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Paper And Biomaterials 2022年第3期7卷 19-29页

作者： xiaorui jin Mingguo Ma Jun Yang Beijing Key Laboratory of Lignocellulosic Chemistry College of Materials Science and TechnologyBeijing Forestry UniversityBeijing100083China

The rheological characteristics of a physical gelation system,in which cellulose nanocrystals(CNC_(s))induced the entanglement of poly(acrylic acid)(PAA)chains and partial hydrophobic association of octylphenol polyoxyethylene acrylate(OP-10-AC)branches in a micellar solution of sodium dodecyl sulfate(SDS),were *** gelation time of the physical gels decreased as the CNC content and number of hydrophobic branch units *** the gel point,the storage modulus(G')and loss modulus(G")followed the same frequency dependence(G'≈G"≈ωn),where the hydrophobic moieties attached to the side chains had a significant impact on the values of viscoelastic exponent(n).Beyond the gel point,the initial polymer solution was transformed to a solid-like gel,and the strength of the gel network was governed by associations between both the CNCs and hydrophobic *** evolution of the viscoelasticity during the gel-sol transition was monitored,demonstrating that due to a reversible arrangement of the hydrophobic units,a large proportion of physical cross-links dissociated under a thermal trigger and were reversibly reformed when the solution was cooled,while no such partial recovery was observed in the case of the single CNC-induced network systems(with no hydrophobic branches).

关键词： hydrogels cellulose nanocrystals hydrophobic association rheology

1D/2D composite subnanometer channels for ion transport:The role of confined water

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Nano Research 2023年第8期16卷 10913-10921页

作者： Yuhao Li xiaorui jin Xinhai Yan Xinyu Ai Xin Yang Zi-Jian Zheng Kun Huang Gaofeng Zhao Yongan Yang Meiling Wu Kai-Ge Zhou Institute of Molecular Plus Department of ChemistryTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials Hubei Key Laboratory of Polymer MaterialsHubei UniversityWuhan 430062China School of Chemical Engineering and Analytical Science National Graphene InstituteUniversity of ManchesterManchesterM139PLUK School of Civil Engineering Tianjin UniversityTianjin 300072China

As a mass transport media,water is an alternative of organic solvent applied in rechargeable batteries,due to its unique properties,including fast ionic migration,easy-processibility,economic/environmental friendliness,and flame ***,due to the high activity of water molecules in aqueous electrolytes,the corrosion of metal anode,side reactions,and inferior metal electrodeposition behavior leads to unstable cycling performance,poor Coulombic efficiency(CE),and early-staged failure of *** several attempts to regulate the activity of water,migration of ions is sacrificed,due to the limited methods to control the water ***,we developed a subnanoscale confinement strategy based on a nacre-like structure to modulate the activity of water in the solid *** tuning the ratio between the two-dimensional(2D)vermiculite and one-dimensional(1D)cellulose nanofibers(CNFs),the capillary size in the 1D/2D structure is altered to achieve a fast Zn^(2+)*** dielectric relaxation and molecular dynamics studies indicate that the enhanced Zn^(2+)conductivity is attributed to the fast water relaxation in the precisely defined 1D/2D *** advantage of the regulated activity of the confined water in 2D capillary,the composite vermiculite membrane can suppress the corrosion and side reactions between Zn electrode and water molecular,endowing a reversible Zn^(2+)stripping/plating behavior and a stable cycling performance for 900 *** on our confinement strategy to control the water states by 1D/2D structures,this work will open an avenue toward aqueous energy storage devices with excellent reversibility,high safety,and long-term stability.

关键词： ion transport subnanometer channels confined water aqueous electrolyte limited side reactions

Study on the Effectiveness of Circulation Well for Remediation of Benzene and Toluene Contaminated Silt Sand Aquifer

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Journal of Environmental Science and Engineering(B) 2024年第4期13卷 125-133页

作者： Zhiqiang Gong xiaorui jin Xiaoxi Zhang Jiangwei Shang Yiwen Zhou Wei Du Biao Yu Hebei Geological Environment Monitoring Institute Shijiazhuang 050021China Hebei Key Laboratory of Geological Resources and Environment Monitoring and Protection Shijiazhuang 050021China Suzhou Qianxing Environmental Engineering Co. LtdSuzhou 215000China Institute of Disaster Prevention Sanhe 065201China Hebei Key Laboratory of Resource and Environmental Disaster Mechanism and Risk Monitoring Sanhe 065201China Beijing Disaster Prevention Technology Co. LtdBeijing 101199China School of Ecology and Environment Institute of Disaster PreventionLangfangHebei 065201China

In order to investigate the remediation effect of groundwater circulation well on benzene and toluene contaminated silt sand aquifer,a simulation remediation experiment was conducted in the laboratory using a two-dimensional simulation *** results showed that in the silt sand aquifer,the concentrations of benzene and toluene decreased from 179.210 mg/L and 327.520 mg/L to below the detection limit after 24 h of operation of the circulation *** closer to the circulation well in the horizontal direction,the faster the removal efficiency of benzene and *** study has shown that circulating wells have good remediation effects on both benzene-and toluene-contaminated chalk sand aquifers.

关键词： Groundwater circulation well benzene toluene

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多谱段相机红外光学系统杂散辐射分析

红外与激光工程 2013年第12期42卷 3201-3206页

作者：刘鑫黄一帆李林靳晓瑞北京理工大学光电学院北京100081

杂散辐射是影响多谱段红外相机成像性能的主要因素。为了确保系统在各种工作状况下正常运行,需要分析并抑制相机光学系统中的杂散辐射。在详细分析了其红外光学系统中杂散辐射主要来源的基础上,针对系统特殊的光机结构,在杂光分析软件... 详细信息

杂散辐射是影响多谱段红外相机成像性能的主要因素。为了确保系统在各种工作状况下正常运行,需要分析并抑制相机光学系统中的杂散辐射。在详细分析了其红外光学系统中杂散辐射主要来源的基础上,针对系统特殊的光机结构,在杂光分析软件中建立光机系统模型;围绕遮光罩选取了8个太阳方位、16个离轴角进行光线追迹,得到太阳杂光在像面上产生的辐照度,据此来评价系统杂散辐射水平;同时分析了指向镜滚动轴和俯仰轴在两个方位内的转动以及地球大气杂散辐射对像面辐照度的影响。最后,对于影响严重的杂散辐射,进行了有效的抑制措施。结果表明,可以忽略地球大气的杂散辐射,当太阳杂光入射角大于58°时,系统能满足对像面辐照度的技术要求,多谱段相机红外光学系统可在此范围内正常工作。

关键词：杂散辐射多谱段相机红外光学系统辐照度

游戏活动中促进幼儿深度学习的支持性策略研究

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当代家庭教育 2022年第25期 82-84页

作者：金小芮江苏省南通市开发区中兴幼儿园

游戏是开展幼儿教育的主要方式。在以往教幼儿玩游戏时,教师主导了游戏的方式和主题,幼儿只会被动地参与,在游戏中学习和遵守老师制定的游戏规则。因此,幼儿的学习也只停留在表面,无法深度学习。深度学习不同于机械表面学习,它的特点是... 详细信息

游戏是开展幼儿教育的主要方式。在以往教幼儿玩游戏时,教师主导了游戏的方式和主题,幼儿只会被动地参与,在游戏中学习和遵守老师制定的游戏规则。因此,幼儿的学习也只停留在表面,无法深度学习。深度学习不同于机械表面学习,它的特点是发展高阶思维,旨在提高幼儿分析和解决问题的思维能力。本文阐述了游戏活动对于幼儿深度学习的价值,分析了目前幼儿游戏活动中存在的问题,并对游戏活动中促进幼儿深度学习的支持性策略加以研究,以期有效地促进幼儿通过游戏进行深度学习。

关键词：游戏活动支持性策略幼儿深度学习

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基于无尘纸的复合材料研究进展

天津造纸 2021年第1期43卷 1-5页

作者：靳晓瑞马畅杨俊马明国北京林业大学材料科学与技术学院北京100083

无尘纸由纤维素纤维和聚酯组成,孔隙发达,具有优异的机械性能、耐折性和透气性。以无尘纸为载体制备功能复合材料,可以利用无尘纸独特的结构和优异的性能,其在电磁屏蔽、可穿戴电子设备、太阳能海水淡化以及工业擦拭用品等领域具有广泛... 详细信息

无尘纸由纤维素纤维和聚酯组成,孔隙发达,具有优异的机械性能、耐折性和透气性。以无尘纸为载体制备功能复合材料,可以利用无尘纸独特的结构和优异的性能,其在电磁屏蔽、可穿戴电子设备、太阳能海水淡化以及工业擦拭用品等领域具有广泛应用前景。本文综述了三种类型无尘纸的特点和制备方法,并对其潜在应用进行了比较分析;从超级电容器电极、太阳能蒸发器、电磁屏蔽、传感器以及吸收芯等五个方面介绍了无尘纸功能复合材料的研究进展。最后,简要地总结了无尘纸功能复合材料的发展方向,以期为无尘纸复合材料的应用提供参考,开辟无尘纸功能化应用新途径。

关键词：无尘纸复合材料超级电容器太阳能蒸发器研究进展

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地下水灌溉对华北平原农田土壤碳库转化影响

环境科学研究 2021年第5期34卷 1187-1195页

作者：敦宇许嘉文白雪山禤映雪曹英杰靳潇锐赵玉川武超中国地质科学院水文地质环境地质研究所河北石家庄050061 中国地质调查局河北省地下水污染机理与修复重点实验室河北石家庄050061 中山大学环境科学与工程学院广东广州510006 广东省环境污染控制与修复技术重点实验室广东广州510006 河北省地质环境监测院河北石家庄050022

为揭示区域尺度上地下水灌溉对农田土壤碳库转化的作用机制,选取华北平原高灌溉定额区、低灌溉定额区及无灌溉背景区为研究对象,分析土壤深度0~700 cm剖面范围内碳含量及碳储量的变化特征,并结合稳定碳同位素源解析技术,采用端元混合模... 详细信息

为揭示区域尺度上地下水灌溉对农田土壤碳库转化的作用机制,选取华北平原高灌溉定额区、低灌溉定额区及无灌溉背景区为研究对象,分析土壤深度0~700 cm剖面范围内碳含量及碳储量的变化特征,并结合稳定碳同位素源解析技术,采用端元混合模型定量评估地下水灌溉条件下不同来源的土壤碳对土壤碳库的贡献率.结果表明:①地下水灌溉对土壤有机碳(SOC)储量影响不显著,但是显著增加了土壤无机碳(SIC)储量,具体趋势表现为无灌溉背景区(43.8 kg/hm^(2))<低灌溉定额区(46.9 kg/hm^(2))<高灌溉定额区(79.9 kg/hm^(2));垂向剖面数据进一步显示,灌溉区与无灌溉区碳密度在土壤深度100~300 cm处存在显著差异(p<0.01).②碳含量及稳定碳同位素相关分析表明,无灌溉条件下SOC和SIC间转化关系较为明显;而在地下水灌溉区SOC与SIC相关性较弱.地下水溶解性无机碳(DIC)输入成为灌溉区土壤无机碳库的主控因素.③稳定碳同位素源解析表明,SOC以C3植物来源为主,无灌溉区DIC主要来源于SOC转化,其占比在10.6%~25.8%之间;灌溉区DIC则主要来源地下水灌溉,占比范围为74.0%~89.8%.研究显示,地下水灌溉外源输入的DIC显著提高了SIC的储量,对区域土壤碳库组成及转化过程产生重要的直接影响.

关键词：地下水灌溉土壤碳库含量储量碳同位素

基于随机模拟的地下水铬污染健康风险动态评价

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南水北调与水利科技 2019年第6期17卷 121-126,137页

作者：敦宇武超杨帆靳潇锐吴国庆张兆吉费宇红中国地质科学院水文地质环境地质研究所石家庄050061 河北省地质环境监测院石家庄050021

在考虑污染场地水文地质参数的空间变异性以及浓度随时间变化的基础上,构建了污染场地健康风险动态评价模型。通过灵敏度分析选取空间变异对数值模拟影响较大的随机参数,运用地下水模拟系统(Groundwater Modeling System,GMS)中的蒙特... 详细信息

在考虑污染场地水文地质参数的空间变异性以及浓度随时间变化的基础上,构建了污染场地健康风险动态评价模型。通过灵敏度分析选取空间变异对数值模拟影响较大的随机参数,运用地下水模拟系统(Groundwater Modeling System,GMS)中的蒙特卡罗随机模拟得到敏感点污染物任意时刻的概率浓度分布特征,进而选取50%和95%分位点分别代表正常情况和最不利情况,预测敏感点健康风险历时变化特征。以石家庄市藁城区某铬化工污染场地为案例进行分析,结果表明,敏感点初始时健康风险值为0.81,在可以接受的风险范围内,污染羽运移1a后,在正常情况和最不利情况下,风险值分别为1.28、1.52,均大于1,即存在非致癌风险,随后逐渐增大,正常情况下,直到第13年才达到风险可接受水平,说明敏感点未来一段时间都存在较大的健康风险,因此需要对污染场地地下水进行修复。

关键词：随机理论灵敏度分析地下水铬污染健康风险

兰州窦家山典型坡面土壤水分、有机质含量及抗蚀性相关关系研究

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南京大学学报（自然科学版） 2018年第1期54卷 185-195页

作者：高鑫宇曾献奎吴吉春苏辉东杜东东张兆丰金晓蕊南京大学地球科学与工程学院南京210023 兰州大学资源环境学院兰州730000 清华大学水利水电工程系北京100084

通过取样实验和数据分析,研究了窦家山典型坡面五种不同植被类型下的土壤含水量和土壤有机质含量变化规律以及其与土壤抗蚀性之间的关系,为窦家山及兰州地区的水土流失防治提供参考措施.研究发现,在相同的土壤剖面深度和坡位条件下,不... 详细信息

通过取样实验和数据分析,研究了窦家山典型坡面五种不同植被类型下的土壤含水量和土壤有机质含量变化规律以及其与土壤抗蚀性之间的关系,为窦家山及兰州地区的水土流失防治提供参考措施.研究发现,在相同的土壤剖面深度和坡位条件下,不同植被类型土壤含水量大小顺序为银白杨>侧柏>柽柳>白沙蒿>醉马草,土壤有机质含量与含水量呈现负相关;相同条件下,不同植被类型有机质含量大小顺序为醉马草>白沙蒿>柽柳>侧柏>银白杨,不同植被类型有机质含量与大于0.25mm的水稳性团聚体含量均呈正相关关系;水稳性土壤团聚体含量大小顺序与有机质含量大小顺序相一致.大于0.25mm粒级水稳性团聚体含量越高,土壤抗蚀性越强,即水土流失量越少.从而有机质含量越高,土壤抗蚀性越好.结果表明,醉马草或白沙蒿的种植有利于窦家山的水土保持工作.

关键词：植被类型土壤含水量有机质含量水稳性团聚体土壤抗蚀性

A Two-Stage Vehicle Type Recognition Method Combining the Most Effective Gabor Features

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Computers, Materials & Continua 2020年第12期65卷 2489-2510页

作者： Wei Sun xiaorui Zhang Xiaozheng He Yan jin Xu Zhang School of Automation Nanjing University of Information Science&TechnologyNanjing210044China Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology Nanjing University of Information Science&TechnologyNanjing210044China Jiangsu Engineering Center of Network Monitoring Nanjing University of Information Science&TechnologyNanjing210044China Rensselaer Polytechnic Institute TroyNY 12180USA

Vehicle type recognition(VTR)is an important research topic due to its significance in intelligent transportation ***,recognizing vehicle type on the real-world images is challenging due to the illumination change,partial occlusion under real traffic *** difficulties limit the performance of current state-of-art methods,which are typically based on single-stage classification without considering feature *** address such difficulties,this paper proposes a two-stage vehicle type recognition method combining the most effective Gabor *** first stage leverages edge features to classify vehicles by size into big or small via a similarity k-nearest neighbor classifier(SKNNC).Further the more specific vehicle type such as bus,truck,sedan or van is recognized by the second stage classification,which leverages the most effective Gabor features extracted by a set of Gabor wavelet kernels on the partitioned key patches via a kernel sparse representation-based classifier(KSRC).A verification and correction step based on minimum residual analysis is proposed to enhance the reliability of the *** improve VTR efficiency,the most effective Gabor features are selected through gray relational analysis that leverages the correlation between Gabor feature image and the original *** results demonstrate that the proposed method not only improves the accuracy of VTR but also enhances the recognition robustness to illumination change and partial occlusion.

关键词： Vehicle type recognition improved Canny algorithm Gabor filter k-nearest neighbor classification grey relational analysis kernel sparse representation two-stage classification