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排序方式: 共有331条查询结果,搜索用时 187 毫秒
301.
Vanadium(IV) oxide thin films on glass and silicon from the atmospheric pressure chemical vapour deposition reaction of VOCl3 and water 总被引:1,自引:0,他引:1
The dual source atmospheric pressure chemical vapour deposition (APCVD) reaction of VOCl3 and H2O was used to prepare thin films of vanadium oxides on glass and silicon substrates. The thin films were characterised by X-ray diffraction, Raman spectroscopy X-ray photoelectron spectroscopy and scanning electron microscopy. At reactor temperatures above 600 °C with a gas-phase excess of water over VOCl3, vanadium(IV) oxide thin films were produced which show a thermochromic transition temperature of 67 °C. The APCVD process is directly compatible with high throughput float-glass production enabling the use of a thin film of VO2 as an intelligent window coating. With reactor temperatures below 600 °C or with a gas-phase excess of VOCl3 over water, V2O5 thin films were produced. Vanadium(IV) oxide thin films could also be prepared on silicon substrates from the APCVD reaction of VOCl3 and H2O, which opens up further technological applications for the APCVD of VO2 thin films. 相似文献
302.
Hipps KW Scudiero L Barlow DE Cooke MP 《Journal of the American Chemical Society》2002,124(10):2126-2127
The production of a novel two-dimensional bimolecular surface structure using weak noncovalent interactions is demonstrated and observed by scanning tunneling microscopy. This work follows the three-dimensional (3D) ideas of crystal engineering and applies the concepts of supramolecular synthons to molecular systems constrained to 2D by physisorption on a conducting surface. We demonstrate a well-ordered planar structure that self-assembles through the influence of fluorine-phenyl interactions. This study provides a concrete example of the "bottom up" construction of nanostructures and of the systematic design of self-organized layers. To our knowledge, this is the first in a new class of fully 2D materials based both upon weak intermolecular interactions and upon image charges and weak interactions associated with adsorption on metal surfaces. 相似文献
303.
E. L. Charsley P. W. Duke N. J. Manning S. J. Marshall M. Reading 《Journal of Thermal Analysis and Calorimetry》1988,33(1):379-384
A new low temperature differential scanning calorimeter is described which operates over the temperature range –150 °C to 700 °C. The equipment features a chromel heat flux DSC sensor plate located in a cobalt alloy heating chamber, enabling work to be carried out in oxidizing atmospheres to above 600 °C. Full data processing and programme control facilities are provided by an IBM compatible computer system. The performance of the instrument is illustrated by experiments on indium and poly (vinyl chloride).
Zusammenfassung Ein neues Tieftemperatur-Differential-Scanning-Kalorimeter für den Bereich von –120 °C bis+700 °C wird beschrieben. Das Gerät enthält eine Wärmefluss-DSC-Sensorplatte aus Chromel in einer Heizkammer aus einer Kobaltlegierung, was Arbeiten in oxidierender Atmosphäre bis über 600 °C ermöglicht. Ein IBM-kompatibles Computersystem bietet alle Möglichkeiten der Datenverarbeitung und Programmregelung. Die Leistungsfähigkeit des Geräts wird an Hand von Experimenten mit Indium und Polyvinylchlorid demonstriert.
, —150° 700°. , 600°. IBM . .相似文献
304.
C. T. LIN Y. G. CHYAN G. C. KRESHECK HERBERT C. BITTING JR M. A. EL-SAYED 《Photochemistry and photobiology》1989,49(5):641-648
Several spectroscopic techniques (absorption, emission, transient absorption and differential scanning calorimetry--DSC) were used to investigate the deprotonation of dibucaine.HCl in a hydrophobic environment, and the interaction sites and mechanisms of the local anesthetic dibucaine.HCl on bacteriorhodopsin (bR) in purple membrane. The important results are summarized as follows: (1) the visible absorption features of native (lambda max = 568 nm) and deionized (lambda max = 608 nm) bR are sensitive to the amount of dibucaine.HCl added; (2) the emission spectrum of dibucaine.HCl embedded in the retinal-free mutant bR is similar to that of dibucaine free base in Triton X-100 micellar solutions; (3) the phosphorescence emission of dibucaine at 77 K is completely quenched by bR and the fluorescence quenching rate for the incorporated dibucaine.HCl in bR was determined as kq = 4.09 x 10(13) M-1 s-1; (4) the incorporation of dibucaine.HCl in bR inhibits the slow component rate of formation of M412 and decreases the amount of M412 formation in the photochemical cycle of bR; and (5) the thermal stability of native bR was measured by DSC in the presence and absence of dibucaine and yielded an endothermic transition at 95.9 +/- 1.0 degrees C with 13.6 J/g (3.25 +/- 0.12 cal/g) of enthalpy changes. All observations suggest that the action site of the local anesthetic, dibucaine.HCl, is near or at the chromophore, i.e. the retinal Schiff base of bR. The anesthetic action on bR purple membrane is probably via a specific site binding, but not a conformational mechanism. 相似文献
305.
Lopez-Capel E Bol R Manning DA 《Rapid communications in mass spectrometry : RCM》2005,19(22):3192-3198
The simultaneous analysis of evolved gases and the determination of stable isotope composition (delta13C) as part of a thermal analysis experiment have been used to (a) distinguish bulk chemical hosts for carbon (C) and nitrogen (N) within a soil and (b) track labelled C within a soil sequestration experiment. C3 and C4 dung was applied to a pasture soil, and soil samples taken for analysis. The results of thermogravimetry-differential scanning calorimetry-quadrupole mass spectrometry-isotope ratio mass spectrometry (TG-DSC-QMS-IRMS) show that the proportion of more refractory C (lignin-like) is greater for the dungs than for the soil organic matter (SOM), and that this increases with time within the soil. Analysis of evolved gases shows that nitrogen is associated with the decomposition of more refractory C, and is not so strongly associated with the labile C component. IRMS analysis distinguished C3 and C4 dung, and allowed the amount of C from these sources to be estimated for the soil samples. Most dung C enters the refractory SOM fraction. This paper demonstrates the potential of TG-DSC-QMS-IRMS in the investigation of SOM. 相似文献
306.
Paul Conway Seamus M. Grant A.R. Manning F.S. Stephens 《Journal of organometallic chemistry》1980,186(3):C61-C63
[Fe(CO)2 {P(OR)3}2 (SO2)] complexes (R = aryl) exist in solution as equilibrium mixtures of two isomers; both have been shown by X-ray diffraction studies (where R = Ph or o-MeC6H4) to have planar coordination about SO2 and trigonal bipyramidal coordination about Fe, but in one isomer (R = Ph) the equatorial plane is occupied by SO2 and two CO ligands whilst in the other one (R = o-MeC6H4) it is occupied by the SO2 and two P ligands. 相似文献
307.
Alves GA Amato S Anjos JC Appel JA Astorga J Bracker SB Cremaldi LM Dagenhart WD Darling CL Dixon RL Errede D Fenker HC Gay C Green DR Jedicke R Karchin PE Kennedy C Kwan S Lueking LH de Mello Neto JR Metheny J Milburn RH de Miranda JM da Motta Filho H Napier A Passmore D Rafatian A dos Reis AC Ross WR Santoro AF Sheaff M Souza MH Spalding WJ Stoughton C Streetman ME Summers DJ Takach SF Wallace A Wu Z 《Physical review letters》1996,77(12):2392-2395
308.
309.
Robert W. Reed Zuowei Xie Janet Manning Rajeev Mathur Robert Bau Christopher A. Reed 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract The brominated carborane, Br6-CB11 H6- (structure 1) is the most recent candidate for the least coordinating anion. It has wide application to the chemistry of reactive cations. The closest approach to date to the long sought silylium ion, R3Si+, utilized this anion in the structurally characterized compound (i-Pr3Siδ+)(Br6-CB11H6 δ?)1 (structure 2). 相似文献
310.
James R. Manning 《Tetrahedron》2008,64(29):6901-6908
Studies related to the total synthesis of elisabethin C led to the discovery of a rhodium-catalyzed cascade sequence involving isoxazole ring expansion and a [4+3] cycloaddition. The scope of the isoxazole ring expansion was explored, resulting in the synthesis of a range of 2H-1,3-oxazines in 47-96% yield. 相似文献