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1.
酒精厂排出的废气CO2含量高、纯度大。据此研究了CO2与石灰乳在湍球吸收塔内进行不连续碳化反应和连续碳化反应;探讨了CO2的通气量,石灰乳浓度和流量、湍球的大小和填充量、塔的直径和塔板数对工艺的影响,获得了工业化生产的有关指标和数据。  相似文献   

2.
对碳化作用细观求解方法进行梳理改进,利用传输和反应过程状态变化的路径依赖特点,规避了传统方法大规模矩阵求解,提出了基于扩散路径映射的碳化细观模拟方法。方法基于Dijkstra路径算法对界面层影响进行修正,建立水泥浆体扩散路径算法,得到环境表面到水泥浆体的最短路径网络;通过水泥浆体代理模型,模拟水化反应、碳化反应以及材料孔隙率变化的耦合碳化过程,得到关键指标(氢氧化钙浓度)沿扩散路径的时变分布;最终依据相同的扩散路径长度进行结果映射,实现碳化作用中关键物质浓度随时间空间分布的高效精准预测。通过材料试验对比校验,扩散路径映射方法模拟结果能够准确反应混凝土碳化深度范围;与传统偏微分求解方法对比,扩散路径映射方法能够在细观尺度精准模拟关键物质空间分布情况,且求解效率提升20倍以上,存储空间需求降低为偏微分求解的2%以内。  相似文献   

3.
研究了以硫酸为催化剂的水热碳化法对蔗糖碳源进行碳化的过程,优化了硫酸溶液浓度、碳化反应温度以及碳化反应时间对蔗糖基碳材料收率的影响,获得最佳的碳化工艺条件。最后,通过红外光谱、热重分析和扫描电镜分析了蔗糖基碳材料的化学特性及其碳化机理。  相似文献   

4.
本文研究了掺入三种活性(高、中、低)MgO的碱矿渣砂浆(AASM)在加速碳化环境下的碳化深度和碳化后抗压强度保留率,并通过XRD、TG和MIP等手段研究了AASM的碳化前后水化产物和孔结构。结果表明:不同活性的MgO均可以降低AASM的碳化深度、提高AASM的抗压强度保留率;随着MgO活性的增加,MgO在AASM中反应越充分,生成更多的类水滑石填充孔隙,CO2向AASM内部扩散速率越慢;类水滑石和未完全反应的MgO可以与CO2发生反应,使得AASM碳化后保留更多的C-(A)-S-H凝胶,AASM的孔结构劣化程度越低,因而碳化后AASM的抗压强度和抗压强度保留率越高,碳化深度越小。  相似文献   

5.
在超重力反应沉淀法制备白炭黑的基础上,在沉淀反应的后期加入硅烷偶联剂,实现沉淀法白炭黑的原位改性。对原位改性和未改性的白炭黑表面状况进行了研究,表明原位改性过程可以使白炭黑表面向亲油性转变。原位改性技术将白炭黑的制备过程和改性过程一次完成,大大简化了疏水化白炭黑的生产工艺。  相似文献   

6.
白云石灰浆碳化反应动力学研究   总被引:2,自引:0,他引:2       下载免费PDF全文
通过对碳化反应速率影响因素的研究,计算出反应的活化能,推断出了碳化反应的机理———Ca(OH)2碳化属扩散控制过程,而Mg(OH)2碳化则为化学反应控制过程,并给出碳化反应的双膜理论模型。对确定最佳碳化反应条件,实现钙、镁分离具有理论指导意义。  相似文献   

7.
研究了钽粉真空碳化的反应机理.结果表明,在反应初期为化学反应动力学过程点后才过渡到扩散动力学过程,碳化反应符合缩核反应模型.在1500~1700℃的温度范围内,碳化反应的表观反应活化能为195.2kJ·mol-1,表观扩散活化能为138.1kJ·mol-1.  相似文献   

8.
从低品级菱镁矿中提取高纯氧化镁的研究   总被引:2,自引:0,他引:2  
采用低品级菱镁矿粉矿进行碳化浸出工艺试验,对菱镁矿的矿石性质及轻烧性能、氧化镁的消化过程和碳化浸出工艺参数进行了研究,获得wMgO大于99%的高纯氧化铗产品。  相似文献   

9.
纳米白炭黑的电子显微研究   总被引:1,自引:0,他引:1  
利用透射电镜(TEM)、X射线衍射仪(XRD)和能谱仪(EDS)等分析方法研究了硫酸沉淀法制备纳米白炭黑过程中体系反应温度和溶胶制备反应时间对制备过程的影响。实验发现,体系反应温度应控制在65~85%,酸溶胶制备反应时间应控制在0.5小时左右。该条件下制备的白炭黑经激光粒度仪分析表明,粒径小、粒度均匀,主要成分为SiO2。  相似文献   

10.
采用间歇鼓泡碳化法合成片形超细碳酸钙,考察了碳化反应温度、灰乳比重、搅拌转速、化学添加荆等因素对碳酸钙粒子形貌、粒径及径厚比的影响.得到了最佳工艺条件:碳化反应温度20~25℃,添加荆质量分数为1.5%~2.0%,灰乳比重d≤1.05,搅拌转速约400r/min.最终制得了粒度为2.0-3.0μm,最大径厚比为10~16,晶型为方解石的片形超细碳酸钙.  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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