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生肌玉红膏联合威伐光治疗3期压力性损伤的疗效观察
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作者 习振文 魏清琳 +1 位作者 车永贵 普彬 《中国医药指南》 2024年第24期110-112,116,共4页
目的观察生肌玉红膏联合威伐光治疗3期压力性损伤的疗效。方法选取2019年8月至2022年12月期间我院3期压力性损伤患者90例(共计患处105处),按随机数字表法分为生-威组(生肌玉红膏+威伐光照射)30例(35处),生-紫组(生肌玉红膏外敷+紫外线照... 目的观察生肌玉红膏联合威伐光治疗3期压力性损伤的疗效。方法选取2019年8月至2022年12月期间我院3期压力性损伤患者90例(共计患处105处),按随机数字表法分为生-威组(生肌玉红膏+威伐光照射)30例(35处),生-紫组(生肌玉红膏外敷+紫外线照射)30例(37处)和生肌玉红膏组(生肌玉红膏外敷)30例(33处)。对比观察3组患者压力性损伤伤口面积、24 h渗液量及伤口床组织类型评分。结果治疗前3组患者压力性损伤伤口面积、24 h渗液量及伤口床组织类型评分均无统计学意义(P>0.05),治疗后3组患者伤口面积评分、24 h渗液量评分、伤口床组织类型评分均低于治疗前,且生-威组低于其他两组,生-紫组低于生肌玉红膏组(P<0.05)。结论生肌玉红膏联合威伐光治疗对3期压力性损伤的改善幅度最大,可有效促进压力性损伤创面的愈合。 展开更多
关键词 3期压力性损伤 生肌玉红膏 威伐光 压力性损伤伤口面积 24h渗液量
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2019~2022年华北平原典型地区不同污染等级和污染持续时间下的O_(3)污染规律及来源 被引量:1
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作者 钱昱先 王刚 +2 位作者 孟庆晓 刘赛 王永强 《中国环境科学》 EI CAS CSCD 北大核心 2024年第7期3581-3591,共11页
选取地势复杂的日照市莒县为研究区域,基于2019~2022年莒县省控站点的O_(3)监测数据,按照不同O_(3)污染等级与不同O_(3)污染持续时间对莒县的O_(3)污染天进行分类,探究其污染规律,并采用后向轨迹模型(HYSPLIT)、潜在源分析(PSCF)和浓度... 选取地势复杂的日照市莒县为研究区域,基于2019~2022年莒县省控站点的O_(3)监测数据,按照不同O_(3)污染等级与不同O_(3)污染持续时间对莒县的O_(3)污染天进行分类,探究其污染规律,并采用后向轨迹模型(HYSPLIT)、潜在源分析(PSCF)和浓度权重轨迹分析法(CWT)识别不同O_(3)污染事件下的O_(3)来源.结果显示:2019~2021年莒县O_(3)轻度污染天数由72d下降到38d,2022年反弹,而中度污染天数变化不大;轻微污染天在轻度污染天中占比较高(21.4%~39.5%),表明轻度污染天的改善空间很大,强化轻微污染天管控措施,将有利于将轻度污染天转化为优良天,提高当地空气质量优良率.O_(3)污染过程持续时间越长(如≥3d),污染发生的频率越低,而O_(3)浓度随污染持续时间的增加而升高.HYSPLIT模拟结果显示不同O_(3)污染等级和不同O_(3)污染持续时间的气团轨迹均以莒县东南方向为主,且以中、短距离传输为主,其中中度污染期间来自东南地区的O_(3)-8h-90%浓度最高[(250.0±65.9)µg/m^(3)].PSCF和CWT结果显示,O_(3)潜在源区主要分布在莒县东南方向,长江三角洲地区是莒县O_(3)污染的主要的潜在源区.研究结果对于指导莒县及周边区域的大气污染联防联控具有重要意义. 展开更多
关键词 臭氧 污染等级 污染持续时间 后向轨迹 潜在源区
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Assessment and Risk Zonation of Landslides in Panxi Area Based on 3S Technology 被引量:3
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作者 ZHANG Baolei SONG Shujun +1 位作者 FENG Wenlan ZHOU Wancun 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期793-800,共8页
Based on field survey located by GPS, it is obtained landslides' location and distribution information by the method of remote sensing in this paper. The vector data of environmental factors that breed and induce lan... Based on field survey located by GPS, it is obtained landslides' location and distribution information by the method of remote sensing in this paper. The vector data of environmental factors that breed and induce landslides such as the elevation, the slope, the vegetation cover, the lithology, the rainfall and so on are gained using GIS(geographical information system) techniques of spatial analysis. All the data obtained are managed through building landslide management system. At the same time, the system is made the platform to appraise the relationship between the distribution of landslides and the environmental factors. The results indicate: landslides take place relatively easily in the slope range between 10° and 25°; most landslides are in the mixed area of bush and grass with a coverage degree of from 20° to 65°; the distribution of landslides has a positive relationship with the distribution of annual rainfall. The risk degree of Panxi Area is zoned and mapped by the model of liner stack using GIS technique, and the result indicates: the place of high risk degree is the belt of Panzhihua-Miyi-Dechang-Mugu and southeast of Huili county and Huidong county,and area is about 512 707 hm^2. 展开更多
关键词 LANDSLIDE 3S technology risk zonation Panxi area
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黄河金三角地区城市O_(3)污染的时空格局演变特征 被引量:1
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作者 靳宁 王亚俊 +3 位作者 李丹 何亮 王成 李艳林 《环境科学研究》 CAS CSCD 北大核心 2024年第3期502-513,共12页
黄河金三角地区空气质量的改善是践行黄河流域生态保护和高质量发展的体现,科学认识O_(3)浓度时空演变和污染特征对于该地区大气污染联防联控具有重要意义.本研究融合地面观测和卫星遥感反演O_(3)浓度数据,采用统计分析、趋势分析及热... 黄河金三角地区空气质量的改善是践行黄河流域生态保护和高质量发展的体现,科学认识O_(3)浓度时空演变和污染特征对于该地区大气污染联防联控具有重要意义.本研究融合地面观测和卫星遥感反演O_(3)浓度数据,采用统计分析、趋势分析及热点分析的方法揭示黄河金三角地区O_(3)浓度的年、季节和月尺度以及空间变化特征,探究O_(3)污染等级的变化特征.结果表明:①黄河金三角地区2015−2022年4个地级市大气中O_(3)浓度呈升高趋势,O_(3)年均浓度表现为运城市(105μg/m^(3))>临汾市(103μg/m^(3))>三门峡市(97μg/m^(3))>渭南市(95μg/m^(3)).②O_(3)季均浓度总体表现为夏季(146μg/m^(3))>春季(113μg/m^(3))>秋季(83μg/m^(3))>冬季(59μg/m^(3)).③1−12月O_(3)浓度呈现抛物线的变化特征(5−9月偏高).④空间分布上,O_(3)浓度最大值和平均值的高值区域主要分布在黄河金三角地区东北到西南方向,低值区域分布在西北和东南方向,O_(3)浓度最小值的空间分布特征与此相反.⑤黄河金三角地区1−12月O_(3)浓度在北部、中部和南部均呈现高值和低值交替出现的空间聚集特征.NPP/VIIRS-O_(3)聚集区主要分布在该地区北部的5个区县,GDP-O_(3)聚集区零散分布在该地区的7个区县.⑥2015−2022年黄河金三角地区4个地市O_(3)不同污染等级的天数表现为优良(199 d)>轻度污染(123 d)>中度污染(46 d)>重度污染(7 d)>严重污染(0 d),优良和轻度污染的天数较多且优良的天数占到50%以上,轻度污染和中度污染出现的天数表现为夏季(77 d)>春季(58 d)>秋季(27 d)>冬季(6 d),优良的季节性变化特征则正好相反.研究成果对于揭示黄河金三角地区O_(3)时空演变规律及污染特征,制定科学合理的防治措施具有现实意义. 展开更多
关键词 黄河金三角地区 O_(3)污染 时空变化特征 卫星遥感反演 经济影响
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Effect of Aluminum on Long-Term Potentiation and Its Relation to L-arg-No-pathway in Hippocampal CA3 Area of Rats 被引量:1
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作者 邹本德 张自东 +1 位作者 肖鸿美 李艾 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1998年第4期193-196,200,共5页
Experiments were performed on 64 Sprague-Dawley rats under ure-thane anesthesia. Extracellular recording method was used to investigate the effect of aluminum (Al)microinjected into CA3 on long-term potentiation (LTP)... Experiments were performed on 64 Sprague-Dawley rats under ure-thane anesthesia. Extracellular recording method was used to investigate the effect of aluminum (Al)microinjected into CA3 on long-term potentiation (LTP) in this area. The relationship between the inhibitory effect of Al and L-arginine-NO pathway was also studied. Microinjection of Al (0. 5 mol/L, 1 μl ) into CA3 could block the induction of LTP in CA3. Microinjection of Al (0. 5 mol/L, 1 μl) into CA3 after LTP was induced could also decrease the amplitude of population spike (PS). The inhibitory effect of Al on LTP in CA3 could be enhanced by preinjection of NG-nitro-L-arginine (0. 3 mol/L, 1 μl). Preinjection of L-arginine (0. 3 mol/L, 1 μl) into CA3 could antagonize the inhibitory effect of Al on LTP. These results suggest that Al could block the induction of LTP and decrease the amplitude of PS potentiated in CA3. The effect of Al might be antagonized by L-arginine-NO pathway. 展开更多
关键词 CA3 area of hippocampus long-term potentiation ALUMINUM NG-ni-tro-L-arginine L-ARGININE
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微流控技术辅助制备多孔石墨相氮化碳(g-C3N4)块体及其性能研究
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作者 马千驰 徐倩鑫 +2 位作者 周何 郝彬琦 常振旗 《现代化工》 CAS CSCD 北大核心 2024年第3期90-96,共7页
设计了适用于微流控系统的原位生成酸催化聚乙烯醇/戊二醛凝胶反应体系并用于g-C_(3)N_(4)多孔微球粒径与形貌的可控制备,以无机粘结剂和多孔微球为原料实现氚兼容的多孔g-C_(3)N_(4)块体的制备。考察了凝胶组成成分、煅烧模式对微球比... 设计了适用于微流控系统的原位生成酸催化聚乙烯醇/戊二醛凝胶反应体系并用于g-C_(3)N_(4)多孔微球粒径与形貌的可控制备,以无机粘结剂和多孔微球为原料实现氚兼容的多孔g-C_(3)N_(4)块体的制备。考察了凝胶组成成分、煅烧模式对微球比表面积与机械强度的影响,以及无机黏合剂质量分数、微球粒径对g-C_(3)N_(4)块体比表面积与机械强度的影响。结果表明,微球粒径对块体材料性能有显著影响,在相同成型黏合剂质量分数下,微球粒径增加79.5%块体材料的比表面积提高205%,而机械强度仅降低了42%。4.5 K低温气体吸附实验结果表明,所制备的g-C_(3)N_(4)多孔块体吸附层对氢气和氦气的选择性系数可达13.02。 展开更多
关键词 g-C_(3)N_(4)多孔微球 多孔g-C_(3)N_(4)块体 比表面积 微流控技术 低温泵
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导电(Cu,Mn)_(3)O_(4)接触层在SOEC阳极侧的应用
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作者 黄旭锐 余喻天 +7 位作者 雷金勇 郝敬轩 俞传鑫 潘军 杨怡萍 廖梓豪 关成志 王建强 《材料导报》 EI CAS CSCD 北大核心 2024年第8期68-71,共4页
固体氧化物电解池(SOEC)中铁素体不锈钢合金连接体和电解池阳极之间存在界面接触、连接体表面氧化以及氧电极“铬毒化”等问题,是导致电解堆性能衰减的重要影响因素之一。本工作利用反应烧结工艺在连接体与阳极之间制备了多孔的(Cu,Mn)_... 固体氧化物电解池(SOEC)中铁素体不锈钢合金连接体和电解池阳极之间存在界面接触、连接体表面氧化以及氧电极“铬毒化”等问题,是导致电解堆性能衰减的重要影响因素之一。本工作利用反应烧结工艺在连接体与阳极之间制备了多孔的(Cu,Mn)_(3)O_(4)导电接触层,形成了粘结强度高的连接体/接触层/电解池界面结构。所得试样在750℃下表现出优异的电性能,整个500 h测试过程半电池的面比电阻(ASR)值稳定保持在20.13~20.32 mΩ·cm^(2)。通过微观结构表征技术证实,多孔(Cu,Mn)_(3)O_(4)接触层与相邻的电解堆部件具有良好的兼容性,并可以抑制连接体表面的氧化薄膜增长,同时阻止铬元素的迁移。(Cu,Mn)_(3)O_(4)接触层也降低了电解池与集流体之间的接触电阻,提高了电池电化学输出性能。 展开更多
关键词 固体氧化物电解池 阳极接触层 (Cu Mn)_(3)O_(4)尖晶石 反应烧结 面比电阻(ASR)
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Automatic Road Tunnel Crack Inspection Based on Crack Area Sensing and Multiscale Semantic Segmentation
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作者 Dingping Chen Zhiheng Zhu +1 位作者 Jinyang Fu Jilin He 《Computers, Materials & Continua》 SCIE EI 2024年第4期1679-1703,共25页
The detection of crack defects on the walls of road tunnels is a crucial step in the process of ensuring travel safetyand performing routine tunnel maintenance. The automatic and accurate detection of cracks on the su... The detection of crack defects on the walls of road tunnels is a crucial step in the process of ensuring travel safetyand performing routine tunnel maintenance. The automatic and accurate detection of cracks on the surface of roadtunnels is the key to improving the maintenance efficiency of road tunnels. Machine vision technology combinedwith a deep neural network model is an effective means to realize the localization and identification of crackdefects on the surface of road tunnels.We propose a complete set of automatic inspection methods for identifyingcracks on the walls of road tunnels as a solution to the problem of difficulty in identifying cracks during manualmaintenance. First, a set of equipment applied to the real-time acquisition of high-definition images of walls inroad tunnels is designed. Images of walls in road tunnels are acquired based on the designed equipment, whereimages containing crack defects are manually identified and selected. Subsequently, the training and validationsets used to construct the crack inspection model are obtained based on the acquired images, whereas the regionscontaining cracks and the pixels of the cracks are finely labeled. After that, a crack area sensing module is designedbased on the proposed you only look once version 7 model combined with coordinate attention mechanism (CAYOLOV7) network to locate the crack regions in the road tunnel surface images. Only subimages containingcracks are acquired and sent to the multiscale semantic segmentation module for extraction of the pixels to whichthe cracks belong based on the DeepLab V3+ network. The precision and recall of the crack region localizationon the surface of a road tunnel based on our proposed method are 82.4% and 93.8%, respectively. Moreover, themean intersection over union (MIoU) and pixel accuracy (PA) values for achieving pixel-level detection accuracyare 76.84% and 78.29%, respectively. The experimental results on the dataset show that our proposed two-stagedetection method outperforms other state-of-the-art models in crack region localization and detection. Based onour proposedmethod, the images captured on the surface of a road tunnel can complete crack detection at a speed often frames/second, and the detection accuracy can reach 0.25 mm, which meets the requirements for maintenanceof an actual project. The designed CA-YOLO V7 network enables precise localization of the area to which a crackbelongs in images acquired under different environmental and lighting conditions in road tunnels. The improvedDeepLab V3+ network based on lightweighting is able to extract crack morphology in a given region more quicklywhile maintaining segmentation accuracy. The established model combines defect localization and segmentationmodels for the first time, realizing pixel-level defect localization and extraction on the surface of road tunnelsin complex environments, and is capable of determining the actual size of cracks based on the physical coordinatesystemafter camera calibration. The trainedmodelhas highaccuracy andcanbe extendedandapplied to embeddedcomputing devices for the assessment and repair of damaged areas in different types of road tunnels. 展开更多
关键词 Road tunnel crack inspection crack area sensing multiscale semantic segmentation CA-YOLO V7 DeepLab V3+
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Application of 3-D Parallel Electrical Technology Detecting the Water-Rich Areas
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作者 Xuan Wang Liquan Guo 《Open Journal of Geology》 2014年第10期518-523,共6页
Coal working face is damaged more and more seriously by water below the coal face floor. Therefore, floor water detection is a must in the process of extraction. This article aims to introducing application and princi... Coal working face is damaged more and more seriously by water below the coal face floor. Therefore, floor water detection is a must in the process of extraction. This article aims to introducing application and principle of the two-gateways parallel 3-D electrical technology and the arrangement of the observation system. The authors use this method to detect the water under the floor of a mine in north of Anhui. The results show that the two-gateways parallel 3-D electrical technology can accurately locate the water-rich areas, providing the basis for drilling drainage and grouting construction. 展开更多
关键词 The Two-Gateways PARALLEL 3-D Electrical Technology Coal Face FLOOR Water-Rich areas
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合水地区长6_(3)深水重力流沉积特征研究
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作者 车雨恒 魏钦廉 +5 位作者 陈曦 田伟 李小军 张洪军 赵爱彬 唐婧 《石油地质与工程》 CAS 2024年第2期58-65,共8页
合水地区是鄂尔多斯盆地近年来原油勘探的重点区块,在系统分析沉积构造、岩石学特征、结构粒度特征等沉积相识别标志的基础上,结合区域沉积背景,开展了合水地区长6_(3)重力流沉积类型及展布特征研究。结果表明,合水地区长6_(3)油层亚组... 合水地区是鄂尔多斯盆地近年来原油勘探的重点区块,在系统分析沉积构造、岩石学特征、结构粒度特征等沉积相识别标志的基础上,结合区域沉积背景,开展了合水地区长6_(3)重力流沉积类型及展布特征研究。结果表明,合水地区长6_(3)油层亚组为湖泊-重力流沉积体系,发育半深湖-深湖沉积亚相,可进一步划分为浊流沉积、砂质碎屑流、滑塌沉积三种重力流沉积类型;其中砂质碎屑流及浊流为主要控砂微相,主要分布在研究区的中部、南部区域,为区内有利储集相带。 展开更多
关键词 鄂尔多斯盆地合水地区 长6_(3)油层亚组 重力流沉积 砂质碎屑流 浊流
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高密度城区绿地景观格局对PM_(2.5)/O_(3)的多尺度影响
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作者 马西娜 李金铭 +1 位作者 王梦媱 安琦 《西安建筑科技大学学报(自然科学版)》 北大核心 2024年第1期120-130,共11页
为探究高密度城区绿地景观格局对于PM_(2.5)浓度与O_(3)浓度的尺度效应,分析西安市高密度城区范围,选取边界密度(ED)、景观形状指数(LSI)、面积加权形状指数(SHAPE_AM)和平均形状指数(SHAPE_MN)共4个景观格局指数衡量绿地景观格局,爬取2... 为探究高密度城区绿地景观格局对于PM_(2.5)浓度与O_(3)浓度的尺度效应,分析西安市高密度城区范围,选取边界密度(ED)、景观形状指数(LSI)、面积加权形状指数(SHAPE_AM)和平均形状指数(SHAPE_MN)共4个景观格局指数衡量绿地景观格局,爬取2020—2021年国家空气质量监测站点的大气监测数据,运用皮尔逊相关性分析和线性回归分析方法,探究多尺度下高密度城区绿地景观格局对PM_(2.5)和O_(3)的时空分布特征、绿地景观格局特征和PM_(2.5)浓度、O_(3)浓度与景观格局指数的多尺度影响关系.结果表明,景观格局在夏季对于PM_(2.5)浓度、在春季对于O_(3)浓度的影响更为显著;在高密度城区内较小尺度的绿地上优化景观格局对PM_(2.5)与O_(3)浓度影响更有效.由此提出的绿地优化策略可为城市高密度城区多尺度绿地规划设计提供参考依据. 展开更多
关键词 城市高密度城区 多尺度效应 绿地景观格局 PM_(2.5) O_(3)
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高比表面积α-Al_(2)O_(3)在催化剂中的应用及展望
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作者 王冉 《浙江化工》 CAS 2024年第4期26-31,共6页
高比表面积α-Al_(2)O_(3)在室温下为热力学不稳定相,合成难度较大。但其表面惰性、机械强度高、水热稳定性高且对活性金属的分散能力强,使其在催化剂载体应用领域具有重要优势。本文总结了高比表面积α-Al_(2)O_(3)制备方法的最新研究... 高比表面积α-Al_(2)O_(3)在室温下为热力学不稳定相,合成难度较大。但其表面惰性、机械强度高、水热稳定性高且对活性金属的分散能力强,使其在催化剂载体应用领域具有重要优势。本文总结了高比表面积α-Al_(2)O_(3)制备方法的最新研究进展,介绍了其在催化剂中的应用实例。根据材料特性,对α-Al_(2)O_(3)作为催化剂载体可应用的潜在反应类型进行了展望,为其后续研发和应用提供参考。 展开更多
关键词 高比表面积 纳米α-Al_(2)O_(3) 催化应用 氧化铝载体 刚玉
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血清CHI3L1水平与2型糖尿病合并代谢相关脂肪性肝病患者的相关性分析
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作者 杨静 王艳娇 《转化医学杂志》 2024年第3期388-391,共4页
目的 探讨血清壳多糖酶3样蛋白1(CHI3L1)水平与2型糖尿病(T2DM)患者合并代谢相关脂肪性肝病(MAFLD)的关系。方法 按照1∶1比例选取2020年1月至2023年12月河北省唐山南湖医院收治的T2DM合合并MAFLD患者(MAFLD组)和未合并MAFLD的T2DM患者(... 目的 探讨血清壳多糖酶3样蛋白1(CHI3L1)水平与2型糖尿病(T2DM)患者合并代谢相关脂肪性肝病(MAFLD)的关系。方法 按照1∶1比例选取2020年1月至2023年12月河北省唐山南湖医院收治的T2DM合合并MAFLD患者(MAFLD组)和未合并MAFLD的T2DM患者(非MAFLD组)各120例,采用酶联免疫吸附法检测2组患者血清CHI3L1水平,并收集2组患者基线资料。采用多因素条件Logistic回归模型分析CHI3L1与T2DM患者合并MAFLD的关系,绘制受试者工作特征(ROC)曲线,分析CHI3L1对T2DM合并MAFLD的预测价值。结果 与非MAFLD组比较,MAFLD组血清CHI3L1水平升高(P <0.05)。调整混杂因素后,CHI3L1升高为T2DM患者合并MAFLD的独立危险因素(P <0.05)。血清CHI3L1水平预测T2DM患者合并MAFLD的曲线下面积(AUC)为0.803,敏感度为70.83%,特异度为88.33%。结论 T2DM患者血清CHI3L1水平升高是合并MAFLD的独立危险因素,并对T2DM患者合并MAFLD具有一定的预测价值。 展开更多
关键词 糖尿病 2型 代谢相关脂肪性肝病 壳多糖酶3样蛋白1 Logistic模型 ROC曲线 曲线下面积
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武汉城市圈O_(3)时空特征及气象因素的影响 被引量:2
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作者 王骏星 陈进 +3 位作者 成海容 陈楠 詹领茜 杜清运 《环境科学与技术》 CAS CSCD 北大核心 2023年第5期142-151,共10页
文章基于2015-2020年武汉城市圈81个国控点和省控点空气自动站的臭氧监测数据,分析了武汉城市圈臭氧浓度的时空分布特征以及与典型气象因子的相关性。结果表明:时间上,2015-2017年武汉城市圈臭氧年均浓度和超标天数逐步下降,至2017年达... 文章基于2015-2020年武汉城市圈81个国控点和省控点空气自动站的臭氧监测数据,分析了武汉城市圈臭氧浓度的时空分布特征以及与典型气象因子的相关性。结果表明:时间上,2015-2017年武汉城市圈臭氧年均浓度和超标天数逐步下降,至2017年达到低点。2018年开始快速上升,至2019年达到峰值。之后由于新冠疫情的影响,2020年臭氧浓度和超标天数均有所下降。空间上,武汉城市圈臭氧年均浓度整体东部城市高于西部汉江平原城市,并在较高臭氧浓度范围内其空间分布差别不大。武汉城市圈臭氧浓度与湿度(>25%时)、气压、降水量呈负相关关系,与温度呈正相关关系。城市站点臭氧浓度高值大多出现在低风速时期(<4 m/s)。就风向而言,鄂州、黄冈、黄石、潜江、天门、仙桃、孝感站点臭氧的8 h浓度高值大多出现在南风,特别是东南风。咸宁站点臭氧高值时风向分布较为分散,而武汉市臭氧高值主要出现在西北风和东北风情形。 展开更多
关键词 武汉城市圈 O_(3) 时空分布 气象因素
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西北部欠发达地区0-3岁婴幼儿托育服务需求研究 被引量:3
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作者 杨琴 宫敏 《湖北师范大学学报(哲学社会科学版)》 2023年第2期127-133,共7页
本研究通过对西北A省婴幼儿家庭的托育意愿、托育服务的具体需求和政府层面的育儿支持服务三方面的调查发现,欠发达地区家庭的婴幼儿送托意愿较为强烈,对公办、全日制的托育机构需求较大,比较重视托育机构的安全防护、卫生保健和饮食保... 本研究通过对西北A省婴幼儿家庭的托育意愿、托育服务的具体需求和政府层面的育儿支持服务三方面的调查发现,欠发达地区家庭的婴幼儿送托意愿较为强烈,对公办、全日制的托育机构需求较大,比较重视托育机构的安全防护、卫生保健和饮食保障,倾向于婴幼儿在托育中的性格和习惯培养,希望托育园所教师具备专业背景且保持较低的流动性,期望政府层面提高家庭养育补助金、增加育儿带薪假以及允许父母灵活安排育儿假等。基于此,本研究认为加快发展普惠性托育机构、推进托育服务向社区下沉、加强托育机构监管、支持托育专业人才培养以及为家庭提供多样化的育儿福利政策可以较好地满足家庭的托育需求。 展开更多
关键词 0-3岁婴幼儿 托育需求 欠发达地区
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纳米晶PbTiO_3负载CuO催化NO分解 被引量:1
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作者 邢丽 薛念华 +3 位作者 陈向科 郭学锋 丁维平 陈懿 《无机化学学报》 SCIE CAS CSCD 北大核心 2005年第5期729-732,共4页
A large specific surface area perovskite-type mixed oxide PbTiO3 supported cupric oxide was synthesized as a catalyst for NO decomposition and characterized by techniques such as XPS, XRD, H2-TPR before and after NO d... A large specific surface area perovskite-type mixed oxide PbTiO3 supported cupric oxide was synthesized as a catalyst for NO decomposition and characterized by techniques such as XPS, XRD, H2-TPR before and after NO decomposition reactions. The catalytic properties were tested with a fix-bed micro-reactor. The results showed that the PbTiO3 was inactive for the reactions, but 1wt % Cu/PbTiO3 catalyst gave fairly good activities for NO decomposition at temperature as low as 473 K. Copper species were found well-dispersed but weakly interacted with the support before NO decomposition, and the NO decomposition caused significant change in the environment of the copper species, which became Cu(Ⅰ)and most probably incorporated into surface crystal lattice of the nano-sized PbTiO3. In NO reaction, a large amount of oxygen atoms from the decomposition of NO penetrated into the nano-sized PbTiO3 support and caused small expansion of crystal lattice. The transport of oxygen between the copper species and the catalyst support may be helpful to speed up the kinetic regeneration of active metal sites from oxygen occupancy and resulted in good catalytic performance. 展开更多
关键词 PBTIO3 catalyst surface crystal CUO 纳米晶 transport performa lattice 分解 催化 负载 active the with and after Cu(Ⅰ) small speed metal The area MOST was XPS XRD MAY in be
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中医基础课程3×3教学模式的构建与探索——以中医各家学说课程为例 被引量:1
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作者 刘成丽 李剑 《新中医》 CAS 2023年第24期234-238,共5页
中医各家学说是中医基础课程中的临床基础课,对学生中医思维模式的培养和能力的提高具有重要意义。课程教学团队在“粤港澳高校中医药基础课程教育联盟”基础上,更新教育教学理念、整合课程内容体系,探索构建了全过程贯穿式、全方位多... 中医各家学说是中医基础课程中的临床基础课,对学生中医思维模式的培养和能力的提高具有重要意义。课程教学团队在“粤港澳高校中医药基础课程教育联盟”基础上,更新教育教学理念、整合课程内容体系,探索构建了全过程贯穿式、全方位多元化、多层次递进式的中医基础课程3×3教学新模式。从教育现状、课程建设、新模式的内涵和实施方案等方面介绍3×3教学模式,以期为其他中医基础课程提供借鉴。 展开更多
关键词 中医各家学说 粤港澳大湾区 粤港澳高校中医药基础课程教育联盟 3×3教学模式 教学改革
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B4C对Si3N4/Si_(2)N_(2)O结合SiC材料抗热震性能的影响
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作者 曹会彦 吴吉光 +2 位作者 程竹 李杰 黄志刚 《耐火材料》 CAS 北大核心 2023年第1期70-73,共4页
首先以Si粉、SiO_(2)微粉为原料,先在700℃空气气氛处理,然后在1400℃氮气气氛下合成Si_(2)N_(2)O,研究了B_(4)C添加量(外加质量分数分别为0、1.0%、2.0%、3.0%、4.0%)对Si_(2)N_(2)O合成效果的影响。然后根据B_(4)C最优加入量,先在700... 首先以Si粉、SiO_(2)微粉为原料,先在700℃空气气氛处理,然后在1400℃氮气气氛下合成Si_(2)N_(2)O,研究了B_(4)C添加量(外加质量分数分别为0、1.0%、2.0%、3.0%、4.0%)对Si_(2)N_(2)O合成效果的影响。然后根据B_(4)C最优加入量,先在700℃空气气氛保温5 h,然后在1400℃氮气气氛保温5 h制备了Si_(3)N_(4)/Si_(2)N_(2)O结合SiC试样。采用1300℃风冷5次后试样的抗折强度保持率评价其抗热震性,分析了热震前后试样的物相组成和显微结构。结果表明:1)合成Si_(2)N_(2)O的B_(4)C最优添加量为3%(w);在700℃空气处理时,B_(4)C优先和气氛中O_(2)反应生成液相B2O3,为1400℃氮气气氛生成板片状Si_(2)N_(2)O提供充足液相。2)风冷热震后,添加B_(4)C的试样中Si_(2)N_(2)O结合相保持完整,强度保持率由未添加时的67.5%提高至88.5%;同时,生成的B2O3发生碳热还原氮化反应,生成导热性好、具有自润滑特性的BN,改善其抗热震性,并在使用过程中继续为Si_(3)N_(4)/Si_(2)N_(2)O结合SiC材料提供保护。 展开更多
关键词 B_(4)C Si_(3)N_(4)/Si_(2)N_(2)O结合SiC 抗热震性 干熄炉 斜道区
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Hydrogen production from steam reforming of methanol over CuO/ZnO/Al_2O_3 catalysts: Catalytic performance and kinetic modeling 被引量:8
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作者 Yu Wan Zhiming Zhou Zhenmin Cheng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第9期1186-1194,共9页
A series of CuO/ZnO/Al_2O_3, CuO/ZnO/ZrO_2/Al_2O_3 and CuO/ZnO/CeO_2/Al_2O_3 catalysts were prepared by coprecipitation and characterized by N_2 adsorption, XRD, TPR, N_2O titration and HRTEM. The catalytic performanc... A series of CuO/ZnO/Al_2O_3, CuO/ZnO/ZrO_2/Al_2O_3 and CuO/ZnO/CeO_2/Al_2O_3 catalysts were prepared by coprecipitation and characterized by N_2 adsorption, XRD, TPR, N_2O titration and HRTEM. The catalytic performances of these catalysts for the steam reforming of methanol were evaluated in a laboratory-scale fixed-bed reactor at 0.1 MPa and temperatures between 473 and 543 K. The results showed that the catalytic activity depended greatly on the catalyst reducibility and the specific surface area of Cu. An approximate linear correlation between the catalytic activity and the Cu surface area was found for all catalysts investigated in this study.Compared to CuO/ZnO/Al_2O_3, the ZrO_2-doped CuO/ZnO/Al_2O_3 exhibited higher activity and selectivity to CO,while the CeO_2-doped catalyst displayed lower activity and selectivity. Finally, an intrinsic kinetic study was carried out over a screened CuO/ZnO/CeO_2/Al_2O_3 catalyst in the absence of internal and external mass transfer effects. A good agreement was observed between the model-derived effluent concentrations of CO(CO_2) and the experimental data. The activation energies for the reactions of methanol-steam reforming, water-gas shift and methanol decomposition over CuO/ZnO/CeO_2/Al_2O_3 were 93.1, 85.1 and 116.5 k J·mol^(-1), respectively. 展开更多
关键词 Steam reforming of methanol CuO/Zno/Al2O3 DOPANTS Cu surface area KINETICS
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Metal-Free C_(3)N_(4) with plentiful nitrogen vacancy and increased specific surface area for electrocatalytic nitrogen reduction 被引量:5
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作者 Ziming Zhao Yu Long +3 位作者 Sha Luo Yutong Luo Ming Chen Jiantai Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第9期546-555,共10页
As a substitute for synthetic ammonia under mild condition, electrocatalytic nitrogen reduction reaction(NRR) provides a hopeful approach for the development of ammonia. Nevertheless, the current development of NRR el... As a substitute for synthetic ammonia under mild condition, electrocatalytic nitrogen reduction reaction(NRR) provides a hopeful approach for the development of ammonia. Nevertheless, the current development of NRR electrocatalysts is far from enough and a systematic research is needed to gain a better improvement. This article presents that 2 D C_(3)N_(4)-NV with a large specific surface area and abundant nitrogen vacancies is prepared by a simple and feasible method, and used as a metal-free catalyst for electrocatalytic NRR. Experiment result and density functional theory(DFT) calculation reveal that nitrogen vacancies in 2 D C_(3)N_(4)-NV can act as an efficient active site for catalytic NRR, which is conducive to capturing and activating N_(2), lowering Gibbs free energy(DG) in reaction and inhibiting hydrogen evolution reaction(HER) at the same time. In addition, the larger specific surface area also makes more active site exposed, which is good for the contact between the electrolyte and the active site, thus enhancing its NRR activity. The electrocatalyst shows an excellent catalytic activity for NRR in 0.1 M HCl, including Faradaic efficiency of 10.96%, NH_(3) yields of 17.85 lg h^(-1) mg_(cat)^(-1)., and good stability(over 20 h). 展开更多
关键词 2D C_(3)N_(4)-NV Larger specific surface area Nitrogen vacancy Electrocatalyst NRR
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