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An equivalent 1D nanochannel model to describe ion transport in multilayered graphene membranes

Progress in Natural Science:Materials International 2018年第2期28卷 246-250页

作者： Gengping Jiang peiyao wang Chi Cheng Dan Li Jefferson Zhe Liu College of Science Wuhan University of Science and Technology Department of Materials Science and Engineering Monash University Department of Mechanical Engineering The University of Melbourne 4. Department of Chemical Engineering The University of Melbourne Department of Mechanical and Aerospace Engineering Monash University

Multilayered graphene-based membranes are promising for a variety of applications related to ion or molecule transport, such as energy storage and water treatment. However, the complex three-dimensional cascading nanoslit-like structure embedded in the membrane makes it difficult to interpret and rationalize experimental results, quantitatively compare with the traditional membrane systems, and quantitatively design new membrane structures. In this paper, systematic numerical simulations were performed to establish an equivalent onedimensional(1 D) nanochannel model to represent the structure of multilayered graphene membranes. We have established a quantitative relationship between effective diffusion length Leffand cross-section area Aeffof the1 D model and our recently developed two dimensional(2 D) representative microstructure for graphene membranes. We find that only in the cases of a relatively large lateral size L(> ~100 nm) and a small slit size h(< 2 nm), the effective diffusion length Leffand Aeffcan be calculated by an over-simplified but often used model. Otherwise, they show complex dependence on all three structural parameters of the 2 D structural *** equivalent 1 D nano-channel model can reproduce experimental results very well except for h < 0.5 nm. The discrepancy could be attributed to the anomalous behaviour of molecules under nano-confinement that is not considered in our simulations. This model can also be extended to multilayered membranes assembled by other2 D materials.

关键词： Graphene 2D materials Equivalent 1D nanochannel Time-lag method Continuum modelling

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Novel Method to Graft Chitosan on the Surface of Hydroxyapatite Nanoparticles via ＂Click＂ Reaction

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Chemical Research in Chinese Universities 2014年第6期30卷 1063-1065页

作者： WEI Junchao GUO-wang peiyao CUI Liguo ZHANG Haobin DAI Yanfeng LIU Tianxi Department of Chemistry Nanehang University Nanchang 330031 P. R. China State Key Laboratory of Molecular Engineering of Polymers Department of Maeromolecular Science Fudan University Shanghai 200433 P. R. China Key Laboratory of Polymer Ecomaterials Changehun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China

In order to tune the surface properties of hydroxyapatite（HA） nanoparticles and prevent them from ag- gregation, an efficient method was proposed to graft chitosan（CS） molecules on the surface of HA via ＂click＂ reac- tion. Thermal gravimetric analysis（TGA） shows that CS was successfully grafted on the surface of HA nanoparticles and the grafting amount was about 8.9 g of CS on per hundred grams of HA. The grafted chitosan chains can prevent HA nanoparticles from aggregation and greatly enhance the colloidal stability of HA in water. The 3-（4,5-dimethylthiazoyl-2-yl）-2,5-diphenyltetrazolium bromide（MTT） assay demonstrats that the cytotoxicity of CS modified HA（HA-CS） is negligible and thus HA-CS may find potential application in biomedical fields.

关键词： Hydroxyapatite Chitosan Surface modification Nanocomposite Biomaterial

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Foam Forming: An Effective Method to Prepare Polyimide Fiber-based Paper

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Paper And Biomaterials 2019年第3期4卷 39-44页

作者： Shunxi Song Xiaoli Zhen Meiyun Zhang peiyao wang Jiaojun Tan National Demonstration Center for Experimental Light Chemistry Engineering Education Shaanxi Provincial Key Laboratory of Papermaking Technology and Specialty Paper Development Key Laboratory of Paper Based Functional Materials of China National Light Industry College of Bioresources Chemical and Materials Engineering Shaanxi University of Science & Technology

Well-dispersed fiber suspension is the precondition of good paper formation. Compared with cellulosic fibers, synthetic fibers are prone to flocculate because of their long length and hydrophobic nature, resulting in poor paper formation. To solve this problem, dispersants and extremely low forming consistency are typically adopted during the traditional wet-forming process, which cause a large amount of water consumption and treatment cost. Therefore, increasing forming consistency without compromising paper formation remains a challenge for papermakers. In this work, foam forming was adopted to disperse polyimide fibers (PI) with high forming consistency. The results showed that the formation index of handsheets increased when the bubble size and distribution became small and narrow. Compared with traditional wet-forming process with the same consistency (0.4%), the formation index of handsheets by foam forming increased by approximately 100% when C8 alkyl glucoside (APG08) concentration reached 16 g/L. Notably, forming consistency could increase by eight times while keeping the same level of paper formation. Overall, foam forming exhibits great advantages in dispersing long fiber and reducing water consumption and environmental pressure, and has potential applications in specialty paper made of long fibers.

关键词： foam forming long PI fibers high forming consistency bubble size formation

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Carbon-supported and nanosheet-assembled vanadium oxide microspheres for stable lithium-ion battery anodes

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Nano Research 2016年第1期9卷 128-138页

作者： Chaojiang Niu Meng Huang peiyao wang Jiashen Meng Xiong Liu Xuanpeng wang Kangning Zhao Yang Yu Yuzhu Wu Chao Lin Liqiang Mai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan430070 China

Naturally abundant transition metal oxides with high theoretical capacity have attracted more attention than commercial graphite for use as anodes in lithium-ion batteries. Lithium-ion battery electrodes that exhibit excellent electrochemical performance can be efficiently achieved via three-dimensional （3D） architectures decorated with conductive polymers and carbon. As such, we developed 3D carbon-supported amorphous vanadium oxide microspheres and crystalline V203 microspheres via a facile solvothermal method. Both samples were assembled with ultrathin nanosheets, which consisted of uniformly distributed vanadium oxides and carbon. The formation processes were clearly revealed through a series of time-dependent experiments. These microspheres have numerous active reaction sites, high electronic conductivity, and excellent structural stability, which are all far superior to those of other lithium-ion battery anodes. More importantly, 95% of the second-cycle discharge capacity was retained after the amorphous microspheres were subjected to 7,000 cycles at a high rate of 2,000 mA/g. The crystalline microspheres also exhibited a high-rate and long-life performance, as evidenced by a 98% retention of the second-cycle discharge capacity after 9,000 cycles at a rate of 2,000 mA/g. Therefore, this facile solvothermal method as well as unique carbon-supported and nanosheet-assembled microspheres have significant potential for the synthesis of and use in, respectively, lithium-ion batteries.

关键词： vanadium oxide microspheres amorphous lithium-ion battery anodes

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Interaction between PCC Filler and Cellulosic Fiber in Fiber/Filler Co-refining System

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Paper And Biomaterials 2021年第4期6卷 30-37页

作者： Sheng Qiang Shunxi Song peiyao wang Yujie Shi Linhao Li Haitang Liu College of Bioresources Chemical and Materials Engineering National Demonstration Center for Experimental Light Chemistry Engineering Education(Shaanxi University of Science&Technology)Shaanxi University of Science and TechnologyXi'anShaanxi Province710021China Tianjin Key Laboratory of Pulp&Paper Tianjin University of Science&TechnologyTianjin300457China

Mineral fillers are important for conserving raw fiber materials and reducing production costs in the paper ***,the increase in filler content will inevitably result in strength reduction,which limits the adding amount of filler in paper *** this study,we designed a cellulose fiber/filler co-refining approach to improve the strength and optical properties of paper;moreover,the synergistic interaction between fibers and precipitated calcium carbonate(PCC)fillers in the co-refining process was *** of fiber separation and PCC particle size analysis showed that,compared with conventional refining,the content of fines increased,whereas the PCC particle size *** importantly,composites were formed between the PCC and fines,which promoted strength improvement of *** tests show that the tensile index of paper with 15%PCC content increased by 22%compared with that of the paper filled by conventional method,whereas the brightness and opacity of paper improved by fiber/filler co-refining for a specified filler *** findings provide a basis for the further development of co-refining filling technology.

关键词： cellulosic fiber mineral filler filler composite paper strength optical properties

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炒制对燕麦粉风味特性及面团形成的影响

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中国食品学报 2024年第7期24卷 269-277页

作者：王佩瑶张美莉内蒙古农业大学食品科学与工程学院呼和浩特010018

研究炒制对燕麦粉的风味特性及面团特性的影响。燕麦粉按炒制程度分为生燕麦粉、半熟燕麦粉和熟燕麦粉。采用电子鼻测定其风味成分,采用主成分分析等方法综合判断不同处理方式的燕麦面团的风味特性,研究不同炒制程度以及和面水温度条件... 详细信息

研究炒制对燕麦粉的风味特性及面团特性的影响。燕麦粉按炒制程度分为生燕麦粉、半熟燕麦粉和熟燕麦粉。采用电子鼻测定其风味成分,采用主成分分析等方法综合判断不同处理方式的燕麦面团的风味特性,研究不同炒制程度以及和面水温度条件下燕麦面团的理化特性。结果表明,随着炒制程度的增强,燕麦粉直链淀粉含量显著升高(P<0.05),溶解度和膨胀度随时间的延长呈先增加后减少的趋势;炒制后的燕麦粉的起始温度降至60.07℃,峰值温度和热焓值逐渐降低,且炒制未改变燕麦淀粉的晶型结构。扫描电镜图显示熟制燕麦粉的淀粉颗粒表面有更多的凹陷,随着和面水温度的升高,面团黏聚性增加。炒熟后的样品以及用100℃水和面的面团,其醛类物质及烷烃类芳香成分显著增加。研究表明炒熟的燕麦粉加工性能最优,面团风味和面团理化特性最佳。

关键词：燕麦炒制程度理化性质风味特性面团特性

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多网融合下的市域铁路列车控制系统方案研究

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城市轨道交通研究 2022年第11期25卷 53-56页

作者：王珮瑶中铁二院工程集团有限责任公司成都610031

目前能够兼容CTCS(中国列车运行控制系统)和CBTC(基于通信的列车控制)的信号系统正在研发中。信号系统能否实现互联互通,已成为多网融合下列车在不同信号制式轨道交通线路上混跑的重中之重。以CTCS和CBTC为研究对象,分析两者的技术特点... 详细信息

目前能够兼容CTCS(中国列车运行控制系统)和CBTC(基于通信的列车控制)的信号系统正在研发中。信号系统能否实现互联互通,已成为多网融合下列车在不同信号制式轨道交通线路上混跑的重中之重。以CTCS和CBTC为研究对象,分析两者的技术特点和兼容可行性,研究了市域铁路列车控制系统选型的各种可能性方案。针对CBTC和CTCS两种信号制式,提出了双车载设备方案和一体化车载设备方案,并对两个车载设备方案进行了优缺点分析,以期为多网融合下市域铁路信号系统的互联互通性设计提供参考。

关键词：市域铁路列车控制系统兼容性信号系统互联互通多网融合

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基于Zipf定律的随机森林财务预警模型

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山西大学学报(自然科学版) 2023年第4期46卷 821-829页

作者：孟银凤王珮瑶山西大学数学科学学院

为了有效识别财务报表欺诈，解决现有欺诈检测模型应用局限性问题，并对上市公司财务危机做出准确预测，提出了一个基于Zipf定律的随机森林财务预警模型。首先，对财务数据集进行特征选择，运用随机森林算法计算特征变量重要性，筛选后... 详细信息

为了有效识别财务报表欺诈，解决现有欺诈检测模型应用局限性问题，并对上市公司财务危机做出准确预测，提出了一个基于Zipf定律的随机森林财务预警模型。首先，对财务数据集进行特征选择，运用随机森林算法计算特征变量重要性，筛选后得到用于分类检测的最优特征子集；其次，通过构造Zipf因子，生成新的特征向量补充到数据集中以挖掘更多有效信息，并将其与随机森林模型结合，识别具有财务欺诈风险的样例，得到分类预测结果；最后，基于1997—2017年中国A股上市公司的财务数据进行100次重复实验，以AUC值、准确率、召回率、特异度等指标对模型进行评价，并对比该模型与其他几种预警模型的预测性能，结果表明，基于Zipf定律的随机森林模型对上市公司财务风险的预测效果更优。

关键词： Zipf定律财务预警随机森林财务欺诈预测性能

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《公无渡河》诗题在唐宋嬗变之浅析

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乐山师范学院学报 2020年第2期35卷 20-25页

作者：王培瑶兰州大学文学院

《公无渡河》是汉乐府诗歌中的一个重要主题,历代诗人多有模拟,或重述其题,繁饰华缛以呈技炫才;或引申其义,悲歌慷慨以抒解情怀;或寄寓诗题,持重说理以陈情达意。千余年来,作为凝结着传统诗歌风骚精神的《公无渡河》,传达出的悲壮情感... 详细信息

《公无渡河》是汉乐府诗歌中的一个重要主题,历代诗人多有模拟,或重述其题,繁饰华缛以呈技炫才;或引申其义,悲歌慷慨以抒解情怀;或寄寓诗题,持重说理以陈情达意。千余年来,作为凝结着传统诗歌风骚精神的《公无渡河》,传达出的悲壮情感和抗争精神,滋育了之后的众多诗人。通过探赜唐宋这一诗题中所渗透的不尽之意,可以看到故事原型被赋予渐趋固定的象喻意义,原本的乐府诗题逐渐走向政治化、文人化。

关键词：《公无渡河》诗题嬗变政治化文人化

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碱性过氧化氢处理对藕渣可溶性膳食纤维结构及流变学特性的影响

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中国食品学报 2024年第5期24卷 245-253页

作者：徐磊张倩王佩瑶王子成黄琳茜何玲淮阴工学院生命科学与食品工程学院江苏淮安223003

以藕渣作为主要原料,采用碱性过氧化氢(AHP)处理后提取可溶性膳食纤维(SDF),比较处理前、后所得藕渣SDF结构和流变学特性的变化。结果表明:经AHP处理后,藕渣SDF提取率提高了7.21倍(P<0.05),单糖组成分析表明其L-鼠李糖和D-半乳糖含量分... 详细信息

以藕渣作为主要原料,采用碱性过氧化氢(AHP)处理后提取可溶性膳食纤维(SDF),比较处理前、后所得藕渣SDF结构和流变学特性的变化。结果表明:经AHP处理后,藕渣SDF提取率提高了7.21倍(P<0.05),单糖组成分析表明其L-鼠李糖和D-半乳糖含量分别增加了51.85%和39.27%(P<0.05)。与未处理藕渣的SDF相比,AHP处理后藕渣SDF的分子质量减小,Zeta-电位从-24.80 mV降至-26.95 mV(P<0.05)。扫描电子显微镜、傅里叶变化光谱分析表明:AHP处理藕渣的SDF结构变得蓬松,表面变得粗糙,部分特征官能团发生变化。X-射线衍射、热重分析表明:经AHP处理的藕渣SDF结晶度降低,而其高温热稳定性提高。稳态、动态流变学分析表明:在Ca2+存在下AHP处理藕渣的SDF表现出更高的剪切黏度和更强的凝胶化能力。结论:AHP处理藕渣能改善所得SDF的结构及流变学特性,可为藕渣的开发利用提供一定的参考。

关键词：碱性过氧化氢藕渣可溶性膳食纤维结构流变学特性

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