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101.
Spyros P. Perlepes Theodoros F. Zafiropoulos Dimitris Raptis Andreas G. Galinos 《Monatshefte für Chemie / Chemical Monthly》1983,114(12):1355-1358
New complexes of the general types HCo(NCS)3 ·nL, HCoX 2(NCS) ·nL and HCo(NCS)2I ·nL (whereX=Cl, Br, I;L=diethyl ether, pyridine, aniline;n=1.5, 2, 3, 3.5) have been prepared and characterized. The magnetic and spectroscopic data indicate that pseudotetrahedral [Co(NCS)3 L]?, [CoX 2(NCS)L]? and [Co(NCS)2IL]? anions are present in the solid pyridine and aniline compounds. 相似文献
102.
Stamatatos TC Dionyssopoulou S Efthymiou G Kyritsis P Raptopoulou CP Terzis A Vicente R Escuer A Perlepes SP 《Inorganic chemistry》2005,44(10):3374-3376
Aerobic reactions of Co(O(2)CMe)(2).4H(2)O with di-2-pyridyl ketone oxime (Hpko) in the presence of counterions (ClO(4)(-), PF(6-)) give the tetranuclear, mixed-valence cobalt(II/III) clusters [Co(II)(2)Co(III)(2)(OR)(2)(O(2)CMe)(2)(pko)(4)S(2)]X(2) [R = H, S = MeOH, X = ClO(4) (1); R = Me, S = EtOH, X = PF(6) (2)] depending on the solvent mixture. Complexes 1 and 2 are the first Co members in the family of metallacrowns adopting the extremely rare inverse 12-metallacrown-4 motif. 相似文献
103.
Fontenot EJ Lee YH Matthews RD Zhu G Pavlostathis SG 《Applied biochemistry and biotechnology》2003,109(1-3):207-225
The objective of the present study was to assess the biological decolorization of an industrial, spent reactive dyebath and
its three dye components (Reactive Blue 19 [RB 19], Reactive Blue 21 [RB 21], and Reactive Red 198 [RR 198]) under methanogenic
conditions. Using a mixed, methanogenic culture, batch assays were performed to evaluate the rate and exten of color removal
as well as any potential toxic effects. Overall, a high rate and extent of color removal (>10 mg/[L·h] and 88%, respectively)
were observed in cultures amended with either RB19 (an anthraquinone dye) or spent dyebath at an initial dye concentration
of 300 mg/L (expressed as RB 19 equivalent) and 30 g/L of NaCl. Inhibition of acidogenesis and, to a larger degree, of methanogenesis
resulting in accumulation of volatile fatty acids was observed in both RB 19- and spent dyebath-amended cultures. RB 21 (a
phthalocyanine dye) and RR 198 (an azo dye) tested at an initial concentration of 300 mg/L did not result in any significant
inhibition of the mixed methanogenic culture. Based on results obtained with cultures amended with RB 19 with and without
NaCl, as well as a control culture amended with 30 g/L of NaCl, salt was less inhibitory than either RB 19 or the dyebath.
Therefore, the toxic effect of the spent dyebath is at least partially attributed to its major dye component RB 19 and NaCl.
Further testing of the effect of RB 19 decolorization products on the methanogenic activity in the absence of NaCl demonstrated
that these products are much less inhibitory than the parent dye. Although color removal occurred despite the severe culture
inhibition, biological decolorization of full-strength reactive spent dyebaths using methanogenic cultures in a repetitive,
closed-loop system is not deemed feasible. For this reason, a fermentative and halotolerant culture was developed and successfully
used in our laboratory for the decolorization of industrial reactive dyebaths with 100 g/L of NaCl. 相似文献
104.
Andreas G. Galinos Spyros P. Perlepes John K. Kouinis 《Monatshefte für Chemie / Chemical Monthly》1980,111(4):829-839
The preparation, for the first time, and the properties of the title compounds are described. Analytical conductometric, spectral (infrared and ultraviolet) and data from X-ray powder spectra yield information about the probable structure of the complexes in the solid state. The existence of metal-nitrogen bond for all pyridine and aniline complexes, except H2CdI4·4An (An=aniline), is adduced from infrared and far infrared spectral studies.
Etherate, Pyridin- und Anilin-Verbindungen der komplexen Tri- und Tetra-Jodsäuren vonZn(II) undCd(II)
Zusammenfassung Die Darstellung und die Eigenschaften der Titelverbindungen werden erstmalig beschrieben. Analytische und konduktometrische Daten, sowie IR, UV und Röntgenpulveraufnahmen ergaben Informationen, aus denen die wahrscheinliche Struktur der Komplexe im festen Zustand abgeleitet wurde. Die Existenz von Metall—Stickstoff-Bindungen für alle Pyridin- und Anilin-Komplexe, mit Ausnahme von H2CdI4·4An (An=Anilin), ergibt sich aus den Daten von IR und fernem IR.相似文献
105.
Papatriantafyllopoulou C Jones LF Nguyen TD Matamoros-Salvador N Cunha-Silva L Almeida Paz FA Rocha J Evangelisti M Brechin EK Perlepes SP 《Dalton transactions (Cambridge, England : 2003)》2008,(24):3153-3155
The use of pyridine-2-amidoxime in reaction with NiCl2.6H2O in the presence of NaOMe has led to a cationic NiII 12 cluster with novel structural features; each cluster molecule is a ferromagnet with a spin ground state of S = 6 arising from ferromagnetic exchange between the six octahedral NiII ions, but with intercationic interactions also affecting the magnetic properties. 相似文献
106.
Boudalis AK Sanakis Y Clemente-Juan JM Donnadieu B Nastopoulos V Mari A Coppel Y Tuchagues JP Perlepes SP 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(8):2514-2526
Complexes [Fe9(X)2(O2CMe)8{(2‐py)2CO2}4] (X?=OH? ( 1 ), N3? ( 2 ), and NCO? ( 3 )) have been prepared by a route previously employed for the synthesis of analogous Co9 and Ni9 complexes, involving hydroxide substitution by pseudohalides (N3?, NCO?). As indicated by DC magnetic susceptibility measurements, this substitution induced higher ferromagnetic couplings in complexes 2 and 3 , leading to higher ground spin states compared to that of 1 . Variable‐field experiments have shown that the ground state is not well isolated from excited states, as a result of which it cannot be unambiguously determined. AC susceptometry has revealed out‐of‐phase signals, which suggests that these complexes exhibit a slow relaxation of magnetization that follows Arrhenius behavior, as observed in single‐molecule magnets, with energy barriers of 41 K for 2 (τ0=3.4×10?12 s) and 44 K for 3 (τ0=2.0×10?11 s). Slow magnetic relaxation has also been observed by zero‐field 57Fe Mössbauer spectroscopy. Characteristic integer‐spin electron paramagnetic resonance (EPR) signals have been observed at X‐band for 1 , whereas 2 and 3 were found to be EPR‐silent at this frequency. 1H NMR spectrometry in CD3CN has shown that complexes 1 – 3 are stable in solution. 相似文献
107.
Karakalos S Siokou A Dracopoulos V Sutara F Skala T Skoda M Ladas S Prince K Matolin V Chab V 《The Journal of chemical physics》2008,128(10):104705
Photoelectron spectroscopy with synchrotron radiation and low energy electron diffraction (LEED) were used in order to study the MgCl(2)Si(111) system. At submonolayer coverage of MgCl(2), a new LEED pattern was observed corresponding to a (sqr rt 3 x sqr rt 3)R30 degrees overlayer superimposed on the underlying reconstructed Si(111)7 x 7. The surface species at this stage are mainly molecular MgCl(2) and MgCl(x) (x<2) or MgO(x)Cl(y) attached to the Si substrate through Cl bridges coexisting with monodentate SiCl. The interfacial interaction becomes more pronounced when the submonolayer coverage is obtained by annealing thicker MgCl(2) layers, whereby desorption of molecular MgCl(2) is observed leaving on the nonreconstructed silicon surface an approximately 0.2 ML thick MgCl(x) layer which again forms the (sqr rt 3 x sqr rt 3 )R30 degrees superstructure. 相似文献
108.
The prediction of the aerodynamic performance of pitching airfoils in stall conditions is considered in the context of strong viscous–inviscid interaction modelling. The aim of the work is to demonstrate the capabilities of a low‐cost dynamic stall model well suited for engineering applications. The model is formulated on the basis of a standard panel method combined with a vortex blob approximation of the wake. The development of the boundary layer over the airfoil and the evolution of the shear layer in the wake are taken into account by means of strong viscous–inviscid interaction coupling. To this end a transpiration layer is added to the inviscid formulation which represents the displacement effect viscosity results in the flow while the non‐linear coupled equations are solved simultaneously. Separation is modelled by introducing a second wake originating from the separation point (‘double‐wake’ concept) which is provided as part of the boundary layer solution. The theoretical presentation of the model is supported with favourable comparisons to four sets of wind tunnel measurements. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
109.
110.
The reaction of succinamic acid (H2sucm) with Ca(NO3)2·4H2O yielded compounds [Ca(Hsucm)(NO3)(H2O)]n (1) and [Ca(Hsucm)2]n (2). The succinamate(-1) ligand presents two new ligation modes and coordinates through the two carboxylato and the amide O-atoms, thus bridging three CaII ions which assemble into zig-zag 1D chains in 1 and 2D networks in 2. Intermolecular hydrogen bonding interactions in the crystal structures of 1 and 2 result in overall 3D framework structures. Both compounds have been characterized by IR and 1H NMR spectroscopy, and their thermal decomposition was monitored by TG/DTG and DSC measurements. The structural comparison of 1 and 2 with known lanthanide(III) succinamate(-1) complexes reveals differences in the coordination mode of the ligand and in the coordination number of the metal ions; the biological relevance of these differences is discussed. 相似文献