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Efficient visible light photo-Fenton-like degradation of organic pollutants using in situ surface-modified BiFeO_3 as a catalyst

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Journal of Environmental Sciences 2013年第6期25卷 1213-1225页

作者： Junjian An Lihua Zhu yingying zhang Heqing Tang College of Chemistry and Chemical Engineering Huazhong University of Science and Technology Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education College of Chemistry and Materials ScienceSouth-Central University for Nationalities

The visible light photo-Fenton-like catalytic performance of BiFeO3 nanoparticles was investigated using Methyl Violet （MV）, Rhodamine B （RhB） and phenol as probes. Under optimum conditions, the pseudo first-order rate constant （k） was determined to be 2.21 × 10^-2, 5.56 × 10^-2 and 2.01 × 10^-2 min〈 for the degradation of MV （30 μmol/L）, RhB （10 μmol/L） and phenol （3 mmol/L）, respectively, in the BiFeO3-H202-visible light （Vis） system. The introduction of visible light irradiation increased the k values of MV, RhB and phenol degradation 3.47, 1.95 and 2.07 times in comparison with those in dark. Generally, the k values in the BiFeO3- H202-Vis system were accelerated by increasing BiFeO3 load and H202 concentration, but decreased with increasing initial pollutant concentration. To further enhance the degradation of pollutants at high concentrations, BiFeO3 was modified with the addition of surface modifiers. The addition of ethylenediamineteraacetic acid （EDTA, 0.4 mmol/L） increased the k value of MV degradation （60 μmol/L） from 1.01 × 10.2 min^-1 in the BiFeO3-H202-Vis system to 1.30 min^-1 in the EDTA-BiFeO3-H2O2-Vis system by a factor of 128. This suggests that in situ surface modification can enable BiFeO3 nano-particles to be a promising visible light photo-Fenton-like catalyst for the degradation of organic pollutants.

关键词： nanoscale BiFeO3 visible light photo-Fenton-like catalysis degradation surface modification

Characteristics and source apportionment of PM_(2.5) under the dual influence of the Spring Festival and the COVID-19 pandemic in Yuncheng city

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Journal of Environmental Sciences 2023年第3期125卷 553-567页

作者： Chen zhang yingying zhang Xingang Liu Yafei Liu Chenlu Li State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China Beijing Capital Air Environmental Science&Technology Co. Ltd.Beijing 100176China

Based on the online and membrane sampling data of Yuncheng from January 1st to February 12th,2020,the formation mechanism of haze under the dual influence of Spring Festival and COVID-19 (Corona Virus Disease) was *** capacity,chemical composition,secondary transformation,source apportionment,backward trajectory,pollution space and enterprise distribution were *** wind speed,high humidity and small atmospheric capacity inhibited the diffusion of air *** severe pollution processes occurred during the period,and the pollution degree was the highest around the Spring *** light,medium and heavy pollution periods,the proportion of SNA (SO_(4)^(2-),NO_(3)-and NH_(4)^(+)) was 59.6%,56.0%and 54.9%,respectively,which was the largest components of PM_(2.5);the[NO_(3)-]/[SO_(4)^(2-)]ratio was 2.1,1.5 and 1.7,respectively,indicating that coal source had a great influence;the changes of NOR (nitrogen oxidation ratio,0.44,0.45,0.61)and SOR (sulphur oxidation ratio,0.40,0.49,0.65) indicated the accumulation of secondary aerosols with increasing *** coal combustion,motor vehicle,secondary inorganic sources and industrial sources contributed 36.8%,26.59%,11.84%and 8.02%to PM_(2.5)masses,*** trajectory showed that the influence from the east was greater during the Spring Festival,and the pollutants from the eastern air mass were higher,which would aggravate the *** and Spring Festival had a great impact on heavy pollution *** some work could not operate due to the impact of the COVID-19 epidemic,the emission of pollutants did not reduce much.

关键词： PM_(2.5) COVID-19(Corona Virus Disease) Yuncheng Secondary conversion Source apportionment

Comparison of molybdenizing and NiCrAlY coating on Ti and Ti-6Al-4V

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Rare Metals 2009年第1期28卷 49-56页

作者： PENG Xiaomin XIA Changqing LIU yingying zhang Zhigao School of Materials Science and Engineering Central South University Changsha 410083 China

Two surface treatments, molybdenizing and depositing NiCrAIY coating, were applied to improve the microhardness and the oxidation resistance of titanium and Ti-6Al-4V. Coupons were analyzed using optical microscopy （OM）, scanning electron microscopy （SEM） with X-ray energy dispersive spectrometer （EDS）, and X-ray diffraction （XRD）. Vickers hardness and isothermal oxidation tests were carried out to evaluate the effects of these two surface treatments on the microhardness and oxidation resistance of the substrates. The post vacuum heat treatment of the NiCrAlY coating and the molybdenizing parameters were also discussed. It is found that molybdenizing can obviously increase the surface hardness of titanium due to the formation of β, α＂, and α″ phases in the diffusion layer. As γ＇ phase is formed after vacuum heat treatment, the NiCrAlY coating is effective in improving the surface hardness of Ti-6Al-4V. The NiCrAlY coating can obviously decrease the oxidation rate of Ti-6Al-4V at 700-900℃, which can be attributed to the formation of Al2O3 and Cr2O3 mixed scale during the oxidation.

关键词： NiCrA1Y coating molybdenizing microhardness oxidation resistance

Rethinking sepsis after a two-year battle with COVID-19

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Cellular & Molecular Immunology 2022年第11期19卷 1317-1318页

作者： yingying zhang Jiahuai Han State Key Laboratory of Cellular Stress Biology Innovation Center for Cell BiologySchool of Life SciencesXiamen UniversityXiamenFujianChina Laboratory Animal Center Xiamen UniversityXiamenFujianChina Research Unit of Cellular Stress of CAMS Cancer Research Center of Xiamen UniversityXiang’an Hospital of Xiamen UniversitySchool of MedicineXiamen UniversityXiamenFujianChina

Sepsis is an overwhelming host reaction to infection that results in high morbidity and *** term sepsis or septicemia originated in 1914,and the definition of sepsis has evolved over time due to the complications of the *** inflammatory response syndrome(SIRS)and infection are characteristics of sepsis;however,in the absence of infection,SIRS does not lead to sepsis,and not all cases of sepsis manifest symptoms of systemic inflammation,especially in elderly individuals.

关键词： sepsis SIRS infection

Hollow cubic MnS-CoS_(2)-NC@NC designed by two kinds of nitrogen-doped carbon strategy for sodium ion batteries with ultraordinary rate and cycling performance

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Nano Research 2022年第4期15卷 3273-3282页

作者： Ruipeng Wei Yutao Dong yingying zhang Xiyang Kang Xia Sheng Jianmin zhang College of Science Henan Agricultural UniversityZhengzhou 450002China College of Chemistry Zhengzhou UniversityZhengzhou 450001China

In order to obtain an advanced anode material that exhibits excellent electrochemical performance in sodium ion batteries,a hollow nanocube MnS-CoS_(2)-NC@NC(NC=nitrogen-doped carbon)with two kinds of nitrogen-doped carbon was synthesized by simple one-step *** of the two kinds of nitrogen-doped carbon comes from the organic ligands in the precursor being mixed in the sulfide after calcination,and the other comes from the calcination of the coated polydopamine(PDA)to form a carbon shell wrapped outside the *** characteristic nanostructure with two kinds of nitrogen-doped carbon can not only improve the overall conductivity of the electrode material,which is obviously beneficial to the rapid transmission of sodium ions and thus outstanding rate performance,but also can alleviate volume expansion to maintain battery cycle *** the half-cell,the MnS-CoS_(2)-NC@NC electrode not only provides an ultra-high specific capacity of 608.5 mA·h·g^(-1)at 0.2 A·g^(-1)for 100 cycles,but also shows an outstanding rate performance of 560.5 mA·h·g^(-1)at 5.0 A·g^(-1)for 1,100 *** in a full-cell composed with Na3V2(PO4)3 as the positive material,it can still maintain a capacity of 436.7 mA·h·g^(-1)after 900 cycles at 1.0 A·g^(-1).In order to explore its sodium storage mechanism,in-situ and ex-situ X-ray diffraction(XRD)tests were carried out to prove that CoS_(2)and MnS were reduced to produce metallic Co and metallic Mn during the discharging process,respectively,and reversibly returned during the charging process.

关键词： MnS CoS_(2) hollow nanocube nitrogen-doped carbon sodium ion battery

N-Heterocyclic Carbene Copper(Ⅰ)Complex Catalyzed Coupling of(Hetero)aryl Chlorides and Nitrogen Heterocycles:Highly Efficient Catalytic System

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Chinese Journal of Chemistry 2020年第11期38卷 1252-1256页

作者： Mengyao zhang yingying zhang Huixin zhang Yongfei Zeng Guiyan Liu Tianjin Key Laboratory of Structure and Performance for Functional Molecules Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry(Tianjin Normal University)Ministry of EducationCollege of ChemistryTianjin Normal UniversityTianjin 300387China

of main observation and conclusion A highly efficient catalytic system for the N-arylation reactions of(hetero)aryl chlorides and nitrogen heterocycles with a copper(l)complex containing a 1,10-phenanthroline analogue N-heterocyclic carbene(NHC)has been *** complex was characterized by^lH NMR and^13C NMR spectroscopy and elemental analysis,and its structure was determined by single-crystal X-ray *** NHC-copper(l)complex was employed as pre-catalyst for Ullmann type N-arylation reactions of(hetero)aryl chlorides with various azoles.A variety of hindered and functionalized azoles and(hetero)aryl chlorides were transformed in good to excellent yields.

关键词： diffraction. copper Catalytic

Thermal Stability of Fe_2O_3 Nanowires

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Journal of Materials Science & Technology 2008年第4期24卷 594-596页

作者： Xiongdian zhang Qin HAN Zhao DONG yingying XU Han zhang State Key Laboratory for Mesoscopic Physics Department of Physics Peking University. Beijing 100871 China

The thermal stability of α-Fe203 and γ-Fe2O3 nanowires was studied by post annealing the samples at different temperatures. Before and after annealing, the samples were characterized by X-ray diffraction and scanning electron microscopy. The α-Fe2O3 nanowires are stable at the temperatures up to 600℃, and the crystalline structure becomes more perfect after annealing. This behavior supplies a way to improve the quality of the α-Fe2O3 nanowires. The γ-Fe2O3 nanowires become unstable when annealed at 350℃. Raman spectra of both nanowires have been measured, which also indicate that the γ-Fe203 nanowires are transformed into α-Fe2O3 under the strong laser beam.

关键词： Fe2O3 nanowire Thermal stability Structural transformation

Rapid report of source parameters of 2023 M6.2 Jishishan,Gansu earthquake sequence

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Earth and Planetary Physics 2024年第2期8卷 436-443页

作者： ZhiGao Yang Jie Liu yingying zhang Wen Yang XueMei zhang China Earthquake Networks Center Beijing 100045China

The M6.2 earthquake in Jishishan,Gansu Province,on December 18,2023,caused extraordinary earthquake *** was located in the northern part of the north−south seismic zone,which is a key area for earthquake monitoring in *** newly built dense strong motion stations in this area provide unprecedented conditions for high-precision earthquake relocation,especially the earthquake focal *** paper uses the newly built strong motion and traditional broadband seismic networks to relocate the source locations of the M3.0 and above aftershocks and to invert their focal *** horizontal error of earthquake location is estimated to be 0.5−1 km,and the vertical error is 1−2 *** focal depth range of aftershocks is 9.6−14.6 km,distributed in a 12-km-long strip with SSE *** in the south are more concentrated horizontally and vertically,while aftershocks in the north are more *** focal mechanisms of the main shock and aftershocks are relatively consistent,and the P-axis orientation is consistent with the regional strain *** is a seismic blank area of M3.0 and above,about 3−5 km between the main shock and *** is suggested that the energy released by the main shock rupture is concentrated in this *** on the earthquake location and focal mechanism of the main shock,it is inferred that the Northern Lajishan fault zone is the seismogenic structure of the main shock,and the main shock did not occur on the main fault,but on a secondary *** initial rupture depth and centroid depth of the main shock were 12.8 and 14.0 km,*** source rupture depth may not be the main reason for the severe earthquake disaster.

关键词： Jishishan earthquake earthquake relocation focal mechanism strong motion data

Permeable three-dimensional liquid metal integrated circuits reshaping the next generation of wearable electronics

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Science Bulletin 2024年第20期69卷 3169-3171页

作者： Mengjia Zhu yingying zhang Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China

Wearable electronics are becoming a critical technology in the field of health *** in situ monitoring of physiological information is of great value for preventing and treating high-incidence diseases such as cardiovascular diseases,gastrointestinal diseases,dermatological issues,and neonatal conditions[1–4].However,most flexible wearable sensing devices inevitably need to be connected to extra acquisition equipment and integrated circuits(IC)[5],which do not adequately meet the needs for comfortable *** flexible wearable electronics require stretchable and lightweight backend circuits,and related research is still in its early stages[6–8].

关键词： wear electronics circuits