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11.
分辨率增强技术(RET)设计流程中聚集了各式各样的点工具和方法。当前对深亚波长可制造性(DFM)设计的要求迫使设计与制造行业必须建立十分密切的合作关系。同时也促使EDA行业提供一种平台,以促进这些行业间的密切交流。合理利用这一平台将会对产能和品质产生直接的影响。 相似文献
12.
Three-dimensional distinct element modelling and dynamic runout analysis of a landslide in gneissic rock, British Columbia, Canada 总被引:1,自引:1,他引:0
Marc-André Brideau Scott McDougall Doug Stead Steve G. Evans Réjean Couture Kevin Turner 《Bulletin of Engineering Geology and the Environment》2012,71(3):467-486
The McAuley Creek Landslide is a 6?million m3 gneissic rock slope failure that occurred in British Columbia (Canada) in late May–early June 2002. The geological strength index was used to characterize the quality of the overall rock mass and its reduced (damaged) quality near tectonic structures and alteration zones. Potential slope failure mechanisms were investigated using four analysis techniques including: kinematic analysis, surface wedge limit equilibrium (combination) analysis, block theory and three-dimensional distinct element models. Results from all four analyses suggested that the dominant slope failure mechanism was wedge sliding along the intersection of the gneissic foliation and a steeply dipping discontinuity set striking perpendicular to the slope. Of the 6?million m3 of material involved in the landslide, an estimated 5 million?m3 was deposited immediately below the source area against the opposite valley wall, with the remaining 1 million m3 travelling an additional 1.6?km downstream. The runout behaviour was investigated using a three-dimensional dynamic analysis code. 相似文献
13.
14.
Reduced Maternal Erythrocyte Long Chain Polyunsaturated Fatty Acids Exist in Early Pregnancy in Preeclampsia 下载免费PDF全文
Nisha S. Wadhwani Ankita S. Narang Savita S. Mehendale Girija N. Wagh Sanjay A. Gupte Sadhana R. Joshi 《Lipids》2016,51(1):85-94
The present prospective study examines proportions of maternal erythrocyte fatty acids across gestation and their association with cord erythrocyte fatty acids in normotensive control (NC) and preeclamptic pregnancies. We hypothesize that maternal fatty acid status in early pregnancy influences fetal fatty acid stores in preeclampsia. 137 NC women and 58 women with preeclampsia were included in this study. Maternal blood was collected at 3 time points during pregnancy (16–20th weeks, 26–30th weeks and at delivery). Cord blood was collected at delivery. Fatty acids were analyzed using gas chromatography. The proportions of maternal erythrocyte α‐linolenic acid, docosahexaenoic acid, nervonic acid, and monounsaturated fatty acids (MUFA) (p < 0.05 for all) were lower while total n‐6 fatty acids were higher (p < 0.05) at 16–20th weeks of gestation in preeclampsia as compared with NC. Cord 18:3n‐3, 22:6n‐3, 24:1n‐9, MUFA, and total n‐3 fatty acids (p < 0.05 for all) were also lower in preeclampsia as compared with NC. A positive association was observed between maternal erythrocyte 22:6n‐3 and 24:1n‐9 at 16–20th weeks with the same fatty acids in cord erythrocytes (p < 0.05 for both) in preeclampsia. Our study for the first time indicates alteration in maternal erythrocyte fatty acids at 16th weeks of gestation which is further reflected in cord erythrocytes at delivery in preeclampsia. 相似文献
15.
David W. Niles Xiaonan Li David Albin Doug Rose Timothy Gessert Peter Sheldon 《Progress in Photovoltaics: Research and Applications》1996,4(3):225-229
A commonly used process for forming low-resistance contacts to thin-film p-type CdTe involves the formation of a Te layer by etching the CdTe film in a concentrated mixture of nitric and phosphoric acids. The authors compare evaporated Te back contacts with ‘control’ back contacts formed by the usual etching process, and demonstrate that evaporating Te onto a CdTe thin film is a viable process for forming a low-resistance contact. The best efficiency achieved for a CdTe solar cell made with an evaporated Te back contact is 12.1%, whereas the efficiency of the device made with the control back contact was 11.9%. The evaporation process offers numerous advantages over acid etching, most notably vacuum compatibility amenable to large-scale production of CdTe solar cell modules. 相似文献
16.
An in vitro assay was developed to measure the ability of competitive exclusion (CE) bacteria to protect Caco-2 and CRL-2117 epithelial cells from invasion by Salmonella Typhimurium. The proposed assay is needed to expedite the development of defined-flora CE products. The average significantly protective concentration of the commercial poultry-specific CE product Preempt was 4.05 log CFU/6.41 log human Caco-2 cells and 3.71 log CFU/6.89 log CFU chicken CRL-2117 cells, Enterococcus faecalis isolated from Preempt protected CRL-2117 cells, Escherichia coli isolates protected Caco-2 cells, Lactococcus lactis and Bacteroides distasonis isolates protected both cell lines, and three species of Lactobacillus isolates failed to protect either cell line. A defined mixture of 29 strains of bacteria similar to the constituents of Preempt protected both cell lines from Salmonella invasion at a concentration of 7.83 log CFU. The constituents of the defined CE culture were separated into mixtures of obligate (8.42 log CFU) and facultative (8.49 log CFU) anaerobes, which both protected the cell lines, suggesting that both types of bacteria were equally protective. Although not a substitute for in vivo testing, the in vitro CE assay is a rapid technique for the evaluation of bacterial mixtures for potential CE products. 相似文献
17.
An intensive survey of water quality parameters was conducted on Lake Michigan during 1976 and 1977. A dynamic phytoplankton simulation model (MICH1) was developed to investigate the observed field data and to use in forecasting lake responses to various phosphorus loading scenarios. The 1977 data indicated that the southern basin of Lake Michigan lost up to 3 μg P/ L compared to concentrations observed in 1976. In an attempt to simulate this rapid depletion of phosphorus, MICH1 required an implicit representation of suspected effects of an extensive ice cover observed during the winter of 1976–77. This included increasing the net apparent settling rate eight fold during ice cover. A total phosphorus model (TPM) was used in conjunction with MICH1 ;for forecasting. These forecasts indicate a steady-state total phosphorus concentration of 7 μg P/ L, given a target load recommended by the 1978 Water Quality Agreement. The projected time to obtain 95% of steady-state response to a load change was 7–14 years. 相似文献
18.
Information-rich virtual environments (IRVEs) have been described as environments in which perceptual information is enhanced with abstract (or symbolic) information, such as text, numbers, images, audio, video, or hyperlinked resources. Desktop virtual environment (VE) applications present similar information design and layout challenges as immersive VEs, but, in addition, they may also be integrated with external windows or frames commonly used in desktop interfaces. This paper enumerates design approaches for the display of enhancing information both internal and external to the virtual worlds render volume. Using standard Web-based software frameworks, we explore a number of implicit and explicit spatial layout methods for the display and linking of abstract information, especially text. Within the VE view, we demonstrate both heads-up-displays
(HUDs) and encapsulated scenegraph behaviors we call
semantic objects. For desktop displays, which support information display venues external to the scene, we demonstrate the linking and integration of the scene with Web browsers and external visualization applications. Finally, we describe the application of these techniques in the PathSim visualizer, an IRVE interface for the biomedical domain. These design techniques are relevant to instructional and informative interfaces for a wide variety of VE applications. 相似文献
19.
Pseudovoltammetry was used to evaluate the actual Pb complexation occurring in natural water samples of varying oxygen and sulfide concentration. In pseudovoltammetry, the potential at which metal-ligand complexes are broken up to form the metal amalgam is used to determine the complexes' thermodynamic stability constants (KTHERM; corrected for metal and ligand side reaction coefficients) via the Nernst expression. This methodology removes the need for any metal additions and for subsequent modeling using fitting criteria, which provide only conditional stability constant data (KCOND). Using known organic ligands, a chelate scale ranging from log KTHERM = 4 to log KTHERM = 20 was developed as a template for comparison with samples collected from two stations of different salinities and at several depths in the Chesapeake Bay. These samples were observed to contain up to five different ligand compounds of unknown structural composition (log KTHERM > 8) with the strongest ligand fraction exceeding log KTHERM > 39 (the maximum observable thermodynamic stability constant due to the reduction of Na+). One possible explanation for the observed complexation is the existence of lead sulfide clusters. This was supported by laboratory experiments using electrochemistry and ICR-FTMS, which confirmed the formation of electrochemically inert multinuclear clusters with high stability constants (e.g., M3S3, log KTHERM = 62.9). However, in all field samples, (sub)nanomolar levels of acid-leachable sulfide were recovered at pH 5.0-6.2, which could be attributed to dissociation of lead sulfide complexes with moderate acidity. Recovery of sulfide increased from < 10% of the total dissolved Pb concentration (Pbdiss) in surface waters to 100% of the Pbdiss in the sulfide-rich bottom waters at the higher salinity location. 相似文献
20.
Jason SJ Pulinets S da Silva Curiel A Liddle D 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2003,361(1802):169-173
Reliable, repeatable earthquake forecast is a subject surrounded by controversy and scepticism. What is clear is that reliable forecast would be a critical tool for effective earthquake disaster management. It is proposed that satellites and ground-based facilities may detect earthquake precursors in the ionosphere a few hours or days before the main shock. A low-cost 100 kg class satellite carrying a topside sounder is proposed, to make systematic measurements over seismically active zones. The mission aims to confirm or refute the hypothesis of ionospheric earthquake precursors, define the reliability and reproducibility, and enable further scientific understanding of their mechanisms. 相似文献