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121.
Wael E. Houssen Dr. Stephen H. Wright Dr. Arnout P. Kalverda Dr. Gary S. Thompson Dr. Sharon M. Kelly Dr. Marcel Jaspars Prof. 《Chembiochem : a European journal of chemical biology》2010,11(13):1867-1873
The solution structure of the leader sequence of the patellamide precursor peptide was analysed by using CD and determined with NOE‐restrained molecular dynamics calculations. This leader sequence is highly conserved in the precursor peptides of some other cyanobactins harbouring heterocycles, and is assumed to play a role in targeting the precursor peptide to the post‐translational machinery. The sequence was observed to form an α‐helix spanning residues 13–28 with a hydrophobic surface on one side of the helix. This hydrophobic surface is proposed to be the site of the initial binding with modifying enzymes. 相似文献
122.
Ongoing development of solid oxide fuel cell (SOFC) technology coincides with a rapid increase in legislation aiming to control the environmental impacts of products across their life cycle. A risk-based method is used to explore the potential future impacts of this body of legislation on the technology. Legislation controlling the use of hazardous materials is one area of significance. Under the new European REACH Regulation some nickel compounds, used widely throughout general industry but also in the fabrication of anode structures, may fall under the classification of a substance of very high concern (SVHC) in future, which presents a risk of restrictions being placed on their continued use. This risk must drive the development of alternative anode materials, or requires the SOFC industry to identify a socio-economic argument justifying exemption from any future restrictions. A legislative trend establishing recycling requirements for end-of-life products is also identified as having a potential future impact on the technology. Recycling strategies for SOFC products must be considered, prior to commercialisation. It is proposed that failure to meet these future environmental requirements may be detrimental to the perception of SOFC technology, the demand for which is substantially driven by the environmental benefits offered over incumbent power generation technologies. The consideration of these issues in the design of commercial products will mitigate this risk. 相似文献
123.
Wright Kathleen M.; Cabrera Oscar A.; Bliese Paul D.; Adler Amy B.; Hoge Charles W.; Castro Carl A. 《Canadian Metallurgical Quarterly》2009,6(2):108
The present study examined the effects of leadership and unit cohesion on mental health stigma and perceived barriers to care. A sample of 680 soldiers from combat support units were surveyed 3 months after their return from combat operations in Iraq. The survey included scales on psychological symptoms and perceptions of leader behaviors and unit cohesion, as well as items assessing stigma and barriers to care. The sample was used to test the independent and interactive effects of leadership and unit cohesion on soldiers’ perceptions of stigma and barriers to care. Analyses yielded significant interaction effects between leadership and cohesion in predicting stigma and barriers to care, while controlling for the effects of mental health symptoms. Soldiers who rated their leaders more highly and who reported higher unit cohesion also reported lower scores on both stigma and perceived barriers to care. Thus, positive leadership and unit cohesion can reduce perceptions of stigma and barriers to care, even after accounting for the relationship between mental health symptoms and these outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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126.
C. Celeste Trujillo Amanda J. Wright 《Journal of the American Oil Chemists' Society》2010,87(7):715-730
Solid lipid particles (SLP) are one strategy for encapsulating lipophilic molecules, including for controlled release and
enhanced bioavailability applications. SLP based on fully hydrogenated canola stearin (CaSt, 5, 10, 20, and 30 wt%) and the
non-ionic surfactant Poloxamer 188 (P188, 0.0, 0.5, 1.0, 2.5, 5.0 and 10.0 wt%) were produced by high pressure melt homogenization
using a microfluidizer. Spherical particles in the region of 140 nm were formed, depending on compostion and processing parameters.
Surfactant concentration and pressure had a significant influence on particle diameter (P < 0.05), although number of homogenization cycles did not (P > 0.05). A maximum surfactant surface load of approximately 4 mg m−2 was observed and, at or above 2.5% P188, excess surfactant was present in the continuous phase after production. P188 had
the effect of decreasing particle size and facilitating transitions from the α to the β polymorph (P < 0.05) both through surface nucleation and size reduction effects. A stability study of the 10% CaSt SLP with 0.0, 1.0,
or 5.0% P188 revealed particle growth for the 0.0 and 1.0% P188 SLP, especially at 20 versus 4 °C, but no changes in the 5.0%
P188 SLP, which were exclusively in the β form, at both temperatures for up to 240 days. 相似文献
127.
D. Brandt M. Asai P. L. Brink B. Cabrera E. do Couto?e?Silva M. Kelsey S. W. Leman K. McArthy R. Resch D. Wright E. Figueroa-Feliciano 《Journal of Low Temperature Physics》2012,167(3-4):485-490
There is a growing interest in cryogenic calorimeters with macroscopic absorbers for applications such as dark matter direct detection and rare event search experiments. The physics of energy transport in calorimeters with absorber masses exceeding several grams is made complex by the anisotropic nature of the absorber crystals as well as the changing mean free paths as phonons decay to progressively lower energies. We present a Monte Carlo model capable of simulating anisotropic phonon transport in cryogenic crystals. We have initiated the validation process and discuss the level of agreement between our simulation and experimental results reported in the literature, focusing on heat pulse propagation in germanium. The simulation framework is implemented using Geant4, a toolkit originally developed for high-energy physics Monte Carlo simulations. Geant4 has also been used for nuclear and accelerator physics, and applications in medical and space sciences. We believe that our current work may open up new avenues for applications in material science and condensed matter physics. 相似文献
128.
W. A. Wright 《摩擦学汇刊》2013,56(4):349-356
The increasing use of complex hydraulic systems has resulted in an increasing demand for bulk modulus data. Reliable data are difficult and expensive to obtain. The isothermal secant and tangent bulk moduli of petroleum oils and pure hydrocarbons have been studied in detail. Generalizations of the relationships were achieved. Charts are given to enable prediction of these moduli and densities from 0 to 500 F, over a pressure range of more than 100,000 psi with a minimum of calculation. The average error is less than 1.0%. The only required data are the density of the oil at atmospheric pressure and the desired temperature. Oil type or viscosity does not affect the result. 相似文献
129.
An extension to the Rasch model for fundamental measurement is described in which there is parameterization not only for examinee ability and item difficulty but also for judge severity. Variants of this model are discussed and judging plans reviewed. Its use and characteristics are explained by an application of the model to an empirical testing situation. A comparison with Generalizability Theory using a common data set is presented as a contrast in approaches to resolving judge indeterminacy. 相似文献
130.
Wright TJ 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2002,360(1801):2873-2888
The earthquake cycle is poorly understood. Earthquakes continue to occur on previously unrecognized faults. Earthquake prediction seems impossible. These remain the facts despite nearly 100 years of intensive study since the earthquake cycle was first conceptualized. Using data acquired from satellites in orbit 800 km above the Earth, a new technique, radar interferometry (InSAR), has the potential to solve these problems. For the first time, detailed maps of the warping of the Earth's surface during the earthquake cycle can be obtained with a spatial resolution of a few tens of metres and a precision of a few millimetres. InSAR does not need equipment on the ground or expensive field campaigns, so it can gather crucial data on earthquakes and the seismic cycle from some of the remotest areas of the planet. In this article, I review some of the remarkable observations of the earthquake cycle already made using radar interferometry and speculate on breakthroughs that are tantalizingly close. 相似文献