Isothermal Calorimetry Methods Research Articles

Understanding the heat generation mechanisms and the interplay between joule heat and entropy effects as a function of state of charge in lithium-ion batteries

The thermal performance of lithium-ion battery cells is critical for ensuring their safe and reliable operation across various applications. In this study, we employed an isothermal calorimetry method to investigate the heat generation of commercial 18650 lithium-ion battery fresh cells during charge and discharge at different current rates, ranging from 0.05C to 0.5C, and across various temperatures: 20 °C, 30 °C, 40 °C, and 50 °C. Our findings revealed a direct correlation between heat generation and current rates, indicating that higher current rates lead to increased heat generation within the cells. Conversely, we observed that heat generation remained relatively stable as the temperature rose, suggesting that temperature changes within this range may not significantly impact the heat generation of fresh cells during typical operations. Furthermore, our study explored irreversible heat generation, which depends on the applied current and overpotential, using the galvanostatic intermittent titration technique at 0.05C–0.5C and 30 °C. Additionally, electrochemical impedance spectroscopy was performed on the same cells during charge and discharge at 20 °C, 30 °C, and 40 °C to analyze cell impedance. Our results indicated a consistent dependence of impedance on the state of charge and depth of discharge, with a significant increase in impedance observed at the end of the discharge process.

STUDY OF THE INFLUENCE OF MODIFIERS ON THE HYDRATION OF CEMENT BY THE METHOD OF ISOTHERMAL CALORIMETRY

The effect of modifiers on the hydration of cements was studied by isothermal calorimetry. Thermochemical experiments were carried out using a TAM III isothermal calorimeter (TA Instruments). For the TAM III calorimeter, a method was developed for conducting experiments on monitoring the thermal activity of solid-phase samples with the possibility of repeated use of steel ampoules with a volume of 20 ml. The processes of hydration of Portland cement grade CEM I 42.5B D0 LLC "Holcim Rus" without a modifier and with modifiers polycarboxylate type S (POLYPLAST LLC and «Glass Powder) were studied. Heat release thermograms were recorded, which showed good reproducibility of the results and their similarity with those available in the literature for similar studies carried out according to standard methods using a TAM AIR isothermal calorimeter (TA Instruments). This indicates the reliability of the obtained data and the possibility of using the method proposed in this article to study the processes of hydration of cements. The maximum heat release on the thermograms of samples with a polycarboxylate modifier is observed approximately 20 h after the start of heat release monitoring. Samples without the modifier and with the glass powder modifier show the maximum heat release approximately 10 h after the start of the experiment. Analysis of the results showed that the presence of modifiers leads to increased heat release during cement hydration in relation to its initial composition. Accordingly, it takes less time to complete hydration. However, it is also necessary to take into account the possible risks of violation of the technological modes of operation of the corresponding equipment due to excessive heat release during the hydration of modified cements. For citation: Usacheva T.R., Krainova A.A., Vinogradova L.A., Oganyan V.V., Kokurina G.N., Myshenkov M.S., Anufrikov Yu.A., Shasherina A.Yu., Adamtsevich A.O. Study of the influence of modifiers on the hydration of cement by the method of isothermal calorimetry. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 6. P. 88-93. DOI: 10.6060/ivkkt.20246706.6979.

Continuous cooling and isothermal solidification analysis of AlSi10Mg using differential fast scanning calorimetry

This study investigates the solidification process of individual micro-sized AlSi10Mg particles using continuous cooling and isothermal differential fast scanning calorimetry (DFSC) methods at a range of cooling rates (from 500 K/s to 50,000 K/s) and temperatures (from 562 °C to 502 °C). The solidification microstructure consists of fine α-Al dendrites and (α-Al + Si) eutectics. Both dendrite arm spacing and eutectic spacing decrease with increasing cooling rate, as well as decreasing solidification temperature. The continuous cooling treatment exhibits finer microstructures compared to those observed in the isothermal treatment in the similar solidification temperature range. Overall, this study highlights the effectiveness of the DFSC methods, along with microstructure characterization, in analyzing the solidification process of individual powder particles over a wide range of cooling rates and temperatures.

Layer-by-layer assembly of poly-l-lysine/hyaluronic acid protein reservoirs on poly(glycerol sebacate) surfaces

The modification of biomaterial surfaces has become increasingly relevant in the context of ongoing advancements in tissue engineering applications and the development of tissue-mimicking polymer materials. In this study, we investigated the layer-by-layer (LbL) deposition of polyelectrolyte multilayer protein reservoirs consisting of poly-l-lysine (PLL) and hyaluronic acid (HA) on the hydrophobic surface of poly(glycerol sebacate) (PGS) elastomer. Using the methods of isothermal titration calorimetry and surface plasmon resonance, we systematically investigated the interactions between the polyelectrolytes and evaluated the deposition process in real time, providing insight into the phenomena associated with film assembly. PLL/HA LbL films deposited on PGS showed an exceptional ability to incorporate bone morphogenetic protein-2 (BMP-2) compared to other growth factors tested, thus highlighting the potential of PLL/HA LbL films for osteoregenerative applications. The concentration of HA solution used for film assembly did not affect the thickness and topography of the (PLL/HA)10 films, but had a notable impact on the hydrophilicity of the PGS surface and the BMP-2 release kinetics. The release kinetics were successfully described using the Weibull model and hyperbolic tangent function, underscoring the potential of these less frequently used models to compare the protein release from LbL protein reservoirs.

State primary special standard of the unit of heat quantity in the fi eld of solution and reaction calorimetry GET 133-2023

The article shows the need to develop methods and tools for realization and transferring a unit of heat quantity in the fi eld of measuring small thermal effects of physical and chemical interactions by the method of isothermal titration calorimetry. The relevance of the work is due to the wide application of measuring instruments implementing this method and the lack of standardized metrological procedures and tools. To solve the problem of ensuring unity and traceability of measurements in this fi eld, VNIIM calorimetry laboratory conducted research to expand the functional and measuring capabilities of the State primary special standard of the unit of heat quantity in the fi eld of solution and reaction calorimetry GET 133-2012. In the course of work a reference titration microcalorimeter MKT was developed, investigated, and included in the GET 133-2012. Microcalorimeter MKT was designed to realize, store, and transfer a unit of heat quantity in the fi eld of measuring small thermal effects in liquid media. As a result of microcalorimeter studies, the capability of realizing and transferring a unit of heat quantity in a new range was confi rmed: from 100 to 5000 μJ with an expanded uncertainty from 1.2 to 8.6 %. The improved GET 133-2012 with an updated composition and new metrological characteristics was approved as the State primary special standard of the unit of heat quantity in the fi eld of solution and reaction calorimetry GET 133-2023. This lays the foundations for the creation of new metrological tools and procedures for transferring the unit of heat quantity in the fi eld of solution and reaction calorimetry.

Antioxidant efficiency and oxidizability of mayonnaise by oximetry and isothermal calorimetry

This study aimed to introduce a new method based on isothermal calorimetry (IC) for measuring the autoxidation rate in mayonnaise samples. Mayonnaise samples were prepared by homogenizing an aqueous phase, consisting of vinegar and egg yolk, with various oil phases, including sunflower, corn, extra virgin olive, grape seed, and apple seed oils at 60 °C. The rate of free radical formation (Ri) was controlled by adding AIBN (Ri = 4.4±0.1×10−9 M/s). The autoxidation rate determined by IC was highly correlated with the one measured using the oxygen uptake method (R2 = 0.99). The IC method accurately indicated the antioxidant capacity and rates of both inhibited and uninhibited periods, together with the oxidizability of mayonnaise samples. The mayonnaise made with extra virgin olive oil exhibited the lowest oxidizability, while sunflower oil showed maximum antioxidant efficiency. A significant advantage of the IC method was its ability to simultaneously measure up to 24 samples with minimal effort.

A comparative study on dynamic mechanical property and carbonation-hydration kinetics of CO2-cured high performance cementitious composites

High performance cementitious composites with limited carbon emission and enhanced dynamic mechanical property is prospective in developing eco-efficient concrete structures that can both sequestrate carbon and suffer impact loads especially for protection facilities. For the aim, static and dynamic mechanical properties of 2% steel fiber (wt.%), 15% silica fume (SF) and 20% fly ash microsphere (FAM) added cementitious composites with CO2 curing treatment were explored. Spilt Hopkinson Pressure Bar testing system (SHPB) coupled with high-speed camera were adopted, carbonation-hydration kinetics in the process of CO2 curing treatment was also focused using a modified isothermal calorimetry method. It was found that carbonated high performance cementitious composites of C-8 showed the highest 1-d and 56-d static compressive strengths, correspondingly with 63.4 MPa and 114.7 MPa, its dynamic compressive strength increased with strain rates, almost reached to 120 MPa at 111 s−1. Drastic carbonation heat flow with peak value of 0.044 W/g and a normally subsequent hydration process were innovatively revealed in the high performance cementitious composites.

Abstract 3844: A biophysical investigation into the binding interactions of novel anti-cancer inhibitors of atypical protein kinase C (aPKCs)

Abstract The aim of this study is to address the challenge of the expression of recombinant atypical protein kinase C (aPKCs) in a bacterial system and understand the binding interactions of novel anti-cancer inhibitors of aPKCs. The Protein kinase Cs (PKCs) expression at a high rate is a key indicator of cancer cell proliferation and survival. In particular, the over-expressions of aPKCs were found to be directly associated with various cancer cells in benign and malignant stages. Several cancer growth blockers (inhibitors) are available for targeted therapy. However, these inhibitors had to pass through rigorous in silico screening, in vitro, and in vivo assays before FDA approval. During the characterization studies of the protein, insights into binding interactions between aPKCs and drug molecules are crucial. For successive studies such as for biophysical characterization, the recombinant bioactive full-length PKC- ι (an aPKC) expression in the bacterial system is still a challenge. In addition, the binding interaction studies of aPKCs with inhibitors in physiological conditions providing structural details are limited to some X-ray crystallography structures and computational studies. Here we addressed these two challenges and report a protocol detailing the bioactive full-length and catalytic domain of PKC- ι expression and purification from the bacterial system. The further characterization of the recombinant protein by the determination of melting temperature, functional activity, and circular dichroism reported here provides important information on the characteristics of the protein in its native state. Moreover, we show the chemical interactions of five novel anti-cancer inhibitors ICA-1S (Nucleosidic homolog) 5-amino-1-((1R,2S,3S,4R)-2,3-dihydroxy-4-methylcyclopentyl)-1H-imidazole-4-carboxamide), ICA-1T (Phosphorylated nucleosidic homolog of ICA-1S, [4-(5-amino-4-carbamoylimidazol-1-yl)-2,3-dihydroxycyclopentyl] methyl dihydrogen phosphate), ACPD (2-acetyl-1,3-cyclopentanedione), DNDA (3,4-diaminonaphthalene-2,7-disulfonic acid) and ζ(ZETA)-Stat (8-hydroxy-1,3,6- naphthalenetrisulfonic acid) to locate their regions of binding on the catalytic domain of the aPKCs (PKC- ι and PKC- ζ). We have utilized the chemical shift changes obtained from various multi-dimensional Nuclear Magnetic Resonance (NMR) experiments. Moreover, we have applied the isothermal calorimetry method to understand the biophysical properties of the aPKCs in presence of these inhibitors. The observed biophysical properties of the protein and chemical shift perturbations in the amide backbone of the catalytic domain upon binding shed light on the molecular recognition process, binding characteristics, and atomic-level structural details of the aPKCs. Citation Format: Radwan Ebna Noor, Tracess B. Smalley, Mildred Acevedo-Duncan. A biophysical investigation into the binding interactions of novel anti-cancer inhibitors of atypical protein kinase C (aPKCs). [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3844.

Study of the cement systems reactivity modified with mineral additives

The influence of mineral fillers on the hydration of cement systems and the curing of concrete during their partial replacement of cement has been studied. A comprehensive approach based on a combination of isothermal calorimetry method and compressive strength tests was used in this work. The results obtained allowed to draw conclusions about the reactive pozzolanic activity of silica fume and metakaolin, the microreinforcing function of wollastonite, and the effect of the zeolite filler.

Advanced high-affinity glycoconjugate ligands of galectins

Galectins are proteins of the family of human lectins. By binding terminal galactose units of cell surface glycans, they moderate biological and pathological processes such as cell signaling, cell adhesion, apoptosis, fibrosis, carcinogenesis, and metabolic disorders. The binding of monovalent glycans to galectins is usually relatively weak. Therefore, the presentation of carbohydrate ligands on multivalent scaffolds can efficiently increase and/or discriminate the affinity of the glycoconjugate to different galectins. A library of glycoclusters and glycodendrimers with various structural presentations of the common functionalized N-acetyllactosamine ligand was prepared to evaluate how the mode of presentation affects the affinity and selectivity to the two most abundant galectins, galectin-1 (Gal-1) and galectin-3 (Gal-3). In addition, the effect of a one- to two-unit carbohydrate spacer on the affinity of the glycoconjugates was determined. A new design of the biolayer interferometry (BLI) method with specific AVI-tagged constructs was used to determine the affinity to galectins, and compared with the gold-standard method of isothermal titration calorimetry (ITC). This study reveals new routes to low nanomolar glycoconjugate inhibitors of galectins of interest for biomedical research.

Hydration and Mechanical Properties of Calcium Sulphoaluminate Cement Containing Calcium Carbonate and Gypsum under NaCl Solutions.

Hydration characteristics and mechanical properties of calcium sulphoaluminate (CSA) cement with different contents of CaCO3 and gypsum under NaCl solutions were studied, using the testing methods of isothermal calorimetry, X-ray diffraction (XRD), mercury intrusion porosimetry (MIP), linear shrinkage, and compressive strength. Results show that CaCO3 can promote hydration and reduce the hydration heat of CSA cement. The reaction between gypsum and C4A3 releases a large quantity of heat in the initial hydration period; however, over 3 days of accumulation, the level of hydration heat is reduced. Under NaCl solutions, the aluminate phase has difficulty reacting with CaCO3 to form carbonate phase but combines with chloride ions to form Friedel’s salt. On the contrary, gypsum reduces aluminate phase, and the content of Friedel’s salt is also reduced. Furthermore, CaCO3 and gypsum both increase the total porosity of the CSA cement paste under NaCl solutions during the early curing phase, and over the long-term, pore structure is also optimized. CaCO3 and gypsum reduce the linear shrinkage of CSA cement paste under NaCl solutions. Overall, the compressive strength of CSA cement is reduced with the addition of CaCO3, and the trend will be sharper with the increase in CaCO3. However, when it comes to gypsum, the compressive strength is almost the same during early curing, but in the long-term, compressive strength improves. Essentially, the compressive strength of CSA cement mortar with CaCO3 and gypsum will improve under NaCl solutions.

Estimation of maximum temperature attained during concrete cure for internal sulfate reaction prevention in structures

Nowadays, delayed ettringite formation, DEF, still constitutes one of the main causes of concrete degradation in massive concrete elements or structures in Portugal. The most effective way to prevent the deleterious development of DEF is to control the maximum temperature attained during concrete cure. The tools currently available to practitioners, for predicting the maximum temperature attained in a concrete element, require the previous knowledge of the heat of hydration of the cement to be used in the structure. Several methods can be used to determine it, although the most common has been the Lagavant method, i.e. by means of semi-adiabatic calorimetry, the isothermal conduction calorimetry method is now becoming a widely used method. Since the two test methods produce different values, it is important to establish a correlation between the results obtained with both and to determine their influence on the temperature estimate made with the currently available calculation tools. The laboratory and in-situ tests reported in this paper allowed to gather a relevant amount of data pertaining to the heat of hydration of cement types normally used on massive structures or structures with massive elements, with the two abovementioned standardized methods; to establish a correlation on the heat of hydration values obtained with the two methods; and to use those heat of hydration values to perform estimates of the maximum temperature attained during concrete cure of a particular concrete mixture, used in a real structural element, which were very close to those measured experimentally on an experimental concrete viaduct deck section.

Mechanical and radiation shielding properties of concrete containing commercial boron carbide powder

Boron-containing compounds have an excellent radiation shielding capability against slow neutrons. Moreover, sassolite in boron-containing compounds adversely affects cement hydration by retarding cement setting times. Accordingly, experimental and analytical investigations were carried out to examine the filler effect of commercial boron carbide (B4C) fine powder with a mean particle diameter of 2.64 μm on Portland cement hydration reaction, and concrete mechanical and radiation shielding properties. Isothermal calorimetry method was used to study the heat evolution and the cement degree of hydration of mixes containing 0, 25, 50 and 75% of B4C to cement by weight. Effects of adding B4C on concrete compressive strength were then investigated. Analytical investigations, specifically mass attenuation coefficient using WinXcom program and effective atomic number using Auto-Zeff, were carried out to evaluate the radiation shielding of corresponding concrete mixes for photon energies ranging from 10 keV to 10 MeV. Moreover, macroscopic effective removal cross-sections for fast neutrons and thermal neutron macroscopic absorption cross-sections were calculated using MRCsC program and JANIS-4 software, respectively. The results confirm that the presence of sassolite in the studied B4C powder retards the hydration reaction for the first 24 h and reveal significant improvements in concrete strength thereafter with the increase of boron carbide due to the filler effect. Furthermore, the addition of boron carbide yielded measurable improvement in neutron shielding capabilities of concrete mixes.

Measuring and modeling cement hydration kinetics at variable temperature conditions

The heat evolution during the hydration of a Class H oil well cement was examined by both the traditional isothermal calorimetry method and a new differential scanning calorimetry (DSC) method. Isothermal calorimetry tests were performed at four different temperatures: 15, 25, 40, and 60 °C. DSC tests were performed in two different modes: simple ramp mode in the temperature range from 24 to 100 °C, as well as “ramp and hold” mode, with final holding temperatures of 60, 80 and 260 °C, respectively. The ramp rate ranged from 0.3 to 4.8 °C/h. A scale factor model previous proposed to simulate cement hydration kinetics at isothermal conditions was further developed into a numerical format to simulate cement hydration at variable temperature conditions. Excellent agreements were observed between experimental and simulated results. The study not only provided a new method of measuring cement hydration kinetics but also further advanced our understanding of cement hydration mechanism.

Effects of Temperature on Lifespan of Drosophila melanogaster from Different Genetic Backgrounds: Links between Metabolic Rate and Longevity.

Despite many studies of the aging process, questions about key factors ensuring longevity have not yet found clear answers. Temperature seems to be one of the most important factors regulating lifespan. However, the genetic background may also play a key role in determining longevity. The aim of this study was to investigate the relationship between the temperature, genetic background (fruit fly origin), and metabolic rate on lifespan. Experiments were performed with the use of the wild type Drosophila melanogaster fruit flies originating from Australia, Canada, and Benin and the reference OregonR strain. The metabolic rate of D. melanogaster was measured at 20 °C, 25 °C, and 28 °C in an isothermal calorimeter. We found a strong negative relationship between the total heat flow and longevity. A high metabolic rate leads to increased aging in males and females in all strains. Furthermore, our results showed that temperature has a significant effect on fecundity and body weight. We also showed the usefulness of the isothermal calorimetry method to study the effect of environmental stress conditions on the metabolic activity of insects. This may be particularly important for the forecasting of impact of global warming on metabolic activity and lifespan of various insects.

Comparison of the Hydration Characteristics of UltraHighPerformance and Normal Cementitious Materials.

The hydration mechanism of ultra-high-performance cementitious materials (UHPC) departs considerably from that of normal cementitious materials (NC). In this study, the strength, isothermal calorimetry, chemical shrinkage, X-ray diffraction (XRD), and thermogravimetry (TG) methods are used to determine the hydration characteristics of UHPC and NC that contain silica fume (SF). A simple device was modified to test the chemical shrinkage for long-term growth, and the ultimate chemical shrinkage is obtained by semi-empirical formula fitting. It is found that the degree of hydration of UHPC is significantly lower than that of NC. The hydration kinetics analyzed using the Krstulovic-Dabic model shows that the hydration process of NC is type NG-I-D, which is characterized by gentle and prolonged hydration. However, the hydration of UHPC is type NG-D with the distinguishing features of early sufficiency and later stagnation. The growth of the strength, exothermic evolution, and phase development of UHPC is decelerated as the hydration process proceeds, which confirms the weak development tendency of hydration at the later stage. In addition, the effect of SF on the hydration of UHPC is minor, and the higher content of SF is beneficial to the hydration at the later stage.

Research on water transport behaviors and hydration characteristics of internal curing pavement concrete

This paper presents the influence of internal curing agent (super absorbent polymer, SAP) on the water transport behaviors and hydration characteristics of pavement concrete. The 1H nuclear magnetic resonance (NMR) test was performed to quantitatively analyze the transformation rule of different forms of water, and the variation rule of relative humidity in different vertical depths of concrete slab was also studied. Moreover, the isothermal calorimetry and thermogravimetry method were adopted to study the hydration process of internal curing pavement concrete. The flexural strength of specimens with SAPs were evaluated by the four-point bending method. Finally, the enhancement mechanism of SAP on the properties of pavement concrete was revealed through analyzing the water transport behaviors, hydration characteristics and microstructure characteristics. The results show that specimens with SAPs of smaller particle size could keep the humidity compensating and hydration enhancing process for a long time. The humidity gradient in the slab could be significantly reduced that might mitigate the humidity warping stress distributed in the slab. Although SAP delayed the hydration process of binding materials in the early age, it could greatly improve the hydration degree in the long term, which helps improving the crack resistance and the compactness of pavement concrete. The adhesion of aggregate-cement matrix interfacial transition zone (ITZ) and the compactness of microstructure was improved during the internal curing process.

Effective Absorption Capacity Examined by Isothermal Calorimetry: Effect of Pore Structure and Water‐to‐Cement Ratio

The accurate measurement of effective absorption capacity is crucial for highly absorptive materials when they are used within cement‐based materials. In this study, a method for examining effective absorption capacity using isothermal calorimetry is reviewed and investigated in detail to accommodate different circumstances. Specifically, the effect of different pore structures and water‐to‐cement ratios in determining effective absorption capacity is experimentally examined using activated carbon fibre and powdered activated carbon. The results suggest that the method may be suitable for porous materials with micropores but not suitable for those with mesopores. Also, the results indicate that the effective absorption capacity value can change with the water‐to‐cement ratio used. These findings can be used to find the effective absorption capacity of highly absorptive materials more accurately using the isothermal calorimetry method.

The influence of lithium carbonate on the heat release during the hydration of Portland cement at the temperature 40°C

This work represents the stage of the author's research aimed at identifying the solutions for increasing the energy efficiency of the production of precast concrete and reinforced concrete products and structures in plant conditions due to reducing the temperature of heat treatment, or due to the reduction of duration of this technological process. The work provides results of the research of the influence of the admixture of lithium carbonate (Li2CO3) on the dynamics of hydration process of the binding systems on a cement basis in the conditions of the increased temperature (40°C). The research was performed using the method of isothermal calorimetry on the two various samples of the cement binder, conducted in various countries. The Li2CO3 admixture is accepted in dosages from 0.5% to 2.5%. The graphical dependence of the heat flow of the exothermic reaction of hydration on the used lithium carbonate dosage in the first days of curing of the samples is established and presented.

Study of strength kinetics of sand concrete system of accelerated hardening

Methods of calorimetric analysis are used to study the dynamics of the hydration processes of concretes with different accelerator contents. The efficiency of the isothermal calorimetry method is shown for study of strength kinetics of concrete mixtures of accelerated hardening, promising for additive technologies in civil engineering.