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Friction 2024年第6期12卷 1119-1132页

作者： Song yuan Xiaoguang GUO Hao WANG Renke KANG Shang gao State Key Laboratory of High-performance Precision Manufacturing Dalian University of TechnologyDalian 116024China

The roughness of the contact surface exerts a vital role in *** is still a significant challenge to understand the microscopic contact of the rough surface at the atomic ***,the rough surface with a special root mean square(RMS)value is constructed by multivariate Weierstrass–Mandelbrot(W–M)function and the rubbing process during that the chemical mechanical polishing(CMP)process of diamond is mimicked utilizing the reactive force field molecular dynamics(ReaxFF MD)*** is found that the contact area A/A0 is positively related with the load,and the friction force F depends on the number of interfacial bridge *** the surface roughness will increase the friction force and friction *** model with low roughness and high lubrication has less friction force,and the presence of polishing liquid molecules can decrease the friction force and friction *** RMS value and the degree of damage show a functional relationship with the applied load and lubrication,i.e.,the RMS value decreases more under larger load and higher lubrication,and the diamond substrate occurs severer damage under larger load and lower *** work will generate fresh insight into the understanding of the microscopic contact of the rough surface at the atomic level.

关键词： diamond random roughness reactive force field molecular dynamics(ReaxFF MD) friction Weierstrass-Mandelbrot(W-M)function chemical mechanical polishing(CMP)

Tuning the surface electronic structure of noble metal aerogels to promote the electrocatalytic oxygen reduction

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Journal of Energy Chemistry 2024年第2期89卷 557-564,I0013页

作者： Hongxing yuan Wei gao Xinhao Wan Jianqi Ye Dan Wen State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072ShaanxiChina

The sluggish kinetics of the oxygen reduction reaction(ORR)is the bottleneck for various electrochemical energy conversion *** the electronic structure of electrocatalysts by ligands has received particular attention in deriving valid ORR ***,the surface electronic structure of Ptbased noble metal aerogels(NMAs)was modulated by various organic ligands,among which the electron-withdrawing ligand of 4-methylphenylene effectively boosted the ORR *** calculations suggested the smaller energy barrier for the transformation of O^(*) to OH^(*) and downshift the d-band center of Pt due to the interaction between 4-methylphenylene and the surface metals,thus enhancing the ORR intrinsic *** Pt3Ni and Pt Pd aerogels with 4-methylphenylene decoration performed significant enhancement in ORR activity and durability in different ***,the 4-methylphenylene modified Pt Pd aerogel exhibited the higher halfwave potential of 0.952 V and the mass activity of 10.2 times of commercial Pt/*** work explained the effect of electronic structure on ORR electrocatalytic properties and would promote functionalized NMAs as efficient ORR electrocatalysts.

关键词： Noble metal aerogels Surface electronic structure ORR Electrocatalyst Organic ligands

Melittin enhanced intracellular trehalose with synergistic membrane stabilization of macromolecular protectants for cell cryopreservation

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Science China(Technological Sciences) 2024年第4期67卷 1160-1169页

作者： NIU QingJing gao ShuHui ZHU KongYing REN LiXia yuan XiaoYan School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin 300350China Analysis and Measurement Center Tianjin UniversityTianjin 300072China

Cryopreservation plays an essential role in biobanking and cell therapy,but the physiological toxicity of traditional cryoprotectants such as glycerol and dimethyl sulfoxide(DMSO)has raised safety issues for biomedical ***,a nonreducing disaccharide that accumulates in desiccation-or cold-tolerant organisms,has been considered as a biocompatible ***,a naturally occurring membrane-active cationic peptide,melittin,was utilized to facilitate membraneimpermeable trehalose entry into cells for effective cell ***(ethylene glycol)and poly(vinyl pyrrolidone)were applied as macromolecular protectants to improve the stabilization of cell *** the optimal protocol,the postthaw recovery of human red blood cells in freezing bags at a hematocrit of~50%could achieve 82.9%with favorable cell morphologies and physiological ***,the cryosurvival of L929 fibroblasts reached 84.3%compared to the conventional method using 10%(v/v)*** short,this work by using trehalose and melittin provides a biocompatible solvent-free approach for long-term cryostorage of cells.

关键词： melittin intracellular trehalose membrane stabilization macromolecular protectants cell cryopreservation

Effect of the grain boundary character distribution on the sulfur corrosion behaviour and mechanisms of copper windings under different high temperatures

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High Voltage 2024年第3期9卷 566-580页

作者： Xu Dai yuan yuan Jiang Zhou Guoyong Liu Tao Zhu Huiying Xiang Qi Yu Xue gao Ruijin Liao State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqingChina College of Materials Science and Engineering Chongqing UniversityChongqingChina Dongfang Electric Machinery Co. LtdDeyangChina

As a typical failure phenomenon in transformers,sulfur corrosion has garnered significant attention in the field of high-voltage *** boundary character distribution(GBCD)copper windings have been introduced to enhance sulfur corrosion resistance by slowing down intergranular *** this study,the sulfur corrosion behaviour and mechanisms of the GBCD copper windings under various temperatures were experi-mentally and theoretically *** show that GBCD can enhance the corrosion resistance of copper in liquid *** the increase in temperatures,the insulating properties of oil and papers in traditional copper windings experience notable degradation,while GBCD copper windings show more stable insulating *** addition,modelling of grain boundary energy indicates that the grain boundary structure of GBCD copper windings has a lower average interface energy of 0.170 eV/Å***-culations of reaction thermodynamics show that GBCD copper windings possess a higher failure temperature(135.2℃)and inhibition degree(activation energy)of the sulfur corrosion(32,557.62 J/mol),revealing the stability and enhanced sulfur corrosion resis-tance at elevated temperatures.

关键词： corrosion grain copper

Design methodology,synthesis,and control strategy of the high-speed planetary rover

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Frontiers of Mechanical Engineering 2024年第2期19卷 59-74页

作者： Renchao LU Haibo gao Zhen LIU Runze yuan Zongquan DENG State Key Laboratory of Robotics and Systems Harbin Institute of TechnologyHarbin 150001China

The planned missions to explore the surfaces of the Moon and Mars require high exploration efficiency,thus imposing new demands on the mobility system of planetary *** this paper,a design method for a high-speed planetary rover(HPR)is proposed,and the representative configurations are modeled and ***,the influence of the planetary surface environment on the design of HPRs is analyzed,and the design factors for HPRs are determined by studying a single-wheel ***,a design methodology for HPRs is *** adaptive suspension mechanisms of a four-wheeled rover are synthesized using the all-wheel-attachment condition and position and orientation characteristics theory,which are expressed in the form of a graph theory for the increase in elastic components and active ***,a dynamic model is built,and a simulation is carried out for the proposed *** validity of the proposed method and rover is verified,thus highlighting their potential application in future planetary exploration.

关键词： design methodology spectrum analysis high-speed planetary rover type synthesis

Rational design of hydroxytricyanopyrrole-based probes with high affinity and rapid visualization for amyloid-β aggregates in vitro and in vivo

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Chinese Chemical Letters 2024年第5期35卷 290-295页

作者： Jiajia Lv Jie gao Hongyu Li Zeli yuan Nan Dong School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China School of Pharmacy Zunyi Medical UniversityZunyi 563003China Guizhou International Scientific and Technological Cooperation Base for Medical Photo-Theranostics Technology and Innovative Drug Development Zunyi 563003China

As key biomarkers,amyloid-β(Aβ)plaques are frequently used to diagnose Alzheimer’s disease(AD).Although fluorescence imaging has proven to be effective in detecting these plaques,the gold standard probe thioflavin T(ThT),used for Aβaggregates,cannot be applied in vivo owing to its invasive ***,the development of novel fluorescent probes capable of identifying Aβplaques in situ is *** on the ThT structure,twoπ-conjugated heterocyclic D-π-A probes were designed bearing the hydroxytricyanopyrrole acceptor and N,N-dimethylaminophenyl *** probes exhibited red to near-infrared fluorescence emission(λ_(max)=732 nm),large Stokes shifts(>100 nm),exceptional signal-to-noise ratio,rapid response(<30 s),and high binding affinity(NT-HTCP=33.32 nmol/L;NF-HTCP=53.35 nmol/L)for Aβ*** the best candidate,NT-HTCP was used for in situ imaging of Aβplaques in AD mouse ***,in vivo research demonstrated that NT-HTCP could cross the blood-brain barrier and continue imaging the Aβplaques with a good signal-to-noise ***,the outcomes of the docking computations helped guide the development of the Aβ*** study expands the family of N,N-dimethylaminophenyl-based Aβ-sensitive fluorophores,with NTHTCP emerging as a highly promising imaging agent.

关键词： Amyloid-β Fluorescent probe Hydroxytricyanopyrrole Fluorescence imaging Alzheimer’s disease

Mass transfer characteristics of chiral pharmaceuticals on membrane used for polar organic chemical integrative sampler

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Journal of Environmental Sciences 2024年第2期136卷 670-681页

作者： Liyang Wang Ruixia Liu Youya Zhou Peng yuan Xiaoling Liu Hongjie gao College of Water Science Beijing Normal UniversityBeijing 100018China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental ScienceBeijing 100012China Technical Centre for Soil Agriculture and Rural Ecology and EnvironmentMinistry of Ecology and EnvironmentBeijing 100012China

Passive sampling technology has good application prospects for monitoring trace pollutants in aquatic *** research on the sampling mechanism of this technology is essential to improve the measurement accuracy and extend the application scope of this *** this study,adsorption and permeation experiments were performed to investigate the sorption and mass transfer properties of five chiral pharmaceuticals at the enantiomeric level on polyethersulfone(PES)and polytetrafluoroethylene(PTFE)membranes used in a polar organic chemical integrative *** adsorption experiments showed that the PES membrane had an adsorption phenomenon for most selected pollutants and an insignificant sorption behavior was observed for all selected pharmaceuticals on the PTFE membrane except for R(S)-*** diffusion coefficients of selected pharmaceuticals onto the PTFE membrane were approximately one order of magnitude higher than those onto the PES *** permeation experiment indicated that under different hydraulic conditions,the change of the relative pollutant concentration through the PTFE membrane for the composite pollutant system was more obvious than that for the single pollutant system,and mass transfer hysteresis exists for both contaminant systems through PES *** the first-order equation or 3-component model to estimate the overall mass transfer coefficients,the results showed that the overall mass transfer coefficient values of pollutants in the composite pollutant system onto both membranes were higher than those in the single pollutant *** parameter was mainly influenced by the synergistic effects of the multi-analyte interaction and diminished water boundary layers during the mass transfer process.

关键词： Sorption phenomenon Permeation behavior Mass transfer properties Modeling calculation Chiral pharmaceuticals PES and PTFE membrane

Precise regulation of the phase transformation for pyrolusite during the reduction roasting process

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 81-90页

作者： Ruofeng Wang Peng gao Shuai yuan Yanjun Li Yingzhi Liu Cheng Huang School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China National-Local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang 110819China

The mechanism involved in the phase transformation process of pyrolusite (MnO_(2)) during roasting in a reducing atmosphere was systematically elucidated in this study,with the aim of effectively using low-grade complex manganese ore *** to single-factor experiment results,the roasted product with a divalent manganese (Mn^(2+)) distribution rate of 95.30% was obtained at a roasting time of 25 min,a roasting temperature of 700℃,a CO concentration of 20at%,and a total gas volume of 500 mL·min^(-1),in which the manganese was mainly in the form of manganosite (MnO).Scanning electron microscopy and Brunauer–Emmett–Teller theory demonstrated the microstructural evolution of the roasted product and the gradual reduction in the pyrolusite ore from the surface to the core Thermodynamic calculations,X-ray photoelectron spectroscopy,and X-ray diffractometry analyses determined that the phase transformation of pyrolusite followed the order of MnO_(2)→Mn_(2)O_(3)→Mn_(3)O_(4)→MnO phase by phase,and the reduction of manganese oxides in each valence state proceeded simultaneously.

关键词： pyrolusite phase transformation reduction roasting microstructural evolution reaction mechanism

Dual-curvilinear beam enabled tunable manipulation of high-and low-refractive-index particles

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Photonics Research 2024年第7期12卷 1427-1436页

作者： ZHENG yuan CHENCHEN ZHANG yuan gao WENXIANG YAN XIAN LONG ZHI-CHENG REN XI-LIN WANG JIANPING DING HUI-TIAN WANG National Laboratory of Solid State Microstructures and School of Physics Nanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China Collaborative Innovation Center of Solid-State Lighting and Energy-Saving Electronics Nanjing 210093China

We present an innovative approach for the simultaneous agile manipulation of high-refractive-index(HRI) and low-refractive-index(LRI) particles. Our method involves introducing a dual-curvilinear optical vortex beam(DC-OVB) generated by superimposing a pair of curved beams: HRI and LRI particles are controlled by the bright curve and the dark channel between the two curves, respectively. The proposed DC-OVB provides customizable motion paths and velocities for both LRI and HRI particles. Each curve of the DC-OVB can support a distinct orbital flow density(OFD), enabling the application of torques to HRI and LRI particles, guiding them to orbit along specified trajectories and prompting them to execute various curvilinear motions simultaneously,including curvilinear movement, revolution, and rotation.

关键词： tunable refractive beam

Identification of pathological characteristics in pulmonary tuberculosis using polarization-sensitive optical coherence tomography

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Journal of Innovative Optical Health Sciences 2024年第6期17卷 97-106页

作者： Yun Ding Zhuoqun yuan Xiaojiang Zhao Guozheng gao Xin Li Yanmei Liang Clinical School of Thoracic Tianjin Medical University TianjinP.R.China Department of Thoracic Surgery Fujian Provincial Hospital FujianP.R.China Institute of Modern Optics Nankai University Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology Tianjin 300350P.R.China School of Medicine Tianjin University TianjinP.R.China Department of Pathology Tianjin Chest Hospital No.261Taierzhuang South Road Jinnan District Tianjin 300222P.R.China Department of Thoracic Surgery Tianjin Chest Hospital TianjinP.R.China

The low detection rate of Mycobacterium tuberculosis in clinical practice leads to a high rate of missed diagnosis for pulmonary tuberculosis(PTB).As a noninvasive,high-resolution,real-time imaging technology,polarization-sensitive optical coherence tomography(PS-OCT)may be feasible for the rapid identification of pathological *** study aimed to explore the feasibility of using PS-OCT to identify pathological features of *** the experiments,PTB samples containing some surrounding lung tissues were imaged using *** is demonstrated that PS-OCT images showed good consistency with the corresponding pathological images and were able to identify PTB-related characteristic pathological *** think PS-OCT can serve as an effective supplement for the diagnosis of PTB,enabling rapid and accurate diagnosis,and aiding in the understanding of the pathological characteristics and pathophysiological processes of PTB.

关键词： Pulmonary tuberculosis PS-OCT pathological features.