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STABILITY AND CONVERGENCE OF STEPSIZE-DEPENDENT LINEAR MULTISTEP METHODS FOR NONLINEAR DISSIPATIVE EVOLUTION EQUATIONS IN BANACH SPACE

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Journal of Computational Mathematics 2024年第2期42卷 337-354页

作者： Wansheng Wang department of Mathematics Shanghai Normal UniversityShanghai 200234China

Stability and global error bounds are studied for a class of stepsize-dependent linear multistep methods for nonlinear evolution equations governed by ω-dissipative vector fields in Banach *** break through the order barrier p≤1 of unconditionally contractive linear multistep methods for dissipative systems,strongly dissipative systems are *** employing the error growth function of the methods,new contractivity and convergence results of stepsize-dependent linear multistep methods on infinite integration intervals are provided for strictly dissipative systems(ω<0)and strongly dissipative *** applications of the main results to several linear multistep methods,including the trapezoidal rule,are *** theoretical results are also illustrated by a set of numerical experiments.

关键词： Nonlinear evolution equation Linear multistep methods ω-dissipative operators Stability Convergence Banach space

Facile synthesis of a tumor microenvironment-responsive nanomaterial with metallic polyphenol-encapsulated for enhanced synergistic therapy

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Journal of Rare Earths 2024年第10期42卷 1895-1902页

作者： Kaige Yu Nuo Kou Shouqiang Zhang Tianqi Cao Hanqing Wu Jing Zhou department of chemistry Capital Normal University College of Teacher Education Capital Normal University

The tumor microenvironment（TME） differs from normal tissue cells in its physiological and biochemical *** construction of TME-responsive nanoplatforms requires a tedious preparation process and complex multicomponent *** this work,Er@EGCG-Cu,a TME-responsive nanoplatform,was simply and rapidly synthesized by combining rare earth-doped nanomaterials（NaLuF4:Yb,Er） with EGCG-Cu which is based on the ability of metal ions to coordinate with polyphenols to form a metal-phenolic network（MPN） *** MPN structure is then destroyed under an acidic TME,releasing the chemotherapy（CT） drug EGCG,which can cause apoptosis,CuxSyis generated by combining Cu2+with H2S overexpressed in human colorectal cancer cells and can be used for photothermal therapy（PTT）.Cell experiments show that laser irradiation improves the CT/PTT synergistic effect of Er@*** study has significance for the construction of TME-responsive nanomedicines with simple and rapid preparation for synergistic therapy.

关键词： Metal-polyphenol networks Nanomaterials Rare earths Synergistic therapy Tumor microenvironment

Al-containing Ge-rich IWV:rapid synthesis via interzeolite transformation and application in Baeyer-Villiger oxidation

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Science China chemistry 2024年第7期67卷 2282-2291页

作者： Meichen Jiao Chunmin Jia Hao Xu Peng Wu Xian-Ming Zhang School of chemistry&Material Science Shanxi Normal UniversityTaiyuan 030006China shanghai Key Laboratory of Green chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China School of chemistry Taiyuan University of TechnologyTaiyuan 030024China

Ge-containing Lewis acidic zeolites are typically synthesized using a conventional hydrothermal strategy from amorphous silica sources,through a long time-and energy-consuming approach limiting their wide *** study reports a rapid synthesis strategy for a series of IWV aluminogermanosilicate zeolites(T-x-Al)with a wide range of Si/Ge molar ratios(5–15)by interzeolite transformation of dealuminated FAU(DA-FAU).Notably,Ge-rich IWV could be obtained with crystallization time as short as one day by the equimolecular Si/Ge ratio *** effect of synthetic parameters was investigated and the obtained T-x-Al samples were characterized by XRD,SEM,EDS,ICP,^(29)Si and^(27)Al MAS NMR,FTIR,and N_(2)physisorption *** with a previously reported IWV germanosilicate(H-3),T-x-Al displayed a better catalytic activity in Baeyer-Villiger(BV)oxidation,attributed to the presence of the active framework Ge sites with the assistance of the extraframework Al *** cyclic catalysis tests revealed that the presence of framework Al species contributed to the stability of the ***,T-x-Al,with 14-membered ring(MR)supercages,outperformed the typical 12-MR Sn-beta catalyst in the BV oxidation of large ketone-like 2-admantanone,indicating a promising potential application in the macromolecular catalytic process.

关键词： Ge-rich IWV interzeolite transformation Al assistance Baeyer-Villiger oxidation

SO_(2)-Insertion induced enantioselective oxysulfonylation to access β-chiral sulfones with quaternary carbon stereocenters

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Science China chemistry 2024年第3期67卷 908-913页

作者： Jun Zhang Xuefeng Wang Peiqi Wang Jiayuan Fang Shaoyu Li Jie Wu School of Pharmaceutical and Chemical Engineering&Institute for Advanced Studies Taizhou UniversityShanghai 200438China department of chemistry Fudan UniversityShanghai 200438China State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

β-Chiral sulfones are structural motifs widely found in natural products and bioactive molecules, while also serving as important intermediates for the synthesis of valuable chiral scaffolds. In contrast to the rapid growth of sulfur dioxide insertion chemistry over the last decade, enantioselective catalytic variants for accessing β-chiral sulfones, especially those bearing a quaternary carbon stereocenter, remain rare. Herein, we report an enantioselective copper/bisoxazoline catalyzed oxysulfonylation of alkenes to yield isoxazolinyl-containing β-chiral sulfones bearing quaternary carbon stereocenters with moderate to excellent yields and up to 96:4 er. The advantage and irreplaceability of this sulfur dioxide insertion catalytic system have been demonstrated by achieving transformations clearly unavailable with the previously reported sulfonyl chloride system. Additionally,the recoverability of the new-developed bisoxazoline ligand L9 and its reusability without any erosion of the catalytic activity and enantioselectivity further demonstrate the usefulness of the protocol.

关键词： β-chiral sulfones sulfur dioxide insertion oxysulfonylation copper catalysis enantioselectivity

Small-sized Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C for efficient alkaline and acidic hydrogen evolution reaction by an anchoring calcination strategy

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 95-103页

作者： Jianxia Gu Ying Zhu Haiyan Zheng Chunyi Sun Zhongmin Su department of chemistry Xinzhou Normal UniversityXinzhou 034000China School of chemistry Northeast Normal UniversityChangchun 130024China

A novel,cheap and highly efficient Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C nanocomposite has been successfully constructed through simple one-step carbonization method in a nitrogen *** in the precursor can effectively anchor molybdenum-based Keggin-type polyoxometallate and NiCo-layered double hydroxide through electrostatic and coordination interactions,which avoids the aggregation of catalyst particles during the pyrolysis *** optimization,the obtained Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C possesses small size(3-8 nm),large specific surface area and hierarchical pore *** importantly,Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C presents remarkable hydrogen evolution reaction activity with low overpotentials in 0.5 mol·L^(-1)H_(2)SO_(4)(102.3 mV)and 1 mol·L^(-1)KOH(95 mV)to afford the current density of 10 mA·cm^(-2),as well as small Tafel slopes of 82.49 and 99.92 mV·dec^(-1),***,this catalyst also shows outstanding stability for 12 h without a significant change in current *** excellent catalytic performance of Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C can put down to the synergistic effect between multiple components and the small size of the *** work provides unique insights into the preparation of efficient transition metal-based catalysts for HER.

关键词： polyoxometallates layered double hydroxide transition metal-based electrocatalysts hydrogen evolution reaction

An all-in-one FeO_(x)-rGO sponge fabricated by solid-phase microwave thermal shock for water evaporation and purification

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Journal of Environmental Sciences 2024年第4期138卷 671-683页

作者： Youkun Sun Xiuwen Zhao Xueling Song Jinchen Fan Junhe Yang Yingchun Miao Shuning Xiao School of Materials and chemistry University of Shanghai for Science and TechnologyShanghai 200093China College of chemistry and Environmental Science Qujing Normal UniversityQujing 655011China Prytula Igor Collaborate Innovation Center for Diamond Shanghai Jian Qiao UniversityShanghai 201306China

Developing high-efficiency photothermal seawater desalination devices is of significant importance in addressing the shortage of *** much effort made into photothermal materials,there is an urgent need to design a rapidly synthesized photothermal evaporator for the comprehensive purification of complex ***,we report on all-in-one FeOx-rGO photothermal sponges synthesized via solid-phase microwave thermal *** narrow band gap of the semiconductor material Fe_(3)O_(4) greatly reduces the recombination of electron-hole pairs,enhancing non-radiative relaxation light *** abundantπorbitals in rGO promote electron excitation and thermal vibration between the *** of the surface hydrophilicity and hydrophobicity promotes salt resistance while simultaneously achieving the purification of various complex polluted *** optimized GFM-3 sponge exhibitedan enhanced photothermal conversion rate of 97.3% and a water evaporation rate of 2.04 kg/(m^(2)·hr),showing promising synergistic water purification *** findings provide a highly efficient photothermal sponge for practical applicationsof seawater desalination and purification,as well as develop a super-rapid processing methodology for evaporation devices.

关键词： Desalination Photothermal device Microwave synthesis Water purification FeO_(x)-rGO

Rare earth fluorescent nanoprobes with minimal side effects enable tumor microenvironment activation for chemotherapy

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Journal of Rare Earths 2024年第2期42卷 256-262,I0001页

作者： Tianqi Cao Yuxin Liu Qi Jia Xiaolu Wang Shouqiang Zhang Jing Zhou department of chemistry Capital Normal UniversityBeijing100048China

Chemotherapy,the use of antitumor drugs to kill cancer cells,is currently one of the most effective treatments for ***,serious toxic side effects caused by long-term drug accumulation can cause significant damage to the body,which limits the clinical application of antitumor *** this study,a novel RENPs@DOX-Fe nanoprobe(NP) was constructed by coating the surface of rare earth nanomaterials(NaLuF_(4):Yb,Er) with a complex formed by doxorubicin(DOX) and iron ion(Ⅲ).Due to the low toxicity of anthracycline-metal complexes,the damage to normal cells is *** unique acidic microenvironment in tumor cells facilitates the decomposition and gradual release of DOX from the DOX-Fe *** addition,the DOX-Fe complex can convert near-infrared(NIR) light into heat energy,which promotes the decomposition of the complex,further enhancing the release of DOX in the tumor *** change of ratio fluorescence of rare earth nanomaterials at 660 and 1550 nm after DOX release enables visual monitoring of drug release,which can potentially improve the chemotherapeutic *** vitro experiments established that RENPs@DOX-Fe NPs with NIR illumination had good therapeutic efficacy in *** work provides new insights into designing tumor microenvironment-responsive nanoprobes for chemotherapy with minimal side effects.

关键词： Rare earth nanoprobes Fluorescence Ratiometric imaging DOX Chemotherapy

Exploring luminescence quenching on lanthanide-doped nanoparticles through changing the spatial distribution of sensitizer and activator

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Nano Research 2024年第5期17卷 4517-4524页

作者： Jiwei Li Yao Xie Renrui Sun Junxun Zhou Lining Sun department of chemistry College of SciencesShanghai UniversityShanghai 200444China department of Physics College of SciencesShanghai UniversityShanghai 200444China School of Medicine Shanghai UniversityShanghai 200444China

Luminescence quench is common in overdoped upconversion *** methods have been proposed to counteract the adverse effects of concentration quenching on luminescence,but in upconversion nanoparticles that are highly doped with both sensitizers and activators,the factors that contribute to the diminishing of the emission cannot be summarized by a single ***,a core-shell design is used to spatially separate the sensitizer(Yb^(3+))and activator(Er^(3+))and to modulate the emission by changes in the distribution position as well as the concentration of the dopant ions in order to probe the factors affecting the *** the sensitizer ions are located in the core,the luminescence intensity of the nanoparticles is significantly weaker than that of the other distribution,which implies that the effect of sensitizer and activator on luminescence in the highly doped state has a different and more complex *** intensity of the emission is more affected by Yb^(3+)than Er^(3+),which includes not only the self-quenching of Yb^(3+),but also the dominance in the Yb^(3+)-Er^(3+)*** this finding may provide new ideas for revealing the reasons for the diminished luminescence of highly doped upconversion nanoparticles and thus for enhancing luminescence.

关键词： upconversion luminescence lanthanide ion core-shell nanoparticles concentration quenching cross-relaxation

Nickel-Catalyzed Regio-and Stereoselective Defluorinative Arylation of gem-Difluorinated Cyclopropanes

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Chinese Journal of chemistry 2024年第8期42卷 823-828页

作者： Shutao Qi Yunkai Hua Liangkai Pan Junfeng Yang Junliang Zhang department of chemistry Fudan University2005 Songhu RoadShanghai200438 China Fudan Zhangjiang Institute Shanghai201203 China School of chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan 453007China

Comprehensive Summary,Herein,we report nickel-catalyzed cross-coupling of gem-difluorinated cyclopropanes with boronic acids,providing the corresponding arylated 2-fluoroallylic *** approach used commercially available phosphine ligand Xantphos to obtain monofluorinated alkenes with high regioselectivity and *** studies proposed a Ni(II)-fluoroallyl pathway and excluded the radical pathway.

关键词： Nickel Monofluoroolefin Cyclopropane Regioselectivity Stereoselectivity C-C coupling Cross-coupling Synthetic methods