Thermochimica Acta最新文献_第4页

Hydrogen-bond density controlled sub-Tg annealing peaks in fast-scanning-chip calorimeter heating scans of non-crystallized aliphatic polyamides 快速扫描芯片量热计加热扫描非结晶脂肪族聚酰胺时氢键密度控制的亚tg退火峰

IF 3.1 2区化学

Thermochimica Acta Pub Date : 2025-04-04 DOI: 10.1016/j.tca.2025.179997

René Androsch , Christoph Schick

{"title":"Hydrogen-bond density controlled sub-Tg annealing peaks in fast-scanning-chip calorimeter heating scans of non-crystallized aliphatic polyamides","authors":"René Androsch , Christoph Schick","doi":"10.1016/j.tca.2025.179997","DOIUrl":"10.1016/j.tca.2025.179997","url":null,"abstract":"<div><div>A series of aliphatic polyamides (PAs) including PA 6, PA 6.6, PA 6.10, PA 6.12, PA 11, and PA 12 has been subjected to physical aging and analyzed regarding changes of structure during annealing at temperatures around 50 to 100 K below the glass transition temperature (<span><math><msub><mi>T</mi><mi>g</mi></msub></math></span>) for periods up to few hours, employing fast scanning chip calorimetry (FSC). Annealing the amorphous glass of non-crystallized samples at such low temperatures produces endothermic sub-<span><math><msub><mi>T</mi><mi>g</mi></msub></math></span> annealing peaks at slightly higher temperature in subsequently recorded FSC heating scans, scaling in area with the time of annealing for a given annealing temperature. Variation of the annealing temperature furthermore indicates that the underlying process of structure-change slows down with decreasing annealing temperature but not disappears even 100 K below <span><math><mrow><mspace></mspace><msub><mi>T</mi><mi>g</mi></msub></mrow></math></span>. Most important, comparison of the behavior of the various PAs investigated reveals a distinct effect of the chemical structure such that the amount of structure-reorganization (glass relaxation and/or ordering) in a pre-defined period of time reduces with decreasing methylene-group sequence-length between amide groups. It appears that the amide-group concentration in the chains, which determines the density of the hydrogen-bond network to neighbored molecular segments, controls/restricts the re-arrangements of sub-nm sized molecular units.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"748 ","pages":"Article 179997"},"PeriodicalIF":3.1,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143820396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synergism study on tri-combustion of cornstalk, polyethylene and anthracite coal 玉米秸秆、聚乙烯和无烟煤三燃烧协同增效研究

IF 3.1 2区化学

Thermochimica Acta Pub Date : 2025-04-03 DOI: 10.1016/j.tca.2025.179998

Xiang Gou , Xuan Zhao , Surjit Singh , Mulin Zou , Zhaowei He

引用次数: 0

Thermal decomposition and thermal hazards analysis of typical organic peroxides with impurities 典型含杂质有机过氧化物的热分解及热危害分析

IF 3.1 2区化学

Thermochimica Acta Pub Date : 2025-03-31 DOI: 10.1016/j.tca.2025.179992

Weixin Li , Yang Liu , Xuefeng Gui , Ruixiang Zhou , Jiwen Hu , Shudong Lin

{"title":"Thermal decomposition and thermal hazards analysis of typical organic peroxides with impurities","authors":"Weixin Li , Yang Liu , Xuefeng Gui , Ruixiang Zhou , Jiwen Hu , Shudong Lin","doi":"10.1016/j.tca.2025.179992","DOIUrl":"10.1016/j.tca.2025.179992","url":null,"abstract":"<div><div>Organic peroxides in the chemical industry can cause safety risks due to instability, prompting an interest in their thermal stability to avoid dangers. This study investigated the thermal hazards and decomposition mechanisms of cumene hydroperoxide (CHP), dicumyl peroxide (DCP), di-<em>tert</em>-butyl peroxide (DTBP), 1,3-bis(<em>tert</em>-butylperoxyisopropyl)benzene (BIBP), and 2,5-dimethyl-2,5-di-(<em>tert</em>-butylperoxy)hexane (DBPH), and the influence of impurities on these compounds. The thermodynamic properties of these compounds were determined via differential scanning calorimetry (DSC), and their apparent activation energies were calculated by kinetic models. The adiabatic thermal decomposition characteristics were obtained via accelerating rate calorimetry (ARC), and the risk matrix assessment was employed. The decomposition products were characterized via gas chromatography-mass spectrometry (GC–MS), and the corresponding thermal decomposition pathways were proposed. The energy of each step in the proposed pathways was calculated using density functional theory (DFT). The results provide critical guidance for the safe application of these five organic peroxides within the chemical industry.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"748 ","pages":"Article 179992"},"PeriodicalIF":3.1,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Unraveling the influences of isothermal temperature, rock debris and water saturation on tight oil oxidation behavior and kinetics 揭示了等温温度、岩屑和含水饱和度对致密油氧化行为和动力学的影响

IF 3.1 2区化学

Thermochimica Acta Pub Date : 2025-03-31 DOI: 10.1016/j.tca.2025.179994

Yafei Chen , Mengyi Yan , Zhezhi Liu , Daijun Du , Hong Yin , Xiang Zhang , Donglin He , Ping Ouyang , Haifeng Gong , Wanfen Pu

{"title":"Unraveling the influences of isothermal temperature, rock debris and water saturation on tight oil oxidation behavior and kinetics","authors":"Yafei Chen , Mengyi Yan , Zhezhi Liu , Daijun Du , Hong Yin , Xiang Zhang , Donglin He , Ping Ouyang , Haifeng Gong , Wanfen Pu","doi":"10.1016/j.tca.2025.179994","DOIUrl":"10.1016/j.tca.2025.179994","url":null,"abstract":"<div><div>It is critical and fundamental to explore main influence factors on tight oil oxidation behavior and kinetics, which has not been well understood. In this work, thermal analysis and Coats-Redfern method were employed to comprehensively investigate main influence factors. Besides, the most appropriate reaction order (<em>n</em>) was analyzed to obtain kinetic parameters. It suggested three reaction regions with the activation energy variation, and distillation effect was remarkable. Apart from the surface area effect, the addition of rock debris and clay also had the strong catalytic ability to decrease threshold, peak, and ending temperatures. Besides, the <em>n</em> variation implied a more complex, possibly multi-step reaction mechanism. Water existence could strengthen the distillation effect and lower exothermic peaks via suppressing the reaction rate. Moreover, corresponding activation energies indicated the water could promote the oxidation reaction evolution under lower temperatures. From this study, it could provide new insights into the reaction model optimization and numerical simulation for the air injection process.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"748 ","pages":"Article 179994"},"PeriodicalIF":3.1,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143760093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Discriminant analysis and neural networks for the identification of phytopathogenic fungi by isothermal microcalorimetry 用等温微量热法鉴别植物病原真菌的判别分析和神经网络

IF 3.1 2区化学

Thermochimica Acta Pub Date : 2025-03-30 DOI: 10.1016/j.tca.2025.179993

Jerusalen Betancourt-Rodríguez , Juan Arturo Ragazzo-Sánchez , Teresa Sandoval-Contreras , Montserrat Calderón-Santoyo

{"title":"Discriminant analysis and neural networks for the identification of phytopathogenic fungi by isothermal microcalorimetry","authors":"Jerusalen Betancourt-Rodríguez , Juan Arturo Ragazzo-Sánchez , Teresa Sandoval-Contreras , Montserrat Calderón-Santoyo","doi":"10.1016/j.tca.2025.179993","DOIUrl":"10.1016/j.tca.2025.179993","url":null,"abstract":"<div><div>This study introduces an innovative method for identifying phytopathogenic fungi through the application of discriminant analysis based on thermokinetic parameters derived from integrated heat flow-time curves obtained via isothermal microcalorimetry. By merging machine learning techniques with multivariate analysis, the research develops a reliable automated tool for fungal identification based on thermogenic analysis. The canonical discriminant analysis effectively distinguishes among the genera <em>Colletotrichum, Penicillium</em>, and <em>Alternaria</em>, providing discriminant canonical variables that served as the foundation for training various machine learning models. Likewise, the neural network model achieved an impressive 95 % fit to the training data, with a low misclassification over around 10 %. The study also discusses the criteria for discrimination and proposes a microcalorimetric database aimed at enhancing future machine learning systems for the identification of phytopathogenic fungi. This methodology represents a pioneering approach that integrates microcalorimetric data analysis with advanced computational techniques, paving the way for more sophisticated and automated diagnostic tools in the field of plant pathology.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"748 ","pages":"Article 179993"},"PeriodicalIF":3.1,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermal decomposition of RDX/NC gun-propellants: A kinetic study RDX/NC推进剂的热分解动力学研究

IF 3.1 2区化学

Thermochimica Acta Pub Date : 2025-03-28 DOI: 10.1016/j.tca.2025.179989

Samuel Delbarre, Léo Courty

引用次数: 0

A novel phosphoryl imidazolate flame retardant for polyester-cotton blend fabrics: Flame retardancy, thermal behavior and mechanical properties 一种新型咪唑磷基涤棉混纺织物阻燃剂：阻燃性能、热性能和力学性能

IF 3.1 2区化学

Thermochimica Acta Pub Date : 2025-03-27 DOI: 10.1016/j.tca.2025.179991

Xiaoyun Zhang, Ping Li, Zhanna Liu, Huaifang Wang, Ping Zhu

{"title":"A novel phosphoryl imidazolate flame retardant for polyester-cotton blend fabrics: Flame retardancy, thermal behavior and mechanical properties","authors":"Xiaoyun Zhang, Ping Li, Zhanna Liu, Huaifang Wang, Ping Zhu","doi":"10.1016/j.tca.2025.179991","DOIUrl":"10.1016/j.tca.2025.179991","url":null,"abstract":"<div><div>Inspired by the disperse dye in thermosol dyeing for polyester and polyester- containing fabrics, a novel small-molecule phosphoryl imidazolate compound with phosphorus, nitrogen, and heterocyclic aromatic structure, 2-(1H-imidazol-1-yl)-5,5-dimethyl-1,3,2-dioxaphosphinane-2-oxide (DOPIM), was successfully synthesized and utilized to enhance the flame retardancy of polyester-cotton blend (PTCO) fabrics through a convenient dip-dry-cure (PDC) strategy. The FTIR and NMR were employed to detect the chemical structure of DOPIM. Furthermore, to investigate the enhancement of PTCO's flame retardancy by integration of DOPIM, the thermal stability, flammability, combustion behavior and physical properties of the samples were comprehensively assessed. The char residues of the treated PTCO in the nitrogen atmosphere increased to 12.86 % from 2.90 % of the PTCO at 700 °C. The DOPIM treated PTCO exhibited a LOI of 28.7 % and exceptional self-extinguishing performance, with a damage length of 36 mm. The PHRR and THR of the DOPIM-treated PTCO decreased by 33 % and 32 %. TG, CCT and TG-FTIR analysis of PTCO, along with other test results demonstrated that DOPIM not only facilitated the degradation and char formation of cotton fibers, reducing their flammability, but also significantly reduced the degradation rate of polyester fibers. The presence of char and nonflammable gases generated from both the cotton and DOPIM contributed to form a stable char in PTCO. This indicates that DOPIM effectively worked for both cotton and polyester, enhancing the overall fire resistance of the PTCO. Notably, the DOPIM had no significant negative effect on the mechanical properties, handle and whiteness of the PTCO. In summary, this work offered a convenient and effective method for fabricated fire-safety PTCO, which holds significant importance in safeguarding life and property.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"748 ","pages":"Article 179991"},"PeriodicalIF":3.1,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Insight of biopolymeric degradation and kinetic triplets of corn cob and its biochar using thermogravimetric analysis 用热重分析法研究玉米芯及其生物炭的生物聚合物降解和动力学三重体

IF 3.1 2区化学

Thermochimica Acta Pub Date : 2025-03-27 DOI: 10.1016/j.tca.2025.179990

Harsha Wakudkar, Parmanand Sahu

引用次数: 0

Exploring the thermal transformations of glucosamine-functionalized graphene oxide aimed at controlled fabrication of polycrystalline ceramic-graphene composites 探索氨基功能化氧化石墨烯的热转化，以控制制备多晶陶瓷-石墨烯复合材料

IF 3.1 2区化学

Thermochimica Acta Pub Date : 2025-03-26 DOI: 10.1016/j.tca.2025.179987

Piotr Wiecinski , Anna Wieclaw-Midor , Michal Kukielski , Artur Kasprzak , Joanna Tanska , Blanka Seredynska , Paulina Wiecinska

{"title":"Exploring the thermal transformations of glucosamine-functionalized graphene oxide aimed at controlled fabrication of polycrystalline ceramic-graphene composites","authors":"Piotr Wiecinski , Anna Wieclaw-Midor , Michal Kukielski , Artur Kasprzak , Joanna Tanska , Blanka Seredynska , Paulina Wiecinska","doi":"10.1016/j.tca.2025.179987","DOIUrl":"10.1016/j.tca.2025.179987","url":null,"abstract":"<div><div>Graphene oxide is commonly used as a precursor to graphene in ceramic-matrix composites, as it can be thermally reduced to reduced graphene oxide (r-GO) at much lower temperatures than those required for sintering of the ceramic materials. In wet forming methods, dispersibility of graphene oxide in aqueous medium can be enhanced through surface modification. In this study, thermogravimetry and differential thermal analysis coupled to mass spectrometry (TG/DTA-MS) were applied to analyze the thermal transformations of glucosamine-functionalized graphene oxide (GO) compared to non-functionalized GO, both of which are key components in the fabrication of ceramic-graphene composites. Measurements were conducted under two different atmospheres: air and argon, to assess the influence of oxidative and inert environments on thermal stability and decomposition processes. Mass spectrometry (MS) enabled the identification of gaseous by-products released during decomposition. The combined TG/DTA-MS technique provided valuable insights into the thermal stability, volatile emissions, and potential environmental impact of the analyzed samples. The paper also describes the advances in thermal analysis, showing the wide range of programming possibilities and sample loading. This integrated approach is essential for optimizing the sintering process of composite materials, exemplified by ZrO₂-graphene composites. Additionally, the paper highlights several applications of TG-MS in ceramics manufacturing, including additive manufacturing and colloidal processing. The different possibilities of measurement data processing are also presented.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"748 ","pages":"Article 179987"},"PeriodicalIF":3.1,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Oxidation and exothermic characteristics of particulate coal under water-immersion air‒drying and pre-oxidation effects 浸水风干和预氧化作用下颗粒煤的氧化和放热特性

IF 3.1 2区化学

Thermochimica Acta Pub Date : 2025-03-25 DOI: 10.1016/j.tca.2025.179986

Jiangkun Chao , Tao Wei , Ling Shen , Daimin Hu , Rongkun Pan , Xuefeng Han , Shuo Wei

引用次数: 0