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41.
Clean Technologies and Environmental Policy - It is a global challenge to achieve sustainable economic growth by improving the environment. The present study discussed the role of the financial...  相似文献   
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The effect of the final morphology and the role of ethylene propylene rubber (EPR) content and (iPP) particle size on the mechanical properties of (iPP/EPR) in situ blends are investigated. The addition of EPR causes a significant improvement in the impact strength of the composites, from 20 kJ/m2 in unthoughned composite iPP to 100 kJ/m2 in iPP/EPR composites containing 50% EPR. Conversely, the tensile strength and the Young's modulus of the blends decrease as the EPR amount increases. The mechanical tensile strength is similar for the composite which have a time of homopolymerization less or equal to 60 min, and a higher value is observed in the case of 100 min. The scanning electron microscopy characterization shows that the larger the iPP particle is, the less the rubber settles on the surface of the high impact polypropylene and the less the final material is resistant to shocks. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44197.  相似文献   
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Pearl millet like other cereals shows qualitative and quantitative deficiency in protein. The main objective of this study was to obtain the food of high nutritive value with high protein content and biological value by supplementing pearl millet, with whey protein. Two levels of whey protein were considered (20% and 25% protein content). Supplemented samples and control were fermented in the presence of starter for 14 h according to the traditional method utilised in Sudan. The pH, crude protein, in vitro protein digestibility (IVPD) and protein fractions of the fermented and supplemented pearl millet were determined at 2‐ h intervals. Supplementation of whey protein resulted in significant increase in protein content compared to the control, i.e. 14.8%, 23.9% and 28.7% for Ashana control (AC), Ashana plus whey protein (20% protein content) (AW1) and Ashana plus whey protein (25% protein content) (AW2), respectively. Fermentation was found to cause a highly significant (P ≤ 0.05) improvement in IVPD for AC, AW1 and AW2. The major protein fraction in the whey protein supplemented doughs was the globulin. This would indicate an improvement in the nutritional quality of pearl millet. Sensory evaluation revealed higher acceptability for whey protein supplemented formulas compared to control.  相似文献   
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In this paper, five typical regions of Algeria where wind is strong enough are selected. These regions usually intended for traditional agriculture are, centred around the towns of Guelma, El Oued, Tindouf, Touggourt and Tamanrasset. To make wind energy conversion available as an alternative energy source for the populations living in such countries, nine types of small and medium wind turbines constructed by American and European manufacturers are studied for their suitability. To account for the wind variations with height, four possible heights of the pylon holding the turbines are considered: 10, 20, 40 and 60 m. In each of the five locations and at each pylon height, wind energy converted by the turbines, is cumulated over the year and computed. Depending on the site and their size, most of these turbines are found to produce about 1000–10,000 MWh of electricity per year at 60 m of altitude and can easily satisfy the electricity need in irrigation and its household applications in rustic and arid regions. A quick glance of the results of the above computation shows that the choice of pylons of 20 m height yields a trade-off between the production of electrical energy and the requirements of economy. Owing to the sporadic wind variations, wind energy conversion systems can only be used as an auxiliary source. In particular, these systems can advantageously be coupled to stand-alone photovoltaic conversion systems in remote locations or connected to the electric mains in urban zones.  相似文献   
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The aim of this study was to provide a detailed analysis of wind energy resources for seawater reverse osmosis desalination (SWRO), in a case study region of Ténès Algeria, by using commercial Wasp software. An economic analysis of the environmental benefits was also done using RETScreen software to give details about financial investment hazards and CO2 emissions reduction. An energy yield and economical analysis was performed of a hypothetical wind farm consisting of 5 wind turbines of type Bonus 2 MW. It was found that wind energy can successfully power a SWRO desalination plant in the case study region.  相似文献   
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In this paper, we study general linear programs in which right hand sides are interval numbers. This model is relevant when uncertain and inaccurate factors make difficult the assignment of a single value to each right hand side. When objective function coefficients are interval numbers in a linear program, classical criteria coming from decision theory (like the worst case criterion) are usually applied to determine robust solutions. When the set of feasible solutions is uncertain, we identify a class of linear programs for which these classical approaches are no longer relevant. However, it is possible to compute the worst optimum solution. We study the complexity of this optimization problem when each right hand side is an interval number. Then, we exhibit some duality relationships between the worst optimum solution problem and the best optimum solution to the dual problem.  相似文献   
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Lubricating greases undergo extensive deterioration under the operation conditions and storage. Hydrocarbon chain is one of the major factors resulting in loss of the base fluid quality by formation of products having negative effects on the physicochemical properties in particular the total acid number and dynamic viscosity. Antioxidants are major ingredients that protect the quality of lubricating grease by retarding oxidation reactions. Accordingly, the aim of this paper is a study on the preparation and evaluation of some compounds which act as antioxidants for prepared lithium lubricating grease. These additives are α-(2-amino-3-cyano-6-pyridyl)o-hydroxyl cinnamic hydrazide (compound I), ethoxymethyl enamino derivative (compound II) and 3-amino-5-hydroxyl-4 phenylazo-1H-pyrazole (compound III).The structure of these compounds has been confirmed using elemental analysis, nuclear magnetic resonance and infrared spectroscopy. On the other hand, lithium lubricating grease was prepared and evaluated according to the National Lubricating Grease Institute (NLGI) and Egyptian Standard (ES). The antioxidant compounds were tested for the prepared grease with concentration 0.1 wt.%. The efficiency of these compounds has been determined using total acid number. It was found that the prepared lithium grease resists oxidation reaction in the presence of these compounds. A correlation between the chemical structure of these compounds and their efficiency as antioxidants additives was discussed. Data showed that the efficiency of these compounds as antioxidants decreases in the order: compound I > compound II > compound III.  相似文献   
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A new type of nanofiltration membranes was synthesized using solution blending polyvinylidine fluoride (PVDF) and poly(styrene-butadiene-styrene) with acid chloride-modified multi-walled carbon nanotubes (MWNTs-COCl) and acid chloride-modified nanotbes-grafted-silver nanoparticles (MWNTs-COCl-Ag). SEM of PVDF/SBS-MWCNTs-COCl-Ag nanocomposite membranes showed polymer-coated Ag particles grafted on the surface. Tensile testing depicted the enhanced mechanical stability of PVDF/SBS-MWCNTs-COCl-Ag membranes around 18.8–22.4 MPa relative to PVDF/SBS-MWCNTs-COCl (10.1–13.3 MPa). 0.1 wt.% MWCNTs-COCl-Ag also enhanced the water permeability of membrane. Moreover, acid chloride-modified MWCNTs and Ag nanoparticles enhanced thermal properties to T0 of 358°C, T10 of 476°C and Tmax around 599°C.  相似文献   
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