Journal articles: 'Calorimetry testing'

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Reynard-Carette, C., G. Kohse, J. Brun, M. Carette, A. Volte, and A. Lyoussi. "Review of Nuclear Heating Measurement by Calorimetry in France and USA." EPJ Web of Conferences 170 (2018): 04019. http://dx.doi.org/10.1051/epjconf/201817004019.

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This paper gives a short review of sensors dedicated to measuring nuclear heating rate inside fission reactors in France and USA and especially inside Material Testing Reactors. These sensors correspond to heat flow calorimeters composed of a single calorimetric cell or of two calorimetric cells at least with a reference cell to obtain a differential calorimeter. The aim of this paper is to present the common running principle of these sensors and their own special characteristics through their design, calibration methods, and in-pile measurement techniques, and to describe multi-sensor probes including calorimeters.

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Moroń, Leszek, and Paweł Żyłka. "Simplified isoperibol calorimetry for thermal testing of dielectric and conducting materials." Archives of Electrical Engineering 60, no. 1 (March 1, 2011): 95–104. http://dx.doi.org/10.2478/v10171-011-0010-y.

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Simplified isoperibol calorimetry for thermal testing of dielectric and conducting materials A simplified isoperibol calorimetry method for measuring specific heat in solids is described. Taking advantage of the classical Nernst dependency the specific heat is calculated from time-domain temperature curves registered for a sample forced heating and natural cooling phase. In order to improve accuracy of the measurements a correction factor, taking into account the heat transferred to the surrounding, is introduced along with a procedure of statistical elimination of unavoidable measurement deviations. The method is implemented in a simple and straightforward measuring system involving no vacuum calorimeter. The method is applicable for quick and routine specific heat measurements performed on small solid dielectric or metallic specimens at near-room temperature. Test results of various materials used commonly in electrical engineering are demonstrated and discussed as well as comparison to drop calorimetry and differential scanning calorimetry reference measurements is included. The overall repeatability of the test method and the simplified apparatus is estimated as not worse than 2.6%.

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Kang, Sungwook, Minjae Kwon, Joung Yoon Choi, and Sengkwan Choi. "Thermal Boundaries in Cone Calorimetry Testing." Coatings 9, no. 10 (September 29, 2019): 629. http://dx.doi.org/10.3390/coatings9100629.

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Bench-scale cone calorimetry is often used to evaluate the fire performance of intumescent-type coatings. During the tests, the coating geometry inflates. These thick, block-shaped specimens expose their perimeter side surfaces to both the heat source and the surroundings, unlike the typical thin, plate-shaped samples used in flammability tests. We assessed the thermal boundaries of block-shaped specimens using plain steel solids with several thicknesses. The heat transmitted through the exposed boundaries in convection and radiation modes was determined by four sub-defining functions: non-linear irradiance, convective loss, and radiant absorption into and radiant emission from solids. The individual functions were methodically derived and integrated into numerical calculations. The predictions were verified by physical measurements of the metals under different heating conditions. The results demonstrate that (1) considering absorptivity, being differentiated from emissivity, led to accurate predictions of time-temperature relationships for all stages from transient, through steady, and to cooling states; (2) the determined values for the geometric view factor and the fluid dynamic coefficient of convection can be generalized for engineering applications; (3) the proposed process provides a practical solution for the determination of optical radiative properties (absorptivity and emissivity) for use in engineering; and (4) the heat transmitted through the side surfaces of block specimens should be included in energy balance, particularly in the quantification of a heat loss mechanism. This paper outlines a comprehensive heat transfer model for cone calorimetry testing, providing insights into the mechanism of complex heat transmission generated on the test samples and quantifying their individual contributions.

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Rattanachaiwong, Sornwichate, and Pierre Singer. "Indirect calorimetry as point of care testing." Clinical Nutrition 38, no. 6 (December 2019): 2531–44. http://dx.doi.org/10.1016/j.clnu.2018.12.035.

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Morgan, Alexander B., and Mary L. Galaska. "Flammability testing of wool/cellulosic and wool/synthetic fiber blends: Vertical flame spread and heat release results." Journal of Fire Sciences 38, no. 6 (November 2020): 522–51. http://dx.doi.org/10.1177/0734904120954013.

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Wool is a natural fiber with lower heat release/flammability than some synthetic fabrics, but it has not been well studied for its heat release when other fibers such as cotton, linen, and nylon are present in the woven fabric. In this article, the heat release and vertical flame spread of six commercially available natural color fabrics is reported. This includes 100% wool, 80% wool/20% nylon, 70% wool/30% linen, 45% wool/55% cotton, and 40% wool/38% cotton/12% nylon/10% metallic thread fabric. Heat release was measured through cone calorimetry (ASTM E1354) as a function of the sample mounting method, through microscale combustion calorimetry (ASTM D7309), and flame spread was measured by ASTM D6413. The type of insulated backing used greatly affected the cone calorimeter results, and fabric types did show some effects in vertical flame spread and microscale combustion calorimeter testing.

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Ahonen, Antti, Henry Weckman, and Martti Yli-Penttilä. "Application of oxygen-consumption calorimetry to non-combustibility testing." Fire and Materials 9, no. 3 (September 1985): 135–44. http://dx.doi.org/10.1002/fam.810090306.

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Toenjes, Anastasiya, Heike Sonnenberg, Christina Plump, Rolf Drechsler, and Axel von Hehl. "Measurement and Evaluation of Calorimetric Descriptors for the Suitability for Evolutionary High-Throughput Material Development." Metals 9, no. 2 (January 29, 2019): 149. http://dx.doi.org/10.3390/met9020149.

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A novel method for evolutionary material development by using high-throughput processing is established. For the purpose of this high-throughput approach, spherical micro samples are used, which have to be characterized, up-scaled to macro level and valued. For the evaluation of the microstructural state of the micro samples and the associated micro-properties, fast characterization methods based on physical testing methods such as calorimetry and universal microhardness measurements are developed. Those measurements result in so-called descriptors. The increase in throughput during calorimetric characterization using differential scanning calorimetry is achieved by accelerating the heating rate. Consequently, descriptors are basically measured in a non-equilibrium state. The maximum heating rate is limited by the possibility to infer the microstructural state from the calorimetric results. The substantial quality of the measured descriptors for micro samples has to be quantified and analyzed depending on the heating rate. In this work, the first results of the measurements of calorimetric descriptors with increased heating rates for 100Cr6 will be presented and discussed. The results of low and high heating rates will be compared and analyzed using additional microhardness measurements. Furthermore, the validation of the method regarding the suitability for the evolutionary material development includes up-scaling to macro level and therefore different sample masses will be investigated using micro and macro samples during calorimetry.

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Kang, Sungwook, Sengkwan Choi, and Joung Yoon Choi. "Coupled thermo-physical behaviour of an inorganic intumescent system in cone calorimeter testing." Journal of Fire Sciences 35, no. 3 (April 19, 2017): 207–34. http://dx.doi.org/10.1177/0734904117701765.

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This article examines the thermo-physical behaviour of an inorganic-based intumescent coating, tested with bench-scale cone calorimetry, in order to promote the understanding of its intumescence and to contribute to the optimisation of its thermal insulation performance. In the test, the specimen underwent the following phenomena simultaneously: (1) thermo-kinetic endothermic water vaporisation; (2) formation of micro-scale pores in its internal volume; (3) expansion of its volume; (4) variations in thermal boundaries. These simultaneous phenomena cause several changes in internal–external conditions given to the test sample: (1) loss of mass (water molecules); (2) reduction of effective thermal conductivity owing to its porous structure; (3) increase in length of the conductive heat transfer path across its expanding volume; (4) irradiance intensification and additional heat transfer generation on its moving boundaries, exposed to the heat source and surroundings. This interacting thermo-physical behaviour impedes the heat transfer to the underlying substrate. It is therefore comprehensively explained by finite element analysis, associated with the experimental data obtained from a thermogravimetric analyser, differential scanning calorimetry, electric furnace and cone calorimeter tests. The numerical predictions agreed with the physical measurements with consistent accuracy, in terms of both histories of substrate temperature and coating-thickness expansion. This combined numerical–experimental approach enables clear interpretation on the process of intumescence, the impediment mechanism of heat transfer and the critical factors of the material’s behaviour.

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Nocuń-Wczelik, Wiesława, Artur Łagosz, Bartosz Kowalski, and Marek Gawlicki. "Calorimetry in testing waste materials from the brown coal combustion." Journal of Thermal Analysis and Calorimetry 118, no. 1 (July 25, 2014): 123–31. http://dx.doi.org/10.1007/s10973-014-3963-4.

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Mura, P., G. P. Bettinetti, M. T. Faucci, A. Manderioli, and P. L. Parrini. "Differential scanning calorimetry in compatibility testing of picotamide with pharmaceutical excipients." Thermochimica Acta 321, no. 1-2 (November 1998): 59–65. http://dx.doi.org/10.1016/s0040-6031(98)00440-7.

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Bĕhálek, Luboš. "Differential Scanning Calorimetry as a Tool for Quality Testing of Plastics." Key Engineering Materials 669 (October 2015): 485–93. http://dx.doi.org/10.4028/www.scientific.net/kem.669.485.

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Differential scanning calorimetry (DSC) is the most frequently used method from thermal analysis to characterize plastics and which can be applied not only in the R&D but also in the industrial praxis as input and output control. This paper deals with the most important DSC application which arises from results of applied and contractual research at Technical university of Liberec. In the paper are introduced examples of its utilization for plastics identification and characterization, for analysis influence of plastics processing process parameters on their quality, to describe crystallization kinetics and so on.

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Kayaert, P., B. Li, I. Jimidar, P. Rombaut, F. Ahssini, and G. Van den Mooter. "Solution calorimetry as an alternative approach for dissolution testing of nanosuspensions." European Journal of Pharmaceutics and Biopharmaceutics 76, no. 3 (November 2010): 507–13. http://dx.doi.org/10.1016/j.ejpb.2010.09.009.

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Angiuli, M., C. Ferrari, L. Lepori, E. Matteoli, G. Salvetti, E. Tombari, A. Banti, and N. Minnaja. "On testing quality and traceability of virgin olive oil by calorimetry." Journal of Thermal Analysis and Calorimetry 84, no. 1 (April 2006): 105–12. http://dx.doi.org/10.1007/s10973-005-7184-8.

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Volte, A., C. Reynard-Carette, J. Brun, C. De Vita, M. Carette, T. Fiorido, A. Lyoussi, D. Fourmentel, J.-F. Villard, and P. Guimbal. "Study of the Flow Temperature and Ring Design Influence on the Response of a New Reduced-Size Calorimetric Cell for Nuclear Heating Quantification." EPJ Web of Conferences 170 (2018): 04026. http://dx.doi.org/10.1051/epjconf/201817004026.

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This paper concerns experimental studies of different designs of a new compact calorimetric cell under laboratory conditions. This kind of cell is used for the measurement of the nuclear heating rate inside Material Testing Reactors thanks to differential calorimetry. The results, obtained by applying an operating protocol corresponding to a preliminary out-of-pile calibration step, are presented for three designs. The influence of the horizontal-fin design is shown on the calibration curve and the sensor sensitivity. The influence of the external fluid flow temperature is given for the quarter design. The different responses of the calorimetric cell are explained by taken into account a 1D analytical thermal model coupling thermal conductive and radiative transfers.

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Rogers, Richard L. "The advantages and limitations of adiabatic Dewar calorimetry in chemical hazard testing." Plant/Operations Progress 8, no. 2 (April 1989): 109–12. http://dx.doi.org/10.1002/prsb.720080217.

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Kino, M., N. Kawakatu, and F. Takahara. "CALORIMETRY OF ACTIVE GALACTIC NUCLEUS JETS: TESTING PLASMA COMPOSITION IN CYGNUS A." Astrophysical Journal 751, no. 2 (May 10, 2012): 101. http://dx.doi.org/10.1088/0004-637x/751/2/101.

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Eaton-Evans, J., J. M. Dulieu-Barton, E. G. Little, and I. A. Brown. "Observations during mechanical testing of Nitinol." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 222, no. 2 (February 1, 2008): 97–105. http://dx.doi.org/10.1243/09544062jmes797.

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Superelastic and shape memory capabilities of Nitinol are strongly dependent on the alloy composition, its heat treatment, and mechanical deformation history. The current article presents a review of the behaviour of Nitinol and describes a characterization study conducted to determine the mechanical properties of the material, both by means of differential scanning calorimetry (DSC) and by mechanical testing at a range of temperatures. Values for key transformation temperatures are found using both techniques. It is concluded that mechanical deformation during sample preparation for DSC measurements may have led to material property modifications and hence erroneous phase transformation temperature values. It is shown that mechanical testing can provide a means of benchmarking DSC data.

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Easson, Michael W., Jacobs Harris Jordan, SeChin Chang, John M. Bland, and Brian Douglas Condon. "Investigation of bisphenol-substituted spirocyclic phosphazenes as cotton textile–based flame retardants." Journal of Engineered Fibers and Fabrics 15 (January 2020): 155892502092088. http://dx.doi.org/10.1177/1558925020920887.

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Bisphenol-substituted spirocyclic phosphazene derivatives were synthesized in 85%–94% yields and analyzed for flame retardant application to cotton fabric using Limiting Oxygen Index, Fourier transform infrared thermogravimetric analysis, differential scanning calorimetry, microscale combustion calorimetry, thermogravimetric analysis, and scanning electron microscopy. The thermogravimetric analysis methods indicate a decomposition pathway consistent for phosphorus-nitrogen-containing compounds. Levoglucosan phosphorylation and carbonaceous char formation were observed. Limiting Oxygen Index testing of these compounds on cotton-based fabrics showed improved flame resistance compared to untreated fabrics.

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Jiang, Lin, Filippo Berto, and Dan Zhang. "Pyrolysis Kinetics and Flammability Evaluation of Rigid Polyurethane with Different Isocyanate Content." Molecules 26, no. 8 (April 20, 2021): 2386. http://dx.doi.org/10.3390/molecules26082386.

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Polyurethane (PU) is a typical product of the reaction between isocyanate and polyol, whose ratio would greatly influence material properties. In this paper, to investigate the influence of isocyanate on PU thermal stability and flammability, three kinds of rigid polyurethanes (RPUs) with different isocyanate ratio (1.05, 1.1, and 2.0) were manufactured in a laboratory and employed to have a series of TG (thermogravimetry), DSC (differential scanning calorimetry), and cone calorimetry tests. Kissinger’s method was used to calculate the activation energy and judge their stabilities. However, for such a complex degradation which consists of five reactions, it does not make sense by Kissinger method to obtain only two peak active energies. Considering complexity of PU degradation in air, genetic algorithm (GA) was employed to calculate kinetic triplets of five sub-reactions. The effects of isocyanate contents on each sub-reaction stability were obtained and then analyzed. By cone calorimeter testing, we found that great differences in heat release rate data. However, DSC analysis showed a complete opposite changed trend. Such difference is caused by DSC and calorimeter’s sample morphology, the former using grinded polyurethane powders but the latter polyurethane foam block.

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Van Oosten, Brad, Drew Marquardt, and Thad A. Harroun. "Testing High Concentrations of Membrane Active Antibiotic Chlorhexidine Via Computational Titration and Calorimetry." Journal of Physical Chemistry B 121, no. 18 (May 2, 2017): 4657–68. http://dx.doi.org/10.1021/acs.jpcb.6b12510.

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Oliyai, Reza, and Siegfried Lindenbaum. "Stability testing of pharmaceuticals by isothermal heat conduction calorimetry: Ampicillin in aqueous solution." International Journal of Pharmaceutics 73, no. 1 (June 1991): 33–36. http://dx.doi.org/10.1016/0378-5173(91)90097-8.

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Kang, Sungwook, J. Choi, and Sengkwan Choi. "Mechanism of Heat Transfer through Porous Media of Inorganic Intumescent Coating in Cone Calorimeter Testing." Polymers 11, no. 2 (January 29, 2019): 221. http://dx.doi.org/10.3390/polym11020221.

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This work discusses the heat transfer process through a particular form of porous media: an inorganic-based intumescent coating in full-expansion state. Although the thermal mechanism in porous media has been vigorously studied for polymeric/ceramic/metallic foams, less information is available on its application with intumescent-type polymers. This examination demonstrates the procedure of (1) the optimisation of the coating’s internal multicellular structure for numerical modelling, based on topological analyses; (2) the finite element simulation for the coating-sample tested with cone calorimetry; and (3) the quantitative evaluation of the thermal insulation performance of its porous structure by adopting effective thermal conductivity. The modelling technique was verified using measurable data from the cone calorimeter tests. Consistent agreement between the numerical predictions and experimental measurements was achieved over the whole steel-substrate temperature history, based on the clarified thermal boundaries of the specimen and modelling of the combined conduction-radiation transfer. This numerical approach exhibits the impacts of porosity, pore-size, and external thermal load on the medium’s performance, as well as the individual contributions of the component heat transfer modes to the overall process. The full understanding of this thermal mechanism can contribute to the enhancement and optimisation of the thermal insulation performance of a porous-type refractory polymer.

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Kim, Do-yeon, and Robert Andrew Robergs. "Validation of a new mixing chamber system for breath-by-breath indirect calorimetry." Applied Physiology, Nutrition, and Metabolism 37, no. 1 (February 2012): 157–66. http://dx.doi.org/10.1139/h11-147.

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Limited validation research exists for applications of breath-by-breath systems of expired gas analysis indirect calorimetry (EGAIC) during exercise. We developed improved hardware and software for breath-by-breath indirect calorimetry (NEW) and validated this system as well as a commercial system (COM) against 2 methods: (i) mechanical ventilation with known calibration gas, and (ii) human subjects testing for 5 min each at rest and cycle ergometer exercise at 100 and 175 W. Mechanical calibration consisted of medical grade and certified calibration gas ((4.95% CO2, 12.01% O2, balance N2), room air (20.95% O2, 0.03% CO2, balance N2), and 100% nitrogen), and an air flow turbine calibrated with a 3-L calibration syringe. Ventilation was mimicked manually using complete 3-L calibration syringe manouvres at a rate of 10·min–1 from a Douglas bag reservoir of calibration gas. The testing of human subjects was completed in a counterbalanced sequence based on 5 repeated tests of all conditions for a single subject. Rest periods of 5 and 10 min followed the 100 and 175 W conditions, respectively. COM and NEW had similar accuracy when tested with known ventilation and gas fractions. However, during human subjects testing COM significantly under-measured carbon dioxide gas fractions, over-measured oxygen gas fractions and minute ventilation, and resulted in errors to each of oxygen uptake, carbon dioxide output, and respiratory exchange ratio. These discrepant findings reveal that controlled ventilation and gas fractions are insufficient to validate breath-by-breath, and perhaps even time-averaged, systems of EGAIC. The errors of the COM system reveal the need for concern over the validity of commercial systems of EGAIC.

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Kuriyama, Nobuhiro, and Minoru Sakiyama. "Construction and testing of a gas-solid reaction calorimetry system using a Tian-Calvet microcalorimeter." Thermochimica Acta 132 (September 1988): 75–87. http://dx.doi.org/10.1016/0040-6031(88)87097-7.

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Montanari, Luca, Jussara Tanesi, Haejin Kim, and Ahmad Ardani. "Quantification of Calcium Oxychloride by Differential Scanning Calorimetry: Validation and Optimization of the Testing Procedure." Advances in Civil Engineering Materials 10, no. 1 (June 9, 2021): 20200122. http://dx.doi.org/10.1520/acem20200122.

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Niu, Mingjun, Zhongzhou Zhang, Zizhen Wei, and Wanjie Wang. "Effect of a Novel Flame Retardant on the Mechanical, Thermal and Combustion Properties of Poly(Lactic Acid)." Polymers 12, no. 10 (October 19, 2020): 2407. http://dx.doi.org/10.3390/polym12102407.

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Poly(lactic) acid (PLA) is one of the most promising biobased materials, but its inherent flammability limits its applications. A novel flame retardant hexa-(DOPO-hydroxymethylphenoxy-dihydroxybiphenyl)-cyclotriphosphazene (HABP-DOPO) for PLA was prepared by bonding 9,10-dihydro-9-oxy-10-phosphaphenanthrene-10-oxide (DOPO) to cyclotriphosphazene. The morphologies, mechanical properties, thermal stability and burning behaviors of PLA/HABP-DOPO blends were investigated using a scanning electron microscope (SEM), a universal mechanical testing machine, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), limiting oxygen index (LOI), vertical burning (UL-94) and a cone calorimeter test (CCT). The LOI value reached 28.5% and UL-94 could pass V-0 for the PLA blend containing 25 wt% HABP-DOPO. A significant improvement in fire retardant performance was observed for PLA/HABP-DOPO blends. PLA/HABP-DOPO blends exhibited balanced mechanical properties. The flame retardant mechanism of PLA/HABP-DOPO blends was evaluated.

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Jiang, Li Zhong, Feng Dan Jiang, Jun Zhong Yang, Rui Kang Li, and Yan Ping Hu. "Influence of Novel Nucleating Agent on the Mechanical Properties and Crystallinity of Polyoxymethylene." Advanced Materials Research 466-467 (February 2012): 31–35. http://dx.doi.org/10.4028/www.scientific.net/amr.466-467.31.

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A novel nucleating agent for polyoxymethylene (POM) was successfully prepared. The effect of nucleating agent on POM was characterized by using mechanical properties testing machine and differential scanning calorimetry (DSC). The results demonstrate that the addition of nucleating agent can improve the crystallization growth rate and mechanical properties of POM, and the nucleating agent maybe have potential application in POM field.

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Kang, Kyeung Ho, Mingu Kang, Siho Shin, Jaehyo Jung, and Meina Li. "Estimating Physical Activity Energy Expenditure Using an Ensemble Model-Based Patch-Type Sensor Module." Electronics 10, no. 7 (April 5, 2021): 861. http://dx.doi.org/10.3390/electronics10070861.

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Chronic diseases, such as coronary artery disease and diabetes, are caused by inadequate physical activity and are the leading cause of increasing mortality and morbidity rates. Direct calorimetry by calorie production and indirect calorimetry by energy expenditure (EE) has been regarded as the best method for estimating the physical activity and EE. However, this method is inconvenient, owing to the use of an oxygen respiration measurement mask. In this study, we propose a model that estimates physical activity EE using an ensemble model that combines artificial neural networks and genetic algorithms using the data acquired from patch-type sensors. The proposed ensemble model achieved an accuracy of more than 92% (Root Mean Squared Error (RMSE) = 0.1893, R2 = 0.91, Mean Squared Error (MSE) = 0.014213, Mean Absolute Error (MAE) = 0.14020) by testing various structures through repeated experiments.

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Moon, Hoon, Sivakumar Ramanathan, Prannoy Suraneni, Chang-Seon Shon, Chang-Joon Lee, and Chul-Woo Chung. "Revisiting the Effect of Slag in Reducing Heat of Hydration in Concrete in Comparison to Other Supplementary Cementitious Materials." Materials 11, no. 10 (September 27, 2018): 1847. http://dx.doi.org/10.3390/ma11101847.

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Blast furnace slag (SL) is an amorphous calcium aluminosilicate material that exhibits both pozzolanic and latent hydraulic activities. It has been successfully used to reduce the heat of hydration in mass concrete. However, SL currently available in the market generally experiences pre-treatment to increase its reactivity to be closer to that of portland cement. Therefore, using such pre-treated SL may not be applicable for reducing the heat of hydration in mass concrete. In this work, the adiabatic and semi-adiabatic temperature rise of concretes with 20% and 40% SL (mass replacement of cement) containing calcium sulfate were investigated. Isothermal calorimetry and thermal analysis (TGA) were used to study the hydration kinetics of cement paste at 23 and 50 °C. Results were compared with those with control cement and 20% replacements of silica fume, fly ash, and metakaolin. Results obtained from adiabatic calorimetry and isothermal calorimetry testing showed that the concrete with SL had somewhat higher maximum temperature rise and heat release compared to other materials, regardless of SL replacement levels. However, there was a delay in time to reach maximum temperature with increasing SL replacement level. At 50 °C, a significant acceleration was observed for SL, which is more likely related to the pozzolanic reaction than the hydraulic reaction. Semi-adiabatic calorimetry did not show a greater temperature rise for the SL compared to other materials; the differences in results between semi-adiabatic and adiabatic calorimetry are important and should be noted. Based on these results, it is concluded that the use of blast furnace slag should be carefully considered if used for mass concrete applications.

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Brage, Søren, Ulf Ekelund, Niels Brage, Mark A. Hennings, Karsten Froberg, Paul W. Franks, and Nicholas J. Wareham. "Hierarchy of individual calibration levels for heart rate and accelerometry to measure physical activity." Journal of Applied Physiology 103, no. 2 (August 2007): 682–92. http://dx.doi.org/10.1152/japplphysiol.00092.2006.

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Combining accelerometry with heart rate (HR) monitoring may improve precision of physical activity measurement. Considerable variation exists in the relationships between physical activity intensity (PAI) and HR and accelerometry, which may be reduced by individual calibration. However, individual calibration limits feasibility of these techniques in population studies, and less burdensome, yet valid, methods of calibration are required. We aimed to evaluate the precision of different individual calibration procedures against a reference calibration procedure: a ramped treadmill walking-running test with continuous measurement of PAI by indirect calorimetry in 26 women and 25 men [mean (SD): 35 ( 9 ) yr, 1.69 (0.10) m, 70 ( 14 ) kg]. Acceleration (along the longitudinal axis of the trunk) and HR were measured simultaneously. Alternative calibration procedures included treadmill testing without calorimetry, submaximal step and walk tests with and without calorimetry, and nonexercise calibration using sleeping HR and gender. Reference accelerometry and HR models explained >95% of the between-individual variance in PAI ( P < 0.001). This fraction dropped to 73 and 81%, respectively, for accelerometry and HR models calibrated with treadmill tests without calorimetry. Step-test calibration captured 62–64% (accelerometry) and 68% (HR) of the variance between individuals. Corresponding values were 63–76% and 59–61% for walk-test calibration. There was only little benefit of including calorimetry during step and walk calibration for HR models. Nonexercise calibration procedures explained 54% (accelerometry) and 30% (HR) of the between-individual variance. In conclusion, a substantial proportion of the between-individual variance in relationships between PAI, accelerometry, and HR is captured with simple calibration procedures, feasible for use in epidemiological studies.

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Bader, Alexander, Anastasiya Toenjes, Nicole Wielki, Andreas Mändle, Ann-Kathrin Onken, Axel von Hehl, Daniel Meyer, Werner Brannath, and Kirsten Tracht. "Parameter Optimization in High-Throughput Testing for Structural Materials." Materials 12, no. 20 (October 21, 2019): 3439. http://dx.doi.org/10.3390/ma12203439.

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High-throughput screenings are established evaluation methods in the development of functional materials and pharmaceutical active ingredients. The transfer of this approach to the development of structural materials requires extensive adaptations. In addition to the investigation of new test procedures for the determination of material properties and the treatment of metallic materials, the design of experiments is a research focus. Based on given descriptor target values, the statistical design of experiments determines investigations and treatments for the investigation of these materials. In this context, process parameters also have to be determined, as these have a major influence on the later material properties, especially during the treatment of samples. In this article, a method is presented which determines the process parameters iteratively. The validation of the calculated process parameters takes place based on differential scanning calorimetry used as the furnace for the heat treatment of small batches and particle-oriented peening as the characterization method.

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Udomkitpanya, Thamolwan, and Kawee Srikulkit. "Properties of Poly(Lactic Acid) Blended with Natural Rubber-Graft- Poly(Acrylic Acid)." Key Engineering Materials 845 (May 2020): 45–50. http://dx.doi.org/10.4028/www.scientific.net/kem.845.45.

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Poly(acrylic acid) (PAA) was grafted onto natural rubber (NR) to improve the compatibility of NR and poly(lactic acid) (PLA). Polymer blend between PLA and NR-g-PAA was prepared by an internal mixer. Fourier-transform infrared spectroscopy (FT-IR), tensile testing, impact testing, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were employed to determine the functional group, mechanical properties and thermal properties of blends, respectively. Results showed that the addition of NR-g-PAA significantly improved the elongation, impact strength and thermal stability of blends. The P70N30 was the optimum composition to obtain improved mechanical properties of PLA.

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Weise, David R., Robert H. White, Frank C. Beall, and Matt Etlinger. "Use of the cone calorimeter to detect seasonal differences in selected combustion characteristics of ornamental vegetation." International Journal of Wildland Fire 14, no. 3 (2005): 321. http://dx.doi.org/10.1071/wf04035.

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The flammability of living vegetation is influenced by a variety of factors, including moisture content, physical structure and chemical composition. The relative flammability of ornamental vegetation is of interest to homeowners seeking to make their homes ‘fire safe’. The relative importance of the factors influencing fire behaviour characteristics, such as flammability, is unknown. In the present study, oxygen consumption calorimetry was used to obtain selected combustion characteristics of ornamental vegetation. Peak heat release rate, mass loss rate, time to ignition and effective heat of combustion of 100 × 100-mm samples of foliage and small branches were measured using a bench-scale cone calorimeter. Green and oven-dry samples of 10 species were collected and tested seasonally for a period of 1 year. Similar measurements were made on whole shrubs in an intermediate-scale calorimeter. The range of cone calorimeter peak heat release rates for green and oven-dry samples was 1–176 and 49–331 kW m−2, respectively. Moisture content significantly reduced heat release rates and increased time to ignition. Peak heat release rates for Olea europea and Adenostoma fasciculatum were consistently highest over the year of testing; Aloe sp. consistently had the lowest heat release rate. The correlation of peak heat release rates measured by the cone calorimeter and an intermediate-scale calorimeter was statistically significant yet low (0.51). The use of the cone calorimeter as a tool to establish the relative flammability rating for landscape vegetation requires additional investigation.

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Zhu, Kai, Yunhe Wang, Daquan Tang, Qiang Wang, Haihang Li, Yadong Huang, Zhiyi Huang, and Ke Wu. "Flame-Retardant Mechanism of Layered Double Hydroxides in Asphalt Binder." Materials 12, no. 5 (March 8, 2019): 801. http://dx.doi.org/10.3390/ma12050801.

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The flame retardancy of asphalt binders with layered double hydroxides (LDHs) was investigated using limiting oxygen index (LOI) and cone calorimeter tests. The flame-retardant mechanism of the LDHs was also studied with thermogravimetry and differential scanning calorimetry (TG–DSC), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The cone calorimeter testing results indicated that 2 wt.% of the LDHs can decease the peak heat and smoke release rate of asphalt binders. Because a low dose of LDHs can be well dispersed in asphalt binder and favor the formation of polyaromatic structures during combustion, the thermal oxidation resistance and compactness of the char layer can be improved. The LOI of asphalt binder can be increased and the heat and smoke release during combustion can be decreased with 25 wt.% LDHs. The decomposition of LDHs can absorb the heat release of the initial two stages of asphalt combustion and reduce the burning rate of asphalt. Due to the loss of loosely bound water in the LDHs during the blending process and the decrease of dispersibility at a high LDH dose, the improvement of thermal stability is limited.

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Tuissi, Ausonio, Mauro Coduri, and Carlo Alberto Biffi. "Laser shape setting of superelastic nitinol wires: Functional properties and microstructure." Functional Materials Letters 10, no. 01 (February 2017): 1740008. http://dx.doi.org/10.1142/s1793604717400082.

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Shape setting is one of the most important steps in the production route of Nitinol Shape Memory Alloys (SMAs), as it can fix the functional properties, such as the shape memory effect and the superelasticity (SE). The conventional method for making the shape setting is performed at 400–500[Formula: see text]C in furnaces. In this work, a laser beam was adopted for performing straight shape setting on commercially available austenitic Nitinol thin wires. The laser beam, at different power levels, was moved along the wire length for inducing the functional performances. Calorimetric, pseudo-elastic and microstructural features of the laser annealed wires were studied through differential scanning calorimetry, tensile testing and high energy X-ray diffraction, respectively. It can be stated that the laser technology can induce SE in thin Nitinol wires: the wire performances can be modulated in function of the laser power and improved functional properties can be obtained.

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Zhang, Duo You, Peng Liu, Chun Fa Ouyoung, Qun Gao, Kang Sheng Zheng, He Feng Hu, and Zhi Jie Li. "Influence of PNA012 on Crystallization and Mechanical Properties of Polybutylene Terephthalate." Advanced Materials Research 624 (December 2012): 264–68. http://dx.doi.org/10.4028/www.scientific.net/amr.624.264.

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PNA012 is a new nucleating agent on polybutylene terephthalate. The effect of different dosage of PNA012 on crystallization and mechanical properties were investigated by means of differential scanning calorimetry, universal testing machine, melt flow indexer and vicat softening testing machine. It was revealed that the PNA012 could substantially accelerate the crystallization of PBT. Compared with the pure PBT,the crystallization temperature of PBT/PNA012 rises from 196.3 °C to 199.7 °C and crystallization degree from 34.2% to 39.9%. The tensile Strength of PBT/PNA012 is increased 9.7%. The Bending Strength has a rise of 9.3% and the heat distortion temperatures of PBT/PNA012 is increased from 115.07°C to 125.94°C.

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Gu, Xiao Hua, Bao Yun Xu, Peng Zeng, Xi Wei Zhang, and Xi Jun Liu. "Preparation and Performance Research of the PBC / PLA Biodegradable Film." Applied Mechanics and Materials 470 (December 2013): 62–65. http://dx.doi.org/10.4028/www.scientific.net/amm.470.62.

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This paper mainly describes a novel biodegradable material poly (butylene carbonate) (PBC) to blending toughing modification for polylactic acid (PLA), and prepared the PBC/PLA biodegradable film) of improved toughness. To research the effect of thermol performance and mechanical properties (tensile strength and breaking elongation rate) through Fourier transform infrared spectroscopy (FTIR), differential thermal scanning calorimetry analysis (DSC) and tensile testing to expound different ratio of PBC and additive plasticizer, (lubricant and chain extender) .

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Zubielewicz, Małgorzata, and Agnieszka Królikowska. "Application of Research Methods in Expert Opinions." Solid State Phenomena 227 (January 2015): 541–44. http://dx.doi.org/10.4028/www.scientific.net/ssp.227.541.

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Most of the modern instrumental methods are mainly applicable only in R&D work. It is shown that some of them could be also used in the field, proving very useful in solving practical corrosion problems. The use of the following methods for testing coatings and substrates are discussed: scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), optical microscopy, Fourier transformation infrared analysis (FTIR), electrochemical impedance spectroscopy (EIS) and differential scanning calorimetry (DSC).

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Tang, Jie, Dan Chen, Gen Zhang, Hongwei Yang, and Guangbin Cheng. "A “Green” Primary Explosive: Design, Synthesis, and Testing." Synlett 30, no. 08 (February 5, 2019): 885–92. http://dx.doi.org/10.1055/s-0037-1611696.

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This account presents the synthesis and the characterization of triazine-tetrazine nitrogen heterocyclic compounds. Some compounds were characterized by NMR and IR spectroscopy, mass spectrometry, differential scanning calorimetry (DSC), and single-crystal X-ray diffraction. The physical and chemical properties were obtained by EXPLO5 v6.01, gas pycnometer, BAM Fallhammer, BAM Friction tester, and several detonation tests. The results show that the new metal-free polyazido compound 3,6-bis-[2-(4,6-diazido-1,3,5-triazin-2-yl)-diazenyl]-1,2,4,5-tetrazine (4) with high heat of formation (2820 kJ mol–1/6130.2 kJ kg–1) and excellent detonation velocity and pressure (D = 8602 m s–1, P = 29.4 GPa) could be used as ingredient in secondary explosives. 3,6-Bis-[2-(4,6-diazido-1,3,5-triazin-2-yl)-hydrazinyl]-1,2,4,5-tetrazine (3) can detonate research department explosive (RDX, cyclonite) as a primer (Δf H m = 2114 kJ mol–1/4555.2 kJ kg–1, D = 8365 m s–1, P = 26.8 GPa), whose initiation capacity is comparable to that of the traditional primary explosive Pb(N3)2. Therefore, the metal-free compound 3 can potentially replace lead-based-primary explosives, which would be advantageous for the environment.1 Introduction2 Strategies to Form High-Nitrogen Compounds with High Heat of Formation3 Metal-Free Strategies to Prepare Primary Explosives4 Concluding Remarks

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Balasubramanian, K. R., S. P. Sivapirakasham, and Jiss Mathew. "Analysis of Chemical Degradative Effects on Low Voltage PVC Insulation Using DSC." Applied Mechanics and Materials 592-594 (July 2014): 2475–80. http://dx.doi.org/10.4028/www.scientific.net/amm.592-594.2475.

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PVC insulation has extensively been used for insulating low voltage electrical cables. They offer superior insulating properties but how ageing and exposure could affect their insulation properties is a matter of concern. Chemical exposure related failure modes are known but have received only limited study. The traditional testing methods like insulation testing could only test whether the present properties are satisfactory. The application of thermal analysis methods like differential scanning calorimetry could identify the variation in thermal characteristics with respect to ageing and chemical exposure. Polluted environments may cause a direct attack upon a polymer. It has been concluded that significant changes in the behavior of insulation occurs in acidic environment that may lead to insulation failures.

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Lee, Sang Yong, Han Shin Choi, Chang Hee Lee, and Yong Jin Kim. "Characteristics of Ni-Ti-Zr-Si-Sn Bulk Amorphous HVOF Coating." Materials Science Forum 449-452 (March 2004): 929–32. http://dx.doi.org/10.4028/www.scientific.net/msf.449-452.929.

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This study was conducted to observe the influence of oxygen to fuel ratio[O2/H2ratio] of HVOF(High Velocity Oxygen Fuel) process on the amorphous formation and coating properties of NiTiZrSiSn bulk amorphous alloy. The bulk amorphous feedstock was prepared by inert gas atomization. Amorphous contents were followed by differential scanning calorimetry(DSC). Microstructural characterization was done by scanning electron microscope(SEM) and x-ray diffraction(XRD). Mechanical properties were obtained by Vickers microhardness testing and pin on disk wear testing. A maximum 72% amorphous phase could be obtained with an optimum O2/H2ratio. High amorphous content resulted in a low friction coefficient and weight loss than high oxide content coating and fully crystallized coating.

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Solokhina, Anna, Gernot Bonkat, Ekatherina Kulchavenya, and Olivier Braissant. "Drug susceptibility testing of mature Mycobacterium tuberculosis H37Ra and Mycobacterium smegmatis biofilms with calorimetry and laser spectroscopy." Tuberculosis 113 (December 2018): 91–98. http://dx.doi.org/10.1016/j.tube.2018.09.010.

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Laksono, Andromeda Dwi, and Diah Tri Agustiningtyas. "Pengaruh Faktor Geografi Terhadap Karakteristik Bambu Petung." SPECTA Journal of Technology 3, no. 1 (December 5, 2019): 25–32. http://dx.doi.org/10.35718/specta.v3i1.115.

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In this study was about a comparison of geographic factors towards the characterization of petung bamboo in Indonesia and the Philippines. Bamboo is one of the plants that has advantages in the field of technical materials based on developments in composite materials and is found in various regions. In general, bamboo has lignin and cellulose, where the morphology and nature of both bamboos are not the same from different countries. Therefore,material testing was carried out on each Indonesian and Filipino petung bamboo using material characterization testing methods. The process of Differential Scanning Calorimetry (DSC) was carried out to measure calorimetry with the yield of melting point in Philippine petung bamboo at 341ºC which is lower than the melting point in Indonesian petung bamboo which is 354.34ºC. In this DSC test, quantitative and qualitative results were obtainedin the form of phase changes, melting, and transition temperatures that occurred. Then an Energy Dispersive Spectrometer (EDS) was analyzed and the carbon content of cellulose and lignin was higher in Indonesian petung bamboo, respectively 65.29 wt.% And 66.05 wt.%. The morphology of bamboo shows that the fibers and matrices present in Philippine petung bamboo are denser than those of Indonesian petung bamboo. The highest peak value based on X-Ray Diffraction (XRD) is found in Philippine petung bamboo at 2ș of 34.49 and cubic phase.

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Šiler, Pavel, Ondřej Bezděk, Iva Kolářová, Eva Bartoníčková, Tomáš Opravil, and František Šoukal. "The Influence of Aggregates on the Properties of Concrete." Advanced Materials Research 1000 (August 2014): 277–80. http://dx.doi.org/10.4028/www.scientific.net/amr.1000.277.

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This work is focused on the influence of aggregates on the mechanical properties of concrete and hydration process. The flexural strength and compressive strength were observed after 1, 7 and 28 days of curing. The process of hydration was monitored using isoperibolic calorimetry. Laser particle size analysis of aggregates was also performed. The following materials were used: Portland cement CEM I 42,5 R-Sc, finely ground silica sand, calcinated bauxite, fine, medium and rough testing sand (defined in ČSN EN 196-1).

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Ponkratov, Yu V., V. S. Bochkov, K. K. Samarkhanov, I. S. Karambayeva, and S. K. Askerbekov. "Methodology of Corrosion Testing of Nuclear and Fusion Reactors Materials Using TGA/DSC and MS Complex Techniques." Eurasian Chemico-Technological Journal, no. 1 (February 20, 2019): 35. http://dx.doi.org/10.18321/ectj787.

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The behavior of structural materials of nuclear and fusion reactors during operation largely determines their safe and economical work. Structural materials of nuclear and fusion reactors are operating under conditions of interaction with various chemical active elements (gases, vapor-gas mixtures, fission products, etc.) in a wide temperature range; they are subject to high requirements in terms of their thermal and corrosion resistance. This paper presents the new methodology of complex studies on structural materials corrosion resistance of nuclear and fusion reactors with different gases and vapor-gas mixtures by thermal-gravimetric analysis (TGA), differential-scanning calorimetry (DSC) and mass spectrometry (MS) methods simultaneously.

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Xu, Qijie, Xiantao Feng, Junhe Liu, and Peijun Gong. "Preparation of Ag nanoparticles-reinforced polyamide 6 nanocomposites by in situ polymerization and investigation of its properties." Polish Journal of Chemical Technology 19, no. 4 (December 1, 2017): 36–40. http://dx.doi.org/10.1515/pjct-2017-0065.

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Abstract Polyamide 6 (noted as PA6)/Ag nanocomposites were prepared by an in situ solution polymerization method. AgNO3 was used as filler and was directly reduced to silver nanoparticles resulting in uniformly dispersed nanoparticles in the PA6 matrix. The thermal stability, crystallization, melting performance, and dispersion properties of the PA6/Ag nanocomposites were studied using transmission electron microscopy (TEM), thermogravimetric analysis (TG), differential thermal scanning calorimetry (DSC), X-ray diffraction (XRD), and polarized light microscopy (POM). Furthermore, the mechanical and tribological behaviors of as-prepared nanocomposites were evaluated using universal tensile testing, impact testing, and friction testing machines. The results show that Ag-nanoparticles are evenly dispersed in PA6 and decrease in size with increasing Ag content. Whereas the crystallinity increased with increasing Ag content, the crystallization temperature of the nanocomposites did not change significantly. However, the mechanical and tribological properties of the nanocomposites increased compared with pure PA6.

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Liu, Feng Xia, Yong Jia Liu, Hong Li Cai, Jia Shuang Luan, and Mei Zhang. "Preparation and Mechanical Properties of Zein/PVA Nanofibrous Membranes." Advanced Materials Research 466-467 (February 2012): 391–95. http://dx.doi.org/10.4028/www.scientific.net/amr.466-467.391.

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This paper describes the morphology and mechanical properties of novel electrospun zein based fibrous membranes. From the results, due to adding PVA, it was found that the electrospun fibers of zein can turn into a new strong membrane. The fibrous membranes were characterized by tensile testing, scanning electron microscopy(SEM) and differential scanning calorimetry(DSC). Effect of PVA was analyzed as one of the most significant factors affecting the mechanical characterization of fibrous membranes. The compatibility of zein/PVA nanofibrous were also analyzed by using DSC method.

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Baimark, Yodthong, and Sumet Kittipoom. "Influence of Chain-Extension Reaction on Stereocomplexation, Mechanical Properties and Heat Resistance of Compressed Stereocomplex-Polylactide Bioplastic Films." Polymers 10, no. 11 (November 2, 2018): 1218. http://dx.doi.org/10.3390/polym10111218.

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Stereocomplex polylactide (scPLA) films were prepared by melt blending of poly(l-lactide) (PLLA) and poly(d-lactide) (PDLA) with and without an epoxy-based chain extender before compression molding. The obtained scPLA films were characterized through differential scanning calorimetry, X-ray diffractometry (XRD), tensile testing and dimensional stability to heat. XRD patterns revealed that all the scPLA films had only stereocomplex crystallites. The obtained results showed that the chain-extension reaction improved mechanical properties of the scPLA films, however, it suppressed stereocomplexation and heat resistance.

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Halász, Katalin, and Levente Csóka. "Plasticized Biodegradable Poly(lactic acid) Based Composites Containing Cellulose in Micro- and Nanosize." Journal of Engineering 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/329379.

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The aim of this work was to study the characteristics of thermal processed poly(lactic acid) composites. Poly(ethylene glycol) (PEG400), microcrystalline cellulose (MCC), and ultrasound-treated microcrystalline cellulose (USMCC) were used in 1, 3, and 5 weight percents to modify the attributes of PLA matrix. The composite films were produced by twin screw extrusion followed by film extrusion. The manufactured PLA-based films were characterized by tensile testing, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), wide angle X-ray diffraction (WAXD), and degradation test.

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Sabbah, Raphaël, and Aaron Rojas Aguilar. "Étude thermodynamique des trois isomères de l'acide chlorobenzoïque. Partie II." Canadian Journal of Chemistry 73, no. 9 (September 1, 1995): 1538–45. http://dx.doi.org/10.1139/v95-191.

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Our isoperibol rocking-bomb calorimeter, previously described, has been modified to: (i) reduce and stabilize the heat exchange between the calorimetric system and its surroundings; (ii) change its thermometer; (iii) associate with it a computer program for the robotics of different steps of an experiment, data acquisition, and determination of the thermodynamic quantities. After testing these modifications and calibrating the calorimetric system, the enthalpies of formation in the condensed state and at 298.15 K of the three isomers of chlorobenzoic acid have been determined by combustion calorimetry. Associating these values with those of their enthalpies of sublimation previously measured, we determined their enthalpies of formation in the gaseous state. The experimental values of the thermodynamic functions [Formula: see text] [Formula: see text] are given for 2-chlorobenzoic acid, 3-chlorobenzoic acid, and 4-chlorobenzoic acid. From the experimental value of the enthalpy of atomization, it has been possible to determine an enthalpy value for the Cb—Cl bond. The experimental and theoretical values of the resonance energy of the three isomers are compatible. The relative stability of some monosubstituted derivatives of benzoic acid studied in our laboratory is also discussed. Keywords: thermodynamics, combustion calorimetry, differential thermal analysis; 2-chlorobenzoic acid, 3-chlorobenzoic acid, 4-chlorobenzoic acid, enthalpies of combustion, of formation, resonance energy, enthalpies of atomization, of intramolecular bonds, reference material.Notre calorimètre isopéribolique à bombe rotative, précédemment décrit, a été modifié: (i) en diminuant et en stabilisant les échanges thermiques entre le système calorimétrique et le milieu extérieur; (ii) en modifiant son thermomètre de mesure; (iii) en lui associant un système informatisé de robotique, d'acquisition et de traitement des signaux thermiques. Après avoir vérifié la bonne marche de l'appareil ainsi modifié et réalisé l'étalonnage du système calorimétrique, nous avons déterminé à 298,15 K et par calorimétrie de combustion les enthalpies de formation à l'état condensé des trois isomères de l'acide chlorobenzoïque. En associant ces valeurs à celles de leurs enthalpies de sublimation à 298,15 K, nous avons pu déterminer leurs enthalpies de formation à l'état gazeux. Les valeurs expérimentales des fonctions thermodynamiques [Formula: see text] [Formula: see text] sont données pour les acides 2-chloro-benzoïque, 3-chlorobenzoïque et 4-chlorobenzoïque. À partir de l'enthalpie d'atomisation expérimentale de ces trois acides, une valeur enthalpique a été proposée pour la liaison Cb—Cl dans ce type de composés. Les valeurs expérimentale et théorique de l'énergie de conjugaison sont compatibles. Une discussion sur la stabilité relative de quelques dérivés monosubstitués de l'acide benzoïque étudiés au laboratoire est aussi développée. Motsclés: thermodynamique, calorimétrie de combustion, analyse thermique différentielle; acide 2-chlorobenzoïque, acide 3-chlorobenzoïque, acide 4-chlorobenzoïque, enthalpies de combustion, de formation, énergie de conjugaison, enthalpies d'atomisation, de liaisons intramoléculaires, substance d'intercomparaison.

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Journal articles on the topic 'Calorimetry testing'

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