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On the Dynamics of the Singularly Perturbed Rational Maps

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Acta Mathematica Sinica,English Series 2010年第2期26卷 265-276页

作者： Lian rong ding Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 P. R. China

In this paper, we study the dynamics of the family of rational maps fλ,（z） = zn - λ/zm, n ≥2, m ≥ 1,λ ∈ C. We construct an example of buried Sierpinski curve Julia set in this family. We also give an estimate ... 详细信息

关键词： Julia set Sierpinski curve bifurcation locus

Baeyer–Villiger oxidation of cyclohexanone catalyzed by cordierite honeycomb washcoated with Mg–Sn–W composite oxides

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Chinese Journal of Chemical Engineering 2019年第3期27卷 564-574,F0004页

作者： Yang Han Shengnan Li rong ding Wenjin Xu Guangxu Zhang School of Chemistry Chemical Engineering and Life Science Wuhan University of Technology

In this work, a series of Mg–Sn–W oxide powder catalysts with different tungsten oxide contents(0, 15 wt% and 30 wt%) were prepared and washcoated on cordierite honeycomb monoliths to produce monolithic catalysts,which were tested for the Baeyer–Villiger oxidation of cyclohexanone. The obtained monolithic catalysts,which combined the advantages of both homogeneous and heterogeneous catalysts, showed high catalytic efficiency and overcame the problems of product separation that occurred in the homogeneous catalytic *** and EDX tests showed that the catalytic coating, with a thickness of approximately 20 μm, was compact and homogeneous, and an enlarged BET surface area was indicated by N_2 adsorption–desorption compared with the bare cordierite honeycomb. The chemical properties on the catalytic surface of the powder and monolithic catalysts were characterized by XPS, which indicated the tin and tungsten on the catalysts exhibited their full oxide states and presented mainly as stannate and tungstate, as confirmed by XRD and FTIR ***, the catalytic activity test indicated that the tungsten content of the catalysts played an important role in catalytic efficiency and that monolithic catalysts were produced without obvious catalytic activity loss compared with the corresponding powders.(M)W30, which exhibited excellent mechanical stability and maintained high activity after recycling three times, was the optimal catalyst, showing a high selectivity that exceeded 86%and a conversion above 64%. Therefore, the structured Mg–Sn–W oxide catalysts have great potential for application in practical production.

关键词： Baeyer–Villiger oxidation Monolith Mg–Sn–W oxide catalysts Synthesis ε-Caprolactone

2022 Monkeypox outbreak:Why is it a public health emergency of international concern?What can we do to control it?

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World Journal of Clinical Cases 2022年第30期10卷 10873-10881页

作者： Shi-Yan Ren Jing Li rong-ding Gao Department of Laser and Vascular Surgery Aviation General HospitalChina Medical UniversityBeijing 100012China Department of Infectious Disease Aviation General HospitalChina Medical UniversityBeijing 100012China

The World Health Organization(WHO) called the recent monkeypox(MPX)outbreak a Public Health Emergency of International Concern on July 23,*** United States of America(US) alarmed the recent MPX outbreak as the US public health emergency on August 4,*** early May 2022,more than 35000 MPX cases and 12 deaths had been reported to WHO from 92 countries and territories by August 17,2022,and MPX cases continue rising rapidly with improved surveillance,access to diagnosis,and continuous virus spreading *** 99% MPX cases are men,of which 95% cases are men who have sex with *** evidence of MPX being sexually transmitted infections(STIs) is found;however,a high percentage(25%) of concurrent STIs and frequent anogenital symptoms suggest transmission through local inoculation during close intimate contact or sexual *** approaches including a comprehensive international vaccination strategy and adequate supplies are mandatory to prevent MPX ***,vaccination,MPX scrutiny and careful monitoring,and crossborder collaborations with international sectors are practical strategy to contain MPX *** are educated to reduce the risk of exposure and to reduce the number of sexual partners especially new ones,to avoid contacting travelers from epidemic regions or animals that may carry MPX virus,and avoid traveling to endemic areas.

关键词： Monkeypox Outbreak Public Health Emergency of International Concern vaccination Infectivity Transmission Man who have sex with man

Electrostatic generator enhancements for powering IoT nodes via efficient energy management

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Microsystems & Nanoengineering 2024年第2期10卷 143-152页

作者： Zibo Wu Zeyuan Cao Junchi Teng rong ding Jiani Xu Xiongying Ye State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua University100084BeijingChina

Electrostatic generators show great potential for powering widely distributed electronic devices in Internet of Things(IoT)***,a critical issue limiting such generators is their high impedance mismatch when coupled to electronics,which results in very low energy utilization ***,we present a high-performance energy management unit(EMU)based on a spark-switch tube and a buck converter with an RF *** optimizing the elements and parameters of the EMU,a maximum direct current output power of 79.2 mW m^(-2)rps^(-1)was reached for a rotary electret generator with the EMU,achieving 1.2 times greater power output than without the ***,the maximum power of the contact-separated triboelectric nanogenerator with an EMU is 1.5 times that without the *** excellent performance is attributed to the various optimizations,including utilizing an ultralow-loss spark-switch tube with a proper breakdown voltage,adding a matched input capacitor to enhance available charge,and incorporating an RF inductor to facilitate the high-speed energy transfer *** on this extremely efficient EMU,a compact self-powered wireless temperature sensor node was demonstrated to acquire and transmit data every 3.5 s under a slight wind speed of 0.5 m/*** work greatly promotes the utilization of electrostatic nanogenerators in practical applications,particularly in IoT nodes.

关键词： IoT power generator

Present status and future prospect of design of Pt-cerium oxide electrodes for fuel cell applications

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Progress in Natural Science:Materials International 2012年第6期22卷 561-571页

作者： Toshiyuki Mori ding rong Ou Jin Zou John Drennan Graduate School of Chemical Sciences and Engineering.Hokkaido University Kita13Nishi8Kita-ku.Sapporo.Hokkaido 060-8628.Japan Hetero interface design group.Global Research Center for Environment and Energy based on Nanomaterials Science(GREEN).National Institute for Materials Science.1-1 Namiki Tsukuba.Ibaraki 305-0044.Japan Centre for Microscopy and Microanalysis The University of QueenslandSt.LuciaBrisbaneQld 4072Australia Laboratory of Fuel Cells Dalian Institute of Chemical Physics Chinese Academy of Sciences457 Zhongshan RoadDalian

In the research field of proton exchange membrane fuel cells,the design of electrocatalytic activities on Pt-oxide promoter in the anode side has attracted attention for improvement of CO tolerance of Pt in anode side and a lowering of large over-potential loss of the oxygen reduction reaction on the cathode in the fuel *** the Pt-oxide promoter series,Pt-CeOx/C is one of the unique *** is because the unique behavior of CeOxsuch as electrochemical redox reaction between Ce3+and Ce4+in the anodic and cathodic reactions of fuel cell is *** present short review gives an overview of the recent works for improvement of the CO tolerance of Pt in the Pt-CeOx/C anodes and enhancement of the oxygen reduction reaction activity on Pt in the Pt-CeOx/C cathodes for fuel cell *** show the design paradigm for fabrication of high quality Pt-CeOx/C electrodes,the authors re-introduced parts of our research results to highlight the important role of interface structure of Pt-CeOxbased on the ultimate analysis results. The usefulness of the combined approach of microanalysis and the processing route design is presented.

关键词： Pt-CeO_x electrode CO tolerance of Pt Oxygen reduction reaction Interface of Pt and cerium oxide Microanalysis

Fear can be more harmful than the severe acute respiratory syndrome coronavirus 2 in controlling the corona virus disease 2019 epidemic

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World Journal of Clinical Cases 2020年第4期8卷 652-657页

作者： Shi-Yan Ren rong-ding Gao Ye-Lin Chen Vascular Surgery Department of General SurgeryAviation General HospitalChina Medical UniversityBeijing 100012China College of Robotics Beijing Union UniversityBeijing 100101China

The current corona virus disease 2019 outbreak caused by severe acute respiratory syndrome coronavirus 2 started in Wuhan,China in December 2019 and has put the world on *** safeguard Chinese citizens and to strengthen global health security,China has made great efforts to control the *** in the global community have joined China to limit the ***,discrimination and prejudice driven by fear or misinformation have been flowing globally,superseding evidence and jeopardizing the anti-severe acute respiratory syndrome coronavirus 2 *** analyze this phenomenon and its underlying causes and suggest practical solutions.

关键词： Coronavirus Severe acute respiratory syndrome Severe acute respiratory syndrome coronavirus 2 Coronavirus disease 2019 Outbreak Fear Discrimination Prejudice

Multicolor Optical Monitoring of the γ-Ray Emitting Narrow-line Seyfert 1 Galaxy PMN J0948+0022 from 2020 to 2021

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Research in Astronomy and Astrophysics 2022年第7期22卷 60-72页

作者： Yu-Xin Xin ding-rong Xiong Jin-Ming Bai Hong-Tao Liu Kai-Xing Lu Ji-rong Mao Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China

In order to study the physical properties of the γ-ray emitting narrow-line Seyfert 1(NLS1) galaxy population,photometric and spectral observations of the γ-ray emitting NLS1 PMN J0948+0022 were made with the Lijiang2.4 m optical telescope of Yunnan Observatories,Chinese Academy of *** data in the B and R bands were collected for 50 nights from 2020 January to 2021 *** the observation epoch,the variability amplitudes are 73.67% in the B band and 79.96% in the R ***-day variability is found in two observation nights,and the duty cycle value is 29% with variability amplitude> 12.9% in the R band,which support the presence of the relativistic jets in the *** redder-when-brighter(RWB) chromatic trend(or steeper-when-brighter trend) appears on intra-day and long *** RWB trend is dominated by the radiation of accretion disk and jet,and resembles those in flat spectrum radio *** PMN J0948+0022 is brighter than 17.5 in the R band,there is no color change *** analyzing the spectral data of PMN J0948+0022,we obtained the black hole mass of M.=1.61×10^(7) Mand accretion rate of M=93,and confirmed that PMN J0948+0022 is a super-Eddington accreting *** redshifts of reverberation mapped super-Eddington accreting active galactic nuclei can be expanded by PMN J0948+0022 up to above ***-Eddington accreting NLS1 galaxies were chosen as a new type of cosmological candle in the *** J0948+0022 may be used as a target for the next step of reverberation mapping monitoring project of super-Eddington accreting massive black holes.

关键词： galaxies:jets galaxies:photometry galaxies:Seyfert galaxies:active

Existence and Blow-up of Smooth Solutions for Cahn-Hilliard Equation with Inertial Term

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Journal of Donghua University(English Edition) 2019年第4期36卷 413-420页

作者： ding rong WU Zhigang College of Science Donghua University

The motivation of this paper is to systematically study how the inertial term affects the behavior of the solution of the Cahn-Hilliard *** there is an inertial term,the equation becomes a parabolic-hyperbolic *** overcome the difficulties from large perturbation and the hyperbolicity,a few elaborate energy estimates should be given,which are based on choosing suitable space of the smooth solution,even some inequalites in negative Sobolev *** precisely,for 1-dimensional(1D)non-viscous case and 1D,2D,and 3D viscous case,the global existence of the smooth solutions are ***,several blow-up results are established by using the convex *** results exhibit the interplay between the viscosity and the inertial term for the behavior of the smooth solution.

关键词： Cahn-Hilliard equation with inertial term existence blow-up

Study on the Microscopic Network Model of PVA Hydrogel Based on the Tensile Behavior

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Acta Mechanica Solida Sinica 2019年第5期32卷 663-674页

作者： Kejia Xu Liqun Tang Yongrou Zhang rong ding Xinyuan Wang Dafei Huang Jiansheng Lin School of Civil Engineering and Transportation South China University of TechnologyGuangzhouChina Guangdong Institute of Intelligent Manufacturing GuangzhouChina

Hydrogel is an emerging material widely used in the biological *** tensile properties of hydrogel mainly depend on its polymer network,but due to the complex microstructure of the network,some properties of the hydrogel have yet to be qua nt itatively *** this article,we built a three-dimensional random fiber net work to characterize the micros tructure of a *** fibers were simplified as elastic beams,and the cross-links were regarded as"hinges."Combined with the macroscopic experimental results,the influence of the change of fiber length and the relationship between the polymer content and the cross-link density were *** model was verified by the quasi-static tensile test results of real PVA hydrogel materials with different fiber *** results show that the model can well match the tensile stress-strain curve and tensile strength of the PVA hydrogels with different fiber *** change in micros true ture of the fiber network induces nonlinear behaviors,and although the cross-link number increases with the increase in polymer content,the cross-link density(per unit PVA chain length)of the PVA hydrogel slightly decreases as the content increases.

关键词： PVA hydrogel Micro-model Tensile behavior Fiber network