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131.
132.
The evolution equations for a phase interface are discussed. Interfacial structure is neglected, as are thermal and compositional variations. The focus is on a new treatment of the inertial forces at the interface. 相似文献
133.
Aaron P. Holm Susan M. Kauzlarich Simon A. Morton James G. Tobin 《Journal of solid state chemistry》2005,178(1):262-269
Measurements of core and valence electronic states of single crystals of the rare earth transition metal Zintl phases Yb14MnSb11 and Yb14ZnSb11 were performed using the X-ray photoelectron spectroscopy station of Beamline 7 at the Advanced Light Source. Sample surfaces of Yb14MnSb11 and Yb14ZnSb11 were measured as received, after Ar+ ion bombardment, and after cleaving in situ. The single crystal structure of Yb14ZnSb11 is also reported. Both compounds are air-sensitive and show Yb3+ due to surface oxidation. In the case of Yb14MnSb11, there is no evidence for Yb3+ that would be intrinsic to the sample, consistent with previously reported X-ray magnetic circular dichroism studies. Detailed analyses of the Yb14ZnSb11 surfaces reveal a significant contribution of both Yb3+ and Yb2+ 4f states in the valence band region. This result is predicted for the Zn analog by Zintl counting rules and support the mixed valency of Yb for Yb14ZnSb11. Further detailed analysis of the core and valence band structure of both Yb14MnSb11 and Yb14ZnSb11 is presented. 相似文献
134.
Ward M. Scott Morton E. Wacks C. D. Eskelson J. C. Towne C. Cazee 《Journal of mass spectrometry : JMS》1968,1(6):847-855
The mass spectra of various ring-substituted salicylic acids and derivatives thereof have been examined. Fragmentation pathways for derivatives of salicylic acid; 3-NO2 salicylic acid; 5-I salicylic acid; 3-NO2, 5-I salicylic acid; and 3-NH2, 5-I salicylic acid are suggested. The major dissociations of these compounds are by elimination of the elements of neutral molecules, e.g. water, methanol, ketene (from the acetylated compounds) carbon monoxide, nitric oxide and nitrogen dioxide, leading to (iodo) phenoxy and (iodo) quinone type ion structures. These ions further decompose to yield the corresponding substituted cyclopentadienyl and cyclopropylium ions. 相似文献
135.
Ion-neutral complexes, well attested as intermediates in the expulsion of alkenes from M+? and MH+ ions from primary alkyl phenyl ethers, are shown to intervene in the decomposition of the MH+ ion of a secondary alkyl phenyl ether, (CD3)2CHOPh. Chemical ionization (CI) (methane reagent gas)-mass-analysed ion kinetic energy spectroscopy (MIKES) shows ions of both m/z 96 and 97, indicating that the proton deposited by the CI reagent exchanges with the methyl deuterium atoms. The ratio of daughter ion intensities, as well as the proportions of ions of m/z 95, 96 and 97 from the MH+ of CD3CH2CD2OPh, agree with predictions based on the gas-phase solvolysis mechanism, in which [i-Pr+ PhOH] complexes form from the protonated parent via simple bond heterolysis. An alternative mechanism, elimination-readdition, would proceed via [propene PhOHD+] complexes. This latter mechanism predicts a ratio of daughter ion intensities that is very different from gas-phase solvolysis and which disagrees with experiment. The elimination-readdition pathway is effectively ruled out, while the gas-phase solvolysis mechanism is reinforced. 相似文献
136.
Morton H. Litt Jinbaek Kim Jos M. Rodriguezparada 《Journal of polymer science. Part A, Polymer chemistry》1985,23(5):1307-1319
Two new N-substituted polyethylenimines containing carbazole and acridone groups on the side chains were prepared. The polymers were obtained by cationic ring opening polymerization of the corresponding 2-oxazoline monomers. The carbazole containing oxazoline was low melting and could be polymerized in bulk; however the acridone containing monomer had a high melting point and solution polymerization had to be used. This paper describes the synthetic procedures used to obtain these polymers. 相似文献
137.
Tianhong Zhang Morton H. Litt Charles E. Rogers 《Journal of polymer science. Part A, Polymer chemistry》1994,32(8):1531-1537
Eight poly(urethane-sulfone)s were synthesized from two sulfone-containing diols, 1,3-bis(3-hydroxypropylsulfonyl)propane (Diol-333) and 1,4-bis(3-hydroxypropylsulfonyl)butane (Diol-343), and three diisocyanates, 1,6-hexamethylene diisocyanate (HMDI), 4,4′-diphenylmethane diisocyanate (MDI), and tolylene diisocyanate (TDI, 2,4- 80%; 2,6-20%). As a comparison, eight polyurethanes were also synthesized from two alkanediols, 1,9-nonanediol and 1,10-decanediol, and three diisocyanates. Diol-333 and Diol-343 were prepared by the addition of 1,3-propanedithiol or 1,4-butanedithiol to allyl alcohol and subsequent oxidation of the resulting sulfide-containing diols. The homopoly(urethanesulfone)s from HMDI and MDI are semicrystalline, and are soluble in m-cresol and hot DMF, DMAC, and DMSO. The copoly(urethane-sulfone)s from a 1/1 molar ratio mixture of Diol-333 and Diol-343 with HMDI or MDI have lower crystallinity and better solubility than the corresponding homopoly(urethane-sulfone)s. The poly(urethane-sulfone)s from TDI are amorphous, and are readily soluble in m-cresol, DMF, DMAC, and DMSO at room temperature. Differential scanning calorimetry data showed that poly(urethane-sulfone)s have higher glass transition temperatures and melting points than the corresponding polyurethanes without sulfone groups. The rise in glass transition temperature is 20–25°C while the rise in melting temperature is 46–71°C. © 1994 John Wiley & Sons, Inc. 相似文献
138.
Mössbauer resonance has been used to study a single crystal of FeCl3·6H2O at 1.16°K in external magnetic fields. The spectra exhibit pronounced splittings of the resonance lines at low field, followed by compression and then expansion of the resonance spectrum with increasing field. The results demonstrate two unique sets of ionic spins, and a gradual transformation from an antiferromagnetic state to magnetically induced paramagnetism. 相似文献
139.
Mohamed F. Meidine Catherine J. Meir Stephen Morton John F. Nixon 《Journal of organometallic chemistry》1985,297(2):255-263
Syntheses of the complexes trans-[PtCl2(PR3)Mo2(CO)4(η5-C5H5)2(tBuCP)], (PR3=PEt3, PPr3, PBu3, PPh2Me, PPhMe2) trans-[PdCl2(PBu3)Mo2(CO)4(η5-C5H5)2(tBuCP)], and trans[RhCl{(PF2NMe)2CO}Mo2(CO)4(η5-C5H5)2(tBuCP)] are described and their 31P NMR spectra presented and discussed. 相似文献
140.
Yvan Guindon Christiane Yoakim Michael A. Bernstein Howard E. Morton 《Tetrahedron letters》1985,26(9):1185-1188
The synthesis of Ethyl 5(S),6-Epoxy-3(R)-(methoxymethoxy)hexanoate, a key chiral synthon for the β-hydroxy-δ-lactone portion of Mevinolin and Compactin, a regiospecific ring opening of a tetrahydrofuran derivative by dimethylboron bromide, is described. 相似文献