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41.
Senda S Ohki Y Hirayama T Toda D Chen JL Matsumoto T Kawaguchi H Tatsumi K 《Inorganic chemistry》2006,45(24):9914-9925
A series of [Tm(Me)M(mu-Cl)]2 and Tm(R)MCl (Tm(R) = tris(mercaptoimidazolyl)borate; R = Me, tBu, Ph, 2,6-iPr2C6H3 (Ar); M = Mn, Fe, Co, Ni) complexes have been prepared by treatment of NaTm(Me) or LiTm(R) with an excess amount of metal(II) chlorides, MCl2. Treatment of Tm(R)MCl (R = tBu, Ph, Ar) with NaI led to a halide exchange to afford Tm(R)MI. The molecular structures of [Tm(Me)M(mu-Cl)]2 (M = Mn, Ni), [Tm(Me)Ni(mu-Br)]2, Tm(tBu)MCl (M = Fe, Co), Tm(Ph)MCl (M = Mn, Fe, Co, Ni), Tm(Ar)MCl (M = Mn, Fe, Co, Ni), Tm(Ph)MI (M = Mn, Co), and Tm(Ar)MI (M = Fe, Co, Ni) have been determined by X-ray crystallography. The Tm(R) ligands occupy the tripodal coordination site of the metal ions, giving a square pyramidal or trigonal bipyramidal coordination geometry for Tm(Me)M(mu-Cl)]2 and a tetrahedral geometry for the Tm(R)MCl complexes, where the S-M-S bite angles are larger than the reported N-M-N angles of the corresponding hydrotris(pyrazolyl)borate (Tp(R)) complexes. Treatment of Tm(Ph)2Fe with excess FeCl2 affords Tm(Ph)FeCl, indicating that Tm(R)2M as well as Tm(R)MCl is formed at the initial stage of the reaction between MCl2 and the Tm(R) anion. 相似文献
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5,6-Unsubstituted 1,3-oxazine-2,4-diones ( 3 ) and 6-unsubstituted 5-methyl-1,3-oxazine-2,4-diones ( 4 ) were prepared by reduction of the corresponding 6-chloro derivatives ( 1 and 2 ). Treatment of 6-chloro-3-methyl-1,3-oxazine-2,4-dione ( 1a ) with sodium azide, sodium cyanide, secondary amines and aniline gave the corresponding 6-substituted compounds ( 7, 9, 10 and 11 ) while the reaction of 1a and 2a,b with primary aliphatic amines such as methylamine and ethylamine caused a ring transformation to pyrimidine ring system giving barbituric acids ( 13a-d ). 相似文献
44.
Takayoshi Arai Akitsugu Fujiwara Naota Yokoyama Kenzo Deguchi 《Tetrahedron letters》2006,47(10):1673-1677
Pulse saturation transfer (PST)/MAS was highly effective for enhancing a magic angle spinning (MAS) 13C NMR of the inter-mobile region of polymer supported organic compounds. Direct monitoring of solid-phase synthesis on non-destructed SynPhase lantern was demonstrated using a 7 mm probe on the 13C PST/MAS NMR study. 相似文献
45.
13C NMR spectra of menthol stereoisomers have been determined. The correlations of chemical shifts of these ring carbons with those of stereoisomeric 2-isopropylcyclohexanols are examined. Observed chemical shifts of 1-Me carbons are compared with those predicted from the chemical shifts of stereoisomeric 1-methyl-4-t-butylcyclohexanes. 13C NMR spectra of menthyl acetates, and cis and trans p -menthanes have also been examined. 相似文献
46.
The usefulness of 1,6-dichlorohexane (1,6-DCH) and 1,4-dichlorobutane (1,4-DCB) as organic solvent (O) for ion-transfer voltammetry at O|water (W) interface has been examined, and the results are compared with those with 1,2-dichloroethane (1,2-DCE). The width of potential window of the 0.1 M tetraoctylammonium tetrakis(4-chlorophenyl)borate (O)|0.05 M Li2SO4 (W) interface increased in the sequence: O = 1,6-DCH > 1,4-DCB > 1,2-DCE. The voltammetric behavior of the transfer of various cations and anions at the 1,6-DCH|W and 1,4-DCB|W interfaces has been shown to be of reversible nature, and the midpoint potentials or the reversible half-wave potentials have been determined. The midpoint potentials of hydrophilic ions have also been determined by the analysis of anodic final rise or cathodic final decent of the voltammograms with the O|W interfaces, where the W contains a salt of the hydrophilic ion. Also, the effect of ion-pair formation in O on the midpoint potentials has also been discussed. 相似文献
47.
48.
Tomohito Kameda Toshiaki Yoshioka Miho Uchida Akitsugu Okuwaki 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1503-1506
10.0 wt% milk of lime was added to seawater containing AlCl 3 at Mg/Al molar ratio of 3.0 until pH 10.5 with stirring, and kept at 25;C for 1 h. Hydrotalcite (HT) was precipitated as a single phase, and Mg 2+ and Al 3+ were quantitatively precipitated. The chemical composition was [Mg 0.75 Al 0.25 (OH) 2 ][(SO 4 ) 0.06 (Cl) 0.02 (OH) 0.11 *];0.27H 2 O* (*Balance). A 100 mg-P/L Na 2 HPO 4 solution and the HT were shaken at 25;C. Phosphate removal increased with increasing time and the HT quantity, and was the highest at pH 7-9. Phosphate ion could be quantitatively removed, adding 8 times the stoichiometric quantity of the HT at pH 8.7 for 6 h. 相似文献
49.
50.
2-Methylthio-4-alkenoic esters prepared from 1-alkenes and ethyl methylsulfinylacetate are converted into α,β-unsaturated esters via hydrogenation, oxidation, and thermolysis. This method was applied to the synthesis of queen substance. 相似文献