• Macromolecular Research
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• v.8 no.5
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• pp.238-242
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• 2000

The new trisiloxane-bridged heterometallic dinuclear metallocenes, hexamethyltrisiloxanediyl(cyclopentadienyltitanium trichloride) (cyclopentadienylindenyl zirconium dichloride) , $C_3ITi-Cp(CH_3)_2Si-O-Si(CH_3)_2-O-Si(CH_3)_2-Cp-ZrIndCI_2$ (1) and hexamethyltrisiloxanediyl (cyclopentadienylindenylhafnium dichloride) (cyclopentadienylindenyl zirconium dichloride), $C_2IndHf-Cp(CH_3)_2Si-O-Si(CH_3)_2-Cp-ZrIndCl_2$ 2) connecting two dissimilar metallocenes were synthesized and used for ethylene polymerization in the presence of modified methylaluminoxane (MMAO) cocatalyst. The catalytic activity of heterometallic dinuclear metallocenes, 1 and 2 was lower than that of corresponding mononuclear metal-locene as well as two physically mixed catalysts, $CpTiCl_2/Cp_2ZrCl_2 and Cp_2HfCl_2/Cp_2ZrCl_2$. On the tither hand, MWD of PE obtained with 1 and 2 was remarkably broader ($M_w/M_n$) became up to 9.4) than those of PEs prepared with the corresponding mononuclear metallocenes and mixed catalysts. With analysis by GPC and CFC, it was found that PE produced by the heterometallic dinuclear metallocenes exhibited the definite bimodal GPC curves that should cause the broadening of MWD.

• Journal of the Korean Chemical Society
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• v.38 no.1
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• pp.55-60
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• 1994

Molecular orbital calculations at the extended Huckel level have been carried out for $Cp_2TiSiHPh(1),\;[Cp_2Ti]_2[{\mu}-HSi(HPh)][{\mu}-H] (2),\;and\;[Cp_2TiSiH_2Ph]_2$ (3) complexes which are important intermediates in organosilane polymerization. Stable geometry of complex 1 is not $C_{2V}$, but Cs symmetry and the rotational energy barrier of $SiH_2$ unit is computed to be 14 kcal/mol. The orbital interaction diagrams are studied to characterize the chemical bonding for the electron deficient systems, 2 and 3. It is possible for Si-H to be coordinated to the Ti metal using $\sigma$ bonding.

• Fashion & Textile Research Journal
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• v.21 no.4
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• pp.459-467
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• 2019

Compression wear provides clothing pressure and affects how blood flows. Facilitating a blood flow is one of the most important functions of compression wear. The wearer's sensibility should be considered when designing compression wear. This study instructed participants to put on 5 types of sport compression wear with different pressure levels (CP-1 to CP-5), measured clothing pressure, blood flow level, blood flow rate, and surface temperature, and examined the pressure level that influenced blood flow through a subjective sensibility assessment. An experiment measured the clothing pressure of compression wear available in the market and found that the pressure ranged 0.6-1.1 kPa for the ankle, 0.7-2.3 kPa for the calf, and 0.9-1.9 kPa for the thigh. Meanwhile, blood flow levels and rates significantly increased when participants wore CP-1, which had the highest clothing pressure level, and CP-2 and CP-4 with middle-level pressure. After exercise, CP-2's surface temperature was the highest and revealed that wearing CP-2 facilitated blood flow. CP-2 was evaluated as most positive in the sensibility assessment and showed a clothing pressure of 0.67-1.82 kPa; its pressure for the calf did not surpass 2.0 kPa. Considering positive physical effect of compression wear on blood flow and subjective psychological effect on participants, CP-2 (0.67-1.82 kPa) would have the most suitable clothing pressure level among other types of the wear in this study.

• Journal of Integrative Natural Science
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• v.4 no.3
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• pp.177-181
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• 2011

The catalytic dehydrocoupling of bis(1-sila-3-butyl)benzene 1 and 2-phenyl-1,3-disilapropane 2 by $Cp_2ZrCl_2$/Red-Al and $Cp_2ZrCl_2$/n-BuLi was reported to compare their catalytic efficiency. The dehydrocoupling of monomeric silanes 1 with the $Cp_2ZrCl_2$/Red-Al and $Cp_2ZrCl_2$/n-BuLi combination catalysts produced two phases of polymers: one is a highly cross-linked insoluble solid, and the other is noncross-linked or slightly cross-linked soluble oil and could be a precursor for the solid polymer. The dehydrocoupling of 2 with the $Cp_2ZrCl_2$/n-BuLi combination catalyst similarly produced two phases of polymers. By contrast, the catalytic reaction of 2 with the $Cp_2ZrCl_2$/Red-Al combination catalyst produced a soluble polymer via redistribution/dehydrocoupling process.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.179-185
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• 2000

In this study, we examined the movement of chlorophenol as a precursor of the dioxin in the after-combustion to minimize the creation and emission of dioxin in a municipal waste incinerator. The CPs was injected to the electric incinerator in temperature $300{\sim}500^{\circ}C$, using $N_2$ gas to control the reaction time, The oxygen quantity supplied into the $CP_s's$ isomer combustion was added with the value of experience formula. When the space velocity in reactor was 60~80/sec, the removal efficiency of CP was obtained in the presence of Mo-V catalyst and non catalyst. The efficiency in non-catalyst was 74% to 80% mono-CP, di-CP 55~66%, tri-CP 50~58%, while mono-CP 90~99.9%, di-CP 96~97%, tri-CP 76~99% in a catalyst. Consequently, it was shown that these were 20~30% more efficienct than those.

• Bulletin of the Korean Chemical Society
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• v.14 no.6
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• pp.669-673
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• 1993

The CO substitution reactions of the complex, $Cp(S-2,4-Me_2C_5H_5)CrCo$ with $PR_3(PR_3=PMePh_2,\;P(OCH_3)_3,\;PMe_2Ph)$ were investigated spectrophotometrically at various temperatures. From the reaction rates, it was suggested that the CO substitution reaction took place by first-order (dissociative) pathway. Activation parameters in decaline were ${\Delta}H^{\neq}\;=\;22.0\;kcal{\cdot}mol^{-1}$, ${\Delta}S^{\neq}=\;-3.8cal{\cdot}mol^{-1}{\cdot}K^{-1}$. Unusually low value of ${\Delta}S{\neq}$ suggests an ${\eta}^5-S{\to}{\eta}^5-U$ conversion of the pentadienyl ligand. This suggestion was confirmed by the Extended-Huckel molecular orbital (EHMO) calculations, which revealed that the total energy of $Cp(S-2,4-Me_2C_5H_5$)CrCO is about 0.42 kcal/mol more lower than that of $Cp(U-2,4-Me_2C_5H_5)CrCO$ and the energy of $[Cp(U-2,4-Me_2C_5H_5)Cr{\cdots}CO]^{\neq} $ transition state is about 2.43 kcal/mol lower than that of $[Cp(S-2,4-Me_2C_5H_5)Cr{\cdots}CO]^{\neq}$ transition state.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.4
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• pp.723-731
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• 1992

Two similar experiments were designed to evaluate the interaction of dietary CP and ME levels on the production performance parameters at the age between 155 and 300 days in Starcross layers. In both experiments, the feed intake and mortality decreased but the egg weight, body weight gain and feed conversion efficiency increased as the dietary CP and ME levels increased. The CP intake was highest CP and lowest ME levels. With the increasing CP and decreasing ME levels, the ME intake decreased significantly (Experiments 1 & 2). The $CP{\times}ME$ interactions were significant only on mean egg weight and egg production in Experiment 2. In both the experiments, the CP levels were positively correlated with CP intake, egg weight, body weight gain and egg production and negative correlation with feed intake, mortality percentage and ME intake. The ME levels showed negative correlation with feed intake, protein intake, mortality percentages and positive correlation with all other parameters in both experiments. The highest values were noted for all the parameters (except mortality percentages) in Experiment 1 than that recorded in Experiment 2.

• The Journal of Korean Medicine
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• v.41 no.3
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• pp.55-65
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• 2020

Objectives: This study aimed to evaluate the toxicity of CP pharmacopunture using bacterial reverse mutation test. Methods: To determine the mutagenic potential of CP pharmacopunture, histidine requiring Salmonella typhimurium (TA98, TA100, TA1535, and TA1537) and tryptophan requiring Escherichia coli (WP2uvrA, pKM101) strains were used. The negative (normal saline solution) and positive (Sodium azide, 2-Nitrofluorene, 2-Aminoanthracene, 9-Aminoacridine, and 4-Nitroquinoline N-oxide) control groups were used. To determine the dose levels of the main study, a dose range-finding study was conducted. Results: As a results of the dose range-finding study, the growth inhibition by CP pharmacopunture was not evident at any dose levels in the absence and presence of metabolic activation. As a results of the main study, the mean number of revertant colonies was less than twice when compared to the negative control values at all dose levels of the CP pharmacopuncture in the presence and absence of metabolic activation, showing no dose-related increase. In the positive control group, the number of revertant colonies was markedly increased by more than twice when compared to the negative control group. Conclusion: According to the results of this study, CP pharmacopunture did not show any signs of mutagenic potential.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.6
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• pp.721-724
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• 2009

Astaxanthin is a valuable pigment source for many aquacultured species, including salmonoids, shrimp, sea bream, and ornamental species. Conjugated linoleic acid (CLA) and ascidian tunic extracts were mixed with the basal diet of rainbow trout to investigate their pigmentation effects. Synthetic Carophyll Pink and natural carotenoids that came from the tunic extracts were incorporated into muscle and skin tissues. The main carotenoids found in muscle after 8 weeks were canthaxanthin in CP12 (13.4%), and CP52 (17.2%), and astaxanthin in CP12 (58.5%), and CP52 (59.2%) in the Carophyll Pink group, while those in skin were canthaxanthin in CP14 (34.5%), and CP54 (29.2%), and astaxanthin in CP14 (32.0%), and CP54 (36.5%) in the ascidian tunic extract group. The total carotenoid content in skin (53.0-69.3 mg/kg) was greater than that in muscle (9.5-13.8 mg/kg).

• Journal of Powder Materials
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• v.1 no.1
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• pp.42-51
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• 1994

6061Al-SiCP metal matrix composite materials(MMCs) were fabricated by injecting SiCP particles directly into the atomized spray. The main attraction of this technique is the rapid fabrication of semi-finished, composite products in a combined atomization, particulate injection(10 $\mu\textrm{m}$, 40 $\mu\textrm{m}$, SiCP) and deposition operation. Conclusions obtained are as follows; The microstructure of the unreinforced spray formed 6061Al alloy consisted of relatively fine(50 $\mu\textrm{m}$) equiaxed grains. By comparision, the microstructure of the I/M materials was segregated and consisted of relatively coarse(150 $\mu\textrm{m}$) grains. The probability of clustering of SiCP particles in co-sprayed metal matrix composites increased it ceramic particle size(SiCP) was reduced and the volume fraction was held constant. Analysis of overspray powders collected from the spray atomization and deposition experiments indicated that morphology of powders were nearly spherical and degree of powders sphercity was deviated due to composite with SiCp particles. Interfacial bonding between matrix and ceramics was improved by heat treatment and addition of alloying elements(Mg). Maximum hardness values [Hv: 165 kg/mm2 for Al-10 $\mu\textrm{m}$ SiCp Hv--159 kg/mm2 for Al-40 $\mu\textrm{m}$SiCp] were obtained through the solution heat treatment at $530^{\circ}C$ for 2 hrs and aging at $178^{\circ}C$, and there by the resistance were improved.