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黄土地层大规模地震液化滑移的机理与风险评估

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岩土工程学报 2020年第1期42卷 1-19页

作者：王兰民中国地震局(甘肃省)黄土地震工程重点实验室中国地震局兰州地震研究所

2018年印度尼西亚帕卢7.4级地震造成的低角度饱和土层大规模滑移灾难对黄土地区地震造成的土层大规模低角度滑动灾害研究具有重要的警示意义。为了研究黄土地层大规模地震液化滑移机理,通过对国内外强震触发的典型黄土地震液化灾害进行... 详细信息

2018年印度尼西亚帕卢7.4级地震造成的低角度饱和土层大规模滑移灾难对黄土地区地震造成的土层大规模低角度滑动灾害研究具有重要的警示意义。为了研究黄土地层大规模地震液化滑移机理,通过对国内外强震触发的典型黄土地震液化灾害进行深入的调查分析,基于现场大型探槽和钻孔勘探、室内动三轴试验、现场剪切波速测试、SPT测试、土体微结构测试和数值模拟分析,揭示了饱和黄土液化的特征和机理,提出了饱和黄土场地液化的初判与详判方法,研究了黄土大规模地层液化滑移的滑动条件、运动学及动力学特征,论述了黄土地层大规模地震液化滑移的机制,构建了滑距和致灾范围预测模型;提出了液化滑移灾害的概率风险评估方法,给出了不同超越概率下黄土地层大规模地震液化灾害风险区划图;并从主动防控、被动防控和综合监测预警3个方面提出了黄土地层大规模液化滑移灾害的防控途径及措施。研究结果可为黄土地层大规模液化滑移灾害风险评估与防治提供理论依据。

关键词：黄土地层液化判别滑移机理滑距和致灾范围风险评估

Correlation between metastatic lymph node ratio and prognosis in patients with extrahepatic cholangiocarcinoma

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World Journal of Gastroenterology 2015年第14期21卷 4255-4260页

作者： Jian-Wei Zhang Yun-Mian Chu Zhong-min lan Xiao-Long Tang Ying-Tai Chen Cheng-Feng Wang Xu Che Department of Abdominal Surgery Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical College

AIM: To investigate the prognostic value of metastaticlymph node ratio(MLNR) in extrahepatic cholangiocarcinoma(ECC) patients undergoing radical ***: Seventy-eight patients with ECC were *** between various clinicopathologic factors and prognosis were investigated by KaplanMeier *** Cox proportional-hazards model was used for multivariate survival ***: The overall three- and five-year survival rates were 47.26% and 23.99%, *** of 0, 0-0.2, 0.2-0.5, and > 0.5 corresponded to fiveyear survival rates of 28.59%, 21.60%, 18.84%, and 10.03%, *** analysis showed that degree of tumor differentiation, lymph node metastasis, MLNR, tumor-node-metastasis(TNM) stage, and margin status were closely associated with postoperative survival in ECC patients(P 0.5, 0.2-0.5, 0-0.2, and 0 was 15 mo, 24 mo, 23 mo, and 35.5 mo, *** were statistical differences in survival time between patients with different MLNR(χ2 = 15.38; P < 0.01).CONCLUSION: MLNR is an independent prognostic factor for ECC patients after radical resection and is useful for predicting postoperative survival.

关键词： Cholangiocarcinoma Metastatic lymph node Prognosis

Synthesis and Characterization of Sulfonated Polyphosphazene-graft-Polystyrene Copolymers for Proton Exchange Membranes

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Chinese Journal of Polymer Science 2014年第2期32卷 151-162页

作者： min-lan He Hu-lin Xu Yan Dong Jia-hong Xiao Peng Liu Feng-yan Fu Saghir Hussain Shu-zhen Zhang Chao-jun Jing Qun Yu 朱长进 Department of Applied Chemistry Beijing Institute of Technology Beijing Qintian Science & Technology Development Co. Ltd Beijing Institute of Transfusion Medicine

A novel series of polyphosphazene-grafl-polystyrene （PP-g-PS） copolymers were successfully prepared by atom transfer radical polymerization （ATRP） of styrene monomers and brominated poly（bis（4-methylphenoxy）phosphazene） macroinitiator. The graft density and the graft length could be regulated by changing the bromination degree of the macroinitiator and the ATRP reaction time, respectively. The PP-g-PS copolymers readily underwent a regioselective sulfonation reaction, which occurred preferentially at the polystyrene sites, producing the sulfonated PP-g-PS copolymers with a range of ion exchange capacities. The resulting sulfonated PP-g-PS membranes prepared by solution casting showed high water uptake, low water swelling and considerable proton conductivity. They also exhibited good oxidative stability and high resistance to methanol crossover. Morphological studies of the membranes by transmission electron microscopy showed clear nanophase-separated structures resulted from hydrophobic polyphosphazene backbone and hydrophilic polystyrene sulfonic acid segments, indicating the formation of proton transferring tunnels. Therefore, these sulfonated copolymers may be candidate materials for proton exchange membranes in direct methanol fuel cell （DMFC） applications.

关键词： Atom transfer radical polymerization Direct methanol fuel cell Graft copolymers Proton exchange membrane Polyphosphazenes.

Studies on the Reaction of Substituted 6-Nitrocoumarin with Anilines

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Chinese Chemical Letters 1999年第10期10卷 811-812页

作者： Long Fei XIE Shi Ping XU Song XU lan min LI(Institute of Materia Medica, Chinese Academy of Medical Sciencesand Peking Union Medical College, Beijing 100050) Chinese Acad Med Sci Inst Mat Med Beijing 100050 Peoples R China Peking Union Med Coll Beijing 100050 Peoples R China

3-Acetyl-7-hydroxy-8-methyl-6-nitrocoumarin reacted with substituted anilines, and fission of the heterocyclic ring occurred.

关键词： 6-nitrocoumarin heterocyclic ring fission Schiff base hydrazone

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项目管理协作模式的知识发现模型

科技进步与对策 2008年第10期25卷 162-165页

作者：蓝敏浙江工商大学浙江杭州310018

在建立和分析岗位Agent工作机制的基础上,以自组织特征神经网络SOM为依托,建立了项目管理协作模式的知识发现模型。目的是通过对项目信息的及时与智能化采集,建立健全项目信息的管理机制,并在此基础上建立与项目进程同步的知识发现模型... 详细信息

在建立和分析岗位Agent工作机制的基础上,以自组织特征神经网络SOM为依托,建立了项目管理协作模式的知识发现模型。目的是通过对项目信息的及时与智能化采集,建立健全项目信息的管理机制,并在此基础上建立与项目进程同步的知识发现模型:项目管理协作模式的发现模型。协作是任何项目管理活动中不可或缺的要素。项目管理活动中有谁参与、如何参与、参与程度和效果如何等对于项目管理的成败都有举足轻重的作用。协作的实质是岗位间的协作,脱离岗位谈项目管理协作模式是没有意义的。

关键词：项目管理岗位Agent SOM 协作模式知识发现

Effects of a carbohydrate-electrolyte beverage on blood viscosity after dehydration in healthy adults

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Chinese Medical Journal 2010年第22期123卷 3220-3225页

作者： CHANG Cui-qing CHEN Yan-bo CHEN Zhi-min ZHANG lan-tao Institute of Sports Medicine Peking University Third HospitalBeijing 100191 China

Background The consumption of carbohydrate-electrolyte beverages （CEs） has been known to be more effective than plain water for recovery from dehydration. This phenomenon suggests that the ingestion of CEs after dehydration is better than water for maintaining body fluid and plasma volume, and for the recovery from hemoconcentration and high blood viscosity as well. High blood viscosity causes infarction and other cardiovascular events. In this study, CE was compared with water and tea for the ability to reduce increased blood viscosity after dehydration. Methods A crossover random control study was conducted to assess the effectiveness of three beverages for rehydration and decreasing of blood viscosity. Following exercise-induced dehydration of 2.2% of body weight in a permanent warm environment, 10 male subjects rested in a thermoneutral environment for 3 hours （rehydration period, REP）. The subjects ingested test beverages equal to their body weight loss during the first 20 minutes in REP. Blood and urine samples were obtained throughout the experiments to assess the rehydration effect. Results The change in blood viscosity at a shear rate of 5/s was significantly lower in CE （（-1.66±0.21） mPa.s） in comparison to water （（-0.95±0.26） mPa.s） or tea （（-0.92±0.14） mPa.s） at 60th minute during the REP. The fluid retention rate was significantly greater for CE （（77.0±3.9）%） than water （（61.2±3.4）%） and tea （（60.5±3.7）%） for 3 hours of rest in REP. Conclusions The recovery from high blood viscosity induced by dehydration was higher with CE consumption than with water or tea. These results suggest that CE is useful for normalizing increased blood viscosity due to exercise-induced dehydration.

关键词： carbohydrate-electrolyte beverages blood viscosity hemoconcentration plasma volume fluid retention

用Lebesgue测度积分理论分析项目外部社会效益的新思路

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科技进步与对策 2010年第19期27卷 85-88页

作者：蓝敏浙江工商大学工商管理学院浙江杭州310018

根据Lebesgue测度积分理论与方法,将项目视作由项目的外部社会效益组成的集合,通过构造可测度的项目外部社会效益集合分析项目的外部社会效益;或者在定义的可测度的项目集合上寻找可积函数,使可积函数在项目集合的测度上的积分成为项目... 详细信息

根据Lebesgue测度积分理论与方法,将项目视作由项目的外部社会效益组成的集合,通过构造可测度的项目外部社会效益集合分析项目的外部社会效益;或者在定义的可测度的项目集合上寻找可积函数,使可积函数在项目集合的测度上的积分成为项目的外部社会效益或者能够反映项目外部社会效益的指标,从而为项目的外部社会效益分析寻求新的思路。

关键词： Lebesgue 测度积分项目社会效益辐射效应

基于GIS的秦巴山区土壤侵蚀空间特征分析——以陕西省宁强县为例

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干旱地区农业研究 2012年第2期30卷 196-200页

作者：兰敏西北农林科技大学资源环境学院陕西杨凌712100

为了给秦巴山区宁强县的水土保持与土壤侵蚀防治提供科学依据,本研究利用遥感影像解译和GIS技术,得到研究区土地利用现状、植被覆盖和数字高程模型(DEM)等数据,并利用USLE模型计算研究区的土壤侵蚀模数。结果表明,研究区的土壤侵蚀面积... 详细信息

为了给秦巴山区宁强县的水土保持与土壤侵蚀防治提供科学依据,本研究利用遥感影像解译和GIS技术,得到研究区土地利用现状、植被覆盖和数字高程模型(DEM)等数据,并利用USLE模型计算研究区的土壤侵蚀模数。结果表明,研究区的土壤侵蚀面积轻度占47.015%,中度占33.36%,强度占12.53%。土壤侵蚀严重的地区主要分布在研究区的东北部,并且也是灌溉水田、水浇地、旱地和菜地分布的区域;本研究还运用GIS和遥感技术,选用通用土壤流失方程(USLE)成功估算了宁强县的侵蚀模数及各种侵蚀等级面积,研究结果与二调结果相符合。

关键词： GIS USLE 土壤侵蚀秦巴山区宁强县

Path-dependent speciation in dynamic fitness landscapes

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Zoological Research(Diversity and Conservation) 2024年第2期1卷 133-140页

作者： min-lan Li Chao Wang Rui-Wu Wang School of Ecology and Environment Northwestern Polytechnical UniversityXi’anShaanxi 710072China School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’anShaanxi 710072China

Species is a fundamental concept in evolutionary biology and ***,existing species definitions are often influenced by artificial factors or are challenging in practical application,leading to confusion in species *** to uncertain environmental changes and random genetic drift,the fitness expectations of a population may shift,causing species to evolve to a new evolutionary state based on their current instantaneous fitness within a dynamic fitness *** contrasts with the classic static fitness landscape,where fitness expectations are *** a dynamic fitness landscape,speciation may exhibit path dependence,where the evolution of traits follows a probabilistic path,creating feedback that shapes evolutionary *** path-dependent evolutionary mechanism suggests that species survival within an ecosystem is not directly determined by their fitness but by the probability of their evolutionary *** model also indicates that species can coexist with varying probabilities under limited environmental ***,new species,cryptic species,or sympatric species may emerge via path-dependent evolutionary *** this framework,we developed a mathematical species concept,which may guide future species classification methodologies.

关键词： Biodiversity Ecological/evolutionary model Fitness landscape Stochastic process Path dependence