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The optical properties and the carrier dynamics of CaSrSiO4:Eu3+ phosphors synthesized by using a solid-state reaction method have been studied by means of scanning electron microscopy, X-ray diffraction, photoluminescence (PL), PL excitation, time-resolved PL, and PL quantum-yield measurements. The phosphor synthesized with a Eu concentration of 5% and sintered at 1380 °C for 2 h in air showed a high quantum yield of 88.53% and good CIE chromaticity coordinate values. The strong excitation bands observed at 395 nm (7F0-5L6) and 466 nm (7F0-5D2) lead to an intense 5D0-7F2 transition (614 nm). The forbidden transitions (5D0-7F0 and 5D0-7F2) were observed and showed lifetimes shorter than that of the magnetic dipole transition (5D0-7F1).

A series of new double perovskite tungstate Ba2CaWO6:xDy3+ (0.01 ⩽ x ⩽ 0.15) phosphors were synthesized via solid state reaction process. XRD analysis confirmed the phase formation of Ba2CaWO6:Dy3+ materials. The photoluminescence excitation and emission spectra, concentration effect, thermal-quenching, and decay property were investigated. The phosphor could be excited by the UV light region from 250 to 400 nm, and it exhibits blue (493 nm) and yellow (584 nm) emission corresponding to 4F9/2–6H15/2 transitions and 4F9/2–6H13/2 transitions, respectively. The optimum dopant concentration of Dy3+ ions in Ba2CaWO6:xDy3+ is around 5 mol% and the critical transfer distance of Dy3+ is calculated as 14 A. The thermal-quenching temperature is 436 K for Ba2CaWO6:0.05Dy3+. The fluorescence lifetime is also determined in Ba2CaWO6:0.05Dy3+.

A novel and facile synthetic approach has been trialed, and attempted with success in the preparation of two phosphors namely, a red emitting CaSrSiO4:Eu3+ and a green emitting CaSrSiO4:Eu2+. These phosphors were successfully synthesized using a simple co-precipitating solvo-thermal strategy wherein tetraethyl orthosilicate (TEOS) as silica source and the acetate precursors of strontium (Sr2+), calcium (Ca2+) and europium (Eu3+) are utilized. The material so obtained is subjected to an extensive photoluminescence behavior study. The concentration of the dopant (Eu3+and Eu2+) plays a significant role in the determination of photoluminescence behavior and hence a systematic and in-depth experimental studies were done and the results are synchronized. On interpretation of the output, it came to light that an intense emission signals sparked in the red region (590 and 615 nm) in the case of phosphor doped with Eu3+, which is excited under near ultra violet (395 nm) and blue (466 nm) region. In case of the CaSrSiO4 sample doped with Eu2+, an intense broad green signal (~510 nm) is obtained under the excitation range of 350–430 nm. The results obtained are quite encouraging and made a strong confirmation as, the solvo-thermally synthesized CaSrSiO4, which is activated by the dopants namely Eu3+ and Eu2+ possesses an immense potential and it is exactly tapped by the adopted methodology. Despite its strong impact, it will also assure a strong revolution in the fabrication and thus the commercialization of white LEDs as both the red and green emitting phosphor.

Novel host-sensitized Y6WO12:xDy3+ (0.01 ≤ x ≤ 0.20) phosphors were synthesized via solid-state reaction process. X-ray diffraction analysis confirmed the phase formation of Y6WO12:Dy3+ materials. The photoluminescence excitation and emission spectra, concentration effect, thermal-quenching, and decay properties were investigated. The phosphor could be excited by the UV light region from 300 to 400 nm, and it exhibited blue (478 nm) and yellow (568 nm) emission corresponding to 4F9/2–6H15/2 transitions and 4F9/2–6H13/2 transitions, respectively. The WO6 groups in the host lattices can absorb UV light efficiently, and then transferred the energy to the activator Dy3+ ions, resulting in near white light emission. The optimum dopant concentration of Dy3+ ions in Y6WO12:xDy3+ was around 5 mol% and the critical transfer distance of Dy3+ was calculated as 12 A. The fluorescence lifetime was also determined in Y6WO12:0.05Dy3+. The temperature dependence of photoluminescence properties was investigated from 300 to 480 K and the prepared Y6WO12:Dy3+ phosphors showed poor thermal-quenching properties.

A series of benzofuran-2-carboxamides of biological and medicinal significance were synthesized by a microwave-assisted one-pot parallel approach via O-alkylation/Knoevenagel condensation. All the compounds were characterized and assayed for their in vivo anti-inflammatory, analgesic and antipyretic activities. The activity data of all compounds were listed and discussed in detail, among which some derivatives exhibited potent activities of particular interest.

We investigate the current-dependent and temperature-dependent efficiency droops ("J-droop" and "T-droop", respectively) in InGaN-based blue and AlGaInP-based red light-emitting diodes (LEDs). It is found that the blue and red LEDs show different droop behaviors with increasing current density and temperature. The J-droop is significant in the blue LED while the T-droop is severe in the red LED. In case of the blue LED, the carrier accumulation caused by the saturation of the radiative recombination rate is thought to increase the quasi-Fermi level rapidly, thus causing the J-droop. On the other hand, the T-droop of the red LED is influenced by redistribution of carriers due to the increased thermal energy with a small barrier height in the AlGaInP material system. The comparison of different droop characteristics of blue and red LEDs helps understand the recombination mechanisms of both LEDs and provides useful insight for improving the device performance further.

The Er 3+ -doped novel oxyfluoride glasses of composition (43 − x )SiO 2 –10Al 2 O 3 –24LiF–23SrF 2 – x Er 2 O 3 , where x = 1.0, 2.0, 4.0 and 6.0 mol%, have been prepared by conventional melt quenching technique and are characterized through X-ray diffraction (XRD), differential thermal analysis (DTA), Raman, Fourier transform infrared (FT-IR) analysis, optical absorption spectra, visible (vis) and near-infrared (NIR) emission spectra measurements. Judd–Ofelt (JO) intensity parameters ( Ω λ , λ = 2, 4 and 6) have been derived from the absorption spectrum of 1.0 mol% Er 2 O 3 doped glass and are in turn used to calculate radiative properties for the important luminescent levels of Er 3+ ions. The studied glasses show intense green and weak red visible emissions under 365 nm excitation. The decrease in visible emission intensities with concentration of Er 3+ ions has been explained due to energy transfer processes between Er 3+ ions. Upon excitation at 980 nm laser diode, an intense 1.53 μm NIR emission has been observed with the maximum full width at half maximum (FWHM) for Er 3+ -doped oxyfluoride glasses. The higher Er 3+ ion doping capability and relatively high gain and broad emission at 1.5 μm are the most notable features of these glasses to realize efficient short-length optical amplifiers.

Department of Chemistry, Changwon National University, Changwon, GN 641-773, Korea. E-mail: dsshin@changwon.ac.kr Department of Physics, Changwon National University, Changwon, GN 641-773, Korea KIP, Hanbat National University, Yuseong, Daejeon 305-719, Korea Department of Chemistry & Research Institute of Natural Sciences, Gyeongsang National University, Jinju, GN 660-701, Korea Received August 1, 2013, Accepted October 5, 2013

This study outlines a novel approach to the synthesis of an efficient yellow-emitting Sr0.975Ca0.975Eu0.05SiO4 phosphor with the adequate red spectral components. This was achieved by the use of a well-known silicate source, mesoporous silica. The findings showed that the synthesized phosphor gave a broad emission from blue to red, along with a stable emission color till 450 K and an emission decay time of 1 μs. When the phosphor was fabricated using UV (400 nm) and blue LED (450 nm) chips, it promisingly generated warm white light at a color temperature 80.

The design and synthesis of hemi-fluorinated perfluorooctanesulfonic acid (PFOS) alternatives is described using a Zn/CuI mediated Michael-type addition reaction in ionic liquids considering environmentally benign reaction conditions as well as products. One of the new potassium sulfonates showed promising surface tension activities when compared to that of the PFOS potassium salt.

Department of Chemistry, Gyeongsang National University, Chinju 660-701, KoreaReceived July 3, 2013, Accepted September 20, 2013Key Words : C-N coupling, Smiles rearrangement, 6-Aminoquinoline, 6-Hydroxylquinoline, One-potAminoquinolines and their derivatives are importantchemical entities that are widely used as pro-drugs and drugsdue to their antimicrobial, cytotoxic and anti-malarialactivities etc.

Objective To examine the psychometric properties of a structured self-reported 8-item Korean-version Morisky Medication Adherence Scale (MMAS-K) among rural older adults with hypertension. Design Cross-sectional descriptive survey. Setting A rural community comprising three primary health care posts in Gangwon Province, South Korea. Participants Ninety-two older adults with hypertension who received treatment at primary health care posts. Main outcome measures Participants completed an 8-item MMAS-K questionnaire, and the community health practitioners manually measured blood pressure. Factor analysis and correlation coefficient for validity and the Kuder–Richardson alpha coefficient for reliability of the MMAS-K were used, while the association between medication adherence and blood pressure control was determined using Fisher's exact test. Results Internal consistency reliability was acceptable with a coefficient alpha of 0.71. The factor analysis of construct validity identified two dimensions of the 8-item MMAS-K, explaining 52.22% of the total variance. There was a high correlation between the 8-item MMAS-K and the original 4-item MMAS (r = 0.874), indicating that these scales measure theoretically related constructs for convergent validity. There was a significant association between the 8-item MMAS-K score and blood pressure control (P

We demonstrate a method of systematic analysis for the photocurrent spectroscopy on InGaN/GaN light-emitting diodes (LEDs). By normalizing photocurrent data at a photon energy of 3.2 eV for blue LEDs, we show that accurate comparison of active quantum wells is possible. Bias-dependent photocurrent measurements reveal that there are fixed points in photocurrent data from which an effective bandgap energy can be determined. The method presented in this paper can be useful when one needs to compare the LEDs fabricated at different times or by different processes.

Single crystalline pure and rare-earth metal ions (Eu3 + and Ce3 +) doped TiO2 nanowire arrays were prepared on conductive fluorine doped indium tin oxide substrates by a facile hydrothermal method. Initially the conditions and parameters were optimized to prepare the high quality TiO2 nanowire arrays in the absence of organic additives. The average diameter and length of the TiO2 nanowire were found to be ~ 30–50 nm and ~ 0.5–1.5 μm, respectively. The formations of rutile phase structure in all the samples were confirmed by x-ray diffractometric analysis while the transmission electron microscopy confirms the single crystallinity and the maximum orientation of growth direction along [001] for the as-grown TiO2 nanowire. The optical properties of all the samples were analyzed using photoluminescence spectroscopy. The photocatalytic properties of the pure and doped TiO2 were investigated for the decomposition of organic toludine blue-O dye under ultraviolet irradiation. The result demonstrates that the Ce3 +: TiO2 decomposed almost 90% of the organic dye within 80 min.

A rare-earth metal ion (Eu3+) doped ZnO nanocomposites have been successfully synthesized by employing wet chemical procedure using multi-wall carbon nanotubes (MWCNT's) as removable template. The preparation was carried out by immersing empty and dried MWCNT's in a stoichiometric composition of zinc nitrate and europium nitrate solution followed by filtration and sintering. The synthesized Eu3+ doped ZnO nanocomposites were characterized by means of different characterization techniques namely XRD, SEM, EDS, FT-IR and Raman spectroscopy. The XRD profile of the Eu3+ doped ZnO nanocomposites indicated its hexagonal nature while the photoluminescent analysis reveals that the prepared nanocomposite exhibits a strong red emission peak at 619 nm due to 5D0 --> 7F2 forced electric dipole transition of Eu3+ ions. Such luminescent materials are expected to find potential applications in display devices.

A convenient one-pot synthesis of phenols to anilines using 2-chloroacetamide/K2CO3/DMF system catalyzed by KI via Smiles rearrangement has been described. The synthesis of extensive amino aromatic products from phenols containing electron withdrawing group, has been performed in moderate to excellent yields to demonstrate the potentiality of this method in bio-medicinal and pharmaceutical applications.

A correlation between the efficiency droop and the blueshift of the peak wavelength in electroluminescence is experimentally investigated by utilizing InGaN/GaN multiple-quantum-well blue light-emitting diodes with different efficiency droop characteristics. We experimentally observe a clear correlation between these physical quantities and explain it by the increased inhomogeneity of indium incorporated into the InGaN quantum wells (QWs). With more indium in the QWs, the effective active volume becomes smaller due to indium clustering, inducing early saturation of the radiative recombination rate and subsequent droop.

Recently meteorological phenomena caused by climate change have brought localized heavy rainfalls, flash-floods causing severe damage for human-life and property. They also increase the occurrence of record-breaking rainfall. Development in urban area decreases the portion of open spaces, landscapes, leading to significant diminution of storage and detention function of the basin. The expansion of impervious areas increases the extent of peak-runoff and runoff volume, especially the shorter time of concentraion due to development makes the basin have different hydrological characteristics compared to pre-development. In addition, urbanization worsen the requirement of site for residence and public facility so that even floodplain and inundated district are urbanized threatening safety for flood control. In this study, applicable LID techniques are analyzed and implemented using LID modules of SWMM, which is the model for urban stormwater-runoff management in the project area. Effects of implementing LID practices are also assessed and reviewed. The result shows that scenario B and C ruduced 288.52ton(15.62%), 240.26ton(13.01%) each in runoff simulations compared to scenario A.

Porphyrin-POSS hybrid: Porphyrin-POSS molecular hybrid composites (see scheme; POSS = polyhedral oligomeric silsesquioxanes) were synthesized and structurally characterized, allowing the realization of truly homogenous dispersion of basic functional building blocks between organic and inorganic components at the molecular level. These materials allow the optimization of aggregation/association behavior and thus the functional optical properties of the porphyrinato zinc compounds.

MIC-3500을 각 농도별(4, 8, 10, 15 그리고 20%)로 조제하여 마이크로웨이브 조사 후 각 농도별로 흡광도를 나타냈었다. 측정결과 193−203 nm에서 peak가 나타냈으며,절삭유의 농도가 짙어질수록 흡광도가 증가하였고 또한파장(nm)이 길어지는 것을 확인하였다(Fig. 1).노르말-헥산법으로 추출된 오일에 흡광도를 측정하였다. 그 결과 노르말-헥산법으로 추출된 오일의 양이 많을수록 흡광도가 증가함을 알 수 있었다(Fig. 2).Table 1. The characters of water-soluble cutting oilCutting oil MIC3500 (BUHMWOO CHEMICAL) METOSOL506 (HANSUNG) EM-100 (SINCOOL)Color (undiluted/diluent) Brown, (milky) Dark green (green milky) Brown transparent, (milk white)Specific gravity (15/4

Al contents have been doped as a sensitizer to improve the luminescent brightness, and the conventional solid state reaction method has been used to synthesize the phosphors. Al doping effects on the microstructures of YVO4:Eu3+ phosphors were measured by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The luminescent characteristics were characterized by photoluminescence excitation (PLE) and emission (PL) measurements. Incorporation of Al3+ ions into the YVO4:Eu phosphors has greatly enhanced the crystallinity, particle size and hence the luminescence properties and the optimum concentration in Al dopants are found to be 0.05 mol. The photoluminescence intensity of 0.05 mol Al(3+)-doped YVO4:Eu3+ phosphors was improved by a factor of 1.41, in comparison with undoped Y0.95Eu0.05VO4 phosphor. The improvement in photoluminescence properties with Al doping may result from the improved crystallinity and from the enlarged grain sizes inducing lower scattering loss.

Eu3+ activated NaSr(P,V)O4 phosphors have been synthesized using solid state reaction method and further characterized for their structure and optical properties using different techniques such as X-ray diffraction, scanning electron microscopy, photolumniscenec excitation, emission, and chromaticity coorrdinate analysis, etc. Material shows a broad excitation peak (monitored for lambda(ems) = 613 nm) lying in the 300-360 nm region and gives intense transitions (lambda(exc) = 320 nm) namely 5D0 --> 7F1 at 590 nm, 5D0 --> 7F2 at 613 nm, 5D0 --> 7F3 at 650 nm, and 5D0 --> 7F4 at 700 nm due to Eu3+ ion. Our results show that replacement of the PO4(3-) ions with isomorphic VO4(3-) ions improves the structural stability and the overall intensity of the emission. The maxium emission intensity is achieved for the NaSr(P0.4, V0.6)O4:Eu3+ phosphor. An estimated increase of an order is attained for the NaSr(P0.4, V0.6)O4:Eu3+ phosphor as compared to NaSrPO4:Eu3+ or NaSrVO4:Eu3+ phosphor. The chromaticity coordinate of the phosphor (0.68, 0.31) lies well within the red region and suggest that the material could be an alternative red phosphor for lighting and display applications.

In this present work, we have developed a novel POSS type monomer ligand “2,6-pyridinediamine-bis-(propanylheptaisobutyl POSS)” (PDC-POSS) and utilized in the preparation of potential luminescent hybrid complex Eu-PDC-POSS with an inner transition metal ion Eu3+. The solubility and photo-emitting properties of new Eu-PDC-POSS hybrid material were studied. The precursor PDC-POSS was synthesized by treating (3-aminopropyl)heptaisobutyl POSS with PDC (2,6-pyridinedicarboxylic acid chloride), and then coordinated with Eu3+ using europium nitrate to afford Eu-PDC-POSS hybrid material. The europium-doped hybrid material was characterized using fourier transform infrared spectroscopy, and scanning electron microscopy along with energy dispersive X-ray analysis. The photo emitting properties were studied using a fluorescence spectrophotometer in which, the results showed enhancement in red emission peak at 618 nm for Eu-PDC-POSS, when compared to that of a known solgel-based material Eu-PDC-solgel.

In InGaN-based light-emitting diodes (LEDs), carrier leakage to the outside of the active quantum wells (QWs) has been considered as one of the dominant carrier loss mechanisms at high current densities. In order to verify the carrier spill-over phenomenon, we compared the electroluminescence (EL) efficiency, the resonant photoluminescence (PL) efficiency, and the open-circuit voltage as functions of current, temperature, and excitation laser power. Very similar tendencies were experimentally observed among the three physical quantities, which implied that carriers were spilt over out of the QWs even in the resonant PL experiment.

An efficient green emitting Tb 3+ doped NaCaPO 4 (NCP) phosphor was synthesized by using conventional solid-state reaction for solid-state lighting applications. X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), FT-IR, emission and excitation properties were extensively investigated for NCP phosphors. X-ray diffraction analysis confirmed the formation of NaCaPO 4 with orthorhombic structure. The excitation spectrum consists of strong 4f–4f transition at around 370 nm, which has higher intensity than the f–d transition. Emission spectra indicated that this phosphor can be efficiently excited by UV light in the range from 250 to 400 nm, and shows strong emission band centered at 547 nm. Analysis of the emission spectra with different Tb 3+ concentrations revealed that the optimum dopant concentration for these NCP phosphors is about 5 mol% of Tb 3+ . Diminishing of 5 D 3 level and increasing of 5 D 4 level emission intensity with the Tb 3+ concentration explained successfully. The emission color was analyzed and confirmed with the help of chromaticity coordinates and color temperature. The excellent luminescent properties of NaCaPO 4 :Tb 3+ phosphor makes it as a potential green phosphor upon near-UV LED excitation.

Eu3+ doped K2La2Ti3O10 (KLT) phosphors were prepared by means of conventional solid state reaction method. It has exhibited an intense excitation band at around 466 nm, which matches well to the popular emission line from a GaN based blue light-emitting diode (LED) chip. Using this as an excitation wavelength the Eu3+ doped KLT phosphors yielded two strong orange-red emission bands at 595 nm (5D0→7F1) and 616 nm (5D0→7F2) respectively. The obtained results suggest that Eu3+doped KLT phosphors are useful for blue chip white LEDs. Besides we have studied its dielectric properties along with the other significant characterizations like XRD, SEM and Tg-DTA.

We investigate the effect of a strain relaxation layer (SRL) on the internal-field measurement of InGaN/GaN multiple quantum wells (MQWs) in blue light-emitting diodes by using electroreflectance (ER) spectroscopy. The polarization charges of the SRL are relatively smaller than those of the MQWs because the SRL has a lower indium composition in the InGaN/GaN superlattice. Therefore, the phases of the ER signals from the MQWs and the SRL are reversed at different bias voltages. From two different compensation voltages, the piezoelectric fields in MQWs and the SRL are estimated separately. When the SRL is not considered, the piezoelectric field in the MQWs can be underestimated.

Eu3+ doped Gd2O3 nanotubes have been synthesized using multi wall carbon nanotubes as removable templates by employing a liquid phase deposition method. The prepared Eu3+ doped Gd2O3 nanotubes were characterized by means of x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy, fourier transform infrared sepctroscopy and thermogravimetry and differential thermal analysis. XRD patterns conrm the cubic phase of Eu3+ doped Gd2O3 nanotubes. From the measured SEM images, the average diameter of the Eu3+: Gd2O3 nanotubes were estimated to be in the range of 50–70 nm. The photoluminescence analysis revealed that the Eu3+: Gd2O3 nanotubes can display a strong red emission peak at around 616 nm, due to the 5D0→7F2 electric dipole transition of Eu3+ ions. Such luminescent powders are expected to find potential applications in fluorescent lamps and display device applications.

An procedure for the definition of rainfall threshold value is illustrated in order to develop optimal flood forecasting and warnings systems for small river basins. Threshold overcoming could produce a danger situation in river sites and trigger the prevention and emergency system alert. Rainfall threshold values is based both on the quantitative rainfall observed and the hydrological response of the small river basin. Threshold values specify the rainfall amount for a given duration that generates a danger discharge in a outlet's cross section and are estimated by hydrological modeling for several scenarios(e.g, Soil Moisture conditions, Initial Abstraction). Nakdong River basin is separated to 2,268 small river basins by using Hec-GeoHMS, rainfall threshold for small river basins are presented for several scenarios.

A series of newer substituted-imidazolidine derivatives 3ak were synthesized and assayed in vivo to investigate their anti-inflammatory, analgesic and antiulcer activity. The results of biological evaluation revealed that the three compounds, 4- (1,3-bis(4-hydroxy-3-methoxybenzyl)-2-imidazolidinyl)phenyldiethylamine (3g), 4-(1,3-bis(3-Ethoxy-4-hydroxybenzyl)-2-imida- zolidinyl)phenyldiethylamine (3h) and 4-(1,3-bis(benzo(d)(1,3)dioxol-5-ylmethyl)-4-methylimidazolidin-2-yl)-N,N-diethyl- benzenamine (3j) were good in their anti-inflammatory and analgesic actions. Additionally these derivatives showed superior GI safety profile as compared to that of the standard drug in terms of low severity index. The results are statistically treated for its significance.

The one-pot regioselective consecutive multihalogenation of 2,2′-bithiophene (1) was demonstrated. Compound 1 was consecutively halogenated with lithium halides such as lithium bromide, chloride, and/or iodide in the presence of lead tetraacetate in chloroform at room temperature or under reflux conditions to give 5-bromo(or chloro)-5′-iodo(or chloro)-, 3-bromo(or chloro)-5,5′-dibromo(or dichloro, diiodo)-, 3,3′-dibromo-(or dichloro)-5,5′-diiodo(or dibromo, dichloro)-, and 3,3′,5-tribromo(or trichloro)-5′-iodo(or bromo)-2,2′-bithiophenes. Notably, this process offers a regioselective method for consecutive multihalogenation in one pot, and the yields and selectivity are also higher than those obtained in the step-by-step and concurrent halogenation methods.

Efficient and green syntheses of heterocycles are of great importance. In this work, we have demonstrated the synthesis of benzo[d]thiazoles and benzo[d]oxazoles using 2-acylpyridazin-3(2H)-ones as acyl transfer agents under transition-metal-free and eco-friendly conditions. It is worthy to note that the reaction is efficient, green, and economical, and will find several applications in organic synthesis, medicinal chemistry, and industrial chemistry.

Department of Chemistry, Gyeongsang National University, Chinju 660-701, KoreaReceived October 10, 2012, Accepted November 29, 2012Optically active N-benzyl-2-methyl-2H-benzo[b][1,4]oxazin-3(4H)-ones and N-benzyl-2-methyl-2H-benzo[b][1,4]thiazin-3(4H)-ones with potential synthetic and pharmacological interest were prepared via Smilesrearrangement in conventional as well as microwave irradiation conditions in one-pot from inexpensive ( S)-2-chloropropionic acid. Most of the compounds displayed good inhibition against Gram positive bacteria andfungi in the antibiotic test.Key Words : Oxazinones, Thiazinones, Smiles rearrangement, Microwave irradiation, AntibioticIntroduction1,4-Benzoxazinones and 1,4-benzothiazinones are fasci-nating tools present in clinically significant pharmaceuticalsand other biologically active molecules. Compounds con-taining 2H-benzo[b][1,4]-oxazin-3(4 H)-one moiety are wellknown to show wide biological activities such as beingantiulcer

E-mail: dsshin@changwon.ac.kr Received September 8, 2012, Accepted November 8, 2012An efficient process for the synthesis of N-azaaryl anilines via Smiles rearrangement as a tool. A variety of N-azaaryl anilines were generated by the reaction of substituted phenols, substituted anilines, aminopyridines andchloroacetyl chloride or pyridols, under base condition in good to excellent yields.Key Words : Smiles rearrangement, N-Azaaryl anilines, Amine, Phenol, SynthesisIntroductionThe pyridine ring system appears to be indispensable inthe structures of various natural products, pharmaceuticalcompounds, and other commercial substances. With pyri-dine ring in the structures, N-azaaryl anilines have attractedconsiderable attention owing to their wide range of bio-logical activities, such as antimicrobial

To examine the mediating role of occupational stress on the relationship of anger expression to cardiovascular disease (CVD) risk using Framingham risk score equation in Korean adults with metabolic syndrome.This cross-sectional study was a secondary analysis of baseline data from a longitudinal study conducted in 91 Korean male workers. Psychological variables were assessed using structured questionnaires.Occupational stress was significantly predictive of CVD risk (β=.278, p=.008). The inclusion of occupational stress non-significantly decreased the standardized beta by 33.6% for anger expression as a predictor of CVD risk (β=.152, p=.163). The Sobel test showed a significant mediating effect between occupational stress and CVD risk (plt;0.01).This mediating role of occupational stress has important clinical implications as interventions designed to manage anger expression to reduce CVD risk in this population.

Objectives To identify factors associated with mortality in patients treated with veno-arterial extracorporeal membrane oxygenation (VA-ECMO) and to validate the discrimination of the risk assessment tools to predict mortality. Background VA-ECMO is a rescue therapy for patients with life-threatening cardiac failure, but mortality remains high. Methods In this retrospective study, we reviewed the medical records of adult patients who underwent VA-ECMO in an intensive care unit of a university hospital, between 2009 and 2013. Results VA-ECMO was performed in 89 patients, with a median duration of 116 h. The survival rate until hospital discharge was 27%. The pre-ECMO simplified acute physiology score (SAPS) II and diabetes mellitus were significant predictors of hospital mortality. The optimal prognostic SAPS II score was 81 overall, 80 in patients with diabetes, and 84 in those without diabetes. Conclusions Our findings indicate that high pre-ECMO SAPS II score and diabetes are risk factors for mortality in patients who undergo VA-ECMO.

Alkaline earth metal gallets have been identified as an important ceramic material. The crystal chemistry of many of these gallets is well explored; however, very rare studies regarding optical properties of rare earth (RE) ions doped in such gallets, particularly in Sr 3 Ga 2 O 6 host, have been carried out. The present study reports on synthesis and characterization of novel Sr 3 Ga 2 O 6 :Eu 3+ phosphors. The phosphors have been synthesized using a conventional solid state reaction method. Crystal structure, morphology and luminescence properties (excitation, emission and CIE coordinate) of these phosphors have been studied as a function of sintering temperature and Eu 3+ concentration. X-ray diffraction study reveals that the phosphor sintered at low temperature (900 °C) contains an impurity phase which is removed at higher sintering temperatures and results into cubic crystalline phase of Sr 3 Ga 2 O 6 . Particle size of the phosphor increases with an increase in sintering temperature which results to a red shift in the peak position of excitation band lying in a broad range from 250 to 370 nm. Optimum emission intensity is attained for 0.12 mol% concentration of Eu 3+ ions; above this concentration, a quenching in emission intensity is observed.

This paper reports on the photoluminescence properties of Na 1− y Li y Ca 1− x PO 4 : x Eu 2+ phosphors synthesized by a solid state reaction method. The prepared phosphors have been thoroughly characterized by means of X-ray diffraction (XRD), Field-emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectrum (FTIR), Raman spectrum, Thermo gravimetric and differential thermal analysis (TG–DTA) and photoluminescent spectral measurements. The structure of Na 1− y Li y Ca 1− x PO 4: x Eu 2+ phosphors were found to be orthorhombic in nature with a sphere-like morphology and having the particle size in micrometer range. The excitation spectra of NaCaPO 4 :Eu 2+ phosphors revealed a broad excitation band having its maximum intensity at 373 nm and ranging from 250 m to 450 nm. Incidentally, it matches well with the ultraviolet (UV) radiation of light-emitting diodes (LEDs). Upon 373 nm excitation, these phosphors exhibited intense bluish-green emission band centered at 505 nm. The effect of sintering atmospheres and co-doping of lithium ions on the photoluminescence properties of the NaCaPO 4 :Eu 2+ phosphors were studied and explained suitably. The obtained results indicate that the prepared NaCaPO 4 :Eu 2+ phosphors are promising bluish-green candidates for the phosphor-converted white LED applications.

E-mail: dsshin@changwon.ac.krReceived May 29, 2012, Accepted August 1, 2012A number of novel small molecules, safrole oxide derivatives 4a-c, 6a-c, 9a-h, were synthesized by the reactionof safrole oxide with anilines 3 and 5, or its alkyl allyl ether derivative 7 with alkyl bromide 8 in moderateyields. The antiproliferative effects of all the target molecules on A549 cell growth were investigated and it wasfound that the 14 novel compounds could suppress A549 lung cancer cell growth. Among them, compound 6bwas the most effective compound in inhibiting the proliferation of A549 cells.Key Words : Safrole derivatives, A549 cells, MTT assay, Growth inhibitionIntroductionLung cancer is the leading cause of cancer-related morta-lity in the developed countries, accounting for 26-28% of allcancer deaths.

Two new series of benzimidazole bearing oxadiazole[1-(1H-benzo[d]imidazol-2-yl)-3-(5-substituted-1,3,4-oxadiazol-2-yl)propan-1-ones (4a-l)] and triazolo-thiadiazoles[1-(1H-benzo[d]imidazol-2-yl)-3-(6-(substituted)-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazol-3-yl)propan-1-one (7a-e)] have been synthesized successfully from 4-(1H-benzo[d]imidazol-2-yl)-4-oxobutanehydrazide (3) with an aim to produce promising anticancer agents. In vitro anticancer activities of synthesized compounds were screened at the National Cancer Institute (NCI), USA, according to their applied protocol against full NCI 60 human cell lines panel; results showed good to remarkable anticancer activity. Among them, compound (4j, NCS: 761980) exhibited significant growth inhibition and further screened at 10-fold dilutions of five different concentrations (0.01, 0.1, 1, 10 and 100 μM) with GI(50) values ranging from 0.49 to 48.0 μM and found superior for the non-small cell lung cancer cell lines like HOP-92 (GI(50) 0.49, TGI 19.9,LC(50) >100 and Log(10)GI(50) -6.30, Log(10)TGI -4.70, Log(10)LC(50) >-4.00).

The effects of Dy, Mn alone doping and co-doping on the structural, electrical and ferroelectric properties of BiFeO3 thin films were investigated. (Bi1−x Dy x )(Fe1−y Mn y )O3 thin films, with (x, y) = (0, 0), (1, 0), (0, 1), and (1, 1) denoted by BFO, BDyFO, BFMnO, and BDyFMn, respectively, were prepared by using a chemical solution deposition method. All thin films were annealed at 550 °C for 30 min by using a conventional annealing process under a nitrogen atmosphere for crystallization. Among the thin films, superior ferroelectric properties were observed in the BDyFMn thin film. The BDyFMn thin film exhibited a low leakage current density (1.8 × 10−5 A/cm2), well-saturated hysteresis loops, a large remanent polarization (2P r ) of 80 µC/cm2 (at a 1060-kV/cm applied electric field) and good fatigue endurance.

Present study deals with Eu3+ activated novel alkaline earth metal (Sr and Ca) gallium oxide phosphors, Sr(2.92−x)Ca(x)Ga2O6:Eu3+0.08 (x = 0 to 2.92). Crystal structure, morphology and luminescence (excitation, emission and CIE coordinate) properties of these phosphors have been studied as a function of Ca concentration. Doping of Ca ions into Sr2.92Ga2O6:Eu3+ phosphor gives rise to a significant enhancement in overall fluorescence and the optimum emission is attained for pure Ca2.92Ga2O6:Eu3+ phosphor for x = 2.92. The intensity ratio of 5D0 → 7F2 to 5D0 → 7F1 transitions (monochromaticity) of Eu3+ for different doping concentration of Ca suggests that asymmetry around the Eu3+ ion increases with increase in Ca ion concentration, which is responsible for enhanced emission. The excellent optical features, such as broad excitation band (230–480 nm) and excellent emission in red region (at 614 nm), conclude that calcium gallet phosphor could be a potential candidate for light emitting diodes and display applications.

Variation of the urban functions on complex underground space development and increasing demand, and due to heavy rainfall caused by climate changing, flooding in complex underground space into a situation where the possibility of more increases to minimize flood damage in underground space for various requires measure to prevent flooding. In order to establish the optimal protect against flooding, a study uses the hydraulic and numerical model experiments, and each inundation measures the flow characteristics in an underground space required for the research and studies in a Korea, however, it has been little. In this study, the risk of flooding underground space in the presence of EPA SWMM model basin runoff analysis to build up complex underground space and the results were applied at a flow rate on flooding. Not only the study calculated the experimental value every scenario through checking whether there is storage facility or not, the installation of the sand bag and barrier wall by making the underground space of special building which mainly affected by the quantity of runoff in the object basin into hydraulic model, but also tried to analyze the flooding tendency of the underground by figuring out water level change of the Inundation.

Efficient one-pot microwave-assisted synthesis of various benzo-(1,4)-oxazinones via Smiles rearrangement is described. Treatment of 2-chloroacetamide, substituted 2-chlorophenols and cesium carbonate in MeO-PEG-OMe (2,000) as solvent afforded the corresponding benzo-(1,4)-oxazinones and 1H-pyrido(2,3-b)(1,4)-oxazin-2-(3H)-one as moderate yield.

Thixomolding of Mg-alloy is a semi-solid injection molding process utilizing thixotropic phenomenon. Using this process, higher strength, thinner wall section and tighter tolerance without porosity are obtained. It has been applied for production of near-net-shape magnesium component. To design optimal thixomolding process of Mg-alloy part, molding conditions such as slurry temperature, mold temperature and injection time should be determined properly. Selection of these parameters has been dependent upon engineers' experience and intuitiveness. In this paper, to improve mechanical properties of the thixomolded product, optimal selection of process variables such as injection velocity, barrel temperature and die temperature in the process has been studied through microstructural analysis and Taguchi method. Performance of the process is verified through experiments. Key Words : AZ91D, Mechanical property(기계적성질), Mg-alloy(마그네슘합금), Microstructure(미세조직), Semi-solid Injection(반응고주조), Thixotropy(틱소트로피)

An efficient synthetic strategy for the synthesis of diversely 2,3-disubstituted benzofurans is described. This method is based on the use of propargylic alcohols generated from TBS-protected ortho-hydroxy benzaldehydes as starting materials and allows a library of 2,3-disubstituted benzofurans to be built. The procedure consists of one-pot nucleophilic substitution, TBS-deprotection, and exo-dig cycloisomerization.

With the aim of discovering new molecules with potassium channel activating properties, we have designed and synthesized derivatives with structural similarity to cromakalim, an important molecule which shows specific affinity toward potassium channels, based on previous structure–activity investigations by applying different C-4 substitutions. This has been accomplished by using a stereoselective Jacobsen epoxidation and microwave assisted regioselective epoxide opening with neutral alumina as the key reactions.

The nonradiative recombination carrier lifetime in InGaN/GaN quantum wells was measured utilizing a time-resolved photoluminescence measurement. The lifetime was estimated from the final decay stage of the temporal response of the photoluminescence, which is closely related to the nonradiative recombination. The nonradiative recombination carrier lifetime estimated by using the given method showed of relative independence from the carrier density in the quantum well. A study comparing the nonradiative recombination carrier lifetime estimated by using the given method with the results of temperature-dependent photoluminescence and current-dependent electroluminescence measurements at room temperature we performed. This unique method can be very useful for measuring the nonradiative carrier lifetime with good accuracy within a short time.