• 제목/요약/키워드: cure characteristics

검색결과 314건 처리시간 0.026초

Oral and Human Microbiome Research

  • Chung, Sung-Kyun
    • 치위생과학회지
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    • 제19권2호
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    • pp.77-85
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    • 2019
  • In the past gut microbiome has been the main focus of microbiome research. Studies about the microbiome inside oral cavities and other organs are underway. Studies about the relationship between noninfectious diseases and periodontal diseases, and the negative effects of harmful oral microbes on systemic health have been published in the recent past. A lot of attention is being paid towards fostering a healthy oral microbial ecosystem. This study aimed to understand the roles and effects of the microbiome inside the human body can potentially help cure various diseases including inflammatory bowel diseases with no known cure such as Crohn's disease, atopic dermatitis, obesity, cancer, diabetes, brain diseases and oral diseases. The present study examined technological trends in the correlation between the human microbiome and diseases in the human body, interactions between the human body's immunity, the metabolic system, and the microbiome, and research trends in other countries. While it has been proven that human microbiome is closely correlated with human diseases, most studies are still in the early stage of trying to compare the composition of microbiomes between health and patient groups. Since the oral environment is a dynamic environment that changes due to not only food intake but also other external factors such as lifestyle, hygiene, and drug intake, it is necessary to continue in-depth research on the microbiome composition characteristics to understand the complex functions of oral microorganisms. Analyzing the oral microbiome using computational technology may aid in disease diagnosis and prevention.

Effect of Silica Nanoparticles on Tear Strength of CR Compounds: A Comparison Study between the ASTM D470 and DIN VDE 0472-613

  • Changsin Park;Byeong-Rea Son;Gi-Bbeum Lee;Changwoon Nah
    • Elastomers and Composites
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    • 제59권1호
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    • pp.34-41
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    • 2024
  • In this study, the effects of the type and content of silica on the mechanical and tear properties of chloroprene rubber (CR), which is mainly used as a jacket material for mining cables, were studied. The crosslinking density (ΔM) and reinforcing factor (αf) defined using cure characteristics increased with increasing silica content, whereas the cure rate decreased. The hardness, tensile strength, and modulus of the CR compounds increased depending on the silica content and structural development. The reinforcing behavior of the silica-filled CR compounds according to the silica type and content showed the best fit with the Thomas equation of the predictive model. Tear strength was evaluated using two standard test methods, ASTM D470 and DIN VDE 0472-613, and the results were compared. The tear strength increased as the silica content increased, regardless of the test method, and the different tear strengths obtained by the two standard test methods showed a linear relationship with each other, indicating a high correlation.

Dynamic percolation grid Monte Carlo simulation

  • Altmann Nara;Halley Peter J.;Nicholson Timothy M.
    • Korea-Australia Rheology Journal
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    • 제19권1호
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    • pp.7-16
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    • 2007
  • A dynamic Monte Carlo percolation grid simulation is used to predict the cure behaviour of thermoset materials. Molecules are distributed in a fixed grid and a probability of reaction is assigned to each pair of neighbouring units considering both reaction rates and diffusion. The concentration and network characteristics are predicted throughout the whole curing process and compared to experimental data for an epoxy-amine matrix.

철도차량의 차륜마모 저감 (Wheel flange Wear Reduction of Rolling Stock)

  • 허현무;이찬우
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2000년도 춘계학술대회 논문집
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    • pp.143-150
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    • 2000
  • Like conventional railways, improving running performance of vehicle in curve is more effective than improving maximum speed to reduce traveling time. But some vehicles have problems concerning running performance in cure because of insufficient study for our conventional railway characteristics. So, these problems brought about increasement of maintenance cost. This study was started to deliberate several plans to solve problems concerning running performance in curve. Some modifications of primary suspension and tests were carried out to improve curve negotiation. Here, we describe some results.

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혼합 에폭시 수지의 전기 절연특성 (Electrical Insulating Characteristics of Mixing Epoxy Resin)

  • 홍경진;정우성;이은학;김태성
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1990년도 추계학술대회 논문집
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    • pp.95-97
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    • 1990
  • This study investigated electrical characteristic of solids and liquid epoxy resins by measuring dielectric breakdown and dielectric loss when epoxy resins were exposed to a mixing cure. It was found that mixing epoxy resins were superior to dielectric breakdown and hardness and has shorter curing time compare with those of pure liquid epoxy resins.

Pharmacognostical Studies on the Folk Medicine 'Bong Seon Wha Dai'

  • Park, Jong-Hee;Kim, Jeong-Myo;Kwon, Dae-Kun
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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    • pp.270.2-270.2
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    • 2003
  • Korean folk medicine ‘Bong Seon Wha Dai’ has been used to cure constipation and acute gastritis by meat. The botanical origin of the crude drug has never been studied pharmacogostically. To clarify the botanical origin of Bong Seon Wha Dai. the morphological and anatomical characteristics of Impatiens species growing in Korea, i.e. I. balsamina L., I. noli-tangere L.. I. textori Miq., I. textori Miq. forma. pallenscens Hara were studied. (omitted)

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Therapeutic evaluation of sustained-releasing praziquantel (SRP) for clonorchiasis: Phase 1 and 2 clinical studies

  • Choi, Min-Ho;Chang, Byung-Chan;Lee, Seung-Jin;Jang, In-Jin;Shin, Sang-Goo;Kho, Weon-Gyu;Chun, Jin-Ho;Hong, Sung-Tae
    • Parasites, Hosts and Diseases
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    • 제44권4호
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    • pp.361-366
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    • 2006
  • Sustained-releasing praziquantel (SRP) tablet was designed for single dose treatment regimen of clonorchiasis. A previous pre-clinical study confirmed its sustained-releasing characteristics and a better cure rate than conventional praziquantel (PZQ). In this clinical study, the pharmacokinetics of this SRP tablet were investigated in human volunteers (phase 1; 12 volunteers), and its curative efficacy was examined in clonorchiasis patients (phase 2; 20 volunteers). In the phase 1 clinical study, blood concentrations of both tablets showed wide individual variation. The $AUC_{last}$ of SRP was $497.9{\pm}519.0ng{\cdot}hr/ml\;(mean{\pm}SD)$ and PZQ of $628.6{\pm}695.5\;ng{\cdot}hr/ml$, and the $AUC_{inf}$ of SRP was $776.0{\pm}538.5\;ng{\cdot}hr/ml$ and of PZQ $658.6{\pm}709.9\;ng{\cdot}hr/ml$. $C_{max}$ values of SRP and PZQ were $90.7{\pm}82.2ng/ml\;and\;214.9{\pm}251.9\;ng/ml$, and $T_{max}$ values were $3.42{\pm}1.43\;hr\;and\;1.96{\pm}1.23\;hr$, respectively. SRP tablets showed similar AUC values, but lower $C_{max}$ and longer $T_{max}$ values than PZQ. In the phase 2 study, SRP at 30 mg/kg (single dose) achieved a 60% cure rate and a 95.5% egg reduction rate. The cure rate of a single dose SRP was unsatisfactory compared with that of the conventional PZQ dose, but much better than that achieved by a single dose PZQ.

치환기 변화에 따른 열잠재성 양이온 촉매의 합성과 잠재특성 연구 (Synthesis and Latent Characteristics of Thermal Cationic Latent Catalysts by Change of Substituent)

  • 박수진;허건영;이재락;심상연;서동학
    • 폴리머
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    • 제25권4호
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    • pp.558-567
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    • 2001
  • 피라진염의 치환기를 변화시킨 열잠재성 양이온 촉매를 합성하고, 이관능성 에폭시(diglycidylether of bisphenol-A, DGEBA)에 개시제로서 1 wt% 촉매를 혼합하여 동적 DSC방법을 이용한 경화 거동과 열잠재 특성에 대해 연구하였다. 그 결과 합성된 촉매들은 에폭시 시스템에서 우수한 열잠재성을 가지고 있음을 확인하였다. 치환기의 염기도(basicity)가 높을수록 경화온도와 활성화 에너지는 높아지고 활성은 낮아졌는데 이는 활성과 경화거동이 링 스트레인(ring strain) 및 도입된 치환기의 염기도(basicity)에 의해 조절되기 때문인 것으로 사료된다. 결론적으로, 전자공여 그룹인 메틸기를 도입한 촉매의 활성은 경화시 개시단계에서 염기도 증가로 인한 피라진의 이탈능과 벤질 양이온의 안정성이 감소되었기 때문에 낮아졌으며, 전자수용 그룹인 시아노기를 도입한 촉매의 활성은 유기효과와 공명에 인해서 벤질 양이온의 안정성이 증가됨으로써 높아졌다.

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경화 압력이 접착 조인트의 비틀림 피로 특성에 미치는 영향 (Effects of the curing pressure on the torsional fatigue characteristics of adhesively bonded joints)

  • 황희윤;김병중;이대길
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.196-201
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    • 2004
  • Adhesive joints have been widely used for fastening thin adherends because they can distribute the load over a larger area than mechanical joints, require no hole, add very little weight to the structure and have superior fatigue resistance. However, the fatigue characteristics of adhesive joints are much affected by applied pressure during curing operation because actual curing temperature is changed by applied pressure and the adhesion characteristics of adhesives are very sensitive to manufacturing conditions. In this study, cure monitoring and torsional fatigue tests of adhesive joints with an epoxy adhesive were performed in order to investigate the effects of the applied pressure during curing operation. From the experiments, it was found that the actual curing temperature increased as the applied pressure increased, which increased residual thermal stress in the adhesive layer. Therefore, the fatigue life decreased as the applied pressure increased because the mean stress during fatigue tests increased due to the residual thermal stress.

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Curing Characteristics of Low Molar Ratio Urea-Formaldehyde Resins

  • Fan, Dongbin;Li, Jianzhang;Mao, An
    • 접착 및 계면
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    • 제7권4호
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    • pp.45-52
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    • 2006
  • Five low molar ratio urea-formaldehyde (LUF) resins were synthesized in this study. The effects of molar ratio, free formaldehyde content, and catalysts on the curing characteristics of LUF resins were studied by measuring its free formaldehyde content, pH value change after catalysts added, curing rate, and pot life, observing its cured appearance, and analyzing its thermal behavior. The results indicate that: 1) The LUF resin with lower molar ratio than 1.0 can still cure; 2) Free formaldehyde content is not the main factor in affecting curing rate of LUF resin; 3) Compared with ammonium chloride as a traditional catalyst, persulfate salts markedly accelerate the curing rate of LUF resin, and result in the different appearance; 4) the addition of sodium chloride to catalysts can accelerate the curing rate of LUF resin, but the effect is moderate.

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