Hybrid development novel approaches

A novel approach is reported for the accurate evaluation of pore size distributions for mesoporous and microporous silicas from nitrogen adsorption data. The model used is a hybrid combination of statistical mechanical calculations and experimental observations for macroporous silicas and for MCM-41 ordered mesoporous silicas, which are regarded as the best model mesoporous solids currently available. Thus, an accurate reference isotherm has been developed from extensive experimental observations and surface heterogeneity analysis by density functional theory the critical pore filling pressures have been determined as a function of the pore size from adsorption isotherms on MCM-41 materials well characterized by independent X-ray techniques and finally, the important variation of the pore fluid density with pressure and pore size has been accounted for by density functional theory calculations. The pore size distribution for an unknown sample is extracted from its experimental nitrogen isotherm by inversion of the integral equation of adsorption using the hybrid models as the kernel matrix. The approach reported in the current study opens new opportunities in characterization of mesoporous and microporous-mesoporous materials. 

The novel approach for calculation of pore size distributions, which is reported in the current study is based on recent developments in the materials science and in the theory of inhomogeneous fluids. First, an application of experimental adsorption data for well-characterized MCM-41 silicas enabled proper calibration of the pore size analysis. Second, an application of a modem theory to describe the behavior of inhomogeneous fluids in confined spaces, that is the non-local density functional theory [6], allowed the numerical calculation of model isotherms for various pore sizes. In addition, a practical numerical deconvolution method that provides a "best fit" solution representing the pore distribution of the sample was implemented [7, 8]. In this paper we describe a deconvolution method for estimating mesopore size distribution that explicitly allows for unfilled large pores, and a method for creating composite, or hybrid, models that incorporate both theoretical calculations and experimental observations. Moreover, we showed the applicability of the new approach in characterization of MCM-41 and related materials. 

Senthil-Kumar, M., V. Srikanthbabu, B. Mohan Raju, Ganeshkumar, N. Shivaprakash, and M. Udayakumar. 2003. Screening of inbred bnes to develop a thermotolerant sunflower hybrid using the temperature induction response (TIR) technique a novel approach by exploiting residual variabibty. J. Exp. Bot. 54 2569-2578. 

The paper is devoted to development of novel approach to dope coatings with active anticorrosion species with self-healing ability. They contain nanoreservoirs which can store active agents and provide controllable release of them. The titania nanoparticles doped with cerium ions and organic inhibitors were used as nanocontainers to dope the hybrid sol-gel matrix and to provide long-term corrosion protection. 

To minimize or eliminate reliance on ethylene oxide and exploit reliability of assured sterility using radiation for absorbable polymers and particularly those used in tissue engineering, Shalaby and co-workers developed the radiochemical sterilization (RC-S) process. The RC-S process represents a novel approach to the sterilization of certain mechanical devices, such as those made of absorbable polyesters, that are sensitive to high-energy radiation delivered at the traditional dose of 25 kGy. RC-S is a hybrid process encompassing the attributes of chemical high-energy radiation sterilization without the drawbacks associated with the use of the parent processes. RC-... 

Novel Approaches in Hybrid Solar Cell Development 381... 

This approach was followed concurrendy with that of steroids as part of platinum coordination complexes for which the principal target was found to be DNA. Despite many structural modifications, the results were not spectacular [104-106]. Very often these Pt hybrids or their associated SERMs provided no synergy [107], as far as new, useftil properties were concerned. On the other hand, with covalent organometallic complexes, a number of pioneering results made it possible to study their recognition for specific nuclear receptors, and to develop novel affinity markers or suicide substrates. These preferentially targeted key proteins in specific biological functions to the detriment of DNA. 

Ren L., Tsuru K., Hayakawa S., Osaka A. Synthesis and characterization of gelatin-siloxane hybrids derived through sol-gel procedure. J. Sol-Gel Sci Technol, 2001 21 115-121 Ren L., Tsuru K., Hayakawa S., Osaka A. Novel approach to fabricate porous gelatin-siloxane hybrids for bone tissue engineering. Biomaterials 2002 23 4765 773 Rietti-Shati M., Rouen, D., Mandelbaum, R.T. Atrazine degradation by Pseudomonas strain ADP entrapped in sol-gel glass. J. Sol-Gel Sci. Technol. 1996 7 77-79 Rupcich N., Goldstein A., Brennan J.D. Optimization of sol-gel formulations and surface treatments for the development of pin-printed protein microarrays. Chem. Mater. 2003 15 1803-1811... 

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