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121.
The effects of 0, 1.0, 2.0 and 4.0 (x 10?3 M) α-, γ- or δ-tocopherol on chlorophyll b photosensitized oxidation of soybean oil in methylene chloride were studied by peroxide values and headspace oxygen. As concentrations of tocopherols increased, peroxide values decreased and headspace oxygen increased (P < 0.05). At 1.0 × 10?3 M, α-tocopherol showed highest antioxidant effect, γ-tocopherol second and then δ-tocopherol. α- and -γ-Tocopherols had similar effects and δ-tocopherol had lower effect at 2.0 × 10?3 M (P < 0.05). However, the three tocopherols were not different (P > 0.05) at 4.0 × 10?3 M. α-Tocopherol quenched singlet oxygen to reduce the photosensitized oxidation of oil. The quenching rate constants of α-tocopherol were 2.7 × 107M?1sec?1 by peroxide value and 2.6 × 107 M?1sec?1 by headspace oxygen. 相似文献
122.
Synthesis of LiNiO2 cathode by the combustion method 总被引:1,自引:0,他引:1
MYOUNGYOUP SONG IKHYUN KWON HUNUK KIM SUNGBO SHIM DANIEL R. MUMM 《Journal of Applied Electrochemistry》2006,36(7):801-805
To determine optimum conditions for the synthesis of LiNiO2 by the combustion method, syntheses were carried out in air and under oxygen at various calcination temperatures and for different times. The electrochemical properties of the prepared samples were then investigated. The optimum conditions are preheating at 400 °C for 30 min in air in the mole ratio of urea to nitrate 3.6 and calcination at 750 °C for 36 h under O2. The LiNiO2 synthesized under these conditions had a first discharge capacity of 189 mAh g−1 at 0.1 C-rate and relatively good cycling performance. This sample has a larger value of I
003/I
104 (smaller cation mixing) and a smaller R-factor (larger hexagonal ordering). Cycling performance was investigated in various voltage ranges. The first discharge capacity increased as the upper limit of the voltage range rose. The first discharge capacity was small but cycling performance was good when the sample was cycled in the voltage range with the lowest upper limit. 相似文献
123.
Shear stress of Alaska pollock surimi gels with and without beef plasma protein (BPP) increased as heating rate decreased, but shear strain was unaffected. An increase in shear stress was accompanied by an increase of cross-linked myosin heavy chain. Slow heating rates increased proteolysis in Pacific whiting surimi as shown by degradation of myosin heavy chain and low shear stress and shear strain. Proteolysis of whiting surimi was lessened by BPP to a greater extent at rapid heating rates (20 and 30°C/min) than at slow heating rates (1 and 5°C/min). 相似文献
124.
Starch noodles were prepared using potato starch from 8 genotypes, mung bean starch, mung bean-potato starch blends, and sweet potato starch. The cooking quality of noodles from selected potato starches compared well with commercial starch noodles. Of the unblended potato starches, Mainechip exhibited cooking quality similar to commercial starch noodles with respect to cooking loss, cooked weight, and ?rmness. Appearance and texture of starch noodles from three genotypes (E55-35, Mainechip, and Shasta) were evaluated by a trained sensory panel. Noodles made from unblended potato starches had higher glossiness and transparency than those from other starches. Noodles from both un-blended and blended Mainechip starch had the highest press and elasticity. 相似文献
125.
Four anionic trypsins, tentatively labeled trypsin A, B, C, and D, isolated from crayfish hepatopancreas, had high casein activity between pH 5.5 and 10.0. Temperature optima for hydrolysis of casein were 45°C for A and B, and 50°C for C and D. Trypsin D had the highest substrate turnover number (Vmax) for casein reaction compared with the other trypsins at pH 6.8. Trypsins A and D had higher activities against myofibrilla and sarcoplasmic proteins from crayfish tail meat than did B and C. Results suggested that trypsins A and D are important in development of mushiness in crayfish tail meat compared with other trypsins present. 相似文献
126.
Characterization and Food Application of an Amperometric Needle-Type L-Lactate Sensor 总被引:1,自引:0,他引:1
There have been increasing needs for biosensing in the food industry because it is accurate, rapid and efficient. A needle-type L-lactate sensor with a three-layer membrane system which uses lactate oxidase as the biological component was prepared. The sensor had an optimum pH around 9–10 and an optimum temperature at 45 C. The current response was stable over 40 days and specifically responded to L-lactic acid. The sensor gave accurate L-lactate measurements in kimchi and yogurt of 187.4 ± 4.1 and 734.1 ± 34.5 mg/dL, similar to those of a spectrophotometric L-lactate kit. 相似文献
127.
The changes in the size and shape of soybean protein bodies in different solvent systems were observed, and their influence on hydrodynamic properties in solutions was investigated by capillary viscometer. The intrinsic viscosity of the isolated protein bodies varied with the type of dispersion media; 0.036 cm3/g in CCI4-benzene solution, 0.355 cm3/g in 50% glycerol-water mixture, 0.574 cm3/g in water at pH 7, and 1.18 cm3/g in the aqueous solution at pH 12. The hydration of the protein bodies in different dispersion media was estimated by Oncley's method and Mooney's method. The estimated degree of hydration agreed well with the swelling of the protein bodies as observed by microscope. 相似文献
128.
Statistical Evaluation of Data for Detecting Adulteration of California Navel Orange Juice 总被引:2,自引:0,他引:2
CARL E. VANDERCOOK JOSÉ L. NAVARRO DORA C. SMOLENSKY DENNY B. NELSON GARY L. PARK 《Journal of food science》1983,48(2):636-640
Compositional data from California early-, mid-, and late-season navel orange juice, concentrate and two-stage pulpwash were analyzed by various statistical techniques (ratios, regression, chi-square, Linear combination, and discriminant analysis) for detecting adulteration. These techniques were evaluated according to applicability for detecting three types of adulteration: (1) addition of sugar and/or citric acid, (2) addition of excess or unauthorized pulpwash, and (3) addition of other constituents intended to mask the dilution. Most parameters were significantly affected by time of harvest following commercial maturity. Two-stage pulpwash showed small but significant differences from corresponding single strength juice. Product differences were of about the same magnitude as the differences due to harvest date. 相似文献
129.
J. PARK 《Coloration Technology》1968,84(12):601-603
The evolution of techniques for the piece dyeing of tufted carpets is discussed. Most of the development work was carried out on nylon and the piece dyeing of nylon tufted carpets is now well established. The application of the method to viscose rayon, polyester and some other fibres is discussed. Only a small number of dyes are required for each fibre to give a wide range of dyeings of adequate fastness properties. 相似文献
130.