• 제목/요약/키워드: solubility

검색결과 3,019건 처리시간 0.029초

Properties of Biodegradable Films Produced from Rice Bran and Roasted Sesame Meal through Chemical Modifications

  • Bae, Dongho;Kim, Woo Jung;Jang, In Sook
    • Journal of Applied Biological Chemistry
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    • 제43권2호
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    • pp.79-85
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    • 2000
  • Biodegradable films were prepared from roasted sesame meal and rice bran. Acetic anhydride, succinic anhydride, and formaldehyde were added to the film-forming solutions, and their effects on tensile strength, percent elongation, water vapor permeability, and water solubility of the films were studied. Roasted sesame meal did not form film without acylation or addition of formaldehyde. Acylated roasted sesame films had higher tensile strength and water-solubility, and lower % elongation than rice bran films. Acylation with acetic and succinic anhydrides increased tensile strength, percent elongation, and water solubility of rice bran films, but decreased water vapor permeability. Treatment with formaldehyde increased tensile strength of roasted sesame and rice bran films and % elongation of rice bran films, while reducing water-solubility of roasted sesame and rice bran films and water vapor permeability of rice bran films.

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스테인레스강중의 Ti첨가에 따른 질소용해도 측정 (Measurement of Nitrogen Solubility with Ti addition in Stainless Steel)

  • 이영욱
    • 한국산학기술학회논문지
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    • 제10권11호
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    • pp.3043-3047
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    • 2009
  • 액상의 304스테인레스강중의 질소용해도와 질화물 형성관계를 시료채취법을 이용하여 측정하였으며, 이를 열역학적 함수로 규명하였다. 용융 304스테인레스강의 온도가 높을수록 질소용해도는 증가하였으며, 스테인레스강은 1기압의 질소 분위기하에서 0.3wt.% 이상의 Ti 첨가시 Ti계 질화물이 형성되었다. 또한 스테인레스강중에 Ti 첨가로 형성된 질화물은 TiN으로 판명되었다.

Solubilization of Oleanolic Acid and Urolic Acid by Cosolvency

  • Jin, In-Jung;Ko, Young-Ill;Kim, Young-Mi;Han, Suk-Kyu
    • Archives of Pharmacal Research
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    • 제20권3호
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    • pp.269-274
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    • 1997
  • Solubilities of oleanolic acid and ursolic acid in aqueous surfactant solutions, liquid polyethylene glycols (PEG), and solvents of various polarity were measured. The results showed that the solutes were slightly or moderately solubilized in the surfactant solutions and the liquid PEGS. It was also revealed that the solutes were slightly soluble in the solvent of either extreme polarity or nonpolarity, but moderately soluble in solvents of intermediate polarity of which solubility parameters are around 10. The solubility parameters of these solutes were calculated from the group contribution to be 10.2 for both of them. Of the solvents tested, tetramethylurea was exceptionally effective in solubilizing the solutes. The solutes were also moderately soluble in the aqueous cosolvents containing tetramethylurea. This suggests that the mixed systems of tetramethylurea could be employed for the solubilization in the formulation of these compounds as an aqueous system.

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A Study on the Desorption Behaviors of Some Heavy Metals on Duolite GT-73 Chelating Resin

  • Kim, Sook-Young;Lee, Jae-Suk;Kim, Young-Man;Choi, Beom-Suk
    • 분석과학
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    • 제14권6호
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    • pp.530-534
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    • 2001
  • Effect of stripping solutions on the Duolite GT-73 chelating resin for ten elements, Ag(I), Al(III), Ca(II), Cd(II), Cu(II), Fe(II), Hg(II), Mn(II), Pb(II), and Zn(II), was investigated. Relation between affinities of the metal ions and solubility products of metal sulfides was studied. The smaller the solubility product of metal sulfideis, the larger the affinitie with the ionsis. The ions which have the solubility products larger than $10^{-23}$ could be effectively desorbed with nitric acid. Complexation with chloride ion enhanced the desorption efficiencies of the ions having moderately strong affinity with the resin. The ions which have very strong affinity by the chelating resin can be desorbed by complextion with thiourea and hydrochloric acid.

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Facile Synthesis and Characterization of Poly(dialkoxy-p-phenylene 1,3,4-oxadiazole-alt-phenylene 1,3,4-oxadiazole)s

  • Kim, Hoon-Seok;Kang, Soon-Min;Do, Jung-Yun
    • Macromolecular Research
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    • 제16권4호
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    • pp.360-366
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    • 2008
  • Poly(dialkoxyphenylene 1,3,4-oxadiazole)s were conveniently synthesized to compare their material properties of solvent solubility, thermal stability and molecular alignment with respect to alkyl chain length and meta/para-phenylene structure. All prepared polymers exhibited good solubility in co-solvents containing various volume levels of chloroform to trifluoroacetic acid. Meta-polymers showed slightly better solubility than para-polymers. All polymers produced were thermally stable up to $320^{\circ}C$. Photoluminescence of polymer films was observed with blue light emission at around 450 nm. X-ray diffraction patterns of all polymers indicated that they were composed of stacked molecular sheets with the same layer-to-layer distance of $3.4\;{\AA}$. However, side chain-to-side chain and main chain-to-main distances within the layers increased with increasing alkyl chain lengths. The meta-polymer chains were separated more than the para-polymer chains.

Dissolution Characteristics of Copper Oxide in Gas-liquid Hybrid Atmospheric Pressure Plasma Reactor Using Organic Acid Solution

  • Kwon, Heoung Su;Lee, Won Gyu
    • 공업화학
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    • 제33권2호
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    • pp.229-233
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    • 2022
  • In this study, a gas-liquid hybrid atmospheric pressure plasma reactor of the dielectric barrier discharge method was fabricated and characterized. The solubility of copper oxide in the organic acid solution was increased when argon having a larger atomic weight than helium was used during plasma discharge. There was no significant effect of mixing organic acid solutions under plasma discharge treatment on the variation of copper oxide's solubility. As the applied voltage for plasma discharge and the concentration of the organic acid solution increased, the dissolution and removal power of the copper oxide layer increased. Solubility of copper oxide was more affected by the concentration in organic acid solution rather than the variation of plasma applied voltage. The usefulness of hybrid plasma reactor for the surface cleaning process was confirmed.

휴믹산에 의한 유기 염소계 농약의 수중 용해도 증가에 중금속이 미치는 영향에 관한 연구 (Effect of heavy metal on the solubility enhancement of organochlorine pesticides by humic acids)

  • 조현희;강소영;권효진;박재우
    • 한국토양환경학회지
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    • 제5권3호
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    • pp.55-64
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    • 2001
  • 많은 유기 염소계 농약들은 환경에서 매우 지속적이며, 먹이 사슬을 통해서 중요하게 생물학적으로 농축하는 경향이 있다. 농업에 적용되는 농약은 지표수의 유출이나 지하수의 흐름을 통해서 사실상 수 계로 이동되어지기 때문에 수환경에 특히 많은 영향을 끼치게 된다. 이 논문의 연구 목적은 두 가지 다른 휴믹산에 의한 유기 염소계 농약인 lindane과 dieldrin의 수중 용해도 증가에 중금속인 납 이온이 미치는 영향에 대해 알아보고자 하는 것이다. 또한 유기 염소계 농약이 두 가지 혼합물로 존재할 때 각각의 용해도에 서로의 상호작용에 대해서도 연구해 보고자 하였다. 휴믹산에 의한 lindane의 용해도 증가 정도는 거의 일정하였지만, 이에 비해 휴믹산에 의한 dieldrin의 수중 용해도 증가는 훨씬 증가함을 보여주었다. 또한 수중에 휴믹산과 납이 공존하면 dieldrin의 용해도는 납이 존재하지 않을 때보다 더욱 감소하였다.

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초임계 이산화탄소를 이용한 Ibuprofen의 용해도 측정 (Solubility of Ibuprofen in Supercritical Carbon Dioxide)

  • 김영애;주준호;임종성;김화용;이윤우
    • 청정기술
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    • 제11권3호
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    • pp.147-152
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    • 2005
  • 초임계 이산화탄소에서의 이부프로펜의 용해도를 측정하였다. 이부프로펜의 용해도는 variable volume view cell이 장착되어있는 고압장치를 사용하여 cloud point를 관찰하는 방법으로 실험하였다. 온도의 범위는 35, 40, $45^{\circ}C$로 하였고 측정된 실험값은 Peng-Robinson equation of state로 모델링 하였다. 이부프로펜의 물리적 특성은 Lydersen, Ambrose 그리고 Joback의 group contribution method를 사용하여 구한 값을 사용하였고, 각각의 결과를 비교하였다. 이산화탄소는 이부프로펜에 대해 큰 용해력을 가진다는 것을 확인하였고, 150bar 부근에서 retrograde 현상이 일어남을 알 수 있었다. 또한 Lydersen의 group contribution method를 사용하여 얻어진 이부프로펜의 물리적 특성으로 PR-EOS와 함께 모델링 한 결과가 다른 method보다 실험값과 더 잘 일치함을 확인하였다. 결과적으로 이 실험을 통해 초임계 공정으로 이부프로펜의 미세입자화 시킬 경우 용질이 용매에 용해되어야 하는 rapid expansion of supercritical solution (RESS)방법이 적용될 수 있음을 확인하였다.

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시클로덱스트린류와의 복합체 형성에 의한 벤즈이미다졸계 구충 약물의 용해성 및 용출 증가 (Solubilization and Dissolution Enhancement of Benzimidazole Antnelmintic Drugs by Cyclodextrin Complexation)

  • 전인구;박인숙
    • 약학회지
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    • 제37권3호
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    • pp.216-227
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    • 1993
  • Complex formations of practically insoluble antelmintic drugs such as mebendazole (MBZ), albendazole (ABZ) and flubendazole (FBZ) with dimethyl-$\beta$-cyclodextrin (DM-$\beta$-CyD) and 2-hydroxypropyl-$\beta$-cyclodextrin (HP-$\beta$-CyD) together with $\alpha$-, $\beta$- and $\gamma$-cyclodextrins(CyDs) in duffered solutions were investigated by solubility method. $A_{L}$ type phase solubility diagrams were obtained in all cases except for the complexation (B$_{s}$, type) of FBZ with $\gamma$-CyD. The highest stability constants were obtained with DM-$\beta$-CyD, followed by $\alpha$-CyD > $\beta$-CyD > HP-$\beta$-CyD > $\gamma$-CyD for ABZ, and HP-$\beta$-CyD > $\gamma$-CyD > $\beta$-CyD > $\alpha$-CyD for FBZ at pH 1.2. On the other hand, solid dispersion systems of ABZ and FBZ with $\beta$- and DM-$\beta$-CyDs were prepared by solvent evaporation method and evaluated by dissolution, differential thermal analysis and powder x-ray diffractometry. The dissolution rates of ABZ- and FBZ-DM-$\beta$-CyD solid dispersions were much faster than those of drugs alone, corresponding physical mixtures and tablets on market both at pH 1.2 and 6.8. Although dissolution rates of all samples at pH 6.8 were by far lower than those obtained at pH 1.2, as explained by pH-solubility profiles for ABZ and FBZ, the dissolution rates at pH 6.8 of ABZ from $\beta$- and DM-$\beta$-CyD solid dispersions exceeded the respective equilibrium solubility (23.9 $\mu\textrm{g}$/ml). Fast dissolution of ABZ from solid dispersions with CyDs was attributed to the reduction of drug crystallinity and particle size which was supported by DTA and powder x-ray diffractometry. Consequently these results suggest that solid dispersion systems with CyDs may provide useful means to markedly enhance the solubility and dissolution of benzimidazole antelmintic drugs.

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사후 도체처리가 돈육 등심근의 근절길이와 육즙감량 및 단백질 용해성에 미치는 영향 (Effects of Carcass Treatments on Sarcomere Length, Drip Loss and Protein Solubility of Porcine Longissimus Muscle)

  • 강근호;이정일;주선태;박구부
    • 한국축산식품학회지
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    • 제21권3호
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    • pp.192-199
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    • 2001
  • The objective of this study was to investigate the effects of hot- and cold-boning on sarcomere length, drip loss and protein solubility of post-rigor porcine longissimus muscle. A total of ten pigs(borrow, 100$\pm$5 kg) were randomly selected at a commercial plant and the carcasses were split in half after slaughter. The longissimus muscle of the left side was dissected and chilled at 0$^{\circ}C$ after trimming of subcutaneous fat whereas the right side carcasses were served for cold-boning after chilling for 24 hrs. The temperature, pH and sarcomere length of porcine longissimus muscle were measured at postmortem 1, 3, 6, 12 and 24 hours. Drip loss, cooking loss, Minolta L*a*b*, shear force and protein solubility were measured at postmortem 24 hrs. The pH of cold-boning samples was rapidly decreased whereas temperature and sarcomere length of hot-boning samples were rapidly decreased during 24 hrs of chilling. Hot-boning muscles showed significantly (P<0.05) higher pHu and shorter sarcomere compared with cold boning muscles because of cold shortening. However, there were no significant differences in drip loss, cooking loss and shear force value between hot- and cold boned samples. The samples of hot-boning showed lower Minolta L* value and higher sarcoplasmic protein solubility compared with cold boned samples. These results suggest that the pale color changing of porcine longissimus muscle could be inhibited by hot-boning due to rapid chilling of the muscle although sarcomere length could be shortened because of cold shortening. Also these results show that hot-boning of porcine carcass could have a high protein solubility without negative effects of drip loss or tenderness of porcine longissimus muscle.

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