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Phenols/Al(C_(6)F_(5))_(3) Initiation Systems for Cationic Polymerizations of Isobutylene

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Chinese Journal of Polymer Science 2023年第5期41卷 713-719,I0008页

作者： Ling Cai qi-yuan wang Xin-Li Liu Dong-Mei Cui State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Polymer Science and Engineering University of Science and Technology of ChinaHefei 230026China

We report herein the cationic polymerization of isobutylene(IB)under mild conditions is realized with a new binary initiation system generated by simply mixing a Lewis super acid Al(C_(6)F_(5))_(3) and a substituted phenol(RPhOH).Polymers with medium and/or high molecular weights(M_(W)=4.9×10^(4)-27.7×10^(4) g·mol^(-1))can be obtained in toluene and temperatures from-20℃to 0℃.NMR spectrum analysis and DFT sim ulation reveals the in situ generated acidic coordinating complex Ak(C_(6)F_(5))_(3)·RPhOH is the initiating active species,which fu rther tran sformed into the ion-pair[Al(C_(6)F_(5))_(3)ORPh]^(-)[PIB]^(+)of the active intermediates upon growing IB monomers where the counter anion[Al(C_(6)F_(5))_(3)R^(O)Ph]-coordinates to the macrocation via the phenoxy *** catalyst performances are the concert effects of the steric bulkiness and electronics of the counter anion on the coordinating strength to the macrocation,which is significant to the stability of the active species.

关键词： Cationic polymerization Phenols Lewis super acid Polyisobutylene

Dynamic Ring-chain Equilibrium of Nucleophilic Thiol-yne "Click" Polyaddition for Recyclable Poly(dithioacetal)s

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Chinese Journal of Polymer Science 2021年第9期39卷 1146-1154页

作者： Jin-Xia Lei qi-yuan wang Fu-Sheng Du Zi-Chen Li Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of Polym.Chem.&Physics of Ministry of EducationDepartment of Polymer Science&EngineeringCollege of Chemistry and Molecular EngineeringCenter for Soft Matter Science and EngineeringPeking UniversityBeijing 100871China

We report a dynamic polymerization system based on the reversible nucleophilic Michael polyaddition of activated alkynes and *** poly(dithioacetal)s(P1-P4)were prepared via the base-catalyzed thiol-yne"click"polyaddition of two dithiols(1,4-butanedithiol(4S)and 1,5-pentanedithiol(5S))and two alkynones(3-butyn-2-one(Y1)and 1-phenyl-2-propyn-1-one(Y2))at high *** systematically investigated the base-catalyzed polymerization of 4S and Y1(for polymer PI)under different conditions,and found that this polymerization was a highly concentration-dependent dynamic system:polymer PI was formed at high concentration,while seven-membered dithioacetal,1-(1,3-dithiepan-2-yl)propan-2-one(C1),was obtained at low *** polymerization of 4S and Y2(for polymer P4)displayed similar polymerization behavior,generating 2-(1,3-dithiepan-2-yl)-1-phenylethanone(C4)at low *** the contrary,polymer P2(from Y1 and 5S)was exclusively obtained with no formation of eight-membered *** polymerizations of Y1 with 1,2-ethanedithiol(2S)and 1,3-dimercaptopropane(3S)only afforded corresponding five-and six-membered dithioacetals,1-(1,3-dithiolan-2-yl)propan-2-one(C2)and 1-(1,3-dithian-2-yl)propan-2-one(C3).This dynamic behavior of PI and P4 was attributed to the concentration-dependent retro-Michael addition reaction between a thiol and a β-sulfido-α,β-unsaturated carbonyl compound catalyzed by ***,polymers P1 and P4 could be depolymerized into Cl and C4 in yields of 58% and 95%,*** ring-opening polymerization of Cl at high concentration could successfully regenerate polymer ***,a new type of closed-loop recyclable poly(dithioacetal)s was developed.

关键词： Poly(dithioacetal)s Nucleophilic thiol-yne"click"polyaddition Chemical recycling Ring-chain equilibrium

Electrolyte-gated SrCoO_(x) FET sensor for highly sensitive detecting pH in extreme alkalinity solution

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Nano Research 2024年第4期17卷 3079-3086页

作者： Han Zhou Gaocan qi Wenbin Li Yuhang wang Zhihao yuan School of Materials Science and Engineering Tianjin Key Lab of Photoelectric Materials&Devicesand Key Laboratory of Display Materials and Photoelectric Devices(Ministry of Education)Tianjin University of TechnologyTianjin 300384China

The pH monitoring is significantly important in chemical industry,biological process,and pollution ***,it remains a great challenge to measure pH in extreme alkalinity ***,we employ an electrolyte-gated field-effect-transistor(FET)strategy using non-stoichiometric SrCoO_(x) with rich oxygen-vacancy defects as channel materials for detecting extreme *** corresponding channel can provide effective oxygen-ion-migration sites for reversible transformation of OH-↔O_(2)-+H^(+)driven by electric *** resultant electrolyte-gated FET sensor exhibits a sensitive linear response to high concentrations of alkaline solution,1–20 ***,the sensor has the ability to directly indicate the pH values ranging from 14.0 to 17.0 in consideration of ion-activity coefficient *** work offers a great possibility for directly detecting base concentration as well as pH values in extreme alkaline solutions.

关键词： field-effect-transistor(FET) pH sensor extreme alkaline solution SrCoO_(x) oxygen-ion migration

Characterization of a smog chamber for studying formation of gas-phase products and secondary organic aerosol

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Journal of Environmental Sciences 2024年第2期136卷 570-582页

作者： qi yuan Zhuozhi Zhang Meng wang Kin Fai Ho Tao wang Shuncheng Lee Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina School of Public Health and Primary Care The Chinese University of Hong KongShatinHong KongChina

Smog chambers provide a potent approach to explore the secondary organic aerosol formation under varied *** study describes the construction and characterization of a new smog chamber facility for studying the formation mechanisms of gas-phase products and secondary organic aerosol from the photooxidation of volatile organic *** chamber is a 5.4 m^(3) Fluorinated Ethylene Propylene(FEP)Teflon reactor with the potential to perform photooxidation experiments at controlled temperature and relative *** characterizations were conducted for evaluation of stability of environmental parameters,mixing time,background contamination,light intensity,and wall losses of gases and *** photolysis rate of NO_(2)(J_(NO2))ranged from(1.02-3.32)×10^(-3)sec^(-1),comparable to the average J_(NO2)in ambient *** wall loss rates for NO,NO_(2),and O_(3)were 0.47×10^(-4),0.37×10^(-4),and 1.17×10^(-4)min^(-1),while wall loss of toluene was obsoletely found in a 6 hr *** particle number wall loss rates are(0.01-2.46)×10^(-3)min^(-1)for 40-350 nm with an average lifetime of more than one day.A series of toluene photooxidation experiments were carried out in absence of NO_xunder dry *** results of the simulation experiments demonstrated that the chamber is well designed to simulate photolysis progress in the atmosphere.

关键词： Smog chamber Gas-phase oxidation Chamber characterization Chemical mechanism

One-step pore diffusion mechanism of Li^(+) in solid electrolyte interphase for fast-charging lithium-ion battery

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Rare Metals 2024年第7期43卷 3438-3440页

作者： Shan wang Shu-yuan Liu Alireza Khataee Ke-Zhen qi College of Pharmacy Dali UniversityDali 671000China Research Laboratory of Advanced Water and Wastewater Treatment Processes Department of Applied ChemistryFaculty of ChemistryUniversity of TabrizTabriz 51666-16471Iran Peoples'Friendship University of Russia(RUDN University) Moscow117198Russian Federation

Li^(+) transport in solid electrolyte interphase is recognized as important factor,which has become a research ***,an one-step pore diffusion mechanism for Li^(+) transport through solid electrolyte interphase was proposed,which was different from previous two-step *** one-step pore diffusion process could effectively eliminate the dynamic limitations of Li^(+) transport in solid electrolyte interphase (SEI) for rapid charging *** work will contribute to the development of rapid charging lithium-ion batteries.

关键词： battery mechanism electrolyte

Anti-explosion performance and dynamic response of an innovative multi-layer composite explosion containment vessel

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Defence Technology（防务技术） 2024年第6期36卷 105-121页

作者： Zhen wang Heng Chen qi yuan Wenbin Gu Xingbo Xie Hongwei Li College of Field Engineering Army Engineering University of PLANanjing 210007China College of Civil Engineering and Architecture Southwest University of Science and TechnologySichuanMianyang 621010China

An innovative multi-layer composite explosion containment vessel(CECV)utilizing a sliding steel platealuminum honeycomb-fiber cloth sandwich is put forward to improve the anti-explosion capacity of a conventional single-layer explosion containment vessel(SECV).Firstly,a series of experiments and finite element(FE)simulations of internal explosions are implemented to understand the basic anti-explosion characteristics of a SECV and the rationality of the computational models and methods is verified by the comparison between the experimental results and simulation *** on this,the CECV is designed in detail and a variety of FE simulations are carried out to investigate effects of the sandwich structure,the explosive quantity and the laying mode of the fiber cloth on anti-explosion performance and dynamic response of the CECV under internal *** results indicate that the end cover is the critical position for both the SECV and *** maximum pressure of the explosion shock wave and the maximum strain of the CECV can be extremely declined compared to those of the *** a result,the explosive quantity the CECV can sustain is up to 20 times of that the SECV can ***,as the explosive quantity increases,the internal pressure of the CECV keeps growing and the plastic deformation and failure of the sandwich structure become more and more severe,yielding plastic strain of the CECV in addition to elastic *** results also reveal that the laying angles of the fiber cloth's five layers have an impact on the anti-explosion performance of the *** example,the CECV with fiber cloth layered in 0°/45°/90°/45°/0°mode has the optimal anti-capacity,compared to 0°/0°/0°/0°/0°and 0°/30°/60°/30°/0°***,owing to remarkable anti-explosion capacity,this CECV can be regarded as a promising candidate for explosion resistance.

关键词： Explosive container Honeycomb-fiber cloth Anti-explosion Aluminum honeycomb core Composite

Development of component stiffness equations for thread-fixed one-side bolt connections to an enclosed rectangular hollow section column under tension

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 568-586页

作者： Fu-Wei WU yuan-qi LI Department of Structural Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

The derivation and validation of analytical equations for predicting the tensile initial stiffness of threadfixed one-side bolts(TOBs),connected to enclosed rectangular hollow section(RHS)columns,is presented in this *** unknown stiffness components are considered:the TOBs connection and the enclosed RHS ***,the trapezoidal thread of TOB,as an equivalent cantilevered beam subjected to uniformly distributed loads,is analyzed to determine the associated *** on the findings,the thread-shank serial-parallel stiffness model of TOB connection is *** analysis of the tensile stiffness of the enclosed RHS face due to two bolt forces,the four sidewalls are treated as rotation constraints,thus reducing the problem to a two-dimensional plate *** to the load superposition method,the deflection of the face plate is resolved into three components under various boundary and load *** to the plate deflection theory of Timoshenko,the analytical solutions for the three deflections are derived in terms of the variables of bolt spacing,RHS thickness,height to width ratio,***,the validity of the above stiffness equations is verified by a series of finite element(FE)models of T-stub *** proposed component stiffness equations are an effective supplement to the component-based method.

关键词： initial stiffness component based method thread-fixed one-side bolt rectangular hollow sections analytical equation

Post-synthetic modifications of MOFs by different bolt ligands for controllable release of cargoes

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Chinese Chemical Letters 2024年第10期35卷 404-407页

作者： Hao wang Meng-qi Pan Ya-Fei wang Chao Chen Jian Xu yuan-yuan Gao Chuan-Song qi Wei Li Xian-He Bu College of New Materials and Chemical Engineering Beijing Key Lab of Special Elastomeric Composite MaterialsBeijing Institute of Petrochemical TechnologyBeijing 102617China School of Materials Science and Engineering National Institute for Advanced MaterialsTKL of Metal and Molecule-Based Material ChemistryNankai UniversityTianjin300350China College of Chemical Engineering Inner Mongolia University of TechnologyHohhot 010051China

Post-synthetic modifications(PSM)have drawn great attention as a vigoroso tool to tune or enhance the performance of metal-organic frameworks(MOFs).However,the current PSM method usually have to sacrifice the porosity of MOFs to enrich their functionality,such as pore space partition(PSP)and postsynthetic elimination and insertion(PSE&I),causing a trade-off in this *** address this issue,we herein propose a new PSM strategy of using the size-matching ligands as the bolts to lock MOFs'pores,which could be anchored onto open metal sites(OMSs)after guest loading through a stepwise *** a result,the loaded cargoes undergo a controlled releasing process with respect to different bolt *** proposed strategy provides a promising way to balance the functionality and porosity of MOFs.

关键词： Post-synthetic modifications Metal-organic frameworks Bolting ligand Control release Cargo

Dynamic transcriptome profiles and novel markers in bovine spermatogenesis revealed by single-cell sequencing

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Journal of Integrative Agriculture 2024年第7期23卷 2362-2378页

作者： yuan Gao Fuxia Bai qi Zhang Xiaoya An Zhaofei wang Chuzhao Lei Ruihua Dang Key Laboratory of Animal Genetics Breeding and Reproduction of Shaanxi ProvinceCollege of Animal Science and TechnologyNorthwest A&F UniversityYangling 712100China College of Life Sciences Northwestern Polytechnical UniversityXi’an 710072China

Testicular development is an important biological process in male and requires interaction between the male germ cells and somatic ***,the mechanisms of testicular development in livestock,particularly in cattle,are poorly ***,cellular heterogeneity hinders the profiling of different cell types at different developmental *** this study,we first performed a single-cell transcriptomic study of the bovine testis development during puberty by using 10×genomics single-cell RNA sequencing(scRNA-seq).By collecting the scRNA-seq data from 11,083 cells from prepubertal and pubertal bovine testes,a high-resolution scRNA-seq atlas was described,identifying 9 somatic and 13 spermatogenic *** also distinguished several stage-specific marker genes for bovine germ cells and somatic cells,such as GRAF2 and MORC1 for SSC(spermatogonial stem cells),HJURP and TCF19 for differentiating spermatogonia,ARSE for immature Sertoli,CLEC12B for mature Sertoli,LOC112441470 for *** conclusion,we have examined the transcription levels and constructed the single-cell developmental maps of germ cells and somatic cells during testicular development in Angus *** datasets provided new insights into spermatogenesis and testicular somatic cell development in cattle.

关键词： scRNA-seq cattle spermatogenesis testis development