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81.
Hassan Badawi Primo
Loren
ak Kurt W. Hillig II Misako Imachi Robert L. Kuczkowski 《Journal of Molecular Structure》1987,162(3-4):247-254
The microwave spectrum of the normal species of the gauche, gauche isomer of allyl alcohol has been reassigned and rotational and centrifugal distortion constants have been determined. Rotational constants of nine deuterated species three carbon-13 species and the oxygen-18 species have also been obtained. These data were used to estimate structural parameters by least-squares fitting of the effective moments of inertia. Good agreement with an earlier electron diffraction and ab initio study was obtained. Unassigned transitions from another isomer were observed, presumably the cis, gauche conformer. 相似文献
82.
Saha R Qaium MA Debnath D Younus M Chawdhury N Sultana N Kociok-Köhn G Ooi LL Raithby PR Kijima M 《Dalton transactions (Cambridge, England : 2003)》2005,(16):2760-2765
A series of cis-platinum ethynyl complexes with the general formula cis-[Pt(dppe)(C[triple bond]CR)2](dppe = 1,2-bis(diphenylphosphino)ethane; R = C6H4-p-NO2 1, C6H4-p-CH3 2, C6H4-p-C[triple bond]CH 3 and C6H4-p-C6H4-p-C[triple bond]CH 4) have been prepared by the coupling reaction of cis-[Pt(dppe)Cl2] with two equivalents of the appropriate alkyne. The new complexes have been fully characterized by spectroscopic techniques, and the cis square planar arrangement at the platinum centre has been confirmed by single-crystal X-ray diffraction studies of complexes 1, 2 and 4. The absorption spectra of the complexes 1-4 are dominated by a pi-->pi* band that contains some platinum (n + 1) p orbital character. The position of the band is dependent on the electron donating or withdrawing properties of the ethynyl substituents, R. Complex 1 displays a triplet emission in the green, at room temperature, while complexes 2-4, display singlet emissions in the blue. Again, the difference can be attributed to the nature of the R substituents. 相似文献
83.
The analysis of the orbital interaction between an alkali metal ion and the surrounding solvent molecules is performed for aqueous solutions of Li+, Na+, and K+, by means of the ab initio MO method with the aid of the quantum mechanical (QM)/molecular mechanics (MM) method. A total of 171 water molecules are included for each system. The effect of Li+ orbitals reaches as far as 6 Å 7 Å for Na+; and 9 Å for K+. This effect is caused by the orbital interactions between the valence orbitals of an alkali metal ion and of the surrounding water molecules. The electrostatic interaction and the orbital interaction must not be neglected. The difference in the effect between the alkali metal ions originates from the difference in the valence orbital extensions of the alkali metal ions. 相似文献
84.
The rotational spectra of CD335Cl, CD337Cl, CH336Cl, and CH337Cl in the ν2, ν3, ν5, and ν6 states were observed and analyzed. A few lines of the J = 3 → 2 transition were also detected for 12CD335Cl in the 2ν3 state and for 13CD335Cl in the ν3 state. For CH335Cl in the ν6 state the present data on the J = 1 ← 0 and J = 2 ← 1 transitions were combined with the millimeterwave spectra reported by Sullivan and Frenkel to determine the molecular constants. Special attention was given to the ν2 and ν5 spectra which showed the effect of Coriolis resonance. By transferring some of the constants involved from the laser-Stark spectra we determined B5*, B2*, and q5* for CD3Cl. The large effective q5 constant permitted observation of the direct l-doubling transitions of high J. The analysis of the CH3Cl spectra was much less complete than that on CD3Cl because of limited data. The B rotational constants obtained were compared with the previous microwave and infrared results when available.By using the infrared data on ν1 and ν4 we evaluated the equilibrium Be constants (α4B of CD337Cl was estimated), and refined the equilibrium structure of methyl chloride reported by Duncan. 相似文献
85.
Misako Aida Giorgina Corongiu Enrico Clementi 《International journal of quantum chemistry》1992,42(5):1353-1381
We present a new self-consistent set of ab initio analytical pair potential to predict specific nonbonded interactions of protein with nucleic acid, of protein with protein, and of nucleic acid with nucleic acid. The purpose of this study is to represent the interaction between biological molecules with an accuracy equivalent to the ab initio molecular orbital calculations, which are used as reference data to obtain the pair potentials. Atoms in nucleic acids and proteins are classified according to their chemical environments. An “effective charge,” a modification of a charge obtained from the Mulliken population analysis, is introduced and used to represent the electrostatic energy. More than 30,000 SCF interaction energies have been calculated to provide the reference data for the fitting procedure that we have adopted in the parameterization of the potentials. The standard deviation is 1.61 kcal/mol for interaction energies spanning the range from about ?220 kcal/mol to +20 kcal/mol. Molecular dynamics simulations, using the above new set of force field, have been performed successfully for the systems where adequate treatments of specific interactions are required: The stability of α-helix of C-peptide and the interaction of spermine with oligonucleotide are examined as preliminary examples. 相似文献
86.
Hayato Goto Eduardo Viegas Henrik Jeldtoft Jensen Hideki Takayasu Misako Takayasu 《Journal of statistical physics》2018,172(4):1086-1100
The dynamical phase diagram of a network undergoing annihilation, creation, and coagulation of nodes is found to exhibit two regimes controlled by the combined effect of preferential attachment for initiator and target nodes during coagulation and for link assignment to new nodes. The first regime exhibits smooth dynamics and power law degree distributions. In the second regime, giant degree nodes and gaps in the degree distribution are formed intermittently. Data for the Japanese firm network in 1994 and 2014 suggests that this network is moving towards the intermittent switching region. 相似文献
87.
Takafumi Kitazawa Misako Eguchi Masuo Takeda 《Molecular Crystals and Liquid Crystals》2013,570(2):527-532
Abstract Two-dimensional coordination polymer compounds FeL2Ni(CN)4 (L: 2, 3, or 4-methylpyridine) have been synthesized and characterized by single crystal X-ray diffraction method. 相似文献
88.
We prove three fixed point theorems for generalized contractions with constants in complete metric spaces, which are generalizations of very recent fixed point theorems due to Suzuki. We also raise one problem concerning the constants. 相似文献
89.
90.
Tetsushi Kijima Irakli Javakhishvili Katja Jankova S?ren Hvilsted Shun Kodama Masashi Sugiya Hideo Sawada 《Colloid and polymer science》2012,290(7):589-597
Fluoroalkyl end-capped betaine-type cooligomeric nanocomposites-immobilized palladium nanoparticles were prepared by the reactions
of palladium chloride with sodium acetate in the presence of sodium chloride and the corresponding fluorinated cooligomers.
Outer blocks of poly(2,3,4,5,6-pentafluorostyrene)-containing ABA-triblock copolymeric nanocomposites-immobilized palladium
nanoparticles were prepared by the use of the corresponding block copolymers under similar conditions. TEM images showed that
palladium nanoparticles can be immobilized outside the fluorinated cooligomeric nanocomposite cores; in contrast, palladium
nanoparticles can be effectively immobilized inside these fluorinated ABA-triblock copolymeric nanocomposite cores. Thus,
these two different fluorinated copolymers enabled the controlled immobilization of palladium nanoparticles in the fluorinated
nanocomposite cores. These fluorinated nanocomposites-immobilized palladium nanoparticles were also applied to the catalysts
for Suzuki-Miyaura cross-coupling reaction, and the different reactivity between these nanocomposites was observed. 相似文献