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Dual-selective detection of CO and CH_(4) based on hierarchical porous In_(2)O_(3) nanoflowers with Pd modification

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Journal of Materiomics 2022年第3期8卷 545-555页

作者： Liuyang Han saisai zhang Bo zhang Bowen zhang Yan Wang Hari Bala Zhanying zhang School of Materials Science and Engineering Cultivating Base for Key Laboratory of Environment-friendly Inorganic Materials in University of Henan ProvinceHenan Polytechnic UniversityJiaozuo454000China State Key Laboratory Cultivation Bases for Gas Geology and Gas Control(Henan Polytechnic University) Jiaozuo454000China

The timely and effective detection of CO and CH_(4) is critical as the explosion and poisoning of them can bring serious potential risks to coal mining.In this study,combining metal oxide semiconductors with noble metals offers a promising route to achieve this target.Hierarchical porous Pd modified In_(2)O_(3) nanoflowers were prepared via two-step hydrothermal method and exhibited dual detection of CO and CH_(4) at different temperatures.The material has been characterized by a number of advanced techniques and the results indicate that Pd modified In_(2)O_(3) are hierarchical porous nanoflowers structure consisting of pores of approximately 1.8 nm in size.The sensing properties results show that the Pd modified In_(2)O_(3) based sensor exhibits temperature-dependent dual selectivity detection of CO at 280℃ and CH_(4) at 340℃.In addition,the Pd modified In_(2)O_(3) sensor display higher sensing response of CO(5.824 for 100 ppm)and CH_(4)(1.162 for 1000 ppm),fast response and recovery time,as well as good repeatability,which demonstrating the great potential for practical application.Such good gas-sensing performance are mainly attributed to the unique flower-like structure,the presence of porosity on the sample surface,and the catalytic effect of Pd.

关键词： Hierarchical porous structure Pd/In_(2)O_(3)nanoflowers Gas sensor Dual selectivity CO and CH_(4)

Evaluation methods and indexes of morphological characteristics of coarse aggregates for road materials:A comprehensive review

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第3期6卷 256-272页

作者： saisai zhang Rui Li Jianzhong Pei School of Highway Chang’an University

The morphological characteristics of coarse aggregates, namely shape profile, angularity and surface texture, have a significant effect on the mechanical properties of asphalt mixtures. The identification methods and evaluation indexes of the morphological characteristics are crucial for the coarse aggregates. First, the visual identification technologies, including charged coupled device (CCD) image processing, X-ray tomography imaging and laser scanning technology, are summarized in term of the characteristics, research status and existing problems. Based on the deficiencies of visual identification technologies, it is proposed to improve the three-dimensional reconstruction of aggregate particles by increasing the number of two-dimensional projection directions or scanning sections. Moreover, the evaluation indexes of coarse aggregate morphology were summarized from the three aspects, namely shape profile, angularity and surface texture. It is found that evaluation of the indexes based on two-dimensional profile images or unrelated to pavement performance could not adequately evaluate the morphological characteristics of coarse aggregates. Therefore, the evaluation methods and indexes of coarse aggregate morphological characteristics have been recommended based on the performance of asphalt mixtures in this paper, which is helpful to establish a complete set of an evaluation system for coarse aggregate morphology.

关键词： Road material Coarse aggregate Morphological characteristic Identification method Evaluation index

Copper-Mediated Cyanation of Aryl C H Bond with Removable Bidenate Auxiliary Using Acetonitrile as the Cyano Source

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Chinese Journal of Chemistry 2018年第12期36卷 1139-1142页

作者： Zhengwei Yu saisai zhang Zengming Shen Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs School of Chemistry and Chemical EngineeringShanghai Jiao Tong University800 Dongchuan RoadShanghai 200240China

Copper‐mediated cyanation of aryl C—H bond with removable bidenate auxiliary as a directing group has been developed, in which green and cheap acetonitrile is used as the “CN” source. By switching the reaction conditions, the C—H cyanated products and N ‐Ar‐phthalimides can be provided in acceptable yields with high chemoselectivity, respectively. The use of quaternary ammonium salt is essential for cyanation reaction.

关键词： cyanation copper catalyst aryl C—H bond activation acetonitrile N‐Ar‐phthalimides

Characterization of the bacterial communities associated with biofilters in two full-scale recirculating aquaculture systems

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Journal of Oceanology and Limnology 2021年第3期39卷 1143-1150页

作者： Yuexin MA Xin DU Yubin LIU Tao zhang Yue WANG saisai zhang Key Laboratory of Environment Controlled Aquaculture Ministry of EducationDalian 116023China Dalian Modern Agricultural Production Development Service Center Dalian 116023China Dalian Tianzheng Industry Company Limited Dalian 116011China

Bacteria play a major role in metabolizing ammonia and other metabolites in recirculating aquaculture systems(RASs).To characterize and compare the bacterial communities in the biofilters of two full-scale RASs for the culture of puffer fish,Takifugu rubripes,at different ages and densities were studied.In overall,47807 optimized reads of the 16 S rRNA gene with V4-V5 region were obtained from four biofilm samples collected after biofilm maturation.At 97%cut-off level,these sequences were clustered into 500 operational taxonomic units,and were classified into 19 bacterial phyla and 138 genera.At the phylum level,Proteobacteria and Bacteroidetes were the most abundant,followed by Nitrospirae and Planctomycetes.At the genus level,Colwellia,Marinifilum,Oceanospirillum,Lutibacter,Winogradskyella,Pseudoalteromonas,Arcobacter,and Phaeobacter were the top members.Nitrosomonas and Nitrospira were main ammonia-and nitrite-oxidizing bacteria.Differences in bacterial communities at different sampling dates and similarities of both biofilters were revealed in the Venn diagram and cluster analysis.Maintaining a good water quality and health offarmed fish in RASs depended on the correct management of the bacterial communities.This study provides more accurate information on the bacterial communities associated with the bifilters of both RASs.

关键词： biofilters bacterial community recirculating aquaculture system Illumina-MiSeq sequencing

The rapid detection for methane of ZnO porous nanoflakes with the decoration of Ag nanoparticles

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Frontiers of Materials Science 2021年第4期15卷 621-631页

作者： Liuyang HAN saisai zhang Bo zhang Bowen zhang Yan WANG Hari BALA Zhanying zhang School of Materials Science and Engineering Cultivating Base for Key Laboratory of Environment-friendly Inorganic Materials in University of Henan ProvinceHenan Polytechnic UniversityJiaozuo 454000China State Key Laboratory Cultivation Bases for Gas Geology and Gas Control(Henan Polytechnic University) Jiaozuo 454000China

Realizing the real-time detection of CH4 is important for the safety of human life.A facile hydrothermal method was used to synthesize Ag nanoparticlesdecorated ZnO porous nanoflakes(PNFs)in this study.The characterization results confirmed that Ag nanoparticles had been decorated in ZnO nanoflakes with the thickness of~10 nm.The gas-sensing properties of Ag-decorated ZnO nanoflakes were also investigated.While the gas-sensing performances of ZnO were remarkably improved by decorating Ag nanoparticles on the surface of ZnO nanoflakes,the response of the Agdecorated ZnO sensor to 3000 ppm CH4 is almost 1.3 times as high as that of pristine ZnO sensor.The obtained Ag/ZnO sensor exhibits better long-term stability and shorter response recovery time(5/38 s)in the comparison with pristine ZnO,demonstrating the possibility for the actual detection of CH4.The enhanced CH4 sensing performance can be attributed to the synergism between the unique hierarchical porous structure and the sensitizing actions utilized by the Ag nanoparticles.

关键词： hierarchical structure ZnO porous nanoflake Ag nanoparticle methane sensitivity

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卒中后疲劳患者筛查与管理的最佳证据总结

中国实用护理杂志 2024年第3期40卷 211-217页

作者：张赛赛董新寨张娜丽张俊萍赵芳山西医科大学护理学院太原030001 山西医科大学第二医院护理部太原030001

目的检索、评价并总结卒中后疲劳患者筛查管理的最佳证据,为临床医护人员早期识别管理提供依据。方法按照"6S"金字塔模型,系统检索UpToDate、BMJ最佳临床实践、国际指南协作网、新西兰指南协作组、加拿大安大略注册护士协会网站、苏格... 详细信息

目的检索、评价并总结卒中后疲劳患者筛查管理的最佳证据,为临床医护人员早期识别管理提供依据。方法按照"6S"金字塔模型,系统检索UpToDate、BMJ最佳临床实践、国际指南协作网、新西兰指南协作组、加拿大安大略注册护士协会网站、苏格兰院际间指南网、澳大利亚乔安娜布里格斯研究所循证卫生保健中心数据库、医脉通、美国卒中协会、加拿大心脏与卒中基金会、澳洲国家卒中基金会、英国卒中协会、国家卒中中心、Cochrane Library、PubMed、Embase、CINAHL、中国知网、万方数据库、维普期刊数据库、中国生物医学文献数据库中关于卒中后疲劳患者筛查与管理的相关证据。检索时限为2013年1月至2023年5月。研究者对文献进行筛选、质量评价及证据汇总。结果共纳入15篇文献,其中临床决策1篇、指南3篇、专家共识3篇、证据总结2篇、系统评价5篇、随机对照试验1篇。从筛查评估、危险因素、心理社会干预、活动与休息、健康教育、补充疗法、随访7个方面汇总了22条证据。结论该研究总结了卒中后疲劳患者筛查与管理的最佳证据,以更加科学系统的方法管理卒中后疲劳,为改善卒中患者长期生命质量提供参考。

关键词：疲劳循证医学卒中管理证据总结

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基于对比度和饱和度新的先验图像去雾算法

包装工程 2024年第11期45卷 191-197页

作者：张赛赛田益民王飞杜云飞北京印刷学院信息工程学院北京102600 北京印刷学院基础教育学院北京102600

目的针对目前图像印刷中清晰度和分辨率不高,为了提高图像的质量和观感,使雾图像细节更清晰,处理效率更高,文中设计一种基于对比度和饱和度的新的图像去雾先验算法。方法首先对采集的雾图像利用对比度、饱和度和亮度先验来初步估计透射... 详细信息

目的针对目前图像印刷中清晰度和分辨率不高,为了提高图像的质量和观感,使雾图像细节更清晰,处理效率更高,文中设计一种基于对比度和饱和度的新的图像去雾先验算法。方法首先对采集的雾图像利用对比度、饱和度和亮度先验来初步估计透射图,然后借助伽马校正的非线性逆策略增强图像的对比度和饱和度来防止传输估计过高或过低,并利用导向滤波对非线性逆策略的粗透射估计进行优化处理,最后使用非线性对比度拉伸方法对复原图像进行亮度进一步的增强。结果通过实验测试得出,对一个450×450的图像,本文提出的算法相较目前最新算法在PNSR值和SSIM值分别提高了9.2204和0.3327,处理时间减少了0.07938s。结论图像复原效果较好,细节更加丰富,清晰度更高,效率更高。

关键词：图像去雾导向滤波非线性逆策略对比度饱和度

乌鲁木齐市主城区生活性服务业空间格局及影响因素研究

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内蒙古师范大学学报（自然科学版） 2024年第2期53卷 163-172页

作者：张赛赛胡江玲王梦杰新疆师范大学地理科学与旅游学院新疆乌鲁木齐830054

以乌鲁木齐市主城区生活性服务业POI数据为基础,采用GIS空间分析、地理探测器等方法,分析乌鲁木齐市主城区生活性服务业空间分布格局及其影响因素。结果表明:(1)主城区生活性服务业呈现“内密外疏”的分布特征,空间分布不均衡;(2)各类... 详细信息

以乌鲁木齐市主城区生活性服务业POI数据为基础,采用GIS空间分析、地理探测器等方法,分析乌鲁木齐市主城区生活性服务业空间分布格局及其影响因素。结果表明:(1)主城区生活性服务业呈现“内密外疏”的分布特征,空间分布不均衡;(2)各类生活性服务业在不同空间尺度上集聚差异明显,集聚峰值时批发零售业、餐饮住宿区位选择空间范围最大,金融机构区位选择空间范围最小;(3)各类生活性服务业在空间分布上均有较强的关联性,餐饮住宿和各类生活性服务业联系较强,批发零售业与各类生活性服务业联系较弱;(4)在空间演化方向上,各类生活性服务业空间走向基本一致,呈西北-东南发展态势,且分布重心大致相同;(5)人口密度和交通条件是影响主城区生活性服务业的主导因素,因子的交互作用对生活性服务业分布的空间影响力更为显著。

关键词： POI数据生活性服务业空间分布影响因素乌鲁木齐

天山北坡城市群高质量测度与障碍因子诊断研究

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内蒙古师范大学学报（自然科学版） 2024年第3期53卷 246-253页

作者：王梦杰胡江玲张赛赛新疆师范大学地理科学与旅游学院新疆乌鲁木齐830054

通过熵权TOPSIS方法,测度2020年天山北坡城市群高质量发展水平,并采用障碍因子模型和耦合协调模型,判定影响高质量发展的障碍因子和城市内部协调度。结果表明:高质量综合得分排名为乌鲁木齐市>克拉玛依市>石河子市>吐鲁番市>五家渠市>... 详细信息

通过熵权TOPSIS方法,测度2020年天山北坡城市群高质量发展水平,并采用障碍因子模型和耦合协调模型,判定影响高质量发展的障碍因子和城市内部协调度。结果表明:高质量综合得分排名为乌鲁木齐市>克拉玛依市>石河子市>吐鲁番市>五家渠市>昌吉市>阜康市;影响乌鲁木齐市主要障碍因子是建成区绿化覆盖率、每万人图书馆数量、人均城市道路面积、建成区排水管道密度;其余城市的主要障碍因子是进出口贸易额、城市GDP、每万人专利授予量、参加基本养老保险的人数;乌鲁木齐市属于轻度失调,石河子市、克拉玛依市和昌吉市属于严重失调,吐鲁番市、五家渠市和阜康市属于极度失调。天山北坡城市群高质量发展水平与内部耦合协调水平低且呈非均衡的空间分布格局,未来应充分发挥各市的区位、资源和产业优势,着力补齐短板,注重全方位协调发展,提升发展质量。

关键词：天山北坡城市群高质量发展熵权-TOPSIS 障碍因子协调度