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Adsorption of fluoride on clay minerals and their mechanisms using X-ray photoelectron spectroscopy

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Frontiers of Environmental Science & Engineering 2011年第2期5卷 212-226页

作者： junyi du Daishe WU Huayun XIAO Ping LI Department of Environmental Science and Engineering Nanchang UniversityNanchang 330031China

This research investigates the adsorptionmechanisms of fluoride(F)on four clay minerals(kaolinite,montmorillonite,chlorite,and illite)underdifferent F^(-)concentrations and reaction times by probingtheir fluoride superficial layer binding energies and elementcompositions using X-ray photoelectron spectroscopy(XPS).At high F^(-)concentrations(C_(0)=5-1000 mg·L^(-1)),the amount of F^(-)adsorbed(Q_(F)),amount of hydroxidereleased by clay minerals,solution F^(-)concentration,andthe pH increase with increasing C_(0).The increases areremarkable at C_(0)>50 mg·L^(-1).The QF increases significantlyby continuously modifying the pH *** C_(0)duce F^(-)*** the C_(0)increases,F^(-),along with other cations,is adsorbed toform a quasi-cryolite *** C_(0)>100 mg·L^(-1),newminerals precipitate and the product depends on the criticalAl^(3+)***[Al^(3+)]>10^(-11.94)mol·L^(-1),cryoliteforms,while at[Al^(3+)]<10^(-11.94)mol·L^(-1),AlF_(3) is *** low C_(0)(0.3-1.5 mg·L^(-1)),proton transfer occurs,andthe F^(-)adsorption capabilities of the clay minerals increasewith time.

关键词： clay mineral fluoride(F) adsorption mechanism X-ray photoelectron spectroscopy(XPS)

A novel manganese(Ⅲ)-peroxo complex bearing a proline-derived pentadentate aminobenzimidazole ligand

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Chinese Chemical Letters 2018年第12期29卷 1869-1871页

作者： junyi du Chengxia Miao Chungu Xia Wei Sun State Key Laboratory for Oxo Synthesis and Selective Oxidation Suzhou Research Institute of LICPLanzhou Institute of Chemical Physics(LICP)Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

Manganese(Ⅲ)-peroxo complexes are invoked as key intermediates in the enzymatic cycles of Mncontaining enzymes, and the synthesis of reactive manganese(Ⅲ)-peroxo complexes with rationally designed ligand has been of great interest in the communities of bioinorganic and biomimetic ***, we designed a novel pentadentate aminobenzimidazole ligand and obtained its manganese(Ⅱ)complex, which was successfully applied in the synthesis of a reactive manganese(Ⅲ)-peroxo complex by treatment with hydrogen peroxide in the presence of triethylamine. The manganese(Ⅲ)-peroxo complex was well characterized with various spectroscopic techniques, including ultraviolet-visible(UV-vis)spectrophotometry, coldspray ionization time-of-flight mass spectrometry(CSI-TOF MS), and continuous wave electron paramagnetic resonance(CW-EPR) spectroscopy. Besides, its reactivity in aldehyde deformylation was investigated, demonstrating second-order kinetics in the reaction with 2-phenylpropionaldehyde and affording acetophenone as the sole product.

关键词： Enzyme models Manganese Manganese(Ⅲ)-peroxo complex Aldehyde deformylation Kinetics

A Novel Analytical Method of 1‑(3‑Trifluoromethylphenyl)piperazine and 1‑(3‑Chlorophenyl)piperazine in Fluids of Drug Addicts Using Liquid‑liquid Extraction–gas Chromatographic/Nitrogen–phosphorous Detection

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Journal of Forensic Science and Medicine 2017年第4期3卷 181-190页

作者： Jing Chang Bin Hao junyi du Hong Zhou Hongxia Hao Institute of Forensic Science Ministry of Public SecurityChina University of Political Science and LawMinistry of EducationBeijing100088China Collaborative Innovation Center of Judicial Civilization China University of Political Science and LawMinistry of EducationBeijing100088China Key Laboratory of Evidence Science China University of Political Science and LawMinistry of EducationBeijing100088China

In accordance with the research specifications and guidelines in China,we developed a novel experimental method to detect new piperazine‑type drugs,such as 1‑(3‑trifluoromethylphenyl)piperazine and 1‑(3‑chlorophenyl)*** this study,a new pretreatment method and gas chromatography(GC)/nitrogen–phosphorus detector detection technique were used to characterize these two kinds of drugs in urine and blood *** the purpose of isolation of these trace drugs from the samples,liquid‑liquid extraction/solid‑phase extraction was modified and validated for this specific *** pretreatment method presented in this paper has many advantages,such as high recovery rate,high extraction efficiency,high detection sensitivity,low limit of detection,and simple *** GC/NPD instrument is popular in most laboratories because it can meet the routine requirements of forensic *** these aspects make this combination of sample pretreatment and GC/NPD technique the most suitable choice for drug detection in biological samples.

关键词： 1‑(3‑trifluoromethylphenyl)piperazine 1‑(3‑chlorophenyl)piperazine biological fluids forensic drug gas chromatography/nitrogen-phosphorus detector piperazine derivatives toxicology tests

A highly accessible copper single-atom catalyst for wound antibacterial application

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Nano Research 2021年第12期14卷 4808-4813页

作者： Yue Zhao Yunpeng Yu Feng Gao Zhiyuan Wang Wenxing Chen Cai Chen Jia Yang Yancai Yao junyi du Chao Zhao Yuen Wu Department of Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleCollaborative Innovation Center of Chemistry for Energy Materials(iChEM)University of Science and Technology of ChinaHefei230026China Dalian National Laboratory for Clean Energy Dalian116023China Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing100081China College of Chemistry and Chemical Engineering Southwest Petroleum UniversityChengdu610500China

Bacterial infection arised from multipathogenic bacteria is a tricky issue that attracts worldwide *** this paper,a highly accessible copper single-atom catalyst(Cu SAC)supported by biocompatible N-doped mesoporous carbon nanospheres was synthesized with the emulsion-template *** tightly anchored copper single-atom of the catalyst could effectively transform O_(2) into O_(2)−•under ambient conditions by the ultra-large pore size(~23.80 nm)and small particle size(~97.71 nm).due to multiple synergistically oxidative damages to biomolecules,the Cu SAC could be employed to eliminate different bacteria in vitro without the generation of multidrug resistance(MDR).Moreover,the Cu SAC could also promote wound healing in vivo by eradicating the propagation of bacteria at *** is envisioned that the Cu SAC with superior antibacterial performance could be applied in the treatment of related bacterial infection in future.

关键词： copper single-atom catalyst mesoporous carbon nanospheres catalytic transformation of oxygen oxidative stress bacterial infection healing

Simultaneous diffusion of cation and anion to access N,S cocoordinated Bi-sites for enhanced CO_(2) electroreduction

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Nano Research 2021年第8期14卷 2790-2796页

作者： Zhiyuan Wang Chun Wang Yidong Hu Shuai Yang Jia Yang Wenxing Chen Huang Zhou Fangyao Zhou Lingxiao Wang junyi du Yafei Li Yuen Wu School of Chemistry and Materials Science Hefei National Laboratory for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Jiangsu Collaborative Innovation Centre of Biomedical Functional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China Dalian National Laboratory for Clean Energy Dalian 116023China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201210China Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid MaterialsMinistry of EducationAnhui Graphene Engineering LaboratoryAnhui UniversityHefei 230601China

Developing highly active single-atom sites catalysts for electrochemical reduction of CO_(2) is an effective and environmental-friendly strategy to promote carbon-neutral energy cycle and ameliorate global climate ***,we develop an atomically dispersed N,S co-coordinated bismuth atom sites catalyst(Bi-SAs-NS/C)via a cation and anion simultaneous diffusion strategy for electrocatalytic CO_(2) *** this strategy,the bonded Bi cation and S anion are simultaneously diffused into the nitrogen-doped carbon layer in the form of *** Bi is captured by the abundant N-rich vacancies and S is bonded with *** at high temperature,formed the N,S co-coordinated Bi *** from the simultaneous diffusion of Bi and S,different electronegative N and S can be effectively co-coordinated with Bi,forming the uniform Bi-N_(3)S/C *** ***-SAs-NS/C exhibits a high selectivity towards CO with over 88%Faradaic efficiency in a wide potential range,and achieves a maximum FE_(CO)of 98.3%at-0.8 V *** with a current density of 10.24 mA·cm^(-2),which can keep constant with negligible degradation in 24 h continuous *** results and theoretical calculations reveal that the significantly improved catalytic performance of Bi-SAs-NS/C than Bi-SAs-N/C is ascribed to the replacement of one coordinated-N with low electronegative S in Bi-N_(4)C center,which can greatly reduce the energy barrier of the intermediate formation in rate-limiting step and increase the reaction *** work provides an effective strategy for rationally designing highly active single-atom sites;catalysts for efficient electrocatalysis with optimized electronic structure.

关键词： S,N-co-doped carbon nanotube single bismuth sites electronic structure modulation electrochemical CO_(2)reduction

大型3.5%Ni型低温超纯净钢锻件的工艺与性能

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压力容器 2022年第11期39卷 1-8页

作者：杜军毅二重(德阳)重型装备有限公司四川德阳618000

为实现-100℃低温厚壁容器国产化,制造出满足-100℃低温工作条件下使用的大型、厚壁钢锻件,投制了1支69 t钢包精炼、真空除气+真空浇注钢锭,锻透压实后,从锻件取样进行了3.5%Ni型低温大锻件用钢的CCT曲线、临界点测定,以及热处理工艺参... 详细信息

为实现-100℃低温厚壁容器国产化,制造出满足-100℃低温工作条件下使用的大型、厚壁钢锻件,投制了1支69 t钢包精炼、真空除气+真空浇注钢锭,锻透压实后,从锻件取样进行了3.5%Ni型低温大锻件用钢的CCT曲线、临界点测定,以及热处理工艺参数研究。在大量的工艺试验的基础上,确定出3.5%Ni钢锻件最佳的淬火温度为820~890℃,最佳回火参数P值介于18.4~19.4之间。同时,该钢种在640℃以下具有较高的回火稳定性,当回火温度达到670℃以上时,可能使材料的韧性恶化。经69 t试验筒体制造工艺实施、解剖试验以及后续的产品验证证明,所采用的工艺方法是非常有效的,各项理化性能指标完全满足-100℃低温厚壁容器的质量要求。

关键词： 3.5%Ni 低温厚壁容器锻件工艺性能

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单核铁-氧和锰-氧加合物研究进展

化学学报 2018年第5期76卷 329-346页

作者：杜俊毅夏春谷孙伟中国科学院兰州化学物理研究所羰基合成与选择氧化国家重点实验室兰州化学物理研究所苏州研究院中国科学院大学

生物体系中,金属酶活化氧气进而参与新陈代谢相关的各种氧化反应,可高效实现有机化合物氧化反应.因此,揭示金属酶的循环机理,对发展清洁高效的催化氧化反应具有重要的指导意义.金属酶的循环过程通常会形成一系列的金属-氧加合物,如金属... 详细信息

生物体系中,金属酶活化氧气进而参与新陈代谢相关的各种氧化反应,可高效实现有机化合物氧化反应.因此,揭示金属酶的循环机理,对发展清洁高效的催化氧化反应具有重要的指导意义.金属酶的循环过程通常会形成一系列的金属-氧加合物,如金属超氧、过氧、过氧化氢、氧及羟基等物种.由于生物体的酶循环过程十分复杂,所形成的高活性的金属-氧加合物极难捕捉和表征.为此,化学家开展了生物酶的仿生模拟研究,即用化学的方法仿照酶的活性位点构建具有类似配位环境的金属中心,获得人工合成的各种金属-氧加合物,进而了解其结构与活性.本文以近年来单核铁-氧和锰-氧加合物取得重要进展为背景,举例说明金属酶活化氧气所涉及的金属-氧加合物,并重点从结构及活性等方面总结了模拟酶的金属-氧加合物的研究进展.

关键词：金属-氧加合物金属酶模拟酶 C—H键活化氧气活化

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基于最佳采样点的GMSK相干接收算法

系统工程与电子技术 2024年第9期46卷 3239-3245页

作者：孙岩博杜俊逸肖磊李根中国电子科技集团公司第十研究所四川成都610036 电子科技大学自动化工程学院四川成都611731

针对高斯滤波最小频移键控(Gaussian-filtered minimum shift keying,GMSK)相位连续性导致相位估计存在模糊度问题,提出一种基于最佳采样点的GMSK相干接收算法。发射端通过构造预编码方式对原始消息编码后调制,以实现符号间的相位解耦,... 详细信息

针对高斯滤波最小频移键控(Gaussian-filtered minimum shift keying,GMSK)相位连续性导致相位估计存在模糊度问题,提出一种基于最佳采样点的GMSK相干接收算法。发射端通过构造预编码方式对原始消息编码后调制,以实现符号间的相位解耦,接收端在码间串扰最小时刻实现最佳采样点抽取,将GMSK转变成类偏移四相相移键控(offset quadrature phase shift keying,OQPSK)调制,有效避免未知数据段对后续同步段引入模糊初相而导致多普勒相位和频率无法准确估计的问题,最后提出基于最佳采样点的GMSK相干解调算法,实现低复杂度的可靠接收。仿真结果表明,所提算法多普勒频率估计范围大且估计精度高,同时与最佳解调接收机相比,所提算法解调复杂度低且解调性能损失小。

关键词：高斯滤波最小频移键控最佳采样多普勒相位估计相干解调

益生菌对非酒精性脂肪性肝病的治疗及对肠功能的影响

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中国微生态学杂志 2023年第7期35卷 821-825页

作者：杜君义梅璐于泳郑州大学第五附属医院消化内科河南郑州450014

目的探讨双歧杆菌三联活菌对非酒精性脂肪性肝病患者的临床疗效及对小肠细菌过度生长、肠屏障功能的影响。方法选取180例诊断为非酒精性脂肪性肝病的患者,将其随机分成对照组(90例)和治疗组(90例)。对照组患者在健康宣教、运动指导、... 详细信息

目的探讨双歧杆菌三联活菌对非酒精性脂肪性肝病患者的临床疗效及对小肠细菌过度生长、肠屏障功能的影响。方法选取180例诊断为非酒精性脂肪性肝病的患者,将其随机分成对照组(90例)和治疗组(90例)。对照组患者在健康宣教、运动指导、饮食控制的基础上给予多烯磷脂酰胆碱治疗,治疗组患者在对照组的基础上加用双歧杆菌三联活菌治疗。在治疗前及治疗后分别检测两组患者的肝功能、空腹血糖、血脂、肠黏膜屏障功能、氢呼气试验等指标,观察变化并评估疗效。结果治疗前两组患者的肝功能、血脂、空腹血糖、小肠细菌过度生长阳性率、肠屏障功能差异均无统计学意义(均P>0.05)。治疗8周后,两组患者天门冬氨酸氨基转移酶、丙氨酸氨基转移酶、甘油三酯、总胆固醇、低密度脂蛋白、空腹血糖、D-乳酸、二胺氧化酶、血清内毒素水平均降低(均P0.05)。结论对非酒精性脂肪性肝病的治疗,常规治疗联合双歧杆菌三联活菌可抑制患者小肠细菌过度生长,改善肠黏膜屏障功能,改善患者的肝功能及血脂、血糖代谢情况。

关键词：非酒精性脂肪性肝病双歧杆菌三联活菌小肠细菌过度生长肠黏膜屏障功能临床疗效