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31.
Kamat NP Robbins GP Rawson JS Therien MJ Dmochowski IJ Hammer DA 《Advanced functional materials》2010,20(16):2588-2596
Polymersomes are vesicles whose membranes are comprised of self-assembled block co-polymers. We recently showed that co-encapsulating conjugated multi-porphyrin dyes in a polymersome membrane with ferritin protein in the aqueous lumen confers photo-lability to the polymersome. In the present study, we illustrate that the photo-lability can be extended to vesicles containing dextran, an inert and inexpensive polysaccharide, as the luminal solute. Here we explore how structural features of the polymersome/porphyrin/dextran composite affect its photo-response. Increasing dextran molecular weight, decreasing block copolymer molecular weight, and altering fluorophore-membrane interactions results in increasing the photo-responsiveness of the polymersomes. Amphiphilic interactions of the luminal encapsulant with the membrane coupled with localized heat production in the hydrophobic bilayer likely cause differential thermal expansion in the membrane and the subsequent membrane rupture. This study suggests a general approach to impart photo-responsiveness to any biomimetic vesicle system without chemical modification, as well as a simple, bio-inert method for constructing photo-sensitive carriers for controlled release of encapsulants. 相似文献
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LED显示技术作为现代信息社会的重要标志之一,已经被广泛应用于多个行业中.从专利信息分析的角度,从LED显示技术历年专利申请量、重要申请人、IPC分类情况以及国内重要企业技术构成进行了分析,探讨了LED显示技术的发展过程,介绍了LED显示技术的行业的发展现状,为相关企业明晰行业动态,实现知识产权战略布局提供了有效依据. 相似文献
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The emergence of quantum computer will threaten the security of existing public-key cryptosystems, including the Diffie Hellman key exchange protocol, encryption scheme and etc, and it makes the study of resistant quantum cryptography very urgent. This motivate us to design a new key exchange protocol and eneryption scheme in this paper. Firstly, some acknowledged mathematical problems was introduced, such as ergodic matrix problem and tensor decomposition problem, the two problems have been proved to NPC hard. From the computational complexity prospective, NPC problems have been considered that there is no polynomial-time quantum algorithm to solve them. From the algebraic structures prospective, non-commutative cryptography has been considered to resist quantum. The matrix and tensor operator we adopted also satisfied with this non-commutative algebraic structures, so they can be used as candidate problems for resisting quantum from perspective of computational complexity theory and algebraic structures. Secondly, a new problem was constructed based on the introduced problems in this paper, then a key exchange protocol and a public key encryption scheme were proposed based on it. Finally the security analysis, efficiency, recommended parameters, performance evaluation and etc. were also been given. The two schemes has the following characteristics, provable security,security bits can be scalable, to achieve high efficiency, quantum resistance, and etc. 相似文献
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合成具有光敏性的聚酰亚胺OPDA-BAPAF-Cin-CN,对其化学性质进行研究。用这种聚酰亚胺作为光致取向剂,能对液晶MLC-LC2000有良好的取向效果。研究了这种取向剂对液晶MLC-LC2000的取向方向及提高预倾角的作用,发现该取向剂有良好的热稳定性。 相似文献
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Parambath Anilkumar Edmond Gravel Ioanna Theodorou Karine Gombert Benoit Thézé Frédéric Ducongé Eric Doris 《Advanced functional materials》2014,24(33):5246-5252
The development of a photo‐responsive micellar system capable of triggering cell death is reported. Precursors of the micelles are synthesized by connecting a lipophilic chain to a hydrophilic polyethylene glycol via a photo‐labile nitrobenzyl group. The resulting amphiphilic units are self‐assembled in water forming 12 nm micelles that are readily internalized into cells. Upon photo‐irradiation, micelles undergo cleavage and yield a cytotoxic nitrosobenzaldehyde derivative, which significantly inhibits the proliferation of MDA‐MB‐231 cells under standard in vitro conditions. 相似文献