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1.
The objective of this study was to determine the effect of complexation of oxidised starch with mineral elements on its physicochemical properties. Corn starch was oxidised with sodium hypochlorite and, afterwards, modified with ions of potassium, magnesium and iron. Thus, native and modified starches were analysed for: contents of mineral elements, colour parameters (L*a*b*), water binding capacity and solubility in water at temperature of 60 and 80 °C. Thermodynamic characteristics of gelatinisation by DSC, molecular weight distribution by GPC, intrinsic viscosity and pasting properties by RVA were studied. The efficiency of incorporation of metal ions into oxidised corn starch was about 30%, 20% and 20% for potassium, magnesium and iron ions, respectively. The complexation with potassium ions caused the greatest changes in the molecular weight distribution and the intrinsic viscosity of starches and viscosity of starch pastes. Only modification of starch with iron ions affected the colour parameters of the starch. Incorporation of metal ions into starch resulted also in changes in its water binding capacity and solubility in water.  相似文献   
2.
Ready-to-drinks (RTDs) are composed of an alcoholic component and a soft-drink base and are primarily consumed by a youth market. The authors explored whether liking and experience with an RTD soft-drink base predicts liking for the RTD. Participants (N=350) from ages 12 to 30 years sampled 3 RTDs and their respective soft-drink and alcoholic components. For milk- and fruit-based RTDs, liking for and familiarity with their soft-drink base was the best predictor of liking for and familiarity with the RTD itself. For the Coke-based RTD, familiarity with and liking for bourbon best predicted familiarity with and liking for the RTD. All of these effects were consistent across blind and nonblind testing. The authors' results suggest that where there is perceptual similarity between the RTD and its soft-drink base, these beverages may provide an easy transition into alcohol consumption for novice drinkers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
This paper reports how the study of formal logical reasoning provides insight into more everyday types of reasoning, such as that involved in language comprehension. Both of these types of cognition are thought to involve the use of mental models, and so it is reasonable to think that the cognitive operations needed for formal logical reasoning would be involved in everyday reasoning as well. We focused on three aspects of formal reasoning: (a) the integration of information into a common mental model, (b) the drawing of inferences, and (c) the coordination of alternative possibilities. We were able to show that the integration and inference components were related to narrative comprehension processes, but the coordination of alternative models was not. Thus, there is evidence for some overlap in the mental processes used in formal and everyday reasoning. This further justifies the study of formal logical reasoning as a window into certain types of everyday reasoning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
The original Smoking Consequences Questionnaire (SCQ; T. H. Brandon & T. B. Baker, 1991) measured college students' outcome expectancies for cigarette smoking. A version (SCQ-Adult) was needed for assessing expectancies in more typical, older, nicotine-dependent smokers. Two separate versions of the SCQ were developed and compared. Tests of construct validity provided greater support for the version comprising probability items over the version comprising subjective expected utility items. As expected, principal components analyses revealed a greater number of factors than the original SCQ suggesting that expectancies become more specific with smoking experience. All scales showed good reliability. Over the course of smoking cessation treatment, expectancies became less positive, especially for abstaining participants. Other validity tests also tended to be consistent with research on alcohol expectancies and with contemporary models of drug outcome expectancies. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
5.
A very simple algorithm for computing all k nearest neighbors in 2-D is presented. The method does not rely on complicated forms of tessellation, it only requires simple data binning for fast range searching. Its applications range from scattered data interpolation to reverse engineering.  相似文献   
6.
Advances in distributed architectures and the Internet have had a strong influence on the use of component technologies. The authors discuss the organizational and technical requirements for an effective and economically viable component-based approach.  相似文献   
7.
The portability of software has become a major commercial issue in recent times. Such portability does not come easily, as few if any computer languages are really portable in practice. An additional complicating factor, especially in the commercial environment, is that the resulting software must be efficient. This paper describes the design and successful implementation of a 500,000+ line portable FORTRAN 77 package for the processing of seismic data. The package exhibits demonstrably high efficiency on a wide variety of machines from minicomputers to the largest supercomputers. Experiences gained during this exercise throw much light on the integration of the various thought processes which occur during the software engineering cycle, especially the notion of locality.  相似文献   
8.
9.
Over a 2-year period eight patients underwent percutaneous fluoroscopic fixation of their acetabular fractures. Average patient age was 43 and mean ISS was 27. Mean blood loss was less than 100 ml. There were five transverse fractures, one affecting both columns, one anterior column-posterior hemitransverse and one T-type fracture. There were two ipsilateral femoral and two ipsilateral tibial fractures. Mean follow-up was 15 months. Three broad patient groups were identified. One patient died, one was lost to follow-up, four had full range of motion of the affected hip, one had good range with Brooker II heterotopic ossification and one was wheelchair-bound with Brooker IV heterotopic ossification. The technique, which requires only cannulated screws and fluoroscopy, is described.  相似文献   
10.
Dentinogenesis is being used as a model for understanding the biomineralization process. The odontoblasts synthesize a structural matrix comprised of Type I collagen fibrils which define the basic architecture of the tissue. The odontoblasts also synthesize and deliver a number of dentin-specific acidic macromolecules into the extracellular compartment. These acidic macromolecules may be involved in regulating the ordered deposition of hydroxyapatite crystals within the matrix. AG1 is the first tooth-specific acidic macromolecule to have been cloned and sequenced. To identify which cells of the rat incisor pulp/odontoblast complex were responsible for synthesis of AG1, in situ hybridization was used. Digoxigenin labeled sense and anti-sense AG1 riboprobes were prepared. The AG1 mRNA was found to be expressed in the mature secretory odontoblasts. Neither pulp cells nor pre-odontoblasts showed any staining with the anti-sense probes. Chromosomal localization studies placed the AG1 gene on mouse chromosome 5q21, in tight linkage with Fgf5. AG1 has been renamed Dmp1 (dentin matrix protein 1) in accordance with present chromosomal nomenclature. Mouse 5q21 corresponds to the 4q21 locus in humans. This is the locus for the human tooth mineralization disorder dentinogenesis imperfecta Type II (DI-II). These data suggest that the Dmp1 gene is involved in mineralization and is a candidate gene for DI-II.  相似文献   
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