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进水分配比对分段进水PN/A工艺脱氮性能影响
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作者 李冬 王凯璐 +2 位作者 祝彦均 吕恒康 张杰 《中国环境科学》 EI CAS CSCD 北大核心 2024年第7期3672-3681,共10页
以预脱碳污水和市政污水作为目标污水,建立了好氧段分段进水的新模式,通过调整进水分配比来优化好氧段C/N,以期实现短程硝化-厌氧氨氧化(PN/A)工艺在实际工况下的稳定运行.采用4组以好氧/缺氧/好氧/缺氧(O/A/O/A)模式运行的序批式反应器... 以预脱碳污水和市政污水作为目标污水,建立了好氧段分段进水的新模式,通过调整进水分配比来优化好氧段C/N,以期实现短程硝化-厌氧氨氧化(PN/A)工艺在实际工况下的稳定运行.采用4组以好氧/缺氧/好氧/缺氧(O/A/O/A)模式运行的序批式反应器(SBR),R1、R2、R3及R4以进水分配比(预脱碳污水:市政污水)分别为1:0、2:1、1:1及1:2的分段进水模式运行.结果表明,R1未能实现PN/A工艺,总氮去除率(NRE)仅为60.2%.随着进水分配比不断下降,R2、R3、R4分别在第34,30及36d实现PN/A工艺,NRE分别达到71.8%、80.3%及74.1%.其中R3系统处理性能最好且最稳定,厌氧氨氧化贡献率达到83.9%.污泥沉降性与粒径最佳.此外,高通量结果显示氨氧化菌(Nitrosomonas)和厌氧氨氧化菌(Candidatus_Kuenenia)丰度分别为2.74%和12.17%,且与好氧异养菌(AHB)形成了良好的协同作用.因此,分段进水模式在进水分配比为1:1时有利于实现稳定的PN/A工艺,此时各功能微生物可得到较好富集与平衡. 展开更多
关键词 分段进水 pn/A工艺 进水分配比 竞争性抑制
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DPF碳载量对重型车PN排放影响研究
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作者 李梁 马成功 张凡 《小型内燃机与车辆技术》 CAS 2024年第2期49-54,共6页
从DPF碳载量为0%时开始,直至DPF碳载量为100%,达到后处理再生状态结束共进行了8次PEMS试验。研究DPF碳载量对PN比排放的影响,根据瞬时车速和瞬时机动车比功率等参数对瞬态数据划分Bin网格,计算每次试验各个Bin的PN平均排放浓度和DPF平... 从DPF碳载量为0%时开始,直至DPF碳载量为100%,达到后处理再生状态结束共进行了8次PEMS试验。研究DPF碳载量对PN比排放的影响,根据瞬时车速和瞬时机动车比功率等参数对瞬态数据划分Bin网格,计算每次试验各个Bin的PN平均排放浓度和DPF平均温度的关系。试验结果表明,除最后一次发生再生的PEMS测试外,随着DPF碳载量的增大,PN比排放呈现先升高再降低的趋势;随着碳载量升高,Bin0、Bin1、Bin12以及Bin22等区间内每次试验的PN排放浓度相差不多。Bin13区间内的PN排放会随着碳载量的升高整体呈升高趋势。Bin23和Bin33区间内,PEMS试验的PN排放会随着碳载量的升高整体呈降低趋势。 展开更多
关键词 碳载量 pn比排放 DPF入口温度 PEMS试验
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短周期PN序列水声直扩系统抗单频干扰能力的变化规律与试验验证
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作者 王晓玮 周其斗 +2 位作者 唐永壮 谢志勇 刘文玺 《海军工程大学学报》 CAS 北大核心 2024年第2期43-49,共7页
对无法定量分析短周期PN序列直扩系统抗单频干扰性能的问题,首先通过理论推导得到单频干扰经相关处理产生的干扰分量;然后,结合直扩系统对单频干扰的处理增益,针对水声系统扩频序列周期较短的现实情况,提出了周期性PN序列水声直扩系统... 对无法定量分析短周期PN序列直扩系统抗单频干扰性能的问题,首先通过理论推导得到单频干扰经相关处理产生的干扰分量;然后,结合直扩系统对单频干扰的处理增益,针对水声系统扩频序列周期较短的现实情况,提出了周期性PN序列水声直扩系统抗单频干扰性能定量分析的理论表达式;最后,通过仿真和试验验证了理论表达式的正确性。结果表明:单频干扰经相关处理后得到的干扰序列呈直流或正弦分布;单频干扰对系统误码率的影响与信干比、干扰频偏、相位偏差以及扩频码本身结构有关,误码率随干扰相位偏差变化呈周期分布;在干扰频偏值为整数倍码元带宽的所有工况中,频偏为一倍码元带宽的单频干扰对系统影响最大;简明的理论表达式,对快速预报现实短码水声系统抗单频干扰性能的变化规律具有重要意义。 展开更多
关键词 水声通信 短周期pn序列 单频干扰 标准高斯近似
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CPSO优化PNN的陀螺故障诊断方法
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作者 张华强 贾明玉 +2 位作者 赵善飞 芦男 陈雨 《中国惯性技术学报》 EI CSCD 北大核心 2024年第6期630-636,共7页
针对惯性导航系统中的陀螺仪输出信号非线性、故障特征不明显的问题,为提高惯导系统中惯性器件的故障诊断正确率,提出一种基于改进粒子群算法(PSO)优化概率神经网络(PNN)的陀螺信号故障诊断方法。首先,针对光纤陀螺运行过程中常见的四... 针对惯性导航系统中的陀螺仪输出信号非线性、故障特征不明显的问题,为提高惯导系统中惯性器件的故障诊断正确率,提出一种基于改进粒子群算法(PSO)优化概率神经网络(PNN)的陀螺信号故障诊断方法。首先,针对光纤陀螺运行过程中常见的四种故障信号,建立数学模型并进行小波变换提取其故障特征系数;其次,使用Cubic混沌映射以及非线性递减的惯性权重系数对粒子群进行粒子更新,并用于概率神经网络的最优平滑因子选择;最后,训练概率神经网络对陀螺仪故障信号进行分类和诊断。离线测试结果表明,CPSO算法优化的PNN网络针对四种故障分类的平均正确率达到95.8%。 展开更多
关键词 粒子群优化算法 概率神经网络 陀螺故障诊断
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基于MATLAB的PN结形成过程蒙特卡罗程序研发
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作者 龚丽 赵宇 +8 位作者 王春龙 徐攀峰 刘雯 李一杰 梁友君 许媛媛 朱江 康晓民 康晓珅 《辽宁大学学报(自然科学版)》 CAS 2024年第2期179-183,共5页
本文基于蒙特卡罗随机行走的思想,用概率和随机抽样模拟PN结形成过程中载流子的运动以及动态分布,解决平衡态PN结电势所满足的泊松方程过于复杂、难以计算以及模拟的问题.利用MATLAB软件将演化过程中的载流子的运动过程可视化,并且将平... 本文基于蒙特卡罗随机行走的思想,用概率和随机抽样模拟PN结形成过程中载流子的运动以及动态分布,解决平衡态PN结电势所满足的泊松方程过于复杂、难以计算以及模拟的问题.利用MATLAB软件将演化过程中的载流子的运动过程可视化,并且将平衡态PN结的电势分布可视化.该方法可通过模拟载流子的运动规律及分布了解PN结的形成过程,进而及时对物理模型进行修正.该程序实现手段简便,物理图像清晰,可以用于半导体物理等相关课程的课堂教学. 展开更多
关键词 蒙特卡罗方法 pn 随机抽样 半导体器件模拟
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基于MIV-PSO-BPNN的掘进面风温预测方法
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作者 程磊 李正健 +2 位作者 贺智勇 史浩镕 王鑫 《河南理工大学学报(自然科学版)》 CAS 北大核心 2024年第6期11-17,共7页
目的为防治矿井热害,解决矿井掘进面风温预测问题,方法提出一种MIV算法优化的PSO-BPNN预测模型。通过利用MIV算法确定模型的输入变量,以BP网络建模,使用粒子群优化算法结合BP神经网络实现掘进工作面风流温度的预测,得到预测结果并与BPN... 目的为防治矿井热害,解决矿井掘进面风温预测问题,方法提出一种MIV算法优化的PSO-BPNN预测模型。通过利用MIV算法确定模型的输入变量,以BP网络建模,使用粒子群优化算法结合BP神经网络实现掘进工作面风流温度的预测,得到预测结果并与BPNN模型、PSO-BPNN模型、SVR模型相比较。结果结果表明:MIV-PSO-BPNN预测模型的相对误差为-0.47%~1.81%,分别优于PSO-BPNN、BPNN、SVR预测模型的-3.96%~1.93%,-5.54%~2.98%,-2.16%~2.95%,预测模型的误差为-0.1~0.5℃,表明预测值与实测值基本一致;与BPNN预测模型、PSO-BPNN预测模型、SVR预测模型相比,MIV-PSO-BPNN预测模型的预测结果平均绝对误差分别减少65%,54%,50%,均方误差分别减少88%,78%,69%,表明该预测模型的预测效果优于其他3种模型。结论所提模型适用于矿井掘进工作面风温的预测。 展开更多
关键词 BP神经网络 MIV算法 粒子群优化算法 风温预测 算法优化
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一种基于传输线理论的pn结二极管小信号模型
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作者 李翔 刘军 《半导体技术》 CAS 北大核心 2024年第3期218-225,共8页
为了精确表征毫米波频段pn结二极管的特性,提出了一种基于传输线理论的pn结二极管小信号模型。该模型包括表征pn结的本征部分和寄生部分。以量化的pn结耗尽区串联电阻作为中间项,通过非线性传输线理论近似方法,推导出全新的pn结二极管... 为了精确表征毫米波频段pn结二极管的特性,提出了一种基于传输线理论的pn结二极管小信号模型。该模型包括表征pn结的本征部分和寄生部分。以量化的pn结耗尽区串联电阻作为中间项,通过非线性传输线理论近似方法,推导出全新的pn结二极管小信号模型的拓扑结构。通过导纳参数和阻抗参数的参数解析提取方法,提取等效电路中各元件参数值。使用某磷化铟(InP)工艺线加工所得2×3μm、8×8μm、4×16μm二极管的散射参数数据进行验证。结果表明,在1~110 GHz频率范围内,不同偏压的模型仿真结果与测试结果均吻合较好,同时也能表明模型在毫米波频段内有良好的适用性。 展开更多
关键词 毫米波频段 pn 耗尽区串联电阻 传输线理论 参数解析提取
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PN结光电子器件:科研创新与教学融合
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作者 石凯熙 姜振峰 +2 位作者 李亚妮 李金华 李静 《物理实验》 2024年第9期27-32,共6页
阐述了低维材料在光电子器件领域的创新发展,设计了以PN结光电探测器为核心的本科生实验模块.通过光电测试系统获得了PN结光电探测器的光电流响应,并对其机理进行了深度分析.学生在教师的指导下完成材料制备、器件测试以及理论分析,促... 阐述了低维材料在光电子器件领域的创新发展,设计了以PN结光电探测器为核心的本科生实验模块.通过光电测试系统获得了PN结光电探测器的光电流响应,并对其机理进行了深度分析.学生在教师的指导下完成材料制备、器件测试以及理论分析,促进了科研成果向本科教学的转化,也增强了学生对PN结关键概念的理解. 展开更多
关键词 pn 异质结 光电探测器 低维材料
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环保型粘合剂PN760对丁苯橡胶胶料性能及其与聚酯帘线粘合性能的影响
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作者 孟祥泽 康乐 +1 位作者 刘莉 沈梅 《橡胶工业》 CAS 2024年第11期837-843,共7页
采用间甲酚-甲醛-胶乳(CFL)浸渍体系和封端水性聚氨酯胶乳(WPUL)浸渍体系对聚酯[聚对苯二甲酸乙二醇酯(PET)]帘线进行表面改性处理,探究环保型粘合剂PN760(简称PN760)对丁苯橡胶(SBR)胶料性能及其与PET帘线粘合性能的影响。结果表明:PN... 采用间甲酚-甲醛-胶乳(CFL)浸渍体系和封端水性聚氨酯胶乳(WPUL)浸渍体系对聚酯[聚对苯二甲酸乙二醇酯(PET)]帘线进行表面改性处理,探究环保型粘合剂PN760(简称PN760)对丁苯橡胶(SBR)胶料性能及其与PET帘线粘合性能的影响。结果表明:PN760对SBR胶料的加工安全性能和物理性能影响不大,但使SBR胶料的硫化速率降低;PN760对SBR胶料与CFL和WPUL浸渍体系处理的PET帘线粘合性能均有明显的改善效果,PN760用量为4份时,SBR胶料与PET帘线的粘合性能最好;与采用CFL浸渍体系处理的PET帘线相比,SBR胶料与采用WPUL浸渍体系处理的PET帘线的粘合性能稍差。 展开更多
关键词 粘合剂pn760 环保型 丁苯橡胶 聚酯帘线 粘合性能
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栅控内嵌反偏PN结的单器件同或门电路的研究
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作者 娄存义 刘溪 《电子制作》 2024年第17期115-117,共3页
在实现同或门电路时,为减少器件的使用以及使用简便,提出了栅控内嵌反偏PN结的单器件同或门电路(GPN-XNOR)。通过silvaco软件建模与仿真,分析其工作原理。GPN-XNOR是通过控制栅极电压来控制其下方体硅区的多数载流子类型,利用漏极电压实... 在实现同或门电路时,为减少器件的使用以及使用简便,提出了栅控内嵌反偏PN结的单器件同或门电路(GPN-XNOR)。通过silvaco软件建模与仿真,分析其工作原理。GPN-XNOR是通过控制栅极电压来控制其下方体硅区的多数载流子类型,利用漏极电压实现PN结的正偏与反偏,进而实现器件的导通与截止。在漏极电压为正,栅压的极性相同时,器件可以正常导通,进一步实现同或功能。如果栅压极性不同,器件不会导通。GPN-XNOR结构与传统的MOS场效应晶体管不同之处在于源区采用了N型重掺杂区,漏区采用了P型重掺杂区,源漏掺杂类型不相同。相比于CMOS工艺实现同或功能来说,该设计具有材料用量少,占用芯片面积少的特点,只需要一个器件就可以实现同或XNOR逻辑功能,并且不用转换栅极电压的极性就可以实现同或门电路。 展开更多
关键词 pn XNOR 栅极 掺杂 栅控
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基于新型PVA/PA/Fe凝胶载体的PN/A工艺研究
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作者 靳德源 何浩宸 +3 位作者 田文清 李小锋 李党勇 梁继东 《环境科学与技术》 CAS CSCD 北大核心 2024年第5期1-9,共9页
部分硝化-厌氧氨氧化(PN/A)是低碳低耗的污水自养脱氮工艺。然而,如何在反应器内有效截留缓慢生长的厌氧氨氧化菌(AnAOB),并创建厌氧菌AnAOB与好氧氨氧化菌(AOB)的共生生境是构建PN/A稳定运行的关键。该研究拟采用负载铁的多孔生物载体P... 部分硝化-厌氧氨氧化(PN/A)是低碳低耗的污水自养脱氮工艺。然而,如何在反应器内有效截留缓慢生长的厌氧氨氧化菌(AnAOB),并创建厌氧菌AnAOB与好氧氨氧化菌(AOB)的共生生境是构建PN/A稳定运行的关键。该研究拟采用负载铁的多孔生物载体PVA/PA/Fe促进AnAOB的截留及与AOB协同共生,实现PN/A的快速启动和高效运行。结果表明,相较于未添加载体和添加PVA/PA载体,PVA/PA/Fe显著促进了AnAOB的截留及与AOB协同共生脱氮,AnAOB丰度相较对照组在Anammox阶段提高5.93%,在PN/A阶段提高7.81%;在Anammox阶段添加PVA/PA与PVA/PA/Fe载体的反应器表现出更良好的抗冲击负荷的性能,NLR可达1.01 kg-N/(m^(3)·d),而对照组只能稳定在0.61 kg-N/(m^(3)·d);加入PVA/PA/Fe载体的反应器在PN/A阶段启动7 d时就达到RETN>85%,而对照组与添加PVA/PA载体的反应器在经过12 d时才达到此处理效果。上述结果为PN/A工艺的实际应用提供了理论和技术指导。 展开更多
关键词 PVA/PA/Fe凝胶载体 ANAMMOX pn/A Candidatus_Kuenenia
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基于IPSO-BPNN的楼宇屋顶光伏出力功率超短期预测
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作者 鲁娟 何鑫 +1 位作者 李明海 邓琨升 《现代建筑电气》 2024年第4期45-50,62,共7页
在建筑光伏一体化技术的背景下,准确预测屋顶光伏输出功率对于优化建筑能源管理和确保光伏电力的稳定并网至关重要。提出了一种基于IPSO-BPNN的楼宇屋顶光伏出力功率超短期预测模型,该模型引入Sine混沌序列初始化和精英粒子反向学习策略... 在建筑光伏一体化技术的背景下,准确预测屋顶光伏输出功率对于优化建筑能源管理和确保光伏电力的稳定并网至关重要。提出了一种基于IPSO-BPNN的楼宇屋顶光伏出力功率超短期预测模型,该模型引入Sine混沌序列初始化和精英粒子反向学习策略,改进了基本的PSO算法,并利用此算法对基本BPNN模型的超参数进行优化,从而实现了对屋顶光伏出力功率更加准确的预测。预测模型性能测试实验表明,所提出的IPSO-BPNN预测模型在不同季节的预测准确性和稳定性都有显著提高。该模型能够准确预测屋顶光伏发电功率,为建筑光伏一体化系统的稳定运行和能源管理提供切实可行的解决方案。 展开更多
关键词 建筑光伏一体化 屋顶光伏 反向传播网络 粒子群算法 光伏出力功率预测
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Study of deep transportation and plugging performance of deformable gel particles in porous media
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作者 Wen-Jing Zhao Jing Wang +1 位作者 Zhong-Yang Qi Hui-Qing Liu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期962-973,共12页
Deformable gel particles(DGPs) possess the capability of deep profile control and flooding. However, the deep migration behavior and plugging mechanism along their path remain unclear. Breakage, an inevitable phenomen... Deformable gel particles(DGPs) possess the capability of deep profile control and flooding. However, the deep migration behavior and plugging mechanism along their path remain unclear. Breakage, an inevitable phenomenon during particle migration, significantly impacts the deep plugging effect. Due to the complexity of the process, few studies have been conducted on this subject. In this paper, we conducted DGP flow experiments using a physical model of a multi-point sandpack under various injection rates and particle sizes. Particle size and concentration tests were performed at each measurement point to investigate the transportation behavior of particles in the deep part of the reservoir. The residual resistance coefficient and concentration changes along the porous media were combined to analyze the plugging performance of DGPs. Furthermore, the particle breakage along their path was revealed by analyzing the changes in particle size along the way. A mathematical model of breakage and concentration changes along the path was established. The results showed that the passage after breakage is a significant migration behavior of particles in porous media. The particles were reduced to less than half of their initial size at the front of the porous media. Breakage is an essential reason for the continuous decreases in particle concentration, size, and residual resistance coefficient. However, the particles can remain in porous media after breakage and play a significant role in deep plugging. Higher injection rates or larger particle sizes resulted in faster breakage along the injection direction, higher degrees of breakage, and faster decreases in residual resistance coefficient along the path. These conditions also led to a weaker deep plugging ability. Smaller particles were more evenly retained along the path, but more particles flowed out of the porous media, resulting in a poor deep plugging effect. The particle size is a function of particle size before injection, transport distance, and different injection parameters(injection rate or the diameter ratio of DGP to throat). Likewise, the particle concentration is a function of initial concentration, transport distance, and different injection parameters. These models can be utilized to optimize particle injection parameters, thereby achieving the goal of fine-tuning oil displacement. 展开更多
关键词 Physical simulation Deformable gel particle BREAKAGE Particle size Residual resistance coefficient
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Mathematical modeling and simulations of stress mitigation by coating polycrystalline particles in lithium-ion batteries 被引量:1
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作者 N.IQBAL J.CHOI +2 位作者 S.F.SHAH C.LEE S.LEE 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第6期947-962,共16页
A chemo-mechanical model is developed to investigate the effects on the stress development of the coating of polycrystalline Ni-rich LiNixMnyCo_(z)O_(2)(x≥0.8)(NMC)particles with poly(3,4-ethylenedioxythiophene)(PEDO... A chemo-mechanical model is developed to investigate the effects on the stress development of the coating of polycrystalline Ni-rich LiNixMnyCo_(z)O_(2)(x≥0.8)(NMC)particles with poly(3,4-ethylenedioxythiophene)(PEDOT).The simulation results show that the coating of primary NMC particles significantly reduces the stress generation by efficiently accommodating the volume change associated with the lithium diffusion,and the coating layer plays roles both as a cushion against the volume change and a channel for the lithium transport,promoting the lithium distribution across the secondary particles more homogeneously.Besides,the lower stiffness,higher ionic conductivity,and larger thickness of the coating layer improve the stress mitigation.This paper provides a mathematical framework for calculating the chemo-mechanical responses of anisotropic electrode materials and fundamental insights into how the coating of NMC active particles mitigates stress levels. 展开更多
关键词 lithium-ion battery(LIB) polycrystalline particle COATING finite element simulation Ni-rich LiNixMnyCo_(z)O_(2)(x>0.8)(NMC)
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Mass transfer enhancement and hydrodynamic performance with wire mesh coupling solid particles in bubble column reactor
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作者 Chuanjun Di Jipeng Dong +3 位作者 Fei Gao Guanghui Chen Pan Zhang Jianlong Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期195-205,共11页
It is of vital significance to investigate mass transfer enhancements for chemical engineering processes.This work focuses on investigating the coupling influence of embedding wire mesh and adding solid particles on b... It is of vital significance to investigate mass transfer enhancements for chemical engineering processes.This work focuses on investigating the coupling influence of embedding wire mesh and adding solid particles on bubble motion and gas-liquid mass transfer process in a bubble column.Particle image velocimetry(PIV)technology was employed to analyze the flow field and bubble motion behavior,and dynamic oxygen absorption technology was used to measure the gas-liquid volumetric mass transfer coefficient(kLa).The effect of embedding wire mesh,adding solid particles,and wire mesh coupling solid particles on the flow characteristic and kLa were analyzed and compared.The results show that the gas-liquid interface area increases by 33%-72%when using the wire mesh coupling solid particles strategy compared to the gas-liquid two-phase flow,which is superior to the other two strengthening methods.Compared with the system without reinforcement,kLa in the bubble column increased by 0.5-1.8 times with wire mesh coupling solid particles method,which is higher than the sum of kLa increases with inserting wire mesh and adding particles,and the coupling reinforcement mechanism for affecting gas-liquid mass transfer process was discussed to provide a new idea for enhancing gas-liquid mass transfer. 展开更多
关键词 Fluid mechanics BUBBLE Mass transfer Wire mesh coupling solid particles Particle image velocimetry Hydrodynamics
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电子学仿真在PN结教学中的运用探析
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作者 郁建灿 高平奇 《教育教学论坛》 2024年第24期122-127,共6页
在PN结等半导体器件中,载流子浓度表现出复杂的时空演化特征。目前,普遍采用理论分析的教学方法,虽然使学生感受到了复杂问题处理的技巧,却失去了对器件工作过程的全面认识。提出在器件教学过程中融入电子学仿真的研究方法,使学生掌握... 在PN结等半导体器件中,载流子浓度表现出复杂的时空演化特征。目前,普遍采用理论分析的教学方法,虽然使学生感受到了复杂问题处理的技巧,却失去了对器件工作过程的全面认识。提出在器件教学过程中融入电子学仿真的研究方法,使学生掌握理解和探索器件的有力工具。比较了理论分析与数值仿真两种方法的优点和缺点,阐述了电子学仿真软件在PN结教学中的作用,并举例运用仿真手段剖析了教材中的疑点。相信仿真工具将激发学生的学习兴趣,促进从注重知识积累的学习习惯到自主探索的学习范式的转变,提升课程教学效果,并缩短从课程学习到科研实践的路径。 展开更多
关键词 电子学仿真 pn 理论分析
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国六柴油机PN排放试验研究
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作者 兰亚 张勇 +2 位作者 宋军太 房瑞雪 王祥吉 《内燃机与配件》 2024年第14期19-21,共3页
为探究国六柴油机开式排放循环中PN排放的影响因素,本文以某国六轻型柴油机为研究对象,研究不同漏气量下WHTC开式排放循环中PN排放量级,以及开式循环管路加热装置、冷态WHTC试验前的不同凉车时间、呼吸器内部毛毡结构等参数条件对排放循... 为探究国六柴油机开式排放循环中PN排放的影响因素,本文以某国六轻型柴油机为研究对象,研究不同漏气量下WHTC开式排放循环中PN排放量级,以及开式循环管路加热装置、冷态WHTC试验前的不同凉车时间、呼吸器内部毛毡结构等参数条件对排放循环PN尾排的影响。研究结果表明:(1)柴油机本体漏气量对开式PN排放的影响较显著;而呼吸器内部毛毡结构对开式PN排放影响较小;(2)开式循环下,开式管路的加热装置对冷态WHTC的PN排放的影响较显著;而对热态WHTC的PN排放影响较小;(3)开式冷态WHTC试验前凉车时间的增加,会导致冷态WHTC的PN排放增加。 展开更多
关键词 pn排放 柴油机 漏气量 开式循环 加热装置
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Electric field and force characteristic of dust aerosol particles on the surface of high-voltage transmission line
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作者 刘滢格 李兴财 +2 位作者 王娟 马鑫 孙文海 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期368-378,共11页
High-voltage transmission lines play a crucial role in facilitating the utilization of renewable energy in regions prone to desertification. The accumulation of atmospheric particles on the surface of these lines can ... High-voltage transmission lines play a crucial role in facilitating the utilization of renewable energy in regions prone to desertification. The accumulation of atmospheric particles on the surface of these lines can significantly impact corona discharge and wind-induced conductor displacement. Accurately quantifying the force exerted by particles adhering to conductor surfaces is essential for evaluating fouling conditions and making informed decisions. Therefore, this study investigates the changes in electric field intensity along branched conductors caused by various fouling layers and their resulting influence on the adhesion of dust particles. The findings indicate that as individual particle size increases, the field strength at the top of the particle gradually decreases and eventually stabilizes at approximately 49.22 k V/cm, which corresponds to a field strength approximately 1.96 times higher than that of an unpolluted transmission line. Furthermore,when particle spacing exceeds 15 times the particle size, the field strength around the transmission line gradually decreases and approaches the level observed on non-adhering surface. The electric field remains relatively stable. In a triangular arrangement of three particles, the maximum field strength at the tip of the fouling layer is approximately 1.44 times higher than that of double particles and 1.5 times higher compared to single particles. These results suggest that particles adhering to the transmission line have a greater affinity for adsorbing charged particles. Additionally, relevant numerical calculations demonstrate that in dry environments, the primary adhesion forces between particles and transmission lines follow an order of electrostatic force and van der Waals force. Specifically, at the minimum field strength, these forces are approximately74.73 times and 19.43 times stronger than the gravitational force acting on the particles. 展开更多
关键词 high-voltage current electric field aerosol particles force characteristic
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An Original Didactic about Standard Model: “The Particles’ Geometric Model” (Leptons and Bosons)
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作者 Giovanni Guido Abele Bianchi Gianluigi Filippelli 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1424-1449,共26页
This work shows a didactic model representative (GPM) of the particles described in the Standard Model (SM). Particles are represented by geometric forms corresponding to geometric structures of coupled quantum oscill... This work shows a didactic model representative (GPM) of the particles described in the Standard Model (SM). Particles are represented by geometric forms corresponding to geometric structures of coupled quantum oscillators. From the didactic hypotheses of the model emerges an in-depth phenomenology of particles that is fully compatible with that of SM. Thanks to this model, we can calculate “geometrically” the mass of Higgs’s Boson and the mass of the pair “muon and muonic neutrino”, and, by the geometric shapes of leptons and bosons, we can also solve crucial aspects of SM physics as the neutrinos’ oscillations and the intrinsic chirality of the neutrino and antineutrino. 展开更多
关键词 Golden Particle QUARK LEPTONS IQuO Lattice BOSON HIGGS CHIRALITY
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Extending homogeneous fluidization flow regime of Geldart-A particles by exerting axial uniform and steady magnetic field
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作者 Qiang Zhang Wankun Liu +1 位作者 Hengjun Gai Quanhong Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期169-177,共9页
The homogeneous/particulate fluidization flow regime is particularly suitable for handling the various gas–solid contact processes encountered in the chemical and energy industry.This work aimed to extend such a regi... The homogeneous/particulate fluidization flow regime is particularly suitable for handling the various gas–solid contact processes encountered in the chemical and energy industry.This work aimed to extend such a regime of Geldart-A particles by exerting the axial uniform and steady magnetic field.Under the action of the magnetic field,the overall homogeneous fluidization regime of Geldart-A magnetizable particles became composed of two parts:inherent homogeneous fluidization and newly-created magnetic stabilization.Since the former remained almost unchanged whereas the latter became broader as the magnetic field intensity increased,the overall homogeneous fluidization regime could be extended remarkably.As for Geldart-A nonmagnetizable particles,certain amount of magnetizable particles had to be premixed to transmit the magnetic stabilization.Among others,the mere addition of magnetizable particles could broaden the homogeneous fluidization regime.The added content of magnetizable particles had an optimal value with smaller/lighter ones working better.The added magnetizable particles might raise the ratio between the interparticle force and the particle gravity.After the magnetic field was exerted,the homogeneous fluidization regime was further expanded due to the formation of magnetic stabilization flow regime.The more the added magnetizable particles,the better the magnetic performance and the broader the overall homogeneous fluidization regime.Smaller/lighter magnetizable particles were preferred to maximize the magnetic performance and extend the overall homogeneous fluidization regime.This phenomenon could be ascribed to that the added magnetizable particles themselves became more Geldart-A than-B type as their density or size decreased. 展开更多
关键词 FLUIDIZED-BED FLUIDIZATION Geldart-A particles Flow regimes EXTEND Magnetic stabilization
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