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61.
Changes in Retinal N-Acylethanolamines and their Oxylipin Derivatives During the Development of Visual Impairment in a Mouse Model for Glaucoma 下载免费PDF全文
Christa L. Montgomery Jantana Keereetaweep Heather M. Johnson Stephanie L. Grillo Kent D. Chapman Peter Koulen 《Lipids》2016,51(7):857-866
Neurons are especially susceptible to oxidative damage, which is increasingly implicated in neurodegenerative disease. Certain N‐acylethanolamines (NAEs) have been shown to protect neurons from oxidative stress. Since glaucoma may be considered a neurodegenerative disorder and the survival of retinal neurons could also be influenced by N‐acylethanolamines, our goal was to quantify changes in certain N‐acylethanolamine species and their oxylipin derivatives in the retina of a mouse model for glaucoma. We also sought to identify relationships between these and parameters of glaucoma disease development, specifically intraocular pressure, visual acuity, and contrast sensitivity. Five N‐acylethanolamine species and three NAE oxylipin derivatives were quantified in retina from young and aged DBA/2Crl mice. N‐Acylethanolamines and NAE‐oxylipins in retinal extracts were quantified against deuterated standards by isotope dilution gas chromatography–mass spectrometry. Levels (nmol/g dry weight) of N‐arachidonoylethanolamine (anandamide; NAE 20:4) were significantly (p = 0.008) decreased in aged (2.875 ± 0.6702) compared to young animals (5.175 ± 0.971). Conversely, the anandamide oxylipin, 15(S)‐HETE ethanolamide (15(S)‐HETE EA), was significantly (p = 0.042) increased in aged (0.063 ± 0.009) compared to young animals (0.039 ± 0.011). Enzymatic depletion of the anandamide pool by 15‐lipoxygenase and consequent accumulation of 15(S)‐HETE ethanolamine may contribute to decreased visual function in glaucomatous mice. Since N‐acylethanolamines effectively attenuate glaucoma pathogenesis and associated visual impairment, our data provides additional rationale and novel targets for glaucoma therapies. 相似文献
62.
Cokley Kevin O.; Tran Kimberly; Hall-Clark Brittany; Chapman Collette; Bessa Luana; Finley Angela; Martinez Michael 《Canadian Metallurgical Quarterly》2010,3(3):187
[Correction Notice: An erratum for this article was reported in Vol 4(3) of Journal of Diversity in Higher Education (see record 2011-16523-001). There are two errors in Table 2 under the RWA heading and the Cog-gender heading. The necessary changes are provided in the erratum.] [Correction Notice: An erratum for this article was reported in Journal of Diversity in Higher Education on August 1 2011 (see record 2011-16523-001). There are two errors in Table 2. Under the RWA heading, the SDO row should have indicated a positive correlation of .266**, not -.266**. Under the Cog-gender heading, the SDO row should have indicated a negative correlation of -.438**, not .438**.] Factors related to attitudes about racial diversity and gender equity were examined in an ethnically diverse sample of 432 college students (167 European Americans, 83 African Americans, 81 Asian Americans, and 82 Hispanic Americans). In addition to variables of self-interest (i.e., ethnicity, gender, and political views), social ideology (i.e., social dominance orientation, right-wing authoritarianism) and personality traits (openness to experience) were uniquely predictive of attitudes about racial diversity and gender equity. Hierarchical regressions revealed that social dominance orientation most strongly predicted racial attitudes, while right-wing authoritarianism most strongly predicted gender attitudes. Implications for diversity education efforts related to prejudice reduction are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
63.
Haoqiang Jin Barbara Chapman Lei Huang Dieter an Mey Thomas Reichstein 《International journal of parallel programming》2008,36(3):312-325
We describe a performance study of a multi-zone application benchmark implemented in several OpenMP approaches that exploit
multi-level parallelism and deal with unbalanced workload. The multi-zone application was derived from the well-known NAS
Parallel Benchmarks (NPB) suite that involves flow solvers on collections of loosely coupled discretization meshes. Parallel
versions of this application have been developed using the Subteam concept and Workqueuing model as extensions to the current
OpenMP. We examine the performance impact of these extensions to OpenMP and compare with hybrid and nested OpenMP approaches
on several large parallel systems. 相似文献
64.
65.
A. Rosenqvist M. Shimada B. Chapman A. Freeman G. De Grandi S. Saatchi 《International journal of remote sensing》2013,34(6-7):1375-1387
The Global Rain Forest Mapping (GRFM) project is an international endeavour led by the National Space Development Agency of Japan (NASDA), with the aim of producing spatially and temporally contiguous Synthetic Aperture Radar (SAR) data sets over the tropical belt on the Earth by use of the JERS-1 L-band SAR, through the generation of semi-continental, 100 m resolution, image mosaics. The GRFM project relies on extensive collaboration with the National Aeronautics and Space Administration (NASA), the Joint Research Centre of the European Commission (JRC) and the Japanese Ministry of International Trade and Industry (MITI) for data acquisition, processing, validation and product generation. A science programme is underway in parallel with product generation. This involves the agencies mentioned above, as well as a large number of international organizations, universities and individuals to perform field activities and data analysis at different levels. The GRFM project was initiated in 1995 and, through a dedicated data acquisition policy by NASDA, data acquisitions could be completed within a 1.5-year period, resulting in a spatially and temporally homogeneous coverage to encompass the entire Amazon Basin from the Atlantic to the Pacific; Central America up to the Yucatan Peninsular in Mexico; equatorial Africa from Madagascar and Kenya in the east to Sierra Leone in the west; and south-east Asia, including Papua New Guinea and northern Australia. Over the Amazon and Congo river basins, the project aimed to provide complete cover at two different seasons, featuring the basins at high and low water. In total, the GRFM acquisitions comprise some 13000 SAR scenes, which are currently in the course of being processed and compiled into image mosaics. In March 1999, SAR mosaics over the Amazon Basin (one out of two seasonal coverages) and equatorial Africa (both seasonal coverages) were completed; the data are available on CD-ROM and, at a coarser resolution, via the Internet. Coverage of the second-season Amazon and Central America will be completed during 1999, with the south-east Asian data sets following thereafter. All data are being provided free of charge to the international science community for research and educational purposes. 相似文献
66.
Hazard perception is one of the most important facets of driving and if the appropriate diagnostic tool is used it can discriminate between novice and experienced drivers. In this study video clips of actual driving scenarios were shown to novice and experienced drivers. The clips were stopped just prior to hazard onset and either the screen went black or the final still image stayed on the screen. Participants were then asked five questions about what happened next. This variant of the hazard perception test allowed the influence of processing time to be included and the level of situation awareness to be measured. Experienced drivers significantly anticipated more correct hazardous outcomes than novice drivers when the screen went black. Novice drivers benefited from the extra processing time afforded by the image remaining on the screen and significantly anticipated more hazards when the image remained on the screen than when it went black. The findings indicate that when processing time is manipulated, hazard perception accuracy reveals experiential differences. These differences are discussed with reference to hazard perception and situation awareness. This research informs the current controversy over whether hazard perception is a good diagnostic tool for driving performance. It identifies potential confounds in previous work and demonstrates that experiential differences can be found if the appropriate tests are used. Further, it suggests improvements for new hazard perception tests. 相似文献
67.
Real-time underwater visualization has been extremely slow to develop within the offshore industry and has generally been limited to 2D representations of vessel positions on digital charts. Only recently have marine industries realized the potential of 3D real-time virtual environments and visualization systems for effective management planning and real-time situation awareness. We describe a real-time visualization of the clean-up of a former US Naval Submarine Base, located in Holy Loch, Scotland. Our Whole-Field Modeling System has provided an accurate real-time visualization of numerous varying parameters such as remotely operated vehicles (ROVs), cranes, barges, grabs, magnets, and detailed seabed topography. The system improved the field staffs' spatial and temporal awareness and facilitated decision making within the complex offshore working environment. A side bar discusses another application, offshore diamond mining 相似文献
68.
Andrew Ireland Bill J. Ellis Andrew Cook Roderick Chapman Janet Barnes 《Journal of Automated Reasoning》2006,36(4):379-410
Using automated reasoning techniques, we tackle the niche activity of proving that a program is free from run-time exceptions.
Such a property is particularly valuable in high integrity software, for example, safety- or security-critical applications.
The context for our work is the SPARK Approach for the development of high integrity software. The SPARK Approach provides
a significant degree of automation in proving exception freedom. Where this automation fails, however, the programmer is burdened
with the task of interactively constructing a proof and possibly also having to supply auxiliary program annotations. We minimize
this burden by increasing the automation, through an integration of proof planning and a program analysis oracle. We advocate
a ‘cooperative’ integration, where proof-failure analysis directly constrains the search for auxiliary program annotations.
The approach has been successfully tested on industrial data. 相似文献
69.
70.
The use of lidar (light detection and ranging), an active light-emitting instrument, is becoming increasingly common for a range of potential applications. Its ability to provide fine-resolution spatial and vertical-resolution elevation data makes it ideal for a wide range of studies. This article demonstrates the ability of lidar data to measure sky-view factors (ψs). The lidar data are used to generate a spatial map of ψs, which are then compared against photographically derived ψs at selected locations. At each location, three near-surface elevation measurements were taken and compared with collocated lidar-derived estimates. Generally a good agreement was found between the two methodologies, although with decreasing ψs, the lidar technique tended to overestimate ψs. This can be attributed in part to the spatial resolution of the lidar sampling. Nevertheless, airborne lidar systems can easily map ψs over a large area, potentially improving the use of such data in atmospheric and meteorological models. 相似文献