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Science China chemistry 2024年第2期67卷 542-550页

作者： Min Chen Longqing Yang Yuzhen Li Yinhe Qu Guihua Pan Xiaoming Feng Xiaohua Liu Key laboratory of Green chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu610064China

A highly efficient asymmetric allylic alkylation of cyclic and acyclic carbon nucleophiles with vinyl epoxides has been developed,which exhibits good functional group compatibility,high atomic and step *** protocol utilizes a strategy of synergistic catalysis with a chiral N,N'-dioxide/Ni~Ⅱ complex and an achiral Pd~0 catalyst,generating a series of multisubstituted allylic alcohols with a quaternary carbon stereocenter in high yield and excellent regio-,Z/E-and enantioselectivity under mild *** transformations of the product demonstrate the potential utility of this protocol in the synthesis of allyl alcohol derivatives and natural product *** studies revealed that the N,N′-dioxide/metal complexes play an important role in controlling the Z/E-and *** density functional theory(DFT) calculations further demonstrated that multiple C–H···π interactions between the aromatic rings of the two substrates and the amide moiety in the ligand stabilized the dominant transition state.

关键词： asymmetric allylic alkylation synergistic catalysis vinyl epoxides allyl alcohol multiple weak interactions

Dark Matter Search in Dwarf Irregular Galaxies with Ten Years of Data from the Ice Cube Neutrino Observatory

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Research in Astronomy and Astrophysics 2024年第3期24卷 75-82页

作者： Yi-Fei Lü Ben-Yang Zhu Rong-Lan Li Xue-Kang Guo Tian-Ci Liu Yong-Bo Huang Yun-Feng Liang Guangxi Key laboratory for Relativistic AstrophysicsSchool of physical Science and TechnologyGuangxi University Nanning 530004China

Dwarf irregular galaxies(dIrrs),as rotationally supported systems,have more reliable J-factor measurements than dwarf spheroidal galaxies and have received attention as targets for dark matter detection in recent *** this paper,we use 10 yr of IceCube muon-track data and an unbinned maximum-likelihood-ratio method to search for neutrino signals beyond the background from the directions of seven dIrrs,aiming to detect neutrinos produced by heavy annihilation dark *** do not detect any significant *** on such null results,we calculate the upper limits on the velocity-averaged annihilation cross section for 1 TeV–10 PeV dark *** limits,although weaker than the strictest constraints in the literature in this mass range,are also a good complement to the existing results considering the more reliable J-factor measurements of dIrrs.

关键词： (cosmology) dark matter-cosmology theory-galaxies dwarf

Synthesis and reactivity of cobalt dinitrogen complex supported by nonsymmetrical pincer ligand

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Chinese Chemical Letters 2024年第7期35卷 259-263页

作者： Yuanjin Chen Xianghui Shi Dajiang Huang Junnian Wei Zhenfeng Xi Beijing National laboratory for Molecular Sciences(BNLMS) Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of ChemistryPeking UniversityBeijing 100871China State Key laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryShanghai 200032China

A nonsymmetrical PNN pincer ligand[6-(^(t)Bu_(2)PNH)C_(5)H_(4)N-2-(3-Mes)C_(3)H_(2)N_(2)]and its corresponding cobalt-N_(2)complex were synthesized and *** the stoichiometric reaction of the PNN ligand lithium salt with CoCl_(2),the complex 3,(PNN)CoCl,was ***,reduction of 3 with NaBHEt3under a dinitrogen atmosphere yielded complex 5,(PNN)Co(Ⅰ)(η^(1)-N_(2)).Single-crystal X-ray analysis,IR spectrum,and DFT calculations revealed that the dinitrogen in 5 was only weakly reduced by the cobalt *** reactions of 5 with carbon monoxide and 2,6-dimethylphenyl isocyanide gave carbonyl and isocyanide complexes 6 and 7 with the release of N_(2),***,these cobalt complexes,especially complex 5,demonstrated the capacity to convert dinitrogen to N(TMS)_(3)with moderate efficiency.

关键词： Dinitrogen fixation Dinitrogen transformation Nonsymmetrical pincer ligand Cobalt complex Catalytic silylamine formation

Pd@Ir-LOD multienzyme utilizing endogenous lactate consumption cooperates with photothermal for tumor therapy

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Nano Research 2024年第1期17卷 270-281页

作者： Zichen Ye Yun Li Jingchao Li Xinyan Hu Jinyang Zheng Gongxin Zhang Sijin Xiang Tianbao Zhu Zhide Guo Xiaolan Chen State Key laboratory for physical chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials and Engineering Research Center for Nano-Preparation Technology of Fujian ProvinceCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State Key laboratory of Molecular Vaccinology and Molecular Diagnostics&Center for Molecular Imaging and Translational Medicine School of Public Health Xiamen UniversityXiamen 361102China The High Educational Key laboratory for Biomedical Engineering&Key laboratory of Fire Retardant Materials of Fujian Province Department of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361102China

Lactic acid(LA)plays a major role in the occurrence,development,and spread of *** by its high accumulation in tumor site,a novel lactate oxidase(LOD)conjugated two-dimensional Pd@Ir nanoplatform(Pd@Ir-LOD,PIL)was fabricated to combine cascade reaction with photothermal for tumor *** detail,the overexpressed LA in tumor microenvironment(TME)was a key factor to activate the PIL-based cascade reaction:(1)Plenty of H_(2)O_(2)could be generated from LA by the catalysis of LOD with O_(2);(2)potent·OH was produced from H_(2)O_(2)due to the peroxidase(POD)-like activity of PIL;(3)meantime,PIL’s catalase(CAT)-like activity could decompose part H_(2)O_(2)into O_(2)to achieve the purpose of LA cyclic ***,the reduced glutathione(GSH)scavenging capability of PIL might protect the produced reactive oxygen species(ROS)from being cleared to further improve the cascade therapeutic *** importantly,PIL had excellent photothermal conversion efficiency(37.35%)and manifested a surprising temperature rising effect in *** together,the decreasing LA concentration,accumulation of high-toxic ROS,the depletion of GSH together with the higher intra-tumoral temperature potently enhanced in vivo antitumor ***,a promising therapeutic tactic based on PIL integrating endogenous LA consumption,chemodynamic therapy(CDT),and photothermal therapy(PTT)has been put forward.

关键词： lactate oxidase chemodynamic therapy photothermal therapy cascade reaction tumor microenvironment

Simplified p-i-n Perovskite Solar Cells with a Multifunctional Polyfullerene Electron Transporter

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Chinese Journal of Polymer Science 2024年第8期42卷 1060-1066页

作者： Fei-Fei Wang Tian-Xiao Liu Ze-Wei Cui Ling-Yuan Wang Yun-Jie Dou Xiao-Yu Shi Si-Wei Luo Xiao-Dong Hu Zhi-Jun Ren Yang-Yang Liu Yu Zhao Shang-Shang Chen State Key laboratory of Coordination chemistry MOE Key Laboratory of High Performance Polymer Materials&TechnologySchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 21003China

In prevailing p-i-n perovskite solar cells(PSCs),solution-processible fullerene molecules are widely used as electron-transporting layers(ETLs)but they typically suffer from poor uniformity and undesirable stability ***,a separate bathocuproine(BCP)layer is needed to block hole tran sfer,increasing fabrication complexity and ***,we address these limitations by develo ping a novel polymeric ETL(named PF BCP)synthesized by polymerizing C_(60)with *** innovative material achieves both efficient electron transport and hole blocking,while its excellent uniformity minimizes interface recombination and enhances ***,our blade-coated PSCs utilizing PFBCP achieve a high power conversion efficiency exceeding 22%and retain 91%of initial efficiency after 1200 h of light *** development not only paves the way for commercially viable PSCs but also opens avenues for future ETL design to realize even more efficient and stable PSCs.

关键词： Polyfullerene Perovskite solar cells Electron transporter Stability

Intramolecular Hydrogen Bond Improved Durability and Kinetics for Zinc‑Organic Batteries

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Nano-Micro Letters 2024年第3期16卷 138-148页

作者： Tianjiang Sun Jun Pan Weijia Zhang Xiaodi Jiang Min Cheng Zhengtai Zha Hong Jin Fan Zhanliang Tao Key laboratory of Advanced Energy Materials chemistry(Ministry of Education) Renewable Energy Conversion and Storage CenterCollege of ChemistryNankai UniversityHaihe Laboratory of Sustainable Chemical TransformationsTianjin 300071People’s Republic of China School of physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore Shanghai Key laboratory of Special Artificial Microstructure Materials and Technology School of Physics Science and EngineeringTongji UniversityShanghai 200092People’s Republic of China

Organic compounds have the advantages of green sustainability and high designability,but their high solubility leads to poor durability of zinc-organic ***,a high-performance quinone-based polymer(H-PNADBQ)material is designed by introducing an intramolecular hydrogen bonding(HB)*** intramolecular HB(C=O⋯N-H)is formed in the reaction of 1,4-benzoquinone and 1,5-naphthalene diamine,which efficiently reduces the H-PNADBQ solubility and enhances its charge transfer in *** situ ultraviolet-visible analysis further reveals the insolubility of H-PNADBQ during the electrochemical cycles,enabling high durability at different current ***,the H-PNADBQ electrode with high loading(10 mg cm^(-2))performs a long cycling life at 125 mA g^(-1)(>290 cycles).The H-PNADBQ also shows high rate capability(137.1 mAh g^(−1)at 25 A g^(−1))due to significantly improved kinetics inducted by intramolecular *** work provides an efficient approach toward insoluble organic electrode materials.

关键词： Zn-organic batteries H-PNADBQ polymer Intramolecular hydrogen bond Reduced solubility Improvedπ-conjugated level

CAOSA-extracted lignin improves enzymatic hydrolysis of cellulose

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Green Energy & Environment 2024年第7期9卷 1101-1111页

作者： Sen Ma Zheng Li Jonathan Sperry Xing Tang Yong Sun Lu Lin Jian Liu Xianhai Zeng College of Energy State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen University Fujian Engineering and Research Centre of Clean and High-valued Technologies for Biomass Xiamen Key Laboratory of Clean and High-valued Utilization of Biomass Centre for Green Chemical Science University of Auckland

The conversion of biomass into sugar platform compounds is very important for the biorefinery industry. Pretreatment is essential to the biomass of the sugar platform, however, the lignin obtained by pretreatment, as a key part of lignocellulose, generally has a passive effect on the enzymatic hydrolysis of cellulose into sugars. In this study, p-TsOH(p-toluenesulfonic acid), DES(Deep eutectic solvent) and CAOSA(cooking with active oxygen and solid alkali) pretreatment ways were used to fraction lignin from bamboo biomass. After CAOSA treatment, the hydrolysis efficiency of the pulp was 95.57%. Moreover, the effect of different treatment methods on lignin properties was studied and the promotion effect of lignin was investigated by adding it to the cellulose enzymatic hydrolysis system. In this work, the results showed that CAOSA-extracted lignin with lower ?(1.31–1.25) had a better adsorption effect on the enzyme protein. p-TsOH-extracted lignin with a larger S/G ratio enhanced the inhibition of enzymatic hydrolysis. In addition, the presence of-COOHs in lignin could reduce its inhibitory effect on cellulose saccharification.

关键词： Biomass pretreatment CAOSA Cellulose hydrolysis Lignin Enzyme

Selective synthesis and physical properties of a bismacrocycle:Cycloparaphenylene-pillar[5]arene

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Chinese Chemical Letters 2024年第3期35卷 273-276页

作者： Yu Zhou Guilin Zhuang Pingwu Du Key laboratory of Precision and Intelligent chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleCAS Key Laboratory of Materials for Energy ConversionDepartment of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310032China

Macrocyclic materials have attracted much attention due to their particular chemical and physical *** we report the precise synthesis and characterization of a new bismacrocycle structure base on cycloparaphenylene(CPP)and pillar[5]arene,named cycloparaphenylene-pillar[5]arenes(CPPn[5]).The bismacrocycle was fully characterized by NMR and *** photophysical properties of CPPn[5]were investigated by UV–vis,and the maximum absorption peak was located at 331 nm,which was consistent with density functional theory(DFT)*** fluorescence spectrum was further studied and the emission peak was maximized at 458 *** computational results indicate the strain energy of CPPn[5]is 27.80 kcal/mol and the HOMO-LUMO gap is 3.39 eV Notably,CPPn[5]showed interesting supramolecular properties.

关键词： Pillararene Cycloparaphenylene Bismacrocycles Supramolecular chemistry

Modularized viromimetic polymer nanoparticle vaccines(VPNVaxs) to elicit durable and effective humoral immune responses

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National Science Review 2024年第3期11卷 200-214页

作者： Zichao Huang Xinyu Zhuang Liping Liu Jiayu Zhao Sheng Ma Xinghui Si Zhenyi Zhu Fan Wu Ningyi Jin Mingyao Tian Wantong Song Xuesi Chen Key laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of Sciences School of Applied chemistry and Engineering University of Science and Technology of China Changchun Veterinary Research Institute Chinese Academy of Agricultural Sciences Jilin Biomedical Polymers Engineering laboratory State Key laboratory of Polymer Physics and chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Virus-like particle(VLP) vaccines had shown great potential during the COVID-19 pandemic, and was thought to be the next generation of antiviral vaccine technology due to viromimetic structures. However,the time-consuming and complicated processes in establishing a current recombinant-protein–based VLP vaccine has limited its quick launch to the out-bursting pandemic. To simplify and optimize VLP vaccine design, we herein report a kind of viromimetic polymer nanoparticle vaccine(VPNVax), with subunit receptor-binding domain(RBD) proteins conjugated to the surface of polyethylene glycol-b-polylactic acid(PEG-b-PLA) nanoparticles for vaccination against SARS-CoV-2. The preparation of VPNVax based on synthetic polymer particle and chemical post-conjugation makes it possible to rapidly replace the antigens and construct matched vaccines at the emergence of different viruses. Using this modular preparation system, we identified that VPNVax with surface protein coverage of 20%–25% had the best immunostimulatory activity, which could keep high levels of specific antibody titers over 5 months and induce virus neutralizing activity when combined with an aluminum adjuvant. Moreover, the polymer nano-vectors could be armed with more immune-adjuvant functions by loading immunostimulant agents or chemical chirality design. This VPNVax platform provides a novel kind of rapidly producing and efficient vaccine against different variants of SARS-CoV-2 as well as other viral pandemics.

关键词： vaccine polymer nanomaterials SARS-CoV-2

Modulating Co-Co bonds average length in Co_(0.85)Se_(1-x)S_(x) to enhance conversion reaction for potassium storage

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Journal of Energy chemistry 2024年第4期91卷 111-121页

作者： Daming Chen Yuchun Liu Pan Feng Xiao Tao Zhiquan Huang Xiyu Zhang Min Zhou Jian Chen Jiangsu Key laboratory of Advanced Metallic Materials School of Materials Science and EngineeringSoutheast UniversityNanjing 211189JiangsuChina Hefei National laboratory for physical Sciences at the Microscale School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026AnhuiChina

While alloying transition metal chalcogenides(TMCs)with other chalcogen elements can effectively improve their conductivity and electrochemical properties,the optimal alloying content is still *** this study,we study the influence of dopant concentration on the chemical bonds in TMC and reveal the associated stepwise conversion reaction mechanism for potassium ion *** to density function theory calculations,appropriate S-doping in Co0.85Se(Co_(0.85)Se_(1-x)S_(x))can reduce the average length of Co-Co bonds because of the electronegativity variation,which is thermodynamically favourable to the phase transition *** optimal Se/S ratio(x=0.12)for the conductivity has been obtained from experimental *** assembled as an anode in potassium-ion batteries(PIBs),the sample with optimized Se/S ratio exhibits extraordinary electrochemical *** rate performance(229.2 mA h g^(-1)at 10 A g^(-1))is superior to the state-of-the-art *** assembled with Prussian blue(PB)as a cathode,the pouch cell exhibits excellent performance,demonstrating its great potential for ***,the stepwise K+storage mechanism caused by the coexistence of S and Se is revealed by in-situ X-ray diffraction and ex-situ transmission electron microscopy ***,this work not only provides an effective strategy to enhance the electrochemical performance of transition metal chalcogenides but also reveals the underlying mechanism for the construction of advanced electrode materials.

关键词： Co_(0.85)Se_(1-x)S_(x) Co-Co bonds Phase transition reactions Optimal Se/s Potassium ion batteries