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3D MERGE与3D SPACE STIR序列在腰椎间盘突出症检查中的应用比较 被引量:3
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作者 李兰 殷小丹 +2 位作者 李旭雪 吴海燕 张滔 《中国医学物理学杂志》 CSCD 2024年第1期27-31,共5页
目的:对比三维多回波恢复梯度回波(3D MERGE)、三维可变反转角快速自旋回波(3D SPACE STIR)序列在腰椎间盘突出症(LDH)检查中的应用效果。方法:选择2020年1月~2022年11月收治的135例LDH患者,回顾性分析患者临床和磁共振成像(MRI)资料,... 目的:对比三维多回波恢复梯度回波(3D MERGE)、三维可变反转角快速自旋回波(3D SPACE STIR)序列在腰椎间盘突出症(LDH)检查中的应用效果。方法:选择2020年1月~2022年11月收治的135例LDH患者,回顾性分析患者临床和磁共振成像(MRI)资料,所有患者均接受常规MRI扫描及3D MERGE、3D SPACE STIR序列扫描,对比3D MERGE、3D SPACE STIR序列测量神经根直径的一致性,评价两种序列的图像质量参数[信噪比(SNR)、对比噪声比(CNR)]、图像清晰度评分。结果:3D MERGE和3D SPACE STIR序列测量的L3~S1神经根直径比较差异无统计学意义(P>0.05),且两组序列测量的L3、L4、L5和S1直径均显示出较高相关性(r=0.957,0.986,0.975,0.972,P<0.05);3D MERGE序列的SNR及CNR均高于3D SPACE STIR序列,神经根显示分级、图像清晰度评分优于3D SPACE STIR序列,差异有统计学意义(P<0.05)。结论:3D MERGE、3D SPACE STIR序列在LDH神经根直径测量中具有极高一致性,3D MERGE序列较3D SPACE STIR序列能够更清晰显示神经跟的解剖形态,图像质量更好。 展开更多
关键词 腰椎间盘突出症 3D merge 3D SPACE STIR 神经根直径 图像质量
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一种改进的Split-Merge图像分割算法 被引量:4
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作者 谢钧 俞璐 吴乐南 《计算机应用》 CSCD 北大核心 2008年第7期1744-1746,共3页
图像分割的经典算法Split-Merge算法思路简洁、运算效率高,但存在边界定位不准确和过分割等问题。针对过分割问题提出了一种改进的Split-Merge算法,在合并过程中引入全局目标函数,并在目标函数中定义了长度项,使用贪心法完成合并过程。... 图像分割的经典算法Split-Merge算法思路简洁、运算效率高,但存在边界定位不准确和过分割等问题。针对过分割问题提出了一种改进的Split-Merge算法,在合并过程中引入全局目标函数,并在目标函数中定义了长度项,使用贪心法完成合并过程。长度项以及贪心法的使用促使相邻区域充分合并,有效地克服了过分割等问题,取得了较好的分割效果。 展开更多
关键词 图像分割 splitmerge算法 贪心法
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改进Split-Merge分割用于蝗虫图像 被引量:2
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作者 张煜东 吴乐南 +1 位作者 韦耿 吴含前 《计算机工程与应用》 CSCD 北大核心 2009年第14期34-38,共5页
为了更好地分割蝗虫图像,对传统Split-Merge算法做出改进:用PCNN来进行分裂,采用一种简化的Mumford-Shah模型进行合并。该方法的优点是:分裂阶段不仅无效分割数目减少,而且无方块效应,对边缘定位准确;合并阶段能够理想地将分裂后的区域... 为了更好地分割蝗虫图像,对传统Split-Merge算法做出改进:用PCNN来进行分裂,采用一种简化的Mumford-Shah模型进行合并。该方法的优点是:分裂阶段不仅无效分割数目减少,而且无方块效应,对边缘定位准确;合并阶段能够理想地将分裂后的区域合并为感兴趣的前景与不感兴趣的背景,误合并与欠合并大幅减小。实验对成虫与幼虫图像均进行分割。综合比较,该算法性能较优。 展开更多
关键词 图像分割 分裂合并法 脉冲耦合神经网络
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基于PCNN的改进Split-merge图像分割 被引量:2
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作者 张煜东 吴乐南 韦耿 《数据采集与处理》 CSCD 北大核心 2010年第3期353-357,共5页
为了更好地分割图像,对传统Split-merge算法作出改进:PCNN先进行分裂,用一种简化的Mumford-Shah模型进行合并,使得分裂阶段不仅无效分割减少,而且无方块效应,对边缘定位准确;合并阶段能够理想地将分裂后的区域合并为感兴趣的前景与不感... 为了更好地分割图像,对传统Split-merge算法作出改进:PCNN先进行分裂,用一种简化的Mumford-Shah模型进行合并,使得分裂阶段不仅无效分割减少,而且无方块效应,对边缘定位准确;合并阶段能够理想地将分裂后的区域合并为感兴趣的前景与不感兴趣的背景,误合并与欠合并大幅减小。对Papav,Monkey,Twoman图像的仿真表明,其分割结果和运行时间均优于AMS,MBMS算法。仿真结果证明,本文算法是一种适用于图像分割的有效算法。 展开更多
关键词 图像分割 分裂合并法 脉冲耦合神经网
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在Split-Merge框架下进行基于图的图像分割
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作者 俞璐 吴乐南 谢钧 《数据采集与处理》 CSCD 北大核心 2009年第3期300-303,共4页
Split-Merge算法是图像分割领域的经典算法,思路简洁、运算效率高,但因分裂位置和形状固定,导致出现方块效应和边界定位不准确等问题。现有的各种改进算法不能从根本上解决这些问题,为此本文将基于图的分割算法纳入到Split-Merge框架中... Split-Merge算法是图像分割领域的经典算法,思路简洁、运算效率高,但因分裂位置和形状固定,导致出现方块效应和边界定位不准确等问题。现有的各种改进算法不能从根本上解决这些问题,为此本文将基于图的分割算法纳入到Split-Merge框架中来,提出了在Split-Merge框架下进行基于图的分割。新算法把传统的基于图割值的算法作为分裂阶段的处理手段,在合并阶段采用本文提出的一种与访问次序无关的合并算法。新算法既解决了Split-Merge算法中因分裂位置和形状固定而带来的各种问题,也有效地消除了在基于图的分割中常见的"过分割"现象,取得了满意的分割效果。 展开更多
关键词 图像分割 splitmerge算法 基于图的分割
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中医药多元证据整合方法学MERGE框架 被引量:9
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作者 赖鸿皓 王浙 +12 位作者 李滢 唐文静 王蓓蓓 孙培栋 孙铭谣 黄嘉杰 肖志攀 李颖 赵晨 商洪才 杨克虎 刘杰 葛龙 《协和医学杂志》 CSCD 北大核心 2024年第1期172-182,共11页
在循证医学时代下,依托规范的技术方法和标准化的操作规程发掘中医药独特优势,是实现中医药现代化、国际化发展并惠泽人类的必由之路。中医理论、人用经验和研究证据三结合证据体系的提出标志着中医药特色评价体系思维方法取得了重要进... 在循证医学时代下,依托规范的技术方法和标准化的操作规程发掘中医药独特优势,是实现中医药现代化、国际化发展并惠泽人类的必由之路。中医理论、人用经验和研究证据三结合证据体系的提出标志着中医药特色评价体系思维方法取得了重要进步,经过恰当方法整合后的多元证据体是中医药临床指南推荐意见和循证卫生决策的有力支撑。本文基于当前国际证据合成与分级方法学前沿进展,初步提出中医药多元证据整合的方法学框架——MERGE(Merge Evidence-based Research and artificial intelliGence to support smart dEcision)框架,以期为中医药循证医学方法学体系的完善和发展提供借鉴和参考。 展开更多
关键词 循证医学 中医药 多元证据 证据整合 merge框架
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基于分类估计的异质数据融合M_(split)模型
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作者 陶叶青 束明聪 陈浩 《淮阴师范学院学报(自然科学版)》 2025年第1期45-51,共7页
从分类估计的角度研究异质数据融合理论,建立一种不依赖于随机模型的融合方法.该理论首先基于M_(split)估计对观测数据进行分类估计,然后根据分类估计结果,应用中位函数计算不同参数估值的中误差,最后通过定义尺度因子与相对权比函数构... 从分类估计的角度研究异质数据融合理论,建立一种不依赖于随机模型的融合方法.该理论首先基于M_(split)估计对观测数据进行分类估计,然后根据分类估计结果,应用中位函数计算不同参数估值的中误差,最后通过定义尺度因子与相对权比函数构建融合模型,实现异质数据的有效融合.通过两类不同精度量级的观测数据组成的控制测量实例对该方法进行验证,结果表明,该方法易于实现,得到的参数估值稳定. 展开更多
关键词 异质数据融合 分类估计 M_(split)估计 尺度因子 融合模型
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MRI 3D-MERGE序列对三角纤维软骨复合体损伤的诊断价值 被引量:1
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作者 罗铧 王浩东 +1 位作者 吴海燕 李东明 《中国CT和MRI杂志》 2024年第10期147-149,共3页
目的探讨MRI三维-多回波恢复梯度回波(three dimensional-multiple-echo recalled gradient echo,3D-MERGE)序列在腕关节三角纤维软骨复合体(triangular fib roc a rt ilage complex,TFCC)损伤中的诊断价值。方法回顾性分析四川省骨科医... 目的探讨MRI三维-多回波恢复梯度回波(three dimensional-multiple-echo recalled gradient echo,3D-MERGE)序列在腕关节三角纤维软骨复合体(triangular fib roc a rt ilage complex,TFCC)损伤中的诊断价值。方法回顾性分析四川省骨科医院2021年1月-2022年1月因腕尺侧疼痛就诊的76例患者的临床资料,其中男性35例,女性41例,年龄16-52岁,平均年龄39.6岁。所有患者行腕关节MRI 3D-MERGE序列检查,并在随后接受腕关节镜手术。将TFCC损伤分为中心型损伤和边缘型损伤。以腕关节镜结果为金标准,探讨分析MRI 3D-MERGE序列诊断TFCC损伤的敏感度、特异度。结果腕关节镜检查确诊TFCC损伤者60例,其中中心型16例,边缘型28例,中心型和边缘型损伤同时存在16例;MRI 3D-MERGE序列检查TFCC损伤70例,中心型13例,边缘型35例,22例同时存在中心型和边缘型损伤。对比得出MRI 3D-MERGE序列诊断TFCC损伤中心型损伤的敏感度、特异度分别为0.93、0.89,边缘型损伤的敏感度、特异度分别为0.80、0.62。结论MRI3D-MERGE序列对TFCC损伤有较高的诊断价值,但相对于中心型损伤,MRI 3D-MERGE序列对边缘型损伤显示较低的特异度,因此在临床中,对于MRI提示的边缘型损伤患者,医师还需结合患者临床病史和体格检查进行谨慎诊断。 展开更多
关键词 三角纤维软骨 腕损伤 3D-merg序列 磁共振成像
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A New Merged Product Reveals Precipitation Features over Drylands in China
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作者 Min LUO Yuzhi LIU +5 位作者 Jie GAO Run LUO Jinxia ZHANG Ziyuan TAN Siyu CHEN Khan ALAM 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第10期2079-2091,共13页
Due to the considerable uncertainties inherent in the datasets describing the spatiotemporal distributions of precipitation in the drylands of China,this study presents a new merged monthly precipitation product with ... Due to the considerable uncertainties inherent in the datasets describing the spatiotemporal distributions of precipitation in the drylands of China,this study presents a new merged monthly precipitation product with a spatial resolution of approximately 0.2°×0.2°during 1980–2019.The newly developed precipitation product was validated at different temporal scales(e.g.,monthly,seasonally,and annually).The results show that the new product consistently aligns with the spatiotemporal distributions reported by the Chinese Meteorological Administration Land Data Assimilation System(CLDAS)product and Multi-Source Weighted Ensemble Precipitation(MSWEP).The merged product exhibits exceptional quality in describing the drylands of China,with a bias of–2.19 mm month^(–1)relative to MSWEP.In addition,the annual trend of the merged product(0.09 mm month^(–1)yr^(−1))also closely aligns with that of the MSWEP(0.11 mm month^(–1)yr^(−1))during 1980–2019.The increasing trend indicates that the water cycle and wetting process intensified in the drylands of China during this period.In particular,there was an increase in wetting during the period from 2001–2019.Generally,the merged product exhibits potential value for improving our understanding of the climate and water cycle in the drylands of China. 展开更多
关键词 PRECIPITATION merged dataset DRYLANDS water cycle
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Direct seawater splitting for hydrogen production:Recent advances in materials synthesis and technological innovation
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作者 Yilin Zhao Zhipeng Yu +4 位作者 Aimin Ge Lujia Liu Joaquim Luis Faria Guiyin Xu Meifang Zhu 《Green Energy & Environment》 SCIE EI CAS 2025年第1期11-33,共23页
Direct seawater splitting has emerged as a popular and promising research direction for synthesising clean,green,non-polluting,and sustainable hydrogen energy without depending on high-purity water in the face of the ... Direct seawater splitting has emerged as a popular and promising research direction for synthesising clean,green,non-polluting,and sustainable hydrogen energy without depending on high-purity water in the face of the world’s shortage of fossil energy.However,efficient seawater splitting is hindered by slow kinetics caused by the ultra-low conductivity and the presence of bacteria,microorganisms,and stray ions in seawater.Additionally,producing hydrogen on an industrial scale is challenging due to the high production cost.The present review addresses these challenges from the catalyst point of view,namely,that designing catalysts with high catalytic activity and stability can directly affect the rate and effect of seawater splitting.From the ion transfer perspective,designing membranes can block harmful ions,improving the stability of seawater splitting.From the energy point of view,mixed seawater systems and self-powered systems also provide new and low-energy research systems for seawater splitting.Finally,ideas and directions for further research on direct seawater splitting in the future are pointed out,with the aim of achieving low-cost and high-efficiency hydrogen production. 展开更多
关键词 Seawater splitting CATALYST Membranes Mixed seawater systems Self-powered systems
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Bimetallic Single‑Atom Catalysts for Water Splitting
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作者 Megha A.Deshmukh Aristides Bakandritsos Radek Zbořil 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期1-45,共45页
Green hydrogen from water splitting has emerged as a critical energy vector with the potential to spearhead the global transition to a fossil fuel-independent society.The field of catalysis has been revolutionized by ... Green hydrogen from water splitting has emerged as a critical energy vector with the potential to spearhead the global transition to a fossil fuel-independent society.The field of catalysis has been revolutionized by single-atom catalysts(SACs),which exhibit unique and intricate interactions between atomically dispersed metal atoms and their supports.Recently,bimetallic SACs(bimSACs)have garnered significant attention for leveraging the synergistic functions of two metal ions coordinated on appropriately designed supports.BimSACs offer an avenue for rich metal–metal and metal–support cooperativity,potentially addressing current limitations of SACs in effectively furnishing transformations which involve synchronous proton–electron exchanges,substrate activation with reversible redox cycles,simultaneous multi-electron transfer,regulation of spin states,tuning of electronic properties,and cyclic transition states with low activation energies.This review aims to encapsulate the growing advancements in bimSACs,with an emphasis on their pivotal role in hydrogen generation via water splitting.We subsequently delve into advanced experimental methodologies for the elaborate characterization of SACs,elucidate their electronic properties,and discuss their local coordination environment.Overall,we present comprehensive discussion on the deployment of bimSACs in both hydrogen evolution reaction and oxygen evolution reaction,the two half-reactions of the water electrolysis process. 展开更多
关键词 Single-atom catalysts Single-atom dimers Hydrogen evolution Oxygen evolution Water splitting
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基于Split-GFP系统定量分析大肠杆菌中异源表达的类胶原蛋白Scl2
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作者 色依德·斯马依 赵晨旭 +3 位作者 张轶群 刘业学 王稳航 李玉 《天津科技大学学报》 2025年第1期13-19,27,共8页
利用大肠杆菌(Escherichia coli)表达类胶原蛋白Scl2,并通过Split-GFP系统建立一种简便、快速且可定量检测Scl2的方法。结果表明,Scl2在大肠杆菌(Escherichia coli)BL21(DE3)中成功表达,并通过His亲和标签纯化得到较高纯度的Scl2。圆二... 利用大肠杆菌(Escherichia coli)表达类胶原蛋白Scl2,并通过Split-GFP系统建立一种简便、快速且可定量检测Scl2的方法。结果表明,Scl2在大肠杆菌(Escherichia coli)BL21(DE3)中成功表达,并通过His亲和标签纯化得到较高纯度的Scl2。圆二色光谱和差示扫描量热仪分析发现,Scl2的二级结构和热稳定性与动物源Ⅰ型胶原蛋白相似,并且GFP11的融合对其几乎没有影响。GFP1-10和Scl2-GFP11结合的前20 h的结合速度较高,达到最大相对荧光强度需要约70 h。当两者结合1 h时,Scl2-GFP11蛋白质量浓度与相对荧光强度之间能够形成较好的线性关系,相关系数R2为0.9995,重复性良好。本研究利用Split-GFP系统建立了体外检测并定量分析Scl2的方法,为下一步高通量筛选研究提供了快速、简便的工具。 展开更多
关键词 大肠杆菌 异源表达 类胶原蛋白Scl2 split-GFP 蛋白定量分析
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Metal nanoparticles decorated CoFe-(oxy)hydroxysulfides nanosheets fabricated by a general strategy for electrocatalytic water splitting
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作者 Xiaodong Yang Haochen Shen +7 位作者 Xiaoming Xiao Zhichao Li Qi Zhou Wei Yang Bin Jiang Yongli Sun Luhong Zhang Zhenhua Yan 《Journal of Energy Chemistry》 2025年第1期26-38,共13页
This study presents a novel method to fabricate metal-decorated,sulfur-doped layered double hydroxides(M/SLDH)through spontaneous redox and sulfurization processes.The developed Ag/SLDH and Pt/SLDH catalysts with abun... This study presents a novel method to fabricate metal-decorated,sulfur-doped layered double hydroxides(M/SLDH)through spontaneous redox and sulfurization processes.The developed Ag/SLDH and Pt/SLDH catalysts with abundant heterogeneous interfaces and hierarchical nanostructures demonstrated outstanding oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)performance,achieving low overpotentials of 212 and 35 mV at 10 mA cm^(-2)in 1 M KOH,respectively.As both anode and cathode in water splitting,they required only 1.47 V to reach 10 mA cm^(-2)and exhibited high structural robustness,maintaining stability at 1000 mA cm^(-2)for 300 h.In-situ Raman analysis revealed that the synergistic effects of metal nanoparticles and S doping significantly promote the transformation into the S-Co1-xFexOOH layer,which serves as the active phase for water oxidation.Additionally,ultraviolet photoelectron spectroscopy(UPS)and density functional theory(DFT)analyses indicated that incorporating metal nanoparticles and S doping increase electron density near the Fermi level and reduce reaction energy barriers,thus enhancing intrinsic OER and HER activities.This study provides a scalable strategy for synthesizing high-performance electrocatalysts for water splitting,with promising potential for broader applications. 展开更多
关键词 LDH Spontaneous reaction Metal nanoparticles Water splitting
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Electronic modulation towards MOFs as template derived CoP via engineered heteroatom defect for a highly effcient overall water splitting
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作者 Meijie Ding Zhiqiang Wei +6 位作者 Dexue Liu Wenhua Zhao Qiang Lu Zhiming Li Qingsong Yu Chenggong Lu Hua Yang 《Journal of Energy Chemistry》 2025年第2期598-607,I0012,共11页
The reasonable design of material morphology and eco-friendly electrocatalysts are essential to highly efficient water splitting.It is proposed that a promising strategy effectively regulates the electronic structure ... The reasonable design of material morphology and eco-friendly electrocatalysts are essential to highly efficient water splitting.It is proposed that a promising strategy effectively regulates the electronic structure of the d-orbitals of CoP using cerium doping in this paper,thus significantly improving the intrinsic property and conductivity of CoP for water splitting.As a result,the as-synthesize porous Ce-doped CoP micro-polyhedron composite derived from Ce-ZIF-67 as bifunctional electrocatalytic materials exhibits excellent electrocatalytic performance in both the oxygen evolution reaction(OER)and the hydrogen evolution reaction(HER),overpotentials of about 152 mV for HER at 10 mA cm^(-2)and about 352 mV for OER at 50 mA cm^(-2),and especially it shows outstanding long-term stability.Besides,an alkaline electrolyzer,using Ce0.04Co0.96P electrocatalyst as both the anode and cathode,delivers a cell voltage value of1.55 V at the current density of 10 mA cm^(-2).The calculation results of the density functional theory(DFT)demonstrate that the introduction of an appropriate amount of Ce into CoP can enhance the conductivity,and can induce the electronic modulation to regulate the selective adsorption of reaction intermediates on catalytic surface and the formation of O*intermediates(CoOOH),which exhibits an excellent electrocatalytic performance.This study provides novel insights into the design of an extraordinary performance water-splitting of the multicomponent electrocatalysts. 展开更多
关键词 Hydrogen evolution CERIUM PHOSPHIDES Oxygen evolution Water splitting
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Dual mediators promote charge transfer of hematite photoanode for durable photoelectrocatalytic water splitting
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作者 Yuanyuan Jiang Yan Zhang +3 位作者 Mengmeng Liu Lulu Liu Hong Chen Sheng Ye 《Chinese Journal of Catalysis》 2025年第2期75-83,共9页
Regulating the interfacial charge transfer is pivotal for elucidating the kinetics of engineering the interface between the light-harvesting semiconductor and the substrate/catalyst for photoelectrocatalytic water spl... Regulating the interfacial charge transfer is pivotal for elucidating the kinetics of engineering the interface between the light-harvesting semiconductor and the substrate/catalyst for photoelectrocatalytic water splitting.In this study,we constructed a superior Ti-doped hematite photoanode(TiFeO)by employing SnOx as an electron transfer mediator,partially oxidized graphene(pGO)as a hole transfer mediator,and molecular Co cubane as a water oxidation catalyst.The Co/pGO/TiFeO/SnO_(x)integrated system achieves a photocurrent density of 2.52 mA cm–2 at 1.23 VRHE,which is 2.4 times higher than bare photoanode(1.04 mA cm^(-2)),with operational stability up to 100 h.Kinetic measurements indicate that pGO can promote charge transfer from TiFeO to the Co cubane catalyst.In contrast,SnOx reduces charge recombination at the interface between TiFeO and the fluorinated tin oxide substrate.In-situ infrared spectroscopy shows the formation of an O–O bonded intermediate during water oxidation.This study highlights the crucial role of incorporating dual charge-transfer mediators into photoelectrodes for efficient solar energy conversion. 展开更多
关键词 HEMATITE Molecular catalyst Charge transfer mediator Photoelectrocatalytic water splitting
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Effects of Split Injection on Combustion,Emissions,and Intermediate Species of Natural Gas High-Pressure Direct Injection Engine
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作者 Lijiang Wei Xiuwei Lu +1 位作者 Wenqing Huang Qimin Song 《哈尔滨工程大学学报(英文版)》 2025年第1期210-223,共14页
Using natural gas(NG)as the primary fuel helps alleviate the fossil fuel crisis while reducing engine soot and nitrogen oxide(NO_(X))emissions.In this paper,the influences of a novel split injection concept on an NG h... Using natural gas(NG)as the primary fuel helps alleviate the fossil fuel crisis while reducing engine soot and nitrogen oxide(NO_(X))emissions.In this paper,the influences of a novel split injection concept on an NG high pressure direct injection(HPDI)engine are examined.Four typical split injection strategies,namely split pre-injection of pilot diesel(PD)and NG,split post-injection of PD and NG,split pre-injection of NG,and split post-injection of PD,were developed to investigate the influences on combustion and emissions.Results revealed that split pre injection of NG enhanced the atomization of PD,whereas the split post-injection of NG lowered the temperature in the core region of the PD spray,resulting in the deterioration of combustion.The effect of the split injection strategy on indicated thermal efficiency exceeded 7.5%.Split pre-injection was favorable to enhancing thermal efficiency,whereas split post-injection was not.Ignition delay,combustion duration,and premixed combustion time proportion were affected by injection strategies by 3.8%,50%,and 19.7%,respectively.Split pre-injection increased CH_(4) emission in the exhaust.Split post-injection,especially split post-injection of PD and NG,reduced the unburned CH_(4) emission by approximately 30%.When the split post-injection ratio was less than 30%,the trade-off between NO_(X) and soot was interrupted.The distribution range of hydroxyl radicals was expanded by pre-injection,and NO_(X) was generated in the region where the NG jet hit the wall.This paper provides valuable insights into the optimization of HPDI injection parameters. 展开更多
关键词 High pressure direct injection Natural gas split injection strategy Injection ratio COMBUSTION
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Porous Microreactor Chip for Photocatalytic Seawater Splitting over 300 Hours at Atmospheric Pressure
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作者 Desheng Zhu Zhipeng Dong +9 位作者 Chengmei Zhong Junhong Zhang Qi Chen Ni Yin Wencheng Jia Xiong Zheng Fengzai Lv Zhong Chen Zhenchao Dong Wencai Huang 《Nano-Micro Letters》 2025年第8期251-263,共13页
Photocatalytic seawater splitting is an attractive way for producing green hydrogen.Significant progresses have been made recently in catalytic efficiencies,but the activity of catalysts can only maintain stable for a... Photocatalytic seawater splitting is an attractive way for producing green hydrogen.Significant progresses have been made recently in catalytic efficiencies,but the activity of catalysts can only maintain stable for about 10 h.Here,we develop a vacancy-engineered Ag_(3)PO_(4)/CdS porous microreactor chip photocatalyst,operating in seawater with a performance stability exceeding 300 h.This is achieved by the establishment of both catalytic selectivity for impurity ions and tailored interactions between vacancies and sulfur species.Efficient transport of carriers with strong redox ability is ensured by forming a heterojunction within a space charge region,where the visualization of potential distribution confirms the key design concept of our chip.Moreover,the separation of oxidation and reduction reactions in space inhibits the reverse recombination,making the chip capable of working at atmospheric pressure.Consequently,in the presence of Pt co-catalysts,a high solar-to-hydrogen efficiency of 0.81%can be achieved in the whole durability test.When using a fully solar-driven 256 cm2 hydrogen production prototype,a H_(2) evolution rate of 68.01 mmol h−1 m−2 can be achieved under outdoor insolation.Our findings provide a novel approach to achieve high selectivity,and demonstrate an efficient and scalable prototype suitable for practical solar H_(2) production. 展开更多
关键词 Solar energy Hydrogen energy Photocatalytic seawater splitting Silver phosphate/Cadmium sulfide heterojunction
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Novel materials and techniques for photocatalytic water splitting developed by Professor Kazunari Domen
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作者 Yaqiang Wu Jianuo Li +2 位作者 Wei-Kean Chong Zhenhua Pan Qian Wang 《Chinese Journal of Catalysis》 2025年第1期1-50,共50页
Professor Kazunari Domen at the Shinshu University and the University of Tokyo has pioneered materials and techniques for solar-driven water splitting using photocatalysts,a promising technology for contributing to th... Professor Kazunari Domen at the Shinshu University and the University of Tokyo has pioneered materials and techniques for solar-driven water splitting using photocatalysts,a promising technology for contributing to the construction of a sustainable and carbon-neutral society.In this paper,we summarize his groundbreaking contributions to photocatalytic water splitting and,more broadly,photocatalytic research.We highlight various novel functional photocatalytic materials,including oxides,(oxy)nitrides,and oxysulfides,along with innovative techniques such as cocatalyst engineering and Z-scheme system construction developed by the Domen Group.His team has also pioneered readily accessible and cost-effective photo(electro)chemical device fabrication methods,such as the particle-transfer method and thin-film-transfer method.Furthermore,their research has made significant contributions to understanding the(photo)catalytic mechanisms using advanced characterization techniques.Together with his research team,Professor Domen has set many milestones in the field of photocatalytic overall water splitting,notably demonstrating the first scalable and stable 100 m^(2)solar H_(2)production system using only water and sunlight.His work has revealed the potential for practical solar H2 production from water and sunlight,and highlighted the application of fundamental principles,combined with chemical and materials science tools,to design effective photocatalytic systems.Through this review,we focus on his research and the foundational design principles that can inspire the development of efficient photocatalytic systems for water splitting and solar fuel production.By building on his contributions,we anticipate a significant impact on addressing major global energy challenges. 展开更多
关键词 PHOTOCATALYSIS Water splitting Solar H_(2)production Solar energy conversion Artificial photosynthesis
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Recent advances in tantalum nitride for photoelectrochemical water splitting
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作者 Wenjie Yu Chao Feng +2 位作者 Ronghua Li Beibei Zhang Yanbo Li 《Chinese Journal of Catalysis》 2025年第1期51-82,共32页
Harnessing solar energy for renewable fuel production through artificial photosynthesis offers an ideal solution to the current energy and environmental crises.Among various methods,photoelectrochemical(PEC)water spli... Harnessing solar energy for renewable fuel production through artificial photosynthesis offers an ideal solution to the current energy and environmental crises.Among various methods,photoelectrochemical(PEC)water splitting stands out as a promising approach for direct solar-driven hydrogen production.Enhancing the efficiency and stability of photoelectrodes is a key focus in PEC water-splitting research.Tantalum nitride(Ta_(3)N_(5)),with its suitable band gap and band-edge positions for PEC water splitting,has emerged as a highly promising photoanode material.This review begins by introducing the history and fundamental characteristics of Ta_(3)N_(5),emphasizing both its advantages and challenges.It then explores methods to improve light absorption efficiency,charge separation and transfer efficiency,surface reaction rate,and the stability of Ta_(3)N_(5) photoanodes.Additionally,the review discusses the progress of research on tandem PEC cells incorporating Ta_(3)N_(5) photoanodes.Finally,it looks ahead to future research directions for Ta_(3)N_(5) photoanodes.The strategic approach outlined in this review can also be applied to other photoelectrode materials,providing guidance for their development. 展开更多
关键词 Photoelectrochemical water splitting Tantalum nitride Lightabsorption efficiency Charge separation and transfer EFFICIENCY Surfacereaction rate STABILITY
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Joint Flow Splitting,Sorting and Selecting for CQF Scheduling in TSN
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作者 Ma Tao Zhou Feifei +2 位作者 Guan Ti Jiang Qinru Yu Yang 《China Communications》 2025年第4期268-280,共13页
The progress of modern industry has given rise to great requirements for network transmission latency and reliability in domains such as smart grid and intelligent driving.To address these challenges,the concept of Ti... The progress of modern industry has given rise to great requirements for network transmission latency and reliability in domains such as smart grid and intelligent driving.To address these challenges,the concept of Time-sensitive networking(TSN)is proposed by IEEE 802.1TSN working group.In order to achieve low latency,Cyclic queuing and forwarding(CQF)mechanism is introduced to schedule Timetriggered(TT)flows.In this paper,we construct a TSN model based on CQF and formulate the flow scheduling problem as an optimization problem aimed at maximizing the success rate of flow scheduling.The problem is tackled by a novel algorithm that makes full use of the characteristics and the relationship between the flows.Firstly,by K-means algorithm,the flows are initially partitioned into subsets based on their correlations.Subsequently,the flows within each subset are sorted by a new special criteria extracted from multiple features of flow.Finally,a flow offset selecting method based on load balance is used for resource mapping,so as to complete the process of flow scheduling.Experimental results demonstrate that the proposed algorithm exhibits significant advantages in terms of scheduling success rate and time efficiency. 展开更多
关键词 cyclic queuing and forwarding model joint flow splitting sorting and selecting timesensitive networking
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