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971.
Ilaria Torre 《User Modeling and User-Adapted Interaction》2009,19(5):433-486
In this paper we provide a classification of adaptive systems with respect to the kind of semantic technology they exploit
to accomplish or improve specific adaptation and user modeling tasks. This classification is based on a distinction between
strong semantic techniques and weak semantic techniques. The former are techniques based on the Semantic Web, while the latter regard technologies that, in different ways, annotate
resources, enriching their meaning. This second category includes, in particular, Web 2.0 social annotations and mixed approaches
between social annotations and Semantic Web techniques. While the impact of the Semantic Web on adaptive systems has been
discussed in several survey papers, the potential of weak semantic technologies has, so far, received little attention. The
aim of this analysis is to fill this gap. Therefore, we will discuss contributions and limits of both approaches, but we will
focus special attention on weak semantic adaptive systems. 相似文献
972.
Keiko Miyabayashi Yasuhide Naito Mami Yamada Mikio Miyake Masaru Ushio Jun Fuchigami Ryuzo Kuroda Takashi Ida Kumi Hayashida Hisaya Ishihara 《Fuel Processing Technology》2008
Elemental compositions of components in feed and catalytically processed deasphalted oils were characterized by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The processed oils which were hydrocracked over a zeolite catalyst at three different reaction temperatures (370, 380, and 390 °C) were analyzed. Species of the deasphalted oils were ionized either by electrospray ionization (ESI) or by in-beam electron ionization (EI). The ESI mass spectra were obtained from every feed and processed deasphalted oil. Over 550 chemically different compounds were observed in the feed oil mass spectra. Molecular formulas for the detected peaks were calculated by using accurate mass. The compounds with one N atom as well as one N and S atoms were detected as major and minor component, respectively, in every mass spectrum. The number of the detected species in processed deasphalted oil decreases as the reaction temperature increases. However, the carbon distribution of NS-containing species shifts to high number as the reaction temperature increases. Molecular formulas distribution against Z-value (Z-value is defined as CnH2n + ZNmSsOo) and C-number were investigated for the ESI mass spectra. Z-value distribution of the peaks assigned to N-compounds was convergent in its compounds with Z = − 25 as increasing the reaction temperature. Detailed mass spectrum analysis reveals that compounds which were not detected in the feed oil were observed in the mass spectra of processed oils; N, S, and O-containing compounds. For the in-beam EI only the processed oil at 390 °C yields approximately 700 resolved peaks at adopted probe temperature (300 °C) of EI. Molecular formula analysis for the observed peaks was conducted as well as ESI. It reveals that the molecular formulas having Z-value (− 30 < Z < 2) and carbon number ranged from 8 to 31 except for (− 18 < Z < − 12, 15 < C-number < 22) were contained in the processed deasphalted oil. Using complementary ionization techniques to characterize the feed and catalytic reacted deasphalted oils provide better understanding of fuel processing conditions. 相似文献
973.
974.
975.
De la Torre T. Feltes J.W. Gomez San Roman T. Merrill H.M. 《Power Systems, IEEE Transactions on》1999,14(2):460-465
Competitive markets expose transmission planners to new uncertainties. These are handled using a decision-analysis approach whose key contribution is quantifying and minimizing risk. The method is applied using existing and generally-available software tools. The result is transmission plan which is robust in the face of uncertainties. A study of a major proposed Central-American interconnection illustrates the problem and the method 相似文献
976.
Ida Westermann Odd Sture Hopperstad Knut Marthinsen Bjrn Holmedal 《Materials Science and Engineering: A》2009,524(1-2):151
In the 7xxx aluminium alloying system several mechanisms influence the hardening behaviour of the alloys, e.g. particle size and distribution, dislocation density and alloying elements in solid solution. This work is an experimental study of ageing and work-hardening considering a commercial AA7108 alloy in the as-cast and homogenized condition. Tensile specimens have been exposed to a solution heat treatment and a two-step age-hardening treatment with varying time at the final temperature. The tensile data for the different tempers have been evaluated in elucidation of already existing models based on a one-parameter framework. The precipitate size and distribution have been further investigated in the transmission electron microscope for a selection of tempers, and the influence of these parameters on the work-hardening behaviour has been discussed. 相似文献
977.
Minor compounds in the phenolic fraction of virgin olive oils 总被引:1,自引:0,他引:1
Marcello Saitta Francesco SalvoGiuseppa Di Bella Giacomo DugoGiovanna Loredana La Torre 《Food chemistry》2009
The phenolic fraction of 34 virgin olive oils was analysed by gas chromatography–mass spectrometry (GC–MS) with the aim to identify new compounds at low level. Twenty-seven compounds previously described in olive oils were identified; several new minor compounds with phenolic structure were detected in the samples: amongst them, 4-hydroxyphenylacetaldehyde, trans-isoeugenol (trans-2-methoxy-4-(1-propenyl)-phenol), 1,4-dihydroxy-2,6-dimethoxybenzene, 3,4-dihydroxybenzyl alcohol and 3,4-dihydroxyphenylacetic acid were identified by their mass spectra and confirmed using standards. In 34 virgin olive oils (cv. Nocellara del Belice) the mean concentrations for these five substances were always below 0.2 mg kg−1 and only in two samples the level of 3,4-dihydroxyphenylacetic acid reached 1.47 and 1.97 mg kg−1, respectively. These compounds could be used to characterise olive oils; low concentrations of 3,4-dihydroxyphenylacetic acid may show the initial autoxidation processes of olive oils. 相似文献
978.
In qualitative decision-theoretic planning, desires—qualitative abstractions of utility functions—are combined with defaults—qualitative abstractions of probability distributions—to calculate the expected utilities of actions. This paper is inspired from Lang's framework of qualitative decision theory, in which utility functions are constructed from desires. Unfortunately, there is no consensus about the desirable logical properties of desires, in contrast to the case for defaults. To do justice to the wide variety of desires we define parameterized desires in an extension of Lang's framework. We introduce three parameters, which help us to implement different facets of risk. The strength parameter encodes the importance of the desire, the lifting parameter encodes how to determine the utility of a set (proposition) from the utilities of its elements (worlds), and the polarity parameter encodes the relation between gain of utility for rewards and loss of utility for violations. The parameters influence how desires interact, and they thus increase the control on the construction process of utility functions from desires. 相似文献
979.
S. Sabella V. Brunetti G. Vecchio A. Della Torre R. Rinaldi R. Cingolani P. P. Pompa 《Nanoscale research letters》2009,4(10):1222-1229
We describe the design and optimization of a reliable strategy that combines self-assembly and lithographic techniques, leading
to very precise micro-/nanopositioning of biomolecules for the realization of micro- and nanoarrays of functional DNA and
antibodies. Moreover, based on the covalent immobilization of stable and versatile SAMs of programmable chemical reactivity,
this approach constitutes a general platform for the parallel site-specific deposition of a wide range of molecules such as
organic fluorophores and water-soluble colloidal nanocrystals. 相似文献
980.
Chemical Quality of Raw Milk Retentate processed by Ultra‐filtration or Reverse Osmosis at the Dairy Farm 下载免费PDF全文
Ida Sørensen Søren Jensen Niels Ottosen Tommas Neve Lars Wiking 《International Journal of Dairy Technology》2016,69(1):31-37
Concentrating raw milk at the dairy farms – rather than at the dairy – reduces energy consumption and CO2 emission, due to less road transportation of the milk. This study demonstrates whether it is possible to use either reverse osmosis or ultra‐filtration for milk concentration at the farm without harming the milk quality, regarding lipolysis and proteolysis. Filtration at low temperature (4 °C) secures a good milk quality. Despite reverse osmosis operating at much higher feed pressures, the effect on lipolysis is small, which makes this technology the most applicable, as lactose is withhold in retentate. 相似文献