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World Journal of Gastroenterology 2009年第48期15卷 6044-6051页

作者： Michael bernhard Pitton Roman Kloeckner Sascha Herber Gerd Otto Karl friedrich Kreitner Christoph Dueber Department of Diagnostic and Interventional Radiology Johannes Gutenberg-University Department of Transplantation and Hepatobili-opancreatic Surgery University of Mainz

AIM： To compare the diagnostic capability of multidetector computed tomography （MDCT） and magnetic resonance imaging （MRI） for the detection of hepatocellular carcinoma （HCC） tumour nodules and their effect on patient management. METHODS： A total of 28 patients （25 male, 3 female, mean age 67 ± 10.8 years） with biopsy-proven HCC were investigated with 64-row MDCT （slice 3 mm native, arterial and portal-venous phase, 120 mL Iomeprol, 4 mL/s, delay by bolus trigger） and MRI （Tlfs fl2d TE/ TR 2.72/129 ms, T2tse TE/TR 102/4000 ms, 5-phase dynamic contrast-enhanced Tlfs fl3d TE/TR 1.56/4.6, Gadolinium-DTPA, slice 4 mm）. Consensus reading of both modalities was used as reference. Tumour nodules were analyzed with respect to number, size, and location. RESULTS： In total, 162 tumour nodules were detected by consensus reading. MRI detected significantly more tumour nodules （159 vs 123, P 〈 0.001） compared to MDCT, with the best sensitivity for early arterial phase MRI. False-negative CT findings included nodules ≤ 5 mm （n = 5）, ≤ 10 mm （n = 17）, ≤ 15 mm （n= 12）,≤20mm（n=4）,andlnodule〉*** missed 2 nodules ≤ 10 mm and 1 nodule ≤ 15 mm. On MRI, nodule diameters were greater than on CT （29.2 ≤25.1 mm, range 5-140 mm vs 24.1 ± 22.7 mm, range 4-129 mm, P 〈 0.005）. In 2 patients, MDCT showed only unilobar tumour spread, whereas MRI revealed additional nodules in the contralateral lobe. Detection of these nodules could have changed the therapeutic strategy. CONCLUSION： Contrast-enhanced MRI is superior to 64-row MDCT for the detection of HCC nodules. Patients should be allocated to interventional or operative treatment according to a dedicated MRI-protocol.

关键词： American Association for the Study of Liver Diseases European Association for the Study of the Liver Hepatocellular carcinoma Multidetector computed tomography Magnetic resonance imaging

基于服务的开放数字仓储架构--DNET解析

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现代图书情报技术 2010年第1期 34-40页

作者：马建霞 Paolo Manghi Wolfram Horstmann friedrich Summann 中国科学院国家科学图书馆兰州分馆兰州730000 Istituto di Scienza e Tecnologie dell'Informazione Consiglio Nazionale Delle RicercheItaly bielefeld University Library Germany

介绍DNET的基本功能和特点,明确DNET解决的核心问题:对异构仓储数据的收割聚合、对分布异构的服务调度。通过对DNET信息空间和对象模型、DNET基于服务的架构,尤其对DNET驱动层的剖析,分析DNET如何解决这两个核心问题。并对DNET的适用性... 详细信息

介绍DNET的基本功能和特点,明确DNET解决的核心问题:对异构仓储数据的收割聚合、对分布异构的服务调度。通过对DNET信息空间和对象模型、DNET基于服务的架构,尤其对DNET驱动层的剖析,分析DNET如何解决这两个核心问题。并对DNET的适用性、数字仓储联盟建设中的标准化、数字仓储联盟可提供的服务等进行探讨。

关键词： DRIVER DNET数字仓储架构基于服务的架构

Dielectrophoretic assembly of carbon nanotubes and stability analysis

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Progress in Natural Science:Materials International 2013年第4期23卷 367-373页

作者： Libao An Craig friedrich College of Mechanical Engineering Hebei Provincial Key Laboratory of Inorganic Nonmetallic MaterialsHebei United University Department of Mechanical Engineering-Engineering Mechanics Multi-Scale Technologies InstituteMichigan Technological University

Nanoscale dimensions and remarkable properties of carbon nanotubes make them promising building blocks for *** requirement is the need to manipulate single or multiple carbon nanotubes to bridge electronic *** this paper,multi-walled carbon nanotubes with a variety of sizes are assembled onto electrodes using alternative current electric felds by *** effect of the dielectrophoretic parameters and the nanotube size as well as the length uniformity on the assembly is experimentally ***–voltage characteristics of assembled carbon nanotubes are *** experimental results showed that both the dielectrophoretic parameters and length uniformity of carbon nanotubes have an infuence on the stability of assembly *** uniform carbon nanotubes with an appropriate length and suffcient stiffness,which are more controllable by dielectrophoresis,is necessary for an assembly of a small number of carbon nanotubes.

关键词： Carbon nanotube Assembly Dielectrophoresis Process parameter Stability

STRAIN-GRADIENT STRESS ANALYSIS IN SAINT-VENANT bENDING

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Acta Mechanica Sinica 1996年第3期12卷 225-242页

作者： friedrich Wilhelm Hecker Jerzy Tadeusz Pindera Technische Universitat braunschweig D-38106 Braunschweig Germany University of Waterloo Waterloo Ontario N2L 3G1 Canada

Light beam deflections caused by stress or strain gradients are inves- tigated analytically and experimentally in homogeneous beam specimens which are subjected to a particular case of flexure with shear. This study is a generalization of the prior an alytical-experimental examination of strain-gradient light deflections produced in stressed plates, which had concentrated on the simplest case where in- formation of interest is collected along a line of symmetry of the stress field. Main purpose of the present investigation is to document the efficacy of the strain-gradient method in analysis of the general case of stress state. The most interesting stress state is that in a beam subjected to the Saint-Venant bending, where the transversal and the longitudinal axes of the beam are in pure shear. The obtained results are compared with the predictions of the developed analytical models and with the pre- dictions of Filon's stress function. The procedures of evaluating the photoelastic and material coefficients using strain-gradient techniques were tested positively.

关键词： experimental stress analysis applied mechanics optical methods light propagation strain-gradient light bending testing mathematical models

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农户系统的发展障碍与潜力:认识与分析

农村经济 1997年第9期 30-32页

作者：郭正模 K.H.friedrich 四川省社会科学院

农户系统的发展障碍与潜力：认识与分析郭正模译Ｋ·Ｈ·Ｆｒｉｅｄｒｉｃｈ等农户系统发展障碍与潜力是“农业系统发展”理论和方法的关键内容。对农户及其环境最好理解为每一步都存在着发展障碍与潜力。其中对障碍的分析不仅直接与农... 详细信息

农户系统的发展障碍与潜力：认识与分析郭正模译Ｋ·Ｈ·Ｆｒｉｅｄｒｉｃｈ等农户系统发展障碍与潜力是“农业系统发展”理论和方法的关键内容。对农户及其环境最好理解为每一步都存在着发展障碍与潜力。其中对障碍的分析不仅直接与农户本身的发展目标有关，而且也与地区...

关键词：发展障碍农户障碍因素发展目标基本需求风险分析农业实践经济作物投入物资源利用

Influence of drag laws on pressure and bed material recirculation rate in a cold flow model of an 8 MW dual fluidized bed system by means of CPFD

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Particuology 2018年第1期16卷 70-81页

作者： Stephan Kraft friedrich Kirnbauer Hermann Hofbauer bioenergy 2020+ GmbH Wiener Strasse 49 A- 7540 Gussing Austria TU Wien Institute of Chemical Engineering Getreidemarkt 9/166 Vienna Austria

A cold flow model of an 8 MW dual fluidized bed （DFb） system is simulated using the commercial compu- tational particle fluid dynamics （CPFD） software package barracuda. The DFb system comprises a bubbling bed connected to a fast fluidized bed with the bed material circulating between them. As the hydrodynam- ics in hot DFb plants are complex because of high temperatures and many chemical reaction processes, cold flow models are used. Performing numerical simulations of cold flows enables a focus on the hydro- dynamics as the chemistry and heat and mass transfer processes can be put aside. The drag law has a major influence on the hydrodynamics, and therefore its influence on pressure, particle distribution, and bed material recirculation rate is calculated using barracuda and its results are compared with experimental results. The drag laws used were energy-minimization multiscale （EMMS）, Ganser, Turton-Levenspiel, and a combination of Wen-Yu]Ergun. Eleven operating points were chosen for that study and each was calculated with the aforementioned drag laws. The EMMS drag law best predicted the pressure and dis- tribution of the bed material in the different parts of the DFb system. For predicting the bed material recirculation rate, the Ganser drag law showed the best results. However, the drag laws often were not able to predict the experimentally found trends of the bed material recirculation rate. Indeed, the drag law significantly influences the hydrodynamic outcomes in a DFb system and must be chosen carefully to obtain meaningful simulation results. More research may enable recommendations as to which drag law is useful in simulations ofa DFb system with CPFD.

关键词： Cold flow modeling Fluidization Computational particle fluid dynamics(CPFD) simulation Dual fluidized bed Computational fluid dynamics

减摩耐磨用无机颗粒/高分子复合材料研究的进展

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中国塑料 2001年第8期15卷 1-5页

作者：纪秋龙章明秋容敏智 Klaus friedrich 中山大学材料科学研究所 Institute for Composite Materials

综述了减摩抗磨用无机颗粒 /高分子复合材料的最新研究进展 ,重点阐述了不同类型无机颗粒的作用机理及其对复合材料最终性能的影响 ,指出这类材料的发展趋势在于应用纳米填料 ,通过发展适当的分散技术 ,同时加强粒子与基体的结合 ,有可... 详细信息

综述了减摩抗磨用无机颗粒 /高分子复合材料的最新研究进展 ,重点阐述了不同类型无机颗粒的作用机理及其对复合材料最终性能的影响 ,指出这类材料的发展趋势在于应用纳米填料 ,通过发展适当的分散技术 ,同时加强粒子与基体的结合 ,有可能克服现有微米颗粒复合材料中存在的缺点。

关键词：无机填料摩擦磨损高分子复合材料进展减摩耐磨

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中国黄土磁颗粒分析及其古气候意义

中国科学（b辑） 1991年第6期 639-644页

作者：刘秀铭刘东生 friedrich Heller 许同春中国科学院地质研究所北京100029 瑞士联邦苏黎世高等理工大学国家地震局地球物理研究所北京100081

本文运用岩石磁学方法,对各地黄土和古土壤样品进行低温磁化率、频率磁化率和低温剩磁退磁的研究,证明了黄土中的磁颗以顺磁(单畴和多畴,即>0.03μm)为特点,而古土壤以超顺磁(<0.03μm)为主要特征.黄土中的磁铁矿相对含量(占天然剩磁强... 详细信息

本文运用岩石磁学方法,对各地黄土和古土壤样品进行低温磁化率、频率磁化率和低温剩磁退磁的研究,证明了黄土中的磁颗以顺磁(单畴和多畴,即>0.03μm)为特点,而古土壤以超顺磁(<0.03μm)为主要特征.黄土中的磁铁矿相对含量(占天然剩磁强度的百分比)比古土壤高,黄土频率磁化率的波谷、波峰分别与剖面黄土和古土壤的风化或土壤化程度相关,说明在黄土形成古土壤的成土过程中,是由于许多细小铁磁性矿物(磁赤铁矿和磁铁矿)生成,使其磁化率增高.这些细小铁磁性矿物的含量反映了古气候温湿程度的强弱和持续时间的长短.

关键词：中国黄土磁颗粒古气候磁化率

塞浦路斯阿格罗基皮亚的 CY-2a 钻孔中的硫化物矿化、热液蚀变和化学成分

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地质地球化学 1992年第6期20卷 6-15页

作者： P.M.Herzig G.H.friedrich 杨秋剑

阿格罗基皮亚(Agrokipia)硫化物矿床是一个古海底热液体系,位于特罗多斯蛇绿岩的枕状熔岩中。CY-2a钻孔深689m,打穿了上层熔岩、网状硫化物及下伏的蚀变岩石。根据蚀变矿物分布,划分出4个主要蚀变带。在绿帘石+绿泥石+钠长石+橱石+方解... 详细信息

阿格罗基皮亚(Agrokipia)硫化物矿床是一个古海底热液体系,位于特罗多斯蛇绿岩的枕状熔岩中。CY-2a钻孔深689m,打穿了上层熔岩、网状硫化物及下伏的蚀变岩石。根据蚀变矿物分布,划分出4个主要蚀变带。在绿帘石+绿泥石+钠长石+橱石+方解石矿物组合中缺失阳起石表明在钻孔底层的古温度约为300℃。金属矿物共生组合主要由黄铁矿组成,交生有闪锌矿、少量黄铜矿和量更少但分布广泛的磁黄铁矿。黄铁矿中的As含量达1.87wt%,Co/Ni比值为2.0～8.0。闪锌矿富铁,在深度小于和大于270m时其FeS平均含量分别为9.7和19.7mol%。相对于新鲜的熔岩组成来说,绿片岩相和绿磐岩化蚀变岩石贫K和Ca,富Na。矿带富含Fe,Zn,Cu、As、Si和K,其中K进入绢云母/伊利石结构中,而Ca、Na和Sr则被大量淋滤。该硫化物带ba含量呈明显异常,这主要是由于ba从斜长石中淋滤出来,并主要再沉积在绢云母/伊利石内所造成的。

关键词：硫化物矿床矿化热液化学成分