• 한국수소및신에너지학회논문집
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• 제20권6호
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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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• 제25권2호
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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.

• 자원ㆍ환경경제연구
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• 제17권4호
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• pp.813-843
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• 2008

본 논문은 1997년 1월부터 2008년 7월까지의 주별 휘발유가격에 장기적 단기적 가격비대칭성이 존재하는지를 연구한다. 어떤 형태의 가격비대칭이 어느 단계에서 발생하는지 파악하기 위해 생산에서 소비에 이르는 과정을 도매단계와 소매단계로 분리해서 분석한다. TAR와 M-TAR 공적분모형과 거기에 대응하는 비대칭적 오차수정모형에 근거한 분석방법을 이용한다. 도매가격에 있어서는 원유가격 및 환율과 연관된 비대칭성이 두 형태의 오차수정모형에서 장기와 단기에 모두 발견된다. 단기적인 가격비대칭성을 설명하는데는 환율이 원유가격보다 더 중요한 역할을 하는 것으로 나타난다. '로켓과 깃털'에서 예상되는 대폭의 즉각적인 조정과는 달리 원유가격이나 환율의 상승은 도매가격의 인상 후 2주가 되어서야 통계적으로 유의한 주된 영향을 미친다. 그리고 특이하게도 비대칭적으로 원유가격이나 환율의 하락은 같은 기에 도매가격에 통계적으로 유의한 효과를 전혀 미치지 못한다. 소매가격에 있어서는 도매가격과 관련된 비대칭성이 오직 장기에서만 드러난다. 단기적으로는 대칭적으로 가격조정이 이루어진다고 할 수 있다. 도매단계에서 발견된 장기적 비대칭성과는 대조적으로 균형으로부터의 음(-)의 이탈이 양(+)의 이탈보다 장기적 균형 수준을 향해서 더 빠르게 조정되는데 이는 소비자에게는 불리한 현상으로 보인다. 국내 주별 휘발유가격 분석에서 TAR 과정 및 M-TAR 과정으로 나타낸 장기적 가격비대칭이 존재하는 것을 추정된 threshold를 이용해 확언한 것 그리고 장기 및 단기의 가격비대칭을 같은 모형에서 분석한 것은 본 연구가 처음으로 시도했다는 의미를 가진다.

• 한국전통의학지
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• 제15권1호
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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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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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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.

• 응용통계연구
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• 제24권1호
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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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• 제21권3호
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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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• 제45권6호
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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.

• 임산에너지
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• 제24권1호
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• pp.33-38
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• 2005

목탄의 제조과정에서 발생되는 목타르의 신용도를 찾고자 목타르를 이용한 레졸형 페놀수지접착제를 제조하여, 합판에 대한 접착력 시험을 실시하였다. 소나무타르계 접착제는 미첨가 페놀접착제와 비교했을 때, 고형분, 점도와 같은 수지의 물성은 유사하였으며, 인장 전단 접착력에서도 비내수, 내수 모두 페놀접착제에 비해 크게 떨어지지 않았다. 그러나, 참나무타르계 접착제의 경우에서는 수지물성도 페놀수지와는 다른 물성을 보였으며, 내수접착력은 페놀접착제의 접착력에 비해 절반 정도의 낮은 접착력을 보였다. 포름알데히드 방출량은 목타르의 첨가량이 많을수록 많이 방출되었다.

• 에너지공학
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• 제2권2호
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• pp.208-214
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• 1993

직접 연소시 다량의 공해물질이 배출되는 유연탄을 가공하여 산업용 및 도시가스로 활용이 가능한 고열량 가스(발열량 : 7000 kca1/N㎥)를 생산하기 위한 유연탄 가공 기술개발 연구의 일환으로 고정층 유연탄 이단 열분해 실험을 수행하였다. 본 연구에서는 코우크스 촉매를 사용하여 열분해온도를 468, 516, 5$65^{\circ}C$, 촉매분해온도를 700, 750, 800, 85$0^{\circ}C$로 변화시키면서 이단열분해 조건이 생성물의 특성에 미치는 영향을 조사하였다. 동진탄에 대하여 코우크스 촉매를 사용하여 이단 열분해 실험을 수행한 결과 촉매에 퇴적되는 탄소량은 생성 tar의 5% 이하였으며, 전체 석탄에너지중 15% 정도가 고열량 가스로 회수되는 것을 확인하였다. Tar 중에 포함된 oil성분의 양은 이단 열분해의 경우가 저온 열분해에서 보다 많이 생성되었으며, 열분해온도가 5$65^{\circ}C$ 인 경우 생성된 tar는 516$^{\circ}C$에서 생성된 tar보다 이단 열분해의 경우 촉매 분해가 잘 되지 않았다. 생성가스의 분석 견과는 촉매분해온도가 80$0^{\circ}C$ 이상이면 에틸렌의 분해속도가 급격히 증가하므로 80$0^{\circ}C$ 이하로 유지하는 것이 적절함을 보여준다.