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131.
I review recent progress on the electroweak phase transition and baryogenesis, focusing on the minimal supersymmetric Standard
Model as the source of new physics. 相似文献
132.
133.
Yajing Hu Albert Solé-Daura Dr. Yang-Rong Yao Xuechen Liu Dr. Sijie Liu Ao Yu Dr. Ping Peng Prof. Josep M. Poblet Dr. Antonio Rodríguez-Fortea Prof. Luis Echegoyen Prof. Fang-Fang Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(8):1748-1753
The chemistry of cationic forms of clusterfullerenes remain less explored than that of the corresponding neutral or anionic species. In the present work, M3N@Ih-C80 (M=Sc or Lu) cations were generated by both electrochemical and chemical oxidation methods. The as-obtained cations successfully underwent the typical Bingel–Hirsch reaction that fails with neutral Sc3N@Ih-C80. Two isomeric Sc3N@Ih-C80 cation derivatives, [5,6]-open and [6,6]-open adducts, were synthesized, and the former has never been prepared by means of a Bingel–Hirsch reaction with neutral clusterfullerenes. In the case of the Lu3N@Ih-C80 cation, however, only a [6,6]-open adduct was obtained. Density functional theory (DFT) calculations indicated that the oxidized M3N@Ih-C80 was much more reactive than the neutral compound upon addition of the diethyl bromomalonate anion. The Bingel–Hirsch reaction of M3N@Ih-C80 cations occurred by means of an unusual outer-sphere single-electron transfer (SET) process from the diethyl bromomalonate anion to the stable intermediate [M3N@C80(C2H5COO)2CBr].. Remarkably, the diethyl bromomalonate anion was found to act as both a nucleophile and an electron donor. 相似文献
134.
Back Cover: Supramolecular Recognition Influences Magnetism in [X@HVIV8VV14O54]6− Self‐Assemblies with Symmetry‐Breaking Guest Anions (Chem. Eur. J. 6/2015) 下载免费PDF全文
135.
Modular Molecules: Site‐Selective Metal Substitution,Photoreduction, and Chirality in Polyoxometalate Hybrids 下载免费PDF全文
Michele Vonci Fateme Akhlaghi Bagherjeri Peter D. Hall Dr. Robert W. Gable Athanasios Zavras Prof. Richard A. J. O'Hair Yuping Liu Dr. Jie Zhang Dr. Matthew R. Field Dr. Matthew B. Taylor Prof. Johan Du Plessis Prof. Gary Bryant Prof. Mark Riley Dr. Lorenzo Sorace Pablo A. Aparicio Dr. Xavier López Prof. Josep M. Poblet Dr. Chris Ritchie Dr. Colette Boskovic 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(43):14102-14111
The first members of a promising new family of hybrid amino acid–polyoxometalates have emerged from a search for modular functional molecules. Incorporation of glycine (Gly) or norleucine (Nle) ligands into an yttrium‐tungstoarsenate structural backbone, followed by crystallization with p‐methylbenzylammonium (p‐MeBzNH3+) cations, affords (p‐MeBzNH3)6K2(GlyH)[AsIII4(YIIIWVI3)WVI44YIII4O159(Gly)8‐ (H2O)14] ? 47 H2O ( 1 ) and enantiomorphs (p‐MeBzNH3)15(NleH)3 [AsIII4(MoV2MoVI2)WVI44YIII4O160(Nle)9(H2O)11][AsIII4(MoVI2WVI2)‐ WVI44YIII4O160(Nle)9(H2O)11] (generically designated 2 : L ‐Nle, 2 a ; D ‐Nle, 2 b ). An intensive structural, spectroscopic, electrochemical, magnetochemical and theoretical investigation has allowed the elucidation of site‐selective metal substitution and photoreduction of the tetranuclear core of the hybrid polyanions. In the solid state, markedly different crystal packing is evident for the compounds, which indicates the role of noncovalent interactions involving the amino acid ligands. In solution, mass spectrometric and small‐angle X‐ray scattering studies confirm maintenance of the structure of the polyanions of 2 , while circular dichroism demonstrates that the chirality is also maintained. The combination of all of these features in a single modular family emphasizes the potential of such hybrid polyoxometalates to provide nanoscale molecular materials with tunable properties. 相似文献
136.
Sc2O@Td(19151)‐C76: Hindered Cluster Motion inside a Tetrahedral Carbon Cage Probed by Crystallographic and Computational Studies 下载免费PDF全文
Ting Yang Yajuan Hao Laura Abella Qiangqiang Tang Prof. Dr. Xiaohong Li Yingbo Wan Dr. Antonio Rodríguez‐Fortea Prof. Dr. Josep M. Poblet Prof. Dr. Lai Feng Prof. Dr. Ning Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(31):11110-11117
A new cluster fullerene, Sc2O@Td(19151)‐C76, has been isolated and characterized by mass spectrometry, UV/Vis/NIR absorption, 45Sc NMR spectroscopy, cyclic voltammetry, and single‐crystal X‐ray diffraction. The crystallographic analysis unambiguously assigned the cage structure as Td(19151)‐C76, which is the first tetrahedral fullerene cage characterized by single‐crystal X‐ray diffraction. This study also demonstrated that the Sc2O cluster has a much smaller Sc?O?Sc angle than that of Sc2O@Cs(6)‐C82 and the Sc2O unit is fully ordered inside the Td(19151)‐C76 cage. Computational studies further revealed that the cluster motion of the Sc2O is more restrained in the Td(19151)‐C76 cage than that in the Cs(6)‐C82 cage. These results suggest that cage size affects not only the shapes but also the cluster motion inside fullerene cages. 相似文献
137.
Purification of Uranium‐based Endohedral Metallofullerenes (EMFs) by Selective Supramolecular Encapsulation and Release 下载免费PDF全文
Carles Fuertes‐Espinosa Alejandra Gómez‐Torres Roser Morales‐Martínez Dr. Antonio Rodríguez‐Fortea Dr. Cristina García‐Simón Dr. Felipe Gándara Dr. Inhar Imaz Dr. Judith Juanhuix Prof. Daniel Maspoch Prof. Josep M. Poblet Prof. Luis Echegoyen Dr. Xavi Ribas 《Angewandte Chemie (International ed. in English)》2018,57(35):11294-11299
Supramolecular nanocapsule 1 ?(BArF)8 is able to sequentially and selectively entrap recently discovered U2@C80 and unprecedented Sc2CU@C80, simply by soaking crystals of 1 ?(BArF)8 in a toluene solution of arc‐produced soot. These species, selectively and stepwise absorbed by 1 ?(BArF)8, are easily released, obtaining highly pure fractions of U2@C80 and Sc2CU@C80 in one step. Sc2CU@C80 represents the first example of a mixed metal actinide‐based endohedral metallofullerene (EMF). Remarkably, the host–guest studies revealed that 1 ?(BArF)8 is able to discriminate EMFs with the same carbon cage but with different encapsulated cluster and computational studies provide support for these observations. 相似文献
138.
Carbó JJ González-del Moral O Martín A Mena M Poblet JM Santamaría C 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(26):7930-7938
A family of novel titanasiloxanes containing the structural unit {[Ti(eta(5)-C(5)Me(5))O](3)} were synthesized by hydron-transfer processes involving reactions with equimolecular amounts of mu(3)-alkylidyne derivatives [{Ti(eta(5)-C(5)Me(5))(mu-O)}(3)(mu(3)-CR)] (R=H (1), Me (2)) and monosilanols, R(3)'Si(OH), silanediols, R(2)'Si(OH)(2), and the silanetriol tBuSi(OH)(3). Treatment of 1 and 2 with triorganosilanols (R'=Ph, iPr) in hexane affords the new metallasiloxane derivatives [{Ti(eta(5)-C(5)Me(5))(mu-O)}(3)(mu-CHR)(OSiR(3)')] (R=H, R'=Ph (3), iPr (4); R=Me, R'=Ph (5), iPr (6)). Analogous reactions with silanediols, (R'=Ph, iPr), give the cyclic titanasiloxanes [{Ti(eta(5)-C(5)Me(5))(mu-O)}(3)(mu-O(2)SiR'(2))(R)] (R=Me, R'=Ph (7), iPr (8); R=Et, R'=Ph (9), iPr (10)). Utilization of tBuSi(OH)(3) with 1 or 2 at room temperature produces the intermediate complexes [{Ti(eta(5)-C(5)Me(5)) (mu-O)}(3)(mu-O(2)Si(OH)tBu)(R)] (R=Me (11), Et(12)). Further heating of solutions of 11 or 12 affords the same compound with an adamantanoid structure, [{Ti(eta(5)-C(5)Me(5))(mu-O)}(3)(mu-O(3)SitBu)] (13) and methane or ethane elimination, respectively. The X-ray crystal structures of 3, 4, 6, 8, 10, 12, and 13 have been determined. To gain an insight into the mechanism of these reactions, DFT calculations have been performed on the incorporation of monosilanols to the model complex [{Ti(eta(5)-C(5)H(5))(mu-O)}(3)(mu(3)-CMe)] (2 H). The proposed mechanism consists of three steps: 1) hydron transfer from the silanol to one of the oxygen atoms of the Ti(3)O(3) ring, forming a titanasiloxane; 2) intramolecular hydron migration to the alkylidyne moiety; and 3) a mu-alkylidene ligand rotation to give the final product. 相似文献
139.
Valencia R Rodríguez-Fortea A Poblet JM 《The journal of physical chemistry. A》2008,112(20):4550-4555
We analyze the electronic structure of carbide endohedral metallofullerenes of the type Sc(2)C(2)@C(82) and study the possibility of rotation of the encapsulated Sc(2)C(2) moiety in the interior of the cage. Moreover, we rationalize the higher abundance of M(2)C(2)@C(82) (M = Sc, Y) in which the metal-carbide cluster is encapsulated in the C(3v)-C(82):8 carbon cage with respect to other carbides of the same family on the basis of the formal transfer of four electrons from the cluster to the cage and sizeable (LUMO-3)-(LUMO-2) gap in the empty cages. This rule also applies to all those endohedral metallofullerenes in which the encapsulated cluster transfers four electrons to the carbon cage as, for example, the reduced [M@C(82)](-) systems (M = group 3 or lanthanide metal ion). 相似文献
140.