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Peroxymonosulfate enhanced photoelectrocatalytic oxidation of organic contaminants and simultaneously cathodic recycling of silver

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Journal of Environmental Sciences 2022年第10期34卷 74-83页

作者： Huixin shao xia Li Juanjuan Zhang Xu Zhao Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Beijing Capital Co.Ltd. Beijing 100028China

Degradation of organic contaminants with simultaneous recycling of Ag+from silvercontaining organic wastewater such as photographic effluents is desired. Although photoelectrocatalysis(PEC) technology is a good candidate for this type of wastewater, its reaction kinetics still needs to be improved. Herein, peroxymonosulfate(PMS) was employed to enhance the PEC kinetics for oxidation of phenol(PhOH) at the anode and reduction of Ag^(+) at the cathode. The degradation efficiency of phenol(PhOH, 0.1 mmol/L) was increased from 42.8% to 96.9% by adding 5 mmol/L PMS at a potential of 0.25 V. Meanwhile, the Ag(by wt%)deposited on the cathode was 28.1%(Ag_(2)O) in PEC process, while that of Ag(by wt%) was 69.7%(Ag^(0)) by adding PMS. According to the electrochemistry analysis, PMS, as photoelectrons acceptor, enhances the separation efficiency of charges and the direct hoxidation of Ph OH at the photoanode. Meantime, the increasing cathode potential avoided Hevolution and strongly alkaline at the surface of cathode, thus enabling the deposition of Ag+in the form of metallic silver with the help of PMS. In addition, PMS combined with PEC process was effective in treating photographic effluents.

关键词： Peroxymonosulfate Photoelectrocatalysis Organic contaminants degradation Silver recycling Photographic effluents

Electrocatalytic reduction of nitrate using Pd-Cu modified carbon nanotube membranes

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Frontiers of Environmental Science & Engineering 2023年第4期17卷 1-11页

作者： Zhijun Liu Xi Luo Senlin shao Xue xia College of Life and Environmental Sciences Minzu University of ChinaBeijing 100081China School of Civil Engineering Wuhan UniversityWuhan 430072China Yangtze Ecology and Environment Co. Ltd.Wuhan 430062China

Excessive nitrate in water is harmful to the ecological environment and human *** reduction is a promising technology for nitrate ***,a Pd-Cu modified carbon nanotube membrane was fabricated with an electrodeposition method and used to reduce nitrate in a flowthrough electrochemical *** optimal potential and duration for codeposition of Pd and Cu were-0.7 V and 5 min,respectively,according to linear scan voltammetry *** membrane obtained with a Pd:Cu ratio of 1:1 exhibited a relatively high nitrate removal efficiency and N_(2)*** was almost completely reduced(~99%)by the membrane at potentials lower than-1.2 ***,-0.8 V was the optimal potential for nitrate reduction in terms of both nitrate removal efficiency and product *** nitrate removal efficiency was 56.2%,and the N_(2)selectivity was 23.8%for the Pd:Cu=1:1 membrane operated at-0.8 *** removal was enhanced under acidic conditions,while N_(2)selectivity was *** concentrations of Cl-ions and dissolved oxygen showed little effect on nitrate *** mass transfer rate constant was greatly improved by 6.6 times from 1.14×10^(-3)m/h at a membrane flux of 1 L/(m^(2)·h)to 8.71×10^(-3)m/h at a membrane flux of 15 L/(m^(2)·h),which resulted in a significant increase in the nitrate removal rate from 13.6 to 133.5 mg/(m^(2)·h).These findings show that the Pd-Cu modified CNT membrane is an efficient material for nitrate reduction.

关键词： Pd-Cu modified CNT membrane Nitrate reduction Flow-through Electrodeposition Electrocatalytic reduction

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基于双目视觉和改进YOLOv8n的火灾检测及测距方法

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陕西科技大学学报 2025年第1期43卷 152-160页

作者：刘振董绍江罗家元孙世政潘学娇重庆交通大学机电与车辆工程学院重庆400074

针对火灾检测出现的漏检误检、模型参数量大及定位困难的问题,基于双目视觉和改进YOLOv8n提出了一种轻量化火灾检测及测距方法.通过双目相机拍摄图片,使用改进的检测算法YOLOv8n-AEM和现有的测距算法SGBM进行检测和测距.首先,在主干网... 详细信息

针对火灾检测出现的漏检误检、模型参数量大及定位困难的问题,基于双目视觉和改进YOLOv8n提出了一种轻量化火灾检测及测距方法.通过双目相机拍摄图片,使用改进的检测算法YOLOv8n-AEM和现有的测距算法SGBM进行检测和测距.首先,在主干网络中引入可变核卷积AKConv和EMA注意力机制,通过构建不规则卷积核有效提取火灾的特征;然后,在颈部网络中构建C2f-SCConv模块,通过特征重组降低模型参数,提高检测速度;其次,基于最小点距离改进损失函数,解决火源与光源重叠导致的漏检与误检问题;最后,增加小目标检测头,提高对小火苗的检测能力.实验结果表明,改进后的检测算法P、R、mAP分别为83.6%、76.4%、83.6%,分别提高了2.5%、3.6%、4.8%;参数量和模型大小分别为2.54 M和5.1 MB,分别降低了15.3%和15%;测距精度误差不超过2.5%,证明改进的方法能准确完成火灾的检测及测距.

关键词：火灾检测双目视觉测距 YOLOv8n 轻量化

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污泥免烧砖的制备及闷料效应的试验研究

非金属矿 2025年第1期48卷 100-104页

作者：邵国建夏亭河海大学力学与工程科学学院江苏南京211100

本试验以建筑垃圾、水泥、含水率54%的污泥及减水剂作为主要原材料制备免烧砖。通过探究养护时间、污泥掺量、污泥与减水剂闷料时间对免烧砖性能的作用,探讨了影响污泥免烧砖强度的微观机理。结果表明,当污泥免烧砖的配合比设定为25%水... 详细信息

本试验以建筑垃圾、水泥、含水率54%的污泥及减水剂作为主要原材料制备免烧砖。通过探究养护时间、污泥掺量、污泥与减水剂闷料时间对免烧砖性能的作用,探讨了影响污泥免烧砖强度的微观机理。结果表明,当污泥免烧砖的配合比设定为25%水泥、40%污泥、35%建筑垃圾,且污泥与减水剂闷料1 h,在标准养护箱里养护28 d后抗压强度提升到13.4 MPa,吸水率降低为18%,软化系数提高为0.90,20次冻融循环后的强度损失率和质量损失率分别降低到1%和0.8%。X射线衍射(XRD)微观试验表明,水化产物钙矾石的衍射峰较高,其含量最大,衍射峰值最大可达7016.7 s^(-1),促进了污泥免烧砖的水泥水化反应。扫描电镜(SEM)微观试验结果显示,此时试样的致密度达到最佳状态,表观密度也最大。

关键词：污泥闷料免烧砖抗压强度抗冻融性能

Construction of Solutions and L^1-error Estimates of Viscous Methods for Scalar Conservation Laws with Boundary

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Acta Mathematica Sinica,English Series 2007年第3期23卷 393-410页

作者： Hong xia LIU Tao pan Department of Mathematics Jinan University Guangzhou 510632 P. R. China

This paper is concerned with an initial boundary value problem for strictly convex conservation laws whose weak entropy solution is in the piecewise smooth solution class consisting of finitely many discontinuities. By the structure of the weak entropy solution of the corresponding initial value problem and the boundary entropy condition developed by Bardos-Leroux Nedelec, we give a construction method to the weak entropy solution of the initial boundary value problem. Compared with the initial value problem, the weak entropy solution of the initial boundary value problem includes the following new interaction type： an expansion wave collides with the boundary and the boundary reflects a new shock wave which is tangent to the boundary. According to the structure and some global estimates of the weak entropy solution, we derive the global L^1-error estimate for viscous methods to this initial boundary value problem by using the matching travelling wave solutions method. If the inviscid solution includes the interaction that an expansion wave collides with the boundary and the boundary reflects a new shock wave which is tangent to the boundary, or the inviscid solution includes some shock wave which is tangent to the boundary, then the error of the viscosity solution to the inviscid solution is bounded by O（ε^1/2） in L^1-norm; otherwise, as in the initial value problem, the L^1-error bound is O（ε｜ In ε｜）.

关键词： scalar conservation laws initial boundary value problem global weak entropy solution,error estimate of viscous methods

Predicting Chromatographic Retention Time of C10-Chlorinated Paraffins in Gas Chromatography-Mass Spectrometry Using Quantitative Structure Retention Relationship

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Chemical Research in Chinese Universities 2015年第2期31卷 192-197页

作者： xia Zhenzhen CAI Wensheng shao Xueguang Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) State Key Laboratory of Medicinal Chemical Biology Research Center for Analytical Sciences College of Chemistry Nankai University Tianjin 300071 P. R. China

Chlorinated paraffins（CPs） are potential persistent organic pollutants（POPs）, which threat the safety of environment and organisms. However, the analysis of CPs is a difficult task due to their complex composition containing thousands of congeners. In the present work, quantitative structure retention relationship（QSRR） of CPs was studied. A total of 470 molecular descriptors were generated, for describing the structures of 28 CPs and 12 descriptors relevant to retention time of the CPs were selected by stepwise regression. Then, QSRR models between retention time on the one hand and the selected descriptors on the other hand were established by multiple linear regres- sion（MLR）, partial least squares（PLS） and least square support vector regression（LS-SVR）. The result shows that PLS model is better than MLR and LS-SVR, obtaining a squared correlation coefficient（r2） of 0.9996 and a root mean squared error（RMSE） of 0.015. The PLS model was then used to predict the retention time of 49 C10-CPs. Three of them were investigated by gas chromatography coupled with mass spectrometry（GC-MS）. A well-defined correlation was found between the measured retention time and the predicted value.

关键词： Chlorinated paraffin Multivariate calibration Retention time Quantitative structure retention relationship

An M-VCUT level set-based data-driven model of microstructures and optimization of two-scale structures

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Frontiers of Mechanical Engineering 2024年第4期19卷 73-86页

作者： Minjie shao Tielin SHI Qi xia State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

The optimization of two-scale structures can adapt to the different needs of materials in various regions by reasonably arranging different microstructures at the macro scale,thereby considerably improving structural ***,a multiple variable cutting(M-VCUT)level set-based data-driven model of microstructures is presented,and a method based on this model is proposed for the optimal design of two-scale *** geometry of the microstructure is described using the M-VCUT level set method,and the effective mechanical properties of microstructures are computed by the homogenization ***,a database of microstructures containing their geometric and mechanical parameters is *** two sets of parameters are adopted as input and output datasets,and a mapping relationship between the two datasets is established to build the data-driven model of *** the optimization of two-scale structures,the data-driven model is used for macroscale finite element and sensitivity *** efficiency of the analysis and optimization of two-scale structures is improved because the computational costs of invoking such a data-driven model are much smaller than those of homogenization.

关键词： two-scale structure structural optimization M-VCUT level set homogenization radial basis function data-driven

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砂土应力-应变包络线的唯一性初探

岩土工程学报 2025年第2期47卷 265-274页

作者：邵龙潭高睿夏平心郭晓霞孙衍朴大连理工大学工业装备结构分析国家重点实验室辽宁大连116024 大连理工大学工程力学系辽宁大连116024 常州大学土木工程系江苏常州213164

土体循环加卸载外包络线是否具有唯一性在认识土体固有属性上具有重要意义。基于土样全表面变形数字图像测量系统,选用硅微粉和福建标准砂为研究对象,开展了一系列三轴剪切试验和三轴循环加卸载试验,探索等应力幅值、阶梯应力幅值和随... 详细信息

土体循环加卸载外包络线是否具有唯一性在认识土体固有属性上具有重要意义。基于土样全表面变形数字图像测量系统,选用硅微粉和福建标准砂为研究对象,开展了一系列三轴剪切试验和三轴循环加卸载试验,探索等应力幅值、阶梯应力幅值和随机应力幅值循环加卸载下应力-应变外包络线与相应的单调加载应力-应变曲线的一致性。试验结果表明土样在相同密度和围压条件下,单调加载的应力-应变曲线与经历不同循环应力历程的加卸载应力-应变外包络线近似一致,提出了砂土应力-应变外包络线的唯一性;讨论了循环应力历史和应力水平对曲线回归速度的影响以及应力-应变包络线唯一性在建立轴向应变累积模型中的应用。

关键词：应力-应变外包络线循环荷载砂土轴向累积应变

四物汤含药血清对多囊卵巢综合征卵巢颗粒细胞自噬的影响

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中国药房 2025年第2期36卷 185-190页

作者：邵艳社许雪梅杨宝芹李会娟姬霞河南省中医院/河南中医药大学第二附属医院妇产科郑州450011 河南中医药大学第一附属医院生殖科郑州450003

目的探讨四物汤含药血清对多囊卵巢综合征(PCOS)卵巢颗粒细胞自噬的影响及潜在机制。方法取3月龄雌性SD大鼠,分别以生理盐水和不同剂量四物汤灌胃,制备空白血清和不同浓度[0.52、1.04、2.08 g/(kg·d)]四物汤含药血清。筛选四物汤含... 详细信息

目的探讨四物汤含药血清对多囊卵巢综合征(PCOS)卵巢颗粒细胞自噬的影响及潜在机制。方法取3月龄雌性SD大鼠,分别以生理盐水和不同剂量四物汤灌胃,制备空白血清和不同浓度[0.52、1.04、2.08 g/(kg·d)]四物汤含药血清。筛选四物汤含药血清干预浓度后,将人卵巢颗粒细胞KGN分为对照组(细胞不进行任何处理)、脱氢表雄酮(DHEA)组(以50μmol/L的DHEA处理细胞48 h)、空白血清组(以50μmol/L的DHEA处理细胞48 h后,再用10%空白血清处理72 h)、中浓度四物汤含药血清组(以50μmol/L的DHEA处理细胞48 h后,再用10%中浓度四物汤含药血清处理72 h),观察各组细胞中的自噬体数量以及通路相关蛋白[果糖-1,6-二磷酸酶1(FBP1)、哺乳动物雷帕霉素靶蛋白(m TOR)、磷酸化mTOR(p-mTOR)]、自噬相关蛋白[p62、微管相关蛋白1轻链3(LC3)]和FBP1 mRNA的表达水平。将(转染)细胞分为四物汤组(以50μmol/L的DHEA处理细胞48 h后,再用10%中浓度四物汤含药血清处理72 h)、四物汤+si-NC组(以50μmol/L的DHEA处理阴性对照小干扰RNA转染细胞48 h后,再用10%中浓度四物汤含药血清处理72 h)、四物汤+si-FBP1组(以50μmol/L的DHEA处理FBP1小干扰RNA转染细胞48 h后,再用10%中浓度四物汤含药血清处理72 h),考察敲低FBP1对四物汤上述作用的影响。结果与对照组比较,DHEA组细胞的自噬体数量明显增加,LC3-Ⅱ/LC3-Ⅰ、p-mTOR/mTOR、FBP1蛋白及mRNA的表达水平均显著升高,p62蛋白的表达水平显著降低(P<0.05)。与DHEA组和空白血清组比较,中浓度四物汤含药血清组细胞的自噬体数量明显减少,LC3-Ⅱ/LC3-Ⅰ显著降低,p-mTOR/mTOR和p62蛋白、FBP1蛋白及mRNA的表达水平均显著升高(P<0.05)。敲低FBP1后,与四物汤+si-NC组比较,四物汤+si-FBP1组细胞的存活率、p62蛋白的表达水平、FBP1蛋白及mRNA的表达水平、p-mTOR/mTOR均显著降低,LC3-Ⅱ/LC3-Ⅰ显著升高(P<0.05)。结论四物汤可通过上调KGN细胞中FBP1蛋白及mRNA的表达来促进mTOR蛋白的磷酸化,从而抑制其自噬。

关键词：四物汤含药血清多囊卵巢综合征卵巢颗粒细胞 FBP1/mTOR信号通路

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