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991.
992.
993.
Inês J. Seabra Mara E. M. Braga Maria T. P. Batista Hermínio C. de Sousa 《Food and Bioprocess Technology》2010,3(5):674-683
Fractionated high pressure extractions from dry and in natura elderberry pomace were performed in order to obtain anthocyanin rich extracts. Experiments were carried out using CO2 supercritical fluid extraction followed by enhanced solvent extraction (ESE) with CO2/EtOH–H2O mixtures (1–100%, v/v), to obtain anthocyanin rich fractions in the second step, at 313 K and ~20 MPa. Higher extract yields, anthocyanin contents
and antioxidant activities occurred by the presence of water, both in the raw material and in the solvent mixture. The CO2 dissolved in the ESE solvent mixture favored either anthocyanin contents or antioxidant activities, which were not directly
related. Comparing to the literature data for elderberries and grapes, these fractions had higher anthocyanins contents. From
these results, an added economical value to this agroindustrial residue is proposed, using solvents and techniques “generally
regarded as safe” in the food and pharmaceutical industries. 相似文献
994.
995.
For many years the introduction of Electronic Health Records (EHRs) in medical practice has been considered the best way to
provide efficient document sharing among different organizational settings. The actual results of these technologies, though,
do not seem to have matched expectations. The issue of document sharing has been lately readdressed by proposing the creation
of patient-controlled information and communication technologies, Personal Health Records (PHRs), providing laypeople the
tools to access, manage and share their health information electronically by connecting to the existing EHRs and other institutional
information systems. In this scenario, patients are called to play a major role in coordinating healthcare professionals by
providing them the information they need. From a CSCW perspective the PHR offers an interesting case to reflect on cooperative
work that requires new infrastructures that intersect organizational settings and extend into domestic environments. So far
though, there has not been enough research to shed light on the self-care activities carried out in the households and how
these integrate with the organizational practices of doctors and institutions. Our analyses show that health record keeping
is an articulation work necessary for meetings with doctors to proceed smoothly. To do so, people integrate the information
contained in medical documents by working on them with annotations, underlinings and integrations. Moreover, we show that
health record keeping is a spatialized activity that is inextricably interwoven with the everyday routine and objects. Finally,
we provide a tentative classification of three different strategies laypeople use to sort out health records: minimum effort,
adaptive, networking. 相似文献
996.
Maria M Velencoso Agustin SB Gonzalez Joaquin C García‐Martínez Maria J Ramos Antonio De Lucas Juan F Rodriguez 《Polymer International》2013,62(5):783-790
A simple strategy for the synthesis and functionalization of polyurethanes is described. Anionic ring‐opening polymerization was combined with ‘click’ chemistry to synthesize polyols with fluorescent properties. This route allows the incorporation of a wide range of functionalities in the polyols with an easy, clean and highly selective process compatible with several types of functional groups. The proposed strategy opens the way to the production, in a cost‐effective way, of ‘smart’ polyurethanes with non‐conventional properties like fire retardancy, antimite properties, antibacterial properties, etc. Alkynyl groups were introduced into the polyol chains by the controlled addition of glycidyl propargyl ether as co‐monomer during a conventional anionic ring‐opening copolymerization with propylene oxide. Subsequently 4‐azidomethyl‐7‐methoxycoumarin molecules were introduced onto the alkynyl‐polyether polyols by copper‐catalysed cycloaddition reactions to produce end‐functionalized polyols. The chemical structure of the novel polyols was characterized using infrared spectroscopy, nuclear magnetic resonance spectroscopy, gel permeation chromatography with triple detection and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectroscopy. These characterization techniques confirmed the presence of a considerable amount of functional groups in the structure of the polyols. Finally, various fluorescent rigid foams, based on the functionalized polyols, were synthesized. Copyright © 2012 Society of Chemical Industry 相似文献
997.
Feng Luan Xuan Xu Huitao Liu Maria Natália Dias Soeiro Cordeiro 《Coloration Technology》2013,129(3):173-186
Dyes have been applied and are playing an increasingly important role in many industries, including the textile, printing, medical and energy industries. Their wide applications imply that specific dyes possessing given properties need to be effectively designed. The present review aims to survey information related to activity/property research of dyes that has been published in the past two decades. Emphasis is laid particularly on studies based on quantitative structure–activity/property relationships that have contributed to the theoretical design and application of dyes. Finally, the perspectives of quantitative structure‐activity/property relationship studies are set out in order to show how this method may be used to design new dyes and to evaluate their different properties. The challenges facing these studies are also outlined. 相似文献
998.
Márcia Campos Brasil Annelise Engel Gerbase Maria Augusta de Luca José Ribeiro Gregório 《Journal of the American Oil Chemists' Society》2007,84(3):289-295
Hybrid organic–inorganic films were prepared using four different hydroxylated soybean oils (HSO) or epoxidized soybean oil
as organic precursor and tetraethyl orthosilicate (TEOS) as inorganic precursor in a mass ratio of HSO:TEOS of 90:10. The
films were macroscopically homogeneous and were characterized by swelling and extraction in solvent, thermogravimetric analysis
(TGA), scanning electron microscopy (SEM) including energy dispersive spectroscopy (EDX), adhesion and hardness. Their properties
varied as a function of the number of OH groups present in the HSO. The best hybrid system was HSOF198/TEOS, with an OH value
of 198 mg of KOH/g, which presents lower swelling coefficient, very good adhesion on aluminium surface and good hardness. 相似文献
999.
In this paper we show how to establish a reliable and efficient high level communication system in a randomly deployed network of sensors equipped with directional antennas. This high level communication system enables the programming of the sensor network using high level communication functionalities without the burden of taking care of their physical capacities (low range, unidirectional links, single frequency, presence of collisions, etc.). The high level communication functionalities we offer include point-to-point communication, point-to-area communication, and one-to-all communication. The basic idea to implement this system is to simulate a virtual network that emerges from the ad-hoc network using self-organization, self-discovery and collaborative methods. We also analyse the efficiency, scalability and robustness of the proposed protocols. 相似文献
1000.
We present results of a numerical simulation of the thermal convection in the subsurface mushy ice layer of Europa, one of the Jupiter’s moons. Beside fluid dynamics and heat transfer within such a layer, heat conduction in the solid crustal surface and heat exchange between the two phases – mushy ice and solid crust – are included in our model in order to follow also the evolution of the phase front. 相似文献