• Title/Summary/Keyword: Gem

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Spectroscopic analysis of near colorless/pink/blue synthetic diamonds from Lightbox ('라이트박스' 무색/핑크/블루 합성 다이아몬드의 분광학적 분석)

  • Choi, Hyunmin;Kim, Youngchool;Lee, Minkyoung;Seok, Jeongwon
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.30 no.1
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    • pp.21-26
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    • 2020
  • This article reports the result on the spectroscopic analysis of the three Lightbox CVD-grown diamonds. Lightbox Jewelry, a De Beers company, has begun selling CVD laboratory-grown diamonds since September 2018. Recently, we had the opportunity to examine three Lightbox's pendant necklaces. The 0.25 ct, 0.25 ct, and 0.26 ct round brilliant were graded as "H" near colorless, Fancy Vivid orangy pink, and Fancy Vivid blue with cut grades of excellent, respectively. The laser-inscribed Lightbox logo under the table, large enough to be easily visible with a microscope. Based on the spectroscopic techniques, for near colorless sample was not subjected to post-growth HPHT processing to improve its color. For pink sample, optical centers at H3, 3H, 594 nm, NV, and GR1 were recorded. It was speculated that the pink sample have been received irradiation and annealing. In addition, the blue CVD synthetic sample was concluded to be irradiated without annealing.

Evaluation of Self-Healing Performance Using Hydration Model of Portland Cement and Clinker (포틀랜드시멘트와 클링커의 수화모델을 이용한 자기치유 성능평가)

  • Choi, Sang-Hyeon;Park, Byoung-Sun;Cha, Soo-Won
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.8 no.1
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    • pp.81-87
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    • 2020
  • Crack control is essential to increase the durability of concrete significantly. Healing of crack can be controlled by rehydration of unreacted clinkers at the crack surface. In this paper, by comparing the results of isothermal calorimetry test and regression analysis, the Parrot & Killoh's cement hydration model was verified and clink er hydration model was proposed. The composition and quantification of hydration products were simulated by combining kinematic hydration model and thermodynamic model. Hydration simulation was conducted using the verified and proposed hydration model, and the simulation was performed by the substitution rate of clink er. The type and quantity of the final hydration product and healing product were predicted and, in addition, the optimal cementitious material of self-healing concrete was selected using the proposed hydration model.

Construction of a Recombinant Leuconostoc mesenteroides CJNU 0147 Producing 1,4-Dihydroxy-2-Naphthoic Acid, a Bifidogenic Growth Factor

  • Eom, Ji-Eun;Moon, Gi-Seong
    • Food Science of Animal Resources
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    • v.35 no.6
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    • pp.867-873
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    • 2015
  • 1,4-Dihydroxy-2-naphthoic acid (DHNA), a precursor of menaquinone (vitamin K2), has an effect on growth stimulation of bifidobacteria and prevention of osteoporosis, making it a promising functional food material. Therefore, we tried to clone the menB gene encoding DHNA synthase from Leuconostoc mesenteroides CJNU 0147. Based on the genome sequence of Leu. mesenteroides ATCC 8293 (GenBank accession no., CP000414), a primer set (Leu_menBfull_F and Leu_menBfull_R) was designed for the PCR amplification of menB gene of CJNU 0147. A DNA fragment (1,190 bp), including the menB gene, was amplified, cloned into pGEM-T Easy vector, and sequenced. The deduced amino acid sequence of MenB (DHNA synthase) protein of CJNU 0147 had a 98% similarity to the corresponding protein of ATCC 8293. The menB gene was subcloned into pCW4, a lactic acid bacteria - E. coli shuttle vector, and transferred to CJNU 0147. The transcription of menB gene of CJNU 0147 (pCW4::menB) was increased, when compared with those of CJNU 0147 (pCW4) and CJNU 0147 (−). The DHNA was produced from it at a detectable level, indicating that the cloned menB gene of CJNU 0147 encoded a DHNA synthase which is responsible for the production of DHNA, resulting in an increase of bifidogenic growth stimulation activity.

About Korean Precious Metal Industrial Activation Plan Research (With a Focus on Synthetic Gem) (한국 귀금속산업 활성화 방안분석(CAD/CAM을 중심으로))

  • Park, Seung-Chul
    • The Journal of the Korea Contents Association
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    • v.9 no.12
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    • pp.613-621
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    • 2009
  • Except for traditional industrial art and history of design development, Korea jewelry industry before 1980's, had little meaning in the aspect of marketing and business. Domestic jewelry market which have changed from the value of goods to value of ornaments, faced important transition point for jewelry industry by the chance of in Asian Game held in 1986, and money of overseas traveler after 1980s. The rapidly-grown Jewelry field by the introduction of detail casting method to make it possible mass-production of the products before 1990's, began to change into new system, with introducing CAD/CAM after 1990's. Jewelry industry has changed from manual work called handmade to the detail casting industry based on master for mass-production. For this, the development of master, with the design development, have been suggested as important task to jewelry industry firms, and by the introduction of CAD/CAM, the diversification of design and master development has been made up. In this study, we would try to find out current status of domestic jewelry field and to understand CAD/CAM, and advantage of CAD/CAM, and through this, suggest good solution to precipitate domestic jewelry market.

Identification of Entomopathogenic Fungus, Beauveria spp. F-101 Isolated from Thecodiplosis japonensis Using Internal Transcribed Spacer Sequence

  • Shin, Sang-Chul;Roh, Jong-Yul;Kim, Chul-Su;Park, Il-Kwon;Jeon, Mun-Jang;Je, Yeon-Ho
    • International Journal of Industrial Entomology and Biomaterials
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    • v.8 no.1
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    • pp.77-80
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    • 2004
  • For the development of the alternative control system against the major forest pests, Beauveria spp. F-101, isolated from a dead larva of Thecodiplosis japonensis, was selected because this isolate showed high pathogenicities against T. japonensis and Acantholyda parki. Beauveria spp. F-101 had irregular clustered conidio-phores and conidia borne on a distinctive apical zigzag extension, and it showed typical characteristic of the genus, Beauveria in morphology. For molecular based-identification, the ribosomal ITS region of Beauveria spp. F-101 was amplified with ITS1 and ITS4 primers, and cloned into pGEM- T Easy vector. The amplified PCR product was 569 bp in size and completely sequenced. The similarities of the cloned ITS sequence were 99 % and 97% to those of B. bassiana and B. brongniartii, respectively. In comparison to other species among the genus Beauveria, the ITS region of Beauveria spp. F-101 showed a similarity of 95% to B. amorpha, 95% to B. tenella, 89% to B. vermiconia and 69% to B. alba, respectively. In addition, in comparison to different genus, it had 95% similarities to Cordyceps militaris and 91% to Paecilomyces tenuipes. Accordingly, the current result suggests that Beauveria spp. F-101 was a variant of B. bassiana and it seems to be a new isolate considering sequence variation in ITS region.

The analysis of optical influence on the grading tolerances and proportions for the round brilliant cut polished diamonds (Round brilliant cut으로 연마한 diamond의 등급별 허용 오차와 proportions에 관한 광학적 영향력 분석)

  • Kim, Eun-Ju
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.23 no.4
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    • pp.173-179
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    • 2013
  • Even though a rough diamond shape is irregular and rugged, it is easy to be processed to make gem, shaped facets (table, crown, pavilion and girdle) were precisely treated because they influence on the evaluation of diamond grading. Those specifications suitable for the standard round brilliant cut diamond polishing were investigated and in 95 % statistical confidence interval, standard deviation, mean and acceptable tolerance were examined. According to these variables (size, angle, depth, and thickness) distribution, the frequency analysis of ratings and proportions were compared with each other. The correlation between each variables and the evidence of influence represented in proportion were determined by the regression analysis applying LSM (Least Square Method). In this research, it was recognized that table sizes of the diamond jewels and pavilion depth (in %) influence the rating decision and in particular, the depth of pavilion acting as the main factor of proportions, also plays an important role in optical phenomena.

Membrane Transporter Genes in Cephabacin Biosynthetic Gene Cluster of Lysobacter lactamgenus

  • Nam, Doo-Hyun;Lim, Si-Kyu;Chung, Min-Ho;Lee, Eung-Seok;Sohn, Young-Sun;Dewey, D.Y. Ryu
    • Journal of Microbiology and Biotechnology
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    • v.11 no.1
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    • pp.153-159
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    • 2001
  • In order to clone the peptide synthetase gene form Lysobacter lactamgenus IFO 14,288, the gene fragments were amplified using primers for the adenylation domain and the thionylation domain of the peptide synthetase genes in other organisms by polymerase chain reaction (PCR). The resulting 0.5-kb fragment was cloned in a pGEM-T vector, and the nucleotide sequences were determined. Six different PCR products were obtained; three were identified to be a part of L-$\alpha$-aminoadipyl-L-cysteinyl-D-valine (ACV) synthetase and three to be other peptide synthetases. Using each of the two different classes of PCR products as mixed probes, a cosmid library of L. lactamgenus chromosomal DNA constructed in a pHC79 vector was screened by an in situ hybridization procedure, and one positive clone was selected which was bound by peptide synthetase gene fragments as well as ACV synthetase gene fragments. The partial sequence analysis formt he obtained pPTS-5 cosmid showed th presence of more than two open reading frames. These were for two putative membrane transporters, which were homologous with several integral membrane proteins including the ABC transporter ATP-binding protein of E. coli (YbjZ) and the metal ion uptake protein of Bacillus subtilis (YvrN). A 45% homology was also found between the two transporter proteins at the carboxy terminus. Through a hydropathy analysis and transmembrane analysis. 4-5 transmembrane domains were found in these two proteins. When the genes were expressed in Escherichia coli, the gene products inhibited the hose cell growth, probably due to the disturbance of the membrane transport system.

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Occurrence of Apple scar viroid-Korean strain (ASSVd-K) in Apples Cultivated in Korea

  • Lee, Ju-Hee;Park, Jean-Kyung;Lee, Dong-Hyuk;Uhm, Jae-Youl;Ghim, Sa-Youl;Lee, Jai-Youl
    • The Plant Pathology Journal
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    • v.17 no.5
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    • pp.300-304
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    • 2001
  • Apple is the most economically important fruit in Korea. The suspected viroid disease of dapple apple was found in apple fruits cultivated in Kyungpook province. Symptoms begin in mid-July as small circular spots, which stand out against the background color on the young fruit. Dappling of the fruit becomes more intense and easier to detect as the fruit approaches maturity; the affected spots remain yellowish as the fruit matures. no leaf or bark syndromes have been associated with this disease. The infected fruits are downgraded considerably during quality grading. The low molecular weight RNA containing viroid RNA molecules were extracted from the peels of the apples with dapple symptoms. The RNA molecules were extracted from the apples using Qiagen column chromatography. The purified RNAs were used for the synthesis of cDNA with RT-PCR. The PCR products were then ligated into a pGEM-T Easy vector, cloned and sequenced. The sequence of the viroid RNA molecule shows 331 nucleotides with one base difference ("G" insertion between the position of 133 and 134) compared with that of the Apple scar skin viroid (ASSVd) reported by Hashimoto and Koganezawa in Japan. This is the first report on the occurrence of the ASSVd in apple trees cultivated in Korea, as well as the identification of a new Korean strain of the ASSVd.the ASSVd.

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Clonorchis sinensis tropomyosin: Cloning and sequence of partial cDNA amplified by PCR (간흡충 tropomyosin: PCR로 일부분 증폭된 cDNA의 cloning 및 염기서열)

  • 홍성종
    • Parasites, Hosts and Diseases
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    • v.31 no.3
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    • pp.285-292
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    • 1993
  • C. sinensis total RMh was containing large amount of 185 rRNA but little 285 rRNA. The size of the double-stranded cDNA synthesized from poly $(A)^{+}$ mRNA was 0.4-4.2 kb long with tapering unto 9.5 kb. Degenerated oligonucleotides (as 2 sense and 3 antisense Primers) were designed on the conserved regions of the known tropomyosin amino acid sequences. From one out of the PCR amplifications using total CDNA and matrix of primers, a specific gene product, 580 bp in size, was produced. Upon Southern hybridization of the PCR products with Schistosomn mnnsoni tropomyosin (SMTM) CDNA, only one signal appeared at the band of 580 bp product. This 580 bp product was considered to encode C. sinensis tropomyosin (CSTM) and cloned in pGEM-3Zf(-) for DNA sequencing. CSTM cDNA was 575 bp containing one open reading frame of 191 predicted amino acids, which revealed 86.3% homology with SMTM and 51.1% with rrichostronsylur coeubnlormis tropomyosin. CSTM cDNA obtained will serve as a probe in the studies of molecular cloning of CSTM.

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Development of Feature Points Detection Algorithm for Measuring of Pulse Wave Velocity (맥파 전달 속도(PWV) 측정을 위한 특징점 검출 알고리즘 개발)

  • Choi, Jung-Hyeon;Cho, Wook-Hyun;Park, Jun-Ho;Kim, Nam-Hoon;Seong, Hyang-Sook;Cho, Jong-Man
    • Journal of Sensor Science and Technology
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    • v.20 no.5
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    • pp.343-350
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    • 2011
  • The compliance and stiffness of artery are closely related with disease of arteries. Pulse wave velocity(PWV) in the blood vessel is a basic and common parameter in the hemodynamics of blood pressure and blood flow wave traveling in arteries because the PWV is affected directly by the conditions of blood vessels. However, there is no standardized method to measure the PWV and it is difficult to measure. The conventional PWV measurement has being done by manual calculation of the pulse wave transmission time between coronary arterial proximal and distal points on a strip chart on which the pulse wave and ECG signal are recorded. In this study, a pressure sensor consisting of strain gauges is used to measure the blood pressure of arteries in invasive method and regular ECG electrodes are used to record the ECG signal. The R-peak point of ECG is extracted by using a reference level and time windowing technique and the ascending starting point of blood pressure is determined by using differentiation of the blood pressure signal and time windowing technique. The algorithm proposed in this study, which can measure PWV automatically, shows robust and good results in the extraction of feature points and calculation of PWV.