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基于SERVQUAL5+2模型的供电服务品质评价 被引量:2
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作者 谢传胜 范艳霞 《华北电力大学学报(社会科学版)》 2008年第2期14-18,共5页
结合供电服务品质特性,对服务质量模型加以改进,增加安全性和稳定性两个质量属性,形成SERVQUAL5+2专项评价模型,并据该改进模型构建供电服务品质外部评价指标体系,基于因子分析法和群组决策法进行算例分析,国内几家大型供电公司的试用... 结合供电服务品质特性,对服务质量模型加以改进,增加安全性和稳定性两个质量属性,形成SERVQUAL5+2专项评价模型,并据该改进模型构建供电服务品质外部评价指标体系,基于因子分析法和群组决策法进行算例分析,国内几家大型供电公司的试用结果表明该评价体系的有效性。 展开更多
关键词 servqual5+2模型 供电服务品质 评价指标
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Crystallization thermodynamics of 2,4(5)-dinitroimidazole in binary solvents 被引量:2
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作者 Pengbao Lian Lizhen Chen +3 位作者 Dan He Guangyuan Zhang Zishuai Xu Jianlong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第5期173-182,共10页
2,4(5)-Dinitroimidazole(2,4(5)-DNI)is an important organic intermediate,and itself can also be used for energetic material.In this work,the solubility of 2,4(5)-DNI in(methanol+water,acetonitrile+water,acetone+water)b... 2,4(5)-Dinitroimidazole(2,4(5)-DNI)is an important organic intermediate,and itself can also be used for energetic material.In this work,the solubility of 2,4(5)-DNI in(methanol+water,acetonitrile+water,acetone+water)binary solvents were measured by using a dynamic test method from 278.15 K to 323.15 K under 101.1 k Pa.The Jouyban–Acree model,van't Hoff–Jouyban–Acree model,Apelblat–Jouyb an–Acree model,Ma model,and Sun model were used to correlate the experimental data.The values of relative average deviation(RAD)and root-mean-square deviation(RMSD)were very small,indicating that the error between the experimental value and the correlated value was very small.The thermodynamic parameters such as dissolution enthalpy,dissolution entropy and Gibbs energy were calculated based on solubility data.High-purity of 2,4(5)-DNI was efficiently obtained by using cooling and dilution crystallization method. 展开更多
关键词 2 4(5)-Dinitroimidazole Solid-liquid equilibrium Solubility model Three thermodynamic parameters Cooling and dilution crystallization
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Role of neutrophil chemoattractant CXCL5 in SARS-CoV-2 infection-induced lung inflammatory innate immune response in an in vivo hACE2 transfection mouse model 被引量:3
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作者 Yan Liang Heng Li +7 位作者 Jing Li Ze-Ning Yang Jia-Li Li Hui-Wen Zheng Yan-Li Chen Hai-Jing Shi Lei Guo Long-Ding Liu 《Zoological Research》 SCIE CAS CSCD 2020年第6期621-631,共11页
Understanding the pathogenesis of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and clarifying antiviral immunity in hosts are critical aspects for the development of vaccines and antivirals.Mice are freq... Understanding the pathogenesis of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and clarifying antiviral immunity in hosts are critical aspects for the development of vaccines and antivirals.Mice are frequently used to generate animal models of infectious diseases due to their convenience and ability to undergo genetic manipulation.However,normal adult mice are not susceptible to SARS-CoV-2.Here,we developed a viral receptor(human angiotensin-converting enzyme 2,hACE2)pulmonary transfection mouse model to establish SARS-CoV-2 infection rapidly in the mouse lung.Based on the model,the virus successfully infected the mouse lung 2 days after transfection.Viral RNA/protein,innate immune cell infiltration,inflammatory cytokine expression,and pathological changes in the infected lungs were observed after infection.Further studies indicated that neutrophils were the first and most abundant leukocytes to infiltrate the infected lungs after viral infection.In addition,using infected CXCL5-knockout mice,chemokine CXCL5 was responsible for neutrophil recruitment.CXCL5 knockout decreased lung inflammation without diminishing viral clearance,suggesting a potential target for controlling pneumonia. 展开更多
关键词 SARS-CoV-2 Mouse model Lung infection ACE2 NEUTROPHIL CXCL5
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Nonequilibrium behavior of the kinetic metamagnetic spin-5/2 Blume–Capel model
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作者 müt Temizer 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期350-359,共10页
The dynamic magnetic behavior of the kinetic metamagnetic spin-5/2 Blume-Capel model is examined, within a mean-field approach, under a time-dependent oscillating magnetic field. To describe the kinetics of the system... The dynamic magnetic behavior of the kinetic metamagnetic spin-5/2 Blume-Capel model is examined, within a mean-field approach, under a time-dependent oscillating magnetic field. To describe the kinetics of the system, Glauber- type stochastic dynamics has been utilized. The mean-field dynamic equations of the model are obtained from the Master equation. Firstly, these dynamic equations are solved to find the phases in the system. Then, the dynamic phase transition temperatures are obtained by investigating the thermal behavior of dynamic sublattice magnetizations. Moreover, from this investigation, the nature of the phase transitions (first- or second-order) is characterized. Finally, the dynamic phase diagrams are plotted in five different planes. It is found that the dynamic phase diagrams contain the paramagnetic (P), antiferromagnetic (AF5/2, AF3/2, AF1/2) phases and five different mixed phases. The phase diagrams also display many dynamic critical points, such as tricritical point, triple point, quadruple point, double critical end point and separating point. 展开更多
关键词 METAMAGNETISM spin-5/2 Blume-Capel model dynamic phase transitions dynamic phase dia-grams Glauber-type stochastic dynamics
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The synergistic effects of PRDX5 and Nrf2 on lung cancer progression and drug resistance under oxidative stress in the zebrafish models
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作者 SITONG QIAN YING FANG +11 位作者 CHENGYUN YAO YONGSHENG WANG ZHI ZHANG XIAOHUA WANG JIN GAO YONG FENG LEI SUN RUNYUE ZOU GUOREN ZHOU JINJUN YE RUIXUE XIA HONGPING XIA 《Oncology Research》 SCIE 2022年第2期53-64,共12页
Previous studies have shown that PRDX5 and Nrf2 are antioxidant proteins related to abnormal reactive oxidative species(ROS).PRDX5 and Nrf2 play a critical role in the progression of inflammations and tumors.The combin... Previous studies have shown that PRDX5 and Nrf2 are antioxidant proteins related to abnormal reactive oxidative species(ROS).PRDX5 and Nrf2 play a critical role in the progression of inflammations and tumors.The combination of PRDX5 and Nrf2 was examined by Co-immunoprecipitation,western blotting and Immunohistochemistry.H2O2 was applied to affect the production of ROS and induced multi-resistant protein 1(MRP1)expression in NSCLC cells.The zebrafish models mainly investigated the synergistic effects of PRDX5 and Nrf2 on lung cancer drug resistance under oxidative stress.We showed that PRDX5 and Nrf2 form a complex and significantly increase the NSCLC tissues compared to adjacent tissues.The oxidative stress improved the combination of PRDX5 and Nrf2.We demonstrated that the synergy between PRDX5 and Nrf2 is positively related to the proliferation and drug resistance of NSCLC cells in the zebrafish models.In conclusion,our data indicated that PRDX5 could bind to Nrf2 and has a synergistic effect with Nrf2.Meanwhile,in the zebrafish models,PRDX5 and Nrf2 have significant regulatory impacts on lung cancer progression and drug resistance activities under oxidative stress. 展开更多
关键词 PRDX5 NRF2 Oxidative stress Lung cancer Drug resistance Zebrafish models
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Intelligent In-Vehicle Safety System Based on Yolov5
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作者 Biyun Chen Wei Cai Jinwen Zhu 《Journal of Computer and Communications》 2024年第3期207-218,共12页
In order to reduce the occurrence of traffic accidents and assist drivers to avoid dangerous driving. This paper presents a smart in-vehicle safety system that utilises the Yolov5 algorithm. Yolov5 algorithm is used t... In order to reduce the occurrence of traffic accidents and assist drivers to avoid dangerous driving. This paper presents a smart in-vehicle safety system that utilises the Yolov5 algorithm. Yolov5 algorithm is used to anticipate driver fatigue and distraction behaviours, and remind drivers to pay attention to safe driving in time. The system continuously splits the frames and analyses the frame content through the video feedback from the front camera, compared to the traditional machine learning, Yolov5’s mosaic data is enhanced, resulting in a batch size enhancement of 92.3%, and it also uses the Drop Block mechanism to prevent overfitting. The hardware of this system uses STM32 microcontroller and uses system DMA interrupt control and buzzer alarm device to warn about dangerous driving behaviour. 展开更多
关键词 Behaviour Detection STM32 Pyside2 Yolov5 Dlib Open Source Library Perclos model
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5-杂氮-2′-脱氧胞苷对人鼻咽癌裸鼠移植瘤的抑制作用 被引量:15
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作者 张松 孔维佳 +2 位作者 王彦君 韩月臣 张丹 《癌症》 SCIE CAS CSCD 北大核心 2005年第10期1201-1205,共5页
背景与目的:5-杂氮-2′-脱氧胞苷是DNA甲基转移酶抑制剂,能使因甲基化而失活的抑癌基因重新激活,进而抑制肿瘤的生长。本文观察了5-杂氮-2′-脱氧胞苷对人鼻咽癌细胞及其裸鼠移植瘤的抑制作用,探讨其抗肿瘤效应及可能的机理,寻找鼻咽癌... 背景与目的:5-杂氮-2′-脱氧胞苷是DNA甲基转移酶抑制剂,能使因甲基化而失活的抑癌基因重新激活,进而抑制肿瘤的生长。本文观察了5-杂氮-2′-脱氧胞苷对人鼻咽癌细胞及其裸鼠移植瘤的抑制作用,探讨其抗肿瘤效应及可能的机理,寻找鼻咽癌治疗的新靶点。方法:用5-杂氮-2′-脱氧胞苷处理人鼻咽癌细胞,观察其对细胞生长的抑制及死亡相关蛋白激酶基因(death-associated proteinkinase,DAPK)甲基化情况。建立人鼻咽癌移植瘤裸鼠模型,用5-杂氮-2′-脱氧胞苷处理裸鼠,观察移植瘤的生长情况,并用RT-PCR和免疫组织化学技术检测DAPK基因mRNA及蛋白表达的变化。结果:未经5-杂氮-2′-脱氧胞苷处理的CNE细胞中DAPKmRNA不表达。经5-杂氮-2′-脱氧胞苷处理后,不同药物浓度组的细胞中均有DAPKmRNA表达,且表达随浓度增高而增强。5-杂氮-2′-脱氧胞苷对人鼻咽癌细胞及其裸鼠移植瘤的生长均有明显的抑制作用,且能使失活的DAPK基因重新激活。药物作用4周后,用药组裸鼠体重(22.35±2.02)g与对照组(21.68±2.14)g之间无显著性差异(t=0.011,P>0.05),用药组肿瘤的体积(195.32±27.57)mm3较对照组(343.67±23.08)mm3明显减小,两者之间有显著性差异(t=10.11,P﹤0.01)。在鼻咽癌移植瘤中,对照组DAPK均不表达,而用药组出现表达。结论:5-杂氮-2′-脱氧胞苷对人鼻咽癌细胞及其裸鼠移植瘤的抑制作用可能是因为其使因甲基化而失活的抑癌基因DAPK再转录,诱导该基因的表达,从而抑制肿瘤细胞的生长和增殖。 展开更多
关键词 鼻咽肿瘤 移植瘤 裸鼠模型 5-杂氮-2’-脱氧胞苷 死亡相关蛋白激酶
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5-硝基-1H-吲哚-2-羧酸与牛血红蛋白相互作用的分子模拟与光谱研究 被引量:4
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作者 毛慧 蔡炳锋 +2 位作者 赵波 李利 沈健 《化学研究与应用》 CAS CSCD 北大核心 2009年第5期675-679,共5页
运用密度泛函理论B3LYP/6-31G*方法对5-硝基-1H-吲哚-2-羧酸(NIA)的几何构型进行了全优化。在这基础上,用分子对接技术确定了NIA与牛血红蛋白(BHb)之间的作用位点、作用力类型及相互作用能。理论计算的结果表明NIA和BHb相互作用的静电能... 运用密度泛函理论B3LYP/6-31G*方法对5-硝基-1H-吲哚-2-羧酸(NIA)的几何构型进行了全优化。在这基础上,用分子对接技术确定了NIA与牛血红蛋白(BHb)之间的作用位点、作用力类型及相互作用能。理论计算的结果表明NIA和BHb相互作用的静电能是-208.9 kcal.mol-1,范德华能为-180.5 kcal.mol-1,势能为-389.4 kcal.mol-1。NIA与BHb中A链上的Leu129、Ser133残基形成氢键,而NIA分子中的骨架苯环部分易与疏水氨基酸,包括产生荧光的Tyr残基等发生作用,这与NIA能使BHb荧光淬灭的实验结果是一致的。 展开更多
关键词 5-硝基-1H-吲哚-2-羧酸 牛血红蛋白 相互作用 分子模拟
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5-杂氮-2'-脱氧胞苷抑制人喉癌裸鼠移植瘤的机制探讨 被引量:3
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作者 张松 孔维佳 +2 位作者 郭长凯 王彦君 韩月臣 《中国肿瘤临床》 CAS CSCD 北大核心 2005年第21期1212-1215,共4页
目的:探讨5-杂氮-2′-脱氧胞苷对Hep-2人喉癌裸鼠移植瘤生长的影响,寻找喉癌治疗的新靶点。方法:建立喉癌裸鼠移植瘤模型,用5-杂氮-2′-脱氧胞苷处理裸鼠,观察移植瘤的生长情况并绘制其生长曲线。用RT-PCR和免疫组织化学技术检测死亡相... 目的:探讨5-杂氮-2′-脱氧胞苷对Hep-2人喉癌裸鼠移植瘤生长的影响,寻找喉癌治疗的新靶点。方法:建立喉癌裸鼠移植瘤模型,用5-杂氮-2′-脱氧胞苷处理裸鼠,观察移植瘤的生长情况并绘制其生长曲线。用RT-PCR和免疫组织化学技术检测死亡相关蛋白激酶(Death-associatedproteinkinaseDAPK)基因mRNA及蛋白表达的变化。结果:5-杂氮-2′-脱氧胞苷对人喉癌裸鼠移植瘤处理后用药组和对照组之间裸鼠的体重无明显差异(t=0.011,P>0.05),而移植瘤的体积用药组较对照组明显减小,统计学差异有显著性(t=10.11,P<0.01)。在喉癌移植瘤组织中,对照组DAPK均不表达,而用药组出现表达。结论:5-杂氮-2′-脱氧胞苷在体内能使因甲基化而失活的抑癌基因再转录,诱导其表达,进而抑制喉癌移植瘤的生长。 展开更多
关键词 HEP-2细胞系 5-杂氮-2′-脱氧胞苷 裸鼠模型 死亡相关蛋白激酶
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“5+2”:培养本科学历小学教师的有效模式 被引量:24
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作者 黄正平 《教师教育研究》 CSSCI 北大核心 2008年第1期27-31,共5页
培养高学历小学教师是社会经济和教育发展的必然要求。选择招收初中毕业生的"5+2"培养模式与高中起点四年制培养模式相比具有明显的优势,可以把中师丰富的小学教师培养经验和高师具有师资、设备优势及高校的学术气氛有机结合... 培养高学历小学教师是社会经济和教育发展的必然要求。选择招收初中毕业生的"5+2"培养模式与高中起点四年制培养模式相比具有明显的优势,可以把中师丰富的小学教师培养经验和高师具有师资、设备优势及高校的学术气氛有机结合起来。实施"5+2"培养本科学历小学教师模式,必须切实加强课程教材建设、学科专业建设、职业能力建设和师资队伍建设。 展开更多
关键词 5+2”模式 本科学历 小学教师 培养策略
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2.5维问题电阻率正演的新方法 被引量:4
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作者 毛先进 鲍光淑 《中南工业大学学报》 CSCD 北大核心 1997年第4期307-310,共4页
利用格林函数导出了2.5维问题,以研究区域网格化中任意电性分布条件下空间电位所满足的边界积分方程.用边界元法解该方程求得地表和地下的电位分布,从而进行视电阻率模拟.运用该方法得出的计算结果与前人所作的数值模拟和实验结果... 利用格林函数导出了2.5维问题,以研究区域网格化中任意电性分布条件下空间电位所满足的边界积分方程.用边界元法解该方程求得地表和地下的电位分布,从而进行视电阻率模拟.运用该方法得出的计算结果与前人所作的数值模拟和实验结果进行对比表明,作者提出的方法克服了有限元法和α-中心法的许多缺陷,将其用于电阻率成像可大大提高成像质量,扩大电阻率成像技术的实用范围. 展开更多
关键词 电阻率 正演法 任意电性分布 电法勘探
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基于几何结构的2.5D卡通建模 被引量:1
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作者 刘艳 胡艳宏 孙战利 《计算机工程》 CAS CSCD 北大核心 2015年第5期243-248,253,共7页
二维卡通制作技术大致分为计算机辅助2D卡通动画制作和利用3D建模技术渲染生成动画。将两者结合,提出一种2.5D卡通制作模型,通过几何结构的旋转进行纹理贴图,并构造卡通的旋转过程。在2D动画中,一个卡通形象本身隐含几何结构,将卡通形... 二维卡通制作技术大致分为计算机辅助2D卡通动画制作和利用3D建模技术渲染生成动画。将两者结合,提出一种2.5D卡通制作模型,通过几何结构的旋转进行纹理贴图,并构造卡通的旋转过程。在2D动画中,一个卡通形象本身隐含几何结构,将卡通形象定义为由只含一个典型几何结构卡通元素构成的卡通对象,利用典型几何结构二维投影变化规律,构建相应结构卡通元素的变形算法,分析长方体和球体卡通元素在转动时投影的变化规律,给出基于这些规律实现相应结构卡通元素伪3D转动效果的算法。通过长方体、球体、圆柱体进行旋转的实验结果证明了算法的有效性。 展开更多
关键词 2.5D建模 投影轮廓线 纹理贴图 投影 卡通元素 卡通对象
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APP5肽类似物P165对2型糖尿病大鼠学习记忆的影响
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作者 邵志敏 张炙萍 +5 位作者 赵志炜 庄晓明 姬志娟 张景燕 盛树力 王蓉 《首都医科大学学报》 CAS 2008年第2期162-166,共5页
目的研究APP5肽类似物P165(简称P165)对2型糖尿病大鼠学习记忆的影响。方法将Sprague Dawley(SD)大鼠分为正常组(C)、糖尿病组(DM)、DM+P165小剂量组、DM+P165大剂量组。采用高脂高糖饮食及腹腔注射小剂量链脲菌素(streptozotocin,STZ)... 目的研究APP5肽类似物P165(简称P165)对2型糖尿病大鼠学习记忆的影响。方法将Sprague Dawley(SD)大鼠分为正常组(C)、糖尿病组(DM)、DM+P165小剂量组、DM+P165大剂量组。采用高脂高糖饮食及腹腔注射小剂量链脲菌素(streptozotocin,STZ)的方法,建立2型糖尿病模型。成模后给予SD大鼠P165灌胃治疗8周后行水迷宫实验。每周检测动物的空腹血糖和体质量。结果与C组相比,DM组从第2天开始逃避潜伏期明显延长(P<0.01);与DM组比较,P165治疗组逃避潜伏期明显缩短(P<0.05)。空间探索实验结果显示,与C组比较,DM组第1次穿越平台所在位置时间显著延长(P<0.05),在平台所在象限游泳距离显著缩短(P<0.01);与DM组相比,P165治疗组第1次穿越平台所在位置时间明显缩短(P<0.01和P<0.05),DM+P165小剂量组在平台所在象限游泳距离显著延长(P<0.01)。从给予P165治疗开始到实验结束,DM组、DM+P165小剂量组和DM+P165大剂量组动物血糖差异均无统计学意义。结论2型糖尿病大鼠存在学习记忆功能障碍,P165能够缩短动物水迷宫实验逃避潜伏期和找到平台时间,改善模型动物的学习记忆功能,但并不影响血糖。 展开更多
关键词 APP5肽类似物P165 2型糖尿病 水迷宫 学习记忆 模型 大鼠
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3,5,6-三氯-2-吡啶醇在紫色土中的吸附特征与参数估计
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作者 雷文娟 霍喜 周向阳 《农业机械学报》 EI CAS CSCD 北大核心 2017年第5期267-274,共8页
通过批量平衡实验和土柱实验获得了3,5,6-三氯-2-吡啶醇(简称TCP)在紫色土土壤中的吸附特征,并应用模型对上述吸附过程进行模拟。其中,吸附动力学参数通过准一阶、准二阶动力学方程、Elovich模型和粒子扩散模型反演;等温吸附参数应用Fre... 通过批量平衡实验和土柱实验获得了3,5,6-三氯-2-吡啶醇(简称TCP)在紫色土土壤中的吸附特征,并应用模型对上述吸附过程进行模拟。其中,吸附动力学参数通过准一阶、准二阶动力学方程、Elovich模型和粒子扩散模型反演;等温吸附参数应用Freundlic、Langmuir和Linear模型反演;土柱实验中的吸附参数基于Thomas与YoonNelson模型反演。结果表明:TCP在紫色土中的吸附动力学过程包含快速的表面物理吸附和慢速的内部化学扩散2个阶段,且粒子扩散模型表现最好。等温吸附过程可以通过Freundlic模型描述(R^2=0.94),获得的吸附容量常数K_f为0.79 mL/g,吸附水平较小说明TCP在紫色土中具有较大的迁移风险。TCP在土柱中达到平衡需要的时间约为1 215 min,土壤对TCP的吸附率为10.65%。Thomas与Yoon-Nelson模型能够较好地模拟TCP在紫色土中的动态吸附曲线(R^2≥0.84),获得的平衡浓度q0为0.008 6 mg/g。 展开更多
关键词 3 5 6-三氯-2-吡啶醇 紫色土 吸附实验 吸附模型
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V_2O_5/TiO_2片状催化剂上NH_3选择性还原NO_x反应传质情况研究
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作者 曲虹霞 钟秦 《北京化工大学学报(自然科学版)》 CAS CSCD 2004年第4期12-15,共4页
在固定床反应器中对片状V2 O5/TiO2 催化剂上NH3 选择性催化还原NOx 的反应体系进行了传质对反应影响的研究。V2 O5/TiO2 催化剂上NH3 选择性催化还原NOx 的反应为 1级反应 ,内扩散对反应速率和NOx 转化率的影响显著。NOx 转化率可以表... 在固定床反应器中对片状V2 O5/TiO2 催化剂上NH3 选择性催化还原NOx 的反应体系进行了传质对反应影响的研究。V2 O5/TiO2 催化剂上NH3 选择性催化还原NOx 的反应为 1级反应 ,内扩散对反应速率和NOx 转化率的影响显著。NOx 转化率可以表示为空速和其它参数的显函数并获得单一的解析解。实验与模型结果相一致 ,模型能够较好的反映转化率的变化趋势 。 展开更多
关键词 脱氮 V2O5/TiO2片状催化剂 选择性催化还原 传质模型
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紫外-可见分光光度法在定量监测2,3,5-三碘苯甲酸缓释中的应用 被引量:2
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作者 刘来俊 徐海燕 +2 位作者 赵帆 王富军 王璐 《纺织学报》 EI CAS CSCD 北大核心 2019年第2期20-25,共6页
为研究显影剂2,3,5-三碘苯甲酸(TIBA)在显影纤维聚对二氧环己酮(PPDO)降解液中的缓释规律,采用紫外可见分光光度法探究了TIBA在不同体积比的磷酸盐缓冲溶液(PBS)和乙醇共混降解液(V_(PBS)∶V_(乙醇)分别为1∶3、1∶1和3∶1)中的紫外-可... 为研究显影剂2,3,5-三碘苯甲酸(TIBA)在显影纤维聚对二氧环己酮(PPDO)降解液中的缓释规律,采用紫外可见分光光度法探究了TIBA在不同体积比的磷酸盐缓冲溶液(PBS)和乙醇共混降解液(V_(PBS)∶V_(乙醇)分别为1∶3、1∶1和3∶1)中的紫外-可见分光光谱和回归曲线,根据回归曲线,测定降解液的吸光度值及计算PPDO纤维在降解过程中显影剂TIBA的释放量,借助药物缓释理论模型进行拟合,并分析相应的释放规律。结果表明:在3种共混溶液中,均能得到回归关系明显的线性方程,考虑到乙醇用量,选择PBS与乙醇的体积比为3∶1的溶液作为标准液,并且溶液在37℃的环境中静置8 d后仍能保持一定的稳定性;模型拟合结果表明TIBA的释放规律符合一级释放的函数模型。 展开更多
关键词 紫外-可见分光光度法 显影纤维 纤维降解 2 3 5-三碘苯甲酸 释放模型
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Cytochrome b5 reductase 2 suppresses tumor formation in nasopharyngeal carcinoma by attenuating angiogenesis 被引量:3
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作者 Huixin Ming Ying Lan +5 位作者 Feng He Xue Xiao Xiaoying Zhou Zhe Zhang Ping Li Guangwu Huang 《Chinese Journal of Cancer》 SCIE CAS CSCD 2015年第10期459-467,共9页
Background:Cytochrome b5 reductase 2(CYB5R2) is a potential tumor suppressor that inhibits cell proliferation and motility in nasopharyngeal carcinoma(NPC).Inactivation of CYB5R2 is associated with lymph node metastas... Background:Cytochrome b5 reductase 2(CYB5R2) is a potential tumor suppressor that inhibits cell proliferation and motility in nasopharyngeal carcinoma(NPC).Inactivation of CYB5R2 is associated with lymph node metastasis in NPC.This study aimed to explore the mechanisms contributing to the anti-neoplastic effects of CYB5R2.Methods:Polymerase chain reaction(PCR) assays were used to analyze the transcription of 84 genes known to be involved in representative cancer pathways in the NPC cell line HONE1.NPC cell lines CNE2 and HONE1 were transiently transfected with CYB5R2,and data was validated by real-time PCR.A chick chorioallantoic membrane(CAM)embryo model was implanted with CYB5R2-expressing CNE2 and HONE1 cells to evaluate the effect of CYB5R2 on angiogenesis.An immunohistochemical assay of the CAM model was used to analyze the protein expression of vascular endothelial growth factor(VEGF).Results:In CYB5R2-transfected NPC cells,PCR assays revealed up-regulated mRNA levels of Fas cell surface death receptor(FAS),FBJ murine osteosarcoma viral oncogene homolog(FOS),phosphoinositide-3-kinase regulatory subunit 1(PIK3R1),integrin beta 3(ITGB3),metastasis suppressor 1(MTSSl),interferon beta 1(IFNB1),and cyclin-dependent kinase inhibitor 2A(CDKN2A) and down-regulated levels of integrin beta 5(ITGB5),insulin-like growth factor 1(IGF1),TEK tyrosine kinase(TEK),transforming growth factor beta receptor 1(TGFBRl),and VEGF.The angiogenesis in the CAM model implanted with CYB5R2-transfected NPC cells was inhibited.Down-regulation of VEGF by CYB5R2 in NPC cells was confirmed by immunohistochemical staining in the CAM model.Conclusion:CYB5R2 up-regulates the expression of genes that negatively modulate angiogenesis in NPC cells and down-regulates the expression of VEGF to reduce angiogenesis,thereby suppressing tumor formation. 展开更多
关键词 CYTOCHROME b5 REDUCTASE 2 NASOPHARYNGEAL carcinoma CHICK embryo model ANGIOGENESIS
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辽东湾坳陷新近系特稠油成藏模式与成藏过程——以旅大5-2北油田为例 被引量:22
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作者 徐长贵 王冰洁 +2 位作者 王飞龙 宛良伟 张如才 《石油学报》 EI CAS CSCD 北大核心 2016年第5期599-609,共11页
辽东湾坳陷断裂构造带原油稠化作用强烈,形成了复杂的特稠油油藏,其特殊的油藏模式为勘探阶段的油藏评价带来巨大风险。基于测井资料、岩心和薄片观察结果、原油地化分析和包裹体测温等技术,建立了旅大5-2北油田特稠油油藏模式,并对其... 辽东湾坳陷断裂构造带原油稠化作用强烈,形成了复杂的特稠油油藏,其特殊的油藏模式为勘探阶段的油藏评价带来巨大风险。基于测井资料、岩心和薄片观察结果、原油地化分析和包裹体测温等技术,建立了旅大5-2北油田特稠油油藏模式,并对其成藏过程进行研究。结果表明:明化镇组和馆陶组特稠油藏与常规油藏相比具有不统一的油-水界面、弧形的油藏边界、油-水关系倒置以及油顶为分选极差的砂砾岩等特征;在距今约25 Ma东营组沉积末期,来自辽中凹陷和辽西南洼的原油在东营组经历了第一期成藏,由于处于断裂带且埋深较浅,原油遭初步的生物降解作用;自明化镇组沉积期距今5 Ma以来,东营组聚集原油遭受破坏,沿控圈断层作垂向运移至浅层,受早期稠化作用的影响,一方面在很大程度上降低了对保存条件的要求,原油可以在盖层条件较差的储层中聚集成藏,另一方面原油优先选择物性较好的储层进行充注,伴随着聚集后进一步强烈的生物降解作用,形成特殊的油藏模式。 展开更多
关键词 特稠油 油藏模式 成藏机理 旅大5-2北油田 辽东湾坳陷
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Application of Water Quality Model QUAL2K to Model the Dispersion of Pollutants in River Ndarugu, Kenya 被引量:4
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作者 Letensie Tseggai Hadgu Maurice Omondi Nyadawa +2 位作者 John Kimani Mwangi Purity Muthoni Kibetu Beraki Bahre Mehari 《Computational Water, Energy, and Environmental Engineering》 2014年第4期162-169,共8页
Ndarugu River, Kenya, during its course through the different agricultural and industrial areas of Gatundu, Gachororo and Juja farms, receives untreated industrial, domestic and agricultural waste of point source disc... Ndarugu River, Kenya, during its course through the different agricultural and industrial areas of Gatundu, Gachororo and Juja farms, receives untreated industrial, domestic and agricultural waste of point source discharges from coffee and tea factories. During wet season the water is also polluted by non-point (diffuse) sources created by runoff carrying soil, fertilizer and pesticide residues from the catchment area. This study involved the calibration of water quality model QUAL2K to predict the water quality of this segment of the river. The model was calibrated and validated for flow discharge (Q), temperature (T&deg), flow velocity (V), biochemical oxygen demand (BOD5), dissolved oxygen (DO) and nitrate (NO3-N), using data collected and analyzed during field and laboratory measurements done in July and November-December 2013. The model was then used in simulation and its performance was evaluated using statistical criteria based on correlation coefficient (R2) and standard errors (SE) between the observed and simulated data. The model reflected the field data quite well with minor exceptions. In spite of these minor differences between the measured and simulated data set at some points, the calibration and validation results are acceptable especially for developing countries where the financial resources for frequent monitoring works and higher accuracy data analysis are very limited. The water is being polluted by the human activities in the catchment. There is need for proper control of wastewater by various techniques, and preliminary treatment of waste discharges prior to effluent disposal. Management of the watershed is necessary so as to protect the river from the adverse impacts of agricultural activities and save it from further deterioration. 展开更多
关键词 BOD5 DO QUAL2K RIVER POLLUTION Water Quality modeling
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Hot deformation behaviors and dynamic recrystallization mechanism of Ti-35421 alloy inβsingle field 被引量:1
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作者 Tong LU Zhen-hua DAN +3 位作者 Kai LI Dan-qing YI Lian ZHOU Hui CHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第9期2889-2907,共19页
Hot deformation behaviors and microstructure evolution of Ti-3Al-5Mo-4Cr-2Zr-1Fe(Ti-35421)alloy in theβsingle field are investigated by isothermal compression tests on a Gleeble-3500 simulator at temperatures of 820-... Hot deformation behaviors and microstructure evolution of Ti-3Al-5Mo-4Cr-2Zr-1Fe(Ti-35421)alloy in theβsingle field are investigated by isothermal compression tests on a Gleeble-3500 simulator at temperatures of 820-900°C and strain rates of 0.001-1 s^(-1).The research results show that discontinuous yield phenomenon and rheological softening are affected by the strain rates and deformation temperatures.The critical conditions for dynamic recrystallization and kinetic model of Ti-35421 alloy are determined,and the Arrhenius constitutive model is constructed.The rheological behaviors of Ti-35421 alloys aboveβphase transformation temperature are predicted by the constitutive model accurately.The EBSD analysis proves that the deformation softening is controlled by dynamic recovery and dynamic recrystallization.In addition,continuous dynamic recrystallization is determined during hot deformation,and the calculation model for recrystallization grain sizes is established.Good linear dependency between the experimental and simulated values of recrystallized grain sizes indicates that the present model can be used for the prediction of recrystallized grain size with high accuracy. 展开更多
关键词 Ti-3Al-5Mo-4Cr-2Zr-1Fe alloy microstructure evolution Arrhenius constitutive model deformation softening continuous dynamic recrystallization
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