• Title/Summary/Keyword: trans

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The trans Effect of Ligands on the Calculated Dipole Moments for Square Planar $[Pt(II)Cl(PEt_3)_2X]$ The Complexes (X = H, Methyl and Phenyl Group (사각형 $[Pt(II)Cl(PEt_3)_2X]$형태 착물의 계산한 쌍극자모멘트에 대한 리간드의 trans 효과 (X = H, Methyl, Phenyl Group))

  • Sangwoon Ahn;Dong Heu Kim;Euisuh Park
    • Journal of the Korean Chemical Society
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    • v.28 no.1
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    • pp.3-13
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    • 1984
  • The trans effect of ligands on the calculated dipole moments has been investigated, choosing trans square planar $[Pt(II)Cl(PEt_3)_2X]$ type complexes. The calculated dipole moments decrease in the order H > Me > Ph > Cl which is the same as the order of decreasing the experimental dipole moments. This order is in agreement with the order of decreasing the trans effect as determined by rate of reaction. The calculated dipole moments for cis complexes are markedly higher than those for trans complexes. This is also in agreement with experimental fact. The calculated dipole moments for some of cis complexes are, however, lower than the observed values, which is different from trans complexes.

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Ab initio Calculation for Photochemistry of Psoralens (소랄렌의 광화학 반응에 대한 Ab initio 계산)

  • Kim, Ja-Hong;Kwon, O-Hyung
    • Journal of the Korean Chemical Society
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    • v.53 no.3
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    • pp.244-256
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    • 2009
  • The psoralen-pyrimidine base complexes resulting from interstrand cross-linking through $C_4$-cycloaddition is studied by ab initio and DFT methods. The results indicate that in the case of the molecular complex formation between psoralens and pyrimidine base, the most probable photocycloadditions are 8-MOP< >Thy, Ps< >Cyt and Ps< >Thy. The geometries of photoadducts were optimized at the HF levels and ${\Delta}{G^{\circ}}$ were calculated. The photocycloadduct was inferred to be a C4-cycloaddition product with the stereochemistry of trans-syn 8-MOP< >Thy, trans-anti Ps(3, 4)< >Cyt, trans-anti Ps(12, 13)< >Cyt, trans-syn Ps(3, 4)< >Thy, trans-syn Ps(12, 13)< >Thy, trans-anti Ps(12, 13)< >Ps(12, 13), cis syn, cis anti Thy< >(3, 4)Ps(12, 13)< >Thy.

Pressure Effect on the Aquation of trans-[Cr$(en)_2Br_2]^+$ and trans-$[Cr(tn)_2Br_2]+^$ Ions (trans-[Cr$(en)_2Br_2]^+$ 및 trans-$[Cr(tn)_2Br_2]+^$ 착이온의 수화반응에 미치는 압력의 영향)

  • Jong Jae Chung;Park Kyung Suk
    • Journal of the Korean Chemical Society
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    • v.30 no.4
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    • pp.341-344
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    • 1986
  • The rate for the aquation of trans-[Cr$(en)_2Br_2]^+$ and trans-$[Cr(tn)_2Br_2]+^$ ions in the aqueous solution has been measured by the conductometric method at various pressures and temperatures. The rate constants are increased with increasing temperature and decreased with increasing pressure. Activation volumes are all positive values and lie in the limited range +1.6 ∼ +2.3Oc$m^3$/mole for trans-[Cr$(en)_2Br_2]^+$ and +1.30 ∼ +1.92c$m^3$/mole for trans-$[Cr(tn)_2Br_2]+^$. Activation entropies have small negative values while activation compressibilities have small positive values. From the above results, we may deduce that the mechanism for the aquation of these complexes is the $I_d$ mechanism.

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Influence of a Variety of Second Carbon Substrates on the Bacterial Consortium Differentially Degrading Cis- and Trans-1,3-Dichloropropene (1,3-D) (상업용 훈증제인 Cis-와 Trans-1,3-Dichloropropene(1,3-D)을 차별적으로 분해하는 Bacterial Consortium에 영향을 주는 다양한 이차 탄소원들의 효과)

  • Chung, Keun-Yook
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.7
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    • pp.1243-1252
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    • 2000
  • The differential enhanced degradation of cis- and trans-1,3-D was observed in the previous two studies performed by several researchers. This study was initiated to investigate the involvement of microorganisms in the differential enhanced degradation of the chemicals. As expected, microorganisms were responsible for the enhanced degradation. A mixed bacterial culture capable of degrading 1,3-D was isolated from an enhanced soil sample collected from a site treated with 1,3-D. Similar to the enhanced soil, the mixed culture degraded trans-1,3-D faster than cis-1,3-D. This mixed culture could not utilize cis- and trans-1,3-D as a sole source of carbon for growth. Rather, a variety of second substrates were evaluated to stimulate the differential enhanced degradation of the two isomers. As a result, the mixed culture degraded cis- and trans-1,3-D only in the presence of a suitable second substrate. Therefore, it appeared that the degradation of cis- and trans-1,3-D was a cometabolic process. Second substrates that had the capacity to stimulate the degradation included soil leachate, tryptone, tryptophan, and alanine. Other substrates tested. including soil extract. glucose, yeast extract and indole, failed to stimulate the degradation of the two isomers. The mixed culture was composed of four morphologically distinctive colonies on L-agar plates.

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The Production of Methyl Trans-cinnamate in the Submerged Cultures of Tricholoma matsutake Mycelia

  • Park, Youngki;Lee, Wi Young;Ahn, Jin Kwon
    • Journal of the Korean Wood Science and Technology
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    • v.35 no.5
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    • pp.109-117
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    • 2007
  • Methyl trans-cinnamate is a significant flavor compound of Tricholoma matsutake. Attempts were made to produce this compound by culturing the mycelium using submerged culture. No methyl trans-cinnamate could be detected when the mycelium was cultured in the basal liquid medium. However, the addition of Pinus desiflora extracts to the medium, methyl trans-cinnamate was largely produced. To find out compounds or fractions inducing methyl trans-cinnamate, dichloromethane fraction obtained from the wood extracts of P. densiflora was subjected to column chromatography. Three sub-fractions were obtained from the $CH_2CI_2$ fraction. Submerged cultured mycelium treated with sub-fraction 1 has the highest content of methyl trans-cinnamate. Maximum methyl trans-cinnamate $(470.2{\mu}g/g)$ was obtained when the first sub-fraction of dichloromethane fraction of the P. densiflora wood extracts was added to the medium. This indicates that wood extracts of P. densiflora contains inducer of the methyl trans-cinnamate production in the T. matsutake submerged culture.

A Comparative Study of the Anti-Platelet Effects of cis- and trans-Resveratrol

  • Kim, Hwa;Oh, Seok-Jeong;Liu, Yingqiu;Lee, Moo-Yeol
    • Biomolecules & Therapeutics
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    • v.19 no.2
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    • pp.201-205
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    • 2011
  • Although various biological activities of resveratrol have been extensively studied, most reports have focused on trans-resveratrol and little attention has been paid to the cis-isomer. In this study, the effect of cis-resveratrol on platelet activity was examined and compared with that of the trans-isomer. Treatment with cis-resveratrol resulted in inhibition of platelet aggregation induced by thrombin, collagen or ADP, which are representative aggregation-inducing agents, and the trans-isomer elicited the same effects. These effects were concentration-dependent in the range of 1-100 ${\mu}M$. However, the potency of the cis-isomer was much lower than that of the trans-isomer; the $IC_{50}$ values for the cis-isomer versus the trans-isomer were $31{\pm}12$ vs $151{\pm}3$, $161{\pm}3$ vs $91{\pm}4$, and $601{\pm}15$ vs $251{\pm}6\;{\mu}M$ for thrombin-, collagen- and ADP-induced aggregation, respectively. These results indicate that cis-resveratrol has a less potent anti-platelet activity, compared with the trans-isomer, and raise the possibility that the biological activities of the cis-isomer may be different from those of the trans-isomer. It will be necessary to evaluate the activity of cis-resveratrol independently of the trans-isomer.

Effects of Substrate RNA Structure on the Trans-splicing Reaction by Group I Intron of Tetrahymena thermophila (Tetrahymena thermophila의 group I intron에 의한 trans-splicing 반응에 미치는 표적 RNA 구조의 영향분석)

  • 이성욱
    • Korean Journal of Microbiology
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    • v.35 no.3
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    • pp.211-217
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    • 1999
  • Effects of subsh-ate RNA configuration on the tians-splicing reactcon by group I intron ribozyme of Tetralzynzena thern\ulcornerophila were analyzed with substrate RNAs which have been generated to have very stable structures with stem-loop. RNAinapping strategy was perfo~med in vivo as well as in virro to search the mosl accessible siles to the ~irms-splicing ribozymes in the substrate RNAs. Sequences present in the loop of the target RNAs have shown to be well recognized by and reacted with group I inlron ribozymes while sequences present in the stein do not. Thesc results were confirmed with the experiments of trans-cleavage and rmnssplicing reactmn with ihe specific ribozyines recognizing those sequences. Moreover, sequence analysis of the trans-splicing products have shown that irons-splicing reaction can proceed with high fidelity. In conclusion, the secondary structure of substrate RNAs is one of the most important factors to detemine the ribozyme activity.

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A Study on the concept of 'Trans Architecture' in Marcos Novak (마르코스 노박(Marcos Novak)의 트렌스 건축(Trans Architecture) 개념에 관한 연구)

  • Lee Kyu-Hong;Kim Kai-Chun
    • Korean Institute of Interior Design Journal
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    • v.15 no.4 s.57
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    • pp.46-54
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    • 2006
  • The present study examined Marcos Novak, a digital architect who has researched digital architecture and produced related works since the early 1990s. Starting from digital ideas originating from science and mathematics, he pursued 'trans architecture' based on the concept of 'architecture beyond the boundary of architecture' and 'architecture as invisible foundation.' His concept of 'trans architecture' is considered an important viewpoint in expressing the architecture of a diversified and hybridized age like today. The objective of this study was to understand the concepts of Allobio and Eversion, which are important digital terms forming the background of Novak's trans architecture, and to analyze architecture philosophy and architecture design concepts observed in his works through Novak's digital terminology centering on the concept of trans architecture pursued by him. Through this, we purposed to analyze the concept of architectural space, methods of form creation and the characteristics of trans architecture space, which were unique to Novak, the leader of digital architecture, and ultimately to provide basic materials on Novak. Novak's trans architecture represents digital architecture in the contemporary diversified and hybridized age, and his works involve various different digital elements and ideas, scientific paradigms, mathematic algorithms, 4 dimensional geometry, etc. In this sense, he is regarded as a prominent leading advocate of digital architecture.

Effects of Concentrate to Roughage Ratio on the Formation of cis-9, trans-11 CLA and trans-11-Octadecenoic Acid in Rumen Fluid and Plasma of Sheep When Fed High Oleic or High Linoleic Acid Oils

  • Wang, J.H.;Choi, S.H.;Song, M.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.11
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    • pp.1604-1609
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    • 2003
  • A metabolism trial with four ruminally fistulated sheep was conducted in a $4{\times}4$ Latin square design to examine the effect of concentrate to roughage ratio (70:30 vs. 85:15) and oil source (soybean oil vs. rapeseed oil) on the ruminal fermentation pattern and $C_{18}$-fatty acids composition including trans11-$C_{18:1}$ (trans11-ODA) and cis9, trans11-18:2 (cis9, trans11-CLA) in the rumen fluid and plasma. Oil was added to the concentrate at 5% level of the total diet (DM basis) and chopped rye grass hay was fed as roughage. An increased level of concentrate (85%) within supplemented oil slightly lowered pH but increased ammonia concentration. Supplementation of rapeseed oil relatively increased pH and ammonia concentration. Higher concentrate level resulted in increased tendencies of total VFA concentration while oil source did not affect the total VFA concentration and VFA proportion. Whole tract digestibilities of DM, CP, EE, NDF and OM in diets slightly increased at higher concentrate level. Proportions of oleic acid ($C_{18:1}$) and linoleic acid ($C_{18:2}$) in the rumen fluid were influenced by the fatty acid composition of oil source but oil source did not affect the in vitro formations of trans11-ODA and cis9, trans11-CLA. Slightly increased trans11-ODA and cis9, trans11-CLA proportions, however, were observed from the sheep fed high roughage diet supplemented with both soybean oil and rapeseed oil. The $C_{18:1}$ and $C_{18:2}$ composition in supplemented oils responded to those in plasma of sheep. Effects of concentrate to roughage ratio and oil source on trans11-ODA and cis9, trans11-CLA proportions in plasma were found to be small. Proportion of cis9, trans11-CLA in plasma tended to be increased from the sheep fed high roughage diet and collection time at 9h post feeding.

A Study on the Formation of Trans Fatty Acids with Heating and Storage of Fats and Oils (I) - The Change of Physicochemical Characteristics and Total Trans Fatty Acids Content - (유지의 가열 및 저장에 따른 Trans 지방산 생성에 관한 연구(I) -일부 이화학적 특성 및 Trans 지방산 함량변화를 중심으로-)

  • Kim, Duck-Sook;Koo, Bon-Soon;Ahn, Myung-Soo
    • Korean journal of food and cookery science
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    • v.6 no.2
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    • pp.37-50
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    • 1990
  • The cause and the degree of the cis to trans isomerization were investigated about soybean oil (SBO), corngerm oil (CGO), cottonseed oil (CSO), margarine (MG) and shortening (ST). All samples treated with various conditions were analyzed to determine physicochemical characteristics (AV, POV, IV, RI), fatty acid composition, total trans fatty acid content and change of trans fatty acid composition by GLC, IR and HPLC. The results were obtained as follows; 1. Physicochemical constants were changed with a gentle slope according to incubating period at 40${\pm}$2$^{\circ}C$ and physicochemical constants of margarine and shortening were changed, significiantly. 2. The saturation degree in the unsaturated fatty acid composition determined by GLC gradually were increased during incubation and heating periodically. For palmitic-and stearic acid content at the samples stored in the incubator, the saturation degrees were gradually increased. But for the case of heat treatment, they were increased more rapidly than other fatty acids. 3. Total trans fatty acid contents in each samples were determined by GLC, IR and HPLC, the amount of trans fatty acids were measured with discrepancy. It was caused by deviation of analytical instruments, methods and the kinds of samples. Trans fatty acids were measured more definitly in IR more than GLC and HPLC. On the other hand, total trans fatty acid contents in average levels for SBO, CGO, CSO, MG and ST stored for 35 days and heated for 24 hours were 1.3%, 1.1%, 0.9%, 22.6% and 13.8%, and 3.6%, 3.0%, 2.8%, 41.2% and 20.8%, respectively.

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