• Carbon letters
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• v.5 no.3
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• pp.118-126
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• 2004

MCMB (Mesocarbon microbeads) is a kind of anode material for lithium-ion secondary battery. MCMB charge/discharge cycle stability is one of the important criterion at lithium-ion battery operation. In this study, the cycling stability of a lithium-ion secondary battery has been examined. MCMB was made by the direct solvent extraction method. After the MCMB was carbonized and graphitized, the measurement of charge/discharge capacity and efficiency were carried out. In the result, discharge capacity of MCMB in the initial cycle was above 290.0 mAh/g. After the second cycle, efficiency of charge/discharge MCMB was about 98%. These results were similar to the commercial MCMB product.

• Journal of Sericultural and Entomological Science
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• v.18 no.2
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• pp.83-88
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• 1976

A study was made on the interstrain difference in dose-infection response and induction response of silkworm to the two strains of cytoplasmic polyhedrosis virus to obtain some informations on screening the leading strains. Comparison of dose-infection responses of larvae following the inoculation of the inclusion body of cytoplasmic polyhedrosis virus revealed that there is no significance in the resistance to dose-infection and any of strains were more resistant at advanced stage(4th instar) than younger stage(2nd instar). In the pathogenicity between cytoplasmic polyhedrosis virus with hexagonal and tetragonal outline, the hexagonal polyhedra showed higher pathogenicity than the tetragonal polyhedra. However, the averages of $LC_{50}$ of cytoplasmic polyhedrosis virus with hexagonal outline to larvae of parental inbred line were 6.12${\times}$10$\^$6//$m\ell$ at 2nd instar and 1.57${\times}$10$\^$7//$m\ell$ at 4th instar in spring and those to their hybrids were 1.28${\times}$10$\^$6//$m\ell$ at 2nd ins tar and 4.99${\times}$10$\^$6//$m\ell$ at 4th ins tar in autumn. Meanwhile the $LC_{50}$ averages of tetragonal polyhedra. to larvae of parental inbred line were 2.06${\times}$10$\^$7//$m\ell$ at 2nd instar and 5.67${\times}$10$\^$7//$m\ell$ at 4th instar in spring and those to their hybrids were 9.84${\times}$10$\^$6//$m\ell$ at 2nd instar and 3.86${\times}$10$\^$7//$m\ell$ at 4th instar in autumn, respectively. In comparison of induction response of silkworm larvae to inoculation of tetragonal polyhedra of cytoplasmic polyhedrosis virus, the induction rate of hexagonal polyhedra was remarkably higher in the treatment of inoculation at 2nd instar than at 4th instar and at the concentration of 1.3${\times}$10$\^$6//$m\ell$ than at any others. Most of induction showed a mixed infection with hexagonal and tetragonal polyhedra of cytoplasmic polyhedrosis virus.

• Applied Chemistry for Engineering
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• v.32 no.5
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• pp.581-588
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• 2021

In this study, soil slurry bioreactors were used to treat soils containing 16 polycyclic aromatic hydrocarbons (PAHs) for 35 days. Five different soil samples were taken from manufactured gas plant (MGP) and coal tar disposal sites. Soil properties, such as carbon content and particle distribution, were measured. These properties were significantly correlated with percent biodegradation and degradation rate. The cumulative amount of PAH degraded (P), degradation rate (K_m), and lag phase (𝜆) constants of PAHs in different MGP soils for 16 PAHs were successfully obtained from nonlinear regression analysis using the Gompertz equation, but only those of naphthalene, anthracene, acenaphthene, fluoranthene, chrysene, benzo[k]fluoranthene, benzo(a)pyrene, and benzo(g,h,i)perylene are presented in this study. A comparison between total non-carcinogenic and carcinogenic PAHs indicated higher maximum amounts of PAH degraded in the former than that in the latter owing to lower partition coefficients and higher water solubilities (S). The degradation rates of total non-carcinogenic compounds for all soils were more than four times higher than those of total carcinogenic compounds. Carcinogenic PAHs have the highest partitioning coefficients (K_oc), resulting in lower bioavailability as the molecular weight (MW) increases. Good linear relationships of K_m, 𝜆, and P with the octanol-water partitioning coefficient (K_ow), MW, and S were used to estimate PAH remaining, lag time, and biodegradation rate for other PAHs.

• Progress in Medical Physics
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• v.19 no.2
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• pp.131-138
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• 2008

We evaluated on the calculation accuracy of treatment planning system (TPS) with phantom having convex and concave surface. The TPS is Eclipse (Varian, USA) using both algorithms AAA and PBC for photon dose calculations. PBC algorithms have three corrections of Batho, modified Batho (M-Batho), and equivalent TAR (E-TAR). The field sizes were $10{\times}10\;cm^2$ and $20{\times}20\;cm^2$, and MLC-shaped fields for these fields. We measured doses at three depths 5, 10 and 15cm in phantom of SSD=90cm in the condition of inserted farmer chamber. For given conditions, we have calculated dose with these algorithms and compared them with measured doses. In AAA the calculated doses (dose/MU) were agreed to measured doses within ${\pm}1%$ in flat and convex surface and were under estimated with -1.9% maximum in concave surface. In PBC the calculated doses were over estimated with +1.7% and +4.1% respectively in flat and convex surface and the differences were from -3.1% to +2.1% in concave surface. In comparison of criteria from AAPM and IAEA reports, and statistical analysis for these results, it is found that the AAA's results are in good agreement with measured values and the M-Batho's results are generally good agreed with measured values among PBC algorithms.

• Applied Chemistry for Engineering
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• v.16 no.2
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• pp.257-261
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• 2005

The microbial cellulose is in a form of three dimensional net structures that consists of 20~50 nm fibrils. It possesses high crystallinity and orientation. It is difficult to synthesize large amount of fibrous carbon nanomaterials by the carbonization process using raw materials such as polyacrylonitrile (PAN), regenerated cellulose (Rayon) and pitch. However, it seems possible thru the application of microbial cellulose as raw material. The application of such cellulose can be further extended to the synthesis of highly oriented graphite fiber. Out of three different cellulose-producing strains, G. xylinus ATCC11142 was chosen as it has the highest productivity (0.066 g dried cellulose/15 mL medium). Tar is often produced during the carbonization of cellulose that limits the formation fibrous structure of the carbonized sample. In order to solve such a problem, pre-studied purification methods of carbon nanotube such as liquid phase oxidation, gas phase oxidation and filtration associated with ultrasonication were applied at the carbonized cellulose. In that case. only by filtration associated with ultrasonication, improved the formation of fiber structure of the carbonized cellulose.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.4
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• pp.477-481
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• 1998

Colored components in black tea were extracted, freeze-dried, and analysed to investigate the possibility using as a natural dye. Fractionation of the colored components was carried out by gel permeation chromatography. The colored components in black tea were elected into seven fractions. Each fraction was analyzed by UV spectrophotometer. The early fluted fractions 1-4 did not show any absorption peaks in 320-700 nm and showed the increase in absorption as it approaches to short wavelength and are considered as highly polymerized colored substances. Fractions 5-6 showed tar at 350 m and are considered as thearubigins. Fraction 7 showed absorption peaks at 376 nm and 456 nm and is considered as theaflavin. IR spectra of each fraction show: Strong C=0 stretching band at 1650 cm-1 appears in fractions 1-4, but not in fractions 5-7. Strong C=0 stretching band at 1700 cm-L appears in fraction 3-7. C=0 stretching band at 1610 cm-1 appears as a shoulder in fraction 4 and progressively changes into strong peak in fraction 5-7. From these results, it is assumed that colored components in black tea consist of polyphenolic substances having different molecular weight which were formed during tea manufacturing process. The colorants from black tea infusion were applied to silk, wool, cotton and nylon fabrics. Black tea colorants showed high affinity to wool, silk and nylon, but very low affinity to cotton fabrics.

• Carbon letters
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• v.3 no.1
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• pp.13-16
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• 2002

The modification of coal-tar pitch has been carried out by heat treatment of pitch at different temperatures in the range ($300^{\circ}-400^{\circ}C$) for different times (2-5 hrs) in air and nitrogen. The pitch heat treated in air at lower temperature ($300^{\circ}C$) exhibit increase in softening point by $20^{\circ}C$ as compared to only $2^{\circ}C$ when treated in nitrogen. The changes are faster in air than in pure nitrogen. Pitch as such as well as after heat treatment were further treated with metal complexes by solution route. Silver intake has been found to increase from 0.5 to 0.8 % in nitrogen treated pitch while the uptake is found to decrease for pitches treated in air at $350^{\circ}C$ for 5 hrs. Experiments have also been made to incorporate silver into PAN and PAN-ox fibers through solution route. The metal intake has been found to be more in PAN-ox fibers than in PAN as such. Metal loaded carbon composites have been made by using metal loaded fibers as well as cokes. These composites as such exhibit higher surface oxygen complexes but decrease after activation.

• Journal of environmental and Sanitary engineering
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• v.13 no.3
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• pp.102-112
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• 1998

The fate of polynuclear aromatic hydrocarbons(PAMs) in soil has drawn increasing concern due to their toxic, carcinogenic, and mutagenic effects. These compounds have been most commonly carried into the soil in solvent, as in a coal tar or cresote. This study has been focused on the applicability of microwave treatment of soils contaminated by PAHs. Studies have been conducted with soil(particle diameter $150~500{\mu}m$), which was spiked with naphthalene, acenaphthene, fluorene, anthracene and pyrene, with different moisture contents. According to the results of the research, up to 95% removal efficiency of naphthalene was observed in 10% moisturized soil for five minutes microwave inducing And the removal efficiency of acenaphthene and fluorene were observed to be 88.9%, 67.2% in 30% moisturized soil, respectively. Due to the low vapor pressure, anthracene and pyrene showed the low removal efficiency. In case the powdered activated carbon was added to the soil as a sensitizer, anthracene and pyrene were decomposed into a various by-products. Decomposition rates of anthracene and pyrene were increased with incresing addition of a PAC to the soil. It is concluded that the developement of a microwave process to remediate soils contaminated with PAHs is foreseeable. But additional studies are also needed regarding continuous microwave heating process.

• Korean Journal of Acupuncture
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• v.25 no.3
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• pp.147-166
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• 2008

Objectives : Crohn's disease (CD) is characterized by a chronic relapsing inflammation of the bowel in which proinflammatory cytokines play an important perpetuating role. Methods : Mice (preventive animal model of gliotoxin) were treated with 5 % 2,4,6-trinitrobenzenesulfonic acid (TNBS) at day 1 and day 7. To investigate preventive effects of acupuncture with Gujin at $LI_{11}$, acupuncture was carried out at day -1, day 1, day 3. And, to investigate therapeutic effects, acupuncture with Gujin was carried out at day 3, day 5, day 7. For the data analysis, we checked weight and width of colon, diarrhea, edema, survival rate, changes of body weight, and myeloperoxygenase (MPO) activity. For analysing protein expression, we carried out immunohistochemical staining and Western blot and we analyzed mRNA expression by RT-PCR. Results : Colon of TNBS treated mice was erosive and shortening compared with the colon of control mice and induced damages of colon epithelial cell layer and induced infiltration of immune cells in all layer of colon. Acupuncture of gujin at $LI_{11}$ in preventive mode suppressed macorscopic damages such as erosive and shortening of colon by TNBS and damages of intestinal epithelial cells and infiltration of immune cells in the colon. The average weight of 5 cm distal colon was increased in TNBS treated mice (758${\mu}g$) compared with in control mice (112${\mu}g$) and width of distal colon was also increased in TNBS treated mice (4.9mm) compared with in control mice (1.3mm). Acupuncture with Gujin at $LI_{11}$ in preventive and therapeutic mode suppressed increase of colon weight and width by TNBS. TNBS induced edema of colon and diarrhea and Acupunctured with Gujin at $LI_{11}$ in preventive and therapeutic mode ameliorated these symptom by TNBS. In preventive and therapeutic mode, the effects of acupuncture with Gujin at $LI_{11}$ were increasing the motility, suppressing body weight decreasing, suppressing MPO activity, reducing expressing of TNF-${\alpha}$, IL-1b, and ICAM-1 in colon compared with that by TNBS Conclusions : This study demonstrates that acupuncture with Gujin at $LI_{11}$ represents a potential therapeutic method of Crohn's disease.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.251-256
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• 2002

Fresh bamboo (Phyllostachys bambuoides sieb. et zucc.) was charred at the mechanical steel kiln and traditional earth kiln with subsequent condensation of its smoke to 10$0^{\circ}C$. It was settled down for 12 months to remove tar components and then the middle layer of the liquid was collected as a bamboo smoke distillates to analyze its chemical composition and physicochemical characteristics for use as food additives or processing aids. The gravity, transmittance, reflectivity, and viscosity were 1.008, 89.05%, 1.36%, and 12.48 cp in the bamboo smoke distillates processed by mechanical steel kiln (MBSD) and 1.012, 98.33%, 1.34% and 9.05 cp in the bamboo smoke distillates by traditional earth kiln (TBSD), respectively. The color of TSBD was brighter than that of MBSD. The pH and titratable acidity, tar and remains were 3.55 and 2.830%, 2.803% and 0.671%, respectively, in the MBSD and 2.93 and 3.470%, 0.051% and 0.004%, respectively, in the TBSD. The major phenolic compounds of bamboo smoke distillates (BSD) were phenol, Ο-cresol, p-cresol, and guaiacol and the major organic acids were acetic acid, propionic acid, iso-butyric acid, and n-butyric acid, and major alcohols were methanol, furfuryl alcohol, and maltol. The contents of phenolic compound and alcohol were more in MBSD than in TBSD whereas the content of organic acid was more in TBSD than in MBSD. Therefore, toxic compounds for the human body, such as methanol from BSD should be removed for use as a food ingredient in the future.