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growth behavior of the magnetite phase in the reduction of hematite via a fluidized bed

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International Journal of Minerals,Metallurgy and Materials 2019年第10期26卷 1231-1238页

作者： Jian-wen Yu Yue-xin Han Yan-jun Li Peng Gao School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&Metallurgy GroupBeijing 102628China

To understand the formation and growth mechanism of the magnetite phase during the fluidized reduction of hematite, a high-purity hematite ore was isothermally reduced using a 20vol% CO 80vol% CO2 gas mixture in a micro-fluidized bed to examine the process of the selective conversion of hematite to magnetite. The micro-structural characteristics of the magnetite phase were investigated using scanning electron microscopy (SEM) and the Brunauer, Emmett, and Teller (BET) method, and the thickness of the magnetite layer was measured and evaluated using statistical analysis. The experimental results showed that the fresh magnetite nuclei were dense needles of different lengths, and the original hematite grains became porous after complete reduction to the magnetite phase. The thickness of the mag- netite layer increased with an increase in reduction temperature and reduction time. The growth kinetics of the magnetite layer was investi- gated, and the value of the activation energy E was estimated to be 28.33 kJ/mol.

关键词： hematite ore fluidized bed suspension magnetization roasting magnetite growth kinetics

growth Defects in Langasite Crystals Observed with White Beam Synchrotron Radiation Topography

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Journal of Rare Earths 2006年第z1期24卷 159-161页

作者： Wang Xuping Wang Jiyang Hu Xiaobo Zhang Jianxiu Zhao Hongyang Huang Wanxia Zhu Peiping State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China Beijing Synchrotron Radiation Laboratory Institute of High Energy Physics Beijing 100039 China Beijing Synchrotron Radiation Laboratory Institute of High Energy Physics Beijing 100039 China

Langasite single crystal was grown by the Czochralski method and its perfection was assessed by white beam synchrotron radiation topography. It is found that the growth core and the growth striations are the primary growth defects and they show strong X-ray kinematical contrast in the topographs. Another typical defect in LGS crystal is dislocation. The formation mechanisms of these growth defects in LGS crystals were discussed.

关键词： Langasite (LGS crystal) growth striation growth core dislocation

growth and passivation of aluminum etch tunnels at on-off controlling direct current in 6 wt.% HCI solution

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Rare Metals 2008年第2期27卷 205-209页

作者： WANG Mei HE Yedong Beijing Key Laboratory for Corrosion Erosion and Surface Technique University of Science and Technology Beijing Beijing 100083 China

growth and passivation of tunnels within Al foil by on-off controlling DC etching in 6 wt.% HCI solution has been investigated. It was found that, in a given etchant solution at a special temperature, the longest tunnel length was only a function of the turn-on interval of DC. The potential of Al foil broke at on-off controlling DC by the result from anode polarization curves and potential-time （E-t） responding curves. When DC was switched on, the potential increased abruptly over pitting potential, leading to nucleation of pits at the surface and the growth of tunnels at special length. When DC was switched off, the potential decreased rapidly to a passive value, leading to stoppage of nucleation and death of tunnels. By this way, the longest tunnel length can be controlled and a non-piercing layer can be obtained. Hence, etching of Al foil at this current is beneficial for maintaining a good mechanical strength.

关键词： aluminum electrolytic capacitor tunnel length growth passivation on-off controlling current

growth responses of Picea mongolica seedlings to defoliation rate

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Journal of Environmental Sciences 2005年第2期17卷 232-236页

作者： ZOUChun-jing HANShi-jie QIShu-yan XUWen-duo LIDao-tang CollegeofLifeScience＆Biotechnology ShanghaiJiaotongUniversityShanghai200030China／／InstituteofAppliedEcologyChineseAcademyofSciencesShenyang110016China InstituteofAppliedEcology ChineseAcademyofSciencesShenyang110016China NormalCollege ShenyangUniversityShenyang110016China CollegeofLifeScience＆Biotechnology ShanghaiJiaotongUniversityShanghai200030China

Picea mongolica W. D. Xu. is an endemic species in China. The spruce forest is only found in semi-arid habitat in Inner Mongolia Autonomous Region of China. Based on the simulative defoliation experiment, it was proved that Picea mongolica seedlings had the compensatory and overcompensatory effects under the certain defoliation rate. The results of variance analysis on growth indexes showed that in PM Ⅰ(natural regeneration seedlings under Picea mongolica forest), the differences of H 1(height in June 23) and H 2(height in September 3) were extremely significant, and the difference of D(diameter at the breast height) were not significant. In PM Ⅱ(artificial regeneration seedlings under Betula platyphylla Suk. forest), the difference of H 1 was significant, the difference of H 2 was not significant, and the difference of D was extremely significant. The regression equations were established and the compensatory and overcompensatory points were obtained. In PM Ⅰ, the compensatory points of H 1, H 2, and D were 0.7628, 0.7436, 0.5725, and the overcompensatory points were 0.6056, 0.5802 and 0.2909 respectively. In PM Ⅱ, the compensatory points of H 1, H 2, and D are 0.5012, 0.3421, 0.2488, and the overcompensatory points are 0.4137, 0.2633 and 0.0747 respectively. These results suggested that the induction of compensatory growth mechanisms in spruce seedlings required a threshold level of defoliation, and the insects in Picea mongolica forest could be controlled in a certain degree.

关键词： Picea mongolica W. D. Xu. compensate overcompensate growth defoliation rate

growth of ZnO Single Crystal by Chemical Vapor Transport Method

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Journal of Rare Earths 2006年第z1期24卷 4-7页

作者： Zhao Youwen Dong Zhiyuan Wei Xuecheng Duan Manlong Li Jinmin Institute of Semiconductor Chinese Academy of Sciences Beijing 100083 China Institute of Semiconductor Chinese Academy of Sciences Beijing 100083 China Institute of Semiconductor Chinese Academy of Sciences Beijing 100083 China Institute of Semiconductor Chinese Academy of Sciences Beijing 100083 China Institute of Semiconductor Chinese Academy of Sciences Beijing 100083 China

ZnO crystals were grown by CVT method in closed quartz tube under seeded condition. Carbon was used as a transport agent to enhance the chemical transport of ZnO in the growth process. ZnO single crystals were grown by using GaN/sapphire and GaN/Si wafer as seeds. The property and crystal quality of the ZnO single crystals was studied by photoluminescence spectroscopy and X-ray diffraction technique.

关键词： zinc oxide chemical vapor transport single crystal growth

growth and Characterization of Perovskite K1-yLiyTa1-xNbxO3∶Ce

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Journal of Rare Earths 2006年第z1期24卷 261-263页

作者： Tian Hao He Chongjun Shen Yanqing Xin Jiangbo Zhou Zhongxiang Department of Physics Harbin Institute of Technology Harbin 150001 China Department of Physics Harbin Institute of Technology Harbin 150001 China Department of Physics Harbin Institute of Technology Harbin 150001 China Department of Physics Harbin Institute of Technology Harbin 150001 China Department of Physics Harbin Institute of Technology Harbin 150001 China

The grown Ce doped potassium lithium tantalite niobate (KLTN) crystals and characterize their physical properties were reported. The top seeded solution growth method was described. The specifics of a particular KLTN∶Ce growth were presented. X-ray diffraction spectra of paraelectric and ferroelectric KLTN crystals were illustrated. Dielectric and absorption studies on KLTN∶Ce were carried out compared with pure KLTN.

关键词： top seeded solution growth KLTN X-ray diffraction dielectric materials

growth, Proximate Composition and Pigment Production of Tetraselmis chuii Cultured with Aquaculture Wastewater

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Journal of Ocean University of China 2018年第3期17卷 641-646页

作者： KHATOON Helena HARIS Haris RAHMAN Norazira Abdu ZAKARIA Mimi Nadzirah BEGUM Hasina MIAN Sohel Institute of Tropical Aquaculture Universiti Malaysia Terengganu Department of Aquaculture Chittagong Veterinary and Animal Sciences University Department of Aquatic Bioscience Graduate School of Agricultural and Life Science The University of Tokyo School of Fisheries and Aquaculture Sciences Universiti Putra Malaysia Institute of Bioscience Universiti Putra Malaysia Department of Fisheries Biology & Genetics Sylhet Agricultural University

Microalgae are cultured commercially as healthy food, cosmetic products, food preservatives, and a source of valuable compounds. However, the high cost of commercial culture medium is one of the challenges to microalgal production. Therefore, it is essential to find an alternative cost-effective culture medium. Aquaculture wastewater is considered as a highly potential candidate due to its high nutrient content and large quantity generated from the rapid growth of aquaculture sector. In this study, Tetraselmis chuii cultured in different media with or without wastewater was evaluated for its growth, proximate composition and carotenoid production. The results showed that significantly(P growth(4.3 × 105 cells mL^(-1)) and protein(56.4% dry weight), lipid(44% dry weight) and carbohydrate(20% of dry weight) contents were found in T. chuii when they were cultured in the combination of both wastewater and Conway(wastewater + Conway) medium. However, carotenoid production of T. chuii was significantly increased(P growth and nutritional content of microalgae.

关键词： wastewater growth proximate composition Tetraselmis chuii

growth and Distribution of Amphioctopus fangsiao(d'Orbigny, 1839–1841) in Haizhou Bay, Yellow Sea

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Journal of Ocean University of China 2020年第5期19卷 1125-1132页

作者： PANG Yumeng TIAN Yongjun FU Caihong REN Yiping WAN Rong Fisheries College Ocean University of ChinaQingdao 266003China Frontiers Science Center for Deep Ocean Multispheres and Earth System(FDOMES) Ocean University of ChinaQingdao 266100China Laboratory for Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Fisheries and Oceans Canada Pacific Biological StationNanaimoBritish Columbia V9T 6N7Canada College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China

Octopus fisheries have prospered in many areas of the world ocean over the last six decades. Despite degradation and overexploitation of Chinese coastal ecosystems, octopus has become a stable Chinese domestic fishery species. Among the octopus species in the Bohai and Yellow, East and South China Seas, Amphioctopus fangsiao(d'Orbigny [in Férussac & d'Orbigny], 1839–1841) plays an increasingly important role both economically and ecologically. However, no systematic research has been conducted on its biology and population dynamics in the China Seas. In this study, we characterized the growth and distribution of A. fangsiao in Haizhou Bay, Yellow Sea based on four years of trawl survey data. As the results, A. fangsiao is characterized by allometric growth and an overall sex ratio of 0.97 with a slight male bias. Small octopus can be observed through a whole year, suggesting that A. fangsiao may have an extended or continuous spawning season. A. fangsiao may migrate short distances along with seasonal changes and coastal currents, considering they overwinter in the offshore water and spawn in the inshore water. In addition to fishing pressure, annual variations in the population structure and biomass appeared to be influenced by ambient water temperature. These results provide basic biological information for a better understanding of the population dynamics and the ecological importance of A. fangsiao.

关键词： Amphioctopus fangsiao cephalopod Haizhou Bay growth spatial distribution

growth units model of anion coordination-polyhedra and its application to crystal growth

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Science China(Technological Sciences) 2004年第2期47卷 191-202页

作者： ZHANG Xuehua LUO Haosu ZHONG Weizhuo Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 201800 China Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 201800 China Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 201800 China

growth units model of anion coordination-polyhedra ACP model emphasizes the influence of intrinsic structure of crstal upon the crystal growth and the importance of the external conditions on which crystals grow. The ACP model is used to analyze some problems in crystal growth, such as the formation of dendrite in the crystal structure, growth habit of polar crystal, and formation of allomerism and polymorphism.

关键词： crystal growth theory, growth-unit, morphology.