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581.
Tahira Sultana Madiha Ahmed Nosheen Akhtar Mohammad K. Okla Abdulrahman Al-Hashimi Wahidah H. Al-Qahtani Hamada Abdelgawad Ihsan-ul-Haq 《Molecules (Basel, Switzerland)》2022,27(2)
The present study was designed to evaluate polarity-dependent extraction efficiency and pharmacological profiling of Polygonum glabrum Willd. Crude extracts of leaves, roots, stems, and seeds, prepared from solvents of varying polarities, were subjected to phytochemical, antioxidant, antibacterial, antifungal, antidiabetic, and cytotoxicity assays. Maximum extraction yield (20.0% w/w) was observed in the case of an acetone:methanol (AC:M) root extract. Distilled water:methanol (W:M) leaves extract showed maximum phenolic contents. Maximum flavonoid content and free radical scavenging potential were found in methanolic (M) seed extract. HPLC-DAD quantification displayed the manifestation of substantial quantities of quercetin, rutin, gallic acid, quercetin, catechin, and kaempferol in various extracts. The highest ascorbic acid equivalent total antioxidant capacity and reducing power potential was found in distilled water roots and W:M leaf extracts, respectively. Chloroform (C) seeds extract produced a maximum zone of inhibition against Salmonella typhimurium. Promising protein kinase inhibition and antifungal activity against Mucor sp. were demonstrated by C leaf extract. AC:M leaves extract exhibited significant cytotoxic capability against brine shrimp larvae and α-amylase inhibition. Present results suggest that the nature of pharmacological responses depends upon the polarity of extraction solvents and parts of the plant used. P. glabrum can be considered as a potential candidate for the isolation of bioactive compounds with profound therapeutic importance. 相似文献
582.
Numerical analysis and experimental results of output performance for Nd-doped double-clad fiber lasers 总被引:10,自引:0,他引:10
Nam Seong Kim Toshihiro Hamada Mahendra Prabhu Cheng Li Jie Song Ken-ichi Ueda Anping Liu Hong Jin Kong 《Optics Communications》2000,180(4-6):329-337
Numerical analysis is investigated for the high-power double-clad fiber lasers and experimental results using different microscope objectives for focusing into a Nd-doped rectangular double-clad fiber also performed. The numerical analysis includes dependence of output power on output mirror reflectivity, absorbed pump power, loss, and fiber length and pump power distribution for the cases of one-end and two-end pumps with 20 dB/km loss. Calculated conversion efficiencies are 76.36%, 69.73%, and 63.84% for lossless, two-end pump, and one-end pump fiber lasers, respectively. Slope efficiencies from absorbed pump power/output powers measured using microscope objectives are 16.8%/182 mW, 53.8%/351 mW, 24.9%/1240 mW, and 13.9%/649 mW for magnifications of 5×, 10×, 20×, and 40×, respectively. 相似文献
583.
Shinya Harusawa Ryuji Yoneda Takushi Kurihara Yasumasa Hamada Takayuki Shioiri 《Tetrahedron letters》1984,25(4):427-428
Reaction of aromatic ketones with diethyl phosphorocyanidate in the presence of lithium cyanide gave cyanophosphates, which were converted into α,β-unsaturated nitriles by treatment with boron trifluoride etherate in high yields. 相似文献
584.
The reconstruction and the relaxation of the (001) surface of Mo and W are studied by using the tight-binding d band and the Born-Mayer repulsive potential. The d band parameters are set to reproduce band energies of ab initio band calculations at high symmetry points in the Brillouin zone and the parameters in the Born-Mayer potential are chosen to obtain the correct equilibrium lattice constant and the bulk modulus of the bulk crystal. First, we give a detailed discussion on the mechanism of the surface relaxation, and then show that the (001) surfaces of Mo and W are unstable to the c(2 × 2) mode but stable with regard to the (2 × 1) mode. By calculating the energy change up to the fourth order of atomic displacement, we determine the stable surface atomic structure which is in fair agreement with experiments. 相似文献
585.
Wave trajectories of the ordinary mode as well as the extraordinary one injected obliquely into a magnetic field in high density toroidal plasmas, are studied theoretically. Both waves are finally converted into the electron Bernstein mode and cyclotron damped. 相似文献
586.
Translational diffusion and internal motion have been observed by dynamic light scattering of optically labeled single chains of polystyrene (PS) in a semidilute solution of poly(methyl methacrylate) and benzene for the case in which the dimension Rg of the PS chain is comparable to the correlation length of the matrix solution. The molecular weight Mw dependence of the hydrodynamic radius Rh is expressed as Rh ~ M, while Rh ~ M in pure benzene. The average linewidth Γ for internal motions (KRg > 1) appears to depend on the magnitude K of the scattering vector approximately as Γ ∝ K4 at higher KRg ( > 1), in contrast with the fact that Γ ∝ K3 approximately for KRg > 1 in pure benzene. The scaling law for the K dependence of Γ does not hold in low-molecular-weight PS owing to the K dependence of Γ /K2 for KRg < 1. 相似文献
587.
588.
Koji Ishida Tomoshige Morita Takeshi Hamada Yoichi Takeda Shuji Ninomiya 《Fresenius' Journal of Analytical Chemistry》1988,332(7):791-794
Summary The separation of Rh(III) and Ir(IV) in amounts of 20–5300 and 20–7700 g, respectively, and in ratios of RhIr=1100 to 1001 was achieved without cross-contamination by use of a 3 g ECTEOLA-cellulose column. Rh was first eluted with 40 ml of a 3 mol/l HCl-1% (w/v) NaClO3 solution. Ir(IV) was desorbed with 60 ml of a 6 mol/l HCl-0.1% (w/v) NaClO3 solution. Quantitative recoveries were obtained for each metal. The present method provides much better resolution than the other existing anion-exchange methods and can effectively be applied to the separations and recoveries of Rh and Ir(III or IV) present in a more extensive range of amounts and ratios.
Anionenaustausch-Trennung von Rhodium und Iridium mit Hilfe einer ECTEOLA-Cellulose-Säule相似文献
589.
Saburo Yamaguchi Hisao Hayashi Fumiyuki Hamada Akio Nakajima 《Journal of Polymer Science.Polymer Physics》1984,22(9):1551-1559
Scattering functions for amylose chains have been calculated as a statistical mechanical average over eligible configurations based on the rotational isomeric state approximation. Main emphasis has been placed on an intermediate-angle range (0.1 < h = (4π/γ)sinθ < 1.0 Å?1) where the scattering function is sensitive to local chain configurations. In order to avoid overestimation of the regularity of chain configurations, the rotational isomeric states for each glycosidic bond have been defined by a set of discrete torsion angles at intervals of 5°. Pair correlation functions for atoms separated by sequences shorter than 31 glucose units are evaluated by the Monte Carlo method, while the interference for longer sequences is calculated by a series expansion in the even moments of the chain. All carbons and all skeletal oxygens are treated as point scatterers in order to incorporate all the interferences between atoms in unit pairs in the calculations. The calculated scattering function shows appreciable oscillation at intermediate angles, reflecting the characteristic helical tendency of the configurations. The Debye function is found to be inadequate in the intermediate-angle region owing to the non-Gaussian character of the distribution function and to breakdown of the assumption that the mean-square distance between a pair of atoms is proportional to the number of bonds between them, because of the bulkiness of the glucose unit. 相似文献
590.
Patellamides B and C, cytotoxic lipophilic cyclic peptides from a marine tunicate, with proposed structures have been synthesized by the use of diphenyl phosphorazidate(DPPA) and diethyl phosphorocyanidate(DEPC). Their physicochemical properties lead to reassign the structures of patellamides B and C on the bonding order. 相似文献