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991.
On Na4(CrO4) Dark-green single crystals of Na4[CrO4] were obtained for the first time. (Na2O/Cr2O3; Na:Cr = 4:1 not exactly closed Ni-tube; 1000°C; 30 d). It is isostructural to Na4(CoO4); space group P1 , a = 859.7 pm, b = 569.8 pm, c = 640 pm, α = 124°C, β = 98.4°, γ = 98.9°, Z = 2. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Effective Ionic Radii, MEFIR, are calculated. 相似文献
992.
A New Cobaltate with Isolated Anion Structure: Li6[CoO4] For the first time transparent, blue single crystals of Li6[CoO4] have been prepared (Li2O/Na2O/?CoO”? (Li:Na:Co = 1.3:1.3:1), Co-tube, 580°C, 22 d). Corresponding to Li6□CoO; it is an ordered variant of the Li2O-type of structure: P42/nmc; a = 653.6(1) pm, c = 465.4(1) pm; Z = 2; dx = 2.75 g cm?3, dpyk = 2.71 g cm?3 (4-circle-diffractometer-data (PW 1100), AgKα; 230 from 936 I0(hkl); R = 9.58%, RW = 5.25%). Parameters see text. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed. The magnetic properties are measured in the temperature range of 14–297 K. 相似文献
993.
The First Oxothallate(III) with the Formula Type AA4′[MO4]: CsK4[TlO4] For the first time CsK4[TlO4] was obtained by heating intimate mixtures of K2O, CdO and CsTl (molar ratio 3.1:1.0:1.0) in closed Ag-cylinders (25 days, 450°C) in form of yellow, transparent single crystals. The structure determination by four circle diffractometer data (MoKα, 1922 out of 2 094 Io(hkl), R = 2.98, Rw = 2.49) confirms the space group Pbca with lattice constants a = 1 192.1 pm; b = 685.7 pm; c = 2 143.5 pm; Z = 8. The structure is isotypic with Na5[GaO4]. The Madelung Part of Lattice Energy, MAPLE, the Mean Fictive Ionic Radii, MEFIR, Effective Coordination Numbers, ECoN, and Charge Distribution, CHARDI, are calculated. 相似文献
994.
Lindner E Schreiber R Schneller T Wegner P Mayer HA Göpel W Ziegler C 《Inorganic chemistry》1996,35(2):514-525
The reaction of two equiv of the monomeric ether-phosphine O,P ligand (MeO)(3)Si(CH(2))(3)(Ph)PCH(2)-Do [1a(T(0)()), 1b(T(0)())] {Do = CH(2)OCH(3) [1a(T(0)())], CHCH(2)CH(2)CH(2)O [1b(T(0)())]} with PdCl(2)(COD) yields the monomeric palladium(II) complexes Cl(2)Pd(P approximately O)(2) [2a(T(0)())(2)(), 2b(T(0)())(2)()]. The compounds 2a(T(0)())(2)() and 2b(T(0)())(2)() are sol-gel processed with variable amounts (y) of Si(OEt)(4) (Q(0)()) to give the polysiloxane-bound complexes 2a(T(n)())(2)()(Q(k)())(y)(), 2b(T(n)())(2)()(Q(k)())(y)() (Table 1) {P approximately O = eta(1)-P-coordinated ether-phosphine ligand; for T(n)() and Q(k)(), y = number of condensed T type (three oxygen neighbors), Q type (four oxygen neighbors) silicon atoms; n and k = number of Si-O-Si bonds; n = 0-3; k = 0-4; 2a(T(n)())(2)()(Q(k)())(y)(), 2b(T(n)())(2)()(Q(k)())(y)() = {[M]-SiO(n)()(/2)(OX)(3)(-)(n)()}(2)[SiO(k)()(/2)(OX)(4)(-)(k)()](y)(), [M] = (Cl(2)Pd)(1/2)(Ph)P(CH(2)Do)(CH(2))(3)-, X = H, Me, Et}. The complexes 2b(T(n)())(2)()(Q(k)())(y)() (y = 4, 12, 36) show high activity and selectivity in the hydrogenation of 1-hexyne and tolan. The dicationic complexes [Pd(P&arcraise;O)(2)][SbF(6)](2) [3a(T(0)())(2)(), 3b(T(0)())(2)()] are formed by reacting Cl(2)Pd(P approximately O)(2) with 2 equiv of a silver salt {P&arcraise;O = eta(2)-O&arcraise;P-coordinated ether-phosphine ligand; 3a(T(0)())(2)(), 3b(T(0)())(2)() = [M]-SiOMe(3); [M] = {[Pd(2+)](1/)(2)P(Ph)(CH(2)CH(2)OCH(3))(CH(2))(3)-}{SbF(6)} (a), {[Pd(2+)](1/)(2)P(Ph)(CH(2)CHCH(2)CH(2)CH(2)O)(CH(2))(3)-}{SbF(6)} (b)}. Their polysiloxane-bound congeners 3a(T(n)())(2)(), 3b(T(n)())(2)() {[M]-SiO(n)()(/2)(OX)(3)(-)(n)} are obtained if a volatile, reversible bound ligand like acetonitrile is employed during the sol-gel process. The bis(chelate)palladium(II) complexes 3a(T(n)())(2)(), 3b(T(n)())(2)() are catalytic active in the solvent-free CO-ethene copolymerization, producing polyketones with chain lengths comparable to those obtained with chelating diphosphine ligands. The polysiloxane-bound palladium(0) complexes 5a(T(n)())(2)()(Q(k)())(4)(), 5b(T(n)())(2)()(Q(k)())(4)() {[M]-SiO(n)()(/)(2)(OX)(3)(-)(n)}(2)[SiO(k)()(/2)(OX)(4)(-)(k)](4), [M] = [(dba)Pd](1/)(2)P(Ph)(CH(2)Do)(CH(2))(3)-} undergo an oxidative addition reaction with iodobenzene in an interphase with formation of the complexes PhPd(I)(P approximately O)(2).4SiO(2) [6a(T(n)())(2)()(Q(k)())(4)(), 6b(T(n)())(2)()(Q(k)())(4)()] {[M]-SiO(n)()(/)(2)(OX)(3)(-)(n)](2)[SiO(k)()(/2)(OX)(4)(-)(k)](4), [M] = [PhPd(I)](1/2)P(Ph)(CH(2)Do)(CH(2))(3)-}, which insert carbon monoxide into the palladium-aryl bond even in the solid state. 相似文献
995.
Two Representatives of the α-LiFeO2 Type: LiInO2 and α-LiYbO2 Single crystals of LiInO2 (well ground mixtures of ‘In2O’: KO2: Li2O = 1:1.8:1, Ag-tube, 22d, 520°C); and α-LiYbO2 (Yb2O3:Li2O = 1:1.1, Ni-tube, 30d, 1150°C) were prepared for the first time from mixtures of the binary oxides. The determination of the structure confirmed the α-LiFeO2 type. Both oxides crystallize in the space group I 41/amd (Z = 4); LiInO2: a = 431.2(1) pm c = 934.2(2) pm; c/a = 2.167; 123 Io(hkl), R = 3.6%, Rw = 2.9%. α-LiYbO2:a = 438.7(1) pm c = 1006.7(2) pm; c/a = 2.295, 130 Io(hkl), R = 4.4%, Rw = 3.6%. The Madelung part of lattice energy, MAPLE and characteristics of this kind of structure are discussed. 相似文献
996.
Rudolf Bock Detlef Jacob Mohamed Fariwar und Klaus Frankenfeld 《Fresenius' Journal of Analytical Chemistry》1964,200(2):80-134
Zusammenfassung Zahlreiche Aufschlußmethoden werden hinsichtlich ihrer Brauchbarkeit für Selenspurenanalysen untersucht und die durch die Flüchtigkeit der Selenverbindungen bedingten Fehlerquellen beseitigt. Von den Anreicherungs- und Trennungsmethoden erwiesen sich die Destillation des Selenbromids, die Mitfällung mit elementarem Tellur und einige Verteilungsverfahren als besonders leistungsfähig. Die Bestimmung von Selenspuren bis zu Mengen von einigen Zehntel Mikrogrammen (und zum Teil noch weniger) ist mit photometrischen, fluorimetrischen und polarographischen Methoden sowie durch Aktivierungsanalyse möglich.
Wir danken Herrn Prof. H. Fink für die Anregung zu dieser Arbeit. Wir verdanken dem Bundesministerium für Wissenschaftliche Forschung großzügige Förderung durch Sachmittel. Wir danken Herrn Prof. F. Strassmann für Überlassung von Geräten und Präparaten zu den radiochemischen Untersuchungen; wir danken Herrn Dr. G. Schrader, Farbenfabriken Bayer AG., Wuppertal-Elberfeld, für Thiophosphorsäureester und den Farbwerken Hoechst AG., Frankfurt a. M.-Höchst, sowie dem Jenaer Glaswerk Schott u. Gen., Mainz, für Analysenproben.
Dissertation Mainz 1963. 相似文献
Summary For the analysis of traces of selenium numerous decomposition methods are tested, and losses due to volatility of selenium compounds are eliminated. The most efficient enrichment and separation methods are distillation of selenium bromide, coprecipitation of selenium with elementary tellurium, and several liquid-liquid extraction methods. The determination of traces of selenium down to a few tenths of a microgram or even less can be effected by photometry, fluorimetry, and polarography, and furthermore by activation analysis.
Wir danken Herrn Prof. H. Fink für die Anregung zu dieser Arbeit. Wir verdanken dem Bundesministerium für Wissenschaftliche Forschung großzügige Förderung durch Sachmittel. Wir danken Herrn Prof. F. Strassmann für Überlassung von Geräten und Präparaten zu den radiochemischen Untersuchungen; wir danken Herrn Dr. G. Schrader, Farbenfabriken Bayer AG., Wuppertal-Elberfeld, für Thiophosphorsäureester und den Farbwerken Hoechst AG., Frankfurt a. M.-Höchst, sowie dem Jenaer Glaswerk Schott u. Gen., Mainz, für Analysenproben.
Dissertation Mainz 1963. 相似文献
997.
On RbNa5Be8O11 For the first time RbNa5Be8O11 was obtained by annealing intimate mixtures of the binary oxides (Rb:Na:Be = 1.1:5.5:8, Ni-cylinder, 650°C, 21d). The compound crystallizes triclinic (P 1 ) with a = 1 063.4 pm, b = 645.6 pm, c = 948.8 pm, α = 110.2º, β = 114.9º, γ = 90.8º, Z = 2. The crystal structure was solved by four-circle-diffractometer data [Siemens AED2, 3099 I0 (hkl), R = 5.1%, Rw = 3.8%]. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, are calculated. 相似文献
998.
A New Perowskite with Deficiencies in the Oxygen Part: Ba4[Na2W2O11] For the first time colourless single crystals of Ba2NaWO5.5 were prepared by reaction of Na4WO5 [2] and ?BaO2”? [Ba:Na:W = 4:4:1, Ni-cylinder, 725°C, 35 d]. Single crystal data [432 of 505 I0 (hkl), Four-circle-diffractometer Siemens AED2, MoKα , R = 6.1%, Rw = 5,6%] verify the space group P mmm with a = 579.16(8), b = 580.85(8), c = 859.4(1) pm, Z = 1. The structure is based upon the CaTiO3-type of structure. Ba2+ take the place of Ca2+ meanwhile Ti4+ is substituted alternately by W6+ and Na+. Complete occupation of all lattice positions would lead to a deficite of positive charge. This is compensate by deficiencies in the oxygen part of the lattice. Related to [Na(1)1Na(2)1W(1)1W(2)1O(1)4O(2)2O(3)2O(4)3] these deficiencies are statistically distributed on O(4). Structural relations are deduced by Schlegel-Diagrams. The Madelung Part of Lattice Energie, MAPLE, Effektive Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed. 相似文献
999.
同步荧光法检测鱼胆汁中的1-羟基芘 总被引:4,自引:0,他引:4
建立了和同步荧光法测定鱼胆汁的1-羟基芘(1-HP)的方法。该方法通过直接测定鱼胆汁的多环芳烃(PAHs)的代谢产物之一1-HP,用于判断PAHs生物有效部分对海岸养殖水环境的污染程度。以真鲷(Pargrosomus major,简称Pm),Mian鱼(Niba miichthys,简称Nm)为实验对象,现场实验结果令人满意。 相似文献
1000.
Fluorides with divalent Silver. On the compounds AgII[MF6] with M = Ge, Sn, Pb, Ti, Zr, Hf, Rh, Pd, Pt. For the first time AgTiF6, AgGeF6, AgSnF6 AgPbF6 (all light-blue), AgRhF6 (black), AgPdF6 (d.brown), AgPtF6 (brownviolet) as well as AgZrF6 and AgHfF6 (both deeply blueviolet) are prepared. AgSnF6, AgPbF6 and AgPdF6 obey the Curie-Weiss Law (m? = 2,0 m?B, small θ-value). In the case of AgZrF6 and AgHfF6 there is a strong magnetic exchange between Ag2+ ions; this may be the cause for the unexpected deep colour. 相似文献