全文获取类型
收费全文 | 768篇 |
免费 | 6篇 |
专业分类
电工技术 | 2篇 |
化学工业 | 112篇 |
金属工艺 | 28篇 |
机械仪表 | 22篇 |
建筑科学 | 11篇 |
矿业工程 | 16篇 |
能源动力 | 3篇 |
轻工业 | 3篇 |
水利工程 | 26篇 |
石油天然气 | 113篇 |
无线电 | 36篇 |
一般工业技术 | 160篇 |
冶金工业 | 166篇 |
原子能技术 | 52篇 |
自动化技术 | 24篇 |
出版年
2022年 | 13篇 |
2019年 | 7篇 |
2018年 | 20篇 |
2017年 | 23篇 |
2016年 | 31篇 |
2015年 | 8篇 |
2014年 | 11篇 |
2013年 | 27篇 |
2012年 | 21篇 |
2011年 | 20篇 |
2010年 | 14篇 |
2009年 | 17篇 |
2008年 | 15篇 |
2007年 | 27篇 |
2006年 | 18篇 |
2005年 | 21篇 |
2004年 | 14篇 |
2003年 | 11篇 |
2002年 | 13篇 |
2000年 | 16篇 |
1999年 | 7篇 |
1998年 | 18篇 |
1997年 | 16篇 |
1996年 | 11篇 |
1995年 | 11篇 |
1993年 | 10篇 |
1992年 | 17篇 |
1991年 | 8篇 |
1990年 | 8篇 |
1989年 | 9篇 |
1988年 | 11篇 |
1987年 | 12篇 |
1986年 | 11篇 |
1985年 | 9篇 |
1984年 | 18篇 |
1983年 | 11篇 |
1982年 | 10篇 |
1981年 | 18篇 |
1980年 | 12篇 |
1979年 | 14篇 |
1978年 | 13篇 |
1977年 | 9篇 |
1976年 | 24篇 |
1975年 | 11篇 |
1974年 | 14篇 |
1973年 | 18篇 |
1972年 | 13篇 |
1971年 | 16篇 |
1969年 | 7篇 |
1967年 | 7篇 |
排序方式: 共有774条查询结果,搜索用时 15 毫秒
1.
2.
N. A. Sivov A. I. Martynenko G. N. Bondarenko M. P. Filatova E. Yu. Kabanova N. I. Popova A. N. Sivov E. B. Kruts’ko 《Petroleum Chemistry》2006,46(1):41-59
Structures and compositions of the monomers guanidine acrylate and guanidine methacrylate, their homopolymers, and copolymers with diallyldimethylammonium chloride enriched in acrylate comonomer units were determined. It was shown that ampholytic copolymers, owing to their ionic nature, contained comonomeric guanidine acrylate or methacrylate units and diallyldimethylammonium chloride units, as well as the acrylate comonomer with the diallyl counterion and polymeric acrylate and diallyl ion pairs. It follows from IR and 1H NMR data that guanidine methacrylate has the same structure (with two hydrogen bonds) in the solid state and in solutions. Guanidine acrylate structures in the solid state and in dimethylsulfoxide are identical and analogous to guanidine methacrylate structure in this solvent. In water, the guanidine acrylate structure has another type of hydrogen bonding (with one hydrogen bond, where the proton is shifted toward the guanidine group). These features of hydrogen bonding of guanidine acrylate and guanidine methacrylate are also retained in their homopolymers and copolymers with diallyldimethylammonium chloride. It was shown that the thermal stability of the copolymers was higher than that of their homopolymers, confirming the formation of intramolecular ion pairs of oppositely charged units of ampholytic copolymers. Moreover, the thermal stability of guanidine methacrylate-diallyldimethylammonium chloride copolymers is higher than that of guanidine acrylate-diallyldimethylammonium chloride copolymers. 相似文献
3.
V. V. Mamutin O. V. Bondarenko A. P. Vasil’ev A. G. Gladyshev A. Yu. Egorov N. V. Kryzhanovskaya V. S. Mikhrin V. M. Ustinov 《Technical Physics Letters》2007,33(5):384-387
The optical properties of heterostructures comprising InAs/InGaAsN quantum wells in strain-compensated GaAsN/InGaAsN superlattices have been studied. It is demonstrated that, using such superlattices of various design and thickness and with additional InAs monolayer spacers, it is possible to control the wavelength of room-temperature emission from InGaAsN quantum wells within 1.3–1.6 μm without deteriorating the output radiation characteristics, which opens additional prospects for the development of lasers on GaAs substrates for telecommunication applications. 相似文献
4.
N. F. Bondarenko E. Z. Gak M. Z. Gak 《Journal of Engineering Physics and Thermophysics》2002,75(5):1234-1247
This paper gives an overview of the experimental results obtained by the method of MHD modeling in thin electrolyte layers and used to solve problems connected with the appearance of monotonic and vibrational instabilities. Primary consideration is given to the generation and interaction of transient vortex processes. As examples, the results of the investigations of flows in systems of two, three, and four vortices and periodic vortex structures, as well as of flows in the presence of obstacles of different permittivity modeling plants or technogenic screening devices intended to protect objects against pollution are presented. We consider the ways of using the results obtained in studying natural phenomena and in solving engineering-technical problems connected with mass and heat transfer and electrotransmission. 相似文献
5.
D. M. Karpinos L. R. Vishnyakov V. P. Moroz T. N. Bondarenko V. P. Dzeganovskii 《Powder Metallurgy and Metal Ceramics》1987,26(12):983-987
Conclusions Composite materials based on the thermodynamically unstable systems Zr-Mo and Zr-W have satisfactory kinetic stability of the structure up to 1373°K. At higher temperatures there occurs intense interaction between fibers and matrix entailingthe formation of solid solutions and intermetallic phases. The course of the diffusion processes in the investigated CM is determined by the history of their components, and this makes it possible to a certain extent to control these processes by corresponding preliminary thermomechanical treatment of the components.Translated from Poroshkovaya Metallurgiya, No. 12(300), pp. 40–44, December, 1987. 相似文献
6.
7.
I. A. Afanas’ev M. V. Kostina E. V. Blinov I. O. Bannykh Yu. A. Bondarenko 《Russian Metallurgy (Metally)》2007,(3):209-213
The structure and properties of an austenitic high-nitrogen corrosion-resistant 05Kh22AG15N8M2F cast steel produced by high-gradient directional solidification (HGDS) and equiaxed-grain solidification (ES) have been studied and compared. In contrast to ES, HGDS allows one to substantially decrease the degree of dendritic segregation of alloying elements, to eliminate porosity, and to increase the strength and plasticity of the steel. 相似文献
8.
9.
V. A. Bondarenko R. A. Petrosov M. A. Tanatar V. S. Yefanov V. M. Ogenko N. D. Kushch E. B. Yagubskii 《Synthetic Metals》1995,70(1-3):955-956
Temperature dependences of resistance and in plane thermopower were studied for the ET2Cu[N(CN)2]Cl1−xBrx salts for the compositions showing metallic and superconducting properties at ambient pressure (0.5 ≤ × ≤ 1). Complex relations between a character of these dependences and sample compositions were established. 相似文献
10.
Conclusions The bend strength of VNS20 and VNS32 composites is determined by the quantity of 1phase and depends little upon the content of binder (PKhl8N15 steel). The hardness, on the other hand, depends substantially upon both the 1-phase content and upon the quantity of binder.The VNS20 and VNS32 composites sintered at the temperatures of the start of formation of the liquid phase in the tungsten carbide—PKhl8N15 steel system, when compaction is completed and the rate of formation of 1-phase is still insignificant, have the optimum properties.With a satisfactory level of physicomechanical properties, the VNS20 and VNS32 composites show high corrosion resistance in a medium of nitrine with additions of nitric acid.An increase in the strength of VNS type composites may be obtained by reducing the diffusion reaction of tungsten carbide with stainless steel.Translated from Poroshkovaya Metallurgiya, No. 5(281), pp. 69–75, May, 1986. 相似文献