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91.
目的: 观察法舒地尔对大鼠脑缺血再灌注损伤炎症反应的影响,探讨其抗炎机制。方法: 大脑中动脉线栓法(MCAO)制作大鼠局灶性脑缺血再灌注损伤模型,缺血1.5h再灌注24h。法舒地尔术前腹腔注射给药15mgkg,术后12h再次给药。术后对大鼠神经功能进行评分,TTC染色观察脑梗死体积;用干湿重法测定脑含水量;分光光度法测定髓过氧化物酶(MPO)活性;伊文思兰法(EB)测定血脑屏障的损伤程度;免疫组化检测大鼠脑缺血区细胞间黏附分子-1(ICAM-1)、血管细胞黏附分子-1(VCAM-1)、NF-κBp65的表达;ELISA法检测IL-8的含量;Westernblot法检测单核细胞趋化蛋白-1(MCP-1)和核抽提物中NF+κBp65蛋白的表达;RT-PCR检测NF-κBp65mRNA的表达。结果: 法舒地尔能明显改善脑缺血再灌注损伤大鼠神经缺陷症状,缩小脑梗死体积,明显降低缺血侧脑组织的含水量、EB含量及MPO活性;显著抑制ICAM-1.VCAM-1.L8和MCP-1蛋白的表达;降低NF-κBp65mRNA和蛋白的表达;减少脑组织核抽提物中NF+κBp65的蛋白量(K0.05vsMCAO组)。结论: 法舒地尔通过抑制NF-κBp65的活化进而抑制黏附分子及趋化因子的表达,减轻脑缺血再灌注损伤的炎症反应。 相似文献
92.
针对上海金山区山阳镇农村河道现状进行了分析,阐述了河道破坏的原因以及对其进行生态护岸建设的必要性,并介绍了几种适合山阳镇河道的生态护岸的基本形式,以期指导该地区农村河道改造工作。 相似文献
93.
94.
用自制金属氧化物粒子电极在三维电极反应器中降解酚类,试验分析曝气流量、进水pH、电解电压、粒子电极填充量及反应时间对三维电极氧化降解炼油废水中酚类去除效果的影响,得出最佳反应条件:曝气流量为0.5L/min,不调节进水pH6.5,电解电压12 V,粒子电极投加量为100g,反应时间为60 min,在此条件下对酚类浓度为... 相似文献
95.
F. Ancona 《Journal of Dynamical and Control Systems》1997,3(2):205-240
An extension of the classical Pontryagin maximum principle for Mayer problems without terminal constraints, subject to affine
control systems
, is proved. In connection with a suitable dilation on the state space ℝ
n
, we introduce a class of “homogeneous tangent vectors” which provide a nonlinear, high-order approximation of the attainable
set in the case where the usual linear approximation proves to be inadequate. By studying control variations which generate
homogeneous tangent vectors, we derive new necessary conditions for optimality that are particularly effective for basically
nonlinear optimal control problems where other high-order tests provide no conclusive information.
This research was partially supported by Istituto Nazionale di Alta Matematica “F. Severi.” 相似文献
96.
In both [3] and [8], the authors review the implementation of the basic operations in interval arithmetic, and in particular discuss the different approaches given in the literature for interval division when the divisor interval contains zero. In these papers, and in the references therein, the basic operations are defined for real or extended real interval operands.Division by an interval containing zero is a special case of an interval function for which the input arguments contain points outside the domain of the underlying point function. A number of approaches exist in the literature, [7], [12], to remove restrictions on the domain of interval functions and hence obtain a closed, exception-free interval system.In this paper, we present an alternative approach to remove restrictions on the domain of interval functions and to guarantee the inclusion property in all situations, even when some input intervals contain points that lie outside the domain of the underlying point function. To achieve this, we allow for the (efficient) set-based representation of non-real results. The computed intervals are sharp, yet contain more information and the resulting interval system is closed and exception-free. We also show how the presented ideas can be implemented in an interval arithmetic library. The performance overhead is negligible compared to the fact that the implementation using the new approach offers 100% reliability in return.The structure of the paper is as follows. We set off with a motivating example in Sect. 1. In Sect. 2, we review various approaches to interval division and then introduce vset-division of real intervals, based on the newly introduced concept of value set or vset. In Sect. 3, we give a formal definition of real vset-intervals and arithmetic on these intervals. We prove a number of essential properties and point out the likenesses and differences with other approaches. Finally, in Sect. 4, we discuss the implementation of vset-interval arithmetic in a floating-point context.Research assistant FWO Vlaanderen. 相似文献
97.
98.
In 1998, the research ministers of France, Italy and Spain have decided to set up a group of advisors for the definition of a common R&D European platform on accelerator driven systems (ADS). The advisors in turn, have established a Technical Working Group (TWG), chaired by Professor Carlo Rubbia, and now extended to the most part of the European Union member countries, in order to identify the critical technical issues for which R&D is needed. The recommendations of the TWG, included in the recently issued document `A European roadmap for developing ADS for nuclear waste incineration' [April 2001] clearly indicate the need to design and operate, approximately in 12-15 years, an XADS at a sufficiently large scale to assess the feasibility of an industrial ADS for transmutation of nuclear waste. The European Community, through the 5th Framework Program, has launched a large program on partitioning and transmutation. This program which includes R&D and preliminary design will constitute a reference for the choice of the technical solutions to be pursued forward during the 6th Framework Program. In Italy, since early 1998, the ENEA (National Research Organization for Innovative Energy), INFN (National Institute for Nuclear Physics), CRS4 (Research Institute) and Ansaldo have set up a team, led by Ansaldo, to design an 80 MWth XADS. The results obtained so far allow a consistent XADS configuration to be outlined. The main issues investigated and the associated solutions adopted are concisely described in the paper. 相似文献
99.
In the framework of the Italian research program TRASCO for ADS, the device ORE has been designed and operated at the ENEA C.R. Brasimone in order to study the kinetics of lead oxide reduction by flowing hydrogen, diluted at 3% by volume in argon. From the measurement of water generated by the reaction between hydrogen and lead oxide, the rate of PbO reduction was determined and a first estimation of the activation energy was found. The experimental results so far achieved in terms of reaction rate, activation energy and kinetic constant, as well as the experimental set-up and the methodology, are here summarised and discussed. 相似文献
100.
Lili Tian 《Computational statistics & data analysis》2006,51(2):1156-1162
The inverse Gaussian (IG) distribution is an ideal candidate for modelling positive, right-skewed data due to the fact that its inference theory and methodology bear a striking resemblance to the normal theory and methods. For testing equality of several IG means under the assumption of equal scale parameters, there exists the ANORE (analysis of reciprocal) F test, which is analogous to the ANOVA F test for the normal distribution. In this article, the concept of generalized P-value, introduced by Tsui and Weerahandi [1989. Generalized P-values in significance testing of hypotheses in the presence of nuisance parameters. J. Amer. Statist. Assoc. 84, 602-607], is applied for testing equality of several IG means for the general cases without the assumption of homogeneity. Simulation results indicate that the proposed test has excellent type I error control under both heterogeneity and homogeneity, whereas the type I error probabilities of the ANORE test can be much larger than the nominal level under heterogeneity. The proposed procedure is illustrated using two examples. 相似文献