Characteristics and composition of atmospheric aerosols in Phimai, central Thailand during BASE-ASIA

Li, C.,Tsay, S.C.,Hsu, N.C.,Kim, J.Y.,Howell, S.G.,Huebert, B.J.,Ji, Q.,Jeong, M.J.,Wang, S.H.,Hansell, R.A.,Bell, S.W. Pergamon Press ; Elsevier [distribution] 2013 Atmospheric environment Vol.78 No.-

Comprehensive measurements of atmospheric aerosols were made in Phimai, central Thailand (15.183<SUP>o</SUP>N, 102.565<SUP>o</SUP>E, elevation: 206 m) during the BASE-ASIA field experiment from late February to early May in 2006. The observed aerosol loading was sizable for this rural site (mean aerosol scattering: 108 +/- 64 Mm<SUP>-1</SUP>; absorption: 15 +/- 8 Mm<SUP>-1</SUP>; PM<SUB>10</SUB> concentration: 33 +/- 17 μg m<SUP>-3</SUP>), and dominated by submicron particles. Major aerosol compounds included carbonaceous (OC: 9.5 +/- 3.6 μg m<SUP>-3</SUP>; EC: 2.0 +/- 2.3 μg m<SUP>-3</SUP>) and secondary species (SO<SUB>4</SUB><SUP>2-</SUP>: 6.4 +/- 3.7 μg m<SUP>-3</SUP>, NH<SUB>4</SUB><SUP>+</SUP>: 2.2 +/- 1.3 μg m<SUP>-3</SUP>). While the site was seldom under the direct influence of large forest fires to its north, agricultural fires were ubiquitous during the experiment, as suggested by the substantial concentration of K<SUP>+</SUP> (0.56 +/- 0.33 μg m<SUP>-3</SUP>). Besides biomass burning, aerosols in Phimai during the experiment were also strongly influenced by industrial and vehicular emissions from the Bangkok metropolitan region and long-range transport from southern China. High humidity played an important role in determining the aerosol composition and properties in the region. Sulfate was primarily formed via aqueous phase reactions, and hygroscopic growth could enhance the aerosol light scattering by up to 60%, at the typical morning RH level of 85%. The aerosol single scattering albedo demonstrated distinct diurnal variation, ranging from 0.86 +/- 0.04 in the evening to 0.92 +/- 0.02 in the morning. This experiment marks the first time such comprehensive characterization of aerosols was made for rural central Thailand. Our results indicate that aerosol pollution has developed into a regional problem for northern Indochina, and may become more severe as the region's population and economy continue to grow.

수험생활 중 경주 및 포항 지진 경험

김선주,김유영,김은주,박솔민,배지윤,이민영,이유진,정재원,Li Keying,Wuyingjinzhu,신수진,도지영 이화여자대학교 간호과학대학 2019 이화간호학회지 Vol.- No.53

Purpose: The purpose of this study was to understand the experiences of Gyeongju and Pohang earthquakes during the examinees’ life. Methods: This study applied Colaizzis’s Phenomenological method. The Data was collected through in-depth interviews with a total 8 students of university in Seoul. Results: On the analysis of the interviews, their experience can be expressed as ‘Feeling embarrassed and frightened by earthquakes’, ‘Reduced susceptibility to earthquake hazards due to heavy exam pressure’, ‘Increased exam stress due to earthquake’, ‘Feeling the inadequacy of examinees' earthquake related safety measures in retrospect’. Conclusion: This study was meaningful in deeply understanding of their experiences and revealing that the examinees were more focused on studying rather than actively coping with the disaster. Furthermore, it reconsider the social climate surrounding college admission exams. This study meaningfully discovered that examinees could not stably prepare for both the exam and the earthquake evacuation procedures due to the timing of the earthquake in relation to their upcoming college admission test. Therefore, this study highlighted the examinees’ difficulties due to the earthquakes and increased the necessity of acute phase nursing intervention in relation to the seismic safety education system.

Rational design of common transition metal-nitrogen-carbon catalysts for oxygen reduction reaction in fuel cells

Zheng, Yongping,Yang, Dae-Soo,Kweun, Joshua M.,Li, Chenzhe,Tan, Kui,Kong, Fantai,Liang, Chaoping,Chabal, Yves J.,Kim, Yoon Young,Cho, Maenghyo,Yu, Jong-Sung,Cho, Kyeongjae Elsevier 2016 Nano energy Vol.30 No.-

<P><B>Abstract</B></P> <P>Bio-inspired non-precious-metal catalysts based on iron and cobalt porphyrins are promising alternatives to replace costly platinum-based catalysts for oxygen reduction reaction (ORR) in fuel cells. However, the exact nature of the active sites is still not clearly understood, and further optimization design is needed for practical applications. Here, we report a rational catalyst design process by combining density functional theory (DFT) calculations and experimental validations. Two sets of square-planar (MN<SUB>x</SUB>C<SUB>4−x</SUB>) and square-pyramid (MN<SUB>x</SUB>C<SUB>5−x</SUB>) active centers (M=Mn, Fe, Co, Ni) incorporated in graphene were examined using DFT. Fe-N<SUB>5</SUB> and Co-N<SUB>4</SUB> sites were identified theoretically to have the best performance in fuel cells, while Ni-N<SUB>x</SUB>C<SUB>4−x</SUB> sites catalyze the most H<SUB>2</SUB>O<SUB>2</SUB> byproduct. Graphene samples with well-dispersed incorporations of metals were synthesized, and the following electrochemical measurements show an excellent agreement with the theoretical predictions, indicating that a successful design framework and systematic understanding toward the catalytic nature of these materials are established.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Graphene based catalysts design for ORR is demonstrated by combining experiments and modellings. </LI> <LI> Iron porphyrin like active site is unraveled to be five nitrogen coordinated as FeN<SUB>5</SUB>. </LI> <LI> Cobalt porphyrin like active site is shown to be four nitrogen coordinated as CoN<SUB>4</SUB>. </LI> <LI> Nickel porphyrin like catalyst is potentially used for catalytic synthesis of H<SUB>2</SUB>O<SUB>2</SUB>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

하이브리드 다층 인쇄회로기판의 굽힘 강도 개선에 관한 해석 및 실험적 연구

Le Li,김상목(S.M. Kim),송승호(S.H. Song),구태완(T.W. Ku),송우진(W.J. Song),김정(J. Kim),강범수(B.S. Kang) 한국정밀공학회 2007 한국정밀공학회 학술발표대회 논문집 Vol.2007 No.11월

Fungal diversity notes 253–366: taxonomic and phylogenetic contributions to fungal taxa

Li, G. J.,Hyde, K. D.,Zhao, R. L.,Hongsanan, S.,Abdel-Aziz, F. A.,Abdel-Wahab, M. A.,Alvarado, P.,Alves-Silva, G.,Ammirati, J. F.,Ariyawansa, H. A. Springer Science and Business Media 2016 FUNGAL DIVERSITY Vol.78 No.1

<P>Notes on 113 fungal taxa are compiled in this paper, including 11 new genera, 89 new species, one new subspecies, three new combinations and seven reference specimens. A wide geographic and taxonomic range of fungal taxa are detailed. In the Ascomycota the new genera Angustospora (Testudinaceae), Camporesia (Xylariaceae), Clematidis, Crassiparies (Pleosporales genera incertae sedis), Farasanispora, Longiostiolum (Pleosporales genera incertae sedis), Multilocularia (Parabambusicolaceae), Neophaeocryptopus (Dothideaceae), Parameliola (Pleosporales genera incertae sedis), and Towyspora (Lentitheciaceae) are introduced. Newly introduced species are Angustospora nilensis, Aniptodera aquibella, Annulohypoxylon albidiscum, Astrocystis thailandica, Camporesia sambuci, Clematidis italica, Colletotrichum menispermi, C. quinquefoliae, Comoclathris pimpinellae, Crassiparies quadrisporus, Cytospora salicicola, Diatrype thailandica, Dothiorella rhamni, Durotheca macrostroma, Farasanispora avicenniae, Halorosellinia rhizophorae, Humicola koreana, Hypoxylon lilloi, Kirschsteiniothelia tectonae, Lindgomyces okinawaensis, Longiostiolum tectonae, Lophiostoma pseudoarmatisporum, Moelleriella phukhiaoensis, M. pongdueatensis, Mucoharknessia anthoxanthi, Multilocularia bambusae, Multiseptospora thysanolaenae, Neophaeocryptopus cytisi, Ocellularia arachchigei, O. ratnapurensis, Ochronectria thailandica, Ophiocordyceps karstii, Parameliola acaciae, P. dimocarpi, Parastagonospora cumpignensis, Pseudodidymosphaeria phlei, Polyplosphaeria thailandica, Pseudolachnella brevifusiformis, Psiloglonium macrosporum, Rhabdodiscus albodenticulatus, Rosellinia chiangmaiensis, Saccothecium rubi, Seimatosporium pseudocornii, S. pseudorosae, Sigarispora ononidis and Towyspora aestuari. New combinations are provided for Eutiarosporella dactylidis (sexual morph described and illustrated) and Pseudocamarosporium pini. Descriptions, illustrations and/or reference specimens are designated for Aposphaeria corallinolutea, Cryptovalsa ampelina, Dothiorella vidmadera, Ophiocordyceps formosana, Petrakia echinata, Phragmoporthe conformis and Pseudocamarosporium pini. The new species of Basidiomycota are Agaricus coccyginus, A. luteofibrillosus, Amanita atrobrunnea, A. digitosa, A. gleocystidiosa, A. pyriformis, A. strobilipes, Bondarzewia tibetica, Cortinarius albosericeus, C. badioflavidus, C. dentigratus, C. duboisensis, C. fragrantissimus, C. roseobasilis, C. vinaceobrunneus, C. vinaceogrisescens, C. wahkiacus, Cyanoboletus hymenoglutinosus, Fomitiporia atlantica, F. subtilissima, Ganoderma wuzhishanensis, Inonotus shoreicola, Lactifluus armeniacus, L. ramipilosus, Leccinum indoaurantiacum, Musumecia alpina, M. sardoa, Russula amethystina subp. tengii and R. wangii are introduced. Descriptions, illustrations, notes and / or reference specimens are designated for Clarkeinda trachodes, Dentocorticium ussuricum, Galzinia longibasidia, Lentinus stuppeus and Leptocorticium tenellum. The other new genera, species new combinations are Anaeromyces robustus, Neocallimastix californiae and Piromyces finnis from Neocallimastigomycota, Phytophthora estuarina, P. rhizophorae, Salispina, S. intermedia, S. lobata and S. spinosa from Oomycota, and Absidia stercoraria, Gongronella orasabula, Mortierella calciphila, Mucor caatinguensis, M. koreanus, M. merdicola and Rhizopus koreanus in Zygomycota.</P>

Highly Sensitive and Selective Detection of Dopamine at Poly(chromotrope 2B)-Modified Glassy Carbon Electrode in the Presence of Uric Acid and Ascorbic Acid

Li, X.B.,Rahman, Md.M.,Xu, G.R.,Lee, J.J. Pergamon Press 2015 ELECTROCHIMICA ACTA Vol.173 No.-

A highly sensitive and selective electrochemical method based on a poly(chromotrope 2B)-modified anodized glassy carbon electrode (PCHAGCE) was developed for the determination of dopamine (DA) in the presence of uric acid (UA) and ascorbic acid (AA). The PCHAGCE sensor exhibited excellent electron-mediating behavior towards the oxidation of DA in 0.1M phosphate buffer solution (PBS) (pH7.0). It was found that the electrocatalytic activity was significantly dependent on the charge status and molecular structure of the target molecules. Differential pulse voltammetry (DPV) measurements revealed oxidation signals for DA, UA, and AA that were well-resolved into three distinct peaks with AA-DA, DA-UA, and AA-UA peak potential separations (ΔE<SUB>p</SUB>) of 172, 132, and 304mV, respectively. A detection limit of 0.04+/-0.001μM (S/N=3) and a quantification limit (S/N=10) of 0.149+/-0.03μM were obtained for DA sensing in a linear range of 1 to 40μM in PBS (pH7.0) with a very high sensitivity of 1.522+/-0.032μA.μM<SUP>-1</SUP>. The DA concentrations in human urine samples were also successfully determined with recoveries of 94.0-98.0%. This approach provides a simple, easy, sensitive, and selective method to detect DA in the presence of AA and UA.

The PPARα activator fenofibrate inhibits voltage-dependent K⁺ channels in rabbit coronary arterial smooth muscle cells

Li, H.,Shin, S.E.,Seo, M.S.,An, J.R.,Jung, W.K.,Ha, K.S.,Han, E.T.,Hong, S.H.,Bang, H.,Bae, Y.M.,Firth, A.L.,Choi, I.W.,Park, W.S. North-Holland 2017 European journal of pharmacology Vol.812 No.-

<P>We examined the effects of the PPAR alpha activator fenofibrate on voltage-dependent K+ (Kv) channels using a patch clamp technique in native rabbit coronary arterial smooth muscle cells. Kv current was inhibited by application of fenofibrate in a concentration-dependent manner, with an apparent IC50 value of 6.39 +/- 0.53 mu M and a slope value (Hill coefficient) of 1.63 +/- 0.10. Fenofibrate accelerated the decay rate of Kv channel inactivation. The rate constants of association and dissociation for fenofibrate were 0.81 +/- 0.05 mu M-1 s(-1) and 4.70 +/- 0.47 s(-1), respectively. Although fenofibrate did not affect the steady-state activation curves, fenofibrate shifted the inactivation curves toward a more negative potential. Application of train pulses (1 or 2 Hz) progressively increased the fenofibrate-induced inhibition of the Kv channel, and the recovery time constant from inactivation was increased in the presence of fenofibrate, which suggested that the inhibitory effect of fenofibrate is use-dependent. Another PPAR alpha activator, bezafibrate and PPARa inhibitor, GW 6471, did not affect the Kv current and also did not change the inhibitory effect of fenofibrate on the Kv current. From these results, we suggest that fenofibrate inhibited Kv current in a state-, time-, and use-dependent manner, completely independent of PPAR alpha activation.</P>

Using TiO₂ Mesoflower Interlayer in Tubular Porous Titanium Membranes for Enhanced Electrocatalytic Filtration

Li, X.,Liu, G.,Shi, M.,Li, J.,Li, J.,Guo, C.,Lee, J.K.,Zheng, J. Pergamon Press 2016 ELECTROCHIMICA ACTA Vol.218 No.-

The current study focuses on synthesis and characterization of novel functionalized anodic membranes for wastewater treatment. This membrane was prepared by first constructing a TiO<SUB>2</SUB> mesoflower interlayer on a tubular porous titanium membrane and subsequently coating an antimony-doped tin oxide catalytic layer. Physical and electrochemical characterizations of the membranes were evaluated. With TiO<SUB>2</SUB> mesoflower, the membrane anode obtained a higher oxygen evolution potential, 2.22V (vs saturated calomel electrode), relative roughness factor (701.7), and electrochemical porosity (99.23%) than membrane anodes without TiO<SUB>2</SUB> mesoflower. The prepared membrane anode also achieved a low charge-transfer (0.11Ω) and mass-transfer resistance (0.21Ω) in filtration mode. The unique features were found linked to its 3-D porous and open structure, and formation of a Ti<SUB>0.2</SUB>Sn<SUB>0.8</SUB>O<SUB>2</SUB> sosoloid that had a high surface oxygen (O<SUB>ad</SUB>) content. The electrocatalytic filtration performance of this membrane was also tested using methyl orange as a model organic pollutant. At a current density of 15mAcm<SUP>-2</SUP>, the membrane achieved a higher 71.0% removal of methyl orange than 58.0% for the membrane without TiO<SUB>2</SUB> mesoflower. At a 58.0% removal of methyl orange, the membrane consumed a much lower energy of 0.20 kWh m<SUP>-3</SUP> than 5.88 kWh m<SUP>-3</SUP> for membrane anodes without TiO<SUB>2</SUB> mesoflower. The synthesized membrane electrode filter shows promise for future applications aimed to remove organic pollutants from wastewater.

Magnetic Study of Heavily Mn-doped CuO Thin Films

L. Li,B. Lv,J. Z. Cai,W. Q. Zou,X. S. Wu,F. M. Zhang 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.62 No.10

Cu0.7Mn0.3O films were deposited by Plasma Enhanced Chemical Vapor Deposition and annealed in different atmospheres. The XRD diffraction results indicate that samples annealed in air and N2 both show pure CuO phases, while the film annealed in O2 has a secondary phase CuMn2O4. The content of Mn was confirmed by Energy dispersive X-ray spectroscopy. The M-T and M-H curves show that the average magnetic moment of the films prepared in O2 is larger than those prepared in air and in N2 atmosphere. Ferromagnetic segments Mn-O-Cu-O-Mn can be used to understand the ferromagnetism of CuO under heavily Mn-doping. And the magnetic moment per Mn ions calculated on the base of this chain model is consistent with the experimental result.

POLARIMETRY OF DG TAU AT 350 μm

Krejny, M.,Matthews, T. G.,Novak, G.,Cho, J.,Li, H.,Shinnaga, H.,Vaillancourt, J. E. IOP Publishing 2009 The Astrophysical journal Vol.705 No.1

<P>We present the first 350 mu m polarization measurement for the disk of the T Tauri star (TTS) DG Tau. The data were obtained using the SHARP polarimeter at the Caltech Submillimeter Observatory. We measured normalized Stokes parameters q = -0.0086 +/- 0.0060 and u = -0.0012 +/- 0.0061, which gives a 2 sigma upper limit for the percent polarization of 1.7%. We obtain information about the polarization spectrum by comparing our 350 mu m measurement with an 850 mu m polarization detection previously published for this source. Comparing the two measurements in Stokes space ( not in percent polarization) shows that the two data points are not consistent, i.e., either the degree of polarization or the angle of polarization (or both) must change significantly as one moves from 850 mu m to 350 mu m. This conclusion concerning the polarization spectrum disagrees with the predictions of a recent model for TTS disk polarization. We show that this discrepancy can be explained by optical depth effects. Specifically, we demonstrate that if one were to add more mass to the model disk, one would expect to obtain a model polarization spectrum in which the polarization degree falls sharply with increasing frequency, consistent with the observations at the two wavelengths. We suggest that multiwavelength polarimetry of TTS disk emission may provide a promising method for probing the opacity of TTS disks.</P>