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91.
The U.S. Coast Guard's Office of Research and Development is presently conducting a program to develop equipment and methods for responding to discharges of hazardous chemicals into the waters of the United States. The program to ameliorate hazardous chemical discharges has been divided into six project areas. This paper will provide an overview of these six project areas as follows:1. Prevention and Reduction: The development of techniques to prevent or reduce the discharge of a hazardous chemical.2. Personnel Protection: The development of protective clothing, life support systems and personnel monitors for personnel responding to chemical discharges.3. Detection, Identification, and Quantification: The development of techniques to allow response personnel to detect, identify and determine the concentration of hazardous chemical discharges.4. Hazard Assessment Modeling: The development and refinement of mathematical models to predict the behavior of discharged hazardous chemicals.5. Containment, Treatment, and Recovery: The development of hardware and methods to respond to a discharge and mitigate its environmental damage.6. Disposal: The development of methods to dispose of chemicals which have been recovered.When completed, each of these project areas should provide the Coast Guard with additional capability to respond to hazardous chemical discharges. 相似文献
92.
Yakush S. Andrew Willey T. Joe Park Ted C. Maeda George 《IEEE transactions on bio-medical engineering》1982,(1):55-56
A multicomputer array is described that speeds up the processing of spectral representation for the EEG. 相似文献
93.
Frank H. Chang George E. Santee Jr. Glen A. Mortensen Michael B. Gross Ted B. Belytschko 《Nuclear Engineering and Design》1982,70(3):335-355
A methodology for realistically analyzing three-dimensional fluid-structure interaction effects and the resulting hydrodynamic loads during the subcooled portion of a hypothetical loss of coolant accident (LOCA) in a pressurized water reactor (PWR) is discussed. The methodology uses a hydrodynamic computer program, STEALTH 3D, coupled with a structural response program, WHAMSE 3D, to calculate the dynamic interaction of fluid and structure during a reactor vessel blowdown. This coupled program is user oriented and highly versatile in modeling the various components in complex reactor systems. Assessment of the methodology is provided by STEALTH/WHAMSE 3D calculations of blowdown tests in the German Battelle-Frankfurt RS-16B facility (Test DWR5) and the HDR facility (Test V31.1). The calculations are described and the results compared with experimental data. Agreement between the calculational results and experimental data is extremely good. 相似文献
94.
Brown Rachel; Pressley Michael; Van Meter Peggy; Schuder Ted 《Canadian Metallurgical Quarterly》1996,88(1):18
Second-grade, low-achieving students experienced a year of either transactional strategies instruction or highly regarded, more conventional second-grade reading instruction. By the end of the academic year, there was clear evidence of greater strategy awareness and strategy use, greater acquisition of information from material read in reading group, and superior performance on standardized reading tests by the transactional strategies instruction students. This is the clearest validation to date of educator-developed transactional strategies instruction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Devanand Luthria Ajay P. Singh Ted Wilson Nicholi Vorsa Gary S. Banuelos Bryan T. Vinyard 《Food chemistry》2010
Consumer awareness, pesticide and fertiliser contaminations, and environmental concerns have resulted in significant demand for organically grown farm products. The present study evaluates the influence that organic and conventional farming practices exert on the total phenolic content in eggplant samples from two cultivars, Blackbell (American eggplant) and Millionaire (Japanese eggplant), grown by conventional and organic farming practices with similar climatic conditions. In addition, plant-to-plant variation in phenolic content was determined from eight eggplant samples collected from different plants grown at various field positions. Samples were separately assayed for phenolic content by the two independent procedures, HPLC/LC–MS and Folin–Ciocalteu assay. The results of the HPLC analysis showed significant plant-to-plant variation (% RSD ranged from 22% to 48%) in 5-caffeoylqunic acid content (the most abundant phenolic acid) in eight eggplant samples collected from eight different plants belonging to the same cultivar and grown under similar conditions. The cv. Millionaire showed a higher total phenolic content compared to the Blackbell cultivar. We did not observe significant consistent trend in the phenolic content of eggplant samples grown with organic and conventional farming practices with both eggplant cultivars. We, however, observed a strong correlation (R2 = 0.87) between total phenolic content as assayed by Folin–Ciocalteu assay and 5-caffeoylqunic acid, a major phenolic acid in eggplant extract. This study concludes that multiple repetitive analyses of plant products collected from different plants grown over various time periods (seasons) at different locations should always be carried to unambiguously prove the impact of growing conditions on phenolic content or antioxidant activity. 相似文献
96.
Fungal Infection Reduces Herbivore-Induced Plant Volatiles of Maize but does not Affect Naïve Parasitoids 总被引:3,自引:2,他引:1
Plants attacked by insects release volatile compounds that attract the herbivores' natural enemies. This so-called indirect defense is plastic and may be affected by an array of biotic and abiotic factors. We investigated the effect of fungal infection as a biotic stress agent on the emission of herbivore-induced volatiles and the possible consequences for the attraction of two parasitoid species. Maize seedlings that were simultaneously attacked by the fungus Setosphaeria turcica and larvae of Spodoptera littoralis emitted a blend of volatiles that was qualitatively similar to the blend emitted by maize that was damaged by only the herbivore, but there was a clear quantitative difference. When simultaneously challenged by fungus and herbivore, the maize plants emitted in total 47% less of the volatiles. Emissions of green leaf volatiles were unaffected. In a six-arm olfactometer, the parasitoids Cotesia marginiventris and Microplitis rufiventris responded equally well to odors of herbivore-damaged and fungus- and herbivore-damaged maize plants. Healthy and fungus-infected plants were not attractive. An additional experiment showed that the performance of S. littoralis caterpillars was not affected by the presence of the pathogen, nor was there an effect on larvae of M. rufiventris developing inside the caterpillars. Our results confirm previous indications that naïve wasps may respond primarily to the green leaf volatiles. 相似文献
97.
Jiqing Lu Xiaoming Zhang Juan J. Bravo-Surez Tadahiro Fujitani S. Ted Oyama 《Catalysis Today》2009,147(3-4):186
A series of Au/titanium silicalite-1 (TS-1) catalysts with different Si/Ti ratios and promoted with alkali and alkaline earth cations were prepared by deposition–precipitation (DP) and tested for direct propylene epoxidation. It was found that the gold loading and catalytic activity was highly dependent on the pH of the DP synthesis solution and the final composition of the catalyst. Addition of Group 1 metals such as K or Cs had little effect on the gold content, but increased activity, while Group 2 metals such as Mg, Ca, Sr, and Ba increased both the gold content and the catalytic activity. The highest improvement was provided by a Mg promoted catalyst, which at 443 K and 0.1 MPa with a H2/O2/C3H6/Ar = 1/1/1/7 feed mixture gave a propylene oxide (PO) formation rate of 88 gPO h−1 kgcat−1, compared to 57 gPO h−1 kgcat−1 for an unpromoted catalyst, corresponding to a 50% enhancement of activity. Ammonia temperature-programmed desorption (NH3-TPD) measurements indicated little change in adsorption amount with promotion indicating that the yield increase was not due to the elimination of acidic sites on the catalyst. Instead, the improved catalytic performance was ascribed to increased Au capture efficiency and dispersion by the catalyst. The effect of Si/Ti ratio, pH of synthesis, and the promoter ions on the gold content could be understood from their effect on the surface charge of the support. 相似文献
98.
Strong atmospheric winds may cause wind erosion and dust emissions on bare, dry, erodible fields. Since these dust emissions may exceed particulate matter limits established by the United States Environmental Protection Agency, information on dust generation and transport mechanics is needed to determine the particulate hazard of dust sources. Measurements of climatic variables and airborne sediment mass and concentration were made during three strong wind events on a bare, fine sandy loam field in west Texas. This study clearly shows that dust flux estimates were very sensitive to dust concentration measurement height. PM10 flux values estimated between heights of 2 and 5m were 2-5 times those estimated between heights of 5 and 10 m. Tower placement in relation to the upwind unerodible boundary produced significant differences in dust flux that varied with storm intensity. During the most intense storm event, the PM10 flux between heights of 2 and 5m measured at the tower 200 m from the unerodible boundary was almost 2.5 times as that measured at the tower 100 m from the unerodible boundary. Vertical PM10 dust flux was closely related with horizontal sediment flux only when the winds came from the same direction during the entire duration of horizontal sediment flux measurements. 相似文献
99.
Ted Salazar 《电子产品世界》2004,(1):68-69,82
概述 为提高数据的传输速率、方便用户操作,现代电子设备常常采用新型接口电路实现数据通信,IrDA利用无线方式进行数据通信,操作简单,是目前接口设计的优选方案之一.实际应用中,有些设备并不支持新型接口电路,需要设计方案向下兼容、支持传统的RS-232接口,这时仅采用一种接口方案无法满足系统要求,正是考虑到这一需求,现代产品往往同时支持IrDA和RS-232两种接口标准. 相似文献
100.
Bruno Barazani Marta Piercey Allan Paulson Stephan Warnat Ted Hubbard Andrew J. MacIntosh 《Journal of the Institute of Brewing》2019,125(1):53-59
This study investigated the rehydration of active dried yeast and the impact of temperature and wort density on the strength and stiffness of individual cells using a microelectromechanical system. Dried yeast was rehydrated using a variety of methods, including direct pitching into wort (13.6°P) at 12, 22 and 30°C, as well as propagation using YEPD media (4.2°P). Cell viability was found to broadly correlate with measurement of cell strength and stiffness. Both wort density and temperature affected viability and physical characteristics of the cells after 1 h of rehydration. Yeast cells rehydrated at low temperature and high wort density burst at a lower force (0.26 ± 0.02 μN) than cells rehydrated using high temperature and low density media (0.50 ± 0.10 μN). Cells rehydrated at higher temperatures or using low density media showed no significant difference in strength and stiffness when compared with high viability, actively fermenting yeast. Changes in yeast physiology, owing to stress responses, may contribute to the observed differences in mechanical properties. These findings have application in brewery design, as pumping, centrifugation, storage and associated shear impart mechanical stress upon yeast cells. © 2018 The Institute of Brewing & Distilling 相似文献