• Bulletin of the Korean Chemical Society
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• v.26 no.2
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• pp.233-237
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• 2005

Cyclopentadiene compounds, 2-[CR'R(OMe)]-1,3-Me$_2C_5H_3$ (R, R' = 2,2'-biphenyl, 2) and 2-[CR'R(OSiMe$_3$)]-1,3-Me$_2C_5H_3$ (R, R' = 2,2'-biphenyl, 3; R = ph, R' = ph, 4; R = 2-naphthyl, R' = H, 5) are readily synthesized from 2-bromo-3-methoxy-1,3-dimethylcyclopentene (1). Reaction of the cyclopentadienes with Ti(NMe$_2$)$_4$ in toluene results in clean formation of the cyclopentadienyl tris(dimethylamido)titanium complexes, which are transformed to the trichloride complexes, 2-[CR'R(OMe)]-1,3-Me$_2C_5H_2$}TiCl$_3$ (R, R' = 2,2'-biphenyl, 6) and {2-[CR'R(OSiMe$_3$)]-1,3-Me$_2C_5H_2$}TiCl$_3$ (R, R' = 2,2'-biphenyl, 7; R = ph, R' = ph, 8; R = 2-naphthyl, R' = H, 9). Attempts to form C1-bridged Cp/oxido complexes by elimination of MeCl or Me$_3$SiCl were not successful. X-ray structures of 6, 7 and an intermediate complex {2-[Ph$_2$C(OSiMe$_3$)]-1,3-Me$_2C_5H_2$}TiCl$_2$(NMe$_2$) (10) were determined.

• The Korean Journal of Ecology
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• v.15 no.4
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• pp.355-363
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• 1992

Nitrate reductase activity(NRA) and induced NRA were compared in 4 species of moss ctenidium molluscum, homalothecium, tortella tortusa and neckera crispa collected from limestone in england. the NRA and dry weight of the c. molluscum were also measured after spraying with acidic deposition adjusted to ph 5.6, 4.6, 3.6 and 2.8 with one of two molar ratios of nitric to sulfuric acid, i.e. 1:0(N alone) and 1:2(1N+2S) for 20 days. All 4 species showed high NR leavels in the upper part of cut shoots and occurred maximum inducation of NRA within 6h. c. molluscum had the highest NRA levels among 4 species. after daily spraying of acidic deposition, NRA of c. molluscum was increased much more largely at ph 6 and ph 3.6 derived from N alone than from 1N+2S. However that was decreased at ph 2.8 derived both from N alone and 1N+2S . Decline of dry weight had occurred at ph 3.6 and 2.8 derived both from N alone and 1N+2S. Whereas substantial fertilization effect was observed at ph 4.6 derived from N alone. the data suggest that c. molluscum are able to utilize nitrate more effectivery than any other species, and NRA induction are more sensitive than growth response to nitrogen content of acidicdeposition in a short- term. however toxic effects was detected at high $NO_3$ supply and low phacidic deposition.

• Bulletin of the Korean Chemical Society
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• v.20 no.4
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• pp.427-430
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• 1999

The Grignard coupling reaction of bis(chloromethyl)diorganosilanes [(ClCH2)2SiR1R2: R1 = R2 = Me, la; R1 = Me, R2 = Ph, lb; R1 = R2 = Ph, lc] with diorganodichlorosilanes [(Cl2SiR3R4: R3 = R4 = Me, 2a; R3 = Me, R4 = Ph, 2b; R3 = R4 = Ph, 2c] at THE reflux temperature gave the intermolecular C-Si coupling product of 1,1,3,3-tetraorgano-1,3-disilacyclobutanes 3a-f in poor to moderate yields ranging from 7% to 50% along with polydiorganosilapropanes. The cyclization reaction of la-c with methyl-substituted dichlorosilanes 2a, b gave 1,3-disilacyclobutanes 3a-c, e, d in moderate yields (42-50%), while the same reaction with dichlorodiphenylsilane (2c) to 1,3-disilacyclobutanes 3d, f resulted in low yield (7-18%) probably due to the steric hindrance of two-phenyl groups on the silicon of 2c.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.6
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• pp.23-29
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• 2013

In this paper, pure $I_{ph}$ and hybrid carbon nanotube reinforced $I_{ph}$ were sintered using the SPS(spark plasma sintering) method for high densification. A nanosecond laser (${\lambda}=1063nm$, ${\tau}P=10ns$) and a femtosecond laser (${\lambda}=1027nm$, ${\tau}P=380fs$) were installed on an optical system for the micromachining test. The ablation characteristics of the pure $I_{ph}$ and CNT/$I_{ph}$ composites, such as thermal effect and ablation depth, were investigated using FE-SEM and a confocal microscope device. Laser machining results for the two mating materials showed improved performances: CNT/$I_{ph}$ composites showed good surface morphology of hole drilling without a melting zone due to the composites' high thermal properties; also, the ablated depth of CNT/$I_{ph}$ was higher than that of pure $I_{ph}$.

• Journal of the Korean Chemical Society
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• v.36 no.2
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• pp.248-254
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• 1992

Bis(phosphine)ruthenium derivatives $({\eta}^5-C_5Me_5)RuCl(PR_3)_2(PR_3=PMe_3,\; PMe_2Ph,\;PEt_3,\;PMePh_2$, 1/2DPPE, 1/2DPPB) (2a${\sim}$2f) have been synthesized by the reaction of $[({\eta}^5-C_5Me_5)RuCl_2]_2$ (1) with excessive phosphine in ethanol. The reaction of complexes $({\eta}^5-C_5Me_5)Ru(PR_3)_2Cl\;with\;NaBH_4$ in ethanol gave the corresponding hydride complexes $({\eta}^5-C_5Me_5)Ru(PR_3)_2H (PR_3=PMe_3, PEt_3, PMePh_2$, 1/2 DPPE, 1/2DPPB) (3a${\sim}$3e). Chloride complexes (2a${\sim}$2f) and hydride complexes (3a${\sim}$3e) were isolated as crystals, which were characterized by IR, $^1H-NMR$ , and elemental analysis.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2984-2988
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• 2009

A gene (PH0311) encoding a hypothetical protein from the genome sequence data of the hyperthermophilic archaeon Pyrococcus horikoshii OT3 was cloned and over-expressed in Escherichia coli. The purified recombinant protein was found to possess FAD-dependent NADH oxidase activity, although it lacked sequence homology to any other known general NADH oxidase family. The product of the PH0311 gene was thus designated PhNOX (NADH oxidase from Pyrococcus horikoshii), with an estimated molecular weight of 84 kDa by gel filtration and 22 kDa by SDS-PAGE, indicating it to be a homotetramer of 22 kDa subunits. PhNOX catalyzed the oxidation of reduced ${\beta}$-NADH with subsequent formation of $H_2O_2$ in the presence of FAD as a cofactor, but not ${\alpha}$-NADH, ${\alpha}$-NADPH, or ${\beta}$-NADPH. PhNOX showed high affinity for ${\beta}$-NADH with a Km value of 3.70 ${\mu}$M and exhibited optimum activity at pH 8.0 and 95$^{\circ}C$ as it is highly stable against high temperature.

• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.382-393
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• 2017

In this study, it studies about Phytosphingosine (PhS) and Phytosphingosine-1-phosphate(PhS1P), and it tries to confirm the effect through anti-inflammatory, anti-melanin, MMP-1 revelation inhibition, and Western blot analysis experiment after grasping toxicity about 3 cells by using B16F10 melanin cell, RAW264.7 macrophage, and HDF fibroblast in order to find out whether it is possible to use as cosmetic material or not by studying biological activity in terns of skin care. As a result of this experiment, it confirmed that toxicity about B16F10, RAW264.7, HDF cell is low, and PhS1P appeared stronger inhibition activity than PhS in anti-inflammatory NO inhibitory activity experiment. MMP-1 revelation was greater in PhS1P, and it confirmed that the mechanism is due to reduction in ERK activity. On the other hands, melanin generation inhibitory activity is better than arbutin, and it confirmed that the mechanism is due to inhibition of revelation of MTF and Tyrosinase. In a nutshell, PhS and PhS1P that are bioactive substance may confirm the possibility to be used as functional cosmetic for wrinkle and skin improvement of whitening cosmetic.

• Bulletin of the Korean Chemical Society
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• v.29 no.3
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• pp.627-640
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• 2008

The geometrical structures, atomic charges, and relative energies of tetracoordinated Pd complexes [PdCl3Z (Z = Cl-, Br-, OH?-, H2O, NH3, PH3), PdCl2Z2 (Z = Br-, OH?-, H2O, NH3, PH3), PdZ?2X (Z = Cl-, OH?-, H2O, NH3, PH3; X = oxalate, O2-?CCO2-), and PdZ2Y (Z = Cl?-, OH?-, H2O, NH3, PH3; Y = succinate, CO2-?CHCHCO2-?)] and the ligand exchange reactions of the Pd complexes were investigated using the ab initio second order Mller-Plesset perturbation (MP2) and Density Functional Theory (DFT) methods. The geometrical characteristics of the tetracoordinated Pd(II) complexes with mono- and bidentate ligands, the effects of the atomic charges for the charged and uncharged ligands, the (dz2-p ) interactions between the dz2-orbital of Pd(II) and the p -orbital of bidentates, and the relative stabilities between the isomers of PdCl2Z2 and PdZ2Y were investigated in detail. The potential energy surfaces for the ligand exchange reactions used for the conversions of {[PdCl2(NH3)2] + H2O} to {[PdCl(NH3)2(H2O)]+ + Cl?-?} and {[PdCl2(PH3)2] + H2O} to {[PdCl(PH3)2(H2O)]+ + Cl?-?]} were investigated. The geometrical structure variations, molecular orbital variations (HOMO and LUMO), and relative stabilities for the ligand exchange processes were also examined quantitatively.

• The Korea Journal of Herbology
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• v.20 no.3
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• pp.93-100
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• 2005

Objective : Patriniae Herba (PH) has long been used as a remedy for treating infectious diseases in Korea. In the present experiments, the author examined the effects of PH on the cholecystokinin-octapeptide (CCK)-induced acute pancreatitis (AP) in rats. Methods : Male Wistar rat weighing 200 to 250 g were divided into three groups. Normal untreated group, in treatment with PH group; PH (1g/kg) was administered orally, followed by $75\;{\mu}g/kg$ CCK subcutaneously three times, after 1, 3 and 5 h. This whole procedure was repeated for 5 days. In treatment with saline group, the protocol was the same as in treatment group with PH. The author determined the pancreatic weight/body weight ratio, the levels of pancreatic HSP60, HSP72 and the secretion of pro-inflammatory cytokines. Methods : Repeated CCK treatment resulted in the typical laboratory and morphological changes of experimentally induced pancreatitis. PH was significantly decreased the pancreatic weight/body weight ratio in CCK-induced AP. Futhermore, the author demonstrated that PH increased HSP60 and HSP72 compared with CCK-induced AP. Additionally, the secretion of $TNF-{\alpha},\;IL-1{\beta}$ and IL-6 the levels of amylase and lipase were lower than that saline. Conclusions : These results suggest that PH may has a inhibitory effect against CCK-induced AP.

• Earthquakes and Structures
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• v.26 no.3
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• pp.175-189
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• 2024

Aiming at studying the plastic hinge (PH) evolution regularities and failure mode of rocking wall moment frame (RWMF) structure in earthquakes, the whole-working history analysis of seismic performance state of RWMF structure based on co-operation performance and PH evolution was carried out. Building upon the theoretical analysis of the elastic internal forces and deformations of RWMF structures, nonlinear finite element analysis (FEA) methods were employed to perform both Pushover analysis and seismic response time history analysis under different seismic coefficients (δ). The relationships among PH occurrence ratios (R_ph), inter-story drifts and δ were established. Based on the plotted curve of the seismic performance states, evaluation limits for the R_ph and inter-story drifts were provided for different performance states of RWMF structures. The results indicate that the R_ph of RWMF structures exhibits a nonlinear evolution trend of "fast at first, then slow" with the increasing of δ. The general pattern is characterized by the initial development of beam hinges in the middle stories, followed by the development towards the top and bottom stories until the beam hinges are fully formed. Subsequently, the development of column hinges shifts from the bottom and top stories towards the middle stories of the structure, ultimately leading to the loss of seismic lateral capacity with a failure mode of partial beam yield, demonstrating a global yielding pattern. Moreover, the limits for the R_ph and inter-story drifts effectively evaluate the five different performance states of RWMF structures.