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Conventional Processing (conventional + processing)
Selected AbstractsNuclear magnetic resonance data processing.CONCEPTS IN MAGNETIC RESONANCE, Issue 2 2003MestRe-C: A software package for desktop computers Abstract Magnetic Resonance Companion (MestRe-C) is a software package that offers state-of-the-art facilities for data processing, visualization, and analysis of high-resolution nuclear magnetic resonance (NMR) data, combined with a robust, user-friendly graphical interface that fully exploits the power and flexibility of the Windows platform. The program provides a variety of conversion facilities for most NMR spectrometer formats and includes all the conventional processing, displaying, and plotting capabilities of an NMR program, as well as more advanced processing techniques. A brief review of the basic concepts of NMR data processing is included also. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson Part A 19A: 80,96, 2003. [source] Ultrastructural preservation of rat embryonic dental tissues after rapid fixation and dehydration under microwave irradiationEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2000Luciana F. Massa Adequate preservation of the cells and matrix of mineralising tissues remains difficult, as organic components and initial mineral deposits may be lost during conventional processing for electron microscopy. In this study, we have reduced significantly the processing time using microwave irradiation. Rat molar tooth germs were fixed in 4% glutaraldehyde+4% formaldehyde with 0.1 M sodium cacodylate in a laboratory microwave oven for two periods of 20 s with a maximal temperature of 37°C. After conventional washing and post-fixation, specimens were dehydrated in graded ethanols under microwave irradiation for a total of 7 min 20 s. For comparison, some specimens were processed by conventional methods. After embedding, ultrathin sections were examined by electron microscopy. In differentiating ameloblasts and odontoblasts, plasma membranes, mitochondria, rough endoplasmic reticulum, the Golgi complex, together with all other cytoplasmic organelles exhibited excellent preservation. Microtubules, microfilaments and coated vesicles were particularly evident. Crystal-like mineral deposits were conspicuously present in relation to dentine matrix vesicles and collagen fibrils as well as in enamel matrix. The matrix of forming enamel had a globular electron-lucent appearance. It is concluded that this is a rapid method which provides a preserved or even improved morphology. [source] ,, T cell receptor repertoire in blood and colonic mucosa of rhesus macaquesJOURNAL OF MEDICAL PRIMATOLOGY, Issue 6 2000Eva Rakasz Although their precise roles are not well defined, ,, T lymphocytes are recognized as regular components of immune responses. These cells express a limited T cell receptor repertoire and they can be stimulated by soluble ligands without conventional processing and presentation by major histocompatibility antigens. Progress in this area has been limited by the substantial differences between murine and human ,, T cells and the lack of knowledge about these cells in nonhuman primates. We used molecular analysis of T cell receptor diversity to characterize ,, T cell populations from peripheral blood and colon of rhesus macaques (Macaca mulatta). The ,, T cell receptor diversity was limited and distinct for these tissue compartments, particularly in the TCRGV2 family. Furthermore, the TCRDV1+ subset of peripheral blood ,, T cells showed signs of progressive oligoclonalization as a function of age. Similar observations have been reported for human tissue samples and our results validate rhesus macaques as an appropriate animal model for studying primate ,, T cell populations. [source] Synthesis of Hydrated Aluminum Sulfate from Kaolin by Microwave ExtractionJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2000Seong Soo Park The feasibility of extracting alumina from kaolin via a microwave extraction process was investigated by comparing reaction times, reaction temperatures, and acid concentrations under microwave treatment with the same factors under conventional thermal extraction. The maximum amount of alumina extracted from kaolin under conventional processing at 90°C for 240 min with 1M H2SO4 was 99.9%; the same amount of alumina was extracted under microwave processing at 90°C for 120 min with 1M H2SO4. [source] Low-Temperature Synthesis of Bismuth Titanate Niobate (Bi7Ti4NbO21) Nanoparticles from a Metal-organic Polymeric PrecursorJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 5 2000Pedro Durán This paper describes the preparation of homogeneous Bi7Ti4NbO21 single-phase ceramic powders of ,55 nm crystallite size, at temperatures as low as 400°,500°C using a metal citrate complex method based on the Pechini-type reaction route. The thermal decomposition/oxidation of the polymerized resin, as investigated by TG/DTA, XRD, and SEM, led to the formation of a well-defined orthorhombic Bi7Ti4NbO21 compound with lattice parameters a= 0.544, b= 0.540, and c= 2.905 ± 0.0005 nm. Reaction takes place through an intermediate binary phase with a stoichiometry close to Bi20TiO32 which forms between 300° and 375°C. The metal-organic precursor synthesis method, where Bi, Ti, and Nb ions are first chelated to form metal complexes and then polymerized to give a gel, allows control of the Bi/Ti/Nb stoichiometric ratio leading to the rapid formation of nanosized bismuth titanate niobate (Bi7Ti4NbO21) ceramic powders, at temperatures much lower than usually needed by conventional processing of mixed-oxide powders. [source] Microwave and conventional curing of thick-section thermoset composite laminates: Experiment and simulationPOLYMER COMPOSITES, Issue 2 2001Erik T. Thostenson In conventional processing, thermal gradients cause differential curing of thick laminates and undesirable outside-in solidification. To reduce thermal gradients, thick laminates are processed at lower cure temperatures and heated with slow heating rates, resulting in excessive cure times. Microwaves can transmit energy volumetrically and instantaneously through direct interaction of materials with applied electromagnetic fields. The more efficient energy transfer of microwaves can alleviate the problems associated with differential curing, and the preferred inside-out solidification can be obtained. In this work, both microwave curing and thermal curing of 24.5 mm (1 inch) thick-section glass/epoxy laminates are investigated through the development of a numerical process simulation and conducting experiments in processing thick laminates in a conventional autoclave and a microwave furnace. Outside-in curing of the autoclave-processed laminate resulted in visible matrix cracks, while cracks were not visible in the microwave-processed laminate. Both numerical and experimental results show that volumetric heating due to microwaves promotes an inside-out cure and can dramatically reduce the overall processing time. [source] Properties and strain hardening character of polyethylene terephthalate containing IsosorbidePOLYMER ENGINEERING & SCIENCE, Issue 3 2009Ramesh M. Gohil Polyethylene terephthalate containing Isosorbide (PEIT) polymers made from renewable corn-derived Isosorbide monomer exhibit a wide range of glass transition temperatures (80,180°C) and are therefore able to be used in many applications. Stress,strain curves for high Isosorbide content copolymers show strain softening, which impairs the molecular orientation during orientation of films and bottles. It is therefore necessary to find ways to modify deformation behavior of PEIT copolymers. Deformation characteristics of PEIT and other polyesters have been evaluated to define stretching parameters and necessary composition for making oriented bottles for hot fill applications. In the presence of polymeric nucleating agents, (polymeric ionomers or polyesters containing sodium ions), strain-hardening parameters become almost temperature- independent below solid state deformation temperature of 125°C. We developed a methodology to achieve molecular orientation comparable with films and articles made by conventional processing of poly(ethylene terephthalate), PET. Polyesters containing sodium ions are efficient nucleating agents for PEIT, and their required concentration is dependent on deformation temperature. Both strain hardening and stress at 250% strain depend on the concentration of nucleating agents and deformation temperatures. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers [source] | |||||||||||||