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Geographic Drone-based Route Optimization Approach for Emergency Area Ad-Hoc Network
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作者 V.Krishnakumar R.Asokan 《Computer Systems Science & Engineering》 SCIE EI 2023年第4期985-1000,共16页
Wireless sensor Mobile ad hoc networks have excellent potential in moving and monitoring disaster area networks on real-time basis.The recent challenges faced in Mobile Ad Hoc Networks(MANETs)include scalability,local... Wireless sensor Mobile ad hoc networks have excellent potential in moving and monitoring disaster area networks on real-time basis.The recent challenges faced in Mobile Ad Hoc Networks(MANETs)include scalability,localization,heterogeneous network,self-organization,and self-sufficient operation.In this background,the current study focuses on specially-designed communication link establishment for high connection stability of wireless mobile sensor networks,especially in disaster area network.Existing protocols focus on location-dependent communications and use networks based on typically-used Internet Protocol(IP)architecture.However,IP-based communications have a few limitations such as inefficient bandwidth utilization,high processing,less transfer speeds,and excessive memory intake.To overcome these challenges,the number of neighbors(Node Density)is minimized and high Mobility Nodes(Node Speed)are avoided.The proposed Geographic Drone Based Route Optimization(GDRO)method reduces the entire overhead to a considerable level in an efficient manner and significantly improves the overall performance by identifying the disaster region.This drone communicates with anchor node periodically and shares the information to it so as to introduce a drone-based disaster network in an area.Geographic routing is a promising approach to enhance the routing efficiency in MANET.This algorithm helps in reaching the anchor(target)node with the help of Geographical Graph-Based Mapping(GGM).Global Positioning System(GPS)is enabled on mobile network of the anchor node which regularly broadcasts its location information that helps in finding the location.In first step,the node searches for local and remote anticipated Expected Transmission Count(ETX),thereby calculating the estimated distance.Received Signal Strength Indicator(RSSI)results are stored in the local memory of the node.Then,the node calculates the least remote anticipated ETX,Link Loss Rate,and information to the new location.Freeway Heuristic algorithm improves the data speed,efficiency and determines the path and optimization problem.In comparison with other models,the proposed method yielded an efficient communication,increased the throughput,and reduced the end-to-end delay,energy consumption and packet loss performance in disaster area networks. 展开更多
关键词 Mobile ad hoc networks(MANETs) geographical graph-based mapping(GGM) geographic drone based route optimization data speed anchor node’s
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BIODRILL S合成基钻井液在垦利区块首次应用
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作者 彭三兵 李斌 +3 位作者 韩东东 徐磊 程龙生 黄贤斌 《钻井液与完井液》 CAS 北大核心 2024年第1期60-67,共8页
渤海油田垦利9-1区块地层岩性复杂,且存在断层带,钻井过程中易发生泥岩水化分散和砂岩层井眼缩径等问题,井壁垮塌风险极大。针对该区块地层岩性特点和技术难题并结合环保要求,制备了一种复合型封堵材料PFMOSHIELD,构建了BIODRILL S合成... 渤海油田垦利9-1区块地层岩性复杂,且存在断层带,钻井过程中易发生泥岩水化分散和砂岩层井眼缩径等问题,井壁垮塌风险极大。针对该区块地层岩性特点和技术难题并结合环保要求,制备了一种复合型封堵材料PFMOSHIELD,构建了BIODRILL S合成基钻井液体系。该体系流变性能良好,抗钙、抗岩屑污染达26%和15%,封堵性、沉降稳定性、润滑性优异,高温高压砂盘滤失量3.2 mL,静置7 d沉降因子为0.53,极压润滑系数0.082。BIODRILL S首次在渤海湾垦利9-1区块进行了现场应用,结果表明:该体系解决了垦利9-1区块泥页岩水化和砂岩层井眼缩径问题,垦利9-1北-3定向探井三开井段上部地层钻屑完整,钻屑达4~7 cm;井眼清洁性能良好,钻井液动塑比超过0.59 Pa/mPa·s,φ6和φ3读数均超过9,剪切稀释性强,提高了井眼净化效率,有效避免形成“岩屑床”;润滑性能优异,在大井斜段(55°、70°、67°)可实现直接起钻。 展开更多
关键词 合成基钻井液 BIODRILL s 渤海油田 垦利区块
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COVID-19 mortality paradox(United States vs Africa):Mass vaccination vs early treatment
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作者 Mina Thabet Kelleni 《World Journal of Experimental Medicine》 2024年第1期6-12,共7页
The coronavirus disease 2019(COVID-19)mortality rate in 55 African countries is almost 4.5 times lower than in the coronavirus disease 2019(COVID-19)despite Africa having over 4.2 times more people.This mortality para... The coronavirus disease 2019(COVID-19)mortality rate in 55 African countries is almost 4.5 times lower than in the coronavirus disease 2019(COVID-19)despite Africa having over 4.2 times more people.This mortality paradox is also evident when comparing Nigeria,a heavily populated,poorly vaccinated and weakly mandated country to Israel,a small,highly vaccinated and strictly mandated country.Nigeria has almost 4 times lower COVID mortality than Israel.In this Field of Vision perspective,I explain how this paradox has evolved drawing upon my academic,clinical and social experience.Since April 2020,I’ve developed and been using the Egyptian immune-modulatory Kelleni’s protocol to manage COVID-19 patients including pediatric,geriatric,pregnant,immune-compromised and other individuals suffering from multiple comorbidities.It’s unfortunate that severe acute respiratory syndrome coronavirus 2 is still evolving accompanied by more deaths.However in Africa,we’ve been able to live without anxiety or mandates throughout the pandemic because we trust science and adopted early treatment using safe,and effective repurposed drugs that have saved the majority of COVID-19 patients.This article represents an African and Egyptian tale of honor. 展开更多
关键词 COVID-19 Early treatment Kelleni’s Protocol Mandates Mortality Paradox sARs-CoV-2 Nucleic acid based vaccines
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观察基于Watson人性照顾理论的干预对重症肺炎合并呼吸衰竭患者的应用效果
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作者 王宝玉 《世界睡眠医学杂志》 2024年第5期1173-1176,共4页
目的:观察基于Watson人性照顾理论的干预对重症肺炎合并呼吸衰竭患者的应用效果。方法:选取2021年6月至2023年6月泉州市第一医院呼吸与危重症医学科收治的重症肺炎合并呼吸衰竭患者94例作为研究对象,按照随机数字表法分为对照组和观察组... 目的:观察基于Watson人性照顾理论的干预对重症肺炎合并呼吸衰竭患者的应用效果。方法:选取2021年6月至2023年6月泉州市第一医院呼吸与危重症医学科收治的重症肺炎合并呼吸衰竭患者94例作为研究对象,按照随机数字表法分为对照组和观察组,每组47例。对照组给予常规护理干预,观察组在对照组基础上给予Watson人性照顾理论的干预。采用匹兹堡睡眠质量指数量表(PSQI)比较2组患者干预前后睡眠质量的变化,采用阿森斯失眠量表(AIS)评估2组患者干预前后失眠的改善效果,并通过2组患者护理后的呼吸困难缓解时间、机械通气时间、重症监护室住院时间,以判断恢复情况。结果:干预后,观察组患者PSQI评分、AIS评分均显著低于对照组,观察组呼吸困难缓解时间、机械通气时间及重症监护室住院时间均显著短于对照组,差异均有统计学意义(均P<0.05)。结论:对重症肺炎合并呼吸衰竭患者应用基于Watson人性照顾理论的护理干预可有效改善其睡眠质量,促进病情恢复,值得临床推广应用。 展开更多
关键词 基于Watson人性照顾理论的干预 重症肺炎 呼吸衰竭 睡眠质量 重症护理
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载铜地质聚合物微球的制备及其催化降解双酚S的性能
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作者 张政 刘琳 +3 位作者 李子晨 王梦琦 黄春燕 葛圆圆 《化工进展》 EI CAS CSCD 北大核心 2024年第9期5290-5301,共12页
传统的芬顿反应因在废水处理过程中会产生大量富含金属污泥而应用受限。本研究采用悬浮固化法得到了一种低成本、易回收、绿色的多孔地质聚合物微球(GM),将其作为载体通过浸渍法制备了载铜地质聚合物微球(Cu-GM),作为类芬顿反应催化剂,... 传统的芬顿反应因在废水处理过程中会产生大量富含金属污泥而应用受限。本研究采用悬浮固化法得到了一种低成本、易回收、绿色的多孔地质聚合物微球(GM),将其作为载体通过浸渍法制备了载铜地质聚合物微球(Cu-GM),作为类芬顿反应催化剂,催化H_(2)O_(2)降解水中的双酚S(BPS)。SEM、XRD、BET和XPS等一系列表征结果表明,Cu^(+/2+)被稳定固定在GM表面。进一步探究了Cu-GM用量、H_(2)O_(2)用量、BPS浓度和溶液初始p H对催化降解的影响。结果表明,在优化条件下,Cu-GM在480min内对BPS的去除率可达99.3%,催化降解过程符合一级反应动力学。通过自由基淬灭实验发现,在催化降解过程中·OH和^(1)O_(2)是主要活性物质。循环实验表明Cu-GM具有良好的重复利用性,在去除水中有机污染物方面有着极大的应用潜力。 展开更多
关键词 地质聚合物微球 铜基类芬顿 双酚s 催化降解 降解机理
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基于密度泛函理论的S掺杂碳载体负载Pt催化剂对氧还原反应的影响
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作者 叶蔚甄 任强 +1 位作者 王春璐 曲亚坤 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第4期931-941,共11页
采用密度泛函方法对比研究了Pt/C催化剂中碳载体掺S前后对氧还原反应(ORR)的影响。从电荷分布、态密度及d带中心等性质出发,分析了金属-载体间相互作用,研究了ORR各物种在催化剂上的吸附并计算了ORR过电势。结果表明:S掺杂使得碳载体表... 采用密度泛函方法对比研究了Pt/C催化剂中碳载体掺S前后对氧还原反应(ORR)的影响。从电荷分布、态密度及d带中心等性质出发,分析了金属-载体间相互作用,研究了ORR各物种在催化剂上的吸附并计算了ORR过电势。结果表明:S掺杂使得碳载体表面发生了电子转移,S上的电子转移到邻近的C原子上,负载Pt纳米颗粒后,Pt金属上的电子转移给了碳载体;Pt在S掺杂碳载体上的吸附更强,形成了Pt—C键和Pt—S键,Pt纳米颗粒的分散度和稳定性得到了提升;掺S使得催化剂d带中心下降,对ORR各中间体的吸附减弱,ORR过电势降低,表明掺S能提高催化剂的催化活性。 展开更多
关键词 s掺杂 Pt基催化剂 氧还原反应 密度泛函理论 态密度 d带中心 过电势
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CO_(2)和H_(2)S对镍基合金028点蚀敏感性及点蚀生长动力学的影响
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作者 席文强 孙冲 +2 位作者 樊学华 林学强 孙建波 《表面技术》 EI CAS CSCD 北大核心 2024年第16期78-88,102,共12页
目的探明CO_(2)和H_(2)S对镍基合金028钝化膜性能和点蚀敏感性的影响。方法采用循环动电位极化(CPP)、电化学阻抗谱(EIS)、莫特-肖特基(M-S)等测试方法,研究Cl-环境、CO_(2)-Cl-环境和H_(2)S-Cl-环境中镍基合金028的钝化膜性能。通过制... 目的探明CO_(2)和H_(2)S对镍基合金028钝化膜性能和点蚀敏感性的影响。方法采用循环动电位极化(CPP)、电化学阻抗谱(EIS)、莫特-肖特基(M-S)等测试方法,研究Cl-环境、CO_(2)-Cl-环境和H_(2)S-Cl-环境中镍基合金028的钝化膜性能。通过制备一维人工凹坑电极模拟点蚀坑的稳态生长,采用向负向电位扫描法,研究镍基合金028在局部点蚀环境中的金属溶解动力学,明确CO_(2)和H_(2)S对点蚀生长动力学的影响。结果CO_(2)和H_(2)S都会使镍基合金028钝化膜性能变差,而H_(2)S的影响更为显著,具体表现为:在H_(2)S-Cl-环境中具有更高的钝化电流密度jp、更低的点蚀电位Eb和再钝化电位Erp。H_(2)S-Cl-环境中的钝化膜电阻Rf、电荷转移电阻Rt和钝化膜厚度均低于CO_(2)-Cl-环境中的,此外,钝化膜在H_(2)S-Cl-环境中具有更高的点缺陷密度。在最大点蚀坑溶解电流密度jdiss,max相同的条件下,H_(2)S-Cl-环境中点蚀稳态生长所需的驱动力Emax明显低于CO_(2)-Cl-环境中的;在相同Emax下,H_(2)S-Cl-环境中的jdiss,max高于CO_(2)-Cl-环境中的。结论CO_(2)和H_(2)S通过增加钝化膜溶解速率、降低钝化膜电阻和增加点缺陷密度,不同程度地增加了镍基合金028的点蚀敏感性,而H_(2)S更容易造成钝化膜损伤。在点蚀稳态生长阶段,镍基合金028点蚀的稳态生长遵循塔菲尔规律,相比于CO_(2),H_(2)S更容易促进点蚀从亚稳态向稳态发展,并且在H_(2)S环境中具有更高的点蚀生长稳定性。 展开更多
关键词 镍基合金 CO_(2) H_(2)s 点蚀敏感性 一维人工凹坑电极 点蚀生长动力学
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HRB400级钢筋母材疲劳性能试验及P-S-N曲线确定
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作者 李鑫 《建筑技术开发》 2024年第7期135-138,共4页
针对HRB400、HRBF4002种型号及16 mm、20 mm、25 mm、32 mm 4种不同直径的钢筋母材,研究了高强钢筋母材疲劳性能的试验,其应力比为0.4。通过试验结果对比分析不同直径对钢筋疲劳性能的影响,利用数据统计方法对试验结果进行了统计分析并... 针对HRB400、HRBF4002种型号及16 mm、20 mm、25 mm、32 mm 4种不同直径的钢筋母材,研究了高强钢筋母材疲劳性能的试验,其应力比为0.4。通过试验结果对比分析不同直径对钢筋疲劳性能的影响,利用数据统计方法对试验结果进行了统计分析并获得了S-N和P-S-N曲线。试验结果表明:对于HRB400与HRBF4002种型号的钢筋来说,其均具有随钢筋直径增大,钢筋母材的疲劳性能不断降低的规律;对比HRB400与HRBF4002种型号的钢筋母材疲劳性能发现,HRBF400级钢筋母材疲劳性能优于HRB400级;分析HRB400与HRBF4002种型号高强钢筋不同直径的总体数据样本,发现400级高强钢筋在中长寿命区的m值约为5.346,同时确定了总体样本下的P-S-N曲线,为400级高强钢筋在后续的疲劳设计及工程建设等方面提供了理论参考。 展开更多
关键词 HRB400级钢筋母材 HRBF400级钢筋母材 疲劳性能 P-s-N曲线
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“共享、联动、创生”:U-G-S框架下的集团化办学创新探索——以上海师范大学嘉定基础教育集团为例
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作者 吴宝英 《现代基础教育研究》 2024年第3期38-42,共5页
促进优质均衡发展,推进学区化集团化办学,是上海深化基础教育领域综合改革、积极回应人民群众接受高质量教育需求的重要举措。以“共享、联动、创生”为主旨,上海师范大学嘉定基础教育集团进行了U-G-S框架背景下的新型集团化办学创新探... 促进优质均衡发展,推进学区化集团化办学,是上海深化基础教育领域综合改革、积极回应人民群众接受高质量教育需求的重要举措。以“共享、联动、创生”为主旨,上海师范大学嘉定基础教育集团进行了U-G-S框架背景下的新型集团化办学创新探索,逐步积累了U-G-S框架下的集团愿景共享、重大项目联动、龙头课题创生等方面的经验,并取得了初步成效。 展开更多
关键词 集团化办学 U-G-s框架 创新探索
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新型多取代Trger’s base衍生物的合成及其晶体结构 被引量:1
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作者 李正义 庄跃 +2 位作者 朱美兰 殷乐 孙小强 《合成化学》 CAS CSCD 2017年第8期629-636,共8页
以邻氨基二苯甲酮为原料,经两分子环化缩合反应制得6,12-二芳基二苯并[b,f][1,5]二氮杂环辛四烯(2a^2d);2a^2d经Li Al H4还原制得6,12-二芳基-5,6,11,12-四氢二苯并[b,f][1,5]二氮杂环辛(3a^3d);3a^3d与醛(或酮)反应,合成了一系列新型... 以邻氨基二苯甲酮为原料,经两分子环化缩合反应制得6,12-二芳基二苯并[b,f][1,5]二氮杂环辛四烯(2a^2d);2a^2d经Li Al H4还原制得6,12-二芳基-5,6,11,12-四氢二苯并[b,f][1,5]二氮杂环辛(3a^3d);3a^3d与醛(或酮)反应,合成了一系列新型的多取代Trger’s base衍生物(4a^4d和5a^7a),其结构经1H NMR,13C NMR,HR-MS(ESI)和X-射线单晶衍射表征。通过分析架桥前后3a(CCDC:1498564)和6a(CCDC:1498555)的晶体结构,解释了该类化合物1H NMR中NCH质子及桥上取代基质子裂分的原因,并进一步证实了4~7为非C2轴对称结构。 展开更多
关键词 多取代Troger’s base衍生物 合成 晶体结构 质子裂分
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基于Faster R-CNN的密集人群检测算法 被引量:4
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作者 邹斌 张聪 《计算机应用》 CSCD 北大核心 2023年第1期61-66,共6页
为提高拥挤场景下的人群检测准确率,提出一种基于改进Faster R-CNN的密集人群检测算法。首先,在特征提取阶段添加空间与通道注意力机制,使用加强的双向特征金字塔网络(S-BiFPN)替代原网络中的多尺度特征金字塔(FPN),使网络对重要特征进... 为提高拥挤场景下的人群检测准确率,提出一种基于改进Faster R-CNN的密集人群检测算法。首先,在特征提取阶段添加空间与通道注意力机制,使用加强的双向特征金字塔网络(S-BiFPN)替代原网络中的多尺度特征金字塔(FPN),使网络对重要特征进行自主学习并加强对图像深层特征的提取;其次,引入多实例预测(MIP)算法对实例进行预测,以避免模型对拥挤场景下的目标造成漏检;最后,对模型中的非极大值抑制(NMS)进行优化,并额外增设一个交并比(IoU)阈值,以对检测结果的干扰项进行精确抑制。在开源的密集人群检测数据集上进行测试的结果显示,相较于原Faster R-CNN算法,所提算法的平均精度(AP)提升5.6%,Jaccard指数值提升3.2%。所提算法具有较高检测精度和稳定性,可以满足密集场景人群检测的需求。 展开更多
关键词 密集人群检测 Faster R-CNN 注意力机制 多实例预测 加强的双向特征金字塔网络
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Li_(2)S掺杂对富锂锰基材料首次库仑效率的提升效果研究
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作者 陈垒 王皓 +3 位作者 张文慧 洪灿灿 王点点 赵金安 《化工新型材料》 CAS CSCD 北大核心 2023年第4期175-178,190,共5页
富锂锰基材料(LRM)由于电压平台高、比容量高,在锂电池材料研究中受到广泛关注。针对富锂锰基材料首次充放电库仑效率较低的问题,采用Li_(2)S对富锂锰基材料(LRM)进行掺杂改性制备得到LRM-S材料。结果表明:LRM和LRM-S的晶体结构相近,具... 富锂锰基材料(LRM)由于电压平台高、比容量高,在锂电池材料研究中受到广泛关注。针对富锂锰基材料首次充放电库仑效率较低的问题,采用Li_(2)S对富锂锰基材料(LRM)进行掺杂改性制备得到LRM-S材料。结果表明:LRM和LRM-S的晶体结构相近,具有层状晶体结构。扫描电镜分析表明,LRM-S材料由10~20nm的一次颗粒团聚而成。元素分析表明LRM-S材料中含有均匀分散的S元素。电化学分析表明,LRM的首次充电比容量为291.80mAh/g,首次放电比容量为188.63mAh/g,首次库仑效率为64.64%。Li_(2)S掺杂改性材料LRM-S的首次充电比容量为387.04mAh/g,首次放电比容量为272.64mAh/g,首次库仑效率为70.44%,在首次充放电比容量和效率方面均有显著提升。 展开更多
关键词 富锂锰基 Li_(2)s 掺杂改性 首次库仑效率 电化学性能测试
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Urban Construction Land Suitability Evaluation Based on Improved Multi-criteria Evaluation Based on GIS(MCE-GIS): Case of New Hefei City,China 被引量:23
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作者 ZHANG Xiaorui FANG Chuanglin +1 位作者 WANG Zhenbo MA Haitao 《Chinese Geographical Science》 SCIE CSCD 2013年第6期740-753,共14页
Urban construction land suitability evaluation (UCLSE) is a complex system engineering and the basis for rational use of the limited urban land resources in China. It has an important practical value on urban constr... Urban construction land suitability evaluation (UCLSE) is a complex system engineering and the basis for rational use of the limited urban land resources in China. It has an important practical value on urban construction land use planning and management from the angle of methodology. As a widely used technique, traditional multi-criteria evaluation based on GIS (MCE-GIS), is not suitable for UCLSE. This study develops an improved MCE-GIS method which could be more suitable for UCLSE based on urban complex ecological system theory and the summary of the shortcomings of traditional MCE-GIS. The improvements include three aspects: a composite evaluation index system rather than natural indexes alone, an index weight calculated by using fuzzy Analytic Hierarchy Process (AHP) method rather than the common AHP method, and the integrated overlay rule, which includes selecting the minimum value, weighted linear combination (WLC) and simple summation. The main advantage of this improved technique is that it can make UCLSE more comprehensive, more operational and more reasonable. It can provide a scientific basis for decision making in the planning and management of urban construction land use. The improved MCE-GIS system has been adopted in the New Hefei City, Anhui Province, China. Based on the results of UCLSE in New Hefei, three functional areas including construction-appropriate areas, construction-restricted areas and construction-forbidden areas could be worked out, in which 36.90% of the total study area could be developed as urban construction land and the remaining 63.10% should be protected as reserves land or as ecological land. Furthermore, the results can orovide scientific decision suooort for spatial planning and eco-environment nrotection in New Hefei. 展开更多
关键词 urban construction land suitability evaluation (UCLsE) multi-criteria evaluation based on GIs (MCE-G1s New Hefei
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Electronic Structures and Spectra of the Bases and Base Pairs of Nucleic Acids 被引量:1
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作者 WANG Zhi-zhong and BAI Ya-wen (Institute of Theoretical Chemistry, Jilin University, Changchun, 130023) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1992年第2期89-95,共7页
The present paper covers electronic structures and spectra of the bases and the base pairs of nucleic acids calculated by using the INDO/S method. For free bases we give the energy levels of ground states and transiti... The present paper covers electronic structures and spectra of the bases and the base pairs of nucleic acids calculated by using the INDO/S method. For free bases we give the energy levels of ground states and transition energies of low-lying excited states and discuss the band characters. The results indicate that the calculated spectra are in good agreement with experimental values. On the other hand, our calculations for A-T and G-C pairs are very beneficial to understanding hydrogen bond properties of these pairs. 展开更多
关键词 bases and base pairs of nucleic acid Electronic structures and spectra INDO/s
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Some Novel Schiff Bases from Pyruvic Acid with Amines Containing N &S Donor Atoms: Synthesis, Spectral Studies and X-Ray Crystal Structures 被引量:1
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作者 Abdul Azim Jambol Malai Haniti Sheikh Abdul Hamid +2 位作者 Aminul Huq Mirza Md. Shafiqul Islam Mohammad Rezaul Karim 《International Journal of Organic Chemistry》 2017年第1期42-56,共15页
Four Schiff bases, from pyruvic acid (1) with amines containing N and S donor atoms, thiocarbohydrazide (2, 61%), 2-methyl-3-thiosemicarbazide (3, 26%), S-benzyldithiocarbazate (4, 51%) and S-n-octyldithiocarbazate (5... Four Schiff bases, from pyruvic acid (1) with amines containing N and S donor atoms, thiocarbohydrazide (2, 61%), 2-methyl-3-thiosemicarbazide (3, 26%), S-benzyldithiocarbazate (4, 51%) and S-n-octyldithiocarbazate (5, 63%) have been successfully synthesized. The conventional method was used and a series of novel linear and cyclic Schiff bases were obtained with or without catalyst. All the Schiff bases were fully characterized by CHN elemental analysis, FT-IR, 1H & 13C NMR, EI-MS and two of the Schiff bases were further characterized by X-ray crystallographic structure analysis. Compound 2 crystallizes in the triclinic space group P-1 and unit cell dimensions are: a = 4.1777(8), b = 5.9538(11), c = 13.458(3) &ARING;, α = 92.759(6), β = 90.813(6), γ = 100.040(6)°, R1 = 0.0439. Compound 3 crystallizes in the orthorhombic space group P n a 2(1) and unit cell dimensions are: a = 5.5992(2), b = 11.3962(5), c = 10.6473(5), α = 92.759(6), β = 90.813(6), γ = 100.040(6)°, R1 = 0.0285. Compounds 2 and 3 were obtained as cyclic Schiff bases which are triazine derivatives. 展开更多
关键词 Pyruvic Acid schiff bases THIOCARBOHYDRAZIDE s-Alkyldithiocarbazates THIOsEMICARBAZIDE TRIAZINE N and s CONTAINING AMINEs
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Mathematical Model of Natural Gas Desulfurization Based on Membrane Absorption 被引量:1
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作者 Wang Shuli Ma Jun +1 位作者 Wang Ganyu Zhou Heng 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2014年第4期79-88,共10页
Models of mass transfer kinetics combined with mass transfer differential equation and mass transfer resistance equation were established on the basis of double-film theory. Mass transfer process of H2 S absorption by... Models of mass transfer kinetics combined with mass transfer differential equation and mass transfer resistance equation were established on the basis of double-film theory. Mass transfer process of H2 S absorption by means of polypropylene hydrophobic microporous hollow fiber membrane contactor was simulated using MDEA(N-methyldiethanolamine) as the absorption liquid and corresponding experiments of natural gas desulfurization were performed. The simulation results indicated that the removal rate of hydrogen sulfide showed positive dependence on the absorption liquid concentration and gas pressure. However, the desulfurization rate showed negative dependence on gas flow. The simulated values were in good agreement with the experimental results. The in-tube concentration of hydrogen sulfide at the same point increased with increase in the gas velocity. Axial concentration of hydrogen sulfide decreased rapidly at the beginning, and the decrease saw a slowdown during the latter half period. Hydrogen sulfide concentration dropped quickly in the radial direction, and the reduction in the radial direction was weakened with the increase of axial length due to the gradual reduction of hydrogen sulfide concentration along the tube. The desulfurization rate under given operating conditions can be predicted by this model, and the theoretical basis for membrane module design can also be provided. 展开更多
关键词 MEMBRANE based ABsORPTION H2s simulation MAss TRANsFER
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Synthesis and mesomorphic properties of fluorinated Schiff's base liquid crystals containing vinyl end groups 被引量:1
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作者 Qiang Wei Siquan Zhu +4 位作者 Lin Shi Lipei Zhang Xiaotao Yuan Hui Cao Huai Yang 《Journal of University of Science and Technology Beijing》 CSCD 2007年第4期373-377,共5页
Three kinds of fluorinated Schiff's base esters, 4-allyloxy-2-X-6-X-benzoic acid 4-[(2, 3, 4-trifluorophenylimino)methyl]phenyl ester, where X=H or F, were synthesized and characterized. Their chemical structures w... Three kinds of fluorinated Schiff's base esters, 4-allyloxy-2-X-6-X-benzoic acid 4-[(2, 3, 4-trifluorophenylimino)methyl]phenyl ester, where X=H or F, were synthesized and characterized. Their chemical structures were identified by Fourier transform infrared spectroscopy (FTIR) and ^1H nuclear magnetic resonance (^1H NMR). Their mesomorphic properties were studied by polarized optical microscopy (POM) and differential scanning calorimetry (DSC). It was found that all the three compounds exhibited enantiotropic nematic phases only. And their cleating point temperature and thermal range of mesophase decreased with the number of fluorine atoms on the rigid core of the compounds; while their melting point temperature showed no distinct regularity. 展开更多
关键词 sYNTHEsIs schiff's base fluorinated liquid crystal vinyl end group
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Alzheimer’s Disease Diagnosis Based on a Semantic Rule-Based Modeling and Reasoning Approach 被引量:1
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作者 Nora Shoaip Amira Rezk +3 位作者 Shaker EL-Sappagh Tamer Abuhmed Sherif Barakat Mohammed Elmogy 《Computers, Materials & Continua》 SCIE EI 2021年第12期3531-3548,共18页
Alzheimer’s disease(AD)is a very complex disease that causes brain failure,then eventually,dementia ensues.It is a global health problem.99%of clinical trials have failed to limit the progression of this disease.The ... Alzheimer’s disease(AD)is a very complex disease that causes brain failure,then eventually,dementia ensues.It is a global health problem.99%of clinical trials have failed to limit the progression of this disease.The risks and barriers to detecting AD are huge as pathological events begin decades before appearing clinical symptoms.Therapies for AD are likely to be more helpful if the diagnosis is determined early before the final stage of neurological dysfunction.In this regard,the need becomes more urgent for biomarker-based detection.A key issue in understanding AD is the need to solve complex and high-dimensional datasets and heterogeneous biomarkers,such as genetics,magnetic resonance imaging(MRI),cerebrospinal fluid(CSF),and cognitive scores.Establishing an interpretable reasoning system and performing interoperability that achieves in terms of a semantic model is potentially very useful.Thus,our aim in this work is to propose an interpretable approach to detect AD based on Alzheimer’s disease diagnosis ontology(ADDO)and the expression of semantic web rule language(SWRL).This work implements an ontology-based application that exploits three different machine learning models.These models are random forest(RF),JRip,and J48,which have been used along with the voting ensemble.ADNI dataset was used for this study.The proposed classifier’s result with the voting ensemble achieves a higher accuracy of 94.1%and precision of 94.3%.Our approach provides effective inference rules.Besides,it contributes to a real,accurate,and interpretable classifier model based on various AD biomarkers for inferring whether the subject is a normal cognitive(NC),significant memory concern(SMC),early mild cognitive impairment(EMCI),late mild cognitive impairment(LMCI),or AD. 展开更多
关键词 Mild cognitive impairment Alzheimer’s disease knowledge based semantic web rule language reasoning system ADNI dataset machine learning techniques
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Individualized music for dementia:Evolution and application of evidence-based protocol 被引量:3
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作者 Linda A Gerdner 《World Journal of Psychiatry》 SCIE 2012年第2期26-32,共7页
The theory-based intervention of individualized music has been evaluated clinically and empirically leading to advancement and refinement of an evidence-based protocol, currently in its 5th edition. An expanded versio... The theory-based intervention of individualized music has been evaluated clinically and empirically leading to advancement and refinement of an evidence-based protocol, currently in its 5th edition. An expanded version of the protocol was written for professional health care providers with a consumer version tailored for family caregivers. The underlying mid-range theory is presented along with a seminal study that was followed by further research in the United States, Canada, Great Britain, France, Sweden, Norway, Japan and Taiwan. Key studies are summarized. Given its efficacy when implemented by research staff, studies have advanced to testing the intervention under real-life conditions when implemented and evaluated by trained nursing assistants in long-term care facilities and visiting family members. In addition, one study evaluated the implementation of music by family members in the home setting. Initial research focused on agitation as the dependent variable with subsequent research indicating a more holistic response such as positive affect, expressed satisfaction, and meaningful interaction with others. The article advances by describing on-line programs designed to train health care professionals in the assessment, implementation and evaluation of individualized music. In addition, Gerdner has written a story for apicture book intended for children and their families(in press). The story models principles of individualized music to elicit positive memories, reduce anxiety and agitation, and promote communication. The article concludes with implications for future research. 展开更多
关键词 Individualized MUsIC DEMENTIA Alzheimer’s disease AGITATION EVIDENCE-baseD PROTOCOL
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Characterizing some gossypol and gossypolone Schiff's bases by studying their fragmentation patterns with electrospray ionization tandem mass spectra
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作者 Long Zhang Xing Xin Cao +2 位作者 Hai Xia Jiang Biao Jiang Yu Xin Cui 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第6期716-719,共4页
To investigate the structural form of gossypol and gossypolone Schiff's bases, seven relevant Schiff's bases were synthesized and the electrospray ionization-tandem mass spectrometry (ESI-MS/MS) with low-energy co... To investigate the structural form of gossypol and gossypolone Schiff's bases, seven relevant Schiff's bases were synthesized and the electrospray ionization-tandem mass spectrometry (ESI-MS/MS) with low-energy collision-induced dissociation was used to analyze their fragmentations. A common fragmentation pathway with the loss of RNH2 from those schiff's bases quasi-molecular ions was observed and proposed on the basis of their MS/MS spectra data. This common pathway indicated that those Schiff's bases existed mainly as the enamine form not the imine form previously showed in most reports. 展开更多
关键词 Gossypol schiff's bases Gossypolone schiff's bases EsI-Ms Enamine form Imine form
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