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101.
M. Kamimura 《Nuclear Physics A》1981,351(3):456-480
All the multipole transition densities between the seven T = 0 states in 12C are calculated with the use of the microscopic 3α resonating-group wave functions which are obtained by dynamically solving the 3α relative motion with the total antisymmetrization taken into account exactly. The observed elastic and inelastic electron scattering form factors for the transition to the 21+, 41+, 02+, 11?and 31? states are well reproduced with no additional effective charge. The existence of a deformed intrinsic state for the 01+, 21+and 41+states is deduced by the analysis of the transition densities between them which are derived by the weak-coupling-type 3α wave functions; the intrinsic density distribution is illustrated. The monopole density distribution of the 02+, 22+ and 11?, states is found to be much longer ranged than that of the 01+, 21+ and 41+ states; the 31? state case is intermediate. On the basis of the transition densities between the 01+, 21+, 02+ and 22+ states, analysis is made of the transition between the shell-like states and the molecule-like states with a large spatial-structure change. Specific, effective nucleon-nucleon interactions are folded into the transition densities here obtained. The evident dependence of the radial shape of the folded nucleon-12C form factors on the choice of the interactions and the multi-step form factors for the excitation of the 02+, 11? and 31? states are discussed. 相似文献
102.
The cyclotetraphosphate ion (P(4)O(12)(4)(-)) as a PPN (PPN = (PPh(3))(2)N(+)) salt reacts with [MCl(cod)](2) (M = Rh, Ir; cod = 1,5-cyclooctadiene) to give the dinuclear complexes (PPN)(2)[[M(cod)](2)(P(4)O(12))], in which the two metal moieties are situated trans to each other with respect to the P(4)O(4) ring in the solid state. In solution, however, these complexes exist as mixtures of trans and cis isomers. On the other hand, the P(4)O(12)(4)(-) ion reacts with 4 equiv of [Rh(cod)(MeCN)(x)](+) cation to give the tetranuclear complex [[Rh(cod)](4)(P(4)O(12))], where the four Rh(cod) fragments are bound to the P(4)O(12) platform alternately on both sides of the P(4)O(4) ring. Dinuclear P(4)O(12) complexes of ruthenium and palladium are also synthesized. 相似文献
103.
Noboru Ono Hideyoshi Miyake Akio Kamimura Isami Hamamoto Rui Tamura Aritsune Kaji 《Tetrahedron》1985,41(19):4013-4023
Aliphatic nitro groups are replaced by hydrogen on treatment with tributyltin hydride which proceeds via free radical chain processes. As the nitro group is selectively denitrated and other reducible groups are not affected with tributyltin hydride, this reaction can be used as a method for removing the nitro group from polyfunctional compounds. The radical intermediates generated via denitration can be also used for the carbon-carbon bond forming reactions. 相似文献
104.
Synthesis of 2-benzazepines was readily achieved via 7-endo radical cyclization of N-o-bromobenzylitaconamides or N-o-bromobenzylmethacrylamides which were prepared in two steps from commercially available benzaldehydes, amines, and alpha,beta-unsaturated acids. 相似文献
105.
Akio Kamimura Yuichiro NozakiShingo Ishikawa Ryota InoueMasaharu Nakayama 《Tetrahedron letters》2011,52(4):538-540
K-birnessite, which is readily prepared by the pyrolysis of KMnO4, acts as a convenient new oxidant for benzylic and allylic alcohols. 相似文献
106.
High‐quality Inx Al1–xN (0.71 ≤ xIn ≤ 1.00) nanocolumns (NCs) have been grown on Si(111) substrates by rf‐plasma‐assisted molecular‐beam epitaxy (rf‐MBE). Low‐temperature photoluminescence (LT‐PL) spectra of various In‐rich InAlN NCs were measured at 4 K and single peak PL emissions were observed in the wavelength region from 0.89 µm to 1.79 µm. Temperature‐dependent PL spectra of In0.92Al0.08N NCs were studied and the so‐called “S‐shape” (decrease–increase–decrease) PL peak energy shift was observed with increasing temperature. This shift indicates the carrier localization induced by the In segregation effect and is different from the anomalous blue shift frequently observed in InN films and nanowires with high residual carrier concentra‐ tions. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
107.
108.
Kamimura A Takeuchi R Ikeda K Moriyama T Sumimoto M 《The Journal of organic chemistry》2012,77(5):2236-2245
The one-step preparation of 1-nitrobicyclo[3.1.0]hexane and bicycloisoxazoline-N-oxide was readily achieved from conjugate adducts of nitro alkenes and allylmalonates by treatment with Ag(2)O and iodine under basic conditions. We observed that when a primary alkyl group was present at the β-position of the nitro group, bicyclo[3.1.0]hexane was preferentially formed, whereas if a secondary alkyl group occupied that position, isoxazoline-N-oxide was predominantly produced. High cis-selectivity was observed for the formation of cyclopentane units for both reactions. An iodomethyl adduct, considered an intermediate of the cyclization, was isolated, and its conversion to isoxazoline-N-oxide was successfully achieved. The isoxazoline-N-oxide underwent 1,3-dipolar cycloaddition with alkenes to yield tricycloheterocyclic compounds, which were readily converted to spirolactam in good yield by reductive cleavage of N-O bonds using Raney-Ni. On the other hand, 1,3-dipolar cycloaddition of the isoxazoline-N-oxide to terminal alkynes yielded tricyclic aziridines stereoselectively. 相似文献
109.
We have succeeded in developing a new elasticoluminescent (elastico-L) material SrMg2(PO4)2:Eu (SMPE), which emits purple light clearly observable with the naked eye. SMPE can be synthesized at a firing temperature, which is several hundred degrees Kelvin lower than that for other materials of this group. Based on a comparison between elastico-L emission spectrum and photoluminescence spectrum, the emission was identified to be due to electron transition from an excited state 4f65d1 to the ground state 4f7 in Eu2+ ions. While the emission gradually decayed as stress was applied repeatedly, it recovered completely upon irradiation with UV light (365 nm). This behavior, characteristic to elastico-L materials of the defect-controlled type, suggests that deep charge traps are involved in the emission process. In this paper, the elastico-L mechanism in SMPE is discussed in detail with reference to its thermoluminescence and electroluminescence spectra. 相似文献
110.
A bow shock is observed in a two-dimensional supersonic flow of charged microparticles in a complex plasma. A thin conducting needle is used to make a potential barrier as an obstacle for the particle flow in the complex plasma. The flow is generated and the flow velocity is controlled by changing a tilt angle of the device under the gravitational force. A void, microparticle-free region, is formed around the potential barrier surrounding the obstacle. The flow is bent around the leading edge of the void and forms an arcuate structure when the flow is supersonic. The structure is characterized by the bow shock as confirmed by a polytropic hydrodynamic theory as well as numerical simulation. 相似文献