• Bulletin of the Korean Chemical Society
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• 제27권5호
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• pp.783-785
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• 2006

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2005년도 수소연료전지공동심포지움 2005논문집
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• pp.313-316
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• 2005

• Bulletin of the Korean Chemical Society
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• 제9권6호
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• pp.402-403
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• 1988

• Bulletin of the Korean Chemical Society
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• 제22권4호
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• pp.349-350
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• 2001

• International Journal of Human Ecology
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• 제8권1호
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• pp.1-8
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• 2007

Degradation of cellulose during prolonged exposure in atmospheric conditions has been recognized as one of main problems in preserving cellulose-made products. The purpose of this research was therefore to study effects of borohydride reduction in improving both the color and strength retention of cotton fabrics artificially aged at temperatures ranging from $100^{\circ}C$ to $150^{\circ}C$. Results indicated that the fabrics treated with either sodium or tetramethylammonium borohydrides (TMA) were degraded at rates about one-half that of water-washed cotton. These results were consistent over the temperature range. Calculation of the activation energy (Ea) by different methods showed $Ea\;=\;25.5{\pm}\;1.5\;Kcal$, in keeping with measurements made by others at lower temperatures. The TMA-treatment was effective in minimizing discoloration of the fabrics with pre-baking, but not of the un-prebaked fabrics.

• 한국수소및신에너지학회논문집
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• 제31권5호
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• pp.444-452
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• 2020

This study investigated the cathode catalyst of direct borohydride/hydrogen peroxide fuel cells for space exploration. Various catalysts such as Au, Ag, and Ni were supported on multiwalled carbon nanotubes (MWCNTs). Various techniques, such as transmission electron microscopy, Brunauer-Emmett-Teller method, scanning electron microscopy, and X-ray diffraction were conducted to investigate the characteristics of the catalysts. Fuel cell tests were performed to evaluate the performance of the catalysts. Ag/MWCNTs exhibited better catalytic activity than the Ni/MWCNTs and better catalytic selectivity of the Au/MWCNTs. Ag/MWCNTs presented good catalytic activity and selectivity even at an elevated operating temperature. The performance of Ag/MWCNTs was also stable for up to 60 minutes.

• Bulletin of the Korean Chemical Society
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• 제16권7호
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• pp.625-630
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• 1995

α-Linked D-altropyranosidic derivatives were obtained by configurational change at C-3 of α-D-mannopyranosides as the key step in preparation of allyl and methyl α-D-glycopyranosides of 6-deoxy-D-altro-heptose. The manno-altro conversion was effected by sequential reactions of Swern oxidation and stereoselective borohydride reduction. Allyl 4,6-O-benzylidene-2-O-p-methoxybenzyl-α-D-mannopyranoside was transformed to the corresponding altropyranoside via 3-oxo-arabino-hexopyranoside. Allyl 7-O-benzyl-6-deoxy-3,4-O-isopropylidene-α-D-altro-heptopyranoside has been prepared as a glycosyl acceptor to be coupled with β-D-GlcpNAc-(1→3)-α-D-Galp glycosyl donor for the synthesis of an O-antigen repeating unit of Campylobacter jejuni serotypes O:23 and O:36. Stereoselective borohydride reduction also succeeded in yielding methyl 2,4,7-tri-O-benzyl-6-deoxy-α-D-altro-heptopyranoside from the corresponding 3-oxo-α-D-arabino-heptopyranoside. C-6 Homologation was achieved by sequential reactions of cyanide displacement of 6-sulphonates, reduction of the resulting heptopyranosidurononitrile with diisobutylaluminum hydride, hydrolysis of the imine, and further reduction with sodium borohydride.

• 한국산학기술학회논문지
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• 제13권7호
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• pp.3261-3266
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• 2012

수소발생 및 저장 물질로서 붕수소화나트륨($NaBH_4$)은 촉매 분해반응을 통하여 수소를 생성할 수 있는데, 이 프로타이드 화합물을 이용하여 가정용 또는 이동용 연료전지의 수소를 공급할 수 있어서, 이 화합물과 분해반응에 대한 연구가 많이 수행되고 있다. 본 연구에서는 알칼리성 $NaBH_4$ 수용액을 귀금속이 담지된 금속산화물 촉매를 이용하여 가수분해반응을 일으키고, 그 분해반응 산물인 수소의 발생량을 측정하였다. 지지체로 사용한 금속산화물의 종류를 비교하고, 함침된 귀금속으로서 백금과 루테늄을 비교하였으며, 촉매사용량, $NaBH_4$ 용액의 농도 등의 영향을 고찰하고, 수소 발생 패턴을 조사하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.319-319
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• 2011

Hydrolysis of sodium borohydride provides a safe and clean approach to hydrogen generation. Having the proper catalytic support for controlling this reaction is therefore a valuable technology. Here we demonstrate the capability of hydroxyapatite as a novel catalytic support material for hydrogen generation. Aside from being inexpensive and durable, we reveal that Ru ion exchange on the HAP surface provides a highly active support for sodium borohydride hydrolysis, exemplifying a high total turnover number of nearly 24,000 mol $H_2$/ mol Ru. Moreover, we observe that the RuHAP support exhibits a high catalytic lifetime of approximately one month upon repeated exposure to $NaBH_4$ solutions. In addition to examining surface area effects, we also identified the role of complex surface morphology in enhancing hydrolysis by the catalytic transition metal covered surface. Particularly, we found that a polycrystalline RuHAP catalytic support exhibits shorter induction times for the initial bubble formation as well as increased hydrogen generation rates as compared to a single crystal supports. The independent factor of a complex surface morphology is believed to provide enhanced sites for gas release during the initial stages of the reaction. By demonstrating the ability to shorten induction time and enhance catalytic activity through changes in surface morphology and Ru content, we find it feasible to further explore this catalyst support in the construction of a practical hydrogen generator.

• 한국수소및신에너지학회논문집
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• 제13권2호
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• pp.135-142
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• 2002

본 연구는 Chemical hydride 형태의 수소발생제를 포함한 액체연료를 이용한 신개념의 알칼라인 연료전지의 특성을 분석하였다. Chemical hydride는 연료전지의 수소공급원으로써 사용될 수 있으며, 본 연구팀은 KOH 전해질에 수소발생제인 Sodium Borohydride ($NaBH_4$)를 첨가하여 제조된 액체연료를 알칼라인 연료전지에 공급함으서 상온에서 매운 우수한 전기 화학적 성능결과를 얻을 수 있었다. 이때 음극 찰물질로 $ZrCr_{0.8}Ni_{1.2}$ 수소저장합금이 사용되었으며, 양극은 방수처리된 카본지 위에 분산된 Pt/C 가 사용되었고, air가 latm으로 양극에 공급되었다. 음극에 대한 XRD 분석결과 음극에서의 산화에 의해 Sodium Borohydride ($NaBH_4$)가 분해되어 수소가 발생되며, 연속적으로 액체연료가 주입되어도 전지가 작동하는 것을 확인할 수 있었다. 이때 에너지밀도는 6,000 Ah/kg (for $NaBH_4$ or $KBH_4$)이다.