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181.
Reaction of 3,3′,4,4′-tetramethyl-1,1′-diphosphaferrocene (1) with [Re2(CO)8(CH3CN)2] afforded two trimetallic complexes in which the heterometallocene is ligated across the Re-Re bond. The structure of the complex having 1 bridging the Re2(CO)8 moiety through two P atoms was determined by X-ray diffraction and compared with those of analogous complexes with organic bridging bis-phosphines. The second complex obtained in this reaction presumably contains 1 acting as a (P,Fe) bridging ligand. 相似文献
182.
Jarota A Tondusson M Galle G Freysz E Abramczyk H 《The journal of physical chemistry. A》2012,116(16):4000-4009
A promising material in medicine, electronics, optoelectronics, electrochemistry, catalysis, and photophysics, tetrasulphonated aluminum phthalocyanine (AlPcS(4)), is investigated by means of steady-state and time-resolved pump-probe spectroscopies. Absorption and steady-state fluorescence spectroscopy indicate that AlPcS(4) is essentially monomeric. Spectrally resolved pump-probe data are recorded on time scales ranging from femtoseconds to nanoseconds. The nature of these fast processes and pathways of the competing relaxation processes from the initially excited electronic states in aqueous and organic (dimethyl sulfoxide) solutions are discussed. The decays and bleaching recovery have been fitted in the ultrafast window (0-10 ps) and later time window extending to nanoseconds (0-1 ns). While the excited-state dynamics have been found to be sensitive to the solvent environment, we were able to show that the fast dynamics is described by three time constants in the ranges of 115-500 fs, 2-25 ps, and 150-500 ps. We were able to ascribe these three time constants to different processes. The shortest time constants have been assigned to vibrational wavepacket dynamics. The few picosecond components have been assigned to vibrational relaxation in the excited electronic states. Finally, the 150-500 ps components represent the decay from S(1) to the ground state. The experimental and theoretical treatment proposed in this paper provides a basis for a substantial revision of the commonly accepted interpretation of the Soret transition (B transition) that exists in the literature. 相似文献
183.
184.
Arkadiusz Jadczyk 《Advances in Applied Clifford Algebras》2009,19(1):63-82
In relativistic quantum mechanics wave functions of particles satisfy field equations that have initial data on a space-like
hypersurface. We propose a dual field theory of “wavicles” that have their initial data on a time-like worldline. Propagation
of such fields is superluminal, even though the Hilbert space of the solutions carries a unitary representation of the Poincaré
group of mass zero. We call the objects described by these field equations “Kairons”. The paper builds the field equations
in a general relativistic framework, allowing for a torsion. Kairon fields are section of a vector bundle over space-time.
The bundle has infinite-dimensional fibres. 相似文献
185.
Arkadiusz Bula Sebastian Jurczyk Błażej Chmielnicki Jacek Hulimka Marcin Kozłowski 《International Journal of Polymer Analysis and Characterization》2019,24(2):169-177
The paper presents the results of Dynamic-Mechanical Thermal Analysis (DMTA) for a selected methacrylate adhesive at the frequency range from 1 to 50?Hz and the heating rate of 1 and 3?°C/min, in the range from –70?°C to 180?°C. On the basis of the test results, the glass transition temperature was evaluated for three calculation methods. Master curves were also designated for three different reference temperatures: –20, +20 and +60?°C. Master curves were calculated using shift factors aT - calculated by numerical method. 相似文献
186.
Prochowicz D Justyniak I Kornowicz A Kaczorowski T Kaszkur Z Lewiński J 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(24):7367-7371
The polymer network: The reaction of quinine (QN) with CuI under solvothermal, as well as liquid-assisted grinding, conditions afforded a unique 1D homochiral coordination polymer {[Cu(4)(μ(3)-I)(4)(QN)(2)][Cu(3)(μ(3)-I)(2)(μ(2)-I)(QN)(2)](2)}(n), containing both triangular Cu(3)I(3) and cubane Cu(4)I(4) clusters as connecting nodes (see scheme). Van der Waals interactions between the adjacent 1D polymer chains lead to an extended quasi-honeycomb homochiral pillared 3D network with solvent-free 1D channels. 相似文献
187.
Szeleszczuk Łukasz Gubica Tomasz Szmeja Sebastian Ciesielski Arkadiusz Cyrański Michał K. Pisklak Dariusz M. 《Structural chemistry》2021,32(1):297-307
Structural Chemistry - A reliable method for molecular structure determination, excluding single-crystal X-ray diffraction (SCXRD), has been applied to six methyl glycoside tetrabenzoates. The... 相似文献
188.
Ciesielski A Krygowski TM Cyrański MK 《Journal of chemical information and modeling》2008,48(7):1358-1366
A topological model for estimating the stability of benzenoid hydrocarbons (BHs) is presented showing an acceptable linear dependence on Hess-Schaad resonance energy per pi-electron values. The topological measure of stability is accessible by use of pencil calculation and is based on counting cis-type fragments of double bonds in all canonical structures of a given BH. Evidence is given that infinite chains of straight linear polyacenes are always less stable than the kinked ones. 相似文献
189.
Arkadiusz P. Trawiński 《Few-Body Systems》2016,57(6):449-453
An approximate light-cone wave function for the pion effective quark-antiquark Fock sector corresponding to a small value of the renormalization group parameter is presented. The approximate wave function is motivated by the LF-holography and the quadratic confinement potential in the front form of Hamiltonian dynamics, which is in harmony with the linear confining potential in the instant form. The pion radius, decay constant and form-factor are also presented. 相似文献
190.
Spectrally resolved thermoluminescence (TL) measurements provide a lot of information concerning trapping and recombination states in various dielectric materials. As long-lived luminescence is typically weak, this technique requires a very sensitive apparatus. This paper describes the measurement system that is used for studying spectrally resolved TL and phosphorescence decay in polymers. Exemplary investigations are presented for poly(N-vinylcarbazole) (PVK) thin films. The obtained spectra clearly indicate the influence of solvents (dioxane, chlorobenzene) and excitation wavelengths on TL in PVK samples. 相似文献