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Science China Chemistry 2024年第4期67卷 1224-1228页

作者： Ming-Ming Gan zi-en zhang Yi-Fan zhang Heng zhang Li-Ying Sun Ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China

In this study,we present a supramolecular templating approach for constructing polyimidazolium salt containing crown ether and cyclobutane *** strategy involves the formation of metal-carbene templates,photochemical cycloaddition,and subsequent demetallation of metal *** by the host-guest chemistry between crown ether units and ammonium salts,we successfully fabricated a supramolecular polymer SPN1,which features imidazolium receptors and cyclobutane *** obtained SPN1 demonstrates outstanding reversible stimulus-response,antibacterial behavior and conductivity.

关键词： metal-carbene template crown ether polyimidazolium salt host-guest chemistry

Hierarchical self-assembly of crown ether based metal-carbene cages into multiple stimuli-responsive cross-linked supramolecular metallogel

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Science China Chemistry 2021年第7期64卷 1177-1183页

作者： zi-en zhang Yuan-Yuan An Bo Zheng Jin-Ping Chang Ying-Feng Han College of Chemistry and Materials Science Northwest UniversityXi'an 710127China School of Pharmaceutical Sciences Nanjing Tech UniversityNanjing 211816China

The hierarchical self-assembly(HSA) strategy widely utilized in biological systems has been applied in artificial systems to orchestrate small building blocks into complex functional architectures. The non-interfering interactions glue various building blocks together and produce new species with attractive properties. Herein, we functionalized NHC-based assemblies with orthogonal host–guest interaction to fabricate metal-carbene based supramolecular polymer gel. A series of unique crown etherappended cylinder-like trinuclear AuIhexacarbene assemblies [Au_(3)(L)_(2)](PF_(6))_(3)(L=D1–D4, A1–A4) were synthesized from the corresponding trisimidazolium salts H_(3)-L(PF_(6))_(3)(L=D1–D4, A1–A4) in which the N-wingtip of the imidazole moieties were substituted with three identical crown ether groups of different sizes(B15C5, B18C6, B21C7, DB24C8). The gold carbene assembly is able to complex six ammonium salts without disrupting the underlying metal-carbene cylinders. In addition, the supramolecular polymer metallogel featuring a multiple-responsiveness can be formed by using [Au_(3)(A_(4))_(2)](PF_(6))_(3) appended with DB24C8 as the core and bisammonium salt as the cross-linker. The case of introducing orthogonal interaction to NHC moiety by N-wingtip substitution demonstrates the feasibility and the power of such strategy to expand the NHC-based supramolecular system and endow them with novel properties.

关键词： N-heterocyclic carbene metallogel crown ether orthogonal interaction

Asymptotic Inference in the Random Coefficient Autoregressive Model with Time-functional Variance Noises

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 320-346页

作者： en-wen ZHU zi-wei DenG Han-jun zhang Jun CAO Xiao-hui LIU Department of Mathematics and Statistics Changsha University of Science and TechnologyChangsha 410114China School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105China School of Statistics and Data Science and Key Laboratory of Data Science in Finance and EconomicsJiangxi University of Finance and EconomicsNanchang 330013China

This paper considers the random coefficient autoregressive model with time-functional variance noises,hereafter the RCA-TFV *** first establish the consistency and asymptotic normality of the conditional least squares estimator for the constant *** semiparametric least squares estimator for the variance of the random coefficient and the nonparametric estimator for the variance function are constructed,and their asymptotic results are reported.A simulation study is presented along with an analysis of real data to assess the performance of our method in finite samples.

关键词： random coefficient autoregressive model time-functional variance conditional least squares semiparametric least squares

ziF-8 modified by isocyanate as a photocatalytic antibacterial agent

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Rare Metals 2024年第6期43卷 2708-2718页

作者： Yi-Ning zhang Zhen Pei zi-Hao Wang Chong-en Wang Fen-Fen Liang Li-Qiao Wei College of Architecture Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Interface Science and engineering in Advanced Materials of Taiyuan University of Technology Ministry of EducationTaiyuan 030024China Department of Materials Science and engineering Shanxi Institute of TechnologyYangquan 045000China Shanxi-Zheda Institute of Advanced Materials and Chemical engineering Taiyuan 030000China

Zeolite imidazole skeleton(ziF-8)is a promising option for self-cleaning of building exterior walls due to its large specific surface area,high antibacterial activity and low ***,it suffers from low antibacterial efficiency and yield under visible light *** address the issues,we developed the photocatalytic materials T-ziF-8-TDI(thermally treated-ziF-8-toluene 2,4-diisocyanate)by modifying ziF-8 with thermal oxygen sensitization and chemical *** results show that the yield of T-ziF-8-TDI photocatalytic antibacterial agent is increased to 11.5 times of that of T-ziF-8,while maintaining the crystal structure of T-ziF-8 and thermal stability up to 60℃.Furthermore,T-ziF-8-TDI exhibits extended optical response range to the nearinfrared region,significantly narrowed band gap,improved photogenerated elec tron-hole separation efficiency,reduced recombination rate,and excellent photocatalytic *** the concentration of antibacterial agent is 600 mg·L^(-1),the antibacterial rate of Escherichia coli(***)reaches 99.99%irradiated by visible light for30 min,and when the concentration of antibacterial agent is 200 mg·L^(-1),the antibacterial rate of Staphylococcus aureus(***)reaches 99.99%irradiated by visible light for 25 *** also analyzed the reasons in detail from the aspects of bacterial species and antibacterial mechanism,and proposed the antibacterial mechanism of·O_(2)^(-)and h^(+)as the main active *** findings suggest that T-ziF-8-TDI photocatalytic antibacterial agent has potential for use in self-cleaning of building exterior walls.

关键词： ziF-8 Hot oxygen sensitization Modified by isocyanate Antimicrobial performance Photocatalytic antibacterial mechanism

Spherical Polyelectrolyte Brush Nanoreactor:Preparation of Hollow TiO_(2) Nanospheres and Characterization by Small Angle X-Ray Scattering

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Chinese Journal of Polymer Science 2024年第9期42卷 1393-1400,I0009页

作者： Yu-Hua zhang zi-Yu zhang Xin Liu en-Guang Ma Jiang-Tao Guo Li Li Xu-Hong Guo State Key Laboratory of Chemical engineering East China University of Science and TechnologyShanghai200237China Shandong Provincial Key Laboratory of Monocrystalline Silicon Semiconductor Materials and Technology College of Chemistry and Chemical EngineeringDezhou UniversityDezhou253023China Institute of Bast Fiber Crops&Center of Southern Economic Crops Chinese Academy of Agricultural SciencesChangsha410205China

Titanium dioxide(TiO_(2))hollow nanoparticles present significant potential for photocatalytic applications while their straightforward preparation with precise structure control is still *** work reports the approach to preparing tunable hollow TiO_(2) nanospheres by utilization of spherical polyelectrolyte brushes(SPB)as nanoreactors and *** the preparation,the evolution of the structure was characterized by small angle X-ray scattering(SAXS),and in combination with dynamic light scattering and transmission electron *** formation of TiO_(2) shell within the brush(SPB@TiO_(2))is confirmed by the significant increase of the electron density,and its internal structure has been analyzed by fitting SAXS data,which can be influenced by Titanium precursors and ammonia *** calcining SPB@TiO_(2) in a muffle furnace,hollow TiO_(2) nanospheres are produced,and their transition to the anatase crystal form is triggered,as confirmed by X-ray diffraction *** the advantages of their hollow structure,these TiO_(2) nanospheres exhibit exceptional catalytic degradation efficiency of methylene blue(MB),tetracycline(TC),and 2,4-dichlorophenoxyacetic acid(2,4-D),and also demonstrate excellent recyclability.

关键词： Spherical polyelectrolyte brush Nanoreactor Hollow titanium dioxide X-ray scattering

Modulation of d-orbital to realize enriched electronic cobalt sites in cobalt sulfide for enhanced hydrogen evolution in electrocatalytic water/seawater splitting

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Rare Metals 2024年第2期43卷 511-521页

作者： Jian-Peng Sun Yu Zheng zi-Sheng zhang Xiang-Chao Meng zi-Zhen Li Key Laboratory of Marine Chemistry Theory and Technology(Ministry of Education) College of Chemistry and Chemical EngineeringOcean University of ChinaQingdao266100China Shanxi Institute of energy Taiyuan030600China Department of Chemical and Biological engineering Faculty of EngineeringUniversity of OttawaOttawaONK1N6 N5Canada

Herein,a novel single-atomic Pt doping and interface-rich CoS/Co(OH)_(2)(Pt-CoS/Co(OH)_(2)/C)electrocatalyst has been successfully *** from precise regulation of d-orbital electronic structure modulation on Co site,Pt-CoS/Co(OH)_(2)/C exhibited remarkable HER activity and high stability for hydrogen evolution in splitting both water(73 mV@10 mA·cm^(−2)) and seawater(87 mV@10 mA·cm^(−2)).Notably,atomic Pt doping was introduced into CoS/Co(OH)_(2),which could produce local unbalanced Coulombic force and significantly increased the number of S vacancies,and then expose abundant Co ***,Co(OH)_(2) in Pt-CoS/Co(OH)_(2)/C could act as the adsorption sites for H_(2)O in hydrogen evolution reaction *** functional theory results also proved that atomic Pt doping,S vacancies and Co(OH)_(2) coupling could result in the formation of enriched electronic Co sites and optimize d_(z2) orbital electronic structure,and then realize the depth upward shift of d-band center and enhance the adsorption of H*on Co sites.

关键词： Electrocatalysts Hydrogen evolution reaction Pt-CoS/Co(OH)_(2) d-band center Electronic structure Water/seawater electrolysis

Turning point of organoid transplantation:first-in-human trial of iPSC-derived retinal organoid grafting in patients with retinitis pigmentosa

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Science China(Life Sciences) 2024年第5期67卷 1082-1084页

作者： Chang-Jun zhang zi-Bing Jin Beijing Institute of Ophthalmology Beijing Tongren HospitalCapital Medical UniversityBeijing 100730China

The discovery of induced pluripotent stem cells(iPSCs)has revolutionized the field of disease research,providing a promising platform for studying various *** the last decade,significant progress has been made in combining iPSCs with other cutting-edge technologies to investigate disease mechanisms and develop potential treatments.

关键词： conditions patients retinitis

NUDT5 promotes the growth,metastasis,and Warburg effect of IDH wild-type glioblastoma multiforme cells by upregulating TRIM47

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Asian Pacific Journal of Tropical Biomedicine 2024年第2期14卷 82-92页

作者： zi-Fa zhang Shu-Ming Liu Neurosurgery Department Shanxi Bethune HospitalTaiyuanShanxi Province030022China Shanxi Academy of Medical Sciences TaiyuanShanxi province030022China Emergency Department Taiyuan People’s HospitalTaiyuanShanxi Province030021China

Objective:To explore the regulatory mechanism of NUDT5 in glioblastoma multiforme(GBM).Methods:GEPIA database was used to predict the expressions of NUDT5 and tripartite motif family proteins 47(TRIM47)in GBM ***-qPCR and Western blot analyses were performed to examine NUDT5 expression in GBM ***-229 cell proliferation,migration as well as invasion were estimated by CCK-8,colony formation,wound healing,and Transwell assays following interference with *** assay,L-lactic acid kit,glucose detection kit,and ATP detection kit were applied for the detection of glycolysis-related ***-immunoprecipitation experiment was carried out to verify the relationship between NUDT5 and ***:GEPIA database showed that NUDT5 expression was significantly increased in GBM *** the expression of NUDT5 in GBM cells significantly suppressed the viability,proliferation,invasion,migration,and glycolysis of GBM ***,TRIM47 was highly expressed in GBM cells and interacted with *** of TRIM47 partially reversed the inhibitory effect of NUDT5 downregulation on the proliferation,metastasis,and glycolysis of GBM ***:NUDT5 promotes the growth,metastasis,and Warburg effect of GBM cells by upregulating *** NUDT5 and TRIM47 can be used as targets for GMB treatment.

关键词： Glioblastoma multiforme NUDT5 TRIM47 Growth Metastasis Warburg effect

Semi-supervised remote sensing image scene classification with prototype-based consistency

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Chinese Journal of Aeronautics 2024年第2期37卷 459-470页

作者： Yang LI zhang LI zi WANG Kun WANG Qifeng YU College of Aerospace Science and engineering National University of Defense TechnologyChangsha 410073China

Deep learning significantly improves the accuracy of remote sensing image scene classification,benefiting from the large-scale ***,annotating the remote sensing images is time-consuming and even tough for *** neural networks trained using a few labeled samples usually generalize less to new unseen *** this paper,we propose a semi-supervised approach for remote sensing image scene classification based on the prototype-based consistency,by exploring massive unlabeled *** this end,we,first,propose a feature enhancement module to extract discriminative *** is achieved by focusing the model on the foreground ***,the prototype-based classifier is introduced to the framework,which is used to acquire consistent feature *** conduct a series of experiments on NWPU-RESISC45 and Aerial Image Dataset(AID).Our method improves the State-Of-The-Art(SOTA)method on NWPU-RESISC45 from 92.03%to 93.08%and on AID from 94.25%to 95.24%in terms of accuracy.

关键词： Semi-supervised learning Remote sensing Scene classification Prototype network Deep learning

Carbon nanofibers embedded with Fe-Co alloy nanoparticles via electrospinning as lightweight high-performance electromagnetic wave absorbers

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Rare Metals 2024年第6期43卷 2769-2783页

作者： Wen-Jun Cai Jian-Guo Jiang zi-Dong zhang zi-Xuan Liu Lu-Jiezhang Zhen-Kun Long Ke Bi Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinan 250061China School of Materials Science and engineering Shandong UniversityJinan 250061China energy Institute Qilu University of Technology(Shandong Academy of Sciences)Jinan 250014China State Key Laboratory of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China

As a lot of electromagnetic pollution and interference issues have emerged,to overcome electromagnetic interference,prevent electromagnetic hazards,and develop new high-performance electromagnetic wave(EMW)absorbers have become a significant task in the field of materials *** this paper,a three-dimensional(3D)carbon nanofibers network with core-shell structure,embedded with varied molar ratios of iron and cobalt(4:0,3:1,2:2,1:3,0:4),was effectively synthesized(Fe/Co@C-CNFs)via *** phase,microstructure,magnetic and EMW absorption properties were *** is discovered that Fe/Co@C-CNFs doped with iron:cobalt=1:1 have excellent EMW absorption *** the matching thickness is 1.08 mm,the minimum reflection loss(RL)value is-18.66 dB,while the maximum effective absorption bandwidth(EAB)reaches 4.2 GHz(13.9-18 GHz)at a thickness of 1.22 *** is owing to the absorbers'superior impedance matching and multiple reflections as well as the conductivity,dielectric,and magnetic losses of carbon nanofibers embedded with Fe-Co alloy *** addition,the radar cross section(RCS)of the absorbers has been calculated by CST Studio Suite,showing that the absorbing coating can effectively reduce the RCS at various angles,especially for Fe/Co@C-CNFs doped with iron:cobalt=1:*** findings not only provide new insights for the preparation of light-weight and high-performance electromagnetic wave absorbers,but also contribute to energy storage and conversion.

关键词： Electromagnetic wave(EMW)absorbers Fe/Co@C-CNFs Core-shell structure EMW absorbing mechanism Radar cross section(RCS)