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151.
Various anhydride-terminated isotactic and atactic oligopropenes of number average molecular weights ranging between 1,000 and 10,000 g/mole, prepared by maleinating vinylidene-terminated propene oligomers obtained with isospecific and nonstereospecific metallocene-based Ziegler–Natta catalysts, have been evaluated as blend compatibilizers of polypropylene/polyamide-6 (70 vol%/30 vol%) blends to study the role of blend compatibilizer molecular architecture. When added during processing, as shown by IR spectroscopic analysis, the anhydride-terminated oligopropenes react with the amine-terminated polyamide-6 to yield polypropylene-block-polyamide-6 in situ. Such block copolymers are efficient dispersing agents. While the polyamide dispersion in the polypropylene continuous phase is not affected by blend compatibilizer stereoregularities, both stiffness and yield stress as well as notched Charpy impact strength increase with increasing stereoregularities and molecular weights. With oligopropene molecular weights exceeding 1,150 g/mole, the average size of the dispersed polyamide microphases correlates with the volume fraction of the oligopropene-block-polyamide-6 blend compatibilizer and the dicarboxylic acid anhydride/amine molar ratio. 相似文献
152.
The first cocrystals of polymorphic maleic hydrazide with 3-methyluracil have been studied by X-ray diffraction methods. They crystallize in the orthorhombic system, space group Pmcn, a = 6.440 (1) Å, b = 6.974 (1) Å, c = 22.829 (11) Å, V = 1025.3 (5) Å3, Z = 4. The asymmetric unit contains one molecule of each compound. Planar ribbons of the (1:1) molecular complex are obtained through the formation of O–H···O and O–H···N intermolecular hydrogen bonds, just forming a well-known R2
2(8) supramolecular synthon. Supramolecular assemblies are then formed by weak C–H···O and C–H···N hydrogen bonds through adjacent antiparallel ribbons. 相似文献
153.
Kónya M. Sorrenti M. Ferrari F. Rossi S. Csóka I. Caramella C. Bettinetti G. Erős I. 《Journal of Thermal Analysis and Calorimetry》2003,73(2):623-632
Thermogravimetric and rheological investigations of oil/water (o/w) creams prepared with different types of surface-active
agents (non-ionic, non-ionic POE-free, ionic) were carried out. Thermogravimetry was aimed at the indirect study of the water
bond mechanism in o/w creams and the influence of the composition, type and concentration of the mixed emulsifier on the binding
of water incorporated in the structure (interlamellar, bulk) and on the binding proportions. The microstructural changes during
application were studied with respect to the stability of the lamellar bilayer.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
154.
Photo-reactive bisazide in a polymer matrix containing acryloyl groups on the side chain was investigated as a photoalignment layer for polymerizable liquid crystals (PLC). We found the thin film of bisazide (2,6-bis(4-azidobenzylidene)-4-methyl-1-cyclohexanone) in a polymer matrix, irradiated by linearly polarised ultraviolet light (LPUVL), was able to homogeneously align PLC. The LPUVL irradiation dose changed the orientation direction of the PLC on the thin film of bisazide in the polymer matrix. In addition, the direction of the slow axis for the retardation of the photoalignment layer changed from parallel to perpendicular to the LPUVL electric field with the irradiation dose. From these results, it was suggested that the PLC was likely to be aligned along the slow axis of the retardation of the photoalignment layer. We concluded that the key mechanism that changed the direction of the slow axis in a plane was the photoreaction of azide–acrylate at low irradiation dose and that of bis(benzylidene)cyclohexanone at high irradiation dose. Although the photoalignment as a result of a simple photo cross-linking was previously little known except for photo-dimerisation, we revealed that the photoaddition of azide–acrylate is able to achieve the photoalignment. 相似文献
155.
有机硅改性丙烯酸酯乳液的流变性 总被引:10,自引:0,他引:10
聚合物乳液;流变性能;反应性乳液;有机硅改性丙烯酸酯乳液的流变性 相似文献
156.
Masami Iyo Kosuke Tsutsui Atsushi Kameyama Tadatoimi Nishikubo 《Journal of polymer science. Part A, Polymer chemistry》1999,37(16):3071-3078
Novel polyfunctional (meth)acrylates with a calixarene backbone [calixarene (meth)acrylates] were synthesized in good yields by certain reactions of p-methylcalix[6]arene (1a) or p-tert-butylcalix[6]arene (1b) with (meth)acrylate derivatives such as acryloyl chloride, methacryloyl chloride, (2-methacryloxy)ethyl isocyanate, and glycidyl methacrylate. Polyfunctional acrylate 6a having poly(oxyethylene) spacer chain between 1a and acrylate groups was also synthesized by the reaction of the poly(oxyethylene) modified 1a with acrylic acid. Calixarene acrylate 6a was liquid at room temperature, although the other calixarene (meth)acrylates were solid at room temperature. The initial decomposition temperature (IDT) of the resulting calixarene (meth)acrylates was measured by the thermogravimetric analysis to evaluate the thermal stability, and it was found that some of the IDTs of the calixarene acrylates were over 400°C. This means that calixarene (meth)acrylates have very good thermal stability. The photopolymerization of the resulting some calixarene (meth)acrylates with (2-phenyoxy)ethyl acrylate as a reactive diluent in the presence of photoinitiator proceeded smoothly upon irradiation with UV light. Therefore, polyfunctional (meth)acrylates with a calixarene backbone can be expected to be novel and thermally stable photoreactive acrylate oligomers. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3071–3078, 1999 相似文献
157.
在甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)的无皂乳液聚合体系中,加入少量反应性乳化剂ω-十一烯酸钠(SUA),用粒度分布仪、透射电子显微镜表征了胶粒平均直径、浓度及形态,用离子交换-电导滴定分析了胶粒表面性质。 相似文献
158.
D. Zou S. Ma R. Guan M. Park L. Sun J. J. Aklonis R. Salovey 《Journal of polymer science. Part A, Polymer chemistry》1992,30(1):137-144
Monodisperse polymethacrylate beads of varied size and crosslink density are prepared by emulsion copolymerization of methacrylate and divinyl monomers in the absence of emulsifiers. The sizes of polybutyl and polyethyl methacrylate beads decreased with increasing polymerization temperature, while polymethyl methacrylate beads were largely unchanged in size. The molar mass of polymer in polymethyl metnacrylate beads markedly exceeded that in polystyrene beads. The rate of polymerization increased, and bead size decreased, with increasing initiator concentration or decreasing monomer concentration. The polymethacrylate beads are used as filler particles in polymer composites. 相似文献
159.
160.
利用改进的沸点仪测定了顺酐-癸二酸二丁酯二元体系在413.15, 433.15和453.15 K下的等温气液平衡数据以及纯癸二酸二丁酯和顺酐的饱和蒸气压数据. 通过与文献值对比, 验证了此方法的可靠性. 同时, 将实验数据回归得到了纯癸二酸二丁酯和顺酐的Antoine常数. 利用NRTL方程进行了气液平衡数据的关联推算, 得到了顺酐-癸二酸二丁酯二元体系的NRTL模型参数. 利用UNIFAC基团贡献法对实验数据进行了预测, 其结果与实验值及运用NRTL方程拟合的结果吻合较好. 相似文献