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51.
石油焦与煤混合燃料热重分析研究 总被引:6,自引:0,他引:6
石油焦与煤混合燃烧是高效处理石油焦的有效方法,作者对选用的石油焦和煤不同配比的混合燃料进行了热重分析研究。使用常压高温热天平研究、分析了各配比混合燃料的热解特性和燃烧特性。并根据化学动力学方法计算了各过程的化学动力学参数,即活化能E和频率因子A0。结果表明,各混合燃料热解起始温度大致相同,随煤焦比减小,挥发分析出速率变缓,最大释放速度所对应的温度升高,最终失重率减小,挥发分释放特性指数减小;随煤焦比增大,混合燃料着火温度和燃尽温度逐渐降低,最大燃烧速率所对应的温度降低,燃烧特性指数增大;随煤焦比减小,活化能和频率因子增大。 相似文献
52.
Cu-Mg/Al复合氧化物催化碳颗粒物燃烧性能的研究 总被引:5,自引:0,他引:5
恒定二价与三价阳离子比为3(nM2+/nM3+=3),采用共沉淀法制备不同Cu含量的系列水滑石前驱物, 800 ℃焙烧4 h形成复合氧化物(CuO质量百分数分别为0%、5%、10%、15%、20%、30%、40%)用作柴油车排放碳颗粒物燃烧的催化剂,并采用XRD、BET、TG-DSC、FT-IR、TPR等表征手段研究了Cu、Mg含量对材料前驱物物化性能的影响及对其衍生复合氧化物催化碳颗粒物燃烧性能的影响.结果表明,Cu、Mg含量对材料的热稳定性、比表面和催化氧化活性有显著的影响. Mg有助于提高催化剂的热稳定性; Cu含量增加,催化剂比表面下降,但比表面不是影响催化剂活性的主要因素. CuO含量为15%时,催化剂具有最好的催化活性和稳定性,碳颗粒物的起燃温度(T10)和半转化温度(T50)分别为336 ℃和409 ℃.在CuO含量≤30%时可以形成结构完整的水滑石前驱物, CuO含量为40%时出现Cu(OH)2杂相; CuO含量< 20%时,经高温焙烧可得到均匀的复合氧化物, CuO含量≥20%时出现CuO偏析. TPR结果表明焙烧温度和复合氧化物的组成决定了材料的可还原性能. 相似文献
53.
Lebedev B. V. Kulagina T. G. Smirnova N. N. Shifrina Z. B. Averina M. S. Rusanov A. L. 《Journal of Thermal Analysis and Calorimetry》2003,74(3):735-748
In an adiabatic vacuum calorimeter, the temperature dependence of the heat capacity C
p of phenylated polyphenylene and initial comonomer 1,4-bis(2,4,5-triphenylcyclopentadienone-3-yl)benzene was studied between
6 and 340 K with an uncertainty of about 0.2%. In a calorimeter with a static bomb and an isothermal shield their energies
of combustion DUcomb were measured. From the experimental data, the thermodynamic functions C
p
0 (T), H
0(T)-H
0(0), S
0(T)-S0(0), G
0(T)-H
0(0) were calculated from 0 to 340 K, and standard enthalpies of combustion ΔH
comb
0 and thermodynamic parameters of formation-enthalpies ΔH
f
0, entropies ΔH
f
0, Gibbs functions ΔG
f
0 - of the substances studied were estimated at T=298.15 K at standard pressure. The results were used to calculate the thermodynamic characteristics (ΔH
f
0 ,ΔS
f
0, ΔG
f
0) of phenylated polyphenylene synthesis in the range from 0 to 340 K.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
54.
A combined method for determination of the standard enthalpies of formation of nitroform and its salts was proposed. The enthalpies
of dissolution of nitroform and its ammonium, hydrazinium, guanidinium, and potassium salts in water were measured. The enthalpy
of combustion of hydrazinium salt of nitroform was determined by a combustion calorimetry, and its standard enthalpy of formation
was calculated. The enthalpy of formation of trinitromethyl anion in indefinitely diluted aqueous solution −24.94±0.79 kJ
mol−1, was calculated on the basic of the data obtained for enthalpies of formation and dissolution of ammonium and hydrazinium
salts of nitroform. Standard enthalpies of formation of nitroform and its salts were calculated.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2451–2454, December, 1998. 相似文献
55.
Sabyasachi Gaan 《Polymer Degradation and Stability》2007,92(6):968-974
The effect of six organophosphorus compounds, including Pyrovatex CP (PCP), diammonium phosphate (DAP), phosphoric acid (PA), tributyl phosphate (TBP), triallyl phosphate (TAP) and triallyl phosphoric triamide (TPT) on the flame retardancy of cotton cellulose was studied. PCP, PA, and DAP are more efficient compared with the other three compounds in improving the limiting oxygen index (LOI) of cotton. The effectiveness of these compounds was investigated using scanning electron microscope (SEM) images of char formed after LOI tests, char content, activation energy of decomposition and heat of combustion data. SEM images showed that DAP, PCP and PA chars maintain the surface morphology during the burning process, which might be due to the formation of a protective layer or crosslinking effect. PA, PCP, and DAP treated fabrics have a higher activation energy of decomposition, higher char content and lower heat of combustion. 相似文献
56.
57.
The enthalpies of combustion (ΔH
comb) of five primary, secondary, and tertiary alkyl(aryl)arsines in the condensed state were calculated using the equation ΔH
comb = −385.8–110.3N, where N is the number of bond-forming electrons. The dependence presented is used for the calculation of the enthalpies of combustion
of full esters and amidoesters of arsinous acid of noncyclic and cyclic structures.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1042–1043, May, 2007. 相似文献
58.
Naomi Masuda Yatsuhisa Nagano T. Kimura 《Journal of Thermal Analysis and Calorimetry》2005,81(3):533-535
Summary The standard molar enthalpy of formation of methyl methylthiomethyl sulfoxide, CH3(CH3SCH2)SO, at T=298.15 K in the liquid state was determined to be -199.4±1.5 kJ mol-1 by means of oxygen rotating-bomb combustion calorimetry. 相似文献
59.
Yu H. G. Yu Dong J. X. Qin C. Q. Liu Y. Qu S. S. 《Journal of Thermal Analysis and Calorimetry》2004,75(3):807-813
The energy of combustion of crystalline 3,4,5-trimethoxybenzoic acid in oxygen at T=298.15 K was determined to be -4795.9±1.3 kJ mol-1 using combustion calorimetry. The derived standard molar enthalpies of formation of 3,4,5-trimethoxybenzoic acid in crystalline
and gaseous states at T=298.15 K, ΔfHm
Θ (cr) and ΔfHm
Θ (g), were -852.9±1.9 and -721.7±2.0 kJ mol-1, respectively. The reliability of the results obtained was commented upon and compared with literature values.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
60.
I. Zięborak-Tomaszkiewicz 《Journal of Thermal Analysis and Calorimetry》2006,83(3):611-615
The energies of combustion
in fluorine of gallium nitride and indium nitride in wurzite crystalline structure
have been measured in a two-compartment calorimetric bomb, and new standard
molar enthalpies of formation have been calculated: ΔfHm0(GaN(cr)
298.15 K)= –(163.7±4.2) kJ mol–1
and ΔfHm0(InN(cr) 298.15 K)= –(146.5±4.6) kJ mol–1
. Comparison with the recommended values of the ΔfHm0 nitrides
from the literature is also presented. 相似文献