全文获取类型
收费全文 | 1562篇 |
免费 | 25篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 13篇 |
化学工业 | 260篇 |
金属工艺 | 93篇 |
机械仪表 | 59篇 |
建筑科学 | 29篇 |
矿业工程 | 35篇 |
能源动力 | 17篇 |
轻工业 | 126篇 |
水利工程 | 90篇 |
石油天然气 | 230篇 |
无线电 | 73篇 |
一般工业技术 | 304篇 |
冶金工业 | 101篇 |
原子能技术 | 36篇 |
自动化技术 | 122篇 |
出版年
2018年 | 14篇 |
2017年 | 22篇 |
2016年 | 24篇 |
2013年 | 150篇 |
2012年 | 44篇 |
2011年 | 50篇 |
2010年 | 32篇 |
2009年 | 16篇 |
2008年 | 23篇 |
2007年 | 17篇 |
2006年 | 15篇 |
2003年 | 15篇 |
2002年 | 13篇 |
2001年 | 19篇 |
2000年 | 19篇 |
1999年 | 19篇 |
1998年 | 30篇 |
1997年 | 25篇 |
1994年 | 16篇 |
1993年 | 27篇 |
1992年 | 17篇 |
1991年 | 35篇 |
1990年 | 28篇 |
1989年 | 29篇 |
1988年 | 30篇 |
1987年 | 25篇 |
1986年 | 18篇 |
1985年 | 27篇 |
1984年 | 38篇 |
1983年 | 13篇 |
1982年 | 19篇 |
1981年 | 29篇 |
1980年 | 34篇 |
1979年 | 37篇 |
1978年 | 45篇 |
1977年 | 41篇 |
1976年 | 35篇 |
1975年 | 47篇 |
1974年 | 51篇 |
1973年 | 39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1588条查询结果,搜索用时 15 毫秒
1.
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
2.
3.
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
4.
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
5.
A multiconfiguration Dirac-Fock (MCDF) technique has been used for computing the wavelengths and transition probabilities for lines in the X-ray spectra of the gallium-like ions from Yb XL to U LXII. Results are presented for the 4s24p-4s24d and 4s24p-4s4p2 allowed transitions (E1) as well as for the forbidden transitions (M1 and E2) within the ground configuration 4s24p. A comparison of the calculated wavelengths with the few experimental results available is also presented. 相似文献
6.
Computer aided design of microwave monolithic integrated circuits must combine two different fields. The first domain is the simulation of microwave circuits taking into account non linear aspects development of time domain and harmonic balance simulation algorithms specialized for microwave circuits. In the second place are found, the layout algorithms which were developed for logic circuits (on Si or GaAs). The association of these two types of algorithms leads to the constitution of aCad workstation for microwave monolithic integrated circuits. Two examples of design and realization of integrated circuits with these tools are presented. 相似文献
7.
8.
9.
10.
MEXICA is a computer model that produces frameworks for short stories based on the engagement-reflection cognitive account of writing. During engagement MEXICA generates material guided by content and rhetorical constraints, avoiding the use of explicit goals or story-structure information. During reflection the system breaks impasses, evaluates the novelty and interestingness of the story in progress and verifies that coherence requirements are satisfied. In this way, MEXICA complements and extends those models of computerised story-telling based on traditional problem-solving techniques where explicit goals drive the generation of stories. This paper describes the engagement-reflection account of writing, the general characteristics of MEXICA and reports an evaluation of the program. 相似文献