• Macromolecular Research
• /
• 제15권5호
• /
• pp.424-429
• /
• 2007

A procedure for the surface hydrolysis of an electrospun poly(${\epsilon}$-caprolactone) (PCL) fibrous scaffold was developed to enhance the adhesion and proliferation of osteoblasts. The surface hydrolysis of fibrous scaffolds was performed using NaOH treatment for the formation of carboxyl groups on the fiber surfaces. The hydrolysis process did not induce deformation of the fibers, and the fibers retained their diameter. The cell seeding density on the NaOH-treated PCL fibrous scaffolds was more pronounced than on the non-treated PCL fibers used as a control. The alkaline phosphatase activity, osteocalcin and a mineralization assay strongly supported that the surface-hydrolyzed PCL fibrous scaffolds provided more favorable environments for the proliferation and functions of osteoblasts compared to the non-treated PCL fibrous scaffolds use as a control.

• 유기물자원화
• /
• 제29권4호
• /
• pp.99-106
• /
• 2021

본 연구는 혐기성 소화의 전처리로써 열가수분해와 고액분리가 결합된 공정의 성능을 평가하였다. 탈수케이크는 열가수분해를 통해 가용화되며, 이후 고액분리를 수행한다. 고액 분리된 액상은 혐기성 소화에 기질로써 이용되고 고형물은 열가수분해로 회수된다. 열가수분해의 가용화율(COD 기준)은 45.1-49.3%이며 고액분리와 결합한 공정은 76.1-77.6%로 나타났다. Dual-pool two-step model을 통해 도출된 메탄 발생 특성을 살펴보면 고액 분리된 액상의 전체 분해 가능한 물질 중 분해가 빠른 물질의 비(a)는 0.891-0.911로 열가수분해된 시료에 비해 높게 나타났다. 반면에 분해가 빠른 물질의 반응 속도(kF)는 유사하게 나타났다. 이를 통해 열가수분해와 고액분리가 결합한 공정은 열가수분해를 통해 분해가 빠른 물질을 생성하고, 고액분리를 통해 선별하는 것으로 나타났다.

• Korean Chemical Engineering Research
• /
• 제49권4호
• /
• pp.470-474
• /
• 2011

볏짚은 한국에서 매년 대량 생산되는 주요 작물이다. 침지공정을 이용한 목질계 바이오매스의 전처리는 대기압과 $60^{\circ}C$의 온도에서 온화한 조건에서 수행되었다. 본 연구에서는 전처리된 바이오매스의 효소당화 조건을 찾아보았다. 볏짚의 경우에 이전의 목질계 바이오매스와 비교하여 당화시간이 다른 것들보다 짧은 것으로 나타났다. SAA(Soaking in Aqueous Ammonia) 전처리 볏짚의 당화는 40~48시간 사이에 종료가 되었고 $50^{\circ}C$에서 높은 글루코스 전환율을 나타냈다. 글루코스 전환율은 효소사용량이 각각 65 FPU/ml과 32 CbU/ml일 때 높았다. 기질 농도가 5%(w/v)일 때 전환율은 72시간 동안 당화 후에 83.8%로 나타났다. SAA 전처리 볏짚의 동시당화발효(SSF; Simultaneous Saccharification and Fermentation) 실험에서는 $40^{\circ}C$에서 높은 에탄올 생산수율을 보였다. 그때의 수율은 48시간에서 33.05%로 나타났다.

• Korean Chemical Engineering Research
• /
• 제59권4호
• /
• pp.503-507
• /
• 2021

이동용 고분자전해질 연료전지(PEMFC)의 수소발생용으로써 NaBH₄는 많은 장점을 갖고 있다. 야외에서 PEMFC가 이송형으로 사용될 때 증류수대신 담수를 이용해 NaBH₄ 가수분해하면 경제적이다. 그래서 본 연구에서는 NaBH₄ 가수분해 과정에 증류수대신 담수를 이용해 수소를 발생시켰다. 활성탄 담지 Co-P-B/C 촉매를 사용해 NaBH₄ 가수분해 특성에 대해 연구하였다. 담수는 NaBH₄ 가수분해과정에서 4수화물을 발생시키지 않았고, 증류수는 4수화물 부산물이 생성되어 가수분해과정에서 많은 물이 소모되어서 NaBH₄ 25% 이상 고농도에서 반응 종료시점에는 건조한 부산물과 미반응 NaBH₄가 남았음을 확인하였다. 이 결과 담수를 사용했을 때 NaBH₄ 25% 이상 고농도에서 증류수보다 수소 수율과 수소발생속도가 더 높아 무인항공기등 이송형 연료전지에도 적용하기에 적합함을 보였다.

• 한국군사과학기술학회지
• /
• 제10권1호
• /
• pp.123-129
• /
• 2007

A 2-step process for the safe destruction of chemical wafare agents(agent hydrolysis followed by supercritical water oxidation) was studied to obtain kinetic data for the pilot plant design. This process is simple to operate by using commercial equipments and could be applied as an alternative technology to incineration. Sarin(GB) and sulfur mustard(HD) were hydrolysed in sodium hydroxide and water respectively and their hydrolysates and OPA, which is binary agent for GB were oxidized in a continuous flow supercritical water oxidation system. Destruction efficiencies of the materials were above 99.99% in supercritical water.

• 한국염색가공학회지
• /
• 제17권5호
• /
• pp.37-44
• /
• 2005

The electrolytic water(EW) has been used in agriculture, medical, semiconductor, and household fields. However there has been no use of EW in the textile process so far, because the application in the textile industry has been needed a large amount of EW in real process conditions. Recently, we have got electrolytic oxidation water(EOW) and electrolytic reduction water(ERW) by development of a electricity electron technology. And, the productivity of EW manufacture apparatus is arrived to large capacity. As a result, the application of EW could be possible in the textile industry. In this study, to confirm the possibility of application of EW, we scoured and hydrolyzed PET fabric using the EW. It was possible that the application of ERW for the scouring and hydrolysis of PET fabrics in the textile process.

• 한국막학회:학술대회논문집
• /
• 한국막학회 1996년도 추계 총회 및 학술발표회
• /
• pp.92-93
• /
• 1996

PVA membrane was widely used in the dehydration pervaporation process. PVA membrane showed remakable selectivity towed water and an excellent film-forming polymer, with a good resistance to orgamic solvents but it has poor stability in aqueous mixtures. Generally the PVA is manufactured by the hydrolysis reaction from poly vinyl acetate(PVAc) and so the degree of PVA hydrolysis is a major parameter for properties of PVA membrane such as the crystallinity and polarity.

• Biotechnology and Bioprocess Engineering:BBE
• /
• 제7권2호
• /
• pp.85-88
• /
• 2002

A study was carried out on the application of supercritical fluid to the hydrolysis of boll fibers of cotton (cultivar Tashkent-6 of Gossypium hirsutum L.) by cellulase enzymes from Trichoderma viride, Trichoderma reesei and Aspergillus niger. Conditions of the enzymatic process were optimized. The stabilities of cellulase enzymes were sustained at the pressure of up to 160 attn for 48 hours at 5$0^{\circ}C$ in supercritical carbon dioxide.

• 약학회지
• /
• 제25권1호
• /
• pp.37-42
• /
• 1981

Penicillin derivatives have a stability problem by hydrolysis of their .betha.-lactam ring. At high temperature, crystal water is released from penicillin derivatives, especially ampicillin trihydrate and concerns itself in hydrolysis. Penicillin derivatives having crystal water show different crystal states and different stability according to the variation of different condition on the process of manufacturing. The stability of ampicillin trihydrate in solid states was determined. Physico-pharmaceutical properties of this compound were determined by using IR spectra, X-ray powder diffraction and differential thermal analysis (DTA).

• Food Science and Biotechnology
• /
• 제16권3호
• /
• pp.381-385
• /
• 2007

The objective of this experiment was to study the influence of feed moisture content on the degree of enzymatic hydrolysis of com starch in a twin screw extruder and the saccharification yield of the dried extrudate. The feed moisture content was set at 25, 30, and 35% and ${\alpha}$-amylase solution was directly injected into the feed section at a barrel temperature of $95^{\circ}C$ and screw speed of 250 rpm. Amyloglucosidase was used for the saccharification of the dried extrudate at a concentration of 0.055%(w/w). Expansion ratio and swelling factor of extrudates decreased with increasing the feed moisture content. Addition of ${\alpha}$-amylase during extrusion process raised reducing sugar content of extrudates which also increased with the feed moisture content. The saccharification yield of dried extrudate was higher for the extrudate with lower feed moisture content.