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Highly stable side-chain-type cardo poly(aryl ether ketone)s membranes for vanadium flow battery

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Chinese Chemical Letters 2024年第3期35卷 167-170页

作者： Ziming zhao Qing Dai Sihan Huang Wenjing Lu Yaohan Chen Jifu Zheng Suobo Zhang Shenghai Li xianfeng Li Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Division of Energy Storage Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Vanadium flow batteries(VFBs)have drawn considerable attention as an emerging technology for largescale energy storage systems(ESSs).One of the pivotal challenges is the availability of eligible ion exchange membranes(ICMs)that provide high ion selectivity,proton conductivity,and stability under rigorous condition.Herein,a‘side-chain-type’strategy has been employed to fabricate highly stable phenolphthalein-based cardo poly(arylene ether ketone)s(PAEKs)membrane with low area resistance(0.058Ωcm^(2)),in which flexible alkyl spacers effectively alleviated inductive withdrawing effect from terminal ion exchange groups thus enabling a stable backbone.The assembled VFBs based on PAEKs bearing pendent alkyl chain terminated with quaternary ammonium(Q-PPhEK)demonstrated an energy efficiency above 80%over 700 cycles at 160 mA/cm^(2).Such a remarkable results revealed that the side-chain-type strategy contributed to enhancing the ICMs stability in strong oxidizing environment,meanwhile,more interesting backbones would be woken with this design engaging in stable ICMs for VFBs.

关键词： Vanadium flow battery Energy storage technology Ion exchange membrane Ion transport mechanism Poly(arylene ether ketone)s(PAEKs)

A multi-parameter-induced activation of gas therapeutic platform to remarkably amplify photodynamic therapy efficacy

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Science China Chemistry 2024年第7期67卷 2403-2411页

作者： Jie Sun Ziwen Zhang Hongyu Wu Xuemei Dong Chengjun Dong Lixin Sun Zhiqian Guo Yingchao Liu xianfeng Gu Chunchang zhao Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Institute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China Department of Medicinal Chemistry School of PharmacyFudan UniversityShanghai 201203China Shandong Provincial Hospital Affiliated to Shandong First Medical University Shandong First Medical University&Shandong Academy of Medical ScienceJinan 250021China

Gas therapy(GT)combined with photodynamic therapy(PDT)is an effective strategy to compensate for the PDT limitation caused by the hypoxic tumor microenvironment,which can greatly improve PDT efficacy.The uncontrolled leakage of gas molecules during delivery seriously hinders its practical biological application.Herein,we report a multifunction nanomedicine that enables precise gas therapy(including carbon monoxide(CO)release and H_(2)S depletion)using a multi-parameter-induced activation gas release strategy,enlarging the PDT efficacy.This nanomedicine uses a disulfide bond to covalently link a photosensitizer with the CO donor 3-hydroxyflavone(3-HF).The disulfide bond can be specifically consumed in H_(2)S-rich tumor areas,releasing the CO donor(3-HF),and also depleting H_(2)S.More importantly,the photo-controlled production of^(1)O_(2)can induce 3-HF precise release of CO in the tumor location.Such H_(2)S,light,and^(1)O_(2)multi-parameter-induced activation of gas release strategy ensures the accuracy of GT to amplify PDT efficiency.As expected,in vitro and in vivo investigations show that GT makes up for the PDT limitation,exhibiting the highest tumor therapeutic effect.This multi-parameter-activated design strategy provides a new way to improve the precision and efficacy of multimodal synergistic therapy of tumors.

关键词： gas therapy precision gas release hydrogen sulfide depletion photodynamic therapy multimodal synergistic therapy

Positivity of Fock Toeplitz Operators via the Berezin Transform

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Chinese Annals of Mathematics,Series B 2016年第4期37卷 533-542页

作者： xianfeng zhao Shanghai Center for Mathematical Sciences Fudan University

This paper deals with the relationship between the positivity of the Fock Toeplitz operators and their Berezin transforms. The author considers the special case of the bounded radial function φ(z) = a + be^(-α|z|^2)+ ce^(-β|z|^2), where a, b, c are real numbers and α, β are positive numbers. For this type of φ, one can choose these parameters such that the Berezin transform of φ is a nonnegative function on the complex plane, but the corresponding Toeplitz operator Tφ is not positive on the Fock space.

关键词：极性变换 Toeplitz算子 k算子 Berezin变换 Fock空间有界函数非负函数复平面

Invertibility of Bergman Toeplitz operators with harmonic polynomial symbols

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Science China Mathematics 2020年第5期63卷 965-978页

作者： Nanxing Guan xianfeng zhao School of Mathematics and Statistics Chuxiong Normal UniversityChuxiong 675000China College of Mathematics and Statistics Chongqing UniversityChongqing 401331China

Let p be an analytic polynomial on the unit disk.We obtain a necessary and sufficient condition for Toeplitz operators with the symbol z+p to be invertible on the Bergman space when all coefficients of p are real numbers.Furthermore,we establish several necessary and sufficient,easy-to-check conditions for Toeplitz operators with the symbol z+p to be invertible on the Bergman space when some coefficients of p are complex numbers.

关键词： Bergman space Toeplitz operator harmonic polynomial symbol invertibility

Novel cover selection criterion for spatial steganography using linear pixel prediction error

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Science China(Information Sciences) 2016年第5期59卷 245-247页

作者： Wei HUANG xianfeng zhao Software School Xiamen University State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of Sciences

Dear editor,In recent years,steganography and steganalysis[1]of empirical covers have been developing rapidly.Empirical cover,such as image and other multimedia,is one of the most commonly used content in daily life,however,the model of images is still unknown.Therefore,the combat against image steganography and steganalysis would be challenging yet beneficial.

关键词： Novel cover selection criterion for spatial steganography using linear pixel prediction error Figure

Roadmap for rechargeable batteries:present and beyond

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Science China Chemistry 2024年第1期67卷 13-42页

作者： Sen Xin Xu Zhang Lin Wang Haijun Yu Xin Chang Yu-Ming zhao Qinghai Meng Pan Xu Chen-Zi zhao Jiahang Chen Huichao Lu Xirui Kong Jiulin Wang Kai Chen Gang Huang Xinbo Zhang Yu Su Yao Xiao Shu-Lei Chou Shilin Zhang Zaiping Guo Aobing Du Guanglei Cui Gaojing Yang Qing zhao Liubing Dong Dong Zhou Feiyu Kang Hu Hong Chunyi Zhi Zhizhang Yuan xianfeng Li Yifei Mo Yizhou Zhu Dongfang Yu Xincheng Lei Jianxiong zhao Jiayi Wang Dong Su Yu-Guo Guo Qiang Zhang Jun Chen Li-Jun Wan CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China University of Chinese Academy of Sciences.Beijing 100049 China Institute of Advanced Battery Materials and Devices Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China Key Laboratory of Advanced Functional Materials Ministry of EducationBeijing University of TechnologyBeijing 100124China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China State Key Laboratory of Chemistry and Utilization of Carbon-Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830046China Department of Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChangchun 130022China Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaide 5000Australia Qingdao Industrial Energy Storage Research Institute Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101China Frontiers Science Center for New Organic Matter Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education)College of ChemistryNankai UniversityTianjin 300071China College of Chemistry and Materials Science Jinan UniversityGuangzhou 511443China Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China Department of Materials Science and Engineering City University of Hong KongHong Kong 999077China Division of Energy Storage Dalian National Laboratory for Clean Energy(DNL)Dalian Institute of Chem

Rechargeable batteries currently hold the largest share of the electrochemical energy storage market,and they play a major role in the sustainable energy transition and industrial decarbonization to respond to global climate change.Due to the increased popularity of consumer electronics and electric vehicles,lithium-ion batteries have quickly become the most successful rechargeable batteries in the past three decades,yet growing demands in diversified application scenarios call for new types of rechargeable batteries.Tremendous efforts are made to developing the next-generation post-Li-ion rechargeable batteries,which include,but are not limited to solid-state batteries,lithium–sulfur batteries,sodium-/potassium-ion batteries,organic batteries,magnesium-/zinc-ion batteries,aqueous batteries and flow batteries.Despite the great achievements,challenges persist in precise understandings about the electrochemical reaction and charge transfer process,and optimal design of key materials and interfaces in a battery.This roadmap tends to provide an overview about the current research progress,key challenges and future prospects of various types of rechargeable batteries.New computational methods for materials development,and characterization techniques will also be discussed as they play an important role in battery research.

关键词： energy storage rechargeable batteries battery materials electrochemistry

河北省国家备案众创空间运行效率的评价分析——基于DEA三阶段模型

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经济研究导刊 2024年第3期 31-33页

作者：赵现锋河北地质大学管理学院石家庄050031

随着科技创新活动的不断发展以及高技术产业规模的不断扩大,科技企业孵化器在科技企业孵化、科研成果转化等方面发挥了巨大作用。但同时运行和配置效率较低,区域科技企业孵化器发展不均衡等问题也制约着河北省科技企业孵化器的服务功能... 详细信息

随着科技创新活动的不断发展以及高技术产业规模的不断扩大,科技企业孵化器在科技企业孵化、科研成果转化等方面发挥了巨大作用。但同时运行和配置效率较低,区域科技企业孵化器发展不均衡等问题也制约着河北省科技企业孵化器的服务功能(黄虹等,2013)。基于此,通过DEA三阶段模型对河北省86家国家备案众创空间的运行效率进行评价和分析,以期为河北省众创空间未来发展和政策制定提供参考。

关键词： DEA 河北省国家备案众创空间运行效率

增强组合差分乘积形态学滤波的轴承故障特征提取方法

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重庆大学学报 2024年第3期47卷 96-106页

作者：徐先峰赵卫峰邹浩泉宋亚囡长安大学电子与控制工程学院西安710064

针对滚动轴承故障信号的非线性、非平稳、强噪声特性导致的常规时频域特征提取方法受限问题,提出一种增强组合差分乘积形态学滤波的轴承故障特征提取方法。在分析数学形态学4种基本运算的正、负冲击脉冲提取特性的基础上,运用级联、差... 详细信息

针对滚动轴承故障信号的非线性、非平稳、强噪声特性导致的常规时频域特征提取方法受限问题,提出一种增强组合差分乘积形态学滤波的轴承故障特征提取方法。在分析数学形态学4种基本运算的正、负冲击脉冲提取特性的基础上,运用级联、差分、乘积构造的一种新的组合差分乘积算子(combination difference multiply operator,CDMO)具备了同时提取正、负冲击脉冲的能力,并发挥梯度乘积运算对脉冲提取更敏感的优势,实现故障信息的充分提取。引入故障特征频率比指标优化CDMO结构元素参数,修正待处理信号的几何特征,提取与结构元素相匹配的信号特征信息。在CDMO滤波的基础上,借助三阶累积量切片谱技术能够抑制高斯噪声、突出二次耦合分量的优势,准确提取故障特征频率及其倍频,增强轴承故障特征提取能力并抑制噪声干扰。依托2种不同来源的工程实际信号并与经典故障特征提取方法对比分析,验证了所提方法的有效性。

关键词：滚动轴承形态学滤波三阶累积量切片谱特征提取

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复合菌群构建及其石油烃降解特性

化学工程 2024年第2期52卷 17-22页

作者：刘杰孙先锋赵敏吴蔓莉韩宇星西安工程大学环境与化学工程学院陕西西安710048 中国石油长庆油田分公司油气工艺研究院陕西西安710016 西安建筑科技大学环境与市政工程学院陕西西安710055

为获得高效降解石油烃复合菌群,对实验室保存的菌株进行石油烃降解效果及原油4组分降解能力分析研究,筛选出了4株菌(A1、A3、Y3、Y4),对其进行ITS和16S rRNA分子鉴定,确认4株菌的分类信息,并优化高效降解菌株的复配方式。结果显示:A1属... 详细信息

为获得高效降解石油烃复合菌群,对实验室保存的菌株进行石油烃降解效果及原油4组分降解能力分析研究,筛选出了4株菌(A1、A3、Y3、Y4),对其进行ITS和16S rRNA分子鉴定,确认4株菌的分类信息,并优化高效降解菌株的复配方式。结果显示:A1属于不动杆菌属(Acinetobacter)、A3属于芽胞杆菌属(Bacillus)、Y3和Y4均为假丝酵母菌属(Candida);A1、A3、Y3、Y4对石油烃的降解率分别为42.27%、40.95%、62.02%、69.84%;其中Y4对烷烃和芳烃降解效果最佳,降解率分别为65.71%和23.69%,沥青质降解效果最好的是A1,胶质降解效果最好的是Y3,降解率分别为22.74%和21.22%,A3对各组分降解能力均衡;A1、A3、Y4复合的菌群降解效果最佳,其降解率高达83.11%,相较于单一菌株提高了1.19—2.03倍;A1、A3、Y4的最佳接种量比例为0.9∶0.9∶1.5,其降解率可达88.34%。该研究成功筛选出一种新的高效降解石油烃的菌群,对进一步研究和应用于石油污染治理具有重要指导意义。

关键词：菌株筛选复合菌群石油污染石油烃降解响应面