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V.A. Popovich M. JanssenI.M. Richardson T. van AmstelI.J. Bennett 《Solar Energy Materials & Solar Cells》2011,95(1):93-96
The overall demand to reduce solar energy costs gives a continuous drive to reduce the thickness of silicon wafers. Handling and bowing problems associated with thinner wafers become more and more important, as these can lead to cells cracking and thus to high yield losses. In this paper the microstructure and mechanical properties of the aluminum on the rear side of a solar cell are discussed. It is shown that the aluminum back contact has a complex composite-like microstructure, consisting of five main components: (1) the back surface field layer; (2) a eutectic layer; (3) spherical (3-5 μm) hypereutectic Al-Si particles surrounded by a thin aluminum oxide layer (200 nm); (4) a bismuth-silicate glass matrix; and (5) pores (14 vol%). The Young’s modulus of the Al-Si particles is estimated by nanoindentation and the overall Young’s modulus is estimated on the basis of bowing measurements. These results are used as input parameters for the improved thermomechanical multiscale model of a solar cell. 相似文献
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Metal–Organic Frameworks: Biomimetic Replication of Microscopic Metal–Organic Framework Patterns Using Printed Protein Patterns (Adv. Mater. 45/2015) 下载免费PDF全文
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Progress towards a methodology for high throughput 3D reconstruction of soot nanoparticles via electron tomography 下载免费PDF全文
The aim of this work is to make progress towards the development of 3D reconstruction as a legitimate alternative to traditional 2D characterization of soot. Time constraints are the greatest opposition to its implementation, as currently reconstruction of a single soot particle takes around 5–6 h to complete. As such, the accuracy and detail gains are currently insufficient to challenge 2D characterization of a representative sample (e.g. 200 particles). This work is a consideration of the optimization of the steps included within the computational reconstruction and manual segmentation of soot particles. Our optimal process reduced the time required by over 70% in comparison to a typical procedure, whilst producing models with no appreciable decrease in quality. 相似文献
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A collaborative industry-government research program was carried out at the National Research Council Canada (NRC) to develop new sound-transmission-class and fire-resistance ratings for gypsum-board protected walls. Forintek Canada Corp. and the Canadian Wood Council participated in the program on behalf of Canada's wood industry. As a result of that NRC research program, sound-transmission-class (STC) and fire-resistance (FR) ratings were formulated for approximately 140 gypsum-protected wood-frame walls. Fire-resistance ratings for the walls range from 30 minutes to 2 hours. Sound-transmission-class ratings range from 30 to 65. Sound-transmission-class and fire-resistance ratings for approximately 90 of the wall designs appear in the 1995 edition of the National Building Code of Canada (NBCC). This paper highlights some of those STC and FR ratings and describes how they were derived from the data obtained through the research program. 相似文献
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P She A R Hippen J W Young G L Lindberg D C Beitz L F Richardson R W Tucker 《Journal of dairy science》1999,82(6):1118-1127
Twenty cows were assigned at parturition to two groups to study metabolic effects of continuous intravenous infusions of glucagon. Groups were control cows and cows treated with glucagon at 10 mg/d for 14 d starting at d 21 postpartum. Daily blood samples and nine liver biopsies were taken from d 7 to 49 postpartum. Plasma glucagon increased six- to seven-fold during infusions of treated cows. Plasma insulin was increased heterogeneously by glucagon infusions. Plasma glucose increased 11.5 and 9.0 mg/dl during wk 1 and 2 of glucagon infusions. No other plasma metabolites tested (nonesterified fatty acids, beta-hydroxybutyrate, and urea N) were affected by glucagon infusions. Liver glycogen decreased by d 2 of glucagon infusion but was repleted to preinfusion values by d 7 and increased to 169% of the preinfusion baseline values at 3 d after cessation of glucagon. Milk production decreased transiently during glucagon infusions. Both milk production and milk protein percentage decreased during glucagon infusion, which could imply a decreased availability of amino acids for milk protein synthesis. Feed intakes did not increase during glucagon infusions, which was in contrast to the control group. Results indicated that glucagon infusions caused liver glycogenolysis initially and probably enhanced gluconeogenesis but glucagon did not appear to increase lipolysis from adipose tissue in these early lactating dairy cows. 相似文献
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Plewa MJ Muellner MG Richardson SD Fasano F Buettner KM Woo YT McKague AB Wagner ED 《Environmental science & technology》2008,42(3):955-961
The haloacetamides, a class of emerging nitrogenous drinking water disinfection byproduct (DBPs), were analyzed for their chronic cytotoxicity and for the induction of genomic DNA damage in Chinese hamster ovary cells. The rank order for cytotoxicity of 13 haloacetamides was DIAcAm > IAcAm > BAcAm > TBAcAm > BIAcAm > DBCAcAm > CIAcAm > BDCAcAm > DBAcAm > BCAcAm > CAcAm > DCAcAm > TCAcAm. The rank order of their genotoxicity was TBAcAm > DIAcAm approximately equal to IAcAm > BAcAm > DBCAcAm > BIAcAm > BDCAcAm > CIAcAm > BCAcAm > DBAcAm > CAcAm > TCAcAm. DCAcAm was not genotoxic. Cytotoxicity and genotoxicity were primarily determined by the leaving tendency of the halogens and followed the order I > Br > > Cl. With the exception of brominated trihaloacetamides, most of the toxicity rank order was consistent with structure-activity relationship expectations. For di- and trihaloacetamides, the presence of at least one good leaving halogen group (I or Br but not Cl) appears to be critical for significant toxic activity. Log P was not a factor for monohaloacetamides but may play a role in the genotoxicity of trihaloacetamides and possible activation of dihaloacetamides by intracellular GSH and -SH compounds. 相似文献