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Isotope Geochemistry of Volcanic Rocks from the Barton Peninsula,King George Island,Antarctica

Journal of Earth Science 2011年第1期22卷 40-51页

作者： jeong Hwang 郑祥身 Edward M Ripley Jong-Ik Lee Dongbok shin Department of Geological Engineering Daejeon University Institute of Geology and Geophysics Chinese Academy of Sciences Department of Geological Sciences Indiana University Korea Polar Research Institute Department of Geological Sciences Kongju University

C, O, H, S and Sr isotopes were investigated to characterize the isotopic composition of the Paleocene-Eocene volcanic rocks in Barton Peninsula, King George Island, Antarctica. The analyzed samples of volcanic rocks cover a range from basalt to andesite. The δ 13C and 61SO values of calcite in volcanic rocks range from -7.5‰ to -3.2‰ and 0.4‰ to 5.1‰, respectively. The homogenous δ 13C cal and depleted δ18 Ccal values relative to primary magmatic values reflect the effect of high temperature alteration of volcanic rocks. The δ18 O of volcanic rocks ranges from -1.1‰ to 7.2‰, and the majority of values are significantly lower than those of primary magmatic values. The low δ18 O WR values are compatible with high temperature alteration. The initial values of 87Sr/86Sr of volcanic rocks span a narrow range from 0.703 312 to 0.703 504 which belong to the present mid-oceanic ridge basalt. The values of 87Sr/86Sr of volcanics in the Barton Peninsula are similar to those determined in the Fildes Peninsula, King George Island. The δD WR and H2O contents of volcanic rocks range from -74‰ to -66‰ and 0.67 wt.% to 2.74 wt.%, respectively. The higher δD WR and H2O wt.% of volcanic rocks relative to fresh basalts also result from high temperature alteration. Sulfur isotope compositions of the volcanic rocks range from -12.5‰ to -7.0‰; these values may represent fractionation accompanying partial oxidation of magmatic S or incorporation of some bacteriogenic sulfide. The low S contents and negative correlation with C and H2O reflect the formation of calcite and breakdown of sulfide as a result of high temperature water-rock interaction.

关键词： isotope volcanic rock high temperature alteration Antarctica.

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Development of an analytical method for multi-residue quantification of 18 anthelmintics in various animal-based food products using liquid chromatography-tandem mass spectrometry

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Journal of Pharmaceutical Analysis 2021年第1期11卷 68-76页

作者： Kyung-Hee Yoo Da-Hee Park A.M.Abd El-Aty Seong-Kwan Kim Hae-Ni Jung Da-Hye jeong Hee-Jung Cho Ahmet Hacimuftuoglu Jae-Han Shim Ji hoon jeong ho-Chul shin Department of Veterinary Pharmacology and Toxicology College of Veterinary MedicineKonkuk UniversitySeoul143-701Republic of Korea State Key Laboratory of Biobased Material and Green Papermaking College of Food Science and EngineeringQilu University of TechnologyShandong Academy of ScienceJinan250353China Department of Pharmacology Faculty of Veterinary MedicineCairo University12211GizaEgypt Department of Medical Pharmacology Medical FacultyAtaturk UniversityErzurum25240Turkey Department of Veterinary Physiology College of Veterinary MedicineKonkuk UniversitySeoul143-701Republic of Korea Natural Products Chemistry Laboratory College of Agriculture and Life SciencesChonnam National UniversityGwangju500-757Republic of Korea Department of Pharmacology College of MedicineChung-Ang UniversitySeoul156-756Republic of Korea

In this study,we developed a simple screening procedure for the determination of 18 anthelmintics(including benzimidazoles,macrocyclic lactones,salicylanilides,substituted phenols,tetrahydropyrimidines,and imidazothiazoles)in five animal-derived food matrices(chicken muscle,pork,beef,milk,and egg)using liquid chromatography-tandem mass *** were extracted using acetonitrile/1% acetic acid(milk and egg)and acetonitrile/1% acetic acid with 0.5 mL of distilled water(chicken muscle,pork,and beef),and purified using saturated n-hexane/acetonitrile.A reversed-phase analytical column and a mobile phase consisting of(A)10 mM ammonium formate in distilled water and(B)methanol were used to achieve optimal chromatographic ***-matched standard calibration curves(R^(2)≥0.9752)were obtained for concentration equivalent to ×1/2,×1,×2,×3,×4,and×5 fold the maximum residue limit(MRL)stipulated by the Korean Ministry of Food and Drug *** of 61.2e118.4%,with relative standard deviations(RSDs)of ≤19.9%(intraday and interday),were obtained for each sample at three spiking concentrations(×1/2,×1,and ×2 the MRL values).Limits of detection,limits of quantification,and matrix effects were 0.02e5.5 mg/kg,0.06e10 mg/kg,and -98.8 to 13.9%(at 20 μg/kg),*** five samples of each food matrix(chicken muscle,pork,beef,milk,and egg)purchased from large retailers in Seoul that were tested,none of the target analytes were *** has therefore been shown that this protocol is adaptable,accurate,and precise for the quantification of anthelmintic residues in foods of animal origin.

关键词： Anthelmintics Tandem mass spectrometry Animal-based food products Residue analysis Method validation

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Spatial distribution and comparative evaluation of phosphorus release rate in benthic sediments of an estuary dam

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International Journal of Sediment Research 2022年第3期37卷 355-369页

作者： Yongsik Song Yong-hoon jeong Chang-Min shin Dong-Heui Kwak Geosystem Research Corporation Department of Civil Engineering Jeonbuk National University Department of Bio-Convergence Science Jeonbuk National University Water Quality Assessment Research Division National Institute of Environmental Research Department of Bioactive Materials Science Jeonbuk National University

A series of experiments and simulations were performed to ascertain the rate at which phosphorus is released using a water quality model in Saemangeum Lake, an artificially constructed lake located in an estuary. The general inflow of seawater once a day contributed to the formation of a halocline in the lake water, which caused variation in the vertical concentration of dissolved oxygen. The halocline was mainly observed in the deep downstream regions of Saemangeum Lake that are close to the open sea. In contrast, the shallower regions upstream, which are under the influence of pollutant-loading from upstream rivers, exhibited high concentrations of chemical oxygen demand, total phosphorus, and Chl-a,resulting in lower water quality than the downstream regions. Laboratory experiments investigating the release of phosphorus at five representative locations showed that the upstream release flux, where the halocline was weaker, was higher than that downstream, where the initial level of phosphorus sedimentation was high. In particular, a need for an accurate evaluation method for the release of phosphorus at each site was suggested as slight differences were obtained depending on the estimation method used at each representative location. The results of the phosphorus release experiments led to the use of time-weighted integration(TWI), terminated time evaluation, and statistical mean value; the Environmental Fluid Dynamics Code-National Institute of Environment Research model, a widely used water quality model for studying retention watersheds, was applied to the simulation of hydraulic and water quality characteristics for the Saemangeum Lake and its surrounding waters. The result of the water quality simulation indicated the highest reproducibility for release-time TWI so that TWI values were more useful in predicting phosphorus concentrations and the subsequent management of water quality.

关键词： Eutrophication Phosphorus release Salinity Sediments Water quality simulation Environmental Fluid Dynamics Code–National Institute of Environment Research model (EFDC-NIER)

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Optic radiation injury in patients with aneurismal subarachnoid hemorrhage: a preliminary diffusion tensor imaging report

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Neural Regeneration Research 2018年第3期13卷 563-566页

作者： Sung ho Jang Chul hoon Chang Young Jin Jung Seong ho Kim jeong Pyo Seo Department of Physical Medicine and Rehabilitation College of Medicine Yeungnam University Department of Neurosurgery College of Medicine Yeungnam University

Visual field defect is one of the various clinical manifestations in patients with subarachnoid hemorrhage（SAH）. Little is known about the pathogenic mechanism of visual field defect in SAH. In the current study,we investigated the diffusion tensor imaging （DTI） finding of the optic radiation in patients with SAH followingrupture of a cerebral artery aneurysm. We recruited 21 patients with aneurismal SAH （12 males, 9 females, mean age, 52.67 years; range, 41–68 years） who showed no definite lesion along the visual ***-one age-and sex-matched normal control subjects were also recruited. DTI data were acquired at an average of 5.9 weeks （range： 3–12 weeks） after onset and reconstruction of the optic radiation was performed using DTI-Studio software. The fractional anisotropy value, apparent diffusion coefficient value,and fiber number of the optic radiation were measured. The fractional anisotropy value of the optic radiation was significantly decreased, and the apparent diffusion coefficient value was significantly increased, in patients with aneurismal SAH than in normal control subjects. however, there was no significant difference in the fiber number of the optic radiation between patients with aneurismal SAH and normal control subjects. The decrement of fractional anisotropy value and increment of apparent diffusion coefficient value of the optic radiation in patients with aneurismal SAH suggest optic radiation injury. Therefore, we recommend a thorough evaluation for optic radiation injury in patient with aneurismal SAH.

关键词： nerve regeneration diffusion tensor imaging optic radiation subarachnoid hemorrhage visual field defect neural regeneration

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Clinical significance of hepatitis B e antigen level measurement during long-term lamivudine therapy in chronic hepatitis B patients with e antigen positive

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World Journal of Gastroenterology 2006年第41期12卷 6693-6698页

作者： Jung Woo shin Neung Hwa Park Seok Won Jung Byung Chul Kim Sung ho Kwon Jae Serk Park In Du jeong Sung-Jo Bang Do Ha Kim Division of Gastroenterology Department of Internal MedicineUniversity of Ulsan College of Medicine Ulsan University HospitalUlsanKorea

AIM： To determine the changes of quantitative hepatitis B e antigen （HBeAg） that predicts early detection of non-response or breakthrough to long-term lamivudine （LAM） therapy. METhoDS： Among HBeAg positive chronic hepatitis B patients who failed to achieve HBeAg seroconversion within 12 too, we retrospectively analyzed 220 patients who had received LAM more than 24 too. RESULTS： The mean duration of LAM therapy was 36 （range, 24-72） mo. HBeAg seroconversion after the first 12 mo of LAM therapy was achieved in 53 （24.1%） patients. Viral breakthrough was observed in 105 （47.7%） patients. To find out whether the changing patterns of HBeAg levels can predict the outcome of LAM therapy, we analyzed the reduction rates of HBeAg levels during LAM therapy. Using the decrease more than 90% of pretreatment HBeAg levels, the sensitivity and specificity of response were 96.2% and 70.1%, respectively. Patients were divided into 3 groups according to the reduction patterns of the decrease of quantitative HBeAg： decrescendo, decrescendo-crescendo, no change or fluctuating groups. The optimal time to predict non-response or breakthrough was the first 9 mo of therapy. At 9 mo of therapy, 49 （92.5%） of 53 patients who had achieved HBeAg seroconversion were included in the decrescendo group. On the contrary, in the no change or fluctuating group, only four （7.5%） had achieved HBeAg seroconversion. Among patients who did not show the continuous decrease of HBeAg levels at 9 too, 95.2% （negative predictive value） failed to achieve HBeAg seroconversion. CONCLUSION： Almost all patients who failed to show a continuous decrease of HBeAg levels at 9 mo of LAM therapy were non-response or breakthrough. Therefore, monitoring changes of HBeAg levels during LAM therapy in HBeAg positive chronic hepatitis B may be valuable for identifying patients who are at high risk of non-response or breakthrough.

关键词： Hepatitis B e antigen positive chronic hepatitis B lamivudine Quantitative HBeAg levels Non- response Breakthrough

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Aqueous-processable,naphthalene diimide-based polymers for eco-friendly fabrication of high-performance,n-type organic electrolyte-gated transistors

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Science China Chemistry 2022年第5期65卷 973-978页

作者： Dahyun jeong Min Je Kim Seungjin Lee Jin-Woo Lee Youngwoong Kim Hyeong Jun Kim jeong ho Cho Bumjoon J.Kim Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea Department of Chemical and Biomolecular Engineering Yonsei UniversitySeoul 03722Republic of Korea Department of Chemical and Biomolecular Engineering Sogang UniversitySeoul 04107Republic of Korea

Organic electrolyte-gated transistors(OEGTs) have the benefits of low power consumption and large current ***,the electrical performance of n-type OEGTs lags far behind that of p-type *** this study,we design a series of polymers,P(NDITEG-T) and P(NDIMTEG-T),comprising a naphthalene diimide backbone for n-type charge transport and oligo(ethylene glycol)(OEG) side chains for high ionic conductivity and eco-friendly solution *** incorporation of the OEG chain facilitates the electrochemical doping of the semiconductor by ions to realize high-performance,n-type ***,in OEGTs,P(NDITEG-T) achieves a high electron mobility of 1.0 × 10^(-1) cm^(2) V^(-1) s^(-1),which represents the highest value reported for solution-processed,n-type *** is noted that the fabrication of the OEGTs is achieved by solution processing with eco-friendly ethanol/water mixtures in virtue of the hydrophilic OEG *** work demonstrates the molecular design of the P(NDITEG-T) polymer and its significant ability to produce aqueous-processable,high-performance,and n-type OEGTs.

关键词： organic electrolyte-gated transistors n-type transistors oligo(ethylene glycol)polymers eco-friendly solution process high electron mobility

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Synthesis of Co/SiO2 hybrid nanocatalyst via twisted Co3Si2O5（OH）4 nanosheets for high-temperature Fischer- Tropsch reaction

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Nano Research 2017年第3期10卷 1044-1055页

作者： Ji Chan Park shin Wook Kang jeong-Chul Kim Jae In Kwon Sanha Jang Geun Bae Rhim Mijong Kim Dong Hyun Chun ho-Tae Lee Heon Jung Hyunjoon Song Jung-li Yang Clean Fuel Laboratory Korea Institute of Energy Research Daejeon 34129 Republic of Korea Advanced Energy Technology University of Science and Technology Daejeon 34713 Republic of Korea Center for Nanomaterials & Chemical Reactions Institute for Basic Science Daejeon 34141 Republic of Korea Department of Chemistry Korea Advanced Institute of Science and Technology Daejeon 34141 Republic of Korea

A cobalt-silica hybrid nanocatalyst bearing small cobalt particles of diameter -5 nm was prepared through a hydrothermal reaction and hydrogen reduction. The resulting material showed very high CO conversion （〉82%） and high hydrocarbon productivity （-1.0gHC·gcat^-1·h^-1 ） with high activity （-8.5 × 10^-5 ***^-1.s-1） in the Fischer-Tropsch synthesis reaction.

关键词： hybrid nanostructure Fischer-Tropsch synthesis thermal stability metal silicate hydroxide cobalt catalyst

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High-efficiency technique based on dielectrophoresis for assembling metal,semiconductor,and polymer nanorods

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第5期12卷 368-373页

作者： Heng YUAN Kyu-jin KIM Won-seok KANG Byoung-ho KANG Se-hyuk YEOM Jae-ho KIM shin-won KANG School of Electrical Engineering and Computer Science Kyungpook National University 1370 Sankyuk-dong Bukgu Daegu 702-701 Korea) Department of Molecular Science and Technology Ajou University San s.Woncheon-dongYeongtong-guSuwon 443-749Korea School of Electronic Engineering College oflT Engineering Kyungpook National University 13 70 Sankyuk-dong Bukgu Daegu 702-701 Korea

This paper presents a high-efficiency technique based on dielectrophoresis (DEP) for assembling metal, semiconductor, and polymer nanorods, which are synthesized by electrochemical deposition (ECD). The assembly patterns of these nanorods (width: 20 nm; length: 7 μm) were designed using a finite element method (FEM) simulation tool. Further, these nanorods were used in our experiment after their assembly patterns were fabricated. The assembly yield was found to be approximately 70% at an AC voltage of 30 Vp-p and at frequencies of 20 and 30 kHz, and the DC voltage prevented the random alignment of the nanorods at the edge of the assembly pattern. Moreover, the above-mentioned nanorods, which had different permittivities, were found to have similar assembly yields. The proposed method can be improved and applied to nanostructure device fabrication.

关键词： Nanorod Assembly Dielectrophoresis (DEP) Finite element method (FEM) Electrochemical deposition (ECD) method

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Sound transducer calibration of ambulatory audiometric system utilizing delta learning rule

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Journal of Central South University 2011年第6期18卷 2009-2014页

作者： KIM Kyeong-seop shin Seung-won YOON Tae-ho LEE Sang-min LEE Insung RYU Keun ho School of Biomedical Engineering Konkuk University Xiu Solution Co. Ltd. Department of Electronic Engineering Inha University Department of Radio Communication Engineering Chungbuk National University Database/Bioinformatics Lab Chungbuk National University

An efficient calibration algorithm for an ambulatory audiometric test system is proposed. This system utilizes a personal digital assistant (PDA) device to generate the correct sound pressure level (SPL) from an audiometric transducer such as an earphone. The calibrated sound intensities for an audio-logical examination can be obtained in terms of the sound pressure levels of pure-tonal sinusoidal signals in eight-banded frequency ranges (250, 500, 1 000, 2 000, 3 000, 4 000, 6 000 and 8 000 Hz), and with mapping of the input sound pressure levels by the weight coefficients that are tuned by the delta learning rule. With this scheme, the sound intensities, which evoke eight-banded sound pressure levels by 5 dB steps from a minimum of 25 dB to a maximum of 80 dB, can be generated without volume displacement. Consequently, these sound intensities can be utilized to accurately determine the hearing threshold of a subject in the ambulatory audiometric testing environment.

关键词： calibration audiometric system pure-tonal sound sound pressure level heating threshold delta learning rule

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Flow characteristics of aluminum coated boron steel in hot press forming

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中国有色金属学会会刊：英文版 2009年第4期19卷 913-916页

作者： jeong-Hwan JANG Jae-ho LEE Bye ong-Don JOO Young-hoon MOON School of Mechanical Engineering Pusan National University

The flow characteristics of aluminum coated boron steel in hot press forming were ***,the effects of aluminum coated layer on press forming were analyzed during deep *** results show that aluminum coated boron steel exhibits a high sensitivity on temperature and strain *** coating layer appears in surface flaking in a temperature range of 700-800 ℃,but smooth surface is formed above 900 ℃.

关键词：热压成型流动特性铝涂层硼钢表面剥落温度范围冲压成形高灵敏度

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