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1.
Aristides Christofides Miguel Ciriano John L. Spencer F. Gordon A. Stone 《Journal of organometallic chemistry》1979,178(1):273-280
The compounds [Pt(C2H4)2(PR3)] [PR3 = P-tBu2Me, P(C6H11)3, PPh3] react dimethyldivinylsilane or dimethyldivinyltin to give chelate complexes [Pt{(CH2CH)2MMe2} (PR3)] (M = Si or Sn). allyltrimethyltin reacts with various diethylene (tertiary phosphine)platinum compounds with cleavage of the allyl group to afford complexes [Pt(SnMe3)(η3-C3H5)(PR2)]. The NMR spectra (13C, 1H and 31P) of the new compounds have been recorded, and the data are discussed in terms of the structures proposed. 相似文献
2.
With the purpose of comparing expectation dipole moment values mu with finite-field obtained dipole moments mu(FF), we recalculated by the finite-field method previously reported mu values of 38 excited states of FeC. In most of the cases mu(FF) is significantly larger than mu. 相似文献
3.
Within an energy range of 2.4 eV, we have explored 29 of the 36 states of the diatomic molecule VC that arise from the atoms in their ground state, V(4s23d3;4F)+C(2s2 2p2;3P). We use multireference methods with large atomic natural orbital basis sets. The ground state is of 2Delta symmetry with the first two excited states, 4Delta and 2Sigma+, located 4.2 and 7.0 kcal/mol above the X state. All the states examined in this work are relatively strongly bound and show significant charge transfer from V to C. The binding energy of the X 2Delta state is estimated to be 95.3 kcal/mol in good agreement with the experimental value. 相似文献
4.
The intrinsically multireference dissociation of the C-N bond in ground-state diazomethane (CH(2)N(2)) at different angles has been studied with the multireference Brillouin-Wigner coupled-cluster singles and doubles (MRBWCCSD) method. The morphology of the calculated potential energy surface (PES) in C(s)() symmetry is similar to a multireference perturbational (CASPT3) PES. The MRBWCCSD/cc-pVTZ H(2)C-N(2) dissociation energy with respect to the asymptotic CH(2)(?(1)A(1)) + N(2)(X(1)Sigma(g)(+)) products is D(e) = 35.9 kcal/mol, or a zero-point corrected D(0) = 21.4 kcal/mol with respect to the ground-state CH(2)(X(3)B(1)) + N(2)(X(1)Sigma(g)(+)) fragments. 相似文献
5.
Jeffrey M. Bergthorson Michael B. Johnson Aristides M. Bonanos Michael Slessor Wei-Jen Su Paul E. Dimotakis 《Flow, Turbulence and Combustion》2009,83(2):269-292
The mixing and flowfield of a complex geometry, similar to a rearward-facing step flow but with injection, is studied. A subsonic
top-stream is expanded over a perforated ramp at an angle of 30°, through which a secondary stream is injected. The mass flux
of the second stream is chosen to be insufficient to provide the entrainment requirements of the shear layer, which, as a
consequence, attaches to the lower guidewall. Part of the flow is directed upstream forming a re-entrant jet within the recirculation
zone that enhances mixing and flameholding. A control-volume model of the flow is found to be in good agreement with the variation
of the overall pressure coefficient of the device with variable mass injection. The flowfield response to changing levels
of heat release is also quantified. While increased heat release acts somewhat analogously to increased mass injection, fundamental
differences in the flow behaviour are observed. The hypergolic hydrogen-fluorine chemical reaction employed allows the level
of molecular mixing in the flow to be inferred. The amount of mixing is found to be higher in the expansion-ramp geometry
than in classical free-shear layers. As in free-shear layers, the level of mixing is found to decrease with increasing top-stream
velocity. Results for a similar configuration with supersonic flow in the top stream are reported in Part II of this two-part
series. 相似文献
6.
Heng Huat Chan Elisavet Konstantinou Aristides Kontogeorgis Chik How Tan 《Finite Fields and Their Applications》2012,18(6):1232-1241
In this article, Ramanujan–Weber class invariants and its analogue are used to derive birthday elliptic curves. 相似文献
7.
Journal of Nanoparticle Research - 相似文献
8.
The Ti(2) and Ti(2)(+) molecular systems have been studied through multireference variational and single reference coupled-cluster methods coupled with large basis sets. Potential energy curves have been constructed for 30 (Ti(2)) and 2 (Ti(2)(+)) states and the usual spectroscopic parameters have been extracted. The main feature of the potential curves is the existence of van der Waals minima (Ti(2)) around 7 bohr irrespective of the molecular symmetry, and 4s(2)-4s(1) interactions (Ti(2)(+)) around 6 bohr. Numerous avoided crossings lead to stronger covalent bonds emanating from 4s(1)-4s(1) atomic distributions. The X-state of the neutral species is formally a (3)Δ(g) state with the first excited state lying within 1 kcal/mol. The removal of the symmetry defining e(-) leads to the X(2)Σ(g)(+) state of Ti(2)(+). 相似文献
9.
W. E. Garner C. A. Waters H. Lüers C. W. G. Hetterschy Aristides Kanitz F. Liebert A. Uhl W. Kestranek J. M. Kolthoff B. D. Hartong J. Pinkhof E. Biilmann A. Klit F. Haber Z. Klemensiewicz W. S. Hughes A. L. v. Steiger W. E. L. Brown Phyllis M. T. Kerridge Th. Arnd W. Siemers K. H. Goode W. D. Treadwell J. W. Williams Th. A. Whitenack U. Ehrhardt und E. Linde 《Fresenius' Journal of Analytical Chemistry》1930,80(5-6):203-213
Ohne Zusammenfassung 相似文献
10.
Szabó T Bakandritsos A Tzitzios V Devlin E Petridis D Dékány I 《The journal of physical chemistry. B》2008,112(46):14461-14469
Loading of graphite oxide (GO) with tris(2,2'-bipyridyl) iron(II) ions and subsequent calcination affords a novel graphene-based composite with magnetic and electrically conductive properties. The pH of the starting aqueous suspension and the washing procedure play a crucial role in the successful immobilization of the iron precursor, which is mainly governed by ion exchange. The complex is intercalated between the graphene oxide layers, where it adopts a distorted conformation. Rapid heating of this solid results in the deflagration of GO and the formation of ultrafine ( d = 2-14 nm) Fe2O3 particles with maghemite as the dominant phase. The superparamagnetic maghemite crystals are dispersed uniformly in the high-surface-area diamagnetic matrix built up from single or turbostratic stacked graphenes. 相似文献