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21.
以聚乙二醇辛基苯基醚(OP)为表面活性剂,甲基丙烯酸甲酯(MMA)为油相构筑的反相微乳液合成纳米Ag Cl粒子,然后通过微乳液聚合制备Ag Cl/PMMA复合胶乳。利用紫外-可见吸收光谱(UV-vis)和透射电镜(TEM)研究微乳液中表面活性剂浓度(cop)、水相中盐浓度(csalt)对纳米Ag Cl粒子的形成及形貌影响,结果发现合成的Ag Cl粒子近似球状,粒径在5 nm左右;在反相微乳液中随cop、csalt的增加,形成的纳米Ag Cl粒子数增多、平均粒径有所减小。Ag Cl/PMMA复合胶乳对大肠杆菌表现出明显的抗菌活性。通过反相微乳液及其聚合技术制备包含有纳米Ag Cl的复合胶乳,方法简便、易于放大,所制备的Ag Cl/PMMA复合胶乳作为抗菌剂具有良好的应用前景。 相似文献
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针对辽河油田注水区块现有颗粒类深部调驱堵剂耐温、抗剪切性能差,成胶强度低,有效期短,压力提升幅度有限等问题,采用丙烯酰胺与天然橡胶胶乳、乙烯基吡咯烷酮通过自由基共聚,经胶体干燥、造粒得到具有良好柔韧性和粘弹性能的柔性凝胶颗粒,并确定了最佳聚合反应条件:单体浓度30%,丙烯酰胺:天然橡胶胶乳:乙烯基吡咯烷酮质量比为1:0.8:0.3,交联剂浓度0.05%,引发剂(甲醛合次硫酸氢钠与过硫酸铵质量比为1:2)浓度0.6%,聚合反应温度65℃。同时确定了用于悬浮凝胶颗粒的凝胶配方体系:聚合物800 mg/L、交联剂400 mg/L、稳定剂80 mg/L,得到了凝胶颗粒现场应用的合理粒径中值为2 mm,最佳使用浓度范围1%~3%。现场试验结果表明:凝胶颗粒对调驱压力提升作用明显,具有很高的可行性和实用性,为注水区块稳油控水提供了有力的技术保障。 相似文献
25.
Previous attempts to use polylactide (PLA) latex particles and nanofibrillated cellulose (NFC) in papermaking processing have been limited to low NFC content. In the present study, a bionanocomposite material was successfully produced using a PLA latex and NFC. The components were mixed using a wet mixing method and bionanocomposite films were made by filtration followed by hot pressing. In composite materials, the dispersion of the reinforcing component in the matrix is critical for the material properties. Biopolymers such as PLA are non-polar and soluble only in organic solvents; NFC is, however, highly hydrophilic. By utilizing latex, i.e., an aqueous dispersion of biopolymer micro-particles, wet mixing is possible and the problem of aggregation of the hydrophilic nanocellulose in organic solvent is avoided. The properties of the resulting NFC/PLA latex bionanocomposite films were analyzed. Thorough blending resulted in good dispersion of the reinforcing component within the matrix. Adding increasing amounts of NFC improved the Young's modulus, tensile strength, and strain at break of the bionanocomposite material. The increase in the tensile properties was linear with increasing NFC content as a result of the good dispersion. The NFC also improved the thermal stability of the bionanocomposite material. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
26.
Jirapornchai Suksaeree Prapaporn Boonme Wirach Taweepreda Garnpimol C. Ritthidej Wiwat Pichayakorn 《Chemical Engineering Research and Design》2012
The nicotine transdermal patches (NTPs) are available used for smoking cessation; however, they still should be developed for high efficacy and low cost. In this study, deproteinized natural rubber latex (DNRL) blended with hydroxypropylmethyl cellulose (HPMC) and dibutylphthalate (DBP) were used as matrix membrane for nicotine (NCT) delivery. Several techniques, i.e., FT-IR, XRD, DSC, and SEM were used to characterize the compatibility of each ingredient in the blended patches. A backing layer was used to protect NCT from volatilization. Five different types of backing layer were evaluated for their effects on in vitro release and skin permeation of NCT from the formulated matrix membranes. The backing layer with highest moisture vapor transmission rate (MVTR) and lowest oxygen transmission (OT) supposed to give higher NCT release and skin permeation due to increasing of skin hydration and its occlusive effect. The kinetic of in vitro release and permeation was demonstrated the monophasic slow release pattern which confirmed by first order and zero order kinetics, respectively. Therefore, the backing layer could be appropriated and used conveniently in the preparation of NTPs. 相似文献
27.
《国际聚合物材料杂志》2012,61(3-4):131-141
Abstract Materials with unique complex of the properties of elasticity and tensile strength processed from the natural rubber latex (NRL) were modified to improve their blood compatibility. ESCA, ATR-IR, UV-spectroscopy and other methods were used for appraisement of the grade of modification, structure and properties of material. Thromboresistancy was studied in in vivo and ex vivo tests. It was shown that blood compatibility is raised after thorough purification of the material from non-rubber components by means of two-stage extraction changing the physical-chemical parameters of the surface. Two different principles were used in the process of modification: 1) coating by thin polyurethane (PU) coverings with improved thromboresistant properties-thus the problem of providing high adhesion interaction of covering with the latex base was solved; 2) heparin surface immobilization-higher efficiency of modification of latex material in gel-form without preliminary protein adsorption was shown. Modification allows to increase blood compatibility of the latex materials preserving at the same time their elasticity and tensile strength. 相似文献
28.
Stepan Podzimek Hedvika Zgoni Peter Bohacik Jaromir Snuparek 《Polymer-Plastics Technology and Engineering》2016,55(13):1365-1372
In this paper, organic asymmetric flow field flow fractionation coupled to a multi-angle light scattering detector is presented as a very efficient tool for the characterization of copolymers prepared by emulsion polymerization. The molar mass distribution and the extent of branching of styrene–acrylate copolymers have been compared with corresponding copolymers of methyl methacrylate. It has been found that the presence of acrylate monomer results in the increase of molar mass and formation of branched macromolecules due to intermolecular chain transfer to polymer similarly as in case of methyl methacrylate–acrylate copolymers. However, the effect is far less pronounced. 相似文献
29.
核壳型氟硅改性丙烯酸酯乳液的合成与膜性能 总被引:1,自引:0,他引:1
采用核壳乳液聚合法合成了氟硅改性丙烯酸酯核壳乳液并对其膜性能进行了系统研究。通过交联基团改性、硅改性、氟改性等手段,合成了核直径约100 nm~150 nm、壳厚度约40 nm~60 nm的粒子大小较均匀的核壳乳液。结果表明,使用5%(质量分数)乙二醇丁醚作为乳液的成膜剂可以改善成膜附着力;通过γ-甲基丙烯酰氧基丙基三... 相似文献
30.
采用阴离子开环乳液聚合法制备了聚硅氧烷共聚乳液,研究了反应条件对共聚动力学及乳胶粒径的影响。结果表明,初始恒速阶段的表观动力学方程为Rp=k[E]0.18[KOH]0.59[M]0.75,表观活化能为52.77 kJ/mol。乳胶粒径随反应温度升高而变小,粒径分布在80℃出现最小值。随[KOH]的增大,乳胶粒径变大,粒径分布变宽。复合乳化剂质量浓度[E]在不同范围内对乳胶粒径及其分布的影响不同,当[E]<0.0572 g/mL时,随[E]增大,乳胶粒径变小,粒径分布变窄;当[E]>0.0572 g/mL时,乳胶粒径反而变大。 相似文献