木炭高温水蒸气气化的模拟分析

依据吉布斯能最小化原理,选用温度和S/C(水蒸气量与木炭量之比)作为高温水蒸气气化的影响因素,对木炭高温水蒸气气化的产品气特性进行了模拟分析和预测。模拟研究表明,S/C和温度对气化产品气的影响存在交互作用,S/C的增加可有效提升产品气中H_2的含量并降低CO含量,温度的提升可有效提高CO含量,并给出了组分含量H_2/CO、热值和气体产率等评价指标的变化范围和规律。当S/C1.0,温度600~1 200℃时,产品气的H_2/CO范围为1.0~3.71,热值范围为8.6~12.24 MJ/Nm~3。同时,通过自行设计的实验台对模拟分析结果进行了实验验证。结果表明,模拟计算的气体组分含量基本与实验结果一致,其中模拟与实验的H_2和CO含量偏差小于5%。     

贝壳脱除垃圾焚烧烟气中氯化氢的实验研究

为解决海岛生活垃圾焚烧中消除HCl问题,研究贝壳代替传统钙基吸附剂可行性。利用贝壳、Ca(OH)_2和Ca CO_3对高温模拟烟气进行HCl吸附实验,讨论了温度、吸附剂成分、吸附反应平衡和Ca/Cl物质的量之比对吸附剂脱氯性能的影响。结果表明,温度高于700℃时,贝壳的脱氯效果优于Ca(OH)_2和Ca CO_3;贝壳与钙基吸附剂脱氯规律有相似之处,高温下,Ca(OH)_2首先转化为Ca CO_3来发挥吸附作用;而贝壳主要成分为Ca CO_3;温度高于700℃时,贝壳吸附HCl反应的平衡浓度与Ca(OH)_2和Ca CO_3相当或更低;综合热值、脱氯效率等因素,最佳贝壳投加量为垃圾总量的9%～13%。     

CaO中高温脱除HCl的特性试验研究

为在中高温下脱除垃圾焚烧烟气中的HCl,在不同初始HCl浓度(450~1 500 mg/m3)、反应温度(300~700℃)以及吸附剂粒径(0.15~2 mm)条件下对CaO脱氯特性进行了试验,并采用扫描电子显微镜(SEM)和能谱仪(EDS)对反应过程中的CaO颗粒进行分析.试验结果表明:随初始HCl浓度的减小,CaO对HCl的吸附能力升高,当HCl浓度为750 mg/m3时CaO转化率最高(12.20%),浓度继续减小,CaO转化率不变;随着反应温度升高,CaO转化率呈现先上升后下降的趋势,并在400℃达到峰值;CaO对HCl的吸附能力随粒径的减小而增加,当粒径范围从1~2 mm减小到0.150~0.355 mm时,CaO转化率提高7.78%.由SEM和EDS可见,未反应的CaO表面疏松多孔,随着与HCl反应的进行,颗粒结构变得致密且表面逐渐被反应产物CaCl2所覆盖,当颗粒表面完全被产物层包裹时吸附剂失效.     

高温煤气中氯化氢和碱金属蒸气的脱除

对高温煤气中的氯化氢和碱金属蒸气进行了单独和同时脱除的研究,单独脱除的研究得出,脱氯剂的氯容量随反应温度的增在而提高,试验所选的5种吸附剂对碱金属都具有脱除性能,其中以高铝土和活性Al2O3吸附剂的吸附效率最高,在840度条件下活性Al2O3吸附剂对碱金属化合物的脱除主要以物理吸附的方式进行,在HCl气体和碱金属蒸气同时存在条件下,高铝土脱除碱金属的效率高达79．5％。TCl1脱氯剂脱除HCl气体的效率为100％。     

滤料负载飞灰-CaO吸附剂脱除Hg~0的试验研究

在固定床试验系统上,进行了自制不同质量掺混比的飞灰-CaO吸附剂对燃煤烟气中Hg0的脱除试验,确定了飞灰和CaO的质量掺混比为2∶1时飞灰-CaO吸附剂对Hg0的脱除效率最佳,最大脱除效率达34%.在此基础上制备纤维滤料负载飞灰-CaO吸附剂,并对燃煤烟气中Hg0的脱除进行试验,研究飞灰-CaO吸附剂粒径、吸附反应温度、入口Hg0浓度和HCl气氛因素对Hg0脱除效率的影响.结果表明:飞灰-CaO吸附剂粒径为43～75μm时,Hg0脱除效率较高;吸附反应温度越高,Hg0脱除效率越低;入口Hg0浓度的提高并不一定提高Hg0脱除效率;烟气中加入HCl气体后,Hg0的脱除效率有明显的上升,且Hg0的脱除效率随HCl含量的增加而提高.     

类水滑石与常规吸附剂中高温脱除HCl实验研究

为获得中高温条件下高效脱除烟气中HCl的吸附剂,对自制类水滑石吸附剂HTL与常用的吸附剂CaO,NaHCO3在不同温度(300~700℃)、不同HCl初始浓度(750~1 500 mg/m3)以及不同反应时间条件下对HCl的脱除特性进行了比较研究.结果表明:随HCl初始浓度的升高、反应时间的延长,CaO,NaHCO3的脱除效率都呈下降趋势;随温度升高,CaO对HCl的脱除效率一直呈下降趋势,而NaHCO3对HCl的脱除效率先下降,在550℃后又呈现上升趋势,并且在温度高于600℃时NaHCO3,CaO均出现了结块和熔融现象;而以上各条件对HTL的影响不大,其脱除效率一直高于95%.     

林业废弃物氧气-水蒸气气化的Aspen Plus模拟

基于Aspen Plus软件对林业废弃物氧气-水蒸气气化进行模拟计算,并对比模拟结果与试验结果以验证模型的可靠性,研究了气化温度、气化压力、当量比及水蒸气与废弃物的质量配比(S/F)对气化特性的影响.结果表明:随着温度升高气体产物中H2和CO含量增加,同时气化效率也相应增加,800℃时气化效率达到最高值为87.38%;压力增大时气体产物中H2,CO含量减少,但干气体产物的CH4含量及气体热值迅速增大;气化的最佳当量比约为0.22,过高或过低均会导致可燃组分和气化效率的下降;S/F增大时,气体产物中CO2,H2含量增多,CO含量减少,当S/F≥0.5时气化效率达到最大值并保持不变.     

木屑与PVC混烧中HCl排放特性的实验研究

在管式炉实验平台上研究O_2/CO_2气氛下反应温度、吸收剂种类、气氛、钙氯比以及燃料混合比等因素对木屑与PVC混烧过程中脱氯效率的影响,结果表明:随温度的升高,脱氯效率先增大后减小,在700℃时获得最高的脱氯效率(71. 4%);添加剂比例及种类也会对脱氯产生一定的影响,改性CaCO_3的孔隙结构更加丰富,比表面积相对增大,在高温下具有较高的脱氯率;随着混合物中木屑比例的上升,脱氯率有所增大; O_2/CO_2气氛下的脱氯率大于O_2/N_2气氛下的脱氯率.对吸附剂和燃烧产物进行的BET和SEM/EDS分析表明:产物颗粒表面覆盖着一层致密的CaCl2,阻止了HCl穿透颗粒表面进入脱氯剂内部的充分反应,使脱氯效率降低.     

高炉内氯元素对焦炭高温冶金性能的影响

为探索不同形式氯元素对焦炭高温冶金性能的影响规律,在对高炉内含氯化合物进行反应热力学分析的基础上,通过实验研究HCl气体、CaCl_2溶液和HCl溶液等3种不同含氯化合物对焦炭反应性(CRI)和反应后强度(CSR)的影响。结果表明,由原燃料带入高炉的氯元素多和其它物质反应生成HCl气体,当煤气中HCl气体体积分数在0~1.8%范围内增加时,焦炭的反应性先升高再降低,反应后强度先降低再升高;煤气中HCl气体体积分数为0.6%时,焦炭的高温冶金性能劣化最严重;HCl溶液和CaCl_2溶液的质量分数分别在0~8%范围内增加时,焦炭的反应性均逐渐提高,反应后强度均逐渐降低。因此,高炉内不同形式的氯元素对焦炭高温冶金性能均有劣化作用。建议高炉生产现场建立氯元素的检测制度,控制入炉的氯元素含量,以减少对焦炭高温冶金性能的影响。     

一种新型高温煤气脱氯剂的研究

以价廉易得的天然矿物及碱为化学活性组分，制得一种新型高温煤气脱氯剂GH1，该脱氯剂在650℃高温，空速2500h^-1和进口HCl气体体积浓度1500mg/m^3-2000mg/m^3条件下的穿透氯容量达到37.2%，同时机械强度合格，实验还考虑了主要成分配比，空速和温度对脱氯性能的影响，并讨论了有关机理。     

Markedness and its Interpretation in Language Use

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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