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排序方式: 共有619条查询结果,搜索用时 15 毫秒
471.
Przemysław Dąbrowski Grzegorz Łabuzek Tomasz Rachwalik Janusz Szmidt 《Information Processing Letters》2014
Nonlinear feedback shift registers (NLFSRs) are used to construct pseudorandom generators for stream ciphers. Their theory is not so complete as that of linear feedback shift registers (LFSRs). In general, it is not known how to construct all NLFSRs with maximum period. The direct method is to search for such registers with suitable properties. Advanced technology of parallel computing has been applied both in software and hardware to search for maximum period NLFSRs having a fairly simple algebraic normal form. 相似文献
472.
Tadeusz Knych Paweł Kwaśniewski Grzegorz Kiesiewicz Andrzej Mamala Artur Kawecki Beata Smyrak 《Metallurgical and Materials Transactions B》2014,45(4):1196-1203
Currently, there is a worldwide search for new forms of materials with properties that are significantly improved in comparison to materials currently in use. One promising research direction lies in the synthesis of metals containing modern carbon materials (e.g., graphene, nanotubes). In this article, the research results of metallurgical synthesis of a mixture of copper and two different kinds of carbon (activated carbon and multiwall carbon nanotubes) are shown. Samples of copper–carbon nanocomposite were synthesized by simultaneously exposing molten copper to an electrical current while vigorously stirring and adding carbon while under an inert gas atmosphere. The article contains research results of density, hardness, electrical conductivity, structure (TEM), and carbon decomposition (SIMS method) for the obtained materials. 相似文献
473.
474.
The article describes the problems with weldability of high-strength steels in the aquatic environment. The tendency of steel S355J2G3 and S500M to form cold cracks when welded in wet welding conditions has been experimentally evaluated. It was found that the tested steels have a high propensity to cracking. An experiment has been proposed and tested to evaluate the usefulness of the tempering bead technique as a method of improving the weldability of high-strength steels under water in wet welding conditions. 相似文献
475.
476.
Elzbieta Horszczaruk ;Piotr Brzozowski ;Grzegorz Adamczewski ;Tomasz Rudnicki 《土木工程与建筑:英文版》2014,(12):1549-1555
The design of unique chamber, in which the SCUWC (self-consolidating underwater concrete) can be tested under the impact of the hydrostatic pressure from 0.1 MPa to 0.5 MPa, is presented in the paper. The results of the preliminary tests of the effect of the hydrostatic pressure on the compressive strength of SCUWC were shown. The impact of the hydrostatic pressure on the compressive strength values of test specimens has been confirmed. There has been an increase in the strength of the specimens taken from the upper parts of the concrete samples. As it can be seen from the preliminary research, the differences in compressive strength are related to the differences that occur in the size and distribution of air voids in the samples taken from upper and lower parts of the test specimens. On the basis of the carried out investigations of the compressive strength, it can be concluded that the hydrostatic pressure has a favorable effect on the compressive strength of the tested specimens of SCUWC. Increase of the compressive strength is observed mostly in the upper layers of the samples. Preliminary analysis of the quantity and distribution of air pores in the samples of concrete subjected to pressure 0.5 MPa confirms the positive impact of the hydrostatic pressure on the layers close to the surface indicated by the absence of large air voids above 1,500μm and by reducing the quantity of air pores of size above 300μm. 相似文献
477.
Witold Gładkowski Grzegorz Kiełbowicz Anna Chojnacka Łukasz Bobak Radosław Spychaj Zbigniew Dobrzański Tadeusz Trziszka Czesław Wawrzeńczyk 《International Journal of Food Science & Technology》2014,49(8):1876-1885
The influence of feed supplemented with dietary sources of n‐3 polyunsaturated fatty acids (PUFAs), namely flaxseed and algae Schizochytrium sp., on the fatty acid composition of lipids from Japanese quail eggs was studied. Two groups of quails were fed for 19 weeks, starting from 6th week of life. Lipid fractions from dried egg mass of total of 4300 eggs of control and experimental group were analysed. The fatty acid profile was affected in both triacylglycerols and phospholipids. The significant (P < 0.05) increase in n‐3 PUFAs up to 7.33% in the total lipids, α‐linolenic acid (ALA, 18:3) up to 4.57% in triacylglycerols, docosahexaenoic acid (22:6, DHA) up to 23.91% in phosphatidylethanolamine and up to 4.35% in phosphatidylcholine as well as the significant (P < 0.05) reduction in n‐6/n‐3 ratio in the lipid fractions to the range of 0.9–3.7 was observed in experimental group. The incorporation of different n‐3 into lipids was selective: ALA was found in the triacylglycerol fraction, whereas EPA, DPA and DHA were detected in the phospholipid fractions, exclusively at sn‐2 position. The studies showed that the feeding quails with modified diets is effective way of biofortifying the eggs with nutritionally desired n‐3 PUFAs. 相似文献
478.
Bernd-Arno Behrens Hans Jürgen Maier Friedrich-Wilhelm Bach Wilfried Reimche Grzegorz Mroz Jens Schrödter Jan Jocker 《Production Engineering》2014,8(1-2):63-72
Information on the mechanical load which has been applied on a component during its lifecycle is becoming more and more interesting in order to assist the development of new generations of lightweight components. To collect this information from a large number of components in the field, cost-effective sensor techniques are required. The idea of the research presented in this paper is to qualify the base material of a component itself as a sensor. Load-induced changes in the microstructure of metastable austenitic sheet metals at the basis for this idea. Capabilities of increasing the sensitivity related to load-induced martensite phase transformations with the aid of metal forming operations as well as an approach to detect the direction of mechanical forces using embossed sensor fields are presented. The development of sensor fields based on FE-simulation as well as the results of experimental tests are discussed. 相似文献
479.
Stanislaw Penczek Julia B. Pretula Krzysztof Kaluzynski Grzegorz Lapienis 《Israel journal of chemistry》2012,52(3-4):306-319
Syntheses, some properties, and applications of the poly(alkylene phosphate)s prepared either by ring-opening polymerization (ROP) or by polycondensation are described mostly on the basis of the data from our laboratories. The ROP of some cyclic phosphates and H-phosphonates are living and/or controlled process. Transesterification of the products of the reaction of an excess of dimethylphosphonate with glycols leads to polymers with Mn close to 5×104. Poly(alkylene phosphate)s with five or six atoms in repeating units bear resemblance to the main chains of nucleic and teichoic acids. These and similar poly(alkylene phosphate)s with different repeating units were used as liquid membranes for the efficient separation of cations as well as to modify the medium for CaCO3 crystallization. In this latter process, a diblock copolymer with ionic and nonionic block was used. Poly(alkylene phosphate)s constituted the ionic block and the nonionic block was formed from poly(ethylene glycol); together with CaCO3 polymer inorganic hybrids were formed. 相似文献
480.
Extended viewing angle holographic display system with tilted SLMs in a circular configuration 总被引:1,自引:0,他引:1
This paper presents an extended viewing angle holographic display for reconstruction of real world objects in which the capture and display systems are decoupled. This is achieved by employing multiple tilted spatial light modulators (SLMs) arranged in a circular configuration. In order to prove the proper reconstruction and visual perception of holographic images the Wigner distribution function is employed. We describe both the capture system using a single static camera with a rotating object and a holographic display utilizing six tilted SLMs. The experimental results based on the reconstruction of computer generated and real world scenes are presented. The coherent noise removal procedure is described and implemented. The experiments prove the possibility to view images reconstructed in the display binocularly and with good quality. 相似文献