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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 Nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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Predictive model based on magnetic resonance imaging for chemotherapy response in colorectal cancer:Toward a radiologic biopsy approach
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作者 Ilya D Klabukov Anna Smirnova +2 位作者 Irina Kondrasheva Denis S Baranovskii Elena Yatsenko 《World Journal of Gastrointestinal Oncology》 2026年第1期296-299,共4页
We read with great interest the investigation of Kang et al related the applications of the multiparametric magnetic resonance imaging-based predictive model for assessing chemotherapy efficacy in colorectal cancer pa... We read with great interest the investigation of Kang et al related the applications of the multiparametric magnetic resonance imaging-based predictive model for assessing chemotherapy efficacy in colorectal cancer patients with gene mutations.The authors focused on decision-making based on the integration of tumor differentiation,signal intensity ratio,margin distance,and magnetic resonance imaging-detected lymph node metastasis.Indeed,these multiparameter predictive models could also be used for diagnosis as an alternative to invasive tissue examination methods.However,progress in this field enables us to shift the paradigm to radiology biopsies,particularly given the nonlinear effects of various radiation sources. 展开更多
关键词 BIOPSY Cancer Extracellular matrix ONCOLOGY RADIOLOGY Tumor microenvironment TUMORIGENESIS
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Cancer cell-dependent increase in senescence-like populationsfollowing exosome treatment:The role of extracellular matrix andcellular glycocalyx
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作者 Ilya D Klabukov Anastas Kisel +2 位作者 Elena Yatsenko Yana Sulina Denis S Baranovskii 《World Journal of Stem Cells》 2026年第1期108-111,共4页
We read with the great interest the study by Ababneh et al in which inducedmesenchymal stem cell-derived exosomes were shown to exhibit a stronger andmore sustained anti-proliferative effect by inducing a senescence-l... We read with the great interest the study by Ababneh et al in which inducedmesenchymal stem cell-derived exosomes were shown to exhibit a stronger andmore sustained anti-proliferative effect by inducing a senescence-like state withoutapoptosis.The results obtained by the authors highlight the features of theeffects of senescent drift induction in surrounding tissues.In the light of thesefindings,the role of the properties of extracellular matrix and cellular glycocalyxin responses of human tumors to therapy remain uninvestigated.These extracellularbarriers appear to be significant obstacles to effective cancer therapy,especiallyin relation to the use of unique properties of tumor microenvironment forthe immunotherapy-resistant cancer treatment. 展开更多
关键词 Cancer Extracellular matrix GLYCOCALYX EXOSOMES Extracellular vesicles Tumor microenvironment
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Porcine decellularized nerve matrix hydrogel attenuates neuroinflammation after peripheral nerve injury by inhibiting the TLR4/MyD88/NF-κB axis
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作者 Rui Li Jianquan Liu +7 位作者 Liuxun Li Guotian Luo Xinrong Yuan Shichao Shen Yongpeng Shi Jianlong Wu Bin Yan Lei Yang 《Neural Regeneration Research》 2026年第3期1222-1235,共14页
Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological prop... Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological properties and tissue specificity,highlighting its potential as a biomedical material for the repair of severe peripheral nerve injury;however,its role in modulating neuroinflammation post-peripheral nerve injury remains unknown.Here,we aimed to characterize the anti-inflammatory properties of porcine decellularized nerve matrix hydrogel and their underlying molecular mechanisms.Using peripheral nerve injury model rats treated with porcine decellularized nerve matrix hydrogel,we evaluated structural and functional recovery,macrophage phenotype alteration,specific cytokine expression,and changes in related signaling molecules in vivo.Similar parameters were evaluated in vitro using monocyte/macrophage cell lines stimulated with lipopolysaccharide and cultured on porcine decellularized nerve matrix hydrogel-coated plates in complete medium.These comprehensive analyses revealed that porcine decellularized nerve matrix hydrogel attenuated the activation of excessive inflammation at the early stage of peripheral nerve injury and increased the proportion of the M2 subtype in monocytes/macrophages.Additionally,porcine decellularized nerve matrix hydrogel negatively regulated the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB axis both in vivo and in vitro.Our findings suggest that the efficacious anti-inflammatory properties of porcine decellularized nerve matrix hydrogel induce M2 macrophage polarization via suppression of the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB pathway,providing new insights into the therapeutic mechanism of porcine decellularized nerve matrix hydrogel in peripheral nerve injury. 展开更多
关键词 anti-inflammatory reaction macrophage polarization NEUROINFLAMMATION peripheral nerve injury porcine decellularized nerve matrix hydrogel
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基于Matrix Core的高性能多维FFT设计与优化 被引量:1
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作者 陆璐 祝松祥 +2 位作者 田卿燕 林海山 郭逸劼 《华南理工大学学报(自然科学版)》 北大核心 2025年第3期20-30,共11页
快速傅里叶变换(FFT)算法广泛应用于科学计算等领域。为了充分挖掘图形处理器(GPU)的计算能力并进一步提高FFT的计算效率,该文针对矩阵形式的Stockham FFT,提出了一种基于Matrix Core的高性能多维FFT计算方案。在计算优化方面,该方案利... 快速傅里叶变换(FFT)算法广泛应用于科学计算等领域。为了充分挖掘图形处理器(GPU)的计算能力并进一步提高FFT的计算效率,该文针对矩阵形式的Stockham FFT,提出了一种基于Matrix Core的高性能多维FFT计算方案。在计算优化方面,该方案利用Matrix Core加速FFT计算中的矩阵乘运算,同时通过编译器内部指令完成小粒度的矩阵乘加,使得Matrix Core支持更多尺寸的FFT计算。在内存优化方面,该方案使用2层迭代策略,以充分利用共享内存,减少与全局内存的数据交换;根据Matrix Core的矩阵数据在各个线程寄存器中的分布规律,直接在寄存器上完成FFT计算中大量存在的矩阵逐元素乘操作;通过对共享内存中的数据进行重排来缓解存储体冲突,并采用双缓冲策略缓解访存瓶颈。该文还提出了高效的矩阵转置策略,以加速多维FFT计算。在AMD MI250 GPU平台上将该方案与GPU上主流的高性能FFT计算库rocFFT和VkFFT进行了比较实验,结果表明:该方案在AMD MI250上的1维、2维和3维FFT平均计算效率均优于rocFFT和VkFFT,3维FFT的平均计算效率为rocFFT的1.5倍,为VkFFT的2.0倍,具有较好的性能提升;mcFFT的计算精度与rocFFT和VkFFT保持在相同水平。 展开更多
关键词 图形处理器 Matrix Core 快速傅里叶变换 矩阵乘法
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基于Matrix Core的小尺寸批量矩阵乘法设计与优化
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作者 陆璐 赵容 +1 位作者 梁志宏 索思亮 《华南理工大学学报(自然科学版)》 北大核心 2025年第9期48-58,共11页
通用矩阵乘法(GEMM)是线性代数中最重要的运算,来自不同科学领域的许多应用程序都将其关键部分转换为使用GEMM的形式。GEMM广泛应用于大模型、机器学习、科学计算和信号处理等领域。特别是半精度的批处理GEMM(即FP16)一直是许多深度学... 通用矩阵乘法(GEMM)是线性代数中最重要的运算,来自不同科学领域的许多应用程序都将其关键部分转换为使用GEMM的形式。GEMM广泛应用于大模型、机器学习、科学计算和信号处理等领域。特别是半精度的批处理GEMM(即FP16)一直是许多深度学习框架的核心操作。目前AMD GPU上半精度批处理GEMM的访存和计算利用率不足,急需优化。为此,该文提出了一种半精度批处理GEMM(HGEMM)的图形处理器(GPU)优化方案。分块策略方面,根据输入矩阵块大小为线程分配相同的访存量和计算量,同时线程计算多个矩阵乘法,以提高计算单元的利用率。访存优化方面,以多读数据为代价,为每个线程分配相同访存量以便于编译器优化,保证访存和计算时间相互掩盖。对于矩阵尺寸小于16的极小尺寸批处理HGEMM,该文利用4×4×4的Matrix Core及其对应的分块方案,在提升访存性能的同时减少Matrix Core计算资源的浪费,并提供是否使用共享内存的选项来达到最高性能。在AMD GPU MI210平台上,将该方案与rocBLAS的2个算子进行性能对比,结果表明:该方案在AMD GPU MI210上的平均性能为rocBLASHGEMMBatched的4.14倍,rocBLASGEMMExBatched的4.96倍;对于极小尺寸批处理HGEMM,平均性能为rocBLASHGEMMBatched的18.60倍,rocBLASGEMMExBatched的14.02倍。 展开更多
关键词 图形处理器 Matrix Core 矩阵乘法 访存优化
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Preparation of zinc sulfate open frameworks based probe materials and detection of Pb^(2+)and Fe^(3+)ions 被引量:1
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作者 LU Pingping ZHANG Shuguang +1 位作者 ZHANG Peipei NI Aiyun 《无机化学学报》 北大核心 2025年第5期959-968,共10页
A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phospho... A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phosphorescence(RTP)properties,was prepared by doping 2,6-naphthalic acid(P)into matrix1at a low con-centration.P@1emitted a green RTP that was visible to the naked eye and lasted for approximately 2 s.P@1exhib-ited selective phosphorescence enhancement response towards Pb^(2+),with a detection limit of 2.52μmol·L^(-1).Themain detection mechanism is the Pb—O coordination-induced phosphorescence enhancement in the system.Inter-estingly,P@1also functioned as a dual-channel probe for the rapid detection of Fe^(3+)ions through fluorescencequenching with a detection limit of 0.038μmol·L^(-1).The recognition mechanism may be attributed to the competi-tive energy absorption betweenP@1and Fe^(3+)ions.CCDC:2388502,1. 展开更多
关键词 zinc sulfate matrix DOPING phosphorescence and fluorescence probes Pb^(2+) Fe^(3+)
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Immunohistochemical expression of matrix metalloproteinase-9 and 13 in oral squamous cell carcinoma and their role in predicting lymph node metastasis 被引量:1
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作者 Bhari Sharanesha Manjunatha Keshav T Handge +2 位作者 Vandana Sandeep Shah Yasser Eid Al-Thobaiti Deepak Gowda Sadashivappa Pateel 《World Journal of Methodology》 2025年第2期108-116,共9页
BACKGROUND One of the main characteristics of oral squamous cell carcinoma(OSCC)is that it metastasizes to cervical lymph nodes frequently with a high degree of local invasiveness.A primary feature of malignant tumors... BACKGROUND One of the main characteristics of oral squamous cell carcinoma(OSCC)is that it metastasizes to cervical lymph nodes frequently with a high degree of local invasiveness.A primary feature of malignant tumors is their penetration of neighboring tissues,such as lymphatic and blood arteries,due to the tumor cells'capacity to break down the extracellular matrix(ECM).Matrix metalloproteinases(MMPs)constitute a family of proteolytic enzymes that facilitate tissue remodeling and the degradation of the ECM.MMP-9 and MMP-13 belong to the group of extracellular matrix degrading enzymes and their expression has been studied in OSCC because of their specific functions.MMP-13,a collagenase family member,is thought to play an essential role in the MMP activation cascade by breaking down the fibrillar collagens,whereas MMP-9 is thought to accelerate the growth of tumors.Elevated MMP-13 expression has been associated with tumor behavior and patient prognosis in a number of malignant cases.AIM To assess the immunohistochemical expression of MMP-9 and MMP-13 in OSCC.METHODS A total of 40 cases with histologically confirmed OSCC by incisional biopsy were included in this cross-sectional retrospective study.The protocols for both MMP-9 and MMP-13 immunohistochemical staining were performed according to the manufacturer’s recommendations along with the normal gingival epithelium as a positive control.All the observations were recorded and Pearson’sχ²test with Fisher exact test was used for statistical analysis.RESULTS Our study showed no significant correlation between MMP-9 and MMP-13 staining intensity and tumor size.The majority of the patients were in advanced TNM stages(III and IV),and showed intense expression of MMP-9 and MMP-13.CONCLUSION The present study suggests that both MMP-9 and MMP-13 play an important and independent role in OSCC progression and invasiveness.Intense expression of MMP-9 and MMP-13,irrespective of histological grade of OSCC,correlates well with TNM stage.Consequently,it is evident that MMP-9 and MMP-13 are important for the invasiveness and progression of tumors.The findings may facilitate the development of new approaches for evaluating lymph node metastases and interventional therapy techniques,hence enhancing the prognosis of patients diagnosed with OSCC. 展开更多
关键词 Matrix metalloproteinases Oral squamous cell carcinoma Tumor staging IMMUNOHISTOCHEMISTRY INVASION Lymph node metastasis TNM stage
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Femtosecond laser rotary drilling for SiC_(f)/SiC composites 被引量:3
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作者 Feng YANG Zhigang DONG +3 位作者 Renke KANG Hongbin MA Guangyi MA Yan BAO 《Chinese Journal of Aeronautics》 2025年第2期478-490,共13页
SiC_(f)/SiC ceramic matrix composites(SiC_(f)/SiC composites)are difficult to drill small holes due to their heterogeneity,high hardness,and low electrical conductivity.In order to solve the difficulties of poor quali... SiC_(f)/SiC ceramic matrix composites(SiC_(f)/SiC composites)are difficult to drill small holes due to their heterogeneity,high hardness,and low electrical conductivity.In order to solve the difficulties of poor quality and low efficiency when drilling small holes,a novel femtosecond laser rotary drilling(FLRD)technique is proposed.Beam kinematic paths and experimental studies were carried out to analyze the effects of processing parameters on the drilling results in the two-step drilling process.In the through-hole drilling stage,the material removal rate increases with increasing laser power,decreasing feed speed and decreasing pitch.As for the finishing stage of drilling,the exit diameter increased with increasing laser power and decreasing feed speed.The drilling parameters were selected by taking the processing efficiency of through-hole and the quality of finished hole as the constraint criteria.Holes with a diameter of 500μm were drilled using FLRD in 3 mm thick SiC_(f)/SiC composites with a drilling time<150 s.The hole aspect ratio was 6,the taper<0.2°,and there was no significant thermal damage at the orifice or the wall of the hole.The FLRD provides a solution for precision machining of small holes in difficult-to-machine materials by offering the advantages of high processing quality and short drilling times. 展开更多
关键词 Ceramic matrix composites Femtosecond lasers DRILLING HIGH-QUALITY Film cooling holes
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Characterization and source apportionment of volatile organic compounds in Hong Kong:A 5-year study for three different archetypical sites 被引量:2
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作者 Yuchen Mai Vincent Cheung +5 位作者 Peter K.K.Louie Kenneth Leung Jimmy C.H.Fung Alexis K.H.Lau Donald R.B.lake Dasa Gu 《Journal of Environmental Sciences》 2025年第5期424-440,共17页
Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ... Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ozone pollution as its major precursors.This study analyzed VOC characteristics of roadside,suburban,and rural sites in Hong Kong to investigate their compositions,concentrations,and source contributions.Herewe showthat the TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,respectively.By using Positive Matrix Factorization(PMF)model,six sources were identified at the roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguished at the suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and LPG usage were the primary contributors to OFP and OH reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OFP and OH reactivity at the suburban and rural sites,respectively.These findings highlight the importance of identifying and characterizing VOC sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas. 展开更多
关键词 Volatile organic compounds Positive matrix factorization Source apportionment Ozone formation
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Extracellular matrix gene set and microRNA network in intestinal ischemia-reperfusion injury:Insights from RNA sequencing for diagnosis and therapy 被引量:1
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作者 Dao-Jian Xu Guo-Tao Wang Qiang Zhong 《World Journal of Gastrointestinal Surgery》 2025年第2期25-36,共12页
Intestinal ischemia-reperfusion injury(IIRI)is a complex and severe pathophysiological process characterized by oxidative stress,inflammation,and apoptosis.In recent years,the critical roles of extracellular matrix(EC... Intestinal ischemia-reperfusion injury(IIRI)is a complex and severe pathophysiological process characterized by oxidative stress,inflammation,and apoptosis.In recent years,the critical roles of extracellular matrix(ECM)genes and microRNAs(miRNAs)in IIRI have garnered widespread attention.This review aims to systematically summarize the diagnostic and therapeutic potential of ECM gene sets and miRNA regulatory networks in IIRI.First,we review the molecular mechanisms of IIRI,focusing on the dual role of the ECM in tissue injury and repair processes.The expression changes and functions of ECM components such as collagen,elastin,and matrix metalloproteinases during IIRI progression are deeply analyzed.Second,we systematically summarize the regulatory roles of miRNAs in IIRI,particularly the mechanisms and functions of miRNAs such as miR-125b and miR-200a in regulating inflammation,apoptosis,and ECM remodeling.Additionally,this review discusses potential diagnostic biomarkers and treatment strategies based on ECM genes and miRNAs.We extensively evaluate the prospects of miRNA-targeted therapy and ECM component modulation in preventing and treating IIRI,emphasizing the clinical translational potential of these emerging therapies.In conclusion,the diagnostic and therapeutic potential of ECM gene sets and miRNA regulatory networks in IIRI provides new directions for further research,necessitating additional clinical and basic studies to validate and expand these findings for improving clinical outcomes in IIRI patients. 展开更多
关键词 Diagnostic biomarkers Extracellular matrix Gene expression Intestinal ischemia-reperfusion injury Matrix metalloproteinases MICRORNA Treatment strategies
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Matrix stiffness regulates nucleus pulposus cell glycolysis by MRTF-A-dependent mechanotransduction 被引量:1
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作者 Haoran Xu Kang Wei +10 位作者 Jinhao Ni Xiaofeng Deng Yuexing Wang Taiyang Xiang Fanglong Song Qianliang Wang Yanping Niu Fengxian Jiang Jun Wang Lei Sheng Jun Dai 《Bone Research》 2025年第2期476-489,共14页
Increased matrix stiffness of nucleus pulposus(NP)tissue is a main feature of intervertebral disc degeneration(IVDD)and affects various functions of nucleus pulposus cells(NPCs).Glycolysis is the main energy source fo... Increased matrix stiffness of nucleus pulposus(NP)tissue is a main feature of intervertebral disc degeneration(IVDD)and affects various functions of nucleus pulposus cells(NPCs).Glycolysis is the main energy source for NPC survival,but the effects and underlying mechanisms of increased extracellular matrix(ECM)stiffness on NPC glycolysis remain unknown.In this study,hydrogels with different stiffness were established to mimic the mechanical environment of NPCs.Notably,increased matrix stiffness in degenerated NP tissues from IVDD patients was accompanied with impaired glycolysis,and NPCs cultured on rigid substrates exhibited a reduction in glycolysis. 展开更多
关键词 MECHANOTRANSDUCTION nucleus pulposus cells npcs glycolysis increased matrix stiffness nucleus pulposus np tissue nucleus pulposus cells matrix stiffness intervertebral disc degeneration ivdd GLYCOLYSIS
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Charge carrier management via semiconducting matrix for efficient self-powered quantum dot infrared photodetectors 被引量:1
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作者 Jianfeng Ding Xinying Liu +3 位作者 Yueyue Gao Chen Dong Gentian Yue Furui Tan 《Journal of Semiconductors》 2025年第3期74-81,共8页
Quantum dot(QD)-based infrared photodetector is a promising technology that can implement current monitoring,imaging and optical communication in the infrared region. However, the photodetection performance of self-po... Quantum dot(QD)-based infrared photodetector is a promising technology that can implement current monitoring,imaging and optical communication in the infrared region. However, the photodetection performance of self-powered QD devices is still limited by their unfavorable charge carrier dynamics due to their intrinsically discrete charge carrier transport process. Herein, we strategically constructed semiconducting matrix in QD film to achieve efficient charge transfer and extraction.The p-type semiconducting CuSCN was selected as energy-aligned matrix to match the n-type colloidal PbS QDs that was used as proof-of-concept. Note that the PbS QD/CuSCN matrix not only enables efficient charge carrier separation and transfer at nano-interfaces but also provides continuous charge carrier transport pathways that are different from the hoping process in neat QD film, resulting in improved charge mobility and derived collection efficiency. As a result, the target structure delivers high specific detectivity of 4.38 × 10^(12)Jones and responsivity of 782 mA/W at 808 nm, which is superior than that of the PbS QD-only photodetector(4.66 × 10^(11)Jones and 338 mA/W). This work provides a new structure candidate for efficient colloidal QD based optoelectronic devices. 展开更多
关键词 quantum dot semiconducting matrix ligand exchange self-powered photodetectors
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The growth behavior and performance of microarc oxidation coating on AZ91/Ti composite: Influence of Ti-reinforcement phase and electrolyte 被引量:1
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作者 Jinchao Jiao Yongrui Gu +4 位作者 Jin Zhang Yong Lian Xintao Li Kaihong Zheng Fusheng Pan 《Journal of Magnesium and Alloys》 2025年第3期1160-1175,共16页
Magnesium matrix composites with both high strength and ductility have been achieved by introducing pure Ti particles.However,the properties of the surfaces of the composites need to be improved by surface technology,... Magnesium matrix composites with both high strength and ductility have been achieved by introducing pure Ti particles.However,the properties of the surfaces of the composites need to be improved by surface technology,such as micro-arc oxidation(MAO).In this study,we investigated the influence of the Ti-reinforcement phase on coating growth and evolution by subjecting both AZ91 alloy and AZ91/Ti composite to MAO treatment using silicate-based and phosphate-based electrolytes.Results revealed that the Ti-reinforcement phase influenced the MAO process,altering discharge behavior,and leading to a decreased cell voltage.The vigorous discharge of the Ti-reinforcement phase induced the formation of coating discharge channels,concurrently dissolving and oxidizing Ti-reinforcement to produce a composite ceramic coating with TiO2.The MAO coating on the AZ91/Ti composite exhibited a dark blue macromorphology and distinctive local micromorphological anomalies.In silicate electrolyte,a“volcano-like”localized morphology centered on the discharge channel emerged.In contrast,treatment in phosphate-based electrolyte resulted in a coating morphology similar to typical porous ceramic coatings,with visible radial discharge micropores at the reinforcement phase location.Compared to the AZ91 alloy,the coating on the AZ91/Ti composite exhibited lower thickness and higher porosity.MAO treatment reduced the self-corrosion current density of the AZ91/Ti surface by two orders of magnitude.The silicate coating demonstrated better corrosion resistance than the phosphate coating,attributed to its lower porosity.The formation mechanism of MAO coatings on AZ91/Ti composites in phosphate-based and silicate-based electrolytes was proposed. 展开更多
关键词 Magnesium matrix composites Ti-reinforcement Micro-arc oxidation Growth behavior
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Research progress on anti-aging effects and mechanisms of the new ginsenoside Compound K 被引量:1
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作者 Zhiqin Fang Jingyin Zhang +1 位作者 Jianwen Huang Shuibin Cen 《Journal of Dermatologic Science and Cosmetic Technology》 2025年第1期73-83,共11页
Anti-aging research has become a popular scientific field with the increasing prominence of population aging.Rare ginsenoside Compound K(CK)has attracted widespread attention as an emerging anti-aging active ingredien... Anti-aging research has become a popular scientific field with the increasing prominence of population aging.Rare ginsenoside Compound K(CK)has attracted widespread attention as an emerging anti-aging active ingredient.The anti-aging effect of ginsenosides is considered to be one of the important roles of ginsenosides,and Compound K,as the main deglycosylated metabolite of ginsenosides,has a comprehensive anti-aging effect as a highly active ingredient obtained by transformation under the action of microbiota.Recent studies have shown that ginsenosides have anti-photo-oxidation,anti-skin aging,free radical scavenging and immunostimulatory effects,which can effectively prevent skin photoaging.With the progress of modern natural medicine extraction technology and the deepening of the research on the anti-skin aging of ginsenosides'high active ingredients,it will promote the development and application of natural product protective skin photoaging preparations.The rare ginsenoside Compound K plays an important role in the improvement of skin health and anti-aging,which is mainly realized by increasing the activity of antioxidant enzymes,inducing the expression of related genes,reducing the content of oxidative damage substances,regulating the immune system,and influencing the expression of cell-cycle regulators and aging genes.A more comprehensive and in-depth study of the molecular mechanism of the anti-aging effect of rare ginsenoside Compound K will be one of the focuses of future research. 展开更多
关键词 Ginsenoside Compound K Skin aging PHOTOAGING INFLAMMATION Extracellular matrix Cellular autophagy MITOCHONDRIA Longevity genes
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A novel CoCrNi-based medium-entropy alloy self-lubricating composite with superior wear performance 被引量:1
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作者 Ming-Da Xie Wen-Ting Ye +4 位作者 Qing Zhou Lei Jia Biao Chen Meng-Qian Zhang Hai-Feng Wang 《Rare Metals》 2025年第3期2011-2026,共16页
CoCrNi medium-entropy alloy has demonstrated remarkable mechanical properties,suggesting its potential as a structural material.Nevertheless,the challenge lies in achieving an elusive combination of high hardness and ... CoCrNi medium-entropy alloy has demonstrated remarkable mechanical properties,suggesting its potential as a structural material.Nevertheless,the challenge lies in achieving an elusive combination of high hardness and inherent self-lubrication on the worn surface,which is crucial for attaining exceptional tribological performance in medium-entropy alloy(MEA).This study reports the preparation of a novel CoCrNi-based self-lubricating composite by powder metallurgy,which is reinforced simultaneously with Ag solid lubricating phase and SiC ceramic particles.During the sintering process,SiC decomposes to form high hardness in situ Cr_(23)C_(6),enabling the composite to achieve high load-bearing capacity.During the sliding process,thick and dense Ag self-lubricating film is successfully achieved due to the mechanical and thermal effects.The protective tribo-layer effectively mitigates surface stress concentration induced by wear,thereby inhibiting surface coarsening and substantially enhancing the tribological performance.The results showed that compared with CoCrNi MEA,the wear rate and friction coefficient of CoCrNi/SiC/Ag composite are reduced by 88.1%and 32.8%,respectively,showing superior tribological properties over most MEA-based self-lubrication composites.This study further elucidates the wear mechanism of CoCrNi/SiC/Ag composite,providing a new strategy for developing self-lubricating materials with excellent comprehensive performance,which overcomes the inherent trade-off between wear resistance and lubrication. 展开更多
关键词 SELF-LUBRICATING Medium-entropy alloy matrix composite CoCrNi In situ carbide
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Characteristics and phytotoxicity of hydrochar-derived dissolved organic matter:Effects of feedstock type and hydrothermal temperature 被引量:1
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作者 Qianqian Lang Xuan Guo +8 位作者 Chao Wang Lingyao Li Yufei Li Junxiang Xu Xiang Zhao Jijin Li Bensheng Liu Qinping Sun Guoyuan Zou 《Journal of Environmental Sciences》 2025年第3期139-148,共10页
The dissolved organic matter(DOM)with high mobility and reactivity plays a crucial role in soil.In this study,the characteristics and phytotoxicity ofDOMreleased fromthe hydrochars prepared from different feedstocks(c... The dissolved organic matter(DOM)with high mobility and reactivity plays a crucial role in soil.In this study,the characteristics and phytotoxicity ofDOMreleased fromthe hydrochars prepared from different feedstocks(cowmanure,corn stalk and Myriophyllum aquaticum)under three hydrothermal carbonization(HTC)temperatures(180,200 and 220°C)were evaluated.The results showed that the hydrochars had high dissolved organic carbon content(20.15 to 37.65 mg/g)and its content showed a gradual reduction as HTC temperature increased.Three fluorescent components including mixed substance of fulvic acid-like and humic acid-like substances(C1,30.92%-58.32%),UVA humic acid-like substance(C2,25.27%-29.94%)and protein-like substance(C3,11.74%-41.92%)were identified in hydrochar DOM by excitation emission matrix spectra coupled with parallel factor analysis.High HTC temperature increased the relative proportion of aromatic substances(C1+C2)and humification degree of hydrochar DOM from cow manure,while it presented adverse effects on the hydrochar DOM from corn stalk and Myriophyllum.aquaticum.The principal component analysis suggested that feedstock type and HTC temperature posed significant effects on the characteristics of hydrochar DOM.Additionally,seed germination test of all hydrochar DOM demonstrated that the root length was reduced by 8.88%-26.43%in contrast with control,and the germination index values were 73.57%-91.12%.These findings provided new insights into the potential environmental effects for hydrochar application in soil. 展开更多
关键词 Hydrochar Hydrothermal temperature Dissolved organic matter Excitation emission matrix Parallel factor analysis PHYTOTOXICITY
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Collaborative enhancement of thermal diffusivities and mechanical properties of C_(sf)-Cu/Mg composites via introducing Cu coating with different thicknesses 被引量:1
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作者 Yuan Ma Lingjun Guo +3 位作者 Jiancheng Wang Baolin Chen Lehua Qi Hejun Li 《Journal of Magnesium and Alloys》 2025年第1期229-242,共14页
Mg alloy matrix composites reinforced with short carbon fibers(C_(sf)/Mg)are considered as potential candidates for integrated structural-functional electronic parts that satisfy the requirements of lightweight,excell... Mg alloy matrix composites reinforced with short carbon fibers(C_(sf)/Mg)are considered as potential candidates for integrated structural-functional electronic parts that satisfy the requirements of lightweight,excellent mechanical properties,and heat dissipation.However,the different characteristics of C_(sf)and Mg alloy make the interface a critical issue affecting the synergistic improvement of thermal and mechanical properties of the composites.Here,Cu coating with different thicknesses is introduced to modify the C_(sf)/Mg interface,so as to simultaneously enhance the thermal and mechanical performances,which can combine the advantages of coating modification and matrix alloying.Results reveal that thermal diffusivity(TD)of 3-C_(sf)-Cu/Mg composites is as high as 22.12 mm^(2)/s and an enhancement of 52.97%is achieved compared with C_(sf)/Mg composites,as well as 16.3%enhancement of ultimate compressive strength(UCS)in the longitudinal direction,8.84%improvement of UCS in the transverse direction,and 53.08%increasement of ultimate tensile strength(UTS).Such improvement can be ascribed to the formation of intermetallic compounds.The formation of intermetallic compounds can not only effectively alleviate the lattice distortion of the matrix and decrease interfacial thermal resistance,but also bear the loads.Our work is of great significance for designing C_(sf)/Mg composites with integrated structure and function. 展开更多
关键词 Magnesium matrix composites Cu coating thickness Intermetallic compounds Thermal performances Mechanical properties
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Synthesis and high frequency structure simulator electromagnetic simulation of hollow NC@CeO_(2)nanospheres for broad absorption bandwidth 被引量:1
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作者 Shuhao Yang Peiyan Zhao +5 位作者 Xianyong Lu Xiaoyuan Hao Yufan Wu Huiya Wang Tao Zhou Guangsheng Wang 《International Journal of Minerals,Metallurgy and Materials》 2025年第3期678-688,共11页
Recent progress in microwave absorption materials stimulates the extensive exploration of rare earth oxide materials.Herein,we report the synthesis of a hollow sphere-based carbon material compounded with rare earth o... Recent progress in microwave absorption materials stimulates the extensive exploration of rare earth oxide materials.Herein,we report the synthesis of a hollow sphere-based carbon material compounded with rare earth oxides.Hollow N-doped carbon nano-spheres loaded ceria composites(H-NC@CeO_(2))were designed and prepared by the template method,combined with in-situ coating,pyrolysis and chemical etching.By controlling the loading content of H-NC@CeO_(2)and adjusting the impedance matching of the material,the H-NC@CeO_(2)/PS(polystyrene)composite exhibited a minimum reflection loss(RL)of-50.8 dB and an effective absorption band-width(EAB)of 4.64 GHz at a filler ratio of 20wt%and a thickness of 2 mm.In accordance with measured electromagnetic parameters,simulations using the high frequency structure simulator(HFSS)software were conducted to investigate the impact of the honeycomb structure on the electromagnetic wave performance of H-NC@CeO_(2)/PS.By calculating the surface electric field and the material’s bulk loss density,the mechanism of electromagnetic loss for the honeycomb structure was elaborated.A method for structural design and man-ufacturing of broadband absorbing devices was proposed and a broadband absorber with an EAB of 11.9 GHz was prepared.This study presents an innovative approach to designing advanced electromagnetic(EM)wave absorbing materials with broad absorption band-widths. 展开更多
关键词 rare earth oxides carbon matrix composites hollow structure electromagnetic simulation
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DFEFM:Fusing frequency correlation and mel features for robust edge bird audio detection 被引量:1
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作者 Yingqi Wang Luyang Zhang +2 位作者 Jiangjian Xie Junguo Zhang Rui Zhu 《Avian Research》 2025年第2期199-207,共9页
Passive acoustic monitoring(PAM)technology is increasingly becoming one of the mainstream methods for bird monitoring.However,detecting bird audio within complex natural acoustic environments using PAM devices remains... Passive acoustic monitoring(PAM)technology is increasingly becoming one of the mainstream methods for bird monitoring.However,detecting bird audio within complex natural acoustic environments using PAM devices remains a significant challenge.To enhance the accuracy(ACC)of bird audio detection(BAD)and reduce both false negatives and false positives,this study proposes a BAD method based on a Dual-Feature Enhancement Fusion Model(DFEFM).This method incorporates per-channel energy normalization(PCEN)to suppress noise in the input audio and utilizes mel-frequency cepstral coefficients(MFCC)and frequency correlation matrices(FCM)as input features.It achieves deep feature-level fusion of MFCC and FCM on the channel dimension through two independent multi-layer convolutional network branches,and further integrates Spatial and Channel Synergistic Attention(SCSA)and Multi-Head Attention(MHA)modules to enhance the fusion effect of the aforementioned two deep features.Experimental results on the DCASE2018 BAD dataset show that our proposed method achieved an ACC of 91.4%and an AUC value of 0.963,with false negative and false positive rates of 11.36%and 7.40%,respectively,surpassing existing methods.The method also demonstrated detection ACC above 92%and AUC values above 0.987 on datasets from three sites of different natural scenes in Beijing.Testing on the NVIDIA Jetson Nano indicated that the method achieved an ACC of 89.48%when processing an average of 10 s of audio,with a response time of only 0.557 s,showing excellent processing efficiency.This study provides an effective method for filtering non-bird vocalization audio in bird vocalization monitoring devices,which helps to save edge storage and information transmission costs,and has significant application value for wild bird monitoring and ecological research. 展开更多
关键词 Bird audio detection Dual-feature fusion Frequency correlation matrix Passive acoustic monitoring
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