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Micromixing in the Submerged Circulative Impinging Stream Reactor 被引量:20
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作者 伍沅 肖杨 周玉新 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第4期420-425,共6页
Micromixing in the submerged circulative impinging stream reactor (SCISR) developed by the authors is investigated with the Bourne's reaction scheme. The values measured for the impinging velocity, u0, under the ... Micromixing in the submerged circulative impinging stream reactor (SCISR) developed by the authors is investigated with the Bourne's reaction scheme. The values measured for the impinging velocity, u0, under the conditions of SCISR normal operation, only is of the order of 0.1m·s^-1, are much slower than that inferred,suggesting low power requirement for operation. The values of the characteristic time constant for micromixing,tM, determined in the impinging velocity range of 0.184m·s^-1 < u0 < 0.326m·s^-1 are ranged from 192ms to 87 ms, showing that impinging streams promotes micromixing very efficiently. The data follow approximately the relationship of tM∝ u0^-1.5. A comparative study shows that the micromixing performance of SCISR is much better than that of the traditional stirred tank reactor. The tM values predicted with the existing theoretical model are systematically longer than those measured by about 2--3 times, implying that the regularity of impinging streams promoting micromixing is unclear yet. 展开更多
关键词 MICROMIXING impinging streams REACTOR
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Optimal Conditions for Preparing Ultra-Fine CeO_2 Powders in A Submerged Circulative Impinging Stream Reactor 被引量:6
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作者 池汝安 徐志高 +1 位作者 吴元欣 王存文 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第4期422-427,共6页
Cerium carbonate powders were produced in a submerged circulation impinging stream reactor (SCISR) from Ce(NO3)3· 6H2O. NH4HCO3 was used as a precipitant in the reaction. Cerium carbonate powders were roasted... Cerium carbonate powders were produced in a submerged circulation impinging stream reactor (SCISR) from Ce(NO3)3· 6H2O. NH4HCO3 was used as a precipitant in the reaction. Cerium carbonate powders were roasted to produce ultra-fine cerium dioxide (CeO2) powders. The optimal conditions of such production process were obtained by orthogonal and one-factor experiments. The results showed that ultra-fine and narrowly distributed cerium carbonate powders were produced under the optimal flowing conditions. The concentrations of Ce(NO3)3 and NH4HCO3 solutions were 02,5 and 0.3 mol · L^-1, respectively. The concentration of PEG4000 added in these two solutions was 4 g · L^-1. The stirring ratio, reaction temperature, feeding time, solution pH, reaction time and digestion time were 900 r · min^- 1,80 ℃, 20 min, 5 - 6, 5 min and 1 h, respectively. The final product, CeO2 powders, was obtained by roasting the produced cerium carbonate in air for 3 h at 500 ℃. The finally produced CeO2 powders were torispherical particles with a narrow size distribution of 0.8 -2.5 μm. The crystal structure of CeO2 powders belonged to cubic crystal system and its space point 5 group was OH^5-FM3M. Under optimal conditions, powders produced by SCISR were finer and more narrowly distributed than that by Stirred Tank Reactor (STR). 展开更多
关键词 impinging stream REACTOR cerium dioxide ultra-fine powder rare earths
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Pressure Fluctuation in the Submerged Circulative Impinging Stream Reactor 被引量:14
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作者 孙怀宇 伍沅 徐成海 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第4期428-434,共7页
Pressure fluctuation in the submerged circulative impinging stream reactor (SCISR) is studied by measuring the dynamic pressure with micro pressure sensors of high accuracy, with water as the process material. Exper... Pressure fluctuation in the submerged circulative impinging stream reactor (SCISR) is studied by measuring the dynamic pressure with micro pressure sensors of high accuracy, with water as the process material. Experimental results show that the maximum amplitude of fluctuation can be up to about 1.6kPa. On the power spectra the fluctuation is relatively concentrated in the range of 〈1000Hz, with some weak peeks in acoustic wave range. The space profile of intensive fluctuation region in the reactor is determined. The region is found to take the form of a couple truncated cones of empty core, with coincided bottoms, and is symmetrical with respect to the impinging plane and approximately symmetrical about the axis, essentially independent of u0. The integral intensity of fluctuation increases as the impinging velocity, Uo increasing. 展开更多
关键词 pressure fluctuation impinging streams REACTOR
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Pressure Fluctuation in the Submerged Circulative Impinging Stream Reactor 被引量:2
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作者 孙怀宇 伍沅 徐成海 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第4X期428-434,共7页
Pressure fluctuation in the submerged circulative impinging stream reactor (SCISR) is studied by meas- uring the dynamic pressure with micro pressure sensors of high accuracy, with water as the process material. Ex- p... Pressure fluctuation in the submerged circulative impinging stream reactor (SCISR) is studied by meas- uring the dynamic pressure with micro pressure sensors of high accuracy, with water as the process material. Ex- perimental results show that the maximum amplitude of fluctuation can be up to about 1.6kPa. On the power spectra the fluctuation is relatively concentrated in the range of <1000Hz, with some weak peeks in acoustic wave range. The space profile of intensive fluctuation region in the reactor is determined. The region is found to take the form of a couple truncated cones of empty core, with coincided bottoms, and is symmetrical with respect to the impinging plane and approximately symmetrical about the axis, essentially independent of u0. The integral intensity of fluctua- tion increases as the impinging velocity, u0 increasing. 展开更多
关键词 PRESSURE FLUCTUATION impinging streamS REACTOR
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Theoretical analysis of fluid mixing time in liquid-continuous impinging streams reactor 被引量:3
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作者 罗燕 周剑秋 +2 位作者 郭钊 余蓓 熊卉 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期3217-3222,共6页
The mixing time of impact zone in liquid-continuous impinging streams reactor(LISR) is theoretically calculated by empirical model and modern micromixing model of the fluid mixing process, and the variation laws of ma... The mixing time of impact zone in liquid-continuous impinging streams reactor(LISR) is theoretically calculated by empirical model and modern micromixing model of the fluid mixing process, and the variation laws of macromixing time and micromixing time are quantitatively discussed. The results show that under a continuous and stable operating condition, as the paddle speed increases, the macromixing time and micromixing time calculated by the two models both decrease, even in a linkage equilibrium state. Simultaneously, as the paddle speed increases, the results figured by the two models tend to be consistent. It indicates that two models both are more suitable for calculation of mixing time in high paddle speed. Compared with the existing experimental results of this type of reactor, the mixing time computed in the speed of 1500 r/min is closer to it. These conclusions can provide an important reference for systematically studying the strengthening mechanism of LISR under continuous mixing conditions. 展开更多
关键词 impinging stream reactor empirical model theoretical model mixing time comparative analysis
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Experimental and Theoretical Analysis of the Impinging Stream Drying 被引量:2
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作者 淮秀兰 刘登瀛 SHIGERUKoyama 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第1期42-48,共7页
The experiments of one-stage semi-circular and two-stage semi-circular impinging stream drying as well as the vertical and semi-circular combined impinging stream drying were carried out. The velocity distribution and... The experiments of one-stage semi-circular and two-stage semi-circular impinging stream drying as well as the vertical and semi-circular combined impinging stream drying were carried out. The velocity distribution and the mean residence time of particles, and the influence of various factors on drying characteristics were studied. A mathematical model of granular material drying in a semi-circular impinging stream dryer was proposed, in which the flow characteristics as well as the heat and mass transfer mechanisms were considered. Reasonable numerical methods were used to solve the equations. Under various conditions, the calculated results agree well with the experimental data. The unsteady-state drying dynamic equation, as well as the variations of drying rate and moisture content versus time were obtained. The results indicate that constant drying rate period does not exist in a semi-circular impinging stream dryer. Appropriate semi-circular stage number and curvature radius, flow-rate ratio, air velocity, and higher inlet air temperature should be used for enhancing the drying process. 展开更多
关键词 impinging stream drying flow characteristics drying characteristics mathematical model
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RESISTANCE OF IMPINGING STREAM CONTACTOR TO SOLID-AIR SUSPENSION FLOW
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作者 吴高安 伍沅 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1997年第3期82-91,共10页
1 INTRODUCTIONAs mentioned in our previous paper impinging stream contactor(ISC)is aninnovative device for phase contact operations and has proved itself capable to en-hance transfer processes in heterogeneous systems... 1 INTRODUCTIONAs mentioned in our previous paper impinging stream contactor(ISC)is aninnovative device for phase contact operations and has proved itself capable to en-hance transfer processes in heterogeneous systems effectively,and thus is of poten-tial application in many chemical engineering processes,such as drying of solidparticles,solid-solid,liquid-liquid and gas-gas mixing,absorption and desorptionof gases into or from liquids with or without chemical reactions,combustion 展开更多
关键词 impinging streamS RESISTANCE pressure DROP CONTACTOR
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Experimental Investigation on Flow and Drying Characteristics of Impinging Stream Drying
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作者 Xiulan Huai, Dengying Liu, Xiaoming Cui, Qun Meng (Institute of Engineering Thermophysics, Chemise Academy of Sciences, P. O. Box 2706, Beijing 100080, China) 《Journal of University of Science and Technology Beijing》 CSCD 2001年第2期141-144,共4页
Based on the experimental investigation of one-stage semi-circular impinging stream drying, the experiments with the two-stage semi-circular, as well as the vertical and semi-circular combined impinging stream drying ... Based on the experimental investigation of one-stage semi-circular impinging stream drying, the experiments with the two-stage semi-circular, as well as the vertical and semi-circular combined impinging stream drying were conducted. The variations of system pressure drop, the mean residence time of particles with the mass flow-rate ratio and air velocity etc, were determined. The influences of inlet air temperature, mass flow-rate ratio, initial moisture content of particles and air velocity etc. on drying characteristics were also studied. The results indicate that the vertical and semi-circular combined impinging stream drying can make full use of the advantages of both the vertical and semi-circular impinging stream drying. Reasonable mass flow-rate ratio, air velocity, and higher inlet air temperature should be used for less energy consumption and cost during drying process. 展开更多
关键词 two-stage semi-circular impinging stream drying combined impinging stream drying flow characteristics drying characteristics
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Synthesis of Ce-doped yttrium aluminum garnet phosphor by impinging streams co-precipitation
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作者 李友凤 叶红齐 +2 位作者 何显达 韩凯 刘辉 《Journal of Central South University》 SCIE EI CAS 2012年第2期324-330,共7页
Phosphor yttrium aluminum garnet Y3A15O12 (YAG), activated with trivalent cerium (Ce^3+), was synthesized by T-tube impinging streams, T-type vortex impinging streams co-precipitation method (IS-CP) and direct ... Phosphor yttrium aluminum garnet Y3A15O12 (YAG), activated with trivalent cerium (Ce^3+), was synthesized by T-tube impinging streams, T-type vortex impinging streams co-precipitation method (IS-CP) and direct co-precipitation method (D-CP), respectively. The crystallization, morphologies, particle size and particle size distribution of the phosphors obtained under different experimental conditions were studied. The influence of various factors on the luminescence intensity of the phosphor was also investigated, such as feeding methods, volume flow rate, contents of Ce and initial reactant concentration. The results show that the precursors synthesized by T-tube impinging streams co-precipitation reaction transform to Y3A15O12 (YAG) phosphor at about 1 000 ℃. The particles are far smaller and narrower than those prepared by D-CP. In the impinging streams co-precipitation system, the luminescent intensity of YAG:Ce phosphor increases with the increase of liquid flow rate. The intensity firstly increases then decreases with the increasing Ce^3+ doping content, and the maximum intensity is shown at 1.67% (molar fraction) Ce. Luminescent intensity gradually decreases with the increase of initial concentration of reactants. At the same operational condition, the luminescent intensity of the phosphors prepared by T-tube impinging streams reactor is higher than that by D-CP, and the luminescent intensity of the phosphors prepared by T-type vortex impinging streams is higher than that by T-tube impinging streams reactor. 展开更多
关键词 yttrium aluminum garnet CE luminescent properties impinging streams CO-PRECIPITATION MICROMIXING
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基于振荡射流的撞击流反应器流动及混合特性研究
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作者 张建伟 刘名扬 +1 位作者 董鑫 冯颖 《流体机械》 CSCD 北大核心 2024年第5期47-54,共8页
为了研究振荡射流撞击流反应器内流场特性,利用SST k-ω湍流模型,建立振荡射流撞击流反应器数学模型且与试验进行对比。通过分析速度场、湍流动能分布、压力场和湍流黏度分布规律来研究撞击流反应器内部流动特性,揭示混合性能变化规律... 为了研究振荡射流撞击流反应器内流场特性,利用SST k-ω湍流模型,建立振荡射流撞击流反应器数学模型且与试验进行对比。通过分析速度场、湍流动能分布、压力场和湍流黏度分布规律来研究撞击流反应器内部流动特性,揭示混合性能变化规律。结果表明:在轴向上,速度、湍动能和压力呈多峰分布趋势且随着入口速度的上升而不断增大。在径向上,振荡器混合室内部涡旋中心受喷嘴小尺度涡旋干扰不断变化,从而影响流体振荡,使流场内产生4种流型。该反应器在35 s后混合均匀,混合强度达到0.95以上。研究结果丰富了流体振荡特性理论,为新型反应装置的开发提供理论参考。 展开更多
关键词 撞击流 振荡 流动特性 混合性能
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水平对置撞击流反应器强化液-液萃取及传质特性
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作者 张建伟 张昊明 +1 位作者 董鑫 冯颖 《高校化学工程学报》 EI CAS CSCD 北大核心 2024年第5期724-734,共11页
为了研究撞击流技术强化水相从煤油相中萃取乙酸,考察操作条件和溶液性质对萃取效果和传质特性的影响,测定液滴分散程度,利用响应面法优化萃取工况。结果表明:随煤油相进口体积流量和相比(水相与煤油相的体积流量比)的增加,分散相液滴... 为了研究撞击流技术强化水相从煤油相中萃取乙酸,考察操作条件和溶液性质对萃取效果和传质特性的影响,测定液滴分散程度,利用响应面法优化萃取工况。结果表明:随煤油相进口体积流量和相比(水相与煤油相的体积流量比)的增加,分散相液滴粒径分布范围先缩小后扩大,Sauter平均直径d32先减小后增大。萃取率和总体积传质系数随煤油相进口体积流量的增加、水相黏度的增加和表面张力的减小而先增大后减小,随相比的增加呈先增后减再增加的趋势。各因素对萃取率的影响程度为:相比>煤油相进口体积流量>十六烷基三甲基溴化铵(CTAB)质量浓度,且交互作用显著。最佳工况下萃取率为93.11%,较传统萃取工艺提高了5.11%。 展开更多
关键词 撞击流反应器 过程强化 萃取 传质 响应面分析
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双组分层撞击流反应器流场时空演化数值模拟
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作者 张建伟 刘名扬 +1 位作者 董鑫 冯颖 《高校化学工程学报》 EI CAS CSCD 北大核心 2024年第2期217-228,共12页
为了研究双组分层撞击流反应器流场时空演化规律,利用大涡模拟方法进行数值模拟。结合第三代涡识别方法在空间尺度上,对轴向面、周向环面和径向面的速度场、涡量场进行分析;在时间尺度上,揭示速度场、涡量场和涡当地旋转轴的演化规律。... 为了研究双组分层撞击流反应器流场时空演化规律,利用大涡模拟方法进行数值模拟。结合第三代涡识别方法在空间尺度上,对轴向面、周向环面和径向面的速度场、涡量场进行分析;在时间尺度上,揭示速度场、涡量场和涡当地旋转轴的演化规律。结果表明:轴向面和径向面的涡强度呈多峰分布,周向环面涡强度的变化分为增强-稳定-增强3阶段。以XOY面作为研究参考,在两层喷嘴间依据涡发生位置的变化和多尺度涡的碰撞、破碎情况,涡发生期分为6个阶段,涡演化周期分为12个阶段,可据此预测反应器内部流型变化和流场所处阶段。 展开更多
关键词 撞击流 湍流 流场 数值模拟 时空演化 流体力学
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基于场协同原理的涡发生器强化撞击流反应器混合性能分析
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作者 张建伟 尹祖彪 +1 位作者 董鑫 冯颖 《工程科学与技术》 EI CAS CSCD 北大核心 2024年第6期283-292,共10页
为了提高撞击流反应器的混合性能,采用数值模拟的方法分析了置入矩形翼涡发生器后撞击流反应器内的流场特性与混合特性,并且优化了矩形翼涡发生器参数。研究了矩形翼涡发生器尺寸参数与位置参数对撞击流反应器混合强度的影响,以及涡发... 为了提高撞击流反应器的混合性能,采用数值模拟的方法分析了置入矩形翼涡发生器后撞击流反应器内的流场特性与混合特性,并且优化了矩形翼涡发生器参数。研究了矩形翼涡发生器尺寸参数与位置参数对撞击流反应器混合强度的影响,以及涡发生器位置参数对反应器内速度分布和湍动能分布的影响,运用传质场协同原理分析了设置矩形翼涡发生器和未设置矩形翼涡发生器的撞击流反应器内速度场和浓度场的协同性。结果表明,随着径向间距r的增加混合强度呈现出先增后减的趋势,当翼宽h、转轴间距d和迎流攻角β逐渐增加时混合强度波动变化,在矩形翼涡发生器的翼宽h=10 mm,转轴间距d=8 mm,径向间距r=30 mm,迎流攻角β=30°时,反应器内混合强度最大,得到的混合效果最佳;在两股流体充分撞击的情况下,撞击流反应器内径向射流区域的速度分布呈现为“双峰”分布规律,涡发生器位置参数的改变可以提高径向速度,在转轴间距d=8 mm、迎流攻角β=30°时径向速度最高,反应器内径向射流区域的湍动能分布呈现出“单峰”分布规律,但涡发生器位置参数的变化对于湍动能分布的影响不大;从场协同的角度分析可知,矩形翼涡发生器的加入改变了撞击流反应器内径向射流的速度大小和方向,进而改善了撞击流反应器内速度场与浓度场的协同性,提高了撞击流反应器的混合性能。 展开更多
关键词 撞击流反应器 场协同理论 矩形翼涡发生器 数值模拟 混合强度
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超重力⁃水热法制备形貌可控的钛酸锶钡粉体
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作者 马瑶 袁志国 +4 位作者 李宇龙 付艺婷 张雅倩 贾正娜 孔哲 《中北大学学报(自然科学版)》 CAS 2024年第5期647-653,共7页
零维和多维结构的钛酸锶钡(Ba_(1-x)Sr_(x)TiO_(3),BST)粉体分别具有高比表面积和高长径比的优势,为提升材料性能并扩大电子元件中原材料的工业化应用,改善粉体制备过程中分布不均、耗时长的问题,采用撞击流-旋转填料床(IS-RPB)结合水... 零维和多维结构的钛酸锶钡(Ba_(1-x)Sr_(x)TiO_(3),BST)粉体分别具有高比表面积和高长径比的优势,为提升材料性能并扩大电子元件中原材料的工业化应用,改善粉体制备过程中分布不均、耗时长的问题,采用撞击流-旋转填料床(IS-RPB)结合水热法制备了添加丙三醇的BST粉体,考察了水热温度、水热时间及丙三醇添加量等因素对BST粉体形貌的影响规律。结合X-射线衍射仪(XRD)、扫描电子显微镜(SEM)以及透射电子显微镜(TEM)对BST粉体的形貌、晶相及组成进行了表征分析。结果表明:在超重力因子为40、撞击初速度10.61m/s、水热温度180℃、水热时间12h的条件下,当添加少量丙三醇时,其充当分散剂的作用,所制得的BST粉体为均匀性与分散性良好的纳米球形颗粒;当添加较多丙三醇时,其充当溶剂的作用,在水热条件下沿单元晶面生长得到了片状及花状形貌。本文提出的超重力-水热法及丙三醇的添加对于工业化形貌可控制备BST粉体探索提供了一种方便快捷的途径。 展开更多
关键词 水热法 撞击流-旋转填料床 钛酸锶钡 丙三醇 形貌调控
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不同动量比撞击流反应器流场特性数值模拟
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作者 张建伟 安丰元 +3 位作者 董鑫 冯颖 周春云 施博文 《沈阳化工大学学报》 CAS 2023年第1期49-55,共7页
目前撞击流技术在化学工程及多种过程工业中具有广泛应用.为了对撞击流混合器内的流动特征进行更深入地研究,利用数值模拟对撞击流混合器内流场特性进行分析.通过模拟得到不同动量比及不同喷嘴间距下撞击流反应器内流体速度、湍动能及... 目前撞击流技术在化学工程及多种过程工业中具有广泛应用.为了对撞击流混合器内的流动特征进行更深入地研究,利用数值模拟对撞击流混合器内流场特性进行分析.通过模拟得到不同动量比及不同喷嘴间距下撞击流反应器内流体速度、湍动能及压力分布,探究不同入口动量比对撞击流混合器流场特性的影响.结果表明:在xOy截面上两喷嘴的动量比越大,流体压力值越大,压力梯度分布越大;湍动能分布沿径向逐渐减小.对撞击面径向流体速度和压力进行分析,研究发现:当喷嘴间距L=2 D时,径向流体速度呈双峰分布,流体压力呈单峰分布;随着动量比的增加,流体的速度和压力整体增大.当L=4 D时,非等动量撞击下径向流体速度呈单峰分布;等动量撞击(K=1.0)下,撞击面径向上流体速度呈双峰分布;非等动量撞击的压力水平均低于等动量撞击. 展开更多
关键词 撞击流 数值模拟 流场特性 动量比
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撞击流—水力空化制备壳聚糖/蒙脱土复合材料及其应用 被引量:1
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作者 王宁 黄承都 +1 位作者 庞溪 黄永春 《食品与机械》 CSCD 北大核心 2023年第11期110-115,共6页
目的:解决传统机械搅拌制备壳聚糖/蒙脱土复合材料耗时长且不利于放大生产的问题。方法:利用撞击流—水力空化的方法制备壳聚糖/蒙脱土复合材料,考察了壳聚糖用量、壳聚糖相对分子质量、反应时间和反应温度4个因素对复合材料有机烧失率... 目的:解决传统机械搅拌制备壳聚糖/蒙脱土复合材料耗时长且不利于放大生产的问题。方法:利用撞击流—水力空化的方法制备壳聚糖/蒙脱土复合材料,考察了壳聚糖用量、壳聚糖相对分子质量、反应时间和反应温度4个因素对复合材料有机烧失率的影响,进而采用L_(9)(3^(4))正交试验优化制备材料的最佳方法。通过红外光谱、X射线衍射、扫描电镜、比表面分析仪对复合材料进行结构表征。结果:制备壳聚糖/蒙脱土复合材料的最优方案为:壳聚糖用量25 g、壳聚糖相对分子质量150万、空化时间20 min、空化反应温度80℃。在此条件下制备的复合材料的有机烧失率为37.42%,表征结果证明壳聚糖已成功负载到蒙脱土上,且复合材料依然具有蒙脱土的多孔结构。结论:撞击流—水力空化法与传统机械搅拌方法制备的复合材料相比,结构更疏松,比表面更大,有机烧失率、蔗汁脱色率更高,且撞击流—水力空化制备法更节省时间。 展开更多
关键词 壳聚糖 蒙脱土 撞击流 水力空化 有机烧失率 甘蔗汁澄清
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超重力共沉淀法制备纳米钛酸钡的研究 被引量:1
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作者 梁雅璐 袁志国 +1 位作者 马瑶 李宇龙 《中北大学学报(自然科学版)》 CAS 2023年第3期272-278,285,共8页
针对工业制备BaTiO_(3)粉体存在粒度分布不均、粒径大等难题,采用撞击流-旋转填料床(IS-RPB)反应器共沉淀法制备Sm^(3+)掺杂BaTiO_(3)纳米颗粒。考察了超重力因子、撞击初速度、掺杂浓度等因素对纳米钛酸钡粒径和粒度分布的影响规律。结... 针对工业制备BaTiO_(3)粉体存在粒度分布不均、粒径大等难题,采用撞击流-旋转填料床(IS-RPB)反应器共沉淀法制备Sm^(3+)掺杂BaTiO_(3)纳米颗粒。考察了超重力因子、撞击初速度、掺杂浓度等因素对纳米钛酸钡粒径和粒度分布的影响规律。结合X-射线衍射仪(XRD)、扫描电子显微镜(SEM)、红外光谱仪(FT-IR)、同步热分析仪(TG-DSC)以及纳米粒度分析仪对产物形貌、粒径等进行了表征分析。研究结果表明:IS-RPB反应器制备得到的BaTiO_(3)纳米颗粒粒径小且粒度分布均匀,高温煅烧后呈现四方相;在撞击初速度21.24 m/s、超重力因子45、掺杂浓度0.3%、煅烧温度950℃、保温时间2 h时,其粒径最小,为65 nm;陶瓷体在烧结温度1150℃、烧结时间2 h时密度为6.4 g/cm^(3),有利于提高其介电性能和陶瓷的稳定性。本文提出的超重力共沉淀法制备纳米钛酸钡是一种可在工业上拓展的制备方法。 展开更多
关键词 共沉淀法 撞击流-旋转填料床 纳米钛酸钡 掺杂 粒度分布
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撞击流反应器制备超细磷酸锌的工艺研究
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作者 袁雪松 张林锋 +2 位作者 吴华东 郭嘉 张烬 《武汉工程大学学报》 CAS 2023年第3期262-265,271,共5页
在撞击流反应器中,以氧化锌和磷酸为原料,乙醇-水溶液为溶剂,十六烷基三甲基溴化胺为分散剂,制备了超细磷酸锌产品。分别考察了反应物浓度、反应温度、反应时间、反应器搅拌转速及分散剂的用量对产品粒径的影响,并采用XRD、SEM和激光粒... 在撞击流反应器中,以氧化锌和磷酸为原料,乙醇-水溶液为溶剂,十六烷基三甲基溴化胺为分散剂,制备了超细磷酸锌产品。分别考察了反应物浓度、反应温度、反应时间、反应器搅拌转速及分散剂的用量对产品粒径的影响,并采用XRD、SEM和激光粒度分布仪对产物进行表征。结果表明制备磷酸锌的最佳工艺条件为:反应物浓度0.86 mol/L、反应温度70℃、反应时间1 h、反应器搅拌转速2400 r/min、分散剂用量1.0%(相对产品理论产量的质量分数)。在该条件下制备的产品的平均粒径为7.094μm,粒径集中分布在3~15μm之间。产品的粒径小且分布均匀,晶体微观形貌呈现出规则的薄片状。 展开更多
关键词 撞击流反应 磷酸锌 超细粉体
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撞击流反应-沉淀法制备氢氧化镁超细粉体
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作者 张忠闯 冯颖 +2 位作者 董鑫 闫宇航 张建伟 《辽宁化工》 CAS 2023年第9期1241-1243,1248,共4页
以六水合氯化镁和氢氧化钠为原料,利用撞击流反应器采用反应-沉淀法制备超细氢氧化镁粉体。采用单因素分析方法考察了镁离子浓度、进料流量、循环撞击时间、温度和搅拌时间等对粉体平均粒径的影响。结果表明:物料浓度和进料流量以及循... 以六水合氯化镁和氢氧化钠为原料,利用撞击流反应器采用反应-沉淀法制备超细氢氧化镁粉体。采用单因素分析方法考察了镁离子浓度、进料流量、循环撞击时间、温度和搅拌时间等对粉体平均粒径的影响。结果表明:物料浓度和进料流量以及循环撞击时间对氢氧化镁粉体平均粒径影响较大,在氯化镁浓度为0.75 mol·L^(-1)、进料流量为300 L·h^(-1)、循环撞击时间为60 min的最优条件下,制得的超细氢氧化镁粉体粒径分布均匀,其平均粒径为1.152μm。 展开更多
关键词 撞击流 反应沉淀法 氢氧化镁 超细粉体 结晶
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Characterization of micro-mixing in a novel impinging streams reactor 被引量:4
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作者 Hui HU Zhiming CHEN Zhen JIAO 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2009年第1期58-64,共7页
This paper presents an experimental investiga-tion of a novel impinging stream reactor(ISR)with the aim of high mixing intensity.The integral mixing quality in the reactor was measured with the iodide-iodate reaction ... This paper presents an experimental investiga-tion of a novel impinging stream reactor(ISR)with the aim of high mixing intensity.The integral mixing quality in the reactor was measured with the iodide-iodate reaction and showed excellent mixing performance.The impact of the operating parameters,such asfluxes,circulation and inter-nozzle distances,was investigated in terms of segregation index.The results showed that the increase offlux,the decrease of inter-nozzle distance and a suitable circulation can improve the micro-mixing efficiency.Based on turbulence theory,it was estimated that the characteristic micro-mixing time was 0.002–0.02 s,which was much shorter than that in the stirred tank reactor.The micro-mixing time was related to the segregation index,which was in good agreement with those in the literature. 展开更多
关键词 MICRO-MIXING impinging streams reactor turbulent mixing mass transfer
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