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101.
As part of the ERDA Division of Magnetic Fusion Energy effort to achieve fusion power by the end of the century, superconducting magnet programs were established at several of the national laboratories with the support of numerous industries. Recently, these program goals have been reviewed and modified to reflect new directions in fusion research. The development of superconducting toroidal field coils has been assigned first priority for the Experimental Power Reactor. This effort, centered at ORNL, will have the extensive support of industry, so that large construction capability can be encouraged. Ohmic heating coils for tokamaks promise to be an even more difficult task, and an expanded effort will be initiated as funds become available. Magnets for mirror confinement systems should have the highest fields practical. Accordingly, LLL has been funded to develop multifilamentary niobium-tin for future might experiments. If successful, the material might complement the recent trend toward higher field tokamaks as well. Energy Storage development at LASL is concentrating on inductive storage for 1 msec discharge and a superconducting homopolar generator for 30 msec to 1 sec discharge times. The stainless steel structure is a major cost element of any magnet system. However, recent calculations have shown that a magnetic coil form affects the toroidal field ripple in the EPR by only a few parts in a thousand. Thus, an opportunity exists to characterize and develop less expensive alloys for low temperature magnet structures. 相似文献
102.
In this paper we propose a new model for estimating the effective properties of regular hexagonal honeycombs. This model yields some new simple formulae which, in contrast to previous attempts, match the general invariant relations found by Vigdergauz in 1999. By comparing with numerical results, we also find some improved (but still simple) formulae which enable us to estimate the effective properties with an accuracy better than 1%, even for high density honeycombs. 相似文献
103.
Thomas Finke Dominic Lingenfelser Katharina Bindler Ulrich Eisele Henning Bockhorn Gunther Brunklaus 《Journal of the American Ceramic Society》2009,92(8):1823-1830
This paper deals with the specific interaction of the dispersant 3,6,9-trioxadecanoic acid (TODA) with nano-ZrO2 surfaces. Special interest was directed towards degradation behavior of the adsorbates and its influence on dispersant capabilities of TODA regarding stabilization of ethanolic nano-ZrO2 suspensions. ZrO2 adsorption sites and the adsorbates formed are examined by diffuse reflectance infrared Fourier transform spectroscopy, thermal analysis, 1 H-, and 13 C-cross polarization magic angle spinning solid-state nuclear magnetic resonance spectroscopy. 1 H as well as 13 C-chemical shifts and the configurations of the corresponding adsorbed TODA species on zirconia sites are predicted by means of density functional theory quantum chemical calculations for supporting the interpretation of the experimental spectral data obtained. This work shows that combination of analytical and theoretical methods is an effective approach characterizing surface chemical properties of ceramic materials, determining sorption properties of organic process additives, investigating correspondent elementary and degradation reactions as well as clarifying cause-effect relationships in ceramic processes. 相似文献
104.
105.
Ozan Gürbüz Duygu Göçmen Fatih Dagˇdelen Murat Gürsoy Sami Aydin İsmet Şahin Levent Büyükuysal Mehmet Usta 《Food chemistry》2007,100(2):518-525
Concentrations of trans-resveratrol, catechin and epicatechin were analyzed in musts and wines produced from seven red and four white grape cultivars from various wine growing regions of Turkey. Phenolics were quantified using an HPLC method optimized for the separation of wine phenolics. Wine samples contained higher phenolics levels than the corresponding musts. With the exception of Semillion, white wines and musts contained lower concentrations of phenolics than red wines and musts. However, the white cultivar Semillion had the highest concentrations of catechin and epicatechin among all wine and must samples. Semillion wine catechin and epicatechin were 13.7 and 11.8 mg/L, respectively. The highest level of trans-resveratrol among the white cultivars was found in Narince wine (1.93 mg/L). Within the red wine and must cultivars, Bo?azkere, Öküzgozü, and Cabernet contained the highest concentrations of flavan-3-ols and trans-resveratrol. Catechin was the major phenolic in all wines and most musts. Epicatechin was the major phenolic in 6 of the 11 must samples, but none of the wine samples. trans-Resveratrol was generally found in lowest concentrations in both wines and musts. 相似文献
106.
Suzelotte Kruijver Lie Zhao Jilt Sietsma Erik Offerman Niels van Dijk Lawrence Margulies Erik Lauridsen Stephan Grigull Henning Poulsen Sybrand van der Zwaag 《国际钢铁研究》2002,73(6-7):236-241
In‐situ deformation tests have been performed on a steel displaying the transformation‐induced plasticity (TRIP) effect, while monitoring the phase transformation by means of X‐ray diffraction. A tensile stress is applied to 0.4 mm thick samples of this steel with mass contents of 0.26 % Si, 1.5 % Mn, and 1.8 % Al in a transmission geometry for a synchrotron‐radiation beam of 25 μm · 25 μm. On the diffraction patterns every grain appears as a discrete spot. The austenite {200} reflections are analysed during this investigation. The diffraction patterns are treated like a powder pattern for five different η‐angles, with η representing the angle between the tensile direction and the normal direction of the diffracting {200} planes. The results of the analysis show that η = 0° and η = 90° are the preferential orientations for the transformation to martensite. The Ludwigson and Burger model [9] is used to gain more information about the stress dependence of the deformation induced martensite formation. The microdiffraction patterns also reveal the changes in carbon concentration in austenite at each retained austenite fraction. 相似文献
107.
Johan P. Hansen Henning Stichtenoth 《Applicable Algebra in Engineering, Communication and Computing》1990,1(1):67-77
We construct a series of algebraic geometric codes using a class of curves which have many rational points. We obtain codes of lengthq
2 over
q
, whereq = 2q
0
2
andq
0 = 2
n
, such that dimension + minimal distance q
2
+ 1 – q
0
(q – 1). The codes are ideals in the group algebra
q
[S], whereS is a Sylow-2-subgroup of orderq
2 of the Suzuki-group of orderq
2
(q
2
+ 1)(q – 1). The curves used for construction have in relation to their genera the maximal number of
GF
q
-rational points. This maximal number is determined by the explicit formulas of Weil and is effectively smaller than the Hasse—Weil bound.Supported by Deutsche Forschungsgemeinschaft while visiting Essen University 相似文献
108.
Werner Strohmaier Henning Klostermeyer Paul Deuritz Erich Windhab 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1992,194(6):531-535
Summary Current texture-measuring instruments and a recently developed measuring method (two-dimensional measuring of the force necessary to spread a sample) were compared in measuring the spreadability of processed cheese. How far subjective assessment by a qualified panel correlates with the instrumental results in determining spreadability and firmness was also investigated. Samples of processed cheese with various consistencies were measured by an Universal testing machine, a buttermeasuring instrument (DIN 10331), a rotational-type rheometer (oscillation mode) and a two-dimensional force measuring instrument. The evaluation of the results shows that an oscillating rheometer is most suitable to measure the spreadability of processed cheese; the correlation coefficient (r) between the dynamic Weissenberg number, calculated from parameters of the rheometer, and the subjective judgement by the panel wasr=0.91. For the determination of firmness the two-dimensional force measuring instrument is most suitable. The correlation coefficient between the parameter tangential energy (S
t) and the sensorially evaluated firmness wasr=0.95.
Vergleich verschiedener Bestimmungsmethoden für die Streichfähigkeit und Festigkeit von Schmelzkäse
Zusammenfassung Verschiedene gebräuchliche Meßinstrumente und ein neu entwickeltes Gerät zur zweidimensionalen Messung der Kräfte, die zum Ausstreichen einer Probe erforderlich sind, wurden vergleichend zur Charakterisierung der Streichfähigkeit von Schmelzkäse erprobt. Dabei wurde auch geprüft, inwieweit die subjektiven Beurteilungen eines qualifizierten Prüferpanels mit den Meßwerten für Streichfähigkeit und Festigkeit korrelierten. Gemessen wurde mit einer Universalprüfmaschine, dem Butterprüfgerät (DIN 10331), einem Rotationsrheometer und mit dem zweidimensional registrierenden Kraftmeßgerät. Dabei zeigte sich, daß das Rheometer im oscillierenden Modus die Streichfähigkeit am besten zu charakterisieren vermag. Die Korrelation zwischen den Rheometerwerten, berechnet als dynamische Weissenbergzahl, und den sensorisch ermittelten Werten für die Streichfähigkeit betrugr=0,91. Zur Bestimmung der Festigkeit ist das zweidimensional registrierende Kraftmeßgerät am besten geeignet, was sich in einem Korrelationskoeffizienten vonr=0,95 zwischen dem ParameterS t und den im Sensoriktest ermittelten Werten für dieFestigkeit ausdrückt.相似文献
109.
Brandon Henning GE Fanuc 《软件》2009,(1):41-42
新型控制系统平台帮助糖类产品生产商,根据变化的市场需要,最优化食用糖和纯乙醇的混合生产过程。 相似文献
110.
Seeger Dag Halvorsen John-Bjarne Hansen Sameline Grimsgaard Kaare H. Bønaa Peter Kierulf Arne Nordøy 《Lipids》1997,32(9):935-942
The n-3 fatty acids (FA) from marine sources are known to exert antiinflammatory effects on monocyte function. There is still
controversy whether n-3 FA may increase the susceptibility to infections. The present study was designed to assess the effect
of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHa) on monocyte phagocytosis and respiratory burst activity. Fifty-eight
healthy men were randomized to take a daily supplement of 3.8 g highly purified EPA (n=20), 3.6 g DHA (n=19), or corn oil (n=19) for 7 wk. Mononuclear leukocytes were collected, isolated, and cryopreserved prior to and after dietary supplementation.
Paired samples were analyzed in the presence of autologous serum in a crossover design. Monocyte phagocytosis and respiratory
burst activity were measured by flow cytometry after ingestion of Escherichia coli. Monocytes retained their phagocytic ability and respiratory burst activity after supplementation. No reduction in internalization
of bacteria was registered. Dietary n-3 FA and particularly EPA improved bacterial adherence to the monocyte surface. In the
crossover experiments, there was an adverse effect of serum enriched with n-3 FA on bacterial adherence. We conclude that
monocytes retain their phagocytic potential after supplementation with purified EPA and DHA. 相似文献