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71.
A high performance liquid chromatographic method was developed for quantifying blends of biodiesel (simple alkyl esters of fatty acids) in petrodiesel. The method uses a silica column with an isocratic mobile phase consisting of hexane and methyl t-butyl ether. Separated components were quantitated using either an evaporative light scattering detector (ELSD) or UV detector. Precision of injection and linearity of response of the ELSD and UV detectors over a range of biodiesel-petrodiesel blends [1–30 v/v %] were established by use of standards. The method also can be used for quantitating similar levels of oils or fats (triacylglycerols) in petrodiesel. 相似文献
72.
Phillips John R. Clausen Edgar C. Gaddy James L. 《Applied biochemistry and biotechnology》1994,45(1):145-157
Synthesis gas provides a simple substrate for the production of fuels and chemicals. Synthesis gas can be produced via established technologies from a variety of feedstocks including coal, wood, and agricultural and municipal wastes. The gasification is thermally efficient and results in complete conversion of the feedstock to fermentable substrate.Clostridium ljungdahlii grows on the synthesis gas components, carbon monoxide, hydrogen, and carbon dioxide. Production of acetic acid and ethanol accompanies growth with synthesis gas as sole source of energy and carbon. Rate and yield parameters are compared forC. ljungdahlii grown on carbon monoxide, or hydrogen with carbon dioxide.
相似文献73.
John Phillips 《Journal of Functional Analysis》1983,51(3):259-267
Let B be a unital C1-algebra and A = Γ(E) be the C1-algebra of sections of a bundle over the separable compact space X with fibre B and structure group Inn B. If B is the quotient of an AW1-algebra, then an exact sequence: 0 → Inn A → PInn A →ηH2(X, G), where PInn A is the group of pointwise inner automorphisms of A and G=H°(Z(B)^, ) is obtained. The map η is onto whenever A = C(X, B) and B is the quotient of a purely infinite AW1-algebra. An essential part of the analysis is the result that Ad: U(B) → Inn B is a fibre bundle if and only if the space of inner derivations of B is norm closed. These results extend and clarify previous joint work with I. Raeburn (Indiana Univ. Math. J.29 (1980), 799). 相似文献
74.
Chiu-Hong Lin Michael D. Ennis Robert L. Hoffman Gillian Phillips Susanne R. Haadsma-Svensson Nabil B. Ghazal Connie G. Chidester 《Journal of heterocyclic chemistry》1994,31(1):129-139
An efficient synthesis of the potent and orally active 5-HT1A agonists, (R)-(+)- and (S)-(-)-1-formyl-6,7,8,9-tetrahydro-N,N-dipropyl-3H-benz[e]indol-8-amines 1a and 1b , is described. This synthesis was accomplished in twelve steps from commercially available 1,5,6,7-tetrahydro-4H-indol-4-one ( 5 ). The key step involved a regio-controlled Friedel-Crafts acylation of 1-(p-toluenesulfonyl)indol-4-acetyl chloride with ethylene to yield a versatile synthon, 3-(p-toluenesulfonyl)-6,7,8,9-tetrahydro-3H-benz[e]indol-8-one ( 10 ). Subsequent coupling of this ketone with chiral α-methylbenzylamine under reductive amination conditions yielded a mixture of diastereomers. These diastereomers were efficiently separated by either chromatography or fractional recrystallization of the derived hydrochloride salts. Debenzylation of the pure diastereomers was followed by alkylation and formylation to yield (R)-(+)- and (S)-(-)-enantiomers 1a and 1b with >99% purity. 相似文献
75.
V. Barger A. D. Martin R. J. N. Phillips 《Zeitschrift fur Physik C Particles and Fields》1983,21(1):99-101
We point out properties of the “perpendicularev mass”, defined in terms of transverse momentap t byM T 2 (ev)=2|p eT | |p vT |?2p eT ·p vT , that make it particularly well suited toW mass and width determinations. We give an analytic expression for its distribution inW production and subsequentW→ev decay a \(\bar pp\) colliders, accurate to order 〈p WT 2 /M W 2 〉≈1%. A maximum likelihood fit of this formula to the five UA1 events givesM W=80.3 ?3 +6 GeV. 相似文献
76.
The design and operation of an automatic controlled-potential coulometer is described. It was primarily designed for use with mg quantities of uranium, neptunium and plutonium but can in principle be used on any element possessing more than one valency state in solution. It is capable of an accuracy and precision of ±0.25% and can analyse up to 20 samples on a set programme without operator attention. 相似文献
77.
Koontz JL Phillips KM Wunderlich KM Exler J Holden JM Gebhardt SE Haytowitz DB 《Journal of AOAC International》2005,88(3):805-813
Analysis of total folate concentration measured by microbiological assay in a variety of foods submitted in a routine manner to experienced laboratories that regularly perform folate analysis on fee-for-service basis was evaluated. Homogenates of fresh strawberries, frozen spinach, orange juice, frozen meat and vegetable pizza, dry macaroni, and dried pinto beans were prepared and stored under conditions previously determined to maintain stability of folate content. An aliquot of each composite and of 3 certified reference materials were sent on each of 4 occasions to 4 laboratories. Results for macaroni and pizza, the only folic acid-fortified foods, had considerably lower between-laboratory variation (CV(B)) with CV(B) of 9-11% versus >45% for other foods. Mean total folate ranged from 14 to 279 microg/100 g for a mixed vegetable reference material, from 5 to 70 microg/100 g for strawberries, and from 28 to 81 microg/100 g for wholemeal flour. Only 1 laboratory reported using a tri-enzyme extraction, and all laboratories used folic acid fortified foods as internal control materials. Users of commercial total folate analysis should understand the uncertainty in values determined by microbiological assay, particularly for foods containing primarily naturally occurring folate, which may not be apparent when replicate samples are not submitted for analysis. 相似文献
78.
The temperature dependence of phosphorescence of model enone compounds in poly (methyl methacrylate) matrix and glassy methylcyclohexane/isopentane solution and of enones formed from thermal oxidation of poly (butadiene) has been studied over the temperature range 77–220°K. The single discontinuity in the plot for the model enone-glassy solvent is due to the freezing of a (solvent perturbed) barrier to rotation in the enone, and an analogous transition is also observed in the model enone poly (methyl methacrylate) samples and in thermally oxidised poly (butadiene). In the polymer matrices, a second transition corresponding to the γ-transition in poly (methyl methacrylate) and the glass transition temperature Tg in poly (butadiene) are also revealed in the Arrhenius plots. The results demonstrate that care must be taken in ascribing such discontinuities solely to polymer properties since intrinsic properties of the luminescence probe itself may exhibit similar features. 相似文献
79.
The preparations, stabilities and structures of the complexes R2TlX and R2 LTlX (R = C6F5, p-HC6F4, or o-HC6F4; X = Br or Cl; L = Ph3PO, 2,2′-bipyridyl (bpy) or Ph3P) have been examined or (R = C6 F5) reinvestigated. The derivatives R2TlX are monomeric in acetone, from which the complex (p-HC6F4)2 Me2COTIBr has been isolated. In this solvent, the complexes R2LTlX (L = Ph3PO, bpy, or Ph3P) undergo partial dissociation by loss of L. When L = bpy, there is also slight ionization into R2LTl+ and R2TlX?2. The acceptor properties of R2TlX compounds towards uncharged ligands decrease R = C6F5 ? p-HC6F4 > o-HC6F4 > Ph. Dimeric behaviour is observed for R2TIX compounds in benzene, whilst R2LTlX (L = Ph3PO or bpy) derivatives show slight but significant association. In the solid state, R2TlX compounds are considered to be polymeric with five coordinate thallium, and R2LTlX derivatives to be dimeric with five (L = Ph3PO) or six (L = bpy) coordinate thallium by contrast with four coordinate dimeric and four or five coordinate monomeric structures previously proposed for the respective pentafluorophenyl derivatives. Halogen bridging is unsymmetrical for R = C6F5 or p-HC6F4, but may be more symmetrical for R = o-HC6F4 when L = Ph3PO or bpy. Reported structural data for the complexes (C6F5)LTlX (L = Ph3AsO, Ph3P, Ph3As, or 1,10-phenanthroline; X = Br or Cl) and (C6F5)2TlCl?2 are reinterpreted and the proposed structures revised. 相似文献
80.
Kim Henrick Mary McPartlin Glen B. Deacon Roderic J. Phillips 《Journal of organometallic chemistry》1980,204(3):287-294
An X-ray crystallographic study has shown that the complex (C6H5)2TlO2CC6F5(OPPh3) has a dimeric structure with unsymmetrical pentafluorobenzoate bridging (TlO 2.531 and 2.789 Å) but an exact crystallographic centre of symmetry. The pentafluorobenzoate groups are also unsymmetrically chelated to thallium (TlO 2.389 and 2.531 Å.), which overall has irregular six coordination. 相似文献