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复合改性纳米碳酸钙/CPE对PVC的协同增韧增强 总被引:3,自引:0,他引:3
用改性剂在水相中对纳米碳酸钙进行表面改性,样品烘干后在捏合机中用固相法采用自制的表面改性剂对水相法改性的纳米碳酸钙进一步进行包覆改性;制备了一种具有反应活性的新型改性纳米碳酸钙(R-CaCO3),并对R- CaCO3进行表征。结果表明,R-CaCO3亲油性增加,在液体石蜡中分散性改善,改性剂与碳酸钙之间形成化学吸附; 同时制备了PVC/CPE/R-CaCO3]纳米复合材料,发现R-CaCO3与CPE对PVC有明显的协同增韧增强作用,同时还提高了体系的耐热性,且体系的黏度基本不变。 相似文献
53.
A new characterization procedure for aqueous solutions with unknown composition was proposed based on the binomial distribution
of TOC (total organic carbon) fraction in terms of a characterizing variable, the Freundlich coefficient, k, so that the solution
in question can be described by a finite number of pseudo.species identified with a certain k value. The validity and computational
accuracy of this procedure has been demonstrated by characterizing three sets of experimental data chosen from different sources.
Predictions based on this procedure yielded acceptable results that agreed closely with experimental data. 相似文献
54.
We present an interactive method for mesh segmentation that is inspired by the classical live‐wire interaction for image segmentation. The core contribution of the work is the definition and computation of wires on surfaces that are likely to lie at segment boundaries. We define wires as geodesics in a new tensor‐based anisotropic metric, which improves upon previous metrics in stability and feature‐awareness. We further introduce a simple but effective mesh embedding approach that allows geodesic paths in an anisotropic path to be computed efficiently using existing algorithms designed for Euclidean geodesics. Our tool is particularly suited for delineating segmentation boundaries that are aligned with features or curvature directions, and we demonstrate its use in creating artist‐guided segmentations. 相似文献
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Jakobi et al. for the first time proposed a novel and practical quantum private query (QPQ) protocol based on SARG04 (Scarani et al. in Phys Rev Lett 92:057901, 2004) quantum key distribution protocol (Jakobi et al. in Phys Rev A 83:022301, 2011). Gao et al. generalized Jakobi et al’s protocol and proposed a flexible QPQ protocol (Gao et al. in Opt Exp 20(16):17411–17420, 2012). When $\theta <\pi /4$ , Gao et al’s protocol exhibits better database security than Jakobi et al’s protocol, but has a higher probability with which Bob can correctly guess the address of Alice’s query. In this paper, we propose a flexible B92-based QPQ protocol. Although SARG04 protocol is a modification of B92 protocol and can be seen as a generalization of B92 protocol, our protocol shows different advantages from Gao et al’s protocol. It can simultaneously obtain better database security and a lower probability with which Bob can correctly guess the address of Alice’s query when $\theta <\pi /4$ . By introducing entanglement, the proposed QPQ protocol is robust against channel-loss attack, which also implies lower classical communication complexity. Similar to Gao et al’s protocol, it is flexible, practical, and robust against quantum memory attack. 相似文献
58.
醇酮装置废酸水中副产物的回收利用探讨 总被引:1,自引:0,他引:1
分析了醇田装置副产物的生成过程和借鉴国外辞酮装置废酸水和皂化废碱液的回收利用技术,提出了合并浓缩、脱过氧化氢生产混合二元酸及硝酸后氧化、结晶、真空间歇精馏相结合分高己二酸、戊二酸、丁二酸的两种回收利用的工艺方法,并提出了两个工业化装置的设想,对治理废酸水提出了建设性意见。 相似文献
59.
Ju Kumanotani 《Progress in Organic Coatings》1997,34(1-4):135-146
The chemistry and technology of oriental lacquer, proof of long-term durability by a laboratory test, and morphological features of the closely packed shell (polysaccharides–glycoproteins)–core (polymerized urushiol) microgel particles, which are chiefly responsible for degradation due to efflorescence outdoors, are described. The dimerization mechanism of urushiol was demonstrated by separation of over 20 urushiol dimer derivatives. Physiological dimerization of urushiol in the lacquer is very much influenced by the humidity in drying, and the interaction of semiquinone radicals with metal ions, hydrophilic polysaccharides and amphipathic glycoproteins contained in the lacquer. A mechanism for renewable oriental lacquer is proposed, involving harmony of technology and nature within the lacquer tree plantations in south-east Asia. A brief review of studies of lacquer chemistry and synthetic coatings is given. 相似文献
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