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Unravelling the effects of complexation of transition metal ions on the hydroxylation of catechol over the whole pH region

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Journal of Environmental Sciences 2022年第5期34卷 392-402页

作者： Zexiu An Jianfei Sun Qiong Mei BoWei Mingxue Li ju xie Maoxia He Qiao Wang Environment Research Institute Shandong UniversityQingdao 266237China School of Environmental and Materials Engineering Yantai UniversityYantai 264005China College of Safety and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China

Catechol pollutants(CATPs)serving as chelating agents could coordinate with many metal ions to form various CATPs-metal *** information is available on the effects of complexation of metal ions on CATPs *** work presents a systematical study of·OH-mediated degradation of catechol and catechol-metal complexes over the whole pH range in advanced oxidation processes(AOPs).Results show that the pH-dependent complexation of metal ions(Zn^(2+),Cu^(2+),Ti^(4+)and Fe^(3+))promotes the deprotonation of catechol under neutral and even acidic *** radical adduct formation(RAF)reactions are both thermodynamically and kinetically favorable for all dissociation and complexa-tion species,and-OH/-O-group-containing C positions are more vulnerable to·OH *** kinetic results show that the complexation of the four metal ions offers a wide pH range of effectiveness for catechol *** pH 7,the apparent rate constant(k_(app))values for different systems follow the order of catechol+Ti^(4+)≈catechol+Zn^(2+)>catechol+Cu^(2+)>catechol+Fe^(3+)>*** mechanistic and kinetic results would greatly improve our understanding of the degradation of CATPs-metal and other organics-metal complexes in *** toxicity assessment indicates that the·OH-based AOPs have the ability for decreasing the toxicity and increasing the biodegradability during the processes of catechol degradation.

关键词： Catechol Metal ions Complexation pH Degradation

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Electromagnetic form factors of neutron and neutral hyperons in the oscillating point of view

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Chinese Physics C 2022年第7期46卷 41-46页

作者： An-Xin Dai Zhong-Yi Li Lei Chang ju-jun xie Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 China School of Nuclear Science and Technology University of Chinese Aeademy of SciencesBeijing 101408China School of Physics Nankai UniversityTijin 300071China School of Physics and Microelectronics Zhengzhou UniversityZhengzhouHenan 450001China Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu ProvinceLanzhou UniversityLanzhou 730000China

Based on the recent precise measurements by the BESIII collaboration for electron–positron annihilation into a neutron and antineutron pair,the effective form factors of the neutron were determined in the time-like region,and it was found that the effective form factors of the neutron are smaller than those of the *** effective form factors of the neutron show a periodic behaviour,similar to those of the ***,a comparative analysis forΛ,∑^(0)and■hyperons is *** of the available data on the effective form factors ofΛ,∑^(0)and■with zero charge show an interesting phenomenon in the oscillating behavior of their effective form ***,this will need to be confirmed by future precise *** theoretical and experimental investigations of this phenomenon can shed light on the reaction mechanisms of the electron–positron annihilation processes.

关键词： electromagnetic form factors baryon-antibaryon pair production electron-positron annihilation

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Numerical study on erosion behavior of sliding sleeve ball seat for hydraulic fracturing based on experimental data

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Petroleum Science 2023年第1期20卷 515-525页

作者： Xuan-Li Zhou Yan-Bao Guo Qiu-ju xie De-Guo Wang Hyun C.Yoon College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China Harold Vance Department of Petroleum Engineering Texas A&M UniversityCollege StationTX77843United States Korea Institute of Geoscience and Mineral Resources Daejeon34132South Korea

The sleeve sealing ball seat is one of the important components in the multistage fracturing process of horizontal *** erosion and wear of the surface will decrease the sealing performance of the fracturing ball and the ball *** leads to pressure leakage during the fracturing process and fracturing *** this paper,combined with the actual ball seat materials and working conditions during the fracturing process,the erosion tests of ductile iron and tungsten carbide materials under different erosion speeds,angles,and mortar concentrations are carried *** the erosion test results were analyzed by mathematical fitting,and a set of erosion models suitable for sliding sleeve setting ball seat materials were innovatively *** the first time,this paper combines the erosion model obtained from the experiment and the computational fluid dynamics(CFD)with Fluent software to simulate the erosion of the ball *** on the simulation results,the morphology of the sliding sleeve seat ball after erosion is *** analysis of the test and simulation results,it is showed that the erosion rate of tungsten carbide material is lower and the wear resistance is better under the condition of small angle *** research can offer a strong basis for fracturing site selection,surface treatment methods,and prediction of failure time of ball seats.

关键词： Multistage fracturing Sliding sleeve ball seat Erosion wear Erosion model Fluent simulation

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Role of the Λ(1600) in the K^-p→Λπ^0π^0 reaction

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Communications in Theoretical Physics 2020年第4期72卷 64-70页

作者： He Zhou ju-jun xie Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBejing 101408China School of Physics and Microelectronics Zhengzhou UniversityZhengzhouHenan 450001China

Role of theΛ(1600)is studied in the K^-p→Λπ^0π^0 reaction by using the effective Lagrangian approach near the *** perform a calculation for the total and differential cross sections by considering the contributions from theΛ(1600)andΛ(1670)intermediate resonances decaying intoπ^0∑^*0(1385)with∑^*0(1385)decaying intoπ^0Λ.Additionally,the non-resonance process from u-channel nucleon pole is also taken into *** our model parameters,the current experimental data on the total cross sections of the K^-p→Λπ^0π^0 reaction can be well *** is shown that we really need the contribution from the A(1600)with spin-parity J^P=1/2^+,and that these measurements can be used to determine some of the properties of theΛ(1600)***,we also plot theπ0Λinvariant mass distributions which could be tested by the future experimental measurements.

关键词： KN scattering effective Lagrangian approach hyperon resonance

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金荞麦化学成分、药理作用的研究进展及质量标志物(Q-Marker)的预测分析

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广州化工 2024年第8期52卷 96-98,128页

作者：赵永恒陈成杨思艳谢菊芳谢秋雨郝新才王佰灵湖北医药学院药学院武当特色中药研究湖北省重点实验室/湖北省药用植物综合利用工程技术研究中心湖北十堰442000

金荞麦是我国传统中药材,主要含有黄酮类、三萜类、甾体类、有机酸类等化学成分,具有抗炎、抗肿瘤、降血糖、抗氧化等多种药理活性。通过文献检索,梳理了近几年国内外对金荞麦化学成分及药理作用研究,从传统功效、传统药性、化学成分可... 详细信息

金荞麦是我国传统中药材,主要含有黄酮类、三萜类、甾体类、有机酸类等化学成分,具有抗炎、抗肿瘤、降血糖、抗氧化等多种药理活性。通过文献检索,梳理了近几年国内外对金荞麦化学成分及药理作用研究,从传统功效、传统药性、化学成分可测性、不同产地等多个方面对其质量标志物(Q-Marker)进行了预测分析,为金荞麦质量控制提供科学依据。

关键词：金荞麦黄酮类萜类甾体类质量标志物

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The Three-Pion Decays of the a1(1260)

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Communications in Theoretical Physics 2018年第7期69卷 60-66页

作者： Xu Zhang ju-jun xie Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of SciencesBeijing 101408China

We investigate the decay of a_1^+(1260) →π^+π^+π^-with the assumption that the a_1(1260) is dynamically generated from the coupled channel ρπ and KK~*interactions. In addition to the tree level diagrams that proceed via a_1^+(1260) →ρ~0π^+→π^+π^+π^-, we take into account also the final state interactions of ππ→ππ and KK →ππ. We calculate the invariant π^+π^-mass distribution and also the total decay width of a_1^+(1260) →π^+π^+π^-as a function of the mass of a_1(1260). The calculated total decay width of a_1(1260) is significantly different from other model calculations and tied to the dynamical nature of the a_1(1260) resonance. The future experimental observations could test of model calculations and would provide vary valuable information on the relevance of the ρπ component in the a_1(1260) wave function.

关键词： effective Lagagian approach axial-vector meson final state interactions

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Electromagnetic form factors of Σ^(+) and Σ^(-) in the vector-meson dominance model

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Communications in Theoretical Physics 2021年第5期73卷 66-70页

作者： Zhong-Yi Li ju-jun xie Institute of Modem Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 101408China School of Physics and Microelectronics Zhengzhou UniversityZhengzhouHenan 450001China

Based on the recent measurements of the e^(+)e^(-)→∑^(+)∑^(-)^(-)and e^(+)e^(-)→∑^(-)∑^(-)^(+)processes by the Beijing SpectrometerⅢ(BESⅢ)collaboration,the electromagnetic form factors of the hyperon Σ^(+) and Σ^(-) in the timelike region are investigated using the vector-meson dominance model,where the contributions of theρ,ω,and φ mesons are taken into *** model parameters are determined from the BESⅢexperimental data of the timelike effective form factors|G_(eff)|of the Σ^(+) and Σ^(-) baryons for center-of-mass energies from 2.3864 to 3.02 *** is found that we can provide quantitative descriptions of the available data using as few as one adjustable model *** then progress to an analysis of the electromagnetic form factors in the spacelike region and evaluate the spacelike form factors of the hyperons Σ^(+) and Σ^(-).The electromagnetic form factors obtained for the Σ^(+) and Σ^(-) baryons are comparable with those of other model calculations.

关键词： Electromagnetic form factors Vector-meson dominance Hyperon–antihyperon pair production

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Study of the a1（1260） resonance in the γp→π+π+π-n reaction

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Chinese Physics C 2019年第6期43卷 45-50页

作者： Xu Zhang ju-jun xie Institute of Modem Physics Chinese Academy of Sciences Lanzhou 730000 China University of Chinese Academy of Sciences Beijing 101408 China

Within an effective Lagrangian approach and resonance model, we study the γp→a1（1260）+n andγp→π+π+π-n reactions via the π-exchange mechanism. For the γp →π+π+π-n reaction, we perform a calculation of the differential and total cross-sections by considering the contributions of the a1（1260） intermediate resonance decaying into per and then into π+π+π-. Besides,the non-resonance process is also considered. With a lower mass of a1（1260）, the experimental data for the invariant π+π+π-mass distributions can be fairly well reproduced. For theγp→a1（1260）+n reaction, with the model parameters, the total cross-section is of the order of 10 μb at the photon beam energy Eγ2.5 GeV. It is expected that the model calculations in this work could be tested by future experiments.

关键词： photoproduction mass distributions total cross-section a1(1260)

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Styrax japonicus functional genomics:an efficient virus induced gene silencing(VIGS)system

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Horticultural Plant Journal 2024年第1期10卷 252-258页

作者： Gangyu Sun Yiqian ju Cuiping Zhang Lulu Li Xinqiang Jiang Xiaoman xie Yizeng Lu Kuiling Wang Wei Li College of Landscape Architecture and Forestry Qingdao Agricultural UniversityQingdaoShandong 266109China Shandong Provincial Center of Forest and Grass Germplasm Resources JinanShandong 250102China

VIGS(Virus-induced gene silencing),a method for posttranscriptional gene silencing,is an effective technique for investigating the activities of genes in *** there is no report for available VIGS system in Styrax japonicus,the application of a VIGS approach that results in a gene knockdown to study gene function is *** this study,we compared the characteristics that could affect the viability of VIGS in ***,including the acetosyringone(AS)concentration,the Agrobacterium’s optical density and the inoculation *** stable reference genes of *** were selected to validate the gene’s knockdown by quantitative *** a result,we successfully constructed 2 VIGS systems based on TRV virus:vacuum with AS concentration of 200μmol·L^(-1)and OD600of 0.5,and friction-osmosis with AS concentration of 200μmol·L^(-1)and OD600of 1.0,which silencing efficiency was 83.33%and 74.19%,*** successfully applied VIGS method provides a rapid and effective reverse gene functional analysis approach in *** to identify unknown gene functions.

关键词： Styrax japonicus VIGS Reference gene

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Effect of Calcium Oxide Additive on the Performance of Iron Oxide Sorbent for High-Temperature Coal Gas Desulfurization

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Journal of Natural Gas Chemistry 2007年第4期16卷 404-408页

作者： Huiling Fan Kechang xie ju Shangguan Fang Shen Chunhu Li Education and Shanxi Province Taiyuan University of Technology Taiyuan 030024 Shanxi China

The effect of calcium oxide additive in iron oxide sorbent for hot gas desulfurization was investigated by XRD and TPR *** characterization showed that CaO was highly dispersed after the calcination of *** sulfate formed in the desulfurization was decomposed and regenerated to CaO by reacting with CO before the next sulfidation *** participated in every sulfidation/regeneration cycle and contributed to the enhancement of sulfur *** TPR results showed that the reduction temperature of the sorbent increased with the increase of the content of *** played a role of retarding ***,the addition of calcium oxide additive will benefit the utilization of iron oxide sorbent in strongly reducing atmospheres.

关键词： calcium oxide iron oxide sorbent high temperature desulfurization

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