• Title/Summary/Keyword: Perm

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A Study of Hair Damage depending on Hair Treatment Conditions and Morphological Change in Hair (트리트먼트 처리조건에 따른 모발 손상 및 형태학적 변화에 관한 연구)

  • Joo, Yeon Bin;Lim, Sun Nye
    • Textile Coloration and Finishing
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    • v.27 no.3
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    • pp.219-227
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    • 2015
  • This study aims to propose a method to reduce hair damage after investigating the following: the factors which vary depending on hair treatment conditions; the degree of hair damage in the bleached sample; and an analysis of the effects of a perm on wave formation. To determine the effects of these treatment types, hair bleach was mixed with the hair treatment, and hair damage and formation of permanent waves were examined. Using a scanning electron microscope, in addition, morphological changes were analyzed and the following results were obtained: After mixing natural powder(2.5g) and hair cream(2.5g) and bleaching the mixture, it was compared to the scale structure of untreated hair. When 5g of natural powder was mixed and bleached, a clear layer was observed among cuticle scales, showing the effects of hair treatment. Therefore, this confirms that the effects of hair treatment were most notable when grain powder was mixed with hair cream. Once hair is damaged, it is almost impossible to regain its original state. When chemical agents are used, therefore, it is important to consider the possible hair damage they cause.

Research Trends and Prospects of Reverse Electrodialysis Membranes (역전기투석용 이온교환막의 연구동향 및 전망)

  • Hwang, Jin Pyo;Lee, Chang Hyun;Jeong, Yeon Tae
    • Membrane Journal
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    • v.27 no.2
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    • pp.109-120
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    • 2017
  • The reverse electrodialysis (RED) is an energy generation system to convert chemical potential of saline water directly into electric energy via the combination of current derived from a redox couple electrolyte and ionic potential obtained when cation ($Na^+$) and anion ($Cl^-$) pass through cation exchange membrane (CEM) and anion exchange membrane (AEM) into fresh water, respectively. Ion exchange membrane, a key element of RED system, should satisfy requirements such as 1) low swelling behavior, 2) a certain level of ion exchange capacity, 3) high ion conductivity, and 4) high perm-selectivity to achieve high power density. In this paper, research trends and prospects of ionomer materials and ion exchange membranes are dealt with.

Research Trend of Membrane Technology for Separation of Carbon Dioxide from Flue Gas (온실기체 분리회수를 위한 막분리기술 연구 동향)

  • 김정훈;임지원;이수복
    • Membrane Journal
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    • v.12 no.3
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    • pp.121-142
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    • 2002
  • The $CO_2$ emission is the largest contribute for the green house effect. Among the existing chemical separation processes, the membrane separation technology is(/will be) the most potential process for $CO_2$, separation from flue gas. Based on the solution-diffusion theory and physical properties of carbon dioxide/nitrogen and the permeation data in the literature, the relationships between physico-chemical structures of polymeric membrane materials and the perm-selectivities for $CO_2$/$N_2$ gases were described in detail. The progress of membrane module and process development was introduced briefly. Finally, the worldwide research activity including South Korea's for carbon dioxide separation by membrane technology were introduced through the survey of papers and technical reports published.

A Study of the Sex-role Perceptions Reflected upon the Term “Be Like ∼” (남 .여 대학생의 "~답다"에 대한 성 역할 지각에 관한 연구 -두발, 신발, 장신구를 중심으로-)

  • 한명숙;하희정
    • The Research Journal of the Costume Culture
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    • v.11 no.5
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    • pp.767-777
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    • 2003
  • This study defines attributes of the Korean costume culture, focussed on hair, shoes and accessories which express sex-roles, encapsulated in the term, “be like...”. A group of 362 male and female university students from Seoul and Gyeonggi area was surveyed for the study. The statistical analysis of SPSS 10.0 was applied for analyzing the data, and the significant variances were reviewed by the basic statistics and t-test. The results are as follows; First, short hair is perceived as the typical hair style that symbolizes male, both from male and female university students. Hair colors in warm color such as brown, wine, purple, lemon and orange, and the style of hair such as bobbed, long, and perm are perceived as definite clues that symbolized female. Second, when it concerns the types of shoes, both male and female university students cited oxford as the typical clue that symbolizes male, whereas pumps and sandal were cited for female. Third, in terms of types of accessories, both male and female university students perceived necklace, earring, bracelet, hair pin and band, scarf, and muffler as very feminine. Among these, hair pin and band, and scarf are evaluated as the typical clues that signify the role of females. Necktie is perceived as the typical clue that signify male role.

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Hydrogen Permeance of Ce1-xYxO2-δ Membranes According to Yttrium Content

  • Song, Da-Heoi;Jung, Mie-Won
    • Journal of the Korean Ceramic Society
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    • v.50 no.6
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    • pp.451-453
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    • 2013
  • Porous ceramic membranes consisting of $Ce_{1-x}Y_xO_{2-{\delta}}$ were developed for hydrogen permeation tests. Various amounts (x = 0, 0.05, 0.1, 0.2) of yttrium were doped to ceria to study the effect of yttrium doping on ceria membranes on various properties, including hydrogen permeability. $Ce_{1-x}Y_xO_{2-{\delta}}$ powder was synthesized by the sol-gel method. These membranes were fabricated by pressing and sintering at $1300^{\circ}C$ for 6 h. As the amount of yttrium increased, the grain size of the membrane decreased. Hydrogen permeability was improved as the yttrium content increased. Selective permeability of hydrogen compared to CO is explained by electric conductivity. As the temperature rose, both the hydrogen perm-selectivity and electric conductivity on $Ce_{0.8}Y_{0.2}O_{1.9}$ improved.

Controlling the pore size of macroporous membranes by adding non-solvent

  • Shin, Se-Jong;Im, Se-Jun;Park, Seung-Ryul;Lee, Seung-Yun;Min, Byoung-Ryul
    • Proceedings of the Membrane Society of Korea Conference
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    • 2003.07a
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    • pp.107-114
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    • 2003
  • This study investigated the effect of 2-methoxy ethanol (2-Me) non-solvent as additive included in casting solution. Macroporous polymer membranes were prepared by using polyethersufone (PES)/N-methyl-2-pyrrolidone (NMP)/2-Me casting solution and water coagulant. The phase separation co-process of the vapor-induced phase separation (VIPS) and liquid-induced phase separation (LIPS) were used by means of membrane preparation method. The pore size and pore size distribution were controlled with additive (non-solvent), and measured with Automated Perm Porometer. By increasing additive (non-solvent) in the casting solution, the membranes produced changed from finger structure to sponge structure. That is due to the different diffusion rates. At slow diffusion process, sponge-like structure was formed and at fast diffusion process, finger-like structure was formed. Also relative humidity, evaporation time, temperature of casting solution and coagulation bath etc. had effects on the pore size distribution and the porosity of the membrane.

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Trends in Monoclonal Antibody Production Using Various Bioreactor Systems

  • Jyothilekshmi, I.;Jayaprakash, N.S.
    • Journal of Microbiology and Biotechnology
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    • v.31 no.3
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    • pp.349-357
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    • 2021
  • Monoclonal antibodies are widely used as diagnostic reagents and for therapeutic purposes, and their demand is increasing extensively. To produce these proteins in sufficient quantities for commercial use, it is necessary to raise the output by scaling up the production processes. This review describes recent trends in high-density cell culture systems established for monoclonal antibody production that are excellent methods to scale up from the lab-scale cell culture. Among the reactors, hollow fiber bioreactors contribute to a major part of high-density cell culture as they can provide a tremendous amount of surface area in a small volume for cell growth. As an alternative to hollow fiber reactors, a novel disposable bioreactor has been developed, which consists of a polymer-based supermacroporous material, cryogel, as a matrix for cell growth. Packed bed systems and disposable wave bioreactors have also been introduced for high cell density culture. These developments in high-density cell culture systems have led to the monoclonal antibody production in an economically favourable manner and made monoclonal antibodies one of the dominant therapeutic and diagnostic proteins in biopharmaceutical industry.

Organotemplate-free synthesis of ZSM-5 membrane for pervaporation dehydration of isopropanol

  • Li, Jiajia;Li, Liangqing;Yang, Jianhua;Lu, Jinming;Wang, Jinqu
    • Membrane and Water Treatment
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    • v.10 no.5
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    • pp.353-360
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    • 2019
  • ZSM-5 membrane was prepared on tubular macroporous ${\alpha}$-alumina support using a different synthesis route. The effects of organic template agent and Si/Al ratio of the synthesis gel on morphology, structure, and separation performance of the ZSM-5 membrane used for dehydration of isopropanol were investigated. High water perm-selectivity ZSM-5 membrane with a thickness of about $3.0{\mu}m$ and a low Si/Al ratio of 10.1 was successfully prepared from organotemplate-free synthesis gel with a molar composition of $SiO_2$ : $0.050Al_2O_3$ : $0.21Na_2O$ : NaF : $51.6H_2O$ at $175^{\circ}C$ for 24 h. The ZSM-5 membrane exhibited high pervaporation performance with a flux of $3.92kg/(m^2{\cdot}h)$ and corresponding separation factor of higher than 10,000 for dehydration of 90 wt.% isopropanol/water mixture at $75^{\circ}C$.

Exploring Student Engagement on Library Facebook Pages: A Survey of Vietnamese Academic Libraries

  • Chi, Duong Thi Phuong
    • Journal of Information Science Theory and Practice
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    • v.10 no.2
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    • pp.17-29
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    • 2022
  • Facebook is very popular among young people and especially university students. Therefore, Facebook is the most logical platform to be used by academic libraries for promotional purposes and reaching out to user communities. This study aims to measure the effectiveness of using Facebook in connecting with students in academic libraries. A questionnaire survey was conducted to collect research data from students at four Vietnamese universities. A total of 1,670 valid questionnaires were returned, and more than half of the respondents were females between the ages of 18 and 22 years. The survey results found that libraries' Facebook pages did not receive adequate attention and interaction from students. Besides that, the information needs of students and social media content in general affected student acceptance of libraries' Facebook pages. These factors are demonstrated by the great majority of students who used Facebook often for various purposes, but fewer accessed library pages and they were not actively engaged in library posts. Students were interested in the information they already tended to get from libraries and were optimistic about the quality of library posts. However, they still expected more diverse and attractive content from the libraries. The findings of this study can help libraries create a close connection with students by satisfying their needs and expectations on Facebook.

The Effect of Sputtering Process Variables on the Properties of Pd Alloy Hydrogen Separation Membranes (스퍼터 공정변수가 팔라듐 합금 수소분리막의 특성에 미치는 영향)

  • Han, Jae-Yun;Joo, Sae-Rom;Lee, Jun-Hyong;Park, Dong-Gun;Kim, Dong-Won
    • Journal of the Korean institute of surface engineering
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    • v.46 no.6
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    • pp.248-257
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    • 2013
  • It is generally recognized that thin Pd-Cu alloy films fabricated by sputtering show a wide range of microstructures and properties, both of which are highly dependent on the sputtering conditions. In view of this, the present study aims to investigate the relationship between the performance of hydrogen separation membranes and the microstructure of Pd alloy films depending on sputtering deposition conditions such as substrate temperature, working pressure, and DC power. We fabricated thin and dense Pd-Cu alloy membranes by the micro-polishing of porous Ni support, an advanced Pd-Cu sputtered multi-deposition under the conditions of high substrate temperature / low working pressure / high DC power, and a followed by Cu-reflow heat-treatment. The result of a hydrogen permeation test indicated that the selectivity for $H_2/N_2$ was infinite because of the void-free and dense surface of the Pd alloy membranes, and the hydrogen permeability was 10.5 $ml{\cdot}cm^{-2}{\cdot}min^{-1}{\cdot}atm^{-1}$ for a 6 ${\mu}m$ membrane thickness.