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Effect of Fe(Ⅲ) on the bromate reduction by humic substances in aqueous solution

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Journal of Environmental Sciences 2008年第3期20卷 257-261页

作者： XIE Li SHANG Chii zhou qi State Key Laboratory of Pollution Control and Resources Reuse Tongji University Shanghai 200092 China Department of Civil Engineering Hong Kong University of Science and Technology Hong Kong 852 China

Humic substances are ubiquitous redox-active organic compounds of environment. In this study, experiments were conducted to determine the reduction capacity of humic acid in the man-ix of bromate and Fe（Ⅲ） solutions and the role of Fe（Ⅲ） in this redox process. The results showed that the humic acid regenerated Fe（Ⅱ） and reduced bromate abiotically. The addition of Fe（Ⅲ） could accelerate the bromate reduction rate by forming humic acid-Fe（Ⅲ） complexes. Iron species acts as electron mediator and catalyst for the bromate reduction by humic acid, in which humic acid transfers electrons to the complexed Fe（Ⅲ） to form Fe（Ⅱ）, and the regenerated Fe（Ⅱ） donate the electrons to bromate. The kinetics study on bromate reduction further indicated that bromate reduction by humic acid-Fe（Ⅲ） complexes is pH dependent. The rate decreased by 2-fold with the increase in solution pH by one unit. The reduction capacity of Aldrich humic acid was observed to be lower than that of humic acid or natural organic matter of Suwanne River, indicating that such redox process is expected to occur in the environment.

关键词： humic acid Fe(Ⅲ) ion bromate reduction electron mediator

Stability of Multiplier Ideal Sheaves

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Chinese Annals of Mathematics,Series B 2022年第5期43卷 819-832页

作者： qi'an GUAN Zhenqian LI Xiangyu zhou School of Mathematical Sciences Peking UniversityBeijing 100871China Siwuge Technology Co.Ltd. Tianfu Life Science ParkChengdu 610093China Institute of Mathematics AMSSand Hua Loo-Keng Key Laboratory of MathematicsChinese Academy of SciencesBeijing100190China

In the present article, the authors find and establish stability of multiplier ideal sheaves, which is more general than strong openness.

关键词： Plurisubharmonic function Multiplier ideal sheaf Strong openness and stability Coherent analytic sheaf L^(2)estimate

Chaotic Motions of the van der Pol-Duffing Oscillator Subjected to Periodic External and Parametric Excitations with Delayed Feedbacks

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Acta Mathematicae Applicatae Sinica 2024年第4期40卷 1111-1126页

作者： Liang-qiang zhou Fang-qi CHEN School of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Chaotic dynamics of the van der Pol-Duffing oscillator subjected to periodic external and parametric excitations with delayed feedbacks are investigated both analytically and numerically in this *** the Melnikov method,the critical value of chaos arising from homoclinic or heteroclinic intersections is derived *** feature of the critical curves separating chaotic and non-chaotic regions on the excitation frequency and the time delay is investigated analytically in *** monotonicity of the critical value to the excitation frequency and time delay is obtained *** is presented that there may exist a special frequency for this *** this frequency,chaos in the sense of Melnikov may not occur for any excitation *** also exists a uncontrollable time delay with which chaos always occurs for this *** simulations are carried out to verify the chaos threshold obtained by the analytical method.

关键词： Van der Pol-Duffing oscillator time delay chaos parametric excitation Melnikov method

Stable high-dimensional solitons in nonlocal competing cubic-quintic nonlinear media

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Communications in Theoretical Physics 2022年第2期74卷 19-27页

作者： qi-ying zhou Hui-jun Li Institute of Nonlinear Physics and Department of Physics Zhejiang Normal UniversityJinhuaZhejiang 321004China

We find and stabilize high-dimensional dipole and quadrupole solitons in nonlocal competing cubic-quintic nonlinear *** adjusting the propagation constant,cubic,and quintic nonlinear coefficients,the stable intervals for dipole and quadrupole solitons that are parallel to the x-axis and those after rotating 45°counterclockwise around the origin of coordinate are *** the dipole solitons and those after rotation,their stability is controlled by the propagation constant,the coefficients of cubic and quintic *** stability of quadrupole solitons is controlled by the propagation constant and the coefficient of cubic nonlinearity,rather than the coefficient of quintic nonlinearity,though there is a small effect of the quintic nonlinear coefficient on the *** proposal may provide a way to generate and stabilize some novel high-dimensional nonlinear modes in a nonlocal system.

关键词： nonlocal media competing cubic-quintic nonlinearity dipole soliton quadrupole soliton

The growth of the screw dislocation of nacreous layer on Pteria penguin

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Science China Earth Sciences 2011年第7期54卷 951-958页

作者： qi LiJian HUANG yiLan zhou Zuyi zhou Zhengyu State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

In response to various environmental factors in offshore South China Sea,a group of microstructures of the screw dislocation are assembled in multiphase screw dislocations on the surface of the nacreous layer of Pteria penguin from the coastal waters of Hainan Island,*** results of the transmission and scanning electronic microscope testing show that organic matter periodically secreted by epithelial histology of mantle of Pteria penguin pre-forms the original screw dislocation growth tem-plate in the form of film,along with its function to select,identify,and adhere to the amorphous calcium carbonate particles as the fine organic venations diffused in the epitaxial screw growth *** the inducement and screw modulation of the or-ganic film and venations,the amorphous calcium carbonate particles gradually evolve into the pseudohexagonal *** microsheet with long-range order and screw dislocation structure by location-selecting tropism and screw dislocation *** micron-scale aragonite microsheets join in the cluster's interactive movement and screw dislocation self-assembly of the organic film,stacking forward along the axis C spirally and forming the nacreous layer with screw dislocation structure.

关键词： Pteria penguin nacreous layer organic film aragonite micro sheet screw dislocation

Patterns and mechanisms of belowground carbon responses to changes in precipitation

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Journal of Plant Ecology 2024年第2期17卷 1-17页

作者： Hongyang Chen qi Zhang Lingyan zhou Xuhui zhou School of Forestry Key Laboratory of Sustainable Forest Ecosystem Management-Ministry ofEducationNortheast Forestry UniversityHarbin 150040China Research Center Shanghai Botanical Garden/Shanghai Engineering Research Center of Sustainable Plant InnovationShanghai 200231China

It is well known that aboveground productivity usually increases with ***,how belowground carbon(C)processes respond to changes in precipitation remains elusive,although belowground net primary productivity(BNPP)represents more than one-half of NPP and soil stores the largest terrestrial C in the *** paper reviews the patterns of belowground C processes(BNPP and soil C)in response to changes in precipitation from transect studies,manipulative experiments,modeling and data integration and *** results suggest the possible existence of nonlinear patterns of BNPP and soil C in response to changes in precipitation,which is largely different from linear response for aboveground productivity.C allocation,root turnover time and species composition may be three key processes underlying mechanisms of the nonlinear responses to changes in precipitation for belowground C *** addition,microbial community structure and long-term ecosystem processes(*** assemblage,soil texture,aggregate stability)may also affect patterns of belowground C processes in response to changes in *** last,we discuss implications and future perspectives for potential nonlinear responses of belowground C processes to changes in precipitation.

关键词： belowground processes BNPP nonlinear precipitation soil C

30 glitches in 18 radio pulsars

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Research in Astronomy and Astrophysics 2021年第7期21卷 1-16页

作者： Hong-yi Liu Shi-qi zhou yu-qi Zhang Zhong-Wen Feng Xia zhou School of Applied Technology XiHua UniversityNanchong 637000China Physics and Space Science College China West Normal UniversityNanchong 637009China

Pulsar timing is a classic technology of detecting irregularities in pulsar *** carried out this method for 18 young radio pulsars,with long-term timing observations obtained between 2007 and 2015 using the Parkes 64-m radio *** a result,30 glitches were identified,ranging from 0.75 × 10^(-9) to 8.6 × 10^(-6) in the relative glitch sizes Δv/v,where v=1/P is the pulse *** glitches are composed of 26 new glitches and four published glitches with new exponential *** pulsars exhibit normal glitches,and six pulsars were observed to undergo a glitch event for the first *** discuss the properties and implications for neutron-star physics of these glitches,and show that they are in agreement with previous work,except that the cumulative probability distributions of the mean waiting times for PSRs J0537-6910,J1341-6220 and J1740-3015 are not in consonance with the Poisson model.

关键词： methods:data analysis stars:neutron pulsars:general

PV Array Reconfiguration Based on the Shaded Cells'Number for PV Modules

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CSEE Journal of Power and Energy Systems 2023年第2期9卷 733-742页

作者： Jun qi Xun Huang Beijia ye Dan zhou College of Information Engineering Zhejiang University of TechnologyHangzhou 310014China

Reconfiguration can increase the output power for a PV array under partial ***,traditional reconfiguration methods consider the PV module as either totally shaded or totally unshaded,and module-based simulation is employed to evaluate the reconfiguration ***,there is an unneglectable error when treating a partially shaded PV module as totally shaded,through using a more accurate cellbased *** on the analysis of the determinant factors on MPPs’power of a PV array,a new reconfiguration method is proposed based on the exact partial shadow shape projected on the PV *** method restructures the electrical connection among PV modules of a PV array according to the shaded cells’number(SCN)of every PV *** cell-based simulations are carried out on a PV array to verify the effectiveness of the proposed SCN-based reconfiguration *** comparisons among various reconfiguration methods and shadow distributions clearly show its suitability to different irregular shadows and its superiority in PV output power enhancement.

关键词： Maximum power point(MPP) partial shadow PV array PV module reconfiguration

Phosphorus-doped NiS_(2)electrocatalyst with a hybrid structure for hydrogen evolution

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Science China(Technological Sciences) 2022年第7期65卷 1506-1512页

作者： zhou qi LIU HaoRui JIAO SunZhi FENG ChenChen State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals Lanzhou University of TechnologyLanzhou 730050China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China College of Mechanical Engineering Longdong UniversityQingyang 745000China

In this article,P-NiS_(2)/Ni_(x)P electrocatalysts were synthesized by dealloying the Ni-Al precursor followed by phosphosulfide *** found that the hybrid structure of P-NiS_(2)/Ni_(x)P provides rich active sites for the surface hydrogen evolution reaction (HER),and the doping of P enhances the electronic conductivity of *** particular,the obtained electrode shows a low overpotential of 196 mV at 10 mA cm^(-2)and a small Tafel slope of only 110 mV dec^(-1)in the ***,longterm constant current electrolysis test experiments indicate that P-NiS_(2)/Ni_(x)P has good service *** research will help to open a new window on the design and fabrication of HER electrocatalysts.

关键词： nickle phosphosulfides hybrid structure hydrogen evolution reaction dealloying