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71.
Asteria Luzardo‐Álvarez Álvaro Antelo‐Queijo Victor H. Soto José Blanco‐Méndez 《应用聚合物科学杂志》2012,123(6):3595-3604
Hydrophobically modified chitosan containing β‐cyclodextrin (CD) units was synthesized by using tosylated β‐CD. The final product was characterized by Fourier transform infrared (FTIR) spectroscopy, elemental analysis and TGA, and rheometry. The polymer bearing β‐CD moieties was used to obtain crosslinked microparticles by spray‐drying which could then be used in a controlled release system for drugs. FTIR confirmed the formation of an amide linkage between cyclodextrin and chitosan. As fluorescence spectroscopy demonstrated, hydrophobic microenvironments were formed by chitosan bearing cyclodextrin in solution at lower concentrations than for chitosan. Rheometry and FTIR showed the crosslinking of the new polymer using genipin, a molecule of natural origin. Microspheres (MS) obtained by spray‐drying showed narrow size distribution when β‐CD was grafted onto chitosan and ξ‐potential of MS was slightly lower although it remained positive. In conclusion, β‐CD linked chitosan polymer can be considered as a very promising controlled drug delivery system for drugs. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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Multimedia Tools and Applications - Ubiquitous and networked sensors impose a huge challenge for privacy protection which has become an emerging problem of modern society. Protecting the privacy of... 相似文献
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77.
SVEN AXSÁTER 《国际生产研究杂志》2013,51(6):669-688
In most cases real world subsystems for inventory and production control are designed according to very elementary control principles. In order to control the total system, some kind of coordinating control of the subsystems is needed. The approach pursued in this paper is to control the over-all-system by varying different control-parameters of the subsystems. The control system is therefore regarded as a two-level hierarchical system. Coordinating control is carried out with the aid of simple dynamic models based on aggregate terms. Problems concerning the identification of inventory-dynamics ore highlighted. In order to show how the models developed can be used efficiently for coordinating the control of an integrated production-inventory system, a simple control principle is applied to a simulated system. 相似文献
78.
JOSÉ C. GONZÁLEZ 《国际通用系统杂志》2013,42(4):394-397
79.
Gerardo Valadez Huerta Johanan Álvarez Jordán Michael Dragon Keno Leites Stephan Kabelac 《International Journal of Hydrogen Energy》2018,43(34):16684-16693
Solid oxide fuel cell (SOFC) systems with anode off-gas recirculation (AGR) and diesel pre-reforming are advantageous because they can operate with the current fuel infrastructure. In the SchIBZ-project, the prototype of such a SOFC system for maritime applications has already been commissioned. In this first paper, we model the system devices to conduct an exergy analysis of this real SOFC plant and validate them with experimental values from experiments in laboratory scale. The results of our simulation agree well with the experimental values. The calculations with the validated results may be closer to the real thermodynamic behavior of such system components than previous literature. 相似文献
80.
Rodolfo Daniel Velasco-Barraza Ricardo Vera-Graziano Eduardo Alberto López-Maldonado Mercedes Teresita Oropeza-Guzmán Syed G. Dastager Adriana Álvarez-Andrade 《国际聚合物材料杂志》2018,67(13):800-807
In recent times, electrospun nanofibers have been widely studied from several biotechnological approaches; in this work, poly(acrylic acid) (PAA) solutions mixed with chitosan and alginate were electrospun and characterized to determine the behavior of these fibers when used in combination with bacteria, different samples were incubated with the bacterial strains: Streptomyces spp., Micromonospora spp., and Escherichia coli and a OD600 test was performed. The formation of nanofibers via electrospinning and the physicochemical properties of the obtained fibers were evaluated. Results showed that the presence of chitosan enhanced the thermal stability of PAA, since PAA/alginate fibers lost 5% of their mass at 41°C, whereas PAA/chitosan lost this amount at around 125°C. The fibers demonstrated suitable characteristics to be used as a bacteria bioreactor. 相似文献