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Synthesis of High Molecular Weight Polyethylene and E-MA Copolymers Using Iminopyridine Ni(Ⅱ) and Pd(Ⅱ) Complexes Containing a Flexible Backbone and Rigid Axial Substituents

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Chinese Journal of Polymer Science 2023年第2期41卷 233-239页

作者： Yu-Dan Liao Qi Cai sheng-Yu dai School of Chemical and Environmental Engineering Anhui Polytechnic UniversityWuhu241000China Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei230601China

Suppressing the chain transfer reactions during polymerization in late-transition metal-catalyzed olefin polymerization systems is the key to obtaining high molecular weight polyolefin materials. In this work, two efficient strategies(“sandwich” and rotation-restricted strategies)to retard chain transfer reactions in ethylene(co)polymerization were employed for the iminopyridyl system. Herein, a family of iminopyridyl Ni(Ⅱ)and Pd(Ⅱ) complexes with a flexible backbone and rigid axial bulky aryl substituents were designed, synthesized and characterized. In ethylene polymerization, the iminopyridyl Ni(Ⅱ) and Pd(Ⅱ) catalysts using the two strategies exhibited reasonable activities and generated highly branched polyethylenes with high molecular weights, where catalysts with dibenzosuberyl substituents exhibited significantly higher activities and produced higher molecular weight polyethylene than catalysts with 8-arylnaphthalenyl substituent. A similar trend of activities and molecular weights was also found in the copolymerization of ethylene with MA using the Pd(Ⅱ) catalysts. Moreover, highly branched E-MA copolymers with moderate to high molecular weights and high incorporation ratios(up to 17.4 mol%) were generated with the two Pd(Ⅱ) catalysts. Most interestingly, as compared with the dibenzhydryl Ni(Ⅱ) and Pd(Ⅱ) catalysts, the catalysts using the two strategies exhibited a superior ability to retard the chain transfer reactions and generated polymers and copolymers with 1-2 orders of magnitude higher molecular weights during ethylene(co)polymerization.

关键词： Ni(Ⅱ)and Pd(Ⅱ) Suppressing chain transfer High molecular weight Ethylene(co)polymerization

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Advanced Transmission Electron Microscopy for Identification of Atomic-Scale Configurations of Zeolite-Supported Metal Catalysts

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Chinese Journal of Chemistry 2022年第19期40卷 2371-2373页

作者： Xuan Tang Jiajie Ye Yun Guo sheng dai Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Frontiers Science Center for Materiobiology and Dynamic ChemistryEast China University of Science and TechnologyShanghai200237 China Key Laboratory for Advanced Materials Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and Technology130 Meilong RoadShanghai200237 China

Zeolite-supported metal catalysts have important applications in various catalytic reactions,but unveiling their atomic-scale structures is always a grand *** developed transmission electron microscopy(TEM)characterization techniques,e.g.,integrated differential-phase contrast(iDPC)scanning transmission electron microscopy(STEM)is emerging as a powerful tool for visualizing the electron beam-sensitive materials at atomic resolution,thus,providing new opportunities for imaging the exact configurations of metal species in the various channels of *** emerging topic summarizes recent progress utilizing iDPC-STEM-related technique for determination of the structures of metal species in zeolites that should offer insights into the structure-property relationships of zeolite-supported metal catalysts.A brief perspective about the new TEM technique is also presented,showing prospects in this field that will stimulate further scientific research in zeolite-supported metal catalysts.

关键词： Metal-zeolite Catalyst structure Heterogeneous catalysis TEM characterization Electron microscopy

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A critical review of ferritin as a drug nanocarrier:Structure,properties,comparative advantages and challenges

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Particuology 2022年第5期20卷 65-84页

作者： Shuang Yin Kenneth Davey sheng dai Yongdong Liu Jingxiu Bi School of Chemical Engineering&Advanced Materials Faculty of EngineeringComputer and Mathematical Sciences.University of AdelaideAdelaideAustralia Department of Chemical Engineering Brunei University LondonUxbridge UB83PHUnited Kingdom State Key Laboratory of Biochemistry Engineering.Institute of Process Engineering Chinese Academy of Sciences.BeijingChina

Ferritin stores and releases iron ions in *** is globally important as a drug *** is because of its unique hollow-spherical structure,desirable stability and biological *** drug-loading approaches plus various functionalization approaches have been developed to improve ferritin in response to differing demands in disease ***,we critically review ferritin drug delivery and evaluate its diverse drug-loading and functionalization approaches,we:(1)Introduce basic structural and property information related to ferritin as a drug nanocarrier;(2)Contrast in detail the different means to load drugs and the selection of drug loading means;(3)Discuss multiple ferritin functionalization approaches,together with related advantages and potential risks;and,(4)Compare ferritin with alternative,commonly-used drug *** conclude that despite that no drugs based on ferritin are commercially available,the market potential for it is significant,and evaluate future research *** from this work will be of immediate benefit and interest to a wide range of researchers and manufacturers for drug delivery using ferritin.

关键词： Ferritin Drug delivery Drug nanocarrier Protein functionalization

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Steering structural mesoporosity and working microenvironment of Fe-N-C catalysts for boosting cathodic mass transport of zinc-air batteries

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Science China Chemistry 2022年第8期65卷 1670-1678页

作者： Hang Shen Yanyan Jia Yanbin Qi sheng dai Hongliang Jiang Yihua Zhu Chunzhong Li Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Key Laboratory for Ultrafine Materials of Ministry of Education School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Institute of Fine ChemicalsSchool of Chemistry&Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Transition metal-N-C materials have considerably been demonstrated as promising catalysts for cathodic oxygen reduction reaction(ORR)in Zn-air *** efforts mainly focus on tailoring coordination structure and identifying active sites of metal-N-C materials for ORR,while the mass transport of metal-N-C employed in catalytic layers of working electrodes is seldom ***,a Fe-N-C single-atom catalyst featuring high mesoporosity and abundant electrochemically accessible active sites is developed through post-loading Fe species into defective N-doped carbon *** Fe-N-C single-atom catalyst serving as the air cathode of Zn-air battery delivers a peak power density of 189.9 mW cm^(−2),significantly larger than 114.2 mW cm^(−2) of commercial Pt/C and 162.9 mW cm^(−2) of the Fe-N-C contrast catalyst with low *** importantly,through adding hydrophobic polytetrafluoroethylene(PTFE)nanoparticles in the catalytic layer of air cathode,the peak power density of Fe-N-C single-atom catalyst is further increased to 212.3 mW cm^(−2).The increased peak power density is attributed to the enhancement of O_(2) mass transport,as evidenced by a substantially decreased diffusion layer thickness that is obtained from electrochemical impedance spectroscopy.

关键词： electrocatalysis oxygen reduction reaction single-atom catalyst mass transport Zn-air batteries

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退火温度对多向锻造Ti-6Al-4V合金显微组织演变和拉伸行为的影响

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Transactions of Nonferrous Metals Society of China 2024年第6期34卷 1864-1877页

作者：刘石双蔡建明周毅曹京霞张旺峰戴圣龙黄旭曹春晓中国航发北京航空材料研究院先进钛合金重点实验室北京100095

为调节Ti−6Al−4V锻件显微组织和力学性能,进行一系列退火处理。结果表明:锻态和退火态组织均呈现由等轴初生α相(αp)和转变β相(βt)组成的双态组织。随着退火温度的升高,次生α相(αs)从β相中析出。组织中没有明显的织构,晶体取向均... 详细信息

为调节Ti−6Al−4V锻件显微组织和力学性能,进行一系列退火处理。结果表明:锻态和退火态组织均呈现由等轴初生α相(αp)和转变β相(βt)组成的双态组织。随着退火温度的升高,次生α相(αs)从β相中析出。组织中没有明显的织构,晶体取向均匀分布。同时,强度呈先增大后减小的变化趋势,而塑性没有明显的变化。在860℃退火处理时,由于析出的细小αs相含量较高,合金具有强度和塑性的良好匹配。所有断口表面均包含大量韧窝,为典型的韧性断裂特征。在断口附近发现微裂纹、微孔洞和扭结αp/αl相(等轴αp相和片层α相)特征。

关键词： Ti−6Al−4V锻件退火温度显微组织演变次生α相拉伸性能韧性断裂

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Ultrasound-driven fabrication of high-entropy alloy nanocatalysts promoted by alcoholic ionic liquids

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Nano Research 2022年第6期15卷 4792-4798页

作者： Francis Okejiri Zhenzhen Yang Hao Chen Chi-Linh Do-Thanh Tao Wang Shize Yang sheng dai Department of Chemistry The University of TennesseeKnoxvilleTN 37996USA Chemical Sciences Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Center for Functional Nanomaterials Brookhaven National LaboratoryUptonNew York 11973USA Eyring Materials Center Arizona State UniversityTempeAZ 85287USA

High-entropy alloy nanoparticles(HEA-NPs)are highly underutilized in heterogeneous catalysis due to the absence of a reliable,sustainable,and facile synthetic ***,we report a facile synthesis of HEA nanocatalysts realized via an ultrasounddriven wet chemistry method promoted by alcoholic ionic liquids(AILs).Owing to the intrinsic reducing ability of the hydroxyl group,AILs were synthesized and utilized as environmentally friendly alternatives to conventional reducing agents and volatile organic solvents in the synthetic *** high-intensity ultrasound irradiation,Au^(3+),Pd^(2+),Pt^(2+),Rh^(3+),and Ru^(3+)ions were coreduced and transformed into single-phase HEA(AuPdPtRhRu)nanocrystals without *** results reveal that the as-synthesized nanocrystals are composed of elements of Au,Pd,Pt,Rh,and Ru as *** to the monometallic counterparts such as Pd-NPs,the carbon-supported HEA nanocatalysts show superior catalytic performance for selective hydrogenation of phenol to cyclohexanone in terms of yield and *** synthetic strategy provides an improved and facile methodology for the sustainable synthesis of multicomponent alloys for catalysis and other applications.

关键词： high-entropy alloy alcoholic ionic liquid sustainability ultrasonication nanoparticles hydrogenation

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Hydrophobic 1-octadecanethiol functionalized copper catalyst promotes robust high-current CO_(2) gas-diffusion electrolysis

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Nano Research 2022年第2期15卷 1393-1398页

作者： Liangyao Xue Xuefeng Wu Yuanwei Liu Beibei Xu Xuelu Wang sheng dai Pengfei Liu Huagui Yang Key Laboratory for Ultrafine Materials of Ministry of Education Shanghai Engineering Research Center of Hierarchical NanomaterialsSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Physics Department and Shanghai Key Laboratory of Magnetic Resonance School of Physics and Materials ScienceEast China Normal UniversityShanghai 200062China Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Institute of Fine ChemicalsSchool oj Chemistry and Molecular EngineeringEast China University of Science and Technology130 Meilong RoadShanghai 200237China

The electrocatalytic reduction of CO_(2) presents a promising strategy in addressing environmental and energy *** progress has been achieved via CO_(2) gas diffusion electrolysis,to react at high selectivity and high ***,the gas diffusion layer(GDL)of the gas diffusion electrode(GDE)still suffers from low tolerance and limited active ***,the hydrophobic 1-octadecanethiol molecular was functionalized over the Cu catalyst layer of the GDE,which simultaneously stabilizes the GDL and exposes abundant active solid-liquid-gas three-phase *** resultant GDE exhibits multi-carbon(C_(2+))product selectivity over faradaic efficiency(FE)of 70.0%in the range of 100 to 800 mA·cm^(-2),with the peak FE^(c2+)of 85.2%at 800 mA·cm^(-2).Notably,the strengthened GDE could continuously drive high-current electrolysis for more than 100 h without *** work opens a new way to improve CO_(2) gas diffusion electrolysis via surface molecular engineering.

关键词： CO_(2)reduction reaction gas diffusion electrolysis multi-carbon products molecular engineering hydrophobicity

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基于“辨色论质”的新疆紫草质量评价研究

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药物分析杂志 2024年第5期44卷 766-771页

作者：连超杰戴胜云刘杰过立农乔菲杨锐王会娟郑健刘杰中国食品药品检定研究院北京102629 伊犁哈萨克自治州检验检测认证研究院伊型835000

目的:测量紫草的色泽,测定紫草中6个主要紫色素类成分(乙酰紫草素、β-乙酰氧基异戊酰阿卡宁、去氧紫草素、异丁酰紫草素、β,β’-二甲基丙烯酰阿卡宁、异戊酰紫草素)的含量,研究新疆紫草色泽与6个主要紫色素成分含量的相关性。方法:... 详细信息

目的:测量紫草的色泽,测定紫草中6个主要紫色素类成分(乙酰紫草素、β-乙酰氧基异戊酰阿卡宁、去氧紫草素、异丁酰紫草素、β,β’-二甲基丙烯酰阿卡宁、异戊酰紫草素)的含量,研究新疆紫草色泽与6个主要紫色素成分含量的相关性。方法:采用分光测色仪测定样品粉末的L、a、b值用于表征紫草的色泽。国际照明委员会(CIE)制定了Lab颜色模型,是人类视觉的数字化描述,L值越大表示亮度越大,a值增大表示偏红减小表示偏绿,b值增大表示偏黄减小表示偏蓝;采用高效液相色谱法(HPLC)测定紫色素类成分的含量,使用SPSS软件计算L、a、b值与6个主要紫色素含量的相关程度。结果:135批样品乙酰紫草素的含量为0.01%~3.39%,β-乙酰氧基异戊酰阿卡宁含量为0.00%~1.95%,去氧紫草素含量为0.00%~0.23%,异丁酰紫草素含量为0.01%~1.13%,异戊酰紫草素含量为0.02%~2.88%,β,β’-二甲基丙烯酰阿卡宁含量为0.01%~2.17%。紫草药材的L(黑_白)色度值与乙酰紫草素、β-乙酰氧基异戊酰阿卡宁和异丁酰紫草素3个成分的含量呈显著负相关关系,斯皮尔曼相关系数在-0.138和-0.222之间;a(绿_红)色度值与β-乙酰氧基异戊酰阿卡宁、去氧紫草素、异丁酰紫草素、β,β’-二甲基丙烯酰阿卡宁、异戊酰阿卡宁的含量均呈现显著的正相关,斯皮尔曼相关系数在0.176和0.355之间;b(蓝-黄)色度值与乙酰紫草素、去氧紫草素、异丁酰紫草素、β,β’-二甲基丙烯酰阿卡宁、异戊酰阿卡宁均呈现显著的相关性,其中,与β,β’-二甲基丙烯酰阿卡宁呈正相关,系数为0.290,与其余4个成分呈负相关,系数在-0.325和-0.633之间。结论:建议紫草(新疆紫草)的含量测定项修订为β,β’-二甲基丙烯酰阿卡宁不得少于0.30%并且异丁酰紫草素不得少于0.29%。

关键词：紫草色泽乙酰紫草素 β-乙酰氧基异戊酰阿卡宁去氧紫草素异丁酰紫草素 β,β’-二甲基丙烯酰阿卡宁异戊酰紫草素相关性分析

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基于巢式PCR的紫草鉴别引物筛选

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药物分析杂志 2024年第5期44卷 756-765页

作者：刘杰谷海媛戴胜云乔菲连超杰郑健加沙尔·斯哈克中国食品药品检定研究院北京102629 沈阳药科大学沈阳110016 伊犁哈萨克自治州检验检测认证研究院伊型835000

目的:基于巢式聚合酶链式反应(PCR)理念设计并筛选出可用于高效扩增与鉴别紫草市场样品真伪的特异性引物。方法:针对新疆紫草的ITS序列和紫草非《中华人民共和国药典》品ITS2序列,利用Primer Premier 5软件进行巢式引物设计;比较ITS2通... 详细信息

目的:基于巢式聚合酶链式反应(PCR)理念设计并筛选出可用于高效扩增与鉴别紫草市场样品真伪的特异性引物。方法:针对新疆紫草的ITS序列和紫草非《中华人民共和国药典》品ITS2序列,利用Primer Premier 5软件进行巢式引物设计;比较ITS2通用引物PCR和巢式PCR对紫草药材基因组DNA的扩增效率;基于巢式引物直接扩增紫草基因组DNA,并进行琼脂糖凝胶电泳检测;基于扩增产物片段长度、变异位点覆盖情况对设计的紫草药材特异性引物进行评价。结果:经过Primer Premier 5软件进行引物设计共选出11对引物进行合成;巢式PCR对紫草药材基因组DNA的扩增效率明显优于ITS2通用引物PCR;基于巢式引物直接扩增紫草基因组DNA琼脂糖凝胶电泳检测的结果明显优于ITS2引物直接扩增紫草基因组DNA,且呈单一条带;确定AE-9S/AE-2A、AE-4S/AE-10A、AE-12S/10A、AE-29S/AE-29A共4对引物适用于紫草正伪品鉴定。结论:在DNA条形码鉴定和巢式PCR技术的基础上,确定了4对可以用于有效区分药材市场中主流的新疆紫草和紫草非《中华人民共和国药典》品的特异性引物,为后续紫草药材及其他中药民族药品种的鉴定方法研究与开发提供了可参考的依据。

关键词：紫草聚合酶链式反应(PCR) 内部转录间隔区2(ITS2) DNA条形码巢式PCR(nPCR)

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Development of an integrated dynamic model for supply security and resilience analysis of natural gas pipeline network systems

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Petroleum Science 2022年第2期19卷 761-773页

作者： Huai Su Enrico Zio Zong-Jie Zhang Chang-Zheng Xiong Qian-sheng dai Qing-Wei Wu Jin-Jun Zhang National Engineering Laboratory for Pipeline Safety/MOE Key Laboratory of Petroleum Engineering/Beijing Key Laboratory of Urban Oil and Gas Distribution Technology China University of Petroleum-Beijing102249BeijingChina Dipartimento di Energia Politecnico di MilanoVia La Masa 3420156MilanoItaly MINES ParisTech PSL Research UniversityCRCSophiaAntipolisFrance PipeChina West East Gas Pipeline Company Dongfushan Road 458Pudong District200122ShanghaiChina China Special Equipment Inspection and Research Institute Heping Street 2Chaoyang District100013BeijingChina

An integrated dynamic model of natural gas pipeline networks is developed in this *** for gas supply,e.g.,pipelines,junctions,compressor stations,LNG terminals,regulation stations and gas storage facilities are included in the *** components are firstly modeled with respect to their properties and functions and,then,integrated at the system level by Graph *** model can be used for simulating the system response in different scenarios of operation,and evaluate the consequences from the perspectives of supply security and resilience.A case study is considered to evaluate the accuracy of the model by benchmarking its results against those from literature and the software Pipeline ***,the model is applied on a relatively complex natural gas pipeline network and the results are analyzed in detail from the supply security and resilience points of *** main contributions of the paper are:firstly,a novel model of a complex gas pipeline network is proposed as a dynamic state-space model at system level;a method,based on the dynamic model,is proposed to analyze the security and resilience of supply from a system perspective.

关键词： Natural gas pipeline networks Dynamic modeling State space model Graph theory Resilience of natural gas supply

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