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81.
We investigate the long-time behavior of viscosity solutions of Hamilton–Jacobi equations in
\mathbbRn{\mathbb{R}^n} with convex and coercive Hamiltonians and give three general criteria for the convergence of solutions to asymptotic solutions
as time goes to infinity. We apply the criteria to obtain more specific sufficient conditions for the convergence to asymptotic
solutions and then examine them with examples. We take a dynamical approach, based on tools from weak KAM theory such as extremal
curves, Aubry sets and representation formulas for solutions, for these investigations. 相似文献
82.
Ichihara T Ishihara M Ohnuma H Niizeki T Satou Y Okamura H Kubono S Tanaka MH Fuchi Y 《Physical review letters》2002,89(14):142501
The charge-exchange reaction 60Ni(13C,13N)60Co at E/A=100 MeV has been studied to locate isovector (deltaT=1) non-spin-flip (deltaS=0) giant resonances. Besides the giant dipole resonance at E(x)=8.7 MeV, another resonance has been observed at E(x)=20 MeV with a width of 9 MeV. Distorted-wave Born approximation analysis on the angular distribution clearly indicated the L=2 multipolarity, attributing the E(x)=20 MeV state to the giant isovector quadrupole resonance. 相似文献
83.
Masami Sawada Masaharu Ichihara Yoshiro Furukawa Yoshio Takai Takashi Ando Terukiyo Hanafusa 《Tetrahedron letters》1982,23(31):3181-3184
The reaction of 4-pyridone or 4-quinolone with methyl or benzyl isocyanate in the presence of triethylamine or 1,1,3,3-tetramethylguanidine base gave the corresponding 1,3,5-triazine derivative (e. g., II) in a good yield via stepwise additions. 相似文献
84.
We have presented the optimal control theory formulation to calculate optimal fields that can control the full ensemble of randomly oriented molecules having different field-free Hamiltonians. The theory is applied to the fifty-fifty mixture of randomly oriented (133)CsI and (135)CsI isotopomers and an optimal field is sought to achieve isotope-selective vibrational excitations with high efficiency. Rotational motion is frozen and two total times (T's) of electric field duration, 460,000 and 920,000 a.u. (11.1 and 22.2 ps), are chosen in the present calculation. As a result, the final yields for T = 460,000 and 920,000 a.u. are calculated to be 0.706 and 0.815, respectively. The relatively high final yield obtained for T = 920,000 a.u. strongly suggests that a single laser pulse can control the full ensemble of randomly oriented non-identical molecules. The result is quite encouraging in terms of the application to isotope-separation processes. 相似文献
85.
Mingdeng Wei Kewei Wei M. Ichihara Haoshen Zhou 《Electrochemistry communications》2008,10(8):1164-1167
In this study, H2Ti3O7 nanowires were successfully synthesized via a hydrothermal process and post-treatments. The diameter of the nanowires is found to be about 30 nm and the length up to several micrometers. A lithium battery using H2Ti3O7 nanowires as the active material of the positive electrode exhibits a discharge capacity of 100 mA hg−1 and still keeps stable after 200 cycles at a current density as high as 40 Ag−1, demonstrating excellent high rate performance. 相似文献
86.
Akitami Ichihara Yasuji Nakamura Hirokazu Kawagishi Sadao Sakamura 《Tetrahedron letters》1979,20(39):3735-3736
The absolute configuration of lappaol A and F was determined by the correlation of the ozonolysis products with 2R,3R-(?)-dicarbomethoxymethyl-γ-butyrolactone and S-(?)-methyl paraconate. 相似文献
87.
88.
Murata N Fujimori S Ichihara Y Sato Y Yamaji T Tsuboi H Uchida M Suzuki H Yamada M Oikawa T Nemoto H Nobuhiro J Choshi T Hibino S 《Chemical & pharmaceutical bulletin》2006,54(11):1567-1570
We synthesized 9alpha-fluoromedroxyprogesterone acetate (FMPA) in order to test whether it is a more potent anti-angiogenic agent than medroxyprogesterone acetate (MPA), which has been widely used as a therapeutic agent for breast and endometrium cancers. FMPA was previously synthesized in 10 steps (total yield: 1%). An efficient synthesis of FMPA has been achieved in 6 steps (total yield: 12%). We examined the anti-tumor effect of FMPA, complexed with dimethyl-beta-cyclodextrin (DM-beta-CyD), on rat mammary carcinomas induced by 7,12-dimethylbenz[a]anthracene (DMBA). FMPA showed great anti-tumor effect on DMBA-induced rat mammary carcinomas. 相似文献
89.
Hayakawa S Kitaguchi A Kameoka S Toyoda M Ichihara T 《The Journal of chemical physics》2006,124(22):224320
Doubly charged tungsten hexacarbonyl W(CO)(6) (2+) ions were made to collide with Ar and K targets to give singly and doubly charged positive ions by collision-induced dissociation (CID). The resulting ions were analyzed and detected by using a spherical electrostatic analyzer. Whereas the doubly charged fragment ions resulting from collisional activation (CA) were dominant with the Ar target, singly charged fragment ions resulting from electron transfer were dominant with the K target. The internal energy deposition in collisionally activated dissociation (CAD) evaluated with the Ar target was broad and decreased with increasing internal energy. The predominant peaks observed with the K target were associated with singly charged W(CO)(2) (+) and W(CO)(3) (+) ions: these ions were not the result of CA, but arose from dissociation induced by electron transfer (DIET). The internal energy deposition resulting from the electron transfer was very narrow and centered at a particular energy, 7.8 eV below the energy level of the W(CO)(6) (2+) ion. This narrow internal energy distribution was explained in terms of electron transfer by Landau-Zener potential crossing at a separation of 5.9 x 10(-8) cm between a W(CO)(6) (2+) ion and a K atom, and the coulombic repulsion between singly charged ions in the exit channel. A large cross section of 1.1 x 10(-14) cm(2) was estimated for electron capture of the doubly charged W(CO)(6) (2+) ion from the alkali metal target, whose ionization energy is very low. The term "collision-induced dissociation," taken literally, includes all dissociation processes induced by collision, and therefore encompasses both CAD and DIET processes in the present work. Although the terms CID and CAD have been defined similarly, we would like to propose that they should not be used interchangeably, on the basis that there are differences in the observed ions and in their intensities with Ar and K targets. 相似文献
90.
We study the long time behavior of viscosity solutions of the Cauchy problem for Hamilton–Jacobi equations in ? n . We prove that if the Hamiltonian H(x, p) is coercive and strictly convex in a mild sense in p and upper semi-periodic in x, then any solution of the Cauchy problem “converges” to an asymptotic solution for any lower semi-almost periodic initial function. 相似文献