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1.
The use of liquid fuels such as kerosene is of interest for the pulse detonation engine (PDE). Within this context, the aim
of this work, which is a preliminary study, was to show the feasibility to initiate a detonation in air with liquid-fuel pyrolysis
products, using energies and dimensions of test facility similars to those of PDEs. Therefore, two liquids fuels have been
compared, JP10, which is a synthesis fuel generally used in the field of missile applications, and decane, which is one of
the major components of standard kerosenes (F-34, Jet A1, ...). The thermal degradation of these fuels was studied with two
pyrolysis processes, a batch reactor and a flow reactor. The temperatures varied from 600°C to 1,000°C and residence times
for the batch reactor and the flow reactor were, respectively, between 10–30 s and 0.1–2 s. Subsequently, the detonability
of synthetic gaseous mixtures, which was a schematisation of the decomposition state after the pyrolysis process, has been
studied. The detonability study, regarding nitrogen dilution and equivalence ratio, was investigated in a 50 mm-diameter,
2.5 m-long detonation tube. These dimensions are compatible with applications in the aircraft industry and, more particularly,
in PDEs. Therefore, JP10 and decane were compared to choose the best candidate for liquid-fuel PDE studies.
This paper was based on work that was presented at the 20th International Colloquium on the Dynamics of Explosions and Reactive
Systems, Montreal, Canada, July 31 – August 5, 2005. 相似文献
2.
Kadhim H. Al-Obaidi Robert D. Gillard Leon A. P. Kane-Maguire Peter A. Williams 《Transition Metal Chemistry》1977,2(1):64-66
Summary Bis-(5-nitro-1,10-phenanthroline)platinum(II) dichloride and diperchlorate have been prepared. The reaction between the parent cation and hydroxide ion has been studied using 1 FI n.m.r. spectroscopy and found to involve attack at the ligand. The bis-(2,2-bipyridyl)platinum(II) ion has been shown to be highly reactive towards methoxide ion. The dissociation of a 2,2-bipyridyl ligand is preceded by attack at the ligand.Part XI: R. D. Gillard, t.. A. P. Kane-Maguire and P. A. Williams,Transition Met. Chem., 2, 47 (1977).On leave from the University of Baghdad, Iraq. 相似文献
3.
Base hydrolysis of bis-bipyridylplatinum(II) occurs via a 1:1 intermediate adduct with hydroxide ion. The equilibrium constants for this 1:1 addition of hydroxide inwater to complex ions [PtL2]2+, where L=one of theisoelectronic set 2,2-bipyridyl (bpy); 2,2- bipyrazine (bpz); 3,3-bipyridazine (bpdz) and 2,2- bipyrimidine (bpym) are respectively (as log10K at 25°C): 4.23; 4.59; 3.82; 6.14. This result is rationalized in terms of addition at the 6–position of the ligand. 相似文献
4.
5.
Summary [Fe(3,3'-bipyridazine)3]2+ has a negligible rate of dissociation in water at pH 7, and in 0.05 mol dm–3 HO– at ionic strength 1.00 mol dm–3 (NaNO3) at 298.2 K, the second-order rate constant involving HO– is only 3.3 x 10–5 dm3 mol–1 s–1. Examination of kinetic and other data and results for it wide variety oftris-diimine complexes of FeII related compounds, indicates that dissociation takes placevia attack at the ligand. The significance of the various possible intermediates is assessed and it is evident that a previously postulated intramolecular transfer of HO– from the ligand to the metal atom, with associated metal-nitrogen bond fission, is important in the reaction. A general scheme for dissociation of these kinds of compounds is set out.Part XXX: R. D. Gillard, R. P. Houghton and J. N. Tucker,J. Chem. Soc., Dalton Trans., submitted for publication.Present address: Department of Chemistry. University of Nottingham, University Park, Nottingham NG7 2RD U.K. 相似文献
6.
The quantitative separation of a few mg of strontium and barium from several g of calcium is described. The alkaline earth carbonates are dissolved in 0.1 M EDTA, fixed at pH 4.8 on an ammoniacal Dowex column, and eluted, also with 0.1 M EDTA, calcium at pH 5.25, strontium at pH 6.0, barium at pH 9.0. The end of the calcium elution can be followed accurately by a sudden pH increase in the eluate(from 4.8 upto 5.25). 相似文献
7.
Robert D. Gillard Robert J. Lancashire Peter A. Williams 《Transition Metal Chemistry》1979,4(2):115-118
Summary The reactions of [Fe(bipym)3]2+ and [Ru(bipym)3]2+ with hydroxide ion in aqueous solution have been followed. The [Ru(bipym)3]2+ species undergoes nucleophilic attack at the ligand to yield [Ru(bipym)2(pyrimidine)(OH)]+ and [HCO2]– ion, involving cleavage of one pyrimidyl ring. Intermediates can be observed in the reaction of [Fe(bipym)3]2+ with HO–, N3
– and SCN–. The kinetics of the first reaction have been followed and the results are compared with those known for the reactions of [Fe(bipy)3]2+, [Fe(phen)3]2+ and similar compounds.Part XXIII: P. A. Williams,Transition Met. Chem., 78/84. 相似文献
8.
Charles E. Carraher JR. 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(8):1293-1356
This review emphasizes the breadth of metallic and metallic-like polymers evaluated as to thermal properties. Techniques usefully applied to particular systems are noted with the aim of suggesting their application to other systems. 相似文献
9.
10.
Multireference configuration interaction (MRCI) and complete active space second-order perturbation theory (CASPT2) calculations are performed on Fe2 and Fe? 2. Although it is not possible to definitively identify the ground states of Fe2 and Fe? 2, the calculations suggest that the ground state of Fe? 2 in 8Σ? u derived from 3d134σ2 g4σ2 u and that the states observed in photodetachment are the 9Σ? g and 7Σ? g states with a 3d134σ2 g4σ1 u occupation, but that the ground state of Fe2 is 7Δu(3d144σ2 g) and is not observed in the photo-detachment spectra. 相似文献