全文获取类型
收费全文 | 931篇 |
免费 | 19篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 6篇 |
化学工业 | 206篇 |
金属工艺 | 52篇 |
机械仪表 | 31篇 |
建筑科学 | 6篇 |
能源动力 | 33篇 |
轻工业 | 47篇 |
水利工程 | 7篇 |
石油天然气 | 3篇 |
无线电 | 70篇 |
一般工业技术 | 266篇 |
冶金工业 | 82篇 |
原子能技术 | 15篇 |
自动化技术 | 128篇 |
出版年
2023年 | 5篇 |
2022年 | 16篇 |
2021年 | 25篇 |
2020年 | 13篇 |
2019年 | 17篇 |
2018年 | 19篇 |
2017年 | 20篇 |
2016年 | 19篇 |
2015年 | 17篇 |
2014年 | 22篇 |
2013年 | 64篇 |
2012年 | 43篇 |
2011年 | 69篇 |
2010年 | 54篇 |
2009年 | 50篇 |
2008年 | 49篇 |
2007年 | 47篇 |
2006年 | 28篇 |
2005年 | 27篇 |
2004年 | 20篇 |
2003年 | 17篇 |
2002年 | 21篇 |
2001年 | 17篇 |
2000年 | 26篇 |
1999年 | 25篇 |
1998年 | 23篇 |
1997年 | 16篇 |
1996年 | 18篇 |
1995年 | 12篇 |
1994年 | 9篇 |
1993年 | 9篇 |
1992年 | 10篇 |
1991年 | 6篇 |
1990年 | 4篇 |
1989年 | 9篇 |
1988年 | 8篇 |
1987年 | 6篇 |
1986年 | 7篇 |
1985年 | 6篇 |
1984年 | 8篇 |
1983年 | 9篇 |
1982年 | 12篇 |
1981年 | 7篇 |
1980年 | 10篇 |
1979年 | 10篇 |
1978年 | 4篇 |
1977年 | 5篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1971年 | 2篇 |
排序方式: 共有952条查询结果,搜索用时 15 毫秒
51.
B. Ghosh S.K. Bandyopadhyay H.G. Lele A.K. Ghosh 《Nuclear Engineering and Design》2009,239(2):327-337
The crack opening area has been estimated by various models for leak before break analysis of nuclear reactor systems. A number of linear elastic fracture mechanics models have been employed. A model has been derived based on Forman et al. [Forman, R.G., Hickman, J.C., Shivakumar, V., 1985. Stress intensity factors for circumferential through cracks in hollow cylinders subjected to combined tension and bending loads. Eng. Frac. Mech. 21, 563-571] model for stress intensity factors. The linear elastic fracture models entail the use of plasticity corrections. The convergence behaviour of the iterative implementation for plasticity correction has been studied. An elasto-plastic fracture mechanics model has also been adopted for comparative study undertaken here. The range of applicability of the models has been reviewed. 相似文献
52.
Bandyopadhyay B. Avinash Upadhye Osman Ismail 《Automatic Control, IEEE Transactions on》1997,42(8):1127-1130
The paper presents the γ-δ Routh approximation for interval systems. The interval γs and δs are evaluated for the higher order interval systems, and then an rth-order approximant is obtained by retaining the first r, interval δs, and γs. A numerical example illustrates the procedure 相似文献
53.
J. B. Mandal B. Bandyopadhyay B. Ghosh H. Rajagopal A. Sequeira J. V. Yakhmi 《Journal of Superconductivity and Novel Magnetism》1996,9(2):253-257
Rietveld analysis of powder neutron diffraction pattern recorded on Sr-based 1201-phase superconductor (T c =53 K), (Hg0.7Cr0.3)Sr2CuO4+δ shows that the oxygen atoms at O(3) site are disordered atx=y=0.3712. This fourfold split site has a total combined occupancy of ~80% and is the only occupied site in the (Hg, Cr)O plane. 相似文献
54.
A. K. Bandyopadhyay P. Auric J. Phalippou J. Zarzycki 《Journal of Materials Science》1980,15(8):2081-2090
The Mössbauer and ESR spectra and internal friction behaviour of Na2O-3SiO2 glasses having different redox ratios have been studied. As the redox ratio changes over a considerable range, there is a significant structural change associated with both the Fe3+ and Fe2+ ions, as evidenced from the analysis of the molar volume and Mössbauer data. The ESR data qualitatively supports the Mössbauer data on the Fe3+ ions. The change of internal friction behaviour of these glasses around 50% Fe3+ is described in terms of the structural changes associated with the Fe ions, which is thought to influence the oxygen structure of these glasses. The importance of this structural change on the electronic conductivity behaviour of these types of glasses is mentioned. 相似文献
55.
Gopal K. Bandyopadhyay Hem Shanker Ray 《Metallurgical and Materials Transactions B》1971,2(11):3055-3061
An electromotive force cell employing the ZrO2-CaO solid electrolyte has been set up to investigate the kinetics of dissolution of oxygen in molten lead under various oxidizing
conditions. The cell may be written as
The cell has been so designed that the electrode chambers are completely isolated from each other. The oxygen in lead is
first reduced to a very low value by bubbling hydrogen. subsequently, oxygen dissolution is achieved through gas diffusion
across the free surface or through bubble metal interaction. During all these reactions the electromotive force of the cell
changes continuously and is automatically recorded. The diffusion coefficient of oxygen in lead, as calculated from the experimental
data, is 1.29×10−5 sq cm per sec and the liquid phase mass transfer coefficient is estimated to be 0.035 cm per sec at 750°C. 相似文献
56.
Nanda De Abhijit Sengupta Subir Bandyopadhyay Pradip K. Srimani 《Information Sciences》1980,22(2):131-138
A new necessary and sufficient condition for t-diagnosability of a system is proposed. It is shown that the new scheme is computationally more efficient than the existing one for checking the diagnosability of a system. 相似文献
57.
Innumerable variety of metal niobates containing diverse M2O: Nb2O5 ratios are reported in the literature but three definite species could only be recognised — ortho, meta and the normal hexaniobates. These three types have been correlated and are shown to be the derivatives of the isopolyniobic acid. The stoichiometric mixed niobates can be derived from the metaniobates and their facile transformation to the perovskite type of lattice has been explained. The nonstoichiometric mixed niobates with cubic perovskite structure exhibit ‘bronze’ properties and their compositions are derived from the structure of the parent metaniobate. All these formulations agree with the compositions and the properties of known species. 相似文献
58.
59.
60.
This article, presents discrete sliding mode control algorithm using multirate output feedback for control of stepper motor. The algorithm developed by the authors uses past output samples and past control inputs. When all the states of the system are neither physical variable nor available for measurement, multirate output feedback can be used. The stepper motor is known to be a differentially flat system. The dynamics of the stepper motor are highly nonlinear, hence feedback linearization based on endogenous feedback has been used. The linear model is obtained and multirate output feedback-based discrete sliding mode control has been designed. The discrete sliding mode control with multirate output feedback has been applied for regulator as well as tracking case for the motor. The proposed algorithm uses only two outputs. It is essentially shown that first output needs to be sampled only once and second output must be sampled at least thrice in every τ sampling interval in order to achieve acceptable performance. The system parameter variation has been considered and the results obtained are found to be satisfactory. Thus, it has been shown that discrete sliding mode control algorithm using multirate output feed back can be extended to a class of nonlinear MIMO system. 相似文献