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151.
Walter Ried Harald Knorr Gerilard Oremek 《Advanced Synthesis \u0026amp; Catalysis》1978,320(2):246-248
Reactions of Cyclobutendiones. LII. Reaction of 4-Hydroxy-3-phenyl-3-cyclobuten-1-ones with Arylhydrazines In the reaction of hydroxycyclobutenones of the typ 1 – 4 with arylhydrazines 5 an unexpected reaction behaviour is found. The major products are hydrazones of different structure, the well known hydroxy-cyclopropane-carboxylicacid hydrazines 6 [1] are byproducts. The direction of the reaction depends on the substituents X, on the different substituted arylhydrazines and the solvents. 相似文献
152.
153.
Weiqiang Li Jerry L. Jensen Walter B. Ayers Stephen M. Hubbard M. Reza Heidari 《Journal of Petroleum Science and Engineering》2009,68(3-4):180-186
Reservoir connectivity is often an important consideration for reservoir management. For example, connectivity controls waterflood sweep efficiency and it affects decisions concerning well placement and spacing. The uncertainty of sandbody distributions, however, can make interwell connectivity prediction extremely difficult. Percolation models are a useful tool to simulate sandbody connectivity behavior to estimate interwell connectivity.This study applies a percolation method to estimate interwell connectivity. Using results derived by Andrade, King, and others for fluid travel time between locations in a percolation model, we develop a method to estimate interwell connectivity. Four parameters are needed to use this approach: the net-to-gross ratio psand, the typical sandbody size, reservoir length and well spacing. To evaluate this new percolation method, the results are compared to results from geometrical models, Monte Carlo, and reservoir simulation.These methods were applied to estimate interwell connectivity for three non-communicating stratigraphic intervals in Monument Butte oil field, Utah. The results suggest that the percolation method can estimate the probability of interwell connectivity reliably for thin intervals for any values of psand, well spacing, and reservoir length. The geometrical model also performs well, but can only be applied in fields where the well spacing is less than one-half of the sandbody size.The proposed method requires that the reservoir interval for evaluation be sufficiently thin so that 2D percolation results can be applied. For thick intervals or heterogeneous sandbody distributions, the percolation method developed here is not suitable because it assumes thin layers. Future percolation research will be needed to adapt this new method to 3D cases. 相似文献
154.
155.
Multi-criteria location planning for public facilities in tsunami-prone coastal areas 总被引:3,自引:0,他引:3
We present a model for multi-objective decision analysis with respect to the location of public facilities as schools in areas
near to coasts, taking risks of inundation by tsunamis into account. A mathematical programming formulation with three objective
functions is given. The first objective function is a weighted mean of a minisum and a maximum coverage criterion. The second
objective function expresses risk by possible tsunami events; for quantifying this risk, a statistical model for tsunami occurrences
by Kaistrenko and Pinegina is applied. The third criterion represents costs. For the solution of the multi-objective optimization
problem, we propose a heuristic approach based on the NSGA-II algorithm and compare it with a decomposition technique where
the region under consideration is partitioned into smaller sub-regions, and the problem is solved for each separate subregion
either exactly or heuristically. Both approaches are tested on two real-life instances from southern Sri Lanka. 相似文献
156.
Kirsten Bobzin Nazlim Bagcivan Arnold Gillner Claudia Hartmann Jens Holtkamp Walter Michaeli Fritz Klaiber Maximilian Sch?ngart Sebastian Thei? 《Production Engineering》2011,5(4):415-422
Molding of micro structures by injection molding leads to special requirements for the molds e.g. regarding wear resistance
and low release forces of the molded components. At the same time it is not allowed to affect the replication precision. Physical
vapor deposition (PVD) is one of the promising technologies for applying coatings with adapted properties like high hardness,
low roughness, low Young’s modulus and less adhesion to the melt of polymers. Physical vapor deposition technology allows
the deposition of thin films on micro structures. Therefore, the influence of these PVD layers on the contour accuracy of
the replicated micro structures has to be investigated. For this purpose injection mold inserts were laser structured with
micro structures of different sizes and afterwards coated with two different coatings, which were deposited by a magnetron
sputter ion plating PVD technology. After deposition, the coatings were analyzed by techniques regarding hardness, Young’s
modulus and morphology. The geometries of the micro structures were analyzed by scanning electron microscopy before and after
coating. Afterwards, the coated mold inserts were used for injection molding experiments. During the injection molding process,
a conventional and a variothermal temperature control of the molds were used. The molded parts were analyzed regarding roughness,
structure height and structure width by means of laser microscopy. 相似文献
157.
158.
Adriano G. Cruz Eduardo H.M. Walter Rafael Silva Cadena José A.F. Faria Helena M.A. Bolini Hidelte P. Pinheiro Anderson S. Sant’Ana 《Food research international (Ottawa, Ont.)》2010,43(5):1444-1448
The feasibility of survival analysis methodology was used to determine the shelf-life of probiotic strawberry flavored yogurt supplemented with Bifidobacteirum animalis DN 173010 W was investigated. The quality parameters of probiotic yogurts were related to storage conditions which they are submitted. The consumers were shown sensitive to changes towards sensory characteristics introduced into the products. Using the survival analysis and considering 25% and 50% probability of consumer rejection, the shelf-life of the probiotic yogurt was estimated at 38 and 53 days, respectively. The findings of this research highlighted the feasibility this technique to determine the shelf-life of foods, in particular, functional foods, as probiotic yogurts. 相似文献
159.
Fabien Belmonte Walter SchönLaurent Heurley Robert Capel 《Reliability Engineering & System Safety》2011,96(2):237-249
This paper presents an application of functional resonance accident models (FRAM) for the safety analysis of complex socio-technological systems, i.e. systems which include not only technological, but also human and organizational components. The supervision of certain industrial domains provides a good example of such systems, because although more and more actions for piloting installations are now automatized, there always remains a decision level (at least in the management of degraded modes) involving human behavior and organizations. The field of application of the study presented here is railway traffic supervision, using modern automatic train supervision (ATS) systems. Examples taken from railway traffic supervision illustrate the principal advantage of FRAM in comparison to classical safety analysis models, i.e. their ability to take into account technical as well as human and organizational aspects within a single model, thus allowing a true multidisciplinary cooperation between specialists from the different domains involved.A FRAM analysis is used to interpret experimental results obtained from a real ATS system linked to a railway simulator that places operators (experimental subjects) in simulated situations involving incidents. The first results show a significant dispersion in performances among different operators when detecting incidents. Some subsequent work in progress aims to make these “performance conditions” more homogeneous, mainly by ergonomic modifications. It is clear that the current human-machine interface (HMI) in ATS systems (a legacy of past technologies that used LED displays) has reached its limits and needs to be improved, for example, by highlighting the most pertinent information for a given situation (and, conversely, by removing irrelevant information likely to distract operators). 相似文献
160.
Walter Fumy 《Datenschutz und Datensicherheit - DuD》2011,35(1):16-21
Die International Civil Aviation Organization (ICAO) spielt eine zentrale Rolle bei der Entwicklung von Spezifikationen für
Reisep?sse und andere Reisedokumente. ICAO-Standards für Dokumentenformate und -inhalte erleichtern internationales Reisen
und verbessern die nationale Sicherheit, indem sie die Grenzkontrollbeh?rden in die Lage versetzen, die Gültigkeit von Reisedokumenten
schneller und vor allem zuverl?ssiger zu prüfen. Die Spezifikationen der Sicherheitsmerkmale für von den EU-Mitgliedstaaten
ausgestellte Reisep?sse und Reisedokumente bauen auf diesen ICAO-Standards auf. 相似文献