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1.
用NO2氧化二甲基硫醚(DMS)是合成二甲基亚砜(DMSO)的主要方法,反应过程受气液相传质影响很大.采用反应体积为120mL的连续搅拌釜式反应器,对该反应的宏观动力学进行了研究.在温度为30-60℃、NO2和DMS进料流量分别为0.01-0.10mol/min和0.005—0.05mol/min的范围内,考查了反应速率的变化,并测定了不同温度下NO2在DMSO中的饱和浓度.在热力学和动力学分析的基础上,推导出反应宏观动力学模型,由实验数据拟合出模型中的各参数.结果表明,该反应的活化能为21.64kJ/mol,液相组成变化时反应速率存在极大值,且模型计算值与实验值相吻合.  相似文献   

2.
在活性艳红X-3B光催化反应条件研究以及对浅池型固定床光催化反应器结构和操作参数考察的基础上,提出了反应器转化率的模型假设,并建立了转化率的数学模型.模型检验结果表明,转化率的数学模型计算值与实验测定值吻合情况较好.  相似文献   

3.
制备纳米Fe2O3的微乳体系研究   总被引:1,自引:0,他引:1  
通过测定不同油水比的电导率变化,研究了甲苯(MB)/十二烷基硫酸钠(SDS)/正丁醇(1-B),三氯化铁溶液(FeCl3)微乳体系的形成及影响体系稳定性的因素。实验表明:当MB和H2O总质量一定.SDS质量不变,正丁醇/甲苯=0.3时,水油体积比(Vw/Vo)小于0.6形成油包水(W/O)型微乳液,当Vw/Vo在1.3附近形成水包油(O/W)型微乳液。表面活性剂的种类,pH值,盐值影响微乳体系的稳定性。  相似文献   

4.
以对氨基苯乙烯硫酸酯(对位酯)与1-氨基-8-羟基-萘-3,6二磺酸(H酸)为对象,研究了它们间的酸性偶合反应过程,并对之加以反应动力学的处理。结果表明:1)该反应在动力学上是一个二级反应。当PH=3.25时,反应活化能为9.29kJ.15度时,反应半衰期为0.541min.2)当PH<3.25时,温度在5-15度时,反应产物单一。给出了PH和温度影响酸性偶合反应速度常数的关系式。  相似文献   

5.
在Pt/Al2O3催化剂上,用外循环无梯度反应器研究了异丁醇内扩散对异丁醇完全氧化动力学的影响。用0.45~0.60mm催化剂,反应在动力学区域进行,异丁醇完全氧化的动力学用-0.6级速度方程描述。当催化剂颗粒增大到4mm时,反应受内扩散控制,在内扩散区域异丁醇反应级数变为-0.01级。测定了催化剂有效因子η,其值在0.21~0.61之间。它表明孔扩散阻力严重。在温度恒定时,ηexp值随异丁醇分压的升高而增加。在异丁醇分压固定时,ηexp值随反应温度升高而下降。反应在动力学区域时,异丁醇完全氧化的活化能为26.0kJ/mol,而在内扩散区域时,反应活化能为23.7kJ/mol。  相似文献   

6.
利用常压微型固定床反应器,采用CuZnZrA lO甲醇重整制氢催化剂,考察了503~543K下甲醇停留时间(W/FA0)对CO2和CO转化率的影响,在排除内外扩散影响的条件下,采用甲醇直接重整和甲醇分解平行进行的反应途径,以CO和CO2为关键组分,建立了适合其在甲醇蒸汽重整制氢反应中使用的动力学模型,并利用最小二乘法确定了模型参数.F-检验表明所提出的动力学模型可作为反应器模拟分析和设计的基础.  相似文献   

7.
以偶氮二异丁腈为引发剂,在H2O/N,N’-二甲基甲酰胺(DMF)混合溶剂中成功实现了丙烯腈(AN)和2-乙烯基吡啶(EPD)的共聚反应,研究了共聚反应动力学规律和AN/EPD共聚物的热解反应动力学规律,得到了共聚反应动力学方程和AN/EPD共聚物热解反应表观活化能.当H2O/DMF(重量比)=100/0时,共聚反应动力学方程为R∝[AIBN]^0.695[AN]^1.89[EPD]^1.41,AN/EPD共聚物热解反应表观活化能为84.8kJ/mol;当H2O/DMF(重量比)=0/100时,共聚反应动力学方程为R∝[AIBN]^0.542[AN]^1.15[EPD]^1.02,AN/EPD共聚物热解反应表观活化能为138.6kJ/mol.在H2O含量较多的反应体系中,共聚反应机理倾向于悬浮聚合;而在含DMF较多的反应体系中,共聚反应机理倾向于溶液聚合.随着EPD含量的增加,AN/EPD共聚物热解反应表观活化能降低,但当EPD/AN(摩尔比)超过3/100后,共聚物热解反应表观活化能变化不明显,当聚合反应条件为CAN=5.0mol/L,CAIBN=0.006mol/L,CPVA=0.20g/L,H2O/DMF(重量比)=100/0,T=60℃,t=18min,EPD/AN(摩尔比)=5/100时,合成得到的AN/EPD共聚物热解反应表观活化能为72.9kJ/mol.  相似文献   

8.
微波辅助催化氧化高浓度含醛废水应用研究   总被引:18,自引:0,他引:18  
考查了活性炭(GAC)固定床反应器在微波辅助催化氧化作用下对某石化公司高浓度含醛废水的连续处理情况,在消除活性炭吸附作用后,在微波功率400W、废水流量6.0mL/min、空气流量0.085m^3/h和45gGAC条件下对含醛废水(初始CODCr浓度为33494mg/L)进行了处理.实验结果表明,含醛废水的CODCr去除率为94%,TOC去除率为99%;在没有GAC的条件下,微波对含醛废水则几乎没有效果.  相似文献   

9.
以用造纸黑液制成的球形木质素树脂作为生物载体,在上流式厌氧流化床(UAFB)反应器装置中,进行了处理模拟高浓度酸化相出水的厌氧甲烷相流化床的运行实验.结果表明,当有机容积负荷小于6.0g/(L·d)时,基质COD去除率高于90%;实验中得到生物负载量为0.0745;建立了UAFB反应器的动力学模型,测定了35℃时的动力学参数.  相似文献   

10.
在Pt/aL2o3催化剂上,用外循环无梯度反应器研究了异丁醇内扩散对异丁醇完全氧化动力学的影响。用0.45 ̄0.60mm催化剂,反应在动力学区域进行,异丁醇完全氧化的动力学用-0.6级速度方程描述。当催化剂颗粒增大到4mm时,反应受内扩散控制,在内扩散区域异丁醇反应级数变为-0.01级。测定了催化剂有效因子η,其值在0.21 ̄0.61之间。它表明孔扩散阻力严重。在温度恒定时,ηexp值随异丁醇分压  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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