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黄河壶口至龙门段全新世古洪水滞流沉积物研究

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土壤通报 2011年第4期42卷 781-787页

作者：王夏青黄春长庞奖励查小春周芳魏海燕陕西师范大学旅游与环境学院陕西西安710062 中国科学院黄土与第四纪地质国家重点实验室陕西西安710075

通过野外考察,在黄河晋陕峡谷发现全新世古洪水滞流沉积物地层。对于采取的沉积物和黄土古土壤样品,进行磁化率、烧失量、碳酸钙和粒度成分的测试分析。综合野外观测和实验分析结果,确定它们是黄河悬移质泥沙在高水位滞流环境当中的沉... 详细信息

通过野外考察,在黄河晋陕峡谷发现全新世古洪水滞流沉积物地层。对于采取的沉积物和黄土古土壤样品,进行磁化率、烧失量、碳酸钙和粒度成分的测试分析。综合野外观测和实验分析结果,确定它们是黄河悬移质泥沙在高水位滞流环境当中的沉积物。其主要成分是粉沙,次要成分为细沙,据此确定其质地属于细沙质粉沙。其磁化率略高于黄河河床相沙质沉积物,但是远低于全新世风成黄土和古土壤。其频率曲线为极正偏态,主峰高而且尖锐,表明分析性很好,粒度成分很集中。这是因为其在黄河洪水当中长距离搬运分选的结果。与泾河、洛河和漆水河比较,黄河晋陕峡谷全新世古洪水沉积物粒度成分偏粗。这表明黄河洪水搬运动力较强,且其悬移质泥沙是流域内黄土地区和风沙地区水土流失产物的混合物。这些特大洪水沉积层之间,被坡积角砾石或者石渣土层分隔开来,每一层记录了一个古洪水事件。

关键词：黄河中游古洪水滞流沉积物悬移质全新世

SORPTION OF PHENOL AND P-NITROPHENOL ONTO A WEAKLY ANION EXCHANGER: XPS ANALYSIS AND MECHANISM

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chinese Journal of Reactive Polymers 2005年第Z1期 44-51页

作者： LI Xiaotao1,2 Pan Bingcai1 Pan Bingjun1 Zhang Weimin1 Meng Fanwei1 Chen Jinlong1 Zhang Quanxing1 1. state key laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210093, china 2. Department of {4. and Technology, state Environmental Protection Agency, Beijing 100035, china

X-ray photoelectron spectroscopy(XPS)was adopted to elucidate sorption mechanism of phenol and p-nitrophenol onto a weakly anion exchanger *** distribution of specific forms of tertiary amino group on D301 was obtained and effect of free tertiary amino group on phenol sorption onto D301 was discussed. The result indicated that the percent of the protonated tertiary amine group on polymeric matrix was much lower than the reference compound N,N-dimethylbenzylamine at an identical pH value in solution due to the much lower activity degree of hydrogen ion in inner resin phase than in the external solution. Less free amino group on D301 results in less sorption capacity of phenol and p-nitrophenol in an acidic solution. Under the experimental conditions both phenol sorption onto D301 can be explained as solid extraction and the distribution coefficient varies linearly with the content of free amino group on D301.

关键词： XPS, Anion exchanger Phenolic compounds Sorption mechanism.

Research on particle size distribution in rectangular turbulent channel flow

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Research on particle size distribution in rectangular turbul...

第九届国际水动力学会议

作者： Fu-jun Gan 1 Jian-zhong Lin 1 21 state key laboratory of Fluid Power Transmission and Control Zhejiang University 2 College of Metrology and Measurement Engineering china Jiliang University Hangzhou china

Large eddy simulations of threedimensional particle-laden turbulent channel flow are performed for Re = *** flow results are validated using the experimental data and good agreements are *** is employed to deal with PGDE,which describes PSD,involving the effect of shearinduced coagulation,which is greatly affected by the effects of turbulent transport and preferential concentration,represented by radial relative velocity and radial distribution function,*** with four different stokes number are considered to study the above effects on the evolution of *** the results,the distributions of particle number concentration,polydispersity,particle diameter are detailed discussed.

关键词： turbulent channel flow large eddy simulation Taylor-series expansion moment method relative velocity preferential concentration.

原位生成棒晶增强Ti-B-X复相陶瓷的研究

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无机材料学报 2001年第6期16卷 1243-1249页

作者：李世波温广武张宝生哈尔滨工业大学材料科学与工程学院西北工业大学凝固技术国家重点实验室西安710072

Ｂ４Ｃ与Ｔｉ在１８００°Ｃ×３５ＭＰa×１ｈ的烧结条件下反应生成了TiB2 棒晶，棒晶长度在１０～３０μｍ，其长径比在２～８范围．原位生成的棒晶赋予了材料具有极高的力学性能，材料的弯曲强度和断裂韧性分别为６８０ＭＰａ和１... 详细信息

Ｂ４Ｃ与Ｔｉ在１８００°Ｃ×３５ＭＰa×１ｈ的烧结条件下反应生成了TiB2 棒晶，棒晶长度在１０～３０μｍ，其长径比在２～８范围．原位生成的棒晶赋予了材料具有极高的力学性能，材料的弯曲强度和断裂韧性分别为６８０ＭＰａ和１２ＭＰａ·ｍ１／２．通过Ｘ射线衍射检测了材料的物相组成，利用扫描电镜及透射电镜观察了材料的显微结构．最后讨论了温度及金属Ｔｉ含量对棒晶ＴiＢ2的生成及发育的影响．

关键词：原位生成 TiB2棒晶显微结构棒晶发育硼化钛棒晶钛-硼-碳复相陶瓷

Effects of Surface-Active Elements Sulfur on Flow Patterns of Welding Pool

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Journal of Materials science & Technology 2005年第3期21卷 408-414页

作者： Yuzhen ZHAO, Yongping LEI and Yaowu SHI School of Materials science and Engineering, Beijing University of Technology, Beijing 100022, china School of Materials science and Engineering Beijing University of Technology Beijing 100022 China

A 3D mathematical model is developed to calculate the temperature and velocity distributions in a moving gas tungsten arc (GTA) welding pool with different sulfur concentrations. It has been shown that, the weld penetration increases sharply with increasing sulfur content. When sulfur content increases beyond 80 × 10-6, the increase in sulfur content does not have an appreciable difference on the welding pool size and shape, and the depth/width remains constant. Sulfur changes the temperature dependence of surface tension coefficient from a negative value to a positive value and causes significant changes on flow patterns. The increase in soluble sulfur content and the decrease at free surface temperature can extend the region of positive surface tension coefficient. As sulfur content exceeds 125×10-6, the sign of surface tension coefficient is positive. Depending upon the sulfur concentrations, three, one or two vortexes that have different positions, strength and directions may be found in the welding pool. The contrary vortexes can efficiently transfer the thermal energy from the arc, creating a deep welding pool. An optimum range of sulfur content is 20-150×10-6.

关键词： Surface-active elements Sulfur Plow patterns Depth/width

The Suppressors of RNA Silencing Encoded by Lily mottle virus

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The Suppressors of RNA Silencing Encoded by Lily mottle viru...

中国植物病理学会2008年学术年会

作者： Bao-hua Kong~1 Jialin yu~(2*) Hai-ru Chen1* Dawei Li~2 Chenggui Hang~2 Xiangbing Wang~2 Andy O. Jackson~3 Hong Cai~1 1.The key laboratory for Plant Pathology of Yunnan Province, Yunnan Agricultural University, Kunming,Yunnan, P.R. china 2. state key laboratory of Agro-Biotechnology, china Agricultural University,Beifing, P.R. china 3.The University of California-Berkeley, the United states

Lily mottle virus (LMoV) is the type species of the genus Potyvirus and its single-stranded, plus-sense In this study, it was investigated and studied whether these proteins might have RNA silencing-suppression activities by agro- infiltration with recombinant vectors of Potato virus X. The phenotype observation of green fluorescent protein (gfp) expression and Northern Blot showed that the gene silencing of gfp transgenic Nicotiana benthamiana 16C induced by homologous sequence was strongly suppressed by the immixture infiltration of HC pro, but weekly suppressed by the immixture infiltration of 6k2. In the plants infiltration, the gfp mRNA accumulation of HC pro was very higher than that in the non-suppressed controls, but 6k2 was little higher than that in the non-suppressed controls. The siRNA accumulation of HC pro was very lower than that in the non-suppressed controls, but 6k2 was little lower than that in the non-suppressed controls. These results suggested that HC pro and 6k2 genes of LMoV were potentially encoded for proteins as RNA silencing suppressors and the suppressing ability of 6k2 is much weaker than HC pro. The local and system suppression ability of LMoV HC pro were compared with the two representative HC pro of SCMV and TEV belonging to Potyvirus and infecting respectively monocotyledon and dicotyledon by agro- in-filtration with recombinant vectors of pBin219 on Nicotiana benthamiana WT and Nicotiana benthamiana 16C, Northern Blot and Western Blot assays. The agro- infiltration experiments result showed that the LMoV HC pro and SCMV HC pro had the similar local and system suppressing activity on Nicotiana benthamiana WT and 16C respectively. TEV HC pro showed the strongest local suppression ability and the weakest system suppression ability among the HC pro of the three viruses on Nicotiana benthamiana WT and *** gfp mRNA accumulation and gfp protein accumulation were consistent with the phenotype. It indicated that LMoV HC pro maybe showed

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RhoA relative GAPs modulate dendritic morphogenesis of rat cortical neurons

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RhoA relative GAPs modulate dendritic morphogenesis of rat c...

中国神经科学学会第九届全国学术会议暨第五次会员代表大会

作者： Xin-Ru ZHU,Lan MA~* Pharmacology Research Center and the state key laboratory of Medical Neurobiology,Shanghai Medical College and Institutes of Brain science,Fudan University,Shanghai 200032,{4.

＜正＞The development of dendrites involves several discrete morphological steps,which depends on the regulation of the *** RhoGTPases,including RhoA,Rac1 and Cdc4.,function as critical regulators of the actin cytoskeleton to play important roles in dendritic and spine morphology ***-activation of RhoA/Rock signaling causes a defect in dendritic outgrowth and branching,while down-regulation of RhoA/Rock signaling shows a more complex dendritic tree compared with ***,regulation of RhoA activity,especially down regulation of it,is critical for dendritic morphology during neuronal *** the present study,we have screened expression of 19 RhoA relative GTPase-activating proteins（RhoAGAPs）,negative regulators of RhoA,in the cortical *** are MPRIP,QLC1,DLC2,DLC3,P1190A,P190B,GRAF,GRAF2,Myosin9a,Myosin9b, RICS,ARAP1,ARAP2,P115 RhoGAP,srGAP1,GMIP,PARG1 and P50 *** loss-of-function analysis, we identify two of them,which highly expressed in neurons,regulate dendritic morphology *** of either of them decreases dendritic length and number both in cultured rat cortical neurons in vitro and developing cortical neurons in *** of RhoA/ROCK signaling restores the defects of dendritic morphology induced by knockdown of ***,these data suggest that some but not all of RhoAGAPs could modulate dendritic morphogenesis of rat cortical neurons via repression of RhoA/Rock signaling,providing novel insight into the physiological functions of RhoAGAPs in the dendritic development.

关键词： RhoA GTPase-activating proteins(GAPs) dendritic development

Micro-mechanical analysis of dynamic processes of nanomanipulation

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science china(Physics,Mechanics & Astronomy) 2004年第z1期47卷 88-92页

作者： HU Jie, ZHANG Yujun, LI Peng, WANG Hui, HUANG Lan & HU Yuanzhongstate key laboratory of Tribology, Tsinghua University, Beijing 100084. china Department of Physics, Tsinghua University, Beijing 100084. china College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, china 1. state key laboratory of Tribology Tsinghua University 100084 Beijing China 2. Department of Physics Tsinghua University 100084 Beijing China 3. College of Chemistry and Molecular Engineering Peking University 100871 Beijing China

In this study, atomic force microscope (AFM) tips are used as tools to cut and manipulate carbon nanotubes on various surfaces. The lateral forces acting on AFM tips during manipulation are also recorded and analyzed from the perspective of micro-mechanics. It is found that differences in surface conditions can lead to obvious increase in micro-friction between nanotube and substrate. And also due to rehybridization, carbon nanotubes present excellent resilience when undergoing different degrees of strain. Finally, carbon nanotubes can complexly deform from elastic stage to plastic stage before complete rupture.

关键词： nanomanipulation, carbon nanotubes, AFM tips, micro-mechanics.

Performance Analysis for Multimedia Communication Systems with a Multilayer Queuing Network Model

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china Communications 2018年第8期15卷 67-76页

作者： Xuehua Tang Zhongyuan Wang Xiaojun Li Zhen Han Zheng He Youming Fu School of remote sensing and Information Engineering Wuhan UniversityWuhan 430079China Research Institute of Wuhan University in Shenzhen Shenzhen 518000China School of Computer science Wuhan UniversityWuhan 430072China state Grid Economic and Technological Research Institute CO. LTDBeijing 102209China

Software performance evaluation in multimedia communication systems is typically formulated into a multi-layered client-server queuing network(MLCSQN) problem. However, the existing analytical methods to MLCSQN model cannot provide satisfactory solution in terms of accuracy, convergence and consideration of interlocking effects. To this end, this paper proposes a heuristic solving method for MLCSQN model to boost the performance prediction of distributed multimedia software systems. The core concept of this method is referred to as the basic model, which can be further decomposed into two sub-models: client sub-model and server sub-model. The client sub-model calculates think time for server sub-model, and the server sub-model calculates waiting time for client sub-model. Using a breadthfirst traversal from leaf nodes to the root node and vice versa, the basic model is then adapted to MLCSQN, with net sub-models iteratively resolved. Similarly, the interlocking problem is effectively addressed with the help of the basic model. This analytical solver enjoys advantages of fast convergence, independence on specific average value analysis(MVA) methods and eliminating interlocking *** experimental results on accuracy and computation efficiency verify its superiority over anchors.

关键词： multimedia communication system queuing network performance evaluation