首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   272篇
  免费   7篇
电工技术   5篇
化学工业   53篇
金属工艺   5篇
机械仪表   4篇
建筑科学   8篇
能源动力   24篇
轻工业   33篇
石油天然气   4篇
无线电   20篇
一般工业技术   55篇
冶金工业   21篇
原子能技术   2篇
自动化技术   45篇
  2023年   2篇
  2022年   8篇
  2021年   11篇
  2020年   8篇
  2019年   6篇
  2018年   11篇
  2017年   11篇
  2016年   12篇
  2015年   8篇
  2014年   10篇
  2013年   21篇
  2012年   17篇
  2011年   18篇
  2010年   14篇
  2009年   7篇
  2008年   13篇
  2007年   8篇
  2006年   10篇
  2005年   6篇
  2004年   3篇
  2003年   8篇
  2002年   1篇
  2001年   4篇
  2000年   2篇
  1999年   2篇
  1998年   9篇
  1997年   4篇
  1996年   5篇
  1995年   6篇
  1994年   4篇
  1992年   6篇
  1991年   3篇
  1990年   4篇
  1989年   2篇
  1988年   2篇
  1987年   1篇
  1986年   5篇
  1985年   1篇
  1983年   1篇
  1976年   3篇
  1974年   1篇
  1971年   1篇
排序方式: 共有279条查询结果,搜索用时 15 毫秒
121.
The ability of small heat shock proteins (sHSP) at preventing the aggregation and precipitation of unfolded and misfolded proteins because of changes in pH and temperature is widely recognised. The performance of sHSP from bovine lens extract at protecting sarcoplasmic proteins from heat induced denaturation and aggregation was compared with other chaperones including bovine serum albumin, αs‐casein, β‐casein and a synthetic peptide based upon αA‐crystallin (AAC). Beef sarcoplasmic proteins were heated in the presence or absence of exogenous chaperone and the solubility, surface hydrophobicity and enzymatic activities of the sarcoplasmic proteins was determined. Lens extract prevented the aggregation of sarcoplasmic proteins, maintaining solubility and clarity up to 65 °C relative to 60 °C for β‐casein. By contrast, αs‐ and β‐casein proteins protected the activity of endogenous enzymes at temperatures between 37 °C and 52 °C, unlike lens sHSP. Our findings support the addition of casein proteins as potential thermal stabilisers of meat proteins in food systems.  相似文献   
122.
123.
Melamine resins were used as 50-μm-thick fire retardant coatings for polypropylene (PP). Preceding deposition, low-pressure plasma polymer films of allyl alcohol were coated onto PP to improve the adhesion between PP and melamine resin coatings. The efficiency of such fire retardant coatings was confirmed by flame tests. The plasma-deposited polymer and the dip-coated melamine resin films were characterized by Fourier transform infrared-attenuated total reflectance spectroscopy and X-ray photoelectron spectroscopy (XPS). The adhesion of coatings was measured using a 90° peel test with a doubled-faced adhesive tape. To detect the locus of failure, the peeled layer surfaces were inspected using optical microscopy and XPS. Thermal properties of PP thick melamine resin-coated films were analyzed by thermogravimetric analysis.  相似文献   
124.
Microscale processes offer a substantial advantage to the process industry as separation is conducted rapidly and efficiently. However, the effectiveness of the separation depends on the stability of the flow regime. Experimental and numerical analysis was carried out to characterize the flow patterns of polyethylene glycol 200 (PEG200) and diesel fuel at several flow ratios in order to achieve optimal conditions for a stable pattern. Computational fluid dynamics (CFD) was employed using the volume-of-fluid (VOF) model and the results were validated with the experimental data. Both experimental and numerical outcomes revealed two-phase flow patterns. These findings enable the application of the simulated module for further liquid-liquid mass transfer studies where sulfuric compounds exist as solutes in the fuel.  相似文献   
125.
The paper reviews product data technology initiatives in the construction sector and provides a synthesis of related ICT industry needs. A comparison between (a) the data centric characteristics of Product Data Technology (PDT) and (b) ontology with a focus on semantics, is given, highlighting the pros and cons of each approach. The paper advocates the migration from data-centric application integration to ontology-based business process support, and proposes inter-enterprise collaboration architectures and frameworks based on semantic services, underpinned by ontology-based knowledge structures. The paper discusses the main reasons behind the low industry take up of product data technology, and proposes a preliminary roadmap for the wide industry diffusion of the proposed approach. In this respect, the paper stresses the value of adopting alliance-based modes of operation.  相似文献   
126.
The Journal of Supercomputing - Maximal Clique Enumeration (MCE), which consists to enumerate all maximal complete subgraphs in a given graph, is a fundamental problem in graph theory, and it is...  相似文献   
127.
The paper explores the adoption of information and communication technology-enabled alliance modes of operation by small- and medium-sized enterprises (SMEs) in the construction sector. It argues that SME alliance modes of operations promote business process innovation and allow SMEs to compete in new ways, get better reward for their work, and gain greater financial strength, which in turn, will give them the financial capability to move forward and develop their products and services. Findings from the multiple case study approach used to conduct the research are discussed, including: (1) the concept of an SME alliance and its key features; (2) business relationships management in an SME alliance; (3) SME alliance viability and sustainability; (4) the role of information and communication technologies in an alliance; and (5) technical innovation management in an alliance regime of peers. Recommendations for future research in the form of open questions to the research community are given.  相似文献   
128.
A new model of the equations of generalized thermoviscoelasticity for a thermally, isotropic and electrically conducting half-space solid whose surface is subjected to a thermal shock is given. The formulation is applied to the generalized thermoelasticity based on the Green and Naghdi (GN) theory under the effect of rotation, where there is an initial magnetic field parallel to the plane boundary of the half-space. The medium is deformed because of thermal shock and due to the application of the magnetic field, it results in induced magnetic and electric fields in the medium. The normal mode analysis is used to obtain the expressions for the variables considered. The distributions of temperature, displacement, stress, induced magnetic and electric fields are represented graphically. Comparisons are made with the results predicted by the types II and III in the presence and absence of rotation.  相似文献   
129.
A series of borotungstate glasses was prepared. The glass formation was confirmed by using X-ray diffraction measurements on the powder samples then measured using Mo¨ssbauer, differential thermal analysis (DTA), infra-red (IR) and d.c. conductivity. The iron in the alkali borate tungstate glass was found in the ferric state only. The introduction of tungsten to replace 25 mol % sodium tetraborate in the glass samples caused a little shift in the IR bands toward the lower frequency. The iron ions may act as a glass modifier whereas the tungsten ions may act as network former. The electrical conduction increased in the presence of tungsten due to the hopping mechanism between the two sites of tungsten (W5+, W6+).  相似文献   
130.
The small-satellite thermal subsystem main function is to control temperature ranges on equipments, and payload for the orbit specified. Structure subsystem has to ensure the satellite structure integrity. Structure integrity should meet two constraints; first constraint is accepted fatigue damage due to cyclic temperature, and second one is tolerable mounting accuracy at payload and Attitude Determination and Control Subsystem (ADCS) equipments’ seats. First, thermal analysis is executed by applying finite-difference method (IDEAS) and temperature profile for satellite components case is evaluated. Then, thermal fatigue analysis is performed applying finite-element analysis (ANSYS) to calculate the resultant damage due to on-orbit cyclic stresses, and structure deformations at the payload and ADCS equipments seats.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号