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111.
112.
Aihara H Alston-Garnjost M Avery RE Barbaro-Galtieri A Barker AR Barnes AV Barnett BA Bauer DA Bengtsson H Bintinger DL Blumenfeld BJ Bobbink GJ Bross AD Buchanan CD Buijs A Cain MP Caldwell DO Chamberlain O Chien C Clark AR Cowan GD Crane DA Dahl OI Derby KA Eastman JJ Eberhard PH Eisner AM Enomoto R Erné FC Fujii T Gabioud B Gary JW Gorn W Hauptman JM Hofmann W Huth JE Hylen J Joshi UP Kamae T Kaye HS Kees KH Kenney RW Kerth LT Ko W Koda RI Kofler RR Kwong KK Lander RL Langeveld WG Layter JG 《Physical review letters》1986,57(4):404-407
113.
Garst ME Dolby LJ Esfandiari S Fedoruk NA Chamberlain NC Avey AA 《The Journal of organic chemistry》2000,65(21):7098-7104
Reductions of several types of compounds with lithium and ethylenediamine using low molecular weight amines as solvent are described. In all cases 1 mol of ethylenediamine or N, N'-dimethylethylenediamine per gram-atom of lithium was used. In some cases it was beneficial to add an alcohol as a proton donor. These reaction conditions were applied to the debenzylation of N-benzylamide and lactams which are refractory to hydrogenolysis with hydrogen and a catalyst. N-Benzylpilolactam 2, synthesized from pilocarpine hydrochloride in refluxing benzylamine, was debenzylated in good yield using 10 gram-atoms of lithium per mole (10 Li/mol) of 2 in n-propylamine. The debenzylation of N-benzyl-N-methyldecanoic acid amide, 4 (6 Li/mol), in t-butylamine/N, N'-dimethylethylenediamine gave N-methyldecanoic acid amide 6 in 70% yield. Alternatively, reduction of 4 (7 Li/mol) in t-butanol/n-propylamine/ethylenediamine gave n-decanal 12 in 36% yield. Using the same conditions, thioanisole, 1-adamantane-p-toluenesulfonamide, and 1-adamantane methyl p-toluenesulfonate were reduced with 3, 7, and 7.2 Li/mol of compound to give thiophenol (74%), adamantamine (91%), and 1-adamantane methanol (75%), respectively. In this solvent system naphthalene and 3-methyl-2-cyclohexene-1-one were reduced to isotetralin (74%) and 3-methyl cyclohexanone (quantitative) with 5 and 2.2 Li/mol of starting compound, respectively. Oximes and O-methyloximes were reduced to their corresponding amines using 5 and 8 Li/mol of compound, respectively. Anisole was also reduced to 1-methoxy-1,4-cyclohexadiene with 2.5 Li/mol of anisole. Undecanenitrile was reduced to undecylamine with 8.6 Li/mol. Additionally, a base-catalyzed formation of imidazolines from a nitrile and ethylenediamine was also explored. 相似文献
114.
Irving Kuntz Nugent F. Chamberlain 《Journal of polymer science. Part A, Polymer chemistry》1974,12(8):1695-1701
The copolymerization of the zinc chloride complex of acrylonitrile in excess acrylonitrile with α-methylstyrene in the presence of lauroyl peroxide is described. Elemental and proton NMR analyses indicate the equimolar nature of the copolymer product. 13C NMR examination shows that this copolymer is alternating in structure and suggests that the steric placements of the copolymer are random in nature; that complexation does not lead to a stereoselective enchainment mode is the implication of our results. A copolymer which appears to be similar to our product has been prepared by other workers using Al(C2H5)1.5Cl1.5 complexation. Our conclusions regarding copolymer stereoregularity differ from theirs. 相似文献
115.
LIPID PEROXIDATION AND OTHER MEMBRANE DAMAGE PRODUCED IN Escherichia coli K1060 BY NEAR-UV RADIATION AND DEUTERIUM OXIDE 总被引:1,自引:0,他引:1
Abstract— With accumulating evidence that the membrane is an important site for near-UV inactivating events, we have investigated the effects of near-UV radiation on the unsaturated fatty acid auxotroph E. coli K1060 following incorporation into the membrane phospholipids of fatty acids with varying degrees of unsaturation. Sensitivity, lipid peroxidation and membrane damage, as determined by 86 Rb+ leakage, have been found to increase with increasing unsaturation in log-phase cells. Similar experiments carried out in D2 O also show an increase in sensitivity, lipid peroxidation and membrane damage, indicating that singlet oxygen may be responsible for such near-UV-radiation-induced damage 相似文献
116.
A new asymmetric parabolic effective fusion barrier model for heavy ion fusion is developed. 相似文献
117.
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119.
B. E. Cole C. J. G. M. Langerak B. N. Murdin C. D. Bezant J. M. Chamberlain C. R. Pidgeon M. Henini V. Nakov 《Physica E: Low-dimensional Systems and Nanostructures》1998,2(1-4)
We present saturation absorption studies of the HH1→LH1 intersubband transition in a 70 Å p-type GaAs/AlGaAs multi-quantum well. The subband separation in this sample, with strongly non-parabolic bands, varies from 26 meV at k=0 to 16 meV at the Fermi wave vector. The absorption behaviour of this transition is studied over a range of four orders of magnitude of intensity of incident THz radiation. The results are analysed within the contexts of a simple two-level model and an instantaneous thermalization model. The results indicate that the lifetime obtained with these models is limited by the pulsewidth, i.e. is greater than 1.7 ps. This places a lower limit on the energy relaxation time for transitions below the LO-phonon energy. 相似文献
120.
I. Tanihata S. Nagamiya O. Chamberlain M.-C. Lemaire S. Schnetzer G. Shapiro H. Steiner 《Physics letters. [Part B]》1979,87(4):349-353
Energy and angular distributions of π's produced in relativistic heavy-ion collisions have been measured at 800 MeV/A incident energy. Cross sections for low-energy pions (Ecm ≈ 100–200 MeV) are forward and backward peaked in the nucleon-nucleon c.m. frame. Such anisotropy becomes weaker for higher energy pions. The shape of the energy spectra at θcm = 90° is approximately exponential. Their slopes are steeper than those observed for protons. The data are discussed in terms of several models. 相似文献