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81.
Life often presents us with obstacles to goals and the work arena is no exception. Two studies examined whether dealing with such obstacles promotes creative thought in goal pursuit. In Study 1, thinking about how to reach a goal with (versus without) an obstacle led participants to broaden especially goal‐relevant categories, which suggests that people first and foremost open up to more unusual means when tackling an obstacle. Moving beyond a passive broadening of categories, thinking about how to reach a goal with (versus without) an obstacle in Study 2 also led participants to actively generate more original means. Together these findings suggest that people's basic cognitive responses to obstacles are in the service of goals. Theoretical and organizational implications as well as the role of motivation and emotions are discussed.  相似文献   
82.
The focus of the development of UV-crosslinkable self-adhesive medical products is on one hand directed toward customer-oriented requirements such as tack, adhesion, cohesion, biocompatibility, and permeability for water vapor or air. The customer wants highly tolerable, breathable products, which are also characterized by very good skin and optimal release. On the other hand, the economic targets of medical products manufactures must be considered. Development in the area of UV-crosslinkable acrylic pressure-sensitive adhesives (PSA) for medical application describes the variety of acrylic composition, residue monomers content, quality control of peel adhesion level and repeating during the time, biocompatibility of the acrylic self-adhesive layers and their practical medical application. The new class of unsaturable copolymerizable photoinitiator, such as 4-acryloyloxy benzophenone was used for the synthesis of photoreactive UV-crosslinkable solvent-borne acrylic PSA. The properties of acrylic PSA were determined as well.  相似文献   
83.
84.
Abstract: Obesity and diabetes have led consumers to increasingly seek out products containing low‐calorie sweeteners. In this context, the intense sweeteners, especially plant proteins that interact with the taste receptors, are playing a growing role. Among the sweet‐tasting proteins thaumatin seems the most promising. Production of thaumatin by transgenic plants might be an interesting alternative to the extraction of this product from the natural source. Another possible application of the unusual properties of thaumatin is to produce transgenic plants containing a protein capable of inducing a sweet taste phenotype. The taste of 5 crop species, cucumber, pear, potato, strawberry, and tomato, was improved by expressing the thaumatin II gene under control of the 35S promoter. Only in the case of transgenic cucumber were sensory assessments carried out for several cultivation cycles. Also, processed fruits of transgenic cucumber, as well as fresh‐cut transgenic cucumber salads, were the subject of sensory analysis. Transgenic cucumber expression of the thaumatin II gene resulted not only in sweeter taste, in comparison with the control, but also in higher aroma acceptability. Therefore, the authors of this article have summarized sensory properties of transgenic crops expressing the thaumatin II gene, placing special emphasis on the sensory characteristics of transgenic cucumber. Consumers often perceive disparagingly food deriving from genetically modified (GM) plants, partly because of some concerns about unintended effects. To address such concerns, this article also summarizes the food safety evaluation of transgenic crops expressing the thaumatin II gene. Future research directions are suggested.  相似文献   
85.
Photoreactive solvent‐borne pressure‐sensitive adhesives are not commercially available in the market. The reason for it is that the UV‐initiated crosslinking has sense only in the case of solvent‐free self‐adhesive systems. Investigations conducted in Institute of Chemical Organic Technology have shown that the photoreactive solvent‐borne acrylic PSA are conventional crosslinked solvent‐borne acrylic PSA used as crosslinking agents typical metal chelates as titanium acetylacetonate (TiACA), aluminum acetylacetonate (AlACA) or thermal reactive crosslinker melamine‐formaldehyde resin Cymel 303 clear considered. The main purpose of the investigation was to study the influence of diverse photoinitiators on main properties, such as shrinkage, tack, peel adhesion, and shear strength of solvent‐based acrylic pressure‐sensitive adhesives. The interesting alternative to conventional photoinitiators is unsaturated photoinitiators described in this article. Following unsaturated photoinitiators were used: 4‐acryloyloxy benzophenone, 4‐acryloyloxyethoxy benzophenone, and 4‐acryloyloxybutoxy benzophenone. The influence of the crosslinking agents or crosslinking methods was determined in relation to the reaction time and to the concentration versus adhesion properties. The increase of photoinitiator concentration causes in the decrease of the shrinkage. Increasing the UV dose during the crosslinking of acrylic PSA film leads clearly to better shrinkage resistance. The best results of the lowest shrinkage value of 0.35% were given by using 4‐acryloyloxy benzophenone. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
86.
Janina Kabatc  Katarzyna Jurek 《Polymer》2012,53(10):1973-1980
N,N′-diethylthiacarbocyanine iodide (Cy) with two different compounds acting as co-initiators were used in the three-component photoinitiating systems for free radical polymerization of acrylate monomer. The steady state and time-resolved techniques were used to study the fluorescence quenching by co-initiators, as well as laser flash photolysis to investigate an electron transfer process, that occurs in these photoinitiating system (PIS). To investigate the key factors involved with visible-light activated radical polymerizations involving three-component photoinitiators, we used thermodynamic feasibility and kinetic considerations to study photopolymerizations initiated with thiacarbocyanine dye as a photosensitizer. The Rehm–Weller equation was used to verify the thermodynamic feasibility for electron transfer reaction. Experiments show, that the main interaction between the dye and both co-initiators occurs through its excited singlet state. It was concluded, that the key kinetic factors for efficient visible-light activated initiation process are summarized in two ways: (1) to retard back electron transfer and recombination reaction steps and (2) to use a secondary reaction step to consuming dye-based radical and regenerating the original photosensitizer.Basing on the study, it is known that, there are two possible mechanisms of generation of free radicals, which can start polymerization involving photoreducible series mechanism and parallel series mechanism (photoreducible–photooxidizable series mechanism).  相似文献   
87.
This article describes the photoreactive UV-crosslinkable solvent-borne acrylic pressure-sensitive adhesives (PSA) containing unsaturated copolymerizable photoinitiators and their synthesis. The solvent-borne acrylic PSA were synthesized in ethyl acetate as a solvent, and the copolymerizable photoinitiators type II, known as hydrogen abstractors, were incorporated into acrylic polymer chain during conducted radical polymerization process. The synthesized solvent-borne acrylic PSA containing different unsaturated photoinitiators were investigated to evaluate their relevant and significant properties such as tack, peel adhesion, and shear strength after UV exposure.  相似文献   
88.
We examined the interactive effects of ethnic identification (EI) and race-based rejection sensitivity (RS-race) on institutional outcomes among African American college students. We distinguished between effects on institutional identification on the one hand and academic goal pursuit (e.g., staying in school, grade point average [GPA]) on the other. Supporting the utility of this distinction, we found that EI and RS-race interacted to predict these outcomes differently. Higher EI in combination with higher RS-race predicted reduced identification with the institution (Studies 1, 2, and 3a). This combination, however, did not lead to decreases in GPA over time. Moreover, EI was positively related to intentions to stay in school as well as to GPA increases among those lower in RS-race (Studies 1 and 3b). Implications for understanding identity negotiation vis-à-vis performance in institutional settings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
ABSTRACT:  This review encompasses the binding of volatile flavor compounds by milk proteins in aqueous solutions. The presence of proteins in a food matrix can result in a decrease in aroma perception and in an unpleasant aroma profile, because of binding of the desirable flavor compounds to proteins. Hence, various analytical methods used to measure the extent and the type of binding, and the determination of the binding parameters, are evaluated in this review. The binding of various flavor compounds by individual milk proteins is discussed and compared in terms of their binding affinity for flavor compounds. Furthermore, the influence of temperature and ultra-high pressures on the interactions between proteins and flavors is considered in detail. The implications of protein–flavor binding in the development of protein foods are discussed.  相似文献   
90.
The liquid crystal mixture E7, based on cyanobiphenyl, has been successfully employed to map electric field strength and distribution in AlGaN/GaN high electron mobility transistors. Using a transmitted light image through crossed polarizers the optical response of the liquid crystal deposited onto the surface of the devices was recorded as a function of source–drain bias, Vds. At a critical voltage of 4 V the preferred direction of orientation of the long axes of the liquid crystal molecules in the drain access region aligned with one of the polarizers resulting in reduced transmitted light intensity. This indicates that at this electric field strength molecule orientation in most of the liquid crystal film is dominated by the electric field effect rather than the influence of surface anchoring. The experimental results were compared to device simulations. Electric field strength above the surface at Vds = 4 V was simulated to reach or exceed 0.006 MV/cm. This electric field is consistent with the field expected for E7 to overcome internal elastic energy. This result illustrates the usefulness of liquid crystals to directly determine and map electric fields in electronic devices, including small electric field strengths.  相似文献   
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