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81.
Polina Vakuliuk Anatoliy Burban Victorya Konovalova Mihailo Bryk Marina Vortman Nina Klymenko Valeriy Shevchenko 《Desalination》2009,235(1-3):160-169
Microbiological contamination of polymeric membranes in the process of their exploitation is an essential problem of membrane technology. It results in the increase of manufacturing costs, destruction of membranes, operating life reduction and secondary contamination of water by the metabolism products of microorganisms. For the purpose of reduction of membrane biofouling and biodegradation investigation of adsorption of the guanidine containing oligomers on the surface of PET track membranes was conducted and their influence on the selectivity and antibacterial properties of the membranes was investigated. It was established that modified membranes have substantially higher resistance to biofouling. 相似文献
82.
83.
Water Concession Principles for Geothermal Aquifers in the Mura-Zala Basin,NE Slovenia 总被引:1,自引:0,他引:1
Demand for thermal water in the Mura-Zala basin, situated between Slovenia, Austria, Hungary and Croatia, is constantly increasing, with the sandy geothermal aquifer within the Neogene Mura formation being the most exploited. During the water concession granting process various problems were identified, together with the need for elaboration of the uniform concession granting principles. The latter were devised according to the specific hydrogeological settings and field inspection of 23 geothermal wells, performed through use of an adapted methodology. The inspection revealed changes in wells performance, low efficiency of energy abstraction and a lack of reinjection. The acquired information was applied to the development of particular principles, including the six key indicators. Firstly, a unified and integrated operational monitoring programme must be established, and upgraded by a national surveillance monitoring. Secondly, an application of the best available techniques is proposed. Stimulation of energetic and balneology efficiency is also needed, with recharge and reinjection conditions evaluated and applied where possible. Limited or full water concessions could be granted based on their fulfilment then. This continuous step-by-step approach should enable the implementation of adequate measures to meet the standards required for the thermal groundwater bodies according to the EU water framework directions. 相似文献
84.
Measured the effectiveness of A. P. Goldstein's (1973) Structured Learning Training (SLT) for teaching confrontation skills to 56 trainees varying in conceptual development (Paragraph Completion Test). Both a self-instruction approach and a standard implementation of SLT were effective for teaching confrontation skills. When trainees' conceptual level (CL) was considered, the approaches proved differentially effective (as measured by pencil-and-paper tests). Self-instruction SLT was more effective with high CL trainees than with low CL trainees; guided-instruction SLT proved more effective than self-instruction SLT with low CL trainees in each treatment. Further, differences due to instructional approach and CL failed to reach significance when the dependent variable was assessed via taped role play. Findings suggest the need for multiple ways of assessing skills as well as multiple approaches for instruction. Further investigation seems necessary to specify the variables involved in maximizing the effect of instruction. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
蔡妮娜 《艺术与设计.数码设计》2007,(1)
本文通过对品牌战略和文化及其二者关系的分析来说明文化的介入在企业竞争中所起到的重要作用。文化的介入使品牌战略更具包容力,使企业更具凝聚力和竞争力。只有依靠优秀的文化,企业才能像常青藤一样生机盎然、充满活力。 相似文献
86.
Frese Michael; Krauss Stefanie I.; Keith Nina; Escher Susanne; Grabarkiewicz Rafal; Luneng Siv Tonje; Heers Constanze; Unger Jens; Friedrich Christian 《Canadian Metallurgical Quarterly》2007,92(6):1481
A model of business success was developed with motivational resources (locus of control, self-efficacy, achievement motivation, and self-reported personal initiative) and cognitive resources (cognitive ability and human capital) as independent variables, business owners' elaborate and proactive planning as a mediator, and business size and growth as dependent variables. Three studies with a total of 408 African micro and small-scale business owners were conducted in South Africa, Zimbabwe, and Namibia. Structural equation analyses partially supported the hypotheses on the importance of psychological planning by the business owners. Elaborate and proactive planning was substantially related to business size and to an external evaluation of business success and was a (partial) mediator for the relationship between cognitive resources and business success. The model carries important implications for selection, training, and coaching of business owners. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
Nina P.G. Salau Gustavo Alberto Neumann Jorge O. Trierweiler Argimiro R. Secchi 《Journal of Process Control》2009,19(3):530-538
In an industrial gas-phase polyethylene reactor, the safe operating range of temperature is rather narrow. Even within this temperature range, temperature excursions must be avoided because they can result in low catalyst productivity and significant changes in product properties. If the manipulated variable for temperature control saturates (i.e., the cooling water valve position is completely open), then the reactor operates without a feedback temperature controller, leading to oscillatory behavior and limit cycles. In this work, it has been demonstrated that the saturation in the manipulated variable and the complex non-linear dynamic behavior are removed when auxiliary manipulated variables, obtained by bifurcation analysis, are used in a multivariable control strategy for the reactor temperature control. Two control structures are proposed and compared considering their impact in the reactor production and polymer melt index. In the first control structure, the designed PID controller for the reactor temperature is considered and a switching strategy with a PI controller for the auxiliary manipulated variables is included. In the second control structure, the designed PID controller for the reactor temperature is also used, however, a MPC controller for the auxiliary manipulated variables is considered. The results suggest that the use of gain-scheduling strategy in the PID temperature controller with a MPC controller for the auxiliary manipulated variables avoids the saturation of the manipulated variable and, hence, the undesired non-linear dynamic behavior, reducing the production loss and improving the product quality. 相似文献
88.
Kseniya Khamina Andreas B. Diendorfer Susanna Skalicky Moritz Weigl Marianne Pultar Teresa L. Krammer Catharine Aquino Fournier Amy L. Schofield Carolin Otto Aaron Thomas Smith Nina Buchtele Christian Schoergenhofer Bernd Jilma Bernhard J. H. Frank Jochen G. Hofstaetter Regina Grillari Johannes Grillari Klemens Ruprecht Christopher E. Goldring Hubert Rehrauer Warren E. Glaab Matthias Hackl 《International journal of molecular sciences》2022,23(3)
89.
Physiological and pathological vascular responses depend on the action of numerous intercellular mediators, ranging from hormones to gases like nitric oxide, proteins, and lipids. The last group consists not only of the different types of lipoproteins, but also includes a broad array of other lipophilic signaling molecules such as fatty acids, eicosanoids, phospholipids and their derivatives, sphingolipids and isoprenoids. Due to space limitations, it is impossible to discuss all the vascular effects of lipophilic mediators or compounds. Therefore, we will focus on one of the most important lipid-mediated diseases, atherosclerosis. Lipoproteins and especially their native or oxidized lipid compounds affect vascular function in many different ways, and these effects do not only modulate atherogenesis but are of paramount physiological and pathophysiological importance in other diseases, such as inflammation, tumor metastasis, or normal wound healing. 相似文献
90.
Thora Tenbrink Robert J. Ross Kavita E. Thomas Nina Dethlefs Elena Andonova 《Journal of Visual Languages and Computing》2010,21(5):292-309
When conveying information about spatial situations and goals, speakers adapt flexibly to their addressee in order to reach the communicative goal efficiently and effortlessly. Our aim is to equip a dialogue system with the abilities required for such a natural, adaptive dialogue. In this paper we investigate the strategies people use to convey route information in relation to a map by presenting two parallel studies involving human–human and human–computer interaction. We compare the instructions given to a human interaction partner with those given to a dialogue system which reacts by basic verbal responses and dynamic visualization of the route in the map. The language produced by human route givers is analyzed with respect to a range of communicative as well as cognitively crucial features, particularly perspective choice and references to locations across levels of granularity. Results reveal that speakers produce systematically different instructions with respect to these features, depending on the nature of the interaction partner, human or dialogue system. Our further analysis of clarification and reference resolution strategies produced by human route followers provides insights into dialogue strategies that future systems should be equipped with. 相似文献