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991.
Herv Tettelin Agns Thierry Andr Goffeau Bernard Dujon 《Yeast (Chichester, England)》1998,14(7):601-616
The high resolution complete physical maps of chromosomes VII and XV were constructed to form the basis for sequencing these chromosomes as part of the European systematic sequencing programme of the yeast genome, using a unique cosmid library from strain FY1679, and an original top-down mapping strategy involving I-Sce I chromosome fragmentation. A total of 138 and 196 cosmid clones were used to construct the maps for VII and XV, respectively, forming two unique contigs that cover the entirety of chromosomes (1091 kb each), except the telomeric repeats. Colinearity of the cosmid inserts with yeast DNA was verified, and the physical maps were eventually compared with the independently generated genetic maps. © 1998 John Wiley & Sons, Ltd. 相似文献
992.
Denitza T. Krasteva Layne T. Watson Chuck Baker Bernard Grossman William H. Mason Raphael T. Haftka 《Concurrency and Computation》1999,11(8):435-459
Multidisciplinary design optimization (MDO) for large-scale engineering problems poses many challenges (e.g. the design of an efficient concurrent paradigm for global optimization based on disciplinary analyses, expensive computations over vast data sets, etc.). This work focuses on the application of distributed schemes for massively parallel architectures to MDO problems, as a tool for reducing computation time and solving larger problems. The specific problem considered here is configuration optimization of a high speed civil transport (HSCT), and the efficient parallelization of the embedded paradigm for reasonable design space identification. Two distributed dynamic load balancing techniques (random polling and global round robin with message combining) and two necessary termination detection schemes (global task count and token passing) were implemented and evaluated in terms of effectiveness and scalability to large problem sizes and a thousand processors. The effect of certain parameters on execution time was also inspected. Empirical results demonstrated stable performance and effectiveness for all schemes, and the parametric study showed that the selected algorithmic parameters have a negligible effect on performance. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
993.
Henry L. Friedman Robert A. Johnson Bernard Miller David R. Salem Richard S. Parnas 《Polymer Composites》1997,18(5):663-671
Forced in-plane flow of liquids through contiguous flat and curved regions of confined fabrics has been studied both as a general phenomenon and for predicting the flow of polymers during injection molding of monolithic composite structures with complex configurations. A controlled pressure difference is applied to drive the flow, while the mass flow rate is measured gravimetrically by Liquid/Air Displacement Analysis (LADA). Measurements have been carried out along fabric paths that are first vertical, then curved, and finally horizontal. Fluid flow equations have been adapted for analyzing flow in the flat sections, leading to the evaluation of permeability constants and capillary pressures. A saturated flow rate measured at constant hydrodynamic pressure is used to evaluate the overall permeability coefficient of the encapsulated fabric. Data are presented showing that permeability can be reduced as a consequence of flow through the curved region. 相似文献
994.
995.
Zhu Bin Liu Zhuang Wang Yanan Rolfe Bernard Wang Liang Zhang Yisheng 《Metallurgical and Materials Transactions A》2018,49(4):1304-1312
Metallurgical and Materials Transactions A - Application of quenching and partitioning process in hot stamping has proven to be an effective method to improve the plasticity of advanced... 相似文献
996.
Archana P Pant Theodore JK Radovich Ngyuen V Hue Stephen T Talcott Kristen A Krenek 《Journal of the science of food and agriculture》2009,89(14):2383-2392
BACKGROUND: Multiple studies have been reported on the effect of compost tea on suppression of certain plant diseases. However, relatively little work has been done to investigate the effect of vermicompost tea on yield and nutritional quality of vegetable crops. In this study, experiments were conducted to determine the effect of extraction method on vermicompost tea quality and subsequent effects on growth, mineral nutrients, phytonutrients and antioxidant activity of pak choi plants grown under organic (vermicompost) and synthetic (Osmocote) fertilisation. Three vermicompost teas obtained by different extraction methods, namely non‐aerated vermicompost tea (NCT), aerated vermicompost tea (ACT) and aerated vermicompost tea augmented with microbial enhancer (ACTME), were applied to the plants. Aerated water served as control. RESULTS: Mineral nutrients were significantly higher in ACTME compared with other teas, but total microbial population and activity did not differ with extraction method. All vermicompost teas similarly enhanced plant production, mineral nutrients and total carotenoids, and this effect was most prominent under organic fertilisation. Antioxidant activity and total phenolics were higher under organic compared with synthetic fertilisation. Vermicompost teas generally decreased phenolics under organic fertilisation and increased them under synthetic fertilisation compared with the control. CONCLUSION: The effect of vermicompost tea on crop growth is largely attributable to mineral nutrient, particularly N, uptake by plants. Non‐significant differences among extraction methods on plant response within fertiliser regimes suggest that aeration and additives are not necessary for growth promotion and nutrient quality under the conditions reported here. Copyright © 2009 Society of Chemical Industry 相似文献
997.
Rider R Kelley-Baker T Voas RB Murphy B McKnight AJ Levings C 《Accident; analysis and prevention》2006,38(3):482-489
The Preventing Alcohol-Related Convictions (PARC) program is a novel educational curriculum for first-time DUI offenders, with the ultimate goal of reducing DUI recidivism. It differs from traditional DUI education and prevention programs in that it does not suggest to DUI offenders that they must abstain from alcohol entirely or control their drinking to prevent a future DUI; rather, it teaches students to prevent a future DUI by not driving their cars to drinking events. Thus, the emphasis of the curriculum is on controlling driving rather than controlling drinking to avoid future DUI convictions. The implementation of the program is ongoing throughout the state of Florida. The current randomized study focused on intermediate outcomes relevant for DUI recidivism; specifically, individuals' readiness for change regarding drinking and driving, and their endorsement of a PARC planning and action approach (controlling driving) versus a traditional approach (controlling drinking). The current research demonstrated that the PARC program is effective in moving participants toward more readiness for change and toward a strategy of planning ahead to avoid driving to any venue in which drinking may occur. Future research will assess the ultimate effect on DUI recidivism. 相似文献
998.
Stam MR Danchin EG Rancurel C Coutinho PM Henrissat B 《Protein engineering, design & selection : PEDS》2006,19(12):555-562
Family GH13, also known as the alpha-amylase family, is the largest sequence-based family of glycoside hydrolases and groups together a number of different enzyme activities and substrate specificities acting on alpha-glycosidic bonds. This polyspecificity results in the fact that the simple membership of this family cannot be used for the prediction of gene function based on sequence alone. In order to establish robust groups that show an improved correlation between sequence and enzymatic specificity, we have performed a large-scale analysis of 1691 family GH13 sequences by combining clustering, similarity search and phylogenetic methods. About 80% of the sequences could be reliably classified into 35 subfamilies. Most subfamilies appear monofunctional (i.e. contain enzymes with the same substrate and the same product). The close examination of the other, apparently polyspecific, subfamilies revealed that they actually group together enzymes with strongly related (or even sometimes virtually identical) activities. Overall our subfamily assignment allows to set the limits for genomic function prediction on this large family of biologically and industrially important enzymes. 相似文献
999.
Olivier Lavigne Catherine Alemany-Dumont Bernard Normand Sandrine Berthon-Fabry Rudolf Metkemeijer 《International Journal of Hydrogen Energy》2012
In this paper, two types of chromium PVD coatings (100 nm) have been elaborated on 316L stainless steel (SS) by adjusting the nitrogen flow rate. The first coating is a mixture of Cr2N and Cr, the second one is a single phase CrN. It is shown that the performances of the material are strongly dependant of the nature of the passive film formed on the chromium nitride layers due to the galvanic coupling between the coating and the substrate. The CrN coated SS shows very good corrosion resistance in simulated PEMFC media. The surface conductivity of the SS is also greatly improved and the CrN coated SS shows an interfacial contact resistance of 10 mΩ cm2 at 140 N cm−2. Five single cells of stainless steel bipolar plates coated with the CrN film were assembled for performance test. This 5 cell stack does not show any mean voltage degradation over 200 h dynamic cycling. Moreover, the performances of the CrN coated SS bipolar plates are very close to the Au-coated SS bipolar plates. 相似文献