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101.
A new DRB3*02 allele (DRB3*0207) was detected in a female Luxembourg Caucasian blood donor by sequence-based typing. The new allele differs from DRB3*0202 by two substitutions in codon 57 resulting in an amino acid change from a charged aspartic acid to a neutral valine. This is the first example of a DRB3 allele pair differing only at codon 57. 相似文献
102.
There is a growing need for supplying repetitive pulsed power loads of increasing magnitudes up to several hundred megawatts or more in areas of radar, lasers, high-energy physics experiments and thermonuclear fusion. The nature of such loads can be expected to be as diverse as their applications. The pulsed power demands and corresponding reactive volt-amperes requirements are undesirable from the frequency and voltage fluctuation standpoint, even for the large utility power systems. Techniques for supplying large dc-pulsed loads from a relatively small size ac generator by means of inductive storage and the capacitor commutated converters are presented. A theoretical basis is provided for analyzing the converters which serve to minimize the effects of pulsed power and corresponding reactive volt-amperes. Energy transfer between the storage inductor and the pulsed load is permitted with minimal loss, at a readily controllable rate including the reversibility of power in case of inductive loads. Use of a simple control scheme is shown to provide a precise load voltage regulation which may be a requirement for certain applications. The greatest use of these circuits would be in supplying loads with pulse durations of a few milliseconds to many seconds or minutes. 相似文献
103.
Animesh Chakrabarti Man Mohan Sharma 《Journal of the American Oil Chemists' Society》1992,69(12):1251-1253
Anhydrous esterification of myristic acid with propylene was carried out in the temperature range of 110–145°C and pressure
from 190–195 psig in the presence of Amberlyst-15 (cation exchange resin) and Filtrol-24 (acid-treated clay) as catalysts.
The product ester, isopropyl myristate finds use in cosmetic and topical medicinal preparations where good absorption through
the skin is desired. Filtrol-24 is the catalyst of choice, and the recommended operating temperature is 130°C with a pressure
of 190 psig. 相似文献
104.
105.
In the present study we report the results obtained on the use of rice bran oil (RBO), a naturally occurring nontoxic oil, and its epoxidized variety (epoxidized RBO, or ERBO) in the compounding and vulcanization of different natural rubber–chloroprene rubber (NR–CR) blends. The processability, cure characteristics, and physical properties of the blends prepared with these oils were compared with those of control mixes prepared with aromatic oil. The optimum cure time and scorch time values of the different blends prepared with these oils were found to be lower than those of the respective control blends prepared with aromatic oil. Evaluation of physical properties of the different experimental blends showed that replacement of aromatic oil with these oils did not adversely affect their physical properties. Because RBO contains a good amount of free fatty acids it was tried as a coactivator in addition to its role as a processing aid. The level of these oils required for the blend preparation was optimized in a Brabender plasticorder. Physical properties such as tensile strength, elongation at break, tear strength, swelling index, and abrasion loss, for example, were evaluated for both experimental and control mixes. Comparison of cure characteristics and physical properties of the blends prepared with aromatic oil and with these oils showed that these oils could be used in place of aromatic oil in the above blends. It is also to be noted that aromatic oil is of petroleum origin and is reported to be carcinogenic. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 4084–4092, 2003 相似文献
106.
T. R. Vijaybabu T. Ramesh Suman Pandipati Sujit Mishra G Sridevi C Pradeep Raja Rhoda Afriyie Mensah Oisik Das Manjusri Misra Amar Mohanty Karthik Babu NB 《大分子材料与工程》2023,308(7):2300001
The lifespan and the performance of flexible electronic devices and components are affected by the large accumulation of heat, and this problem must be addressed by thermally conductive polymer composite films. Therefore, the need for the development of high thermal conductivity nanocomposites has a strong role in various applications. In this article, the effect of different particle reinforcements such as single and hybrid form, coated and uncoated particles, and chemically treated particles on the thermal conductivity of various polymers are reviewed and the mechanism behind the improvement of the required properties are discussed. Furthermore, the role of manufacturing processes such as injection molding, compression molding, and 3D printing techniques in the production of high thermal conductivity polymer composites is detailed. Finally, the potential for future research is discussed, which can help researchers to work on the thermal properties enhancement for polymeric materials. 相似文献
107.
G. Vijaya Lakshmi N. Chitti Babu P. V. Ravi Kumar D. Subba Rao 《Chemical Engineering Communications》2013,200(4):463-480
Most plant materials are freely and abundantly available and can be used for the removal of heavy metals from effluents. This study investigates the effects of equilibrium, kinetic, and thermodynamic parameters on biosorption of Co(II) ions onto the plant source Erythrina variegata orientalis leaf powder. The biosorption studies are carried out in a batch process. A significant increase in percentage removal of Co(II) is observed as pH value is increased from 2 to 5 and the percentage removal is maximum at pH = 7. The maximum sorption capacity is 8.3 mg/g in the range of variables investigated. The experimental data are well represented by Freundlich and Langmuir isotherms indicating favorable biosorption. The biosorption follows second-order kinetics. The biosorption is exothermic, irreversible, and spontaneous. 相似文献
108.
Pillai Mohan Aswathy Jayakumari Babu Anooja Upendran Syamaprasad 《Journal of the American Ceramic Society》2013,96(4):1176-1180
Polycrystalline samples of NdFeAsO1?xFx (Nd1111) with x = 0, 0.1, 0.2, 0.3, and 0.4 were synthesized using a solid‐state method at ambient pressures. A maximum transition temperature (TC) of 52.0 K and a JC of 1050 A/cm2 at 12 K were observed for x = 0.3 and 0.4, respectively. The transport and magnetic properties observed for each stoichiometry have remarkable correlation with their corresponding structural and microstructural aspects. Moreover, the superconducting properties exhibited in this material, processed at a relatively low temperature of 1000°C, are competitive as compared to the existing reports wherein high pressures/temperatures are inevitable. 相似文献
109.
Micromechanical modeling of hybrid composites 总被引:1,自引:0,他引:1
The main aim of this work is to study the effective elastic modulus of hybrid composites through micromechanical modeling. The micromechanical framework based on the generalized method of cells has been employed for this study. The predictions based on the present model are compared with an assortment of experimental and other theoretical predictions. The effect of two types; sequential mode and mixed mode of filler additions on the effective elastic modulus of the hybrid composite are studied. Moreover, the effect of other microstructural parameters such as the concentration, shape and aspect ratio of fillers in altering the hybridization effects are also investigated. 相似文献
110.
Hydrotreating of Maya heavy crude oil over high specific surface area CoMo/TiO2–Al2O3 oxide supported catalysts was studied in an integral reactor close to industrial practice. Activity studies were carried out with Maya crude hydrodesulfurization (HDS), hydrodemetallization (HDM), hydrodenitrogenation (HDN), and hydrodeasphaltenization (HDAs) reactions. The effect of support composition, the method of TiO2 incorporation, and the catalyst deactivation are examined. Supported catalysts are characterized by BET specific surface area (SSA), pore volume (PV), pore size distribution (PSD), and atomic absorption. It has been found that sulfided catalysts showed a wide range of activity variation with TiO2 incorporation into the alumina, which confirmed that molybdenum sulfided active phases strongly depend on the nature of support. The pore diameter and nature of the active site for HDS, HDM, HDN, and HDAs account for the influence of the large reactant molecules restricted diffusion into the pore, and/or the decrease in the number of active sites due to the MoS2 phases buried with time-on-stream. The textural properties and hysteresis loop area of supported and spent catalysts indicated that catalysts were deactivated at the pore mouth due to the metal and carbon depositions. The atomic absorption results agreed well regarding the textural properties of spent catalysts. Thus, incorporation of TiO2 with γ-Al2O3 alters the nature of active metal interaction with support, which may facilitate the dispersion of active phases on the support surface. Therefore, the TiO2 counterpart plays a promoting role to HDS activity due to the favorable morphology of MoS2 phases and metal support interaction. 相似文献