Control Of Sample Temperature Research Articles

A simple cavity-enhanced laser-based heater for reflective samples.

Surface science instruments require excellent vacuum to ensure surface cleanliness; they also require control of sample temperature, both to clean the surface of contaminants and to control reaction rates at the surface, for example, for molecular beam epitaxy and studies of heterogeneous catalysis. Standard approaches to sample heating within high vacuum chambers involve passing current through filaments of refractory metals, which then heat the sample by convective, radiative, or electron bombardment induced heat transfer. Such hot filament methods lead to outgassing of molecules from neighboring materials that are inadvertently heated; they also produce electrons and ions that may interfere with other aspects of the surface science experiment. Hot filaments may even disintegrate when used in the presence of gases introduced to induce surface reactions on the sample. Optical heating using lasers can deliver energy directly to the sample, ensuring that only the sample is heated and surroundings within the vacuum chamber are not, while simultaneously eliminating the need for hot filaments. Despite this advantage, optical heating is not commonly employed-such methods are considered complex, expensive, and unreliable. More fundamentally, surface scientists are often interested in metallic samples, whose reflectivity may limit the efficiency of laser heating. In this paper, we describe a simple and inexpensive sample heater based on a commercial diode laser, whose heating efficiency is enhanced by a concave aluminum mirror placed behind the sample. The geometry of the reflector and sample ensures that a stable optical cavity is produced. Using only 26W of laser power directed to the sample with a fiber optic, a 1-cm diameter × 2-mm thick Pt sample could be heated to 1400K within 1min. Excellent programmable temperature control and long-term temperature stability are also demonstrated. Sample heating to 900 °C was performed with negligible increase in chamber pressure. The entire setup comprises components costing less than typical electron bombardment heaters.

A-319 Capillary Blood Collection for Egg-cellent Reproductive Insights

Abstract Background In the United States, an estimated 13% of women between the ages of 15 and 49 years, experience impaired reproductive potential (fecundity). Assessment of fecundity typically requires an in-person physician visit and venous blood collection to evaluate hormone levels and identify potential reproductive health conditions. Exploring less invasive, at-home sampling options could offer couples insights into their personal reproductive abilities, providing peace of mind and aiding in family planning. Methods Capillary blood, obtained using the Tasso®+ capillary blood collection device coupled with a BD Microtainer® serum tube, was utilized for measurements of analytes associated with female fecundity (follicle stimulating hormone, luteinizing hormone, estradiol, progesterone, anti-Müllerian hormone, and prolactin). These are all FDA-approved assays measured on Roche cobas® e801, assay parameters remained unchanged. Professional and self-collected capillary serum samples were acquired in parallel with the standard venous serum samples, to compare clinical equivalency of the capillary sampling option. In addition to isothermal stability studies at room temperature (20-25°C) and refrigerated (2-8°C) conditions, shipping excursion studies based on ISTA 7D recommendations were performed using a novel packaging solution to control sample temperature and thus, specimen integrity. Studies to assess matrix equivalency, linearity, and imprecision of this alternate sample type were also performed to demonstrate analytical performance. Results Method comparison of venous and professional collection of capillary samples demonstrated correlations (R) ≥ 0.9720 with slopes ranging from 0.919 to 0.971 and mean biases within ±8.2% for all analytes (n = 19-79). Self-collected capillary serum samples demonstrated correlations (R) ≥ 0.9827 with slopes that ranged from 0.841 to 0.985 and mean biases within ±10.7% (n = 16-26). Isothermal stability was demonstrated for each analyte up to 7 days at room temperature and refrigerated conditions. Simulated shipping excursion results were found to be acceptable for both winter and summer conditions with mean biases for each analyte within ±10.2% and ±19.2%, respectively. Matrix equivalency, linearity, and imprecision results adhered to current CLIA acceptance limits for each respective measurement. Conclusions The analytical and stability results affirm the feasibility of collecting capillary serum in a patient-centric manner, providing women with relevant information about their reproductive health.

An automated syringe-based PoC RT-LAMP LFB platform for infectious disease detection from saliva

Decentralized Point-of-Care (PoC) diagnostics hold momentous potential for rapid and accessible viral infection disease detection. Presented is a unique design application of an easy-to-use (plug-and-play) platform for viral detection. The platform leverages a simplified multiplex Reverse-Transcription Loop-mediated Isothermal Amplification (RT-LAMP) Lateral Flow Biosensor (LFB) assay with a lyophilized master mix, eliminating the need for RNA isolation or special reporting equipment. A user-friendly Saliva Measuring Tube (SMT) ensures accurate saliva volume self-collection, and a Syringe-based PoC (SPoC) platform automates sample treatment, reagent mixing, and temperature control using readily available components and consumables. The platform’s performance was evaluated by multiplexed detection of the SARS-CoV-2 N2 target gene and human ACTB gene from saliva samples. The SPoC platform achieved a detection limit of spiked 500 copies/mL for SARS-CoV-2 and consistent internal control readout. The presented PoC system offers a promising initial step for further development toward a decentralized solution for viral infection testing.

Quantitative reaction monitoring using parahydrogen-enhanced benchtop NMR spectroscopy.

The parahydrogen-induced polarisation (PHIP) NMR signal enhancement technique is used to study H2 addition to Vaska's complex (trans-[IrCl(CO)(PPh3)2]) with both standard high-field (9.4 T) NMR and benchtop (1 T) NMR detection. Accurate and repeatable rate constants of (0.84 ± 0.03) dm3 mol-1 s-1 and (0.89 ± 0.03) dm3 mol-1 s-1 were obtained for this model system using standard high-field and benchtop NMR, respectively. The high-field NMR approach is shown to be susceptible to systematic errors associated with interference from non-hyperpolarised signals, which can be overcome through a multiple-quantum filtered acquisition scheme. This challenge is avoided when using benchtop NMR detection because the non-hyperpolarised signals are much weaker due to the lower magnetic field, enabling the use of a simpler and more efficient single RF pulse detection scheme. Method validation against several experimental parameters (NMR relaxation, %pH2 enrichment and temperature) demonstrates the robustness of the benchtop NMR approach but also highlights the need for sample temperature control throughout reaction monitoring. A simple temperature equilibration protocol, coupled with use of an insulated sample holder while manipulating the sample outside the spectrometer, is found to provide sufficient temperature stabilisation to ensure that accurate and repeatable rate constants are obtained. Finally, the benchtop NMR reaction monitoring protocol is applied to the analysis of a complex mixture, where multiple reaction products form simultaneously. H2 addition to a mixture of three Vaska's complex derivatives was monitored, revealing the presence of competitive reaction pathways within the mixture.

A multi-reservoir extruder for time-resolved serial protein crystallography and compound screening at X-ray free-electron lasers

Serial crystallography at X-ray free-electron lasers (XFELs) permits the determination of radiation-damage free static as well as time-resolved protein structures at room temperature. Efficient sample delivery is a key factor for such experiments. Here, we describe a multi-reservoir, high viscosity extruder as a step towards automation of sample delivery at XFELs. Compared to a standard single extruder, sample exchange time was halved and the workload of users was greatly reduced. In-built temperature control of samples facilitated optimal extrusion and supported sample stability. After commissioning the device with lysozyme crystals, we collected time-resolved data using crystals of a membrane-bound, light-driven sodium pump. Static data were also collected from the soluble protein tubulin that was soaked with a series of small molecule drugs. Using these data, we identify low occupancy (as little as 30%) ligands using a minimal amount of data from a serial crystallography experiment, a result that could be exploited for structure-based drug design.

Contributions towards variable temperature shielding for compact NMR instruments.

The application of compact NMR instruments to hot flowing samples or exothermically reacting mixtures is limited by the temperature sensitivity of permanent magnets. Typically, such temperature effects directly influence the achievable magnetic field homogeneity and hence measurement quality. The internal-temperature control loop of the magnet and instruments is not designed for such temperature compensation. Passive insulation is restricted by the small dimensions within the magnet borehole. Here, we present a design approach for active heat shielding with the aim of variable temperature control of NMR samples for benchtop NMR instruments using a compressed airstream which is variable in flow and temperature. Based on the system identification and surface temperature measurements through thermography, a model predictive control was set up to minimise any disturbance effect on the permanent magnet from the probe or sample temperature. This methodology will facilitate the application of variable-temperature shielding and, therefore, extend the application of compact NMR instruments to flowing sample temperatures that differ from the magnet temperature.

Infrared Spectroscopic Investigations of Calcium Oxalate Monohydrate (Whewellite) Dehydration/Rehydration

Variable-temperature infrared spectroscopy is employed to monitor molecular vibrations during dehydration of calcium oxalate monohydrate (COM) and hydration of anhydrous calcium oxalate (COA). A unique variable-temperature infrared spectroscopy approach combines precise sample temperature control and rapid (2 °C s−1) heating/cooling with high-sensitivity infrared analysis. Infrared spectra are obtained at specific isothermal sample temperatures, while applying linear temperature versus time heating and cooling ramps, and in coordination with programmed temperature steps. Spectrum vibration bands provide information regarding the symmetry and local environments of solid-state water molecules and oxalate anions. When COM is heated, water molecules liberated from different crystallographic sites are selectively detected. Subtle oxalate anion configuration changes associated with water losses are detected based on infrared vibration band shapes and wavenumber trends. Dehydration and rehydration processes occur at lower temperatures and over narrower temperature ranges than conventional thermal analysis methods because samples consist of thin layers of small particles. Reversible and irreversible sample changes are distinguished by using a step heating/cooling temperature program and spectral subtractions. COA temperature-dependent structure variations that occur while heating and cooling samples in an atmosphere with a low water vapor concentration are characterized.

Relationship between ambient temperature at sampling and the interferon gamma test result for bovine tuberculosis in cattle

Bovine tuberculosis (bTB) is a disease of significant economic and zoonotic importance, therefore, optimising tests for the identification of Mycobacterium bovis infected cattle is essential. The Interferon Gamma (IFN-γ) Release Assay (IGRA) can diagnose M. bovis infected cattle at an early stage, is easy to perform and can be used alongside skin tests for confirmatory purposes or to increase diagnostic sensitivity. It is known that IGRA performance is sensitive to environmental conditions under which samples are taken and transported. In this study, the association between the ambient temperature on the day of bleeding and the subsequent IGRA result for bTB was quantified using field samples from Northern Ireland (NI). Results of 106,434 IGRA results (2013–2018) were associated with temperature data extracted from weather stations near tested cattle herds. Model dependent variables were the levels of IFN-γ triggered by avian purified protein derivative (PPDa), M. bovis PPD (PPDb), their difference (PPD(b-a)) as well as the final binary outcome (positive or negative for M. bovis infection). IFN-γ levels after both PPDa and PPDb stimulation were lowest at the extremes of the temperature distribution for NI. The highest IGRA positive probability (above 6%) was found on days with moderate maximum temperatures (6–16 °C) or moderate minimum temperatures (4–7 °C). Adjustment for covariates did not lead to major changes in the model estimates. These data suggest that IGRA performance can be affected when samples are taken at high or low temperatures. Whilst it is difficult to exclude physiological factors, the data nonetheless supports the temperature control of samples from bleeding through to laboratory to help mitigate post-collection confounders.

A Device for Temperature Control and Mixing of Biological Samples

A Device for Temperature Control and Mixing of Biological Samples

Streamlined Methods for Processing and Cryopreservation of Cell Therapy Products Using Automated Systems.

Streamlined procedures for processing and cryopreservation of cell therapies using good laboratory practices are integral to biomanufacturing process development and clinical applications. The protocol herein begins with the preparation of human cell types cultured as adherent (i.e., mesenchymal stromal cells, MSCs) or suspension cells (i.e., peripheral blood mononuclear cells, PBMCs) to comprehensively demonstrate procedures that are applicable to commonly used primary cell cultures. Cell processing steps consist of preparing high yields of cells for cryopreservation using instruments routinely used in cell manufacturing, including the Finia® Fill and Finish System and a controlled-rate freezer. The final steps comprise the storage of cells at subzero temperatures in liquid nitrogen vapor phase followed by the analysis of cell phenotypes before and after processing and cryopreservation, along with cell quality metrics for validation. Additionally, the protocol includes important considerations for the implementation of quality control measures for equipment operation and cell handling, as well as Good Laboratory Practices for cell manufacturing, which are essential for the translational use of cell therapies. Key features • The protocol applies to small- or large-scale manufacturing of cell therapy products. • It includes streamlined procedures for processing and cryopreservation of cells cultured as adherent cells (MSCs) and suspension cells (PBMCs). • Provides temperature control and rapid partitioning of sample in cryopreservation solution to maintain high viability of a range of cell types throughout the procedures. • This protocol employs the Finia® Fill and Finish System and a controlled-rate freezer. Graphical overview.

Effects of heat/mass transfer limitations and process exothermicity on the kinetic parameters of the devolatilization and oxidation reactions of wood chars

Thermogravimetric curves of wood char oxidation consist of devolatilization and oxidation, described with a linear and a power-law rate reaction, respectively. The lack of measurement and control of the sample temperature in standard commercial thermogravimetric systems (STGA) can introduce serious deviations from the heating program, originated from heat and mass transfer limitations and reaction exothermicity. This study aims at quantifying the consequent effects on the estimated kinetic constants for beech, fir and spruce wood chars. A first set of measurements is based on a special purpose designed, homemade thermo-analyzer (HMTGA), permitting for an accurate sample temperature control and a rigorous kinetic regime. The second set makes use of a standard commercial thermobalance (STGA). It is found that for heating rates up to 10 K/min spikes in the rate curves disappear for 1 mg samples and the deviations on the activation energies become null or very small (maximum around 1–1.5%), compared with the HMTGA data. However, the order of the oxidation reaction is always lower (by about 15%). Improvements are not observed following further sample mass reduction.

A General Small-Angle X-ray Scattering-Based Screening Protocol for Studying Physical Stability of Protein Formulations.

A fundamental step in developing a protein drug is the selection of a stable storage formulation that ensures efficacy of the drug and inhibits physiochemical degradation or aggregation. Here, we designed and evaluated a general workflow for screening of protein formulations based on small-angle X-ray scattering (SAXS). Our SAXS pipeline combines automated sample handling, temperature control, and fast data analysis and provides protein particle interaction information. SAXS, together with different methods including turbidity analysis, dynamic light scattering (DLS), and SDS-PAGE measurements, were used to obtain different parameters to provide high throughput screenings. Using a set of model proteins and biopharmaceuticals, we show that SAXS is complementary to dynamic light scattering (DLS), which is widely used in biopharmaceutical research and industry. We found that, compared to DLS, SAXS can provide a more sensitive measure for protein particle interactions, such as protein aggregation and repulsion. Moreover, we show that SAXS is compatible with a broader range of buffers, excipients, and protein concentrations and that in situ SAXS provides a sensitive measure for long-term protein stability. This workflow can enable future high-throughput analysis of proteins and biopharmaceuticals and can be integrated with well-established complementary physicochemical analysis pipelines in (biopharmaceutical) research and industry.

Light Intensity Modulated Photo-Electrochemical Methods and Distribution of Relaxation Times As Tools to Investigation Photovoltaic Materials

Electrical Impedance Spectroscopy (EIS, sometimes also Electrochemical Impedance Spectroscopy) found its place in material studies as a routine experiment. EIS proliferation became possible through advances in electronics. Current-voltage characteristics were standard features of potentiostats. Impedance techniques require additional components embedded into a potentiostat, namely signal generator and signal analyzer. Relatively simple devices are available, although dedicated instrumentation with little noise, broad frequency control and perhaps sample temperature control or automated sample handling are particularly desired and command premium in cost.EIS as an electrical technique uses as the perturbing signal alternating electrical signal, either potential of current. In general, impedance studies are intended to study a transfer function and the input and output do not have to be only voltage-current or current-voltage as it would be in EIS. In mechanical engineering are for example useful studies focused on mechanical perturbation. Electrical response by its nature makes EIS amenable to study electrochemical systems.Along with the impedance vs. frequency data collection comes also the need of meaningful data interpretation. This is typically done through data fitting to components of an equivalent electrical circuit. The acquired data -- real and imaginary impedance components gathered over a vast range of frequencies -- are evaluated by fitting to some equivalent circuit using nonlinear regression.Oftentimes both finding the equivalent circuit and the physical component assignment are tedious, if not impossible. Recently a new approach to data reduction has been a treatment via distribution of relaxation times (DRT) [1, 2]. In principle, this approach has been outlined already in 1936 [3]. Its present use was made possible by available computation power of current PCs [4, 5]. While this is not a substitute to equivalent circuits and subsequent physical data interpretation, it is possibly a method, when used appropriately and in automated way, that can provide more information that simple comparison of the Bode or Nyquist graphs. This note is presenting some examples of this approach.In the field of photovoltaic studies of light-gathering materials experimentation on systems responding to illumination makes use of impedance studies in which the perturbing signal is light of certain wavelength (or white light) with variable intensity. Here we will look at the link between EIS and electrical response spectroscopy induced by fluctuating light. This is sometimes for short dubbed as optical spectroscopy although it does make a use of the instruments for optical spectroscopy (such as UV-VIS, IR etc.) as they are known from analytical chemistry literature. Rather, an electric signal in a photoactive material is generated by intensity modulated light at different frequencies (similar range to electrical impedance spectroscopy) and a response (the magnitude and the phase shift) is analyzed. In this respect the magnitude and phase shift correspond to the magnitude and a vector of resistance on the polar plot of electrical impedance measurement. However, the data obtained serve a different purpose. For example, in a photovoltaic shorted system, the time constant associated with the response corresponds to mobility of the photogenerated charge in the material. For an open-circuit potential of such a photovoltaic system the measured time constant response corresponds to the rate of recombination of the generated hole-electron species.Such materials of general structure (ABX3) could be replacements for silicon-based photovoltaic cells. These materials, due to the possible variability of both cations and anions in their composition, offer almost endless possibilities for synthetic preparation. For the active layer of a solar cell is often used the CH3NH3PbI3-2Cl2 perovskite structure, i.e., a structure containing an organic component. We have built and then tested such photovoltaic cells by static and dynamic methods using a unique photoelectric research instrument using the method CIMPS (Controlled Intensity Modulated Photocurrent Spectroscopy).AcknowledgementThis work was supported through the support of The Czech Science Foundation (GACR), contract GA19-23718S.References BioLogic, Distribution of Relaxation Times (DRT): an introduction, BioLogic, Editor. 2017.Weese, J., A reliable and fast method for the solution of Fredhol integral equations of the first kind based on Tikhonov regularization. Computer Physics Communications, 1992. 69(1): p. 99-111.Yager, W.A., The Distribution of Relaxation Times in Typical Dielectrics. Physics, 1936. 7(12): p. 434-450.Shoar Abouzari, M.R., et al., On the physical interpretation of constant phase elements. Solid State Ionics, 2009. 180(14): p. 922-927.Wan, T.H., et al., Influence of the Discretization Methods on the Distribution of Relaxation Times Deconvolution: Implementing Radial Basis Functions with DRTtools. Electrochimica Acta, 2015. 184: p. 483-499.

Quantifying Real-Time Sample Temperature Under the Gas Environment in the Transmission Electron Microscope Using a Novel MEMS Heater.

Accurate control and measurement of real-time sample temperature are critical for the understanding and interpretation of the experimental results from in situ heating experiments inside environmental transmission electron microscope (ETEM). However, quantifying the real-time sample temperature remains a challenging task for commercial in situ TEM heating devices, especially under gas conditions. In this work, we developed a home-made micro-electrical-mechanical-system (MEMS) heater with unprecedented small temperature gradient and thermal drift, which not only enables the temperature evolution caused by gas injection to be measured in real-time but also makes the key heat dissipation path easier to model to theoretically understand and predict the temperature decrease. A new parameter termed as “gas cooling ability (H)”, determined purely by the physical properties of the gas, can be used to compare and predict the gas-induced temperature decrease by different gases. Our findings can act as a reference for predicting the real temperature for in situ heating experiments without closed-loop temperature sensing capabilities in the gas environment, as well as all gas-related heating systems.

Sticking coefficients of selenium and tellurium

The sticking coefficients of selenium and tellurium were measured as a function of temperature. Molecular beams of the chalcogen elements supplied from thermal effusion cells were directed onto a heated quartz crystal microbalance, and the mass gain rate was detected as a function of temperature. Both sticking coefficients were found to sharply drop within a narrow temperature range of 20 and 30 °C from above 0.8 down to about 0.2 at film surface temperatures around 35 and 115 °C for selenium and tellurium, respectively. While the sticking coefficient of tellurium reached zero at temperatures above 150 °C, the sticking coefficient of selenium remained about 0.2 up to a film surface temperature of 60 °C, suggesting that selenium was supplied in different chemical forms. The direct and quantitative determination of the sticking coefficients provides important insights into the kinetics of chalcogenide-based film growth and points toward the need of a precise sample temperature control.

High-pressure small-angle X-ray scattering cell for biological solutions and soft materials.

Pressure is a fundamental thermodynamic parameter controlling the behavior of biological macromolecules. Pressure affects protein denaturation, kinetic parameters of enzymes, ligand binding, membrane permeability, ion trans-duction, expression of genetic information, viral infectivity, protein association and aggregation, and chemical processes. In many cases pressure alters the molecular shape. Small-angle X-ray scattering (SAXS) is a primary method to determine the shape and size of macromolecules. However, relatively few SAXS cells described in the literature are suitable for use at high pressures and with biological materials. Described here is a novel high-pressure SAXS sample cell that is suitable for general facility use by prioritization of ease of sample loading, temperature control, mechanical stability and X-ray background minimization. Cell operation at 14 keV is described, providing a q range of 0.01 < q < 0.7 Å-1, pressures of 0-400 MPa and an achievable temperature range of 0-80°C. The high-pressure SAXS cell has recently been commissioned on the ID7A beamline at the Cornell High Energy Synchrotron Source and is available to users on a peer-reviewed proposal basis.

Development of a method for temperature control of sunflower seeds in determining the content of oleic acid NMR

Processing oil seeds with a modified fatty acid composition requires the development of new ways to control quality indicators. One of the solutions is express control of the mass fraction of oleic acid in oil of sunflower seeds using the NMR method. Production tests of this method showed the necessity for temperature control of samples before analysis for a long time, if the sample of temperature is less than 15 ° C, which significantly increases the analysis time. The article presents data of changing in the weighted average time of spin-spin relaxation of protons contained in sunflower seeds with different mass fractions of oleic acid in seed oil from their temperature. It was found that a decrease in the sample temperature by 1 ° C leads to a decrease in the weighted average time of spin-spin relaxation of protons seeds with a different mass fraction of oleic acid by 2.3 mc. To reduce the time of thermostating of the sample, we proposed the method of SHF-treatment of sunflower seeds. During the tests we identified the optimal energy of SHF-treatment (in our case it was 360 W) for the test sample of 100 g weight. The selected weight of the sample can significantly reduce the influence of the factor of different quality of samples and is minimal to obtain comparable results. SHF-treatment allows uniform heating of samples without evaporation of moisture from their surface and without changing the internal structure of the sample.

Automating ASTM D2983 Low-Temperature Viscosity Measurements

Abstract The low-temperature viscosity of lubricants and hydraulic fluids is a key performance parameter in choosing an appropriate fluid. For gear oils, Automatic Transmission Fluids (ATF), and hydraulic fluids, ASTM D2983 is the primary test method for defining this low-temperature property. This article describes an approach to automatically measure this property for the aforementioned categories of products. It retains the critical aspects of D2983, which are the preheating, thermal conditioning from room temperature to test temperature, viscometer, rotor, and viscosity measurement criteria. Thermal conditioning follows that described in Annex 2 of D2983, and when complete, the viscosity is automatically measured. This requires a digital rotational viscometer with the capability to record viscosity and temperature as a key element in making the needed measurements. As described in D2983, viscosity measurements are made at discrete shear rate intervals (spindle speeds) for a set period of time. Upon the completion of a test, the data file contains a history of the thermal conditioning (time and temperature), plus the viscosity and torque at each spindle speed. By automating the procedure, the sample is undisturbed from the start of the test until the viscosity measurements begin. This eliminates errors due to sample preparation and temperature control throughout the test. Since the spindle is immersed in the sample throughout the test, the viscosity is measured on an undisturbed sample. All of this results in consistent thermal conditioning and a controlled temperature during viscosity measurement and eliminates operator-induced variance. Data on ASTM Proficiency Test Program samples and other commercial products indicate significant improvement in precision. The samples evaluated include ATF, automotive gear oils, and other products. An abbreviated procedure is described that could be suitable for some samples. This is achieved by shortening the soak time at the test temperature, but following the same thermal conditioning process prior to the soak at the test temperature.

Assessment of quality of products from polymer materials for machine-building purposes

This paper presents the results of research of the contact method of volumetric temperature control of a polymer sample. The scheme of thermocouples (TC) location in a polymer sample, finite-element model and general mathematical model for calculating the influence of the quantity of thermocouples on heating samples at high-frequency processing are constructed. Comparative analysis of the obtained results was conducted.

Contact method of volume control of temperature of a polymer sample at high-frequency heating

This paper presents the results of research of the contact method of volumetric temperature control of a polymer sample. The scheme of thermocouples (TC) location in a polymer sample, finite-element model and general mathematical model for calculating the influence of the quantity of thermocouples on heating samples at high-frequency processing are constructed. Comparative analysis of the obtained results was conducted.