• 제목/요약/키워드: inorganic component

검색결과 253건 처리시간 0.026초

고지재생연구(제 7보)-지료조성이 효소활성에 미치는 영향- (Recycling of Wastepaper(Ⅶ)-The Effect of Stock Composition on Enzyme Activity-)

  • 여성국;류정용;신종호;송봉근;오세균
    • 펄프종이기술
    • /
    • 제31권3호
    • /
    • pp.1-9
    • /
    • 1999
  • Effect of furnish on enzyme activity was investigated by using the three components (cellulose, enzyme, and cationic polyelectrolyte) model papermaking system. Avicel was used as a cellulose model compound to observe the effect of adsorption and desorption of enzyme with other component and the resultant change of particle size. As an experimental result, the enzyme loses considerably its apparent activity due to the adsorption onto cellulose and cationic polyelectrolyte. Activities of enzyme applied to the actual papermaking stocks having controlled fiber length showed different behavior in terms of pulp species UKP and KOCC stocks. That is, the enzyme activity in UKP was increased as fines content increased, however, vice versa in KOCC stock . This result can be considered to be the existence of various contaminants included in the fines of KOCC . The effect of possible contaminants such as inorganic materials, calcium ion, surfactant, and conductivity on enzyme activity were also investigated.

  • PDF

Mechanisms of gas permeation through microporous membranes - A review

  • Hwang, Sun-Tak
    • 한국막학회:학술대회논문집
    • /
    • 한국막학회 1995년도 제3회 심포지움 (분리막 연구의 최신동향)
    • /
    • pp.1-13
    • /
    • 1995
  • A review is presented for various gas tranport mechanisms through microporous membranes of both polymeric and inorganic materials. Different transport modes manifest depending on the pore size and the flow regime, which is a function of pressure, temperature, and the inateraction between gas molecules and the pore walls. For microporous membranes whose pores are small and the intenal surface area huge, the surface diffusion becomes a significant factor. If the pores become even smaller, them the transport mechanism will be more of an activated diffusion type. When conditions are right capillary condensation will take place to create an enormous capillary pressure gradient, which will greatly enhance the permeation flux. At the same time the capillary condensate of the heavier component may block the membrane pores denying the passage of the lighter gas molecules. All of these phenomena will influence the separation of mixtures.

  • PDF

Degradation of Properties and Loss of Nutrients in Gelatin Soft Capsules the Manufacturing Process

  • Lee, Jin Kyoung
    • 한국포장학회지
    • /
    • 제22권1호
    • /
    • pp.15-23
    • /
    • 2016
  • Gelatin soft capsules, manufactured by the press through package(PTP) process, are widely used in the production of multivitamin dietary supplements and other health functional foods. Gelatin capsules can prevent light and air from having a direct contact with the contents in the capsule, and the nutrients inside the capsules are preserved without any loss. In the present study, on the basis of the results on the safety of gelatin capsules. The parameters investigated included degradation of the capsules before their shelf life, capsule deformation, and changes in specific nutrients. Moisture and heat in the production and storage environments of the capsules caused the gelatin to swell and attach some of the inorganic salts in the vitamin contents. Nutritional component analysis showed that B1, B5, B9, and B12 contents were decreased, while mineral elemental analysis shown calcium, chloride, and zinc compound were found to be infused into the gelatin of the capsule shell.

Spectrofluorometric Study of the Interaction of Coumarin Derivatives with Bovine Serum Albumin

  • Kamat, B.P.;Seetharamappa, J.;Kovala-Demertzi, D.
    • Journal of Photoscience
    • /
    • 제11권2호
    • /
    • pp.65-69
    • /
    • 2004
  • The mechanism of interaction of four coumarin derivatives (CDS) with bovine serum albumin (BSA) was studied using spectrofluorometric technique. It was found that the coumarin ring common to all CDS makes major contribution to interaction. Binding affinities could be related to parachor values of CDS. Stem-Volmer plots indicated the presence of static component in the quenching mechanism. Results also showed that both tryptophan residues of protein are accessible to CDS. The high magnitude of rate constant of quenching indicated that the process of energy transfer occurs by intermolecular interaction forces and thus CDS binding site is in close proximity to tryptophan residues of BSA. Binding studies in the presence of the hydrophobic probe, 8-anilino-l-naphthalein-sulfonic acid showed that there is hydrophobic interaction between CDS and the probe and they do not share common sites in BSA. Thermodynamic parameters obtained from data at different temperatures showed that the binding of CDS to BSA involve hydrophobic bonds predominantly. The effects of various metal ions on the binding of CDS with BSA were also investigated.

  • PDF

Adsorption Kinetic Studies of 5-fluorouracil Molecules on Hydroxyapatite Surface

  • Yoon, Jiseol;Kwon, Ki-Young;Woo, Dong Kyun
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
    • /
    • pp.432.1-432.1
    • /
    • 2014
  • Hydroxyapatite (Ca10(PO4)6(OH)2) is known as the main inorganic component of mature mammalian bones and teeth. Because of its biocompatibility, hydroxyapatite has attracted much attention due to its potential applications in many biomedical researches. Here, we tested a therapeutic potential for the use of hydroxyapatite as an anticancer drug delivery vector. We prepared various types of hydroxyapatite having different chemical contents and morphologies using hydrothermal synthesis. The capability of hydroxyapatite as drug delivery materials was examined by adsorption kinetics of 5-fluorouracil molecules, a common anticancer drug, in phosphate buffered saline. We find that hydroxyapatite with smaller crystal size and higher phosphate contents shows improved adsorption property. Given that hydroxyapatite provides a scaffold for bone regeneration, these results highlight a potential use of hydroxyapatite in therapies aimed at osteosarcoma.

  • PDF

Methacryloxypropyltrimethoxysilane(MAPTMS)의 광그라프트에 의한 PET직물의 열적 안정성 향상 (Improved Thermal Stability of PET Fabrics by Photografting of Methacryloxypropyltrimethoxysilane(MAPTMS))

  • 장진호;손정아
    • 한국염색가공학회지
    • /
    • 제20권4호
    • /
    • pp.1-7
    • /
    • 2008
  • Methacryloxypropyl trimethoxysilane (MAPTMS), a hybrid organic-inorganic monomer, was photografted onto PET fabric using benzophenone (BP) as a photoinitiator. It was found that a UV energy of 43.2J/$cm^2$ was required to optimally photograft the MAPTMS onto PET fabrics which was applied with an aqueous formulation of 10% MAPTMS, 20% BP and 0.5% N-Methyldiethanol amine (MDEA). The MDEA additive was efficient in reducing atmospheric oxygen inhibition of polymer radicals which eliminated compulsory nitrogen inerting. The surface grafting of PET fabrics was verified by fourier transform infrared spectroscopy (FT-IR) and scanning electron spectroscopy (SEM). The grafted PET fabrics with the hybrid monomer showed higher thermal stability due to the introduced silane component in the monomer as ascertained by higher char content at 800$^{\circ}C$, which increased to 14.5% for the 15.8% grafting compared to 8.2% for the untreated.

산화마그네슘을 활용한 경화체의 지연제 첨가율에 따른 접착강도 특성 (Adhesion Strength Properties of Matrix Using Magnesia Accroding to Potassium Phosphate Addition Ratio)

  • 김태현;신진현;이상수
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2016년도 춘계 학술논문 발표대회
    • /
    • pp.34-35
    • /
    • 2016
  • Most of the construction adhesive may contain harmful component to the human body with an organic adhesive. In addition, when the adhesive caused hydroquinone, alkyl benzophenone, etc, also it raises the skin diseases to workers. Therefore, the inorganic adhesive development is necessary. This study was a study to know adhesive strength properties that adhesive using a magnesium oxide according to the addition ratio of the retarder. It has experiments to two types of magnesium oxide and type and ratio of retarder differently.

  • PDF

Recent Progress in the Development of Small Organic Molecules for White Organic Light Emitting Devices

  • Raja, Inam ul Haq;Jung, Se-Jin;Lee, So-Ha
    • 한국응용과학기술학회지
    • /
    • 제25권1호
    • /
    • pp.91-106
    • /
    • 2008
  • Development of white light emitting materials has been an interesting area for scientists and scientists have developed many organic, polymer and inorganic materials for white electroluminescent devices. Among them, single component small molecules gave best results in terms of efficiency, simplicity of device fabrication, and CIE values. Therefore, this review covers detailed discussion about syntheses of small compounds used in white organic light emitting devices until 2007.

$CaCO_3$/Poly ethyl methacrylate를 이용한 무독성 혼합라텍스의 개발 (A Development of Nontoxic Composite Latex Using $CaCO_3$/PEMA)

  • 설수덕;이선룡;이내우
    • 한국안전학회지
    • /
    • 제17권4호
    • /
    • pp.133-139
    • /
    • 2002
  • Core-shell polymers of inorganic/organic pair, which are consisted of both core and shell component, were synthesized by sequential emulsion polymerization using ethyl methacrylate (EMA) as a shell monomer and ammonium persulfate as initiator. We found that $CaCO_3$ core should be prepared by adding 2.0wt% SDBS(sodium dodecyl benzene sulfonate), $CaCO_3$ core/PEMA shell polymerization was carried out on the surface of $CaCO_3$ particle during EMA shell polymerization in the core-shell polymer preparation. The structure of core-shell polymer were investigated by measuring the degree on decomposition of $CaCO_3$ by HCI solution, thermal decomposition of polymer composite on thermogravimetric analyzer, glass transition temperature on differential scanning calorimeter, and morphology using scanning electron microscope.

PRODUCTION OF GINSENOSIDES THROUGH IN VITRO CULTURE OF GINSENG(Panax ginseng C.A. MEYER)

  • Choi K.T.;Ahn I.O.;Park J.C.
    • 고려인삼학회:학술대회논문집
    • /
    • 고려인삼학회 1993년도 학술대회지
    • /
    • pp.143-149
    • /
    • 1993
  • Ginseng root explants and calli induced from selected cell lines were cultured on modified Murashige and Skoog's media supplemented with different concentrations of organic or inorganic compounds and plant growth requlators to clarify the effects of chemical composition and plant growth regulators in the medium on the growth of ginseng calli and the production of ginseng saponin. For optimum growth of calli, the concentrations of 2, 4-D and sucrose were the range of 1 to 3 mg/${\ell}$l and 1 to $3\%,$ respectively. And it was clarified that sucrose, nitrogen, phosphate, calcium, magmesian plant growth regulators and their concentrations influcenced the relative biosynthesis of saponin in tissue cultures of Panax ginseng. The patterns of ginsenosides, pharmacologically useful component, were different among the cell lines and contents of ginsenosides were much higher in selected cell lines than in original cell line.

  • PDF