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121.
In this study, the fat phase of chocolate samples which contained cocoa butter from Ghana and cocoa butter equivalent (CBE) of moderate hardness was analyzed. Physical properties and shelf life of chocolate depend on the fat phase behavior as well as the amount and composition of added CBE. The laboratory-made chocolate samples were tempered at three different pre-crystallization temperatures (25, 27 and 29 °C), with three different concentrations of CBE, amounting to 3, 5 and 7 %, calculated on chocolate. The color and other physical attributes of chocolate samples were investigated by the following analytical methods: thermoreographic measurement, solid fat content (SFC) of chocolate, Blooming test (thermo-cycle test 32/20 °C) and color measurement. It was found that using CBE of moderate hardness did not change the melting properties of chocolate in relation to the investigated cocoa butter from Ghana (of moderate hardness). It was found that all three applied temperatures of pre-crystallization are optimum for the chocolate mass with the addition of the investigated CBE under the given measurement conditions. At all these temperatures, the chocolate had excellent fat bloom resistance.  相似文献   
122.
The oscillatory and chaotic dynamics of MIMO cascade connected nonlinear systems are analyzed in this paper. For that purpose the known theorems of limit sets existence in appropriate nonlinear discrete systems are used. Control of spatial limit sets and spatial chaos appearance in MIMO cascade connected nonlinear systems using modified Pyragas method is also analyzed. The results are illustrated by examples and confirmed with simulations.  相似文献   
123.
A series of novel thermoplastic elastomers based on ABA‐type triblock prepolymers, poly[(propylene oxide)–(dimethylsiloxane)–(propylene oxide)] (PPO‐PDMS‐PPO), as the soft segments, and poly(butylene terephthalate) (PBT), as the hard segments, was synthesized by catalyzed two‐step melt transesterification of dimethyl terephthalate (DMT) with 1,4‐butanediol (BD) and α,ω‐dihydroxy‐(PPO‐PDMS‐PPO) (M?n = 2930 g mol?1). Several copolymers with a content of hard PBT segments between 40 and 60 mass% and a constant length of the soft PPO‐PDMS‐PPO segments were prepared. The siloxane‐containing triblock prepolymer with hydrophilic terminal PPO blocks was used to improve the compatibility between the polar comonomers, i.e. DMT and BD, and the non‐polar PDMS segments. The structure and composition of the copolymers were examined using 1H NMR spectroscopy, while the effectiveness of the incorporation of α,ω‐dihydroxy‐(PPO‐PDMS‐PPO) prepolymer into the copolyester chains was controlled by chloroform extraction. The effect of the structure and composition of the copolymers on the transition temperatures (Tm and Tg) and the thermal and thermo‐oxidative degradation stability, as well as on the degree of crystallinity, and some rheological properties, were studied. Copyright © 2006 Society of Chemical Industry  相似文献   
124.
Blindness to response-compatible stimuli is the finding that targets are identified less accurately when presented during the planning or execution of a congruent response (e.g., right arrow presented during a right keypress) versus an incongruent response (e.g., right arrow presented during a left keypress). Accounts of this effect suggest the planning and execution of a response are critical to its observation. Five experiments investigated whether a blindness effect would be observed in the absence of a planned response. Results suggest that a planned response is not necessary to observe a content-specific blindness effect and that the blindness effect may actually comprise both an action-related component and a symbolic component that is distinct from the action-planning system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
125.
Action-compatible blindness refers to the finding that target stimuli are perceived less frequently if they are presented during the planning or execution of a compatible action (e.g., a left arrow presented during a left manual key press) than during an incompatible action (J. Müsseler and B. Hommel, 1997 a, b). We investigated the effect of lengthening the response execution phase in the action-compatible blindness paradigm by requiring subjects to tap a response key once or three times on the assumption that tapping three times would increase the duration of the execution phase of the response. Prior research (e.g., B. Stevanovski et al (2002); P. Wühr and J. Müsseler, [2001]) has shown that larger blindness effects are observed for targets presented during the execution phase of a response than after the response has been made. We investigated whether a larger blindness effect would be observed in the three-tap condition than in the one-tap condition, or whether lengthening the duration of the response would extend the time course of the blindness effect. Neither of these possibilities was supported by the data irrespective of whether the number of taps to be made was blocked or mixed within a block of trials. The results are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
126.
The implementation of ICT (information and communication technologies) into the educational process is becoming a reality in the 21st century. Today's students grow up with technology. To keep their attention, scientific problems should be solved through visualization, which is made possible using ICT in the educational process. In the modem educational process, students still have difficulties in learning science concepts. Also, it is a very common problem that students cannot apply mathematical language and concepts into other science areas such as physics, engineering, etc. For example, students start learning about vectors in mathematics in secondary school. Vectors are very important because they have a wide area of applications especially in physics, engineering and navigation to represent forces, tension, velocity, etc.. Using the free mathematical software GeoGebra, a simulation of using vectors in these areas is made. It will be shown that such simulations increase students' interest, keep their attention, and make this knowledge more real and more understandable and connected to the physical world and thus more applicable to their other studies.  相似文献   
127.
128.
The effects of country of origin on New Zealand consumers' perceptions of food product attributes, including nutritional value, safety, quality, taste, price, value for money, and environmental impact were investigated. A random population survey of shoppers (n = 315) compared attributes of food products from six countries to those produced in New Zealand. Principal component analyses were used to identify underlying dimensions of attributes and overall product perceptions. Subsequently, stepwise regression analyses were used to assess predictors of these perceptions. Consumers' perceptions differed according to product-related and intrinsic consumer factors. The penetration of imported products in the market, the level of economic development of the exporting country, and the similarity of the culture of the exporting country were key product-related influences. Ethnocentrism, consumers' interest in foreign cultures, income, education, age and sex were the main consumer factors which influenced their perceptions of foreign food products.  相似文献   
129.
Wholegrain and refined (white) wheat breads were prepared with the addition of high-oleic sunflower seed at various levels (8%, 12%, 16% flour basis). The nutritive value of breads was determined by measuring the chemical composition, including the mineral content, the fatty acid composition (saturated, monounsaturated, polyunsaturated, linoleic and linolenic acids) and the contents of tocopherols (α-, β-, γ-, δ-). The obtained data were used to estimate the intakes of nutrients and compare them to the dietary reference intakes (DRIs). The breads made with the addition of sunflower seed were sensorially acceptable, containing significantly more tocopherols, fat, essential fatty acids, crude fibre, copper and zinc. It was estimated that wholegrain supplemented breads would contribute to the corresponding DRIs in the range 33.7–40.8% (adults) for copper and 4.7–18.4% (males), i.e. 6.4–25.3% (females) for zinc, 18.3–26.8% (males), i.e. 25.9–37.9% (females) for linoleic (omega-6) acid, 7.4–7.6% (males), i.e. 10.7–11.0% (females) for alpha-linoleic (omega-3) acid.  相似文献   
130.
Arsenic, well known of its toxicity, is present in potable water in many areas in the world, as well as in underground water used for water supply in Vojvodina, a region in Serbia. Its removal from raw water is necessary before distribution. In this work two methods of arsenic removal from water are compared. First method is water ozonation by introducing ozone in water and then filtration. Second method is treatment of water in plasma reactor and then filtration. High efficiency of the second method was confirmed by low concentration of arsenic in filtrate (below detection limit).  相似文献   
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