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π-conjugated chromophore functionalized high-nuclearity titanium-oxo clusters containing structural unit of anatase for photocatalytic selective oxidation of sulfides

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Rare Metals 2024年第4期43卷 1736-1746页

作者： Ling-Rong Liao Dong-Chun Zheng Pin-Xi Ou qi-xin Zhao Wei-min Xuan qi Zheng State Key Laboratory for Modification of Chemical Fibers and Polymer Materials&College of Materials Science and Engineering Donghua UniversityShanghai201620China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials and College of Chemistry and Chemical Engineering Donghua UniversityShanghai 201620China

N-doping has significant influence in manipulating the properties of TiO_(2),and this has stimulated the development of N-donor-functionalized titanium-oxo clusters(TOCs)as molecular models to study the structure-property ***,the structural type and photoresponsive application are still limited for such TOCs,especially regarding the high-nuclearity TOCs that contain structure unit of TiO_(2)for ***,we showed the synthesis of a series of high-nuclearity TOCs 1-3 compounds usingπ-conjugated 1,10-phenanthroline(phen)as chromophore and N-donor functional *** 1 features cocrystal structure composed of one[Ti_(26)]~(2+)and half[Ti_(22)]~(2+),which renders it as the first cocrystallized TOC containing two positively charged species and phen-functionalized TOC showing the highest nuclearity up to 37 Ti *** adjusting the synthetic conditions,the individual{Ti_(22)}and{Ti_(26)}clusters can also be isolated as Compounds 2 and 3,*** core structure of{Ti_(22)}is mainly constructed from four lacunary{Ti_(4)}derived from pentagonal{Ti(Ti)_5}unit,while{Ti_(26)}is built from four complete{Ti(Ti)_5}***,a{Ti_8O_(14)}structure unit of anatase TiO_(2)can be identified in{Ti_(26)}.Based on the unique structural features and proper photophysical and photochemical properties of Compounds 1-3,they are applied for photocatalytic *** to the presence of anatase structure unit in{Ti_(26)}and the synergistic effect from{Ti_(22)}and{Ti_(26)},the catalytic performance presents in the order of Compound 1>Compound 3>Compound *** work provides excellent models to understand the structureproperty relationship from the perspective of cocrystallization and Ti-O binding model and will further promote the application of TOCs as functional catalysts for organic transformation.

关键词： Titanium-oxo cluster Molecular model of anatase TiO_(2) High nuclearity π-conjugated chromophore Photocatalytic sulfoxidation

Nanostructured AlFeO_(3) thin films as a novel photoanode for photoelectrochemical water splitting

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Nano Research 2024年第3期17卷 1075-1085页

作者： xin Sun min Wang qi Geng Shuailin Chen Xiaojun Lv Xunlei Ding Meicheng Li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources School of New EnergyNorth China Electric Power UniversityBeijing 102206China School of Mathematics and Physics North China Electric Power UniversityBeijing 102206China

The earth-abundant and robust aluminum ferrite,AlFeO_(3)(AFO),is mainly studied in the context of ***,we demonstrate that AFO can be used as a stable solar absorber in photoelectrochemical cells for solar water splitting,exhibiting attractive *** is the first report on the photoelectrochemical activity of *** thin-film photoelectrodes prepared by solution-processing methods are composed of vertically oriented thin nanosheets,featuring the rhombohedral symmetry(R3c)and n-type *** as-prepared AFO photoanodes generate a photocurrent density of+0.78 mA·cm^(-2) at 1.23 V *** hydrogen electrode(RHE)with the photocurrent _(onset) potential(U_(onset))close to the flat band potential of 0.5 V *** in the presence of hole ***,the U_(onset) of AFO for solar water splitting coincides with the flat band potential as well,which is rare in n-type inorganic *** also report other properties of AFO associated with photoelectrochemical *** films exhibit a band gap energy of 2.31 eV and positive band edges with low ***,the carrier lifetimes in AFO films are up to millisecond timescales under the mediation of defect *** on the photoelectrochemical behavior and optoelectronic properties,we believe that AFO has great potential for application in photoelectrochemical cells.

关键词： AlFeO_(3) photoanode nanosheets photoelectrochemistry onset potential

Pretreatment can alleviate programmed cell death in mesenchymal stem cells

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World Journal of Stem Cells 2024年第8期16卷 773-779页

作者： xin-xing Wan Xi-min Hu qi Zhang Kun Xiong Department of Endocrinology Third Xiangya HospitalCentral South UniversityChangsha 410013Hunan ProvinceChina Department of Dermatology Xiangya HospitalCentral South UniversityChangsha 410008Hunan ProvinceChina Department of Anatomy and Neurobiology Central South UniversityChangsha 410000Hunan ProvinceChina Department of Anatomy and Neurobiology School of Basic Medical ScienceCentral South UniversityChangsha 410013Hunan ProvinceChina

In this editorial,we delved into the article titled“Cellular preconditioning and mesenchymal stem cell ferroptosis.”This groundbreaking study underscores a pivotal discovery:Ferroptosis,a type of programmed cell death,drastically reduces the viability of donor mesenchymal stem cells(MSCs)after engraftment,thereby undermining the therapeutic value of cell-based ***,the article proposes that by manipulating ferroptosis mechanisms through preconditioning,we can potentially enhance the survival rate and functionality of MSCs,ultimately amplifying their therapeutic *** the crucial role ferroptosis plays in shaping the therapeutic outcomes of MSCs,we deem it im-perative to further investigate the intricate interplay between programmed cell death and the therapeutic effectiveness of MSCs.

关键词： Mesenchymal stem cells Programmed cell death Apoptosis Autophagy Ferroptosis

Incidence Coloring of Outer-1-planar Graphs

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 840-848页

作者： Meng-ke qi xin ZHANG School of Mathematics and Statistics Xidian UniversityXi'an 710071China

A graph is outer-1-planar if it can be drawn in the plane so that all vertices lie on the outer-face and each edge crosses at most one another *** is known that every outer-1-planar graph is a planar *** this paper,we conjecture that every planar graph G has a proper incidence(Δ(G)+2)-coloring and confirm it for outer-1-planar graphs with maximum degree at least 8 or with girth at least ***,we prove that every outer-1-planar graph G has an incidence(Δ(G)+3,2)-coloring,and every outer-1-planar graph G with maximum degree at least 8 or with girth at least 4 has an incidence(Δ(G)+2,2)-coloring.

关键词： incidence coloring outer--planar graph planar graph

Effect of acacetin on inhibition of apoptosis in Helicobacter pyloriinfected gastric epithelial cell line

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3624-3634页

作者： qi-Xi Yao Zi-Yu Li Hou-Le Kang xin He min Kang Department of Gastroenterology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Orthopaedics The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Emergency Luzhou People’s HospitalLuzhou 646000Sichuan ProvinceChina

BACKGROUND Helicobacter pylori(***)infection can cause extensive apoptosis of gastric epithelial cells,serving as a critical catalyst in the progression from chronic gastritis,gastrointestinal metaplasia,and atypical gastric hyperplasia to gastric *** eradication of *** is paramount for ameliorating the pathophysiological conditions associated with chronic inflammation of the gastric mucosa and the primary prevention of gastric ***,which has multifaceted pharmacological activities such as anti-cancer,anti-inflammatory,and antioxidative properties,has been extensively investigated across various ***,the impact and underlying mechanisms of action of acacetin on ***-infected gastric mucosal epithelial cells remain *** To explore the defensive effects of acacetin on apoptosis in ***-infected GES-1 cells and to investigate the underlying *** GES-1 cells were treated with *** and acacetin in *** viability was assessed using the CCK-8 assay,cell mortality rate via lactate dehydrogenase assay,alterations in cell migration and healing capacities through the wound healing assay,rates of apoptosis via flow cytometry and TUNEL staining,and expression levels of apoptosis-associated proteins through western blot *** *** infection led to decreased GES-1 cell viability,increased cell mortality,suppressed cell migration,increased rate of apoptosis,increased expressions of Bax and cle-caspase3,and decreased Bcl-2 ***,acacetin treatment enhanced cell viability,mitigated apoptosis induced by *** infection,and modulated the expression of apoptosis-regulatory proteins by upregulating Bcl-2 and downregulating Bax and cleaved *** Acacetin significantly improved GES-1 cell viability and inhibited apoptosis in ***-infected GES-1 cells,thereby exerting a protective effect on gastric mucosal epithelial cells.

关键词： Gastric epithelial GES-1 cells Helicobacter pylori Infection Acacetin Antibiotic resistance Apoptosis

Dynamic motion of quadrupedal robots on challenging terrain:a kinodynamic optimization approach

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Frontiers of Mechanical Engineering 2024年第3期19卷 23-40页

作者： qi LI Lei DING xin LUO Engineering Research Center of Hubei Province for Clothing Information Wuhan 430200China School of Computer Science and Artificial Intelligence Wuhan Textile UniversityWuhan 430200China State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

The dynamic motion of quadrupedal robots on challenging terrain generally requires elaborate spatial–temporal kinodynamic motion planning and accurate control at higher refresh rate in comparison with regular ***,conventional quadrupedal robots usually generate relatively coarse planning and employ motion replanning or reactive strategies to handle terrain *** resultant complex and computation-intensive controller may lead to nonoptimal motions or the breaking of locomotion *** this paper,a kinodynamic optimization approach is *** generate long-horizon optimal predictions of the kinematic and dynamic behavior of the quadruped robot on challenging terrain,we formulate motion planning as an optimization problem;jointly treat the foot’s locations,contact forces,and torso motions as decision variables;combine smooth motion and minimal energy consumption as the objective function;and explicitly represent feasible foothold region and friction constraints based on terrain *** track the generated motions accurately and stably,we employ a whole-body controller to compute reference position and velocity commands,which are fed forward to joint controllers of the robot’s *** verify the effectiveness of the developed approach through simulation and on a physical quadruped robot *** show that the quadruped robot can successfully traverse a 30°slope and 43% of nominal leg length high step while maintaining the rhythm of dynamic trot gait.

关键词： quadrupedal robot kinodynamic planning nonlinear optimization challenging terrain whole-body control

Evaluation of 3D crustal seismic velocity models in southwest China:Model performance,limitation,and prospects

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Science China Earth Sciences 2024年第2期67卷 604-619页

作者： xin WANG Ling CHEN qi-Fu CHEN Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing100049China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China

Southwest China is a tectonically and seismically active region,witnessing strong deformation due to the collision between the Indian and Eurasian *** the subsurface velocity structure of this region is thus important in understanding the tectonics and geodynamic processes of continental collision and in mitigating seismic *** studies have provided various 3D seismic velocity models in southwest ***,discrepancies exist among these models,and less effort has been made to quantify the reliability and accuracy of these existing velocity *** this study,we use regional 3D waveform simulation to evaluate the performance of various regional crustal 3D velocity models in reproducing observed *** particularly focus on two recent earthquake sequence in the region,the 2021 Yunnan Yangbi MS_(6.4) earthquake sequence and the 2022 Sichuan Luding MS_(6.8) earthquake *** tested 3D velocity models include the Southwest China Community Velocity model V1.0,the Unified Seismic Tomography Models for Continental China Lithosphere V2.0,the adjoint full waveform tomography model of the crustal and upper mantle beneath Eastern Tibetan Plateau,and the shallow seismic structure model beneath continental *** results show that the tested 3D velocity models generally capture well long-period(<0.2 Hz)waveforms,indicating that the 3D models adequately resolve overall large-scale subsurface ***,the 3D synthetics show discrepancies in higher frequencies(0.05–0.3 Hz)and the performance of the 3D velocity models varies from region to region,suggesting that smaller scale heterogeneities are not well *** shallow velocity structures(<10 km)can improve the waveform fitting,emphasizing the importance of incorporating shallow structures in waveform *** full-waveform tomography model shows a slighter better performance than the other models,especially for the body-waves,highlighting the advantages

关键词： Southwest China Seismic tomography models Shallow Structures Waveform simulation Model evaluation

Coupling ideality of standing-wave supermode microresonators

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Photonics Research 2024年第8期12卷 1610-1618页

作者： min WANG YUECHEN LEI ZHI-GANG HU CHENGHAO LAO YUANLEI WANG xin ZHOU JINCHENG LI qi-FAN YANG BEI-BEI LI Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China School of Physics Beihang UniversityBeijing 100191China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Songshan Lake Materials Laboratory Dongguan 523808China

Standing-wave supermode microresonators that are created through the strong coupling between counter-propagating modes have emerged as versatile platforms for sensing and nonlinear *** example,these microresonators have shown potential in nanoparticle sizing and counting,as well as enhancing the single-photon optomechanical coupling rate of stimulated Brillouin ***,it has been observed that the relation between the mode linewidth and on-resonance transmission of the split supermodes differs obviously from that of the non-split *** behavior is typically quantified by the coupling ideality(I),which remains inadequately explored for the standing-wave *** this study,we theoretically and experimentally investigate the coupling ideality of standing-wave supermodes in a commonly employed configuration involving a Si O2microresonator side-coupled to a tapered *** findings demonstrate that,even with a single-mode tapered fiber,the coupling ideality of the standing-wave supermodes is limited to 0.5,due to the strong backscattering-induced energy loss into the counter-propagating direction,resulting in an additional equivalent parasitic *** achieving a coupling ideality of 0.5 presents challenges for reaching over-coupled regimes,it offers a convenient approach for adjusting the total linewidth of the modes while maintaining critically-coupled conditions.

关键词： ideality mode wave

Experimental study on effects of gas flow rate on soot characteristics in diffusion flames coupled with plasma

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Science China(Technological Sciences) 2024年第2期67卷 475-485页

作者： qi DanDan CHEN mingXiao TU xin LIU Dong MIIT Key Laboratory of Thermal Control of Electronic Equipment School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China Advanced Combustion Laboratory School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China Department of Electrical Engineering and Electronics University of LiverpoolLiverpool L693GJUK

This study examined the evolution of morphology and nanostructure of soot particles from the plasma-flame interaction for various gas flow *** current study used both optical diagnostic and sampling methods to explore the soot production and combustion *** particles were characterized at the same positions downstream from the flame zone by thermophoretic sampling and transmission electron ***,X-ray diffraction analysis,and thermogravimetric analysis were performed to study the nanostructure and oxidation reactivity of soot.A reduction in soot concentration was found with the plasma addition,which illustrated an inhibition effect of plasma on soot *** increased gas flow rate promoted soot concentration since a growing number of carbons participated in the combustion *** on the gas flow rate(carbon content)variation and plasma activation,either liquid-like soot material with irregularly shaped protrusions or chain-like structure,or a mixture of both,were generated from the diffusion *** soot produced by plasma-flame interaction also demonstrated a high correlation between nanostructure and *** soot from lower carbon content with plasma activation had a shorter fringe length and larger fringe tortuosity related to higher oxidation *** the contrary,soot from the highest carbon content without plasma-flame interaction exhibited prevalent fullerene-like nanostructures with evident large or small shells and also had a higher carbonization degree resulting in lower oxidation reactivity.

关键词： soot characteristics gas flow rate plasma diffusion flames