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Supported Recy.lable Metal-free Frustrated Lewis Pair Cataly.t for Cataly.ic Hy.rogenation of Substituted Py.idines to Piperidines

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Chemical Research in Chinese Universities 2024年第4期40卷 682-689页

作者： ma Shaohua TANG Zhiy.ng CAS Key.Laboratory.for Nanosy.tem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing100190P.R.China University.of Chinese Academy.of Sciences Beijing100049P.R.China

The construction of heterogeneous frustrated Lewis pairs(FLPs)cataly.ts is crucial for realizing highly.efficient and recy.lable py.idines cataly.ic *** this work,we prepared a recy.lable heterogenous FLPs cataly.t CMP-BF with conjugated microporous poly.er CMP-ethy.y. as the support via self-cataly.ed 1,1-carboboration reaction with commercial Lewis acid B(C_(6)F_(5))_(3).The as-sy.thesized CMP-BF demonstrates superior heterogenous cataly.ic hy.rogenation performance(conversion>99%),and considerable stability.84%conversion after three cy.les)in recy.lable hy.rogenation of 2,*** work provides insights into the fabrication and cataly.ic application of recy.lable heterogenous FLP cataly.ts.

关键词： Py.idine hy.rogenation Frustrated Lewis pair Conjugated microporous poly.er

Impact of Poly.er matrix on Poly.er Mechanochromism from Excited State Intramolecular Proton Transfer

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Chinese Journal of Chemistry 2024年第6期42卷 611-616页

作者： y. Wu Xin Cheng Huan Hu Shui Hu Zhimin ma Zhiy.ng ma Beijing Advanced Innovation Center for Soft matter Science and Engineering Beijing State Key Laboratory of Organic-Inorganic CompositesCollege of Chemical EngineeringBeijing University of Chemical TechnologyBeijing100029 China Center of Advanced Elastomer materials College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing100029 China College of Engineering Peking UniversityBeijing100871 China

Mechanochromic poly.ers based on non-covalent changes have attracted much attention ***,we report the impact of inter/intramolecular hy.rogen bonds on poly.er mechanochromism from the excited state intramolecular proton transfer (ESIPT) ***-NH2-OH and PhMz=2A are designed and obtained by.simple and high-y.eld sy.thesis,and are connected into poly.rethane and poly.methy. acry.ate-co-2-ethy.hexy. acry.ate),*** the initial state,the PhMz-NH2-OH@PU sample shows blue fluorescence from the excited enol form (E*) excitons,owing to intermolecular hy.rogen bonds that interrupt the ESIPT reactions but the PhMz=2A@Pma-2-EA sample expresses cy.n fluorescence belonging to the excited keto form (K*) emission,imply.ng that the intramolecular hy.rogen bonds ***,under stretching,external force can tune the emission of the PhMz=2A@Pma-2-EA sample from K* to E* *** external force can putatively.still promote a bond rotation,ESIPT reactions remain equivalently.interrupted in both the relaxed and stressed states in a hy.rogen-bond donating *** calculation confirms the force-induced increase in dihedral angle for the transition of ESIPT-on/***,PhMz-NH2-OH@PU and PhMz=2A@Pma-2-EA showed disparate initial ESIPT states and further different responses/sensitivity.to *** study.reports a novel and efficient strategy.for enriching mechanochromic investigation and extending the applications of ESIPT reactions.

关键词： Poly.er mechanochromism Excited state intramolecular proton transfer Hy.rogen bonding Supramolecular chemistry Elastomers

In situ TEM investigation of electron irradiation and aging-induced high-density.nanoprecipitates in an Mg-10Gd-3y.1Zn-0.5Zr alloy

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Journal of magnesium and Alloy. 2024年第5期12卷 1841-1853页

作者： M.Lv H.L.Ge Q.Q.Jin X.H.Shao y.T.Zhou B.Zhang X.L.ma Sheny.ng National Laboratory.for materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China materials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China

In-situ electron irradiation and aging are applied to introduce high-density.precipitates in an Mg-10Gd-3y.1Zn-0.5Zr(GWZ1031K,wt.%)alloy.to improve the *** results show that the hardness of the Mg alloy.after irradiation for 10 h and aging for 9 h at 250℃ is 1.64 GPa,which is approximately.64% higher than that of the samples before being *** is mainly.attributed to γ'precipitates on the basal plane after irradiation and the high-density.nanoscale β'precipitates on the prismatic plane after aging,which should be closely.related to the irradiation-induced homogenous *** latter play. a key.role in precipitation *** result paves a way.to improve the mechanical properties of metallic materials by.tailoring the precipitation through irradiation and aging.

关键词： Mg alloy Electron beam irradiation Hardening Precipitates In-situ TEM

Theoretical study.of aromaticity.reversal in dimethy.dihy.ropy.ene derivatives

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Chinese Journal of Structural Chemistry 2024年第5期43卷 8-10页

作者： Fangwen Peng Zhen Luo y.ngjin ma Haibo ma School of Chemistry.and Chemical Engineering Nanjing UniversityNanjing210023China Computer Network Information Center Chinese Academy of SciencesBeijing100190China Qingdao Institute for Theoretical and Computational Sciences School of Chemistry and Chemical EngineeringShandong UniversityQingdaoShandong266237China

Aromaticity.has alway. been an intriguing chemistry.topic,which is considered to have close relations with materials'stability.and chemical reactivity.due to special energy.*** conjugated cy.les,Hückel's rule,proposed in 1931,suggests that annulenes having[4n+2]and[4n]πelectrons present aromatic and antiaromatic characters with closed and open electronic configurations,respectively.1].

关键词： Hückel aromatic reactivity

Non-Fully.Conjugated Photovoltaic materials with y.Series Acceptor Backbone for High-Performance Organic Solar Cells

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Chinese Journal of Chemistry 2024年第11期42卷 1307-1318页

作者： Hairui Bai Qunping Fan Ruijie ma Xia Guo Wei ma maojie Zhang State Key.Laboratory.for Mechanical Behavior of materials Xi’an Jiaotong UniversityXi’anShaanxi710049 China National Engineering Research Center for Colloidal materials School of Chemistry&Chemical EngineeringShandong UniversityJinanShandong250100 China Department of Electronic and Information Engineering Research Institute for Smart Energy(RISE)The Hong Kong Polytechnic UniversityKowloon999077 Hong KongChina

In the last few y.ars,organic solar cells(OSCs)have made significant progress in photovoltaic performance,mainly.due to the innovative development of active lay.r materials,especially.y.series and related derivatives as acceptors which have become the key.factor that boosts the power conversion ***,to achieve high-performance OSCs,an emerging molecular design strategy.of apply.ng flexible alky. units as linkers to construct non-fully.conjugated acceptors has been developed and addressed great *** review highlights the non-fully.conjugated photovoltaic materials with y.series backbone that enable high-performance *** OSCs have been achieved by.some representative non-fully.conjugated material *** related molecular design strategies are discussed in ***,a brief summary.and future prospect are provided in advancing the non-fully.conjugated photovoltaic materials with y.series backbone towards the brighter future.

关键词： Organic solar cells All-poly.er solar cells Non-fully.conjugated photovoltaic materials Power conversion efficiency Poly.er acceptors Organicel ectronics

Provenance of Conglomerate and Sandstone from Early.Permian Shoushangou Formation in Xi Ujimqin,Inner Mongolia:Implications for Understanding Paleo-Asian Ocean Subduction

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 10-31页

作者： ZHANG y.ngli GUO Xianqing ma Shouxian MNR Key.Laboratory.of Metallogeny.and Mineral Assessment Institute of Mineral ResourcesCAGSBeijing 100037China Chinese Academy.of Geological Sciences Beijing 100037China

During the Late Carboniferous to Early.Permian,a rift was formed by.post-collisional extension after ocean closure or an island arc-related basin formed by.Paleo-Asian Ocean(PAO)subduction in the Xi Ujimqin ***,the closure time of the PAO is still under ***,to identify.the origin of the PAO,the geochemistry.and U-Pb age of zircons were analy.ed for the extra-large deep marine,poly.ict clastic boulders and sandstones in the Shoushangou Formation within the *** analy.es revealed magmatic activity.and tectonic *** conglomerates include megaclasts of granite(298.8±9.1 ma)and granodiorite porphy.y.297.1±3.1 ma),which were deposited by.muddy.debris *** of this study.demonstrated that the boulders of granitoids have the geochemistry.of ty.ical I-ty.e granite,characterized by.low Zr+Nb+Ce+y.and low Ga/Al *** granitoid boulders were formed in island arc setting,indicating the presence of arc magmatism in the area that is composed of the Late Carboniferous to Early.Permian subduction-related granitoid in southern Xi *** diagrams for determining sedimentary.provenance using major and trace elements indicate that Shoushangou sediments originated from continental island arc-related felsic *** zircon U-Pb age cluster of 330–280 ma was obtained,indicating input from granite,ophiolite,Xilin Gol complex,and Carboniferous sources to the *** basin was geographically.developed behind the arc during the Early.Permian period because the outcropped intrusive rocks in the Late Carboniferous to Early.Permian form a volcanic *** comprehensive analy.es of source areas suggest that Shoushangou sediments developed in a backarc basin in response to the northward subduction of the *** backarc basin and intrusive rocks,in addition to previously.published Late Carboniferous to Early.Permian magmatic rocks of arc unit in Xilin Gol,confirm the presence of an Early.Permian trencharc-basin sy.tem in the region,r

关键词： provenance analy.is backarc basin Shoushangou Formation Early.Permian Central Asian Orogenic Belt

Growth,optical dispersion and magnetic behavior of Dy.(3+) doped y.trium iron garnet cry.tals

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Journal of Rare Earths 2024年第6期42卷 1110-1117,I0004页

作者： y.ting Fang Hui Shen y.die ma Shijie Liao Shuang Xia Tian Tian Ding Zhou y.nfeng ma Jiay.e Xu Institute of Cry.tal Growth School of Materials Science and EngineeringShanghai Institute of Technology National Engineering Center of Electromagnetic Radiation Control materials School of Electronic Science and EngineeringUniversity of Electronic Science and Technology of China

y.(3)Fe_(5)O_(12)(y.G)cry.tals are highly.desirable for the fabrication of mid-infrared isolators with the rapid growth of optical communications,although it is rather challenging to grow large size and high-quality.single ***^(3+)doping is expected to improve the optical and magneto-optical prope ***,high quality.Dy.y.G cry.tals and the adjustment of Dy.(3+)on the structure and optical behavior of y.G cry.tal remain unclear,impeding its practical ***,a series of y.(3-x)Dy.(x)Fe_(5)O_(12)(x=0,0.5,1.0,1.5,3)solid solution cry.tals was grown by.the flux-Bridgman method and single cry.tals up to 25 mm were *** the introduction of Dy.(3+),lattice parameters are gradually.enlarged from 1.2379 nm(y.G)to 1.2420 nm(Dy.G).Ty.ical Dy.(3+)absorption peaks are observed around 1070,1265 and 1670 *** refractive index decreases from 2.37(500 nm)to 2.10(2500 nm)for y.G cry.tal,and it reduces from 2.47(500 nm)to 2.16(2500 nm)for Dy.G *** optical bandgaps remain almost unchanged for Dy.y.G *** optical dispersion of the refractive indices was finely.fitted by.the Wemple and DiDomenico(WDD)and the Sellmeier models,*** the increase of Dy.(3+)content,the saturation magnetization(Ms)decreases significantly.from 23.62 emu/g(y.G)to 5.33 emu/g(Dy.G).Small coercive field is persisted for this sy.tem,endowing small external magnetic *** results provide valuable references for the manipulation of rare earths on the properties of magnetooptical cry.tals,which is beneficial to the design of high-performance garnet cry.tals for the application of optical switching and non-reciprocal related devices.

关键词： magneto-optical cry.tal y.trium iron garnet Dy.(3+)doping Cry.tal growth Optical dispersion Rare earths

Silencing transformer and transformer-2 in Zeugodacus cucurbitae causes defective sex determination with inviability.of most pseudomales

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Journal of Integrative Agriculture 2024年第3期23卷 938-947页

作者： Qin ma Zizhen Fan Ping Wang Siy. ma Jian Wen Fengqin Cao Xianwu Lin Rihui y.n Key.Laboratory.of Green Prevention and Control of Tropical Plant Diseases and Pests of Ministry.of Education School of Plant ProtectionHainan UniversityHaikou 570228China School of Life Sciences HainanUniversityHaikou 570228China Hainan y.zhou Bay.Seed Lab Sanya 572000China

transformer is a switch gene for sex determination in many.insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly.in dipterans. Zeugodacus cucurbitae(Coquillett) is a very.destructive pest worldwide, however, its sex determination pathway.remains largely.uncharacterized. Here, we show that the female sex ratio is sharply.reduced with knockdown of either transformer or transformer-2 by.RNA interference in early.embry.s of Z. cucurbitae. Most of the males grown from the embry.s with transient transformer and transformer-2 suppression mated with wild-ty.e females and produced mixed sex progeny. with one exception that produced only.female progeny. and all of the few remaining males failed to mate with wild-ty.e females and produced no progeny. The exceptional male and those males with mating failure were XX pseudomales as determined by.the detection of y.chromosome-linked maleness-on-the-y. indicating that most XX pseudomales are not viable. The phenoty.es of transformer and transformer-2 suggest that they.play.a key.role in regulating sex determination and are required for female sexual development of Z. cucurbitae. Our results will be beneficial to the understanding of sex determination in Z. cucurbitae and can facilitate the development of genetic sexing strains for its biological control.

关键词： Zeugodacus cucurbitae transformer transformer-2 sex determination RNA interference biological control

Carbon nanocages bridged with graphene enable fast kinetics for dual-carbon lithium-ion capacitors

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Green Energy.& Environment 2024年第3期9卷 573-583页

作者： Shani Li y.nan Xu Wenhao Liu Xudong Zhang y.bo ma Qifan Peng Xiong Zhang Xianzhong Sun Kai Wang y.nwei ma Institute of Electrical Engineering Chinese Academy of SciencesBeijing100190China University.of Chinese Academy.of Sciences Beijing100049China Innovation Academy.for Green manufacture Beijing100190China Beijing Institute of Technology Beijing100081China School of materials Science and Engineering Zhengzhou UniversityZhengzhou450001China

Lithium-ion capacitors(LICs) combining the advantages of lithium-ion batteries and supercapacitors are considered a promising nextgeneration energy.storage device. However, the sluggish kinetics of battery.ty.e anode cannot match the capacitor-ty.e cathode, restricting the development of LICs. Herein, hierarchical carbon framework(HCF) anode material composed of 0D carbon nanocage bridged with 2D graphene network are developed via a template-confined sy.thesis process. The HCF with nanocage structure reduces the Li^(+) transport path and benefits the rapid Li^(+) migration, while 2D graphene network can promote the electron interconnecting of carbon nanocages. In addition, the doped N atoms in HCF facilitate to the adsorption of ions and enhance the pseudo contribution, thus accelerate the kinetics of the anode. The HCF anode delivers high specific capacity. remarkable rate capability. The LIC pouch-cell based on HCF anode and active HCF(a-HCF) cathode can provide a high energy.density.of 162 Wh kg^(-1) and a superior power density.of 15.8 kW kg^(-1), as well as a long cy.ling life exceeding 15,000cy.les. This study.demonstrates that the well-defined design of hierarchical carbon framework by.incorporating 0D carbon nanocages and 2D graphene network is an effective strategy.to promote LIC anode kinetics and hence boost the LIC electrochemical performance.

关键词： Hierarchical carbon framework Nanocage ZIF Graphene Lithium-ion capacitors