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排序方式: 共有247条查询结果,搜索用时 15 毫秒
241.
A quantized symplectic oscillator algebra of rank 1 is a PBW deformation of the smash product of the quantum plane with . We study its representation theory, and in particular, its category . 相似文献
242.
We obtain exact solutions for the motion of a classical anharmonic oscillator in the potential Bx
2–|A|x
4+Cx
6, and discuss the energy dependence of the frequencies of oscillation. 相似文献
243.
Parab K Venkatasubbaiah K Jäkle F 《Journal of the American Chemical Society》2006,128(39):12879-12885
A new class of highly fluorescent triarylborane polymers has been prepared from trimethylsilyl-substituted polystyrene via a modular approach that involves selective polymer modification reactions with organometallic reagents. The photophysical properties, environmental stability, and the Lewis acidity of the boron sites have been tailored through modifications in the substitution pattern on boron. The photophysical properties are indicative of electronic communication between the chromophores attached to polystyrene, which has been exploited for the efficient probing of fluoride and cyanide in the micromolar concentration range. 相似文献
244.
Tejshri R. Deshmukh Smita P. Khare Vagolu S. Krishna Dharmarajan Sriram Jaiprakash N. Sangshetti Omprakash Bhusnure Vijay M. Khedkar Bapurao B. Shingate 《Journal of heterocyclic chemistry》2019,56(8):2144-2162
A quest for more potent new antitubercular agents has prompted to design and synthesize aryloxy‐linked dimeric 1,2,3‐triazoles ( 4a – j ), from azides ( 2a‐e ) and bis(prop‐2‐yn‐1‐yloxy)benzene ( 3a – b ) on 1,3‐dipolar cycloaddition reaction via copper (I)‐catalyzed click chemistry approach with good to better yields. The titled compounds ( 4a – j ) were designed using molecular hybridization approach by assembling various bioactive pharmacophoric fragments in a single molecular framework. All the synthesized compounds have been screened for their in vitro antitubercular, antifungal, and antioxidant activities against their respective strains. Among them, 4h and 4i show the highest antifungal activity, whereas compounds 4h , 4i , and 4j have revealed promising antitubercular activity against their respective strains. In addition to this, most of the synthesized compounds were found as potent antifungal and antioxidant agents. A significant network of bonded and non‐bonded interactions stabilized these molecules into the active site of fungal CYP51 that is realized from the obtained well‐placed docking poses and the associated thermodynamic interactions with the enzyme. The synthesized compounds have also been analyzed for absorption, distribution, metabolism, and excretion properties. 相似文献
245.
April L. Fogel Ashwin Ravichandran Sriramvignesh Mani Bishal Upadhyay Rajesh Khare Sarah E. Morgan 《Journal of Polymer Science.Polymer Physics》2019,57(10):584-597
Glycohydrogels containing 2′‐acrylamidoethyl‐β‐d ‐galactopyranoside and varying levels of N,N′ methylene bisacrylamide and 3‐acrylamidopropyltris(trimethylsiloxy)silane were synthesized to determine the effects of crosslinker and amphipathic balance on equilibrium water content (EWC), bound water population, and hydrogen bonding dynamics at the water–polymer interface. Analogous dimethylacrylamide hydrogels were synthesized for comparison with a system containing lower hydrogen bonding propensity. An approach combining experiment (proton nuclear magnetic resonance, thermogravimetric analysis, differential scanning calorimetry, and dynamic vapor sorption analysis) and molecular dynamics simulations was employed to examine the relationship between bulk hydrogel properties, molecular water mobility, and hydrogen bonding characteristics. It was found that copolymer composition (hydrophobic content) and crosslink concentration in high water content glycohydrogels affect EWC, and by extension, structural water population. The organization of water at the polymer interface is greatly impacted by the surrounding environment, where hindered molecular water mobility promotes water–polymer binding and decreases water–water clustering. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 584–597 相似文献
246.
B. P. Chandra Yuvraj Rahangdale P. K. Khare D. P. Bisen Deepti Sharma 《Crystal Research and Technology》1995,30(5):691-701
A quantum mechanical approach is made to the deformation-induced electronic excitation in crystals. The ML intensity is assumed to be related to the transition probability P(m, n) from nth to mth state, and it may be expressed as IML = βP(m, n) where P(m, n) = 4π2/hα2 |σmn (ωmn)|2 ·( n · μ )mn·2. It is shown that the ML excitation can take place only by the time-dependent applied stress. The ML excitation probability is analysed for different waveforms of the applied stress such as constant stress, δ-function, rectangular stress, single sided and double sided exponential stress, unit step function, external sinusoidal signals cos ω0t and sin ω0t, external exponential function, a periodic function and the stress of sequence of equidistant impulses of unit strength separated by a particular time. It is found that when the stress is a δ-function, a rectangular waveform, sinusoidal singals cos ω0t and sin ω0t or a sequence of equidistant impulses of unit strength and separated by a particular time, then there is a considerable probability of electronic excitation by the resonance transfer mechanism between the Fourier transform of the stress waveform and the frequency of the emitting electronic system i.e. (E2 – E1)/h. 相似文献
247.
Yang Qin Guanglou Cheng Kshitij Parab Anand Sundararaman Frieder Jäkle 《Macromolecular Symposia》2003,196(1):337-345
We have developed a highly efficient new method for the introduction of Lewis acidic boron centers into the side chains of organic polymers. Our methodology involves three steps: (i) the controlled polymerization of a functional monomer, (ii) the exchange of the functional group for Lewis acidic boron centers, and (iii) the fine-tuning of the Lewis acidity of the individual centers through substituent exchange reactions with nucleophiles. This approach gives access to a family of new well-defined organoboron polymers including moderately Lewis acidic poly(arylboronates) and the first examples of highly Lewis acidic fluorinated triarylborane polymers. 相似文献