期刊文献+
共找到304篇文章
< 1 2 16 >
每页显示 20 50 100
Procedure for determining the number of thermal diffusion columns in square cascade for separation of Ne stable isotopes
1
作者 Fatemeh Mansourzadeh Mohammad Mahdi Shadman +1 位作者 Javad Karimi Sabet Valiyollah Ghazanfari 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第5期47-55,共9页
The thermal diffusion column represents one method of separating stable isotopes.This method is advantageous for smallscale operations because of the simplicity of the apparatus and small inventory,especially in gas-p... The thermal diffusion column represents one method of separating stable isotopes.This method is advantageous for smallscale operations because of the simplicity of the apparatus and small inventory,especially in gas-phase operations.Consequently,it has attracted attention for its applicability in tritium and noble gas separation systems.In this study,the R cascade was used to design and determine the number of columns.A square cascade was adopted for the final design because of its flexibility,and calculations were performed to separate 20Ne and 22Ne isotopes.All the R cascades that enriched the Ne isotopes by more than 99%were investigated,the number of columns was determined,and the square cascade parameters were optimized using the specified columns.Additionally,a calculation code“RSQ_CASCADE”was developed.A unit separation factor of three was considered,and the number of studied stages ranged from 10 to 20.The results showed that the column separation power,relative total flow rate,and required number of columns were linearly related to the number of stages.The separation power and relative total flow decreased and the number of columns increased as the stage number increased.Therefore,a cascade of 85 columns is recommended to separate the stable Ne isotopes.These calculations yielded a 17-stage square cascade with five columns in each stage.By changing the stage cut,feed point,and cascade feed flow rate,the best parameters for the square cascade were determined according to the cascade and column separation powers.As the column separation power had a maximum value in cascade feed 50,it was selected for separating Ne isotopes. 展开更多
关键词 Stable isotope Thermal diffusion CASCADE separATION NEON
下载PDF
Structural Optimization of a Novel Up-run Gas-solid Separator
2
作者 Gai Xikun1 Tian Yuanyu2 +2 位作者 Xia Daohong1 Qiao Yingyun2(1.China University of Petroleum(East China),Qingdao 266555 2.Shandong University of Science and Technology,Qingdao 266510) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2011年第2期36-42,共7页
A new gas-solid separator dedicated to heavy-oil fast pyrolysis process incorporating inertial and centrifugal separation was designed. Gas and typical fluid catalytic cracking (FCC) catalyst particles (with a dens... A new gas-solid separator dedicated to heavy-oil fast pyrolysis process incorporating inertial and centrifugal separation was designed. Gas and typical fluid catalytic cracking (FCC) catalyst particles (with a density of 1500 kg/m3, and a mean diameter of 45.81 p.m) were used in the study. The inlet gas velocity was kept constant at 13.36 m/s, while the solid loading at the inlet ranged from 0 to 700 g/m3. When the exhaust pipe opening was provided with two narrow-width slots near the inlet without baffles, the solid collection efficiency increased with an increasing solid loading at the inlet and was close to 95% along with a decreasing pressure drop. After increasing the secondary separation structure, the separation efficiency greatly improved. By adjusting the diameter of the secondary exhaust pipe, the separation efficiency and pressure drop could be balanced. Under the experimental conditions, when the diameter of the second exhaust pipe was equal to d=100 mm, the pressure drop was lower than 1400 Pa while the separation efficiency could exceed 99.50%; and when the diameter was equal to d=120 mm, the pressure drop was less than 700 Pa, with the separation efficiency reaching over 99.00%. 展开更多
关键词 gas-solid separation separation efficiency pressure drop cyclone separators
下载PDF
Effects of the inlet particle spatial distribution on the performance of a gas-solid cyclone separator
3
作者 Yuge Yao Manxia Shang +3 位作者 Xiwei Ke Zhong Huang Tuo Zhou Junfu Lyu 《Particuology》 SCIE EI CAS CSCD 2024年第2期133-145,共13页
The present study was aimed at the inlet particle spatial distribution of a gas-solid separator with high solid loading and investigated its effects on cyclone performance and the inner flow pattern.The flow fields of... The present study was aimed at the inlet particle spatial distribution of a gas-solid separator with high solid loading and investigated its effects on cyclone performance and the inner flow pattern.The flow fields of a cyclone with different rectangular particle flow areas on the inlet surface were numerically simulated using a four-way coupling method.The simulated results indicate that reducing the inlet particle flow area and lowing the inlet particle position can effectively reduce the scattered particles inside the cyclone separator and enhance the separation performance.Vertically gathering the particles to the centerline can also weaken the particle back-mixing.The particles near the roof account for the swirling particle ceiling phenomenon.The inlet particle spatial distribution affects the pressure drop mainly by affecting the gas tangential velocity in the cylinder body.Moreover,compared to the hori-zontal particle distribution on the inlet surface,the vertical particle distribution has greater effects on cyclone performance. 展开更多
关键词 gas-solid cyclone Inlet particle spatial distribution Four-way coupling separation efficiency Scattered particle
原文传递
Functional Separable Solutions to Nonlinear Diffusion Equations by Group Foliation Method 被引量:5
4
作者 HU Jia-Yi QU Chang-Zheng YIN Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期193-199,共7页
We consider the functional separation of variables to the nonlinear diffusion equation with source and convection term: ut = (A(x)D(u)ux)x + B(x)Q(u), Ax ≠ 0. The functional separation of variables to thi... We consider the functional separation of variables to the nonlinear diffusion equation with source and convection term: ut = (A(x)D(u)ux)x + B(x)Q(u), Ax ≠ 0. The functional separation of variables to this equation is studied by using the group foliation method. A classification is carried out for the equations which admit the function separable solutions. As a consequence, some solutions to the resulting equations are obtained. 展开更多
关键词 group foliation method functional separation of variable nonlinear diffusion equation symmetry group
下载PDF
New variable separation solutions for the generalized nonlinear diffusion equations 被引量:1
5
作者 吉飞宇 张顺利 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第3期45-51,共7页
The functionally generalized variable separation of the generalized nonlinear diffusion equations ut = A(u, Ux)Uxx + B(u, ux) is studied by using the conditional Lie-Blicklund symmetry method. The variant forms o... The functionally generalized variable separation of the generalized nonlinear diffusion equations ut = A(u, Ux)Uxx + B(u, ux) is studied by using the conditional Lie-Blicklund symmetry method. The variant forms of the considered equations, which admit the corresponding conditional Lie--Biicklund symmetries, are characterized. To construct functionally gener- alized separable solutions, several concrete examples defined on the exponential and trigonometric invariant subspaces are provided. 展开更多
关键词 conditional Lie-Buicklund symmetry functionally generalized separable solution generalizednonlinear diffusion equation invariant subspace
下载PDF
Phase separation and super diffusion of binary mixtures of active and passive particles 被引量:1
6
作者 Yan Wang Zhuanglin Shen +2 位作者 Yiqi Xia Guoqiang Feng Wende Tian 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第5期26-31,共6页
Computer simulations were performed to study the dense mixtures of passive particles and active particles in two dimensions.Two systems with different kinds of passive particles(e.g.,spherical particles and rod-like p... Computer simulations were performed to study the dense mixtures of passive particles and active particles in two dimensions.Two systems with different kinds of passive particles(e.g.,spherical particles and rod-like particles)were considered.At small active forces,the high-density and low-density regions emerge in both systems,indicating a phase separation.At higher active forces,the systems return to a homogeneous state with large fluctuation of particle area in contrast with the thermo-equilibrium state.Structurally,the rod-like particles accumulate loosely due to the shape anisotropy compared with the spherical particles at the high-density region.Moreover,there exists a positive correlation between Voronoi area and velocity of the particles.Additionally,a small number of active particles capably give rise to super-diffusion of passive particles in both systems when the self-propelled force is turned on. 展开更多
关键词 phase separation super diffusion active particles binary mixtures
下载PDF
Numerical study of n-heptane/benzene separation by thermal diffusion column
7
作者 Neda Hashemipour Javad Karimi-Sabet +3 位作者 Kazem Motahari Saeed Mahruz Monfared Younes Amini Mohammad Ali Moosavian 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第8期1745-1755,共11页
In this article,numerical simulations are performed to investigate the performance of the thermal diffusion column for the separation of n-heptane/benzene mixture.The present work tried to optimize column by analyzing... In this article,numerical simulations are performed to investigate the performance of the thermal diffusion column for the separation of n-heptane/benzene mixture.The present work tried to optimize column by analyzing significant parameters such as feed flow rate,temperature and cut.In order to obtain the hydrodynamic and temperature and mass distribution inside thermal diffusion column,computational fluid dynamic(CFD) method is applied to solve the Navier-Stocks equations.Numerical simulations are conducted to study the main parameters in both stationary and time-dependent conditions.By using the separation work unit as a function of cut,the optimal cut for maximum SWU occurs within a limited range of 0.47-0.5 for feed rate between 0.5 and 4 g min^-1.Our findings reveal that the optimum feed rate in the range of optimum cut is about 1 g min^-1.In transient study,results show that the best cut for reaching to steady-state condition is θ=0.5. 展开更多
关键词 Thermal diffusion column(TDC) Computational fluid dynamic separative work unit n-Heptane/benzene separATION
下载PDF
TURBULENT SEPARATED REATTACHED FLOW IN A TWO-DIMENSIONAL CURVED-WALL DIFFUSER
8
作者 尹军飞 余少志 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1993年第2期117-123,共7页
A turbulent separation-rcattachment flow in a two-dimensional asymmetrical curved-wall diffuser is studied by a two-dimensional laser doppler velocimeter.The turbulent boundary layer separates on the lower curved wall... A turbulent separation-rcattachment flow in a two-dimensional asymmetrical curved-wall diffuser is studied by a two-dimensional laser doppler velocimeter.The turbulent boundary layer separates on the lower curved wall under strong pressure gradient and then reattaches on a parallel channel.At the inlet of the diffuser,Reynolds number based on the diffuser height is 1.2×10~5 and the velocity is 25.2m/s.The re- sults of experiments are presented and analyzed in new defined streamline-aligned coordinates.The experiment shows that after Transitory Detachment Reynolds shear stress is negative in the near-wall backflow region. Their characteristics are approximately the same as in simple turbulent shear layers near the maximum Reynolds shear stress.A scale is formed using the maximum Reynolds shear stresses.It is found that a Reynolds shear stress similarity exists from separation to reattachment and the Schofield-Perry velocity law ex- ists in the forward shear flow.Both profiles are used in the experimental work that leads to the design of a new eddy-viscosity model.The length scale is taken from that developed by Schofield and Perry.The composite velocity scale is formed by the maximum Reynolds shear stress and the Schofield Perry velocity scale as well as the edge velocity of the boundary layer.The results of these experiments are presented in this paper 展开更多
关键词 separating flow boundary layer turbulent flow turbulence model Laser Doppler Velocimeter two- dimensional diffuser
下载PDF
Structure Optimization of a Horizontal Gas-Solid Rapid Separation Device
9
作者 An Xiaoxi Fan Junfeng +2 位作者 Tian Yuanyu Qiao Yingyun Zong Peijie 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2020年第1期69-77,共9页
To meet the requirements for fast and efficient gas-solid separation at the outlet of a gas-solid concurrent downflow fluidized bed(downer),a new horizontal gas-solid rapid separator was designed based on the joint ac... To meet the requirements for fast and efficient gas-solid separation at the outlet of a gas-solid concurrent downflow fluidized bed(downer),a new horizontal gas-solid rapid separator was designed based on the joint action of centrifugal and inertial forces.Under the same experimental conditions,a fluid catalytic cracking(FCC)catalyst was used as the material(with a particle density of 1500 kg/m3 and a mean particle size of 45.8μm)to experimentally investigate the effects of the insertion length of gas outlet pipe,the bypass cylinder,the gas outlet direction,and the secondary separation structure on the separator performance.The results showed that with an inlet gas flow rate of 14.5 m/s and a gas phase solid content of 60―835 g/m3,the downer system achieved a gas-solid separation efficiency of above 99.5%,with the separator’s pressure drop within 1846 Pa(when the separator included a bypass cylinder and a secondary separation structure with a proper insertion length of gas outlet pipe). 展开更多
关键词 gas-solid separator BYPASS CYLINDER separation efficiency pressure DROP
下载PDF
Approximate derivative-dependent functional variable separation for quasi-linear diffusion equations with a weak source
10
作者 吉飞宇 杨春晓 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期67-72,共6页
By using the approximate derivative-dependent functional variable separation approach, we study the quasi-linear diffusion equations with a weak source ut = (A(u)Ux)x + eB(u, Ux). A complete classification of t... By using the approximate derivative-dependent functional variable separation approach, we study the quasi-linear diffusion equations with a weak source ut = (A(u)Ux)x + eB(u, Ux). A complete classification of these perturbed equations which admit approximate derivative-dependent functional separable solutions is listed. As a consequence, some approxi- mate solutions to the resulting perturbed equations are constructed via examples. 展开更多
关键词 quasi-linear diffusion equation approximate derivative-dependent functional separable solution approximate generalized conditional symmetry
下载PDF
储氚组件中氚依次渗透到相邻腔体的规律研究
11
作者 尹益辉 梁浩 范志庚 《绵阳师范学院学报》 2024年第2期1-9,共9页
考虑氚的时时和处处衰变,建立三腔体两隔片气路组件中隔片材料内部氚浓度控制方程,求解得到了渗透过隔片的瞬态氚量、中间腔体和右侧腔体中瞬态氚量和氚压力的高精度解析解.通过解析理论计算,认识了中间腔体和尾端腔体中瞬态氚压力随时... 考虑氚的时时和处处衰变,建立三腔体两隔片气路组件中隔片材料内部氚浓度控制方程,求解得到了渗透过隔片的瞬态氚量、中间腔体和右侧腔体中瞬态氚量和氚压力的高精度解析解.通过解析理论计算,认识了中间腔体和尾端腔体中瞬态氚压力随时间、储存温度和隔片厚度的变化规律,揭示出两个腔体中氚压力都具有最大单峰特性,且压力峰值出现时间几乎与隔片厚度无关等特性.研究结果为相关储氚装备的工程研制和使用提供了理论依据. 展开更多
关键词 储氚组件 隔片 氚扩散 氚渗透 瞬态氚压力
下载PDF
附面层吸入条件下非轴对称静子对风扇流场影响数值研究 被引量:2
12
作者 傅文广 王维佳 +2 位作者 孙鹏 王春雪 赵伟 《推进技术》 EI CAS CSCD 北大核心 2024年第3期160-171,共12页
附面层吸入导致进气道与风扇气动交界面处产生严重的总压、旋流畸变,进而使得风扇效率、稳定性降低,是制约其应用的主要问题之一。为了提高风扇的抗畸变能力,本文对风扇静子进行了非轴对称设计和数值仿真计算。结果表明:相较于原型风扇... 附面层吸入导致进气道与风扇气动交界面处产生严重的总压、旋流畸变,进而使得风扇效率、稳定性降低,是制约其应用的主要问题之一。为了提高风扇的抗畸变能力,本文对风扇静子进行了非轴对称设计和数值仿真计算。结果表明:相较于原型风扇,非轴对称静子效率提高0.31个百分点,失速裕度提高50.5%,风扇内部流场有明显改善,扩压因子减小,畸变区静叶叶尖吸力面角区分离范围显著降低,叶片通道通流能力上升。非轴对称静子改型方案通过改变畸变区静叶进口几何角与弦长,使静叶冲角基本不变,稠度增加,气流在吸力面上不易发生分离,从而使得角区分离范围减小,流动损失降低,风扇性能提升。 展开更多
关键词 附面层吸入 非轴对称静子 扩压因子 失速裕度 角区分离
下载PDF
定制电解液或隔膜实现锂离子各向异性输运从而抑制枝晶生长:相场模拟研究
13
作者 李亚捷 陈斌 +4 位作者 王依平 邢辉 赵伟 张更 施思齐 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第3期71-72,共2页
电池内部不可控的枝晶生长问题严重地影响着电池的循环性能和安全性能,这对于锂金属电池的实际应用是一个严峻的挑战。尽管已有较多的实验和理论研究工作聚焦于电极间锂离子各向异性输运特性对枝晶形貌的影响,但仍有一些开放性的问题有... 电池内部不可控的枝晶生长问题严重地影响着电池的循环性能和安全性能,这对于锂金属电池的实际应用是一个严峻的挑战。尽管已有较多的实验和理论研究工作聚焦于电极间锂离子各向异性输运特性对枝晶形貌的影响,但仍有一些开放性的问题有待进一步研究,例如,如何将枝晶生长的动态演变与电解液性质、电势分布或隔膜多孔结构诱导的锂离子各向异性输运关联起来。我们通过将锂离子在电解液中的扩散系数(D_(L))表示为二阶张量的形式并进行相场模拟,发现D_(yy):D_(xx)比值的增加,以及电势诱导的电极/电解液界面锂离子快速扩散层均可以降低界面处锂离子浓度梯度和电势梯度,从而减弱枝晶生长的驱动力。我们还发现隔膜基体与y方向之间夹角的增大也会显著促进电解质中的锂离子各向异性输运特性,以利于抑制枝晶生长。籍此本文提出设计D_(yy):D_(xx)=10:1的电解液和基体倾斜角为arctan(0.5)的隔膜用于锂金属电池。该相场研究有望为设计具有抑制枝晶能力的电解质或隔膜提供指导。 展开更多
关键词 锂枝晶 相场模拟 电解质 隔膜 锂离子扩散系数
下载PDF
分割RCHOP方案在老年初治弥漫性大B细胞淋巴瘤中的疗效与安全性分析
14
作者 陈子琪 李文琪 +4 位作者 孙金淼 常宇 柳喜洋 张明智 张蕾 《中国肿瘤临床》 CAS CSCD 北大核心 2024年第4期170-177,共8页
目的:探究分割利妥昔单抗(rituximab)+环磷酰胺(cyclophosphamide,CTX)+长春新碱(vincristine,VCR)+多柔比星(doxorubicin)+泼尼松(prednisone)的(RCHOP方案)治疗65~80岁初治弥漫性大B细胞淋巴瘤(diffuse large B-cell lymphoma,DLBCL)... 目的:探究分割利妥昔单抗(rituximab)+环磷酰胺(cyclophosphamide,CTX)+长春新碱(vincristine,VCR)+多柔比星(doxorubicin)+泼尼松(prednisone)的(RCHOP方案)治疗65~80岁初治弥漫性大B细胞淋巴瘤(diffuse large B-cell lymphoma,DLBCL)的疗效与安全性。方法:选取郑州大学第一附属医院2013年4月至2022年9月收治的137例65~80岁初治DLBCL患者,根据化疗方案的不同分为分割RCHOP组、足量RCHOP组和减量RCHOP样组3组。所有患者均以21天为1个周期,治疗4~8个周期。比较3组近期疗效、远期疗效和不良反应发生情况,分析患者无进展生存期(progressiom-free survival,PFS)及总生存期(overall survival,OS)的影响因素。结果:分割RCHOP组、足量RCHOP组和减量RCHOP样组的客观缓解率(overall respond rate,ORR)分别为89.7%、90.3%、86.1%,差异无统计学意义,分割RCHOP组的完全缓解率(complete respond rate,CRR)为64.1%高于减量RCHOP样组(33.3%),差异具有统计学意义(P=0.008),而与足量RCHOP组(66.1%)差别不大。生存曲线分析结果显示分割RCHOP组与足量RCHOP组的PFS和OS均无统计学差异。分割RCHOP组相比减量RCHOP样组改善了PFS(P=0.036),而两组的OS无统计学差异。多因素分析显示,国际预后指数(IPI)和分割RCHOP方案对DLBCL患者PFS均有显著性影响(均P<0.05),IPI评分对DLBCL患者OS具有显著性影响(P<0.001)。分割RCHOP组白细胞减少及3~4级白细胞减少的发生率低于足量RCHOP组,差异具有统计学意义(P=0.007、P=0.012),其余差异无统计学意义。结论:年龄在65~80岁的初治弥漫性大B细胞淋巴瘤患者中,分割RCHOP方案近期疗效、远期疗效及安全性、耐受性均良好。 展开更多
关键词 分割RCHOP 方案 初治弥漫性大B 细胞淋巴瘤 老年 疗效 安全性
下载PDF
以SiH_(4)为介质扩散法生产^(28)Si技术研究
15
作者 孙旺 周明胜 +1 位作者 姜东君 潘建雄 《同位素》 CAS 2024年第3期203-210,共8页
^(28)Si同位素主要应用于半导体领域,在量子计算、计量学领域也有一定应用。采用99%以上丰度^(28)Si制备硅晶体,可以降低声子散射、提高热导率,并且降低门电压、提高开关速度、提高芯片频率,可用于制造高速CPU、大功率器件、高性能传感... ^(28)Si同位素主要应用于半导体领域,在量子计算、计量学领域也有一定应用。采用99%以上丰度^(28)Si制备硅晶体,可以降低声子散射、提高热导率,并且降低门电压、提高开关速度、提高芯片频率,可用于制造高速CPU、大功率器件、高性能传感器等。在室温下,99.85%以上丰度^(28)Si半导体元件的热导率比天然丰度Si材料增加10%~60%。高丰度^(28)Si可用于制备量子信息长自旋相干时间器件,去除29Si干扰。本研究采用气体扩散法,以SiH_(4)为介质,开展^(28)Si同位素的分离研究。目前廉价优质的高分子有机膜已得到大规模工业应用。用于负压条件下的高速磁悬浮压缩机可以有效压缩SiH_(4)气体。通过4级扩散级联实验测得SiH_(4)的基本全分离系数可达1.010。采用多元分离理论进行级联分析计算,以天然SiH_(4)为原料,通过一次不超过300级的相对丰度匹配级联,可将轻馏分中的^(28)Si同位素丰度浓缩到99%以上。本研究验证了以SiH_(4)为介质扩散分离^(28)Si同位素可行。 展开更多
关键词 硅同位素 甲硅烷 气体扩散法 基本全分离系数
下载PDF
扩散噪声环境下的多通道盲语音分离方法
16
作者 刘升东 杨飞然 +2 位作者 王谋 李茁 杨军 《声学学报》 EI CAS CSCD 北大核心 2024年第6期1304-1314,共11页
适用于超定系统的处理扩散噪声的独立向量提取方法受限于高斯噪声假设,无法消除与目标声源同方向的扩散噪声。为此,提出了一种适用于扩散噪声环境的多通道盲源分离方法。该方法假设扩散噪声在各个方向上的能量分布均匀且具有时变特性。... 适用于超定系统的处理扩散噪声的独立向量提取方法受限于高斯噪声假设,无法消除与目标声源同方向的扩散噪声。为此,提出了一种适用于扩散噪声环境的多通道盲源分离方法。该方法假设扩散噪声在各个方向上的能量分布均匀且具有时变特性。采用低秩声源模型和秩1空间模型构建适用于扩散噪声环境下混合信号的概率模型。在此基础上,通过最大似然准则推导出分离矩阵的更新公式,并估计语音和噪声的功率谱密度。最后,利用维纳滤波抑制与目标声源相同方向的扩散噪声。仿真实验结果表明,所提方法的声源分离性能和抑制噪声能力比现有算法取得了显著提高,验证了其在复杂噪声环境下的有效性。 展开更多
关键词 盲源分离 非负矩阵分解 独立低秩矩阵分析 扩散噪声
下载PDF
荷电颗粒在旋转环形通道内分离性能研究
17
作者 沈家鑫 彭慧 +2 位作者 王彦入 尹招琴 包福兵 《计算力学学报》 CAS CSCD 北大核心 2024年第3期491-498,共8页
为研究带电旋转环形通道内荷电颗粒的运动和沉积特性,本文使用计算流体力学两相流离散颗粒法对带电旋转环形通道内的荷电颗粒的运动过程进行了模拟。根据模拟结果分析了不同粒径、电压、入口雷诺数和通道长径比等参数对荷电颗粒运动和... 为研究带电旋转环形通道内荷电颗粒的运动和沉积特性,本文使用计算流体力学两相流离散颗粒法对带电旋转环形通道内的荷电颗粒的运动过程进行了模拟。根据模拟结果分析了不同粒径、电压、入口雷诺数和通道长径比等参数对荷电颗粒运动和沉积的影响,研究了荷电颗粒在旋转通道内离心力与电场力之间的竞争关系,探索了离心力和电场力导致的荷电颗粒运动和沉积变化的规律。结果表明,单个不同粒径颗粒具有不同的颗粒逃逸电压区间,区间的大小随着颗粒粒径的增大而增大,且区间的宽度随着通道长径比的增大将会明显变小;多个颗粒的逃逸率曲线,不同粒径的颗粒将会有不同程度的交叉,随着长径比的增大,颗粒逃逸率曲线的高度与交叉会有明显的减小,而随着转速的增大,颗粒逃逸率曲线的交叉会有一定程度的减小,且高度不会有明显变化。 展开更多
关键词 荷电颗粒 旋转流场 环形通道 分离性能 扩散荷电
下载PDF
汽化溶剂在MOF材料扩散系数测定的装置设计与实现
18
作者 薛峰 王晟 居沈贵 《实验科学与技术》 2024年第1期127-130,160,共5页
测定汽化溶剂在固相吸附剂晶内扩散系数是重要的吸附参数,传统实验教学滞后于“解决复杂问题能力”的培养要求。该文以“气相扩散系数测定实验”为对象,将其拓展为“汽化溶剂在MOF(HKUST-1型)多孔材料晶内扩散系数测定实验装置设计与实... 测定汽化溶剂在固相吸附剂晶内扩散系数是重要的吸附参数,传统实验教学滞后于“解决复杂问题能力”的培养要求。该文以“气相扩散系数测定实验”为对象,将其拓展为“汽化溶剂在MOF(HKUST-1型)多孔材料晶内扩散系数测定实验装置设计与实现”,它结合气相色谱仪FID检测器原理和零长柱法测定晶内扩散系数的原理,提出实验设计方案、实验测量法和数据拟合法,并对零长柱法(ZLC)做了MATLAB软件模拟计算,拟合实验数据与文献报道值接近。该实验在学生操作过程中,实验系统由学生根据实验原理自助搭建,将实验原理、吸附材料装填、数据采集和测量、数据分析和报告撰写融为一体,践行新工科人才培养理念,提高人才培养目标的达成度。 展开更多
关键词 吸附分离 零长柱法 晶内扩散系数 MOF
下载PDF
国外后处理厂氪-85管理实践及其启示
19
作者 刘建权 曹龙浩 +2 位作者 赵学延 韦萌 任丽丽 《广东化工》 CAS 2024年第14期59-61,80,共4页
由于氪-85是后处理厂排放的放射性活度最高的同位素,且能造成全球较高的集体剂量,20世纪70年代起,以美国为代表的国家都对氪-85分离整备技术进行了科学探索和工程实践,发展出了以低温蒸馏为代表的技术路线,除在氪分离工艺、氪的长期贮... 由于氪-85是后处理厂排放的放射性活度最高的同位素,且能造成全球较高的集体剂量,20世纪70年代起,以美国为代表的国家都对氪-85分离整备技术进行了科学探索和工程实践,发展出了以低温蒸馏为代表的技术路线,除在氪分离工艺、氪的长期贮存中都遇到了安全问题。与此同时,由于氪-85放射性毒性低、对公众个人有效剂量的贡献很低、氪分离整备工程化存在一定安全问题且投资巨大,法国、英国的后处理厂将几乎全部的氪-85以气载流出物形式排放到环境中进行稀释扩散。另外,尽管氪-85是一种应用较为广泛的同位素,但其市场规模远小于后处理厂氪-85的年排放量。综上,建议我国参考法、英等国的氪-85管理实践选择稀释扩散方案对后处理厂氪-85进行管理。 展开更多
关键词 氪-85 后处理厂 管理方案 分离整备 稀释扩散
下载PDF
LNG储罐周边防火间距分析
20
作者 刘洋 杜帆 +2 位作者 郭敏 李皓玥 石双 《石油化工安全环保技术》 CAS 2024年第5期53-55,I0003,I0004,共5页
依据《石油天然气工程设计防火规范》(GB50183—2004)和《天然气液化工厂设计标准》(GB 51261—2019),采用国际公认的挪威船级社DNV PHAST火灾计算模型,对某液化天然气储存站场防火间距进行计算分析,在站场安全和社会经济的角度,探求适... 依据《石油天然气工程设计防火规范》(GB50183—2004)和《天然气液化工厂设计标准》(GB 51261—2019),采用国际公认的挪威船级社DNV PHAST火灾计算模型,对某液化天然气储存站场防火间距进行计算分析,在站场安全和社会经济的角度,探求适用于当地环境的液化天然气站场的防火间距,从而降低对周围建筑物的风险,为企业安全生产提供依据。 展开更多
关键词 LNG储罐 泄漏扩散 防火间距 热辐射影响距离 扩散隔离区边界
下载PDF
上一页 1 2 16 下一页 到第
使用帮助 返回顶部