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The parallel-plate resonator:An RF probe for MR and MRI studies over a wide frequency range 被引量:1
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作者 Andres Ramírez Aguilera Kevin J.Sanders +1 位作者 Gillian R.Goward Bruce J.Balcom 《Magnetic Resonance Letters》 2023年第4期306-318,共13页
We explore the use of the parallel-plate resonator for the study of thin cuboid samples over a wide range of magnetic resonance frequencies.The parallel-plate resonator functions at frequencies from tens to hundreds o... We explore the use of the parallel-plate resonator for the study of thin cuboid samples over a wide range of magnetic resonance frequencies.The parallel-plate resonator functions at frequencies from tens to hundreds of MHz.Seven parallel-plate resonators are presented and discussed in a frequency range from 8 to 500 MHz.Magnetic resonance experiments were performed on both horizontal and vertical bore magnet systems with lithium and hydrogen nuclei.Parallel-plate radiofrequency(RF)probes are easy to build and easy to optimize.Experiments and simulations showed good sensitivity of the parallel-plate RF probe geometry with a small decrease in sensitivity at higher frequencies. 展开更多
关键词 parallel-plate resonator Optimization Magnetic resonance/magnetic resonance imaging(MR/MRI) BATTERIES
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OPTIMIZATION OF TRANSIENT FEEDING TO PARALLEL-PLATE TRANSMISSION LINES FROM COAXIAL LINE 被引量:4
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作者 Tian Chunming Wang Jianguo Meng Fenxia Zhang Maoyu Ge Debiao(Department of Physics, Xidian University, Xi’an 710071) (Northwest Institute of Nuclear Technology, P. O. Box 69-15, Xi’an 710024) 《Journal of Electronics(China)》 2001年第3期281-284,共4页
The transient feeding to parallel-plate transmission lines from coaxial line is optimized by using the Finite-Difference Time-Domain (FDTD) method and a simple FDTD feed model. Observing the reflected voltages, this l... The transient feeding to parallel-plate transmission lines from coaxial line is optimized by using the Finite-Difference Time-Domain (FDTD) method and a simple FDTD feed model. Observing the reflected voltages, this letter presents the optimal feeding position and ratio of width to height for a given input impedance of the coaxial line. 展开更多
关键词 FDTD method parallel-plate TRANSMISSION LINES
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ON ANALYSIS OF THE STEADY FLOW IN AN IRRECTANGULARPARALLEL-PLATE FLOW CHAMBER 被引量:1
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作者 覃开荣 姜伟元 +1 位作者 李惜惜 柳兆荣 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第9期851-859,共9页
The parallel-plate flow chamber (PPFC), of which the height is far smaller than its own length and width, is one of the main apparatus for the in vitro study of the mechanical behaviors of cultured cells at the bottom... The parallel-plate flow chamber (PPFC), of which the height is far smaller than its own length and width, is one of the main apparatus for the in vitro study of the mechanical behaviors of cultured cells at the bottom of PPFC undergoing shear stress. The PPFC of which the upper and lower plates are rectangular is usually used by research workers, and the flow field in this kind of PPFC (except for the regions near the entrance and exit) is uniform([1]), so only the effect the shear stress with one value has on cultured cells can be observed during each experiment. A kind of PPFC of which the upper and lower plates are not rectangular is proposed in this paper. The distributions of the velocities inside and the shear stresses at the bottom of the chamber are given by analyzing the flow field of the steady flow in the PPFC. The results show that the mechanical behaviors of cultured cells undergoing the shear stresses with various values may be simultaneously observed by the use of this kind of irrectangular PPFC. The theoretical and experimental results obtained by Ultrasonic Doppler Technique show good agreement. 展开更多
关键词 irrectangular parallel-plate flow chamber shear stress steady flow cell's mechanical behaviors
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MULTI-MODE NETWORK ANALYSIS FOR DISCONTINUITIES IN PARALLEL-PLATE WAVEGUIDES PARTIALLY FILLED WITH MULTI CHIRAL RODS
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作者 Dong Jianfeng Xu Shanjia 《Journal of Electronics(China)》 2006年第5期748-752,共5页
The reflection and transmission characteristics of the guided modes in parallel-plate waveguides partially filled with one or multi chiral rods have been investigated by a method, which combines the multi- mode networ... The reflection and transmission characteristics of the guided modes in parallel-plate waveguides partially filled with one or multi chiral rods have been investigated by a method, which combines the multi- mode network theory with a rigorous mode matching procedure. The formulas of the reflection and transmis- sion coefficient matrix are derived. The numerical results for different cases are presented and have indicated that the chirality parameters and the geometrical dimensions of the chiral rods have significant influence on the reflection and transmission characteristics of the guided modes. 展开更多
关键词 Chiral medium parallel-plate waveguide DISCONTINUITY Multimode network Mode matching
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ANALYSIS OF PULSATILE FLOW IN THE PARALLEL-PLATE FLOW CHAMBER WITH SPATIAL SHEAR STRESS GRADIENT 被引量:5
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作者 QIN Kai-rong HU Xu-qu LIU Zhao-rong 《Journal of Hydrodynamics》 SCIE EI CSCD 2007年第1期113-120,共8页
The Parallel-Plate Flow Chamber (PPFC), of which the height is far smaller than its own length and width, is one of the main apparatus for the in-vitro study of the mechanical behavior of cultured vascular Endotheli... The Parallel-Plate Flow Chamber (PPFC), of which the height is far smaller than its own length and width, is one of the main apparatus for the in-vitro study of the mechanical behavior of cultured vascular Endothelical Cells (ECs) exposed to fluid shear stress. The steady flow in different kinds of PPFC has been extensively investigated, whereas, the pulsatile flow in the PPFC has received little attention. In consideration of the characteristics of geometrical size and pulsatile flow in the PPFC, the 3-D pulsatile flow was decomposed into a 2-D pulsatile flow in the vertical plane, and an incompressible plane potential flow in the horizontal plane. A simple method was then proposed to analyze the pulsatile flow in the PPFC with spatial shear stress gradient. On the basis of the method, the pulsatile fluid shear stresses in several reported PPFCs with spatial shear stress gradients were calculated. The results were theoretically meaningful for applying the PPFCs in-vitro, to simulate the pulsatile fluid shear stress environment, to which cultured ECs were exposed. 展开更多
关键词 Pulsatile flow fluid shear stress spatialshear stress gradient parallel-plate flow chamber culturedendothelial cells cell mechanics
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Removal of antibiotics in a parallel-plate thin-film-photocatalytic reactor: Process modeling and evolution of transformation by-products and toxicity 被引量:2
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作者 Can Burak?zkal Zacharias Frontistis +3 位作者 Maria Antonopoulou Ioannis Konstantinou Dionissios Mantzavinos Süreyya Meric 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第10期114-122,共9页
Photocatalytic degradation of sulfamethoxazole(SMX) antibiotic has been studied under recycling batch and homogeneous flow conditions in a thin-film coated immobilized system namely parallel-plate(PPL) reactor. Ex... Photocatalytic degradation of sulfamethoxazole(SMX) antibiotic has been studied under recycling batch and homogeneous flow conditions in a thin-film coated immobilized system namely parallel-plate(PPL) reactor. Experimentally designed, statistically evaluated with a factorial design(FD) approach with intent to provide a mathematical model takes into account the parameters influencing process performance. Initial antibiotic concentration, UV energy level, irradiated surface area, water matrix(ultrapure and secondary treated wastewater) and time, were defined as model parameters. A full of 2~5 experimental design was consisted of 32 random experiments. PPL reactor test experiments were carried out in order to set boundary levels for hydraulic, volumetric and defined defined process parameters. TTIP based thin-film with polyethylene glycol + TiO2 additives were fabricated according to pre-described methodology. Antibiotic degradation was monitored by High Performance Liquid Chromatography analysis while the degradation products were specified by LC–TOF-MS analysis. Acute toxicity of untreated and treated SMX solutions was tested by standard Daphnia magna method. Based on the obtained mathematical model, the response of the immobilized PC system is described with a polynomial equation. The statistically significant positive effects are initial SMX concentration,process time and the combined effect of both, while combined effect of water matrix and irradiated surface area displays an adverse effect on the rate of antibiotic degradation by photocatalytic oxidation. Process efficiency and the validity of the acquired mathematical model was also verified for levofloxacin and cefaclor antibiotics. Immobilized PC degradation in PPL reactor configuration was found capable of providing reduced effluent toxicity by simultaneous degradation of SMX parent compound and TBPs. 展开更多
关键词 Thin-film photocatalysis Sulfamethoxazole (SMX) Levofloxacin (LVX) Cefaclor (CFL) Factorial design Modeling parallel-plate reactor
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A portable and low-cost parallel-plate capacitor sensor for alkali and heavy metal ions detection
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作者 Septia Kholimatussadiah Tri Anggono Prijo 《Journal of Advanced Dielectrics》 CAS 2018年第4期28-34,共7页
A portable and low-cost design of parallel-plate capacitor sensor is proposed and investigated for detection of heavy and alkali metal ions concentration in liquid solution.The application of a thin and long-sided par... A portable and low-cost design of parallel-plate capacitor sensor is proposed and investigated for detection of heavy and alkali metal ions concentration in liquid solution.The application of a thin and long-sided parallel PCB plate allows one to measure the dielectric response of each sample through capacitive sensing technique.The measurements were based on the peak output voltage corresponding to the capacitance of the output measured by an oscilloscope with metal ions concentration of the solution varying from 0 to 10 ppm and input frequency ranging from 1 kHz to 10 MHz.The ICF of Li,Na and K in chloride solution was 2.4,2.1 and 1.9 MHz,respectively.The ICF of Na and K in hydroxide solution was 1.5 MHz and 1.1 MHz,respectively,while the ICF of Pb(NO_(3))_(2)was 490 kHz.The detected ICF was applied to further construct the portable sensor system,which is simple in design,low-cost in fabrication and easy to operate.The finding of ICF of each chemical element is necessary to solve the selectivity challenge of the capacitance-based sensor,which will be appropriate for chemical,environmental and engineering applications. 展开更多
关键词 Capacitive sensing capacitor sensor characteristic frequency metal ions detection parallel-plate capacitor.
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Multinuclear MR and MRI study of lithium-ion cells using a variable field magnet and a fixed frequency RF probe
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作者 Andrés Ramírez Aguilera Florin Marica +4 位作者 Kevin J.Sanders Md Al Raihan C.Adam Dyker Gillian R.Goward Bruce J.Balcom 《Magnetic Resonance Letters》 2024年第1期10-20,共11页
An exploratory multinuclear magnetic resonance(MR)and magnetic resonance imaging(MRI)study was performed on lithium-ion battery cells with ^(7)Li,^(19)F,and ^(1)H measurements.A variable field superconducting magnet w... An exploratory multinuclear magnetic resonance(MR)and magnetic resonance imaging(MRI)study was performed on lithium-ion battery cells with ^(7)Li,^(19)F,and ^(1)H measurements.A variable field superconducting magnet with a fixed frequency parallel-plate radiofrequency(RF)probe was employed in the study.The magnetic field was changed to set the resonance frequency of each nucleus to the fixed RF probe frequency of 33.7 MHz.Two cartridge-like lithium-ion cells,with graphite anodes and LiNi_(0.5)Mn_(0.3)Co_(0.2)O_(2)(NMC)cathodes,were interrogated.One cell was pristine,and one was charged to a cell voltage of 4.2 V.The results presented demonstrate the great potential of the variable field magnet approach in multinuclear measurement of lithium-ion batteries.These methods open the door for developing faster and simpler methods for detecting,quantifying,and interpreting MR and MRI data from lithium-ion and other batteries. 展开更多
关键词 Multinuclear MR/MRI Variable field magnet Lithium-ion battery parallel-plate rf probe
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钢板削弱型叠层橡胶支座力学性能试验研究
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作者 马乾瑛 李冰冰 业嘉超 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2024年第7期1436-1445,1478,共11页
结合厚层橡胶支座和普通叠层橡胶支座的优点设计新型钢板削弱型叠层橡胶支座,通过调节环形钢板的总数和位置进行支座水平和竖向刚度的有效控制.选择3种中心橡胶层厚度的钢板削弱型叠层橡胶支座,分析所设计支座的滞回特性、刚度特性和耗... 结合厚层橡胶支座和普通叠层橡胶支座的优点设计新型钢板削弱型叠层橡胶支座,通过调节环形钢板的总数和位置进行支座水平和竖向刚度的有效控制.选择3种中心橡胶层厚度的钢板削弱型叠层橡胶支座,分析所设计支座的滞回特性、刚度特性和耗能特性.基于串-并联模型,构建水平和竖向刚度的计算模型.试验结果表明,相比普通叠层橡胶支座,钢板削弱型叠层橡胶支座的水平和竖向刚度更低,水平和竖向耗能比更高,滞回曲线更光滑饱满.所建模型的计算结果与试验结果的一致性较好,误差绝对值不超过10%.所建模型在评估钢板削弱型叠层橡胶支座的水平和竖向刚度方面具有较高的精度和适用性. 展开更多
关键词 橡胶支座 钢板削弱 串-并联模型 三维隔震 滞回特性
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平行板微通道中一类不可压缩微极性流体在高Zeta势下的时间周期电渗流
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作者 于欣如 崔继峰 +2 位作者 陈小刚 慕江勇 乔煜然 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第16期130-142,共13页
在高Zeta势下,研究平行板微通道中一类不可压缩微极性流体的时间周期电渗流.在不使用DebyeHüickel线性近似条件下,利用有限差分法数值求解非线性Poisson-Boltzmann方程和不可压缩微极性流体的连续性方程、动量方程、角动量方程及... 在高Zeta势下,研究平行板微通道中一类不可压缩微极性流体的时间周期电渗流.在不使用DebyeHüickel线性近似条件下,利用有限差分法数值求解非线性Poisson-Boltzmann方程和不可压缩微极性流体的连续性方程、动量方程、角动量方程及本构方程,在低Zeta势下将所得结果与使用Debye-Hückel线性近似得到的解析解比较,证明本文数值方法是可行的;讨论高Zeta势下电动宽度m、电振荡频率Ω、微极性参数k1等无量纲参数对不可压缩微极性流体的速度和微旋转效应的影响.研究表明:1)随着Zeta势的增大,微极性流体的速度、微旋转、体积流量、微旋强度以及剪切应力增大,说明与低Zeta势相比,高Zeta势对微极性流体电渗流有显著的促进作用.2)在高Zeta势下,随着微极性参数的增大,微极性流体的速度减小,但是对微旋转效应呈现先增强后减弱的趋势.3)在高Zeta势下,当电振荡频率较低(小于1)时,电动宽度的增大促进微极性流体的流动,但抑制其微旋转;当电振荡频率较高(大于1)时,电动宽度的增大抑制微极性流体的流动及微旋转,但促进体积流量快速增大并趋于恒定.4)在高Zeta势下,当电振荡频率较低(小于1)时,微极性流体电渗流速度和微旋转随着电振荡频率的变化呈现明显的振荡变化趋势,但是速度和微旋转的峰值、体积流量及微旋强度均保持不变;当电振荡频率较高(大于1)时,随着电振荡频率的增大,微极性流体电渗流速度和微旋转的幅值减小,体积流量及微旋强度减小直至趋于零.5)在高Zeta势下,壁面剪切应力σ21及σ12的幅值随电动宽度的增大而增大;当电振荡频率较低(小于1)时,壁面剪切应力σ21与σ12不随电振荡频率的增大而变化,均取恒定值,且微极性参数的取值不影响壁面剪切应力σ21的幅值;当电振荡频率较高(大于1)时,壁面剪切应力σ21及σ12的幅值随电振荡频率的增大而减小,且壁面剪切应力σ21的幅值随着微极性参数的增大而减小,而壁面剪切应力σ12的振幅随着微极性参数的增大而线性减小. 展开更多
关键词 微极性流体 ZETA 电渗流 平行板微通道 有限差分法
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基于标准场法的低频电场计量技术探讨
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作者 赵品彰 冯铁英 +2 位作者 孙剑辉 陈雨龙 宋光明 《计量学报》 CSCD 北大核心 2024年第8期1216-1221,共6页
为了实现低频电场测量仪的校准,探讨了基于标准场法的低频电场计量技术。描述了低频电场测量仪的结构和工作原理,分析了应用平行板产生可计算标准电场的方法,研究构建了校准系统。应用该系统进行了校准测量实验,分析了测量误差来源,评... 为了实现低频电场测量仪的校准,探讨了基于标准场法的低频电场计量技术。描述了低频电场测量仪的结构和工作原理,分析了应用平行板产生可计算标准电场的方法,研究构建了校准系统。应用该系统进行了校准测量实验,分析了测量误差来源,评估了测量结果的不确定度。将实验结果与应用横电磁波室法的测量结果作了比较,数据表明该校准系统的测量结果合理,满足低频电场测量仪的校准要求。 展开更多
关键词 电学计量 低频电场 标准场法 校准 平行板 不确定度
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基于平行板波导的紧凑化微波喷流设计
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作者 刘金玥 尚玉平 廖成 《电子元件与材料》 CAS 北大核心 2024年第8期994-1001,共8页
针对传统微波喷流装置体积质量大与集成度差的问题,提出了一种集成于平行板波导的紧凑型设计。在50Ω同轴线激励下,平行板波导支持柱面波形式的TM_(0)模在其内部传播。为了在波导末端预设焦点使周围形成微波喷流,通过馈源和焦点之间的... 针对传统微波喷流装置体积质量大与集成度差的问题,提出了一种集成于平行板波导的紧凑型设计。在50Ω同轴线激励下,平行板波导支持柱面波形式的TM_(0)模在其内部传播。为了在波导末端预设焦点使周围形成微波喷流,通过馈源和焦点之间的射线路径差异分析,得到了各射线在焦点处同相叠加所需的相位补偿条件。进一步,设计了仅含单层介质衬底的透射型超表面单元,其几何尺寸变化可使10 GHz处的透射相位在2π范围内调节,以满足相位补偿条件。将不同尺寸的单元以一维阵列形式集成于平行板波导末端,产生了良好的微波喷流特性。此外,对位于喷流区域内的亚毫米级导电圆柱,分析了微波喷流引起的后向散射增强效应。全波仿真与实验结果之间的吻合验证了该设计的有效性,微波喷流的紧凑化设计可为细微物体的微波检测实际应用提供基础。 展开更多
关键词 微波喷流 平行板波导 超表面 后向散射 微波检测
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MEMS静电驱动微镜阵列的设计与工艺研究
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作者 胡钰玮 王俊铎 +3 位作者 单亚蒙 钱磊 于悦 沈文江 《传感器与微系统》 CSCD 北大核心 2024年第10期113-116,共4页
基于微机电系统(MEMS)工艺,设计并制作了一种应用于光通信领域的二维准静态驱动微镜阵列(MMA)。相比于梳齿驱动,平行板电容式静电微镜更易于形成高占空比的阵列排布,有利于作为光开关矩阵应用在全光交换中。通过设计弹性系数小的“竖蛇... 基于微机电系统(MEMS)工艺,设计并制作了一种应用于光通信领域的二维准静态驱动微镜阵列(MMA)。相比于梳齿驱动,平行板电容式静电微镜更易于形成高占空比的阵列排布,有利于作为光开关矩阵应用在全光交换中。通过设计弹性系数小的“竖蛇形”双扭转轴结构,有效降低了微镜的驱动电压;并采用硅—玻璃阳极键合工艺来实现平板电容结构,将绝缘的玻璃作为电极基底与绝缘体上硅(SOI)硅器件层键合,不仅实现了良好的电隔离,提高了器件的稳定性,且能很好地与阵列扩展兼容。制备出的1×4微镜阵列可实现X/Y方向的二维(2D)准静态驱动,测试结果与有限元仿真结果基本吻合。结果表明,微镜内、外轴可分别在26.5V和29.5V的直流电压驱动下达到±2°机械转角,微镜响应时间为5ms。 展开更多
关键词 微机电系统 微镜阵列 平行板静电驱动 阳极键合
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基于聚酰亚胺的柔性湿度传感器制备及研究
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作者 张海力 谢光忠 +1 位作者 刘太君 代静 《仪表技术与传感器》 CSCD 北大核心 2024年第4期11-18,47,共9页
文中以聚酰胺酸(PAA)为前驱体,通过热处理工艺可得聚酰亚胺(PI)薄膜,添加氧化石墨烯(GO)合成PI/GO复合薄膜及后续电极制备得到基于聚酰亚胺的平行板电容式柔性湿度传感器。在此基础上深入研究了叉指电极式和平行板式构型、PAA旋涂转速、... 文中以聚酰胺酸(PAA)为前驱体,通过热处理工艺可得聚酰亚胺(PI)薄膜,添加氧化石墨烯(GO)合成PI/GO复合薄膜及后续电极制备得到基于聚酰亚胺的平行板电容式柔性湿度传感器。在此基础上深入研究了叉指电极式和平行板式构型、PAA旋涂转速、PAA酰亚胺化温度、GO喷涂量对湿度传感器性能的影响,最终得到的湿度传感器具有良好重复性、快速的响应恢复时间,最大湿滞仅为3.8%RH,且具有优异的柔性性能,在可穿戴柔性电子器件领域具有广泛的应用前景。 展开更多
关键词 柔性 湿度传感器 聚酰亚胺(PI) 氧化石墨烯(GO) PI/GO复合薄膜 平行板电容结构 湿敏特性
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基于Au/In键合的静电扭转微镜的设计与工艺研究
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作者 王俊铎 胡钰玮 +3 位作者 吴永强 单亚蒙 钱磊 沈文江 《固体电子学研究与进展》 CAS 2024年第3期252-257,共6页
采用Au/In键合技术并引入凸点层设计,制备了用于光通信领域的二维平行板式静电扭转微镜阵列。相较于其他键合技术,Au/In键合实现了低温键合并与硅通孔技术相容。此外,相对于梳齿驱动,采用平行板电容的扭转微镜有助于实现更高的占空比,... 采用Au/In键合技术并引入凸点层设计,制备了用于光通信领域的二维平行板式静电扭转微镜阵列。相较于其他键合技术,Au/In键合实现了低温键合并与硅通孔技术相容。此外,相对于梳齿驱动,采用平行板电容的扭转微镜有助于实现更高的占空比,便于阵列制造。凸点层的设计提升了键合强度,平均键合强度达8.97 MPa。微镜的实测结果与有限元仿真基本一致,内、外轴分别在13.7 V和18.2 V的直流电压下实现了0.7°的机械转角。 展开更多
关键词 微镜 Au/In键合 平行板静电驱动 微机电系统
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表面平齐的并联微穿孔板吸声结构特性仿真研究
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作者 张志成 刘俊林 +1 位作者 刘晗 崔展鹏 《振动与冲击》 EI CSCD 北大核心 2024年第15期228-234,共7页
针对火箭发动机燃气高温高速射流通道内噪声控制的工程需要,提出了一种表面平齐的并联微穿孔板吸声结构设计方案。基于微穿孔板吸声理论,建立了COMSOL微穿孔板吸声结构吸声性能仿真模型,对该类并联微穿孔板吸声结构的吸声特性进行了仿... 针对火箭发动机燃气高温高速射流通道内噪声控制的工程需要,提出了一种表面平齐的并联微穿孔板吸声结构设计方案。基于微穿孔板吸声理论,建立了COMSOL微穿孔板吸声结构吸声性能仿真模型,对该类并联微穿孔板吸声结构的吸声特性进行了仿真研究,分析了并联结构的背腔深度比、周期和单体宽度等多种参数对吸声性能的影响。结果表明,通过合理选择微穿孔板参数,以及并联共振腔深度、周期比、单体宽度等参数,可以得到吸声带宽、吸声系数较优的吸声结构,且加工制造与安装维护简单,研究成果可用于高温高速射流通道内的强噪声辐射环境控制。 展开更多
关键词 吸声性能 微穿孔板 并联结构 COMSOL仿真 共振腔 周期比
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工作面顶板导水两带发育高度动态监测研究
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作者 彭洪涛 章俊 +4 位作者 张二伟 杨彩 郝升明 段建东 陈洋洋 《煤》 2024年第10期6-9,83,共5页
随着我国煤矿开采深度、强度等的增加,采掘扰动极易诱发顶板水害事故。在矿井工作面回采过程中掌握煤层顶板导水两带发育规律,对煤层安全回采至关重要。文章以华北矿区某煤矿探查工作面顶板两带发育高度为目标,采用矿井并行电法动态监... 随着我国煤矿开采深度、强度等的增加,采掘扰动极易诱发顶板水害事故。在矿井工作面回采过程中掌握煤层顶板导水两带发育规律,对煤层安全回采至关重要。文章以华北矿区某煤矿探查工作面顶板两带发育高度为目标,采用矿井并行电法动态监测技术,通过在顶板钻孔内布设监测电极,实时动态获取回采过程中煤层顶板覆岩地电场动态演化规律,推断得到该工作面监测区域导水裂隙带发育高度为61 m,垮落带发育高度为17.4 m,有效指导了现场矿井水害防治工作。 展开更多
关键词 导水两带 动态监测 并行电法 工作面顶板
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金属盖板镀层形貌对平行缝焊器件抗盐雾性能的影响
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作者 马明阳 曹森 +2 位作者 杨振涛 张世平 欧彪 《电子与封装》 2024年第4期30-35,共6页
气密性封装是高可靠集成电路制造的关键技术。探讨了金属盖板表面镀层形貌对平行缝焊器件耐盐雾性能的影响。研究发现,平行缝焊后金属盖板表面出现的贯穿性裂纹是降低平行缝焊器件耐盐雾性能的关键因素。在相同封帽参数下,表面镀层为长... 气密性封装是高可靠集成电路制造的关键技术。探讨了金属盖板表面镀层形貌对平行缝焊器件耐盐雾性能的影响。研究发现,平行缝焊后金属盖板表面出现的贯穿性裂纹是降低平行缝焊器件耐盐雾性能的关键因素。在相同封帽参数下,表面镀层为长条形晶胞的盖板封帽后出现多条贯穿性裂纹,无法通过24 h盐雾试验后气密性检测。而表面镀层为均匀大小的圆形晶胞的盖板具备更高的抗封帽裂纹能力,封帽后无贯穿性裂纹出现,且可通过48 h盐雾试验后气密性检测。 展开更多
关键词 封装 平行缝焊 金属盖板 镀层形貌 盐雾试验 气密性检测
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锂电池模组液冷并联蛇形流道结构设计及优化
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作者 罗心源 金阳 《电力工程技术》 北大核心 2024年第5期160-169,188,共11页
锂离子电池被广泛应用于化学储能系统,然而由于该电池固有的产热特性,热失控成为了化学储能电站的一大安全隐患。因此优化设计电池热管理系统,有效避免热失控现象,对化学储能系统安全运行至关重要。文中设计了一种兼具串联折返与并联分... 锂离子电池被广泛应用于化学储能系统,然而由于该电池固有的产热特性,热失控成为了化学储能电站的一大安全隐患。因此优化设计电池热管理系统,有效避免热失控现象,对化学储能系统安全运行至关重要。文中设计了一种兼具串联折返与并联分支结构的新型并联蛇形流道液冷板,通过仿真实验,研究液冷板流道结构、液冷系统布置、冷却液入口流速对最高温度、温度分布均匀性、进出口压降的影响,以达到优化液冷系统的目的。结果表明,相同冷却液入口流速下,与传统并联流道相比,新型流道的最高温度降低0.2849 K、模组组内温差降低0.4663 K,与传统蛇形流道相比,其进出口压降减小40.18%;基于并联蛇形流道液冷板,液冷系统的最佳布置方案为冷却液二分口注入+液冷板交错布置;不同液冷板流速差异化设置,即两侧液冷板入口流速设定为0.1 m/s,居中液冷板入口流速设定为0.2 m/s,较四板保持相同流速为0.2 m/s的方案,电池模组组内温差降低13.62%,列间温差降低82.59%,能耗降低44.87%,达到“降本增效”的优化效果。合理的流道结构、交错的液冷板布置以及差异化的入口流速设计可以优化电池模组的液冷系统,增加电池模组运行的安全性。 展开更多
关键词 锂离子电池模组 热管理 液体冷却 并联蛇形液冷板 液冷板布置 差异化流速
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基于平行平板电极的非球面双液体透镜的仿真与实验分析 被引量:1
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作者 孔梅梅 董媛 +4 位作者 徐春生 刘悦 薛银燕 潘世成 赵瑞 《物理学报》 SCIE EI CAS CSCD 北大核心 2023年第24期171-178,共8页
应用介电泳原理,设计了一种基于平行平板电极的非球面双液体透镜,具有结构简单和易于实现的优点.利用Comsol,Matlab和Zemax软件,建立了相应的非球面双液体透镜光学模型,仿真分析了其在不同电压下的焦距变化及成像特性,并与球面双液体透... 应用介电泳原理,设计了一种基于平行平板电极的非球面双液体透镜,具有结构简单和易于实现的优点.利用Comsol,Matlab和Zemax软件,建立了相应的非球面双液体透镜光学模型,仿真分析了其在不同电压下的焦距变化及成像特性,并与球面双液体透镜模型进行了比较分析.非球面双液体透镜的变焦范围大于球面的,前者的成像质量亦优于后者.而且,实验制备了该非球面双液体透镜器件,结果表明,在工作电压为0—280 V时,焦距变化为54.2391—34.5855 mm,与仿真结果基本相符,而且该器件的成像分辨率最大可达45.255 lp/mm. 展开更多
关键词 介电泳原理 液体透镜 非球面 平行平板电极
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