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化学交联聚乙烯醇改性纤维素碱性阴离子交换复合膜的制备与性能

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物理化学学报 2011年第11期27卷 2665-2670页

作者：刘玲玲丁蕾徐莉乔锦丽盛嘉伟东华大学环境科学与工程学院上海201620 浙江工业大学化学工程与材料学院杭州310032

高稳定性碱性阴离子交换膜的制备已成为碱性固体电解质膜研究领域的一大热点.本文通过聚乙烯醇化学交联改性制备出了季铵化羟乙基乙氧基纤维素碱性阴离子交换膜(PVA/QHECE).采用傅里叶变换红外(FTIR)光谱、热重(TG)分析、交流(AC)阻抗... 详细信息

高稳定性碱性阴离子交换膜的制备已成为碱性固体电解质膜研究领域的一大热点.本文通过聚乙烯醇化学交联改性制备出了季铵化羟乙基乙氧基纤维素碱性阴离子交换膜(PVA/QHECE).采用傅里叶变换红外(FTIR)光谱、热重(TG)分析、交流(AC)阻抗等方法考察了复合膜的分子结构、热稳定性、耐碱稳定性及离子电导率等性能.详尽考察了交联时间、交联剂含量、聚合物组成对成膜力学强度、含水率以及OH^-电导率的影响.实验结果表明:随着交联时间的增加,膜的溶胀率降低,力学强度随之增强,而离子电导率随膜含水率的降低没有发生明显变化,室温下OH^-的电导率在3.26×10^(-4)-4.44×10^(-4)S·cm^(-1)范围内变化.热重分析结果显示:掺入42.9%的QHECE时,膜的热分解温度达260℃.此外,将PVA/QHECE膜在6 mol·L^(-4) KOH浓碱溶液中80℃浸渍处理168 h,膜的电导率从4.90×10^(-4)S·cm^(-1)提高到9.68×10^(-4)S·cm^(-1),而膜的外观和力学强度以及含水率未发生明显变化,这一结果表明该膜具有很好的耐碱化学稳定性,有望作为一种新型的碱性燃料电池用离子交换膜.

关键词：碱性阴离子交换膜聚乙烯醇季铵化羟乙基乙氧基纤维素共混化学交联 OH-电导率耐碱稳定性

Four-Dimensional Computerized Tomography (4D-CT) Reconstruction Based on the Similarity Measure of Spatial Adjacent Images

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Chinese Journal of Biomedical Engineering(English Edition) 2008年第3期17卷 106-113页

作者： ZHANG Shu-xu ZHOU ling-hong CHEN Guang-jie LIN sheng-qu YE Yu-sheng ZHANG Hai-nan Department of Radiotherapy Center the Affiliated Tumor Hospital of Guangzhou Medical College Guangzhou 510095 China School of Biomedical Engineering Southern Medical University Guangzhou 510515 China

Objective:To investigate the feasibility of a 4D-CT reconstruction method based on the similarity principle of spatial adjacent images and mutual information measure. Methods:A motor driven sinusoidal motion platform made in house was used to create one-dimensional periodical motion that was along the longitudinal axis of the CT couch. The amplitude of sinusoidal motion was set to an amplitude of ±1 cm. The period of the motion was adjustable and set to 3.5 s. Phantom objects of two eggs were placed in a Styrofoam block, which in turn were placed on the motion platform. These objects were used to simulate volumes of interest undergoing ideal periodic motion. CT data of static phantom were acquired using a multi-slice general electric (GE) LightSpeed 16-slice CT scanner in an axial mode. And the CT data of periodical motion phantom were acquired in an axial and cine-mode scan. A software program was developed by using VC++ and VTK software tools to resort the CT data and reconstruct the 4D-CT. Then all of the CT data with same phase were sorted by the program into the same series based on the similarity principle of spatial adjacent images and mutual information measure among them, and 3D reconstruction of different phase CT data were completed by using the software. Results:All of the CT data were sorted accurately into different series based on the similarity principle of spatial adjacent images and mutual information measures among them. Compared with the unsorted CT data, the motion artifacts in the 3D reconstruction of sorted CT data were reduced significantly, and all of the sorted CT series result in a 4D-CT that reflected the characteristic of the periodical motion phantom. Conclusion:Time-resolved 4D-CT reconstruction can be implemented with any general multi-slice CT scanners based on the similarity principle of spatial adjacent images and mutual information *** process of the 4D-CT data acquisition and reconstruction were not restricted to the hard

关键词：四维CT检查放射治疗肿瘤病理机制

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污泥-稻壳颗粒生物炭对水中阿莫西林的吸附

水处理技术 2023年第10期49卷 64-69页

作者：陈永亮李慧敏石磊王玲武汉科技大学资源与环境工程学院国家环境保护矿冶资源利用与污染控制重点实验室湖北武汉430081

以给水污泥与稻壳为主要原料,添加适量的聚乙烯醇、磷酸和海泡石,通过真空热解方式制备一种悬浮颗粒吸附材料,并将其用于模拟废水中阿莫西林的去除。通过批量吸附试验考察了吸附剂投加量、溶液pH、污染物初始浓度及吸附时间等参数对吸... 详细信息

以给水污泥与稻壳为主要原料,添加适量的聚乙烯醇、磷酸和海泡石,通过真空热解方式制备一种悬浮颗粒吸附材料,并将其用于模拟废水中阿莫西林的去除。通过批量吸附试验考察了吸附剂投加量、溶液pH、污染物初始浓度及吸附时间等参数对吸附效果的影响,通过等温吸附模型和动力学模型研究其吸附行为,并利用BET、XRD、SEM-EDS及FTIR探究吸附机理。结果表明,在阿莫西林初始浓度为40 mg/L、颗粒吸附材料投加量为6 g/L、pH为8、吸附时间为90 min、温度为25℃的条件下,溶液中阿莫西林最大去除率为77.98%。等温吸附曲线和吸附动力学结果表明,该吸附过程与Langmiur等温吸附模型、准二级动力学模型的拟合较好,表明吸附材料对阿莫西林的吸附过程主要为单分子层的化学吸附。微观分析表明,吸附材料主要是通过吸附材料表面的羧基或醛基吸附废水中阿莫西林。

关键词：给水污泥稻壳阿莫西林吸附

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一类非光滑方程的类梯度算法

长沙水电师院学报（自然科学版） 2000年第1期15卷 15-17页

作者：凌生智湖南女子职业大学湖南长沙410004

提出了与双障碍问题等价的非光滑方程的类梯度算法 ,并在一定条件下证明了该算法的收敛性定理 .数值试验表明该算法是有效的 .

关键词：非光滑方程类梯度法收敛性

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论民主政治的推进对中国共产党公信力的提升

湖南师范大学社会科学学报 2014年第1期43卷 53-60页

作者：凌应生湖南师范大学湖南长沙410081

民主政治、政党公信力在政党政治中以公共权力为中心呈现为映像关系,民主政治的实现程度直接影响政党公信力的提升。中国共产党在革命和建设时期,不断加强民主政治建设以提升党的公信力。在新的历史条件下,要进一步提升党的公信力,必须... 详细信息

民主政治、政党公信力在政党政治中以公共权力为中心呈现为映像关系,民主政治的实现程度直接影响政党公信力的提升。中国共产党在革命和建设时期,不断加强民主政治建设以提升党的公信力。在新的历史条件下,要进一步提升党的公信力,必须坚定执政的人民立场、充分实现民众合理的利益诉求、强化公权力运用的规范性和完善党的执政方式。

关键词：中国共产党民主政治公信力提升

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大跨度连续钢箱梁横隔板的合理布置

中国铁道科学 2012年第B08期33卷 86-91页

作者：方兴白玲史永吉中国铁道科学研究院铁道科学技术研究发展中心北京100081

根据偏心荷载作用下钢箱梁的受力特点，从分析畸变翘曲应力的角度出发研究钢箱梁横隔板的合理布置。提出采用弹性支承连续梁比拟法分析大跨度变截面钢箱梁的畸变翘曲应力。根据单室矩形箱梁畸变控制微分方程与弹性地基梁弯曲控制微分方... 详细信息

根据偏心荷载作用下钢箱梁的受力特点，从分析畸变翘曲应力的角度出发研究钢箱梁横隔板的合理布置。提出采用弹性支承连续梁比拟法分析大跨度变截面钢箱梁的畸变翘曲应力。根据单室矩形箱梁畸变控制微分方程与弹性地基梁弯曲控制微分方程的相似性，将单室矩形箱梁的畸变比拟成弹性支承连续梁的弯曲，据此求解考虑横隔板间距和刚度影响的单室矩形箱梁的畸变翘曲应力。以控制箱梁畸变翘曲应力不超过弯曲正应力15％为目标采用该方法确定崇启大桥横隔板的合理布置形式为：当横隔板间距设置为5.6m时，在各墩墩顶宜采用实腹式横隔板；在其他位置可采用桁架式横隔板。

关键词：连续钢箱梁横隔板畸变翘曲应力弹性支承连续梁比拟法

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一种感兴趣目标区域自动插值算法

西安电子科技大学学报 2006年第2期33卷 195-199,246页

作者：史凌峰郭宝龙西安电子科技大学机电工程学院陕西西安710071

针对探地雷达成像需要自动放大感兴趣目标区域,同时抑制其他背景区域问题,提出了一种感兴趣目标区域自动插值方法.该方法通过二次统计检测地下目标的水平位置,且自动分割测线,之后用菱形模板预处理目标测线,用统计方法自动检测出目标深... 详细信息

针对探地雷达成像需要自动放大感兴趣目标区域,同时抑制其他背景区域问题,提出了一种感兴趣目标区域自动插值方法.该方法通过二次统计检测地下目标的水平位置,且自动分割测线,之后用菱形模板预处理目标测线,用统计方法自动检测出目标深度位置,并对目标区域进行相关增强,最后对感兴趣的目标区域用实时插值方法放大,同时抑制背景.在不同的应用场合可选取相应模型,不仅实现感兴趣目标的自动检测,而且对目标区域实现自动增强,有利于目标定位和识别.实测数据表明该方法具有很好的适应性和可靠性.

关键词：插值算法感兴趣目标探地雷达

Minimum Amounts of Extracting Solvent of (A1A2···At-1)/(A2A3···At) Countercurrent Extraction Separation

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Advances in Materials Physics and Chemistry 2015年第8期5卷 325-336页

作者： Fu-Xiang Cheng sheng Wu Song-ling Wang Bo Zhang Yan Liu Chun-sheng Liao Chun-Hua Yan China Minmetals (Beijing) Research Institute of RE Co. Ltd. Beijing China Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications PKU-HKU Joint Lab on Rare Earth Materials and Bioinorganic Chemistry Peking University Beijing China

Minimum amounts of extracting solvent and scrubbing agent solution (denoted as Smin and Wmin respectively) mean the theoretical minimal requirements for chemicals to achieve a specified separation duty, and therefore attract more concerns in the process design of countercurrent extraction separation. Over the past decade, hyperlink extraction technology has been widely used in rare earth separation industry in China with the target to decrease chemical consumption as well as pollution discharges. However, the equations of Smin and Wmin derived in the earlier version of the theory of countercurrent extraction can only be correctly applied to two-component separation and become invalid for hyperlink processes. It is significant to develop new aspects of the theory for design of the hyperlink processes. The separation of (A1A2···At-1)/(A2A3···At) is the basic configuration in the hyperlink processes differently from in conventional processes, where A1, A2, ···, At represent different kinds of rare earth ions with the same number of valence. The separations of two and three components have been discussed and the equations of Smin and Wmin are derived in our previous works. Nevertheless, it is still significant, especially for rare earth separations, to investigate the separations with more components. The present article will therefore focus on developing new expressions for Smin and Wmin applied to the (A1A2···At﹣1)/(A2A3···At) separation. Also a five-component separation case is simulated according to the derived equations. This work is an essential part of the new theory to design the hyperlink extraction processes.

关键词： Theory of Countercurrent Extraction Minimum Amount of Extracting Solvent Countercurrent Extraction Hyperlink Process Multi-Component Separation

Infection of sheep by Echinococcus multilocularis in Gansu,China:evidence from mitochondrial and nuclear DNA analysis

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Infectious Diseases of Poverty 2023年第4期12卷 107-107页

作者： Nigus Abebe Shumuye Li Li Wen-Hui Li Nian-Zhang Zhang Yan-Tao Wu Yao-Dong Wu Wen-Jun Tian Lin-sheng Zhang Xiao-Feng Nian Guo-Dong Dai Wei-Gang Chen sheng-Zhi Gao Xue-Qi Tian Jun-shi Liu Bin Li Nigatu Kebede Bao-Quan Fu Hong-Bin Yan Wan-Zhong Jia State Key Laboratory for Animal Disease Control and Prevention College of Veterinary Medicine National Para-Reference Laboratory for Animal Echinococcosis Key Laboratory of Veterinary Parasitology of Gansu Province Lanzhou Veterinary Research Institute Lanzhou University Chinese Academy of Agricultural Sciences Lanzhou China Department of Veterinary Clinical Medicine and Epidemiology Mekelle University College of Veterinary Sciences Kalamino Campus Mekelle Ethiopia Gansu Animal Centre for Disease Control and Prevention Lanzhou China Jingyuan County Animal Centre for Disease Control and Prevention Jingyuan County Animal Husbandry and Veterinary Technical Service Center Jingyuan China Aklilu Lemma Institute of Pathobiology Addis Ababa University Addis Ababa Ethiopia Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses Yangzhou China

BackgroundIn the normal life cycle of the parasite(Echinococcus multilocularis)that causes alveolar echinococcosis,domestic and wild carnivores act as definitive hosts,and rodents act as intermediate *** presented study contributes to the research on the distribution and transmission pattern of *** in China having identified sheep as an unusual intermediate host taking part in the domestic transmission of alveolar echinococcosis in Gansu Province,*** 2020 to 2021,nine whitish different cyst-like were collected from the liver of sheep in Gansu Province for examination.A near complete mitochondrial(mt)genome and selected nuclear genes were amplified from the cyst-like lesion for *** confirm the status of the specimen,comparative analysis with reference sequences,phylogenetic analysis,and network analysis were *** isolates displayed≥98.87%similarity to *** NADH dehydrogenase sub-unit 1(nad1)(894 bp)reference sequences deposited in ***,amplification of the nad4 and nad2 genes also confirmed all nine samples as *** with>99.30%***,three nuclear genes,pepck(1545 bp),elp-exons VII and VIII(566 bp),and elp-exon IX(256 bp),were successfully amplified and sequenced for one of the isolates with 98.42%similarity,confirming the isolates were correctly identified as *** analysis also correctly placed the isolates with other *** a result of the discovery of *** in an unusual intermediate host,which is considered to have the highest zoonotic potential,the result clearly demonstrated the necessity for expanded surveillance in the area.

关键词： Echinococcus multilocularis China Sheep Liver Phylogeny