• 한국식품과학회지
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• 제18권5호
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• pp.364-371
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• 1986

High-ester pectin을 HCI 단독 또는 HCI 과 $NH_4OH$를 병용하여 demethylation 시킨뒤 얻어진 low-ester pectin(LM pectin)으로 gel을 제조하였다. LM pectin gel의 단단함과 강도(强度)를 측정한 결과 HCI로 처리된 LM pectin gel은 일반적으로 강도(强度)가 약하고 거칠며 탄력이 없었다. 반면 $HCl-NH_4OH$로 처리한 LM pectin gel은 텍스쳐가 부드럽고 탄력이 좋았다. 물리적 성질에 대한 LM pectin의 화학적 조성의 상관 관계에서 단단함(Sag값)에 대한 ester함량 및 분자량, 그리고 강도(强度)(puncture stress)에 대한 amide 및 ester함량 EH는 분자량 간에는 유의성 있는 관계가 밝혀졌다. 상관성이 높은 화학적 인자에서 LM pectin gel의 물리적 성질을 예측할 수 있는 관계식을 산출하였다.

• 한국식품과학회지
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• 제23권2호
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• pp.217-223
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• 1991

Gel식품의 구조적 특성을 밝히는 일은 특수한 장치나 분석방법이 요구되어 왔으나 본 연구에서는 조작이 간편하고 확산식에 잘 맞는 농도의 해를 구할 수 있는 capillary method를 통해 확산량과 확산계수를 예측하였다. 확산량은 거리, 시간, agar% 농도를 독립변수로 하여 도시하고 추정된 몇 가지 함수식으로부터 SPSS 통계 package 중 regression program을 이용해 단순회귀시켜 R-square가 가장 높은 식을 채택하고 다시 각 독립변수에 대한 함수식을 이용해 다중회귀분석을 실시함으로써 최종 model식을 수립하였다. 기존의 확산계수 예측방법은 Fick의 제 2법칙의 해식으로부터 예측되는 것이 일반적이었으나 그 식이 난해하고 시간이 많이 걸려 본 연구에서는 좀 더 간편한 방법으로 확산계수를 구하고자 수치해석적 방법에 따라 확산계수를 예측하였으며 그 산술평균을 확산계수 D값으로 나타내었다.

• 한국응용과학기술학회지
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• 제38권1호
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• pp.300-308
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• 2021

본 연구에서는 3차원 네트워크 폴리아크릴산나트륨 겔의 가교환경을 변화시켜 기계적 강도 및 팽윤거동을 제어하고 그 물성을 평가하는 연구를 진행하였다. 일반적으로 겔 용액의 가교도가 증가함에 따라 3차원 네트워크 겔의 팽윤비는 감소하고 겔의 기계적 강도는 증가한다. 본 연구에서는 3차원 네트워크 겔 상의 가교개수밀도를 산출하여, 겔화 과정에서 가교환경에 의존하는 중합효율 및 가교효율을 확인하였다. 그 결과, 겔 용액에서 단량체와 가교제의 중량비가 동일하더라도 가교환경이 달라지면 실제 제조된 겔 내부의 가교개수밀도가 3.6배 이상 달라질 수 있음을 확인하였다. 본 연구에서 시도한 가교개수밀도 기반 겔 평가 방법을 활용하면 효과적인 VOCs 흡수제로써 3차원 네트워크 겔을 최적화 할 수 있으리라 기대된다.

• Journal of Dental Anesthesia and Pain Medicine
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• 제21권4호
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• pp.329-336
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• 2021

Background: In the field of dentistry, topical anesthetics play an important role in reducing pain during needle pricks. The anesthetic property of betel leaves remain unexplored, even though they have been widely used for the treatment of various ailments. The purpose of this study was to compare and evaluate pain perception following topical application of lignocaine gel, clove gel, ice, and newly developed betel leaf extract gel during intraoral injection in children. Methods: Sixty children aged 6-10 years who met the inclusion criteria were divided into four groups. Topical anesthetic agents, 2% lignocaine (Lox-2% Jelly, Neon, Mumbai, India), 4.7% clove gel (Pain Out Dental Gel, Colgate Palmolive India Ltd, Solan, India), 10% betel leaf extract gel, and ice were applied to each group for one min, followed by administration of infiltration anesthesia. Pain perception was analyzed during needle insertion. The Wong Bakers FACES pain rating scale (WBFPRS) was used for subjective assessment and the Sound, Eye, Motor (SEM) scale for objective assessment. Recorded values were tabulated and subjected to appropriate statistical analysis using SPSS software with a P value set at 0.05. Results: The clove oil and betel leaf groups demonstrated the highest WBFPRS scores, followed by the ice and lignocaine groups. The clove, betel leaf extract, and ice groups showed equal and highest SEM scores, followed by the lignocaine group. The mean WBFPRS and mean SEM scores were statistically significant. Conclusion: Betel leaf extract gel is effective in reducing pain and can act as an alternative topical anesthetic agent.

• Journal of Microbiology
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• 제45권6호
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• pp.515-520
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• 2007

Vaginal lactic acid-producing bacteria of 80 pre-menopausal women were studied by isolation on Blood and DeMan-Rogosa-Sharpe agar, PCR with group-specific primers for Lactobacillus-denaturing gradient gel electrophoresis (DGGE), and PCR with specific primers for V3 region in 16S rRNA-temporal temperature gel electrophoresis (TTGE). Conventional isolation method on media detected only one lactobacillus (Lactobacillus brevis) while TTGE detected only Lactobacillus sp. DGGE detected seven Lactobacillus species; L. coleohominis, L. crispatus, L. iners, L. reuteri, L. rhamnosus, L. vaginalis, and Leuconostoc lactis. L. acidophilus and L. gasseri, which are prevalent in Western women, were not detected in Korean women. Furthermore, L. rhamnosus, Leuc. lactis, L. coleohominis, and Weissella cibaria, which were not previously reported in the vaginal microbiota of Korean women, were detected. The five most prevalent LABs in vaginal microbiota in Korean women were L. iners, Enterococcus faecalis, L. crispatus, Leuc. lactis, and W. cibaria.

• 한국환경성돌연변이발암원학회지
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• 제17권2호
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• pp.71-77
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• 1997

The single cell gel electrophoressis(SCGE) assay, also known as the comet assay, is a rapid, simple, visual and sensitive technique for measuring and analysing DNA breakage in mammalian cells. The SCGE or comet assay is a promising test for the detection of DNA damage and repair in individnal cells. It has widespread potential applications in DNA damage and repair studies, genotoxicity testing and biomonitoring. In this microgel electrophoresis technique, cells are embedded in agarose gel on microscope slides, iysed and electrophoresed under alkaline conditions. Cells with increased DNA damage display increased migration of DNA from the nucleus towards the anode. The length of DNA migration indicates the amount of DNA breakage in the cell. The comet assay is also capable of identifying apoptotic cells which contain highly fragmented DNA. Here we review the development of the SCGE assay, existing protocols for the detection and analysis of comets, the relevant underlying principles determining the behaviour of DNA and the potential applications of the technique.

• International Journal of Industrial Entomology and Biomaterials
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• 제14권1호
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• pp.37-44
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• 2007

A study was made of the haemolymph protein spectrum of mulberry silkworm (Bomhyx mori L.) from the first larval instar to imago. Horizontal starch gel electrophoresis was used. Sixteen races and eight F1 interracial hybrids, raised in Bulgaria, were analyzed. During the ontogenesis, a total of 17 protein bands (15 cathodic and 2 anodic) were detected. Distinct dynamics in the haemolymph protein spectrum was observed, in result of different expression during the individual development associated with the processes of growth, histolysis and histogenesis. Based on the ontogenetic dynamics found, a correspondence was assumed between some proteins detected by us using the starch gel electrophoresis and major haemolymph proteins (SP1, SP2, MHPs and Vg) detected by other authors using the polyacrilamide gel electrophoresis. Intraracial and interracial polymorphism was observed in four protein zones. The effect of four polymorphic loci with codominant and null alleles was suggested.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.245-246
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• 2006

A propyl alcohol based sol-gel method was used as to replace the 2-methoxyethanol with 1,1,1 tris (hydroxymethyl) ethane for preparation of pzt piezoelectric ceramic. The powder obtained by this sol-gel process were calcined at $900^{\circ}C$ and followed by the sintering at $1100^{\circ}C$ for ca2 hrs as to reach a pyrochlore-free crystal phase. The characterization of synthesized material was carried out by the XRD analysis and the surface morphology were determined by high resolution scanning electronmicroscopy. Further, the prepared small sized pzt thin powders are likely to be used m various applications.

• 한국세라믹학회지
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• 제30권7호
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• pp.571-577
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• 1993

The effect of $\alpha$-Al2O3 seeding on preparation of zirconia/alumina gel fragment prepared by sol-gel processing was characterized through XRD, SEM, TG/DTA and IR analysis. Aluminum isopropoxide and zirconium butoxide were used as starting materials. $\alpha$-Al2O3 seeding restrained grain growth of alumina and zirconia, and decreased tetragonal to monoclinic phase transformation of zirconia on cooling. Therefore, fine zirconia-toughened alumina composite having the relative sintered density of about 98% of theoretical at 140$0^{\circ}C$ for 2h could be obtained.

• 한국세라믹학회지
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• 제30권2호
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• pp.115-122
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• 1993

Transparent Al2O3 and TiO2 clear sols prepared by hydrolysis and subsequent peptization were mixed into wet gel. EDS analysis for this gel showed that wet gel was extremely homogeneous in chemical composition. Calcination of the wet gel at 120$0^{\circ}C$ for 50 minutes resulted in Al2O3-TiO2 nanocomposite powders where TiO2 particles of 101~102 nanometer were dispersed in the Al2O3 matrix. Both powders were sintered for 4 hours in the temperature range over 1500~1$650^{\circ}C$ with and without 5wt% MgO sintering aid. Among these sintered bodies, nanocomposite powder compacts sintered at 1$650^{\circ}C$ for 4 hours with 5wt% MgO showed the most dense structure with the grain size under 5${\mu}{\textrm}{m}$ and highest relative density of 98.2%.