Chemical Thermodynamics and Thermal Analysis最新文献_第4页

Synergistic effect of kerosene, alumina nanoparticles, and surfactants on the rheological behavior of heavy crude oil 煤油、氧化铝纳米颗粒和表面活性剂对重质原油流变行为的协同效应

Chemical Thermodynamics and Thermal Analysis

Pub Date : 2025-10-01 DOI: 10.1016/j.ctta.2025.100244

Luay Ahmed Khamees , Ghassan H. Abdul-Majeed , Ayad A. Alhaleem

The rheological enhancement of heavy crude oils remains a critical challenge for the petroleum industry due to their inherently high viscosity and density. This study evaluates the performance of kerosene-based nanofluid systems in improving the flow behavior of heavy crude oil from the East Baghdad field. Five formulations were investigated: surfactant alone (SDBS), alumina (Al₂O₃) nanoparticles, kerosene, a binary blend of kerosene and nanoparticles, and a ternary nanofluid comprising kerosene, alumina nanoparticles, and SDBS. TGA, XRD, and AFM were used to determine the thermal stability, crystallinity and surface morphology of the alumina nanoparticles. Experiments were upgraded at a temperature of 20–75 °C and the ultrasonic-assisted dispersion treatment was done over a period of 15–60 min. The ternary nanofluid was the most tested system with the highest performance with a maximum viscosity reduction of 80 % and an increase in API gravity of 50 %. Such refinements show there is a great improvement in flowability and density properties of the crude. The findings demonstrate high-order synergistic relationships among surfactant, nanoparticles, and solvent under the stimulation of ultrasound, which provides a scalable and energy-efficient route towards heavy crude oil upgrading.

由于重质原油固有的高粘度和高密度，其流变性能的提高一直是石油工业面临的一个严峻挑战。本研究评估了煤油基纳米流体系统在改善东巴格达油田重质原油流动特性方面的性能。研究了五种配方：单表面活性剂（SDBS）、氧化铝（Al₂O₃）纳米颗粒、煤油、煤油和纳米颗粒的二元混合物，以及由煤油、氧化铝纳米颗粒和SDBS组成的三元纳米流体。利用TGA、XRD、AFM等表征了纳米氧化铝的热稳定性、结晶度和表面形貌。实验在20-75℃的温度下进行升级，超声辅助分散处理时间为15-60 min。三元纳米流体是测试次数最多、性能最好的体系，最大粘度降低了80%，原料药比重增加了50%。这些改进表明原油的流动性和密度性能有很大的改善。研究结果表明，在超声刺激下，表面活性剂、纳米颗粒和溶剂之间存在高阶协同关系，为重质原油提质提供了一条可扩展且节能的途径。

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引用次数: 0

A review on performance of refrigeration system using nano-refrigerant & nano-lubricant 纳米制冷剂和纳米润滑剂制冷系统性能研究进展

Chemical Thermodynamics and Thermal Analysis

Pub Date : 2025-10-01 DOI: 10.1016/j.ctta.2025.100222

Niraj N. Raja , Avinash D. Khanderao

The increasing demand for energy-efficient and eco-friendly refrigeration technologies has spurred research into nanofluids. Nano-refrigerant & Nano-lubricant, as advanced nanofluids are revolutionizing the design and analysis of thermal engineering systems by enhancing thermo-physical and heat transfer properties of working fluids thereby improving the overall system performance. These nanofluids, formed by suspending nanoparticles in base fluids, can be directly used in vapor compression refrigeration systems without any modifications significantly boosting heat transfer in refrigeration and air-conditioning devices. The heat transfer performance of any thermal engineering system depends on critical properties such as the thermal conductivity and viscosity of the working fluid, which are ultimately influenced by the concentration and stability of nanoparticles in the base fluid.

This paper provides a comprehensive review of recent research on the performance of refrigeration and air conditioning systems through the application of various nano-refrigerants and nano-lubricants. It focuses on cooling capacity, coefficient of performance, and overall energy efficiency. Challenges such as nanoparticle stability, optimal concentration and system compatibility issues are also discussed. This study aims to promote energy-efficient and environmentally friendly nano-refrigerants & nano-lubricants which hold significant promise for the next generation of sustainable refrigeration & air-conditioning systems.

对节能环保制冷技术日益增长的需求刺激了对纳米流体的研究。纳米制冷剂和纳米润滑剂作为先进的纳米流体，通过增强工作流体的热物理和传热特性，从而提高整个系统的性能，正在彻底改变热工程系统的设计和分析。这些纳米流体由悬浮在基础流体中的纳米颗粒形成，可以直接用于蒸汽压缩制冷系统，而无需任何修改，显著提高制冷和空调设备的传热。任何热工系统的传热性能都取决于工作流体的热导率和粘度等关键性能，而这些性能最终受到基液中纳米颗粒的浓度和稳定性的影响。本文综述了近年来各种纳米制冷剂和纳米润滑剂在制冷和空调系统性能方面的研究进展。它侧重于冷却能力、性能系数和整体能源效率。此外，还讨论了纳米颗粒稳定性、最佳浓度和系统相容性等问题。本研究旨在推广节能环保的纳米制冷剂和纳米润滑剂，这对下一代可持续制冷空调系统具有重要的前景。

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引用次数: 0

Thermoplastic analysis of phases of cryoprotective solutions 低温保护溶液相的热塑性分析

Chemical Thermodynamics and Thermal Analysis

Pub Date : 2025-10-01 DOI: 10.1016/j.ctta.2025.100230

O.I. Osetsky, T.M. Gurina

A method for studying phases of frozen solutions by thermoplastic deformation has been tested. High efficiency of this approach has been demonstrated for polycrystalline matrices with liquid-phase layers between crystals. The exponential dependence of solution viscosity on temperature in these layers ensures high sensitivity of thermoplastic deformation to thermal effects associated with phase transformations in liquid fractions. The obtained data allow elucidating phase compositions of cryoprotective solutions around their vitrification temperatures. They prove a possibility of the existence of cluster particles in cryoprotective solutions based on both ice microcrystals and microcrystals of a cryoprotectant. This fact determines the principles of constructing complete phase diagrams of cryoprotective solutions, including areas of cluster phases of these two types.

试验了一种用热塑性变形法研究冻结溶液相的方法。该方法对晶体间有液相层的多晶矩阵具有很高的效率。在这些层中，溶液粘度对温度的指数依赖性确保了热塑性变形对与液相相变相关的热效应的高灵敏度。所获得的数据允许阐明其玻璃化温度周围的冷冻保护溶液的相组成。他们证明了基于冰晶和低温保护剂微晶的低温保护溶液中存在团簇粒子的可能性。这一事实决定了构建冷冻保护溶液的完整相图的原则，包括这两种类型的簇相区域。

引用次数: 0

Adsorption energy 吸附能

Chemical Thermodynamics and Thermal Analysis

Pub Date : 2025-10-01 DOI: 10.1016/j.ctta.2025.100240

Miguel Gonzalo Arenas-Quevedo, Jesús Gracia-Fadrique, José Luis López-Cervantes

引用次数: 0

Synthesis of (PDAN/n-TiO2) composites by in-situ 1,8-diaminophthalene polymerization for the adsorptive removal of molybdate anions 原位聚合法制备（PDAN/n-TiO2）复合材料吸附去除钼酸盐阴离子

Chemical Thermodynamics and Thermal Analysis

Pub Date : 2025-10-01 DOI: 10.1016/j.ctta.2025.100235

Ali Mahvashian , Hossein Sid Kalal , Zahra Shiri-Yekta , Mohammad Taghiof

In this study, nano-titanium dioxide(n-TiO₂) modified with poly(1,8-diaminophthalene)(PDAN) were employed for the removal of Mo(VI) ions from aqueous solutions. The synthesized adsorbent was characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and Thermal gravimetric analysis (TGA). Key parameters influencing the adsorption performance in the batch process, including pH, adsorbent dosage, temperature, and initial metal ion concentration, were investigated at different temperatures (26, 36, and 45 °C). According to the results, the optimal conditions were determined as follows: pH = 3.5, adsorbent dosage = 0.04 g, initial concentration = 4 mg/L, temperature = 26 °C, agitation speed = 180 rpm, and contact time = 5 h. Under these conditions, the maximum adsorption capacity was found to be 4.5369 mg/g. Various isotherms and error models were employed to identify the best-fitting isotherm model and to estimate the corresponding parameters. Among them, the Radke–Prausnitz isotherm model showed the highest agreement with the experimental data. The adsorption kinetics followed a pseudo-second-order (PSO) model. Thermodynamic analysis confirmed that the adsorption of Mo(VI) ions was spontaneous and endothermic. Furthermore, the effect of interfering ions under optimal conditions was studied. Desorption experiments at different concentrations were also conducted to evaluate the reusability of the adsorbent. Among the tested desorbing agents, ammonium acetate (CH₃COONH₄) demonstrated the highest desorption efficiency of approximately 36 % at an optimal concentration of 0.5 M.

本研究采用聚（1,8-二氨基苯）（PDAN）修饰的纳米二氧化钛（n-TiO2）去除水溶液中的Mo（VI）离子。采用x射线衍射（XRD）、傅里叶变换红外（FTIR）、扫描电镜（SEM）、x射线能谱（EDS）和热重分析（TGA）对合成的吸附剂进行了表征。在不同温度（26℃、36℃和45℃）下，考察了pH、吸附剂用量、温度和初始金属离子浓度等影响间歇吸附性能的关键参数。结果表明，最佳吸附条件为：pH = 3.5，吸附剂用量= 0.04 g，初始浓度= 4 mg/L，温度= 26℃，搅拌速度= 180 rpm，接触时间= 5 h，在此条件下，吸附量最大可达4.5369 mg/g。利用不同的等温线和误差模型来确定最适合的等温线模型，并估计相应的参数。其中，Radke-Prausnitz等温线模型与实验数据的吻合度最高。吸附动力学符合准二阶（PSO）模型。热力学分析证实了Mo（VI）离子的吸附是自发的、吸热的。此外，还研究了在最佳条件下干扰离子的影响。还进行了不同浓度的解吸实验，以评价吸附剂的可重复使用性。其中乙酸铵（CH₃COONH₄）在最佳浓度为0.5 M时的解吸效率最高，约为36%。

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引用次数: 0

A study on the thermo-physical properties of EG/water-based nanofluids containing low and high concentrations of MgO nanoparticles 含低、高浓度氧化镁纳米颗粒的EG/水基纳米流体热物性研究

Chemical Thermodynamics and Thermal Analysis

Pub Date : 2025-10-01 DOI: 10.1016/j.ctta.2025.100228

Nurul Izzati Akmal Muhamed Rafaizul , Mohd Afzanizam Mohd Rosli , Mohd Nurazzi Norizan , Noor Aisyah Ahmad Shah , Keat Khim Ong , Intan Juliana Shamsudin , Norherdawati Kasim , Mohd Haizal Mohd Husin , Norli Abdullah

Nanofluids have gained significant attention for their enhanced thermophysical properties, making them suitable for high-performance cooling applications. This study investigates the thermal conductivity and stability of ethylene glycol (EG)/water-based nanofluids containing magnesium oxide (MgO) nanoparticles at low (0.02, 0.04, and 0.06 wt.%) and high (0.2, 0.4, and 0.6 wt.%) concentrations. MgO nanoparticles were synthesized via the sol-gel method and characterized using XRD, FTIR, SEM, and EDS analysis. Nanofluids were prepared using a two-step method with polyvinylpyrrolidone (PVP) as a stabilizing surfactant. UV–vis spectroscopy and visual observation were used to assess the colloidal stability over a 30-day period, while thermal conductivity and viscosity were measured at varying temperatures (25 °C, 40 °C, and 60 °C). The results demonstrate that thermal conductivity increased with both nanoparticle concentration and temperature, with a maximum enhancement of 40.51% observed at 0.6 wt.% and 60 °C. However, stability declined at higher concentrations, with notable sedimentation at and beyond 0.4 wt.%. The 0.2 wt.% sample exhibited the best balance between thermal enhancement and long-term stability. These findings suggest that MgO-EG/water nanofluids in the range of 0.2–0.4 wt.% offer optimal performance for thermal applications such as automotive coolants and photovoltaic thermal systems.

纳米流体因其增强的热物理特性而获得了极大的关注，使其适用于高性能冷却应用。本研究考察了含氧化镁纳米颗粒的乙二醇/水基纳米流体在低（0.02、0.04和0.06 wt.%）和高（0.2、0.4和0.6 wt.%）浓度下的导热性和稳定性。采用溶胶-凝胶法制备了MgO纳米颗粒，并利用XRD、FTIR、SEM和EDS对其进行了表征。以聚乙烯吡咯烷酮（PVP）为稳定表面活性剂，采用两步法制备纳米流体。使用紫外可见光谱和目视观察来评估30天内的胶体稳定性，同时在不同温度（25°C， 40°C和60°C）下测量热导率和粘度。结果表明，导热系数随纳米颗粒浓度和温度的增加而增加，在0.6 wt.%和60°C时，导热系数最大增强40.51%。然而，在较高的浓度下，稳定性下降，在0.4 wt.%及以上有明显的沉降。0.2 wt.%的样品在热增强和长期稳定性之间表现出最好的平衡。这些发现表明，在0.2-0.4 wt.%范围内的氧化镁- eg /水纳米流体为汽车冷却剂和光伏热系统等热应用提供了最佳性能。

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引用次数: 0

Temperature-dependent interaction between niacin/D-panthenol in aqueous α-lipoic acid: Physicochemical and spectroscopic analysis 烟酸/ d -泛醇在α-硫辛酸水溶液中的温度依赖性相互作用：理化和光谱分析

Chemical Thermodynamics and Thermal Analysis

Pub Date : 2025-10-01 DOI: 10.1016/j.ctta.2025.100234

Rupavalli Talabattula , Nabaparna Chakraborty , Kailash Chandra Juglan

Volumetric and acoustic characteristics of binary (niacin/d-panthenol + water) and ternary (niacin/d-panthenol + α-lipoic acid + water) systems were analysed to understand solute–solvent and solute–solute interactions. Thermodynamic and acoustic properties, including apparent and partial molar volumes, isentropic compressibility, transfer volumes, and interaction ncoefficients, were measured over the temperature range 288.15–318.15 K and at various α-lipoic acid concentrations. The structure-making and structure-breaking tendencies of these systems were assessed using derivative quantities, such as apparent molar expansibility and its temperature dependence. Additional FTIR spectroscopy confirmed hydrogen bonding and revealed temperature-dependent reconfiguration of solvation structures. The combined volumetric, acoustic, and spectroscopic analyses provided a molecular-level understanding of solvation dynamics in vitamin acid mixtures. These findings enhance our understanding of intermolecular interactions and support the development of sustainable co-solvent systems in pharmaceutical and cosmetic formulations, in line with the UN Sustainable Development Goals (SDGs).

分析了二元体系（烟酸/d-泛醇+水）和三元体系（烟酸/d-泛醇+ α-硫辛酸+水）的体积和声学特性，以了解溶质-溶剂和溶质-溶质相互作用。在288.15 ~ 318.15 K的温度范围和不同α-硫辛酸浓度下，测量了其热力学和声学性质，包括表观摩尔体积和偏摩尔体积、等熵压缩率、传递体积和相互作用系数。利用表观摩尔膨胀率及其温度依赖性等导数量评价了体系的结构形成和结构破坏倾向。另外的FTIR光谱证实了氢键，并揭示了温度依赖性的溶剂化结构重构。结合体积，声学和光谱分析提供了维生素酸混合物中溶剂化动力学的分子水平的理解。这些发现增强了我们对分子间相互作用的理解，并支持在药物和化妆品配方中开发可持续的共溶剂系统，符合联合国可持续发展目标（SDGs）。

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引用次数: 0

Removal of phenol from an aqueous solution using carbon from African potato (hypoxis hemerocallidea) waste 利用非洲马铃薯废料中的碳从水溶液中去除苯酚

Chemical Thermodynamics and Thermal Analysis

Pub Date : 2025-10-01 DOI: 10.1016/j.ctta.2025.100237

ND Shooto, PM Thabede

The concentration of phenol in industrial wastewater has reached alarming proportions, reaching up to 7000 mg/L in some regions. Yet, the permissible level of phenol in drinking water is 0.3 mg/L. This study developed three low-cost adsorbents for removing phenol from water. The adsorbents were synthesized from (i) carbon derived from African potato waste (CAP), (ii) activation of the carbon with phosphoric acid (ACAP), and (iii) carbon activation with sodium hydroxide (BCAP). The BET results showed that the activated adsorbents had a mesoporous structure. SEM images for CAP showed that the sample had a rough surface texture and wrinkles, while ACAP and BCAP had amorphous particles of different shapes and sizes with porous surfaces. Batch adsorption experiments showed that increasing the temperature of the system impaired the uptake of phenol for all adsorbents, indicating that the adsorption process was exothermic. The equilibrium data indicated that the adsorption fits the Langmuir model, with predicted maximum adsorption capacities of 14.76, 61.39 and 71.55 mg/g for CAP, ACAP and BCAP, respectively. In addition, CAP fits the PFO model, while ACAP and BCAP fit the PSO model. The maximum adsorption capacity was achieved at a solution pH of 6. The time-contact effect trends showed three phases: fast adsorption (5-20 min), slow adsorption (20-60 min) and equilibrium (60-120 min). The values of △G^o and △H^o were negative, indicating that the uptake of phenol on the adsorbents was spontaneous and the removal was exothermic. The △H^o value for CAP was -0.591 KJ/mol, indicating physisorption, while ACAP and BCAP were -86.66 and -50.22 KJ/mol, respectively, indicating chemisorption.

工业废水中苯酚的浓度已经达到了令人担忧的程度，有的地区甚至达到了7000 mg/L。然而，饮用水中苯酚的允许含量为0.3毫克/升。本研究开发了三种低成本的水中苯酚吸附剂。吸附剂是由(i)从非洲马铃薯废料中提取的碳（CAP），（ii）用磷酸（ACAP）活化碳，（iii）用氢氧化钠（BCAP）活化碳合成的。BET结果表明，活性吸附剂具有介孔结构。CAP的SEM图像显示，样品表面纹理粗糙，有褶皱，而ACAP和BCAP则有不同形状和大小的无定形颗粒，表面多孔。间歇式吸附实验表明，提高体系温度对各吸附剂对苯酚的吸附均有抑制作用，表明吸附过程为放热吸附。平衡数据表明，吸附符合Langmuir模型，CAP、ACAP和BCAP的最大吸附量分别为14.76、61.39和71.55 mg/g。另外，CAP适合PFO模型，ACAP和BCAP适合PSO模型。溶液pH为6时吸附量最大。时间接触效应趋势表现为快速吸附（5 ~ 20 min）、缓慢吸附（20 ~ 60 min）和平衡（60 ~ 120 min）三个阶段。△Go和△Ho值均为负值，说明苯酚在吸附剂上的吸附是自发的，脱除是放热的。CAP的△Ho值为-0.591 KJ/mol，为物理吸附，ACAP和BCAP的△Ho值分别为-86.66和-50.22 KJ/mol，为化学吸附。

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引用次数: 0

Formation and characterization of β-Cyclodextrin inclusion complexes with 1-Allyl -3 -Methyl dicyanamide ionic liquids β-环糊精与1-烯丙基-3 -甲基双氰酰胺离子液体包合物的形成与表征

Chemical Thermodynamics and Thermal Analysis

Pub Date : 2025-10-01 DOI: 10.1016/j.ctta.2025.100232

Z. Barhoumi , N. Amdouni , M. Hachicha , K. Kuperkar , O. Ghodbane , R. Besbes

This work presents a comprehensive study on the aggregation behaviour and inclusion complexation of 1-allyl-3-methylimidazolium dicyanamide ([Amim]DCA) with β-cyclodextrin (β-CD) in aqueous solutions. A multi-technique approach was used to elucidate the nature of the interactions, including conductivity, ultraviolet–visible (UV–VIS) spectroscopy, dynamic light scattering (DLS), and density and viscosity measurements. Conductivity decreased with increasing β-CD concentration, with a significant dip at 1 mM β-CD, indicating 1:1 host-guest stoichiometry. Thermodynamic parameters derived from density and viscosity data, such as apparent molar volume (V_φ), isentropic expansion coefficient (α_P) and activation energy for viscous flow (E_a), further confirmed the confinement of [Amim]DCA within β-CD. Job's plot analysis and binding constant calculations supported the preferential encapsulation of the DCA⁻ anion inside the β-CD cavity while the [Amim]⁺ cation remained solvated bulk water. FTIR spectroscopy corroborated this inclusion mechanism. DLS and zeta potential measurements showed an increase in particle size and a decrease in surface charge upon the addition of β-CD, consistent with the formation of stable host-guest aggregates. These findings enhance our understanding of the IL-cyclodextrin host-guest complex and support its potential applications in nanostructure engineering and drug delivery.

本文全面研究了1-烯丙基-3-甲基咪唑双氰酰胺（[Amim]DCA）与β-环糊精（β-CD）在水溶液中的聚集行为和包合作用。采用多技术方法来阐明相互作用的性质，包括电导率、紫外-可见（UV-VIS）光谱、动态光散射（DLS）、密度和粘度测量。随着β-CD浓度的增加，电导率下降，在1 mM β-CD时电导率显著下降，表明主客体化学计量为1:1。根据密度和粘度数据得出的热力学参数，如表观摩尔体积（Vφ）、等熵膨胀系数（αP）和粘性流动活化能（Ea），进一步证实了[Amim]DCA被限制在β-CD内。Job的图分析和结合常数计算支持了DCA−阴离子在β-CD腔内的优先包封，而[Amim] +阳离子仍然是溶剂化的体水。FTIR光谱证实了这种包合机制。DLS和zeta电位测量表明，加入β-CD后，颗粒大小增加，表面电荷减少，与形成稳定的主-客体聚集体一致。这些发现增强了我们对il -环糊精主客体复合物的理解，并支持其在纳米结构工程和药物传递方面的潜在应用。

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引用次数: 0

Thermophysical properties of blended absorbents for CO2 capture: NMDEA with alkanol (C1–C2) at 298.15 K to 318.15 K 二氧化碳捕获混合吸收剂的热物理性质：在298.15 K至318.15 K下，NMDEA与烷醇（C1-C2）

Chemical Thermodynamics and Thermal Analysis

Pub Date : 2025-10-01 DOI: 10.1016/j.ctta.2025.100243

Sweety Verma , Payal Bhagat , Manju Rani , Seungjun Baek , Juwon Min , Sanjeev Maken

<div><div>The purpose of this study is to investigate the thermophysical properties and molecular interactions of binary mixtures of N‒methyl diethanolamine (1) with alkanol (C<sub>1</sub>‒C<sub>2</sub>) (2) at <em>T</em> = 298.15 K to 318.15 K and at 0.1 MPa pressure, to gain insight into their structural behavior and intermolecular interactions. These properties would be employed in future studies for CO<sub>2</sub> absorption.</div><div>To achieve this, density (<span><math><mi>ρ</mi></math></span>), viscosity (<span><math><mi>η</mi></math></span>), speed of sound (<span><math><mi>u</mi></math></span>), and refractive index (<span><math><msub><mi>n</mi><mi>D</mi></msub></math></span>), of the mixtures were experimentally measured. Measured data were used to calculate excess molar volume (<span><math><msup><mrow><msub><mi>V</mi><mi>m</mi></msub></mrow><mi>E</mi></msup></math></span>), deviation in viscosity (<span><math><mrow><mstyle><mi>Δ</mi></mstyle><mi>η</mi></mrow></math></span>), deviation in the speed of sound (<span><math><mrow><mstyle><mi>Δ</mi></mstyle><mi>u</mi></mrow></math></span>), excess isentropic compressibility (<span><math><msup><mrow><msub><mi>κ</mi><mi>s</mi></msub></mrow><mi>E</mi></msup></math></span>), and deviation in refractive index (<span><math><mrow><mstyle><mi>Δ</mi></mstyle><msub><mi>n</mi><mi>D</mi></msub></mrow></math></span>), correlated with the RK equation. Partial (<span><math><msub><mover><mi>V</mi><mo>¯</mo></mover><mi>i</mi></msub></math></span>) and excess partial (<span><math><msubsup><mover><mi>V</mi><mo>¯</mo></mover><mi>i</mi><mi>E</mi></msubsup></math></span>) molar volumes were derived to assess molecular contributions. Additionally, theoretical predications of <span><math><msup><mrow><msub><mi>V</mi><mi>m</mi></msub></mrow><mi>E</mi></msup></math></span>, <span><math><mrow><mstyle><mi>Δ</mi></mstyle><mi>η</mi></mrow></math></span>, and <span><math><msup><mrow><msub><mi>κ</mi><mi>s</mi></msub></mrow><mi>E</mi></msup></math></span>values were performed using a Graph theoretical approach (GTA), and FTIR spectral data were analyzed to validate GTA predications and identify intermolecular interactions.</div><div>The results show that the mixtures are strongly influenced by H–bonding, dispersive, and cohesive forces, as well as molecular structure. Negative values of <span><math><msup><mrow><msub><mi>V</mi><mi>m</mi></msub></mrow><mi>E</mi></msup></math></span>, <span><math><mrow><mstyle><mi>Δ</mi></mstyle><mi>η</mi></mrow></math></span>, and <span><math><msup><mrow><msub><mi>κ</mi><mi>s</mi></msub></mrow><mi>E</mi></msup></math></span> values indicate strong attractive interactions and efficient packing, whereas positive<span><math><mrow><mstyle><mi>Δ</mi></mstyle><mi>u</mi></mrow></math></span> and <span><math><mrow><mstyle><mi>Δ</mi></mstyle><msub><mi>n</mi><mi>D</mi></msub></mrow></math></span> reflect enhanced structural ordering. Partial molar volume (<span><math><msub><mover><mi>V</mi><mo>¯</mo><

本研究的目的是研究n -甲基二乙醇胺(1)与烷醇（C1-C2）(2)二元混合物在温度为298.15 K ~ 318.15 K和0.1 MPa压力下的热物理性质和分子间相互作用，以了解其结构行为和分子间相互作用。这些特性将用于未来的二氧化碳吸收研究。为此，实验测量了混合物的密度（ρ）、粘度（η）、声速(u)和折射率（nD）。测量数据用于计算与RK方程相关的过量摩尔体积（VmE）、粘度偏差（Δη）、声速偏差（Δu）、过量等熵压缩率（κsE）和折射率偏差（ΔnD）。部分（V¯i）和超额部分（V¯iE）摩尔体积被导出来评估分子的贡献。此外，使用图形理论方法（GTA）对VmE、Δη和κ sev值进行理论预测，并分析FTIR光谱数据以验证GTA预测并识别分子间相互作用。结果表明，混合物受氢键、色散、黏结力以及分子结构的强烈影响。VmE、Δη和κsE值为负值表明吸引相互作用强，填充有效，而positiveΔu和ΔnD则表明结构有序增强。偏摩尔体积（V¯i）分析证实了异分子相互作用的优势。GTA预测与实验数据一致，FTIR光谱证实了氢键的存在。

引用次数: 0