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Thermodynamics calculation on the oxidation and sulfur removal abilities of slag in EAF dust pellet reduction process

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Journal of Central South University of Technology 2001年第1期8卷 64-68页

作者： PENG Bing 1,PENG Ji 1,zhang Chuan fu 1,jonathan Lobel 2,Janusz A. Kozinski 2 (1 Department of Metallurgical Science and Engineering, Central South University, Changsha 410083, China 2 Department of Metallurgical Engineering, McGill University Department of Metallurgical Science and Engineering Central South University Changsha China Department of Metallurgical Engineering McGill University Montreal Canada

The valuable metals in the dust can be recycled by mixing it with reducing agent carbon and lignosulfonate as the binder to make pellets, then returning the pellets to electric arc furnace (EAF) and adding ferro silicon. Part of valuable metals in the dust is reduced by carbon and part of them reduced by ferro silicon for the economical consideration. The reduced metals get into the steel in the stainless steel or special steel production. But the sulfur in the lignosulfonate may affect the quality of produced steel, which is dependent on the status of the smelting slag. The experiments were conducted in the way of changing the ratio of start iron, pellets, ferro silicon and lime. The content of the slag was checked by XRF for the calculation thermodynamics study. The active concentrations of materials in the slag, the slag abilities of oxidation and sulfur removal in EAF dust reduction process were determined by thermodynamics calculation study on CaO MgO FeO Fe 2O 3 SiO 2 S slag at 1 550 ℃. The oxidation ability of slag can be expressed as N (FetO)= N (FeO)+6 N (Fe 2O 3)+8 N (Fe 3O 4). The sulfur removal ability is dependent on the amount of added ferro silicon and the basicity of the slag. The calculation thermodynamics model was set up and it could be applied to the practical production.

关键词： thermodynamics calculation slag electric arc furnace dust

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Ambient synthesis, characterization, and electrochemical activity of LiFePO4 nanomaterials derived from iron phosphate intermediates

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Nano Research 2015年第8期8卷 2573-2594页

作者： jonathan M. Patete Megan E. Scofield Vyacheslav Volkov Christopher Koenigsmann Yiman zhang Amy C. Marschilok Xiaoya Wang Jianming Bai Jinkyu Han Lei Wang Feng Wang Yimei Zhu Jason A. Graetz Stanislaus S. Wong Department of Chemistry State University of New York at Stony Brook Stony Brook NY 77794-3400 USA Condensed Matter Physics and Materials Sciences Department Building 480 Brookhaven National Laboratory Upton NY 11973 USA Department of Materials Science and Engineering State University of New York at Stony Brook Stony Brook NY 11794-2275 USA Sustainable Energy Technologies Department Building 815 Brookhaven National Laboratory Upton NY 11973 USA National Synchrotron Light Source II Building 741 Brookhaven National Laboratory Upton NY 11973 USA

LiFePO4 materials have become increasingly popular as a cathode material due to the many benefits they possess including thermal stability, durability, low cost, and long life span. Nevertheless, to broaden the general appeal of this material for practical electrochemical applications, it would be useful to develop a relatively mild, reasonably simple synthesis method of this cathode material. Herein, we describe a generalizable, 2-step methodology of sustainably synthesizing LiFePO4 by incorporating a template-based, ambient, surfactantless, seedless, U-tube protocol in order to generate size and morphologically tailored, crystalline, phase-pure nanowires. The purity, composition, crystallinity, and intrinsic quality of these wires were systematically assessed using transmission electron microscopy （TEM）, high-resolution TEM （HRTEM）, scanning electron microscopy （SEM）, X-ray diffraction （XRD）, selected area electron diffraction （SAED）, energy dispersive analysis of X-rays （EDAX）, and high-resolution synchrotron XRD. From these techniques, we were able to determine that there is an absence of any obvious defects present in our wires, supporting the viability of our synthetic approach. Electrochemical analysis was also employed to assess their electrochemical activity. Although our nanowires do not contain any noticeable impurities, we attribute their less than optimal electrochemical rigor to differences in the chemical bonding between our LiFePO4 nanowires and their bulk-like counterparts. Specifically, we demonstrate for the first time experimentally that the Fe-O3 chemical bond plays an important role in determining the overall conductivity of the material, an assertion which is further supported by recent ＂first-principles＂ calculations. Nonetheless, our ambient, solution-based synthesis technique is capable of generating highly crystalline and phase-pure energy-storage-relevant nanowires that can be tailored so as to fabricate different sized materials of repro

关键词： ambient synthesis template synthesis cathode material lithium iron phosphate nanostructures

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Forest Resources Depletion: An Ecological Model for Biodiversity Preservation and Conservation in Cote D’Ivoire

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Open Journal of Ecology 2021年第12期11卷 870-890页

作者： Christian jonathan Anoma Kouassi Dilawar Khan Lutumba Suika Achille James Kehinde Omifolaji zhang Kebin School of Soil and Water Conservation Beijing Forestry University Beijing China School of Ecology and Nature Conservation Beijing Forestry University Beijing China Department of Forestry and Wildlife Management Federal University Dutse Nigeria

The biodiversity-rich primary forest of Cote d’Ivoire has been substantially converted into a mosaic of secondary forests, cash and lumber plantations, food crops, and timber plantations, food crops, and wasteland. Deforestation started even before independence but has increased dramatically in the last three decades, resulting in the loss of most of the country’s biodiversity. It is essential to have information about the condition of the country’s natural resources following many human pressures. This research aimed to examine the Cote d’Ivoire Phytogeographical zones to understand the state of the wood’s ad wildlife in 2020 about the anthropic pressure on the whole Ivorian land. The Land-Use Planner approach has been used as a tool for creating a model for preserving biodiversity. There are 15 endangered tree species recognized, five each phytogeographical zone. Buffaloes are seen and distributed in the West and north of Cote d’Ivoire, duikers are observed in nearly all phytogeographical zones, elephants are observed in the West and North. At the same time, harnessed guibs are observed and dispersed across the nation, according to the findings. In terms of endangered tree species, the most frequent endangered trees species in the country’s south are Strombosia pustulata (6.2%), Diospyros mannii (5.1%), Protomegabaria stapfiana (3.7%), Musanga cecropiodes (3.6%), and Xylopia quintasii (3.2%). In the Middle Tectona grandis accounts for (11.8%), Nesogordonia papaverifera accounts for (4.2%), Cedrela odorata accounts for (3.7%), and Gmelia Arborea accounts for (2.8%). In the North, Isoberlinia doka accounts for (10.3%), Upaca togoenisis accounts for 8.9%, Anogeisssus leicarpa accounts for (5.1%), Pterocarpus erinaceus accounts for (4.6%), and Pericopsis laxiflora accounts for (3.9%). In reforested woods, the volume of merchantable wood timber of the P1

关键词： Endemic Species Deforestation Cote d’Ivoire Land-Use Planner Phytography

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基于多传感器数据的新疆太阳辐射估算及其时空分布特征分析

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干旱区资源与环境 2015年第3期29卷 161-165页

作者：刘羽张显峰 jonathan Li 吕扬北京大学遥感与地理信息系统研究所北京100871 加拿大滑铁卢大学地理与环境管理学院

融合由Terra/MODIS与FY-3卫星数据反演得到的气溶胶产品,利用基于大气辐射传输原理建立的地面太阳直射辐射的反演模型,计算了2011年新疆地区的逐时太阳直射辐射分布状况。然后,选择乌鲁木齐、阿勒泰、喀什、和田与哈密5个气象站为代表,... 详细信息

融合由Terra/MODIS与FY-3卫星数据反演得到的气溶胶产品,利用基于大气辐射传输原理建立的地面太阳直射辐射的反演模型,计算了2011年新疆地区的逐时太阳直射辐射分布状况。然后,选择乌鲁木齐、阿勒泰、喀什、和田与哈密5个气象站为代表,分析了新疆地区太阳辐射资源的年度时空分布特征。结果表明:利用多遥感传感器数据能较好地反演新疆地区的太阳直射辐射,东疆的直射辐射最强,新疆北部次之,新疆西南部与中部相对较弱,且随季节变化特征明显,表现为夏>春>秋>冬,最高值一般出现在夏季的6月或7月,最低值为12月。

关键词：太阳能潜力 FY卫星直射辐射季节变化气溶胶

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基于曲率滤波和改进GMM的钢轨缺陷自动视觉检测方法

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仪器仪表学报 2018年第4期39卷 181-194页

作者：张辉金侠挺 Wu Q.M.jonathan 贺振东王耀南长沙理工大学电气与信息工程学院长沙410114 湖南大学电气与信息工程学院长沙410082 温莎大学温莎N983P4

针对传统钢轨检测技术的效率低下、精度不足、安全隐患等问题,提出了基于曲率滤波和改进高斯混合模型（GMM）的钢轨表面缺陷检测方法。首先,提出了基于垂直投影的区域定位算法和灰度对比算法,克服现场工况复杂、轨面反射不均、信道噪声... 详细信息

针对传统钢轨检测技术的效率低下、精度不足、安全隐患等问题,提出了基于曲率滤波和改进高斯混合模型（GMM）的钢轨表面缺陷检测方法。首先,提出了基于垂直投影的区域定位算法和灰度对比算法,克服现场工况复杂、轨面反射不均、信道噪声干扰的难题;考虑到图像信号受强工况噪声干扰,研究了具有隐式计算和曲面保持特性的曲率滤波法进行图像去噪;建立了基于马尔科夫随机场（MRF）的高斯混合模型完成表面缺陷的精确快速分割。最后,设计了＂区域定位-灰度均衡化-滤波-分割＂的实验流程,实验结果验证了算法的有效性,检测性能达到了精确度92.0%,相比其他方法更加精确、快速,具有更好的鲁棒性。

关键词：钢轨表面缺陷视觉检测曲率滤波马尔科夫随机场改进高斯混合模型

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Influence of Spatial Distribution on the Regeneration of <i>Piptadeniastrum africanum</i>and <i>Ocotea usambaernsis</i>in Kalikuku, Lubero, North Kivu, Democratic Republic of Congo

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Open Journal of Ecology 2021年第7期11卷 527-539页

作者： Lutumba Suika Achille Kebin zhang Kambale Muhesi Eloge Christian jonathan Anona Kouassi Mbangilwa Mukombe Michel College of Soil and Water Conservation and Desertification Combating Beijing Forestry University Beijing China Institut Supérieur d’Etudes Agronomiques Vétérinaires et Forestières de Butembo Butembo Democratic Republic of Congo Key Laboratory of Sustainable Forest Ecosystem Management Ministry of Education School of Forestry Northeast Forestry University Harbin China

The aim of our study is to highlight the spatial structure of the trees and to determine its influence on the natural regeneration of the Kalikuku dense forest, with a view of its optimal conservation and enhancement. Data collection was done by measuring diameter at breast height along 10 plots of 0.5 ha in size. In analyzing these data, the Dajoz test was used to determine the horizontal spatial distribution pattern of the two most abundant tree species in the forest (Piptadeniastrum africanum and Ocotea usambarensis). The χ2 test was used to compare the frequency distribution of diameter classes for the two species tested. To estimate the difference between the number of seedlings in aggregate versus non-aggregate areas, the Wilcoxon signed-rank test was used. In addition, the equability index was used to test the preponderance of proportions between diameter classes. Finally, the natural regeneration index was evaluated.

关键词： Spatial Distribution Natural Regeneration Seedlings Diameter Class

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Identification of coastal wetlands of international importance for waterbirds:a review of China Coastal Waterbird Surveys 2005–2013

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Chinese Birds 2015年第3期6卷 153-168页

作者： Qingquan Bai Jianzhong Chen Zhihong Chen Guotai Dong Jiangtian Dong Wenxiao Dong Vivian Wing Kan Fu Yongxiang Han Gang Lu Jing Li Yang Liu Zhi Lin Derong Meng jonathan Martinez Guanghui Ni Kai Shan Renjie Sun Suixing Tian Fengqin Wang Zhiwei Xu Yat-tung Yu Jin Yang Zhidong Yang Lin zhang Ming zhang Xiangwu Zeng Forestry Bureau of Dandong Tianjin Birdwatching Society Xiamen Birdwatching Society Shenzhen Birdwatching Society Management Office of Guangdong Neilingding–Futian National Nature Reserve Shanghai Huaxia Wildlife Travel Limited The Hong Kong Bird Watching Society Xugou Primary School Kadoorie Conservation China Kadoorie Farm & Botanic Garden Corporation Spoon-billed Sandpipers in China State Key Laboratory of Biocontrol and College of Ecology and Evolution Xiamen Costal Wetlands and Birds Research Center Department of Life Science Cangzhou Normal University 14 bis rue des Temples45240 La FertéSaint AubinFrance Fujian Birdwatching Society Management Office of Yellow River Delta National Nature Reserve Guangxi Mangrove Research Center Tianjin Natural History Museum Shanghai Wildbird Society Panjin Birdwatching Society Panjin Maternal and Child Care Service Centre Haifeng Nature Reserve

Background:China's coastal wetlands belong to some of the most threatened ecosystems *** loss and degradation of these wetlands seriously threaten waterbirds that depend on ***:The China Coastal Waterbird Census was organized by volunteer birdwatchers in China's coastal *** were surveyed synchronously once every month at 14 sites,as well as irregularly at a further 18 sites,between September 2005 and December ***:A total of 75 species of waterbirds met the 1 % population level Ramsar listing criterion at least once at one *** number of birds of the following species accounted for over 20 % of the total flyway populations at a single site:Mute Swan(Cygnus olor),Siberia Crane(Grus leucogeranus),Far Eastern Oystercatcher(Haematopus osculans),Bar-tailed Godwit(Limosa lapponica),Spotted Greenshank(Tringa guttifer),Great Knot(Calidris tenuirostris),Spoon-billed Sandpiper(Calidris pygmeus),Saunders' s Gull(Larus saundersi),Relict Gull(Larus relictus),Great Cormorant(Phalacrocorax carbo),Eurasian Spoonbill(Platalea leucorodia),Black-faced Spoonbill(Platalea minor) and Dalmatian Pelican(Pelecanus crispus).A total of 26 sites supported at least one species of which their number met the1 % ***-two species met the 1 % criterion in the Yellow River Delta,Shandong;29 at the Cangzhou coast,Hebei and 26 species at the Lianyungang coast,***:The results highlight the international importance of China's coastal wetlands for *** study also demonstrates that participation of local birdwatchers in waterbird surveys results in data that are invaluable not only for understanding the current status of waterbirds in China's coastal regions but also for waterbird conservation and management.

关键词： 1 % criterion Citizen science Coastal wetlands Ramsar site Waterbirds

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In vitro fermentation characteristics of human milk oligosaccharides by different dominating infant microbiota

In vitro fermentation characteristics of human milk oligosac...

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中国营养学会第十五届全国营养科学大会

作者： Shiqi Xu Hongye Li Feitong Liu Bin zhang jonathan Lane School of Food Science and Engineering South China University of Technology

This study investigated the in vitro fermentation profiles of human milk oligosaccharides(HMOs) by different dominating infant microbiota(***-, ***-and Bacteroides-dominated inocula). We sought to evaluate fecal microbiota composition of healthy infant donors in Guangzhou(including breast-feeding and formula-feeding). Further, we were expected to study in vitro fermentation outcomes of six commercial HMOs [i.e., 2 -fucosyllactose(2 -FL), 3-fucosyllactose(3-FL), 3 -sialyllactose(3 -SL), 6 -sialyllactose(6 -SL), lacto-Ntetraose(LNT) and lacto-N-neotetraose(LNnT)], fructo-oligosaccharide(FOS) and galacto-oligosaccharides(GOS) by using individual infant fecal inocula. Methods Nineteen healthy donors were selected at Guangzhou, China. Nine infants were qualified and enrolled in the experiment. Each 50 mg of carbohydrate sample was equivalently weighted into anaerobic tubes and fermented with fecal slurry at 37 °C water bath with gentle shaking for various time periods. Total gas production of each tube was measured by inserting the needle through rubber stopper with a graduated syringe. The concentration of short chain fatty acids(SCFAs) was determined by gas chromatography, and the concentration of organic acids(OAs) was determined by high performance liquid chromatography. DNA extraction from the fermented products was performed using the OMEGA Soil DNA Kit(M5635-02)(Omega Bio-Tek, Norcross, GA, USA), following the manufacturer s instruction. The nearly full-length bacterial 16 S rRNA from each purified DNA sample was performed to investigate microbiota composition. Results Fecal microbiota composition and microbiota classification It was noteworthy that three distinct clusters of infant gut microbiota were shown among nineteen infants. Three distinct groups were characterized by the bacteria abundance, denoted as B. longum-, B. breve-and Bacteroides-dominated inocula. Gas production In the early stage of fermentation(0-4 h), gas production of B. breve-dominat

关键词： human milk oligosaccharides fermentation characteristic infant gut microbiota

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Predisposing factors for positive D-Xylose breath test for evaluation of small intestinal bacterial overgrowth:A retrospective study of 932 patients

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World Journal of Gastroenterology 2015年第15期21卷 4574-4582页

作者： Richard A Schatz Qing zhang Nilesh Lodhia jonathan Shuster Phillip P Toskes Baharak Moshiree Department of Medicine Medical University of South Carolina Department of Gastroenterology University of Florida Gainesville Department of Gastroenterology Medical University of South Carolina Charleston Department of Health Outcomes and Policy University of Florida Gainesville Department of Gastroenterology University of Miami

AIM: To investigate, in the largest cohort to date, patient characteristics and associated risk factors for developing small intestinal bacterial overgrowth(SIBO) using the D-Xylose breath test(XBT).METHODS: We performed a retrospective crosssectional study to analyze patient characteristics who underwent the XBT for evaluation of SIBO. Diagnostic testing with the XBT was performed based on a clinical suspicion for SIBO in patients with symptoms of bloating, abdominal pain, abdominal distension, weight loss, diarrhea, and/or constipation. Consecutive electronicmedical records of 932 patients who completed the XBT at the University of Florida between 2005 and 2009 were reviewed. A two-way Analysis of Variance(ANOVA) was used to test for several associations including age, gender, and body mass index(BMI) with a +XBT. A two-way ANOVA was also performed to control for the differences and interaction with age and between genders. A similar analysis was repeated for BMI. Associations between medical conditions and prior surgical histories were conducted using the Mantel-Haenszel method for 2 by 2 contingency tables, stratified for gender. Reported odds ratio estimates reflect the odds of the prevalence of a condition within the +XBT group to that of the-XBT group. P values of less than 0.05(two-sided) were considered statistically ***: In the 932 consecutive eligible subjects studied, 513 had a positive XBT. A positive association was found between female gender and a positive XBT(P = 0.0025), and females with a positive test were, on average, greater than 5 years older than those with a negative test(P = 0.024). The mean BMI of positive XBT subjects was normal(24.5) and significantly lower than the subjects with a negative XBT(29.5)(P = 0.0050). A positive XBT was associated with gastroesophageal reflux disease(GERD)(OR = 1.35; 95%CI: 1.02-1.80, P = 0.04), peptic ulcer disease(PUD)(OR = 2.61; 95%CI: 1.48-4.59, P < 0.01), gastroparesis(GP)(OR = 2.04; 95%C

关键词： Intestine Small Irritable bowel syndrome Xylose Breath tests Proton pump inhibitors Gastroparesis Bacteria

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The miR319-Targeted GhTCP4 Promotes the Transition from Cell Elongation to Wall Thickening in Cotton Fiber

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Molecular Plant 2020年第7期13卷 1063-1077页

作者： Jun-Feng Cao Bo Zhao Chao-Chen Huang Zhi-Wen Chen Ting Zhao Hong-Ru Liu Guan-Jing Hu Xiao-Xia Shangguan Chun-Min Shan- Ling-Jian Wang Tian-Zhen zhang jonathan F.Wendel Xue-Ying Guan Xiao-Ya Chen National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and Ecology/CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai 200032China Plant Stress Biology Center Institute of Plant Physiology and Ecology/CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai 200032China University of Chinese Academy of Sciences Shanghai 200032China School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China Agronomy Department College of Agriculture and BiotechnologyZhejiang UniversityHangzhouZhejiang 310058China Department of Ecology Evolution and Organismal BiologyIowa State UniversityAmesIA 50011.USA Plant Science Research Center Shanghai Key Laboratory of Plant Functional Genomics and ResourcesShanghai Chenshan Botanical GardenShanghai 201602China

Plant cell growth involves a complex interplay among cell-wall expansion, biosynthesis, and, in specific tissues, secondary cell wall (SCW) deposition, yet the coordination of these processes remains elusive. Cotton fiber cells are developmentally synchronous, highly elongated, and contain nearly pure cellulose when mature. Here, we report that the transcription factor GhTCP4 plays an important role in balancing cotton fiber cell elongation and wall synthesis. During fiber development the expression of miR319 declines while GhTCP4 transcript levels increase, with high levels of the latter promoting SCW deposition. GhTCP4 interacts with a homeobox-containing factor, GhHOX3, and repressing its transcriptional activity. GhTCP4 and GhHOX3 function antagonistically to regulate cell elongation, thereby establishing temporal control of fiber cell transition to the SCW stage. We found that overexpression of GhTCP4A upregulated and accelerated activation of the SCW biosynthetic pathway in fiber cells, as revealed by transcriptome and promoter activity analyses, resulting in shorter fibers with varied lengths and thicker walls. In contrast, GhTCP4 downregulation led to slightly longer fibers and thinner cell walls. The GhHOX3–GhTCP4 complex may represent a general mechanism of cellular development in plants since both are conserved factors in many species, thus providing us a potential molecular tool for the design of fiber traits.

关键词： cell elongation secondary cell wall cotton fiber Gossypium hirsutum TCP microRNA

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