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131.
Glucose oxidase (GOx)-based amperometric enzyme electrodes have been the target of substantial research. In this study, new amperometric biosensor for determination of glucose was developed. GOx enzyme was immobilized at bovine serum albumin via entrapment method. For this reason, the optimum conditions of Pd–Au NPs/GOx/C-modified glassy carbon electrode were determined. The electron is directly transferred from glucose to the electrode via the active site of the enzyme. The absence of mediators is the main advantage of such third-generation biosensors. The resulting materials were characterized employing scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction. In addition, the effects of glucose concentration, scan rate, temperature, electroactive interference, stability, reusability of the biosensors were discussed. The applicability to blood analysis was also evaluated. The biosensor has a limit of detection for the determination of glucose 0.0014?mM.  相似文献   
132.
Ethylene propylene dine monomer (EPDM) was blended with both ground tire rubber (GTR) and high-density polyethylene (HDPE) prepared at different ratios and then exposed to gamma and ultraviolet radiations. The mechanical, physical, and thermal properties were investigated with respect to the kind of irradiation and blend compositions. A scanning electron microscope was also used to examine the morphology of the irradiated blends. The blend of ratios (75/25/50) exhibited the best mechanical and physical properties after gamma irradiation, so this blend was taken as an example to be exposed to the UV radiation. The results indicated an improvement in the mechanical and physical properties for the blends exposed to gamma irradiation, but the mechanical and physical properties examined after UV irradiation were slightly affected. Scanning electron microscope measurements indicated the improvement in the homogeneity and the compatibility after irradiation, particularly in case of gamma radiation.  相似文献   
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134.
Journal of Materials Science: Materials in Electronics - In the present work, we have explored the physical properties of ZnFe2?xCoxO4 (0?≤?x?≤?0.06)...  相似文献   
135.
136.
We report herein that copolymers containing glycidyl methacrylate (GMA) with acrylonitrile (AN) units were synthesized by free radical solution polymerization technique using benzoyl peroxide as a free radical initiator and 1,4‐dioxane as a solvent at 70°C. The copolymerization behavior was studied in different composition with the mole fractions of GMA ranging from 0.20 to 0.80 in the feed and under 10% copolymer conversion. The copolymers were characterized by Fourier transform infrared spectroscopy, gel permeation chromatography, and scanning electron microscopy techniques. The thermogravimetric analysis of the copolymers suggest an overall decrease in the thermal stability of the copolymer with decreasing content of GMA in the copolymers. Thermal decomposition activation energies are calculated by the Ozawa method. The copolymer composition was determined by the application of elemental analysis method. The monomer reactivity ratios were estimated by the application of conventional linearization methods, such as Kelen–Tudos (K‐T), Fineman–Ross (F‐R) methods, and a nonlinear error in variable model (RREVM) method using a computer program, and all results were discussed and compared with the literature.  相似文献   
137.
Hemicellulose is a valuable component of agro‐food industrial wastes and used in various areas such as drug manufacture and food industry for encapsulation and emulsification. In this study, effects of raw material type, particle size, and extraction conditions (alkaline concentration, temperature, time) and methods (direct alkaline extraction, alkaline extraction after component removal and acidic extraction method) on hemicellulose yields were investigated. Sugar beet pulp and corn wastes were used as raw material. The alkaline method resulted in 40.2% pure extracts, while the acidic method gave only 27.4% purity in the same extraction conditions. The optimal extraction conditions were found as 30 °C temperature, 10% alkali (NaOH) and 24 h time (64.3%). It was also observed that removal of constituents such as fat, protein, starch and soluble sugar increased the purity of hemicellulose from 40.2% to 58.2% at the same conditions. The results indicated that using both low alkaline concentration and low temperature allows to recover higher‐quality extracts.  相似文献   
138.
Pattern Analysis and Applications - Due to the rapid increase in exchange of text information via internet network, the security and the reliability of the digital content has become a major...  相似文献   
139.
This study aims to detect aflatoxins (AFs) in dairy cow feed, milk and milk products using a high-performance liquid chromatography coupled with fluorescence detection (HPLC-FLD) method. All the validation parameters met the method performance criteria of the European Union. The samples comprised 76 dairy cow feeds and 205 milk and milk products (including yoghurt and yoghurt-based beverage, ayran). AFs were present in 26.3% of the feed samples. Two feed samples exceeded the maximum limit (ML) of 5 µg kg?1 for AFB1 as established by the EU. Nineteen milk samples (21.1%) contained aflatoxin M1 (AFM1) of which three exceeded the EU ML of 0.05 µg l?1. In addition, only two yoghurt samples and one ayran sample contained AFM1, but the levels were lower than the EU ML.  相似文献   
140.
This study revealed the effect of cam setting and number of yarn ply on air permeability and bursting strength of weft-knitted fabrics from glass yarn. Change in cam setting from loose to tight level increased fiber content, and stitch-density; while it decreased loop length. Fabrics with 3-ply yarn exhibited higher fiber content; lower stitch-density; and longer loop length than fabrics with 2-ply yarn. Cam setting showed more pronounced effect on physical properties of fabric than number of yarn ply. Fabrics knitted via tight cam setting level exhibited less air permeability, and higher bursting strength than fabrics knitted via loose cam setting. Fabrics from 3-ply yarn showed less air permeability and higher bursting strength than fabrics from 2-ply yarn. Loop length, wale density, and fiber content were determined as the most effective physical properties on permeability and bursting strength. A negative correlation was detected between air permeability and bursting strength.  相似文献   
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