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51.
Glen B. Deacon Catharina C. Quitmann Klaus Müller‐Buschbaum Gerd Meyer 《无机化学与普通化学杂志》2003,629(4):589-591
Transparent orange crystals of [Yb(MeCp)2(O2CC6F5)]2 and [Yb(MeCp)2(O2C‐o‐HC6F4)]2 were obtained by oxidation of Yb(MeCp)2 with M(O2CR) (M = 1/2 Hg, Tl; R = C6F5, o‐HC6F4) in tetrahydrofuran. They have a dimeric structure with bridging bidentate (O, O')‐benzoate groups and eight coordinated ytterbium. Both crystallise isotypic in the orthorhombic space group Pbca. Room temperature as well as low temperature single crystal X‐ray investigations show the o‐H/F positions in [Yb(MeCp)2(O2C‐o‐HC6F4)]2 not to be ordered. 相似文献
52.
The acetatobis(polyfluorophenyl)thallium(III) compounds R2TlO2CCH3 (R = C6F5, -HC6F4, or -HC6F4) have been prepared by sulphur dioxide elimination reactions from the appropriate lithium polyfluorobenzenesulphinates and thallic trifluoroacetate or acetate under mild conditions. Owing to reduction of the thallic salt by liberated sulphur dioxide, good yields required the stoichiometry 2LiO2SR: 3TlX3 (X = O2CCF3 or O2CCH3). The reactions are considered to proceed via thallium(III) -sulphinate complexes and a possible mechanism is discussed. 相似文献
53.
Summary The platinum(II) carboxylates,trans-Pt(O2CR)2(py)2 and Pt(O2CR)2bpy (R=C6F5,p-HC6F4,m-HC6F4, oro-HC6F4; bpy=2,2-bipyridyl), have been prepared by reactions oftrans-Pt(OH)2(py)2 or Pt(OH)2bpy with the appropriate polyfluorobenzoic acids, whilst [Pt(py)4](O2CC6F5)2 has been obtained from reaction oftrans-PtCl2(py)2 with thallous pentafluorobenzoate in pyridine at room temperature. In boiling pyridine, the platinum(II) polyfluorobenzoates undergo either decarboxylation givingtrans-PtR2(py)2 and PtR2bpy (R= C6F5,p-HC6F4, orm-HC6F4) complexes or substitution, giving [Pt(py)4](O2CC6F4H-o)2 and [Ptbpy(py)2](O2CC6F4H-o)2. Reactions oftrans-PtX2(py)2 and PtX2bpy (X=Cl or Br) with appropriate thallous polyfluorobenzoates in boiling pyridine have yielded the complexestrans-PtR2(py)2, PtR2bpy, PtCl(R)bpy (R=C6F5,p-HC6F4, orm-HC6F4 in each case),trans-PtCl(R)(py)2 (R = C6F5 orm-HC6F4),trans-PtBr(C6F5)(py)2, and PtBr(C6F5)bpy. The complexestrans-PtR2(py)2 (R=C6F5 orp-HC6F4) have also been prepared from potassium tetrachloroplatinate(II) and the appropriate thallous polyfluorobenzoate in boiling py, andtrans-Pt(C6F5)2(py)2 has been similarly obtained fromcis-PtCl2(py)2 and C6F5CO2Tl. Significant decarboxylation was not observed on reaction oftrans-PtCl2(py)2 or PtCl2bpy with thallous 2,3,4,5-tetrafluorobenzoate.Part II, ref. 4;Preliminary communication, ref. 3; 相似文献
54.
55.
Carmel T. Abrahams Rachel Blackshaw Glen B. Deacon Bryan M. Gatehouse Gerald Henkel Ralf Herkelmann Ralf Jüschke Anna Philosof Petra Rieland Peter Sartori 《无机化学与普通化学杂志》2000,626(9):2012-2019
The barium perfluoroalkanedisulfonates Ba(O3S)2(CF2)n (n = 1, 3–5) and the new potassium fluoroalkanedisulfonates K2(O3S)2CHF, K2(O3S)2CF2, and K2(O3S)2(CF2)5 have been prepared by reaction of (CF2)n(SO2F)2 (n = 1, 3–5) or CHF(SO2F)2 with CaO (or Ca(OH)2) and M(OH)x (M = Ba, x = 2; M = K, x = 1) or with Ba(OH)2 alone (n = 1) in water. In each of the crystal structures of K2(O3S)2CHF and K2(O3S)2CF2, there is an eight‐coordinate and a six‐coordinate potassium ion, whilst in K2(O3S)2(CF2)3H2O, two different eight‐coordinate potassium ions are linked by a bridging water molecule. One potassium has additionally six sulfonate oxygen and one fluorine donor atoms, and the other, five sulfonate oxygens and two fluorine donor atoms. The preparation of highly crystalline [Nien3][(O3S)(CF2)n] (en = ethane‐1,2‐diamine; n = 1, 3–5) and the X‐ray crystal structures for n = 1 or 3 provide evidence for the value of perfluoroalkanedisulfonate ions as counter ions for the crystallization of cationic complexes. 相似文献
56.
Glen B. Deacon Catharina C. Quitmann Klaus Müller‐Buschbaum Gerd Meyer 《无机化学与普通化学杂志》2001,627(7):1431-1432
Transparent orange‐red crystals of [Yb(MeCp)2(O2CPh)]2 obtained by oxidation of Yb(MeCp)2 with Tl(O2CPh) in tetrahydrofuran have a dimeric structure with bridging bidentate (O,O′)‐benzoate groups and eight‐coordinate ytterbium. 相似文献
57.
58.
[Yb(OAr)2(μ‐OMe)(DME)]2 ( 1 ) (OAr = 2,6‐di‐iso‐propylphenolate) was synthesised via a redox transmetallation ligand exchange reaction between ytterbium metal, diphenylmercury and 2,6‐di‐isopropylphenol in DME. The source of the methoxy groups is from cleavage of DME, and the C‐O bond activation is unexpected given that the reaction was undertaken at ambient temperature. Each Yb3+ metal ion in 1 is six coordinate, and the coordination arrangement around each metal ion is distorted trigonal antiprismatic with Yb‐O(OMe) bond lengths (2.191(2) and 2.258(2) Å) shorter than the Yb‐O(aryloxide) bond distances (2.094(2) and 2.074(2) Å). 相似文献
59.
60.
Nicolas Delerue Sudhir Dixit Fred Gannaway David Howell Myriam Qurshi Grahame Blair Stewart Boogert Gary Boorman Chafik Driouichi Lawrence Deacon Alexander Aryshev Pavel Karataev Nobuhiro Terunuma Junji Urakawa Axel Brachmann Joe Frisch Marc Ross 《Pramana》2007,69(6):1147-1150
A new laser-wire has been installed in the extraction line of the ATF at KEK. It aims at demonstrating that laser-wires can
be used to measure micrometre scale beam size. In parallel, studies have been made to specify a laser suitable for the ILC
laser-wires.
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