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Keggin型杂多阴离子PW_(11)O_(39)Fe(Ⅲ)(H_2O)^(4-)电催化降解硝基苯

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化学学报 2009年第23期67卷 2650-2654页

作者：华英杰王崇太童叶翔张大帅张奇谷铁安胡佩海南师范大学化学与化工学院海口571158 海南省热带药用植物化学重点实验室海口571158 中山大学化学与化工学院广州510275

以Keggin型铁取代杂多阴离子PW11O39Fe(Ⅲ)(H2O)4-(PW11Fe)代替传统电芬顿(electro-Fenton)方法中的Fe3+作为电催化剂,构成一个新颖的电催化体系并用于中性水溶液中硝基苯的降解.结果表明,含有1.0mmol·L-1硝基苯和1.0mmol·L-1PW11Fe... 详细信息

以Keggin型铁取代杂多阴离子PW11O39Fe(Ⅲ)(H2O)4-(PW11Fe)代替传统电芬顿(electro-Fenton)方法中的Fe3+作为电催化剂,构成一个新颖的电催化体系并用于中性水溶液中硝基苯的降解.结果表明,含有1.0mmol·L-1硝基苯和1.0mmol·L-1PW11Fe的混合磷酸盐溶液(pH6.86),在-0.5V电位和60mL·min-1O2流速下反应100min,硝基苯便完全降解.降解的准一级表观速率常数与硝基苯的初始浓度有关,当硝基苯的初始浓度为1.0,2.0和5.0mmol·L-1时,kobs分别为7.18×10-2,3.57×10-2和1.47×10-2min-1.降解反应100min的TOC(有机碳总量)去除率约为35%,表明硝基苯的降解过程伴随着矿化.

关键词：铁取代杂多阴离子电催化硝基苯降解矿化率

表面等离子体共振效应在光电催化中的应用及机理研究

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光散射学报 2018年第3期30卷 236-244页

作者：杨皓方萍萍童叶翔中山大学化学学院广州510275

面对日益严峻的能源和环境问题,人们对可再生能源的需求日益增强。本文通过以金为核的二元及三元纳米粒子,设计了一种表面等离子体共振(surface plasmonic resonance,SPR)增强的光电催化剂。其中,金核通过SPR效应在光照下产生光热效应... 详细信息

面对日益严峻的能源和环境问题,人们对可再生能源的需求日益增强。本文通过以金为核的二元及三元纳米粒子,设计了一种表面等离子体共振(surface plasmonic resonance,SPR)增强的光电催化剂。其中,金核通过SPR效应在光照下产生光热效应及光电效应,提高了材料的催化活性。光照条件下纳米粒子表面的局域热点温度可以通过4-甲氧基异腈苯探针分子利用表面增强拉曼光谱得到。同时利用对氨基苯硫酚(PATP)探针分子证实SPR产生的光电催化效应。最重要的是,通过定量计算得到了光热效应及光电效应在SPR增强的光电催化性能各自的贡献。这些结果为表面等离子体共振协助增强的光电催化反应提供理论依据,并为新型光电催化材料提供了新的设计思路。

关键词：金纳米粒子表面等离子体共振光电催化表面增强拉曼光谱

尿素-NaBr低温熔盐中Fe^(2+)和Sm^(3+)的电化学行为及其诱导共沉积

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中国稀土学报 2002年第1期20卷 11-15页

作者：童叶翔刘鹏刘莉治杨绮琴中山大学化学与化工学院广州广东510275

利用循环伏安法、计时电位法和计时电流法 ,研究了尿素$CNaBr熔盐中Fe2 +在Pt,Cu ,Ag及Ti电极上的电化学行为 ,获知Fe2 +电还原为金属铁是一步不可逆过程 ,扩散系数为 2 74× 10 - 6cm2 ·s- 1 ,交换电流密度为 2 6 8× 10 - 5A·cm-... 详细信息

利用循环伏安法、计时电位法和计时电流法 ,研究了尿素$CNaBr熔盐中Fe2 +在Pt,Cu ,Ag及Ti电极上的电化学行为 ,获知Fe2 +电还原为金属铁是一步不可逆过程 ,扩散系数为 2 74× 10 - 6cm2 ·s- 1 ,交换电流密度为 2 6 8× 10 - 5A·cm- 2 。使用循环伏安曲线和断电后的放电曲线研究熔体中Sm3 +的电化学行为 ,表明Sm3 +难以单独沉积 ,但通过加入Fe2 +可以诱导其共沉积。在Cu基体上进行恒电位和恒电流电解 ,得到Sm含量高于 90 % (质量分数 )的Sm Fe合金膜 ;发现Sm含量与阴极电位、电流密度以及SmCl3 /FeCl2 的摩尔比有关。

关键词：稀土钐离子铁离子 Sm-Fe合金诱导共沉积尿素 NaBr 溴化钠钐铁合金膜低温熔盐电化学行为磁性材料

Identifiability and sloppiness of structured systems with a matrix fraction description using finite frequency responses

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Science China(Information Sciences) 2025年

作者： Yunxiang MA tong ZHOU Department of Automation Tsinghua University Department of Automation and BNRist Tsinghua University

This paper investigates the identifiability of structured systems with a matrix fraction description and attacks practical difficulties in estimating parameters under finite frequency responses. The numerator and denominator polynomial matrices depend affinely on system parameters, which can represent a broad range of systems, especially circuits and mechanical systems. Except for assuming that the denominator matrix is invertible, no further assumptions are adopted. A criterion is provided for validating this assumption utilizing graph theories and matroids. A sufficient and necessary criterion for global identifiability based on the rank of a numerical matrix is given and can be recursively verified with each frequency point,which is computationally attractive for large-scale systems. For an identifiable system, an ellipsoid approximation is obtained for the set of parameters whose corresponding system frequency responses deviate within a specific range from those of the system at a specific parameter value. Using this approximation, explicit expressions for absolute and relative sloppiness have been derived, which can be used to quantify the difficulty of identifying system parameters. Comparisons with the well-known Fisher information matrix have also been performed through a mechanical system, revealing significant differences in quantifying parameter estimation hardness.

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二甲基甲酰胺中钐盐的电导研究

中国稀土学报 2003年第1期21卷 10-14页

作者：王宇刘冠昆陈六平童叶翔中山大学化学与化学工程学院广东广州510275

通过电导测量研究了4种钐盐:Sm(CF3SO3)3,Sm(ClO4)3,Sm(NO3)3,和SmCl3在极性非质子溶剂DMF中的电导性质。利用线性拟合方法求得在25℃下Sm(CF3SO3)3和Sm(ClO4)3的极限摩尔电导率分别为274 5和283 2S·cm2·mol-1。用间接方法求得Sm(NO3)3与SmCl3的极限摩尔电导率分别为299 7,289 8S·cm2·mol-1。在25～65℃温度范围内,Sm(CF3SO3)3和Sm(ClO4)3的电导率随温度呈线性变化。Sm(NO3)3,SmCl3的电导行为表现出明显的离子缔合。

关键词：物理化学钐盐电导率二甲基甲酰胺离子缔合稀土

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钇在二甲基亚砜溶剂中的电化学行为

中国稀土学报 1999年第3期17卷 193-197页

作者：何山刘冠昆童叶翔谷历文蒋卫中吴兰宝中山大学化学与化学工程学院广州510275

研究了ＹＣｌ３ＬｉＣｌＯ４ＤＭＳＯ（二甲基亚砜）体系电导率与温度的关系，及钇在Ｐｔ和Ｃｕ电极上的电化学行为。结果表明，Ｙ３＋在Ｐｔ和Ｃｕ电极上可一步不可逆还原为Ｙ，在铜电极上于－２．５００Ｖ（ｖｓＳ... 详细信息

研究了ＹＣｌ３ＬｉＣｌＯ４ＤＭＳＯ（二甲基亚砜）体系电导率与温度的关系，及钇在Ｐｔ和Ｃｕ电极上的电化学行为。结果表明，Ｙ３＋在Ｐｔ和Ｃｕ电极上可一步不可逆还原为Ｙ，在铜电极上于－２．５００Ｖ（ｖｓＳＣＥ）下恒电位电解，可获得粘附性好、Ｙ含量达９７．９％（质量分数）的均匀沉积膜。利用循环伏安法、计时电流法、计时电位法测定了Ｙ３＋离子在２９８Ｋ下，ＹＣｌ３ＬｉＣｌＯ４ＤＭＳＯ溶液中的扩散系数为３．２２ ×１０－６ｃｍ２·ｓ－１，电荷传递系数为０．２２。

关键词：稀土钇电沉积二甲基亚砜电镀溶剂电化学

Poly(lactic acid)/Poly(butylene adipate-co-terephthalate)films with simultaneous high oxygen barrier and fast degradation properties

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Green Energy & Environment 2025年第1期10卷 1-10页

作者： Mengjing Yang Yuxi Mao Penghui Zhang Jie Li Zeming tong Zhenguo Liu Yanhui Chen Institute of Flexible Electronics Northwestern Polytechnical UniversityXi'an710072China Key Laboratory of Flexible Electronics of Zhejiang Province Ningbo Institute of Northwestern Polytechnical University218 Qingyi RoadNingbo315103China School of Chemistry and Chemical Engineering Shaanxi Key Laboratory of Macromolecular Science and TechnologyKey Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi'an 710072China

Although poly(lactic acid)(PLA)is a good environmentally-friendly bio-degradable polymer which is used to substitute traditional petrochemical-based polymer packaging films,the barrier properties of PLA films are still insufficient for high-barrier packaging *** this study,oxygen scavenger hydroxyl-terminated polybutadiene(HTPB)and cobalt salt catalyst were incorporated into the PLA/poly(butylene adipate-co-terephthalate)(PLA/PBAT),followed by melting extrusion and three-layer co-extrusion blown film process to prepare the composite *** oxygen permeability coefficient of the composite film combined with 6 wt%oxygen scavenger and 0.4 wt%catalyst was decreased significantly from 377.00 cc·mil·m^(-2)·day^(-1)·0.1 MPa^(-1) to 0.98 cc·mil·m^(-2)·day^(-1)·0.1 MPa^(-1),showing a remarkable enhancement of 384.69 times compared with the PLA/PBAT composite ***,the degradation behavior of the composite film was also accelerated,exhibiting a mass loss of nearly 60%of the original mass after seven days of degradation in an alkaline environment,whereas PLA/PBAT composite film only showed a mass loss of 32%.This work has successfully prepared PLA/PBAT composite films with simultaneously improved oxygen barrier property and degradation behavior,which has great potential for high-demanding green chemistry packaging industries,including food,agricultural,and military packaging.

关键词： Barrier property Oxygen scavenging Blow molding Eco-packaging Degradable composite film

Marine dispersion of Fukushima-derived radiocesium in the North Pacific and its implications

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Science China Earth Sciences 2025年

作者： tong ZHANG Xiaolin HOU Yukun FAN State Key Laboratory of Loess and Quaternary Geology Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application Xi'an AMS Center Institute of Earth Environment Chinese Academy of Sciences University of Chinese Academy of Sciences Xi'an Institute for Innovative Earth Environment Research

A key scientific approach to addressing the environmental radiation risks from Fukushima nuclear contaminated water （FNCW） discharge into the ocean is understanding and predicting the marine dispersion of *** dispersion of radiocesium (CsF:134Cs,137Cs) from the Fukushima nuclear accident in the North Pacific and its marginal seas post-2011 was systematically summarized,focusing on pathways,vertical distribution changes,and transit *** research examined CsFdispersion through the Kuroshio Extension and denser central mode water （D-CMW） to the eastern North Pacific,as well as through subtropical mode water （STMW）,lighter central mode water （L-CMW）,and D-CMW to the subtropical western North Pacific,China Seas,and Sea of *** considered broader implications of CsFdispersion in light of ongoing FNCW *** this prolonged liquid discharge and Kuroshio Extension’s barrier effect,it is crucial to emphasize the role of CMW besides STMW in transporting FNCW to the subtropical western North Pacific and its marginal *** research should focus on the key mechanism and longitude range of CMW crossing the Kuroshio *** short-lived134Cs decays rapidly during the storage and dispersion of FNCW,long-lived135Cs and135Cs/137Cs ratios can serve as valuable tracers for detecting and quantifying ***,there is an urgent need for high-precision analysis of these key radionuclides and their characteristic *** promptly detect,assess,and respond to FNCW intrusion,continuous monitoring and identification of nuclear pollution sources in key ocean currents and straits are ***,interdisciplinary research integrating monitoring with marginal sea circulation dynamics and high-resolution numerical simulations should be a priority

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非水溶剂中电沉积制备稀土合金膜

稀土 1998年第3期19卷 49-56页

作者：谷历文刘冠昆杨绮琴童叶翔刘建平中山大学化学与化工学院

稀土合金作为高温超导、永磁和磁光记录材料等颇受人们关注。如果采用电沉积的方法制备，则可大大改进它们的功能效果和扩展应用领域。本文着重综述了从非水介质中电沉积稀土元素及其合金膜的进展。

关键词：电沉积非水溶剂稀土合金膜制备