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81.
Thomas Merakis Annette Murphy Leone Spiccia Alan Beguin Werner Marty 《Helvetica chimica acta》1989,72(5):993-995
Crystalline salts of the hydrolytic dimer of Cr(III), [Cr2(μ-OH)2(H2O)8]X4·n H2O (X = p-toluenesulfonate (tos) or mesitylene-2-sulfonate (dmtos)) have been prepared in good yields via a simple two-step procedure: H+ oxidation of Cr metal to give Cr2+ (T ≈? 70°) followed by O2 oxidation, of Cr2+ to give the dimer (T ≈? 25°). The mechanism of conversion of Cr2+ into the dimer is discussed. 相似文献
82.
Brian Murphy Peter Mcloughlin 《International journal of environmental analytical chemistry》2013,93(7-8):653-662
The potential of an optical sensor based on mid-infrared spectroscopy, utilising a zinc selenide (ZnSe) attenuated total reflectance (ATR) element coated with an amorphous Teflon polymer, to determine chlorinated hydrocarbon species (CHC) in an aqueous environment is examined. The polymer coating concentrates the analytes within the penetration depth of the Fourier transform infrared (FTIR) evanescent wave and excludes water from the region. Teflon AF (Amorphous Fluoropolymer) is a family of amorphous copolymers based on polytetrafluoroethylene (PTFE), and is commercially available in two polymeric grades. Teflon AF is highly amorphous in nature with a large 'void volume', exhibits excellent chemical resistance and low water absorption. Such properties identify it as an excellent candidate for enrichment coating on an ATR/FTIR sensor. The potential of both polymeric grades of Teflon AF as enrichment membranes for ATR/FTIR analysis of CHC species was examined and contrasted. A rapid, repeatable, reversible response was observed with both grades to a range of CHC species. Linear responses in the mg/L region, with detection limits in the low mg/L region were achieved with the system used. 相似文献
83.
84.
An ultra-high speed, time-resolved particle image velocimetry (PIV) system is developed to measure velocity fields created
by explosive detonators. When initiated into a gas, the detonators generate blast waves that propagate outwards from the origin
of initiation at supersonic speeds. The PIV system consists of a custom eight-pulse Nd:YAG laser system and an ultra-high
speed camera system comprising four dual-frame CCD cameras optically combined to share a single optic axis. The system is
capable of sampling the flow field four times at up to 333 MHz or eight times at up to 8 MHz. System development is discussed,
and preliminary application to the complex flow behind the blast wave from an exploding bridge wire detonator is demonstrated. 相似文献
85.
Bromoalkynol derivatives of diacetone glucose undergo rearrangements to dihaloenol ethers contained in furo[3,4-b]furan cores when treated with halonium-producing reagents. [reaction: see text] 相似文献
86.
Kuehn K Mehta S Fu H Genio E Murphy D Liu F Liu Y Ahlers G 《Physical review letters》2002,88(9):095702
We report new measurements in four cells of the thermal boundary resistance R between copper and (4)He below but near the superfluid-transition temperature T(lambda). For 10(-7)< or =t identical to 1-T/T(lambda))< or =10(-4) fits of R = R(0)t(-x(b))+R(B) to the data yielded x(b) approximately equal to 0.18, whereas a fit to theoretical values based on the renormalization-group theory yielded x(b) = 0.23. Alternatively, a good fit of the theory to the data could be obtained if the amplitude of the prediction was reduced by a factor close to 2. The results raise the question whether the boundary conditions used in the theory should be modified. 相似文献
87.
The preparation and physical properties of the layered VS2, MyV1?yS2 (M = Fe or Cr), and their lithium intercalation adducts are described. These compounds were prepared by oxidative delithiation of LiMyV1?yS2 with iodine. Crystallographic distortions present in LixVS2 (0.25 ? x ? 0.6) are suppressed by Fe or Cr substitution for V. The electrochemical sluggishness of Li/Li+/VS2 cells is reduced by the substitution. 相似文献
88.
Activated aryl aroylcyclopropanes cyclise with Lewis acids under mild conditions to 1-aryltetralones. 相似文献
89.
H. V. Murphy 《The Journal of the Operational Research Society》1969,20(1):59-79
Quantitative methods are derived to assist buyers purchasing commodities in fluctuating price markets. Demand is known whilst price is a stochastic variable which may contain trends or seasonal fluctuations. The essential feature of the problem is that the buyer has many opportunities to make a purchase.Mathematical models are formulated to describe particular commodity buying problems. The optimal purchasing policy is derived by using dynamic programming. It consists of a set of discrete price breaks at each buying opportunity together with the associated stock levels the buyer should aim to achieve at each price break with his purchase at this opportunity. The price breaks are dependent on the probability density functions of future prices and the number of future buying opportunities. Recurrence relations are derived to calculate these price breaks. The case of restrictions on the purchase quantity at each price offer, either because of supply limitations or by the buyer as a policy decision, and price discounts are also considered.A case study illustrating the techniques is given and the methods are extended to purchasing for a blending problem with substitutable commodities. 相似文献
90.
A new stable product from the reaction of nitrosobenzene and N-ethoxycarbonylazepine is shown to be a 1,4-cycloadduct. 相似文献