• 분석과학
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• 제34권2호
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• pp.46-55
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• 2021

Evaluation of drug-excipient compatibility is one of the basic steps in the preformulation of pharmaceutical dosage forms. Some reactive excipients have been known so far which may cause stability problems for drug molecules in pharmaceutical dosage forms. The aim of this study was to evaluate drugexcipient compatibility of gliclazide with some common pharmaceutical excipients, known for their ability to incorporate in drug-excipient interactions. Binary mixtures were prepared using lactose, magnesium stearate, polyvinylpyrrolidone, sodium starch glycolate, polyethylene glycol 2000 and dicalcium phosphate. Based on the results; gliclazide was incompatible with all tested excipients; but not with dicalcium phosphate. DSC (Differential Scanning Calorimetry) results were in accordance with HPLC (High Pressure liquid chromatography) data and were more predictive than FTIR (Fourier Transform Infrared Spectroscopy). Drug and reactive excipients incompatibility was fully discussed and documented. It is advisable to avoid incompatible excipients or carefully monitor the drug stability when incorporating such excipients in final formulation designs.

• Environmental Engineering Research
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• 제20권3호
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• pp.205-211
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• 2015

Reduced forms of iron, such as zero-valent ion (ZVI) and ferrous ion (Fe[II]), can activate dissolved oxygen in water into reactive oxidants capable of oxidative water treatment. The corrosion of ZVI (or the oxidation of (Fe[II]) forms a hydrogen peroxide ($H_2O_2$) intermediate and the subsequent Fenton reaction generates reactive oxidants such as hydroxyl radical ($^{\bullet}OH$) and ferryl ion (Fe[IV]). However, the production of reactive oxidants is limited by multiple factors that restrict the electron transfer from iron to oxygen or that lead the reaction of $H_2O_2$ to undesired pathways. Several efforts have been made to enhance the production of reactive oxidants by iron-induced oxygen activation, such as the use of iron-chelating agents, electron-shuttles, and surface modification on ZVI. This article reviews the chemistry of oxygen activation by ZVI and Fe(II) and its application in oxidative degradation of organic contaminants. Also discussed are the issues which require further investigation to better understand the chemistry and develop practical environmental technologies.

• Clinical and Experimental Pediatrics
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• 제54권7호
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• pp.313-315
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• 2011

Reactive arthritis comprises a subgroup within infection-associated arthritides in genetically susceptible hosts. Researchers and clinicians recognize two clinical forms of reactive arthritis which occurs after genitourinary tract infection and after gastrointestinal tract infection. Chlamydia infection has been implicated as the most common agent associated with post-venereal reactive arthritis. Studies have proposed Shigella infection, Salmonella infection, or Yersinia infection as the microorganisms responsible for the post-dysenteric form. The human leukocyte antigen (HLA)-B27 antigen is the best-known predisposing factor. We report a case of HLA-B27-associated reactive arthritis after Salmonella enteritis at Pusan National University hospital.

• 한국염색가공학회지
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• 제15권5호
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• pp.301-309
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• 2003

Of the various types of dye that can be used to apply polyamide fibers, acid dyes and pre-metallised acid dyes are great in use so far. However, since these acid dyeings suffer from dye loss during laundering, recourse to an aftertreatment is usually necessary to achieve adequate fastness to washing. In the case of reactive dyes, the characteristically high washfastness of dyeings comes with the concomitant advantages of brightness and low environmental impact. Despite the obvious advantages, the commercialization of reactive dyes for polyamide fibers has not gained widespread success. In this context, the rewards for approach are likely to be considerable. Heterobifunctional reactive dyes were applied to polyamide fibers using various conditions. Optimum conditions and fixation were determined. The forms in which the vinylsulphone and hydrolyzed moieties were examined using HPLC-Mass. In addition, it was found that the extent of the washfastness secured, in terms of both change in color and staining of adjacent multifiber was being acceptable.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2002년도 제9회 학술 발표회 프로그램과 논문초록
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• pp.30-30
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• 2002

The native forms of common globular proteins are in their most stable state but the native forms of plasma serpins (serine protease inhibitors) show high-energy state interactions. The high-energy state strain of a ${\alpha}$$_1$-antitrypsin, a prototype serpin, is distributed throughout the whole molecule, but the strain that regulates the function directly appears to be localized in the region where the reactive site loop is inserted during complex formation with a target protease.(omitted)

• 한국대기환경학회지
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• 제16권4호
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• pp.309-316
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• 2000

Chemical compositions of air pollutants with fine particles (<2.5 ${\mu}{\textrm}{m}$, PB2.5) were evaluated at background site. Kangwha. in Korea during the winter season. The data set was obtained for seventeed days with 24-hour sampling from December 11 to 16, 1996 and from January 9 to 1997. The chemical species have been measured {{{{ {SO }`_{4 } ^{2- } }}}}, {{{{ { NO}`_{3 } ^{- } }}}}, {{{{ { NH}`_{4 } ^{+ } }}}}. OC and EC in the particulate phase, NH3 HNO3, HCl and SO2 in the gas phase using the three stage filter pack method. Mean concentration ($\mu\textrm{g}$/m3) of this study were : 35.42 for PM2.5 8.78 for organic carbon (OC) 7.25 for nss {{{{ {SO }`_{4 } ^{2- } }}}}, 4.94 for {{{{ { NO}`_{3 } ^{- } }}}}, 3.58 for {{{{ { NH}`_{4 } ^{+ } }}}} and 1.48 for elemental carbon (EC) respectively. Contributive rates of major particulate components in PM2.5 were OC (25%) nss- {{{{ {SO }`_{4 } ^{2- } }}}}(20%) ,{{{{ { NO}`_{3 } ^{- } }}}}(14%) {{{{ { NH}`_{4 } ^{+ } }}}}(10%) and EC (4%) respectively and these components could be accounted for 73% of PM2.5 mass. Reactive forms of {{{{ { NH}`_{4 } ^{+ } }}}} were considered as NH4HO3 and NH4{{{{ {SO }`_{4 } ^{2- } }}}} during the sampling periods. {{{{ { NO}`_{3 } ^{- } }}}}/({{{{ { NO}`_{3 } ^{- } }}}} + HNO3) and {{{{ {SO }`_{4 } ^{2- } }}}}/({{{{ {SO }`_{4 } ^{2- } }}}} + SO2) were calculated 0.8 and 0.9 respectively. Most of these compounds might be formed in partiiculate phase in the air. Correlation coefficient between OC and EC was 0.866 which might have the same sources during the sampling periods,.

• Reproductive and Developmental Biology
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• 제38권1호
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• pp.1-8
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• 2014

Artificial insemination technique has been contributed immensely for production of livestock worldwide as a critical assisted reproductive technique to preserve and propagate excellent genes in domestic animal industry. In the past decade, methods for semen preservation have been improved mostly in liquid preservation method for boar semen and freezing method for bull semen. Among many factors affecting semen quality during preservation, reactive oxygen species, produced by aerobic respiration in sperm for survival and motility, are unfavorable to sperm physiology. In mammalian cell as well as in the sperm, antioxidant system plays a role in degradation of reactive oxygen species. Magnetized water forms smaller stabilizing water clusters, resulting in high absorption and permeability of the cell for water, implicating its application for semen preservation. Therefore, this review focuses on preservation methods of boar and bull semen with respect to improvement of extender and reduction of reactive oxygen species by using magnetized water and supplementation of antioxidants.

• 한국통신학회논문지
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• 제37권6B호
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• pp.443-452
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• 2012

Mobile Ad-hoc Networks 환경에서 노드의 이동성을 고려하기 위한 라우팅 알고리즘은 그 특성에 따라 Proactive와 Reactive 방식으로 구분되며, 두 가지 라우팅의 장점을 조합하는 많은 Hybrid 라우팅이 ZRP (Zone Routing Protocol) 알고리즘을 기반으로 설계되어왔다. ZRP는 특정 지역의 Zone을 생성한 후, Zone 내부에는 Proactive, 외부에는 Reactive 방식을 운영하여 근거리 노드들을 향하는 데이터의 경로 탐색 패킷 발생의 비용을 최소화 하였다. 하지만 실제 네트워크에서의 데이터 전송은 짧은 시간 영역에서 특정 노드에게만 요구되는 경향이 있으며, 이에 대한 고려가 없는 ZRP는 이러한 요구를 만족시키기에는 제한적이다. 본 연구는 실시간 데이터 전송량과 전송 경로의 홉 수를 고려하여, 소스 노드와 목적지 노드를 근간으로 하는 Zone을 on-demand로 형성하는 효율적인 Hybrid 라우팅을 제안하고, 이를 위하여 Zone의 생성 및 소멸을 결정하는 DZD (Dynamic Zone Decision) 알고리즘을 고안한다. 또한, 본 연구의 성능을 검증하기 위하여 기존의 Proactive, Reactive, Hybrid 라우팅 알고리즘과의 비교결과를 분석하였다.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.369-369
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• 2006

Compatibilizers contribute to many processes in polymer industry, such as manufacturing polymer blends and composites. They are usually designed to be block or graft form which is combined in polar and non-polar parts in the first synthesis process level, for example, the general form of maleic anhydride (MA) as a compatiblizer is a grafted counterpart. However, the process of making the compatibilizer is related to the first synthesis level and it has some problems, such as high cost, poor processability, limitation on use and properties, and so on. So, in order to improve its poor processability and overcome the limitation on use, we developed compatibilizers which have various chemical forms by high intensity ultrasound and super critical fluid nitrogen in polymer melt reactive extrusion.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제13권2호
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• pp.73-86
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• 2009

The problem of thermal stability of an exothermic reactive viscous fluid between two parallel walls in the plane Poiseuille and Couette flow configurations is investigated for different thermal boundary conditions. Neglecting reactant consumption, the closed-form solutions obtained from the momentum equation was inserted into the energy equation due to dissipative effect of viscosity. The resulting energy equation was analyzed for criticality using the variational method technique. The problem is characterized by two parameters: the Nusselt number(N) and the dynamic parameter($\Lambda$). We observed that the thermal and dynamical boundary conditions of the wall have led to a significant departure from known results. The influence of the variable pre-exponential factor, due to the numerical exponent m, also give further insight into the behavior of the system and the results expressed graphically and in tabular forms.