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Facile synthesis of yolk-shell Ni@void@SnO2（Ni3Sn2） ternary composites via galvanic replacement/Kirkendall effect and their enhanced microwave absorption properties

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Nano Research 2017年第1期10卷 331-343页

作者： Biao Zhao Xiaoqin Guo Wanyu Zhao Jiushuai Deng Bingbing Fan Gang Shao Zhongyi Bai Rui Zhang Provincial Key Laboratory of Aviation Materials and Application Technology Zhengzhou University of Aeronautics Zhengzhou 450046 China School of Mechatronics Engineering Zhengzhou University of Aeronautics Zhengzhou 450046 China School of Materials Science and Engineering Zhengzhou University Zhengzhou 450001 China State Key Laboratory of Complex Nonferrous Metal Resources Clean utilization Faculty of Land Resource Engineering Kunming University of Science and Technology Kunming 650093 China

Yolk-shell ternary composites composed of a Ni sphere core and a SnO2（Ni3Sn2） shell were successfully prepared by a facile two-step method. The size, morphology, microstructure, and phase purity of the resulting composites were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy （TEM）, high-resolution TEM, selected-area electron diffraction, and powder X-ray diffraction. The core sizes, interstitial void volumes, and constituents of the yolk-shell structures varied by varying the reaction time. A mechanism based on the time-dependent experiments was proposed for the formation of the yolk-shell structures. The yolk-shell structures were formed by a synergistic combination of an etching reaction, a galvanic replacement reaction, and the Kirkendall effect. The yolk-shell ternary SnO2 （Ni3Sn2）@Ni composites synthesized at a reaction time of 15 h showed excellent microwave absorption properties. The reflection loss was found to be as low as -43 dB at 6.1 GHz. The enhanced microwave absorption properties may be attributed to the good impedance match, multiple reflections, the scattering owing to the voids between the core and the shell, and the effective complementarities between the dielectric loss and the magnetic loss. Thus, the yolk-shell ternary composites are expected to be promising candidates for microwave absorption applications, lithium ion batteries, and photocatalysis.

关键词： yolk-shelLNi@void@SnO2(Ni3Sn2) galvanic replacement Kirkendall effect microwave absorption

Recovery of Zn, Pb, Fe and Si from a low-grade mining ore by sulfidation roasting-beneficiation-leaching processes

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Journal of Central South University 2020年第1期27卷 37-51页

作者： LAN Zhuo-yue LAI Zhen-ning ZHENG Yong-xing LV Jin-fang PANG Jie NING Ji-lai State Key Laboratory of Complex Nonferrous Metal Resources Clean utilization Kunming University of Science and TechnologyKunming 650093China Faculty of land Resource Engineering Kunming University of Science and TechnologyKunming 650093China

To recover Zn, Pb, Fe and Si from a low-grade mining ore in the Lanping basin, Yunnan Province, China, a novel technology using the roasting with pyrite and carbon followed by beneficiation and hydrochloric acid leaching was proposed. Firstly, several factors such as pyrite dosage, roasting temperature, carbon powder dosage, holding time and particle size affecting on the flotation performance of Zn(Pb) and magnetic separation performance of Fe were simultaneously examined and the optimum process parameters were determined. A flotation concentrate, containing 17.46% Zn and 3.93% Pb, was obtained, and the Zn and Pb recoveries were 86.04% and 69.08%, respectively. The obtained flotation tailing was concentrated by a low-intensity magnetic separator. The grade of iron increased from 5.45% to 43.45% and the recovery of iron reached 64.87%. Hydrochloric acid leaching was then carried out for the magnetic separation tailing and a raw quartz concentrate containing 81.05% SiO2 was obtained. To further interpret the sulfidation mechanism of smithsonite, surface morphology and component of the sample before and after reactions were characterized by XRD and EPMA-EDS. The aim was to achieve the comprehensive utilization of the low-grade mining ore.

关键词： low-grade mining ore comprehensive recovery sulfidation roasting flotation magnetic separation leaching

Reduction of Cr(Ⅵ) with a relative high concentration using different kinds of zero-valent iron powders: Focusing on effect of carbon content and structure on reducibility

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Journal of Central South University 2018年第9期25卷 2119-2130页

作者： LV Jin-fang TONG Xiong ZHENG Yong-xing XIE Xian HUANG Ling-yun Faculty of land Resource Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Complex Nonferrous Metal Resources Clean utilization(Kunming University of Science and Technology) Kunming 650093China

Reduction of Cr(VI)using zero-valent iron(ZVI)could not only decrease the amounts of chemicals used for reduction,but also decrease the discharge of *** order to find a desirable ZVI material,reduction of Cr(VI)with a relative high concentration using different kinds of ZVI powders(mainly carbon differences)including reduced Fe,grey cast iron,pig iron,nodular pig iron was carried *** such as ZVI dosage,type and size affecting on Cr(VI)reduction were firstly examined and grey cast iron was selected as a preferable reducing material,followed by pig ***,it was found that the parameters had significant influences on experimental ***,morphology and composition of the sample before and after reaction were characterized by SEM,EPMA and XPS analyses to disclose carbon effect on the *** order to further interpret reaction mechanism,different reaction models were *** was revealed that not only the carbon content could affect the Cr(VI)reduction,but also the carbon structure had an important effect on its reduction.

关键词： relative high concentration Cr(VI) reduction ZVI powder carbon content carbon structure

Combining nitrogen effects and metabolomics to reveal the response mechanisms to nitrogen stress and the potential for nitrogen reduction in maize

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Journal of Integrative Agriculture 2023年第9期22卷 2660-2672页

作者： LU Yan-li SONG Gui-pei WANG Yu-hong WANG Luo-bin XU Meng-ze ZHOU Li-ping WANG Lei State Key Laboratory of Efficient utilization of Arid and Semi-arid Arable land in Northern China/Key Laboratory of Plant Nutrition and Fertilizer Ministry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081P.R.China Tianjin Academy of Agricultural Sciences Tianjin 300384P.R.China

The physiological and metabolic differences in maize under different nitrogen(N)levels are the basis of reasonable N management,which is vital in improving fertilizer utilization and reducing environmental *** this paper,on the premise of defining the N fertilizer efficiency and yield under different long-term N fertilization treatments,the corresponding differential metabolites and their metabolic pathways were analyzed by untargeted metabolomics in maize.N stress,including deficiency and excess,affects the balance of carbon(C)metabolism and N metabolism by regulating C metabolites(sugar alcohols and tricarboxylic acid(TCA)cycle intermediates)and N metabolites(various amino acids and their derivatives).L-alanine,L-phenylalanine,L-histidine,and L-glutamine decreased under N deficiency,and L-valine,proline,and L-histidine increased under N *** addition to sugar alcohols and the above amino acids in C and N metabolism,differential secondary metabolites,flavonoids(e.g.,kaempferol,luteolin,rutin,and diosmetin),and hormones(e.g.,indoleacetic acid,trans-zeatin,and jasmonic acid)were initially considered as indicators for N stress diagnosis under this experimental *** study also indicated that the leaf metabolic levels of N2(120 kg ha–1 N)and N3(180 kg ha–1 N)were similar,consistent with the differences in their physiological indexes and yields over 12 *** study verified the feasibility of reducing N fertilization from 180 kg ha–1(locally recommended)to 120 kg ha–1 at the metabolic level,which provided a mechanistic basis for reducing N fertilization without reducing yield,further improving the N utilization rate and protecting the ecological environment.

关键词： long-term experiment nitrogen deficiency nitrogen excess metabolites UPLC-QTOF

Radial velocity of ocean surface current estimated from SAR Doppler frequency measurements—a case study of Kuroshio in the East China Sea

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Acta Oceanologica Sinica 2021年第12期40卷 135-147页

作者： Lihua Wang Benwei Shi Yunxuan Zhou Hui Sheng Yanghua Gao Li Fan Ziheng Yang Department of Geography and Spatial Information Techniques/Center for land and Marine Spatial utilization and Governance Research Ningbo UniversityNingbo 315211China State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200062China Chongqing Institute of Meteorological Sciences Chongqing 401147China College of Resources and Environment Chengdu University of Information TechnologyChengdu 610225China

Ocean currents are a key element in ocean processes and in meteorology,affecting material transport and modulating climate change *** Doppler frequency shift information of the synthetic aperture radar(SAR)echo signal can reflect the dynamic characteristics of the sea surface,and has become an essential sea surface dynamic remote sensing *** have verified that the instantaneous Doppler frequency shift can realize the SAR detection of the sea surface ***,the validation of SAR-derived ocean current data and a thorough analysis of the errors associated with them remain *** this study,we derive high spatial resolution flow measurements for the Kuroshio in the East China Sea from SAR data using a theoretical model of shifts in Doppler frequency driven by ocean surface *** ocean multi observation(MOB)products and global surface Lagrangian drifter(GLD)data are used to validate the Kuroshio flow retrieved from the SAR *** show that the central flow velocity for the Kuroshio derived from the SAR is 0.4–1.5 m/*** error distribution between SAR ocean currents and MOB products is an approximate standard normal distribution,with the 90%confidence interval concentrated between–0.1 m/s and 0.1 m/*** analysis of SAR ocean current and GLD products,the correlation coefficient is 0.803,which shows to be significant at a confidence level of 99%.The cross-validation of different ocean current dataset illustrate that the SAR radial current captures the positions and dynamics of the Kuroshio central flow and the Kuroshio Counter Current,and has the capability to monitor current velocity over a wide range of values.

关键词： Doppler frequency radial velocity ocean current SAR Kuroshio

The RING zinc finger protein LbRZF1 promotes salt gland development and salt tolerance in Limonium bicolor

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Journal of Integrative Plant Biology 2024年第4期66卷 787-809页

作者： Zongran Yang Ziwei Zhang Ziqi Qiao Xueying Guo Yixuan Wen Yingxue Zhou Chunliang Yao Hai Fan Baoshan Wang Guoliang Han Shandong Provincial Key Laboratory of Plant Stress College of Life SciencesShandong Normal UniversityJi'nan 250014China National Center of Technology Innovation for Comprehensive utilization of Saline-Alkali land Agricultural High-tech Industrial Demonstration Area of the Yellow River Delta of Shandong ProvinceDongying 257000China Dongying Institute Shandong Normal UniversityDongying 257000China

The recretohalophyte Limonium bicolor thrives in high-salinity environments because salt glands on the above-ground parts of the plant help to expel excess ***,we characterize a nucleus-localized C3HC4(RING-HC)-type zinc finger protein of *** named RING ZINC FINGER PROTEIN 1(LbRZF1).LbRZF1 was expressed in salt glands and in response to NaCl ***1 showed no E3 ubiquitin ligase *** phenotypes of overexpression and knockout lines for LbRZF1 indicated that LbRZF1 positively regulated salt gland development and salt tolerance in ***1 mutants had fewer salt glands and secreted less salt than did the wild-type,whereas LbRZF1-overexpressing lines had opposite phenotypes,in keeping with the overall salt tolerance of these plants.A yeast two-hybrid screen revealed that LbRZF1 interacted with LbCATALASE2(LbCAT2)and the transcription factor LbMYB113,leading to their *** of LbCAT2 or LbMYB113 decreased salt gland density and salt *** heterologous expression of LbRZF1 in Arabidopsis thaliana conferred salt tolerance to this *** also identified the transcription factor LbMYB48 as an upstream regulator of LbRZF1 *** study of LbRZF1 in the regulation network of salt gland development also provides a good foundation for transforming crops and improving their salt resistance.

关键词： LbRZF1 Limonium bicolor molecular mechanism salt gland development salt tolerance

Nanoscale Pore Characteristics of the Upper Permian Mudrocks from a Transitional Environment in and around Eastern Sichuan Basin, China

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Acta Geologica Sinica(English Edition) 2019年第4期93卷 1025-1046页

作者： CAO Taotao LIU Guangxiang LIU Hu DENG Mo HAN Yuanhong HUANG Yanran Andrew S.HURSTHOUSE Hunan Provincial Key Laboratory of Shale Gas Resource utilization Hunan University of Science and TechnologyXiangtanHunan 411201China Department of Geology Hunan University of Science and TechnologyXiangtanHunan 411201China Wuxi Research Institute of Petroleum Geology Petroleum Exploration and Production Research InstituteSINOPECWuxiJiangsu 214126China Sichuan Key Laboratory of Shale Gas Evaluation and Exploration Chengdu 600091China Key Laboratory of Coal Resources Exploration and Comprehensive utilization Ministry of Land and ResourcesXi’an 710021China School of Science and Sport University of the West of ScotlandPaisley P A12BEUK

Nanoscale pore characteristics of the Upper Permian Longtan transitional mudrocks and their equivalent strata Wujiaping Formation marine mudrocks in and around the eastern Sichuan Basin was investigated using field emission scanning electron microscopy(FE-SEM)and low-pressure N2 adsorption *** results indicate that the Upper Permian mudrock is at a mature stage with total organic carbon(TOC)values ranging between 0.47%and 12.3%.The Longtan mudrocks mainly contain vitrinite,and their mineral composition is primarily *** contrast,the Wujiaping mudrocks are dominated by sapropelinite and solid bitumen,and their mineral compositions are mainly quartz and a notably high amount of *** FE-SEM reveals that clay mineral pores and microcracks are the common pore types in the Longtan *** specific surface area and pore volume depend on the clay content but are negatively correlated with the *** generation of nanometer pores in the Longtan mudrocks is caused by high clay mineral ***,the Wujiaping mudrock mainly contains OM pores,and the pore parameters are positively correlated with the *** OM pore development exhibits remarkable differences in the Longtan and Wujiaping mudrocks,which might be related to their sedimentary facies and maceral *** and inertinite appear as discrete particles in these mudrocks and cannot generate pores during thermal *** often contains many secondary pores,and solid bitumen with large particles,usually with several pores,is not the major contributor to the pore system of the investigated mudrock.

关键词： nanoscale pore characteristics FE-SEM low-pressure N2 adsorption transitional mudrock Longtan/Wujiaping Formation eastern Sichuan Basin

Preparation and interface state of phosphate tailing-based geopolymers

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Journal of Central South University 2024年第6期31卷 1900-1914页

作者： ZHANG Shou-xun XIE Xian XIE Rui-qi TONG Xiong WU Yu-yao LI Jia-wen LI Yue Faculty of land Resource Engineering Kunming University of Science and TechnologyKunming 650093China National&Regional Engineering Research Center for Green Comprehensive utilization of Gangue Resources from Metal Mine Kunming 650093China

The long-term storage of phosphate tailings will occupy a large amount of land,pollute soil and groundwater,thus,it is crucial to achieve the harmless disposal of phosphate *** this study,high-performance geopolymers with compressive strength of 38.8 MPa were prepared by using phosphate tailings as the main raw material,fly ash as the active silicon-aluminum material,and water glass as the alkaline *** solid content of phosphate tailings and fly ash was 60% and 40%,respectively,and the water-cement ratio was *** results of XRD,FTIR,SEM-EDS and XPS show that the reactivity of phosphate tailings with alkaline activator is weak,and the silicon-aluminum material can react with alkaline activator to form zeolite and gel,and encapsulate/cover the phosphate tailings to form a dense phosphate tailings-based *** the formation of geopolymers,part of the aluminum-oxygen tetrahedron replaced the silicon-oxygen tetrahedron,causing the polycondensation reaction between geopolymers and increasing the strength of *** leaching toxicity test results show that the geopolymer has a good solid sealing effect on heavy metal *** preparation of geopolymer from phosphate tailings is an important way to alleviate the storage pressure and realize the resource utilization of phosphate tailings.

关键词： phosphate tailing geopolymer interface state toxicity leaching

Adsorption behavior and mechanism of copper ions in the sulfidization flotation of malachite

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International Journal of Mining Science and Technology 2022年第4期32卷 897-906页

作者： Han Wang Shuming Wen Guang Han Yongxin He Qicheng Feng State Key Laboratory of Complex Nonferrous Metal Resources Clean utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China State Key Laboratory of Mineral Processing Beijing 100160China Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Mineral Resources Kunming University of Science and TechnologyKunming 650093China Inter Mongolia Xingye Mining Company Limited Chifeng 024028China

Malachite is one of the main minerals used for the industrial enrichment and recovery of copper oxide resources, and copper ions are unavoidable metal ions in the flotation pulp. The microflotation, contact angle, and adsorption experiments indicated that pretreatment with an appropriate concentration of copper ions could improve the malachite recovery, and the addition of excess copper ions reduced the hydrophobicity of the malachite surface. The results of zeta potential tests indicated that sodium sulfide and butyl xanthate were also adsorbed on the surface of malachite pretreated with copper ions. X-ray photoelectron spectroscopy(XPS) results indicated that —Cu—O and —Cu—OH bonds were formed on the surface of the samples. After pretreatment with an appropriate concentration of copper ions, the number of —OH groups on the mineral surface decreased, whereas the number of Cu—S groups on the mineral surface increased, which was conducive to the sulfidization of malachite. After adding a high concentration of copper ions, the —OH groups on the mineral surface increased, whereas the number of Cu—S groups decreased, which had an adverse effect on the sulfidization flotation of malachite. Time-of-flight secondary ion mass spectrometry showed that pretreatment with copper ions resulted in a thicker sulfidization layer on the mineral surface.

关键词： Malachite Sulfidization flotation Copper ions Adsorption