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Enhanced photocatalytic performance by regulating the Ce^(3+)/Ce^(4+)ratio in cerium dioxide

Frontiers of Chemical Science and Engineering 2024年第3期18卷 75-87页

作者： Zhi Li Dongsheng Jia Wei zhang Ying Li Mitang Wang Dongliang Zhang School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai200093China

Cerium dioxide(CeO_(2))photocatalysts are used in treating environmental pollution and addressing the energy crisis due to their excellent oxygen storage capacities and abundant oxygen vacancies.In this paper,CeO_(2)precursors were synthesized with different water-alcohol ratios via a solvothermal method,and CeO_(2)photocatalysts with different Ce^(3+)/Ce^(4+)ratios were obtained by changing the precursor calcination atmospheres(air,Ar)as well as the calcination time.The effects of CeO_(2)with different Ce^(3+)/Ce^(4+)ratios in photocatalytic degradations of methylene blue under visible light were investigated.X-ray photoelectron spectroscopy results showed that the surfaces of the samples calcined under Ar had higher Ce^(3+)/Ce^(4+)ratios and oxygen vacancy concentrations,which reduced the band gaps of the catalysts and improved their utilization of visible light.In addition,the many Ce^(3+)/Ce^(4+)redox centers and oxygen vacancies on the sample surfaces improved the separation and transfer efficiencies of the photogenerated carriers.The sample C2-Ar calcined under Ar showed a high adsorption capacity and excellent photocatalytic activity by removing 96%of the methylene blue within 120 min,which was more than twice the degradation rate of the sample(C2-air)prepared via calcination under air.Trapping experiments showed that photogenerated holes played a key role in the photocatalytic process.In addition,a synergistic photocatalytic mechanism for the Ce^(3+)/Ce^(4+)redox centers and oxygen vacancies was elucidated in detail,and the sensitization of cerium dioxide by dyes aided the degradation of methylene blue.

关键词： CeO_(2) oxygen vacancies Ce^(3+)/Ce^(4+)ratios photocatalytic dye-sensitization

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A Darcy-Law Based Model for Heat and Moisture Transfer in a Hill Cave

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Fluid Dynamics & Materials Processing 2023年第9期19卷 2345-2359页

作者： Fei Liu Dongliang Zhang Qifu Zhu Qingyong Su College of Energy and Building Environment Guilin University of Aerospace TechnologyGuilin541004China College of Mechanical and Electrical Engineering Guilin University of Aerospace TechnologyGuilin541004China

A hill can be regarded as an environmental carrier of heat.Water,rocks and the internal moisture naturally pre-sent in such environment constitute a natural heat accumulator.In the present study,the heat and moisture trans-fer characteristics in a representative hill cave have been simulated via a method relying on the Darcy’s law.The simulations have been conducted for both steady and unsteady conditions to discern the inﬂuence of permeability and geometric parameters on the thermal and moisture transfer processes.The reliability of the simulation has been veriﬁed through comparison of the numerical results with the annual observation data.As revealed by the numericalﬁndings,the internal temperature of the hill accumulator is proportional to the permeability,outside surface temperature,overground height,underground constant temperature layer depth,and underground tem-perature of the hill,and it is inversely proportional to the horizontal size of the hill.Moreover,in the considered case,the order of magnitude of the permeability of the hill is contained in the range 10-15–10-13,and displays a certain sensitivity to the rainwater seepage.

关键词： Cave hill thermal and moisture transfer Darcy’s law temperatureﬁeld permeability

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Easily fabricated and recyclable Pd&Cu@Al catalyst for gram-scale phosphine-free Heck reactions with high TON

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Science Bulletin 2017年第19期62卷 1325-1330页

作者： Dongliang Zhang Zheng Wei Lei Yu Institute of Pesticide School of Horticulture and Plant ProtectionYangzhou University School of Chemistry and Chemical Engineering Yangzhou University

A unique Pd&Cu@Al catalyst was easily fabricated just by immersing commercial aluminum foil in a mixed xylene solution of PdCl_2 and CuCl_2. The catalyst fabrication process led to aluminum oxide coatings in situ, which supported the metal nanoparticles and enhanced their catalytic activities for the phosphine-free Heck reaction of aryl halides and styrenes with high turnover number(TON) up to 3.9×10~5. The reaction can be scaled up to at least 100 mmol and has been applied in modification of drug Lapatinib's intermediate with low metal residue. This novel catalyst is of good application potential in industrial production because it was extremely easy to be recycled, in regardless of the generation of the insoluble impurities or tars during the reaction processes.

关键词： Heck反应新型催化剂铝箔金属纳米粒子回收制造膦铜

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Tailoring effect of Y_(2)O_(3)on water resistance of Na_(2)O-ZnO-Al_(2)O_(3)-B_(2)O_(3)glasses

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Journal of Rare Earths 2022年第8期40卷 1316-1322页

作者： Mitang Wang Ao Li Xiaowei zhang Dongliang Zhang Siqingaowa Jin Dehua Xiong Wei Deng School of Materials Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Silicate Materials for Architecture Wuhan University of TechnologyWuhan 430070China Materials and Engineering Research Institute Sheffield Hallam UniversitySheffieldS11WBUK

To explore the improving effect of Y_(2)O_(3)on the water resistance of xY_(2)O_(3)-(100-x)(0.05 Al_(2)O_(3)-0.15 ZnO-0.15 Na_(2)O-0.65 B_(2)O_(3))(x=0,0.7 mol%,1.4 mol%,2.1 mol%,2.8 mol%)glasses,glass structure and ion migration characteristics were respectively characterized by an infrared spectrometer and an electrochemical workstation.X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive Xray spectroscopy(EDS)and inductively coupled plasm-atomic emission spectrometry(ICP-AES)were used to comprehensively analyze the alteration products.The experimental results show that with the increase of Y_(2)O_(3)content,the mass loss per unit area of the glass is significantly reduced,and pH in leaching solution has the same change trend with mass loss of the glass,which indicates the improving effect of Y_(2)O_(3)addition on the studied glass.The content of[BO_(4)]structural unit and dc conductivity of glass increase firstly and then decrease with the increase of Y_(2)O_(3)content,and reach a maximum at x=0.7 mol%.Although addition of Y_(2)O_(3)plays the role in the changes of glass structure and ion migration characteristics,the more important influence of Y_(2)O_(3)is on the glass surface alteration layer.Y and Zn elements are enriched on the glass surface and finally transformed into an alteration layer,moreover,the adhesion between the alteration layers and the glass matrix is enhanced with the increase of Y_(2)O_(3)content,which effectively blocks the further interdiffusion between the water molecules and the glass matrix.

关键词： Borate glass Chemical durability Y_(2)O_(3) Structure Rare earths

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Merging cobalt catalysis and electrochemistry in organic synthesis

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Chinese Chemical Letters 2021年第3期32卷 963-972页

作者： Junsong Zhong Yi Yu Dongliang Zhang Keyin Ye Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou UniversityFuzhou 350108China

There is an increasing demand of using the low-cost and sustainable cobalt to replace its noble congeners(rhodium and iridium)as reflected by the recent upsurge of cobalt catalysis in the diverse organic transformations.Since all the redox reactivity of cobalt catalysis highly relies on the capability of the interconversion between their oxidation states(most frequently+1,+2 and+3),electrochemistry perfectly meets such a require ment owing to its outstanding perfo rmance in the redox manipulation.In this review,we highlight the recent advances in the merger of cobalt catalysis and electrochemistry in organic synthesis.

关键词： Cobalt Catalysis Electrochemistry Organic synthesis Sustainable chemistry

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Vegetation dynamics and its response to climate change during the past 2000 years in the Altai Mountains,northwestern China

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Frontiers of Earth Science 2022年第2期16卷 513-522页

作者： Dongliang Zhang Yunpeng YANG Min RAN Bo LAN Hongyan ZHAO Qi LIU State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Research Center for Ecology and Environment of Central Asia Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China College of Environment and Planning Henan UniversityKaifeng 475004China Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions(Ministry of Education) Henan UniversityKaifeng 475004China School of Environmental and Chemical Engineering Chongqing Three Gorges UniversityChongqing 404000China School of Earth Science Northeast Normal UniversityChangchun 130024China College of Resource and Environmental Sciences Xinjiang UniversityUrumqi 830046China

Over the past 2000 years,a high-resolution pollen record from the Yushenkule Peat(46°45′-46°57′N,90°46′-90°61′E,2374 m a.s.l.)in the south-eastern Altai Mountains of northwestern China has been used to explore the changes in vegetation and climate.The regional vegetation has been dominated by alpine meadows revealed from pollen diagrams over the past 2000 years.The pollen-based climate was warm and wet during the Roman Warm Period(0-520 AD),cold and wet during the Dark Age Cold Period(520-900 AD),warm and wet during the Medieval Warm Period(900-1300 AD),and cold and dry during the Little Ice Age(1300-1850 AD).Combined with other pollen data from the Altai Mountains,we found that the percentage of arboreal pollen showed a reduced trend along the NW-SE gradient with decreasing moisture and increasing climatic continentality of the Altai Mountains over the past 2000 years;this is consistent with modern distributions of taiga forests.We also found that the taiga(Pinus forest)have spread slightly,while the steppe(Artemisia,Poaceae and Chenopodiaceae)have recovered significantly in the Altai Mountains over the past 2000 years.In addition,the relatively warm-wet climate may promote high grassland productivity and southward expansion of steppe,which favors the formation of Mongol political and military power.

关键词： pollen analysis vegetation dynamics past 2000 years Altai mountains northwestern China

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Mechanism of phthalic acid collector in flotation separation of fluorite and rare earth

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Journal of Rare Earths 2022年第1期40卷 118-126页

作者： Sheng Chang Mei Li Kai Gao Dongliang Zhang Haijun Duan Linlin Ma Zheng Ruan College of Mining Inner Mongolia University of Science&TechnologyBaotou 014010China Key Laboratory of Green Extraction&Efficient Utilization of Light Rare-Earth Resources Ministry of Education Baotou 014010China Inner Mongolia Key Laboratory of Rare Earth Hydrometallurgy and Light Rare Earth Application Baotou 014010China Inner Mongolia Mining Exploitation Co. Ltd.Hohhot 010020China

The mechanism of phthalic acid,a dicarboxylic acid collector,in flotation separation of fluorite and rare earth(RE)was studied in this paper.The experimental data of flotation show that phthalic acid,as the collector,can realize highly efficient separation of fluorite and rare earth under weakly acidic conditions.The adsorption mechanism of phthalic acid on the surface of fluorite and bastnaesite was analyzed in this paper by means of the zeta potential measurement,the Fourier transform infrared(FT-IR),the X-ray photoelectron spectroscopy(XPS)and the stability constant measurement of active metal ion and phthalic acid coo rdination complex.According to the zeta potential testing results,the surfaces of fluorite adsorb the collector phthalate ion with negative charge under weakly acidic conditions which,in turn,increases its electronegativity and results in the motion of its potential.After the reaction between phthalic acid and fluorite ores under weakly acidic conditions,the peak of the fluorite ores is found to have significant changes in the FT-IR results,indicating strong chemical adsorption on the surfaces of phthalic acid and fluorite ores.According to the XPS analysis,the peak of benzene ring of phthalic acid is as high as 2%on the surface of fluorite,while no obvious characteristic peak of benzene ring is found on the surface of bastnaesite.According to the pH potentiometric titration results,the stability constant Ktotal of calcium phthalate complex within the acid range is higher than the stability constant K’total of cerium phthalate complex,indicating that the complex generated between phthalic acid and Ca^(2+)is more stable than the complex generated between phthalic acid and Ce^(3+).The possible reason is that Ca^(2+),with the highest reticular density,plays a prevailing role in the octahedron structure of fluorite amidst the acidic media.As the active point of flotation,Ca^(2+)works with the carboxyl groups of the collector phthalic acid(-C=O-)to form polycyclic calcium phthalate complex.

关键词： Fluorite Bastnaesite Carboxylic acid collector Flotation Equilibrium constants of complexes Rare earths

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Changes in the root system of the herbaceous peony and soil properties under different years of continuous planting and replanting

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Horticultural Plant Journal 2023年第4期9卷 801-810页

作者： Anqi Xie Limin Sun Dongliang Zhang Yang Li Zemiao Liu Xue Li Xia Sun College of Horticulture State Key Laboratory of Crop BiologyShandong Agricultural UniversityTai'anShandong 271018China College of Forestry Shandong Agricultural UniversityTai'anShandong 271018China

The herbaceous peony(Paeonia lactiflora Pall.)has high ornamental value.Replanting problems occur when seedlings are replanted into previous holes.We studied the root system and soil environment of the'Dongjingnvlang'variety under a continuous planting regime of one,four,and seven years,and a replanting regime of one and four years.Under the condition of continuous planting,with the increase of number of years,pH,ammonium nitrogen,and nitrate nitrogen decreased in the rhizosphere and non-rhizosphere soils,whereas organic matter,available phosphorus and potassium,enzyme activities,and the number of bacteria,fungi,and actinomycetes increased.Under the condition of replanting,with the increase of number of years,fungi and actinomycetes in both soils increased,while pH,organic matter,nutrients,enzyme activities,and bacterial number decreased.pH,organic matter,nutrient content,enzyme activity and the number of bacterial were lower in soil replanted for four years,whereas the abundance of fungi and actinomycetes was higher,altering the soil from“bacterial high-fertility”to“fungal low-fertility”with increasing years of replanting.The activity of antioxidant enzymes and MDA content in roots of peony in replanting were higher than those in continuous planting,while the content of osmotic regulatory substances in replanting was lower than that in continuous planting.The results showed that there were no obvious adverse factors in soil during seven years of continuous planting,and herbaceous peony could maintain normal growth and development.However,soils after four years of replanting were not suitable for herbaceous peony growth.Benzoic acid increased with years of replanting,which potentially caused replanting problems.This study provides a theoretical basis for understanding the mechanism of replanting problems in the herbaceous peony.

关键词： Herbaceous peony Replanting problems Continuous planting Soil environment Phenolic acids Paeoniflorin

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Effect of Vortex Stirring on the Dilution of Copper Slag

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Journal of Wuhan University of Technology(Materials Science) 2022年第4期37卷 699-706页

作者：张保敬张廷安 DOU Zhihe zhang dongliang School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221l6China School of Metallurgy Northeastern UniversityShenyang 110819China

In order to solve the problem that the vulcanizing agent utilization rate is low and the dilution effect of copper slag is poor,the vortex stirring dilution method was used to improve the conditions of the dilution kinetics and copper recovery.The water model was used to simulate the effect of copper slag dilution.Under the premise of keeping the Reynolds number consistent,silicone oil and glass beads were used instead of copper slag and vulcanizing agent.Based on the relationship between voltage and concentration,the PC6D dual-channel particle concentration measuring instrument was used to study the stirring speed and the insertion depth of the stirring paddle in model experiments,and the suitable conditions were speed 250 rpm and insertion depth 70 mm.The fire dilution of copper slag was done under the conditions.After stirring and sedimentation,the Fe_(3)O_(4) in slag decreased from 22.58% to 4.65%,and the copper content of the slag decreased from 2.94% to 0.34%.The copper recovery was 88.44%.

关键词： copper slag dilution vortex stirring water model the PC6D dual-channel particle concentration measuring instrument

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Muscular tissue desaturation and pneumonia in patients receiving lung cancer surgery:a cohort study

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Chinese Medical Journal 2023年第1期136卷 65-72页

作者： Wei Zhao Caijuan zhang dongliang Mu Fan Cui Huiqun Jia Department of Anesthesiology The Fourth Hospital of Hebei Medical UniversityShijiazhuangHebei 050000China Department of Anesthesiology Peking University First HospitalBeijing 100034China Department of Anesthesiology Tangshan Gongren HospitalTangshanHebei 063000China

Background:Post-operative pneumonia(POP)is a common complication of lung cancer surgery,and muscular tissue oxygenation is a root cause of post-operative complications.However,the association between muscular tissue desaturation and POP in patients receiving lung cancer surgery has not been specifically studied.This study aimed to investigate the potential use of intra-operative muscular tissue desaturation as a predictor of POP in patients undergoing lung cancer surgery.Methods:This cohort study enrolled patients(≥55 years)who had undergone lobectomy with one-lung ventilation.Muscular tissue oxygen saturation(SmtO_(2))was monitored in the forearm(over the brachioradialis muscle)and upper thigh(over the quadriceps)using a tissue oximeter.The minimum SmtO_(2)was the lowest intra-operative measurement at any time point.Muscular tissue desaturation was defined as a minimum baseline SmtO_(2)of15 s.The area under or above the threshold was the product of the magnitude and time of desaturation.The primary outcome was the association between intra-operative muscular tissue desaturation and POP within seven post-operative days using multivariable logistic regression.The secondary outcome was the correlation between SmtO_(2)in the forearm and that in the thigh.Results:We enrolled 174 patients.The overall incidence of muscular desaturation(defined as SmtO_(2)<80%in the forearm at baseline)was approximately 47.1%(82/174).The patients with muscular desaturation had a higher incidence of pneumonia than those without desaturation(28.0%[23/82]vs.12.0%[11/92];P=0.008).The multivariable analysis revealed that muscular desaturation was associated with an increased risk of pneumonia(odds ratio:2.995,95%confidence interval:1.080-8.310,P=0.035)after adjusting for age,American Society of Anesthesiologists status,Assess Respiratory Risk in Surgical Patients in Catalonia score,smoking,use of peripheral nerve block,propofol,and study center.Conclusion:Muscular tissue desaturation,defined as a baseline SmtO_(2)<80%in the forearm,m

关键词： Association Lung neoplasms Muscular tissue oxygenation One-lung ventilation Post-operative complications Pneumonia Propofol Oxygen saturation

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