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非开挖修复技术在截污管道修复中的应用

城市道桥与防洪 2024年第6期 212-214,218页

作者：赵士雄杨元元宋清泉北京市市政专业设计院股份公司北京市100037 鄂尔多斯市环保投资有限公司内蒙古鄂尔多斯017000 中设建联工程设计有限公司广东珠海519000

截污治污工程作为水质改善的重要组成部分,对水环境治理具有基础性作用。很多城市的截污管道由于建成年代早、使用年限长,已出现不同程度的缺陷,污水外渗严重影响周边河流与地下水环境。非开挖修复技术凭借施工占地少、工期短、环境效... 详细信息

截污治污工程作为水质改善的重要组成部分,对水环境治理具有基础性作用。很多城市的截污管道由于建成年代早、使用年限长,已出现不同程度的缺陷,污水外渗严重影响周边河流与地下水环境。非开挖修复技术凭借施工占地少、工期短、环境效益好等优势,在截污管道修复中得到广泛应用。结合广东省惠州市某截污管道修复工程,对非开挖修复技术的选择与应用进行探讨,为同类工程提供参考。

关键词：截污管道非开挖修复原位固化

Atmospheric Drying UHMWPE Membranes via Multiple Stage Extractant Exchange Drying Technique

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Advanced Fiber Materials 2022年第2期4卷 235-245页

作者： Jiayou Quan qingquan song Junrong Yu Yan Wang Jing Zhu Zuming Hu State Key Laboratory for Modifcation of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China

Ultra-high molecular weight polyethylene(UHMWPE)membranes were prepared by 5 wt%UHMWPE/parafn oil gels via thermally induced phase separation method and dried in air without signifcant *** UHMWPE membranes were annealed at 110℃ for increasing the pores size in order to decrease the capillary ***,a new multiple stage extractant exchange drying(MSEED)technique was adopted to decrease the shrinkage of the UHMWPE ***,the parafn oil was extracted by dichloromethane,then dichloromethane was replaced by ethanol,next ethanol could be exchanged to other liquid which is non-afnity with UHMWPE,for example *** membranes(annealing for 25 min)dried by dichloromethane-ethanol-water-air process have the lowest volume shrinkage of 16.5%and the porosity is as high as 88.29%.Moreover,compared with supercritical CO_(2)(SC-CO_(2))drying,atmospheric drying UHMWPE membranes have a lower pure water permeance,but a higher carbon particles rejection.

关键词： UHMWPE Atmospheric drying Supercritical CO_(2)drying Multiple stage extractant exchange drying technique

The Structure and Properties of Polyethylene Oxide Reinforced Poly(Metaphenylene Isophthalamide)Fibers

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Advanced Fiber Materials 2022年第3期4卷 436-447页

作者： qingquan song Wenwen Wu Yi Wang Junrong Yu Zuming Hu Yan Wang State Key Laboratory for Modifcation of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620People’s Republic of China

In this paper,the efect of poly(ethylene oxide)(PEO)as an additive on the structure and properties of poly(m-phenylene dimethylene terephthalamide)(PMIA)fbers obtained by wet spinning was *** tensile strength of the composite fbers was substantially enhanced compared to the pure PMIA *** was due to the fact that the addition of PEO weakens the hydrogen bonding between PMIA molecular chains resulting in an improved orientation of the composite *** was found that the optimum PEO addition was 2%and the tensile strength of the composite fber was 4.74 cN/dtex,which was 76%higher compared to the pure PMIA ***,the heat resistance and fame retardancy of the composite fbers were basically unchanged compared to the pure PMIA *** modifcation method is simple,with low raw material cost and good stability,and has not only good academic value but also excellent industrial value.

关键词： Poly(metaphenylene isophthalamide) Polyethylene oxide Mechanical properties Hydrogen bonding

Dissolving of Ultra‑high Molecular Weight Polyethylene Assisted Through Supercritical Carbon Dioxide to Enhance the Mechanical Properties of Fibers

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Advanced Fiber Materials 2022年第2期4卷 280-292页

作者： Yi Wang Jiabin Fu Junrong Yu qingquan song Jing Zhu Yan Wang Zuming Hu State Key Laboratory for Modifcation of Chemical Fibers and Polymer Materials College of Material Science and EngineeringDonghua UniversityShanghai 201620China

The molecular weight of ultra-high molecular weight polyethylene(UHMWPE)fbers is severely decreased compared with raw materials due to high temperature and strong shearing in the dissolving *** this study,we reported a novel method to assist the dissolving of UHMWPE in parafn oil without severe degradation in order to improve the tensile strength of resultant *** fbers with relatively high molecular weight and more excellent disentanglement efect were prepared by gel-spinning with UHMWPE suspension treated with supercritical carbon dioxide(SC-CO_(2)).The dynamic thermomechanical,mechanical and crystalline properties of UHMWPE extracted fbers and drawn fbers were researched *** extracted fbers obtained after SC-CO_(2) treatment display a higher molecular *** importantly,it is clear that the disentanglement of UHMWPE gel fbers gained by processing SC-CO_(2) has been signifcantly promoted compared with that without SC-CO_(2) treatment from dynamic thermomechanical and rheological results,which could also be demonstrated from the cross-sectional morphology of UHMWPE extracted ***,the tensile strength of UHMWPE fbers prepared through SC-CO_(2) treating is able to attain 30.11 cN/dtex,increased by 10.3%in comparison to UHMWPE fbers gained without assistance of SC-CO_(2).Beyond that,the thermal behavior and crystallization performance of UHMWPE extracted fbers and drawn fbers acquired by way of SC-CO_(2) treatment have also been enhanced.

关键词： Ultra-high molecular weight polyethylene fbers Supercritical carbon dioxide Tensile strength Chain entanglement Molecular degradation Gel-spinning

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与算子相连的面积积分在乘积空间中的有界性

中国科学：数学 2024年第1期54卷 59-74页

作者：宋娟邓清泉湖北经济学院统计与数学学院武汉430205 湖北经济学院大数据与数字经济研究院武汉430205 华中师范大学数学与统计学学院武汉430079

本文假设自伴算子L_(1)与L_(2)的热半群满足非对角估计(GGE_(p0)),其中p_(0)∈[1,2).在乘积空间R^(n_(1))×R^(n_(2))中,本文通过自伴算子L_(1)与L_(2)的热半群定义了与算子相连的面积积分S,证明了当p∈(p0,p’0)时,面积积分S在L^(p)(R^... 详细信息

本文假设自伴算子L_(1)与L_(2)的热半群满足非对角估计(GGE_(p0)),其中p_(0)∈[1,2).在乘积空间R^(n_(1))×R^(n_(2))中,本文通过自伴算子L_(1)与L_(2)的热半群定义了与算子相连的面积积分S,证明了当p∈(p0,p’0)时,面积积分S在L^(p)(R^(n_(1))×R^(n_(2)))中的有界性.

关键词：面积积分乘积空间非对角估计

The Persistence and Zonal Scale of Atmospheric Dipolar Modes

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Advances in Atmospheric Sciences 2024年第3期41卷 478-492页

作者： Jie song State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China

This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(DMs). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model show that the atmospheric DMs with a broader(narrower) zonal scale dipolar structure possess a longer(shorter) persistence. A detailed vorticity budget analysis indicates that the persistence of a hemispheric-scale DM(1/1 DM) and a regional or sectoral DM(1/8 DM) in the model both largely rely on the persistence of the nonlinear eddy forcing. Linear terms can indirectly reduce the persistence of the anomalous nonlinear eddy forcing in a 1/8 DM by modifying the baroclinicity via the arousal of anomalous vertical motions. Therefore, the atmospheric DMs with a broader(narrower) zonal scale possess a longer(shorter) persistence because the effects of the linear terms are less(more) pronounced when the atmospheric DMs have better(worse) zonal symmetry. Further analyses show that the positive eddy feedback effect is weak or even absent in a 1/8DM and the high-frequency eddy forcing acts more like a concomitant phenomenon rather than a leading driving factor for a 1/8 DM. Thus, the hemispheric-scale DM and the regional or sectoral DMs are different, not only in their persistence but also in their dynamics.

关键词： NAM NAO eddy feedback persistence linear term

Identification of Linear Systems Using Binary Sensors with Random Thresholds

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Journal of Systems Science & Complexity 2024年第3期37卷 907-923页

作者： HUANG Zhiyong song Qijiang School of Mathematics Renmin University of ChinaBeijing 100872China School of Mathematics Sino-French InstituteRenmin University of ChinaBeijing 100872China

In this paper,the problem of identifying autoregressive-moving-average systems under random threshold binary-valued output measurements is *** the help of stochastic approximation algorithms with expanding truncations,the authors give the recursive estimates for the parameters of both the linear system and the binary *** reasonable conditions,all constructed estimates are proved to be convergent to the true values with probability one,and the convergence rates are also established.A simulation example is provided to justify the theoretical results.

关键词： α-mixing binary sensor quantized system stochastic approximation stochastic thresh-old strongly consistent system identification

Chemical vapor deposition making better lithium-sulfur batteries

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Science Bulletin 2024年第13期69卷 2013-2016页

作者： Yingze song Lixian song Menglei Wang Wenlong Cai State Key Laboratory of Environment-Friendly Energy Materials School of Materials and ChemistrySouthwest University of Science and TechnologyMianyang 621010China School of Material Science and Engineering Henan University of TechnologyZhengzhou 450001China Department of Advanced Energy Materials College of Materials Science and EngineeringSichuan UniversityChengdu 610064China

The burgeoning demand for modern electronic devices and electric vehicles has driven the development of efficient,reliable,and environmentally friendly batteries[1,2].Lithium–sulfur(Li–S)batteries with high theoretical capacity(1672 mA h g1)and energy density(2600 W h kg1),have garnered significant interest in both academic and industrial research[3,4].However,the widespread production and commercialization of Li–S batteries are impeded by the inherent characteristics of sulfur and lithium,along with their complex electrochemical ***,challenges such as the polysulfide shuttle effect and the slow kinetics of the sulfur nucleation/decomposition reaction hinder capacity utilization and cycling *** overcome these challenges,innovative electrocatalyst strategies aimed at enhancing activity have been explored.

关键词： lithium overcome cycling

Self-healing Ga-based liquid metal/alloy anodes for rechargeable batteries

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Nano Research 2024年第3期17卷 1366-1383页

作者： Meijia song Zhonghua Zhang School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212000China Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJingshi Road 17923Jinan 250061China

With the rapid development of electronics,electric vehicles,and grid energy storage stations,higher requirements have been put forward for advanced secondary *** metal/alloy electrodes have been considered as a promising development direction to achieve excellent electrochemical performance in metal-ion batteries,due to their specific advantages including the excellent electrode kinetics and self-healing ability against microstructural electrode *** conventional liquid batteries,high temperatures are needed to keep electrode liquid and ensure the high conductivity of molten salt electrolytes,which also brings the corrosion and safety ***-based metal/alloys,which can be operated at or near room temperature,are potential candidates to circumvent the above *** this review,the properties and advantages of Ga-based metal/alloys are ***,Ga-based liquid metal/alloys as anodes in various metal-ion batteries are reviewed in terms of their self-healing ability,battery configurations,working mechanisms,and so ***,some views on the future development of Ga-based electrodes in batteries are provided.

关键词： metal-ion batteries Ga-based liquid metal/alloy anodes self-healing capability room temperature