• Transactions of the Korean hydrogen and new energy society
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• v.20 no.6
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• pp.519-525
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• 2009

The catalytic steam reforming of woody biomass tar and soot to convert a synthetic gas containing hydrogen was investigated by using a bench-scale biomass gasification system. One commercial nickel-based catalyst, Katalco 46-6Q, and two different kinds of natural minerals, dolomite and olivine, were tested as a reforming catalyst at various reforming temperatures. The reaction characteristics of woody biomass tar were also investigated by TGA at a variety of heating rates. With all three catalysts conversion efficiency of tar and soot increased at increasing temperature. The reforming of tar and soot in the synthetic gas induce the increase of combustible gases such as $H_2$, CO and $CH_4$ in the product gas. The nickel-based catalyst showed a higher tar and soot conversion efficiency than mineral catalysts under the same temperature conditions.

• Korean Journal of Acupuncture
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• v.25 no.2
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• pp.159-177
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• 2008

Objectives : Crohn's disease is a severe chronic inflammation that is treated mainly by immunosuppression, which often has serious side effects. There is need to develop new therapeutic methods or drugs that have few side effects in order to treat this disease. Acupuncture with Moxi-tar at Cheonchu (ST25) has anti-inflammatory properties, but the mechanism of its anti-inflammatory actions is unclear. We investigated the protective effects and speculated the mechanisms of acupuncture with Moxi-tar at ST25 on trinitrobenzene sulfonic acid (TNBS) induced colitis in mice which is a well known Crohn's disease animal model. Methods : 5 % TNBS was treated at day 1 and day 7 into rectum of mice. To investigate therapeutic effects of acupuncture with Moxi-tar at ST25, acupuncture was carried out on day 3, and day 6. For the data analysis, we observed macroscopic and microscopic findings of the colon. Weight and width of the colon, degree of damage, changes of body weight, and myeloperoxygenase (MPO) activity were checked. For analysing protein expression, we carried out immunohistochemical staining and Western blot. For analysing mRNA expression, RT-PCR was carried out. Results : TNBS induced damages on the colon of mice, while acupuncture of Moxi-tar at ST25 suppressed TNBS mediated damages similar to those on the colons of mice in the control (not treated with TNBS) group. The average body weight of TNBS treated mice (77.4%) was decreased compared with that of the control mice (105%), and acupuncture with Moxi-tar at ST25 suppressed the loss of body weight caused by TNBS (from 77.4% to 95.3%). TNBS induced infiltration of immune cells in all layers of the colon while acupuncture with Moxi-tar at ST25 suppressed infiltration of immune cells caused by TNBS. Furthermore, acupunctured with Moxi-tar at ST25 suppressed macro-, micro- colonic damages caused by TNBS. Acupunctured with Moxi-tar at ST25 dramatically improved the clinical and histopathological symptoms such as the increase in weight of the distal colon and the MPO activity in TNBS-induced colitis. Acupuncture with Moxi-tar at ST25 down-regulated the nuclear transcription factor kappa B ($NF-{\kappa}B$) activity and suppressed tumor necrosis factor-a (TNF-${\alpha}$), interleukin-$1{\beta}$ (IL-1${\beta}$), and intracellular adhesion molecule-1 (ICAM-1) expressions caused by TNBS. Conclusions : Acupuncture with Moxi-tar at ST25 helps recovery from the TNBS-induced colonic damage by down-regulation of $NF-{\kappa}B$ activity and suppressing of TNF-${\alpha}$, IL-1${\beta}$, and ICAM-1 expressions. This may be an important method for the treatment of Crohn's disease.

• Environmental and Resource Economics Review
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• v.17 no.4
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• pp.813-843
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• 2008

This paper investigates the presence of long-run and short-run price asymmetries in weekly gasoline prices from January 1997 to July 2008. In accordance with distribution channels, wholesale and retail stages are analyzed separately. An approach based on TAR and M-TAR cointegration tests, which entail matching asymmetric ECMs, is employed. For wholesale prices, asymmetries in the links with crude oil prices and exchange rates are found for both ECMs in the long-run and short-run. Exchange rates appear to play more significant role than crude oil prices in explaining the short-run price asymmetry. The rise in crude oil prices or exchange rates has statistically significant major impact on the increase of wholesale prices on the second week, not immediately as expected in the concept of 'rockets and feathers'. And asymmetrically, the fall does not have any statistically significant effect on the same period. The finding seems to be somewhat unusual. However, for retail prices, asymmetry m connection with wholesale prices is only revealed in the long-run. A symmetric price adjustment can be assumed in the short-run. Contrary to the long-run asymmetry found in the wholesale stage, in the retail stage, the speed of adjustment for negative deviations toward long-run equilibrium is faster than for positive ones, which is a phenomenon not favorable to consumers.

• The Journal of Traditional Korean Medicine
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• v.15 no.1
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• pp.113-127
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• 2006

Objectives: This study was produced to examine the effects of moxibustion that had been played important role to traditional oriental medical treatment on disease. Recently, it was reported that moxi-tar which is generated in the process of moxibustion as burning combustibles decreased nitric oxide(NO) and inducible NO synthase (iNOS) generation in cellular experiments. Methods: Carrageenan-induced arthritis rat model was used to test the effect of moxi-tar as a chronic pain model. Diluted moxi-tar was single injected in several acupoints or combined with electroacupuncture (l ms, 2 Hz, and 2 mA) into contralateral ST36 acupoint for 30 min to assess the synergic effects. After the treatment, behavioral tests measuring stepping force were periodically conducted during the next 12 hours. Endogenous NO and iNOS, cyclooxygenase-2 (COX-2), and c-Fos protein expression in the spinal cord were examined on a rat model of carrageenan-induced arthritis. Results : After the induction of arthritis, rats subsequently showed a reduced stepping force of the affected limb for at least the next 4 days. The reduced stepping force of the limb was presumably due to a painful knee, since oral injection of indomethacin produced temporary improvement of weight bearing. Maxi-tar produced significant improvement of stepping force of the hindlimb affected by the arthritis lasting at least 9 hours. The magnitude of this improvement was equivalent to that obtained after an oral injection of 3 mg/kg of indomethacin and this improvement of stepping force was interpreted as an analgesic effect. Maxi-tar produced the improvement of stepping force of the affected hindlimb in a dose-dependent manner. Both NO production and iNOS, COX-2 protein expression increased by arthritis were suppressed by maxi-tar. Moxi-tar on combination with electroacupuncture (EA) produced more powerful and longer lasting improvement of stepping force of the hindlimb affected by the arthritis than either moxi-tar or EA did. Conclusion : The present study suggest that maxi-tar produces a potent analgesic effect on the chronic knee arthritis pain model in the rat and that moxi-tar-induced analgesia modulate endogenous NO through the suppression of iNOS/COX-2 protein expression.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.267-270
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• 2014

Since contaminants of syngas obtained from the biomass gasification are removed, the syngas is clean fuel. In this study a high-efficiency energy production system is developed. The system produces electricity using a waste pressure and feeds a low-pressure steam to Dyeing industrial complex. Also, iron oxide derived from dyeing sludge is utilized as a self-catalyst to reform a tar and reduce a tar emission from gasifier. This system increases the amount of syngas and finally achieves a highly efficient gasification.

• The Korean Journal of Applied Statistics
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• v.24 no.1
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• pp.11-23
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• 2011

Robust unit root tests are developed for dynamic panels consisting of TAR processes. The test statistics are all based on diverse combinations of individual t-type tests for significance of TAR coefficients. Limiting null distributions are established. A Monte-Carlo experiment compares the proposed tests. The tests are applied to a panel data set of Canadian unemployment rates which show asymmetric features as well as having outliers.

• Journal of Acupuncture Research
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• v.21 no.3
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• pp.29-41
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• 2004

Objective : This study was produced to examine the effects of moxibustion that had been played important role to traditional oriental medical treatment on disease. Recently, it was reported that moxi-tar which is generated in the process of moxibustion as burning combustibles decreased NO and iNOS generation in C6-glioma and RAW 264.7 cells in our lab. Methods : C6-glioma cells were cultured in RPMI 1640 with FBS 10% in CO2 incubator. To study the protective effects of moxi-tar, we observed cell viability, DPPH activity, SOD activity, catalase activity and cell morphology after injury with $H_2O_2$. Results and Conclusions : Moxi-tar increased cell viability about twice as much as that of being injury by $H_2O_2$(moxi-tar $40{\mu}g/m{\ell}$, $H_2O_2$ $500{\mu}M$). And the results of free radical scavenger activity($80{\mu}g/m{\ell}$ : $78.91{\pm}4.4%$), SOD activity and catalase activity($80{\mu}g/m{\ell}$ : 21.6unit/mg protein) were increased by moxi-tar as dose-dependent manner. So we concluded that the effects of moxibustion which is played important role in Oriental medicine, might be free radical scavenger effects induced by moxi-tar. Conclusion : These results indicate that tBHP induces apoptosis through a lipid peroxidation-dependent mechanism and JS exerts the protective effect against the apoptosis by preventing peroxidation of membrane lipids.

• Journal of the Korean Wood Science and Technology
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• v.45 no.6
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• pp.772-786
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• 2017

This study investigated the characteristics of wood tar, produced as a byproduct during the production of charcoal using oak wood by the modified traditional kiln and mechanical steel kiln. The wood tar was analyzed with a number of techniques, including Py-GC/MS, NMR, MALDI-TOF, FT-IR, TG and DSC. The Py-GC/MS analysis indicated that modified traditional kiln generated a higher hydrocarbon ratio in the wood tar than that of mechanical steel kiln. On the other hand, mechanical steel kiln resulted in a higher proportion of phenolic and aromatic hydrocarbon components than that of modified traditional kiln. Those results were also confirmed by NMR analysis. The MALDI-TOF analysis suggested that the wood tar produced in the mechanical steel kiln had a slightly higher molecular weight than the wood tar produced in the modified traditional kiln. In addition, the FT-IR analysis showed characteristic peak of symmetrical stretching vibration of $CH_3$ from the modified traditional kiln while characteristic peaks of the C-C and C-O stretching vibration were observed from the mechanical steel kiln. Moreover, TG and DSC analysis suggested that the mechanical steel kiln is more thermally stable than that of modified traditional kiln. Those findings clearly showed that the method of making charcoal greatly affects the properties of wood tar.

• Journal of Korea Foresty Energy
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• v.24 no.1
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• pp.33-38
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• 2005

To find a new use of wood tar which is obtained from the manufacturing process of wood charcoal, a resol type of phenol adhesive using wood tar was made and some adhesion tests on plywood were examined. Phenol adhesive synthesized with pine tar was almost same as an original phenol adhesive in physical properties such as solid content and viscosity and tensile-shear adhesive strength of plywood made of phenol adhesive synthesized with pine tar was not much lower than the original one in non-waterproof and waterproof tests. Phenol adhesive synthesized with oak tar, however, was different from original phenol adhesive in physical properties. Adhesive strength of plywood made of oak tar was $50\%$ lower than the original one on waterproof tests. The amount of emitted formaldehyde increased as the amount of wood tar increased.

• Journal of Energy Engineering
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• v.2 no.2
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• pp.208-214
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• 1993

Pyrolysis of bituminous coal has been carried out in a two-stage fixed bed reactor to produce high heating value gas(7000 kcal/N㎥) for industrial or town gas usage. The effects of coke catalyst, pyrolysis temperature (468∼565$^{\circ}C$), and catalytic cracking temperature (700∼850$^{\circ}C$) on the product gas properties from pyrolysis of bituminous coal have been determined. From pyrolysis of Dong Jin coal with coke, the carbon deposition on catalyst is found to be less than 5% of product tar and approximately 15% of total energy iii the parent coal can be recovered as high heating value gas. Oil composition in the product tar from the two-stage pyrolysis is higher than that from low-temperature pyrolysis. The tar produced from pyrolysis below 516$^{\circ}C$ can be easily catalytically cracked but, the tar produced above 565$^{\circ}C$ cannot be cracked easily with catalyst. From the product gas analysis, the catalytic cracking temperature should be maintained below 800$^{\circ}C$ since cracking speed of ethylene increases remarkably with the cracking temperature above 800$^{\circ}C$.