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Photoreductive Dissolution of Schwertmannite with Incorporated As(Ⅴ) Induced by Oxalate and the Mobilization of As(Ⅴ)

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Transactions of Tianjin University 2019年第3期25卷 258-265页

作者： Zhaoyang Ji Haitao Ren shaoyi jia Songhai Wu School of Chemical Engineering and Technology Tianjin University State Key Laboratory of Separation Membranes and Membrane Processes School of Textiles Tianjin Polytechnic University

Schwertmannite(Sh), a poorly crystalline iron(hydr)oxide that usually appears in acid mine drainage, plays a significant role in the immobilization of As(V). In this study, the effects of UV irradiation and oxalate on the dissolution of Sh with structurally incorporated As(V) [Sh-As(V)] and the subsequent mobilization of As(V) were investigated at pH 3.0. In the dark, more total dissolved Fe was produced(the maximum value was 33.2 mg/L) in the suspensions of Sh-As(V) with oxalate than in those without oxalate. UV irradiation slightly enhanced the mobilization of As(V) for the system of Sh-As(V)-1 and Sh-As(V)-2 in the absence of oxalate compared with that in the dark. However, in the presence of oxalate, UV irradiation caused the concentration of mobilized As(V) to decline by 630-875% compared with that in the dark. This study enhanced our understanding of the mobilization of As(V) and demonstrated that UV irradiation could contribute to the immobilization of As(V) on Sh in aqueous environments containing oxalate.

关键词： Schwertmannite Photoreductive dissolution Oxalate As(Ⅴ) Mobilization

Oxidation Characteristics of the Reactivity Between Pyrite and Aqueous Arsenate

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Transactions of Tianjin University 2019年第4期25卷 371-380页

作者： Yongling Liu Songhai Wu shaoyi jia Zongsheng Liang Xu Han School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Key Lab of Indoor Air Environment Quality Control School of Environmental Science and EngineeringTianjin UniversityTianjin 300350China

Natural pyrites contain high levels of adsorbed and structurally incorporated arsenic(As),which may simultaneously result in the release of As and affect the oxidation process of ***,the oxidation and electrochemical behaviors of As on the oxidation reactivity of pyrites are still not *** this study,pyrite was prepared by a hydrothermal method and applied to study the oxidation mechanism between pyrite and aqueous *** of X-ray diffraction,X-ray photoelectron spectroscopy,and scanning electron microscopy demonstrate that the as-prepared sample is an octahedron-like pyrite with high purity and *** interaction between As(V)and pyrite as well as the electrochemical behaviors of pyrite oxidation in the presence of aqueous arsenate were investigated under acidic conditions by an ion analysis method,cyclic voltammetry(CV),Tafel,and electrochemical impedance spectroscopy(EIS).The results of the chemical reaction indicate that electrons are transferred from S 22-to dissolved oxygen with the formation of SO 42-in the initial As(V)concentration range of 0–0.3 mmol/*** the initial As(V)concentration range of 0.4–1.2 mmol/L,electrons are transferred from S 22-to As(V)with the formation of elemental S 0 and As(III).The CV,the Tafel plot and EIS analyses indicate that aqueous arsenate in an electrolyte promotes oxidation reactivity and passivation of the pyrite ***,the electron transfer rate increases with increasing aqueous arsenate concentration in the electrolyte.

关键词： Pyrite Aqueous arsenate Pyrite electrode Oxidation reactivity Electrochemistry

Catalytic Activity of Cr（Ⅵ） in the Degradation of Phenol by H2O2 Under Acidic Conditions

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Transactions of Tianjin University 2019年第6期25卷 567-575页

作者： Qingyou Zeng shaoyi jia Yufeng Gong Songhai Wu Xu Han School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China College of Environmental Science and Engineering Tongji UniversityShanghai 200092China Key Lab of Indoor Air Environment Quality Control School of Environmental Science and EngineeringTianjin UniversityTianjin 300072China

Cr(Ⅵ)and phenol are toxic contaminants that need to be treated,and different methods have been researched to simultaneously remove these two contaminants from industrial *** this study,Cr(Ⅵ)was used as a novel Fenton-like catalyst in phenol degradation by *** the pH range of 3.0-11.0,the degradation efficiency of phenol decreased with elevated *** pH=3.0,100 mg/L phenol was effectively degraded by 2 mmol/L Cr(Ⅵ)and 20 mmol/L *** pH=7.0 and the same conditions as those of pH=3.0,79%of 100 mg/L phenol was removed within 6h,which was an improvement in pH limitation compared with the Fe(Ⅱ)-mediated Fenton *** experiments indicated that·OH generated from the catalysis of H2O2 by Cr(Ⅴ)instead of Cr(Ⅵ)was the primary oxidant that degraded *** pyrophosphate was added in the Cr(Ⅵ)/H2O2 system,complexes with the Cr(Ⅴ)intermediate rapidly formed and inhibited H2O2 decomposition,implying that the decomposition of H2O2 to·OH was catalyzed by Cr(Ⅴ)instead of Cr(Ⅵ).The presence of anions such as chloride and sulfate had insignificant effect on the degradation of *** and UV analyses suggest that phenol could not be completely oxidized to CO2 and H2O,and the intermediates identified by high performance liquid chromatography further indicates that maleic acid and benzoquinone were intermediates which may be further degraded into short chain acids,primarily maleic,formic,acetic,and oxalic acids,and eventually into CO2 and *** that more than 50%Cr(Ⅵ)can also be removed during this process,the Cr(Ⅵ)/H2O2 system is more appropriate for the simultaneous removal of Cr(Ⅵ)and phenol contaminants from industrial wastewater.

关键词： Cr(Ⅵ) Cr(Ⅴ) Phenol Fenton Simultaneous degradation

Effect of Static Magnetic Field on α-Amylase Activity and Enzymatic Reaction

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Transactions of Tianjin University 2009年第4期15卷 272-275页

作者：贾绍义刘勇吴松海王志斌 School of Chemical Engineering and Technology Tianjin University

The effect of magnetic field on a-amylase was studied. Under the experimental conditions, a-amylase solution was treated by 0.15 T, 0.30 T and 0.45 T static magnetic fields for a known period of time, then the activity, kinetic parameters, and the secondary conformation were investigated. The results showed that there was a considerable effect of the magnetic exposure on the α-amylase. The activity was increased by 27%, 34.1%, 37.8% compared with the control. It was also found that both kinetic parameters Km and Vm could be decreased due to the increasing magnetic field, Km decreased from 2.20×10^2 to 0.87×10^2, whereas Vm decreased from 2.0×10^3 g/min to 1.1 ×10^3 g/min. At the same time, there were some irregular changes in a-amylase secondary conformation.

关键词： static magnetic field or-amylase activity secondary conformation Michaelis constant

Effect of Magnetic Field on the Extraction Process of Acetone-Water-Trichloroethane System

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Chinese Journal of Chemical Engineering 2007年第6期15卷 916-918页

作者：孙永利刘勇吴松海贾绍义 School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China

In order to investigate the effect of magnetic field on the liquid-liquid extraction, the extraction in the acetone-water-trichloroethane system was studied under magnetic field with different magnetic induction *** results showed that the effect of magnetic field was positive in the extraction process, and the partition coeffi-cient and the yield of acetone increased-with the increasing magnetic induction intensity by 5.16%-8.35% and 1.85%-5.70% respectively. The effect of magnetic field on the extraction was intensified when the temperature became, higher. The experimental data of the partition coefficient of acetone were correlated by the method of least square in terms of a power-law correlation.

关键词： magnetic field magnetic induction intensity liquid-liquid extraction acetone-water-trichloroethane

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元素周期律的发展及展望

曲阜师范大学学报（自然科学版） 1989年第2期15卷 33-37页

作者：贾绍义枣庄师专

本文阐述了自1869年发现元素周期律以后人们如何进一步发展和完善周期律的,同时对元素周期律的发展提出了有科学根据的设想。

关键词：元素周期律展望

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磁场处理对水-乙酸体系汽液平衡的影响

化学工程 2000年第5期28卷 56-59页

作者：柴诚敬贾绍义王军胡瑞杰张兵天津大学化工学院天津300072

在不同磁感应强度的磁场中 ,以不同的磁化处理方式和不同的磁化时间 ,研究了磁场处理对水 -乙酸体系汽液平衡的影响。研究结果表明 ,磁场对该体系的汽液平衡有一定的影响 ,磁化效果总体上呈正效应 ,但磁化效果与磁感应强度不成比例 ,有... 详细信息

在不同磁感应强度的磁场中 ,以不同的磁化处理方式和不同的磁化时间 ,研究了磁场处理对水 -乙酸体系汽液平衡的影响。研究结果表明 ,磁场对该体系的汽液平衡有一定的影响 ,磁化效果总体上呈正效应 ,但磁化效果与磁感应强度不成比例 ,有一个最佳值。在不同的磁化处理方式中 ,溶液达到充分磁化的时间不同 ,搅拌磁化效果优于静置磁化。磁化效果随溶液的组成而变 ,在乙酸摩尔组成为 0 .5 5～ 0 .

关键词：磁化磁场处理水-乙酸体系汽液平衡精馏

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磁场对稻谷干燥特性的影响

农业工程学报 2006年第7期22卷 166-169页

作者：吴松海孙永利贾绍义吴自俄天津大学化工学院天津300072 贵州省铜仁地区农业局铜仁554000

针对稻谷的传统干燥过程存在能量消耗大,发芽率低和爆腰率高等缺点,把磁场引入稻谷干燥过程中,能快速而经济地降低稻谷的水分并保持其良好品质。采用永磁场强化稻谷的干燥过程,比较干燥时间、发芽率和爆腰率的变化。结果表明:在相同功... 详细信息

针对稻谷的传统干燥过程存在能量消耗大,发芽率低和爆腰率高等缺点,把磁场引入稻谷干燥过程中,能快速而经济地降低稻谷的水分并保持其良好品质。采用永磁场强化稻谷的干燥过程,比较干燥时间、发芽率和爆腰率的变化。结果表明:在相同功率下稻谷在磁场中干燥时间比无磁场时缩短5%,平均失水速率加大,稻谷的发芽率有所升高、爆腰率下降;随着干燥功率的增加,磁场对稻谷的发芽率和爆腰率的影响加大。在试验基础上探讨了磁场对稻谷干燥过程的影响机理。

关键词：磁场稻谷干燥发芽率爆腰率

强背景噪声下滚动轴承轻微磨损故障特征提取方法

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煤炭工程 2023年第5期55卷 153-159页

作者：杨秀宇邵斌贾少毅赖岳华中煤华晋集团有限公司王家岭矿山西河津043300 北京天玛智控科技股份有限公司北京101399 煤炭科学研究总院北京100013

针对轴承轻微磨损故障信号容易被强背景噪声淹没,故障特征微弱难诊断的问题,提出了强背景噪声下滚动轴承轻微磨损故障特征提取方法。利用VMD对轴承振动信号进行分解,基于峭度最大准确选择最优本征模态函数,以最优本征模态函数的功率谱... 详细信息

针对轴承轻微磨损故障信号容易被强背景噪声淹没,故障特征微弱难诊断的问题,提出了强背景噪声下滚动轴承轻微磨损故障特征提取方法。利用VMD对轴承振动信号进行分解,基于峭度最大准确选择最优本征模态函数,以最优本征模态函数的功率谱熵最小为目标,设定提前终止准则,实现VMD参数自适应优化选择。轴承早期故障信号经参数优化后的VMD方法分解为多个本征模态函数,选择峭度最大的本征模态分量进行包络解调分析,结合快速傅里叶变换得到包络谱,实现故障特征频率的提取。通过对加强背景噪声的不同型号轴承的实测故障信号分析,结果均表明该方法能够在强背景噪声干扰下有效提取轻微磨损故障信号的故障特征,实现轴承轻微磨损故障的准确诊断,验证了该方法的有效性。

关键词：变分模态分解峭度功率谱熵轻微磨损故障