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加强基础性研究 促进科技队伍的发展
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作者 王田均 《科技.人才.市场》 1995年第6期54-55,共2页
建立社会主义市场经济体制后,在新科技体制中基础研究应该占据什么样的位置?在市场经济的条件下是否有必要把更多的财力、物力投放到基础研究上去?有人认为“基础研究远水解不了近渴”.有人提出“战后日本基础性研究薄弱但经济搞上去了... 建立社会主义市场经济体制后,在新科技体制中基础研究应该占据什么样的位置?在市场经济的条件下是否有必要把更多的财力、物力投放到基础研究上去?有人认为“基础研究远水解不了近渴”.有人提出“战后日本基础性研究薄弱但经济搞上去了,英国基础性研究实力雄厚但经济下去了”.这些观点实际上是把发展市场经济和加强基础研究对立起来.还有的人则担心市场经济的浪潮会冲击和削弱基础研究.我们认为,我国发展市场经济不仅不能消弱、而且必须加强基础性研究.市场经济的本质是把竞争机制引入经济领域,而自然科学基础性研究是经济竞争力的发动机.没有强大的基础性研究作为支撑,不可能有持久的竞争力. 展开更多
关键词 础性研究 科技队伍 国家自然科学基金 市场经济 高校 教师
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The automobile steel of the third generation in B-pillar reinforced panel 被引量:2
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作者 Du Huijun Li Shuli +2 位作者 Yang Jie Yang Hongxin Bai Kebin 《Engineering Sciences》 EI 2012年第6期20-22,共3页
The fundamental research and industry, trials of the third generation automobile steel QP980 were introduced in this paper, including chemical ingredient, mechanical properties, microstructure, forming limit and basic... The fundamental research and industry, trials of the third generation automobile steel QP980 were introduced in this paper, including chemical ingredient, mechanical properties, microstructure, forming limit and basic perform- ance parameters. The application of QP steel of the B-pillar was researched, and the QP980, DP600 and hot forming steel were compared in the aspect of formability, safety and cost. The resuhs showed that the QP980 replacing DP600 steel single piece carl reduce the weight by 2.4 kg. The security and performance is basically the same as that of hot forming steel using 22MnB5, and the cost is reduced by 30 %. 展开更多
关键词 the third generation automobile steel B-pillar reintorced panel boron steel
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Fundamental Study on the Production of "Hyper Wood Pellet"——Effect of Torrefaction Condition on Grinding and Pelletizing Properties 被引量:1
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作者 Takahiro Yoshida Tetsuya Sano +3 位作者 Takashi Nomura Hideki Gensai Hiroki Watada Seiji Ohara 《Journal of Energy and Power Engineering》 2013年第4期705-710,共6页
In order to upgrade the conventional wood pellet, Japanese softwood and hardwood chips were torrefied at around 200-350℃, and pelletized. The characteristics of the torrefied material/pellets such as their calorific ... In order to upgrade the conventional wood pellet, Japanese softwood and hardwood chips were torrefied at around 200-350℃, and pelletized. The characteristics of the torrefied material/pellets such as their calorific value, grinding energy, pelletizing energy and elemental composition, were also evaluated in this study. The calorific value rose with increasing torrefaction temperature and exceeded 25 MJ/kg (an increase of nearly 40% compared to the untreated state) for torrefaction at around 350℃. The grinding energy greatly decreased with increasing torrefaction temperature, and the reduction was larger for Japanese oak hardwood chips. The pelletization energy for the torrefied material tended to be slightly smaller than in the untreated case. People named such torrefied pellet as "hyper wood pellet". 展开更多
关键词 Wood pellets TORREFACTION calorific value.
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Analysis of Irrigation Systems Employing Comparative Performance Indicators: A Benchmark Study for National Irrigation and Communal Irrigation Systems in Cagayan River Basin
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作者 Jeoffrey Lloyd Reyes Bareng Orlando Florendo Balderama Lanie Alejandro Alejo 《Journal of Agricultural Science and Technology(A)》 2015年第5期325-335,共11页
Comparative performance analysis of four irrigation schemes within Cagayan River Basin was assessed using comparative performance indicators between the years 2008 and 2012. The objectives were to establish benchmarks... Comparative performance analysis of four irrigation schemes within Cagayan River Basin was assessed using comparative performance indicators between the years 2008 and 2012. The objectives were to establish benchmarks for both productivity and performance of irrigation schemes along the valley and to inquire whether small schemes function better than large schemes. The performance evaluation study of the systems composed of three general performance indicators, based on three domains-(1) system operation performance; (2) agricultural productivity and economics; (3) financial performance. Each indicator was assessed based on the prescribed descriptors used by the International Water Management Institute (IWMI) and Food and Agriculture Organization (FAO). Analysis showed an overall system performance efficiency of 59%, 55%, 47% and 36% for Magat River Integrated Irrigation System (MARI1S), Lucban, Garab and Divisoria Communal Irrigation Systems (CIS), respectively. In terms of annual productivity performance, Lucban CIS dominates the three other systems with 0.35 kg/m3, which was classified as moderately performing system, while the rest were classified with low productivity index. Financial sustainability of the systems were extremely poor with cost recovery ratio of 0, 0.33, 0.41 and 0.49 for Divisoria, Garab, Lucban and MARIIS, respectively, which were exceptionally below the standard value of at least one. Also, analysis of the indicators revealed that on average, large schemes performed similarly to small-scale schemes, but small schemes were more variable, particularly in input-use efficiency. The benchmarking study will provide strategic information to policy makers of agricultural and irrigation agencies on the existing weaknesses of irrigation systems in the country and determine in a more quantifiable terms levels of potential improvement and intervention targets. 展开更多
关键词 Communal and national irrigation systems performance benchmarking small and large reservoir schemes.
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Phase engineering of two-dimensional transition metal dichalcogenides 被引量:10
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作者 Yao Xiao Mengyue Zhou +2 位作者 Jinglu Liu Jing Xu Lei Fu 《Science China Materials》 SCIE EI CSCD 2019年第6期759-775,共17页
Two-dimensional(2D) transition metal dichalcogenides(TMDs) have gained much attention in virtue of their various atomic configurations and band structures.Apart from those thermodynamically stable phases, plenty of me... Two-dimensional(2D) transition metal dichalcogenides(TMDs) have gained much attention in virtue of their various atomic configurations and band structures.Apart from those thermodynamically stable phases, plenty of metastable phases exhibit interesting properties. To obtain 2D TMDs with specific phases, it is important to develop phase engineering strategies including phase transition and phaseselective synthesis. Phase transition is a conventional method to transform one phase to another, while phase-selective synthesis means the direct fabrication of the target phases for2D TMDs. In this review, we introduce the structures and stability of 2D TMDs with different phases. Then, we summarize the detailed processes and mechanism of the traditional phase transition strategies. Moreover, in view of the increasing demand of high-phase purity TMDs, we present the advanced phase-selective synthesis strategies. Finally, we underline the challenges and outlooks of phase engineering of 2D TMDs in two aspects-high phase purity and excellent controllability. This review may promote the development of controllable phase engineering for 2D TMDs and even other2D materials toward both fundamental studies and practical applications. 展开更多
关键词 phase engineering transition metal dichalcogenides phase transition phase-selective synthesis
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Studying the genetic basis of speciation in high gene flow marine invertebrates 被引量:1
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作者 Grant H. POGSON 《Current Zoology》 SCIE CAS CSCD 2016年第6期643-653,共11页
A growing number of genes responsible for reproductive incompatibilities between species (barrier loci) exhibit the signals of positive selection. However, the possibility that genes experiencing positive selection ... A growing number of genes responsible for reproductive incompatibilities between species (barrier loci) exhibit the signals of positive selection. However, the possibility that genes experiencing positive selection diverge early in speciation and commonly cause reproductive incompatibilities has not been systematically investigated on a genome-wide scale. Here, I outline a research program for studying the genetic basis of speciation in broadcast spawning marine invertebrates that uses a priori genome-wide information on a large, unbiased sample of genes tested for positive selection. A targeted sequence capture approach is proposed that scores single-nucleotide polymorphisms (SNPs) in widely separated species populations at an early stage of allopatric divergence. The targeted capture of both coding and non-coding sequences enables SNPs to be characterized at known locations across the genome and at genes with known selective or neutral histories. The neutral coding and non-coding SNPs provide robust background distributions for identifying Fsm-outliers within genes that can, in principle, identify specific mutations experiencing diversifying selection. If natural hybridization occurs between species, the neutral coding and noncoding SNPs can provide a neutral admixture model for genomic clines analyses aimed at finding genes exhibiting strong blocks to introgression. Strongylocentrotid sea urchins are used as a model system to outline the approach but it can be used for any group that has a complete reference genome available. 展开更多
关键词 barrier loci Bobzhansky-Muller incompatibilities FsToutliers genome scan INTROGRESSION positive selection sequence capture speciation.
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A physical mechanism based investigation on the elasto-plastic-damage behavior of anisotropic aluminum alloys under finite deformation
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作者 CHEN Cen LIANG NaiGang +1 位作者 LIU Fang FU Qiang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第3期400-410,共11页
The elasto-plastic-damage behavior of anisotropic aluminum alloys is investigated under finite deformation using a physical mechanism based constitutive model.With an application to the structural calculation,the pres... The elasto-plastic-damage behavior of anisotropic aluminum alloys is investigated under finite deformation using a physical mechanism based constitutive model.With an application to the structural calculation,the present model is used to describe and analyze the mechanical response of anisotropic 6260-T6 aluminum alloy extrusions.For the tensile specimens extracted along three different material orientations from the extruded aluminum profile,twelve simulations are carried out covering four different specimen geometries.The simulation results in force-displacement response and central logarithmic axial strain evolution are compared with experimental results.From the comparisons,it can be concluded that the present model has the capacity to describe the behavior of anisotropic material.From the force-displacement curves,the anisotropy is observed in different material orientations,and the physical mechanism of anisotropy is analyzed. 展开更多
关键词 elasto-plastic-damage behavior ANISOTROPY physical mechanism finite deformation constitutive theory componentassembling model
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