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31.
32.
J. Engels J. Fingberg K. Redlich H. Satz M. Weber 《Zeitschrift fur Physik C Particles and Fields》1989,42(2):341-347
InSU(2) lattice gauge theory, we study deviations from ideal gas behaviour near the deconfinement point. On lattices of sizeN σ 3 ×4,N σ=8, 12, 18 and 26, we calculate the quantityΔ≡(ε?3P)/T 4. It increases sharply just aboveT c , peaks atT/T c =1.15 ±0.05 and then drops quickly. This form of behaviour is shown to be the consequence of a second order phase transition. Dynamically it could arise because just aboveT c , the low momentum states of the system are remnant massive modes rather than deconfined massless gluons. 相似文献
33.
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M. Weber N. Trautmann H. Menke G. Herrmann und N. Kaffrell 《Fresenius' Journal of Analytical Chemistry》1973,267(3):192
Ohne ZusammenfassungDie ausführliche Veröffentlichung erfolgt in Radiochimica Acta [3]. 相似文献
35.
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Edwin Weber Claus Wimmer Ingeborg Csöregh Olga Gallardo 《Journal of inclusion phenomena and macrocyclic chemistry》1997,27(2):141-153
A novel host molecule, 1, suitable for crystalline lattice-type inclusion, has been synthesized, and its cocrystal formation ability has been investigated. Host 1 proved to be of potential use for organic solvent separation and retrieval, and a promising auxiliary for solidification of certain odorous substances. The crystal structures of the solvent-free host 1, and its complex with 1,4-dioxane (1 : 1), have been determined by single crystal X-ray diffraction. The structure of 1 (guest-free) is triclinic, P
, with a = 9.452(2), b = 10.359(3), c = 13.116(3) Å, = 101.80(2), = 106.53(1) and = 104.32(1)°. The spacious, propeller-like molecules are held together by weak van der Waals' forces. The dioxane inclusion compound is monoclinic, P21/a, with a = 15.050(1), b = 8.641(1) and c = 20.658(1) Å, and = 94.56(1)°, and contains two crystallographically independent guest molecules, both located around symmetry centres. The molecular packing seems to be governed by C—H···O type bonds (C···O = 3.31 and 3.48 Å) from the host to the dioxane oxygens. 相似文献
37.
The crystal structure of 12,13-dibromopseurotin has been determined by single crystal X-ray analysis. The crystals belong to space group P21 with a = 16.75, b = 9.63, c = 7.42 Å, β 95.9°, Z = 2. The structure was solved by the heavy atom technique and refined to R = 0.062 with 819 significant reflexions for 299 parameters. 相似文献
38.
Cynthia M. Allen Joseph M. Weber Johan E. van Lier 《Photochemistry and photobiology》1995,62(1):184-189
Abstract— Transmission of infectious diseases through blood transfusions is well known. Ultraviolet irradiation, solvents and detergents provide a means of sterilizing noncellular blood components. However these harsh methods are not applicable to cellular blood products. Recently, attempts have been made to sterilize biological fluids using photodynamic treatment and phthalocyanine (Pc) dyes have been advanced as photosensitizers for this purpose. We have evaluated a series of water-soluble Pc, chelated with different central metal ions, substituted to different degrees with sulfonato and r-butyl groups, for their effectiveness to reduce virus infectivity in red blood cell suspensions. Vaccinia virus cytopathogenicity was determined by endpoint serial dilutions in the CV-1 cell line. Anti-viral activity increased with the central metal ion in the following order: Ga(III) < Al(III) < Zn(II), and varied inversely with the degree of sulfonation. Furthermore, addition of a t -butyl group onto the trisulfonated dyes (PcS3 [ t -Bul) resulted in a 5–40-fold increase in anti-viral potency, suggesting that amphiphilicity enhances the photodynamic activity of the dye. Strong anti-viral photosensitizing properties cannot be the sole selection criterion. Of equal importance is the preservation of blood component integrity. Accordingly, the photohemolytic activity of the dyes was evaluated using the rate of hemolysis as a parameter and a toxicity index was defined. Among the most active dyes, the AlPcS3 ( t -Bu) complex exhibited the most favorable anti-viral properties combined with a low toxicity index. Our results suggest that trisulfophthalocyanines, bearing an additional t -butyl group to enhance amphiphilicity, are particularly promising dyes for photodynamic blood sterilization. 相似文献
39.
40.
Sensitive determination of free and plasma protein-bound dipyridamole by high-performance liquid chromatography 总被引:1,自引:0,他引:1
For many years dipyridamole (DP) has been used in the treatment of hypertension as a vasodilator, but recently it has been recognised as an anti-platelet aggregation agent and to potentiate anti-metabolite activity. A rapid and sensitive (20 nM) procedure for the determination of free and protein-bound DP in plasma, using reversed-phase high-performance liquid chromatography on an Ultrasphere XL ODS (3 microns) column (70 mm x 4.6 mm I.D.) with ultraviolet detection (280 nm), is reported. Free and bound DP were separated using ultrafiltration. Concentrations of DP between 0.1 and 10 microM were measured in plasma with a relative standard deviation of less than 9.6%. The subsequent determination of DP levels in patients orally administered 450 mg per day showed that DP binding to plasma protein is higher than 90%. 相似文献