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91.
92.
Swanson SA McClain R Lovejoy KS Alamdari NB Hamilton JS Scott JC 《Langmuir : the ACS journal of surfaces and colloids》2005,21(11):5034-5039
Self-assembled monolayers (SAMs) of the aromatic diisocyanides, 1,4-phenylenediisocyanide, 2,3,5,6-tetramethyl-1,4-phenylenediisocyanide, 4,4'-biphenyldiisocyanide, 3,3',5,5'-tetramethyl-4,4'-biphenyldiisocyanide, and 4,4' '-p-terphenyldiisocyanide, were prepared on gold and palladium surfaces. The SAMs were characterized by ellipsometry, polarization-modulated infrared reflection-absorption spectroscopy (PM-IRRAS), and grazing-angle attenuated total reflectance infrared spectroscopy (GATR). Based on the position of the metal-coordinated isocyanide stretching band, the SAMs on gold were found to bind in the terminal (eta(1)) geometry, while the SAMs on palladium prefer a different geometry which is possibly a triply bridging (mu(3)-eta(1)) geometry. A side-reaction of the unbound isocyanide in the SAM was identified as oxidation to an isocyanate group. 相似文献
93.
94.
95.
Christopher M Timperley Sally A Saunders Josef Szpalek Matthew J Waters 《Journal of fluorine chemistry》2003,119(2):161-171
The reactivity of bis(fluoroalkyl) phosphorochloridates to nucleophiles is summarised. Previous data and the results described here indicate that reactivities decrease in the order: amines>alcohols>thiols. The synthesis of CF3CH2OP(O)(SEt)2 in 30% yield was accomplished by treating CF3CH2OP(O)Cl2 with two molar equivalents of EtSH and Et3N in ether. The chloridates (CF3CH2O)2P(O)Cl and (C2F5CH2O)2P(O)Cl did not react with MeSH in ether at −78 °C or when heated with Pb(SMe)2 in benzene. Ethanethiol and propanethiol reacted with fluorinated chloridates in the presence of triethylamine to give thiolates (RFO)2P(O)SR in 13-41% yield where RF was CF3CH2, C2F5CH2, C3F7CH2 or (CF3)2CH and R was Et or n-Pr. Similarly, reaction of phosphorobromidates (RFCH2O)2P(O)Br, made by brominating the corresponding bis(fluoroalkyl) H-phosphonates, with benzenethiol gave derivatives (RFCH2O)2P(O)SPh in 43 and 46% yield where RF was CF3 and C2F5, respectively. Treatment of the chloridothiolate Cl(EtO)P(O)SMe, prepared in two steps from triethyl phosphite, with fluoroalcohols and triethylamine in ether gave species RFO(EtO)P(O)SMe in 62-74% yield where RF was CF3CH2, C2F5CH2, C3F7CH2 or (CF3)2CH. The reactions of bis(trifluoroethyl) phosphorochloridate with 2-mercaptoethanol, 3-mercaptopropanol and ethane-1,2-dithiol gave several unexpected products whose structures were tentatively assigned. 相似文献
96.
Synthesis and some first-row transition-metal complexes of the 1,2,4-triazole-based Bis(terdentate) ligands TsPMAT and PMAT 总被引:1,自引:0,他引:1
Klingele MH Moubaraki B Murray KS Brooker S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(23):6962-6973
The employment of a strategy based on nucleophilic substitution, rather than Schiff base condensation, for the preparation of 1,2,4-triazole-based ligands has been investigated and has led to the synthesis of two new ligands, 4-amino-3,5-bis{[N-(2-pyridylmethyl)-N-(4-toluenesulfonyl)amino]methyl}-4H-1,2,4-triazole (TsPMAT, 14) and 4-amino-3,5-bis{[(2-pyridylmethyl)amino]methyl}-4H-1,2,4-triazole (PMAT, 15). These are the first examples of bis(terdentate) ligands incorporating the 1,2,4-triazole unit. TsPMAT (14) forms a dinuclear 2:2 complex with Co(BF4)2.6 H2O even when reacted in a metal-to-ligand molar ratio of 2:1. Similarly, the reaction of PMAT (15) with Mn(ClO4)2.6H2O or M(BF4)2.6 H2O (M=Fe, Co, Ni, Zn) in a ligand-to-metal molar ratio of 1:1 has afforded a series of complexes with the general formula [M(II) (2)(PMAT)2]X4. The metal centres in these complexes of TsPMAT (14) and PMAT (15) are encapsulated by two ligand molecules and doubly bridged by the N2 units of the 1,2,4-triazole moieties, which gives rise to N6 coordination spheres that are strongly distorted from octahedral, as evidenced by the X-ray crystal structure analyses of [Co(II) (2)(TsPMAT)(2)](BF(4))(4)6 MeCN (246 MeCN) and [Fe(II) 2(PMAT)2](BF4)4DMF (27DMF). Studies of the magnetic properties of [Co(II) 2(TsPMAT)2](BF4)4.4 H2O (244 H2O), [Mn(II) 2(PMAT)2](ClO4)4 (26), and [Co(II) 2(PMAT)2](BF4)4 (28) have revealed weak antiferromagnetic coupling (J=-3.3, -0.16, and -2.4 cm(-1), respectively) between the two metal centres in these complexes. 相似文献
97.
Kadirvel Manikandan Cardoso Déborah Freeman Sally Brown Gavin 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(2):977-984
Journal of Radioanalytical and Nuclear Chemistry - N-Methyl carbamoylimidazole is a safe and practical alternative to methyl isocyanate for carbamoylation reactions. We have developed a new... 相似文献
98.
Dr. Jesko Koehnke Andrew F. Bent David Zollman Kieran Smith Dr. Wael E. Houssen Dr. Xiaofeng Zhu Greg Mann Dr. Tomas Lebl Richard Scharff Dr. Sally Shirran Dr. Catherine H. Botting Prof. Marcel Jaspars Dr. Ulrich Schwarz‐Linek Prof. James H. Naismith 《Angewandte Chemie (International ed. in English)》2013,52(52):13991-13996
99.
Hydration of aqueous fluoride ions has been studied by theoretical ab initiocalculations in an attempt to understand the experimental Raman spectrum.Calculations for hydrated fluoride, F– (H2O)n where n = 1–10, have been performedat the RHF/6-31 + G* level. A relatively stable geometry exists for n = 6; abovethis number, additional waters hydrogen bond to water of the hydrated fluoride.On the long time scale of the ab initio calculation or experimental diffractionstudies, the average coordination of fluoride is 6. However, it has been possibleto interpret the low-frequency Raman spectrum on the basis of a singlehydrogen-bonded water molecule, F– ... HOH. To rationalize these results, it is proposedthat the average coordination of fluoride is 6, but on the time scale of the Ramanexperiment the fluoride is symmetrically bonded to only one hydrogen of onewater molecule.Chairman and Organizer of the Symposium dedicated to Donald Irish. Unfortunately Murray died during the preparation of this special issue 相似文献
100.
Sally M. McIntyre Jill Wisnewski Ferguson Travis M. Witte R.S. Houk 《Spectrochimica Acta Part B: Atomic Spectroscopy》2011,66(3-4):248-254
The general method of comparing measured ion ratios to calculated ion ratios to determine a gas kinetic temperature (Tgas) is reviewed. Various mathematical refinements to the calculated partition functions are examined for their effect on the determined Tgas. It is found that (a) excited electronic states should be included for ArO+, neutral NO, and O2; (b) a 10% error in solvent load, sample gas flow rate, vibrational constant (ω), rotational constant (B) or measured ion ratio produces only a 1 to 3% error in Tgas; (c) a 10% error in dissociation energy (D0) creates nearly a 10% error in Tgas; and (d) high temperature corrections to the partition functions produce minimal change and can generally be neglected. 相似文献