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61.
Previously reported studies on crosslinked castable poly(dimethylsiloxanes) have been extended. A series of dimethylsiloxane difumarates were copolymerized with styrene, and some of their rheological properties were determined. Investigation of these and previously prepared polymers has shown that segregation on a microscale can take place in two-component crosslinked systems with relatively short network chains. This may occur even if one of the components is a nonpolymeric species involved in crosslinking. Microheterogeneity was observed in systems made up of prepolymer chains of a single type, when these were short enough to expose a specific structure of the crosslinking site. It seems that microheterogeneity can be expected in crosslinked polymers when the size of the crosslinking site is significant in comparison with the network chain length and when its cohesive energy density differs considerably from that of the main network chains. Additional factors affecting microphase separation include the existence of physical interactions between chemical groups, steric positioning of interacting groups during the process of crosslinking, and physical effects of the degree of crosslinking leading to local differences in the density of the system. 相似文献
62.
Although the contortions required are unprecedented, the benzynes formed by the fluoride-induced elimination of TMSOTf from o-trimethylsilyl [6]- and [7]-helicenol triflates add to another ring of the helicenes rather than to an external furan molecule. 相似文献
63.
Theoretical predictions and experimental observations show that a weak harmonic seed beam can control the process of generating multiple quadratic solitons in periodically poled KTiOPO4 by inputting only a fundamental beam. This all-optical switching does not depend on the relative phase of the input beams, an unusual property for such coherent solitons. 相似文献
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Bioelectronics is a rapidly progressing interdisciplinary research field that has important implications for the development of biosensors, biofuel cells, biomaterial-based computers, and bioelectronic devices. Magneto-controlled molecular electronics and bioelectronics are new topics that examine the effect of an external magnetic field on electrocatalytic and bioelectrocatalytic processes of functionalized magnetic particles associated with electrodes. In this article we describe the progress in the developments of magneto-switchable electrocatalytic and bioelectrocatalytic transformations, and the effects of the rotation of the magnetic particles on the electrocatalytic and bioelectrocatalytic processes are discussed. Finally, the implications of the results on the development of biosensors, amplified immunosensors, and DNA sensors are described. 相似文献
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Wallace Feurzeig Gabriel Katz Philip Lewis Victor Steinbok 《International Journal of Computers for Mathematical Learning》2000,5(3):283-284
Volume Contents
Volume Contents 相似文献68.
Novel biomaterials are beneficial to the growing fields of drug delivery, cell biology, micro‐devices, and tissue engineering. With recent advances in chemistry and materials science, light is becoming an attractive option as a method to control biomaterial behavior and properties. In this Feature Article, we explore some of the early and recent advances in the design of light‐responsive biomaterials. Particular attention is paid to macromolecular assemblies for drug delivery, multi‐component surface patterning for advanced cell assays, and polymer networks that undergo chemical or shape changes upon light exposure. We conclude with some remarks about future directions of the field.
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Amplified DNA sensing and immunosensing by the rotation of functional magnetic particles 总被引:1,自引:0,他引:1
Weizmann Y Patolsky F Katz E Willner I 《Journal of the American Chemical Society》2003,125(12):3452-3454
Amplified chemiluminescent detection of DNA-complementary DNA or of antigen-antibody interactions is accomplished in the presence of rotating functionalized magnetic particles. 相似文献