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21.
Three types of single-chain hydrocarbon fluorocarbon hybrid bolaamphiphiles were synthesized.They readily formed different kinds of organized supramolecular assemblies,including vesicles,tapes,and micellar fibers,in aqueous solution.The aggregates morphology was characterized by transmission electron microscopy (TEM) after negative staining.The superstructures of these aggregates seemed to be determined by the geometry and the head group's properties of the corresponding amphiphiles.  相似文献   
22.
Introduction0ncofthcintriguingpr0blcmsinhctcrogcncouscatal}'sisisthcactit'ationanddircctconversionofmcthancintoliquidfucIanduscful.h..i..l,lllMcthancactivationisvcry'difficultbccauscn1cthancisathcrmod}'namicalI}'stablccompoundt`ithanoblcgas-likcconfigurati0nThcvcry'strongtctrahcdralC-Hbonds(435kJ/mol)offcrnofiJnctionalgroups,magncticm0mcnts'orpolardistortionstofacilitatcchcmicalattackThismakcsmcthanelcssrcactivcthanncarl}'allitsconvcrsionproducts.Rccentl}'oxidativccouplinghasbecnconsidcrcda…  相似文献   
23.
4-tert-Butyl-2-cyclohexen-1-one dimerizes in THF solution via its kinetic enolate, leading to di-tert-butylditwistane 8 in up to 36% yield (−78 °C → room temp., protonolysis, flash chromatography). X-ray crystallography shows that 8 incorporates one R and one S enantiomer of the starting ketone; none of the diastereomeric ditwistanes epi-8, epi’-8 or iso-8 was isolated. This means that the formation of 8 proceeds with mutual kinetic resolution and 100% induced diastereoselectivity.  相似文献   
24.
本文研究了氢硼酸根(B_(12)H_(12)~(2-)、B_(10)H_(10)~(1-)、B_(11)H_(14)~-)和π-芳烃-π-环戊二烯基铁阳离子的反应,合成了36个氢硼酸π-芳烃-π-环戊二烯基铁化合物。通过元素分析和红外光谱测定确定了化合物的组成。部份化合物还作了~1H NMR鉴定。对化合物的性质,包括它们的热行为,进行了较详细的研究。DTA仪测得的结果表明,(1)当阳离子相同时,化合物的热稳定性的顺序为:[ArFeC_5H_5]_2B_(12)H_(12)>[ArFeC_5H_5]_2B_(10)H_(10)>[ArFeC_5H_5]B_(11)H_(14);(2)当氢硼酸根相同时,其热稳定性受芳环上取代基的影响。  相似文献   
25.
The speed of sound u in and densities of eight binary mixtures of p-dioxane (p-C4H8O2) with methylcyclohexane (c-C6H11CH3), 1-chlorohexane (C6H13C1), 1-bromohexane (C6H13Br), p-xylene [C6H4(CH3)2], propylbenzene (C6H5C3H7), methyl acetate CH3COOCH3), butyl acetate (CH3COOC4H9), and amyl acetate (CH3COOC5H11) were measured over the whole composition range at 30°C. Isentropic compressibilities (K S), Rao's molar sound functions (R), excess molar volumes (V E), excess isentropic compressibilities (K S E ) together with relative change in volume V/12 values, have been obtained for all measured mole fractions. The excess partial molar volume (V1-V 1 0 ) of p-dioxane in different solvents have also been estimated. The experimental results have been analyzed in terms of the Prigogine–Flory–Patterson theory of solutions.  相似文献   
26.
Liquid or dense supercritical ammonia has been suggested as an extraction fluid. It is indeed good solvent for very different classes of compounds, as can be seen from phase diagrams. Such diagrams for binary systems of ammonia and hydrocarbons are presented and discussed on the basis of their critical curves. Apparatus and methods for the measurement of phase equilibria and equation of state data of fluid mixtures at high pressure are described.  相似文献   
27.
The usual methods for determining polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF) and polychlorinated biphenyls (PCB) are generally expensive and time consuming. This fact has favored the development of faster and cheaper techniques, based on immunoassays and bioassays. This paper reviews these bioanalytical methods and their analytical importance at the present moment.  相似文献   
28.
吸热型烃类燃料是一种热安定性好、可以利用其化学热沉的燃料,其热沉能够满足高超音速飞行的需要。本文论述了燃料热安定性、催化脱氢、催化裂解、引发裂解、超临界裂解等对吸热型烃类燃料热沉的影响,重点论述了引发裂解在吸热型烃类燃料中的裂解优势,提出引发裂解在高超音速飞行器上具有诱人的应用前景。  相似文献   
29.
This review summarizes the author’s contributions to the field of chemistry of group 10 metal complexes containing unsaturated hydrocarbon ligands, with a brief introduction showing how his research subject has shifted from mononuclear type to multinuclear type complexes. New structure and reactivity trends in the multipalladium complexes with bridging allyl and allenyl/propargyl ligands, as well as bridging conjugated polyene molecules are discussed in terms of some unique bonding features of these complexes.  相似文献   
30.
The application of coherent anti-Stokes Raman spectroscopy (CARS) to an electric are test reactor is described in which acetylene synthesis in analogy to the large-scale industrial process is .studied. We report on spatially resolved measurements of H2-CARS spectra, the comparison with calculated spectra, and the determination of temperatures in the reaction zone.Dedicated to Prof. Rudolf Wienecke on the occasion of his 65 birthday.  相似文献   
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