全文获取类型
收费全文 | 2167篇 |
免费 | 77篇 |
国内免费 | 12篇 |
专业分类
电工技术 | 39篇 |
综合类 | 3篇 |
化学工业 | 435篇 |
金属工艺 | 51篇 |
机械仪表 | 51篇 |
建筑科学 | 42篇 |
矿业工程 | 3篇 |
能源动力 | 103篇 |
轻工业 | 117篇 |
水利工程 | 6篇 |
石油天然气 | 17篇 |
无线电 | 353篇 |
一般工业技术 | 483篇 |
冶金工业 | 298篇 |
原子能技术 | 21篇 |
自动化技术 | 234篇 |
出版年
2023年 | 20篇 |
2022年 | 44篇 |
2021年 | 68篇 |
2020年 | 51篇 |
2019年 | 43篇 |
2018年 | 82篇 |
2017年 | 67篇 |
2016年 | 59篇 |
2015年 | 37篇 |
2014年 | 79篇 |
2013年 | 151篇 |
2012年 | 100篇 |
2011年 | 101篇 |
2010年 | 68篇 |
2009年 | 80篇 |
2008年 | 81篇 |
2007年 | 93篇 |
2006年 | 69篇 |
2005年 | 45篇 |
2004年 | 49篇 |
2003年 | 49篇 |
2002年 | 55篇 |
2001年 | 34篇 |
2000年 | 32篇 |
1999年 | 42篇 |
1998年 | 98篇 |
1997年 | 61篇 |
1996年 | 53篇 |
1995年 | 51篇 |
1994年 | 39篇 |
1993年 | 32篇 |
1992年 | 32篇 |
1991年 | 27篇 |
1990年 | 29篇 |
1989年 | 17篇 |
1988年 | 26篇 |
1987年 | 10篇 |
1986年 | 13篇 |
1985年 | 13篇 |
1984年 | 14篇 |
1983年 | 16篇 |
1982年 | 11篇 |
1981年 | 12篇 |
1980年 | 6篇 |
1979年 | 16篇 |
1978年 | 14篇 |
1977年 | 8篇 |
1976年 | 20篇 |
1975年 | 6篇 |
1973年 | 11篇 |
排序方式: 共有2256条查询结果,搜索用时 9 毫秒
71.
A. Ananthanarayanan S. A. Khot V. Jaiswal A. Joseph P. P. Songire D. Banerjee 《The International journal of environmental studies》2017,74(2):192-201
Ag loaded mordenite can be used as a trap for radio-iodine arising from nuclear reprocessing operations. Typically, iodine is trapped in the Ag loaded mordenite by the formation of AgI in the pores of the mordenite, through a solid-vapour reaction. In the presence of NOx and water vapour, AgI is most likely formed by liquid-vapour reaction between AgNO3 and I2. This reaction results in the formation of large aggregates of AgI crystals on the surface of the mordenite, also leading to a yellow colouration of the mordenite, which is not observed when NOx and water vapour is absent. 相似文献
72.
Soumya Ghosh Chowdhury Jagannath Chanda Sreedip Ghosh Koushik Banerjee Shib Shankar Banerjee Amit Das Prasenjit Ghosh Sanjay Kr. Bhattacharyya Rabindra Mukhopadhyay 《Polymer Engineering and Science》2020,60(8):1973-1983
Proficiency on underlying mechanism of rubber-metal adhesion has been increased significantly in the last few decades. Researchers have investigated the effect of various ingredients, such as hexamethoxymethyl melamine, resorcinol, cobalt stearate, and silica, on rubber-metal interface. The role of each ingredient on rubber-metal interfacial adhesion is still a subject of scrutiny. In this article, a typical belt skim compound of truck radial tire is selected and the effect of each adhesive ingredient on adhesion strength is explored. Out of these ingredients, the effect of cobalt stearate is found noteworthy. It has improved adhesion strength by 12% (without aging) and by 11% (humid-aged), respectively, over control compound. For detailed understanding of the effect of cobalt stearate on adhesion, scanning electron microscopy and energy dispersive spectroscopy are utilized to ascertain the rubber coverage and distribution of elements. X-ray photoelectron spectroscopy results helped us to understand the impact of CuXS layer depth on rubber-metal adhesion. The depth profile of the CuXS layer was found to be one of the dominant factors of rubber-metal adhesion retention. Thus, this study has made an attempt to find the impact of different adhesive ingredients on the formation of CuXS layer depth at rubber-metal interface and establish a correlation with adhesion strength simultaneously. 相似文献
73.
Shruti Deshmukh Stephen Burbine Erin Keaney Shib Shankar Banerjee Artee Panwar Christopher Peters Mary Herndon Derrick Rockosi Joey Mead Carol Barry 《Polymer Engineering and Science》2020,60(11):2782-2792
Highly-filled polymer systems include color masterbatches, feedstocks for powder injection molding, and rigid sheets with high levels of flame retardants, but they have not been explored for flexible sheet. This work investigated the (a) selecting a polymer matrix with enough melt strength and flexibility to form a stable sheet with high filler loading, (b) the maximum achievable filler loading for the sheet, and (c) optimizing the process of extruding a highly-filled flexible polymer system. Extrusion grade low-density polyethylene (LDPE) provided sufficient flexibility and permitted a maximum filler loading of 36 vol% (~78 wt%). Good dispersion of the nanoparticle filler, however, required two passes through multiple screw extruders and a small reduction in the viscosity of the LDPE. Sheet with thickness of 415 μm, surface roughness of <1 μm, and sufficient flexibility was extruded continuously at a rate of 10 m/min., but it required a more traditional coat hanger manifold to prevent filler hang up in the sheet die. The filler particles were distributed uniformly through the core and skin of the sheet, giving the sheet good mechanical properties. 相似文献
74.
75.
Wireless Personal Communications - As a result of the rapid progress in editing techniques, fakes and forgeries in images became easy and pervasive. Image forgery detection methods have been... 相似文献
76.
77.
78.
79.
Soy whey is generated as a process waste while preparing soy based food products tofu, causing environmental pollution and also representing an economic penalty against the industrial process. Therefore, its valorization is of prime importance to the industry. The present investigation aims to convert this proteinaceous waste into bioactive peptide enriched hydrolysate. Soy whey protein was enzymatically treated with the Aspergillus awamori nakazawa protease. Respective protease was efficient to produce antioxidant peptide beholding radical scavenging ability of 40–50% at normal conditions. Remarkable increase in the radical scavenging activity upto 70% was noticed at the response surface methodology (RSM) based optimized condition: temperature 40°C, salt concentration (NaCl) 0.05 M, surfactant concentration (Triton-X 100) 0.0075%, hydrolysis time 80 min, and enzyme to substrate concentration 164 IU/g of soy whey protein. The present study emphasizes the biotransformation of proteineceous waste into antioxidant peptide rich soy whey protein hydrolysate to be considered as additives for food preparation and formulation. 相似文献
80.
Ann Barrett Anuradha Prakash Deborah Sakelakos Irwin Taub Samuel Cohen Yuki Ohashi 《Food Hydrocolloids》1998,12(4):401-408
The effects of composition and thermal treatment on the water sorption and diffusional properties of idealized protein gels arranged in bilayer configurations were determined; these water binding/migration properties were related to the mechanical characteristics of the gels. Samples were prepared from whey protein concentrate (WPC), they consisted of water:WPC ratios of 1.5 to 5.67, and were thermally set for 20–60 min. Moisture migration rates from samples interfaced with filters were determined, as were moisture sorption capacities of samples immersed in water. The physical properties of the gels were assessed by uniaxial compression and microscopy. Results showed that gel strength and consequent extent of protein interaction—as affected by thermal treatment—controlled the ability of the gel structure to absorb water. Sorption was exponentially correlated with gel modulus and linearly correlated with a function of protein content, heating time, and immersion time. Rates of diffusion from interfaced gels were dependent solely on water content. It was concluded that the degree of protein interaction, whether influenced by concentration or thermal treatment, affected network extensibility and thus the capacity of the gels to act as receptors of moisture. Results have implications for the functionality of shelf-stable sandwiches and other multicomponent foods. 相似文献