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81.
Shigenori Kashimura Yoshiyuki Tane Yoshihiro Murai Tomohiro Nakai Ryuich Hirose 《Tetrahedron letters》2008,49(2):269-271
Reduction of dichlorosilanes with Mg metal in the presence of Lewis acid and LiCl was found to be the highly practical method for the synthesis of polysilanes. 相似文献
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84.
Yuki Hirose Kaori Hashiya Dr. Toshikazu Bando Prof. Dr. Hiroshi Sugiyama 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(8):2782-2788
Hairpin pyrrole-imidazole polyamides (hPIPs) and their chlorambucil (Chb) conjugates (hPIP-Chbs) can alkylate DNA in a sequence-specific manner, and have been studied as anticancer drugs. Here, we conjugated Chb to a cyclic PIP (cPIP), which is known to have a higher binding affinity than the corresponding hPIP, and investigated the DNA alkylation properties of the resulting cPIP-Chb using the optimized capillary electrophoresis method and conventional HPLC product analysis. cPIP-Chb conjugate 3 showed higher alkylation activity at its binding sites than did hPIP-Chb conjugates 1 and 2 . Subsequent HPLC analysis revealed that the alkylation site of conjugate 3 , which was identified by capillary electrophoresis, was reliable and that conjugate 3 alkylates the N3 position of adenine as do hPIP-Chbs. Moreover, conjugate 3 showed higher cytotoxicity against LNCaP prostate cancer cells than did conjugate 1 and cytotoxicity comparable to that of conjugate 2 . These results suggest that cPIP-Chbs could be novel DNA alkylating anticancer drugs. 相似文献
85.
Bailly J. L. Caso C. Chiba Y. Dibon H. Epp B. Ferrando A. Fontanelli F. Ganguli S. N. Gémesy T. Gurtu A. Hamatsu R. Hidas P. Hirose T. Hrubec J. Ivanyshenkov Yu. Kageya T. Khalatyan N. Kistenev E. Kita I. Kitamura S. Kubik V. MacNaughton J. Malhotra P. K. Matsumoto S. Mittra I. S. Montanet L. Neuhofer G. Pinter G. Porth P. Raghavan R. Rodrigo T. Singh J. Squarcia S. Takahashi K. Tanaka R. Tikhonova L. A. Trevisan U. Yamagata T. Zholobov G. Zotkin S. A. 《Zeitschrift fur Physik C Particles and Fields》1989,43(3):341-348
Zeitschrift für Physik C Particles and Fields - Correlations among identically charged pions were measured for pions produced inp p collisions at 360 GeV/c using the EHS spectrometer. The... 相似文献
86.
Yoshinori Kamiya Keishin Mizoguchi Yasutoshi Naito Takuji Hirose 《Journal of Polymer Science.Polymer Physics》1986,24(3):535-547
High-pressure sorption (up to 50 atm) for CO2, N2, and Ar in poly(vinyl benzoate) (PVB) was studied at temperatures from 25 to 70°C by a gravimetric method utilizing an electromicrobalance. The results are described by Henry's law above the glass transition temperature Tg for all gases. The dual-mode sorption model, Henry's law plus a Langmuir isotherm, applies to the sorption isotherms of N2 and Ar in the glassy state, and the dual-mode parameters are given. For CO2, a new type of sorption isotherm is observed below Tg. The isotherm is concave to the pressure axis in the low-pressure region and turns into a straight line with increasing CO2 pressure which can be extrapolated back to the coordinate origin. The linear part of the isotherm is characteristic of the rubbery state, while the nonlinear part stems from glassystate behavior. The “glass transition solubility” of CO2, at which PVB film changes from the glassy to the rubbery state, decrease as the temperature increases. The disappearance of microvoids, that is, the decrease of the Langmuir capacity, may be due to a large plasticizing effect of sorbed CO2. The difference between the N2 and Ar isotherms and the CO2 isotherm is discussed from this standpoint. 相似文献
87.
A series of novel optically active 1,3‐aminoalcohols based on cis‐(1R,2S)‐2‐benzamidocyclohexanecarboxylic acid and trans‐(1R,2R)‐2‐benzamidocyclohexanecarboxylic acid were synthesized and used in the asymmetric diethylzinc addition to aromatic aldehydes. Not only the enantioselectivity but also the stereochemistry of the product were controlled by the N‐substituents and the substituents on the vicinity carbon to hydroxyl group of the cis‐derivatives. 相似文献
88.
Kenshu Fujiwara Yuta Hirose Hidetoshi Kawai Takanori Suzuki 《Tetrahedron letters》2010,51(32):4263-4546
Armatol F, isolated from the red alga Chondria armata as a polyether triterpene, has a solitary oxepane (A-ring) and a fused tricyclic ether moiety (BCD-ring). The A-ring features a rare cis-relationship between the hydroxy group at the quaternary carbon C6 and the carbon chain at C7. As part of our program toward the total synthesis of armatol F, a new stereoselective method for the construction of the C6 and C7 stereocenters has been developed based on chirality-transferring Ireland-Claisen rearrangement. The A-ring skeleton has also been synthesized from the rearrangement product by a process including ring-closing olefin metathesis. 相似文献
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90.
The path-integral renormalization group and direct energy minimization method of practical first-principles electronic structure calculations for multi-body systems within the framework of the real-space finite-difference scheme are introduced. These two methods can handle higher dimensional systems with consideration of the correlation effect. Furthermore, they can be easily extended to the multicomponent quantum systems which contain more than two kinds of quantum particles. The key to the present methods is employing linear combinations of nonorthogonal Slater determinants (SDs) as multi-body wavefunctions. As one of the noticeable results, the same accuracy as the variational Monte Carlo method is achieved with a few SDs. This enables us to study the entire ground state consisting of electrons and nuclei without the need to use the Born-Oppenheimer approximation. Recent activities on methodological developments aiming towards practical calculations such as the implementation of auxiliary field for Coulombic interaction, the treatment of the kinetic operator in imaginary-time evolutions, the time-saving double-grid technique for bare-Coulomb atomic potentials and the optimization scheme for minimizing the total-energy functional are also introduced. As test examples, the total energy of the hydrogen molecule, the atomic configuration of the methylene and the electronic structures of two-dimensional quantum dots are calculated, and the accuracy, availability and possibility of the present methods are demonstrated. 相似文献