Thermochimica Acta最新文献_第4页

Thermal degradation of Luffa cylindrica Fiber modified by distilled water, saline water and diesel oil 蒸馏水、盐水和柴油改性丝瓜纤维的热降解研究

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2026-02-01 Epub Date: 2025-12-23 DOI: 10.1016/j.tca.2025.180206

Juan F.G. Alba , Luciana L. Melo , Hyago M. Cavalcanti , Jose G.A. Pacheco , Roger Fréty , Rosangela R.L. Vidal

Luffa cylindrica fiber is widely used as an adsorbent for contaminants in water, but after use, it becomes chemical waste. This study investigates the thermal degradation of Luffa biomass after its modification with potential pollutants. The fiber was pretreated with saline water or diesel oil to simulate contamination and was compared to a reference fiber washed with deionized water. After drying, the samples were characterized using SEM/EDS microscopy. Subsequently, they underwent slow pyrolysis through thermogravimetric analysis and rapid micro-pyrolysis at 873 K. Thermogravimetric results under nitrogen indicate that these pretreatments affect the samples’ decomposition profiles. The presence of inorganic salts caused a slight catalytic effect during the decomposition of hemicellulose and cellulose under nitrogen, reducing the maximum peak decomposition temperature of hemicellulose by 38 K. Inorganic salts also exhibited inhibitory effects during the high-temperature combustion of biochar formed. In diesel-contaminated biomass, diesel can be practically removed without transformation before the Luffa fiber components begin to decompose at higher temperatures. The possibility of recovering an important fraction of diesel oil was also demonstrated in the micro-pyrolysis results. This study confirms that different pretreatments significantly affect Luffa decomposition mechanisms, suggesting that, in studies of biomass transformation, researchers must consider that initial cleaning processes can generate sample modifications. This method is also helpful for assessing the reuse of spent Luffa biomass for bioenergy generation.

丝瓜纤维作为水中污染物的吸附剂被广泛使用，但使用后成为化学废弃物。研究了丝瓜生物质经潜在污染物改性后的热降解情况。用盐水或柴油对纤维进行预处理以模拟污染，并与用去离子水洗涤的参考纤维进行比较。干燥后，用SEM/EDS显微镜对样品进行表征。随后，通过热重分析缓慢热解，并在873 K下进行快速微热解。氮下的热重分析结果表明，这些预处理对样品的分解曲线有影响。无机盐的存在对半纤维素和纤维素在氮气条件下的分解有轻微的催化作用，使半纤维素的最高分解峰温度降低了38 K。无机盐在生物炭高温燃烧过程中也表现出抑制作用。在柴油污染的生物质中，在丝瓜纤维成分在较高温度下开始分解之前，柴油实际上可以在不转化的情况下被去除。微热解结果也证明了回收柴油重要组分的可能性。本研究证实，不同的预处理对丝瓜的分解机制有显著影响，这表明，在生物质转化的研究中，研究人员必须考虑到初始清洗过程可能会产生样品修饰。该方法也有助于评估废弃丝瓜生物质用于生物能源发电的再利用。

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引用次数: 0

Gasification mechanism and product analysis of resin wastes: an integrated study of TG-FTIR-MS and kinetic modeling 树脂废弃物的气化机理及产物分析：TG-FTIR-MS和动力学建模的综合研究

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2026-01-01 Epub Date: 2025-12-01 DOI: 10.1016/j.tca.2025.180197

Liyan Chen , Qian Liu , Yinsheng Jiang , Wenqi Zhong , Wenli Dong

With the growing challenge of electronic waste (e-waste), this study explores CO₂-assisted gasification as a valorization method for five typical e-waste resins: PSM, DFR, WPCB, SW, and F. Using TG-MS and TG-FTIR techniques, non-isothermal kinetic modeling was performed under a CO₂ atmosphere to determine activation energies and reaction mechanisms. The findings offer molecular-level insights into pollution control during e-waste gasification and establish a theoretical basis for process optimization guided by gasification kinetics, highlighting its engineering potential for sustainable waste treatment.

随着电子废弃物面临的挑战越来越大，本研究探索了CO 2辅助气化作为五种典型电子废弃物树脂（PSM， DFR， WPCB， SW和f）的气化方法。利用TG-MS和TG-FTIR技术，在CO 2气氛下进行了非等温动力学建模，以确定活化能和反应机理。该研究结果为电子废物气化过程中的污染控制提供了分子水平的见解，并为气化动力学指导下的过程优化奠定了理论基础，突出了其在可持续废物处理方面的工程潜力。

引用次数: 0

Density and excess molar enthalpy of (2-propanol + glyme) liquid mixtures. Application of the Flory model （2-丙醇+丙烯）液体混合物的密度和过量摩尔焓。Flory模型的应用

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2026-01-01 Epub Date: 2025-11-11 DOI: 10.1016/j.tca.2025.180179

João Victor Alves-Laurentino, Fatemeh Pazoki, Luis Felipe Sanz, Juan Antonio González, Fernando Hevia, Daniel Lozano-Martín

For glymes of general formula CH₃O(CH₂CH₂O)_uCH₃, with u = 1, 2, 3, 4, the densities of the (2-propanol + glyme) systems at temperatures ranging from (293.15 to 303.15) K and at pressure 0.1 MPa were determined using a DSA 5000 densimeter (from Anton Paar). The corresponding excess molar volumes were calculated from these density measurements. In addition, excess molar enthalpies at 298.15 K and 0.1 MPa were measured using a Tian-Calvet micro-calorimeter. The results show that alkanol–ether interactions are strong but do not contribute significantly to the excess molar enthalpy, as the values are large and positive, and comparable to those of (glyme + n-heptane) systems. The excess molar volumes are small or even negative (in the case of the mixture with u = 4), indicating that they are mainly governed by structural effects. Mixtures with 1-propanol or 2-propanol behave similarly, although interactions between unlike molecules become slightly stronger when 1-propanol is involved. On the other hand, effects related to alcohol self-association play a decisive role in the thermodynamic properties when glymes are replaced by di-n-propyl ether. This is supported by the application of the Flory model, which shows that orientational effects are weak in the studied glyme-containing mixtures but become significantly stronger when di-n-propyl ether is considered.

对于通式ch30 (CH2CH2O)uCH3的glyme， u = 1,2,3,4，在（293.15 ~ 303.15）K温度和0.1 MPa压力下，使用Anton Paar的DSA 5000密度计测定了（2-丙醇+ glyme）体系的密度。相应的过量摩尔体积是由这些密度测量计算出来的。此外，用Tian-Calvet微量热计测量了298.15 K和0.1 MPa下的过量摩尔焓。结果表明，烷醇-醚相互作用很强，但对过量摩尔焓没有显著贡献，因为其值很大且为正，与（甘醚+正庚烷）体系相当。过量摩尔体积很小甚至为负（在u = 4的混合物中），表明它们主要受结构效应的支配。与1-丙醇或2-丙醇的混合物表现相似，尽管当1-丙醇参与时，不同分子之间的相互作用会稍微强一些。另一方面，当甘烷被二正丙醚取代时，与醇自缔合有关的影响对热力学性质起决定性作用。Flory模型的应用支持了这一点，该模型表明，在所研究的含甘醚混合物中，取向效应很弱，但当考虑二正丙醚时，取向效应明显增强。

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引用次数: 0

Process hazard evaluation and exothermic mechanism study of nitrocellulose denitration 硝化纤维素脱硝工艺危害评价及放热机理研究

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2026-01-01 Epub Date: 2025-11-17 DOI: 10.1016/j.tca.2025.180183

Si-yu Zhong , Yu-nong Liu , Ya-jun Ding , Shi-ying Li

The denitration process of waste nitrocellulose (NC) using hydrazine hydrate presents potential thermal risks. This study systematically evaluated the process safety through Simultaneous Thermal Analysis, reaction calorimetry coupled with in situ Raman spectroscopy, ARC, and DFT calculations. Results indicated a significant temperature-dependent increase in heat release. Under adiabatic conditions starting at 85 °C, the MTSR reached 124.69 °C, exceeding the boiling point of hydrazine hydrate (113.5 °C) and suggesting a risk of boiling and ejection. Kinetic analysis yielded an apparent activation energy of 157.8 kJ/mol, confirming that the reaction is controlled by chemical steps. Real-time Raman monitoring, combined with DFT calculations, revealed the key exothermic pathway involving an unstable nitrohydrazine intermediate and the formation of nitrite. Finally, based on ΔT_ad and TMR_ad, risk matrix assessment classified the process risk as Level Ⅰ. This study identifies the critical temperature threshold for safe operation and provides a crucial theoretical basis and important safety guidance for industrial denitrification processes.

利用水合肼对废硝基纤维素进行脱硝具有潜在的热风险。本研究通过同步热分析、反应量热法、原位拉曼光谱、ARC和DFT计算系统地评估了工艺安全性。结果表明，热量释放明显依赖于温度的增加。在85℃开始的绝热条件下，MTSR达到124.69℃，超过水合肼的沸点113.5℃，存在沸腾和喷射的危险。动力学分析得到表观活化能为157.8 kJ/mol，证实了该反应是由化学步骤控制的。实时拉曼监测结合DFT计算，揭示了涉及不稳定硝基肼中间体和亚硝酸盐形成的关键放热途径。最后，基于ΔTad和TMRad进行风险矩阵评价，将过程风险划分为Ⅰ级。该研究确定了安全运行的临界温度阈值，为工业脱硝工艺提供了重要的理论依据和重要的安全指导。

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引用次数: 0

Experimental study of latent thermal energy storage with shape stabilized binary KAl(SO4)2·12H2O-MgSO4·7H2O hydrated salt material for Carnot batteries 卡诺电池用形状稳定二元KAl(SO4)2·12H2O-MgSO4·7H2O水合盐材料的潜热储能实验研究

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2026-01-01 Epub Date: 2025-11-28 DOI: 10.1016/j.tca.2025.180194

Zhuanying Hang , Yan Wang , Jianan Tao , Jingchen Zhang

Carnot battery system, particularly the Organic Rankine Cycle-based system, is an attractive energy storage solution for developing the future carbon-neutral energy system by utilizing low-grade heat (e.g., solar heat). As a cost-effective phase change material (PCM), aluminum potassium sulfate dodecahydrate (KAl(SO₄)₂·12H₂O) offers large heat capacity during melting/solidification at medium-low temperature, which holds a promising prospect in thermal energy storage system in Carnot Batteries. KAl(SO₄)₂·12H₂O is also one of the few types of hydrated salts without phase separation issue. In this study, binary inorganic hydrated salt mixtures of KAl(SO₄)₂·12H₂O and magnesium sulfate heptahydrate (MgSO₄·7H₂O) with various mass ratios were developed and prepared as a novel energy storage material at medium-low temperatures. The sample with a 6:4 mass ratio (KAl(SO₄)₂·12H₂O:MgSO₄·7H₂O) exhibited a phase-change enthalpy of 181.3 kJ/kg. Optimized mixture was impregnated into expanded graphite (EG) to form shape-stable composites. Results showed that even minimal EG loading prevented PCM leakage (leakage rate < 3%) and enhanced thermal conductivity (up to 5.23 W/(m·K)). The composite containing 8wt% EG exhibited a phase-change enthalpy of 175.7 kJ/kg, enabling rapid heat transfer. Thermal-cycling tests confirmed excellent reliability with negligible enthalpy loss. These properties made the composites highly suitable for thermal storage in Carnot batteries.

卡诺电池系统，特别是基于有机朗肯循环的系统，是一种有吸引力的能量存储解决方案，可以通过利用低品位的热量（例如太阳能热）来开发未来的碳中性能源系统。十二水合硫酸铝钾（KAl(SO4)2·12H2O）是一种经济高效的相变材料（PCM），在中低温熔融/凝固过程中具有较大的热容量，在卡诺电池蓄热系统中具有广阔的应用前景。KAl(SO4)2·12H2O也是为数不多的不存在相分离问题的水合盐。本研究研制了不同质量比的KAl(SO4)2·12H2O和七水硫酸镁（MgSO4·7H2O）二元无机水合盐混合物，并在中低温条件下制备了新型储能材料。质量比为6:4 （KAl（SO₄）₂·12H₂O:MgSO₄·7H₂O）的样品的相变焓为181.3 kJ/kg。将优化后的混合物浸渍在膨胀石墨（EG）中，形成形状稳定的复合材料。结果表明，即使最小的EG负载也可以防止PCM泄漏（泄漏率<； 3%）并增强热导率（高达5.23 W/(m·K)）。含8wt% EG的复合材料的相变焓为175.7 kJ/kg，可以实现快速传热。热循环试验证实了极好的可靠性，焓损失可以忽略不计。这些特性使得复合材料非常适合卡诺电池的储热。

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引用次数: 0

Deconvolution of superimposing reaction signals from DSC curves in selected Al-Mg-Si-(Cu) alloys by mean-field modeling and HEXRD 用平均场模型和HEXRD对Al-Mg-Si-(Cu)合金DSC曲线的叠加反应信号进行反卷积

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2026-01-01 Epub Date: 2025-11-17 DOI: 10.1016/j.tca.2025.180181

Robert Kahlenberg , Georg Falkinger , Roman Schuster , Bernhard Miesenberger , Nicolás García Arango , Emad Maawad , Erwin Povoden-Karadeniz , Benjamin Milkereit , Ernst Kozeschnik

The present work describes a systematic approach to improve mean-field simulations of dissolution and precipitation of precipitates from the late stages in the precipitation sequence in AlMgSiCu alloys for processing simulations. In addition to metastable precipitates, it considers the evolution of two populations (coarse and fine) of the thermodynamically stable phases in EN AW-6061 and EN AW-6016, β-Mg₂Si and Si respectively. The setup is based on two previous publications using heterogeneous nucleation site energies and their distribution. The simulations are calibrated using data from continuous cooling and heating experiments obtained with differential scanning calorimetry (DSC) and high-energy X-ray diffraction (HEXRD). We show that mean-field simulations combined with DSC and HEXRD can provide valuable information to eliminate uncertainties related to, for instance, the thermodynamic description of metastable precipitates. The method described in this paper also delivers very reasonable results for the evolution of the individual phase fractions. It potentially facilitates the assessment of the influence of different types of nucleation sites and their densities.

本工作描述了一种系统的方法来改进AlMgSiCu合金中析出序列后期析出相的溶解和析出的平均场模拟。除了亚稳相外，还考虑了EN AW-6061和EN AW-6016中热稳定相（β-Mg2Si和Si）的粗、细两族的演化。该设置是基于以前的两个出版物使用非均相成核位能和它们的分布。利用差示扫描量热法（DSC）和高能x射线衍射（HEXRD）获得的连续冷却和加热实验数据对模拟进行了校准。我们表明，结合DSC和HEXRD的平均场模拟可以提供有价值的信息，以消除与亚稳沉淀的热力学描述有关的不确定性。本文所描述的方法对于单个相分数的演化也提供了非常合理的结果。它可能有助于评估不同类型的成核位置及其密度的影响。

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引用次数: 0

Comparative analysis on thermal characteristics and microstructures of mining flame-retardant conveyor belts during pyrolysis and combustion 矿用阻燃输送带热解与燃烧过程热特性及微观结构对比分析

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2026-01-01 Epub Date: 2025-11-30 DOI: 10.1016/j.tca.2025.180196

Wei-Le Chen , Jun Deng , Yin Deng , Lan Yin , Cai-Ping Wang , Xia-Dan Duan , Hai-fei Lin

Mining flame-retardant conveyor belts (FRCBs) is a crucial bridge transporting coal in mine, but the occurrence of FRCB fires has seriously affected the safety transportation and mining of coal. To investigate their pyrolysis and combustion characteristics, FRCBs for polyvinyl chloride (PVC) and polyvinyl chloride gum elastic (PVG) were selected, and simultaneous thermal analysis-Fourier transform infrared spectroscopy was adopted to measure their pyrolysis and combustion characteristics, including mass loss characteristics, heat release properties, and gaseous products. Apparent activation energy was received by Kissinger-Akahira-Sunose method. The results indicated that, during combustion, FRCB for PVC and PVG experienced three and two weightlessness stages, respectively. and main functional groups of FRCB for PVC were HCl, chlorinated hydrocarbons, CO₂, and aromatic compounds, while FRCB for PVG generated additional gaseous products for cyanate gas. Meanwhile, the average apparent activation energy of FRCBs for PVG was 144.3 kJ·mol^-1 in the first stage of combustion, which was higher than that for PVC at 125.6 kJ·mol^-1. During pyrolysis, the FRCBs for PVG and PVC experienced two weightlessness stages, the FRCBs for PVC generated the additional CH gas and ester compounds, and PVG also produced ester compounds without cyanate gas. Moreover, their heat releases during pyrolysis were lower than that during combustion. while FRCB for PVG generated additional gaseous products for cyanate gas. The average apparent activation energy of FRCBs for PVG was 162.0 kJ·mol^-1 In the first stage of pyrolysis, which was higher than that for PVC at 143.3 kJ·mol^-1. These findings confirmed that PVG had superior flame retardancy compared to PVC. The research results provide a theoretical basis for determining key criteria in early intelligent warning.

矿用阻燃输送带是煤矿运输煤炭的重要桥梁，但阻燃输送带火灾的发生严重影响了煤炭的安全运输和开采。为了研究其热解和燃烧特性，选择聚氯乙烯（PVC）和聚氯乙烯胶弹性（PVG）的frcb，采用同步热分析-傅里叶变换红外光谱法测量其热解和燃烧特性，包括失重特性、放热特性和气态产物。用Kissinger-Akahira-Sunose法得到表观活化能。结果表明，在燃烧过程中，PVC和PVG的FRCB分别经历了3次和2次失重阶段。PVC的FRCB主要官能团为HCl、氯化烃、CO2和芳香族化合物，而PVG的FRCB产生的气态产物为氰酸盐气体。同时，frcb在燃烧第一阶段对PVG的平均表观活化能为144.3 kJ·mol-1，高于PVC的125.6 kJ·mol-1。在热解过程中，PVG和PVC的frcb经历了两个失重阶段，PVC的frcb产生了额外的CH气体和酯类化合物，PVG也产生了不含氰酸盐气体的酯类化合物。热解放出的热量也比燃烧放出的少。而用于PVG的FRCB则产生了额外的氰酸盐气体产物。在热解第一阶段，PVG的frcb平均表观活化能为162.0 kJ·mol-1，高于PVC的143.3 kJ·mol-1。这些发现证实了PVG与PVC相比具有更好的阻燃性。研究结果为智能预警关键准则的确定提供了理论依据。

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引用次数: 0

Valorization of petroleum slack wax for sustainable phase change materials with enhanced thermal energy storage 可持续性相变材料中石油松弛蜡的增值研究

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2026-01-01 Epub Date: 2025-12-02 DOI: 10.1016/j.tca.2025.180198

Abdel Illah Nabil Korti, Djahida Mahmoudi

This study valorizes slack wax, a petroleum refining byproduct, as a sustainable additive for paraffin-based phase change materials (PCMs). The limited heat storage of paraffin and the high cost of nanoscale additives hinder their application. We characterize composites using a refined T-History methodology, augmented by H-history analysis and polynomial interpolation for enhanced accuracy. Incorporating 20 % slack wax increases latent heat by 21 % (190–230 kJ/kg) while maintaining melting point stability (±0.2 °C). The composite demonstrates a sharper phase transition and excellent cycling stability (<1 % degradation after 15 cycles). Cross-validation of the Y- and H-methods revealed a minimal deviation in latent heat of <2 %, confirming the robustness of our measurements. Although thermal conductivity decreases by 17 %, this is offset by a 90 % cost reduction compared to nano-enhanced PCMs. The waste valorization benefits and high energy density make this material ideal for applications prioritizing storage capacity over rapid discharge, such as solar thermal storage and passive building temperature control. This approach provides a sustainable and economically viable pathway for large-scale PCM production, successfully repurposing industrial waste to advance thermal energy storage.

本研究对石油炼制副产物松弛蜡作为石蜡基相变材料（PCMs）的可持续添加剂进行了评价。石蜡的储热能力有限和纳米添加剂的高成本阻碍了它们的应用。我们使用改进的T-History方法来表征复合材料，并通过H-history分析和多项式插值来增强精度。加入20%的废蜡可增加21%的潜热（190-230 kJ/kg），同时保持熔点稳定性（±0.2°C）。复合材料表现出更明显的相变和优异的循环稳定性（循环15次后降解<； 1%）。Y-和h -方法的交叉验证显示潜热的最小偏差为<； 2%，证实了我们测量的稳健性。虽然导热系数降低了17%，但与纳米增强型PCMs相比，成本降低了90%。废物增值效益和高能量密度使这种材料非常适合优先考虑存储容量而不是快速放电的应用，例如太阳能蓄热和被动式建筑温度控制。这种方法为大规模PCM生产提供了一种可持续和经济可行的途径，成功地重新利用工业废物来推进热能储存。

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引用次数: 0

Study on the transfer behavior of key components and mainstream aerosol release characteristics from a novel hybrid tobacco product 一种新型杂交烟草制品关键组分转移行为及主流气溶胶释放特性研究

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2026-01-01 Epub Date: 2025-11-17 DOI: 10.1016/j.tca.2025.180182

Zhonghua Xiao , Dian Li , Qifeng Shen , Huaquan Sheng , Yihui Zhang , Yihan Gao , Naiping Gao

Amid growing health concerns regarding novel tobacco products, a hybrid device integrating electronic cigarette (EC) and heated tobacco product (HTP) technologies was developed to enable standalone or composite smoking. Comprehensive analysis revealed composite smoking increased total aerosol mass by 32.55 mg versus standalone EC and 9.37 mg versus standalone HTP, while elevating gaseous phase proportion. Particle number concentration rose 7.80 % with 18.39 % larger count median diameter versus HTP alone, and 315.83 % higher concentration with 15.34 % smaller diameter versus EC alone. Compared to standalone HTP, composite smoking demonstrated a 1.42 mg reduction in nicotine release and a 9.42 % decrease in residual key components. An "adsorption-thermal desorption" hypothetical mechanism is proposed to interpret these experimental findings. The results demonstrate that the composite smoking mode integrating electronic cigarettes and heated tobacco products in series can effectively enhance volatile component release while simultaneously reducing nicotine delivery.

在对新型烟草产品日益增长的健康担忧中，开发了一种集成电子烟（EC）和加热烟草产品（HTP）技术的混合设备，以实现独立或复合吸烟。综合分析表明，复合吸烟使气溶胶总质量比单独吸烟增加32.55 mg，比单独吸烟增加9.37 mg，同时提高了气相比例。颗粒数浓度比HTP单独增加7.80%，中位直径增加18.39%；颗粒数浓度比EC单独增加315.83%，中位直径减少15.34%。与单独使用HTP相比，复合吸烟显示尼古丁释放减少了1.42毫克，剩余关键成分减少了9.42%。提出了一种“吸附-热解吸”的假设机制来解释这些实验结果。结果表明，将电子烟与加热烟草制品串联在一起的复合吸烟方式可以有效地促进挥发性成分的释放，同时减少尼古丁的释放。

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引用次数: 0

Turning pan-sensor contact variability into a calibration tool for Sub-1% accuracy in heat capacity measurements with disk-type DSC 将泛传感器接触变异性转变为一种校准工具，用于低于1%的热容量测量精度

IF 3.5 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2026-01-01 Epub Date: 2025-11-20 DOI: 10.1016/j.tca.2025.180192

Yahya Rharbi, Frédéric Hugenell

The accuracy of absolute heat capacity (c_p) measurements in disk-type differential scanning calorimetry (DSC) has been perennially compromised by a fundamental yet unresolved issue: the poor reproducibility of pan-sensor thermal contact resistance (PS-TCR) upon manual repositioning. This systematic error, frequently treated as random noise, routinely introduces significant uncertainties that limit the reliability of c_p data, especially for small samples.

This work introduces a methodological advancement to overcome this limitation. We demonstrate that the isothermal heat flow (Q̇_iso), a readily measurable parameter in step-scan protocols, serves as a highly sensitive and quantitative signature of pan-positioning artifacts. By establishing a robust linear correlation between Q̇_iso and the integrated enthalpy signal (Q_s), we develop a novel correction procedure that effectively isolates and subtracts the positioning-dependent error component.

This strategy, validated experimentally and supported by a refined thermal model, systematically reduces c_p measurement uncertainty to below 1 % for sample masses as low as 5 mg, a level of precision previously unattainable in conventional disk-type DSCs without specialized equipment. Crucially, this approach requires no hardware modifications, relying solely on software-based post-processing of existing step-scan data. Our findings provide a practical and universally applicable solution to a decades-old problem, finally enabling high-accuracy c_p determination on standard DSC instruments and democratizing precision for the broader materials science community.

圆盘式差示扫描量热法（DSC）中绝对热容（cp）测量的准确性一直受到一个根本的尚未解决的问题的影响：手动重新定位后pan-sensor热接触电阻（PS-TCR）的再现性差。这种系统误差通常被视为随机噪声，通常会引入显著的不确定性，从而限制cp数据的可靠性，特别是对于小样本而言。这项工作引入了一种方法上的进步来克服这一限制。我们证明等温热流（Q o iso）是步进扫描协议中易于测量的参数，可作为泛定位伪像的高灵敏度和定量特征。通过建立Q / iso与积分焓信号（Qs）之间的鲁棒线性相关性，我们开发了一种新的校正程序，可以有效地分离和减去与位置相关的误差分量。该策略经过实验验证，并得到了精细热模型的支持，系统地将样品质量低至5mg的cp测量不确定度降低到1%以下，这是以前在没有专门设备的传统磁盘型dsc中无法达到的精度水平。至关重要的是，这种方法不需要硬件修改，仅依赖于基于软件的现有步进扫描数据的后处理。我们的研究结果为几十年前的问题提供了一个实用且普遍适用的解决方案，最终实现了在标准DSC仪器上的高精度cp测定，并使更广泛的材料科学界的精度民主化。

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引用次数: 0