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51.
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Jewgenij Botaschanjan Manfred Broy Alexander Gruler Alexander Harhurin Steffen Knapp Leonid Kof Wolfgang Paul Maria Spichkova 《Formal Aspects of Computing》2008,20(6):637-662
Formal verification of software systems is a challenge that is particularly important in the area of safety-critical automotive systems. Here, approaches like direct code verification are far too complicated, unless the verification is restricted to small textbook examples. Furthermore, the verification of application logic is of limited use in industrial context, unless the underlying operating system and the hardware are verified, too. This paper introduces a generic model stack, allowing the verification of all system layers as well as the concrete application models being used in the upper layers. The presented models and proofs close the gap between the correctness proof for the lower layers of car electronics developed at the Saarland University and the verification procedure for distributed applications developed at the Technische Universität München. 相似文献
53.
Enhancing crop yield with the use of N‐based fertilizers co‐applied with plant hormones or growth regulators 下载免费PDF全文
Leonid V Kurepin Warwick Catto Richard P Pharis 《Journal of the science of food and agriculture》2015,95(9):1777-1785
Crop yield, vegetative or reproductive, depends on access to an adequate supply of essential mineral nutrients. At the same time, a crop plant's growth and development, and thus yield, also depend on in situ production of plant hormones. Thus optimizing mineral nutrition and providing supplemental hormones are two mechanisms for gaining appreciable yield increases. Optimizing the mineral nutrient supply is a common and accepted agricultural practice, but the co‐application of nitrogen‐based fertilizers with plant hormones or plant growth regulators is relatively uncommon. Our review discusses possible uses of plant hormones (gibberellins, auxins, cytokinins, abscisic acid and ethylene) and specific growth regulators (glycine betaine and polyamines) to enhance and optimize crop yield when co‐applied with nitrogen‐based fertilizers. We conclude that use of growth‐active gibberellins, together with a nitrogen‐based fertilizer, can result in appreciable and significant additive increases in shoot dry biomass of crops, including forage crops growing under low‐temperature conditions. There may also be a potential for use of an auxin or cytokinin, together with a nitrogen‐based fertilizer, for obtaining additive increases in dry shoot biomass and/or reproductive yield. Further research, though, is needed to determine the potential of co‐application of nitrogen‐based fertilizers with abscisic acid, ethylene and other growth regulators. © 2014 Society of Chemical Industry 相似文献
54.
Jeyasankar Alagarmalai David Nestel Daniela Dragushich Ester Nemny-Lavy Leonid Anshelevich Anat Zada Victoria Soroker 《Journal of chemical ecology》2009,35(5):542-551
The Ethiopian fruit fly, Dacus ciliatus, is an oligophagous pest of cucurbit crops, particularly melons, cucumbers, and marrows (summer squash). The present study
aimed to identify host attractants for D. ciliatus and was guided by a behavioral bioassay and an electrophysiological assay. We tested volatile compounds from the fruits of
a host plant, ripe and unripe Galia melon, Cucumis melo var. reticulates. Both sexes were attracted to melon volatiles. Those of ripe melon were preferred. Gas chromatography-electroantennographic
detection analysis of the behaviorally active ripe melon volatiles consistently showed that 14 compounds elicited similar
antennal responses from both sexes. Twelve compounds were identified by gas chromatography-mass spectrometry (GC-MS) using
GC-MS libraries, retention indices (RI), and authentic standards. The electrophysiological activities of the compounds that
were present at sufficient levels for identification, benzyl acetate, hexanyl acetate, (Z)-3-hexenyl acetate, (Z)-3-octenyl acetate, octanyl acetate, (Z)-3-decenyl acetate, and (E)-β-farnesene, were evaluated at six different dosage levels by using electroantennography (EAG). Benzyl and hexanyl acetates
elicited dose responses only in males, while other tested compounds elicited dose responses in both sexes. The strongest responses
were observed for doses between 100 ng and 10 μg. The dose response, in terms of attractiveness to synthetic compounds within
the active range (as determined by EAG), also was evaluated in the behavioral bioassay. Synthetic acetates were attractive
to both sexes when tested individually. Significant attraction was observed when individual compounds were applied in the
bioassay arena at doses of 0.5–1 μg/dispenser. Blends of compounds in equal proportions also were attractive to the insects.
The most attractive blend was a mixture of four or five identified acetates. The addition of an equal proportion of (E)-β-farnesene to this mixture had a deterrent effect. 相似文献
55.
The method of self-burial of radioactive waste in geological formations using direct heating of rocks by radiation is proposed in this paper. In the currently known studies, thermal conductivity is considered as a main heat transfer mechanism. Application of high penetrating gamma radiation for direct melting of surrounding rocks will reduce the energy absorption inside the sinking device and will lower maximum temperature and temperature gradients in the elements of the device. In this paper, conditions of realization of the direct heating by radiation mechanism are presented and requirements to heat-generating radionuclides have been derived. Assessments of the spatial distribution of energy release in the surrounding rocks for the point and plane sources with the radionuclide 60Co have been performed. Based on these data, the temperature distributions in the surrounding rocks and the expression for determining the descent velocity as a function of 60Co surface activity in the sinking device have been obtained. Estimations of energy absorption fraction inside the spherical heat-generating elements filled with 60Co and surface activity of 60Co, necessary to achieve velocity of about 1 km per year, have been made. The results are given for granite and salt rocks. 相似文献
56.
57.
Leonid M. Drabkin 《Renewable Energy》1998,13(2):269-272
In this paper we present thermodynamic analysis of the heat pump with solar steam and gas turbines. 相似文献
58.
Photo-thermo-refractive (PTR) glass demonstrates refractive index change after exposure to UV radiation followed by a thermal treatment that enables recording of high efficiency holographic optical elements. This work demonstrates feasibility of function of this material as a complex optical medium which posseses both photosensitive and luminescent properties and paves a way for creation of monolythic solid state lasers where resonator components can be holographically recorded inside of a laser medium. It was found, that incorporating of Nd3+ ions in PTR glass does not affect photosensitivity required for hologram recording. It was demonstrated that emission wavelength, spectral width, and cross section of Nd3+ luminescence in PTR glass are typical for silicate laser glasses and Nd-doped PTR glass can be considered as a promising laser medium for monolithic solid state lasers. 相似文献
59.
A new analytical approach for retrieval of the vertically weighted chlorophyll a concentration (Chl(rs)) detected by remote sensors is presented. Model calculations were carried out for the turbid waters of Lake Kinneret, Israel, and showed that Chl(rs) may be replaced by the average chlorophyll a concentration (Chl(p)) within the upper "penetration layer" 0-Z(p). The study also showed a high correlation between Chl(rs) and Chl concentration averaged in the other depth layers, namely, the 0-1 m layer, the euphotic layer (0-Z(e)), and the production layer (0-Z(pr)). Our findings are closely related to models developed for the world ocean, with the exception of periods when the dinoflagellate Peridinium gatunense blooms in the lake. We showed the effect of the pattern of vertical Chl distributions within the penetration layer on the difference between Chl(rs) and other Chl indices was conspicuous when the Chl maximum was in the uppermost 0- m layer of the water column. We assume that the presented approaches are instrumental for further development of optimal, locally adapted algorithms for remote sensing of Chl in any type of natural waters. 相似文献
60.