全文获取类型
收费全文 | 893篇 |
免费 | 2篇 |
国内免费 | 1篇 |
学科分类
工业技术 | 896篇 |
出版年
2022年 | 10篇 |
2021年 | 11篇 |
2018年 | 20篇 |
2017年 | 14篇 |
2016年 | 19篇 |
2014年 | 18篇 |
2013年 | 29篇 |
2012年 | 15篇 |
2011年 | 20篇 |
2010年 | 18篇 |
2009年 | 17篇 |
2008年 | 16篇 |
2007年 | 18篇 |
2006年 | 16篇 |
2005年 | 13篇 |
2004年 | 17篇 |
2003年 | 14篇 |
2002年 | 14篇 |
2001年 | 17篇 |
2000年 | 20篇 |
1999年 | 13篇 |
1998年 | 14篇 |
1997年 | 20篇 |
1991年 | 9篇 |
1990年 | 14篇 |
1989年 | 16篇 |
1987年 | 11篇 |
1986年 | 12篇 |
1985年 | 20篇 |
1984年 | 20篇 |
1983年 | 23篇 |
1982年 | 16篇 |
1981年 | 18篇 |
1980年 | 15篇 |
1979年 | 12篇 |
1978年 | 10篇 |
1977年 | 22篇 |
1976年 | 17篇 |
1975年 | 12篇 |
1974年 | 22篇 |
1973年 | 18篇 |
1971年 | 13篇 |
1970年 | 24篇 |
1969年 | 11篇 |
1966年 | 10篇 |
1965年 | 10篇 |
1964年 | 15篇 |
1963年 | 9篇 |
1960年 | 13篇 |
1959年 | 9篇 |
排序方式: 共有896条查询结果,搜索用时 15 毫秒
1.
The microstructures of Cu films deposited by the self-ion assisted, partially ionized beam (PIB) deposition technique under
two different accelerating potentials, 0 KeV and 6 KeV, are compared. The 6 KeV film shows a bimodal (111) fiber and (100)
fiber texture with an abundance of twin boundaries and a relatively large average grain size with a typical lognormal distribution.
The 0 KeV film consists of small, mostly (111) oriented grains with islands of abnormally large (100) grains. The controlling
factors for the abnormal growth of the (100) grains are discussed in relation to the observed microstructures, showing that
all factors necessary for abnormal (100) growth are present in the films. 相似文献
2.
3.
4.
In this paper, we study a class of optimization problems,which are of certain interest for control theory. These problemsare of global constrained optimization and may be nonconvex ingeneral. A simple approach to their solution is presented. Aspecial attention is paid to the case when the objective andconstraints functions are quadratic functionals on a Hilbertspace. As an example of an application of the general approach,a methodology is presented by which an optimal controller canbe synthesized for a finite-horizon linear-quadratic controlproblem with quadratic constraints. Both inequality and equalityconstraints are considered. The objective and constraints functionalsmay be nonconvex and may contain both integral and terminal summands.It is shown that, under certain assumptions, the optimal controlexists, is unique, and has feedback structure. Furthermore, theoptimal controller can be computed by the methods of classiclinear-quadratic control theory coupled with those of finitedimensional convex programming. 相似文献
5.
Conclusions It has been found experimentally that to increase the uniformity of linear density of yarn spun from an aggressive spinning solution of 40–50 Pa·sec viscosity, it is necessary to use metering pumps of high output and to maintain a positive pressure difference of up to 1 MPa between the spinning solution pressure at intake and that at discharge from the pump.A new candle filter construction has been proposed for maintaining a positive difference between the spinning solution pressure at intake and at discharge.Translated from Khimicheskie Volokna, No. 1, pp. 40–41, January–February, 1986. 相似文献
6.
Evidence for biotic control of Australian reservoir phytoplankton communities and the potential for applied biomanipulation 总被引:1,自引:0,他引:1
Vladimir Matveev 《Lakes & Reservoirs: Research and Management》1998,3(2):105-111
Although some concerns have been expressed with respect to the applicability of biomanipulation to Australian reservoirs and other inland waters, no major obstacles were found in this review. The previous doubts stimulated research, which has provided evidence for unexpected mechanisms of food web interactions, such as positive effects of small copepods on planktonic algae, higher than usual grazing potential of cladoceran communities, and direct positive effects of planktivores on phytoplankton. Further research into zooplankton-cyanobacteria interactions should indicate how widespread is the previously reported ability of some southern hemisphere crustaceans to benefit at a population level from feeding on cyanobacteria. Quantitative fisheries acoustics, which has not been widely used in biomanipulation trials before, is a promising new tool in the assessment of the biomass of planktivorous fish in the pelagic zone of reservoirs. 相似文献
7.
8.
A. V. Shilov P. V. Matveev T. A. Feoktistova K. A. Polyakov A. E. Polyakov 《Fibre Chemistry》2007,39(3):245-246
An automatic control system for spinning and winding of synthetic fibres that provides for operation of the electric drive
of the metering pumps in conditions of stabilization of the melt pressure and rotation rate of the winder drive was proposed.
A laboratory bench that simulates operation of the device for controlling spinning and winding of synthetic fibres based on
software provided in a microcomputer was created. A parametric, adjustable, asynchronous electric drive from the KPE series
which provides for energy-saving conditions was used for the extruder drive.
__________
Translated from Khimicheskie Volokna, No. 3, pp. 56–57, May–June, 2007. 相似文献
9.
10.
V. S. Matveev G. A. Budnitskii G. P. Mashinskaya L. B. Aleksandrova N. M. Sklyarov 《Fibre Chemistry》1997,29(6):381-384
The following conclusions can be drawn from an analysis of the data reported in the present article: SVM and Armos fibres
are now the most promising for use in bulletproof materials; increasing the elongation to 5–6% while preserving the strength
at the level of 400–450 kgf/mm
2
allows increasing the efficiency of use of fibres for bulletproofing; the method proposed here allows rapidly and efficiently
conducting comparative tests and initial selection of materials and the pack structure of the energy-absorbing polymer support;
new types of bulletproof fabrics must be developed to increase the efficiency of manifestation of the energy-absorbing properties
of fibres.
Translated from Khimicheskie Volokna, No. 6, pp. 37–40, November–December, 1997. 相似文献