检索结果-南通市图书馆

Liquid metal as energy transportation medium or coolant under harsh environment with temperature below zero centigrade

引用

Frontiers in Energy 2014年第1期8卷 49-61页

作者： Yunxia ga0 Lei WANG Haiyan LI Jing LIU Key Lab of Cryogenics and Beijing Key Lab of CryoBiomedicalEngineering Technical Institute of Physics and Chemistry ChineseAcademy of Sciences Beijing 100190 China Department of Biomedical Engineering School of Medicine TsinghuaUniversity Beijing 100084 China

The current highly integrated electronics and energy systems are raising a growing demand for more sophisticated thermal management in harsh environments such as in space or some other cryogenic environment. Recently, it was found that room temperature liquid metals （RTLM） such as gallium or its alloys could significantly reduce the electronics temperature compared with the conventional coolant, like water, oil or more organic fluid. However, most of the works were focused on RTLM which may subject to freeze under low temperature. So far, a systematic interpretation on the preparation and thermal properties of liquid metals under low temperature （here defined as lower than O^C） has not yet been available and related applications in cryogenic field have been scarce. In this paper, to promote the research along this important direction and to overcome the deficiency of RTLM, a comprehensive evaluation was proposed on the concept of liquid metal with a low melting point below zero centigrade, such as mercury, alkali metal and more additional alloy candidates. With many unique virtues, such liquid metal coolants are expected to open a new technical frontier for heat transfer enhancement, especially in low temperature engineering. Some innovative ways for making low melting temperature liquid metal were outlined to provide a clear theoretical guideline and perform further experiments to discover new materials. Further, a few promising applied situations where low melting temperature liquid metals could play irreplaceableroles were detailed. Finally, some main factors for optimization of low temperature coolant were summarized. Overall, with their evident merits to meet various critical requirements in modem advanced energy and power industries, liquid metals with a low melting temperature below zero centigrade are expected to be the next- generation high-performance heat transfer medium in thermal managements, especially in harsh environment in space.

关键词： liquid metal cryogenics low melting point,thermal management aircraft liquid cooling spaceexploration

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A Note on Solutions for Asymptotically Linear Elliptic Systems

引用

Acta Mathematicae Applicatae Sinica 2008年第3期24卷 511-522页

作者： Lei-ga Zhao Department of Mathematics Beijing University of Chemical Technology 100029 Beijing China Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China Department of Mathematics Yunnan Normal University Kunming 650092 China

In this paper, we are concerned with the elliptic system of{ -△u＋V（x）u=g（x,v）, x∈R^N, -△v＋V（x）v=f（x,u）, x∈R^N, where V（x） is a continuous potential well, f, g are continuous and asymptotically linear as t→∞. The existence of a positive solution and ground state solution are established via variational methods.

关键词： Elliptic system ground state solution variational methods concentration-compactness principle

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

STI571 combined with vincristine greatly suppressed the tumor formation of multidrug-resistant K562 cells in a human-nude mice xenograft model

引用

Chinese Medical Journal 2006年第11期119卷 911-918页

作者： ga0 Lei CHEN Li FEI Xin-hong QIU Hui-ying ZH0U Hong WANG Jian-min Department of Hematology Changhai Hospital Second Military Medical University Shanghai 200433 China

Background The development of the targeted signal transduction inhibitor STI571 has prompted us to treat chronic myeloid leukemia in different ways. Since STI571 may reverse multidrug-resistance of K562/MDR cells in vitro, we studied the effect of STI571 on multidrug-resistant K562 cells in vivo. Methods Multidrug-resistant human leukemia cell line K562-n/VCR expresses both bcr/abl fusion gene and multi-drug resistance （mdrl） gene. It is a vincristine resistant cell line subcloned from the vincristine （VCR） sensitive cell line K562-n induced by vincristine in vitro. K562-n and K562-n/VCR cells were inoculated subcutaneously into both sides of nude mice breast （5×10^6 cells/each） to establish a human leukemia xenograft model. The incidence and volume of tumor were observed. In the tumor-bearing nude mice, anti-tumor drugs vincristine, daunorubicin （DNR）, STI571, and STI571 plus VCR for the treatment of mdrl and bcr/abl double positive leukemia were studied respectively. Results The tumor incidence was 100% in the nude mice inoculated with either K562-n or K562-n/VCR. The transcription of the mdrl gene and expression of P-gp were negative in K562-n cells but positive in K562-n/VCR cells. The intracellular accumulation of DNR in K562-n cells was higher than that in K562-n/VCR cells （P〈0.05） The tumor incidence of K562-n/VCR cells in nude mice was much higher than that of K562-n cells in chemotherapy groups, and the mean volume of the tumors was also larger （P〈0.05）. STI571 combined with VCR significantly suppressed the proliferation of K562-n/VCR cells. Conclusions The MDR characteristics of K562-n/VCR in vivo were the same as in vitro. STI571 had a significant tumor-suppressing effect on VCR-sensitive leukemia ceils and a moderate effect on MDR leukemia cells. VCR combined with STI571 had an excellent tumor-suppressing effect on both K562-n/VCR and K562-n in the human-nude mice xenograft model.

关键词： K562 cells leukemia multidrug-resistance imatinib mesylate xenograft model antitumor assays

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Syntheses and Structures of Two Coordination Polymers Containing Macrocyclic Oxamide and Isophthalic Acid Derivatives

引用

Chemical Research in Chinese Universities 2012年第5期28卷 775-779页

作者： WU Lin SUN Ya-qiu LIU Xiao-xu ga0 Dong-zhao XU Yan-yan ZHANG Guo-ying Tianjin Key Laboratory of Structure and Performance for Functional Molecule College of ChemistryTianjin Normal UniversityTianjin 300387P.R.China

Two novel coordination polymers [Cd（NiL）（aipt）]（1） and [Mn（nipt）（NiL）2]？H2O（2）（NiL, H2L=2,3-dioxo- 5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien, H2aipt=5-aminoisophthalic acid, H2nipt=5-nitroisoph- thalic acid） were hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Compounds 1 and 2 consist of different 1D chains including both oxamide and 5-aminoisophthalate or 5-nitroisophthalic bridge. And all these chains were further interlinked via hydrogen bonds, resulting in a 2D architecture in compounds 1 and 2.

关键词： Macrocyclic oxamide complex 5-Aminoisophthalic acid 5-Nitroisophthalic acid Heterometallic complex Polynuclear complex

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Analysis and assessment of land desertification in Xinjiang based on RS and GIS

引用

Journal of Geographical Sciences 2004年第2期14卷 159-166页

作者： LIHu WANGXiaofeng ga0Yaqi DepartmentofUrbanandResourcesScience NanjingUniversityNanjing210093China DepartmentofGeography XinjiangNormalUniversityUrumqi830054China XinjiangForestryInvestigationandDesignInstitute Urumqi830002China

The land desertification in Xinjiang was monitored and analyzed based on RS and GIS techniques. Satellite data interpretation was adopted to obtain the general situation of Xinjiang’s land desertification in assistance with the sampling method and on-the-spot investigations. Related monitoring and investigations showed that Xinjiang was facing with severe wide range land desertification, and its desertified area made up 77.08% of the total monitoring area. As for land types, the desertified farmland accounted for 1.92% of the total monitoring area, desertified woodland 4%, desertified grassland 45%, and unused land 49%. Accordingly, as for desertification degrees, non-desertified land occupied 22.92%, weak desertified land 5.69%, medium-degree desertified land 16.58%, severe desertified land 33.19% and super severe desertified land 21.61%. Finally, as for inducing factors, wind-eroded desertification made up 58.23%, water-eroded desertification 8.69%, salinization desertification 6.52% and frozen-melt eroded desertification 3.64%. Xinjiang’s land desertification tended to get worse and the harnessing mission remained hard.

关键词： Xinjiang land desertification remote sensing GIS monitoring and analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Is management of acute traumatic brain injury effective？ A literature review of published Cochrane Systematic Reviews

引用

Chinese Journal of Traumatology 2012年第1期15卷 17-22页

作者： LEi Jin ga0 GUO JIANGJi-yao Neurosurgery Department of Renji Hospital Medical School of Shanghai JiaoTong University Shanghai Institute of Head Trauma Shanghai 200127 China

Objective：To evaluate all the possible therapeutic measures concerning the acute management of traumatic brain injury（TBI）mentioned in Cochrane Systematic Reviews published in the Cochrane Database of Systematic Reviews（CDSR）.Methods：An exhausted literature search for all published Cochrane Systematic Reviews discussing therapeutic rather than prevention or rehabilitative interventions of TBI was *** retrieved such databases as CDSR and Cochrane Injury Group,excluded the duplications,and eventually obtained 20 results,which stand for critical appraisal for as many as 20 different measures for TBI *** important data of each systematic review,including total population,intervention,outcome,etc,were collected and presented in a designed ***,we also tried to find out the possible weakness of these clinical trials included in each ***：Analysis of these reviews yielded meanfuling observations：（1）The effectiveness of most ordinary treatments in TBI is inconclusive except that corticosteroids are likely to be ineffective or harmful,and tranexamic acid,nimodipine and progesterone show a promising effect in bleeding trauma,traumatic subarachnoid hemorrhage,TBI or severe TBI.（2）A majority of the systematic reviews include a small number of clinical trials and the modest numbers of patients,largely due to the uncertainty of the effectiveness.（3）The quality of most trials reported in the systematic reviews is more or less questionable.（4）In addition,lots of other complex factors together may lead to the inconclusive results demonstrated in the Cochrane Systematic ***：For clinical physicians,to translate these conclusions into practice with caution is *** medication and nursing care deserve additional attention as well and can be *** researchers,high quality trials with perfect design and comprehensive consideration of various factors are urgently required.

关键词： Brain injuries Meta-analysis Review Acute management

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Failure behavior of soil-rock mixture slopes based on centrifuge model test

引用

Journal of Mountain Science 2019年第8期16卷 1928-1942页

作者： WANG Teng ZHANG ga State Key Laboratory of Hydroscience and Engineering Tsinghua University

The stability of soil-rock mixtures(SRMs) that widely distributed in slopes is of significant concern for slope safety evaluation and disaster prevention. The failure behavior of SRM slopes under surface loading conditions was investigated through a series of centrifuge model tests considering various volumetric gravel contents. The displacement field of the slope was determined with image-based displacement system to observe the deformation of the soil and the movement of the block during loading in the tests. The test results showed that the ultimate bearing capacity and the stiffness of SRM slopes increased evidently when the volumetric block content exceeded a threshold value. Moreover, there were more evident slips around the blocks in the SRM slope. The microscopic analysis of the block motion showed that the rotation of the blocks could aggravate the deformation localization to facilitate the development of the slip surface. The high correlation between the rotation of the key blocks and the slope failure indicated that the blocks became the dominant load-bearing medium that influenced the slope failure. The blocks in the sliding body formed a chain to bear the load and change the displacement distribution of the adjacent matrix sand through the block rotation.

关键词： Soil rock mixture Slope stability Slope failure Centrifuge model test

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

利用集合均方根卡尔曼滤波反演重庆地区SO_2源排放

引用

环境科学研究 2018年第1期31卷 25-33页

作者：吴钲谢旻高阳华芦华赵磊高松重庆市气象科学研究所重庆401147 南京大学江苏南京210093

传统的"自下而上"清单方法估算的排放清单,其数据的准确性和时效性存在较大局限.基于集合均方根卡尔曼滤波的源清单反演方法,结合WRF-CMAQ(天气研究和预报模式-公共多尺度空气质量模型)被用于对以清华大学编制的2010年MEIC(中国多尺度... 详细信息

传统的"自下而上"清单方法估算的排放清单,其数据的准确性和时效性存在较大局限.基于集合均方根卡尔曼滤波的源清单反演方法,结合WRF-CMAQ(天气研究和预报模式-公共多尺度空气质量模型)被用于对以清华大学编制的2010年MEIC(中国多尺度排放清单模型)排放清单为基础制作的重庆地区SO_2排放源进行反演试验以解决准确性和时效性问题,试验时间段为2014年10月15—31日,重庆主城17个环境空气质量国控监测点ρ(SO_2)小时观测资料用于反演及检验.结果表明:该方法能够反演重庆地区SO_2源排放量,随着反演次数增加,基于反演排放源预报的ρ(SO_2)预报误差持续减小,反演4次后预报误差达到比较低的稳定的水平,其均方根误差均低于20μg/m^3.5次反演后SO_2源排放量用于2014年10月24—29日每天起始预报,其预报的站点、时间平均的均方根误差从100~400μg/m^3降至30μg/m^3以下.反演中应用局地化尺度减少集合取样误差影响,54与81 km两个局地化尺度反演结果对预报改善效果相当,表明主要影响重庆主城ρ(SO_2)的源排放位于主城及周边地区,也说明内源排放对重庆主城ρ(SO_2)起主要影响.反演后面源排放量主城区降幅约为30 kg/(d·km^2),周边地区减少10~20 kg/(d·km^2),主城区部分SO_2点源排放量降幅约为25 kg/(d·km^2),说明2010年MEIC排放清单高估了试验时段重庆地区的SO_2排放.

关键词： S02 WRF-CMAQ 源排放反演集合均方根卡尔曼滤波

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Centrifuge model tests on pile-reinforced slopes subjected to drawdown

引用

Journal of Rock Mechanics and Geotechnical Engineering 2020年第6期12卷 1290-1300页

作者： Sujia Liu Fangyue Luo ga Zhang State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing100084China

Piles are generally an effective way to reduce the risk of slope ***,previous approaches for slope stability analysis did not consider the effect of the piles coupled with the decrease of the water level(drawdown).In this study,a series of centrifuge model tests was performed to understand the deformation and failure characteristics of slopes reinforced with various pile *** the centrifuge model tests,the pile-reinforced slopes exhibited two typical failure modes under drawdown conditions:across-pile failure and through-pile *** the through-pile slope failure,a discontinuous slip surface was observed,implying that the assumption of the slip surface in previous stability analysis methods was *** test results showed that drawdown led to instability of the piles in cohesive soil,as the saturated cohesive soil failed to provide sufficient constraint for *** slope exhibited progressive failure,from top to bottom,during *** deformation of the piles was reduced by increasing the embedment depth and row number of *** addition,the deformation of soils outside the piles was influenced by the piles and showed a similar distribution shape as the piles,and the similarity degree weakened as the distance from the piles *** study also found that the failure mechanism of unreinforced and pile-reinforced slopes induced by drawdown could be described by coupling between the deformation localization and local failure,and it revealed that pile-reinforced slopes could reduce slope deformation localization during drawdown.

关键词： Slope Pile Drawdown Failure Reinforcement Centrifuge model test

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Simplified method for analyzing soil slope deformation under cyclic loading

引用

Journal of Rock Mechanics and Geotechnical Engineering 2022年第6期14卷 1967-1976页

作者： ga Zhang Yaliang Wang Fangyue Luo State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing100084China

Reasonable assessment of slope deformation under cyclic loading is of great significance for securing the safety of slopes. The observations of centrifuge model tests are analyzed on the slope deformation behavior under cyclic loading conditions. The potential slip surface is the key for slope failure and follows two rules:(i) the relative horizontal displacement along the potential slip surface is invariable at an elevation, and(ii) the soil along the slip surface exhibits the same degradation pattern. These rules are effective regardless of the location of the potential slip surface throughout the entire deformation process of a homogeneous slope, ranging from the initial deformation stage to the failure process and to the post-failure stage. A new, simplified method is proposed by deriving the displacement compatibility equation and unified degradation equation according to the fundamental rules. The method has few parameters that can be determined through traditional element tests. The predictions from the proposed method agree with the centrifuge test results with vertical loading and shaking table loading. This result confirms that the proposed method is effective in predicting the full deformation process of slopes under different cyclic loading conditions.

关键词： Soil slope Cyclic load Deformation Centrifuge model test Slice method

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：