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951.
S.L. Gelsinger A.J. Heinrichs C.M. Jones R.J. Van Saun D.R. Wolfgang C.M. Burns H.R. Lysczek 《Journal of dairy science》2014
Ultraviolet light is being employed for bacterial inactivation in milk for calves; however, limited evidence is available to support the claim that UV light effectively inactivates bacteria found in milk. Thus, the objective of this observational study was to investigate the efficacy of on-farm UV light treatment in reducing bacteria populations in waste milk used for feeding calves. Samples of nonsaleable milk were collected from 9 Pennsylvania herds, twice daily for 15 d, both before and after UV light treatment (n = 60 samples per farm), and analyzed for standard plate count, coliforms, noncoliform, gram-negative bacteria, environmental and contagious streptococci, coagulase-negative staphylococci, Streptococcus agalactiae, Staphylococcus aureus count, and total solids percentage, and log reduction and percentage log reduction were calculated. Data were analyzed using the mixed procedure in SAS. In all bacteria types, samples collected after UV treatment contained significantly fewer bacteria compared with samples collected before UV treatment. Weighted least squares means for log reduction (percentage log reduction) were 1.34 (29%), 1.27 (58%), 1.48 (53%), 1.85 (55%), 1.37 (72%), 1.92 (63%), 1.07 (33%), and 1.67 (82%) for standard plate count, coliforms, noncoliform, gram-negative bacteria, environmental and contagious streptococci, Strep. agalactiae, coagulase-negative staphylococci, and Staph. aureus, respectively. A percentage log reduction greater than 50% was achieved in 6 of 8 bacteria types, and 43 and 94% of samples collected after UV treatment met recommended bacterial standards for milk for feeding calves. Based on these results, UV light treatment may be effective for some, but not all bacteria types found in nonsaleable waste milk. Thus, farmers should take into account the bacteria types that may need to be reduced when considering the purchase of a UV-treatment system. 相似文献
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von Maltzahn G Park JH Lin KY Singh N Schwöppe C Mesters R Berdel WE Ruoslahti E Sailor MJ Bhatia SN 《Nature materials》2011,10(7):545-552
Nanomedicines have enormous potential to improve the precision of cancer therapy, yet our ability to efficiently home these materials to regions of disease in vivo remains very limited. Inspired by the ability of communication to improve targeting in biological systems, such as inflammatory-cell recruitment to sites of disease, we construct systems where synthetic biological and nanotechnological components communicate to amplify disease targeting in vivo. These systems are composed of 'signalling' modules (nanoparticles or engineered proteins) that target tumours and then locally activate the coagulation cascade to broadcast tumour location to clot-targeted 'receiving' nanoparticles in circulation that carry a diagnostic or therapeutic cargo, thereby amplifying their delivery. We show that communicating nanoparticle systems can be composed of multiple types of signalling and receiving modules, can transmit information through multiple molecular pathways in coagulation, can operate autonomously and can target over 40 times higher doses of chemotherapeutics to tumours than non-communicating controls. 相似文献
955.
Rauber M Alber I Müller S Neumann R Picht O Roth C Schökel A Toimil-Molares ME Ensinger W 《Nano letters》2011,11(6):2304-2310
The fabrication of three-dimensional assemblies consisting of large quantities of nanowires is of great technological importance for various applications including (electro-)catalysis, sensitive sensing, and improvement of electronic devices. Because the spatial distribution of the nanostructured material can strongly influence the properties, architectural design is required in order to use assembled nanowires to their full potential. In addition, special effort has to be dedicated to the development of efficient methods that allow precise control over structural parameters of the nanoscale building blocks as a means of tuning their characteristics. This paper reports the direct synthesis of highly ordered large-area nanowire networks by a method based on hard templates using electrodeposition within nanochannels of ion track-etched polymer membranes. Control over the complexity of the networks and the dimensions of the integrated nanostructures are achieved by a modified template fabrication. The networks possess high surface area and excellent transport properties, turning them into a promising electrocatalyst material as demonstrated by cyclic voltammetry studies on platinum nanowire networks catalyzing methanol oxidation. Our method opens up a new general route for interconnecting nanowires to stable macroscopic network structures of very high integration level that allow easy handling of nanowires while maintaining their connectivity. 相似文献
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Zhang F Lees E Amin F Rivera Gil P Yang F Mulvaney P Parak WJ 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(22):3113-3127
Water solubilization of nanoparticles is a fundamental prerequisite for many biological applications. To date, no single method has emerged as ideal, and several different approaches have been successfully utilized. These 'phase-transfer' strategies are reviewed, indicating key advantages and disadvantages, and a discussion of conjugation strategies is presented. Coating of hydrophobic nanoparticles with amphiphilic polymers provides a generic pathway for the phase transfer of semiconductor, magnetic, metallic, and upconverting nanoparticles from nonpolar to polar environments. Amphiphilic polymers that include maleimide groups can be readily functionalized with chemical groups for specific applications. In the second, experimental part, some of the new chemical features of such polymer-capped nanoparticles are demonstrated. In particular, nanoparticles to which a pH sensitive fluorophore has been attached are described, and their use for intracellular pH-sensing demonstrated. It is shown that the properties of analyte-sensitive fluorophores can be tuned by using interactions with the underlying nanoparticles. 相似文献
958.
Knoll W Caminade AM Char K Duran H Feng CL Gitsas A Kim DH Lau A Lazzara TD Majoral JP Steinhart M Yameen B Zhong XH 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(10):1384-1391
This contribution summarizes efforts in designing, assembling/synthesizing, and structurally and functionally characterizing nanostructured materials using anodized aluminum oxide (AAO) as a thin-film template. Optical waveguide spectroscopy, using a nanoporous template as the guiding structure, is a particularly powerful analytical tool. The layer-by-layer approach for the fabrication of multilayer assemblies is shown to allow the fabrication of nanotube arrays. In addition to using dendrimers as building blocks, semiconducting nanomaterial (e.g., quantum dot) hybrid architectures with very interesting photophysical properties can be assembled. These can be employed, for example, in biosensing applications. Other strategies for using the AAO layers as templates include the growth of polymeric nanorod arrays from different functional monomers, which, after the dissolution of the template, are still able to guide light. This opens up novel concepts for integrated optics platforms with nanostructured materials. 相似文献
959.
Finke Kathrin; Schwarzkopf Wolfgang; Müller Ulrich; Frodl Thomas; Müller Hermann J.; Schneider Werner X.; Engel Rolf R.; Riedel Michael; M?ller Hans-Jürgen; Hennig-Fast Kristina 《Canadian Metallurgical Quarterly》2011,120(4):890
Attention deficit hyperactivity disorder (ADHD) persists frequently into adulthood. The decomposition of endophenotypes by means of experimental neuro-cognitive assessment has the potential to improve diagnostic assessment, evaluation of treatment response, and disentanglement of genetic and environmental influences. We assessed four parameters of attentional capacity and selectivity derived from simple psychophysical tasks (verbal report of briefly presented letter displays) and based on a “theory of visual attention.” These parameters are mathematically independent, quantitative measures, and previous studies have shown that they are highly sensitive for subtle attention deficits. Potential reductions of attentional capacity, that is, of perceptual processing speed and working memory storage capacity, were assessed with a whole report paradigm. Furthermore, possible pathologies of attentional selectivity, that is, selection of task-relevant information and bias in the spatial distribution of attention, were measured with a partial report paradigm. A group of 30 unmedicated adult ADHD patients and a group of 30 demographically matched healthy controls were tested. ADHD patients showed significant reductions of working memory storage capacity of a moderate to large effect size. Perceptual processing speed, task-based, and spatial selection were unaffected. The results imply a working memory deficit as an important source of behavioral impairments. The theory of visual attention parameter working memory storage capacity might constitute a quantifiable and testable endophenotype of ADHD. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
960.
即将应用到PANDA数据获取系统与触发系统及未来BESⅢ触发系统升级的高性能计算节点[5](HPCN)符合ATCA设计规范,基于IPMI协议的智能平台管理系统为其高可靠性提供保障.自主设计的智能平台管理模块具有丰富的板级管理功能,如Hot Swap和电源分配协调,板上器件状态监控,与机箱控制器的协调通信等.主要介绍了智... 相似文献