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51.
We investigated the deformation of a strong shear thinning droplet undergoing simple shear flow in a Newtonian liquid. The
droplet was an aqueous solution of poly(ethylene oxide) end capped with an alkyl group that forms spherical micelles in aqueous
solution. At high concentrations and below a critical temperature, the jammed micelles showed strong shear thinning behaviour,
and neither a yield stress nor a Newtonian viscosity was observed. At small shear rates, the droplet rotated and aligned in
the flow, but did not deform or only very weakly. At high shear rates, the droplet deformation increased with increasing shear
rate. The deformed droplet did not relax after the shear was stopped except for a modest rounding of the edges. For each shear
rate, an apparent viscosity, η
ad, of the equivalent Newtonian droplet was calculated assuming affine deformation. η
ad showed a power law dependence on the capillary number Ca with an exponent of − 1.8 and was larger than the shear viscosity
of the micelle suspension at the same shear rates. The results were explained by the existence of a strong gradient of the
viscosity inside the droplet leading to a very low viscosity fluid layer near the droplet/matrix interface. 相似文献
52.
53.
Mabrouk Majdi Marchand Mickael Russello Aldo Baronnet Jean Marie Lemont Florent 《Plasma Chemistry and Plasma Processing》2015,35(1):45-60
Plasma Chemistry and Plasma Processing - A process for the destruction of organic liquid waste has been developed in which a nontransferred arc plasma torch is operated with oxygen as the plasma... 相似文献
54.
Hans R. Kricheldorf Majdi Al-Masri 《Journal of polymer science. Part A, Polymer chemistry》1996,34(10):2037-2043
4,4′-Bistrimethylsiloxy diphenylsulfone was polycondensed with six different alkylating agents in N-Methylpyrrolidone/K2CO3 mixtures and polyethers were isolated from all experiments. The best results were obtained with the mesylate of bis(2-hydroxyethyl)hydroquinone, BHEH. Similar results were found when silylated n-butyl-3,5-dihydroxybenzoate was used. A comparison of five different reaction media revealed that NMP gives the highest molecular weights. Finally, various silylated diphenols containing functional groups were polycondensed with the mesylate of BHEH. In this way polyethers with pending ester, aldehyde, keto, and amide groups were obtained. © 1996 John Wiley & Sons, Inc. 相似文献
55.
Abstract
Genetic effects of UV-A, UV-B, UV-C, and the combination of 8-methoxypsoralen (8MOP) with UV-A or visible light were studied in the haploid strain XV185–14C and diploid strain D5 of Saccharomyces cerevisiae. The induction of his+, lys+, and horn+ reverse mutations was measured in strain XV185–14C. In strain D5 we measured the induction of genetically altered colonies, particularly twin spot colonies arising from a mitotic crossing-over. UV-C and UV-B induced point mutations at the three loci in the haploid strain and mitotic crossing-over and other genetic alterations in the diploid strain. UV-C was more mutagenic and recombinogenic than UV-B. UV-A or visible light alone did not induce genotoxic effects at the doses tested. However, UV-A plus 8-MOP produced lethal and mutagenic effects in the haploid strain XV185–14C, although mutagenic activity was less than that of UV-B. Visible light plus 8-MOP also induced genotoxic effects in strain XV185–14C. In the diploid strain D5, UV-A plus 8-MOP induced a higher frequency of genetic alterations than UV-B at comparative doses. Visible light plus 8-MOP was also genetically active in strain D5. The haploid strain was more sensitive to the lethal effects of UV-C, UV-B, UV-A, and impure visible light plus 8-MOP than the diploid strain. 相似文献
Genetic effects of UV-A, UV-B, UV-C, and the combination of 8-methoxypsoralen (8MOP) with UV-A or visible light were studied in the haploid strain XV185–14C and diploid strain D5 of Saccharomyces cerevisiae. The induction of his+, lys+, and horn+ reverse mutations was measured in strain XV185–14C. In strain D5 we measured the induction of genetically altered colonies, particularly twin spot colonies arising from a mitotic crossing-over. UV-C and UV-B induced point mutations at the three loci in the haploid strain and mitotic crossing-over and other genetic alterations in the diploid strain. UV-C was more mutagenic and recombinogenic than UV-B. UV-A or visible light alone did not induce genotoxic effects at the doses tested. However, UV-A plus 8-MOP produced lethal and mutagenic effects in the haploid strain XV185–14C, although mutagenic activity was less than that of UV-B. Visible light plus 8-MOP also induced genotoxic effects in strain XV185–14C. In the diploid strain D5, UV-A plus 8-MOP induced a higher frequency of genetic alterations than UV-B at comparative doses. Visible light plus 8-MOP was also genetically active in strain D5. The haploid strain was more sensitive to the lethal effects of UV-C, UV-B, UV-A, and impure visible light plus 8-MOP than the diploid strain. 相似文献
56.
In this paper, we prove a combinatorial rule describing the restriction of any irreducible representation of U(n+m) to the subgroup U(n)×U(m). We also derive similar rules for the reductions from SU(n+m) to S(U(n)×U(m)), and from SU(n+m) to SU(n)×SU(m). As applications of these representation-theoretic results, we compute the spectra of the Bochner–Laplacian on powers of the determinant bundle over the complex Grassmannian . The spectrum of the Dirac operator acting on the spin Grassmannian is also partially computed. A further application is given by the determination of the spectrum of the Hodge–Laplacian acting on the space of smooth functions on the unit determinant bundle over . 相似文献
57.
Dimethyl terephthalate was reacted with 5,5′-Isopropylidene-bis(ethyl 2-furoate), 1,4:3,6-dianhydrohexitols and ethan-1,2-diol in order to obtain PET incorporating bio-based moieties. Polycondensation was achieved in two steps: (i) the formation of a hydroxyethyl-terminated oligomer by reaction of starting diester mixture with excess ED and, (ii) a polycondensation step with elimination of ED was used to obtain high molar mass copolyesters. Copolymers of various compositions were synthesized and characterized by 1H-NMR, SEC, DSC and TGA. The resulting materials are amorphous polymers (T g = 104–127 °C) with good thermal stability. 相似文献
58.
Using first-principle methods, we characterized Ar(m)BeO(q+) (0 ≤ m ≤ 3 and 0 ≤ q ≤ 2) and BeO(q+) (3 ≤ q ≤ 5) multicharged ions (MCIs). This includes their structural parameters, relative stabilities and vibrational wavenumbers. Our calculations confirm the existence of the ArBeO complex. In addition, we found (meta-)stable neutral and ionic complexes such as ArBeO(+), ArBeO(2+), Ar(2)BeO, Ar(2)BeO(+), Ar(2)BeO(2+), Ar(3)BeO, Ar(3)BeO(+) and Ar(3)BeO(2+). The analysis of the structural parameters and of the electron density differences shows that a strong perturbation in the electronic structure of the BeO(q+) (q = 1,2) moiety occurs upon complexation, resulting in a major increase in covalency of these multicharged ions (MCIs). The consequences of solvation of MCIs in argon matrices are pointed out. More generally, the effects on the spectroscopy of MCIs trapped on cold matrices are discussed. 相似文献