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Three kinds of char catalysts were prepared by fluidized bed pyrolysis at the temperature range between 500 and 800 o C from lignite, subbituminous, and bituminous coal, and tested for their catalytic activities in the selective catalytic reduction of NO by NH 3 at 150 o C. Effects of pyrolysis temperature and oxygen presence in pyrolysis on the catalytic activity of char were investigated. The catalytic activity of NO reduction was found to be closely related to the surface area and the amount of oxygen functional groups. In the experimental range studied, higher catalytic activities were exhibited in accordance with higher surface area and larger amount of oxygen functional groups

Zeolite catalysts, having layered structure of ZSM-5 or borosilicate core covered with a silicalite shell, were prepared by hydrothermal crystallization of silicalite in the presence of ZSM-5 or borosilicate seeds. Characteristics of the prepared catalysts were examined by X-ray diffraction, scanning electron microscopy and temperature-programmed desorption. Comparison of these double-structured catalysts to ZSM-5 type catalysts, showed that they exhibited considerably higher para -selectivity in toluene alkylation reactions, but had slightly lower activity. The former showed higher para -selectivity at the same conversion level. This result suggests that para -selectivity could be enhanced by selectively inactivating the external acid sites without changing the pore mouth size.

Zeolite catalysts, having layered structure of ZSM-5 or borosilicate core covered with a silicalite shell, were prepared by hydrothermal crystallization of silicalite in the presence of ZSM-5 or borosilicate seeds. Characteristics of the prepared catalysts were examined by X-ray diffraction, scanning electron microscopy and temperature-programmed desorption. Comparison of these double-structured catalysts to ZSM-5 type catalysts, showed that they exhibited considerably higher para -selectivity in toluene alkylation reactions, but had slightly lower activity. The former showed higher para -selectivity at the same conversion level. This result suggests that para -selectivity could be enhanced by selectively inactivating the external acid sites without changing the pore mouth size.

A fast sol−gel synthetic route for obtaining alumina aerogels has been developed by modifying the tranditional method under appropriately controlled conditions. The highly mesoporous alumina aerogel prepared by our new sol−gel synthesis method and CO2 supercritical drying had a surface area in excess of 700 m2/g and high thermal stability.

We report on the M\"ossbauer spectra and magnetization properties of single-crystalline ${({\text{BiFeO}}_{3})}_{x}\text{\ensuremath{-}}{({\text{BaTiO}}_{3})}_{1\ensuremath{-}x}$ solid solution nanostructures in the form of nanocubes, measuring approximately 150 to 200 nm on a side, prepared by a molten salt solid-state reaction method in the compositional range wherein $0.5\ensuremath{\le}x\ensuremath{\le}1$. Powder x-ray diffraction (XRD) and monochromatic synchrotron XRD studies indicate products of high purity, which undergo gradual, well-controlled structural transformations from rhombohedral to tetragonal structures with decreasing ``$x$.'' For all solid solution products, room-temperature magnetization studies exhibit hysteretic behavior with remnant magnetization values of ${M}_{\text{r}}\ensuremath{\ge}0.32\text{ }\text{emu}/\text{g}$, indicating that the latent magnetization locked within the toroidal spin structure of ${\text{BiFeO}}_{3}$ has been released. Room-temperature M\"ossbauer spectra show composition-dependent characteristics with decreasing magnetic hyperfine field values and increasing absorption linewidths due to a decrease in the magnetic exchange interaction strength with decreasing $x$. For the lowest $x=0.5$ composition studied, the M\"ossbauer spectra show paramagnetic behavior, indicating a N\'eel temperature for this composition below 300 K. However, room-temperature magnetization studies with applied fields of up to 50 kOe show hysteretic behavior for all compositions, including the $x=0.5$ composition, presumably due to field-induced ordering. Furthermore, hysteresis loops for all compositions exhibit smaller coercivities at 10 K than at 300 K, an observation that may suggest the presence of magnetoelectric coupling in these systems.

Ethernet based communication protocols have recently gained more importance. The IEEE 1588 standard is the most widely used synchronization algorithm for Ethernet based communication protocols. The IEEE 1588 standard uses the centralized synchronization method. In this case, the malfunction of a specific node that sends the master clock can affect the performance of synchronization of every node on the network. The low synchronization performance of the nodes can cause malfunctions of the synchronous control system. For this reason, we believe the distributed synchronization method is more suitable for the industrial communication protocols. Therefore, we suggest a distributed synchronization algorithm that combines the IEEE 1588 and the FlexRay synchronization algorithm.

Strontium titanosilicate (Sr2TiSi2O8) is the Sr-analogue of fresnoite (Ba2TiSi2O8). It may provide useful properties due to the unusual five-coordinate titanium in its structure. Sr2TiSi2O8 is also a possible oxide form for the immobilization of short-lived fission products in radioactive waste. Through β decay, strontium decays to yttrium and then to zirconium. Therefore, not only the stability of Sr-loaded waste forms but also that of a potential decay product series with charge-balance in a naturally occurring mineral or ceramic is of fundamental importance. To incorporate the reaction 3Sr2+=2Y3++vacancy in the fresnoite composition, Y-substituted Sr-analogues of fresnoite, (Sr2−xY2/3x)TiSi2O8 (x=0, 0.5, 0.75, 1, 1.25, and 1.5) were prepared by a high-temperature synthesis and were found to form glass upon cooling. The Y-end-member (Y1.33TiSi2O8, x=2) crystallized to a mixture of Y2TiSiO7, TiO2, and SiO2 upon quenching in air. The enthalpies of formation of Y-substituted Sr-fresnoite glasses were obtained from drop solution calorimetry in a molten lead borate (2PbO·B2O3) solvent at 702°C. The enthalpies of formation from constituent oxides were exothermic but become less so with increasing Y content. The enthalpy of vitrification of Sr2TiSi2O8 composition was measured to be 68.5 ± 6.2 kJ/mol. The thermodynamic stability of the Y-substituted Sr-analogue of crystalline fresnoite may become marginal with increasing yttrium content. Their ready glass formation, even in the absence of radiation, suggests that amorphous phases may dominate as the Sr- and Cs-containing waste forms decay.

Effects of the properties of support and the preparation condition on the characteristics of carbon-supported palladium catalysts were investigated. The characteristics included dispersion and distribution of metal and the catalytic activity on the liquid-phase hydrogenation of dinitrotoluene. Oxidation of carbon support appeared to increase the number of surface oxygen groups and to enhance dispersion of palladium. However, the catalytic activity did not improve in proportion to the dispersion. In carbon-metal salt slurry, nuclei formation and growth by ion exchange and/or reduction was considered to be the most important step in determining the final state of the catalysts prepared by the alkali hydrolysis method. The catalytic activity was found to be strongly dependent on metal location throughout the mesopore structure especially in the case of catalysts supported on highly porous activated carbon

The pore structure of the 40 wt% Ni/kieselguhr catalyst prepared by precipitation of nickel component from a 0.17 M nickel nitrate solution at 90°C changes when the precipitant, 1 M Na2CO3 solution, is added to the nickel nitrate solution over different periods. After precipitation for 22 hours, the catalyst experiences narrowing of the pore mouth which leads to appearance of new small pores. However, when the catalyst is prepared by precipitation for 2 hours, the small pores present in the kieselguhr support are blocked by the precipitate particles and only the large pores are remained in the catalyst. The catalyst containing relatively small pores exhibits low reaction rates and changes in the product selectivity in soybean-oil hydrogenation, due to the diffusional resistance of the reactants in the catalyst pores. The effect of the diffusional resistance is not observed with CO hydrogenation, benzene hydrogenation and n-hexane hydrogenolysis, where molecular sizes of the reactants are significantly smaller than the catalyst pores.

Otter populations are declining throughout the world and most otter species are considered endangered. Molecular methods are suitable tools for population genetic research on endangered species. In the present study, we analyzed the complete mitochondrial genome (mitogenome) sequence of the Eurasian otter Lutra lutra. The mitochondrial DNA sequence of the Eurasian otter is 16,505 bp in length and consists of 13 protein-coding genes, 22 tRNAs, 2 rRNAs, and a control region (CR). The CR sequence of otters from Europe and Asia showed nearly identical numbers and nucleotide sequences of minisatellites. Phylogenetic analysis of Mustelidae mitogenomes, including individual genes, revealed that Lutrinae and Mustelinae form a clade, and that L. lutra and Enhydra lutris are sister taxa within the Lutrinae. Phylogenetic analyses revealed that of the 13 mitochondrial protein-coding genes, ND5 is the most reliable marker for analysis of phylogenetic relationships within the Mustelidae.

We present an ideal host-guest concept for highly efficient phosphorescent OLEDs (PHOLEDs). Highly efficient PHOLEDs with an extremely low doping concentration of 1% are developed. The origin of such a low doping is revealed by energy transfer mechanism studies and ideal host-guest concept. Simple architectures for PHOLEDs are realized based on this ideal host guest concept. Organic bi-layered and triple-layered architectures for PHOLEDs with high efficiency are reported. Results reveal a practical way to fabricate the highly efficient simple structure devices for trouble-free manufacturing processes.

129 Xe NMR spectra of xenon gas adsorbed on amorphous carbons have been obtained under various pressures up to 1 atm at 296 K. The chemical shift thus obtained has been found to be a linear function with respect to the surface concentration of the adsorbed xenon. The value of the chemical shift extrapolated to zero concentration is clearly increased when acidic functional groups are present on the carbon surface, indicating that the 129 Xe NMR spectroscopy can be a sensitive probe for the characterization of the amorphous carbon

We present highly efficient red and green phosphorescent devices comprising only two organic layers. Novel host materials having good electron transporting and new narrow band-gap fluorescent characteristics lead to the fabrication of simplified high efficiency devices. The driving voltage value of 3.3 V to reach luminance of 1000 cd/m 2 is reported in simple bi-layer red and green phosphorescent OLEDs, respectively. The maximum current- and power-efficiency values of 38.30 cd/A and 46.60 lm/W are demonstrated in this green device. The current and power efficiencies of bi-layered red PHOLED are 9.38 cd/A and 11.72 lm/W. Results reveal a practical way to fabricate highly efficient truly bi-layer organic devices for trouble-free manufacturing processes.

The synthesis of single-crystalline, cubic perovskite KMnF3 and NH4MnF3 nanorods, and their rare-earth-ion-doped analogues with reproducible shapes and sizes, has been realized using a modified template-directed approach, report Stanislaus Wong and co-workers on p. 103. The properties of the nanorods and their as-doped counterparts suggest their practical incorporation into functional nanometer-scale devices with applications in a number of fields. The cover shows the crystal structure of perovskite fluorides overlaid on a SEM image of as-prepared KMnF3 nanorods with diameters measuring around 50 nm. The generalized green synthesis of single-crystalline KMnF3 and NH4MnF3 nanorods as well as of their rare-earth ion doped analogues, possessing reproducible shape and controllable size, has been achieved using a modified template-directed approach under ambient room-temperature conditions, with simple inorganic salts as functional precursors. Extensive characterization of the resulting nanorods has been performed using diffraction, electron microscopy, optical spectroscopy, as well as magnetic techniques. We have studied the antiferromagnetism of as-prepared ternary metal fluoride nanorods as well as the luminescence of their as-doped counterparts. Our collective data suggest the possibility of the incorporation of these high-quality, chemically pure materials into functional nanoscale devices with various potential applications that exploit the interesting optomagnetic properties of these systems.

We report novel bipolar host materials for high efficiency red and green phosphorescent OLEDs (PHOLEDs). Phenyl moieties were inserted in a 4,4'-N,N'-dicarbazolebipheyl (CBP) compound to provide much easier electron injection and to increase electron mobility. The efficiency increase and voltage reduction by this modification were observed in red and green PHOLEDs. At a given constant luminance of 1000 cd/m 2 , the power efficiency was enhanced at least by twenty percent in the general red and green PHOLED devices.

As a result of intensive research on polymer light-emitting diodes (PLEDs) for the last several years, the device performances have been remarkably improved. Recently, several researchers reported on a PLEDs with an interlayer between poly(3,4-ethylenedioxythiophene)-poly-(styrenesulfonate) (PEDOT:PSS) and an emissive polymer. It improved the device efficiency as well as the device lifetime. The role of the interlayer is to block the electron from back diffusion to PEDOT:PSS and/or to reduce luminescence quenching at the PEDOT:PSS interface. We studied the improvement of the PLED by inserting an octadecyltrichlorosilane (OTS) as the interlayer between PEDOT:PSS and the emissive layer. The OTS was treated on PEDOT:PSS through the self-assembled monolayer (SAM) process. It improved the device efficiency of the PLED from 3.86 to 4.76 cd/A, and increased the operation lifetime from 270 to 340 minute comparing the non-OTS treated PLED with the OTS treated PLED for 10 min. In blue PLED, inserting the OTS layer between blue polymer and PEDOT:PSS is promoted hole injection from an anode. Therefore, the device efficiency is improved, which appears to be due to the increase of balanced recombination as a result of the accumulated electrons near the interface between emissive layer and PEDOT:PSS.

BACnet(Building Automation and Control Networks) is a standard data communication protocol specifically designed for building automation and control systems, BACnet provides six options for data link layer protocols and these six data link layer options can be applied with various wired transmission media. Recently wireless technology prevails in automation area. ZigBee is an IEEE 802.15.4 based standard communication protocol for low-rate wireless personal area networks. In this study, we propose a BACnet over ZigBee model that adopts ZigBee communication channel as a wireless data link layer protocol in a BACnet-based communication network system. We also applied this model to an experimental model to evaluate the feasibility of proposed technology. The technology proposed in this paper can expand the BACnet application using the advantages of wired and wireless integrated network solution.

Environmentally friendly synthetic methodologies have gradually been implemented as viable techniques in the synthesis of a range of nanostructures. In this work, we focus on the application of green-chemistry principles to the synthesis of complex metal oxide and fluoride nanostructures. In particular, we describe advances in the use of the molten-salt synthetic methods, hydrothermal protocols, and template-directed techniques as environmentally sound, socially responsible, and cost-effective methodologies that allow us to generate nanomaterials without the need to sacrifice sample quality, purity, and crystallinity, while allowing control over size, shape, and morphology.

This study determined the sensitivity and specificity of parental overweight from self-reported height and weight to identify families with overweight school age children. A cross sectional study was conducted among 3059 parents and their children (1558 boys and 1501 girls) aged 7-12 years in five primary schools of Busan, Korea. BMI was calculated from parental reported height and weight and from children's measured height and weight. Parents were considered overweight when their BMI was25 kg/m2 (WHO, 2000). Children were considered overweight when their BMI was95th percentile (CDC, 2000). Prevalence of overweight was calculated and logistic regressions were performed. The sensitivity and specificity of parental overweight were calculated. A total of 26% (805/3059) parents were overweight. Of the families with one overweight parent, 15% (N = 109) had an overweight child. When both parents were overweight, 17% (N = 9) had an overweight child. After adjusting for child's age and gender, parental education, family income, and spouse's BMI as required, the odds of having an overweight child were 2.5 [1.8, 3.3] for one overweight parent, and 3.2 [1.4, 7.1] for both overweight parents. While the sensitivity of one overweight parent to identify families with overweight school age children was 44%, specificity was 75%. The presence of both overweight parents provided a 3% sensitivity and 98% specificity for the identification of an overweight school age child. Although parental overweight was obtained from self-reported weight and height in Busan (Korea), it is a practical indicator to identify families with an overweight school age child, it has poor sensitivity.

Digital communication networks have become a core technology in advanced building automation systems. BACnet (building automation and control networks) is a standard data communication protocol designed specifically for building automation and control systems. BACnet adopts master-slave/token-passing (MS/TP) protocol as one of its field level networks. In this study, we evaluate the performance of BACnet MS/TP protocol using experimental model. The network performance is investigated and evaluated in terms of token rotation time and service delay. Experimental results show that the performance of MS/TP network is heavily affected by the network configuration parameter called Nmax_info_frames

A fast sol−gel synthetic route for obtaining alumina aerogels has been developed by modifying the tranditional method under appropriately controlled conditions. The highly mesoporous alumina aerogel prepared by our new sol−gel synthesis method and CO2 supercritical drying had a surface area in excess of 700 m2/g and high thermal stability.

The fieldbus provides real-time communication among field devices in the manufacturing automation and process control systems. In this study, an experimental model of the Profibus-based manufacturing automation system is developed. The experimental model consists of two robots, two conveyor belts, NC machine, PLC, sensors and operator station. These machines are interconnected into the Profibus network and exchange their data through the services provided by FMS (Fieldbus Message Specification). The experimental model is used to measure the network-induced delay of variable and file data transmitted through FMS services. This study analyzes the network-induced delays at each sublayer of the Profibus protocol stack. The experimental results obtained from this study promote understanding the delay characteristics of the Profibus FMS.

Palladium has long been recognized as an effective catalyst for many organic reactions in the liquid phase, especially when supported by carbon. To evaluate the qualities of the different types of catalysts available on the market, it is necessary to characterize them by measuring the free metal surface area, that is, the dispersions. It is well known that, using largely empirical recipes, the dispersion of some metals can be measured by chemisorption methods. 6 refs., 3 figs., 1 tab.

연구배경: 세계보건기구(WHO)에서는 나트륨을 하루 2 g 미만으로 섭취할 것을 권하고 있다. 이 권장 기준과 비만과의 연관성을 평가하여, WHO 권장기준이 비만에 대한타당성을 알아보고자 한다. 방법: 2010년부터 2012년까지 시행한 제5기 국민건강영양조사을 이용하였으며, 혈액 검사, 만성질환, 생활습관, 영양관련 설문조사 등의 자료에 결측치가 없는 19세 이상성인 14,694명을 대상으로 하였다. 비만은 체질량지수 25 kg/m2 이상으로 정의하고, 나트륨 섭취량은 24시간 회상법을 이용하여 계산해서, 2 g 미만, 2-4 g, 4-6 g, 6-8 g, 8 g 이상 5개 군으로 나누었다. 나트륨 섭취량과 비만의 연관성은 로지스틱회귀분석을 사용하였다. 결과: 남성에서 교란 변수 보정 후에 2 g 미만 섭취군에비해 2-4 g, 4-6 g, 6-8 g, 8 g 이상 섭취군의 비만에 대한 교차비가 1.27 (95% 신뢰구간[95% CI], 0.97-1.67), 1.40 (95% CI, 1.07-1.85), 1.41 (95% CI, 1.05-1.89), 1.61 (95% CI, 1.19-2.18)로 나타났으며 섭취량이 높은 군일수록 비만이 증가하였다(P value for trend＝0.020). 여성은 2 g 미만섭취군에 비해 8 g 이성 섭취하는 군만 교차비가 1.28 (95% CI, 1.02-1.62)였으나, 나트륨 섭취량이 증가함에 따라 비만이 증가하는 경향은 없었다(P value for trend＝ 0.221). 결론: 본 연구를 통해 남성에서 나트륨 섭취량이 2 g 이상으로 증가하면, 비만의 위험도가 독립적으로 증가하는것을 알 수 있었다. 따라서 나트륨 섭취량을 2 g 미만으로낮추는 것이 비만 예방에 도움이 될 것으로 보인다.

A study of the influence of mesoporous SiO2 on the dehydrogenation of NaAlH4 and TiF3-doped NaAlH4 revealed that the amount of hydrogen evolved is 3.8 wt% for the pristine NaAlH4 and around 4.2 wt% for the TiF3-doped NaAlH4, but increases to 4.9-5.0 wt% once the samples are doped with mesoporous SiO2 in the temperature range of 100-350 °C. A favorable synergistic effect on the NaAlH4 dehydrogenation is achieved as mesoporous SiO2 is added as a codopant along with TiF3, which is associated with the nanosized pores and high specific surface area of mesoporous SiO2. The catalytic mechanism of mesoporous SiO2 is more physical than chemical relative to the catalytic mechanism of TiF3.

We have developed novel bipolar host materials for high efficiency green phosphorescent OLEDs (PHOLEDs). Phenyl moieties were inserted in a 9,9′-(biphenyl-4,4′-diyl)dicarbazole (CBP) compound to pr...

CO 2 reforming of methane was carried out over nickel-alumina aerogel catalysts prepared with various Ni loadings. Compared with alumina-supported Ni catalyst prepared by conventional impregnation method, nickel-alumina aerogel catalysts exhibited remarkably low coking rate due to highly dispersed metal particles. From TEM studies, it was observed that the metal particle size significantly influenced the formation of filamentous carbon. Addition of potassium to the nickel-alumina aerogel catalysts appeared to improve the stability of the catalyst at 923 K while the effect was not clear at higher temperatures.

Pb-substituted hydroxyapatites (Ca (10-x) Pb x (PO 4 ) 6 (OH)) 2 , x=0-10) prepared by coprecipitation method were studied as catalysts for oxidative coupling of methane using gas flow reactor in the temperature range of 675 to 800°C. They showed much higher activity for the production of C 2 compounds than those of unsubstituted hydroxyapatites. Especially, Ca 9.5 Pb 0.5 (PO 4 ) 6 (OH) 2 showed the highest activity among them, which revealed maximum C 2 yield of about 22%. As compared to the catalysts prepared by ion-exchange method, these catalysts had much higher activity and better thermal stability. Such high activity and stability of the catalysts could be confirmed by XPS, XRD, ICP, etc. to be resulted from the optimum amount of Pb substitution, uniformity of structure, and the maintenance of their own structure during the reaction.

The cavities in coordination boxes, cages, and capsules are attracting much attention because of their encapsulation, catalytic reaction, and stereoselective transformation properties. “Inorganic Tennis Ball” (“ITB”) was named to the supramolecule obtained from the self-assembly of Cu(BF4)2 and (dach)Pt(BETMP) (dach = trans-1,2-diaminocyclohexane and BETMP = bisethylthiomethylidenepropanedioate). The cavity and hydrophobic pocket in the ITB have shown recognition properties for anions and pyridine molecules. It is essential to modify the metal sites in order to induce novel magnetism, encapsulation or reaction properties from ITB. We have devoted efforts to find out other transition metals that can replace copper(II) in the ITB. We now report the synthesis and characterization of a new cobalt(II)-based ITB and its magnetic properties. BETMP is a multidentate ligand with two sulfur atoms and two carboxylate groups. A diamineplatinum(II) moiety, (dach)Pt(II), was reported to be coordinated to the ligand exclusively by two sulfur atoms while copper(II) ion, on the other hand, by carboxylate oxygens. To reveal the coordination property of cobalt(II) ion to the ligand, cobalt(II) sulfate and potassium sulfate was reacted with two equivalents of Ba[BETMP] in water. After stirring for 2 h, the precipitate (BaSO4) was removed by filtration, and recrystallization in methanol/ether of the crude product obtained by evaporation of the filtrate afforded the crystalline compound K2Co(BETMP)2(HOCH3)2 (1) (Figure 1). Two carboxylates and two methanols coordinate cobalt(II), where the distance from cobalt(II) to methanol oxygen is 2.165(4) A. Compound 1 was reacted with two equivalent (dach)Pt(NO3)2 in methanol. After removal of KNO3 by filtration, crystalline compound [[{(dach)Pt(BETMP)}2Co(OHCH3)]2(NO3)][NO3]3 (2·[NO3]3) was obtained by slow evaporation of the filtrate (Scheme 1). ESI-MS spectrum of the methanol solution of 2·[NO3]3 detected the ions of m/z = 784.7 and 1207.4 which corresponds to [2-(OHCH3)2] and [(2-(OHCH3)2)·NO3], respectively, unique ions proving the existence of the tennis ball structure in the solution. Figure 2 shows the crystal structure of of 2. Compound 2 is a dimer composed of two homo copies. Hydrogen bonding interactions between NH of one copy and carboxylate oxygens of the other (the distances of N...O range from 2.97 to 3.03 A) are important driving forces for the formation of the dimer. The close contacts between two sulfurs in different copies (these distances range from 3.62 to 3.75 A) seem to also contribute to the gathering of the two copies. A NO3− anion is centered at the cavity inside the dimer. The distance between Co(II) and methanol oxygen is 2.129(18) A. This distance, along with that of 1, is similar to those often observed in other cobalt complexes. Figure 3 shows the electron paramagnetic resonance (EPR) spectrum of the compound 2·[NO3]3 in frozen solution state. The broad EPR feature from 75 to 360 mT Figure 1. ORTEP drawing of the anionic part of 1. The molecule has inversion symmetry. Bond distances (A): Co(1)-O(1), 2.042(3); Co(1)-O(4), 2.076(3); Co(1)-O(5), 2.165(4).

Background The relationships of total and regional body fat percent with bone mineral density (BMD) in Korean adolescents were examined using the Fifth Korea National Health and Nutrition Examination Survey (KNHANES V-1), 2010. Methods Body fat percent at whole body (WBFP), trunk (TBFP), and extremities (both upper and lower extremities fat mass/body weight, EBFP), ratio of trunk fat mass to extremities fat mass (TEFR), and BMD at whole body, total femur, and lumbar spine were measured by dual energy X-ray absorptiometry in a population-based sample of 433 boys and 362 girls, aged 12 to 18 years. The analyses were conducted using linear regression analysis with complex sampling design. Results After adjusting for confounders such as age, height, weight, serum 25-(OH) vitamin D concentration, energy intake, calcium intake, physical activity, and menarche status for girls, WBFP, TBFP, and EBFP were inversely associated with whole and regional BMD in both sexes (P < 0.05). TEFR was positively associated with whole and regional BMD in boys after adjusting for confounders, while it was negatively associated in girls (P < 0.05). However, the associations were non-significant when bone mass-free lean mass was adjusted instead of bodyweight except for a positive association between TEFR and BMD in boys. Conclusion In Korean adolescents, total and regional body fat percent is not independently associated with BMD after adjusting for bone mass-free lean mass but higher fat in trunk as compared to extremities may be protective for BMD in boys.

ZSM-5 catalysts were prepared by conventional and direct heating hydrothermal crystallization methods. Silicalite-covered-ZSM-5 catalysts were also prepared in the presence of those ZSM-5 catalysts as seeds by the successive crystallization of silicalite outside the ZSM-5 cores. Crystalline silicalite which comprises outer portion of the silicalite-covered-ZSM-5 catalyst was identified by IR and confirmed by TG as well as γ-collidine TPD. Internal and external surface acid sites of the catalysts were characterized by ammonia and γ-collidine TPD analyses. Compared with the ZSM-5 catalysts prepared by the conventional method, those by the direct heating method exhibited higher activity for toluene disproportionation reaction. However, they suffered from lower p-selectivity and faster deactivation. When modified by covering with silicalite shell, both ZSM-5 (direct) and ZSM-5 (conventional) became less active but more p-selective and resistant to deactivation.

In this paper, we propose an efficient method to describe and save Jeongganbo score which has various structures and symbols by using XML (Extensible Markup Language). To do this, analysis of Jeongganbo`s structures, and classification of symbols for jeongganbo were preformed. Then, Jeongganbo DTD (Document Type Definition) was defined to describe Jeongganbo score in XML document. To verify the proposed method, we produced a Jeongganbo score XML file for real Jeongganbo score according to the proposed Jeongganbo DTD, and then evaluated the produced XML file by using Jeongganbo XML interpreter software which can interpret the Jeongganbo XML file and represent the Jeongganbo score.

Background: Depressive symptoms accompanied by chronic obstructive pulmonary disease (COPD) can be influenced by socioeconomic status, associated chronic diseases and the current smoking status. This study was conducted to assess factors that are associated with depressive symptoms accompanied by COPD, using the data obtained from the Korea National Health and Nutritional Survey (KNHANES) conducted in 2005 and 2008. Methods: From the third (2005) and the fourth (2008) KNHANES, 407 (0.9%) with physician-diagnosed COPD were selected. Of the 407 subjects, only 180 (0.4%) who reported having depressive symptoms were included in this study. The associations of depressive symptoms with socioeconomic status, associated chronic diseases and smoking status were investigated. Results: Of the total 180 subjects, 45 (25%) had depressive symptoms. There were 102 males (55%) and 78 females (45%) with a slight predilection for males. In multivariate analysis, significant predictors of depressive symptoms were dependent activities of daily living (odds ratio [OR], 2.42; 95% confidence interval [CI], 2.06 to 2.84) and association with number of chronic diseases (OR of one, two, and three, 1.40, 1.72, 2.60; 95% CI of one, two, and three, 1.20 to 1.63,1.41 to 2.10,1.99 to 3.39). Conclusion: This study provides the basis for managing COPD patients in a clinical setting by understanding the number and characteristics of COPD patients with depressive symptoms. The results of this study suggest that primary physicians should manage COPD patients with consideration of risk factors for depressive symptom.

Highly efficient red phosphorescent organic light-emitting devices (PHOLEDs) were fabricated using extremely low doping technology in a simple device configuration. They were developed by making use of the narrow-bandgap fluorescent host material bis(10-hydroxybenzo[h] quinolinato)beryllium complex (Bebq2) and red dopant tris(1-phenylisoquinoline)iridium (Ir(piq)3). Maximum current and power efficiencies of 11.60 cd/A and 13.02 lm/W, respectively, are demonstrated with an extremely low doping level of 1 wt%. These results reveal a practical way to make highly efficient PHOLEDs by reducing dopant self quenching.

We report highly efficient red phosphorescent organic light-emitting diodes with a triplet p-i-n single quantum well (QW) structure. This p-i-n single QW structure is realized using p-doped and n-doped wide band-gap hole and electron injection and transporting layers with narrow band-gap host and dopant materials. The maximum current and power efficiencies of 11.1 cd/A and 14.4 lm/W, respectively, are demonstrated by a good carrier confinement effect of QW. Very low driving voltage characteristics of 3.7 ∼ 3.9 V at 1000 cd/m2 are realized by almost no injection barrier with high conductivity configuration in our p-i-n structure.

Background: This study aimed to examine the factors related to eating behavior subscales and change of eating behavior subscales among obese patients received weight reduction management. Methods: Eating behavior subscales (restrained eating, emotional eating, and external eating) were assessed using the Korean version of Dutch Eating Behavior Questionnaire in 76 obese female patients at obesity clinic and 83 female visitors at health promotion center. Fifty nine patients received weight reduction management and completed followup survey after 2-3 months. Demographics, physical activity, health behaviors, diet experience, BMI, and weight change were assessed. Results: The score of restrained eating was significantly higher in obese patients compared to controls, while scores of other subscales were not different between the two groups. Diet experience, score of emotional eating, and BMI explained 15% of variance of restrained eating score after adjustment for covariates. Likewise, increase of restrained and external eating scores and younger age explained 27% of variance of emotional eating score. External eating score was associated with increase in emotional eating score, higher education, regular exercise, and frequent overeating (R 2 = 30%). Among obese patients, the follow-up score of restrained eating was significantly higher compared to that score at baseline, while the scores of emotional and external eating were not significantly changed. After adjustment for covariates, only irregular eating habit was associated with the change of restrained eating score. Conclusion: Restrained eating score was associated with BMI regardless of subjects group, while, among obese patients, the change of restrained eating score was associated with frequent irregular eating habit.

We report the direct determination of surface enthalpies for nanophase TiO2 anatase with different morphologies derived from drop solution calorimetry in a molten sodium molybdate (3Na2Oŀ4MoO3) solvent at 702 °C. The energetics of surface hydration has been measured using a Calvet microcalorimeter coupled with a gas dosing system. The surface enthalpies of hydrated surfaces for anatase TiO2 nanoparticles, nanowires and sea-urchin-like assemblies are 0.51 ± 0.05, 1.07 ± 0.28, and 1.29 ± 0.16 J m−2, respectively, whereas those of anhydrous surfaces are 0.74 ± 0.04, 1.24 ± 0.28, and 1.41 ± 0.16 J m−2, respectively. The trend in TiO2, which shows higher surface enthalpies for more complex nanostructures, is consistent with that reported in ZnO. The shape-dependent surface enthalpy at the nanoscale level is discussed in terms of exposed surface structures. The enthalpies of hydration appear to be similar for all morphologies.

We demonstrate the multiple quantum well (MQW) structures with the charge control layers (CCLs) to produce highly efficient red phosphorescent organic light-emitting devices (OLEDs). Various triplet quantum well devices from a single to five quantum wells are realized using wide band-gap hole and electron transporting layers, narrow band-gap host and dopant materials, and CCLs. Triplet energies in such MQW devices are confined at the emitting layers. The maximum external quantum efficiency of 14.8% with a two quantum well device structure is obtained. The described MQW device concept has been proposed to be very useful to future OLED display and lighting applications.

We present simple p-i-n structures with double-emitting and mixed-emitting layers for highly efficient phosphorescent green devices. Using a wide band-gap hole transporting material of 4,4′4″-tris(N-carbazolyl)-triphenylamine and a wide band-gap electron transporting material of bis[2-(2-hydroxyphenyl)-pyridine]beryllium, the bilayered p-i-n structure with no heterointerface barriers has been realized. A very low onset voltage value of 2.4 V corresponding to the energy of 2.4 eV of green electroluminescence, which is close to the photon energy of dopant emitting molecules (2.3–2.4 eV), is achieved in this simple p-i-n device configuration. Maximum current- and power-efficiency values of 53.3 cd/A and 61.4 lm/W and low rolloff of current efficiency (6%) are demonstrated in the simple p-i-n green phosphorescent devices, promising for the practical and economical high brightness applications.

Using a narrow band-gap fluorescent host material with a phosphorescent red dopant, highly efficient red phosphorescent OLEDs (PHOLEDs) exhibiting an ideal external quantum efficiency with a doping concentration of 1% were developed. The origin of such a low doping is revealed by the ideal Dexter doping condition study for efficient energy transfer in PHOLEDs. Besides this cause, the strong fluorescent host materials function very well in phosphorescent OLEDs. Singlet excitons generated by fluorescent host materials in phosphorescent OLEDs can produce dopant triplet excitons via the efficient Forster energy transfer mechanism.

Background: It is important to evaluate the functional ability of the elderly for optimal care. This study was conducted to identify factors associated with dependence for activities of daily living (ADL) and instrumental activities of daily living (IADL) in elderly adults in Korea. Methods: A cross-sectional study of data from the third Korea National Health and Nutrition Examination Survey (KNHANES III) 2005 was undertaken. The sample consisted of 3,656 participants, 65 years of age or older. Multifactorial regression analysis was used to identify associations between ADL and IADL dependence and sociodemographics, lifestyle, and health history. Results: Among the 629 (17.2%) ADL-dependent and signifi cantly and independently associated factors were age, lower education level, health assistance or no-insurance, stroke, urinary incontinence, diabetes, arthritis, and lung cancer. Among the 1,674 (55.7%) IADL-dependent and significantly and independently associated factors were age, lower education level, single or widowed, male, stroke, arthritis, glaucoma and/or cataract. Conclusion: Functional dependence in older adults was directly related to aging and had multiple determinants. Awareness of these determinants should help design health programs that can identify individuals who are at high risk of losing their independence, and implement interventions for slowing or reversing the process.

Background: After the referral system had been established, a tendency of patients who prefer to consult themselves to a specialist with 'self requested referral' is increasing in university hospital family medicine clinics. This study was conducted to know which factors of patients who for the fi rst time visited university hospital family medicine clinic to require medical request for 'self requested referral' to a specialist infl uence 'self requested referral' tendency. Methods: Among 905 patients, 647 agreed to the questionnaire were included in this study. We divided the patients in two, the 'self requested referral' group and the 'general patients' group that does not. Patients completed a four-item, selfadministered questionnaire. Results: 'Self requested referral' group tended to have no experience in family medicine and tended to be negative about the need for family medicine (P < 0.001) The factors that have effect on 'self requested referral' are age, occupation, education, experience of family medicine, and recognition degree of necessity of family medicine. Patients in 20-39 of age, who were white colored, higher education had higher tendency of 'self requested referral' and patients who had no experience in family medicine and lower degree of recognition about the necessity of family medicine had higher tendency of 'self-referral'. Conclusion: It is necessary to fi nd ways to increase satisfaction of patients who have factors that have effect on their 'self requested referral' tendency such as age, occupation, education, experience of family medicine, and degree of recognition about the necessity of family medicine.

We have developed a low cost AM backplane using non-laser polycrystalline silicon (poly-Si) having inverse staggered TFT. The thin-film transistors (TFTs) have a center-offset gated structure to reduce the leakage current without scarifying the on-currents. A center-offset length of the TFTs has 3 μm for both switching and driving TFTs. Finally, we have made a 2.2 inch QQVGA (160 × 120) active-matrix organic light emitting diode (AMOLED) display with conventional 2T 1C pixel circuits.