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Chinese Physics B 2024年第9期33卷 576-580页

作者： Xing-feng Zhang Li-bin liu Yu-Qing Li Dong-Tao Zhang Wei-Qiang liu Ming Yue College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

The Sm–Zr–Fe–Co–Ti quinary-alloys with ThMn12 structure has attracted wide attention for ultra-high intrinsic magnetic properties,showing potentiality to be developed into rare-earth permanent *** Ti element in alloys is crucial for phase stability and magnetic properties,and lower Ti content can increase intrinsic magnetic properties but reduce phase *** this study,the 1:12 single-phase melt-spun ribbons with low Ti content was successfully prepared using a rapid solidification non-equilibrium method for the Sm1.1Zr_(0.2)Fe_(9.2)Co_(2.3)Ti_(0.5) ***,this non-equilibrium ribbon did not achieve good magnetic hardening due to the uneven microstructure and ***,annealing was carried out to eliminate micro-strain and homogenize microstructure,therefore,remanence and coercivity were significantly improved even the precipitation of a small amount of a-Fe phase which were not conducive to *** remanence of 86.1 emu/g and coercivity of 151 kA/m was achieved when annealing at 850℃ for 45 *** hot pressing,under the action of high temperature and pressure,a small portion of ThMn12 phases in the magnet decompose into Sm-rich phases and a-Fe,while remanence of 4.02 kGs(1 Gs=10^(-4) T),and coercivity of 1.12 kOe(1 Oe=79.5775 A·m^(-1))were still *** findings can provide reference for exploring practical permanent magnets made of 1:12 type quinary-alloys.

关键词： magnetic materials (Sm,Zr)(Fe,Co,Ti)_(12) magnets nanocrystalline magnet microstructure

Asymmetric Partial Hydrosilylation of 2,2-Difluoro-1,3-diketones with Chiral Frustrated Lewis Pairs

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Chinese Journal of Chemistry 2024年第8期42卷 853-857页

作者： Ting liu Xiangqing feng Haifeng Du Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190 China University of Chinese Academy of Sciences Beijing100049 China

Comprehensive Summary,The asymmetric partial reduction of 1,3-diketones stands as a straightforward pathway to access optically active β-hydroxyketones. In this paper, an asymmetric Piers-type hydrosilylation of 2,2-difluoro-1,3-diketones was successfully realized by using a frustrated Lewis pair of chiral borane and tricyclohexylphosphine as a catalyst, delivering a variety of α,α-difluoro-β-hydroxyketones in high yields with up to 99% ee. Significantly, no over-reduced diol products were observed even with an excess amount of silanes. The product can be conveniently converted to α,α-difluoro-β-hydroxyester or 1,3-anti-diol via an oxidation with m-CPBA or a reduction with DIBAL-H without obvious loss of ee.

关键词： Asymmetric catalysis Hydrosilylation Ketones Frustrated Lewis pairs Chiral boranes

A Random Fusion of Mix 3D and Polar Mix to Improve Semantic Segmentation Performance in 3D Lidar Point Cloud

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 845-862页

作者： Bo liu Li feng Yufeng Chen School of Computer Science and Engineering Macao University of Science and TechnologyMacao999078China School of Computer Science and Artificial Intelligence Chaohu UniversityChaohu238000China Institute of Vehicle Information Control and Network Technology Hubei University of Automotive TechnologyShiyan442002China

This paper focuses on the effective utilization of data augmentation techniques for 3Dlidar point clouds to enhance the performance of neural network *** point clouds,which represent spatial information through a collection of 3D coordinates,have found wide-ranging *** augmentation has emerged as a potent solution to the challenges posed by limited labeled data and the need to enhance model generalization *** of the existing research is devoted to crafting novel data augmentation methods specifically for 3D lidar point ***,there has been a lack of focus on making the most of the numerous existing augmentation *** this deficiency,this research investigates the possibility of combining two fundamental data augmentation *** paper introduces PolarMix andMix3D,two commonly employed augmentation techniques,and presents a new approach,named *** of using a fixed or predetermined combination of augmentation methods,RandomFusion randomly chooses one method from a pool of options for each instance or *** innovative data augmentation technique randomly augments each point in the point cloud with either PolarMix or *** crux of this strategy is the random choice between PolarMix and Mix3Dfor the augmentation of each point within the point cloud data *** results of the experiments conducted validate the efficacy of the RandomFusion strategy in enhancing the performance of neural network models for 3D lidar point cloud semantic segmentation *** is achieved without compromising computational *** examining the potential of merging different augmentation techniques,the research contributes significantly to a more comprehensive understanding of how to utilize existing augmentation methods for 3D lidar point *** data augmentation technique offers a simple yet effective method to leverage the diversity of augmentation techniques and boost the ro

关键词： 3D lidar point cloud data augmentation RandomFusion semantic segmentation

Construction of Pd-doped RuO_(2) nanosheets for efficient and stable acidic water oxidation

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Green Energy & Environment 2024年第6期9卷 937-948页

作者： Yibo liu Xing Hu Chenxi liu Shan Zhu Kezhu Jiang feng liu Shijian Zheng Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology College of Materials Science and EngineeringHebei University of TechnologyTianjin300401China Yunnan Precious Metals Lab Co. LTDKunming650100China

RuO_(2) has been considered a potential alternative to commercial IrO_(2) for the oxygen evolution reaction(OER)due to its superior intrinsic ***,its inherent structure dissolution in acidic environments restricts its commercial *** this study,we report a novel Pd-doped ruthenium oxide(Pd–RuO_(2))nanosheet catalyst that exhibits improved activity and stability through a synergistic effect of Pd modulation of Ru electronic structure and the two-dimensional *** catalyst exhibits excellent performance,achieving an overpotential of only 204 mVat a current density of 10 mA cm^(-2).Impressively,after undergoing 8000 cycles of cyclic voltammetry testing,the overpotential merely decreased by 5 *** PEM electrolyzer with Pd0.08Ru0.92O_(2) as an anode catalyst survived an almost 130 h operation at 200 mA cm^(-2).To elucidate the underlying mechanisms responsible for the enhanced stability,we conducted an X-ray photoelectron spectroscopy(XPS)analysis,which reveals that the electron transfer from Pd to Ru effectively circumvents the over-oxidation of Ru,thus playing a crucial role in enhancing the catalyst's ***,density functional theory(DFT)calculations provide compelling evidence that the introduction of Pd into RuO_(2) effectively modulates electron correlations and facilitates the electron transfer from Pd to Ru,thereby preventing the overoxidation of ***,the application of the two-dimensional structure effectively inhibited the aggregation and growth of nanoparticles,further bolstering the structural integrity of the catalyst.

关键词： Oxygen evolution reaction Pd-doped ruthenium oxide Two-dimensional structure Electron transfer Stability

Achieving near-infrared-light-mediated switchable friction regulation on MXene-based double network hydrogels

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Friction 2024年第1期12卷 39-51页

作者： Pengxi WU Cheng ZENG Jinglun GUO Guoqiang liu feng ZHOU Weimin liu Center of Advanced Lubrication and Sealing Materials State Key Laboratory of Solidification ProcessingNorthwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

MXene possesses great potential in enriching the functionalities of hydrogels due to its unique metallic conductivity,high aspect ratio,near-infrared light(NIR light)responsiveness,and wide tunability,however,the poor compatibility of MXene with hydrogels limits further *** this work,we report a uniformly dispersed MXene-functionalized poly-N-isopropylacrylamide(PNIPAM)/poly-2-acrylamido-2-methyl-1-propanesulfonic acid(PAMPS)double network hydrogel(M–DN hydrogel)that can achieve switchable friction regulation by using the NIR *** dispersity of MXene in hydrogels was significantly improved by incorporating the chitosan(CS)*** M–DN hydrogel showed much low coefficient of friction(COF)at 25℃ due to the presence of hydration layer on hydrogel *** illuminating with the NIR light,M–DN hydrogel with good photothermal effect rapidly raised the temperature to above the lower critical solution temperature(LCST),which led to an obvious increase of surface COF owing to the destruction of the hydration *** addition,M–DN friction control hydrogel showed good recyclability and controllability by tuning“on-off”of the NIR *** work highlights the construction of functional MXene hydrogels for intelligent lubrication,which provides insight for interface sensing,controlled transmission,and flexible robotic arms.

关键词： MXene dispersion photothermal hydrogel near-infrared(NIR)light friction modulation

Disturbance failure mechanism of highly stressed rock in deep excavation:Current status and prospects

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 611-627页

作者： Tao Wang Weiwei Ye Liyuan liu Kai liu Naisheng Jiang Xianhui feng School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China Department of Engineering Science University of OxfordParks RoadOxford OX13PJUK School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

This article reviews the current status on the dynamic behavior of highly stressed rocks under ***,the experimental apparatus,methods,and theories related to the disturbance dynamics of deep,high-stress rock are reviewed,followed by the introduction of scholars’research on deep rock deformation and failure from an energy ***,with a backdrop of highstress phenomena in deep hard rock,such as rock bursts and core disking,we delve into the current state of research on rock microstructure analysis and residual stresses from the perspective of studying the energy storage mechanisms in ***,the current state of research on the mechanical response and the energy dissipation of highly stressed rock formations is briefly ***,the insufficient aspects in the current research on the disturbance and failure mechanisms in deep,highly stressed rock formations are summarized,and prospects for future research are *** work provides new avenues for the research on the mechanical response and damage-fracture mechanisms of rocks under high-stress conditions.

关键词： deep rock with high stress highly stressed rock rock failure residual stress energy release

Fatigue properties and damage constitutive model of salt rock based on CT scanning

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International Journal of Mining Science and Technology 2024年第2期34卷 245-259页

作者： Junbao Wang Xiao liu Qiang Zhang Xinrong liu Zhanping Song Shijin feng College of Civil Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Shaanxi Key Lab of Geotechnical and Underground Space Engineering Xi’an 710055China School of Civil Engineering Chongqing UniversityChongqing 400045China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

To investigate the macroscopic fatigue properties and the mesoscopic pore evolution characteristics of salt rock under cyclic loading,fatigue tests under different upper-limit stresses were carried out on salt rock,and the mesoscopic pore structures of salt rock before and after fatigue tests and under different cycle numbers were measured using CT scanning *** on the test results,the effects of the cycle number and the upper-limit stress on the evolution of cracks,pore morphology,pore number,pore volume,pore size,plane porosity,and volume porosity of salt rock were *** failure path of salt rock specimens under cyclic loading was analyzed using the distribution law of plane *** damage variable of salt rock under cyclic loading was defined on basis of the variation of volume porosity with cycle *** order to describe the fatigue deformation behavior of salt rock under cyclic loading,the nonlinear Burgers damage constitutive model was further *** results show that the model established can better reflect the whole development process of fatigue deformation of salt rock under cyclic loading.

关键词： Salt rock Cyclic loading CT scanning Mesoscopic pore evolution Constitutive model

Discovery of TK-642 as a highly potent,selective,orally bioavailable pyrazolopyrazine-based allosteric SHP2 inhibitor

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Acta Pharmaceutica Sinica B 2024年第8期14卷 3624-3642页

作者： Kai Tang Shu Wang Siqi feng Xinyu Yang Yueyang Guo Xiangli Ren Linyue Bai bin Yu Hong-Min liu Yihui Song School of Pharmaceutical Sciences&Key Laboratory of Advanced Drug Preparation Technologies Ministry of EducationZhengzhou UniversityZhengzhou 450001China College of Chemistry Pingyuan LaboratoryState Key Laboratory of Antiviral DrugsZhengzhou UniversityZhengzhou 450001China Tianjian Laboratory of Advanced Biomedical Sciences Institute of Advanced Biomedical SciencesZhengzhou UniversityZhengzhou 450000China State Key Laboratory of Pharmaceutical Biotechnology Nanjing UniversityNanjing 210023China

Src homology-2-containing protein tyrosine phosphatase 2(SHP2)is a promising therapeutic target for cancer *** this work,we presented the structure-guided design of 5,6-fused bicyclic allosteric SHP2 inhibitors,leading to the identification of pyrazolopyrazine-based TK-642 as a highly potent,selective,orally bioavailable allosteric SHP2 inhibitor(SHP2WT IC_(50)=2.7 nmol/L)with favorable pharmacokinetic profiles(F=42.5%;t_(1/2)=2.47 h).Both dual inhibition biochemical assay and docking analysis indicated that TK-642 likely bound to the“tunnel”allosteric site of ***-642 could effectively suppress cell proliferation(KYSE-520 cells IC_(50)=5.73μmol/L)and induce apoptosis in esophageal cancer cells by targeting the SHP2-mediated AKT and ERK signaling ***,oral administration of TK-642 also demonstrated effective anti-tumor effects in the KYSE-520 xenograft mouse model,with a T/C value of 83.69%.Collectively,TK-642 may warrant further investigation as a promising lead compound for the treatment of esophageal cancer.

关键词： Protein tyrosine phosphatase Pyrazolopyrazine SHP2 inhibitor Esophageal cancer

Constructal design of a rectangular porous fin considering minimization of maximum temperature difference and pumping power consumption

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Science China(Technological Sciences) 2024年第3期67卷 919-929页

作者： liu XiaoYe feng HuiJun CHEN LinGen GE YanLin Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China College of Power Engineering Naval University of EngineeringWuhan 430033China Hubei Provincial Engineering Technology Research Center of Green Chemical Equipment Wuhan 430205China School of Mechanical&Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China

A heat dissipation model of a rectangular porous fin is established based on constructal theory. First, the constructal design of rectangular porous fin is conducted by selecting a complex function minimization, which composed of linear weighting sum of maximum temperature difference and pumping power consumption, as optimization objective. Effects of gap height, air inlet velocity, total porous fin volume and porosity on the optimal constructs are investigated, respectively. The findings show that the complex function can attain its double minimum at a value of 0.802 when the fin length and number are optimized, and the corresponding optimal fin length and number are 8.01 mm and 10, respectively. In comparison to original design, the complex function and maximum temperature difference after twice optimization are decreased by 19.80% and 66.31%, ***, the comprehensive performance of porous fin is improved by simultaneously optimizing the fin length and number. The artificial neural network is applied to predict the fin performances, which is used to conduct multi-objective optimization based on NSGA-II algorithm. Optimal structure of porous fin for multiple requirements is gained by LINMAP and TOPSIS decisionmaking strategies. The findings in this study can serve as theoretical guides for fin thermal designs of electronic devices.

关键词： constructal theory rectangular porous fin pumping power consumption maximum temperature difference complex function multi-objective optimization

Exploring cerebral structural and functional abnormalities in a mouse model of post-traumatic headache induced by mild traumatic brain injury

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Zoological Research 2024年第3期45卷 648-662页

作者： Dan Yang bin-bin Nie Jin-Gang He Zong-Qiang Lv feng-feng Mo Si-Yi Ouyang Jie Wang Ju-Xiang Chen Tao Tao Department of Anesthesiology Central People’s Hospital of ZhanjiangZhanjiangGuangdong 524045China Key Laboratory of Nuclear Radiation and Nuclear Energy Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Key Laboratory of Magnetic Resonance in Biological Systems State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsNational Center for Magnetic Resonance in WuhanWuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences-Wuhan National Laboratory for OptoelectronicsWuhanHubei 430071China Department of Neurosurgery Changhai HospitalNaval Medical UniversityShanghai 200082China Department of Nutrition and Food Hygiene Faculty of Naval MedicineNaval Medical UniversityShanghai 200433China Department of Anesthesiology Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515China Institute of Neuroscience and Brain Diseases/Xiangyang Central Hospital Affiliated Hospital of Hubei University of Arts and ScienceXiangyangHubei 441021China Songjiang Hospital and Songjiang Research Institute Shanghai Jiao Tong University School of MedicineShanghai 201600China Department of Anesthesiology Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515China

Mild traumatic brain injury(mTBI)-induced post-traumatic headache(PTH)is a pressing public health concern and leading cause of disability *** PTH is often accompanied by neurological disorders,the exact underlying mechanism remains largely *** potential biomarkers may prompt the diagnosis and development of effective treatments for mTBI-induced *** this study,a mouse model of mTBI-induced PTH was established to investigate its effects on cerebral structure and function during short-term *** indicated that mice with mTBI-induced PTH exhibited balance deficits during the early post-injury *** kinetics revealed that variations in neurotransmitters were most prominent in the cerebellum,temporal lobe/cortex,and hippocampal regions during the early stages of ***,variations in brain functional activities and connectivity were further detected in the early stage of PTH,particularly in the cerebellum and temporal cortex,suggesting that these regions play central roles in the mechanism underlying ***,our results suggested that GABA and glutamate may serve as potential diagnostic or prognostic biomarkers for *** studies should explore the specific neural circuits involved in the regulation of PTH by the cerebellum and temporal cortex,with these two regions potentially utilized as targets for non-invasive stimulation in future clinical treatment.

关键词： Post-traumatic headache(PTH) Mild traumatic brain injury(mTBI) Metabolic kinetics fMRI Cerebellum