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排序方式: 共有1031条查询结果,搜索用时 350 毫秒
51.
Pranesh Sengupta 《Journal of Nuclear Materials》2006,350(1):66-73
Understanding the mode of interaction between borosilicate melt and Inconel is important for long time usage of melter pot in vitrification plant. The present study shows that significant elemental exchanges take place across the borosilicate melt/Inconel interface resulting in the development of (Fe, Ni)CrO4 needle and (Fe, Ni)Cr2O4 cubic phases. This results in significant depletion of Cr within Inconel near the interface. Beside these, CrB precipitates formed along the Inconel grain boundaries. 相似文献
52.
In this paper, we present a novel representation of the human face for estimating the orientation of the human head in a two dimensional intensity image. The method combines the use of the much familiar eigenvalue based dissimilarity measure with image based rendering. There are two main components of the algorithm described here: the offline hierarchical image database generation and organization, and the online pose estimation stage. The synthetic images of the subject's face are automatically generated offline, for a large set of pose parameter values, using an affine coordinate based image reprojection technique. The resulting database is formally called as the IBR (or image based rendered) database. This is followed by the hierarchical organization of the database, which is driven by the eigenvalue based dissimilarity measure between any two synthetic image pair. This hierarchically organized database is a detailed, yet structured, representation of the subject's face. During the pose estimation of a subject in an image, the eigenvalue based measure is invoked again to search the synthetic (IBR) image closest to the real image. This approach provides a relatively easy first step to narrow down the search space for complex feature detection and tracking algorithms in potential applications like virtual reality and video-teleconferencing applications. 相似文献
53.
High-performance affinity chromatography and zonal elution studies were used to examine the binding that takes place between the drug clomiphene and the protein human serum albumin (HSA). Equations were derived to describe the behavior of zonal elution experiments in which a solubilizing agent is present in the mobile phase to aid in the dissolution of a competing agent or injected analyte. These equations were then used to determine the association equilibrium constants for the clomiphene/HSA system, with beta-cyclodextrin being used as a complexation agent to improve the water solubility of cis- and trans-clomiphene without affecting the nature of their binding to HSA. It was found in these studies that both cis- and trans-clomiphene have 1:1 interactions at a common binding region on HSA (association constants at pH 7.4 and 37 degrees C: cis, 7.5 x 10(6) M-1; trans, 1.3 x 10(6) M-1). Further competition experiments between cis- or trans-clomiphene and various site-selective probes indicated that the clomiphene-binding region is the same as the proposed tamoxifen site of HSA. The approach and equations used within this report are general ones that can be applied to zonal elution studies of other solute-ligand systems in which one or more of the test components have limited solubility in the desired mobile phase. 相似文献
54.
55.
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
56.
P. J. Sunder C. V. Ramakrishnan S. Sengupta 《International journal for numerical methods in engineering》1983,19(8):1183-1192
The results of the finite element analysis of 3-ply laminated conical shells with light core for linear panel flutter are presented and certain advantages of such shells discussed. 相似文献
57.
Machining of cooling holes on thermal barrier coated superalloy components using a nanosecond (ns) laser generates considerable collateral damage such as recast layer, spatter and delamination of the ceramic coating. However, recent studies have suggested that these damages can be virtually eliminated by machining with femtosecond (fs) lasers. A detailed study on the microstructural characteristics of fs laser machined holes with diameters of 300 μm and 600 μm, generated on thermal barrier coated superalloy CMSX4 under various processing conditions has been conducted. Features examined include the shape, size and the surface finish of the hole wall. Femtosecond laser machined holes with a surface roughness of less than 2 μm and no major collateral damage could be generated in coated samples up to a thickness of 1.5 mm. The machining was found to cause minor ablative material removal from the top ceramic layer within 100 μm of the outer edge of the hole. The presence of machined holes did not affect the thermal cycling life at 1100 °C of the coated samples. 相似文献
58.
S. K. Sen A. Ray R. Avtar S. K. Dhua M. S. Prasad P. Jha P. P. Sengupta S. Jha 《Journal of Materials Engineering and Performance》1998,7(4):504-510
For the first time in India, quenched-and-tempered (Q&T) plates of a copper-bearing high-strength lowalloy (HSLA) steel have
been commercially developed for naval structural applications. A 50 ton production heat was made through electric arc furnace
(EAF)-vacuum arc degassing (VAD) route and continuously cast into 170 mm thick slabs. These slabs were conditioned, reheated
in walking-beam furnace and hot rolled in plate mill into plates of 10 to 16 mm thickness. The as-rolled plates were hardened
through oil quenching and subsequently tempered (aged) at 630 ‡C to achieve the combination of highstrength and good low-temperature
impact toughness.
The microstructures of heat treated plates showed fine acicular ferrite with grain sizes ranging between ASTM No. 9 and 10.
From the standpoint of tensile properties, Q&T plates of all thicknesses exhibited significantly higher yield strengths than
the minimum stipulated value of 552 MPa for HY-80/HSLA-80 steels. The elongation (22.20 to 26.00%) and reduction in area (62.12
to 67.62%) values achieved also exceeded the respective minimum requirements of 20 and 50% stipulated for such steels. The
trend in variation of Charpy V-notch (CVN) impact energies at room temperature, -18, and -62 ‡C not only showed significantly
higher values than that stipulated for HY-80 and HSLA-100 steels at -18 ‡C, but also indicated that the CVN impact energies
achieved (105.15 to 144.25 J) at -62 ‡C were higher than the estimated value of 90 J for HSLA-80/HSLA-100 steels at this temperature. 相似文献
59.
I. N. Sengupta 《Scientometrics》1989,17(3-4):289-300
Ranking lists of periodicals in different scientific disciplines are generally based on the total number of citations derived from a group of source journals with equal weightage given to all citations irrespective of chronology. As a result, in all these ranking lists, the position occupied by the post-war journals, may not be an accurate index of their demand or usefulness to research workers in the concerned field. This may happen because the quantum of published literature in the new journals is limited by the period for which they have been in existence, which is in many cases less than 20 years. Moreover, many of the post-war journals appearing in all these recent ranking lists have started publication even after 1960s, and their enumerated citations cover in fact a variable period of less than 20 years unlike in the case of pre-war journals. To avoid such discriminating against new journals which necessarily have fewer citation credits Sengupta suggested earlier an off-setting weightage formula which has been applied in this paper to rerank microbiology periodicals. A revised ranking list in the field of microbiology has been recommended in preference to the earlier one compiled by Sengupta. Results and findings, after application of the weightage formula, have been presented and discussed in this paper. 相似文献
60.
S. Sengupta H. Soda A. McLean J. W. Rutter 《Metallurgical and Materials Transactions A》2000,31(1):239-248
A ternary eutectic alloy with a composition of 57.2 pct Bi, 24.8 pct In, and 18 pct Sn was continuously cast into wire of
2 mm diameter with casting speeds of 14 and 79 mm min−1 using the Ohno Continuous Casting (OCC) process. The microstructures obtained were compared with those of statically cast
specimens. Extensive segregation of massive Bi blocks, Bi complex structures, and tinrich dendrites was found in specimens
that were statically cast. Decomposition of γSn by a eutectoid reaction was confirmed based on microstructural evidence. Ternary eutectic alloy with a cooling rate of
approximately 1 °C min−1 formed a double binary eutectic. The double binary eutectic consisted of regions of BiIn and decomposed γSn in the form of a dendrite cell structure and regions of Bi and decomposed γSn in the form of a complex-regular cell. The Bi complex-regular cells, which are a ternary eutectic constituent, existed
either along the boundaries of the BiIn-decomposed γSn dendrite cells or at the front of elongated dendrite cell structures. In the continuously cast wires, primary Sn dendrites
coupled with a small Bi phase were uniformly distributed within the Bi-In alloy matrix. Neither massive Bi phase, Bi complex-regular
cells, nor BiIn eutectic dendrite cells were observed, resulting in a more uniform microstructure in contrast to the heavily
segregated structures of the statically cast specimens. 相似文献