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Preparation, characterization and photocatalytic activities of boron- and cerium-codoped TiO_2

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Journal of Environmental Sciences 2007年第1期19卷 90-96页

作者： wei chao-hai TANG Xin-hu LIANG Jie-rong TAN Shu-ying institute of Environmental Science South China University of Technology Guangzhou 510640 China Department of Environrnental Engineering Jinan University Guangzhou 510632 China

Boron- and cerium-codoped TiO2 photocatalysts were synthesized using modified sol-gel reaction process and characterized by X- ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, particle size distribution （PSD）, diffuse reflectance spectra （DRS）, and Brunauer-Emmett-Teller （BET）. The photocatalytic activities were evaluated by monitoring the degradation of dye Acid Red B （ARB）. The results showed that the prepared photocatalysts were mixed oxides mainly consisting of titania, ceria, and boron oxide. The structure of TiO2 could be transformed from amorphous to anatase and then to rutile by increasing calcination temperature; the transformation being accompanied by the growth of particle size without any obvious change in phase structure of CeO2. The XPS of B1.6Ce1.0-TiO2 prepared at 500℃ showed that a few boron atoms were incorporated into titania and ceria lattice, whereas others existed as B2O3. Cerium ions existed in two states, Ce^3＋ and Ce^4＋, and the atomic ratio of Ce^3＋/Ce^4＋ was 1.86. When boron and cerium were doped, the UV-Vis adsorption band wavelength showed an obvious shift toward the visible range （〈526 nm）. As the atomic ratio of Ce/Ti increased to 1.0, the absorbance edge wavelength increased to 481 nm. The absorbance edge wavelength decreased for higher cerium doping levels （Ce/Ti=2.0）. The particles size ranged from 122 to 255 nm with a domain at 168 nm （39.4%）. The degradation of ARB dye indicated that the photocatalytic activities of boron- and cerium-codoped TiO2 were much higher than those of P25 （a standard TiO2 powder）. The activities increased as the boron doping increased, whereas decreased when the Ce/Ti atomic ratio was greater than 0.5. The optimum atomic ratio of B/Ti and Ce/Ti was 1.6 and 0.5, respectively.

关键词： titania ceria boron oxide photocatalytic activity Acid Red B

污废水中污染物去除的功能材料研究进展:元素物质-合成改性-工艺工程的尺度效应

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应用化学 2024年第2期41卷 190-216页

作者：庞子君覃智陈啊聪关翔鸿韦庚锐李泽敏黄华韦朝海华南理工大学环境与能源学院广州510006

污废水中的有机污染物、重金属离子和病毒性微生物等造成了严重的水环境污染,对人体健康和生态系统也造成严重威胁,有效控制污废水的风险成为保护环境和可持续发展的重要研究方向。环境功能材料作为一类具有污染物净化效果的辅助性手段... 详细信息

污废水中的有机污染物、重金属离子和病毒性微生物等造成了严重的水环境污染,对人体健康和生态系统也造成严重威胁,有效控制污废水的风险成为保护环境和可持续发展的重要研究方向。环境功能材料作为一类具有污染物净化效果的辅助性手段,在降低水污染风险中展现出巨大的科技潜力。本研究探讨元素物质的选择、合成改性策略和工艺工程的优化3个尺度层面的现状与发展;以碳元素、硅元素和金属元素为例,介绍新型功能材料的特征;从溶剂热法、溶胶-凝胶法、共沉淀法、化学气相沉积法、绿色合成法以及表面功能化改性讨论了合成技术策略;关于工艺工程应用方面,固定床-吸附床-流化床、电场-光场-磁场、物理-化学-生物、循环-再生-处置和协同放大效应等的产业生产/连续运行方面值得关注;在性能、经济性、环境影响和可持续性方面进行评价,强调了安全-稳定-长效-满负荷-优化的工艺工程技术应用目标。未来的环境功能材料发展应聚焦3D打印材料在污废水处理中的应用、智能工艺和智慧管理、群体感知和信息诊断以及场域效应和量子探针等技术方向的结合,在水质改善-材料功能挖掘-可持续循环发展方面提供新的技术领域。

关键词：环境功能材料污废水处理元素物质的选择合成改性策略工艺工程应用可持续评价

Hydrogen generation from polyvinyl alcohol-contaminated wastewater by a process of supercritical water gasification

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Journal of Environmental Sciences 2007年第12期19卷 1424-1429页

作者： YAN Bo wei chao-hai HU Cheng-sheng XIE Cheng WU Jun-zhang College of Environmental Science and Engineering South China University of Technology Guangdong 510640 China

Gasification of polyvinyl alcohol （PVA）-contaminated wastewater in supercritical water （SCW） was investigated in a continuous flow reactor at 723-873 K, 20-36 MPa and residence time of 20-450 s. The gas and liquid products were analyzed by GC/TCD, and TOC analyzer. The main gas products were H2, CH4, CO and CO2. Pressure change had no significant influence on gasification efficiency. Higher temperature and longer residence time enhanced gasification efficiency, and lower temperature favored the production of H2. The effects of KOH catalyst on gas product composition were studied, and gasification efficiency were analyzed. The TOC removal efficiency （RTOC）, carbon gasification ratio （RCG） and hydrogen gasification ratio （RHG） were up to 96.00%, 95.92% and 126.40% at 873 K and 60 s, respectively, which suggests PVA can be completely gasified in SCW. The results indicate supercritical water gasification for hydrogen generation is a promising process for the treatment ofPVA wastewater.

关键词： hydrogen generation supercritical water gasification polyvinyl alcohol wastewater

Characteristics of high-sulfate wastewater treatment by two-phase anaerobic digestion process with Jet-loop anaerobic fluidized bed

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Journal of Environmental Sciences 2007年第3期19卷 264-270页

作者： wei chao-hai, WANG Wen-xiang, DENG Zhi-yi, WU chao-fei School of Environmental Science and Engineering, South China University of Technology, Guangzhou 510640, China. School of Environmental Science and Engineering South China University of Technology Guangzhou 510640 China

A new anaerobic reactor, Jet-loop anaerobic fluidized bed （JLAFB）, was designed for treating high-sulfate wastewater. The treatment characteristics, including the effect of influent COD/SO42 ratio and alkalinity and sulfide inhibition in reactors, were discussed for a JLAFB and a general anaerobic fiuidized bed （AFB） reactor used as sulfate-reducing phase and methane-producing phase, respectively, in two-phase anaerobic digestion process. The formation of granules in the two reactors was also examined. The results indicated that COD and sulfate removal had different demand of influent COD/SO4^2- ratios. When total COD removal was up to 85%, the ratio was only required up to 1.2, whereas, total sulfate removal up to 95% required it exceeding 3.0. The alkalinity in the two reactors increased linearly with the growth of influent alkalinity. Moreover, the change of influent alkalinity had no significant effect on pH and volatile fatty acids （VFA） in the two reactors. Influent alkalinity kept at 400-500 mg/L could meet the requirement of the treating process. The JLAFB reactor had great advantage in avoiding sulfide and free-H2S accumulation and toxicity inhibition on microorganisms. When sulfate loading rate was up to 8. 1 kg/（m^3.d）, the sulfide and free-H2S concentrations in JLAFB reactor were 58.6 and 49.7 mg/L, respectively. Furthermore, the granules, with offwhite color, ellipse shape and diameters of 1.0-3.0 mm, could be developed in JLAFB reactor. In granules, different groups of bacteria were distributed in different layers, and some inorganic metal compounds such as Fe, Ca, Mg etc. were found.

关键词： Jet-loop anaerobic fluidized bed reactor sulfate wastewater two-phase anaerobic digestion process granule sludge

Supermassive black holes triggered by QCD axion bubbles

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Communications in Theoretical Physics 2024年第5期76卷 134-139页

作者： hai-Jun Li Ying-Quan Peng wei chao Yu-Feng Zhou Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Center for Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Beijing/HangzhouChina

Supermassive black holes(SMBHs)are ubiquitous in the center of galaxies,although the origin of their massive seeds is still *** this paper,we investigate the formation of SMBHs from the quantum chromodynamics(QCD)axion *** this case,primordial black holes(PBHs)are considered as the seeds of SMBHs,which are generated from the QCD axion bubbles due to an explicit Peccei–Quinn(PQ)symmetry breaking after *** QCD axion bubbles are formed when the QCD axion starts to oscillate during the QCD phase *** consider a general case in which the axion bubbles are formed with the bubble effective angle θ_(eff)∈(0,π],leading to the minimum PBH mass∼■(10^(4)−10^(7))M⊙for the axion decay constant f_(a)∼■(10^(16))*** PBHs at this mass region may account for the seeds of SMBHs.

关键词： supermassive black holes primordial black holes quantum chromodynamics axion

Analysis of sensitivity to hydrate blockage risk in natural gas gathering pipeline

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Petroleum Science 2024年第4期21卷 2723-2733页

作者： Ao-Yang Zhang Meng Cai Na wei hai-Tao Li chao Zhang Jun Pei Xin-wei Wang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Research Institute of Production Engineering Daqing Oilfield Co.Ltd.

During the operational process of natural gas gathering and transmission pipelines, the formation of hydrates is highly probable, leading to uncontrolled movement and aggregation of hydrates. The continuous migration and accumulation of hydrates further contribute to the obstruction of natural gas pipelines, resulting in production reduction, shutdowns, and pressure build-ups. Consequently, a cascade of risks is prone to occur. To address this issue, this study focuses on the operational process of natural gas gathering and transmission pipelines, where a comprehensive framework is established. This framework includes theoretical models for pipeline temperature distribution, pipeline pressure distribution, multiphase flow within the pipeline, hydrate blockage, and numerical solution methods. By analyzing the influence of inlet temperature, inlet pressure, and terminal pressure on hydrate formation within the pipeline, the sensitivity patterns of hydrate blockage risks are derived. The research indicates that reducing inlet pressure and terminal pressure could lead to a decreased maximum hydrate formation rate, potentially mitigating pipeline blockage during natural gas transportation. Furthermore, an increase in inlet temperature and terminal pressure, and a decrease in inlet pressure, results in a displacement of the most probable location for hydrate blockage towards the terminal station. However,it is crucial to note that operating under low-pressure conditions significantly elevates energy consumption within the gathering system, contradicting the operational goal of energy efficiency and reduction of energy consumption. Consequently, for high-pressure gathering pipelines, measures such as raising the inlet temperature or employing inhibitors, electrical heat tracing, and thermal insulation should be adopted to prevent hydrate formation during natural gas transportation. Moreover, considering abnormal conditions such as gas well production and pipeline network s

关键词： Natural gas hydrates Gathering pipeline Temperature variation Hydrate formation rate Sensitivity analysis

Polyoxometalates-derived nanostructures for electrocatalysis application

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Rare Metals 2024年第5期43卷 1845-1866页

作者： chao-Yue Sun Wen Li Kai Wang wei-Jia Zhou hai-Qing Wang Institute for Advanced Interdisciplinary Research(iAIR) College of Chemistry and Chemical EngineeringUniversity of JinanJinan250022China Shandong Electrical Engineering and Equipment Group Intelligent Electric Co. Ltd.Jinan 250022China

The conversion of intermittent renewable electrical energy to chemical energy is of great importance which can not only mitigate current energy and environmental crisis but also contribute to the ongoing carbon neutrality national *** is serving as a low-carbon conversion technology that enables green and efficient energy conversion mainly through hydrogen evolution reaction(HER),carbon dioxide reduction reaction(CO_(2)RR),and nitrogen reduction reaction(NRR).The core of electrocatalysis is the design and construction of low-cost high-activity and high-stability electrocatalyst to drive reaction thermodynamics and *** employment of polyoxometalates(POMs)as platforms or precursors to construct different types of electrocatalysts has been widely ***,we systematically summarized the recent advances in POM-derived nanostructures for electrocatalysis *** strategies for precursor design and electrocatalyst synthesis were briefly *** morphology control,phase control,composite modulation,and heterostructure engineering in POM-derived nanostructures were presented in *** structure–activity relationship of POM-derived nanostructures is fully discussed for HER CO_(2)RR,and NRR ***,the current challenges and future outlooks of POM-derived nanostructures are summarized to provide insights toward high-efficiency electrocatalysts for energy conversion technologies.

关键词： Microforming Cylindrical compression Size effects Grain orientation Inhomogeneous deformation

Beneficial metabolic effects of nateglinide versus acarbose in patients with newly-diagnosed type 2 diabetes

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Acta Pharmacologica Sinica 2007年第4期28卷 534-539页

作者： Hong-wei GAO chao XIE hai-ning WANG Yu-jing LIN Tian-pei HONG Department of Endocrinology,Peking University Third Hospital,Beijing 100083,China Department of Endocrinology Peking University Third Hospital Beijing China

Aim:To investigate the acute and chronic effects of nateglinide versus acarboseon plasma asymmetric dimethylarginine (ADMA) levels and lipid profiles inpatients with newly-diagnosed type 2 ***:A crossover trial ofnateglinide and acarbose was conducted on 16 drug-nave patients with newly-diagnosed type 2 diabetes during a total period of 9 *** glucose,seruminsulin,free fatty acids (FFA),lipids and lipoproteins,and plasma ADMA ***:The efficiencies of a single dose of nateglinide (120 mg) andacarbose (50 mg) for lowering postprandial hyperglycemia were ***-pared to acarbose,nateglinide significantly increased postprandial insulin releaseafter a standard meal test in patients with type 2 *** acutelydecreased postprandial 120 min FFA concentrations and 240 min ADMA levelsmore significantly than *** fasting high-density lipoprotein choles-terol level increased and the low-density lipoprotein cholesterol level decreasedsignificantly,but the fasting levels of triglycerides,total cholesterol,and ADMAwere unchanged after 4 weeks of treatment with *** did notaffect fasting lipid profiles or the ADMA levels after 4 weeks of ***:These results suggest that the reduction of postprandial FFA andADMA concentrations induced by nateglinide may be associated with the partialrestoration of early-phase insulin secretion and may impart a cardiovascularadvantage in comparison with acarbose.

关键词： nateglinide acarbose free fatty acids asymmetric dimethylarginine

Role of bonding filling on HER/OER/ORR multifunctional catalytic activity in transition-metals-doped PdPX(X=S,Se,Te)

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Rare Metals 2024年第10期43卷 5126-5140页

作者： hai-Hua Huang wei Li Cheng-chao Hu Xue-Qin Sun Lin-Guo Lu Xiao-Feng Fan School of Materials Science and Engineering Laboratory of Sensitive Materials and DevicesShandong Department of EducationLiaocheng University School of Environmental and Material Engineering Yantai University Department of Physics University of Puerto Rico Key Laboratory of Automobile Materials (Jilin University) Ministry of EducationCollege of Materials Science and EngineeringJilin University

The development of stable and highly efficien multifunctional electrocatalysts for the hydrogen evolution reaction （HER）,oxygen reduction reaction （ORR） and oxygen evolution reaction （OER） are essential for the efficient conversion and storage of renewable *** significant advantages of single-atom catalysts,such as strong metal slab interactions,unsaturated coordination and efficient atomic utilization,have opened new avenues for designing multifunctional ***,based on density functional theory,a single atom doped PdPX system was designed as a multifunctional electrocatalyst,which demonstrated the synergistic effect between defects and transition metal atoms and led to enhanced catalytic *** results showed that PdPS/PdPSe with P/X vacancy,PdPTe with P/Pd vacancy and Co/Rh/Ir@PdPX exhibited promising HER ***@PdPS（Se）,with an overpotential of 0.56（0.44） V,was predicted to be a promising OER ***,Rh（Ir）@PdPS（Se）catalysts exhibited efficient catalytic properties for ORR Besides,Co@PdPS（Se）,Rh（Ir）@PdPSV（S）,Co@PdP-SeV（Se）and Ir@PdPSV（S）-1exihibited multifunctional catalytic performance with moderate ***,the origin of catalytic activity was revealed by using the crystal orbital Hamilton populations *** a strong adsorption system,proper filling of the anti-bonding state can increase the energy of the system,weaken the adsorption strength,and facilitate the desorption of intermediates Conversely,augmenting bonding states can enhance its adsorption *** findings provide theoretica guidance for the design and fabrication of novel multifunctional electrocatalysts in terms of filling of bondingstate.

关键词： Density functional theory Electrocatalyst Two-dimensional PdPX Water splitting