• Title/Summary/Keyword: Solvent treatment

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Solvent Effects on the Solvolysis of 1-(4-Methoxyphenyl)-1-phenyl-2,2,2-trifluoroethyl Choloride. Influence of an Electron-Withdrawing α-Substituent on Carbonium Ion Center

  • 권정민;김성홍;여수동
    • Bulletin of the Korean Chemical Society
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    • v.17 no.11
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    • pp.1056-1061
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    • 1996
  • Solvolysis rates of 1-(4-methoxyphenyl)-l-phenyl-2,2,2-trifiuoroethyl chloride (1) and 1-(4-methoxyphenyl)-1-phenylethyl chloride (2) were measured in a variety of aqueous binary solvents, and the solvent effect was treated with the Grunwald-Winstein equation. The solvent effect on the solvolysis of 1 failed to give a single linear correlations using the ordinary Y or YCl, but exhibited the wide split pattern which could not be related to the solvent nucleophilicity. The improved correlations with YBnCl and extended dual-parameter treatment, log (k/k0)=mYCl+hI (mΔYΔ), were observed for the solvolysis of 1. These results suggest that the incipient cationic charge in the solvolysis of 1 is delocalized strongly into the aryl-rings in the transition state. While the solvent effect on the solvolysis of 2 is better correlated with Y or YCl than YBnCl but the linearity is not satisfactory. The correlation is comparably improved by the use of the extended Grunwald-Winstein equation, log (k/k0)=0.81YCl+0.26NOTs (R=0.994, SD=±0.12), indicating the cationic charge of reaction center of 2 was localized mostly in the transition state.

Cleaning with Organic Solvent (유기용제에 의한 탈지세정 (도장전처리로써의))

  • 죽내절삼
    • Proceedings of the Korean Professional Engineer Association Conference
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    • 1984.03a
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    • pp.52-60
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    • 1984
  • As far as we handle industrial products, the painting process is prerequisite; and the preparatory treatment of materials is, therefore, indispensable to the above process. However, it is a matter for regret that people are liable to overlook the importance the treatment of materials at the preparatory stage, giving themselves up to the surface of finished goods. The preparatory treatment of materials is like backstage personnel (operations) in dramatic performance; the performance cannot be successful without the support of backstage operations in surface treatment. The various methods which are being applied widely as preparatory treatment are as follow: (1) the method by using hand tools such as grinders, etc. (2) the method with blasting (3) the method with chemical coating (4) the method by getting rid of fatty substance with organic solvent The methods No. 1 and No. 2 are in use mainly for larger structures, and those No. 3 and No. 4, either singly or combined, are applied for mass-produced, smaller items (acid cleaning is applied for getting rid of rust, as the case may be). The method No. 3 is used mainly as anti-rust by forming zinc phosphate film on the surface of steel plate or enhancing the bonding power of paints by taking advantage of irregular surfaces of films. Recently are no the market steel plates treated directly with film-coating by omitting the process No. 3. Furthermore, those goods painted include not only nonferrous goods but plastics and elastomer. The present discourse describes the cleaning process by using the steam of organic acid, picked up from among No. 4, and its equipment applied.

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Effects of Various Mechanical and Chemical Treatments of Rapeseed Meal on the Performance of Broilers

  • Khan, M.Z.;Mahmood, S.;Sarwar, M.;Nisa, M.;Gulzar, F.
    • Asian-Australasian Journal of Animal Sciences
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    • v.11 no.6
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    • pp.708-712
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    • 1998
  • One hundred and eighty, 1-day old broiler chicks, randomly divided into 15 replicates of 10 brids each were employed to six treatment rations (A, B, C, D, E and F). Rapeseed meal (RSM) with or without treatment was incorporated in the rations at 20 percent level in lieu of soybean meal. The birds in group A were fed soybean based ration and those in group B, C, D, E and F were given ration containing untreated, solvent extracted, water treated, autoclaved and ferrous sulphate treated RSM, respectively. Presence of RSM in the rations whether untreated or treated, significantly reduced weight gain and feed consumption of the birds compared with those of control group but efficiency of feed utilization, dressed weight, dressing percentage and weights of internal organs amongst the groups remained unaffected. The size of thyroid galnds of the broilers using the meal was significantly larger than those having ration without RSM. The only exception was that the birds having solvent extracted meal had similar thyroid gland relative weight as those of control group indicating reduced antinutritional effect of isothiocyanates content due to solvent extraction of the meal.

Strengthening Treatment of Aged Hanji with Solvent Soluble Polymers (용제 용해형 고분자를 이용한 열화한지의 보강처리)

  • Kim, Kang-Jae;Lee, Min-Hyung;Eom, Tae-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.44 no.1
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    • pp.1-9
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    • 2012
  • In this study, 5 solvent soluble polymers were treated on Hanji. Mechanical properties, morphology and oxidation index with thermal aging were measured on the aged Hanji, dewaxed Hanji and polymer treated Hanji. Synthetic polymers(such as polylactic acid, polybutylene succinate, polystyrene) treated Hanji had higher strength and thermal stability than cellulose derivatives(such as cellulose nitrate and cellulose acetate) treated Hanji. Polymer treated Hanji showed a little bit of color change. The oxidation index of PS treated Hanji did not increase with thermal aging because it did not have a carboxyl group in chemical structure. Finally, polystyrene was found to be the most efficient method for strengthening the dewaxed Hanji. The best aging safety and thermal stability were obtained at the polystyrene 3% solution.

Cleaning Fabricated Metal Thread: A Post-treatment Stability Assessment after Artificial Deterioration and the Application of Synthetic Soil

  • Park, Hae Jin;Hwang, Minsun;Chung, Yong Jae
    • Journal of Conservation Science
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    • v.35 no.1
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    • pp.19-31
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    • 2019
  • To study the cleaning effects and post-treatment stability assessment of various methods of cleaning textiles with metal thread, six naturally-soiled historical textiles with metal thread were investigated at the Metropolitan Museum of Art, New York. Prior to the cleaning of fabricated gold, silver, and copper thread that had been glued onto a paper substrate, the artificial deterioration was carried out in a controlled environment with light(UV and daylight), and temperature and humidity factors which would weaken and damage the samples. A synthetic soil mixture was applied to the samples to imitate soil found on the historic and archaeological textiles with metal thread; the cleaning effect and post-treatment assessment were investigated by use of three textile cleaning methods: mechanical cleaning, wet cleaning, and solvent cleaning. While investigating the naturally-soiled textiles with metal thread, it was determined that the soil colors and sizes of contaminating particles of each textile were different due to the diversity of original environmental factors and conditions. After cleaning with kneaded rubber, Stoddard solvent, n-decane or n-hexane, a bright, clean effect was apparent. Kneaded rubber was successful in picking up both large and small particles, but its stickiness caused some of the metal leaf to peel off. Stoddard solvent produced a good cleaning effect, but after use of n-hexane and n-decane in the cleaning process, a white layer of residue remained on the textile's surface. Wet cleaning was not effective and the rapid humidity changes between wet and dry conditions caused the edges of the paper substrate to lose their original shape.

The Effect of Solvent Treatment on the Microstructure and Surface Morphology of PET POY (폴리에스테르 부분배향사의 용매처리에 따른 내부구조 및 표면형태의 변화)

  • 신혜원;유효선
    • Journal of the Korean Society of Clothing and Textiles
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    • v.20 no.3
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    • pp.467-480
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    • 1996
  • Interactions between PET POY and solvents were estimated by the changes in microstructure and surface morphology. Changes in microstructure and surface morphology by the solvent treatments were: an increase in crystallite size, a decrease in interplanar spacing, a change in degree of orientation of crystalline region, a change in surface characteristics.

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Dry-Heat Treatment Process for Enhancing Viral Safety of an Antihemophilic Factor VIII Concentrate Prepared from Human Plasma

  • Kim, In-Seop;Choi, Yong-Woon;Kang, Yong;Sung, Hark-Mo;Shin, Jeong-Sup
    • Journal of Microbiology and Biotechnology
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    • v.18 no.5
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    • pp.997-1003
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    • 2008
  • Viral safety is a prerequisite for manufacturing clinical antihemophilic factor VIII concentrates from human plasma. With particular regard to the hepatitis A virus (HAV), a terminal dry-heat treatment ($100^{\circ}C$ for 30 min) process, following lyophilization, was developed to improve the virus safety of a solvent/detergent-treated antihemophilic factor VIII concentrate. The loss of factor VIII activity during dry-heat treatment was of about 5%. No substantial changes were observed in the physical and biochemical characteristics of the dry-heat-treated factor VIII compared with those of the factor VIII before dry-heat treatment. The dry-heat-treated factor VIII was stable for up to 24 months at $4^{\circ}C$. The dry-heat treatment after lyophilization was an effective process for inactivating viruses. The HAV, murine encephalomyocarditis virus (EMCV), and human immunodeficiency virus (HIV) were completely inactivated to below detectable levels within 10 min of the dry-heat treatment. Bovine herpes virus (BHV) and bovine viral diarrhea virus (BVDV) were potentially sensitive to the treatment. However porcine parvovirus (PPV) was slightly resistant to the treatment. The log reduction factors achieved during lyophilization and dry-heat treatment were ${\geq}5.55$ for HAV, ${\geq}5.87$ for EMCV, ${\geq}5.15$ for HIV, 6.13 for BHV, 4.46 for BVDV, and 1.90 for PPV. These results indicate that dry-heat treatment improves the virus safety of factor VIII concentrates, without destroying the activity. Moreover, the treatment represents an effective measure for the inactivation of non-lipid-enveloped viruses, in particular HAV, which is resistant to solvent/detergent treatment.

Control of Nano-Structure of Ceramic Membrane and Its Application (세라믹 멤브레인의 나노구조 제어 및 응용)

  • Lee, Hye-Ryeon;Seo, Bong-Kuk;Choi, Yong-Jin
    • Membrane Journal
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    • v.22 no.2
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    • pp.77-94
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    • 2012
  • Amorphous ceramic membranes have been developed for gas phase separation and liquid phase separation (water treatment, wastewater treatment and separation of organic solvent or compounds) because of their thermal stability and solvent resistance. In this paper, ceramic membranes were categorized by membrane pore size and materials, and summarized for hydrogen separation, carbon dioxide separation, membrane reactor, pervaporation and water treatment with membrane structure and properties.

A study for cyclic Process technique of mineral base engine used oil resource (Engine 폐유 자원순환 기술에 관한 연구)

  • 김주항
    • Journal of the Korean Professional Engineers Association
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    • v.18 no.2
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    • pp.6-15
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    • 1985
  • A new process disregraded the H$_2$SO$_4$ treatment process heretofore in use, was developed and substituted for mineral base engine used oil of homemade SAE-30 grade H.V.I., which was used covering 4,500km, as samples, and the following results in research, was obtained. (1) A good quality of rerefinded base oil was obtained through roughly a course of developed processes of vacuum distillation process, solvent extraction process, neutralization treatment process and clay treatment process. (2) Through vacuum distillation process, the size of fine grains of insoluble colloid carbon that is, colloid carbon which was produced by burning of internal combustion engine oil and fuel, could be brought up and precipitated (3) The insoluble matters and admixtures could be easily dispersed and dissolved by mixing and extracting solvent disregarded the H$_2$SO$_4$ treatment process heretofore in use (4) waste matter heretofore called acid sludge in consequence of the process, did not appear at all. accordingly, the environmental pollution could be removed. (5) The troubles of corrosion to copper strip which was faults of the usual used oil refined products and peculiar offensive odor of the rerefined oil, could be solved through the neutralization process. (6) The yield of rerefined oil obtained through a course of processes was over 86 percent, and it is of practical use, not to speak of commercial value.

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Studies on the Characteristics of EVA Foam by Solvent Treatment (용매 처리에 의한 EVA foam 표면 특성에 관한 연구)

  • Chun, Jae Hwan;Kim, Gu Ni;Hong, Soon Yeong;Yoo, Chong Sun;Oh, Sang Taek
    • Journal of Adhesion and Interface
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    • v.2 no.3
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    • pp.9-15
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    • 2001
  • To estimate the effect of the surface state of the EVA foam on an adhesion, the surface was treated with solvents having different values of a solubility parameter and a surface tension. The morphology and the contact angle were measured by SEM and contact angle tester, respectively. The value of the critical surface tension(${\gamma}_{c,0}$) of the EVA foam calculated by Zismann plot was 27.08 dyne/cm. The surface state and the ${\gamma}_c$ of the EVA foam were changed by solvent treatment. The swelling ratio of EVA foam was influenced by solubility parameter of a solvent, on the other hand the degree of change in the surface state was dependent on a surface tension of a solvent. When a surface tension of solvent. When a surface tension of solvent is lower than ${\gamma}_{c,0}$ of the EVA foam, the wettability of a solvent was good and the surface state was greatly changed. The adhesion strength of EVA foam was greatly improved to above 600% as compared to that of the untreated one. As the ${\gamma}_c$ of EVA was closed to the surface tension of the primer, the good adhesion strength was obtained.

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