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981.
Preparation and properties of textile materials modified with triclosan‐loaded polylactide microparticles 下载免费PDF全文
Agnieszka Karaszewska Irena Kamińska Magdalena Kiwała Mariusz Gadzinowski Mateusz Gosecki Stanislaw Slomkowski 《先进技术聚合物》2017,28(9):1185-1193
A convenient and simple method for preparation of commercial nonwovens with antimicrobial properties was elaborated. The process consists in preparation of poly(l ‐lactide) microspheres (from poly(l ‐lactide) with M n = 10,560 and M w /M n = 1.39) containing triclosan (5‐chloro‐2‐(2,4‐dichlorophenoxy) phenol) and loading them onto the nonwovens. The microspheres were prepared by spray drying (D n = 3.91 μm, D w /D n = 2.43) and oil‐in‐water emulsification‐solvent evaporation method (D n = 5.84 μm, D w /D n = 1.25). Content of triclosan in microspheres ranged from 4.65 to 4.95 wt%. The antibacterial nonwovens were prepared by padding of the fibers with the microspheres using the microsphere suspension. The resulting antibacterial nonwovens were examined using inhibition zone measurement method. Inhibition zones from 4 to 9 mm indicated that the modified nonwovens had antibacterial properties against Gram (+)—Staphylococcus aureus and Gram (?)—Klebsiella pneumoniae . Nonwovens were conditioned up to 12 months at relative humidity <5%, 50%, and 100% in desiccators and up to 6 months air‐conditioning system at relative humidity = 65%. Antimicrobial activity of the modified nonwovens was examined as a function of time and air humidity. Time of conditioning has strong influence on antibacterial activity, whereas the impact of the air humidity was negligible. All nonwovens had antibacterial properties even after 12 months of conditioning. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
982.
Ksenija Dumičić Anita Čeh Časni Irena Palić 《Central European Journal of Operations Research》2013,21(1):3-11
In this paper cointegration and error correction models are used to explore the long run and short run behavior of personal consumption in Croatia as a function of income, house prices and total credit to households. The results of the analysis showed that income (approximated by net real wage), house price and total credits to households play an important role in determining personal consumption. Also, lagged values of house prices showed significant impact on consumption, suggesting house price persistence. The most likely factors driving the house price persistence may include expectations and idiosyncratic institutional characteristics like illiquid real estate markets, inadequate property rights protection, high transaction costs, and underdeveloped financial instruments. 相似文献
983.
984.
Summary Let Abe a semisimple H*-algebra and let T: A→Abe an additive mapping such that T(x
n
+1)<span lang=EN-US style='font-size:10.0pt;mso-ansi-language:EN-US'>=T(x)x
n+x
n
T(x) holds for all x∈Aand some integer n≥1. In this case Tis a left and a right centralizer. 相似文献
985.
B. Amaziane M. Goncharenko L. Pankratov 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2007,58(4):592-611
The aim of this paper is to study the asymptotic behavior of the solution of a convection–diffusion equation in perforated
domains with oscillating velocity and a Robin boundary condition which describes the adsorption on the bord of the obstacles.
Without any periodicity assumption, for a large range of perforated media and by mean of variational homogenization, we find
the global behavior when the characteristic size ε of the perforations tends to zero. The homogenized model, is a convection–diffusion
equation but with an extra term coming from the weak adsorption boundary condition. An example is presented to illustrate
the methodology. 相似文献
986.
Irena Rachůnková 《Czechoslovak Mathematical Journal》1999,49(2):241-248
We prove the existence of solutions of four-point boundary value problems under the assumption that f fulfils various combinations of sign conditions and no growth restrictions are imposed on f. In contrast to earlier works all our results are proved for the Carathéodory case. 相似文献
987.
We consider semidiscrete approximations of parabolic boundary value problems based on an elliptic approximation by J. Nitsche, in which the approximating subspaces are not subject to any boundary conditions. Optimal Lp (L 2) error estimates are derived for both smooth and nonsmooth boundary data. The approach is
based on semigroup theory combined with the theory of singular integrals. 相似文献
988.
989.
G. N. Gerasimov A. N. Pankratov A. P. Orlenko N. V. Kozlova E. A. Sinevitch E. N. Teleshov 《Macromolecular Symposia》1989,26(1):131-140
The polymerization of crystalline diacetylenes TS and DCH with different lattice structure was studied under high hydrostatic pressures (up to 4 kbar). It was shown that pressure increases the deformation of chain growing in monomer crystal. The features of such deformation depend on lattice structure that governs the influence of pressure on polymerization rate. We studied also polymerization of diacetylene HD crystals obtained in the pores of stretched polymer (PP). The field of polymer matrix influences the crystal state and the rate of polymerization. It was shown that the interaction of monomer crystals with the matrix leads to growth of more strained chains in these crystals. 相似文献
990.
George Georgiev Anna Tzoneva Lyudmil Lyutov Stefko Iliev Irena Kamenova Ventseslava Georgieva Elena Kamenska Andreas Bund 《Macromolecular Symposia》2004,210(1):393-401
The precipitation temperature (Tpr) value of aqueous poly(dimethylamino-ethoxyacryloyl-propylsulphonate) (PDMAPS) solutions decreases with the rise of electric field intensity both in the absence and in the presence of a low molecular salt. This electrostimulated Tpr shift is explained qualitatively by means of the model taking into account both the dominating intermacromolecular dipole-dipole interaction and the dipole cluster formation. 相似文献