• Resources Recycling
• /
• v.7 no.1
• /
• pp.14-19
• /
• 1998

Tile pl~ysimchemical properties of residual or unburned carbon obtaincd from fly ash were mestigated. The carbon-enrichcd samples were extracted from fly ash by flotalion mcthod. Tnz carbon content and chemical compos~lion of t b recovered carbon sample were analyzed. The ash in the carbon sample was also examined. The unburned carbon characterization included measurement oE sire distibution, sudace area, crystal shuchlre md density.

• Bulletin of the Korean Chemical Society
• /
• v.29 no.10
• /
• pp.1887-1892
• /
• 2008

Novel poly(aspartic acid) derivatives conjugated with L-lysine moieties and their amphiphilic analogs were synthesized and characterized. The chemical structures of these polymers were confirmed using FT-IR and $^1HNMR$ spectroscopy. The physicochemical properties of amphiphilic copolymers were characterized using an electrophonetic light scattering spectrophotometer (ELS) and transmission electron microscopy (TEM). These results indicated a stable nanoparticle formation within aqueous media. These polymers have potential applications in the pharmaceutical and cosmetic fields as delivery vehicles for bioactive molecules.

• Korean journal of food and cookery science
• /
• v.29 no.6
• /
• pp.833-839
• /
• 2013

Separated normal and waxy rice starches were pulverized, and the physicochemical and digestive properties of the starches were determined. The size of both starch granules significantly decreased (less than $8{\mu}m$) after pulverization. For pasting properties, significant decreases of peak and setback viscosity were observed in both of pulverized starches than in native ones. The lower pasting temperature as well as increased solubility and water binding capacity of pulverized starches imply molecular degradation of starch by pulverization. For thermal properties, onset temperature and melting enthalpy significantly decreased after pulverization, especially in normal rice starch, however there was no difference in amylose-lipid complex before andafter pulverization. The slowly digestible and resistant starch portion of normal rice starch increased after pulverization, however, in waxy rice starch, the rapidly digestible portion increased.

• Journal of the Korean Ceramic Society
• /
• v.25 no.2
• /
• pp.154-160
• /
• 1988

Almost single phase of Y1Ba2Cu3Ox, which exhibits the onset of superconducting transition at 90K, has been prepared via a conventional ceramic processing route followed by an anneal for a period of 10 hours at 45$0^{\circ}C$ in an atmosphere of 100% O2. The mean value for the oxygen content has been determined as x=6.85$\pm$0.02 by an iodometric titration technique. X-ray photoemission spectra are found to be consistent with a mixture of the d8(Cu3+) and d9(Cu2+) as the ground state and reveals that the local concentration of Cu3+ decreases with depth from the surface where x corresponds to 7.0. This is explained as being associated with the intercalation of oxygen during cooling from the annealing temperature.

• Journal of the Korean Ceramic Society
• /
• v.55 no.1
• /
• pp.85-89
• /
• 2018

This work reported the preparation and evaluation of a freshness-keeping film prepared by composite of a porous ceramic material such as vermiculite and polyethylene polymer. The ceramic material was pretreated physically and chemically to control the specific surface areas and particle size. A high content master-batch was prepared using the pretreated vermiculite. The master-batch, which contained 30% ceramic material, was mixed with a polymer material to prepare a film containing 3% vermiculite. The oxygen permeability and various physicochemical properties were evaluated for the prepared films. Compared to plain polyethylene film, the vermiculite loaded polyethylene film has a freshness maintenance property, indicating the creation of an improved film.

• Proceedings of the KIEE Conference
• /
• 2000.07c
• /
• pp.1708-1710
• /
• 2000

The synthesis and characterization of polymers for organic Metal/Insulator/Metal(MIM) devices were investigated from LB films. The physicochemical properties of the LB films were examined by UV absorption spectrum and AFM. The AFM images showed for network structure of polyurethane monolayer that the film formed an unsymmetry mesh with intermolecular interaction within the large scale. The stable images are probably due to a strong interaction between the monolayer film and Si substrate. We are unable to obtain molecular resolution in images of the films but did see a marked contrast between images of the bare substrate and those with the network structure film deposited onto it.

• Toxicological Research
• /
• v.26 no.2
• /
• pp.95-100
• /
• 2010

Nanoparticle exposure assessment presents a unique challenge in the field of occupational and environmental health. With the commercialization of nanotechnology, exposure usually starts from the workplace and then spreads to environment and consumer exposure. This report discusses the current trends of nanoparticle exposure assessment, including the definition of nanotechnology relevant terms, essential physicochemical properties for nanomaterial characterization, current international activities related nanomaterial safety, and exposure assessment standard development for nanotechnology. Further this report describes challenges of nanoparticle exposure assessment such as background measurement, metrics of nanoparticle exposure assessment and personal sampling.

• Entomological Research
• /
• v.48 no.6
• /
• pp.480-489
• /
• 2018

Due to the increasing interest in natural biopolymers including chitin, the exploitation of economic and easily accessible chitin sources with good physicochemical properties is nowadays required. In view of this fact, in the current study chitin was extracted and physicochemically characterized from six Cicadas (Hemiptera: Homoptera: Cicadoidea) species collected from Mediterranean region of Turkey (2014-15). Chitin was extracted using a classic extraction method that includes acid and base treatment. TGA results revealed a remarkable increase ($410-412^{\circ}C$) for all the six Cicada species compared to other chitin samples extracted from various sources. For all of the six selected species the chitin contents on the dry basis were determined as 6.7% for Cicadatra atra, 5.51% for C. hyalina, 8.84% for C. platyptera, 4.97% for Cicada lodosi, 6.49% for C. mordoganensis, and 5.88% for Cicadetta tibialis. The surface morphology of chitin isolates from Cicada species was observed to consist of nanofibers and nanopores.

• Bulletin of the Korean Chemical Society
• /
• v.20 no.3
• /
• pp.333-336
• /
• 1999

The polyaniline films with various insoluble parts are fabricated. The oxidation state (1-y) of these polyaniline is 0.53 and 0.54, respectively. To control the interchain and intrachain interaction of the polymer, the polyaniline films are stretched with appropriate ratio. The insoluble part of polyaniline synthesized at room temperature (low molecular weight) is 12%-76% and that of polyaniline synthesized at 0 'IC (intermediate molecular weight) is 65%-89%. The low molecular weight polyaniline films with various drawing ratios have amorphous structure. In the intermediate weight polyaniline films, the crystallinity of films increases with drawing ratio as well as insoluble part. The difference of the insoluble part affects electrical conductivity which is increased dramatically with draw ratio. In particular, the higher insoluble part caused greater increase in electrical conductivity.

• Genomics & Informatics
• /
• v.21 no.2
• /
• pp.25.1-25.12
• /
• 2023

Adaptation of infections and hosts has resulted in several metabolic mechanisms adopted by intracellular pathogens to combat the defense responses and the lack of fuel during infection. Human tuberculosis caused by Mycobacterium tuberculosis (MTB) is the world's first cause of mortality tied to a single disease. This study aims to characterize and anticipate potential antigen characteristics for promising vaccine candidates for the hypothetical protein of MTB through computational strategies. The protein is associated with the catalyzation of dithiol oxidation and/or disulfide reduction because of the protein's anticipated disulfide oxidoreductase properties. This investigation analyzed the protein's physicochemical characteristics, protein-protein interactions, subcellular locations, anticipated active sites, secondary and tertiary structures, allergenicity, antigenicity, and toxicity properties. The protein has significant active amino acid residues with no allergenicity, elevated antigenicity, and no toxicity.