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121.
Using an analogy to the classical Stefan problem, we construct evolution equations for the fluid pore pressure on both sides of a propagating stress-induced damage front. Closed form expressions are derived for the position of the damage front as a function of time for the cases of thermally-induced damage as well as damage induced by over-pressure. We derive expressions for the flow rate during constant pressure fluid injection from the surface corresponding to a spherically shaped subsurface damage front. Finally, our model results suggest an interpretation of field data obtained during constant pressure fluid injection over the course of 16 days at an injection site near Desert Peak, NV. 相似文献
122.
Kumar Rangaraju Satish Kim Hyorim Mergu Naveen Son Young-A 《Research on Chemical Intermediates》2020,46(1):313-328
Research on Chemical Intermediates - We synthesized a novel dihydroxotin(IV) porphyrin complex with full structural confirmation. The tin complex further converted to TiO2 composite... 相似文献
123.
124.
Karrothu Srihari Babu Mallepalli Srinivasa Reddy Amirisetty Ravindranath Tagore Gade Srinivas Reddy Sony Sebastian Mudunuru Satish Varma 《合成通讯》2013,43(2):291-298
This document describes a simple and robust process for the synthesis of olmesartan medoxomil. This tailored process allows us to synthesize olmesartan medoxomil on a large scale with 50% overall yield. Also, our process has excellent control of the impurity profile in all the stages. 相似文献
125.
K. C. Rajanna M. Venkateswarlu M. Satish Kumar U. Umesh Kumar G. Venkateshwarlu P. K. Saiprakash 《国际化学动力学杂志》2013,45(2):69-80
Vilsmeier–Haack (VH) benzoylation reactions with benzaldehydes and acetophenones in acetonitrile medium obeyed second‐order reaction kinetics. Under kinetic conditions, the reactions afforded benzoyl derivatives irrespective of the nature of oxychloride (POCl3 or SOCl2) used for the preparation of VH reagent along with benzamide. The present finding is advantageous to understand the nature of reactive species as well as the mechanism of benzoylation. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 45: 69–80, 2013 相似文献
126.
Bon-Sung Koo Myung-Hyun Jang Haechul Park Satish Kalme Hey-Yeon Park Jin-Wook Han Yun-Soo Yeo Sang-Hong Yoon Soo-Jin Kim Chang-Muk Lee Moon-Young Yoon 《Applied biochemistry and biotechnology》2010,160(1):122-128
There are several conditions which might modulate polymerization to produce polymers having normal lattice structure. In the absence of 1 mM MgCl2 the assembly was reduced by 36% in Capsicum annuum tubulin (CAnm tubulin). There was no significant difference in the final assembly formation in the presence of 5% to 10% glycerol. However, nucleation rate was slow and apparent study state was achieved lately in the presence of 10% glycerol. Taxol at 100 μM concentration increased 23% tubulin assembly. One millimolar CaCl2, ≥1% dimethyl sulfoxide (DMSO) and physiologically low temperature reduced CAnm tubulin assembly. A value of 0.089 mg/ml was obtained as critical concentration for polymerization. Benomyl significantly reduced the number of cysteine residues accessible to 5,5’-dithiobis-(2-nitrobenzoic acid); there were 4.77?±?0.21 and 3.49?±?0.35 residues accessible per tubulin dimer in the presence of 50 and 100 μM benomyl respectively. 相似文献
127.
Prabhu Suma Mutalik Srinivas Rai Sharada Udupa Nayanabhirama Rao Bola Sadashiva Satish 《Journal of nanoparticle research》2015,17(10):1-22
Journal of Nanoparticle Research - Superparamagnetic iron oxide nanoparticles (SPIONs) are evolving as a mainstay across various applications in the field of Science and Technology. SPIONs have... 相似文献
128.
An efficient synthesis of polyhydroquinolines is achieved via a four-component reaction of aldehydes, dimedone, active methylene compounds, and ammonium acetate in one-pot under solvent-free conditions at room temperature on grinding. The present method does not involve any hazardous organic solvent or catalyst. The key advantages are the short reaction time, high yields, simple workup, and purification of products by non-chromatographic methods, i.e., by simple recrystallization from ethanol. 相似文献
129.
Satish Mishra Rosa M. Badani Prado Song Zhang Thomas E. Lacy Xiaodan Gu Santanu Kundu 《Journal of Polymer Science.Polymer Physics》2019,57(15):1014-1026
Mechanical properties including the failure behavior of physically assembled gels or physical gels are governed by their network structure. To investigate such behavior, we consider a physical gel system consisting of poly(styrene)‐poly(isoprene)‐poly(styrene)[PS‐PI‐PS] in mineral oil. In these gels, the endblock (PS) molecular weights are not significantly different, whereas, the midblock (PI) molecular weight has been varied such that we can access gels with and without midblock entanglement. Small angle X‐ray scattering data reveals that the gels are composed of collapsed PS aggregates connected by PI chains. The gelation temperature has been found to be a function of the endblock concentration. Tensile tests display stretch‐rate dependent modulus at high strain for the gels with midblock entanglement. Creep failure behavior has also been found to be influenced by the entanglement. Fracture experiments with predefined cracks show that the energy release rate scales linearly with the crack‐tip velocity for all gels considered here. In addition, increase of midblock chain length resulted in higher viscous dissipation leading to a higher energy release rate. The results provide an insight into how midblock entanglement can possibly affect the mechanical properties of physically assembled triblock copolymer gels in a midblock selective solvent. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 1014–1026 相似文献
130.
Ravi Kiran Kaja K. V. Surendranath P. Radhakrishnanand J. Satish P. V. V. Satyanarayana 《Chromatographia》2010,72(5-6):441-446
A novel, sensitive, stability indicating RP-LC method has been developed for the quantitative determination of deferasirox, its related impurities in both bulk drugs and pharmaceutical dosage forms. Efficient chromatographic separation was achieved on a C18 stationary phase with simple mobile phase combination delivered in an isocratic mode and quantitation was by ultraviolet detection at 245 nm. The mobile phase consisted of buffer, acetonitrile and methanol (50:45:5, v/v) delivered at a flow rate of 1.0 mL min?1. Buffer consisted of 10 mM potassium dihydrogen orthophosphate monohydrate, pH adjusted to 3.0 by using orthophosphoric acid. In the developed LC method the resolution (R s ) between deferasirox and its four potential impurities was found to be greater than 2.0. Regression analysis showed an r value (correlation coefficient) greater than 0.999 for deferasirox and its four impurities. This method was capable to detect all four impurities of deferasirox at a level of 0.002% with respect to test concentration of 0.5 mg mL?1 for a 10 μL injection volume. The inter- and intra-day precision values for all four impurities and for deferasirox was found to be within 2.0% RSD. The method showed good and consistent recoveries for deferasirox in bulk drugs (98.3–101.1%), pharmaceutical dosage forms (100.2–103.1%) and for its all the four impurities (99.7–102.1%). The test solution was found to be stable in methanol for 48 h. The drug was subjected to stress conditions of hydrolysis, oxidation, photolysis and thermal degradation. Considerable degradation was found to occur in acid stress hydrolysis. The stress samples were assayed against a qualified reference standard and the mass balance was found close to 99.95%. The developed RP-LC method was validated with respect to linearity, accuracy, precision and robustness. 相似文献