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101.
B.Mirza M.Mohadesi 《理论物理通讯》2004,42(5):664-668
We study the Dirac and the Klein-Gordon oscillators in a noncommutative space. It is shown that the Klein-Gordon oscillator in a noncommutative space has a similar behaviour to the dynamics of a particle in a commutative space and in a constant magnetic field. The Dirac oscillator in a noncommutative space has a similar equation to the equation of motion for a relativistic fermion in a commutative space and in a magnetic field, however a new exotic term appears, which implies that a charged fermion in a noncommutative space has an electric dipole moment. 相似文献
102.
Diego Venegas‐Yazigi Hameed Mirza A. B. P. Lever Alan J. Lough Juan Costamagna Ramn Latorre 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):e281-e282
The title complex, [Ru(C2H3N)2(C6H6N2)(C18H15P)2](PF6)2.CH4O, is the third of a series of ruthenium complexes containing two triphenylphosphine groups in a trans arrangement, o‐benzoquinone diimine and two other non‐redox active ligands to been characterized. The effect of electron donor–acceptor properties of the two non‐redox active ligands does not change the quinone arrangement for the o‐benzoquinone diimine ligand, as can be seen from the bond distances of the quinone ring. The asymmetric unit contains half a molecule of complex cation (on a twofold rotation axis), one hexafluorophosphate anion and half a molecule of methanol in a general position close to a twofold rotation axis. 相似文献
103.
Diego Venegas‐Yazigi Hameed Mirza A. B. P. Lever Alan J. Lough Juan Costamagna Andrs Vega Ramn Latorre 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):e245-e246
The Ru atom in the title compound, [RuCl2{P(C6H5)3}2{C6H4(NH)2}]·1.33CH3OH·0.33CH2Cl2, shows a six‐coordinate octahedral geometry, with a trans arrangement of the triphenylphosphine groups. One and a half molecules of complex, two molecules of methanol and a half molecule of dichloromethane form the asymmetric unit, with crystallographic twofold rotation symmetry for the complex molecule in a special position. 相似文献
104.
Obesity is the worst health risk worldwide, which is linked to a number of diseases. Pancreatic lipase is considered as an affective cause of obesity and can be a major target for controlling the obesity. The present study was designed to find out best phytochemicals against pancreatic lipase through molecular docking combined with molecular dynamics (MD) simulation. For this purpose, a total of 3770 phytochemicals were docked against pancreatic lipase and ranked them on the basis of binding affinity. Finally, 10 molecules (Kushenol K, Rosmarinic acid, Reserpic acid, Munjistin, Leachianone G, Cephamycin C, Arctigenin, 3-O-acetylpadmatin, Geniposide and Obtusin) were selected that showed strong bonding with the pancreatic lipase. MD simulations were performed on top five compounds using AMBER16. The simulated complexes revealed stability and ligands remained inside the binding pocket. This study concluded that these finalised molecules can be used as drug candidate to control obesity. 相似文献
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107.
This paper deals with a study of stress-concentration factors in finite rectangular plates with rectangular inserts. The paper includes the effects of insert size and its orientation on stress concentrations. Photoelastic models for this investigation are made from hard and soft plastics having different elastic properties. 相似文献
108.
A simulation study has been performed to quantify the effect of volume reduction on the thyroid absorbed dose per decay and to investigate the variation of energy deposition per decay due to β- and γ-activity of ~(131)I with volume/mass of thyroid,for water,ICRP- and ICRU-soft tissue taken as thyroid material.A Monte Carlo model of the thyroid,in the Geant4 radiation transport simulation toolkit was constructed to compute the β- and γ-absorbed dose in the simulated thyroid phantom for various values of its volume.The effect of the size and shape of the thyroid on energy deposition per decay has also been studied by using spherical,ellipsoidal and cylindrical models for the thyroid and varying its volume in 1-25 cm~3 range.The relative differences of Geant4 results for different models with each other and MCNP results he well below 1.870%.The maximum relative difference among the Geant4estimated results for water with ICRP and ICRU soft tissues is not more than 0.225%.S-values for ellipsoidal,spherical and cylindrical thyroid models were estimated and the relative difference with published results lies within3.095%.The absorbed fraction values for beta particles show a good agreement with published values within 2.105%deviation.The Geant4 based simulation results of absorbed fractions for gammas again show a good agreement with the corresponding MCNP and EGS4 results(±6.667%) but have 29.032%higher values than that of MIRD calculated values.Consistent with previous studies,the reduction of the thyroid volume is found to have a substantial effect on the absorbed dose.Geant4 simulations confirm dose dependence on the volume/mass of thyroid in agreement with MCNP and EGS4 computed values but are substantially diiferent from MIRD8 data.Therefore,inclusion of size/mass dependence is indicated for ~(131)I radiotherapy of the thyroid. 相似文献
109.
The quantum vacuum is unstable under the influence of an external electric field and decays into pairs of charged particles, a process which is known as the Schwinger pair production. We propose and demonstrate that this electric field can generate entanglement. Using the Schwinger pair production for constant and pulsed electric fields, we study entanglement for scalar particles with zero spins and Dirac fermions. One can observe the variation of the entanglement produced for bosonic and fermionic modes with respect to different parameters. 相似文献
110.
Superconducting Double Perovskite Bismuth Oxide Prepared by a Low‐Temperature Hydrothermal Reaction
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Mirza H. K. Rubel Prof. Akira Miura Prof. Takahiro Takei Prof. Nobuhiro Kumada M. Mozahar Ali Prof. Masanori Nagao Prof. Satoshi Watauchi Prof. Isao Tanaka Prof. Kengo Oka Prof. Masaki Azuma Prof. Eisuke Magome Prof. Chikako Moriyoshi Prof. Yoshihiro Kuroiwa Prof. A. K. M. Azharul Islam 《Angewandte Chemie (International ed. in English)》2014,53(14):3599-3603
Perovskite‐type structures (ABO3) have received significant attention because of their crystallographic aspects and physical properties, but there has been no clear evidence of a superconductor with a double‐perovskite‐type structure, whose different elements occupy A and/or B sites in ordered ways. In this report, hydrothermal synthesis at 220 °C produced a new superconductor with an A‐site‐ordered double perovskite structure, (Na0.25K0.45)(Ba1.00)3(Bi1.00)4O12, with a maximum Tc of about 27 K. 相似文献