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531.
Adam Jos J.; Nieuwenstein Jimmy H.; Huys Raoul; Paas Fred G. W. C.; Kingma Herman; Willems Paul; Werry Marieke 《Canadian Metallurgical Quarterly》2000,26(1):295
A series of 8 experiments examined the phenomenon that a rapid aimed hand movement is executed faster when it is performed as a single, isolated movement than when it is followed by a second movement (the 1-target advantage). Three new accounts of this effect are proposed and tested: the eye movement hypothesis, the target uncertainty hypothesis, and the movement integration hypothesis. Data are reported that corroborate the 3rd hypothesis, but not the first 2 hypotheses. According to the movement integration hypothesis, the first movement in a series is slowed because control of the second movement may overlap with execution of the first. It is shown that manipulations of target size and movement direction mediate this process and determine the presence and absence of the 1-target advantage. Possible neurophysiological mechanisms and implications for motor control theory are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
532.
533.
A mild solvothermal route for preparation of cubic-like CuInS2 crystals was developed by using benzyl alcohol as the reaction medium and In(NO3)3·9H2O, CuCl2·2H2O and thiourea as the precursors. The as-synthesized CuInS2 crystals were characterized by XRD, XPS, SEM, and TEM. The characterizations showed that the synthesized CuInS2 crystals had stoichiometric composition and good crystallinity. Moreover, the prepared CuInS2 crystals show good cubic-like morphology with the size from 100 to 200 nm. 相似文献
534.
Jimmy Bruner Larry Birkemo Kelly Jordan Glenn Smith James Ormand 《Journal of The Association for Laboratory Automation》2001,6(5):64
Liquid-handling platforms often do not provide a mechanism for collecting weight data needed for instrument qualification and sample transfer confirmation. This paper discusses the development, implementation, and application of a system that facilitates liquid-handling confirmation required for Good Laboratory Practice (GLP) compliance and provides an avenue to track the amount of sample transferred for extraction.The Balance Data Collector (BDC) system was designed as a flexible generic balance tool to be used with Tecan Gemini© and Packard WinPrep® software. The BDC system provides a user interface for balance configuration, a pointer to a file for storing weight data, and an external interface through command-line arguments. BDC is currently used for instrument qualification and sample collection in bioanalytical applications. Instrument qualification includes refining instrument liquid classes and verifying pipetting accuracy and precision. For bioanalytical applications using 96-well plates, BDC collects individual aliquot weights of samples transferred during an assay.The BDC system provides the user with the capability to control a balance via liquid-handling programming platforms such as Tecan Gemini© and Packard WinPrep®. Integration of liquid-handling platforms and BDC reduces the time the scientist must spend recording weight data needed for GLP compliance and can be used to increase accuracy of calculated sample concentrations. 相似文献
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536.
Bruce A. Kimball Jimmy Taylor Kelly R. Perry Christina Capelli 《Journal of chemical ecology》2009,35(12):1461-1470
Four repellents representing different modes of action (neophobia, irritation, conditioned aversion, and flavor modification) were tested with captive white-tailed deer in a series of two-choice tests. Two diets differing significantly in energy content were employed in choice tests so that incentive to consume repellent-treated diets varied according to which diet was treated. When the high-energy diet was treated with repellents, only blood (flavor modification) and capsaicin (irritation) proved highly effective. Rapid habituation to the odor of meat and bone meal (neophobia) presented in a sachet limited its effectiveness as a repellent under conditions with a high feeding motivation. Thiram, a stimulus used to condition aversions, was not strongly avoided in these trials, that included only limited exposures to the repellent. These data support previous studies indicating that habituation to odor limits the effectiveness of repellents that are not applied directly to food, while topically-applied irritants and animal-based products produce significant avoidance. 相似文献
537.
Junguo Liu Jimmy R. Williams Xiuying Wang Hong Yang 《Environmental Modelling & Software》2009,24(5):655-664
Although the EPIC model has been widely used in agricultural and environmental studies, applications of this model may be limited in the regions where daily weather data are not available. In this paper, a stand-alone MODAWEC model was developed to generate daily precipitation and maximum and minimum temperature from monthly precipitation, maximum and minimum temperature, and wet days. A case study shows that the crop yields and evapotranspiration (ET) simulated with the generated daily weather data compare very well with those simulated with the measured daily weather data with low normalized mean square errors (0.008–0.017 for crop yields and 0.003–0.004 for ET). The MODAWEC model can extend the application of the EPIC model to the regions where daily data are not available or not complete. In addition, the generated daily weather data can possibly be used by other environmental models. Associated with MODAWEC, the EPIC model can play a greater role in assessing the impacts of global climate change on future food production and water use. 相似文献
538.
Kevin K. F. Cheung Morris S. Y. Jong F. L. Lee Jimmy H. M. Lee Eric T. H. Luk Junjie Shang Marti K. H. Wong 《Virtual Reality》2008,12(1):17-25
Virtual interactive student-oriented learning environment (VISOLE) is a game-based constructivist pedagogical approach that
encompasses the creation of an online interactive world modeled upon a set of interdisciplinary domains, in which students
participate as “citizens” to take part cooperatively and competitively in shaping the development of the virtual world as
a means to construct their knowledge and skills. FARMTASIA is the first online game designed using the VISOLE philosophy,
encompassing the subject areas of biology, government, economics, technology, production system and natural environment. The
“virtual world” deployed is a farming system covering the domains of cultivation, horticulture and pasturage, situated in
a competitive economy governed by good public policies. The design and implementation of FARMTASIA pursue three vital principles.
The first one is to make the game as realistic as possible so that students can learn in a near-real life environment; the
second one is to inject motivational elements so that students can sustain to learn and acquire various knowledge and skills
with the game; and the third one is to make easy for teachers to conduct various VISOLE facilitation tasks. According to our
exploratory educational study, we show evidentially that positive perceptions and an advancement of subject-specific and interdisciplinary
knowledge appeared among the students who participated in VISOLE learning with FARMTASIA. 相似文献
539.
1 IntroductionTransparent super-hydrophilic self-cleaningTiO, thin films on glass substrates have highpotentialities for practical aPPlications such asmirrors, window glasses, windshields of automobiles, etc. The super-hydrophilic property ofthe surface allows water to spread completelyacross the surface rather than to remain asdroplets, Which malles the surface anti-foggingand easily washing. Recently, there are some research papers abollt the super-hydrOPhilic prOPerty of TiO, coating fi… 相似文献
540.
Jimmy Castillo Alberto Fern ndez Marí a A. Ranaudo S crates Acevedo 《Petroleum Science and Technology》2001,19(1):75-106
The solubility of Furrial asphaltene in toluene was 57g L-1. However, using a new technique, based on the precipitation of this sample by the phenol PNP, we found that a fraction [2], comprising 47% of the asphaltene, is of low solubility. This suggested that this material constitutes the colloidal phase, and the rest acts as the dispersing fraction. This technique allowed the fractionation of asphaltenes in fractions A1, A2, and A3 according to solubility, going from practically insoluble (A1) to low (A2, 1 g L-1) to high (A3, around 57 g L-1). The adsorption isotherms of asphaltenes on glass and silica in toluene consist of a sequence of steps or step-wise adsorption. The first layer or first step is formed by the adsorption of free asphaltene molecules and by small aggregates (aggregation number between 3 and 6) which saturate the glass or silica surface in the usual manner (L-type or H-type isotherms). However, we suggest that the second, third, and other asphaltene layers adsorb sequentially according to the above differences in solubility. The very slow changes with time and the negligible desorption from the surface measured for the above isotherms were interpreted as the effect of packing or the building up of a well packed layer. This would be achieved by the slow formation and rupture of bonds between neighboring molecules at the surface. Thus, molecules with difficulties to pack, adsorbed by a kinetically controlled process, are either rejected or relocated in a thermodynamic controlled process. The above results and ideas were used to improve the models for asphaltene and petroleum colloids and to underscore the importance of surfaces and colloid dispersants in asphaltene precipitation during the production of crude oils. For instance, the results described below suggest that colloids are constituted by a well packed and insoluble asphaltene core, impervious to the solvent, and by a loose packed periphery which, by allowing solvent penetration, keep the colloid in solution. According to this model, desorption of compounds in the above loosely packed periphery, such as the one promoted by a surface, would be the main cause of asphaltene precipitation from crude oils. In this case, solubility reductions caused by pressure drops during oil production would have a minor effect. Also, preliminary number average molecular weights Mn for four asphaltenes, obtained using a new procedure, are presented here. The Mn values obtained ranged from 780 to 1150 g/mol. 相似文献