erlangen-Nuremberg Institute of Geology University of Azad Jammu and Kashmir

The Kashmir earthquake 2005 （magnitude MW 7.6） triggered thousands of mass move-ments in northern Pakistan. These mass movements were mainly rock falls, debris falls, rockslides and rock avalanches. The mass movements vary in size from a few hundred cubic meters up to about 100 million cubic meters estimated for the Hattian Bala rock avalanche, the biggest one associated with this earthquake. This mass movement, which moved in southeastern direction, created two natural dams on the valley bottom and blocked the water ways of the Karli and Tung tributaries of the Jhelum River. Topographic, lithologic and structural information were used to investigate the Hattian Bala rock ava-lanche. Geotechnical and structural maps were prepared to understand relationship between geology and structure of Hattian Bala rock avalanche. The geometry and failure mode of this rock avalanche are controlled by southeast plunging synclinal structures, lithology, a bedding parallel slip surface and a pre-existing old rockslide. The structural map shows that the mass movement failure was due to Danna and Dandbeh synclinal structures plunging southeast on the hanging wall block of the reacti-vated Muzaffarabad fault. The slip surface of the mass movement followed the bedding planes along mudstone, claystone and sandstone surfaces. The mass movement perfectly followed the pre-existing synclinal morphology of the Danna and Dandbeh synclines.

关键词： Kashmir earthquake 2005 mass movement rock avalanche Muzaffarabad fault northern Pakistan.

前驱体制备Si-B-C-N陶瓷材料析晶过程的透射电镜研究

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无机材料学报 2010年第10期25卷 1076-1080页

作者：李凌燕顾辉 Bill joachim 中国科学院上海硅酸盐研究所高性能陶瓷和超微结构国家重点实验室上海200050 Institute for Materials Science University of Stuttgart

以透射电镜的先进分析方法为主要手段,对前驱体制备Si-B-C-N陶瓷(T2-1)材料纳米尺度的微结构及其晶化过程进行了研究.结果表明,在直接经过1400℃热解后,所得到的T2-1样品出现了非均匀的SiC和Si3N4的结晶以及石墨化或BCN的团簇.为了有效... 详细信息

以透射电镜的先进分析方法为主要手段,对前驱体制备Si-B-C-N陶瓷(T2-1)材料纳米尺度的微结构及其晶化过程进行了研究.结果表明,在直接经过1400℃热解后,所得到的T2-1样品出现了非均匀的SiC和Si3N4的结晶以及石墨化或BCN的团簇.为了有效保持材料强度并抑制高温易分解Si3N4相的析出,对T2-1在1000℃热解以进行对比实验.显微结构的观察表明,经过低温热解的基体出现了均匀成分分相;即使再经过1400℃下的退火,仍能有效抑制Si3N4纳米晶的析出,从而增进了材料的高温稳定性.

关键词：前驱体陶瓷热解结晶透射电子显微学

Chlorine Analysis by Diode Laser Atomic Absorption Spectrometry

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光谱学与光谱分析 2000年第2期20卷 149-155页

作者： joachim Koch, Aleksandr Zybin and Kay Niemax Institute of Spectrochemistry and Applied Spectroscopy (ISAS), Bunsen Kirchhoff Street 11, D 44139 Dortmund, Germany Inst. Spectrochemistry Appl. S. Bunsen-Kirchhoff-Street 11 D-44139 Dortmund Germany

The general characteristics of Diode Laser Absorption Spectrometry (DLAAS) in low pressure plasmas particulary with respect to the detection of non metals are comprehensively recapitulated and discussed. Furthermore, a detector, which is based on DLAAS in a microwave induced low pressure plasma as an alternative technique for halogene specific analysis of volatile compounds and polymeric matrices is described. The analytical capability of the technique is demonstrated on the chlorine specific analysis of ablated polymer fragments as well as gas chromatographically separated hydrocarbons. Since the measurements were carried out by means of a balanced heterodyne detection scheme, different technical noise contributions, such as laser excess and RAM noise could efficiently be suppressed and the registered absorption was limited only by the principal shot noise. Thus, in the case of the polymer analysis a chlorine specific absolute detection limit of 10 pg could be achieved. Furthermore, fundamental investigations concerning the influence of hydrocarbons on the dissociation capability of the microwave induced plasma were performed. For this purpose, the carbon , chlorine and hydrogen specific stoichiometry of the compounds were empirically determined. Deviations from the exspected proportions were found to be insignificant, implying the possibility of internal standardization relative to the response of a reference sample.

关键词： Chlorine analysis Gas chromatography Laser ablation Diode laser atomic absorption spectrometry

A SQUID Bootstrap Circuit with a Large Parameter Tolerance

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Chinese Physics Letters 2013年第1期30卷 219-222页

作者： ZHANG Guo-Feng ZHANG Yi Hans-joachim Krause KONG Xiang-Yan Andreas Offenhäusser XIE Xiao-Ming State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences(CAS)Shanghai 200050 Peter Grünberg Institute(PGI-8) Forschungszentrum Jülich(FZJ)D-52425JülichGermany Joint Research Laboratory on Superconductivity and Bioelectronics Collaboration between CAS-Shanghai&FZJShanghai 200050

The voltage biased(SQUID)bootstrap circuit(SBC)was recently introduced as an effective means to reduce the preamplifier noise *** analyze the tolerances of the SBC noise suppression performance to spreads in SQUID and SBC circuit *** is found that the tolerance to spread mainly caused by the integrated circuit fabrication process could be extended by a one-time adjustable current feedback.A helium-cooled niobium SQUID with a loop inductance of 350 pH is employed to experimentally verify the *** this work,design criteria for fully integrated SBC devices with a high yield can be derived.

关键词： SQUID Bootstrap spread

Increased basolateral sorting of carcinoembryonic antigen in a polarized colon carcinoma cell line after cholesterol depletion-Implications for treatment of inflammatory bowel disease

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World Journal of Gastroenterology 2008年第10期14卷 1528-1533页

作者： Robert Ehehalt Markus Krautter Martin Zorn Richard Sparla joachim Füllekrug Hasan Kulaksiz Wolfgang Stremmel Department of Gastroenterology Hepatology and Infectious diseases University of Heidelberg INF 410 Heidelberg 69120 Germany Central Laboratory Unit University of Heidelberg INF 410 Heidelberg 69120 Germany

AIM: To investigate a possible increase of basolateral expression of carcinoembryonic antigen (CEA) by interfering with the apical transport machinery, we studied the effect of cholesterol depletion on CEA sorting and secretion. METHODS: Cholesterol depletion was performed in polarized Caco-2 cells using lovastatin and methyl-b- cyclodextrin. RESULTS: We show that CEA is predominantly expressed and secreted at the apical surface. Reduction of the cholesterol level of the cell by 40%-50% with lovastatin and methyl-b-cyclodextrin led to a significant change of the apical-to-basolateral transport ratio towards the basolateral membrane. CONCLUSION: As basolateral expression of CEA has been suggested to have anti-inflamatory properties, Cholesterol depletion of enterocytes might be a potential approach to influence the course of inflammatory bowel disease.

关键词： Inflammatory bowel disease Cholesterol Polarized secretion Carcinoembryonic antigen Caco-2

Development of an inflatable solar dryer for improved postharvest handling of paddy rice in humid climates

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International Journal of Agricultural and Biological Engineering 2017年第3期10卷 269-282页

作者： Ana Salvatierra-Rojas Marcus Nagle Martin Gummert Tom de Bruin joachim Müller Institute of Agricultural Engineering Tropics and Subtropics GroupUniversität HohenheimGarbenstrasse 9Stuttgart 70599Germany Postharvest Development Program International Rice Research Institute(IRRI)Los Baños 4031Philippines GrainPro Philippines Inc. Subic Bay 2222Philippines

Rice is the staple food for more than three billion people *** considerable progress has been made with respect to improved breeds and production practices,losses during postharvest handling remain *** and storage of paddy are two key stages where management can be *** rice,grain moisture content of 14%prevents microbiological activity,while a level of about 12%minimizes quality losses over prolonged storage *** to the need for simple and economical technologies,an inflatable solar dryer(ISD)was developed based on adaptations of the Hohenheim-type solar tunnel *** form a drying tunnel,transparent polyethylene(PE)film attaches by zipper to a reinforced black polyvinyl chloride(PVC)*** reduce heat loss,a flexible multilayer floor was used along the drying *** tunnel does not need a substructure as it is stabilized adequately from pressure created by two axial flow *** experiments,paddy was spread on the floor and mixed with a special roller *** ISD has been evaluated for paddy in the Philippines during both rainy and dry seasons and was subsequently *** drying and shade drying were carried out in parallel for comparison and product was evaluated for moisture content and quality in terms of milling recovery and head rice *** content was reduced from 23%to 14%within 26-52 h of continuous operation during the rainy season and 16%to 14%within 4-26 h of drying during the dry *** both seasons,the final moisture content of 12%was reached after prolonged drying *** was not found to be affected with respect to drying *** ISD showed advantages over sun drying,despite longer drying periods.

关键词： paddy rice postharvest handling solar dryer mobile dryer collapsible dryer Philippines

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煤系岩石物理力学参数与声波速度之间的关系

地球物理学报 2006年第5期49卷 1505-1510页

作者：孟召平张吉昌 joachim Tiedemann 中国矿业大学资源与地球科学系 Applied Geoscience Institute of Technical University Berlin Ackerstrasse 76 13355 BerlinGermany

通过超声-时间动态测试方法系统地分析了煤系沉积岩石纵波和横波速度,计算了煤系岩石动弹性力学参数,同步测试了煤系岩石的静态力学参数,建立了煤系沉积岩石动弹性力学参数与静弹性力学参数之间和煤系岩石物理力学参数与其声波速度之间... 详细信息

通过超声-时间动态测试方法系统地分析了煤系沉积岩石纵波和横波速度,计算了煤系岩石动弹性力学参数,同步测试了煤系岩石的静态力学参数,建立了煤系沉积岩石动弹性力学参数与静弹性力学参数之间和煤系岩石物理力学参数与其声波速度之间的定性定量关系.研究结果表明,煤系岩石的动弹性模量与岩石的纵波或横波速度具有很好的正相关关系,而与泊松比不具有这种正相关关系.煤系岩石的动弹性模量要大于其静弹性模量,而动泊松比要小于其静泊松比,它们之间呈线性相关关系.煤系岩石密度、单轴抗压和抗拉强度与其纵波或横波速度之间也呈正相关关系,它们分别服从二次函数、指数函数和线性函数分布.

关键词：煤系岩石声波速度物理力学参数

Distinct antifibrogenic effects of erlotinib,sunitinib and sorafenib on rat pancreatic stellate cells

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World Journal of Gastroenterology 2014年第24期20卷 7914-7925页

作者： Anne Elsner Falko Lange Brit Fitzner Martin Heuschkel Bernd joachim Krause Robert Jaster Department of Medicine Ⅱ Division of GastroenterologyUniversity Medicine Rostock18057 RostockGermany Department of Neurology University Medicine Rostock18119 RostockGermany Department of Nuclear Medicine University Medicine Rostock18057 RostockGermany

AIM: To study if three clinically available small molecule kinase inhibitors (SMI), erlotinib, sunitinib and sorafenib, exert antifibrogenic effects on pancreatic stellate cells (PSC) and analyze the basis of their ac... 详细信息

关键词： Pancreatic stellate cell Fibrosis Erlotinib Sunitinib Sorafenib