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161.
Blue BE Weber SV Glendinning SG Lanier NE Woods DT Bono MJ Dixit SN Haynam CA Holder JP Kalantar DH Macgowan BJ Nikitin AJ Rekow VV Van Wonterghem BM Moses EI Stry PE Wilde BH Hsing WW Robey HF 《Physical review letters》2005,94(9):095005
The first hydrodynamic experiments were performed on the National Ignition Facility. A supersonic jet was formed via the interaction of a laser driven shock ( approximately 40 Mbar) with 2D and 3D density perturbations. The temporal evolution of the jet's spatial scales and ejected mass were measured with point-projection x-ray radiography. Measurements of the large-scale features and mass are in good agreement with 2D and 3D numerical simulations. These experiments provide quantitative data on the evolution of 3D supersonic jets and provide insight into their 3D behavior. 相似文献
162.
163.
The chloro bridges in di-μ-chloro-4-methoxy- and di-μ-chloro-4-acetoxy-2-methyl-but-2-enylchloropalladium are split by Group V donor ligands Ph3E (where E = P, As and Sb) to give [(η)3-H2CC(CH3)CHCH2X) PdCl · EPh3], (where X = OCH3, OCOCH3). These complexes are readily decomposed by dilute ethanolic hydrogen chloride yielding [Ph3E · PdCl]2 and isoprene. The structures of the compounds are discussed in the light of their 1H NMR spectra. 相似文献
164.
A three-phase simulation written in Pascal and using a suite of procedures developed by Lancaster University and the London School of Economics is developed to model a group of ships subject to submarine and air attacks during an extended period of conflict. The simulation collects statistics on weapon usage by the ship group in order to study the impact of attrition, including the effects of preferential targeting, and correlation between the usages of different weapon systems, on war arsenal requirements. 相似文献
165.
The PT behavior of the carbon dioxide/normal alkane series exhibits a distinct transition in the CO2/nC13H28 system. This particular diagram is characterized by two liquid—liquid—vapor (l-l-g) loci, a lower liquid-upper liquid (l-l) critical branch extending from high pressures to the upper critical end point (UCEP) and two liquid—vapor (l-g) critical branches which cross near the lower critical end point (LCEP).An experimental PTx diagram in the vicinity of the CO2 critical point, LCEP and K point reveals the emergene at the LCEP of a l-l region which increases in size with temperture while the upper liquid—vapor (L2-g) region diminishes, eventually disappearing at the K point. The l-l-g surface illustrates the compositional changes of each phase with temperture.Detailed Px diagrams at three temperatures between the LCEP and K point are presented and each exhibits two critical points, a l-l-g locus and curves of constant phase volume ratio which show discrete changes in both value and slope at the l-l-g locus. Graphical and numerical methods of determining the phase densities and compositions from three phase volumetric behavior are presented. 相似文献
166.
Walter A. Korfmacher Claude L. Holder James P. Freeman Ronald K. Mitchum Aubrey B. Gosnell 《Journal of mass spectrometry : JMS》1985,20(7):435-439
The chemical ionization mass spectrometric (CIMS) analysis of doxylamine, N,N-dimethyl-2-[1-phenyl-1-(2-pyridinyl)ethoxy]ethanamine, and related compounds, using both ammonia and methane as reagent gases, is discussed. The two reagent gases did not produce the same major fragment ion for doxylamine. Mechanisms for the fragmentation of doxylamine under either ammonia or methane CIMS conditions are proposed. The mechanisms explain the observation of an m/z 182 fragment ion for doxylamine analyzed under methane CIMS conditions and an m/z 184 product ion detected under ammonia CIMS conditions. 相似文献
167.
168.
Brewis M Clarkson GJ Helliwell M Holder AM McKeown NB 《Chemistry (Weinheim an der Bergstrasse, Germany)》2000,6(24):4630-4636
The synthesis, structural characterisation and properties of a number of phthalocyanine-containing dendrimers are described. Peripheral substitution of phthalocyanine (Pc) with four poly(aryl ether) dendritic wedges (1st, 2nd or 3rd generation) produces materials whose properties are dominated both by the columnar self-association of the Pc core and by the glass-forming character of the dendritic substituents. Asymmetric Pcs containing a single poly(aryl ether) dendron display a columnar mesophase, the structure of which can be frozen into an anisotropic glass at room temperature. Placing the dendritic wedges at the axial sites of silicon phthalocyanine prohibits self-association and gives materials from which can be fabricated robust, isotropic solid solutions of Pc with high glass transition temperatures. A single crystal X-ray diffraction analysis of one of these compounds illustrates the ability of the axial dendrons to prevent cofacial aggregation in the solid state. 相似文献
169.
Evans RL Rushing LG Billedeau SM Holder CL Siitonen PH 《Journal of chromatographic science》2005,43(2):76-80
Ethinyl estradiol (EE2) is an extremely potent synthetic estrogen and a common component in oral contraceptives. The drug has a well-characterized pharmacological profile and is used as a positive control in toxicological investigations of compounds having estrogenic activity. An analytical method developed for the determination of low microg/kg levels of EE2 in a casein-based rodent diet is presented. A methanol extract of casein diet is purified for instrumental analysis by a 3-fold solid-phase extraction process. The sample extract is derivatized with pentafluoropropionic anhydride to the pentafluoropropionyl product and analyzed by capillary gas chromatography with electron-capture detection. Recoveries of EE2 from casein diet fortified at 5, 10, and 50 microg/kg average 88.8% and have a relative standard deviation (%) of 7.2. The method limit of detection in a casein-based diet is 1 microg/kg. 相似文献
170.
Kim MJ Konduri R Ye H MacDonnell FM Puntoriero F Serroni S Campagna S Holder T Kinsel G Rajeshwar K 《Inorganic chemistry》2002,41(9):2471-2476
Two new ruthenium(II) polypyridyl dimers containing the large planar aromatic bridging ligands 9,11,20,22-tetraazatetrapyrido[3,2-a:2'3'-c:3' ',2'-l:2',3'-n]pentacene (tatpp) and 9,11,20,22-tetraazatetrapyrido[3,2-a:2'3'-c:3',2' '-l:2',3'-n]pentacene-10,21-quinone (tatpq) have been synthesized and characterized by (1)H and (13)C NMR, MALDI mass spectrometry, and elemental analyses. The electronic properties (UV-vis, redox, photophysical) of these dimers are analyzed in the context of orbital calculations (PM3 level) on the bridging ligands. A localized orbital model is proposed in which low-lying acceptor orbitals on the center portion of the ligands effectively quench the Ru(II)-based MLCT emission via a mechanism that can be viewed as intramolecular electron transfer to specific subunits of the bridges. 相似文献