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Science China Chemistry 2015年第11期58卷 1674-1694页

作者： jiaxing Zhang Guowei Wang State Key Laboratory of Molecular Engineering of Polymers Collaborative Innovation Center of Polymers and Polymer Composite Materials Department of Macromolecular Science Fudan University

Because glycidyl(Gly) contains an epoxy and an active hydroxyl group, the Gly unit is difficult to introduce into certain polymeric chains in a controlled manner and usually yields hyperbranched polyglycidyl. Alternatively, the monomer 1-ethoxyethyl glycidyl ether(EEGE), derived from Gly and ethyl vinyl ether, has shown potential for application in polymer chemistry, and homopolymerization of this monomer directly produces linear poly(1-ethoxyethyl glycidyl ether) and further yields linear polyglycidyl. In this review, the initiation system of the EEGE monomer is first discussed in terms of chain transfer to monomers in ring-opening polymerization of epoxides with substituent groups. Then, random copolymerization of EEGE with other epoxides is considered. In addition, because the EEGE units on polymers can be transferred to Gly units and further used to construct copolymers with complicated architectures, the applications of EEGE monomers to block, graft, and hyperbranched copolymers are reviewed. Finally, the synthesis of main chain and terminal functional polyethers by transforming the hydroxyl groups at the polymer end or on the main chain into certain functional groups are also discussed. Chemistry based on EEGE has been proved to be an efficient, versatile route to constructing copolymers containing Gly units and ultimately yielding the target properties and applications.

关键词： linear polyglycidyl (LPG) poly(1-ethoxyethyl glycidyl ether) (PEEGE) block polymer graft polymer hyper-branched polymer

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围压下凝灰岩力学特征和脆性指数变化规律

长江大学学报（自然科学版） 2019年第1期16卷 29-33,I0002,I0003页

作者：张立刚谭甲兴闫立鹏刘照义李士斌曲思凝东北石油大学石油工程学院黑龙江大庆163318 中石化石油工程技术研究院北京100101

围压下凝灰岩力学特征和脆-延性评价对指导该类火成岩气藏的高效开发有重要意义。以松辽盆地北部深层凝灰岩为研究对象,基于常规三轴压缩试验和Mohr-Coulomb强度准则,研究了其在不同围压下的强度、变形参数、破坏特征及脆-延性转换机制... 详细信息

围压下凝灰岩力学特征和脆-延性评价对指导该类火成岩气藏的高效开发有重要意义。以松辽盆地北部深层凝灰岩为研究对象,基于常规三轴压缩试验和Mohr-Coulomb强度准则,研究了其在不同围压下的强度、变形参数、破坏特征及脆-延性转换机制。研究结果表明,随着围压增加,凝灰岩的强度显著增加,变形能力增强,破坏前段凝灰岩经历了塑弹性-弹性-弹塑性转变,破坏后应变软化特性逐渐减弱;与峰值强度曲线相比,残余强度曲线斜率更高,随着围压增加,两者趋于闭合;随着围压增加,脆性指数呈指数函数形式减小,由脆性向延性转变。该研究成果为钻井和压裂等工程设计提供了基础依据。

关键词：凝灰岩三轴压缩试验力学特性脆-延性转换临界围压

Plasma-facilitated modification of pumpkin vine-based biochar and its application for efficient elimination of uranyl from aqueous solution

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Plasma Science and Technology 2019年第9期21卷 101-109页

作者： Jinxin YI Zhipeng HUO Xiaoli tan Changlun CHEN jiaxing LI Key Laboratory of Photovolatic and Energy Conservation Materials Institute of Plasma Physics Chinese Academy of Sciences Hefei 230031 People's Republic of China University of Science and Technology of China Hefei 230026 People's Republic of China School of Environment and Chemical Engineering North China Electric Power University Beijing 102206 People's Republic of China Chemistry Department Faculty of Science King Abdulaziz University Jeddah 21589 Saudi Arabia

An acrylic modified pumpkin vine-based biochar(p-PVB-PAA) is synthesized by non-thermal plasma-grafting modification of pumpkin vine-based biochar(PVB) for the removal of uranyl from an aqueous solution. Microscopic characterization reveals that compared to PVB the surface of p-PVBPAA has more oxygen-containing functional groups by strong chemical bonding and the specific surface area is increased to 275.3 m^2 g^-1 from 3.8 m^2g^-1. It is found that p-PVB-PAA showed a much higher maximum adsorption capacity for uranyl from aqueous solutions than PVB, which were207.02 mg g^-1 and 67.58 mg g^-1 at pH=5 and 298 K, respectively. Moreover, the adsorption behavior follows a pseudo-second-order kinetics model and the Langmuir adsorption ***, macroscopic experiments and spectroscopic studies verified that the significantly improved adsorption performance of the p-PVB-PAA is due to surface complexation and electrostatic interactions. Furthermore, the very high removal efficiency and excellent regeneration ability(the percentage of the removal still remained at nearly 90% after five cycles) makes this low-cost, easily obtained, and environmentally friendly material attractive for commercial application.

关键词： biochar modification plasma treatment adsorption uranyl

Distribution of reactive aluminum under the influence of mesoscale eddies in the western South China Sea

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Acta Oceanologica Sinica 2017年第6期36卷 95-103页

作者： LIU jiaxing ZHOU Linbin tan Yehui WANG Qionga HU Zifeng LI Jiajun JIANG Xin KE Zhixin Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Guangdong Provincial Key Laboratory of Applied Marine Biology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China University of Chinese Academy of Sciences Beijing 100049China

To understand the distribution of aluminum （A1） under the influence of mesocale eddies in the western South China Sea （SCS）, sea level anomaly, geostrophic current, environmental parameters and reactive A1 were investigated in the western SCS in August 2013. The highest reactive A1 concentration （（180±64） nmol/L） was observed in the surface waters, indicating a substantial atmospheric input. Vertically, the reactive A1 decreased from the surface high concentration to the subsurface minima at the depth of chlorophyll a （Chl a） maxima and then increased again with depth at most of the stations. The average concentration of reactive A1 in the upper 100 m water column was significantly lower in the cyclonic eddy （（137±6） nmol/L） as compared with that in the non- eddy waters （（180±21） nmol/L）. By contrast, the average concentrations of Chl a and silicate in the upper 100 m water column were higher in the cyclonic eddy and lower in the anticyclonic eddy. There was a significant negative correlation between the average concentrations of reactive Al and Chl a in the upper 100 m water column. The vertical distribution of reactive AI and the negative correlation between reactive A1 and Chl a both suggest that the reactive A1 in the upper water column was significantly influenced by biological removal processes. Our results indicate that mesoscale eddies could regulate the distribution of reactive A1 by influencing the primary production and phytoplankton community structure in the western SCS.

关键词： reactive aluminum mesoscale eddy chlorophyll a biological removal phytoplankton primaryproduction western South China Sea

Boundary Holder Estimates for a Class of Degenerate Elliptic Equations in Piecewise Smooth Domains

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Chinese Annals of Mathematics,Series B 2022年第5期43卷 719-738页

作者： jiaxing HONG Genggeng HUANG School of Mathematical Sciences Fudan UniversityShanghai 200433China

In this paper, the authors will apply De Giorgi-Nash-Moser iteration to establish boundary H?lder estimates for a class of degenerate elliptic equations in piecewise C^(2)-smooth domains.

关键词： Degenerate elliptic De Giorgi-Nash-Moser iteration Boundary Holder regularity

Infinitesimal nonrigidity of convex surfaces with planar boundary

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Science China Mathematics 2005年第4期48卷 513-521页

作者： LI Chunhe HONG jiaxing Institute of Mathematics Fudan University Shanghai200433 China Institute of Mathematics Fudan University Shanghai200433 China

In the present paper infinitesimal nonrigidity of a class of convex surfaces with planar boundary is given. This result shows that if the image of the Gauss map of an evolution convex surface with planar boundary covers some hemisphere, this surface may be of infinitesimal nonrigidity for the isometric deformation of planar boundary.

关键词： infinitesimal nonrigidity, convex surface, planar boundary.

Performance analysis of diffusion-based decode-and-forward relay with depleted molecule shift keying

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Digital Communications and Networks 2021年第3期7卷 399-409页

作者： jiaxing Wang Mugen Peng Yaqiong Liu State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing100876China School of Electronic and Control Engineering North China Institute of Aerospace Engineering.Langfang Aerospace Testing Technology and Instrument Research and Development CenterLangfang065000China

The distance-decay effect of molecular signals makes communication range a major challenge for diffusion-based Molecular Communication(MC).To solve this problem,the intermediate nano-machine is deployed as a relay between the transmitter and its intended receiver *** this work,we employ the Depleted Molecule Shift Keying(D-MoSK)to model a Decode-and-Forward(DF)relay communication *** closed-form expression of Bit Error Rate(BER)for the concerned DF relay with D-MoSK is ***,the maximum a posteriori probability,minimum error probability,and maximum likelihood schemes are formulated for data *** relationships between BER and other key parameters,including the number of released molecules,receiving radius,and relay position,are investigated in *** results show that the proposed scheme can improve communication reliability ***,the performance gain can be maximized by optimizing the position of the relay and the receiving radius.

关键词： Diffusion Molecular communication Decode-and-Forward relay Bit error rate

Aerodynamic-Parameter Identification and Attitude Control of Quad-Rotor Model with CIFER and Adaptive LADRC

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Chinese Journal of Mechanical Engineering 2021年第2期34卷 150-159页

作者： Sen Yang Leiping Xi jiaxing Hao Wenjie Wang Department of UAV Engineering Army Engineering UniversityShijiazhuang 050003China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China School of Electrical and Electronic Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

Current research on quadrotor modeling mainly focuses on theoretical analysis methods and experimental methods,which have problems such as weak adaptability to the environment,high test costs,and long ***,the PID controller,which is currently widely used in quadrotors,requires improvement in ***,the aforementioned research has considerable practical significance for the modeling and controller design of quadrotors with strong coupling and nonlinear *** the present research,an aerodynamic-parameter estimation method and an adaptive attitude control method based on the linear active disturbance rejection controller(LADRC)are designed ***,the motion model,dynamics model,and control allocation model of the quad-rotor are established according to the aerodynamic theory and Newton-Euler ***,a more accurate attitude model of the quad-rotor is obtained by using a tool called CIFER to identify the aerodynamic parameters with large uncertainties in the frequency ***,an adaptive attitude decoupling controller based on the LADRC is designed to solve the problem of the poor anti-interference ability of the quad-rotor and adjust the key control parameter b0 automatically according to the change in the moment of inertia in real ***,the proposed approach is verified on a semi-physical simulation platform,and it increases the tracking speed and accuracy of the controller,as well as the anti-disturbance performance and robustness of the control *** paper proposes an effective aerodynamic-parameter identification method using CIFER and an adaptive attitude decoupling controller with a sufficient anti-interference ability.

关键词： Quad-rotor Qarameters identification CIFER Adaptive LADRC

Effects and mechanisms of acupuncture on women related health

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Frontiers of Medicine 2024年第1期18卷 46-67页

作者： Huichao Qin jiaxing Feng Xiaoke Wu Department of Reproductive Medicine Heilongjiang Provincial HospitalHarbin Institute of TechnologyHarbin150036China Department of Obstetrics and Gynecology First Affiliated HospitalHeilongjiang University of Chinese MedicineHarbin150040China

Globally,public health interventions have resulted in a 30-year increase in women’s life ***,women’s health has not increased when socioeconomic status is ***’s health has become a major public health concern,for those women from developing countries are still struggling with infectious and labor-related diseases,and their counterparts in developed countries are suffering from physical and psychological *** recent years,complementary and alternative medicine has attracted wide attentions with regards to maintaining women’s ***,a crucial component of traditional Chinese medicine,has been used to treat many obstetric and gynecological diseases for thousands of years due to its analgesic and anti-inflammatory effects and its effects on stimulating the sympathetic/parasympathetic nervous *** fully understand the mechanism through which acupuncture exerts its effects in these diseases would significantly extend the list of available interventions and would allow for more reasonable advice to be given to general ***,by searching PubMed and CNKI regarding the use of acupuncture in treating obstetric and gynecological diseases,we aimed to summarize the proven evidence of using acupuncture in maintaining women’s health by considering both its effectiveness and the underlying mechanisms behind its effects.

关键词： acupuncture women health clinical efficacy mechanism

Improving tree health assessment accuracy at low temperatures:considering the effect of trunk ice content on electrical resistance and stress wave tomography

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Journal of Forestry Research 2023年第5期34卷 1503-1510页

作者： jiaxing Guo Peng Wang Yuting Wang Huadong Xu College of Engineering and Technology Northeast Forestry UniversityHarbin 150040People’s Republic of China Forest Science Research Institute of Tibet Municipality Lhasa 850000People’s Republic of China

Accurate decay detection and health assessment of trees at low temperatures is an important issue for forest management and ecology in cold *** temperature ice formation on tree health assessment is *** electric resistance tomography and stress wave tomography are two widely used methods for the detection of tree decay,this study investigated the effect of ice content on trunk electrical resistance and stress wave velocity to improve tree health assessment *** content,trunk electrical resistance and stress wave velocity using time domain reflectometry were carried out on Larix gmelinii and Populus *** content is based on moisture content *** ice content of both species showed a trend of increasing and then *** was opposite with ambient *** the decrease of temperatures,daily average ice content increased,but the range narrowed gradually and both electrical resistance and stress wave velocity *** increased rapidly near 0℃,mainly caused by ice formation(phase change and freezing of free water)in live *** addition,both are positively correlated with ice *** results suggest that ice content should be considered for improving the accuracy of tree decay detection and health evaluation using electric resistance tomography and stress wave velocity methods under low temperatures.

关键词： Cross-section electrical resistance Cross-section stress wave velocity Ambient temperatures Ice content Wood decay detection Tree heath