WASTE LEATHER PARTICLES AS A FILLER FOR POLY(VINYL CHLORIDE) PLASTISOLS

Waste leather granules were incorporated into poly(vinyl chloride) plastisols containing di-octyl phthalate as plasticizer. The rheological behavior and gelling characteristics of plastisols were investigated and the filled samples were tested for their physicomechnical properties. It was found that density, wear resistance and Shore D hardness of composites increase whereas the tensile properties are considerably deteriorated with the incorporation of leather. In order to improve mechanical properties, treatment of the leather granules was applied with a solution of ethylene vinyl acetate (EVA) copolymer. This seemed to produce a coating that promotes adhesion as well as proper wetting of the granules and, thus, significantly improves the tensile characteristics of specimens. The upper level of leather content, in order to produce filled products with acceptable properties, was estimated at the concentration of 50 phr. This is an extension to the limits of the system plasticized poly(vinyl chloride)/leather determined in the case of its processing via melt mixing techniques.     

Intramolecular Charge Transfer Complexes. 4. Poly(N-(2-hydroxyethyl)carbazolyl Acrylate-co-Picryl Methacrylate)

Abstract

Radical copolymerization of N-(2-hydroxyethyl)carbazolyl acry-late with picryl methacrylate takes place mainly through the inter-monomeric charge transfer complex (CTC) in dioxane solution. When the solvent is 1, 2-dichloroethane, concurrent chain transfer reactions arise. The copolymers obtained are intramolecular CTC. The charge transfer interaction depends on copolymer composition and conformation, and on the copolymerization solvent.     

The lattice structure of the set of stable outcomes of the multiple partners assignment game

The Multiple Partners assignment game is a natural extension of the Shapley and Shubik Assignment Game (Shapley and Shubik, 1972) to the case where the participants can form more than one partnership.  In Sotomayor (1992) the existence of stable outcomes was proved. For the sake of completeness the proof is reproduced in Appendix I. In this paper we show that, as in the Assignment Game, stable payoffs form a complete lattice and hence there exists a unique optimal stable payoff for each side of the market. We also observe a polarization of interests between the two sides of the matching, within the whole set of stable payoffs. Our proofs differ technically from the Shapley and Shubik's proofs since they depend on a central result (Theorem 1) which has no parallel in the Assignment model. Received: June 1996/Revised version: February 1999     

淀粉黄原酸酯的合成改进及其应用研究

改进了不溶性淀粉黄原酸酯(ISX)的合成工艺,并研究了合成的ISX在若干废水中去除Cu(Ⅱ)、Fe(Ⅱ)离子的影响因素和工艺条件.此外,还探索了ISX合成过程中的反应废液的回用及处理废水后的污泥回收再利用技术.     

多晶GeSe薄膜的制备及在太阳能电池中的应用

硒化亚锗(GeSe)由于具有原材料储量丰富、绿色无毒、组成简单、稳定以及吸光系数高等优势,很适合被用于制备薄膜太阳能电池的光吸收层。然而,目前对其研究较少,其主要难点在于如何制备高质量的多晶GeSe薄膜。本工作采用物理气相沉积法制备GeSe薄膜,之后通过硫化铵溶液及退火处理,有效地将非晶GeSe转变为多晶GeSe。将其组装成简单平面薄膜结构太阳能电池器件后,相比于未处理的非晶GeSe太阳能电池,电池的光电流有了显著提升,对应的电池效率提升了13倍左右。进一步将未封装的电池放置在空气中一个月后,发现其仍能保持原有效率,证明其具有优异的稳定性。     

Stiffness-Transformable Nanoplatforms Responsive to the Tumor Microenvironment for Enhanced Tumor Therapeutic Efficacy

Herein, we report, for the first time, a unique stiffness-transformable manganese oxide hybridized mesoporous organosilica nanoplatform (MMON) for enhancing tumor therapeutic efficacy. The prepared MMONs had a quasi-spherical morphology and were completely transformed into soft bowl-like nanocapsules in the simulated tumor microenvironment through the breakage of Mn−O bonds, which decreased their Young's modulus from 165.7 to 84.5 MPa. Due to their unique stiffness transformation properties, the MMONs had reduced macrophage internalization, improved tumor cell uptake, and enhanced penetration of multicellular spheroids. In addition, in vivo experiments showed that the MMONs displayed a 3.79- and 2.90-fold decrease in non-specific liver distribution and a 2.87- and 1.83-fold increase in tumor accumulation compared to their soft and stiff counterparts, respectively. Furthermore, chlorin e6 (Ce6) modified MMONs had significantly improved photodynamic therapeutic effect.