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引气轻骨料混凝土配合比试验研究及施工技术

施工技术 2009年第S1期38卷 361-363页

作者：王晓辉孙兴娣北京市建设职工大学北京100026 北京城市建设学校北京100026

为解决目前土木工程中应用轻骨料混凝土的部分困难和促进引气轻骨料混凝土在土木工程上的实际应用,采用绝对体积法得到引气轻骨料混凝土的初步配合比,进而通过正交试验设计和大量的试验数据分析,得到强度为30MPa,含气量在4.8%左右的引... 详细信息

为解决目前土木工程中应用轻骨料混凝土的部分困难和促进引气轻骨料混凝土在土木工程上的实际应用,采用绝对体积法得到引气轻骨料混凝土的初步配合比,进而通过正交试验设计和大量的试验数据分析,得到强度为30MPa,含气量在4.8%左右的引气轻骨料混凝土的配制技术,同时也对此混凝土的施工技术作了简单介绍。

关键词：引气轻骨料混凝土配合比正交试验设计施工技术

Paleomagnetic Excursions Recorded in the Yanchi Playa in Middle Hexi Corridor, NW china Since the Last Interglacial

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Journal of Mountain Science 2004年第2期1卷 128-142页

作者： YANGTaibao YUYongtao LIJijun ANCongrong LIUJinfeng ZHANGJunyan KeyLaboratoryofWesternEnvironmentalChanges ChineseMinistryofEducationLanzhouUniversityLanzhou730000China DepartmentofGeography SchoolofGeosciencesNanjingNormalUniversityNanjing210097China InstituteofGeologyandGeophysics ChineseAcademyofSciencesBeo＇ing100029China

Paleomagnetic determinations on lithological profiles of two paralleled[( )-275(long )]drilling cores covering the past 130 kyr B.P., GT40 and GT60, from the Yanchi Playa in the arid Northwestern china, indicate that a series of pronounced paleomagnetic excursions have been documented. By correlating our results with published regional and worldwide reports, 4 excursion events out of 10 apparent reversal signals (labeled from GT-1 to GT-10) were identified as excursion events coeval with the Mono Lake Event ([(28.4)( )]kyr~[(25.8)( )]kyr), Laschamp Event ([(43.3)( )]kyr^40.5 kyr), Gaotai Event (82.8 kyr~[(72.4)25( )]kyr) and the Blake Event (127.4 kyr^113.3 kyr), respectively. GT-9 correlates with the above-mentioned Gaotai Event, GT-7 and GT-6 correspond to two stages of the Laschamp Event and GT-5 to the Mono Lake Event. It is noteworthy that the so-called Gaotai Event has not been reported as a pronounced paleomagnetic excursion in the Northwestern china. Every magnetic excursion event corresponds to paleointensity minima, anteceding those established abrupt paleoclimatic change events, such as the Younger Drays and the Heinrich Events (H1-H6)[(. )-250( )]Here,[( )-250( )]we tentatively[( )-250( )]propose that these geomagnetic excursions/reversals can be viewed as precursors to climate abruptness. During the transitional stages when the earths magnetic field shifted between a temporal normal and a negative period, the earths magnetic paleointensity fell correspondingly to a pair of minima. Although more precise chronology and more convincing rock magnetic parameter determinations are essentially required for further interpretation of their intricate coupling mechanism, these results may have revealed, to some extent, that the earths incessantly changing magnetic field exerts an strong influence on the onset of saw-tooth shaped abrupt climate oscillations through certain feedback chains in arid Central Asia or even North Hemispheric high latitude regions.

关键词： Paleomagnetism geomagnetic excursion the Late Pleistocene arid Northwestern china

Vertical adaptive radiation in ocean Prochlorococcus:Evolutionary implications of the Ch1 b/a ratio from molecular evidence

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Progress in Natural Science:Materials International 2009年第11期19卷 1561-1568页

作者： Song Qin~(a,*),Yinchu Wang~(a,b) a Yantai Institute of Coastal Zone Research for Sustainable Development,Chinese Academy of Sciences,Yantai 264003,china b Graduate university of Chinese Academy of Sciences,beijing 100049,china [a]Yantai Institute of Coastal Zone Research for Sustainable Development Chinese Academy of Sciences Yantai 264003 China [b]Graduate university of Chinese Academy of Sciences Beijing 100049 China

Prochlorococcus is a marine cyanobacterium of global *** ecotypes are adapted to either high-light(HL) or low-light (LL) *** ratio between chlorophyll(Chl) a and b is a distinguishing characteristic of these two ***,how this ratio evolved in Prochlorococcus during this ecotype differentiation remains *** analyses reveal that the ancestor of Prochlorococcus was typically low-light *** LL ecotype showed a stagnant evolution,and the HL ecotype was recently *** was an adaptive radiation after directional evolution in the Chl bla ratio *** in chlorophyllide a oxygenase(CAO) and positive selection on Clp protease contributed to the directional evolution of *** recombinant fragments of CAO were correlated with a large group of shared coevolving *** of positive selection was found in both subunits of *** bla ratio evolution,as annotated by molecular evidence,appears to be among the crucial reasons that explain how Prochlorococcus has become the dominant photosynthetic organism in the ocean.

关键词： Prochlorococcus Ch1 b/a ratio Adaptive evolution Trait evolution Ecotype differentiation

A Survey of Stickiness of Agriculture Knowledge Acquisition in china

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A Survey of Stickiness of Agriculture Knowledge Acquisition ...

Microstructures and properties of molybdenum wires doped with La

亚洲精细农业与计算机农业应用联合大会

作者： Weizhe Feng 1 Daoliang Li 2 Yanqing Duan 3 Zetian Fu 2 1 International College at beijing china Agricultural university beijing P. R. china 100083 2 College of Information and Electrical Engineering china Agricultural university beijing P. R. china 100083 3 Business school university of Bedfordshire Luton LU1 3JU UK

The concept of stickiness in this study was borrowed from information research literature, which indicated the complex and difficulties in all process of knowledge transfer that including knowledge acquisition. To reveal the stickiness of agriculture knowledge acquisition in china, a survey was conducted of agriculture related websites in china. Firstly, an intensive literature review was done for collecting attributes closely associated with agriculture knowledge and its acquisition process. Secondly, these attributes were cate- gorized and transformed into questionnaire and surveyed in 14 provinces in china. Thirdly, the data were tested with principal component analysis methods. As results, this study concluded that four factors that may affect the stickiness of agriculture knowledge, namely, difficulty, special tacitness, available explicitness, and proven knowledge;five factors that may affect stickiness of agriculture experts. They include attitudes, professional, expression capability, teamwork, and protectiveness;and five factors that may affect stickiness of agriculture institutions, attitudes, service orientation, distance, protectiveness, and professional. In conclusion, it was suggested that the three groups of principal factors can be used to guide the planning and assessment of ICT-based knowledge projects in rural areas. The study also highlighted a new area for ICT-based information and knowledge transfer research.

关键词： stickiness agriculture knowledge acquisition principal component analysis

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中国有色金属学会会刊：英文版 1994年第3期4卷 57-62,66页

作者： Zhou, Meiling Li , Jun Zuo , Tieyong(Department of Materials Science and Engineering,beijing Polytechnic university, beijing 100022)(Universiyt of Science and Technology beijing, beijing 100083)(Central South university of Technology, Changsha 410083)

ＭＩＣＲＯＳＴＲＵＣＴＵＲＥＳＡＮＤＰＲＯＰＥＲＴＩＥＳＯＦＭＯＬＹＢＤＥＮＵＭＷＩＲＥＳＤＯＰＥＤＷＩＴＨＬａＺｈｏｕ，Ｍｅｉｌｉｎｇ；Ｌｉ，Ｊｕｎ；Ｚｕｏ，Ｔｉｅｙｏｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌ... 详细信息

ＭＩＣＲＯＳＴＲＵＣＴＵＲＥＳＡＮＤＰＲＯＰＥＲＴＩＥＳＯＦＭＯＬＹＢＤＥＮＵＭＷＩＲＥＳＤＯＰＥＤＷＩＴＨＬａＺｈｏｕ，Ｍｅｉｌｉｎｇ；Ｌｉ，Ｊｕｎ；Ｚｕｏ，Ｔｉｅｙｏｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅ...

关键词： molytxlenum La microstructure recrystallization strengthening toughening

Study on the knowledge innovation performance of the high-tech virtual industry cluster

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Study on the knowledge innovation performance of the high-te...

Cardioprotective effects of ghrelin and des-octanoyl ghrelin on myocardial injury induced by isoproterenol in rats

2011年全国电子信息技术与应用学术会议

作者： Shao Hai-jing Liu Yan-Ping school of Economics and Management beijing Jiaotong university beijing,china

As for knowledge innovation,it is the important factor for the high-tech virtual industry *** paper analyses the style and structure of the knowledge innovation,establishes the comprehensive evaluation model to calculate the performance of the high-tech virtual industry cluster,which provide the basis and strategic theories for the member to know the mechanism of the knowledge management of HTVIC.

关键词： high-tech virtual industry cluster knowledge innovation performance gray correlation model

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Acta Pharmacologica Sinica 2006年第5期27卷 527-535页

作者： LLian LI~2 Li-ke ZHANG~5 Yong-zheng PANG~(2.4) Chun-shui PAN~(3.4) Yong-fen QI~(3.4) Li CHEN~4 Xian WANG~(3,4) Chao-shu TANG~(3,4) Jing ZHANG~(2,4,6) ~2Institute of Cardiovascular Research,Peking university First Hospital,beijing 100034,china:~3Department of Physiology and Pathophysiology,Peking university Health Science Center,beijing 100083,china ~4Key Laboratory of the Ministry of Education on Molecular Cardiology,beijing 100083,china:~5Department of Pathophysiology,Capital university of Medicine,beijing 100054,china lnstituteofCardiovascularResearch PekingUniversityFirstHospitalBeijing100034China DepartmentofPathophysiology CapitalUniversityofMedicineBeijing100054China

Aim:To determine the cardioprotective action of ghrelin and des-octanoyl ghrelinin rats with isoproterenol-induced myocardial ***:Rats were subcu-taneously injected with isoproterenol （ISO;20,10,and 5 mg/kg） on d 1,2 and 3,respectively,and then 3 mg/kg for the next 7d with or without ghrelin or des-octanoyl-ghrelin （100μg/kg,twice daily）.Plasma ghrelin and growth hormonelevels were assayed using radioimmunoassay *** hormone secreta-gogue receptor （GHSR） and ghrelin mRNA were determined using *** binding capacity and the affinity for [3H]ghrelin were determined by re-ceptor binding ***:Compared with controls,ISO-treated rats showedsevere myocardial injury,cardiomegaly,infarction-like necrosis and massive fi-brosis with increases in irradiated-ghrelin （ir-ghrelin） content in plasma by 67%and myocardia by 66% and in the mRNA level in the myocardia by 93% （P<0.01）.ISO-treated rats had 95% （P<0.01） higher GHSR mRNA levels in the *** maximal binding capacity of [3H]ghrelin for myocardial sarcolemma was higherin ISO-treated rats than in *** administration improved cardiac func-tion and ameliorated cardiomegaly and attenuated myocardial lipid peroxidationinjury and relieved cardiac fibrosis as compared with ISO treatment ***-istration of des-octanoyl ghrelin effectively antagonized ISO-induced myocardialinjury and improved all parameters ***,the therapeutic effect ofdes-octanoyl ghrelin was significantly weaker than that of *** plasmagrowth hormone level increased markedly,by 1.5-fold （P<0.01）,with ghrelinadministration as compared with that in controls,but was unaltered in the des-octanoyl ghrelin ***:Myocardial ghrelin and GHSR were up-regulated during ISO-induced myocardial *** protective effect of ghrelinagainst ISO-induced cardiac function injury and fibrosis was more potent thanthat of des-octanoyl ghrelin,which suggests that ghrelin could be an endog

关键词： ghrelin des-octanoyl ghrelin myocardium fibrosis isoproterenol

Simulation of the Response of Glass Window Under Blast Load

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Transactions of Tianjin university 2008年第B10期14卷 504-510页

作者：王仲琦宫广东张彦春白春华 The State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology china Criminal Police Institute

In the investigation of accidental explosion scene, the damage on the glass is one of the typi-cal traces which can be used to decide the characteristic of the explosion source. To analyze the re-sponse of glass under the blast load, a numerical model was developed. In the model, the brittleness glass model was adopted. A‘node release’method, which had some special merits compared with the erosion method was used to simulate the rupture of the glass In the calculation, several problems which play major role in the response of the glass were discussed. The velocity and the displacement of the glass fragment were two major factors. The numerical results are very helpful for the design and hazard assessment.

关键词： glass blast load dynamic response

A Novel Differential Evolution Algorithm Based On Simulated Annealing

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A Novel Differential Evolution Algorithm Based On Simulated ...