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81.
A novel antibacterial coating for cotton and polyester fabrics has been developed by using drug-loaded proteinaceous microspheres made of bovine serum albumin and casein proteins. The microbubbles were created and anchored onto the fabrics (see figure) in a one-step reaction that lasts 3 min. The sonochemically produced "antibacterial fabrics" have been characterized. The efficiency of the sonochemical process in converting the native proteins into microspheres, encapsulating the drug, and coating the fabric has also been studied.  相似文献   
82.
Abstract—The use of photoacoustic spectroscopy in the study of photoactive samples (photochemical, luminescent, photovoltaic) is considered. After a short explanation of the parameters important in this technique and ways of measuring them, photochemical processes are considered in detail. Relations are derived for the determination of the energy stored in photochemical products and the quantum yield for the photochemical processes.
One- and two-step photochemical processes are treated in detail and the dependence of the photo-acoustically detected products on modulation frequency is considered, showing the possibility of separating reaction steps according to their rate constants. Particular attention is given to the photosynthetic process and the potential of this method for determination of energy conversion efficiencies of the different stages of photosynthesis is demonstrated. Also the use of the technique in the study of photovoltaic processes is outlined.  相似文献   
83.
We develop some new tools for the study of minimal transformation groups (flows) and apply these tools to extend the classification theory of minimal flows to a larger class than has previously been classified. The tools we develop arise from a simplification and unification of the techniques used by Furstenberg, Ellis, and Veech in their proofs of structure theorems about distal and point distal flows. This simplification is made possible largely through the use of recent results of Glasner on the structure of 2X (whose points consist of closed subsets of the phase space X of a given flow).  相似文献   
84.
We exhibit a general class of interactive decision situations in which all the agents benefit from more information. This class includes as a special case the classical comparison of statistical experiments à la Blackwell. AMS 2000 Subject Classification:Primary 91A35.The work of Bruno Bassan and Marco Scarsini was partially supported by MIUR-COFIN. The authors express their thanks to Sylvain Sorin for enlightening comments.  相似文献   
85.
    
In this paper we address the existence of smooth manifolds proper homotopy equivalent to nonuniform arithmetic manifolds M = ΓG/K that are not homeomorphic to it. While the manifolds M are properly rigid if rank(Γ) ≤ 2, we show that the so‐called virtual structure group has infinite rank as a ℚ‐vector space if rank(Γ) ≥ 4.© 2015 Wiley Periodicals, Inc.  相似文献   
86.
The formation and properties of Cs inclusions in Mo and W are observed through a preimplanted133Xe(Cs) local probe, which is found to reside in three sites: a substitutional site, an interfacial one and a further site which is not detectable directly, but the presence of which can be inferred from the Mössbauer measurements. The location of the probe at the interface of small Cs inclusions is characterized by large Debye temperatures of around 200 K, a quadrupole interaction of +1.86(15) mms–1, which is close to known surface site values, and an isomer shift of –0.33(12) mms–1. From the latter value an approximate local pressure of 5 GPa is deduced. In W the site populations are followed as a function of Cs dose. The observed interchange of populations in the low dose range is thought to represent the initial formation of the second phase inclusions.  相似文献   
87.
The title diketone has been prepared by a synthetic sequence beginning with decane-1,10-dicarboxylic acid.  相似文献   
88.
89.
The conditions required for a formal biradical to exist in a zwitterionic form in the ground state are discussed following the recent experimental observation of zwitterionic structure in the ground state of a quinoid molecule (di-tert-butyl derivative of 2,5-diamino-1,4-benzoquinonediimine, I). A unique characteristic of molecules of this class is the fact that they may be considered as being formed by the union of two radicals, each having an odd number of pi electrons. In the case of I, one fragment carries the two amino group having 7 pi electrons; it acts as the electron donor. The other fragment carries the two oxygen atoms (carrying 5 pi electrons) and acts as an electron acceptor. A model that predicts the properties of these systems is presented, based on previous work on non-Kekule hydrocarbons(2,3) and on the electron donating and attracting properties of the donor and acceptor groups, respectively. The zwitterion is formed by an electron transfer leading to two subunits carrying 6 pi electrons each and may become more stable than the triplet biradical even in the gas phase (i.e., in the absence of an external field) if the ionization potential of the donor is small (of the order of 3-4 eV). In some cases solvation in a polar solvent is required to make the zwitterionic form the lowest energy species on the ground-state surface. The 'spacer' between the donor and acceptor groups (which need not be necessarily derived from an aromatic structure) can be varied and influences the overall dipole moment that is calculated in some cases to be quite large (over 20 D in the gas phase).  相似文献   
90.
Retro Diels Alder fragmentation is highly stereospecific in the diones 1 under chemical ionization conditions, both with methane and isobutane as the reagent gases. Only the cis-isomers yield abundant protonated diene and quinone ions. The isotope effect indicates preferential protonation on a CO oxygen, and a subsequent H-migration prior to the formation of the protonated diene cations in the cis isomers.  相似文献   
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