• 제목/요약/키워드: water soluble

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수용성 포토레지스트와 이를 이용한 유기 박막의 photolithography 공정 연구 (Photolithography process investment of water soluble photoresist and Organic thin film by using it.)

  • 김광현;김건주;류기성;김태호;송정근
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2004년도 하계종합학술대회 논문집(2)
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    • pp.497-500
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    • 2004
  • In this paper, we developed a new photolithography process which used a water-soluble photoresist instead of organic solvent soluble photoresist, defined pentacene thin film. And pentacene OTFTs were fabricated with the water- soluble photolithography process.

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수용성 식이섬유소의 점도가 혈당강하에 미치는 영향 (The Relationship between Viscosity of Soluble Dietary Fiber and their Hypoglycemic Effects)

  • 김은희
    • Journal of Nutrition and Health
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    • 제29권6호
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    • pp.615-621
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    • 1996
  • Experiments were carried out in humans to assess the relationship between viscosity and post-prandial glucose response of soluble fibers. Eight(3 male and 5 female) healthy individuals were tested for their glucose response after taking control meals or 3 test fiber meals of different viscosities. Meal viscosity of the test food was adjusted to be between 200 and 70, 000 cps. There was a significant increase in post-prandial glucose response(p=0.01) in control meals by solely increasing the volume of water. Fiber with the highest viscosity konjac mannan demonstrated the lowest relative glucose response(70.1$\pm$6.6), followed by medium viscosity xanthan (79.3$\pm$8.7)and low viscosity psyllium (86.3$\pm$10.5). The difference is significant at the level of p<0.05. However, no significant difference in relative glucose response of the same fiber was found when the 4 levels of water were added to make different meal viscosity of each fiber (p=0.476). This result suggested that hypoglycemic action of soluble dietary fibers is related to fiber viscosity rather than meal viscosity.

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아크릴 수지 수용액에서의 Carbon black의 분산에 관한 연구 (Dispersion of Carbon Black in Acrylic Resin Aqueous Solution)

  • 오지만;김성빈;권대환
    • 한국인쇄학회지
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    • 제20권1호
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    • pp.16-27
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    • 2002
  • Recently, the attraction for water-based ink is increasing, Because Solvent ink, based on organic solvent, cause bad effect on environment and rise the cost. Instead of organic solvent that cause environment pollution as well as cost-rise by rise of petroleum price, Binder based on alkali-soluble resin is popular and studied by many other country. However, in domestic, research and development for alkali-soluble resin is not like, because of lack of understanding environmental pollution and safety, therefor alkali-soluble resin development and research for the properties of the water-based ink used by alkali-soluble resin is not study very well. In this paper, we studied dispersion of carbon black in acrylic resin solution and the properties of water-based ink used by carbon black and acrylic binder.

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Immobilization Imparts Stability to Watermelon Urease to Work in Water Miscible Organic Media

  • Prakash, Om;Upadhyay, Lata Sheo Bachan
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제11권2호
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    • pp.140-145
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    • 2006
  • The behaviour of alginate immobilized and soluble watermelon (Citrullus vulgaris) urease in water miscible organic solvents like, acetonitrile, dimethylformamide (DMF), ethanol, methanol, and propanol is described. The organic solvents exhibited a concentration dependent inhibitory effect on both the immobilized and the soluble urease in the presence of urea. Pretreatment of soluble enzyme preparations with organic solvents in the absence of substrate for 10 min at $30^{\circ}C$ led to rapid loss in the activity, while similar pretreatment of immobilized urease with 50% (v/v) of ethanol, propanol, and acetonitrile was ineffective. Time-dependent inactivation of immobilized urease, both in the presence and in the absence of urea, revealed stability for longer duration of time even at very high concentration of organic solvents. The soluble enzyme, on the other hand, was rapidly inactivated even at fairly lower concentrations. The results suggest that the immobilization of watermelon urease in calcium alginate make it suitable for its application in organic media. The observations are discussed.

Synthesis of $Ba_2SiS_4:Eu^{2+}$ Blue-Green Phosphor Prepared by Spray Drying Method Using Water Soluble Silicon Compound

  • Tezuka, Satoko;Suzuki, Yoshihito;Petrykin, Valery;Kakihana, Masato
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.243-245
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    • 2009
  • The single phase $Ba_2SiS_4$ doped with $Eu^{2+}$ was successfully synthesized by direct sulfurization of an oxide precursor prepared by a spray drying method using a novel water soluble silicon compound, which remains soluble in a given aqueous solution. The intensity of the emission peak of thus obtained $Ba_2SiS_4:Eu^{2+}$ was 1.75 times larger than that of a sample prepared by a solid state reaction method, and it approached 106% compared to one of the best commercially available YAG:$Ce^{3+}$ phosphor.

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수용성 금속가공유에서 살균제 사용으로 발생된 유해인자 및 호흡기 질환 위험 고찰 (Review of Respiratory Disease and Hazardous Agents Caused by the Use of Biocide in Metalworking Operations)

  • 박동욱;고예지;윤충식
    • 한국산업보건학회지
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    • 제23권3호
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    • pp.169-176
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    • 2013
  • Objectives: The aim of this study is to critically review the health effects of not only direct exposure to biocide, but also indirect exposure to by-product hazardous agents generated through the use of biocide in metalworking operations. Methods: An extensive literature review was conducted of studies reporting on respiratory disease cases, particularly hypersensitivity pneumonitis (HP), in environments using water-soluble metalworking fluids (MWFs). Keyword search terms included 'metalworking fluids', 'machining fluids', 'metalworking operation' 'machining operation' and 'biocide', which were also used in combination. Additional articles were identified in references cited in the articles reviewed. Results: Several of the field, epidemiological and experimental studies reviewed assumed that the symptoms and signs typical of HP developed in machinists who handled water-soluble MWF could be caused by inhalation exposure to nontuberculous mycobacteria (NTM). Most NTM are known to be not only resistant to both biocide and disinfectant, but also to have acid-fast cell walls that are highly antigenic. The presence or persistence of the Mycobacterium species, referred to as NTM, in metalworking fluid-using operations may be caused by NTM contamination in either the natural water or tap water that is used to dilute the base oil and additives for water-soluble MWFs. This hypothesis that NTM contamination in water-soluble MWFs is a causative agent of HP has high biologic plausibility, such as antigenic property, hydrophobicity and small diameter (< 5 um). Conclusions: Aerosolized mycobacteria colonized from MWF are likely to be causing the HP. Inhalation exposure to mycobacteria should be considered as a possible cause for the development of HP.

Preparation and Characterization of Cisplatin-Incorporated Chitosan Hydrogels, Microparticles, and Nanoparticles

  • Cha, Ju-Eun;Lee, Won-Bum;Park, Chong-Rae;Cho, Yong-Woo;Ahn, Cheol-Hee;Kwon, Ick-Chan
    • Macromolecular Research
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    • 제14권5호
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    • pp.573-578
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    • 2006
  • Three different, polymer-platinum conjugates (hydrogels, microparticles, and nanoparticles) were synthesized by complexation of cis-dichlorodiammineplatinum(II) (cisplatin) with partially succinylated glycol chitbsan (PSGC). Succinic anhydride was used as a linker to introduce cisplatin to glycol chitosan (GC). Succinylation of GC was investigated systematically as a function of the molar ratio of succinic anhydride to glucosamine, the methanol content in the reaction media, and the reaction temperature. By controlling the reaction conditions, water-soluble, partially water-soluble, and hydrogel-forming PSGCs were synthesized, and then conjugated with cisplatin. The complexation of cisplatin with water-soluble PSGC via a ligand exchange reaction of platinum from chloride to the carboxylates induced the formation of nano-sized aggregates in aqueous media. The hydrodynamic diameters of PSGC/cisplatin complex nano-aggregates, as determined by light scattering, were 180-300 nm and the critical aggregation concentrations (CACs), as determined by a fluorescence technique using pyrene as a probe, were $20-30{\mu}g/mL$. The conjugation of cisplatin with partially water-soluble PSGC, i.e., borderline between water-soluble and water-insoluble PSGC, produced micro-sized particles $<500{\mu}m$. Cisplatin-complexed PSGC hydrogels were prepared from water-insoluble PSGCs. All of the cisplatin-incorporated, polymer matrices released platinum in a sustained manner without any significant initial burst, suggesting that they may all be useful as slow release systems for cisplatin. The release rate of platinum increased with the morphology changes from hydrogel through microparticle to nanoparticle systems.

방화피복재 개발을 위한 용해성 규산염의 수화특성에 관한 연구 (A Study of Hydration Characteristics on Soluble Silicate to Develop Fire Protective Coating)

  • 김정훈;이내우
    • 한국안전학회지
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    • 제11권1호
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    • pp.90-98
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    • 1996
  • In order to investigate the effects on intumescence to fire protective coatings, the characteristics of solubility, hygroscopic nature and X-ray diffration results on soluble silicate were determined. Solubility is depended on the mutual action of each silicate. In the result of hygroscopic characteristics by water absorption under several kinds of relative humidity, lithium silicate is more stable than sodium and potassium silicate over moistures. Eventhough free water is evaporated over $100^{\circ}C$ , physically adsorption water and ionic water are eliminated about $200^{\circ}C$, but evolution of structural water is expected to be emitted between 400~$600^{\circ}C$ range. Those are considered to be contributed intumescence on soluble silicate.

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Preparation of Highly Water Soluble Tacrolimus Derivatives: Poly(Ethylene Glycol) Esters as Potential Prod rugs

  • Chung, Yong-Seog;Cho, Hoon
    • Archives of Pharmacal Research
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    • 제27권8호
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    • pp.878-883
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    • 2004
  • Tacrolimus (FK506), which is isolated from Streptomyces tsukubaensis, is a new potent immu-nosuppressant. Because of poor solubility in water, the conventional intravenous dosage forms of tacrolimus contain surfactants such as cremophor EL (BASF Wyandotte Co.) or hydroge-nated polyoxy 60 castor oil (HCO-60) which may cause adverse effects. This study relates to a polymer-tacrolimus conjugate, which can be dissolved in water, formed by chemically binding the sparingly soluble drug, tacrolimus, with the water soluble polymer, methoxypoly(ethylene glycol) (mPEG). Water soluble tacrolimus-mPEG conjugates have been synthesized and shown to be function in vitro as prodrugs. These conjugates are in the form of an ester wherein the 24-, 32- or 24,32-positions are esterified. The desired 24-, 32- or 24,32-esterified com-pounds were obtained by initially acylating of tacrolimus with iodoacetic acid at the 24-,32-, or 24,32-positions and then reacting the resulting acylated tacrolimus with a mPEG in the pres-ence of a base such as sodium bicarbonate. These conjugates were converted again into tac-rolimus by the action of enzymes in human liver homogenate, and the half-lives of the conjugates are approximately 10 min in the homogenate, indicating that the esterified tacroli-mus derivatives may be practically applicable as a prod rug for the immunosuppressant.

Immune-Enhancing Alkali-Soluble Glucans Produced by Wild-Type and Mutant Saccharomyces cerevisiae

  • Ha Chang-Hoon;Lim Ki-Hong;Jang Se-Hwan;Yun Cheol-Won;Paik Hyun-Dong;Kim Seung-Wook;Kang Chang-Won;Chang Hyo-Ihl
    • Journal of Microbiology and Biotechnology
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    • 제16권4호
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    • pp.576-583
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    • 2006
  • The alkali-soluble glucan of the yeast cell wall contains $\beta-(1,3)-$ and (1,6)-D-linkages and is known to systemically enhance the immune system. In the previous study [6], in order to isolate cell wall mutants, a wild-type strain was mutagenized by exposure to ultraviolet light, and the mutants were then selected via treatment with laminarinase $(endo-\beta-(1,3)-D-glucanase)$. The mass of alkali- and water-soluble glucans produced by the mutant was measured to be 33.8 mg/g of the dry mass of the yeast cell. Our results showed that the mutants generated the amount of alkali-soluble glucan 10-fold higher than that generated by the wild-type. Structural analysis showed that the alkali-soluble glucan from the mutants was associated with a higher degree of $\beta-(1,6)-D-linkage$ than was observed in conjunction with the wild-type. Yeast cell wall $\beta-glucan$ was shown to interact with macrophages via receptors, thereby inducing the release of tumor necrosis factor alpha $(TNF-\alpha)$ and nitric oxide. Alkali-soluble $\beta-glucans$, both from water-soluble and water-insoluble glucan, exhibited a higher degree of macrophage activity with regard to both the secretion of tumor necrosis factor alpha $(TNF-\alpha)$ and nitric oxide and direct phagocytosis, than did the positive control ($1{\mu}g$ of lipopolysaccharide).