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901.
Sn-doped Ga1.4In0.6O3 films have been prepared on α-Al2O3 (0 0 0 1) substrates by the metalorganic chemical vapor deposition (MOCVD) method. The Sn-doping was varied from 0% to 7% (atomic ratio). Polycrystalline films with resistivity of 4.9 × 10−3Ω cm, carrier concentration of 5.9 × 1019 cm−3 and Hall mobility of 21.4 cm2 v−1 s−1 was obtained at 5 at.% of Sn concentration. The average transmittance for the Sn-doped Ga1.4In0.6O3 films in the visible range was over 90%. The bandgap of the films varies from 3.85 to 4.21 eV. 相似文献
902.
903.
Ciprian Foias Luan Hoang Basil Nicolaenko 《Communications in Mathematical Physics》2009,290(2):679-717
We study the asymptotic behavior of the statistical solutions to the Navier–Stokes equations using the normalization map [9].
It is then applied to the study of mean energy, mean dissipation rate of energy, and mean helicity of the spatial periodic
flows driven by potential body forces. The statistical distribution of the asymptotic Beltrami flows are also investigated.
We connect our mathematical analysis with the empirical theory of decaying turbulence. With appropriate mathematically defined
ensemble averages, the Kolmogorov universal features are shown to be transient in time. We provide an estimate for the time
interval in which those features may still be present.
Our collaborator and friend Basil Nicolaenko passed away in September of 2007, after this work was completed. Honoring his contribution and friendship, we dedicate this article to him.相似文献
904.
905.
Wang W. J. Luan S. R. Chen Y. R. Cal L. Z. Jia Y. Q. Ruan S. K. Duan J. F. 《Journal of Thermal Analysis and Calorimetry》2001,63(3):823-830
New complexes of the non-natural amino acid (p-iodo-phenylalanine) with divalent cobalt and nickel ions have been synthesized. The composition of the complexes is [M(IC6H4CH2CHNH2COO)2]×2.5H2O (M=Co, Ni) and the crystal structure belongs to orthorhombic system. Infrared spectra indicate the nature of bonding in the
complex. The first stage in the thermal decomposition process of the complex shows the presence of crystal water. The thermal
decomposition process of cobalt complex differs from that of nickel. The intermediate and final residues in the thermal decomposition
process have been analyzed to check the pyrolysis reactions. Thermal analysis indicates that the iodine atom of the ligand
may coordinate to the metal ion in the lattice.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
906.
Tainara Boareto Capelari Arnaldo César Pereira Leandro Luan Gonçalves de Oliveira 《Analytical letters》2019,52(9):1462-1476
A simple, low-cost and sensitive electroanalytical method was developed for the simultaneous determination of p-nitrophenol and o-nitrophenol isomers in water samples at a glassy carbon electrode (CGE) in the presence of cationic surfactant. The electrochemical behavior of p-nitrophenol and o-nitrophenol was studied by cyclic voltammetry (CV) in 0.1?mol L?1 acetate/acetic acid buffer (pH 3.70) in the presence and absence of cetylpyridinium bromide. The resolution of overlapped cathodic peaks potentials (Epc) of isomers was successfully improved in the presence of 100.0?µmol L?1 cetylpyridinium bromide, thus making this approach ideal for the simultaneous determination of isomers. Under the optimized conditions in 0.05?mol L?1 HEPES buffer at pH 7.0 using differential pulse voltammetry (DPV) at a scan rate of 45?mV s?1, pulse amplitude of 220?mV and modulation time of 10?ms, limits of detection 0.59?µmol L?1 for p-nitrophenol and 1.14?µmol L?1 for o-nitrophenol were obtained with linear ranges from 2.0 to 60.0?µmol L?1 and 3.0 to 60.0?µmol L?1, respectively. The intraday precision was assessed as relative standard deviation (%) for 20.0 and 40.0?µmol L?1 concentrations were 4.30% and 2.41% for p-nitrophenol and 4.87% and 2.20% for o-nitrophenol, respectively. The developed method was applied for the determination of the isomers in lake water samples. The accuracy was attested by comparison with high-performance liquid chromatography with diode array detection (HPLC-DAD) as a reference analytical technique. Recovery values ranging from 90.3% to 111.8% also attested to the accuracy of method for analysis of real samples. 相似文献
907.
Qi Zhang Jingyi Luan Liang Fu Shengan Wu Yougen Tang Xiaobo Ji Haiyan Wang 《Angewandte Chemie (International ed. in English)》2019,58(44):15555-15555
908.
Qiaoqin Li Xiaoqin Wang Nana Yang Fan He Yufei Yang Bohua Wu Jia Chu Anning Zhou Shanxin Xiong 《无机化学与普通化学杂志》2019,645(16):1022-1030
Hydrangea‐like NiCo‐based bimetal‐organic frameworks (NiCo‐MOF) are synthesized in DMF‐EtOH solution via a solvothermal method, using 4,4′‐biphenyldicarboxylic acid as a ligand. NiCo‐MOF having a highest capacity of 1056.6 F · g–1 at 0.5 A · g–1 and 457.7 F · g–1 even at 10 A · g–1 is achieved at a Ni/Co/BPDC molar ratio of 1:1:1, a temperature of 170 °C and a reaction time of 12 hours. It exhibits secondary 3D microsphere structures assembled by primary 2D nanosheet structures, good crystalline structure and good thermal stability below 350 °C in air. All the electrochemical data show that NiCo‐MOF has the pros and cons as supercapacitor electrode materials in aqueous electrolytes. On the one hand, NiCo‐MOF has a high capacity even at a high current density, low internal resistance, charge‐transfer resistance and ion diffusion impendence, owing to the ordered coordination structure, 2D nanosheet structure and 3D assembled microsphere structure of NiCo‐MOF. On the other hand, the cycling stability and rate capability are not ideal enough due to the hydrolysis of coordination bonds in aqueous electrolytes, especially, in alkaline solution. The good dispersion and high electrochemical activity of metal ions bring a high capacity for NiCo‐MOF, but they result in the poor stability of NiCo‐MOF. In the future work, finding a suitable organic electrolyte is an effective way to enhance the cycling stability of NiCo‐MOF as well as deriving more stable skeleton materials from NiCo‐MOF. 相似文献
909.
Qi Zhang Jingyi Luan Liang Fu Shengan Wu Yougen Tang Xiaobo Ji Haiyan Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(44):15988-15994
Rechargeable aqueous zinc‐ion batteries have been considered as a promising candidate for next‐generation batteries. However, the formation of zinc dendrites are the most severe problems limiting their practical applications. To develop stable zinc metal anodes, a synergistic method is presented that combines the Cu‐Zn solid solution interface on a copper mesh skeleton with good zinc affinity and a polyacrylamide electrolyte additive to modify the zinc anode, which can greatly reduce the overpotential of the zinc nucleation and increase the stability of zinc deposition. The as‐prepared zinc anodes show a dendrite‐free plating/stripping behavior over a wide range of current densities. The symmetric cell using this dendrite‐free anode can be cycled for more than 280 h with a very low voltage hysteresis (93.1 mV) at a discharge depth of 80 %. The high capacity retention and low polarization are also realized in Zn/MnO2 full cells. 相似文献
910.
Takeshi Yoshikawa Nana Komoto Yoshifumi Nishimura Hiromi Nakai 《Journal of computational chemistry》2019,40(31):2778-2786
The present study implemented the divide-and-conquer time-dependent density-functional tight-binding (DC-TDDFTB) code on a graphical processing unit (GPU). The DC method, which is a linear-scaling scheme, divides a total system into several fragments. By separately solving local equations in individual fragments, the DC method could reduce slow central processing unit (CPU)-GPU memory access, as well as computational cost, and avoid shortfalls of GPU memory. Numerical applications confirmed that the present code on GPU significantly accelerated the TDDFTB calculations, while maintaining accuracy. Furthermore, the DC-TDDFTB simulation of 2-acetylindan-1,3-dione displays excited-state intramolecular proton transfer and provides reasonable absorption and fluorescence energies with the corresponding experimental values. © 2019 Wiley Periodicals, Inc. 相似文献