• Bulletin of the Korean Chemical Society
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• v.17 no.11
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• pp.1040-1044
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• 1996

The catalytic dehydrocoupling of bis(1-sila-3-butyl)benzene, 1 by Cp2ZrCl2/Red-Al and Cp2ZrCl2/n-BuLi combination catalysts yielded a mixture of oily and solid polymers. While the catalytic dehydrocoupling of 2-phenyl-l,3-disilapropane, 2 by Cp2ZrCl2/n-BuLi combination catalyst produced a mixture of oily and solid polymers, the catalytic redistribution/dehydrocoupling of 2 by Cp2ZrCl2/Red-Al combination catalyst gave oily polymer. The dehydrocoupling of 1 and 2, unless the prior silane redistribution occurs, seems to initially produce a low-molecular-weight polymer, which then undergoes an extensive cross-linking reaction of backbone Si-H bonds, leading to an insoluble polymer.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.2
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• pp.97-114
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• 1977

The fresh water prawn, Macrobrachium rosenbergi(de Man) is a very common species in Indopacific region, which inhaits both fresh and brackish water in low land area, most of rivers and especially aboundant in the lower reaches which are influenced by sea water. It is one of the largest and commercial species of genus Macrobrachium, which is commonly larger than $18\~21cm$ in body length, from the basis of eye-stalked to the distal of telson. As a part of the researches in order to investigate the possibilities on transplantation and propagation of this species, this work dealt with the problems on the effects of chlorinities upon zoeal larvae and post-larvae 1). metamorphosis rate and optimum chlorinity for metamorphosis to post-larve, 2). tolerance and comparative survival rate on various chlorinties, from fresh water to sea water $(19.38\%_{\circ}\;Cl)$, which reared for six days upon each stage of zoeal larvae, 3). accomodation rate on chlonities which reared for twelve days after transmigration into variant chlorinities of the range from $3.68\%_{\circ}$ Cl to $1.53\%_{\circ}$ Cl in the way of rearing of the range from $3.82\%_{\circ}$ Cl to $11.05\%_{\circ}$ upon each stage of zoea, 4). tolerance on both of fresh and sea water upon zoeal larva and post-larva under the condition of $28^{\circ}C{\pm}1$ in temperature and feeding on Artenia salina nauplii, 5). relationship between various chlorinities and grwth of post-larvae under the condition of $28^{\circ}C$ in tmperature and feeding on meat of clam. Thus these investigations were performed in order to grope for a comfortable method on seedmass production. Up to the present, the study on the effects of chlorinity upon earlier zoeal larvae and post-larvae of Macrobrachium species has been scarcely performed by workers with the exception of Lewis(1961) and Ling (1962,, 1967), even so their works were not so detailed. On the other hand, larvae of several species of this genus were reared at the water which mixed sea water so as to carry out complete metamorphosis to post-larva by workers in order to investigate on earlier 1 arval and earlier post-larval development, such as Macrobrachium lamerrei (Rajyalakshmi, 1961), M. rosenbergi and M. nipponense (Uno and Kwoa, 1969; Kwon and Uno, 1969), M. acanthurs (Choudhury, 1970; Dobkin, 1971), M. carcinus(Choudhury, 1970), M. formosense(Shokita, 1970), M. olfersii (Duggei et al., 1975), M. novaehallandiae (Greenwood et al., 1976), M. japonicum (Kwon, 1974) and M. lar (Shokita, personal communication), and there fore it is regarded that chlorinity is, generally, one of absolute factors to rear zoeal larvae of brackish species of Macrobrachium genus. Synthetic results on this work is summarized as the follwings: 1) Zoeal larvae required different chlorinities to grow according to each stage, and generally, it is regarded that optimum range of living and growing is from $7.63\%_{\circ}Cl\to\;7.63\%_{\circ}Cl$, and while differences of metamorphsis rate, from first zoea to post-larva, is rarely found in this range, and however it occurs apparently in both of situation at $7.63\%_{\circ}Cl$ below and $16.63\%_{\circ}Cl$ above and moreover, metamorphosis rate is delayed somewhat in case of lower chlorinity as compared with high chlorinity in these situations. 2) Accomodation in each chlorinity on the range, from fresh water to sea water, is different according to larval stages and while the best of it is, generally, on the range from $14.24\%_{\circ}Cl$ to $8.28\%_{\circ}Cl$ and favorite chlorinity of zoea have a tendency to remove from high chlorinity to lower chlorinity in order to advance larval age throughout all zoeal stages, setting a conversional stage for eighta zoea stage. 3) Optimum chlorinity of living and growth upon postlarvae is on the range of $4.25\%_{\circ}Cl$ below, and in proportion as approach to fresh water, growth rate is increased. 4) Post-large are able to live better in fresh water in comparison with zoeal larvae, which are only able to live within fifteen hours, and by contraries, post-larvae are merely able to live for one day as compared with ?미 larvar, which are able to live for six days more in sea water $19.38\%_{\circ}Cl\;above$. 5) Also, in case of transmigration into higher and lower chlorinities in the way of rearing in the initial chlorinities $ 3.82\%_{\circ}Cl,\;7.14%_{\circ}Cl\;and\;11.05%_{\circ}Cl$, accoodation rate is a follow: accomodation capacity in ease of removing into higher chlorinities from lower chlorinities is increased in proportion as earlier stages, setting a conversional stage for eighth zoea stage, and by contraries, in case of advanced stages from eighth zoea it is incraesed in proportion as approach to post-larva stage in the case of transmigration into lower chlorinity from higher chlorinity. On the other hand, it is interesting that in case of reciprocal transmigration between two different chlorinitiess, each survival rate is different, and in this case, also, its accomodation in each zoea stage has a tendency to vary according to larval stages as described above, setting a conversional stage for eighth zoea stage. 6) It is likely that expension of radish pigments on body surface is directly proportional to chlorinity during the period of zoea rearing, and therefore it seems like all body surfacts of zoea larvae be radish coloured in case of higher chlorinity. 7) By the differences that each zoeal larvae, postlarvae, juvaniles and adult prawn are required different chlorinity for inhabiting in each, it is regarded that this species migrats from up steam to near the estuary of the river which the prawns inhabits commonly in natural field for spawning and growth migration. 8) It had better maintainning chlorinities according to zoeal stage for a comfortable method on seed-mass production that earlier larva stages than eighth zoea are maintained on the range from $8\%_{\circ}Cl\;to\;12\%_{\circ}Cl$ to rear, and later larva stages than eighth zoea, by contraries, are gradually regula ted-to love chlorininity of the range from $7\%_{\circ}Cl\;to\;4\%_{\circ}Cl$ according to advance for post-larva stage.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.143-150
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• 2009

Deicing salt is used to melt snow and ice on the road for traffic safety during the winter season, which accumulates in the roadside vegetation and induces visible injuries. The damage may accelerate particularly when it coincides with early spring leaf out. In order to better understand the response mechanisms, C. kousa (3-year-old) was irrigated twice prior to leaf bud in a rhizosphere with solutions of 0.5, 1.0, and 3.0% calcium chloride ($CaCl_2$) concentration, that were made by using an industrial $CaCl_2$ reagent practical deicing material in Seoul. Physiological traits of the mature leaves were progressively reduced by $CaCl_2$ treatment, resulting in reductions of total chlorophyll contents, chlorophyll a:b, photosynthetic rate, quantum yield, stomatal conductance, $F_V/F_M$, and NPQ. On the contrary, light compensation point and dark respiration were increased at high $CaCl_2$ concentration. A decrease in intercellular $CO_2$ concentration by stomatal closure first resulted in a reduced photosynthetic rate and then was accompanied by low substance metabolic rates and photochemical damage. Based on the reduction of physiological activities at all treatments ($CaCl_2$ 0.5%, 1.0%, and 3.0%), C. kousa was determined as one of the sensitive species to $CaCl_2$.

• Bulletin of the Korean Chemical Society
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• v.16 no.9
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• pp.835-839
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• 1995

Mer,trans-Re(≡NC6H5)(PPh3)2Cl3, Ⅰ, reacted with trimethylphosphine to give a mixture of two stereoisomers, mer,trans-Re(≡NC6H5)(PMe3)2Cl3,Ⅱ, and fac,cis-Re(≡NC6H5)(PMe3)2Cl3, Ⅲ. These compounds could also be prepared from the reaction of Re(≡NC6H5)(PMe3)(PPh3)Cl3 with trimethylphosphine. In both reactions the mer,trans-isomer is a major product. The products have been characterized by NMR, elemental analysis, and X-ray crystallography. Crystal data for Ⅱ: monoclinic space group P21, a=10.053(1) Å, b=10.844(1) Å, c=10.058(2) Å, β=113.45(2)°, Z=2, R(wR2)=0.0348 (0.0894). Crystal data for Ⅲ: monoclinic space group P21/n, a=7.183(2) Å, b=16.983(4) Å, c=15.543(4) Å, β=90.38(2)°, Z=4, R(wR2)=0.0603 (0.1484).

• The Korean Journal of Food And Nutrition
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• v.15 no.2
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• pp.144-150
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• 2002

Sweet persimmon were tested in order to identify their use as secondary material which is excellent in function and taste as food. Samples were soaked for 1 and 5 min with NaCl concentration(0, 1 and 3%) at a certain heating temperature(25, 75 and 95$\^{C}$), and then tannin, vitamin C, flavonol, color intensity, sensory test and textural properties were analysed. The results of the analyses were as follows. Tannins were decreased as heating temperature, NaCl concentration and soaking time were increased, especially, that the control was 420 mg% but decreased 228 and 198 mg% at 95$\^{C}$(1 and 3% NaCl concentration) for 5 min. soaked in each. Vitamin C content also decreased more in higher temperature and NaCl concentration than control(122.4 mg%). Color intensity showed higher value in 1. and b than in heating temperature, NaCl concentration and soaked time longer remarkably, but a value decreased. The peel of sweet persimmons was analyzed myricetin(2.0 $\mu$g/g), quercetin(34.5 $\mu$g/g) and kaemperol(1.1$\mu$g/g), but in pre-treatment sample(95$\^{C}$, 1% NaCl concentration and 5 min. soaked) was showed higher myricetin(9.5 $\mu$g/g) and quercetin(5.5 $\mu$g/g). Textural properties were good in pre-treatment sample(95$\^{C}$, 1% NaCl concentration and 5 min. soaked) such as brittleness, cohesiveness, gumminess and chewiness. In sensory analysis, the pre-treatment samples(95$\^{C}$, 1% NaCl concentration and 5 min. soaked and 95$\^{C}$, 3% NaCl concentration and 1 min. soaked) were showed higher point than others.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.3
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• pp.259-268
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• 2012

This study suggests quantitative guidelines for inside clothing temperatures to improve the heat tolerance of 20's females in summer. First, the inside clothing temperatures ($T_{cl}$) of each subject was measured in daily use. The subjects were asked to record subjective thermal sensations, clothing items worn, clothing weight, and activities during an experiment designed to determine the comfort zone of $T_{cl}$. In a thermally neutral state, the comfort zone of $T_{cl}$ was decided on a mean value $T_{cl}{\pm}1{\sigma}$. Second, the subjects were asked to wear clothing that would enable them to feel 'slightly warm but still comfortable'. The rest of the processes were the same as previous steps that were designed to understand the way and degree of clothing control. The comfort zone of $T_{cl}$ was decided in the same manner as the previous step. The two comfort zones were combined and named the combined comfort zone of the definitive comfort zone. The results were as follows: 1. Thermally comfortable $T_{cl}$, Hcl were $34.0{\pm}1.1^{\circ}C$, $40{\pm}9%%RH$ and the thermally comfortable ambient climate was $25.0{\pm}1.6^{\circ}C$, $53{\pm}7%$RH. 2. When subjects were asked to wear 'slightly warm but still comfortable', there were difference in thermally comfortable $T_{cl}$, clothing weight and clothing layer by subject. 3. In this study, the optimal $T_{cl}$ was decided on the mid-point of the definitive comfort zone of $T_{cl}$.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3600-3604
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• 2010

Rhodium(III)-$Cp^*$ complexes containing labile ligands, $[Cp^*RhCl_2]_2$, [$Cp^*Rh({\eta}^2-NO_3)$(OTf)], and $[Cp^*Rh(OH_2)_3](OTf)_2$, reacted with potential linking ligands [$L^1$ = (2-thiophene)-CH=N-N=CH-(2-thiophene); $L^2$ = (2-furan)-CH=N-N=CH-(2-furan)] to give two molecular compounds, [$Cp^*Rh(L^1)Cl_2$] (1) and [$Cp^*Rh({\eta}^2-NO_3)(L^1)$]$(OTf){\cdot}CH_2Cl_2$ ($2{\cdot}CH_2Cl_2$), and one 1-dimensioanl coordination polymer, $\{[Rh(L^2)]{\cdot}(OTf)}_{\infty}$ (3). Whereas one imine nitrogen atom within the ligand is coordinated to the Rh metal in compounds 1 and 2, both nitrogen atoms are bound to two neighboring Rh metals in compound 3 to lead to a 1-D chain polymer.

• Bulletin of the Korean Chemical Society
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• v.28 no.3
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• pp.421-426
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• 2007

A linking ligand containing sulfur donor atoms in the terminal thiophene rings, 1,2-bis(thiophen-2-ylmethylene) hydrazine (L), was prepared by Schiff-base condensation. Ligand L reacted with [PdCl2(NCPh)2] to produce a molecular Pd compound [PdL2Cl2] (1). On the other hand, it reacted with AgNO3 and AgClO4 to produce a 2-D network [AgL0.5(NO3)] (2) and a 1-D polymer [AgL]ClO4 (3), respectively, whose structures are based on secondary intermolecular forces such as H-bonding, van der Waals interaction, and π-π stacking. Polymer 2 exhibited photoluminescence at room temperature in the solid state.

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.2009-2014
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• 2007

The aminolysis of diphenyl thiophosphinic chloride (2) with substituted anilines in acetonitrile at 55.0 oC is investigated kinetically. Kinetic results yield large Hammett ρX (ρnuc = ?3.97) and Bronsted βX (βnuc = 1.40) values. A concerted mechanism involving a partial frontside nucleophilic attack through a hydrogen-bonded, four-center type transition state is proposed on the basis of the primary normal kinetic isotope effects (kH/kD = 1.0-1.1) with deuterated aniline (XC6H4ND2) nucleophiles. The natural bond order charges on P and the degrees of distortion of 42 compounds: chlorophosphates [(R1O)(R2O)P(=O)Cl], chlorothiophosphates [(R1O)(R2O)P(=S)Cl], phosphonochloridates [(R1O)R2P(=O)Cl], phosphonochlorothioates [(R1O)R2P(=S)Cl], chlorophosphinates [R1R2P(=O)Cl], and chlorothiophosphinates [R1R2P(=S)Cl] are calculated at the B3LYP/ 6-311+G(d,p) level in the gas phase.

• Korean Journal of Crystallography
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• v.10 no.2
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• pp.119-124
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• 1999

X-선 회절법을 이용하여 3,6-bis(6'-methyl-2'pyridyl)pyridazine을 리간드로 한 Zn(Ⅱ) 착물인 [3,6-bis(6'-methyl-2'pyridyl)pyridazine]ZnCl2 (C16H16N4·ZnCl2)의 결정구조를 규명하였다. 이 결정의 결정계는 Monoclinic이며 공간군은 P21/a이다. 단위포 상수는 a=15.053(7) Å, b=14.594(7) Å, c=7.628(3) Å이며, β=93.92(4)°, V=1671.9(13) Å3, T=293(2)K, Z=4, Dc=1.594 Mgm-3이다. 회절반점들의 세기는 Enraf-Nonius CAD-4 diffractometer로 얻었으며 Mo Kα선(λ=0.71073 Å)을 사용하였다. 분자구조는 직접법으로 풀었으며, Fo>4σ (Fo)인 1750개의 독립 회절 데이터에 대하여 최소승자법으로 정밀화하여 최종 신뢰도 값 R=8.31%을 얻었다.