• 제목/요약/키워드: Phase solubility

검색결과 333건 처리시간 0.032초

초임계 유체를 이용한 고분자 합성 연구 (Synthesis of Polymers in Supercritical Carbon Dioxide)

  • 이현석;김진웅
    • 대한화장품학회지
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    • 제36권1호
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    • pp.17-32
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    • 2010
  • 본 총설에서는 이산화탄소에 용해력이 있는 새로운 탄화수소 공중합체의 설계와 개발, 그리고 생체친화성 고분자의 초임계 중합을 위한 효과적인 계면활성제로써의 성능에 대해 소개하고, 초입계 유체의 기본적 개념을 용매로서의 성질과 고분자 합성분야에서의 응용적인 측면에서 기술한다. 이산화탄소에 높은 용해력을 지닌 탄화수소 고분자 중합을 위해 새로운 리빙라디칼 중합기술을 사용하였고, 이 물질들의 이산화탄소 내에서의 상거동을 측정하여 공중합체의 분자량과 구조가 용해도에 미치는 영향을 조사하였다. 초임계 분산중합에서의 효과적인 계면활성력을 확인하였고, 성장하는 입자의 안정화에 필요한 키 파라미터를 결정하기 위해 다양한 조건에서 실험을 수행하였으며, 화장품 분야에 응용될 수 있는 새로운 구조의 친환경 고분자 소재 개발에 이 연구가 작용될 수 있다는 잠재적인 가능성을 확인하였다.

잉여슬러지를 이용한 저온 열적전처리 및 바이오 가스 특성 평가 (Evaluation of Low-temperature Thermal Pre-treatment and Biogas Characteristics using Waste Activated Sludge)

  • 최재훈;정성엽;김지태
    • 한국물환경학회지
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    • 제35권4호
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    • pp.299-307
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    • 2019
  • The purpose of this study was to investigate the effect of low temperature thermal pre-treatment on biodegradation of waste activated sludge for anaerobic digestion as a countermeasure for increasing sludge generation. The experimental condition was accomplished in 2 %, 4 %, and 6 % TS concentration, and $70^{\circ}C$, $80^{\circ}C$, $90^{\circ}C$ of temperature for a maximum of 120 minutes retention time. Then, it was followed by analysis of physical/chemical properties, BMP test and composition of biogas. The biogas characteristic was evaluated by applying the modified Gomperz model. As a result, solubility of dissolved substrate, such as $SCOD_{Cr}$, soluble carbohydrate, and soluble protein, and biogas production increased as temperature increased. Solubilization efficiency at $90^{\circ}C$ was 18.4 %, 17.03 % and 16.88% in 2 %, 4 %, and 6 % TS concentration respectively. Also, solubilization rates of carbohydrate and protein similarly increased. BMP test results also showed that methane production in excess sludge increased to 0.194, 0.187 and $0.182m^3/kg$ VS. respectively, and lag phase decreased to 0.145, 0.220, 0.351 day due to acceleration of the hydrolysis step. Consequently, low-temperature thermal pre-treatment could increase biodegradability of sludge, positively affecting biogas production and sludge reduction.

환경 독성 억제효과를 가진 커큐민 나노스피어가 마우스의 사료 효율 및 악취저감에 미치는 영향 (Effects of Anti-ecotoxicological Curcumin Nanospheres on Feed Efficiency and Fecal Odor in Mice)

  • 박정배;이영민;박문기;민태선;이세중
    • 한국환경과학회지
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    • 제28권2호
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    • pp.183-189
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    • 2019
  • Curcumin ($C_{21}H_{20}O_6$) is a hydrophobic polyphenol found in turmeric. Although curcumin has been used as a natural medicine, its major limitation is related to poor absorption from the gut. Therefore, we developed a method for preparation of Curcumin Nanospheres (CN) to improve the aqueous-phase solubility of curcumin and investigate the functional role of CN in promoting feed efficiency and odor reduction in mice. CN showed inhibitory effects on actate dehydrogenase (LDH) cytotoxicity induced by ecotoxic substance toluene in gut epithelial HCT116 cells. In addition, the weights of internal organs (liver, heart, kidneys, and spleen) and the levels of serum Glutamate Oxaloacetate Transaminase (GOT), Glutamate Pyruvate Transaminase (GPT), and LDH did not show significant differences between mice administered oral CN for two weeks and compared to the control group. Interestingly, CN not only reduced hydrogen sulfide ($H_2S$) and ammonia ($NH_3$) levels and fecal odor, but also improved feed efficiency in mice. These results demonstrate that oral nano-delivery of anti-ecotoxicological CN is a functional system to deliver curcumin to the gut to improve feed efficiency and reduce fecal odor in mice.

Effect of extraction conditions on the stability and safety of sericin

  • Ji Hae, Lee;Hyun-Bok, Kim;HaeYong, Kweon
    • International Journal of Industrial Entomology and Biomaterials
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    • 제45권2호
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    • pp.93-98
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    • 2022
  • To assess the feasibility of silk sericin for non-textile application, the storage stability and biological safety of sericin were examined. It was extracted at 37℃, 70℃, 100℃, and 121℃ for 1, 3, and 5 h to elucidate the effect of extraction condition on the stability and safety of silk sericin. The solubility was increased till approximately 26% with extraction temperature of 121℃ for 1 h. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that the molecular weight distribution depended on the extraction conditions. Extracted sericin displayed typical UV absorption bands upon spectrometric analysis. To examine the reproducibility of its obtained conformation, sericin was extracted thrice and its circular dichroism (CD) spectra was measured each time. Most CD spectra showed reproducibility regardless of temperature and time except under 100℃ extraction condition. The diversity of CD spectrum showed gradual reduction and was finally coincident with extraction time from 1 to 5 h. Notably, sericin has a negative peak of approximately 200 nm attributed to random coil conformation, regardless of extraction condition. However, at the 100℃ extraction condition, sericin showed both bands to be negative bands of approximately 200 and 220 nm, respectively. Sericin was centrifuged to determine the stability of storage conditions. The sericin extracted at 100℃ and 121℃ for 1 h was found to form gel rapidly within 1 h, but at 121℃ condition, the gel fraction was approximately 20% within 1 h which retained its phase regardless of storage time. The gel fraction of sericin extracted at 100℃ for 5 h increased with time, however at the 121℃ for 5 h condition, the gel fraction was measured to be less than 10% regardless of increase in storage time. PetriflimTM AC plates test showed that sericin was safe from aerobic bacteria activity by extraction under high temperature.

Observation of Mitotic Chromosome behavior according to Different Treatment Methods of DNA Methylation Inhibitor

  • Seong-Wook Kang;Ji-Yoon Han;Seong-Woo Cho
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2022년도 추계학술대회
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    • pp.221-221
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    • 2022
  • Chromosome breakage occurred by DNA methylation inhibitor. Zebularine is known as DNA methylation inhibitor and suitable for water solubility among different DNA methylation inhibitors as 5-Azacytidine and 5-aza-2'-deoxycytidine. We used zebularine as mutagen according to different methods by roots absorption and seed imbibition. After zebularine treatment, DNA methylation inhibitor, we observed mitotic chromosome behavior what is different according to two different treatment methods. First, seed imbibition treatment in 1,000 μM of zebularine solution for 72 hours in dark conditions. The second treatment to seedlings of Keumkang was also treated in 1,000 μM of zebularine solution for 72 hours after germination. Root and shoot showed different elongations in each treatment. Root absorption treatment(3.01±0.48, 2.00±0.26) showed the shortest elongation in root and shoot than control(8.16±0.61, 4.03±0.48) and seed imbibition treatment(4.33±0.80, 2.48±0.36). It can be explained root tip meristematic cell activity was damaged by DNA methylation inhibitor. Primary root tips were collected in DW for 24 hours at low temperature(0℃) and fixed in fixation solution for 3 days to chromosome observation in mitosis. Mitotic index, chromosome structure and chromosome aberration were observed by phase-contrast microscope. Mitotic index of the control(0.29) showed twice mitotic cells as the treated groups(imbibition 0.15, absorption 0.14). Observation of chromosomes showed some short chromosomes and loosen chromosomes affected by zebularine. It is considered because of zebularine damage DNA in mitosis. We observed "gap by chromosome breakage" in chromosomes that have loose parts between centromere and telomere. It seems demethylation of zebularine occurs chromosome breakage.

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초고속 원심방사에 의한 아세트산프로피온산 셀룰로오스/폴리부틸렌 숙시네이트 다공성 마이크론 섬유 제조 (Fabrication of Porous Cellulose Acetate Propionate/Polybutylene Succinate Microfibers by High Speed Centrifugal Spinning)

  • 김태영;김미경;김진수;이정언;정재훈;김영권;김태현;김기영;염정현
    • 한국염색가공학회지
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    • 제35권4호
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    • pp.239-245
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    • 2023
  • Cellulose is an abundant biodegradable material in nature with excellent properties, but due to its poor processability, it has been widely studied for processing through modification. Cellulose acetate propionate (CAP) is a cellulose derivative in which the hydroxyl group of cellulose is replaced by acetyl and propionyl groups. CAP has several advantages, such as excellent solubility, structural stability, light and weather resistance, and good transparency. Porous nanofibers with excellent specific surface area, which can be applied in various fields, can be easily formed by the phase separation method using highly volatile solvents. High speed centrifugal spinning is a nano/micro fiber preparation method with advantages such as fast spinning and easy alignment control. In this study, a CAP/polybutylene succinate (PBS) spinning solution with chloroform as solvent was prepared to prepare porous microfibers and the fiber morphology was examined as a function of the disk rotation speed in an high speed centrifugal spinning device.

어상천망간광산 모암의 지구화학 (Geochemistry of the Country Rock of Eosangcheon Manganese Deposit)

  • 이재영;황덕환
    • 자원환경지질
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    • 제17권1호
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    • pp.17-34
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    • 1984
  • 어상천 망간광상은 조선계 홍훨리층의 돌로마이트와 삼태산층의 석회암내에 발달한 단층 파쇄대를 따라 형성된 표성산화망간광상이다. 본 산화망간광상의 하부에는 백악기 석영반암에 의하여 형성된 열수교대 내지 충진광상이 본 단충파쇄대를 따라 발달한다. 석영반암은 주성분으로 부터 계산한 노음치를 Q-K-F-PI 삼각도에 점시하면 북서단은 화강섬록암의 영역에 그리고 주암체는 화강암의 영역에 점시되고 D.I.치는 상기 북서단에서 부터 주암체쪽으로 증가한다. 따라서 이것은 마그마의 분화작용과 관계되는 것으로 보인다. 본 석영반암내 암질의 차이는 미량성분에도 반영이 되어 나타나고 있는 데 북서단에서 아연, 닉켈, 크롬, 몰리브텐의 함량이 높고 주암체에서는 동, 연의 함량이 높은 현상은 산성암과 염기성암에서 일반적으로 볼 수 있는 함량의 변화와 일치한다. 경상분지내 백악기 화강암류와 비교해 보면 동, 연, 아연, 닉켈, 크롬의 함량은 석영반암쪽이 분지내 동광상구의 화강암류보다 낮으나 동과 닉켈의 함량은 연 아연 광상구의 화강암류보다도 높은 경향을 보인다. 석회암 및 돌로마이트로 구성된 모암은 석영반암에 의한 광화작용으로 단층파쇄대에서는 망간, 연, 아연, 동등의 함량이 현저히 높고 멀어짐에 따라 감소되는 일차후생분산형태를 보인다. 토양중 미량원소의 함량은 토양의 생성조건 및 물리화학적조건과 밀접한 관계를 보이며 모암에서의 그들이 형성하는 탄산염의 용해도와도 주목할만한 관계를 보인다. 즉 난용성의 탄산염을 형성하는 미량원소는 토양중의 함량도 낮은 경향을 보인다.

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Development of Self-microemulsifying Drug Delivery System for Enhancing the Bioavailability of Atorvastatin

  • Jin, Shun-Ji;Cho, Won-Kyung;Park, Hee-Jun;Cha, Kwang-Ho;Park, Jun-Sung;Koo, Ja-Seong;Wang, Hun-Sik;Kim, Jeong-Soo;Kim, Min-Soo;Hwang, Sung-Joo
    • Journal of Pharmaceutical Investigation
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    • 제41권2호
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    • pp.103-109
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    • 2011
  • The objective of the study was to prepare self-microeulsifying drug delivery system (SMEDDS) incorporating atorvastatin calcium and evaluate its properties and oral bioavailability. Solubility of atorvastatin in various vehicles was determined. Pseudo-ternary phase diagrams were constructed to identify the good self-emulsification region. The droplet size distributions of the resultant emulsions were determined by dynamic light scattering measurement. The mean droplet size of chosen formulation (20% ethyl oleate, 40% tween-80, 40% Carbitol$^{(R)}$) was $23.4{\pm}1.3$ nm. The SMEDDS incorporating atorvastatin calcium appeared to be associated with better performance in dissolution and pharmacokinetic studies, compared with raw atorvastatin calcium. In dissolution test, the release percentage of atorvastatin from SMEDDS mixture could rapidly reach more than 95% within 3 min. Oral $AUC_{0{\rightarrow}8hr}$ values in SD rats was $1994{\pm}335\;ng{\cdot}hr/mL$, which significantly increased (P<0.05) compared with raw atorvastatin calcium. The SMEDDS formulation was relatively stable when stored at $4^{\circ}C$ during 3 months. Our studies illustrated the potential use of SMEDDS for the delivery of hydrophobic compounds, such as atorvastatin, by the oral route.

소나무 수피 바이오차를 이용한 수중에서 망간의 제거능력 향상 (Enhancement of Manganese Removal Ability from Water Phase Using Biochar of Prinus densiflora Bark)

  • 김민지;최정훈;최태령;최석순;하정협;이영석
    • 공업화학
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    • 제31권5호
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    • pp.526-531
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    • 2020
  • 수중에 함유된 망간 이온은 인체에 독성 물질로 작용하며, 또한 신경계에 영향을 미치는 것으로 알려져 있다. 특히 망간은 넓은 pH 영역에서 높은 용해성으로 인하여, 망간 제거가 어렵기 때문에 이를 효과적으로 처리하는 연구가 필요하다. 본 연구에서 소나무 수피 바이오차를 과산화수소로 화학적으로 개질하였고, 개질된 흡착제는 수중에서의 망간 이온 제거에 사용되었다. 개질된 흡착제는 망간이온 5, 10 mg/L 조건에서 각각 82.1, 56.2%의 높은 제거능력을 나타내었다. 또한 망간 농도 변화에 의한 흡착 데이터로부터 이론식에 적용하여 분석하였다. 그 결과 망간 이온의 흡착 거동은 Freundlich 보다는 Langmuir 모델에 잘 부합하였으며 또한, 동력학적 고찰에 의하면 유사 2차 반응식(pseudo-second order kinetic model)이 더욱 적합함을 알 수 있었다. 그리고 Gibbs 자유에너지 변화에서는 흡착 반응의 온도가 증가할수록 자발성이 보다 더 잘 이루어진다는 것을 도출하였다. 결과적으로 이러한 실험 결과들은 수중에 함유된 망간 이온을 효과적으로 제거하는 수처리 기술로 사용될 수 있을 것이다.

Franz diffusion cell을 이용한 참당귀 추출물 함유한 로션제형의 피부 투과 연구 (A Study of the Transdermal Permeation of Lotion Formulations Containing Angelica gigas Nakai Extracts in Franz Diffusion Cells)

  • 김강민
    • 생명과학회지
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    • 제31권11호
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    • pp.1004-1009
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    • 2021
  • 참당귀는 여러가지 약리효과를 가지며 한약재로 많이 사용된다. 특히, 참당귀 추출물 중 데커신 및 데커시놀 안젤레이트는 의약품 및 화장품 원료로써 사용될 수 있다. 이번 연구의 목적은 참당귀 추출물을 이용하여 제조된 제형의 국소 전달 가능성을 조사하는 것이다. 국소 전달 로션 제형은 유상으로 테포오즈 및 파라핀을 사용하였고 계면활성제 또는 용해보조제로써 데커신 및 데커시놀 안젤레이트에 높은 용해(0.82 mg/ml)를 가졌던 콜리포어를 사용하고 수상으로 카보머를 사용하였다. 제조된 로션을 프란츠셀에서 Strat-M® 멤브레인을 이용하여 피부투과도를 측정하였다. 로션 제형의 데커신 및 데커시놀 안젤레이트의 24시간 투과도는 (248.08±19.72 ug/cm2)로 대조군 (119.18±19.23 ug/cm2) 보다 증가함을 확인하였다. 피부투과속도 Flux (ug/hr/cm2)와 침투 속도 Kp (cm/hr)값에서는 시험군은 17.20±1.23 ug/hr/cm2와 5.73±1.39 cm/hr*10-3로 대조군의 8.22±1.24 ug/hr/cm2과 2.74±0.51 cm/hr*10-3보다 약 2배 정도 증가함을 확인할 수 있었다. 결론적으로 제조된 로션 제형은 국소 적용 의약품 또는 화장품 제품으로의 가능성을 확인하였다.