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过氧化苯甲酸叔丁酯的热分解动力学研究及SADT推算 被引量:7
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作者 薛岩 石宁 +1 位作者 孙峰 吕志果 《化学研究与应用》 CAS CSCD 北大核心 2012年第4期630-634,共5页
研究了过氧化苯甲酸叔丁酯的热分解动力学及不同包装规格下的自加速分解温度(SADT),利用C600微量热仪测试了过氧化苯甲酸叔丁酯的热分解特征,得到升温速率分别为0.1 K/min、0.2 K/min、0.5 K/min、1 K/min下热流随时间的变化曲线,并使用... 研究了过氧化苯甲酸叔丁酯的热分解动力学及不同包装规格下的自加速分解温度(SADT),利用C600微量热仪测试了过氧化苯甲酸叔丁酯的热分解特征,得到升温速率分别为0.1 K/min、0.2 K/min、0.5 K/min、1 K/min下热流随时间的变化曲线,并使用Friedman等转化率法对所得的实验数据进行分析处理,得到了过氧化苯甲酸叔丁酯的分解反应活化能、指前因子等热动力学参数,推算了不同包装规格的过氧化苯甲酸叔丁酯的SADT。结果表明TBPB分解活化能及指前因子随转化率变化而变化,活化能范围为42-135.5 kJ/mol,指前因子范围为0.25-33.5,在25L聚乙烯桶包装下的SADT为59℃,50L下为52℃,200L下为46℃。 展开更多
关键词 过氧化苯甲酸叔丁酯 热分解 等转化率法 动力学参数 SADT
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Thermogravimetric Analysis of Swine Manure Solids Obtained from Farrowing, and Growing-Finishing Farms 被引量:4
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作者 Mahmoud Sharara Samy Sadaka 《Journal of Sustainable Bioenergy Systems》 2014年第1期75-86,共12页
The modern trend of increasing the number of pigs at production sites led to a noticeable surplus of manure. Separation of manure solids provides an avenue of their utility via thermochemical conversion techniques. Th... The modern trend of increasing the number of pigs at production sites led to a noticeable surplus of manure. Separation of manure solids provides an avenue of their utility via thermochemical conversion techniques. Therefore, the goal of this paper was to assess the physical and thermal properties of solid separated swine manure obtained from two different farms, i.e., farrowing, and growing-finishing, and to determine their pyrolysis kinetic parameters. Swine manure solids were dried and milled prior to assessing their properties. Differential and integral isoconversional methods (Friedman, and Flynn-Wall-Ozawa) were used to determine the apparent activation energy as a function of the conversion ratio. Significant differences were observed in the proximate, ultimate composition between both manure types. The higher heating value (HHV) for the manure solids from farrowing, and growing-finishing farms reached 16.6 MJ/kg and 19.4 MJ/kg, respectively. The apparent activation energy computed using Friedman and FWO methods increased with the increase in the degree of conversion. Between 10% and 40% degrees of conversion, the average activation energies, using Friedman method, were103 and 116 kJ/mol for the farrowing and growing-finishing manure solids, respectively. On the other hand, the same activation energies, calculated from FWO method, were 98 and 104 kJ/mol, for solid manure obtained from farrowing and growing-finishing farms, respectively. The findings in this study will assist in the effort to optimize thermochemical conversion processes to accommodate swine waste. This could, in turn, minimize swine production impacts on the surrounding ecologies and provide sustainable energy and biochar streams. 展开更多
关键词 MANURE SOLIDS THERMOGRAVIMETRIC Analysis PYROLYSIS isoconversional Methods
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Synthesis and characterization of a 1,3-dibutylimidazolium azide([BBIm][N_(3)]) : A promising green energetic ionic liquid
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作者 Nawel Matmat Amir Abdelaziz +6 位作者 Djalal Trache Achour Sabrina Ahmed Fouzi Tarchoun Hani Boukeciat Sourbh Thakur Weiqiang Pang Thomas M.Klapotke 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第8期1-15,共15页
In the pursuit of advancing imidazolium-based energetic ionic liquids (EILs),the current study is devoted to the synthesis and characterization of 1,3-dibutyl-imidazolium azide ([BBIm][N_(3)]),as a novel member in thi... In the pursuit of advancing imidazolium-based energetic ionic liquids (EILs),the current study is devoted to the synthesis and characterization of 1,3-dibutyl-imidazolium azide ([BBIm][N_(3)]),as a novel member in this ionic liquids class.The chemical structure of this EIL was rigorously characterized and confirmed using FTIR spectroscopy,1D,and 2D-NMR analyses.The thermal behavior assessment was conducted through DSC and TGA experiments.DSC analysis revealed an endothermic glass transition at T_(g)=-61℃,followed by an exothermic degradation event at T_(onset)=311℃.Similarly,TGA thermograms exhibited a one-stage decomposition process resulting in 100% mass loss of the sample.Furthermore,the short-term thermal stability of the azide EIL was investigated by combining the non-isothermal TGA data with the TAS,it-KAS,and VYA/CE isoconversional kinetic approaches.Consequently,the Arrhenius parameters(E_(a)=154 kJ·mol^(-1),Log(A/s^(-1))=11.8) and the most probable reaction model g(a) were determined.The observed high decomposition temperatures and the significantly elevated activation energy affirm the enhanced thermal stability of the modified EIL.These findings revealed that[BBIm][N_(3)]EIL can be a promising candidate for advanced energetic material application. 展开更多
关键词 1 3-dibutyl-imidazolium azide[BBIm][N_(3)] Energetic imidazolium-base ionic liquids 1D-/2D-NMR analyses Short-term thermal stability isoconversional approaches
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Isoconversional kinetic analysis of decomposition of bastnaesite concentrates with calcium hydroxide 被引量:4
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作者 Peng Cen Xue Bian Wenyuan Wu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第12期1361-1371,共11页
Isoconversional methods combined with thermogravimetry were applied to investigate the decomposition kinetics of bastnaesite concentrates with different amounts of calcium hydroxide added.The apparent activation energ... Isoconversional methods combined with thermogravimetry were applied to investigate the decomposition kinetics of bastnaesite concentrates with different amounts of calcium hydroxide added.The apparent activation energy was calculated,and the results indicate that the overall reaction involves more than one single step.The reaction with a lower content(<15 wt%)of calcium hydroxide can be divided into two steps,while the reaction with a higher content(>15 wt%)involves another step which denotes the decomposition of newly formed calcium carbonate during roasting.The activation energy increases with increasing amount of calcium hydroxide in the lower range(0-15 wt%).This is due to the resistance of calcium hydroxide to heat and mass transport,However,more calcium can promote the decomposition reaction more effectively and thus reduce the activation energy.Nonlinear fitting was performed by fitting the experimental data to Avrami-Erofeev model to determine the reaction model and pre-exponential factor.The theoretical models were proven to be reliable for kinetic prediction. 展开更多
关键词 BASTNAESITE Thermal analysis kinetics isoconversional method Calcium hydroxide Rare earths
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Synthesis, evaluation of kinetic characteristics and investigation of apoptosis of Cu^(2+)-modified ceria nano discs
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作者 K.Nusrath K.Muraleedharan 《Journal of Rare Earths》 SCIE EI CAS CSCD 2018年第10期1050-1059,共10页
Ceria nano discs were synthesized by the stepwise thermal decomposition strategy of the oxalate precursor. A series of Ce(1-x)CuxO2(x = 0, 0.02, 0.1, 0.2 and 0.3) nano sized oxide systems were prepared through the... Ceria nano discs were synthesized by the stepwise thermal decomposition strategy of the oxalate precursor. A series of Ce(1-x)CuxO2(x = 0, 0.02, 0.1, 0.2 and 0.3) nano sized oxide systems were prepared through thermal decomposition route. Kinetic characterization of formation of solid solution was made by isoconversional strategy under non-isothermal condition. Introduction of various reactant molar ratios of Cu2+:Ce4+ has a pivotal role in the creation of new oxygen vacancies, decomposition strategy,particle size and shape. Cu2+ doping(x = 0.02 and 0.1) damages the disc shaped morphology of ceria.Homogeneous distribution of Cu2+ on the oxalate precursor has a significant role in the catalyzing activity for the destruction of oxalate bond to oxide. 2 mol% doped Cu2+ promotes breaking of oxalate bonds in nitrogen atmosphere. In vitro cell viability assay illustrates enhanced toxicity to cancer cells with 10 mol% Cu2+ doped ceria. 展开更多
关键词 Nano disc isoconversional Oxygen vacancies Decomposition strategy Cell viability Rare earths
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Synthesis,characterization and thermolysis of lanthanide metal nitrate complexes with 1,10-phenanthroline,Part-95
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作者 Nibha B.P.Baranwal +1 位作者 Gurdip Singh Constantin G.Daniliuc 《Journal of Rare Earths》 SCIE EI CAS CSCD 2014年第6期545-552,共8页
The nitrate complexes of cerium, praseodymium and neodymium with 1,10-phenanthroline (phen) of general formula [Ln(phen)2(NO3)2(H2O)2]·NO3 (where, Ln=Ce, Pr and Nd) were prepared and characterized by X-... The nitrate complexes of cerium, praseodymium and neodymium with 1,10-phenanthroline (phen) of general formula [Ln(phen)2(NO3)2(H2O)2]·NO3 (where, Ln=Ce, Pr and Nd) were prepared and characterized by X-ray crystallography. Thermolysis of these complexes was investigated by simultaneous thermogravimetry (TG) and differential thermal analysis (DTA). Isothermal TG was taken to evaluate the kinetic parameters using model fitting as well as model free isoconversional methods. The thermolytic pathways were also suggested, which involves decomposition followed by ignition. All the three complexes had coordination number ten and showed multistep decompositions. In order to evaluate the response of rapid heating, ignition delay (Di) measurements were undertaken. The activation energies for ignition were found to decrease in the order: Nd〉Pr〉Ce. 展开更多
关键词 crystal structure metal nitrate kinetics isoconversional model fitting ignition delay rare earths
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Description of Mechanism Function about Dehydration of Cobalt Oxalate Dihydrate by Multiple Rates Isotemperature Method
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作者 LiLi-qing ChenDong-hua 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第2期239-246,共8页
A new method of the multiple rates isotemperature is proposed to define the most probable mechanismg(α) of thermal anlaysis; the iterative isoconversional procedure has been employed to estimate apparent activation e... A new method of the multiple rates isotemperature is proposed to define the most probable mechanismg(α) of thermal anlaysis; the iterative isoconversional procedure has been employed to estimate apparent activation energyE; the pre-exponential factorA is obtained on the basis ofE andg(α). By this new method, the thermal analysis kinetics triplet of dehydration of cobalt oxalate dihydrate is determined, apparent activation energyE is 99.84 kJ·mol?1; pre-exponential factorA is 3.427×109–3.872×109 s?1 and the most probable mechanism belongs to nucleation and growth,A m model, the range ofm is from 1.50 to 1.70. Key words multiple rates isotemperature method - isoconversional method - cobalt oxalate dihydrate - accomodation function - differential scanning calorimetry (DSC) CLC number O 636.1 Foundation item: Supported by the Key Foundation of the Science and Technology Committee of Hubei Province (2001ABA009)Biography: Li Li-qing (1977-), female, Master candidate, research direction: material synthesize and thermal analysis kinetics. 展开更多
关键词 multiple rates isotemperature method isoconversional method cobalt oxalate dihydrate accomodation function differential scanning calorimetry (DSC)
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Type Ⅰ kerogen-rich oil shale from the Democratic Republic of the Congo: mineralogical description and pyrolysis kinetics
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作者 Rajaa Bouamoud Ely Cheikh Moine +3 位作者 Raphaèl Mulongo-Masamba Adnane El Hamidi Mohammed Halim Said Arsalane 《Petroleum Science》 SCIE CAS CSCD 2020年第1期255-267,共13页
The Democratic Republic of the Congo holds important reserves of oil shale which is still under geological status.Herein,the characterization and pyrolysis kinetics of typeⅠkerogen-rich oil shale of the western Centr... The Democratic Republic of the Congo holds important reserves of oil shale which is still under geological status.Herein,the characterization and pyrolysis kinetics of typeⅠkerogen-rich oil shale of the western Central Kongo(CK)were investigated.X-ray diffraction,Fourier-transform infrared spectroscopy and thermal analysis(TG/DTA)showed that CK oil shale exhibits a siliceous mineral matrix with a consistent organic matter rich in aliphatic chains.The pyrolysis behavior of kerogen revealed the presence of a single mass loss between 300 and 550°C,estimated at 12.5%and attributed to the oil production stage.Non-isothermal kinetics was performed by determining the activation energy using the iterative isoconversional model-free methods and exhibits a constant value with E=211.5±4.7 kJ mol.1.The most probable kinetic model describing the kerogen pyrolysis mechanism was obtained using the Coats–Redfern and Arrhenius plot methods.The results showed a unique kinetic triplet confirming the nature of kerogen,predominantly typeⅠand reinforcing the previously reported geochemical characteristics of the CK oil shale.Besides,the calculation of thermodynamic parameters(ΔH~*,ΔS~*andΔG~*)corresponding to the pyrolysis of typeⅠkerogen revealed that the process is non-spontaneous,in agreement with DTA experiments. 展开更多
关键词 TypeⅠkerogen PYROLYSIS kinetics isoconversional methods MINERALOGY Central Kongo oil SHALE
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三羟基苯甲基氨基均三嗪与双酚A型环氧树脂的固化反应研究 被引量:2
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作者 张兴宏 黄丽华 戚国荣 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2008年第2期185-190,共6页
采用等转化率法研究了2,4,6-三(羟基苯甲基氨基)-均三嗪(MFP)与双酚A型环氧树脂(DGEBA)在等温和非等温条件下的固化反应行为,两种条件下MFP/DGEBA固化反应的表观活化能(Eα)均随转化率(α)增加呈先减后增的趋势(α=0.25时取得最小值).... 采用等转化率法研究了2,4,6-三(羟基苯甲基氨基)-均三嗪(MFP)与双酚A型环氧树脂(DGEBA)在等温和非等温条件下的固化反应行为,两种条件下MFP/DGEBA固化反应的表观活化能(Eα)均随转化率(α)增加呈先减后增的趋势(α=0.25时取得最小值).由于仲胺基和酚羟基对环氧基反应的不等活性,非等温固化反应时两种反应先后发生,形成Triazine-NCH2-CH(OH)-结构后,再形成ArO-CH2-CH(OH)-结构并产生交联,前后两阶段Eα分别为69.88、6.8 kJ.mol-1.对等温固化反应,由于起始反应温度高,仲胺基和酚羟基几乎同步与环氧基发生反应,两者的相互催化作用使反应前期Eα相对较低(59.1 kJ.mol-1),固化反应速度较快,引起体系粘度迅速增大,扩散控制反应提前,从而造成反应后期Eα(89.7 kJ.mol-1)相对较大. 展开更多
关键词 环氧树脂 固化 动力学 等转化率法
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Kinetics analysis of non-isothermal decomposition of Ag_2O-graphite mixture 被引量:1
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作者 Seyed Hadi SHAHCHERAGHI Gholam Reza KHAYATI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第9期2991-3000,共10页
The thermal decomposition kinetics of Ag2O-graphite mixture was systematically studied using a differential scanning calorimeter(DSC) in terms of model-fitting Malek approach, integral master plot method and model-f... The thermal decomposition kinetics of Ag2O-graphite mixture was systematically studied using a differential scanning calorimeter(DSC) in terms of model-fitting Malek approach, integral master plot method and model-free advanced isoconversional method of Vyazovkin. The results showed that the thermal decomposition occurred in two stages. The first step was the decomposition process of Ag2 O to form porous silver particles as a complex process with the participation of at least two mechanisms, and the second step corresponded to the structural change from porous particles to silver bulk crystals as a single-step process. 展开更多
关键词 AG2O advanced isoconversional method kinetic modeling Sestak–Berggren model
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Precipitation kinetics of NZ30K-Mg alloys based on electrical resistivity measurement 被引量:1
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作者 王小娜 韩利战 顾剑锋 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第6期1690-1697,共8页
The electrical resistivity of NZ30K-Mg alloy was measured at different heating rates during continuous heating to stud the precipitation kinetics.Two kinds of metastable phases,β" and β',formed during the heating.... The electrical resistivity of NZ30K-Mg alloy was measured at different heating rates during continuous heating to stud the precipitation kinetics.Two kinds of metastable phases,β" and β',formed during the heating.Kissinger method and differentia isoconversional method were employed to assess the precipitation kinetic parameters of NZ30K-Mg alloy,activation energy Eα an pre-exponential factor A'α.The fraction of transformation(α) and the precipitation sequence in NZ30K-Mg alloy were determinec Continuous heating transformation(CHT) and isothermal heating transformation(IHT) diagrams were further obtained for guidin the aging of NZ30K-Mg alloy.The analysis shows that the precipitation kinetic parameters of NZ30K-Mg alloy can be obtaine accurately using isoconversional method. 展开更多
关键词 NZ30K-Mg alloy precipitation kinetics differential isoconversional method continuous heating transformation isothermal heating transformation
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Evaluation of solvent-mediated phase transformation of glycine using oleic acid: Morphology and characterization study 被引量:1
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作者 Sevgi Polat Perviz Sayan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第9期1829-1836,共8页
The polymorphic phase transformation of β-glycine to α-glycine was carried out both in the absence and presence of various concentrations of oleic acid used as additive at 25 ℃ in a water/ethanol medium. The effect... The polymorphic phase transformation of β-glycine to α-glycine was carried out both in the absence and presence of various concentrations of oleic acid used as additive at 25 ℃ in a water/ethanol medium. The effects of oleic acid and its concentration on phase transformation time were determined by continuously measuring the ultrasonic velocity. The crystals obtained by the completion of the phase transformation were characterized by XRD, SEM, and TG/DTG. The XRD and SEM results indicated that oleic acid significantly impacted phase transformation time and the morphological characteristics of the crystals. In addition to SEM analysis, detailed crystal shape analysis was performed and the circularity, elongation, and convexity parameters were determined quantitatively. TG/DTG analyses were performed to investigate thermal decomposition behavior and to calculate the activation energies based on different kinetic models such as FWO, KAS, Starink, and Tang kinetic models. With the addition of oleic acid to the medium, the calculated activation energy values increased from 89.63–90.63 to153.8–155.4 kJ·mol^(-1). The activation energy values showed that oleic acid was adsorbed on the crystal surface;this result was supported by FTIR, elemental, and Kjeldahl analyses. 展开更多
关键词 GLYCINE Oleic acid CRYSTALLIZATION isoconversional methods Phase transformation
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Pyrolytic Degradation of Olive Waste Residue (OWR) by TGA: Thermal Decomposition Behavior and Kinetic Study
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作者 Khalideh Al bkoor Alrawashdeh Katarzyna Slopiecka +2 位作者 Abdullah A. Alshorman Pietro Bartocci Francesco Fantozzi 《Journal of Energy and Power Engineering》 2017年第8期497-510,共14页
Olive oil is an important food industry product in Mediterranean countries. Large quantities of OWR (olive waste residue) are generated during a two- or three-phase separation process. This represents a major pollut... Olive oil is an important food industry product in Mediterranean countries. Large quantities of OWR (olive waste residue) are generated during a two- or three-phase separation process. This represents a major pollution problem for the industry and oil farms. The OWR is a source of substances of high value and can be used as a low-cost renewable energy. This work studied the behaviour of OWRs during the thermal decomposition process. The experiments of the slow pyrolysis process of three different waste olive products as olive pomace, olive tree pruning and olive kernels were performed under a nitrogen atmosphere at different heating rates, using a thermogravimetric balance. The samples were heated to a maximum temperature of 1,023 K, with four different heating rates of 2, 5, 10, 15 K/min. A comparison of different isoconversional (Flynn-Wall-Ozawa), not-isoconversional (Kissinger) model-free and model-fitting (Freeman-Carroll) methods to calculate the activation energy and pre-exponential factor is presented. In the Kissinger method the kinetic parameters were invariant for the whole pyrolysis process. While, in the case of Freeman-Carroll, it differs with change of the heating rate. The Flynn-Wall-Ozawa technique revealed the "not one-step" mechanism of reaction that occurs during the slow pyrolysis process. The kinetic data obtained in nitrogen atmosphere may provide more useful information for engineers for a better and complete description of the pyrolysis process and can be helpful to predict the kinetic model. 展开更多
关键词 THERMOGRAVIMETRY KINETICS BIOMASS isoconversional methods OWR model-fitting methods model-free methods.
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Reaction pathway and kinetics of CdO nanoparticles prepared from CdCO_3 precursor using thermal decomposition method
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作者 Gholam Reza KHAYATI Seyed Hadi SHAHCHERAGHI +1 位作者 Vahid LOTFI Esmael DAREZARESHKI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第4期1138-1145,共8页
The non-isothermal kinetics of CdO nanoparticles prepared from CdCO3 precursor using thermal decomposition method was investigated. A model-fitting Malek approach and a model-free advanced isoconversional method of Vy... The non-isothermal kinetics of CdO nanoparticles prepared from CdCO3 precursor using thermal decomposition method was investigated. A model-fitting Malek approach and a model-free advanced isoconversional method of Vyazovkin were applied to the analysis of the DSC and TGA data. The results showed that CdO nanoparticles prepared from CdCO3 followed an autocatalytic reaction. Sestak–Berggren model could favorably describe the studied reaction process. Moreover, the apparent activation energy of CdCO3 decomposition was calculated to be (119.19±9.97) kJ/mol and the explicit rate equation form of CdCO3 decomposition was established. 展开更多
关键词 CdCO_3 CdO nanoparticle kinetic modeling thermal decomposition advanced isoconversional method
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环氧树脂/活化纳米氧化铝复合材料的固化动力学 被引量:22
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作者 周红军 尹国强 +2 位作者 林轩 葛建芳 庄妙红 《化工学报》 EI CAS CSCD 北大核心 2011年第6期1749-1755,共7页
采用氢氧化钠溶液将纳米氧化铝表面活化,利用γ-缩水甘油醚氧丙基三甲氧基硅烷(KH560)和环氧树脂对活化纳米氧化铝进行表面处理而引入环氧基团。采用差示扫描量热法(DSC)研究复合材料的非等温固化行为,分析了活化纳米氧化铝及其环氧功... 采用氢氧化钠溶液将纳米氧化铝表面活化,利用γ-缩水甘油醚氧丙基三甲氧基硅烷(KH560)和环氧树脂对活化纳米氧化铝进行表面处理而引入环氧基团。采用差示扫描量热法(DSC)研究复合材料的非等温固化行为,分析了活化纳米氧化铝及其环氧功能化产物对环氧树脂固化动力学参数与机理的影响,运用等转化率方法包括Friedman方法与KAS方法研究了复合材料固化活化能与转化率的关系。实验结果表明,活化纳米氧化铝及其环氧功能化产物降低了固化体系的理论凝胶温度,对固化反应有促进作用;纳米氧化铝的加入使固化反应活化能增大,后固化温度提高,当加入2%的KH560改性活化纳米氧化铝,凝胶温度降低了6.5℃,而后固化温度提高了17.5℃,但对反应级数影响不大。 展开更多
关键词 环氧树脂 活化纳米氧化铝 固化动力学 等转化率法
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二水草酸锌脱水的热分解动力学研究 被引量:17
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作者 张伟南 袁誉洪 +1 位作者 李丽清 陈栋华 《物理化学学报》 SCIE CAS CSCD 北大核心 2004年第1期33-37,共5页
提出一种多升温速率-等温法确定机理函数g(α)的新方法;并用迭代的等转化率法求出较为可靠的活化能Ea;在Ea和g(α)的基础上计算出指前因子A.用该法对二水草酸锌(ZnC2O4·2H2O)脱水反应的热分解动力学三因子进行了求算,得出Ea为87.22... 提出一种多升温速率-等温法确定机理函数g(α)的新方法;并用迭代的等转化率法求出较为可靠的活化能Ea;在Ea和g(α)的基础上计算出指前因子A.用该法对二水草酸锌(ZnC2O4·2H2O)脱水反应的热分解动力学三因子进行了求算,得出Ea为87.22kJ·mol-1,A为4.2120×108~7.2328×108s-1;以及随机成核和随后生长型机理函数Am(Avrami-Erofeer),其积分形式g(α)=犤-ln(1-α)犦m-1和微分形式f(α)=m(1-α)·犤-ln(1-α)犦(1-m-1),调节因子m=1.85~2.00. 展开更多
关键词 二水草酸锌 脱水反应 热分解动力学 多升温速率-等温法 等转化率法 活化能 机理函数 非等温动力学 指前因子
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非线性等转化率的微、积分法及其在含能材料物理化学研究中的应用——Ⅰ.理论和数值方法 被引量:19
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作者 胡荣祖 赵凤起 +2 位作者 高红旭 张海 松全才 《含能材料》 EI CAS CSCD 2007年第2期97-100,共4页
推导了从定温和不定温数据计算表观活化能(Eα)的8个典型非线性等转化率微、积分方程。提出了通过这8个方程计算含能材料分解反应Eα值的数值方法。
关键词 物理化学 含能材料 非线性等转化率微分法 非线性等转化率积分法 分解反应 表观活化能
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等温热重分析法对煤焦反应动力学特性研究 被引量:19
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作者 孙锐 廖坚 +2 位作者 Leungo Kelebopile 李志刚 张旻晓 《煤炭转化》 CAS CSCD 北大核心 2010年第2期57-63,共7页
针对工业气化炉二级旋风分离器的气化后半焦,同时选取京能烟煤在1173K,1273K和1373K三个温度下快速热解焦炭作为比较,在TGA/SDTA851e型热重分析仪上,对四种经历不同热过程的焦炭进行等温热重实验,实验温度范围为773K~1023K,研究煤焦燃... 针对工业气化炉二级旋风分离器的气化后半焦,同时选取京能烟煤在1173K,1273K和1373K三个温度下快速热解焦炭作为比较,在TGA/SDTA851e型热重分析仪上,对四种经历不同热过程的焦炭进行等温热重实验,实验温度范围为773K~1023K,研究煤焦燃烧反应动力学特性及其影响因素.煤焦制取方式和热解温度的不同决定了煤焦反应性的不同,在这四种煤焦中,气化半焦JC的反应性最小,而京能烟煤三种热解煤焦的反应性随着热解温度的升高而减小.随着燃烧温度和氧含量的升高,煤焦的反应速率在增大.同时,用半转化率法确定了煤焦燃烧的转捩温度和各个反应区域的活化能,在化学反应动力区,JC,JN-1,JN-2和JN-3活化能分别为115kJ/mol,57kJ/mol,70kJ/mol和97kJ/mol,与等转化率法所求得的平均活化能相近.随着煤焦转化率的增大,反应越来越困难,活化能也在增大,而且煤焦燃烧反应离开化学反应动力区的转捩温度也在升高. 展开更多
关键词 等温热重 煤焦燃烧反应性 半转化率法 等转化率法 化学反应动力学
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采用等转化率法研究油页岩热解的动力学特性 被引量:11
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作者 王擎 徐峰 +3 位作者 孙佰仲 刘洪鹏 李少华 关晓辉 《中国电机工程学报》 EI CSCD 北大核心 2007年第26期35-39,共5页
以热分析法(TG、DTG)为手段,对桦甸油页岩在不同升温速率(10、20、40、100℃/min)下的热解动力学进行了研究,用等转化率法(Friedman法)求取了桦甸两种油页岩样品的热解反应表观活化能;用Sestak复杂机制对反应机理进行拟合,得到了反应机... 以热分析法(TG、DTG)为手段,对桦甸油页岩在不同升温速率(10、20、40、100℃/min)下的热解动力学进行了研究,用等转化率法(Friedman法)求取了桦甸两种油页岩样品的热解反应表观活化能;用Sestak复杂机制对反应机理进行拟合,得到了反应机理函数,最后确定了频率因子A。研究结果表明,在整个转化率范围内,热解活化能并不是一个定值,但在[0.1,0.9]的范围内,活化能随转化率的变化曲线平缓;油页岩热解反应机理复杂,主要以成核机制所控制。 展开更多
关键词 油页岩 热分析 动力学 等转化率法 反应机理
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亚麻纤维热解动力学的“model free”法和Coats-Redfern模型拟合法研究 被引量:11
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作者 许桂英 Watkinson A.Paul +1 位作者 Ellis Naoko 孙国刚 《化工学报》 EI CAS CSCD 北大核心 2010年第9期2480-2487,共8页
亚麻纤维是一种潜在的气化原料,本文对亚麻纤维的热解行为进行了热重分析研究。10mg粒径为0.60~0.85mm的亚麻纤维颗粒在高纯氮气的保护下分别以10、20、30、50K.min-1的升温速率线性升温到550℃。使用"model free"方法和Coats-Redfer... 亚麻纤维是一种潜在的气化原料,本文对亚麻纤维的热解行为进行了热重分析研究。10mg粒径为0.60~0.85mm的亚麻纤维颗粒在高纯氮气的保护下分别以10、20、30、50K.min-1的升温速率线性升温到550℃。使用"model free"方法和Coats-Redfern模型拟合方法分析亚麻纤维的热解过程,并估算出热解反应的表观活化能。本文中"model free"方法包括Friedman、Flynn-wall-Ozawa、Vyazovkin and Wight三种等转化率方法及Kissinger法。三种等转化率方法均得到活化能随着转化率的升高而升高的规律。四种"model free"方法显示亚麻纤维的活化能主要在155~175kJ·mol-1之间,使用模型拟合方法所获得亚麻纤维热解反应的活化能值在175kJ·mol-1左右,使用模型拟合方法和"model free"方法所得的活化能值接近。这些活化能值可以为亚麻纤维高效的热化学利用提供基础数据。 展开更多
关键词 等转化率法 活化能 MODEL free Coats-Redfern
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