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21.
Polymer drugs are those in which a polymer agent has a direct therapeutic effect on the body. A major investigated area of polymer drugs is their use as binding agents, or sequestrants, which can neutralize or remove undesired components from the body. By taking advantage of the unique properties of crosslinked, insoluble polymers, new polymer drugs continue to be developed for oral use, acting in the gastrointestinal tract and excreted in the feces. Soluble polymer binders may be administered by a variety of routes and act at diverse sites of therapeutic action. This article reviews the properties of polymer drugs, particularly sequestrants, with an emphasis on recent advances in polymer properties which may enhance the utility of this class of drugs. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3146–3157  相似文献   
22.
Emission spectra of naphthalene, anthracene and naphthacene, oriented in stretched polyethylene sheets, have been studied. Absolute polarization of the bands and symmetry assignments of the vibrational modes are deduced and progressions of bands are drawn up. A comparison with other polarization investigation is given.To support the interpretation of the film spectra the molecules have also been measured (20 K) in suitable crystalline solvents (Shpolskú matries). Discrepancies with the literature are discussed. The anomalous behavior of the environment multiplet structure of naphthacene in n-nonane is described.  相似文献   
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24.
The antimicrobial properties of light is an area of increasing interest. This study investigates the sensitivity of the significant foodborne pathogen Listeria monocytogenes to selected wavelengths of visible light. Results demonstrate that exposure to wavelength region 400–450 nm, at sufficiently high dose levels (750 J cm?2), induced complete inactivation of a 5 log10 population. Exposure to wavelengths longer than 450 nm did not cause significant inactivation. Analysis of 10 nm bandwidths between 400 and 450 nm confirmed 405(±5) nm light to be most effective for the inactivation of L. monocytogenes, with a lesser bactericidal effect also evident at other wavelengths between 400 and 440 nm. Identification of the optimum bactericidal wavelength enabled the comparison of inactivation using 405(±5) nm filtered light and a 405 nm light‐emitting diode (LED) array (14 nm FWHM). Results demonstrate similar inactivation kinetics, indicating that the applied dose of 405 nm light is the important factor. Use of the 405 nm LED array for the inactivation of L. monocytogenes and other Listeria species resulted in similar kinetics, with up to 5 log10 reductions with a dose of 185 J cm?2. Comparative data for the 405 nm light inactivation of L. monocytogenes and other important foodborne pathogens, Escherichia coli, Salmonella enteritidis and Shigella sonnei, are also presented, with L. monocytogenes showing higher susceptibility to inactivation through 405 nm light exposure.  相似文献   
25.
The hypothiocyanate anion (OSCN)(-) is reported to be a major product of the lactoperoxidase/H(2)O(2)/(SCN)(-) system, and this anion is proposed to have significant antimicrobial properties. The collision induced (CID) negative ion mass spectrum of "(OSCN)(-)" has been reported: there is a pronounced parent anion at m/z 74, together with fragment anions at m/z 58 (SCN)(-) and 26 (CN)(-). These fragment anions are consistent with structure (OSCN)(-). However there is also a lesser peak at m/z 42 (OCN(-) or CNO(-)) in this spectrum which is either formed by rearrangement of (OSCN)(-) or from an isomer of this anion. The current theoretical investigation of (OSCN)(-) and related isomers, together with the study of possible rearrangements of these anions, indicates that ground-state singlet (OSCN)(-) is a stable species and that isomerization is unlikely. The three anions (OSCN)(-), (SCNO)(-), and (SNCO)(-) have been synthesized (in the ion source of a mass spectrometer) by unequivocal routes, and their structures have been confirmed by a consideration of their collision induced (negative ion) and charge reversal (positive ion) mass spectra. The CID mass spectrum of (SCNO)(-) shows formation of m/z 42 (CNO(-)), but the corresponding spectra of (OSCN)(-) or (SNCO)(-) lack peaks at m/z 42. Combined theoretical and experimental data support earlier evidence that the hypothiocyanite anion is a major oxidation product of the H(2)O(2)/(SCN)(-) system. However, the formation of m/z 42 in the reported CID spectrum of "(OSCN)(-)" does not originate from (OSCN)(-) but from another isomer, possibly (SCNO)(-).  相似文献   
26.
We will investigate the geometry of rational equivalence classes of points on a surface S. We will show that if S is a general projective K3 surface then these equivalence classes are dense in the complex topology. We will also show that if S has the property that these equivalence classes are Zariski dense, then h2,0(S)?1. To cite this article: C. Maclean, C. R. Acad. Sci. Paris, Ser. I 338 (2004).  相似文献   
27.
This paper reports on the first observations of a promising new form of optically triggered modal bistability in semiconductor lasers. The bistable mechanism involves a switch between the degenerate in-phase and antiphase coupled modes of an index-guided, twin-ridge laser operating at 1.3 μm wavelength. Experimental results have indicated sub-picojoule bistable switching with switching times of less than 250 ps. Possible limitations of device performance are discussed, with particular reference to asymmetry of the ridge structure.  相似文献   
28.
The addition of the surfactant SDS to an aqueous solution containing 1·2 results in the disassembly of the latter via the simultaneous incorporation of 1 into a micelle and the precipitation of 2 by an anion exchange reaction.  相似文献   
29.
A pyrazine bridged ruthenium/palladium bimetallic photocatalyst with peripheral 4,4'-dicarboxyethyl-2,2'-bipyridine ligands, EtOOC-RuPd, is reported, together with its 2,2'-bipyridine analogue. Upon irradiation with visible light, EtOOC-RuPd catalyses the production of hydrogen gas whereas the complex RuPd does not.  相似文献   
30.
Direct diode-laser pumping of a mode-locked Ti:Al(2)O(3) laser is reported. A single 1 W GaN-based diode laser operating at 452 nm is used as the pump laser. Pulse durations as short as 114 fs and average output powers of up to 13 mW are obtained.  相似文献   
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