全文获取类型
收费全文 | 991篇 |
免费 | 23篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 18篇 |
综合类 | 1篇 |
化学工业 | 236篇 |
金属工艺 | 26篇 |
机械仪表 | 23篇 |
建筑科学 | 32篇 |
能源动力 | 39篇 |
轻工业 | 59篇 |
水利工程 | 3篇 |
石油天然气 | 1篇 |
无线电 | 130篇 |
一般工业技术 | 204篇 |
冶金工业 | 88篇 |
原子能技术 | 3篇 |
自动化技术 | 153篇 |
出版年
2022年 | 19篇 |
2021年 | 34篇 |
2020年 | 25篇 |
2019年 | 23篇 |
2018年 | 28篇 |
2017年 | 25篇 |
2016年 | 15篇 |
2015年 | 15篇 |
2014年 | 23篇 |
2013年 | 76篇 |
2012年 | 42篇 |
2011年 | 45篇 |
2010年 | 45篇 |
2009年 | 38篇 |
2008年 | 54篇 |
2007年 | 34篇 |
2006年 | 28篇 |
2005年 | 31篇 |
2004年 | 26篇 |
2003年 | 16篇 |
2002年 | 18篇 |
2000年 | 6篇 |
1999年 | 11篇 |
1998年 | 28篇 |
1997年 | 21篇 |
1996年 | 13篇 |
1995年 | 12篇 |
1994年 | 10篇 |
1993年 | 8篇 |
1992年 | 9篇 |
1991年 | 12篇 |
1990年 | 14篇 |
1989年 | 8篇 |
1988年 | 16篇 |
1987年 | 8篇 |
1986年 | 7篇 |
1985年 | 6篇 |
1984年 | 15篇 |
1983年 | 14篇 |
1982年 | 11篇 |
1981年 | 7篇 |
1980年 | 11篇 |
1979年 | 12篇 |
1978年 | 8篇 |
1977年 | 6篇 |
1976年 | 19篇 |
1975年 | 12篇 |
1974年 | 8篇 |
1973年 | 6篇 |
1971年 | 8篇 |
排序方式: 共有1016条查询结果,搜索用时 15 毫秒
91.
Thazhakot V Sankar Alappat Ramachandran 《Journal of the science of food and agriculture》2002,82(9):1021-1027
The gel strength, compressibility and folding characteristic of suwari (set) and kamaboko (set and cooked) gels prepared from rohu ( Labeo rohita ), catla ( Catla catla ) and mrigal ( Cirrhinus mrigala ) surimi were examined to understand the occurrence of suwari and modori phenomena in surimi from major freshwater carps. Suwari setting of gels did not take place at lower temperatures. Suwari gels showed good gel strength at 50 °C for rohu and at 60 °C for catla and mrigal after 30 min setting time. Incubation for 60 min decreased the gel strength at 60 °C for rohu and catla. Setting at 25 °C followed by cooking at 90 °C increased the gel strength. Increased setting temperature, however, decreased the gel strength of cooked gels. Gel strength and compressibility data were supported by folding characteristics. © 2002 Society of Chemical Industry 相似文献
92.
G. Balakrishnan P. Kuppusami S. Murugesan Chanchal Ghosh Divakar Ramachandran E. Mohandas D. Sastikumar 《Transactions of the Indian Institute of Metals》2011,64(3):297-299
Multilayers of CeO2/ZrO2 thin films were deposited on Si (100) substrates using pulsed laser deposition at an optimized oxygen partial pressure of
3×10−2 mbar and at room temperature. The CeO2 layer thickness was 10 nm, while the ZrO2 layer thickness was varied as 10, 20 and 30 nm. CeO2 and ZrO2 layers were deposited alternately to obtain 25 bilayers. High temperature x-ray diffraction (HTXRD) results showed that the
multilayer films had cubic ceria and tetragonal ZrO2. Thermal expansion coefficients were calculated for CeO2 and t-ZrO2 and found to increase with the decrease of ZrO2 layer thickness. The cross sectional transmission electron microscopy (XTEM) of CeO2/ZrO2 multilayer also indicated that ceria was found to be in cubic phase while zirconia contained predominantly tetragonal phase
along with cubic phase in thermally annealed specimen. 相似文献
93.
Seyyed Reza Pishva Ramachandran Vasudevan Ali Etemad Farzad Heidari Makanko Komara Patimah Ismail Fauziah Othman Abdollah Karimi Mohammad Reza Sabri 《International journal of molecular sciences》2013,14(2):2739-2752
Ventricular septal defect (VSD) is one of the most common types of congenital heart defects (CHD). There are vivid multifactorial causes for VSD in which both genetic and environmental risk factors are consequential in the development of CHD. Methionine synthase reductase (MTRR) and methylenetetrahydrofolate reductase (MTHFR) are two of the key regulatory enzymes involved in the metabolic pathway of homocysteine. Genes involved in homocysteine/folate metabolism may play an important role in CHDs. In this study; we determined the association of A66G and C524T polymorphisms of the MTRR gene and C677T polymorphism of the MTHFR gene in Iranian VSD subjects. A total of 123 children with VSDs and 125 healthy children were included in this study. Genomic DNA was extracted from the buccal cells of all the subjects. The restriction fragment length polymorphism polymerase chain reaction (PCR-RFLP) method was carried out to amplify the A66G and C524T polymorphism of MTRR and C677T polymorphism of MTHFR genes digested with Hinf1, Xho1 and Nde1 enzymes, respectively. The genotype frequencies of CC, CT and TT of MTRR gene among the studied cases were 43.1%, 40.7% and 16.3%, respectively, compared to 52.8%, 43.2% and 4.0%, respectively among the controls. For the MTRR A66G gene polymorphism, the genotypes frequencies of AA, AG and GG among the cases were 33.3%, 43.9% and 22.8%, respectively, while the frequencies were 49.6%, 42.4% and 8.0%, respectively, among control subjects. The frequencies for CC and CT genotypes of the MTHFR gene were 51.2% and 48.8%, respectively, in VSD patients compared to 56.8% and 43.2% respectively, in control subjects. Apart from MTHFR C677T polymorphism, significant differences were noticed (p < 0.05) in C524T and A66G polymorphisms of the MTRR gene between cases and control subjects. 相似文献
94.
95.
96.
The widespread applications of polymeric materials require the use of conventional flame retardants based on halogen and phosphorous compounds to satisfy fire safety regulatory standards. However, these compounds, particularly halogen-based examples, are persistent organic pollutants of global concern and generate corrosive/toxic combustion products. To account for eco-friendliness, ultimate mechanical/physical properties and processing difficulties, the window of options has become too narrow. Although the incorporation of non-toxic nanofillers in polymers shows positive potential towards flame retardancy, many obstacles remain. Moreover, most of the literature on these materials is qualitative, and often points to conflicting/misleading suggestions from the perspectives of short-term and long-term fire exposure tests. Hence, there is a renewed need to fundamentally understand the fire response of such materials, and complement experimental results with theoretical modelling and/or numerical simulation. 相似文献
97.
This paper discusses the iterative provision of modelling insights on long-term decarbonisation scenarios for UK energy policy makers. A multi-year model construction process of the UK MARKAL-Macro-hybrid energy-economic model, and four subsequent major policy analyses illustrates the scope of this interaction. The initial set of modelling runs focused on the technical feasibility of long-term 60% carbon dioxide (CO2) reduction scenarios, the role of key technologies, and the underlying uncertainties. Furthermore subsequent modelling studies were aimed to generate insights on more stringent targets, and on issues and uncertainties that may make targets harder to achieve. Hence, this paper analyses the large number of long-term UK CO2 reduction scenarios through a clustering approach on target stringency and barriers to implementation. Robust findings and key uncertainties are highlighted, including the critical role of the power sector, trade-offs between resources, sectors, key energy technologies and behavioural responses, and the increasing level and spread of CO2 marginal prices and GDP impacts. The relevance and use of modelling insights to the UK energy policy process is shown in the continuation of the energy modelling–policy interface. This constitutes both ongoing model development, and nuanced scenario analysis designed to further explore key uncertainties in evolving policy issues. 相似文献
98.
Sarkar Santonu Ramachandran Shubha Kumar G. Sathish Iyengar Madhu K. Rangarajan K. Sivagnanam Saravanan 《Software, IEEE》2009,26(2):28-35
Large software systems, developed over several years, are the backbone of industries such as banking, retail, transportation, and telecommunications. With multiple bug fixes and feature enhancements, these systems gradually deviate from the intended architecture and deteriorate into unmanageable monoliths. This article presents a case study of a banking application besot with such problems and the modularization approach that the company adopted as a solution. It also highlights benefits unearthed as a result of this reengineering exercise. 相似文献
99.
100.