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Detecting nanoparticles by“listening”

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Frontiers of physics 2023年第5期18卷 113-131页

作者： Haonan chang Jun zhang State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

In the macroscopic world,we can obtain some important information through the vibration of objects,that is,listening to the sound.Likewise,we can also get some information of the nanoparticles that we want to know by the means of“listening”in the microscopic world.In this review,we will introduce two sensing methods(cavity optomechanical sensing and surface-enhanced Raman scattering sensing)which can be used to detect the nanoparticles.The cavity optomechanical systems are mainly used to detect sub-gigahertz nanoparticle or cavity vibrations,while surface-enhanced Raman scattering is a well-known technique to detect molecular vibrations whose frequency generally exceeds terahertz.Therefore,the vibrational information of nanoparticles from low-frequency to high-frequency could be obtained by these two methods.The size of the viruses is at the nanoscale and we can regard it as a kind of nanoparticles.Rapid and ultrasensitive detection of the viruses is the key strategies to break the spread of the viruses in the community.Cavity optomechanical sensing enables rapid,ultrasensitive detection of nanoparticles through the interaction of light and mechanical oscillators and surface-enhanced Raman scattering is an attractive qualitatively analytical technique for chemical sensing and biomedical applications,which has been used to detect the SARS-CoV-2 infected.Hence,investigation in these two fields is of vital importance in preventing the spread of the virus from affecting human’s life and health.

关键词： ultrasensitive sensing cavity optomechanics surface-enhanced Raman scattering

Timing and mechanism of opening the Neo-Tethys Ocean:Constraints from mélanges in the Yarlung Zangbo suture zone

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Science China Earth Sciences 2023年第12期66卷 2807-2826页

作者： Tong LIU Chuanzhou LIU Fuyuan WU Wenbin JI Chang zhang Weiqi zhang Zhenyu zhang State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 10029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Geology Northwest UniversityXi'an 710069China

The evolution and final closure of the Neo-Tethys Ocean are one of the most important geological events that have occurred on Earth since the Mesozoic.However,the evolution of the Neo-Tethys is not well constrained,in particular whether its opening occurred in the Permian or the Triassic and whether a plume was involved with its opening or not.In this study,we present geochronological and geochemical data for mafic igneous rocks in mélanges along the Yarlung Zangbo suture zone(YZSZ)in southern Tibet to constrain the timing and mechanism of opening the Neo-Tethys Ocean.Based on field observations,the YZSZ mélanges can be divided into three segments.The western(west of Zhongba)and eastern(Sangsang-Renbu)segments are composed of ocean plate stratigraphy representing accretionary complexes that formed during subduction of Neo-Tethyan oceanic lithosphere beneath the southern margin of the Asian continent.Mélanges in the central segment(Zhongba-eastern Saga)typically have a siliciclastic matrix,and represent Tethyan Himalayan strata that were structurally mixed with the southern margin of the Asian continent.Based on our and previously published geochemical data,the mafic rocks in the YZSZ mélanges are ocean island basalt(OIB)-like,with ages in the Late Permian-Middle Triassic,the Middle-Late Jurassic,and the Early Cretaceous,respectively.An OIB-like block with an age of ca.253 Ma is identified from the Zhongba mélanges in the western segment,and it is the oldest OIB lithology yet identified in the YZSZ mélanges related to the evolution of the Neo-Tethys Ocean.Geochemical features indicate that this OIB-like block is distinct from typical OIBs and would be formed during continental rifting to incipient seafloor spreading.In the framework of plate divergent-convergent coupling systems and based on literature data for early Middle Triassic seamounts,radiolarian cherts,and normal mid-ocean ridge basalt-like oceanic crust,we conclude that opening of the Yarlung Zangbo Neo-Tethys Ocean would mainly occur at~250–243 Ma in th

关键词： Neo-Tethys Ocean Wilson Cycle Yarlung Zangbo suture zone Mélange Ocean island basalt Tethyan geodynamics

Preface to the Special Issue:Additive Manufacturing—Expanding Production Horizon

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 1-2页

作者： Lai-Chang zhang Centre for Advanced Materials and Manufacturing School of EngineeringEdith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

Additive manufacturing(AM),commonly known as 3D printing,has become a transformative technology that has a profound impact on various industrial sectors.AM encompasses a set of techniques for building objects layer by layer from digital models.Unlike conventional subtractive manufacturing methods that involve removing material from large blocks,AM adds material incrementally,providing unprecedented design flexibility and efficiency.

关键词： removing printing Expanding

Investigation of MXenes as oxygen reduction electrocatalyst for selective H_(2)O_(2) generation

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Nano Research 2022年第5期15卷 3927-3932页

作者： Xiao Huang Min Song Jian zhang Jingjing zhang Wei Liu Chang zhang Wang zhang Deli Wang Key Laboratory of Material Chemistry for Energy Conversion and Storage(Huazhong University of Science and Technology) Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China College of Materials Science and Engineering Shenzhen UniversityShenzhen 518055China

Two-electron oxygen reduction reaction(ORR)catalysts are essential for the electrosynthesis of hydrogen peroxide(H_(2)O_(2)).MXenes,a rising family of two-dimensional(2D)transition metal carbides,have been extensively studied for energy storage and(photo)electrocatalysis due to their rich chemical compositions and tunable electronic structures.In this work,three representative MXenes of Ti_(3)C_(2)T_(x),V_(2)CTX,and Nb_(2)CTX were selected for H_(2)O_(2)electrosynthesis and we found that MXenes are inherent two-electron ORR catalysts with high H_(2)O_(2)selectivity.In addition,this work critically evaluates their electrocatalytic activity and stability.Interestingly,Nb_(2)CT_(x)catalyst maintains better electrocatalytic activity and higher stability for a long time test,although the stability of Ti_(3)C_(2)T_(x)and V_(2)CT_(x)catalysts is poor owing to the metal dissolution property of Ti and V in alkaline media.Moreover,the assembled device based on Nb2CTx catalyst presents a high H2O2 production and a rapid organic dye decoloration ability.

关键词： electrosynthesis hydrogen peroxide oxygen reduction reaction MXenes

Herschel Investigation of Cores and Filamentary Structures in the Perseus Molecular Cloud

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Research in Astronomy and Astrophysics 2022年第5期22卷 109-120页

作者： Chang zhang Guo-Yin zhang Jin-Zeng Li Xue-Mei Li National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Physics Guizhou UniversityGuiyang 550025China

Cores and filamentary structures are the prime birthplaces of stars,and play key roles in the process of star formation.Latest advances in the methods of multi-scale source and filament extraction,and in making highresolution column density map from Herschel multi-wavelength observations enable us to detect the filamentary network structures in highly complex molecular cloud environments.The statistics for physical parameters shows that core mass strongly correlates with core dust temperature,and M/L strongly correlates with M/T,which is in line with the prediction of the blackbody radiation,and can be used to trace evolutionary sequence from unbound starless cores to robust prestellar cores.Crest column densities of the filamentary structures are clearly related with mass per unit length(M_(line)),but are uncorrelated by three orders ranging from~10^(20) to~10^(22) cm^(-2) with widths.Full width at half maximum has a median value of 0.15 pc,which is consistent with the 0.1 pc typical inner width of the filamentary structures reported by previous research.We find 70%of robust prestellar cores(135/199)embedded in supercritical filaments with M_(line),>16 M⊙pc^(-1),which implies that the gravitationally bound cores come from fragmentation of supercritical filaments.On the basis of observational evidence that the probability distribution function with power-law distribution in the Perseus south is flatter than in the north,the number of young stellar objects in the south is significantly less than that in the north,and dust temperature is different.We infer that the south region is more gravitationally bound than the north region.

关键词： star forming regions-molecular clouds-interstellar filaments

In situ autophagy regulation in synergy with phototherapy for breast cancer treatment

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ACTA PHARMACEUTICA SINICA B 2024年第5期14卷 2317-2332页

作者： zhang, Huijuan chang, Junbiao zhang, Zhenzhong Hou, Lin Zhengzhou Univ Sch Pharmaceut Sci Zhengzhou 450001 Peoples R China Key Lab Targeting Therapy & Diag Crit Dis Zhengzhou 450001 Peoples R China Collaborat Innovat Ctr New Drug Res & Safety Evalu Zhengzhou 450001 Peoples R China Zhengzhou Univ Sch Chem & Mol Engn Zhengzhou 450001 Peoples R China

Autophagy is an important factor in reducing the efficacy of tumor phototherapy (including PTT and PDT). Accurate regulation of autophagy in tumor cells is a new strategy to improve the antitumor efficiency of PTT/PDT. This project intended to construct a tumor-activated autophagy regulator to efficiently block PTT/PDT-induced autophagy and realize synergistic sensitization to tumor phototherapy. To achieve this goal, we first synthesized TRANSFERRIN (Tf) biomimetic mineralized nanotellurium (Tf-Te) as photosensitizer and then used disulfide bond reconstruction technology to induce Tf-Te self-assembly. The autophagy inhibitor hydroxychloroquine (HCQ) and iron ions carried by Tf were simultaneously loaded to prepare a tumor-responsive drug reservoir Tf-Te/HCQ. After entering breast cancer cells through the "self-guidance system", Tf-Te/HCQ can generate hyperpyrexia and ROS under NIR laser irradiation, to efficiently induce PTT/PDT effect. Meanwhile, the disulfide bond broke down in response to GSH, and the nanoparticles disintegrated to release Fe 2 & thorn; and HCQ at fixed points. They simultaneously induce lysosomal alkalinization and increased osmotic pressure, effectively inhibit autophagy, and synergistically enhance the therapeutic effect of phototherapy. In vivo anti -tumor results have proved that the tumor inhibition rate of Tf-Te/HCQ can be as high as 88.6% on 4T1 tumorbearing mice. This multifunctional drug delivery system might provide a new alternative for more precise and effective tumor phototherapy. 2024 The Authors. Published by Elsevier B.V. on behalf of Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. This is an open access article under the CC BY -NCND license (http://***/licenses/by-nc-nd/4.0/).

关键词： Autophagy Tumor phototherapy Synergistic sensitization HCQ TRANSFERRIN Disulfide bond reconstruction GSH Biomimetic mineralized nano-tellurium NANOPLATFORM THERAPY

Environmental arsenic(As)and its potential relationship with endemic disease in southwestern China

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Journal of Environmental Sciences 2024年第5期139卷 46-59页

作者： Donglin Li Hucai zhang Fengqin chang Lizeng Duan Yang zhang Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental ScienceYunnan UniversityKunming 650500China Southwest United Graduate School Kunming 650500China

Many cases of an unknown disease exhibiting the clinical features of limb gangrene,blisters,ulceration,and exfoliation have been reported in Daping village(DV)in southwestern China.However,the pathogenesis is unknown and has puzzled doctors for many years.A preliminary study on heavy metals and symptoms indicated that arsenic might pose the greatest threat to the health of local residents.Here,to explore the sources of and factors influencing arsenic enrichment in DV,whose residents exhibit signs of arsenic poisoning,the As contents in soil,water,and plants were systematically measured.The results indicated high As contents in plant and soil samples obtained from the area,and the source of As may be linked to the weathering of black shale rock.Ingestion of soil and consumption of plants were the two main As exposure pathways among children and adults,respectively,and children exhibited a higher health risk than adults.We presume and emphasize that when extreme drought events occur,humans might face unusual risks resulting from exposure to toxic elements and the direct consumption of highly polluted water.Our study provides a new perspective and sheds light on the environmental geochemistry and health links of this disease.

关键词： Endemic disease Arsenic(As) Risk assessment Black shale Climate change

Bismuth chloride@mesocellular carbon foam nanocomposite cathode materials for rechargeable chloride ion batteries

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Chinese Chemical Letters 2022年第4期33卷 2200-2204页

作者： Chang zhang Shijiao Sun Meifen Wu Xiangyu Zhao College of Materials Science and Engineering Nanjing Tech UniversityNanjing 211816China CAS Key Laboratory of Materials for Energy Conversion Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Jiangsu Collaborative Innovation Center for Advanced Inorganic Functional Composites Nanjing Tech UniversityNanjing 211816China

Chloride ion batteries(CIB) are considered to be one of the most promising energy storage devices. As cathode materials for CIBs, metal chlorides have many advantages, such as high theoretical energy density, abundant elemental resources and ideal discharge voltage plateau. However, the dissolution and huge volume change of metal chlorides during cycling lead to considerable short lifespan, which limits their potential application for CIBs. Herein, the bismuth chloride nanocrystal is confined in mesocellular carbon foam matrix by a new vacuum impregnation approach. The mesocellular carbon foam with large interconnected pores(15.7 or 23.2 nm) may buffer the large volume variation of bismuth chloride during charge and discharge, giving rise to significantly enhanced electrochemical performance. The as-prepared bismuth chloride@mesocellular carbon foam cathode delivered an initial discharge capacity of 298 m Ah/g and a reversible capacity of 91 m Ah/g after 60 cycles. In contrast, the pure bismuth chloride cathode almost cannot discharge after 30 cycles. This is the first report that the metal chloride cathode can achieve a prolonged cycling in CIBs.

关键词： Chloride ion batteries Cathode materials Bismuth chloride Mesocellular carbon foam Electrochemistry

Fixed-Time Stabilization of a Class of Strict-Feedback Nonlinear Systems via Dynamic Gain Feedback Control

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IEEE/CAA Journal of Automatica Sinica 2023年第2期10卷 403-410页

作者： Chenghui zhang Le chang Lantao Xing Xianfu zhang IEEE the School of Control Science and Engineering Shandong UniversityJinan 250012China the School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

This paper presents a novel fixed-time stabilization control(FSC)method for a class of strict-feedback nonlinear systems involving unmodelled system dynamics.The key feature of the proposed method is the design of two dynamic parameters.Specifically,a set of auxiliary variables is first introduced through state transformation.These variables combine the original system states and the two introduced dynamic parameters,facilitating the closed-loop system stability analyses.Then,the two dynamic parameters are delicately designed by utilizing the Lyapunov method,ensuring that all the closed-loop system states are globally fixed-time stable.Compared with existing results,the“explosion of complexity”problem of backstepping control is avoided.Moreover,the two designed dynamic parameters are dependent on system states rather than a time-varying function,thus the proposed controller is still valid beyond the given fixedtime convergence instant.The effectiveness of the proposed method is demonstrated through two practical systems.

关键词： Dynamic gain feedback control fixed-time stabilization strict-feedback nonlinear system