全文获取类型
收费全文 | 768篇 |
免费 | 42篇 |
专业分类
电工技术 | 23篇 |
综合类 | 1篇 |
化学工业 | 302篇 |
金属工艺 | 20篇 |
机械仪表 | 35篇 |
建筑科学 | 10篇 |
矿业工程 | 4篇 |
能源动力 | 24篇 |
轻工业 | 70篇 |
水利工程 | 2篇 |
石油天然气 | 2篇 |
无线电 | 41篇 |
一般工业技术 | 108篇 |
冶金工业 | 13篇 |
原子能技术 | 4篇 |
自动化技术 | 151篇 |
出版年
2023年 | 8篇 |
2022年 | 23篇 |
2021年 | 39篇 |
2020年 | 13篇 |
2019年 | 23篇 |
2018年 | 20篇 |
2017年 | 23篇 |
2016年 | 22篇 |
2015年 | 23篇 |
2014年 | 44篇 |
2013年 | 82篇 |
2012年 | 46篇 |
2011年 | 67篇 |
2010年 | 36篇 |
2009年 | 43篇 |
2008年 | 44篇 |
2007年 | 24篇 |
2006年 | 21篇 |
2005年 | 22篇 |
2004年 | 13篇 |
2003年 | 18篇 |
2002年 | 15篇 |
2001年 | 7篇 |
2000年 | 8篇 |
1999年 | 9篇 |
1998年 | 9篇 |
1997年 | 9篇 |
1996年 | 7篇 |
1995年 | 11篇 |
1994年 | 8篇 |
1993年 | 5篇 |
1992年 | 2篇 |
1991年 | 5篇 |
1990年 | 2篇 |
1989年 | 5篇 |
1988年 | 3篇 |
1987年 | 5篇 |
1986年 | 3篇 |
1985年 | 7篇 |
1984年 | 5篇 |
1983年 | 6篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 4篇 |
1977年 | 3篇 |
1975年 | 3篇 |
1966年 | 1篇 |
1965年 | 1篇 |
1961年 | 1篇 |
排序方式: 共有810条查询结果,搜索用时 28 毫秒
61.
A case of using the Semantic Interoperability Framework for custom orthopedic implants manufacturing
Milan Zdravković Miroslav Trajanović Miloš Stojković Dragan Mišić Nikola Vitković 《Annual Reviews in Control》2012,36(2):318-326
The efficiency and effectiveness of the daily practice in orthopedic surgery depend on the availability, interoperability and unique access to a wide set of information, related to the patient’s medical record and diagnosis, domain knowledge and available resources and staff. The most important of the tangible resources, needed for the therapeutic or preventive actions are orthopedic implants. In some cases, the implants may be highly complex and customized products, which need to be manufactured (assembled) on basis of the above information in a shortest possible timeframe. In this paper, the case of the custom orthopedic implants manufacturing is described from the perspective of the collaborative enterprising, with special consideration of the interoperability issues of the involved enterprise collaboration. It is shown how the previously developed Semantic Interoperability Framework can be used to improve the efficiency of the manufacturing and other relevant processes. 相似文献
62.
For the first time new type of liquid single crystal elastomers forming the chiral smectic A* (SmA*) phase has been prepared using chiral lactic acid derivative as a co-monomer. The synthesis and the basic characterization of the ferroelectric liquid crystalline co-monomer based on differential scanning calorimetry and small/wide-angle X-ray scattering are reported and discussed. The monomer possesses the paraelectric SmA* and the ferroelectric SmC* phases over a broad temperature range. The preparation of new smectic liquid crystalline elastomers together with characterization of their mesomorphic and structural properties is also reported. New elastomers possess the orthogonal paraelectric SmA* phase over 50 K broad temperature range. 相似文献
63.
Miroslav Pohanka 《International journal of molecular sciences》2014,15(6):9809-9825
Acetylcholinesterase (AChE) inhibitors are widely used for the symptomatic treatment of Alzheimer’s disease and other dementias. More recent use is for myasthenia gravis. Many of these inhibitors interact with the second known cholinesterase, butyrylcholinesterase (BChE). Further, evidence shows that acetylcholine plays a role in suppression of cytokine release through a “cholinergic anti-inflammatory pathway” which raises questions about the role of these inhibitors in the immune system. This review covers research and discussion of the role of the inhibitors in modulating the immune response using as examples the commonly available drugs, donepezil, galantamine, huperzine, neostigmine and pyridostigmine. Major attention is given to the cholinergic anti-inflammatory pathway, a well-described link between the central nervous system and terminal effector cells in the immune system. 相似文献
64.
Zoran Djuric Zoran Djinovic Zarko Lazic Jozef Piotrowski 《Journal of Electronic Materials》1988,17(3):223-228
A quantitative model of isothermal vapor phase epitaxy is proposed. It can be applied to both closed and open tube systems.
This model enables the prediction of compositional profiles of the layers grown by isothermal vapor phase epitaxy with dependence
on the growth parameters and thermodynamical data of the (Hg,Cd)Te system. The dependence of compositional profiles of the
ISOVPE layers on temperature and time of deposition, source to substrate spacing, mercury and inert gas pressures are discussed
for both solid and liquid sources. Modification of the compositional profiles by the postgrowth annealing has also been studied.
The proper choice of growth and annealing parameters makes the optimization of the profiles possible. The calculated profiles
are compared with the experimental data and a satisfactory quantitative fit is found in most cases. The possible reasons for
remaining discrepancies are discussed. 相似文献
65.
Ivan Chajda Miroslav Kola?ík 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(7):1213-1218
We introduce the concept of very true operator on an effect algebra. Although an effect algebra is only partial, we define it in the way which is in accordance with traditional definitions in residuated lattices or basic algebras. This is possible if we require monotonicity as an additional condition. We prove that very true operators on effect algebras can be characterized by means of certain subsets which are conditionally complete. 相似文献
66.
Miroslav Kárný Marko Ruman 《International Journal of Adaptive Control and Signal Processing》2021,35(5):660-675
Any knowledge extraction relies (possibly implicitly) on a hypothesis about the modelled-data dependence. The extracted knowledge ultimately serves to a decision-making (DM). DM always faces uncertainty and this makes probabilistic modelling adequate. The inspected black-box modeling deals with “universal” approximators of the relevant probabilistic model. Finite mixtures with components in the exponential family are often exploited. Their attractiveness stems from their flexibility, the cluster interpretability of components and the existence of algorithms for processing high-dimensional data streams. They are even used in dynamic cases with mutually dependent data records while regression and auto-regression mixture components serve to the dependence modeling. These dynamic models, however, mostly assume data-independent component weights, that is, memoryless transitions between dynamic mixture components. Such mixtures are not universal approximators of dynamic probabilistic models. Formally, this follows from the fact that the set of finite probabilistic mixtures is not closed with respect to the conditioning, which is the key estimation and predictive operation. The paper overcomes this drawback by using ratios of finite mixtures as universally approximating dynamic parametric models. The paper motivates them, elaborates their approximate Bayesian recursive estimation and reveals their application potential. 相似文献
67.
Yannick Phulpin Miroslav Begovic Marc Petit Damien Ernst 《International Journal of Electrical Power & Energy Systems》2009,31(9):482-488
This paper addresses the problem of centralized optimization of an interconnected power system partitioned into several regions controlled by different transmission system operators (TSOs). It is assumed that those utilities have agreed to transferring some of their competencies to a centralized control center, which is in charge of setting the control variables in the entire system to satisfy every utility’s individual objective. This paper proposes an objective method for centralized optimization of such multi-TSO power systems, which relies on the assumption that each TSO has a real-valued optimization function focusing on its control area only. This method is illustrated on the IEEE 118 bus system partitioned into three TSOs. It is applied to the optimal reactive power dispatch problem, where the control variables are the voltage settings for generators and compensators. After showing that the method has some properties of fairness, namely freedom from envy, efficiency, accountability, and altruism, we emphasize its robustness with respect to certain biased behavior of the different TSOs. 相似文献
68.
The aging of aqueous solutions of polyacrylamide which appears experimentally as a decrease of solution viscosity and which is probably caused by microorganisms may be prevented by the addition of a small amount (0.02 wt.-%) of an antimicrobial agent such as sodium azide. Aluminium chloride causes a very strong decrease of the viscosity during a prolongated storing time. The addition of aluminium ions to the polymer solution leads to a complexing of amidic groups with aluminium cations and probably also to decrease of the dimensions of individual polymer coils. The viscous flow of aqueous solutions of polyacrylamide and hydrolyzed polyacrylamides was studied as a dependence of the shear gradient D on the shear stress τ and was described by the relation D = k · τn, where k and n denote constants. Both constants depend on the polymer concentration, the degree of polymerization and the content of carboxylic groups in the polymer. The greatest deviations from the Newtonian behaviour were found in the range of molecular weights over 2 · 106 g/mol and practically no deviations were observed for polyacrylamide with molecular weights below 1 · 106 g/mol. The dependence of the viscosity on the shearing time at different shear rates (300, 600 and 1200 s?1) which was observed in solutions of polyacrylamide, hydrolyzed polyacrylamide and poly-(N,N-dimethyl)-acrylamide was explained by an entanglement model. 相似文献
69.
Vera P. Pavlović Jelena D. Vujančević Pavle Mašković Jovana Ćirković Jelena M. Papan Darko Kosanović Miroslav D. Dramićanin Predrag B. Petrović Branislav Vlahović Vladimir B. Pavlović 《Journal of the American Ceramic Society》2019,102(12):7735-7745
Titanium dioxide is a photocatalyst, known not only for its ability to oxidize organic contaminants, but also for its antimicrobial properties. In this article, significant enhancement of the antimicrobial activity of TiO2 (up to 32 times) was demonstrated after its activation by ball milling. The antimicrobial activity was analyzed for one fungal and 13 bacterial ATCC strains using the microdilution method and recording the minimum inhibitory concentration (MIC) values. In order to further investigate the correlation between the mechanical activation of TiO2 and its antimicrobial activity, the structure, morphology and phase composition of the material were studied by means of Electron Microscopy, X-ray diffraction and nitrogen adsorption-desorption measurements. UV-Vis diffuse reflectance spectra were recorded and the Kubelka-Munk function was applied to convert reflectance into the equivalent band gap energy (Eg) and, consequently, to investigate changes in the Eg value. X-ray photoelectron spectroscopy was used to analyze the influence of mechanical activation on the Ti 2p and O 1s spectra. The presented results are expected to enable the development of more sustainable and effective advanced TiO2-based materials with antimicrobial properties that could be used in numerous green technology applications. 相似文献
70.
Helena Valentová Miroslav Kašpar Věra Hamplová Karel Bouchal Michal Ilavský Antonín Sikora Daniel Froelich René Muller 《Polymer Bulletin》1997,38(2):219-226
The dynamic mechanical behaviour of random copolymers of LC monomer-1-(hexyloxycarbonyl)ethyl 4-[4-(methacryloyloxy)benzoyloxy]benzoate
(HB) and octyl methacrylate (OMA) was studied in the main transition and flow regions. Even though the aliphatic end groups
of the side chain of HB and OMA are roughly the same, the T
g temperature of poly(HB) is ∼ 80 K higher than that of poly(OMA); this fact is due to the presence of the stiff phenyl benzoate
mesogenic group in the side chain of HB. With increasing content of OMA in the copolymer the superimposed curves of the storage
G′
p and loss G′′
p moduli at a constant temperature shift towards shorter frequencies. It has been shown that this shift is mainly due to an
increase of the free volume in the copolymers with increasing content of OMA. While HB monomer shows liquid crystalline (LC)
properties, its polymer (poly(HB)) and random copolymers with OMA show only isotropic thermal behaviour because no flexible
spacer is present in the side chain of HB which would decouple the main chain and mesogenic group motions. This means that
neither the homopolymer of HB, nor its copolymers with a flexible comonomer retain the LC properties of the starting LC monomer,
HB.
Received: 26 September 1996/Revised: 7 November 1996/Accepted: 7 November 1996 相似文献