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Science Bulletin 2017年第13期62卷 943-949页

作者： Hee Jin Kim Bibi Ruqia Mi Sung Kang Su Bin Lim Ran Choi Ki Min nam Won seok seo Gaehang Lee Sang-Il Choi Department of Chemistry and Green-Nano Materials Research Center Kyungpook National University Department of Chemistry KAIST Department of Chemistry Mokpo National University Department of Chemistry Sogang University Korea Basic Science Institute(KBSI) and University of Science and Technology

Synthesis of shape-controlled Pt nanocrystals is substantial and important for enhancing chemical and electrochemical ***,the removal of capping agents,shape-controlling chemicals,on Pt surfaces is essential prior to conducting the catalytic *** we report a facile one-pot synthesis of Pt nanocubes directly grown on carbon supports(Pt nanocubes/C) with modulating the kinetic reaction factors for shaping the nanocrystals,but without adding any capping agents for preserving the clean Pt ***-dispersed Pt nanocubes/C shows enhanced activity and long-term stability toward methanol oxidation reaction compared to the commercial Pt/C catalyst.

关键词： Platinum Nanocube Shape-control Kinetic product Methanol oxidation

Facile synthesis of fully ordered L10-FePt nanoparticles with controlled Pt-shell thicknesses for electrocatalysis

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Nano Research 2017年第8期10卷 2866-2880页

作者： Yonghoon Hong Hee Jin Kim Daehee Yang Gaehang Lee Ki Min nam Myung-Hwa Jung Young-Min Kim Sang-II Choi Won seok seo Department of Chemistry Sogang University Seou104107 Republic of Korea Department of Chemistry and Green-Nano Materials Research Center Kyungpook National University Daegu 41566 Repubfic of Korea Korea Basic Science Institute and University of Science and Technology Daejeon 34133 Republic of Korea Department of Chemistry Mokpo National University Jeonnam 58554 Republic of Korea Department of Physics Sogang University Seoul 04107 Republic of Korea Center for Integrated Nanostructure Physics Institute for Basic Science (IBS) Suwon 16419 Repubfic of Korea Department of Energy Science Sungkyunkwan University (SKKU) Suwon 16419 Republic of Korea

We report a simple one-step approach for the synthesis of -4 nm uniform and fully L10-ordered face-centered tetragonal （fct） FePt nanoparticles （NPs） embedded in -60 nm MCM-41 （fct-FePt NPs@MCM-41）. We controlled the Pt-shell thickness of the fct-FePt NPs by treating the fct-FePt NPs@MCM-41 with acetic acid （HOAc） or hydrochloric acid （HC1） under sonicafion, thereby etching the surface Fe atoms of the NPs. The fct-FePt NPs deposited onto the carbon support （fct-FePt NP/C） were prepared by mixing the fct-FePt NPs@MCM-41 with carbon and subsequently removing the MCM-41 using NaOH. We also developed a facile method to synthesize acid-treated fct-FePt NP/C by using a HF solution for simultaneous surface-Fe etching and MCM-41 removal. We studied the effects of both surface-Fe etching and Pt-shell thickness on the electrocatalytic properties of fct-FePt NPs for the methanol oxidation reaction （MOR）. Compared with the non-treated fct-FePt NP/C catalyst, the HOAc-treated and HCl-treated catalysts exhibit up to 34% larger electrochemically active surface areas （ECASAs）; in addition, the HCl-treated fct-FePt NP （with -1.0 nm Pt shell）/C catalyst exhibits the highest specific activity. The HF-treated fct-FePt NP/C exhibits an ECASA almost 2 times larger than those of the other acid-treated fct-FePt NP/C catalysts and shows the highest mass activity （1,435 mA·mgPt^-1, 2.3 times higher than that of the commercial Pt/C catalyst） and stability among the catalysts tested. Our findings demonstrate that the surface-Fe etching for the generation of the Pt shell on fct-FePt NPs and the Pt-shell thickness can be factors for optimizing the electrocatalysis of the MOR.

关键词： FePt face centered tetragonal bimetallic methanol oxidation reaction electrocatalysts

Effects of Melandrium firmum methanolic extract on testosterone-induced benign prostatic hyperplasia in Wistar rats

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Asian Journal of Andrology 2012年第2期14卷 320-324页

作者： Mee-Young Lee In-Sik Shin Chang-seob seo nam-Hun Lee Hye-Kyung Ha Jong-Keun Son Hyeun-Kyoo Shin Herbal Medicine EBM Research Center Korea institute of Oriental MedicineExporo 483Yusung-guDaejeon 305-811Koreaand Coilege of Pharmacy Yeungnam UniversityGyonsan 712-749Korea

Benign prostatic hyperplasia （BPH） is an age-related disease of unknown aetiology characterized by prostatic enlargement coincident with distinct alterations in tissue histomorphology. Instead of therapeutic agents that can cause severe side effects, plant extracts are frequently used to treat BPH. In this study, we investigated whether the Melandrium firmum methanolic extract （MFME） improves BPH, using the testosterone propionate （TP）-induced BPH rat model. Castration was performed via the scrotal route under sodium pentobarbital anaesthesia. BPH in castrated rats was generated via daily subcutaneous injections of TP （3 mg kg-1） dissolved in corn oil, for 4 weeks. MFME was administered daily by oral garage at a dose of 200 mg kg-1 for 4 weeks, along with the TP injections. The control group received injections of corn oil subcutaneously. At the scheduled termination of the experiment, all rats were killed and their prostates weighed; the relative prostate weight （prostate/body weight ratio） was calculated, and histomorphological changes in the prostate were examined. Additionally, we measured the levels of testosterone and dihydrotestosterone （DHT） in the serum and the prostate. Experimentally induced BPH led to marked decreases in the relative prostate weight and the DHT levels in the serum and the prostate. Histologically, BPH was evident in the ventral lobe of the prostate, and MFME treatment suppressed the severity of the lesions. These results indicate that MFME effectively inhibits the development of BPH induced by testosterone in a rat model. Further studies will be needed to identify the compound（s） responsibility for inducing the protective effect against BPH and determine its mechanism of action,

关键词： benign prostatic hyperplasia dihydrotestosterone Melandrium firmum (S. et Z.)RoHRB prostate testosterone

Synthesis of Ni-CeO_2 catalyst for the partial oxidation of methane using RF thermal plasma

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Chinese Journal of Catalysis 2016年第5期37卷 743-749页

作者： M.Y.Lee J.S.nam J.H.seo 韩国全北国立大学应用等离子体工程系韩国全北国立大学量子系统工程系

Ni‐CeO2 catalysts with a nickel content of 50 mol% were prepared using RF thermal plasma, and their catalytic activities for methane partial oxidation were characterized. For the synthesis of Ni‐CeO2 catalysts, a precursor containing Ni（～5‐μm diameter） and CeO2（～200‐nm diameter）powders were heated simultaneously using an RF plasma at a power level of ～52 kVA and a powder feeding rate of ～120 g/h. From the X‐ray diffraction data and transmission electron microscopy images, the precursor formed into high crystalline CeO2 supports with nanosized Ni particles（ 50‐nm diameter） on their surfaces. The catalytic performance was evaluated under atmospheric pressure at 500 °C and a CH4：O2 molar ratio of 2：1 with Ar diluent. Although the Ni content was high（～50 mol%）, the experimental results reveal a methane conversion rate of 70%, selectivities of CO and H2 greater than 90% and slight carbon coking during an on‐stream test at 550 °C for 24 ***, at 750 °C, the on‐stream test revealed the formation of filament‐like carbons with an increased methane conversion rate over 90%.

关键词： RF thermal plasma Methane Partial oxidation Nickel catalyst Ceria Carbon deposition

Intensive-visible-light-responsive ANbO_(2)N(A = Sr, Ba) synthesized from layered perovskite A_(5)Nb_(4)O_(15) for enhanced photoelectrochemical water splitting

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Journal of Energy Chemistry 2022年第5期31卷 529-537页

作者： Sukanya Ramaraj Jeongsuk seo Departmentof Chemistry.College of Natural Sciences Chonnam National University.77 Yongbong-ro Buk-gu Gwangju 61186Republicof Korea

Nb-based, perovskite-type oxynitrides ANb(O,N)_(3)(A = Sr, Ba) have been significantly attractive semiconductor materials for photoelectrochemical(PEC) water splitting due to their absorption abilities of intensive-visible-light. However, PEC activities of these perovskites are relatively low due to reduction of Nb species during nitridation leading to the generation of anion defects and impurity ***, we propose nitridation of A-rich, layered perovskite A_(5)Nb_(4)O_(15) as starting oxides for general synthesis of photoactive ANbO_(2)N. These layered perovskite A_(5)Nb_(4)O_(15) were completely transformed to single phase perovskite-type ANbO_(2)N by nitridation. Wavelength onsets of light absorption were observed at 700 nm for SrNbO_(2)N and at 740 nm for BaNbO_(2)N. According to X-ray photoelectron spectroscopy results,excess Lewis base A species significantly suppressed the generation of reduced species such as Nb^(4+) and Nb^(3+)during nitridation, although it led to an amorphous surface of the as-prepared *** annealing in Ar largely enhanced surface crystallinity of ANbO_(2)N. As a result, Co(OH)_(x)/ANbO_(2)N/FTO photoanodes, prepared by loading Co(OH)_(x) electrocatalyst, showed high photocurrent density of 1.6(A = Sr) and 2.4 m A cm^(-2)(A = Ba) at 1.23 VRHEunder AM 1.5 G simulated sunlight. These results demonstrate that A-rich layered perovskite A_(5)Nb_(4)O_(15)are effective starting precursors for preparing lowdefective ANbO_(2)N, thus improving PEC water splitting activity.

关键词： Perovskite-type oxynitride CaNbO_(2)N SrNbO_(2)N BaNbO_(2)N A-rich starting oxide Surface heat treatment Ar annealing Solar water oxidation

Taraxacum offlcinale protects against cholecystokinin-induced acute pancreatitis in rats

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World Journal of Gastroenterology 2005年第4期11卷 597-599页

作者： Sang-Wan seo Hyun-Na Koo Hyo-Jin An Kang-Beom Kwon Byung-Cheal Lim Eun-A seo Do-Gon Ryu Goo Moon Hong-Yeoul Kim Hyung-Min Kim seung-Heon Hong Department of Pharmacology College of Oriental Medicine Kyung Hee UniversitySeoul South Korea Department of Oriental PharmacyCollege of PharmacyWonkwang University Iksan Jeonbuk South Korea Department of Pharmacology College of Oriental Medicine Kyung Hee University Seoul South Korea Department of Pharmacology College of Oriental Medicine Kyung Hee University Seoul South Korea Department of Oriental PharmacyCollege of Pharmacy Wonkwang University Iksan Jeonbuk South Korea School of Oriental Medicine Wonkwang University IksanJeonbukSouth Korea Department of Food and Nutrition School of Human Environmental Science Wonkwang UniversityJeonbukSouth Korea Institute of Oriental Medicine College of Oriental Medicine Kyung Hee University SeoulSouth Korea Department of Pharmacology College of Oriental Medicine Kyung Hee UniversitySeoulSouth Korea Department of Oriental Pharmacy College of Pharmacy Wonkwang UniversityIksanJeonbukSouth Korea

AIM: Taraxacum officinale (TO) has been frequently used as a remedy for inflammatory diseases. The aim of this study was to investigate the effect of TO on cholecystokinin (CCK)-octapeptide-induced acute pancreatitis in ***: TO at 10 mg/kg was orally administered, followed by 75 μg/kg CCK octapeptide injected subcutaneously three times after 1, 3 and 5 h. This whole procedure was repeated for 5 d. We determined the pancreatic weight/body weight ratio, the levels of pancreatic HSP60 and HSP72, and the secretion of pro-inflammatory cytokines. Repeated CCK octapeptide treatment resulted in typical laboratory and morphological changes of experimentally-induced ***: TO significantly decreased the pancreatic weight/body weight ratio in CCK octapeptide-induced acute pancreatitis. TO also increased the pancreatic levels of HSP60 and HSP72. Additionally, the secretion of IL-6 and TNF-α decreased in the animals treated with ***: TO may have a protective effect against CCK octapeptide-induced acute pancreatitis.

关键词： Acute pancreatitis Taraxacum officinale CCK octapeptide

Involvement of lymphocytes in dextran sulfate sodium-induced experimental colitis

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World Journal of Gastroenterology 2006年第2期12卷 302-305页

作者： Tae Woon Kim Jae nam seo Young Ho Suh Hyo Jin Park Ju Hyun Kim Ji Young Kim Kwon Ik Oh Department of Pathology Hallym University College of MedicineChuncheonKorea Division of Metabolic Diseases Department of Biomedical SciencesNational Institute of HealthSeoulKorea Graduate Program of Immunology and Department of Pathology Seoul National University College of MedicineSeoulKorea

AIM： To investigate the roles of lymphocytes in the development of dextran sulfate sodium-induced colitis. METHODS： Using various doses of dextran sulfate sodium （DSS）, we induced colitis in wild-type B6 control and Rag-1 knockout （H-2b haplotype） mice, and evaluated the colitis in terms of symptomatic and histologic parameters, such as weight loss, survival, severity of diarrhea, shortage of colon length and histological changes. Symptomatic parameters were checked daily and histological changes were scored. RESULTS： Although development of colitis in Rag-1 knockout mice treated with high dose （5%） of DSS was comparable to that in B6 control mice, colitis progression was much more tolerable in Rag-1 knockout mice compared to than in B6 mice treated with low dose （1.5%） DSS. Symptomatic parameters as well as histopathologic changes were improved in Rag-1 knockout mice. CONCLUSION： These results indicate that the presence of lymphoo/tes contributes to colitis progression at low dose of DSS stimulation. Lymphoo/tes may play roles as an aggravating factor in DSS-induced colitis.

关键词： Dextran sulfate sodium Colitis Lymphocyte Rag-1 Knockout

Effect of Cristobalite and Quartz on the Properties of Gypsum Bonded Investment

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Journal of Materials Science & Technology 2008年第1期24卷 143-144页

作者： Yun-Jong Kim Sang-Bae Kim Hyun-Hye Park Myeong-Deok seo Byoung-Cheon Lee Man-So Han Taik-nam Kim Sung-Baek Cho Korea Institute of Geoscience and Mineral Resources (KIGAM) Gajeong-dong 30 Yuseong-kuDaejeon 305-350Korea Department of Materials Engineering Graduate School Paichai UniversityDaejeon 302-735Korea Dept.of Dental Laboratory Technology Daejeon Health Science College Korea

Generally the gold investment material consists of cristobalite,quartz and *** physical property of gold investment materials depends on its thermal expansion coefficients,compressive strength,and particles size *** the thermal expansion coefficient of cristobalite and quartz are 2.6×10^-6/℃and 2.32×10^-6/℃respectively,the composition ratio of each components influence the thermal and physical properties of gold investment *** the clinical applications,it is necessary to improve the properties of gold investment materials such as homogeneous size distribution and thermal expansion *** the present study,effect of inorganic fillers such as cristobalite and quartz on gold alloy investment was investigated to improve the properties of *** compressive strength and thermal expansion coefficients of the specimens were *** results showed that cristobalite and quartz were homogeneously distributed by milling. The optimum compressive strength was obtained at the ratio of 42：22 cristobalite and quartz,respectively.

关键词： Investment Cristobalite Quartz Thermal expansion coefficient Compressivestrength

Rapid determination of lithium-ion battery degradation: High C-rate LAM and calculated limiting LLI

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Journal of Energy Chemistry 2022年第4期31卷 663-671页

作者： Gyuwon seo Jaeyun Ha Moonsu Kim Jihyeon Park Jaewon Lee Eunoak Park Sungyool Bong Kiyoung Lee Soon Jong Kwon seung-pil Moon Jinsub Choi Jaeyoung Lee Electrochemical Reaction and Technology Laboratory School of Earth Sciences and Environmental EngineeringGwangju Institute of Science and Technology(GIST)Gwangju 61005South Korea Department of Chemistry and Chemical Engineering Inha UniversityIncheon 22212South Korea Ertl Center for Electrochemistry and Catalysis GISTGwangju 61005South Korea Korea Electric Power Corporation Research Institute Daejeon 34056South Korea International Future Research Center of Chemical Energy Storage and Conversion Processes(ifRC-CHESS) GISTGwangju 61005South Korea

Herein,incremental capacity-differential voltage (IC-DV) at a high C-rate (HC) is used as a non-invasive diagnostic tool in lithium-ion batteries,which inevitably exhibit capacity fading caused by multiple mechanisms during charge/discharge *** battery degradation modes are complex,the simple output of capacity fading does not yield any useful data in that *** IC and DV curves obtained under restricted conditions (<0.1C,25℃) were applied in non-invasive analysis for accurate observation of degradation symptoms,a facile,rapid diagnostic approach without intricate,complex calculations is critical in on-board ***,Li Ni_(0.5)Mn_(0.3)Co_(0.2)O_(2)(NMC532)/graphite pouch cells were cycled at 4 and 6C and the degradation characteristics,i.e.,loss of active materials (LAM) and loss of lithium inventory (LLI),were parameterized using the IC-DV *** the incremental current cycling,the initial steep LAM and LLI slopes underwent gradual transitions to gentle states and revealed the gap between low-and high-current measurements.A quantitative comparison of LAM at high and low C-rate showed that a IC;revealed the relative amount of available reaction region limited by cell ***,this did not provide a direct relationship for estimating the LAM at a low ***,the limiting LLI,which is calculated at a C-rate approaching 0,was obtained by extrapolating the LLI through more than two points measured at high C-rate,and therefore,the LLI at 0.1C was accurately determined using rapid cycling.

关键词： Battery degradation Rapid degradation diagnosis Loss of active materials(LAM) Loss of lithium inventory(LLI) Incremental capacity(IC) Differential voltage(DV)

Mott insulator-superfluid phase transition in a detuned multi-connected Jaynes-Cummings lattice

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Science China(Physics,Mechanics & Astronomy) 2015年第7期58卷 17-22页

作者： seo Kangjun TIAN Lin School of Natural Sciences University of California

The connectivity and tunability of superconducting quantum devices provide a rich platform to build quantum simulators and study novel many-body physics. Here we study quantum phase transition in a detuned multi-connected Jaynes-Cummings lattice, which can be constructed with superconducting circuits. This model is composed of alternatively connected qubits and cavity *** a numerical method, we show that by varying the detuning between the qubits and the cavities, a phase transition from the superfluid phase to the Mott insulator phase occurs at commensurate fillings in a one-dimensional array. We study the phase transition in lattices with symmetric and asymmetric couplings, respectively.

关键词： superconducting quantum devices quantum simulation Jaynes-Cummings lattice phase transition