Structural characteristics research

Most researchers were not apparently aware of earlier CNT preparations in the context of ultra-thin vapour-grown carbon fibres (VGCF). This type of CNT is termed pyrolytic (PCNT) and its preparation shows promise of large-scale synthesis. Needless to say, it is of practical importance to provide sufficient CNTs at reasonable cost. This chapter highlights the preparation methods, structural characteristics and current commercial status of PCNTs and includes a description of the devices used hitherto to obtain aligned PCNTs. By way of... 

To promote the use of poor quality water for irrigation, a field research study was conducted in three semi-arid regions with water scarceness in Syria in order to define, under field conditions, the wheat yield response function to irrigation water salinity, the effect of soil texture and structural characteristics on the irrigation water salinity threshold, and to compare this value with the conventional threshold value. 

Urade, Y., el al. (2006b). Biochemical and structural characteristics of hematopoietic prostaglandin D synthase from evolutionary analysis to drug designing. Functional and Structural Biology on the Lipo-network, 2006, Transworld Research Network, Kerala, India, pp. 135-64. 

In view of the increasing level of research activities associated with the application of HP-CEC for peptide analysis, it can be confidently expected that new miniaturized, high-throughput separation systems will become available over the next several years, fully integrated with MS/MS instrumentation and other types of spectrometers capable of determining structural characteristics of the resolved peptides at the low nanomole level. 

There has been available (or some years unarguable evidence that each of the major macerals groups has a distinct set of structural characteristics, and that the major macerals in any one coal do differ materially in chemical structure from each other. We must therefore admit that chemical structures alleged to represent whole coals are futile, and that basic chemical research should use single macerals in as pure a state as possible. On the other hand, some believe that pure vitrinite macerals at least can be represented usefully by a model structure. 

As a physician, Burke knew a great deal about the biology of skin function, but not as much about the structural characteristics of a possible skin substitute. To help him with this part of his research, Burke turned to loannis V. Yannas, then assistant professor of fibers and polymers in the Department of Mechanical Engineering at the Massachusetts Institute of Technology (MIT), just across the Charles River from MGH. Working together Burke and Yannas developed the first successful skin substitute by 1977. In November of that year, they were awarded a patent for a "Multilayer Membrane Useful as Synthetic Skin."... 

The diffusion of small molecules in polymeric solids has been a subject in which relatively little interest has been shown by the polymer chemist, in contrast to its counterpart, i.e., the diffusion of macromolecules in dilute solutions. However, during the past ten years there has been a great accumulation of important data on this subject, both experimental and theoretical, and it has become apparent that in many cases diffusion in polymers exhibits features which cannot be expected from classical theories and that such departures are related to the molecular structure characteristic of polymeric solids and gels. Also there have been a number of important contributions to the procedures by which diffusion coefficients of given systems can be determined accurately from experiment. It is impossible, and apparently beyond the author s ability, to treat all these recent investigations in the limited space allowed. So, in this article, the author wishes to discuss some selected topics with which he has a relatively greater acquaintance but which he feels are of fundamental importance for understanding the current situation in this field of polymer research. Thus the present paper is a kind of personal note, rather than a balanced review of diverse aspects of recent diffusion studies. 

After investigating the recent literature, we have seen that most recent efforts connected with the use of liposome in therapeutics are mainly connected with the treatment of cancer. This is the reason why here we deal with the most common cancer types (brain, breast, lung, and ovarian cancer), and ongoing research and clinical treatments are discussed in more detail. However, we do not want to imply that the future of liposomes in drug delivery is limited to cancer therapy. Indeed, liposome structure, characteristics, and versatility are sure to find, in... 

Another way to explore comes from a new result recently evidenced in our group, which was just cited in the introduction. It concerns VSB-1 (for Versailles Santa Barbara), a nickel oxyfluorophosphate [22] which is together porous, magnetic and ion exchanger, and which exhibits the largest pores ever discovered with synthetic solids. Indeed the tunnels are 24-rings (Fig. 16). Beside its structural characteristics, it provides also one of the rare examples of a porous solid with only water as template. If one remembers that the largest known pores exist in the mineral Cacoxenite [80], and that these pores are filled only by water molecules, this probably represents a new field of research in this area. 

Fabrication of protein nanotubes has the potential to lead food science and engineering to new heights. However further studies need to be conducted to fulfill the promise in many potential food applications. Interactions of nanotubes with the materials to be encapsulated— their structures, characteristics and controlled release properties—should be studied using the model or actual food systems. Another important area of future research is the investigation of the self-assembly characteristics of other food proteins that can be used for similar purposes. 

Calixarenes were developed later than crown ethers and cyclodextrins but have stillbeen extensively researched. Macrocycles of calix[n]arenes are constructed by linking a number of phenol residues via methylene moieties (Fig. 2.16). Like crown ethers, the name calixarene reflects the structures of these molecules, since a calix is a chalice. Calixarenes with various cavity sizes have been designed, each of which has conformation isomers, and their phenolic hydroxyl groups are often modified. These structural characteristics allow us to create calixarene derivatives with various structural modifications. 

In this paper, we review the main results obtained so far in the field of inverse microemulsion polymerization. The role played by the monomers on the structural characteristics of the microemulsion prior to polymerization will be emphasized. The main properties of the final latices will be discussed in light of both basic and applied research. 

Fig. (8). Representation of the main structural characteristics of peptides with a p-hairpin fold. Peptides are formed by antiparallel two-strand P-sheet stabilized by several hydrogen bonds (hatched lines) and by disulphide bridges. Modified with permission from [109]. Copyright (2002) Research Signpost.

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