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101.
Tharinger Deborah J.; Lambert Nadine M.; Bricklin Patricia M.; Feshbach Norma; Johnson Neal F.; Oakland Thomas D.; Paster Vera S.; Sanchez William 《Canadian Metallurgical Quarterly》1996,27(1):24
National, state, and local education reform agendas have been on a fast track for more than a decade. Although some psychologists have been active in promoting psychology and psychological services in education reform initiatives, knowledge about their efforts is fragmented. In order to educate psychologists about education reform, this article highlights the impetus for the recent education reform movement, briefly reviews the latest waves of education reform, and discusses the development of the National Education Goals. Then, an argument is made for the integration of education, health, and social reform initiatives; state-level education reform principles and initiatives are highlighted, illustrated by the systemic education reform mandate in Kentucky. Next, progress toward the development and implementation of an APA-sponsored response to the National Education Goals is discussed. Finally, objectives and roles for psychologists in advancing education reform are presented, and guidelines for the education and training of future psychologists are introduced. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
MARKTRAN II is an interactive FORTRAN IV program that computes Markov transition probabilities for two-dimensional patterns. The pattern is represented by a series of discrete states at each point on a rectangular grid composed of square cells. Transition probabilities in eight directions are computed. MARKTRAN II is useful for numerically describing the fabric of patterns that possess any degree of anisotropy. Geological applications include analysis of rock fabrics, outcrop patterns of geological maps, and variations in ore grade expressed as discrete states. 相似文献
103.
Kenneth W. Neves 《Computer Physics Communications》1982,26(3-4):303-310
The principles of vector computation are reviewed including a definition of “depth of parallelism”. The latter concept is related to algorithm performance on various computer architectures (in particular the CRAY-1 and the FPS AP120B). The challenge of providing efficient mathematical software libraries on vector computers and the subsequent trade-offs introduced by vector architecture are discussed. Boeng's multi-level library approach to meet vector computer user's needs is explained. Some timing comparisons for software on the CRAY-1 are also given. 相似文献
104.
Steuer S Pingoud V Pingoud A Wende W 《Chembiochem : a European journal of chemical biology》2004,5(2):206-213
Homing endonucleases are extremely specific endodeoxyribonucleases. In vivo, these enzymes confer mobility on their genes by inducing a very specific double-strand cut in cognate alleles that lack the cooling sequence for the homing endonuclease; the cellular repair of the double-strand break with the endonuclease-containing allele as a template leads to integration of the endonuclease gene, completing the homing process. As a result of their extreme sequence specificity, homing endonucleases are promising tools for genome engineering. For this purpose, it is desirable to design enzymes with defined new specificities. To analyse which DNA-binding elements are potential candidates for use in the design of enzymes with modified or even new specificity, we produced several chimeric proteins derived from the Saccharomyces cerevisiae VMA1 intein (PI-SceI) and the related Candida tropicalis VMA1 intein. Although the mature Candida intein is devoid of endonucleolytic activity, the exchange of two DNA-binding modules of PI-SceI with the homologous elements from the Candida intein results in an active endonuclease. The low sequence homology in these modules indicates that different protein-DNA contacts are responsible for the recognition of related DNA sequences. This flexibility in DNA recognition should, in principle, allow endonucleases to be produced with new specificities useful for genome engineering. 相似文献
105.
106.
Khoruzhaya Vera G. Meleshevich Konstantin A. 《Powder Metallurgy and Metal Ceramics》2003,42(5-6):268-273
Phase equilibria in the ternary system Mg – Al – Ca in the composition range 50-100 mass% Mg were studied by the methods of differential thermal, xray diffraction, electron-probe and microscopic analysis. The projection of the liquidus surface on the concentration triangle, isothermal section at 150°C and polythermal sections at 4.5, 8.5, and 16 mass% Al were constructed. It was determined that additions of Al and Ca decrease the liquidus temperature of magnesium alloys (from 650 to 438°C). It is shown that the three-phase region + 2Ca> + 17Al12> exists at 150°C with the corresponding two-phase fields. The temperature dependence of the homogeneity range of the Mgbased solid solution was determined, and also the temperatures of the phase transformations which occur in the investigated range of compositions in the system. 相似文献
107.
do Lago CL da Silva HD Neves CA Brito-Neto JG da Silva JA 《Analytical chemistry》2003,75(15):3853-3858
A new microfabrication process based on a xerographic process is described. A laser printer is used to selectively deposit toner on a polyester film, which is subsequently laminated against another polyester film. The toner layer binds the two polyester films and allows the blank regions to become channels for microfluidics. These software-outlined channels are approximately 6 microm deep. Approximately twice this depth is obtained by laminating two printed films. The resulting devices were not significantly damaged after 24 h of exposure to aqueous solutions of H3PO4, NaOH, methanol, acetonitrile, or sodium dodecyl sulfate. Electric tests with an impedance analyzer and microchannels filled with KCl solution demonstrated that (1) wide channels suffer from deformation of the top and bottom walls due to the lamination of the polyester films and (2) the toner walls are somewhat porous. Although these drawbacks limit the maximum width of a channel and the minimum distance between two channels, the process is an attractive option to other expensive, laborious, and time-consuming methods for microchannels fabrication. The process has been used to implement devices for electrospray tip and capillary electrophoresis with contactless conductivity detection. 相似文献
108.
Environmental stress and recovery: the geochemical record of human disturbance in New Bedford Harbor and Apponagansett Bay,Massachusetts (USA) 总被引:1,自引:0,他引:1
Latimer JS Boothman WS Pesch CE Chmura GL Pospelova V Jayaraman S 《The Science of the total environment》2003,313(1-3):153-176
Sediments record the history of contamination to estuaries. Analysis of the concentrations of toxic organic compounds, contaminant and crustal metals, organic carbon content and isotopic composition in sediment cores from two estuarine systems in Buzzards Bay allowed reconstruction of human impacts over 350 years. Vertical distributions of the contaminants correlate with changes in the nature of watershed/estuarine activities. All contaminants were highly enriched (tens to hundreds times background) in modern New Bedford Harbor sediments. Enrichment began around the turn of the 20th century for all but PCBs, which were first synthesized in the 1930s. An increase in organic carbon content and a shift of carbon isotopes toward a more terrestrial signature illustrates increasing anthropogenic impact in New Bedford as population grew along with the industrial base. Institution of environmental protection measures in the late 20th century was reflected in decreased, although still substantially elevated, concentrations of contaminants. A lack of industrial development in Apponagansett Bay resulted in much lower concentrations of the same indicators, although specific contaminants related to the early whaling industry increased significantly above background as early as the late 18th century. The similarity of indicators in older portions of cores from NBH and unimpacted Apponagansett Bay demonstrates that cores can be used to establish reference conditions as successfully as using separate sites judged a priori to represent the reference state. The historical reconstruction approach provides the basis for establishing relationships between environmental stressors and factors that drive the stressors, as well as a framework for the assessment of ecological response(s) to environmental stressors over a range of time and/or exposure scales. 相似文献
109.
Vera Hollink Maarte van Someren Bob J Wielinga 《User Modeling and User-Adapted Interaction》2007,17(1-2):183-214
Users of web sites often do not know exactly which information they are looking for nor what the site has to offer. The purpose
of their interaction is not only to fulfill but also to articulate their information needs. In these cases users need to pass
through a series of pages before they can use the information that will eventually answer their questions. Current systems
that support navigation predict which pages are interesting for the users on the basis of commonalities in the contents or
the usage of the pages. They do not take into account the order in which the pages must be visited. In this paper we propose
a method to automatically divide the pages of a web site on the basis of user logs into sets of pages that correspond to navigation
stages. The method searches for an optimal number of stages and assigns each page to a stage. The stages can be used in combination
with the pages’ topics to give better recommendations or to structure or adapt the site. The resulting navigation structures
guide the users step by step through the site providing pages that do not only match the topic of the user’s search, but also
the current stage of the navigation process. 相似文献
110.
Francisco Andrade Paulo Novais José Machado José Neves 《Artificial Intelligence and Law》2007,15(4):357-373
The combined use of computers and telecommunications and the latest evolution in the field of Artificial Intelligence brought along new ways of contracting and of expressing will and declarations. The question is, how far we can go in considering computer intelligence and autonomy, how can we legally deal with a new form of electronic behaviour capable of autonomous action? In the field of contracting, through Intelligent Electronic Agents, there is an imperious need of analysing the question of expression of consent, and two main possibilities have been proposed: considering electronic devices as mere machines or tools, or considering electronic devices as legal persons. Another possibility that has been frequently mentioned consists in the application of the rules of agency to electronic transactions. Meanwhile, the question remains: would it possible, under a Civil Law framework, to apply the notions of “legal personhood” and “representation” to electronic agents? It is obvious that existing legal norms are not fit for such an endeavouring challenge. Yet, the virtual world exists and it requires a new but realistic legal approach on software agents, in order to enhance the use of electronic commerce in a global world. 相似文献