Development of reference materials for thermodynamic properties: metrological support of measurements in the field of thermal analysisand calorimetry in Russia

This paper is aimed at analysing the current state and prospects of metrological support and standardisation in the field of thermal analysis in Russia. Main characteristics of reference materials used for testing, graduating, calibrating, and verifying thermal analysis instruments are described.

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Development of Reference Materials for Thermodynamic Properties: Metrological Support of Measurements in the Field of Thermal Analysis and Calorimetry in Russia

Reference Materials in Measurement and Technology ◽

10.1007/978-3-030-32534-3_9 ◽

2020 ◽

pp. 83-89

Author(s):

Andrey M. Nepomiluev ◽

Vyacheslav V. Kazantsev ◽

Artyom P. Shipitsyn

Keyword(s):

Thermal Analysis ◽

Thermodynamic Properties ◽

Reference Materials ◽

Metrological Support ◽

And Calorimetry

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Holographic Polymer-Dispersed Liquid Crystals: Materials, Formation, and Applications

Advances in OptoElectronics ◽

10.1155/2008/684349 ◽

2008 ◽

Vol 2008 ◽

pp. 1-52 ◽

Cited By ~ 56

Author(s):

Y. J. Liu ◽

X. W. Sun

Keyword(s):

Liquid Crystal ◽

Liquid Crystals ◽

Refractive Index Profile ◽

Single Step ◽

Fast Switching ◽

Polymer Dispersed Liquid Crystal ◽

Current State ◽

Index Matching ◽

Polymer Dispersed ◽

Materials Used

By combining polymer-dispersed liquid crystal (PDLC) and holography, holographic PDLC (H-PDLC) has emerged as a new composite material for switchable or tunable optical devices. Generally, H-PDLC structures are created in a liquid crystal cell filled with polymer-dispersed liquid crystal materials by recording the interference pattern generated by two or more coherent laser beams which is a fast and single-step fabrication. With a relatively ideal phase separation between liquid crystals and polymers, periodic refractive index profile is formed in the cell and thus light can be diffracted. Under a suitable electric field, the light diffraction behavior disappears due to the index matching between liquid crystals and polymers. H-PDLCs show a fast switching time due to the small size of the liquid crystal droplets. So far, H-PDLCs have been applied in many promising applications in photonics, such as flat panel displays, switchable gratings, switchable lasers, switchable microlenses, and switchable photonic crystals. In this paper, we review the current state-of-the-art of H-PDLCs including the materials used to date, the grating formation dynamics and simulations, the optimization of electro-optical properties, the photonic applications, and the issues existed in H-PDLCs.

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Toward New High Temperature Reference Materials for Calorimetry and Thermal Analysis

EPJ Web of Conferences ◽

10.1051/epjconf/20147700019 ◽

2014 ◽

Vol 77 ◽

pp. 00019 ◽

Cited By ~ 3

Author(s):

R. Razouk ◽

B. Hay ◽

M. Himbert

Keyword(s):

Thermal Analysis ◽

High Temperature ◽

Reference Materials ◽

Temperature Reference

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Evaluation of sample homogeneity for geochemical standard reference materials used in microanalysis

Journal of Radioanalytical and Nuclear Chemistry ◽

10.1007/bf02055017 ◽

1987 ◽

Vol 110 (1) ◽

pp. 147-158 ◽

Cited By ~ 8

Author(s):

R. H. Filby ◽

S. Nguyen ◽

S. Campbell ◽

A. Bragg ◽

C. A. Grimm

Keyword(s):

Reference Materials ◽

Standard Reference Materials ◽

Materials Used ◽

Sample Homogeneity

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Current State and Outlook for the Development of Instruments for Basic and Metrological Support of the Glonass System

Measurement Techniques ◽

10.1007/s11018-018-1379-4 ◽

2018 ◽

Vol 61 (1) ◽

pp. 1-8

Author(s):

S. I. Donchenko ◽

A. N. Shchipunov ◽

O. V. Denisenko ◽

I. Yu. Blinov ◽

V. N. Fedotov ◽

...

Keyword(s):

Metrological Support ◽

Current State

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Custom 1-D CFD Numeric Model of Single-Cell Scale Sample Holder for Scanning Thermal Analysis

Volume 2: Biomedical and Biotechnology ◽

10.1115/imece2012-89615 ◽

2012 ◽

Author(s):

Logan M. Compton ◽

James L. Armes ◽

Gary L. Solbrekken

Keyword(s):

Thermal Analysis ◽

Heat Capacity ◽

Thermodynamic Properties ◽

Latent Heat ◽

Thermoelectric Module ◽

Experimental Results ◽

Sample Holder ◽

Current Profile ◽

Scanning Calorimetry ◽

Numeric Model

Successful cryopreservation protocols have been developed for a limited number of cell types through an extensive amount of experimentation. To optimize current protocols and to develop effective protocols for a larger range of cells and tissues it is imperative that accurate transport models be developed for the cooling process. Such models are dependent on the thermodynamic properties of intracellular and extracellular solutions, including heat capacity, latent heat, and the physical phase change temperatures. Scanning techniques, such as differential-scanning calorimetry (DSC) and differential thermal analysis are effective tools for measuring those thermodynamic properties. It is essential to understand the behavior of the in house fabricated differential-scanning calorimeter given different cooling and warming rates to reassure and validate the obtained experimental results. A 1-D transient CFD code was created in Matlab using Patankar’s theory to not only validate obtained experimental results but aid in optimizing the control system to produce linear cooling and warming rates. A freezing model was also implemented as a subroutine to numerically observe the effect of heat release and absorption of the sample during a run. The numeric model is composed of a multilayer scheme that incorporates a thermoelectric module which provides the primary temperature control along with the micron sized bridge with sample holder and thermocouple. An electric current profile is imported in from either an experimental run to validate results or from an optimization program to determine the optimum electrical current profile for a desired temperature profile. Numeric detection of heat capacity, latent heat, and thermal resistance has also been demonstrated.

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Investigation of PLA-PEG-45S5 Bioactive Glass Composite Enhancement on Bioactivity

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.833.214 ◽

2020 ◽

Vol 833 ◽

pp. 214-219

Author(s):

Nik Syahirah Aliaa Nik Sharifulden ◽

Siti Noor Fazliah Mohd Noor ◽

Siti Fatimah Samsurrijal ◽

Siti Nur Liyana Ramlee ◽

Nur Syazana Azizan

Keyword(s):

Thermal Analysis ◽

Bioactive Glass ◽

Sol Gel ◽

X Ray Diffraction ◽

Degradation Study ◽

Significant Difference ◽

Biomaterial Science ◽

Materials Used ◽

Hdf Cells

Bioactivity is an important aspect in biomaterial science ensuring materials used are safe for clinical application. The study describes fabrication of composites containing polylactic acid (PLA) – polyethylene glycol (PEG) with incorporation of sol-gel derived 45S5 bioactive glass (BG). Thermal analysis via Differential Thermal Analysis shows a favorable point over degree of crystallization that influence cells attachment, although non-significant difference in values indicates BG has homogenously dispersed. This correlates to X-ray diffraction analysis where non-significant difference is seen in intensities of the diffraction peaks, which confirms low impact of BG brittleness properties over the fabricated composite. Composites’ pH and degradation study in Simulated Body Fluid shows a steady increment profile over time and lower degradation rate for the composite after incorporation of BG. In vitro cell proliferation study also showed that HDF cells seeded on composite film of P/BG2.5 exhibit highest cell viability with steady increment of proliferation throughout the observation period.

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