Effectively separating bastnaesite from calcium-bearing gangue minerals(particularly calcite)presents a formidable challenge,making the development of efficient collectors crucial.To achieve this,we have designed and ...Effectively separating bastnaesite from calcium-bearing gangue minerals(particularly calcite)presents a formidable challenge,making the development of efficient collectors crucial.To achieve this,we have designed and synthesized a novel,highly efficient,water-soluble cationic collector,N-dodecylisopropanolamine(NDIA),for use in the bastnaesite-calcite flotation process.Density functional theory(DFT)calculations identified the amine nitrogen atom in NDIA as the site most susceptible to electrophilic attack and electron loss.By introducing an OH group into the traditional collector dodecylamine(DDA)structure,NDIA provided additional adsorption sites,enabling synergistic adsorption on the surface of bastnaesite,thereby significantly enhancing both the floatability and selectivity of these minerals.The recovery of bastnaesite was 76.02%,while the calcite was 1.26%.The NDIA markedly affected the zeta potential of bastnaesite,while its impact on calcite was relatively minor.Detailed Fourier-transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS)results elucidated that the―NH―and―OH groups in NDIA anchored onto the bastnaesite surface through robust electrostatic and hydrogen bonding interactions,thereby enhancing bastnaesite's affinity for NDIA.Furthermore,in situ atomic force microscopy(AFM)provided conclusive evidence of NDIA aggregation on the bastnaesite surface,improving contact angle and hydrophobicity,and significantly boosting the flotation recovery of bastnaesite.展开更多
Revealing the localized corrosion process of Mg alloy is considered as one of the most significant ways for improving its corrosion resistance.The reliable monitor should be high distinguishability and real-time in li...Revealing the localized corrosion process of Mg alloy is considered as one of the most significant ways for improving its corrosion resistance.The reliable monitor should be high distinguishability and real-time in liquid environment.Herein,Mg-9Al-1Fe and Mg-9Al-1Fe-1Gd alloys were designed to highlight the impact of intermetallic on the corrosion behaviour.In-situ AFM with a special electrolyte circulation system and quasi-in-situ SEM observation were used to monitor the corrosion process of the designed alloys.SEM-EDS and TEM-SAED were applied to identify the intermetallic in the designed alloys,and their volta potentials were measured by SKPFM.According to the real-time and real-space in-situ AFM monitor,the corrosion process consisted of dissolution of anodicα-Mg phase,accumulation of corrosion products around cathodic phase and shedding of some fine cathodic phase.Then,the localized corrosion process of Mg alloy was revealed combined with the results of the monitor of corrosion process and Volta potential difference.展开更多
综述了基于原子力显微镜的红外光谱(Atomic force microscopy-based infrared spectroscopy,AFM-IR)的特点,测量和检测原理及其技术优势。AFM-IR是能在纳米尺度对不同材料进行表征的新兴技术,该技术可以以远低于常规光学衍射极限的分辨...综述了基于原子力显微镜的红外光谱(Atomic force microscopy-based infrared spectroscopy,AFM-IR)的特点,测量和检测原理及其技术优势。AFM-IR是能在纳米尺度对不同材料进行表征的新兴技术,该技术可以以远低于常规光学衍射极限的分辨率检测材料的化学成分,同时提供不同组分的分布图谱。AFM-IR的原理是利用原子力显微镜(AFM)悬臂梁的振动检测样本因吸收红外辐射脉冲产生的热膨胀,因此AFM-IR在继承了AFM的纳米级分辨率的基础上结合了红外光谱的化学分析能力,克服了二者原有的缺点并实现了优势互补。这项新技术在过去十多年备受关注并获得了长足的发展,因其操作简便、系统稳定、样品制备要求相对较低,以及与红外光谱直接相关而无需数学建模或额外数据后续处理,已被广泛用于材料科学、生命科学等诸多领域。展开更多
基金supported by the the National Key R&D Program of China(No.2021YFC2900800)National Natural Science Foundation of China(Nos.52425406,51874247,51922091,and 52204285)+4 种基金the Open Research Fund of State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization(No.CNMRCUKF2001)Science and Technology Major Project of Ordos City-Iconic Innovation Team and‘‘Rejuvenating Inner Mongolia through Science and Technology”(No.202204/2023)Yueqi Outstanding Scholar Award of CUMTB(No.202022)Funded by Open Foundation of State Key Laboratory of Mineral Processing(No.BGRIMM-KJSKL-2023-05)Fundamental Research Funds for the Central Universities(Ph.D.Top Innovative Talents Fund of CUMT BBJ2024048)。
文摘Effectively separating bastnaesite from calcium-bearing gangue minerals(particularly calcite)presents a formidable challenge,making the development of efficient collectors crucial.To achieve this,we have designed and synthesized a novel,highly efficient,water-soluble cationic collector,N-dodecylisopropanolamine(NDIA),for use in the bastnaesite-calcite flotation process.Density functional theory(DFT)calculations identified the amine nitrogen atom in NDIA as the site most susceptible to electrophilic attack and electron loss.By introducing an OH group into the traditional collector dodecylamine(DDA)structure,NDIA provided additional adsorption sites,enabling synergistic adsorption on the surface of bastnaesite,thereby significantly enhancing both the floatability and selectivity of these minerals.The recovery of bastnaesite was 76.02%,while the calcite was 1.26%.The NDIA markedly affected the zeta potential of bastnaesite,while its impact on calcite was relatively minor.Detailed Fourier-transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS)results elucidated that the―NH―and―OH groups in NDIA anchored onto the bastnaesite surface through robust electrostatic and hydrogen bonding interactions,thereby enhancing bastnaesite's affinity for NDIA.Furthermore,in situ atomic force microscopy(AFM)provided conclusive evidence of NDIA aggregation on the bastnaesite surface,improving contact angle and hydrophobicity,and significantly boosting the flotation recovery of bastnaesite.
基金support by the National Natural Science Foundation of China(51961026)the Interdisciplinary Innovation Fund of Nanchang University(Project No.2019-9166-27060003).
文摘Revealing the localized corrosion process of Mg alloy is considered as one of the most significant ways for improving its corrosion resistance.The reliable monitor should be high distinguishability and real-time in liquid environment.Herein,Mg-9Al-1Fe and Mg-9Al-1Fe-1Gd alloys were designed to highlight the impact of intermetallic on the corrosion behaviour.In-situ AFM with a special electrolyte circulation system and quasi-in-situ SEM observation were used to monitor the corrosion process of the designed alloys.SEM-EDS and TEM-SAED were applied to identify the intermetallic in the designed alloys,and their volta potentials were measured by SKPFM.According to the real-time and real-space in-situ AFM monitor,the corrosion process consisted of dissolution of anodicα-Mg phase,accumulation of corrosion products around cathodic phase and shedding of some fine cathodic phase.Then,the localized corrosion process of Mg alloy was revealed combined with the results of the monitor of corrosion process and Volta potential difference.
文摘综述了基于原子力显微镜的红外光谱(Atomic force microscopy-based infrared spectroscopy,AFM-IR)的特点,测量和检测原理及其技术优势。AFM-IR是能在纳米尺度对不同材料进行表征的新兴技术,该技术可以以远低于常规光学衍射极限的分辨率检测材料的化学成分,同时提供不同组分的分布图谱。AFM-IR的原理是利用原子力显微镜(AFM)悬臂梁的振动检测样本因吸收红外辐射脉冲产生的热膨胀,因此AFM-IR在继承了AFM的纳米级分辨率的基础上结合了红外光谱的化学分析能力,克服了二者原有的缺点并实现了优势互补。这项新技术在过去十多年备受关注并获得了长足的发展,因其操作简便、系统稳定、样品制备要求相对较低,以及与红外光谱直接相关而无需数学建模或额外数据后续处理,已被广泛用于材料科学、生命科学等诸多领域。