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Impact of Polymer matrix on Polymer Mechanochromism from Excited State Intramolecular Proton Transfer

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

作者： Yu Wu Xin Cheng Huan Hu Shui Hu Zhimin ma zhiyong 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 polymers based on non-covalent changes have attracted much attention recently.Herein,we report the impact of inter/intramolecular hydrogen bonds on polymer mechanochromism from the excited state intramolecular proton transfer (ESIPT) process.PhMz-NH2-OH and PhMz=2A are designed and obtained by simple and high-yield synthesis,and are connected into polyurethane and poly(methyl acrylate-co-2-ethylhexyl acrylate),respectively.In the initial state,the PhMz-NH2-OH@PU sample shows blue fluorescence from the excited enol form (E*) excitons,owing to intermolecular hydrogen bonds that interrupt the ESIPT reactions but the PhMz=2A@Pma-2-EA sample expresses cyan fluorescence belonging to the excited keto form (K*) emission,implying that the intramolecular hydrogen bonds matter.Furthermore,under stretching,external force can tune the emission of the PhMz=2A@Pma-2-EA sample from K* to E* state.Though external force can putatively still promote a bond rotation,ESIPT reactions remain equivalently interrupted in both the relaxed and stressed states in a hydrogen-bond donating environment.DFT calculation confirms the force-induced increase in dihedral angle for the transition of ESIPT-on/off.Thus,PhMz-NH2-OH@PU and PhMz=2A@Pma-2-EA showed disparate initial ESIPT states and further different responses/sensitivity to force.This study reports a novel and efficient strategy for enriching mechanochromic investigation and extending the applications of ESIPT reactions.

关键词： Polymer mechanochromism Excited state intramolecular proton transfer Hydrogen bonding Supramolecular chemistry Elastomers

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matrix-Mediated Color-Tunable Ultralong Organic Room Temperature Phosphorescence of 7H-Benzo[c]carbazole Derivatives

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CCS Chemistry 2024年第3期6卷 798-811页

作者： Chen Qian Xue Zhang Zhimin ma Xiaohua Fu Zewei Li Huiwen Jin Mingxing Chen Hong Jiang zhiyong ma Beijing Advanced Innovation Center for Soft matter Science and Engineering State Key Laboratory of Organic–Inorganic CompositesCollege of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029 Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871

Building on the recent systematic research on 1Hbenzo[f]indole(Bd),an important advancement in constructing ultralong organic room temperature(UORTP)materials with a universal strategy via a readily obtained unit(7H-Benzo[c]carbazole,BCz)is proposed in this work.Pure powders of BCz and its derivatives merely exhibit blue fluorescence at ambient condition.However,when BCz and its derivatives are dispersed into polymer or powder matrixes,strong photo-activated green UORTP can be observed from their doped systems at room temperature.Moreover,the UORTP color can be tuned between green and yellow depending on the matrix.The ultralong phosphorescence originates from the generation of charge-separated states via radicals.The matrixes play a key role in both stabilizing charge-separated states and controlling UORTP color.More interestingly,when using polymethyl methacrylate as matrix,the doped films achieve stronger photo-activated ultralong phosphorescence underwater than in air at room temperature.Comparedwith Bd,BCz achieves better performance not only in ultralong phosphorescence properties but also in practical applications.This work gains a deeper insight into the mechanism of UORTP and paves a new approach to applying organic phosphorescent materials to underwater coating and imaging.

关键词： 7H-Benzo[c]carbazole ultralong organic room temperature phosphorescence ion radical matrix-mediated color tunning underwater application

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Unraveling the complexity of polycystic ovary syndrome with animal models

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Journal of Genetics and Genomics 2024年第2期51卷 144-158页

作者： Huanju Liu Mixue Tu zhiyong Yin Dan Zhang Jun ma Feng He Center for Genetic Medicine The Fourth Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310058China Key Laboratory of Women's Reproductive Health of Zhejiang Province and Department of Reproductive Endocrinology Women's HospitalZhejiang University School of MedicineHangzhouZhejiang 310006China Zhejiang Provincial Clinical Research Center for Child Health Women's HospitalZhejiang University School of MedicineHangzhouZhejiang 310006China Clinical Research Center on Birth Defect Prevention and Intervention of Zhejiang Province HangzhouZhejiang 310006China Institute of Genetics Zhejiang University International School of MedicineHangzhouZhejiang 310058China Zhejiang Provincial Key Laboratory of Genetic and Developmental Disorder HangzhouZhejiang 310058China

Polycystic ovary syndrome (PCOS) is a highly familial and heritable endocrine disorder. Over half of the daughters born to women with PCOS may eventually develop their own PCOS-related symptoms. Progress in the treatment of PCOS is currently hindered by the complexity of its clinical manifestations and incomplete knowledge of its etiopathogenesis. Various animal models, including experimentally induced, naturally occurring, and spontaneously arising ones, have been established to emulate a wide range of phenotypical and pathological traits of human PCOS. These studies have led to a paradigm shift in understanding the genetic, developmental, and evolutionary origins of this disorder. Furthermore, emerging evidence suggests that animal models are useful in evaluating state-of-the-art drugs and treatments for PCOS. This review aims to provide a comprehensive summary of recent studies of PCOS in animal models, highlighting the power of these disease models in understanding the biology of PCOS and aiding high-throughput approaches.

关键词： Polycystic ovary syndrome Animal model Genetc manipulation Developmnental progtanning Drug screening

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High power tunable Raman fiber laser at 1.2μm waveband

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Frontiers of Optoelectronics 2024年第1期17卷 1-8页

作者： Yang Zhang Jiangming Xu Junrui Liang Jun Ye Sicheng Li Xiaoya ma zhiyong Pan Jinyong Leng Pu Zhou College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China Nanhu Laser Laboratory National University of Defense TechnologyChangsha 410073China Hunan Provincial Key Laboratory of High Energy Laser Technology National University of Defense TechnologyChangsha 410073China

Development of a high power fiber laser at special waveband,which is difficult to achieve by conventional rare-earth-doped fibers,is a significant challenge.One of the most common methods for achieving lasing at special wavelength is Raman conversion.Phosphorus-doped fiber(PDF),due to the phosphorus-related large frequency shift Raman peak at 40 THz,is a great choice for large frequency shift Raman conversion.Here,by adopting 150 m large mode area triple-clad PDF as Raman gain medium,and a novel wavelength-selective feedback mechanism to suppress the silica-related Raman emission,we build a high power cladding-pumped Raman fiber laser at 1.2μm waveband.A Raman signal with power up to 735.8 W at 1252.7 nm is obtained.To the best of our knowledge,this is the highest output power ever reported for fiber lasers at 1.2μm waveband.Moreover,by tuning the wavelength of the pump source,a tunable Raman output of more than 450 W over a wavelength range of 1240.6–1252.7 nm is demonstrated.This work proves PDF’s advantage in high power large frequency shift Raman conversion with a cladding pump scheme,thus providing a good solution for a high power laser source at special waveband.

关键词： Phosphosilicate fiber Raman fiber laser 1.2μm waveband Wavelength tunable

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A Dual-Cluster-Head Based Medium Access Control for Large-Scale UAV Ad-Hoc Networks

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China Communications 2024年第5期21卷 123-136页

作者： Zhao Xinru Wei Zhiqing Zou Yingying ma Hao Cui Yanpeng Feng zhiyong Key Laboratory of Universal Wireless Communications Ministry of EducationSchool of Information and Communication EngineeringBeijing University of Posts and TelecommunicationsBeijing100876China

Unmanned Aerial Vehicle(UAV)ad hoc network has achieved significant growth for its flexibility,extensibility,and high deployability in recent years.The application of clustering scheme for UAV ad hoc network is imperative to enhance the performance of throughput and energy efficiency.In conventional clustering scheme,a single cluster head(CH)is always assigned in each cluster.However,this method has some weaknesses such as overload and premature death of CH when the number of UAVs increased.In order to solve this problem,we propose a dual-cluster-head based medium access control(DCHmaC)scheme for large-scale UAV networks.In DCHmaC,two CHs are elected to manage resource allocation and data forwarding cooperatively.Specifically,two CHs work on different channels.One of CH is used for intra-cluster communication and the other one is for inter-cluster communication.A markov chain model is developed to analyse the throughput of the network.Simulation result shows that compared with FM-maC(flying ad hoc networks multi-channel maC,FM-maC),DCHmaC improves the throughput by approximately 20%~50%and prolongs the network lifetime by approximately 40%.

关键词： dual cluster head medium access control UAV swarm

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Direct enantioselective reduction of C=C bond of β-polyfluoro-alkylated enones via asymmetric photoredox catalysis

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Science China Chemistry 2024年第6期67卷 2016-2021页

作者： Linghong Zhang Jin ma Xu Ban Xiaowei Zhao Yanli Yin zhiyong Jiang Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province Henan UniversityKaifeng475004China School of Chemistry and Chemical Engineering Henan Normal UniversityPingyuan LaboratoryXinxiang453007China College of Advanced Interdisciplinary Science and Technology Henan University of TechnologyZhengzhou450001China

Direct enantioselective reduction of the C=C bond ofβ-polyfluoro-alkylated enones is an important but long-pending subject in asymmetric catalysis.Here,we report on the viability of visible light-driven cooperative photoredox and chiral hydrogenbonding catalysis to effectively address this challenge,as a variety of products are obtained in high yields(up to 85%)with good to excellent enantioselectivities(up to 98%ee).The formation of thermodynamically favorable enol intermediates after double single-electron reduction represents the center of the success.Additionally,the utility of the current method is validated by the convenient regio-specific and-diverse synthesis of various deuterated derivatives for these products using inexpensive D_(2)O as the deuterium source.

关键词： photoredox catalysis Br?nsted acids asymmetric reduction enantioselective protonation azaarenes

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Geological Context of the SLIM Landing Site

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Journal of Earth Science 2024年第2期35卷 708-711页

作者： Yichen Wang zhiyong Xiao Pei ma Hanxing Ouyang Wei Cao Planetary Environmental and Astrobiological Research Laboratory School of Atmospheric SciencesSun Yat-sen UniversityZhuhai 519000China Chinese Academy of Sciences Center for Excellence in Comparative Planetology Hefei 230026China Planetary Science Institute School of Earth SciencesChina University of GeoscienceWuhan 430074China

INTRODUCTION Japan’s first successful lunar landing mission,Smart Lander for Investigating Moon(SLIM),was landed on the Moon on January 19th,2024.SLIM made a precise landing within 100 m of the targeted landing zone(central coordinates 13.316°S,25.251°E),which is located around the Shioli crater(D=270 m,central coordinates as 13.33°S,25.23°E)in the southwestern ejecta of the Theophilus crater(D=98.6 km,central coordinates as 11.45°S,26.28°E).

关键词： southwestern coordinates SLIM

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Solid Bi_(2)O_(3)-derived nanostructured metallic bismuth with high formate selectivity for the electrocatalytic reduction of CO_(2)

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International Journal of Minerals,Metallurgy and materials 2024年第4期31卷 803-811页

作者： Xiaoyan Wang Safeer Jan zhiyong Wang Xianbo Jin College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072China Engineering Research Center of Organosilicon Compounds&materials Ministry of EducationWuhan 430072China

CO_(2) electrochemical reduction(CO_(2)ER)is an important research area for carbon neutralization.However,available catalysts for CO_(2) reduction are still characterized by limited stability and activity.Recently,metallic bismuth(Bi)has emerged as a promising catalyst for CO_(2) ER.Herein,we report the solid cathode electroreduction of commercial micronized Bi2O3as a straightforward approach for the preparation of nanostructured Bi.At-1.1 V versus reversible hydrogen electrode in a KHCO3aqueous electrolyte,the resulting nanostructure Bi delivers a formate current density of~40 ma·cm^(-2) with a current efficiency of~86%,and the formate selectivity reaches97.6% at-0.78 V.Using nanosized Bi2O3as the precursor can further reduce the primary particle sizes of the resulting Bi,leading to a significantly increased formate selectivity at relatively low overpotentials.The high catalytic activity of nanostructured Bi is attributable to the ultrafine and interconnected Bi nanoparticles in the nanoporous structure,which exposes abundant active sites for CO_(2) electrocatalytic reduction.

关键词： bismuth carbon dioxide electrocatalysis formate solid electroreduction

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Efficacy Differences of First-line EGFR-TKIs Alone vs in Combination with Chemotherapy in Advanced Lung Adenocarcinoma Patients with Sensitive EGFR Mutation and Concomitant Non-EGFR Genetic Alterations

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中国肺癌杂志 2022年第9期25卷 651-657页

作者： Guowei ZHANG Ruirui CHENG Yuanyuan NIU Huijuan WANG Xiangtao YAN Mina ZHANG Xiaojuan ZHANG Jinpo YANG Chunhua WEI zhiyong ma Department of Internal Medicine The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000China Department of Respiratory Medicine The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000China

Background and objective:Epidermal growth factor receptor(EGFR)mutations are often associated with non-EGFR genetic alterations,which maybe a reason for the poor efficacy of EGFR tyrosine kinase inhibitors(TKIs).Here we conducted this study to explore whether EGFR-TKIs combined with chemotherapy would benefit advanced lung adenocarcinoma patients with both sensitive EGFR mutation and concomitant non-EGFR genetic alterations.materials and methods:Cases of advanced lung adenocarcinoma with EGFR mutation combined with concomitant nonEGFR genetic alterations were retrospectively collected.And the patients were required to receive first-line EGFR-TKIs and chemotherapy combination or EGFR-TKIs monotherapy.Demographic,clinical and pathological data were collected,and the electronic imaging data were retrieved to evaluate the efficacy and time of disease progression.Survival data were obtained through face-to-face or telephone follow-up.The differences between the two groups in objective response rate(ORR),disease control rate(DCR),progression-free survival(PFS)and overall survival(OS)were investigated.Results:107 patients were included,including 63 cases in the combination group and 44 cases in the monotherapy group.The ORR were 78%and 50%(P=0.003),and DCR were 97%and 77%(P=0.002),respectively.At a median follow-up of 13.7 mon,a PFS event occurred in 38.1%and 81.8%of patients in the two groups,with median PFS of18.8 mon and 5.3 mon,respectively(Pma with concomitant non-EGFR genetic alterations,combination of TKIs and chemotherapy was significantly superior to EGFR-TKIs monotherapy,which should be the preferred treatment option.

关键词： Lung neoplasms EGFR mutation Concomitant genetic alteration Targeted therapy Chemotherapy

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Contribution of Toll-like receptors to the control of hepatitis B virus infection by initiating antiviral innate responses and promoting specific adaptive immune responses

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Cellular & Molecular Immunology 2015年第3期12卷 273-282页

作者： zhiyong ma Ejuan Zhang Dongliang Yang Mengji Lu Institute of Virology University Hospital Essen University of Duisburg-Essen Essen Germany Department of Infectious Diseases Zhongnan Hospital ofWuhan University Wuhan China Wuhan Institute of Virology Chinese Academy of Sciences Wuhan China Department of Infectious Diseases Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China

It is well accepted that adaptive immunity plays a key role in the control of hepatitis B virus （HBV） infection. In contrast, the contribution of innate immunity has only received attention in recent years. Toll-like receptors （TLRs） sense pathogen-associated molecule patterns and activate antiviral mechanisms, including intracellular antiviral pathways and the production of antiviral effector interferons （IFNs） and pro-inflammatory cytokines. Experimental results from in vitroand in vivo models have demonstrated that TLRs mediate the activation of cellular signaling pathways and the production of antiviral cytokines, resulting in a suppression of HBV replication. However, HBV infection is associated with downregulation of TLR expression on host cells and blockade of the activation of downstream signaling pathways. In primary HBV infection, TLRs may slow down HBV infection, but contribute only indirectly to viral clearance. Importantly, TLRs may modulate HBV-specific T- and B-cell responses in vivo, which are essential for the termination of HBV infection. Thus, TLR agonists are promising candidates to act as immunomodulators for the treatment of chronic HBV infection. Antiviral treatment may recover TLR expression and function in chronic HBV infection and may increase the efficacy of therapeutic approaches based on TLR activation. A combined therapeutic strategy with antiviral treatment and TLR activation could facilitate the restoration of HBV-specific immune responses and thereby, achieve viral clearance in chronically infected HBV patients.

关键词： Hepatitis B virus Toll like receptor Innate immune response Adaptive immune response

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