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In-situ formation of a new cation renders perovskite solar modules with a record efficiency and long-term stability

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Science China Chemistry 2025年第2期68卷 409-410页

作者： Shanxiao lin Xixing Wen Xiuwen Xu College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023China

Over the past 14 years,the efficiency of perovskite solar cells has surged from 3.8% to 26.7%[1],establishing it as an unrivaled choice for next-generation ***,maintaining the long-term stability of perovskite solar modules(PSMs)remains a *** particular,the thermal-and light-induced changes in crystal structure,composition,and optoelectronic properties are the primary causes of device degradation,currently considered the Achilles’heel that hinders its commercialization[2–4].Now,writing in Science,Ding et al.[5]achieve a milestone by overcoming the thermal-and light-induced degradation,rendering the PSM with a record efficiency of 23.2% and a T80(time to 20% efficiency loss)over 4,000 h at 85℃ and 85%relative humidity(RH)under light *** key behind this milestone is to utilize the cation reactivity to in-situ form methyl tetrahydrotriazinium([MTTZ]+,a new cation)and dimethylammonium([DMA]+)in precursor solution(Figure 1a).These cations remarkably modulate perovskite crystallization and stabilize the perovskite.

关键词： perovskite stability modules

Upper Bounds on the Multicolor Ramsey Numbers r_(k)(C_(4))

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 286-294页

作者： Tian-yu LI Qi-zhong lin Center for Discrete Mathematics Fuzhou UniversityFuzhou 350108China

The multicolor Ramsey number r_(k)(C_(4))is the smallest integer N such that any k-edge coloring of KN contains a monochromatic C_(4).The current best upper bound of r_(k)(C_(4))was obtained by Chung(1974)and independently by Irving(1974),i.e.,r_(k)(C_(4))≤k^(2)+k+1 for all k≥*** is no progress on the upper bound since *** this paper,we improve the upper bound of r_(k)(C_(4))by showing that r_(k)(C_(4))≤k^(2)+k-1 for even k≥*** improvement is based on the upper bound of the Turan number ex(n,C4),in which we mainly use the double counting method and many novel ideas from Firke,Kosek,Nash,and Williford[***,Ser.B 103(2013),327-336].

关键词： Multicolor Ramsey number Turan number 4-cycle

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用于目标跟踪的特征融合孪生网络算法研究

厦门大学学报（自然科学版） 2022年第4期61卷 714-722页

作者：范东嘉林名强戴厚德仲训杲赵晶厦门理工学院电气工程与自动化学院福建厦门361024 中国科学院福建物质结构研究所泉州装备制造研究所福建晋江362216

针对目标跟踪过程存在的动态不确定性的问题,传统跟踪方法容易产生目标漂移甚至跟踪失败,而基于深度学习的跟踪算法随着网络结构的加深容易导致深层特征过于稀疏抽象,不利于克服上述问题.为此,本文提出SiamMask三分支网络融合注意力机... 详细信息

针对目标跟踪过程存在的动态不确定性的问题,传统跟踪方法容易产生目标漂移甚至跟踪失败,而基于深度学习的跟踪算法随着网络结构的加深容易导致深层特征过于稀疏抽象,不利于克服上述问题.为此,本文提出SiamMask三分支网络融合注意力机制的孪生网络目标跟踪新方法,旨在加强网络对特征选取的学习能力,加强目标有效特征的抽取,并减少冗余信息对网络负担的影响.特征提取主干网络选用改进的Resnet-50,通过融合深层和浅层特征,实现跟踪目标特征的有效表达.利用4个数据集(COCO、ImageNet-DET 2015、ImageNet-VID 2015、YouTube-VOS)对提出的特征融合孪生网络框架进行训练,并使用VOT数据集进行在线测试.实验表明:与文中其他跟踪方法相比,该算法在面对动态目标尺度变化、环境光照、运动模糊等场景表现更优异.

关键词：注意力机制目标跟踪深度学习孪生网络

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新型装配式喷射混凝土夹芯墙轴压试验研究

建筑结构 2022年第S2期52卷 1430-1436页

作者：惠婧谢群王欣林明强于周健济南大学土木建筑学院济南250022 山东建筑大学建筑结构加固改造与地下空间工程教育部重点实验室济南250014 日照市规划设计研究院日照276800

提出了一种新型装配式喷射混凝土夹芯墙板,该墙板由三部分以夹芯状排列构成,中间为预制泡沫混凝土板,两侧为喷射混凝土面层,面层内铺设钢丝网,沿墙板截面设置的暗柱与面层共同形成箱形结构部分。该墙板集承重、保温、隔热等功能于一体,... 详细信息

提出了一种新型装配式喷射混凝土夹芯墙板,该墙板由三部分以夹芯状排列构成,中间为预制泡沫混凝土板,两侧为喷射混凝土面层,面层内铺设钢丝网,沿墙板截面设置的暗柱与面层共同形成箱形结构部分。该墙板集承重、保温、隔热等功能于一体,具有轻质、安装快捷、现场施工效率高等特点。本文通过分级加载对墙板进行轴压试验,分析研究了该类墙板的破坏模式、承载能力、整体刚度等结构性能。试验结果表明,新型装配式喷射混凝土夹芯墙构件具有较高的承载能力与整体性。结合现有理论成果和本墙板特点,提出了修正后的受压承载力计算方法,通过与多个代表性设计理论对比验证,采用暗柱与夹芯墙叠加的方法误差最小,可为该墙板的应用提供技术依据。

关键词：喷射混凝土夹芯墙板暗柱装配式受压性能

双能X线骨密度仪检查及数字化X线摄影术用于骨搬移术后

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中国医学影像技术 2022年第12期38卷 1857-1861页

作者：王凯君谭新欢谭桂萍林明强杨文江山东省文登整骨医院放射科山东威海264400 山东省文登整骨医院骨手显微外科山东威海264400

目的观察骨搬移术后应用双能X线骨密度仪(DEXA)检查及数字化X线摄影术(DR)的价值。方法对19例因胫骨外伤致感染性骨不连及大面积骨缺损接受胫骨搬移术患者分别于术后2、4、6及8周、停止搬移即刻、停止搬移后4、8周、去外固定架前4周及... 详细信息

目的观察骨搬移术后应用双能X线骨密度仪(DEXA)检查及数字化X线摄影术(DR)的价值。方法对19例因胫骨外伤致感染性骨不连及大面积骨缺损接受胫骨搬移术患者分别于术后2、4、6及8周、停止搬移即刻、停止搬移后4、8周、去外固定架前4周及去外固定架即刻行DEXA和DR检查,观察不同时间点胫骨搬移区新生骨痂(BMD新生骨痂)和截骨上下端原骨质骨密度(BMD截骨上下端)及二者比率,分析DR图像中胫骨新生骨痂的形态及填充量。结果胫骨搬移术术后各时间点BMD新生骨痂、BMD截骨上下端及BMD比率总体差异均有统计学意义(P均0.05)。DR显示,术后4周胫骨搬移始区见新生骨痂影,随时间延长而呈多形态变化;术后2周胫骨搬移区未见新生骨痂填充,至停止搬移即刻新生骨痂填充量达25%,停止搬移4、8周达50%、75%,去外固定架前4周基本达100%。结论DEXA能动态监测骨搬移术后搬移区新生骨痂及截骨端原骨质BMD;DR可显示新生骨痂形态变化;骨搬移术后联合应用二者有助于评估预后。

关键词：骨折,骨骨密度骨痂 X线透视检查骨搬移术

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The profound review of Fenton process:What’s the next step?

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Journal of Environmental Sciences 2025年第1期147卷 114-130页

作者： Yimin lin Junlian Qiao Yuankui Sun Hongyu Dong State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Department of Environmental Science School of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China

Fenton and Fenton-like processes,which could produce highly reactive species to degrade organic contaminants,have been widely used in the field of wastewater ***,the chemistry of Fenton process including the nature of active oxidants,the complicated reactions involved,and the behind reason for its strongly pH-dependent performance,is the basis for the application of Fenton and Fenton-like processes in wastewater ***,the conflicting views still exist about the mechanism of the Fenton *** instance,reaching a unanimous consensus on the nature of active oxidants(hydroxyl radical or tetravalent iron)in this process remains *** review comprehensively examined the mechanism of the Fenton process including the debate on the nature of active oxidants,reactions involved in the Fenton process,and the behind reason for the pH-dependent degradation of contaminants in the Fenton ***,we summarized several strategies that promote the Fe(Ⅱ)/Fe(Ⅲ)cycle,reduce the competitive consumption of active oxidants by side reactions,and replace the Fenton reagent,thus improving the performance of the Fenton ***,advances for the future were proposed including the demand for the high-accuracy identification of active oxidants and taking advantages of the characteristic of target contaminants during the degradation of contaminants by the Fenton process.

关键词： Advanced oxidation process Fenton Hydroxyl radical Fe(IV) Wastewater treatment

Profiles,exposure assessment and expanded screening of PAHs and their derivatives in one petroleum refinery facility of China

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Journal of Environmental Sciences 2025年第1期147卷 550-560页

作者： Ning Wang Fengjiao Jiang lin Xu Yaqi Cai School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJinan 250101China Resource and Environmental Innovation Institute Shandong Jianzhu UniversityJinan 250101China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Environment Hangzhou Institute for Advanced StudyUCASHangzhou 330106China Hubei Key Laboratory of Environmental and Health Effects of Persistence Toxic Substances Institute of Environment and HealthJianghan UniversityWuhan 430056China

This study investigated environmental distribution and human exposure of polycyclic aromatic hydrocarbons(PAHs)and their derivatives in one Chinese petroleum refinery *** was found that,following with high concentrations of 16 EPA PAHs(∑Parent-PAHs)in smelting subarea of studied petroleum refinery facility,total derivatives of PAHs[named as XPAHs,including nitro PAHs(NPAHs),chlorinated PAHs(Cl-PAHs),and brominated PAHs(Br-PAHs)]in gas(mean=1.57×10^(4)ng/m^(3)),total suspended particulate(TSP)(mean=4.33×10^(3) ng/m^(3))and soil(mean=4.37×10^(3) ng/g)in this subarea had 1.76-6.19 times higher levels than those from other subareas of this facility,surrounding residential areas and reference areas,indicating that petroleum refining processes would lead apparent derivation of ***,compared with those in residential and reference areas,gas samples in the petrochemical areas had higher∑NPAH/∑PAHs(mean=2.18),but lower∑Cl-PAH/∑PAHs(mean=1.43×10^(-1))and∑Br-PAH/∑PAHs ratios(mean=7.49×10^(-2)),indicating the richer nitrification of PAHs than chlorination during petrochemical *** occupational exposure to PAHs and XPAHs in this petroleum refinery facility were 24-343 times higher than non-occupational exposure,and the ILCR(1.04×10^(-4))for petrochemical workers was considered to be potential high ***,one expanded high-resolution screening through GC Orbitrap/MS was performed for soils from petrochemical area,and another 35 PAHs were found,including alkyl-PAHs,phenyl-PAHs and other species,indicat-ing that profiles and risks of PAHs analogs in petrochemical areas deserve further expanded investigation.

关键词： Polycyclic aromatic hydrocarbons(PAHs) Derivatives Petroleum refinery Human exposure Non-targeted screening

Soil colloids can significantly enhance spreading of polybromodiphenyl ethers in groundwater by serving as an effective carrier

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Journal of Environmental Sciences 2025年第1期147卷 93-100页

作者： lin Duan Min Li Jiameng Liu Wei Chen College of Environmental Science and Engineering Ministry of Education Key Laboratory of Pollution Processes and Environmental CriteriaTianjin Key Laboratory of Environmental Remediation and Pollution ControlNankai UniversityTianjin 300350China

Polybromodiphenyl ethers(PBDEs),the widely used flame retardants,are common contaminants in surface soils at e-waste recycling *** association of PBDEs with soil colloids has been observed,indicating the potential risk to groundwater due to colloid-facilitated ***,the extent to which soil colloidsmay enhance the spreading of PBDEs in groundwater is largely ***,we report the co-transport of decabromodiphenyl ester(BDE-209)and soil colloids in saturated porous *** colloids released froma soil sample collected at an e-waste recycling site in Tianjin,China,contain high concentration of PBDEs,with BDE-209 being the most abundant conger(320±30 mg/kg).The colloids exhibit relatively high mobility in saturated sand columns,under conditions commonly observed in groundwater ***,under all the tested conditions(i.e.,varying flow velocity,pH,ionic species and ionic strength),the mass of eluted BDE-209 correlates linearly with that of eluted soil colloids,even though the mobility of the colloids varies markedly depending on the specific hydrodynamic and solution chemistry conditions ***,the mass of BDE-209 retained in the columns also correlates strongly with themass of retained ***,the PBDEs remain bound to soil colloids during transport in porous *** in this study indicate that soil colloidsmay significantly promote the transport of PBDEs in groundwater by serving as an effective *** might be the reason why the highly insoluble and adsorptive PBDEs are found in groundwater at some PBDE-contaminated sites.

关键词： Polybromodiphenyl ethers Soil colloids E-waste recycling sites Groundwater Facilitated transport

Projective Hilbert modules and sequential approximations

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Science China Mathematics 2025年第1期68卷 137-168页

作者： Lawrence G.Brown Huaxin lin Department of Mathematics Purdue UniversityWest LafayetteIN 47907-2067USA Department of Mathematics East China Normal UniversityShanghai 200062China Department of Mathematics University of OregonEugeneOR 97405USA

We show that when A is a separable C^(*)-algebra,every countably generated Hilbert A-module is projective(with bounded module maps as morphisms).We also study the approximate extensions of bounded module *** the case where A is aσ-unital simple C^(*)-algebra with strict comparison,and every strictly positive lower semicontinuous affine function on quasitraces can be realized as the rank of an element in the Cuntz semigroup,we show that the Cuntz semigroup is equivalent to unitarily equivalent classes of countably generated Hilbert A-modules if and only if A has stable rank one.

关键词： projective Hilbert modules simple C^(*)-algebras sequential approximations