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61.
Based on the European project RES2020, the analysis evaluates the energy strategies to be implemented in Spain in order to satisfy the EU Renewable Directive. The modelling framework relies on the technico-economic model TIMES-Spain, part of the Pan-European TIMES model used in the project. TIMES is a bottom-up technology rich optimisation model representing the whole energy systems of the countries. Among the results, it appears that the gap regarding the renewable deployment in Spain between the Business-as-Usual case (including the existing policies) and the EU Directive should be compensated mainly by the penetration of bioenergy in transport and industry, and by the implementation of conservation measures, which contribute to reduce the total energy demand and thus makes useless additional investments in renewable power plants compared to the Business-as-Usual case. Only higher climate mitigation ambitions result in an absolute increase in the renewable-based electricity generation compared to the Business-as-Usual case. Moreover, when allowed, Spain is offering renewable energy credits under the statistical transfer mechanism to other European countries. The cost increase of the modelled renewable and climate policies compared to the Business-as-Usual remains relatively minor. 相似文献
62.
Yolanda Echegoyen Silvia Rodríguez 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(3):530-539
A recent trend is to use nanocomposites materials for food-packaging applications. Different kinds of nanoparticles are incorporated into the polymers to improve their characteristics, and, among them, nanoclay is used to improve their barrier properties to gases. In this work, the results of migration studies with different food simulants (ethanol 10% and acetic acid 3%), temperatures and times (40ºC for 10 days and 70ºC for 2 h) from two commercialised LDPE nanocomposite bags are presented. The migration solutions thus obtained were analysed by ICP-MS to evaluate the amount of aluminium which migrated into the solutions both in dissolved form and as a part of nanoparticles. Aluminium migration was observed for both samples with a maximum migration value of 51.65 ng cm–2 for the Aisaika bags and 24.14 ng cm–2 for the Debbie Meyer bags. The presence of spikes working in single-particle mode using ICP-MS indicated that part of this aluminium was present as nanoparticles. The size and morphology of the nanoclay, in both the original material and the migration solutions, was studied by scanning electron microscopy coupled to energy-dispersive X-ray diffraction (SEM-EDX). In this manner, nanoparticles of different morphologies and sizes were found to migrate into the food simulants. 相似文献
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Methods for fabricating poly(methyl methacrylate) microchips using a novel two-stage embossing technique and solvent welding to form microchannels in microfluidic devices are presented. The hot embossing method involves a two-stage process to create the final microchip design. In its simplest form, a mold made of aluminum is fabricated using CNC machining to create the desired microchannel design. In this work, two polymer substrates with different glass transition temperatures (Tg), polyetherimide (PEI) and poly(methyl methacrylate) (PMMA), were used to make the reusable secondary master and the final chip. First, the aluminum mold was used to emboss the PEI, a polymeric substrate with Tg approximately 216 degrees C. The embossed PEI was then used as a secondary mold for embossing PMMA, a polymeric substrate with a lower Tg ( approximately 105 degrees C). The resulting PMMA substrate possessed the same features as those of the aluminum mold. Successful feature transfer from the aluminum mold to the PMMA substrate was verified by profilometry. Bonding of the embossed layer and a blank PMMA layer to generate the microchip was achieved by solvent welding. The embossed piece was first filled with water that formed a solid sacrificial layer when frozen. The ice layer prevented channel deformation when the welding solvent (dichloroethane) was applied between the two chips during bonding. Electrophoretic separations of fluorescent dyes, rhodamine B (Rh B) and fluorescein (FL), were performed on PMMA microchips to demonstrate the feasibility of the fabrication process for microreplication of useful devices for separations. The PMMA micro-chip was tested under an electric field strength of 705 V cm-1. Separations of the test mixture of Rh B and FL generated 55 500 and 66 300 theoretical plates/meter, respectively. 相似文献
64.
Yolanda Vidal Núria Parés Pedro Díez Antonio Huerta 《International journal for numerical methods in engineering》2008,76(11):1782-1818
A novel approach to implicit residual‐type error estimation in mesh‐free methods and an adaptive refinement strategy are presented. This allows computing upper and lower bounds of the error in energy norm with the ultimate goal of obtaining bounds for outputs of interest. The proposed approach precludes the main drawbacks of standard residual‐type estimators circumventing the need of flux‐equilibration and resulting in a simple implementation that avoids integrals on edges/sides of a domain decomposition (mesh). This is especially interesting for mesh‐free methods. The adaptive strategy proposed leads to a fast convergence of the bounds to the desired precision. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
65.
Sánchez-Criado JE Trudgen K Millán Y Blanco A Monterde J Garrido-Gracia JC Gordon A Aguilar R de Las Mulas JM Ko C 《Reproduction (Cambridge, England)》2012,143(4):549-558
Estrogen receptor 1 and 2 (ESR1 and 2) mediate estrogen (E) action on gonadotrope function. While much is known about the effects of ESR1 on the gonadotrope, there is still some controversy regarding the effects of ESR2. To investigate the role of ESR2 in the gonadotrope, 45-day-old female mice of two different genotypes were used: wild type (WT) and pituitary (gonadotropes and thyrotropes)-specific Esr1 knockout (KO). All mice were ovariectomized (OVX) and 15 days later injected over 3 days with 2.5 μg 17β-estradiol (E(2)), 0.2 mg of the selective ESR1 or 2 agonists, propylpyrazole triol and diarylpropionitrile, respectively, or 0.1 ml oil. The day after treatment, anterior pituitary glands were dissected out for evaluation of gonadotrope ultrastructural morphology and pituitary immunohistochemical expression of progesterone receptor (Pgr (Pr)). Blood was collected and serum LH levels were assessed. Activation of ESR1 in WT mice resulted in the following: i) uterine ballooning and vaginal cornification, ii) negative feedback on LH secretion, iii) increased number of homogeneous (functional) gonadotropes, and iv) pituitary Pgr expression (35.9±2.0% of pituitary cells). Activation of ESR1 in KO mice induced normal uterine, vaginal, and LH secretion responses, but failed to increase the number of functional gonadotropes, and induced significantly lower Pgr expression (21.0±3.0% of pituitary cells) than in WT mice. Whilst activation of ESR2 had no significant effects in WT mice, it doubled the number of functional gonadotropes exhibited by KO mice injected with oil. It is concluded that E(2) exerted its action in KO mouse gonadotropes via ESR2. 相似文献
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Izaskun Berasategi Íñigo Navarro-Blasco Maria Isabel Calvo Rita Yolanda Cavero Iciar Astiasarán Diana Ansorena 《Meat science》2014
Reduced-energy and reduced-fat Bologna products enriched with ω-3 polyunsaturated fatty acids were formulated by replacing the pork back-fat by an oil-in-water emulsion containing a mixture of linseed-algae oil stabilized with a lyophilized Melissa officinalis extract. Healthier composition and lipid profile was obtained: 85 kcal/100 g, 3.6% fat, 0.6 g ALA and 0.44 g DHA per 100 g of product and ω-6/ω-3 ratio of 0.4. Technological and sensory problems were not detected in the new formulations. Reformulation did not cause oxidation problems during 32 days of storage under refrigeration. The results suggest that it is possible to obtain reduced-fat Bologna-type sausages rich in ALA and DHA and stabilized with natural antioxidants, applying the appropriate technology without significant effects on the sensory quality, yielding interesting products from a nutritional point of view. 相似文献
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70.
Yolanda Blanco-Fernández Martín López-Nores Alberto Gil-Solla Manuel Ramos-Cabrer José J. Pazos-Arias 《Expert systems with applications》2011,38(5):5289-5298
During the last years, we have witnessed the boom of the digital market due to the proliferation of emergent audiovisual services and the increasing number of broadband networks. In this scenario, users insistently demand innovative services for exchanging and sharing their own audiovisual contents. In order to meet these needs, in this paper we propose a system that broadcasts user-generated audiovisual contents for handheld devices in a mobile network based on the DVB-H broadcasting standard. Besides, our system offers diverse added-value services to these new active users, such as: (i) multi modal access (via Web or by client applications running locally in handheld devices) to digital contents, (ii) exploitation of return channels to transmit interactive contents that enhance the user’s experience, and (iii) annotation, sharing and personalized distribution of audiovisual contents. To achieve these goals, our system adopts well-known technologies for broadcasting and semantic annotation of audiovisual contents, as well as emergent technology from the so-called Web 2.0. A prototype of our system has been experimentally evaluated with a group of students from the University of Vigo, who were enthusiastic about the personalization capabilities offered by our TV system for a mobile setting. 相似文献