全文获取类型
收费全文 | 1534篇 |
免费 | 22篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 13篇 |
化学工业 | 254篇 |
金属工艺 | 90篇 |
机械仪表 | 59篇 |
建筑科学 | 27篇 |
矿业工程 | 35篇 |
能源动力 | 19篇 |
轻工业 | 122篇 |
水利工程 | 90篇 |
石油天然气 | 230篇 |
无线电 | 60篇 |
一般工业技术 | 300篇 |
冶金工业 | 96篇 |
原子能技术 | 33篇 |
自动化技术 | 129篇 |
出版年
2018年 | 14篇 |
2017年 | 20篇 |
2016年 | 27篇 |
2013年 | 146篇 |
2012年 | 41篇 |
2011年 | 49篇 |
2010年 | 30篇 |
2009年 | 15篇 |
2008年 | 22篇 |
2007年 | 14篇 |
2006年 | 15篇 |
2003年 | 13篇 |
2002年 | 13篇 |
2001年 | 19篇 |
2000年 | 21篇 |
1999年 | 20篇 |
1998年 | 28篇 |
1997年 | 22篇 |
1994年 | 15篇 |
1993年 | 23篇 |
1992年 | 17篇 |
1991年 | 34篇 |
1990年 | 28篇 |
1989年 | 28篇 |
1988年 | 29篇 |
1987年 | 25篇 |
1986年 | 19篇 |
1985年 | 27篇 |
1984年 | 38篇 |
1983年 | 14篇 |
1982年 | 20篇 |
1981年 | 28篇 |
1980年 | 35篇 |
1979年 | 36篇 |
1978年 | 44篇 |
1977年 | 41篇 |
1976年 | 35篇 |
1975年 | 47篇 |
1974年 | 50篇 |
1973年 | 38篇 |
1972年 | 28篇 |
1971年 | 28篇 |
1970年 | 34篇 |
1969年 | 29篇 |
1968年 | 23篇 |
1967年 | 20篇 |
1966年 | 17篇 |
1965年 | 19篇 |
1964年 | 14篇 |
1963年 | 12篇 |
排序方式: 共有1557条查询结果,搜索用时 0 毫秒
1.
2.
The article established the regularities of change of the physicomechanical characteristics and strength of glass textolites in single and repeated thermal loading. It shows that under multiple loading the intense loss of strength of the investigated materials is due to increased porosity on account of the large number of microcracks appearing in the structure. A correlation is obtained between the elastic and strength characteristics and porosity in dependence on the temperature of multiple heating which in the first approximation is described by a polynomial of second degree with respect to temperature, multiplied by the reciprocal of porosity.Translated from Problemy Prochnosti, No. 6, pp. 53–58, June, 1991. 相似文献
3.
Ér. V. Kal’yanov 《Technical Physics Letters》2007,33(6):451-453
A new simple model of a system with chaotic dynamics, based on the equations of bistable systems, is considered. The possibility of converting harmonic signals into chaotic oscillations, which represent intermittent irregular and switching quasi-regular motions, is demonstrated by numerical methods. The mechanism of chaotization is analyzed using the results of numerical calculations. 相似文献
4.
Patrick DAstous Franoise Dtienne Willemien Visser Pierre N. Robillard 《Design Studies》2004,25(6):625-655
By contrast to design meetings, design evaluation meetings (DEMs) have generally been considered as situations in which, according to DEM methodologies, design activities are quite marginal. In a study of DEMs in software development, i.e. in technical review meetings following a particular review methodology, we showed: (i) the occurrence of design activities as part of an argumentation process; (ii) the relative importance of cognitive synchronisation as a prerequisite for evaluation; (iii) the important role played in evaluation by argumentation that makes explicit the underlying design rationale (DR). On the basis of our results, we discuss the potential for using DR methodologies in this kind of meetings. 相似文献
5.
6.
The properties of glasses of the lithium-aluminoborosilicate system were investigated, namely, the density, spreadability, thermal expansion, and nature of crystallized phases at various temperatures. A crystal-optical analysis was conducted. The glasses were used to prepare abrasive compositions. Their strength properties were studied as a function of the composition of the glass binder and the regime of heat treatment.Translated from Steklo i Keramika, No. 3, pp. 27–30, March, 1996. 相似文献
7.
The fluctuations observed by recording the picosecond pulses of a mode-locked laser with a synchroscan streak camera are due to the laser jitter and to the variations of the zero crossing of the synchronization. By means of a simple model, it is shown that the dispersions measured when the synchronization is generated from the mode-locker oscillator reflect the instantaneous time phase fluctuations of this oscillator. From the study of the experimental recordings with methods of time series analysis it results that the phase noise of the electronic oscillator is consistent with an underlying low-dimensional strange attractor. 相似文献
8.
Éntin S. V. Anzheurov N. M. Krasovitskii Yu. V. Panova O. A. Shcheglova L. I. 《Refractories and Industrial Ceramics》2003,44(3):194-198
An experimental setup for studying filter-assisted dust collection is described. The role of various factors — hydraulic resistance, filtering velocity, dust concentration, pressure drop, efficiency of recovery — in the performance of filters intended for use in the production of refractory materials is considered. The dust removal method was tested under industrial conditions at the Semilukskii Refractory Plant and can be recommended for wider use in different branches of industry. 相似文献
9.
A new gauge configuration for the measurement of outside dimensions up to 70 mm is described. The main advantage of the instrument is that it can be used to perform absolute measurements, i.e., without adjustment operations. The instrument has potential applications in many industries engaged in the manufacture of parts in relatively small lots.Translated from Izmeritel'naya Tekhnika, No. 10, pp. 32–33, October, 1993. 相似文献
10.
Diffusion chromizing and boriding of iron-base powder materials SP30, SP90, and SP90D3 are studied. The growth kinetics for diffusion layers are determined depending on diffusion impregnation conditions, and material composition and porosity. Comparative bending and tensile strength tests as well as wear- and heat-resistance tests for materials after sintering by standard conditions or boriding and chromizing are performed. It is shown that the mechanical properties of materials after different types of processing are approximately the same whereas the wear and heat resistance after diffusion impregnation increase markedly. This makes it possible to conclude that a combination of sintering and boriding (or chromizing) is possible under the following conditions: boriding at 1000°C for 2–3 h; chromizing at 1100°C for 3–4 h.Kiev Polytechnic Institute. Translated from Poroshkovaya Metallurgiya, No. 8(368), pp. 37–43, August, 1993. 相似文献