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51.
Aragoni MC Arca M Devillanova FA Hursthouse MB Huth SL Isaia F Lippolis V Mancini A Soddu S Verani G 《Dalton transactions (Cambridge, England : 2003)》2007,(21):2127-2134
The reaction between the coordinatively unsaturated phosphonodithioato complex [Ni(MeOpdt)2] (1) [MeOpdt = (MeO)(4-MeOC(6)H(4))PS2-] and tptz [2,4,6-tris(2-pyridyl)-1,3,5-triazine] has been investigated. Spectrophotometric and conductometric titrations showed the formation of a neutral and an ionic species, i.e. [Ni(MeOdtp)2(tptz)] (2) and [Ni(tptz)2](MeOdtp)2 (3), in correspondence to 1 : 1 and 2 : 1 tptz : ratios, respectively. XRD studies confirmed the formation of both complexes isolated in the compounds 2.MeOH and 3.4H(2)O. In the neutral complex 2 the central Ni(II) ion features a distorted octahedral coordination, achieved through three N-atoms of tptz and three S-atoms belonging to two MeOpdt anions, one of which unexpectedly acts as a monodentate S-donor. In 3.4H(2)O, the two phosphonodithioato anions are non-coordinating and counterbalance the charge of the [Ni(tptz)2](2+) distorted octahedral complex. From the reaction 2 of with I2 and Br2, crystals of [Ni(tptz)2](I3)2 (5) and [Ni(tptz)Br(micro-Br)]2 (6) have been obtained. The dinuclear complex 6 features a structure showing tubular canals with openings of about 6 x 6 A. 相似文献
52.
Raghavendra Kumar P. Ajai K. Singh J. E. Drake M. B. Hursthouse M. E. Little 《Structural chemistry》2007,18(2):203-207
A non-Schiff base (Te, N, O) ligand MeOC6 H4TeCH2CH2NHCH(CH3)C6H4–2–OH (LH) having a chiral center and its palladium(II) complex [PdClL]·CH2Cl2 (1) have been synthesized. Both have characteristic 1H and 13C NMR spectra. The single crystal structure of the complex 1 has been determined by X-ray diffraction methods. The monoclinic crystals of 1 (space group P21/n) have a=14.581(5) Å, b=13.160(5) Å and c=20.249(5) Å, β=99.398(5)°. The Te $\cdots A non-Schiff base (Te, N, O) ligand MeOC6 H4TeCH2CH2NHCH(CH3)C6H4–2–OH (LH) having a chiral center and its palladium(II) complex [PdClL]·CH2Cl2 (1) have been synthesized. Both have characteristic 1H and 13C NMR spectra. The single crystal structure of the complex 1 has been determined by X-ray diffraction methods. The monoclinic crystals of 1 (space group P21/n) have a=14.581(5) ?, b=13.160(5) ? and c=20.249(5) ?, β=99.398(5)°. The TeCl secondary interactions [3.303(2)–3.352(2) ?] between two nearly square planar palladium complex molecules results in a
bimolecular aggregate having a PdPd distance 3.203(1) ?. The Pd–Te, Pd–N and Pd–O bond lengths are 2.5005(7)/2.4914(7), 2.060(4)/2.061(4) and 2.054(3)/2.044(3) ?,
respectively. 相似文献
53.
Simon J. Coles Michael B. Hursthouse David G. Kelly Andrew J. Toner Neil M. Walker 《Journal of organometallic chemistry》1999,580(2):11367
[TiCl2(salen)] (1) reacts with AlMe3 (1:2) to give the heterometallic Ti(III) and Ti(IV) complexes [Ti{(μ-Cl)(AlMe2)}{(μ-Cl)(AlMe2X)}(salen)] (X=Me or Cl) (2) and [TiMe{(μ-Cl)(AlCl2Me)}(salen)] (3). Addition of diethyl ether to 3 affords [Ti(Me)Cl(salen)] (4). The analogous reaction of [TiBr2(salen)] (5) gives the crystallographically characterised [Ti{(μ-Br)(AlMe2)}{(μ-Br)(AlMe2X)}(salen)] (X=Me or Br) (6) and [Ti(Me)Br(salen)] (7) in a single step, whilst the comparable reaction of [TiCl2{(3-MeO)2salen}] (8) with AlMe3 yields [Ti(Me)Cl{(3-MeO)2salen}] (9) with no evidence of titanium(III) species. Reactivity of both halide and methyl groups of 4 has been probed using magnesium reduction, SbCl5 and AgBF4 halide abstraction and SO2 insertion reactions. Hydrolysis of [Ti(Me)X(L)] complexes affords μ-oxo species [TiX(L)]2(μ-O) [X=Cl, L=salen (13); X=Br, L=salen (14); X=Cl, L=(3-MeO)2salen (15)]. 相似文献
54.
55.
Charles M. Marson Jon Campbell Michael B. Hursthouse K. M. Abdul Malik 《Angewandte Chemie (International ed. in English)》1998,37(8):1122-1124
Ring contraction of a 3,4-epoxyalcohol, then lactolization and electrophilic attack are the steps in the domino cyclization protocol for the formation of 8-oxabicyclo[3.2.1]octane systems [Eq. (a)]. 相似文献
56.
Guocheng Zhu Yongning Bian Andrew S. Hursthouse Peng Wan Katarzyna Szymanska Jiangya Ma Xiaofeng Wang Zilong Zhao 《Journal of fluorescence》2017,27(6):2069-2094
Natural organic matter (NOM) found in water sources is broadly defined as a mixture of polyfunctional organic molecules, characterized by its complex structure and paramount influence on water quality. Because the inevitable release of pollutants into aquatic environments due to an ineffective control of industrial and agricultural pollution, the evaluation of the interaction of NOM with heavy metals, nanoparticles, organic pollutants and other pollutants in the aquatic environment, has greatly increased. Three-dimensional (3-D) fluorescence has the potential to reveal the interaction mechanisms between NOM and pollutants as well as the source of NOM pollution. In water purification engineering system, the 3-D fluorescence can indicate the variations of NOM composition and gives an effective prediction of water quality as well as the underline water purification mechanisms. Inadequately treated NOM is a cause of precursors of disinfection byproducts (DBPs), posing a potential threat to human health. Effective control and measurement/evaluation of NOM have long been an important factors in the prevention of water pollution. Overall, 3-D fluorescence allows for a rapid identification of organic components thus indicating possible sources of water pollution, mechanisms of pollutant interactions, and possible DBPs formed during conventional treatment of this water. This article reviews the 3-D fluorescence characteristics of NOM in natural water and typical water purification systems. The 3-D fluorescence was effective for indicating the variabilities in NOM composition and chemistry thus providing a better understanding of NOM in natural water system and water engineering system. 相似文献
57.
Ronson TK Lazarides T Adams H Pope SJ Sykes D Faulkner S Coles SJ Hursthouse MB Clegg W Harrington RW Ward MD 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(36):9299-9313
The complexes [Pt(bipy){CC-(4-pyridyl)}(2)] (1) and [Pt(tBu(2)bipy){CC-(4-pyridyl)}(2)] (2) and [Pt(tBu(2)-bipy)(CC-phen)(2)] (3) all contain a Pt(bipy)(diacetylide) core with pendant 4-pyridyl (1 and 2) or phenanthroline (3) units which can be coordinated to {Ln(diketonate)(3)} fragments (Ln = a lanthanide) to make covalently-linked Pt(II)/Ln(III) polynuclear assemblies in which the Pt(II) chromophore, absorbing in the visible region, can be used to sensitise near-infrared luminescence from the Ln(III) centres. For 1 and 2 one-dimensional coordination polymers [1Ln(tta)(3)](infinity) and [2Ln(hfac)(3)](infinity) are formed, whereas 3 forms trinuclear adducts [3{Ln(hfac)(3)}(2)] (tta=anion of thenoyl-trifluoroacetone; hfac=anion of hexafluoroacetylacetone). Complexes 1-3 show typical Pt(II)-based (3)MLCT luminescence in solution at approximately 510 nm, but in the coordination polymers [1Ln(tta)(3)](infinity) and [2Ln(hfac)(3)](infinity) the presence of stacked pairs of Pt(II) units with short PtPt distances means that the chromophores have (3)MMLCT character and emit at lower energy ( approximately 630 nm). Photophysical studies in solution and in the solid state show that the (3)MMLCT luminescence in [1Ln(tta)(3)](infinity) and [2Ln(hfac)(3)](infinity) in the solid state, and the (3)MLCT emission of [3{Ln(hfac)(3)}(2)] in solution and the solid state, is quenched by Pt-->Ln energy transfer when the lanthanide has low-energy f-f excited states which can act as energy acceptors (Ln=Yb, Nd, Er, Pr). This results in sensitised near-infrared luminescence from the Ln(III) units. The extent of quenching of the Pt(II)-based emission, and the Pt-->Ln energy-transfer rates, can vary over a wide range according to how effective each Ln(III) ion is at acting as an energy acceptor, with Yb(III) usually providing the least quenching (slowest Pt-->Ln energy transfer) and either Nd(III) or Er(III) providing the most (fastest Pt-->Ln energy transfer) according to which one has the best overlap of its f-f absorption manifold with the Pt(II)-based luminescence. 相似文献
58.
Beckett MA Horton PN Hursthouse MB Timmis JL Varma KS 《Dalton transactions (Cambridge, England : 2003)》2012,41(15):4396-4403
The synthesis and characterization of a series of cyclo-alkylammonium pentaborate salts {[cyclo-C(n)H(2n-1)NR(3)][B(5)O(6)(OH)(4)] (R = H, n = 3, 5-7 (1-4); R = Me, n = 6 (5))} are reported. Compounds 1, 2 and 5 have been further characterized by single-crystal XRD studies. Attempted recrystallization of 3 and 4 yielded small crops of the unexpected heptaborate salts, [cyclo-C(6)H(11)NH(3)](2)[B(7)O(9)(OH)(5)]·3H(2)O·B(OH)(3) (6) and [cyclo-C(7)H(13)NH(3)](2)[B(7)O(9)(OH)(5)]·2H(2)O·2B(OH)(3) (7) which were also characterized crystallographically. All compounds show extensive supramolecular H-bonded anionic lattices templated by the cations. H-bond interactions are described in detail. TGA-DSC analysis of the pentaborates 1-5 showed that they thermally decomposed in air at 800 °C to 2.5B(2)O(3), in a 2 step process involving dehydration (<250 °C) and oxidative decomposition (250-600 °C). BET analysis of materials derived from the pentaborates had internal porosities of <1 m(2) g(-1). 相似文献
59.
Simon J. Coles Michael B. Hursthouse 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):e405-e405
The molecular structure of the title compound, C14H14BrF3O2, adopts a bent conformation. Intramolecular O—H?F and intermolecular O—H?O interactions form a bifurcated hydrogen bond which produces a supramolecular assembly of head‐to‐tail dimers. 相似文献
60.
In this study,the three dimensional nanoscale organization in the photoactive layers of poly(3-hexylthiophene) (P3HT) and a methanofullerene derivative (PCBM) is revealed by transmission electron tomography.After annealing treatment,either at elevated temperature or during slow solvent evaporation,nanoscale interpenetrating networks are formed with high crystalline order and favorable concentration gradients of both components through the thickness of the photoactive layer.Such a tailored morphology acco... 相似文献