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排序方式: 共有341条查询结果,搜索用时 250 毫秒
21.
Alterations in the bulk (surface) magnetic properties of amorphous Fe80 B20?x C x (0 5x ? 10) and Fe82 B18?y Ge y (0 ?y ? 6) alloys, caused by isothermal annealing (mechanical polishing) of the alloy ribbons at a temperature T A = 0.5T cr (whereT cr is the crystallization temperature) for various lengths of time,t a, ranging from 0 to 240 min, have been studied by measuring the corresponding changes in the ferromagnetic resonance (FMR) linewidth, AHPP, and resonance field,H res. Polishing induces significant changes in bothH res and ΔH pp but leaves their composition dependence practically unaltered. By comparison, isothermal annealing has no influence onH res for ali the investigated alloy compositions whereas it affects ΔH pp to different extents depending on the alloy composition. Physical implications of these results are discussed in terms of the effect of surface and annealing treatments on various contributions toH res and AHPP in the glassy alloys in question. 相似文献
22.
The reconfiguration capability of modern FPGA devices can be utilized to execute an application by partitioning it into multiple segments such that each segment is executed one after the other on the device. This division of an application into multiple reconfigurable segments is called temporal partitioning. We present an automated temporal partitioning technique for acyclic behavior level task graphs. To be effective, any behavior-level partitioning method should ensure that each temporal partition meets the underlying resource constraints. For this, a knowledge of the implementation cost of each task on the hardware should be known. Since multiple implementations of a task that differ in area and delay are possible, we perform design-space exploration to choose the best implementation of a task from among the available implementations.To overcome the high reconfiguration overhead of the current day FPGA devices, we propose integration of the temporal partitioning and design space exploration methodology with block-processing. Block-processing is used to process multiple blocks of data on each temporal partition so as to amortize the reconfiguration time. We focus on applications that can be represented as task graphs that have to be executed many times over a large set of input data. We have integrated block-processing in the temporal partitioning framework so that it also influences the design point selection for each task. However, this does not exclude usage of our system for designs for which block-processing is not possible. For both block-processing and non block-processing designs our algorithm selects the best possible design point to minimize the execution time of the design.We present an ILP-based methodology for the integrated temporal partitioning, design space exploration and block-processing technique that is solved to optimality for small sized design problems and in an iterative constraint satisfaction approach for large sized design problems. We demonstrate with extensive experimental results for the Discrete Cosine Transform (DCT) and random graphs the validity of our approach. 相似文献
23.
Savita Kaul Jyoti Porwal M. O. Garg 《Journal of the American Oil Chemists' Society》2010,87(8):903-908
The purpose of the present study was to reduce the cost and increase the efficiency of biodiesel production by reactive extraction
(in situ) of Jatropha seeds. Oil from the seeds was extracted and reacted in a single step. Experimental studies have been
carried out to maximize the yield of biodiesel by varying the reaction parameters viz. seed size (<0.85 mm to >2.46 mm), seed/solvent
ratio (w/w) (1:2.6–1:7.8) and catalyst concentration (0.05–0.1 M). Under the optimized conditions: seed size (>2.46 mm), seed/solvent
ratio (w/w) (1:7.8), catalyst concentration (0.1 M) and reaction time 1 h, approximately 98% conversion to biodiesel was achieved
meeting International (ASTM) as well as National (BIS) specifications. The results were supported by HPLC analysis. 相似文献
24.
Matured biogas production technology has led to the development of a number of biogas appliances for lighting, power generation, and cooking. The most promising among them is the biogas stove, to meet the energy requirement for cooking application at domestic as well as at the community level. In this paper, an attempt has been made to design and develop a community biogas stove for baking chapatti (bread) or other food items on a hotplate for canteen or community purposes. The performance of the stove was evaluated by using a 25 m3 floating type biogas plant at Asha Dham Asharm, Udaipur, India. The gas consumption rating of the developed stove was 1 m3 (19 MJ/h) and the cooking efficiency of the stove was recorded to be about 43.96%. 相似文献
25.
D. P. Rodionov G. A. Dosovitskii A. R. Kaul’ I. V. Gervas’eva Yu. N. Akshentsev V. A. Kazantsev Yu. V. Khlebnikova V. A. Sazonova N. I. Vinogradova S. V. Samoilenkov S. N. Mudretsova A. V. Garshev 《The Physics of Metals and Metallography》2010,109(6):632-642
Based on the data of X-ray diffraction, electron-backscatter diffraction, dilatometry, thermal analysis, and scanning electron microscopy, we determined the optimum regimes of heat treatment of cold-rolled tape substrates of an alloy Ni88.4Cr9.2W2.4 that permit obtaining a perfect cube texture. It has been shown that the use of two-stage annealings makes it possible to obtain in this ternary nickel alloy a cube texture in which the scatter about the rolling direction (RD) and the transverse direction (TD) of the substrates varied within 6.75°–7.20° and 4.8°–5.4°, respectively. 相似文献
26.
R. A. Daryapurkar T. Nandy S. N. Kaul C. V. Deshpande L. Szpyrkowicz 《The International journal of environmental studies》2013,70(6):835-860
An approach has been made to evaluate the kinetic constants for a two stage anaerobic fixed film fixed bed reactor system treating tannery wastewater. The research reported herein is concerned with the bench scale performance evaluation of the reactor system treating the wastewater and application of the data to various models to evaluate the kinetic constants for substrate bio‐oxidation, biomass growth and biogas yield. 相似文献
27.
28.
The present study provides evidence to support that human platelets possess a 47 kDa dual functional molecule having thiol-oxidase activity as well as high affinity for the SRE sequence in the human genome. On the basis of these as well as earlier results, we propose that Receptor 'Ck' dependent regulation of this dual functional 47 kDa molecule may provide a mechanism for the maintenance of cellular cholesterol homeostasis. Further, this mechanism may also explain the molecular basis of cholesterol-feedback lesion observed under premalignant conditions. 相似文献
29.
SC Kaul EL Duncan A Englezou S Takano RR Reddel Y Mitsui R Wadhwa 《Canadian Metallurgical Quarterly》1998,17(7):907-911
The murine mortalin genes, mot-1 and mot-2, are members of the hsp70 family of proteins and differ from each other by only two amino acid residues. Mot-1 is expressed in normal cells and has pancytosolic cellular distribution whereas mot-2 is found in the perinuclear region of immortal cells. We report here that a high level of expression of mot-2 protein resulted in malignant transformation of cells as analysed by anchorage independent growth and nude mice assays. A high level of protein expression is attributed to the 900 bp 3' untranslated region of the cDNA which does not have any transforming activity per se. Mortalin cDNA clones isolated from human transformed cells were also found to have transforming activity in similar assays and a high level of expression was apparent in some of the human immortalized cells that showed non-pancytosolic mortalin immunofluorescence. Taken together, the data suggest that nonpancytosolic mortalin may have a role in tumorigenesis. 相似文献
30.
This paper presents a time-dependent periodic heat transfer analysis of a non-air-conditioned building having a south-facing wall of phase-changing component material (PCCM). A rectangular room (6 × 5 × 4 m) based on the ground is considered. The effects of heat transfer through walls and roof, heat conduction to the basement ground and furnishings, heat gain through window and heat loss due to air ventilation have been incorporated in the periodic time-dependent heat transfer analysis. The time-dependent heat flux through the PCCM south-facing wall has been obtained by defining the effective thermal properties of the PCCM for a conduction process with no phase change. Numerical calculations are made for a typical mild winter day (7 March 1979) at New Delhi for heat flux entering through the wall and inside air temperature. Further, a PCCM wall of smaller thickness is more desirable, in comparison to an ordinary masonry concrete wall, for providing efficient thermal energy storage as well as excellent thermal comfort in buildings. 相似文献