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microstructure characteristics and effect of grain orientation on magnetic properties of Fe_(63)Co_(32)Gd_5 alloy ribbons

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Journal of Central South University 2015年第6期22卷 2014-2019页

作者：姚文静王楠 LEE je-hyun Key Laboratory of Space Applied Physics and Chemistry of ministry of Education School of Science Northwestern Polytechnical University Engineering Research Center for Integrated mechatronics materials and Components Changwon National University

By using the melt spinning techniques, the Fe63Co32Gd5 alloy ribbons with 15-50 m in thickness and 3-7 mm in width were prepared at the wheel speeds of 15, 20, 25 and 35 m/s. The rapid solidification microstructures were characterized by three layers, the middle layer of which reaches 80% thickness and forms the column grain of(Fe,Co) solid with Gd solution. Grain refinement takes place with the increase of the wheel speed. And after 0.5 h heat treatment at 823 K, the ribbon thickness becomes larger and the middle layer of column grain is very orderly perpendicular to the ribbon plane. The coercivity of quenched and annealed Fe63Co32Gd5 ribbons both have the inflection point at the wheel speed of 20 m/s, and the tendency is declining. The heat treatment processing makes the coercivity become lower by improving the order of(Fe,Co)17Gd2 compound. The saturation magnetization of quenched ribbons increases with the enhancement of wheel speed, whereas that of annealed ones decreases firstly and then increases. The minimum coercivity is 5.30×103 A/m and the maximum saturation magnetization is 163.62 A·m2/kg, which is obtained in the conditions of the wheel speed of 35 m/s and 0.5 h heat treatment at the temperature of 823 K.

关键词： Fe-Co-Gd alloy ribbon rapid solidification phase composition magnetic properties

A taxonomic review of the genus miaenia Pascoe, 1864(Coleoptera: Cerambycidae) from South Korea with a new record of m. tonsa(Bates)

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Journal of Forestry Research 2018年第3期29卷 822-829页

作者： Ik je Choi Tae Sung Kwon Jongok Lim Silkworm and Insect management Center Gyeongsangbuk-do Agricultural Resource Management Institute Forest Insect Pests and Disease Division Korea Forest Research Institute Division of Forest Biodiversity Korea National Arboretum

The cerambycid genus miaenia Pascoe(Coleoptera: Cerambycoidea) of South Korea is taxonomically reviewed. Two species, miaenia fasciata fasciata(matsushita) and miaenia maritima Tsherepanov have been recorded. In this paper, m. tonsa(Bates) is added to the Korean cerambycid fauna for the first time. A key to Korean miaenia species, re-description and diagnostic illustrations, including male genitalia for each species, are provided.

关键词： Acanthocinini Cerambycidae miaenia New species South Korea Taxonomy

In vivo antiplasmodial activities of ethanolic exract and fractions of Eleucine indica

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Asian Pacific Journal of Tropical medicine 2012年第9期5卷 673-676页

作者： Ettebong EO Nwafor PA Okokon je Department of Pharmacology and Toxicology Faculty of PharmacyP.M.B.1017University of UyoUyoNigeria

Objective:To evaluate the in rivo antiplasmodial activities of the extract and fractions(n-hexane. chloroform,***) of the whole plant in Plasmodium berghei berghei infected ***:Oral administrations of the extract(200.400,and 600 my/kg) of Eleacine indica and fractions(400 mg/kg) were screened in the *** and curative tests. Chloroquine(5 mg/kg).pyrimethamine(1.2 mg/kgi and artesunate(5 mg/kgi were used as controls. Results:The extract showed significant[Pmodial activity in the *** and curative tests and increased the survival times of the infected mice. All the fractions exhibited significant antiplasmodial activity with the highest being ethylacetate ***:Eleucine indica extract and fractions possess antimalarial activity which confirms the ethnobotanical use of this plant as a malarial remedy and opens a new highway to further investigate its potentials in the on-going fight against malaria.

关键词： Antimalarial activity Alkaloid Plasmodium berghei berghei Eleucine indica

Estimation of plasma density perturbation from dusty plasma injection by laser irradiation on tungsten target in DiPS

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Plasma Science and Technology 2020年第4期22卷 90-96页

作者： In je KANG min-Keun BAE In Sun PARK min Ji LEE Kyu-Sun CHUNG Department of Electrical Engineering Hanyang UniversitySeoul 133791Republic of Korea Plasma Technology Research Center National Fusion Research InstituteGunsan 54004Republic of Korea

To investigate the interaction of dusty plasma with magnetized plasmas at divertor plasma simulator,radial profiles of plasma density(ne)and electron temperature were measured in terms of plasma discharge currents and magnetic flux intensity by using a fast scanning probes system with triple *** plasma with dusts(a generation rate of 3μg s-1 and a size of 1–10μm)was produced via interactions between a high-power laser beam and a full tungsten *** ne increases,the scale of the effects of dusty plasma injection on magnetized plasmas was ***,the duration of transient fluctuation was *** numerical estimation of plasma density perturbation due to dusty plasma injection,the result was 10%at a core region of the magnetized plasma with ne of(2–5)×10^11 cm^-3 at steady state condition.

关键词： plasma density perturbation dusty plasma tungsten dust DiPS

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魔芋多糖的制备、抗氧化活性及其结构表征

粮食与油脂 2024年第6期37卷 134-140页

作者：问小龙李亚杰张亮邹迎春谭林海向极钎恩施土家族苗族自治州农业科学院湖北恩施445000 恩施硕品现代农业科技有限责任公司湖北恩施445000 湖北省富硒产业技术研究院湖北恩施445000

以魔芋精粉为原料,采用超声辅助热水浸提魔芋多糖。通过单因素和响应面试验,确定魔芋多糖的最优提取工艺,并对其抗氧化活性和结构特征进行分析。结果表明:在超声时间50 min、超声功率1224 W、提取温度76.5℃的最佳条件下,所得魔芋多糖... 详细信息

以魔芋精粉为原料,采用超声辅助热水浸提魔芋多糖。通过单因素和响应面试验,确定魔芋多糖的最优提取工艺,并对其抗氧化活性和结构特征进行分析。结果表明:在超声时间50 min、超声功率1224 W、提取温度76.5℃的最佳条件下,所得魔芋多糖得率为74.3%。当魔芋多糖质量浓度为2 mg/mL时,其对羟基自由基、DPPH自由基和ABTS自由基的清除率分别为77.05%、82.16%和25.82%。纯化后的魔芋多糖,以相对分子质量较小的成分为主;红外光谱分析表明魔芋多糖具有吡喃糖单元;扫描电镜显示魔芋多糖的立体结构是由0.5~2μm的立方体夹杂部分小颗粒聚集而成,单糖组成主要为葡萄糖和甘露糖。

关键词：魔芋多糖抗氧化活性结构表征

Thermoelectric properties of solution-synthesized n-type Bi2Te3 nanocomposites modulated by Se： An experimental and theoretical study

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Nano Research 2016年第1期9卷 117-127页

作者： Haiyu Fang je-Hyeong Bahk Tianli Feng Zhe Cheng Amr m. S. mohammed Xinwei Wang Xiulin Ruan Ali Shakouri Yue Wu School of Chemical Engineering Purdue University West Lafayette IN 47907 USA Birck Nanotechnology Center Purdue University West Lafayette IN 47907 USA School of mechanical Engineering Purdue University West Lafayette IN 47907 USA Department of mechanical Engineering Iowa State University Ames IA 50011 USA Department of Chemical and Biological Engineering Iowa State University Ames IA 50011 USA

We report the investigation of the thermoelectric properties of large-scale solution-synthesized Bi2Te3 nanocomposites prepared from nanowires hot- pressed into bulk pellets. A third element, Se, is introduced to tune the carrier concentration of the nanocomposites. Due to the Se doping, the thermoelectric figure of merit （ZT） of the nanocomposites is significantly enhanced due to the increased power factor and reduced thermal conductivity. We also find that thermal transport in our hot-pressed pellets is anisotropic, which results in different thermal conductivities along the in-plane and cross-plane directions. Theoretical calculations for both electronic and thermal transport are carried out to establish fundamental understanding of the material system and provide directions for further ZT optimization with adjustments to carrier concentration and mobility.

关键词： Bi2Te3 Se doping solution synthesis nanostructure thermoelectric

Study of sexual behaviour in relation to sexually transmitted infections(STIs) among Nigerian undergraduates

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Asian Pacific Journal of Tropical medicine 2009年第6期2卷 71-77页

作者： Agan TU Ekabua je Nyong PP Ndifon WO Itam HI Department of Obstetrics & Gynaecology University of Calabar Nigeria Department of Community medicine

Objective:To determine their reproductive health behaviour concerning fidelity and psychosocial intimacy in the face of current trends in sexually transmitted infections(STIs) and human immunodeficiency virus(HIV)/ acquired immune deficiency syndromes(AIDS) ***:A cross-sectional comparative male/female cohort study using a semi-structured questionnaire to interview sexually activity of undergraduates in University of Calabar(UNICAL) was conducted over a three(3) month period in *** used were number of sexual partners,frequency of sexual intercourse in the 6 months preceding,knowledge of last menstrual period(LmP),methods of self-protection against STIs,number of unwanted pregnancies terminated,and contraceptive ***:Of the 1 337 respondents,648 out of 684 males(94.7%) and 543 out of 653 females (83.2%) had multiple sex *** gender difference was statistically significant(P males and 110(16.9%) of females maintained single mates in the past six *** half of females(320,49.0%) and 314(45.9%) of males exhibited spontaneous sexual contact *** difference in frequency of intercourse between both groups was not statistically significant(P >0.05).While 275(42.0%) of the females could state the exact last menstrual period(LmP),only 14(2.1%) males could remember their mates LmP,and 496(72.5%) of males did not know anything about mates’menstrual *** was no statistical significance difference(P >0.05 ) between both groups in their safe sex practices. One hundred and sixty three(23.8%) male and one hundred and forty one(22.8%) females used condoms,while 347(50.7%) of male and 337(51.6%) of females did *** hundred and seventy six(40.0%) of males’mates had terminated pregnancies and three hundred and forty eight(53.3%) of female respondents admitted doing ***(4.60%) females terminated pregnancy more than six *** had more knowledge of contraceptives but males used

关键词： Sexual intimacy Undergraduates Safe-sex

Ultrasonic Plasma Engineering Toward Facile Synthesis of Single-Atom m-N4/N-Doped Carbon(m=Fe,Co) as Superior Oxygen Electrocatalyst in Rechargeable Zinc-Air Batteries

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Nano-micro Letters 2021年第4期13卷 76-95页

作者： Kai Chen Seonghee Kim minyeong je Heechae Choi Zhicong Shi Nikola Vladimir Kwang Ho Kim Oi Lun Li Department of materials Science and Engineering Pusan National University30 Jangjeon‑dongGeumjeong‑guBusan 609‑735Republic of Korea Theoretical materials and Chemistry Group Institute of Inorganic ChemistryUniversity of CologneGreinstr.650939 CologneGermany School of materials and Energy Guangdong University of TechnologyGuangzhou 510006People’s Republic of China Faculty of mechanical Engineering and Naval Architecture University of ZagrebIvana Lucica 510002 ZagrebCroatia Global Frontier R&D Center for Hybrid Interface materials 30 Jangjeon‑dongGeumjeong‑guBusan 46241Republic of Korea

As bifunctional oxygen evolution/reduction electrocatalysts,transition-metal-based single-atom-doped nitrogen-carbon(NC)matrices are promising successors of the corresponding noblemetal-based catalysts,offering the advantages of ultrahigh atom utilization effciency and surface active ***,the fabrication of such matrices(e.g.,well-dispersed single-atom-doped m-N4/NCs)often requires numerous steps and tedious ***,ultrasonic plasma engineering allows direct carbonization in a precursor solution containing metal phthalocyanine and *** combining with the dispersion effect of ultrasonic waves,we successfully fabricated uniform single-atom m-N4(m=Fe,Co)carbon catalysts with a production rate as high as 10 mg *** Co-N4/NC presented a bifunctional potential drop ofΔE=0.79 V,outperforming the benchmark Pt/C-Ru/C catalyst(ΔE=0.88 V)at the same catalyst *** calculations revealed that Co-N4 was the major active site with superior O2 adsorption-desorption *** a practical Zn-air battery test,the air electrode coated with Co-N4/NC exhibited a specific capacity(762.8 mAh g(-1))and power density(101.62 mW cm^(-2)),exceeding those of Pt/C-Ru/C(700.8 mAh g^(-1) and 89.16 mW cm^(-2),respectively)at the same catalyst ***,for Co-N4/NC,the potential difference increased from 1.16 to 1.47 V after 100 charge-discharge *** proposed innovative and scalable strategy was concluded to be well suited for the fabrication of single-atom-doped carbons as promising bifunctional oxygen evolution/reduction electrocatalysts for metal-air batteries.

关键词： Single-atom-doped m-N4/NC catalyst Plasma engineering ORR/OER bifunctional activity DFT calculation Rechargeable Zn-air battery

Effect of platinum on the photocatalytic degradation of chlorinated organic compound

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Journal of Environmental Sciences 2011年第4期23卷 687-692页

作者： Chih ming ma Ya Wen Lee Gui Bing Hong Te Li Su je Lueng Shie Chang Tang Chang Department of Cosmetic Application and management St. Mary's Medicine Nursing and Management College Yilan County 266 Taiwan China. Department of Environmental Engineering I-Lan University Yilan City 260 Taiwan China

TiO 2 nanoparticles, doped with different Pt contents, were prepared by a modified photodeposition method using Degussa P-25 TiO 2 , H 2 PtCl 6 ·6H 2 O and methanol as the solvents. The physicochemical properties of Pt/TiO 2 were investigated by the nitrogen adsorption and desorption isotherm measurement technique, X-ray diffraction analysis and photoluminescence spectra, respectively. Reaction rates from photocatalytic removal of dichloromethane over Degussa P-25 TiO 2 and Pt/TiO 2 were evaluated. The average diameter and BET surface area of the TiO 2 catalyst particles were 300 nm and 50 m 2 /g, respectively. The degradation efficiency was 99.0%, 82.7%, 55.2%, and 57.9% with TiO 2 at inlet concentrations of 50, 100, 200, and 300 ppm, respectively. And the degradation efficiency was 99.3%, 79.7%, 76.5%, and 73.4% with a 0.005 wt.% Pt/TiO 2 at inlet concentrations of 50, 100, 200, and 300 ppm, respectively. In addition, we found that the photoluminescence emission peak intensities decreased with increases in the doping amount of Pt, which indicates that the irradiative recombination was weakened. Furthermore, the results showed that the UV/0.005 wt.% Pt/TiO 2 process was capable of efficiently decomposing gaseous DCm in air.

关键词： dichloromethane photodeposition method platinum TiO 2 light intensity