• 대한기계학회논문집B
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• 제28권12호
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• pp.1467-1474
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• 2004

Recently, with respect to an increase of energy consumption, many countries have tried to develop alternative fuels. In the United States, less than 10 percent of motor fuels will be displaced by alternative fuels by year 2010, with about 25 percent of the replacement fuels from renewable resources. But the level of exhaust gas is not decreased to the result of an increase of diesel vehicles. Moreover, emission regulations are being intensified by advanced countries such as America and Europe. Because Biodiesel is similar to diesel fuel, it is essential to judge the environmental and health effects deriving from the use of Biodiesel in diesel engine. Therefore, this research could be conformed whether both Biodiesel 20% and Biodiesel 100% are influenced on emission according to sulfur contents by applying DOC. As a result of using the Biodiesel, this research could be conformed though Nox was increased, CO, HC and PM were decreased, and also estimated to compare diesel fuel with the Biodiesel in accordance with engine performance and emission characteristics.

• Food Science and Biotechnology
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• 제18권1호
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• pp.66-72
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• 2009

An aqueous ribose-cysteine model system (initial pH 5.6) was conventionally heated to the same browning at varying temperatures ($120-180^{\circ}C$), supercritical carbon dioxide (SC-$CO_2$, 20 MPa) was also applied on the same matrices for same periods at each temperature and about 20% reduction of the absorbance at 420 nm was observed as compared with sole thermal treatment. The headspace volatiles from Maillard reaction mixtures were analyzed by solid-phase microextraction (SPME) in combination with gas chromatography and mass spectrometry (GC-MS), and predominated with sulfur containing compounds, such as thienothiophenes, polysulfur alicyclics, thiols, and disulfides. Reaction temperature exhibited complex effects on volatiles formation and those effects became further complicated by the SC-$CO_2$ treatment. The formation of noncarbonyl polysulfur heterocyclic compounds and thienothiophenes was generally favored at high temperatures. Most volatiles were inhibited in SC-$CO_2$ as compared with thermal treatment alone, however, the well-known meaty aromatic compounds, such as thiols and disulfides, were obviously enhanced.

• 한국수소및신에너지학회논문집
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• 제13권3호
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• pp.249-258
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• 2002

Thermochemical water-splitting IS(Iodine-Sulfur) process has been investigating for large-scale hydrogen production. For the construction of an efficient process scheme, two kinds of membrane technologies are under investigating to improve the hydrogen producing HI decomposition step. One is a concentration of HI in quasi-azeotropic HIx ($HI-H_2O-I_2$) solution by elecro-electrodialysis. It was confirmed that HI concentrated from the $HI-H_2O-I_2$ solution with a molar ratio of 1:5:1 at $80^{\circ}C$. The other is a membrane reactor to enhance the one-pass conversion of thermal decomposition reaction of gaseous hydrogen iodide (HI). It was found from the simulation study that the conversion of over 0.9 would be attainable using the membrane reactor using the gas permeation properties of the prepared silica hydrogen permselective membrane by chemical vapor deposition (CVD). Design criterion of the membrane reactor was also discussed.

• 한국식품영양과학회지
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• 제21권6호
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• pp.719-724
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• 1992

한국산 멸치젓의 휘발성 성분을 SDE/GC/MSD로 분석한 결과 총 73개의 화합물이 검출되었으며 aldehyde류(17종), ketone류(10종), alcohol류(12종), N-함유 화합물류(8종), ester류(7종), S-함유 화합물류(5종), furan류(5종) 및 alkane류를 포함한 9종의 기타화합물로 구성되어 있었다. 이중 58종의 화합물은 표준품과의 Rl로서 동정되었으며 나머지는 database에 의한 PBM search로서 잠정적으로 동정되었다. 함량면에서는 aldehyde류가 가장 많았고 다으으로 alcohol류, furan류, ester류, ketone류 순이였다. 특히 3-methylbutanal, 1-penten-3-ol, ehtylacetate, 2-ethylfuran 등의 화합물의 함량이 많았다.

• Journal of Plant Biology
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• 제16권1_2호
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• pp.17-22
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• 1973

The experiments were conducted to examine the injuries of $SO_2$, $NH_3$, and $SO_2$ and NH3 mixed gas to the germination and the growth of plants. Six kinds of plants were used as the material. These plants seeds were treated with the gases for five days. Rate of the germination and the growth in height of varying plants were different according to the components of the gases. The critical concentration of the gases for both the germination and the growth were in 5ppm of $SO_2$, 50ppm of $NH_3$, and 50ppm $SO_2$ and 50ppm $NH_3$ mixed gases. When a low concentration of $SO_2$ was treated together with NH3, especially it was reduced to 60 percent of the damage in the germination and the growth. In the treatemnt with $SO_2$, the germination of the seeds which soaked in water for 24 hours reduced the injuries more 40 percent than those which for one hour. It was observed that the seeds with thick coasts or with originally intact coats were suffered but little damaged by the gases, and the external symptoms of an injury were shown, at first, in water pore, and then, in guard cell on the leaves.

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3583-3587
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• 2010

Furoxanthiols PFT and BPFT possessing thiomethyl or thiobenzyl groups in the furoxan ring were designed and synthesized as potential light-sensitive alkyne precursors on a gold surface. The synthesis of thiofuroxans PFT and BPFT was performed from the corresponding halofuroxans 1b and 2c, respectively, by the substitution with potassium thioacetate in ethyl acetate/ethanol or DMF, followed by basic hydrolysis as the key reactions. Electron-beammediated fragmentation of furoxans 1c and 2d in a mass spectrometer afforded the corresponding aryl alkyne fragments, with the evolution of NO in high preference. In the cases of thiofuroxans PFT and BPFT, carbon-sulfur bond cleavage was observed as a representative fragmentation, producing M-SH and M-SAc peaks, which competed with the release of NO. In the fragmentation of mono-aryl furoxan 1c, the release of molecule of NO was predominately observed to produce an M-NO fragment as a base peak by the formation of trimembered thiiranium or azirine intermediate.

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권3호
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• pp.737-748
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• 2014

Increasing amounts of ships exhaust gases emitted worldwide forced the International Maritime Organization to issue some restricted maritime legislation for reducing the adverse environmental impacts arising from such emissions. Consequently, ships emission reduction became one of the technical and economical challenges that facing the ships, operators. The present paper addresses the different strategies that can be used to reduce those emissions, especially nitrogen oxides and sulfur oxides. The strategies included: applying reduction technologies onboard, using of alternative fuels, and follows one of fuel saving strategies. Using of selective catalytic reduction and sea water scrubbing appeared as the best reduction technologies onboard ships. Moreover, among the various proposed alternative fuels, natural gas, in its liquid state; has the priority to be used instead of conventional fuels. Applying one of those strategies is the matter of ship type and working area. As a numerical example, the proposed methods were investigated at a high-speed craft operating in the Red Sea area between Egypt and the Kingdom of Saudi Arabia. The results obtained are very satisfactory from the point of view of environment and economic issues, and reflected the importance of applying those strategies.

• 약학회지
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• 제13권4호
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• pp.101-110
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• 1969

The isozyme alteration of lactic dehydrogenase in the tissues of albino rat inhaled SO$_{2}$ were studied in vivo and in vitro, with the following results: (1) The H-type of LDH activity relatively dominated in the normal brain, heart and kidney tissues of rat, M-type in the normal lung, liver, and muscle tissues of the animal. (2) When rats inhale SO$_{2}$ in the concentration of 250 ppm, it appears that the M-type tends to predominate in the anaerobic tissues such as liver, kidney and muscle tissues and the H-type in the aerobic tissues such as brain and heart tissues. (3) When 5% SO$_{2}$ is introduced into tissue homogenates, LDH activities in the heart, lung, liver and muscle tissues are increased more than that of introducing room-air only. With sam treatment, LDH activity is decreased in the kidney tissue and no alteration is observed in the brain tissue. (4) Although, after the aeration of SO$_{2}$, the oxygen tension seems to bring decreases in the level of LDH activity in the anerobic tissues such as liver and muscle tissues, while, on the other hand, increases in the level of the activity in the aerobic tissues, such as the brain, heart and lung tissues. (5) Accordinglly, SO$_{2}$ affects LDH activities, its isozyme pattern of each organs, and their metabolic pathway by its absorption of the gas.

• 한국표면공학회지
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• 제45권2호
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• pp.61-69
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• 2012

Alloys of Fe-(5, 10, 15)Al and Fe-(10, 20, 30, 40)Cr were corroded at 700 and $800^{\circ}C$ for 70 hr in either atmospheric air or 1 atm of Ar+$1%SO_2$ gases. In these atmospheres, Fe-5Al and Fe-10Cr alloys displayed poor corrosion resistance. In atmospheric air, Fe-5Al alloys formed oxide nodules, while Fe-10Cr alloys formed thick scales and internal oxides. In Ar+$1%SO_2$ gases, Fe-5Al and Fe-10Cr alloys formed thick, nonadherent bi-layered scales, which grew primarily by the outward diffusion of Fe ions and inward diffusion of oxygen and sulfur ions. By contrast, in atmospheric air and Ar+$1%SO_2$ gases, Fe-(10, 15)Al and Fe-(20, 30, 40)Cr alloys displayed good corrosion resistance by forming $Al_2O_3$ and $Cr_2O_3$ layers on the surface, respectively.

• 열처리공학회지
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• 제22권4호
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• pp.210-216
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• 2009

Stainless steel EGR cooler of diesel engine is widely used to prevent the corrosion due to the content of sulfur in diesel fuel. The strength of brazed joint between stainless steel materials is very important. It is essential to observe the spreading ratio of the filler metals under the condition of deoxidation or vacuum during heating process. In this experiment, spreading ratio was tested to find the optimum brazing condition for stainless steel using brazing filler metals of FP-613, BNi-2 and BNi-5 on sus304 and sus410. Anti-corrosion tests were also performed on the above filler metals with solution of 5% $H_2SO_4$, 65% $HNO_3$ and 5% $NH_4OH$. Consequently FP-613 has good ability for anti-corrosion with 30% of chromium content compared with other filler metals. The optimum brazing conditions are occurred at $960^{\circ}C$ for 90 min. and at $1090^{\circ}C$ for 50 min. at the same degree of vacuum, $2{\sim}3{\times}10^{-3}$ Torr.