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31.
Pezhman Kazemi Mohammad Peydayesh Alireza Bandegi Toraj Mohammadi Omid Bakhtiari 《Chemical Papers》2013,67(7):722-729
An experimental study on the pertraction of methylene blue (MB) through a supported liquid membrane (SLM) using a mixture of mono-(2-etylhexyl) ester of phosphoric acid (M2EHPA) and bis-(2-etylhexyl) ester of phosphoric acid (D2EHPA) and sesame oil as the liquid membrane (LM) was performed. Parameters affecting the pertraction of MB such as initial MB concentration, carrier concentration, feed phase pH, and stripping phase concentration were analyzed. Optimal experimental conditions for MB pertraction (permeability of 5.63 × 10?6) were obtained after a 7 h separation with the MB concentration in the feed phase of 80 mg L?1, D2EHPA/M2EHPA concentration in membrane phase of 40 vol. %, feed pH of 6, and acetic acid concentration in the stripping phase of 0.4 mol L?1. Kinetics of transport and stability of the SLM system were also studied and the mass transfer coefficient for this system was evaluated. Scanning electron microscopy (SEM) was used to morphologically characterize the membrane surface. 相似文献
32.
Mohammad Hassan Baig Tanuj Sharma Irfan Ahmad Mohammed Abohashrh Mohammad Mahtab Alam Jae-June Dong 《Molecules (Basel, Switzerland)》2021,26(6)
The COVID-19 outbreak continues to spread worldwide at a rapid rate. Currently, the absence of any effective antiviral treatment is the major concern for the global population. The reports of the occurrence of various point mutations within the important therapeutic target protein of SARS-CoV-2 has elevated the problem. The SARS-CoV-2 main protease (Mpro) is a major therapeutic target for new antiviral designs. In this study, the efficacy of PF-00835231 was investigated (a Mpro inhibitor under clinical trials) against the Mpro and their reported mutants. Various in silico approaches were used to investigate and compare the efficacy of PF-00835231 and five drugs previously documented to inhibit the Mpro. Our study shows that PF-00835231 is not only effective against the wild type but demonstrates a high affinity against the studied mutants as well. 相似文献
33.
Structural Chemistry - Applying a theoretical approach that combines an efficient and fast global optimization based on genetic algorithms (GA) to search in structure space and the parameterized... 相似文献
34.
We consider a model for magnetic memory that consists of strongly coupled dipolar or antiferromagnetic (AF) pairs with inequivalent perpendicular anisotropy K1 and K2. For appropriate parameter values, determined in this work, they have two inequivalent storage states with zero net magnetic moment. Both analytical and numerical calculations are performed, in some cases yielding different results because of relaxation effects (i.e., a dependence on the damping parameter α). Hysteresis loops for a wide variety of parameter values are obtained, both for the AF case and the dipole case. An Appendix gives analytic results for slightly non-collinear spins in an applied field, which were used to test the numerical results. 相似文献
35.
Sanaei-Rad Saleheh Saeidiroshan Hakimeh Mirhosseini-Eshkevari Boshra Ghasemzadeh Mohammad Ali 《Research on Chemical Intermediates》2021,47(5):2143-2159
Research on Chemical Intermediates - Regarding the significance of medicinal and pharmacological sciences, we explored one-pot multicomponent reaction of aromatic aldehydes, aryl amines,... 相似文献
36.
JPC – Journal of Planar Chromatography – Modern TLC - A mobile phase system comprising of ethyl acetate and propionic acid in 1:1 (v/v) ratio was identified as the most suitable green... 相似文献
37.
Dr. Xinghai Ning Dr. Wonewoo Seo Dr. Seungjun Lee Dr. Kiyoko Takemiya Dr. Mohammad Rafi Dr. Xuli Feng Dr. Daiana Weiss Dr. Xiaojian Wang Larry Williams Vernon M. Camp Malveaux Eugene Prof. W. Robert Taylor Prof. Mark Goodman Prof. Niren Murthy 《Angewandte Chemie (International ed. in English)》2014,53(51):14096-14101
A positron emission tomography (PET) tracer composed of 18F‐labeled maltohexaose (MH18F) can image bacteria in vivo with a sensitivity and specificity that are orders of magnitude higher than those of fluorodeoxyglucose (18FDG). MH18F can detect early‐stage infections composed of as few as 105 E. coli colony‐forming units (CFUs), and can identify drug resistance in bacteria in vivo. MH18F has the potential to improve the diagnosis of bacterial infections given its unique combination of high specificity and sensitivity for bacteria. 相似文献
38.
Oxidative desulfurization (ODS) is the promising new method for super deep desulfurization of fuel oil. The oxidative desulfurization performance of the metal-N4-chelates metallophthalocyanines (MPcs) is related to the chemical properties of conjugate structures and the central metal ions. Herein, a biomimetic catalytic system composed of metallophthalocyanines (MPcR4, M = Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II); R = -H, -COOH, -NO2, -NH2) and molecular O2 was performed to study the influence of MN4-type coordination structure in metallophthalocyanines for the degradation of dibenzothiophene (DBT) in model oil containing n-octane. The results reveal that the conjugate structures and the center metal ions of metallophthalocyanines played key roles in oxidative desulfurization performance. The inductive effect of different R substituents strongly affected the electron cloud distribution of the conjugate structures and the catalytic performance. Moreover, the catalytic activity of MPcs, which is related to the d electronic configuration and ligand-field effects, does not sequentially increase with the increase in the d electron number of central metal ions. 相似文献
39.
Jeon Min-Kyung Kim Seunghee Hosseini Zadeh Amin Kwon Tae-Hyuk 《Transport in Porous Media》2020,133(2):207-227
Transport in Porous Media - We investigate viscous fluid flows and concurrent fluid-driven deformations in porous media. The hydro-mechanically (H-M) coupled pore-network model (PNM) is developed,... 相似文献
40.
The present study aims to modify a recently suggested implicit approach consisted of the approximate Euler method and closed-form exponential mapping (herein referred to as the Liu scheme) for the dynamic analysis of structures. Such modification has been developed based upon nonstandard rules. The equation of motion is formulated in the augmented dynamic space to apply the exponential mapping as a group preserving scheme. The formulation of the proposed method involves the hyperbolic sine and cosine functions. The method is therefore prone to divergence due to the behavior of the hyperbolic functions in structures with a high ratio of stiffness to mass. In the present study, to consider the properties of the structural equation into the formulation of the time step size and thereby avoid the divergence, a parameter, known as stability parameter, is thus derived from the exact solution of the equation of motion based on nonstandard rules. Embedding this parameter into the proposed method improves its stability. Afterward, for evaluating the performance of the proposed method, it is applied to several structures with different loading patterns while implemented in programing environment of the Matlab software. The results are compared to those of several commonly used numerical methods in structural applications. It is found that the proposed method has acceptable convergence and accuracy, and low time consumption compared to several commonly used methods. Furthermore, its stability is guaranteed by embedding the stability parameter into the proposed method. 相似文献