Initial Temperature Rise Research Articles

Evaluation of Inactivation Kinetics and Thermodynamic Properties of Peroxidase from Cucumis sativus for Biotechnological and Industrial Applications

The unpurified enzyme gave specific activity of 51.36 μ/mg and thereafter it was subjected to two phases of purification process of salt precipitation and gel filtration. The precipitating agent was ammonium sulphate while Sephadex-G100 served as purification matrix. The purification fold achieved after precipitation and filtration was 3.3 and with corresponding specific activities of 34.22 μ/mg and 116.31 μ/mg. The substrate used for the assay was o-dianisidine. Within 40-80°C of temperature, the kinetics of the peroxidase inactivation was evaluated. The results from assays showed that cucumber peroxidase conformed to the hypothesis of Michealis-Menten Theory. From the Lineweaver-Burk plot, Michaelis Constant (Km) and maximum velocity (Vmax) were evaluated and obtained 5.02mg/ml and 11.57μmol/min respectively. The heat induced inactivation gave biphasic curves, where initial rise in temperature was rapidly succeeded with much slower decrease. A first-order kinetic behaviour was observed for cucumber peroxidase heat inactivation. The k values of between 3.49×10-2 to 8.38×10-2 min-1 was obtained while the Z value was found to be 22.3°C. Decrease in k values with rise in temperature suggests that cucumber peroxidase was rapidly inactivated at elevated temperature. The slope of Arrhenius plot gave the activation energy of 127.99KJMol-1K-1. Also evaluated were thermodynamic constants (ΔH, G Δ, ΔS) for inactivation of peroxidase at variable temperatures. Cucumber peroxidase activity was observed to be pH sensitive and stable within pH range of 5.6-8. Further decrease or increase from this range resulted to decrease in peroxidase stability.

Theoretical simulations on pulsed exciplex pumped Rb vapor laser

A theoretical model is established to describe the laser kinetics and output performance for the pulsed exciplex pumped Rb-Kr laser by combining the rate equations, power propagation equations and thermal conduction equations. Influences of the initial temperature, pump pulse duration and ethane concentration on the output feature and temperature rise are calculated and analyzed. In the long-pulse four-level Rb-Kr XPAL, simulation results show that the optical-to-optical efficiency increases with the rise of initial temperature, but it drops faster due to more heat deposition. In the multi-pulse mode, the quasi-continuous-wave Rb-Kr XPAL with a duty cycle on the order of 10% can be achieved by turning on the pump light when the temperature rise drops to 1/2 of its maximum and switching off when the laser signal decays to 1/e of its maximum. Five-level Rb-Kr modeling shows that the laser output at 780 nm and 795 nm can be observed simultaneously when the pressure of ethane is between 2 torr and 18 torr.

Effects of High-Volume Ground Slag Powder on the Properties of High-Strength Concrete under Different Curing Conditions

Massive high-strength concrete structures tend to have a high risk of cracking. Ground slag powder (GSP), a sustainable and green industrial waste, is suitable for high-strength concrete. We carried out an experimental study of the effects of GSP with a specific surface area of 659 m2/kg on the hydration, pore structure, compressive strength and chloride ion penetrability resistance of high-strength concrete. Results show that adding 25% GSP increases the adiabatic temperature rise of high-strength concrete, whereas adding 45% GSP decreases the initial temperature rise. Incorporating GSP refines the pore structure to the greatest extent and improves the compressive strength and chloride ion penetrability resistance of high-strength concrete, which is more obvious under early temperature-matching curing conditions. Increasing curing temperature has a more obvious impact on the pozzolanic reaction of GSP than cement hydration. From a comprehensive perspective, GSP has potential applications in the cleaner production of green high-strength concrete.

Effects of heat source conditions on the early temperature rise in heated fiber-optic cable emplaced in granulated bentonite mixture

The heated fiber-optic method is receiving much attention as a quality control tool for buffer emplacement in the nuclear waste repository. By heating a fiber-optic cable installed in the buffer material, the thermal conductivity profile along the cable is obtained from which physical parameters such as the dry density at the time of the buffer emplacement and water content afterward can be inferred if carefully calibrated. When the fiber-optic cable is heated, it is known that the initial temperature changes exhibit a time-lapse largely controlled by the properties of the cable. The temperature changes after this initial portion reflect the thermal conductivity of the medium surrounding the cable. In this study, in order to identify how the heat source properties influence the thermal response, heating was numerically simulated for a simplified heat source and a realistic heatable fiber-optic cable. The simulated results showed that the radius and heat capacity of the heat source were the factors that control the time-lapse in the initial temperature rise. For tests with a heating time of 30 or 60 min, it was shown that excluding the initial temperature data from t=0 to about 3–5 min would effectively reduce errors in the thermal conductivity estimation.

Influence of Thermal Effects on the Transport Characteristics of Cellulose Acetate Porous Films

Experimental data have been obtained, and the characteristics of the moisture content and permeability of cellulose acetate porous materials were analyzed via thermal action. Dynamic thermogravimetric analysis found that the destruction process in an air-dry sample of the membrane begins at 21°C. It is accompanied by a 2% weight loss and an endothermic effect. The destruction ends at 50°C. With a subsequent increase in temperature, the manifestation of endothermic effect continues a temperature of 120–175°C with the maximum rate of mass loss at 146°C. The weight loss ends at about 190°C and is 6.5%. The study of MGA-80 and MGA-95 porous cellulose acetate films at transmembrane pressure upon temperature exposure showed that the permeability and specific output flow to water increase as the temperature rises to 50°C. Analysis of dependences of the specific output flow on temperature revealed that the specific output flow to water increases by ~18% upon an initial temperature rise of 10°C. This is due to structural changes in the cellulose acetate layer. A further increase in temperature by 15°C leads to an increase in permeability by ~10%. These phenomena are associated with the process of structural transformation in the active layer and the polymer substrate of the MGA-95 and MGA-80P membranes, respectively.

Effect of initial temperature on explosion characteristics of 2, 3, 3, 3–Tetrafluoropropene

The flammability of refrigerants is a major cause of refrigerant explosion incidents. Studying the explosion characteristics of refrigerants at different initial temperatures can provide significant benefits for solving the safety problems of refrigerants under actual working conditions. This paper studied the effects of the initial temperature and refrigerant concentration on the explosion characteristics of refrigerant 2, 3, 3, 3-tetrafluoropropene (R1234yf) at 0.1 MPa. The curves of explosion characteristics with different initial temperature revealed the same variation trend ranged from 25 °C to 115 °C. Specifically, as the refrigerant concentration was raised, the peak overpressure, the maximum rate of pressure rise, and laminar burning velocity increased initially and decreased afterwards, along with maximum values at the refrigerant concentration of 7.6%. When the refrigerant concentration was 7.6%, the peak overpressure declined exponentially with the initial temperature rise, while the maximum rate of pressure rise increased linearly. The laminar burning velocity calculated from the spherical expansion method indicated that the flame propagation was gradually accelerated by the increase of initial temperature, which coincided with the change of the maximum rate of pressure rise. Meanwhile, experiments and CHEMKIN simulation results demonstrated the effects of elevated temperature from 20 °C to 50 °C on the explosion limits of R1234yf. The lower explosion limit reduced and the upper explosion limit increased with rising initial temperature. In general, R1234yf exhibited moderate combustion and lower explosion risk, compared with traditional refrigerants.

Design and analysis of a novel overload current estimation method for traditional miniature circuit breaker

The power grid is developing towards intelligence. Therefore, as important electrical equipment of the power grid, miniature circuit breaker (MCB) should need to meet the requirements of the smart grid for terminal apparatuses. However, because the bending process of bimetal widely used in MCB overload protection is dispersive, which is difficult to realise electronisation, it is urgent to study the intelligent algorithm of MCB to protect the power grid well. For this purpose, a current calculation method based on temperature rise caused by load current of traditional non-communicable MCB is proposed in this study. Compared with the present current calculation method, there is no iron core saturation problem even in the case of a huge load current. Also, in order to solve the problem of long time delay for stable temperature rise, a recursive algorithm that can rapidly calculate stable temperature rise is proposed. Furthermore, the current can be calculated rapidly. The influence of the initial temperature rise on the current calculation is also taken into account in the proposed algorithm. The simulation and experiment results show that the speed of stable temperature rise obtained by the recursive algorithm can meet the requirement of overload protection, and the error of calculating current is less than 5%.

Parameter Estimation of Inter-Laminar Fault-Region in Laminated Sheets Through Inverse Approach

Estimating the additional power losses caused by an inter-laminar short circuit in electromagnetic devices using thermal measurements depends on many parameters such as thermal conductivity, heat capacity, convective heat coefficient, and size of the fault points. This paper presents a method for estimating these parameters using experimental measurement and a numerical model. The surface temperature rise due to inter-laminar short circuit fault was obtained using an infrared camera. Based on the initial temperature rise method, the least square non-linear approximation technique was used to determine the best fitting parameters of the fault region from the numerical model. To validate the results obtained, the fault region temperature rise and the total loss of the experimental sample were compared with the numerical model using the obtained parameters for different current supply conditions. The study shows that surface temperature distribution can be used to estimate the inter-laminar short circuit fault parameters and localized losses.

MRI-Induced Heating of Coils for Microscopic Magnetic Stimulation at 1.5 Tesla: An Initial Study.

PurposeDeep brain stimulation (DBS) has proved to be effective in the treatment of movement disorders. However, the direct contact between the metal contacts of the DBS electrode and the brain can cause RF heating in magnetic resonance imaging (MRI) scanning, due to an increase of local specific absorption rate (SAR). Recently, micro coils (μMS) have demonstrated excitation of neuronal tissue through the electromagnetic induction both in vitro and in vivo experiments. In contrast to electrical stimulation, in μMS, there is no direct contact between the metal and the biological tissue.MethodsWe compared the heating of a μMS coil with a control case of a metal wire. The heating was induced by RF fields in a 1.5 T MRI head birdcage coil (often used for imaging patients with implants) at 64 MHz, and normalized results to 3.2 W/kg whole head average SAR.ResultsThe μMS coil or wire implants were placed inside an anatomically accurate head saline-gel filled phantom inserted in the RF coil, and we observed approximately 1°C initial temperature rise at the μMS coil, while the wire exhibited a 10°C temperature rise in the proximity of the exposed end. The numerical simulations showed a 32-times increase of local SAR induced at the tips of the metal wire compared to the μMS.ConclusionIn this work, we show with measurements and electromagnetic numerical simulations that the RF-induced increase in local SAR and induced heating during MRI scanning can be greatly reduced by using magnetic stimulation with the proposed μMS technology.

Role of strain-induced martensitic phase transformation in mechanical response of 304L steel at different strain-rates and temperatures

Abstract The strain-rate and temperature dependencies of the strain-induced martensitic phase transformation (MPT) of AISI 304 L are experimentally investigated. Firstly, the tensile tests of 304 L at room temperature are conducted at the strain-rates ranges from 6.67 × 10−4 s-1 to 80 s-1. The stress-strain curves indicate a significant strain-rate effect of the strain-induced MPT, which is closely relevant to extent of the adiabatic heating. The second batch of tensile tests are conducted at several representative strain-rates and at different temperatures ranging from 0 °C to 100 °C. The martensitic volume fractions at different plastic deformation stages are measured by X-ray diffraction to trace the evolution of martensitic phase in the tests. The test results indicate that the environmental temperature and the strain-rate exert coupling influence on the stress-strain behavior. Variations in strength and ductility of 304 L in the tests are explained with a competition mechanism between strain-induced MPT, thermal softening and strain-rate strengthening. A kinetic model of MPT is modified to take the strain-rate, initial temperature and temperature rise into account.

Rice straw addition and biological inoculation promote the maturation of aerobic compost of rice straw biogas residue

Rice straw biogas residue contains high lignin content, so the decomposition of this material by natural compost is slow. This study investigated the effect of the combination of rice straw addition and microbial inoculation (Aspergillus niger CICIMF0410 and Phanerochaete chrysosporium AF96007) on the physiochemical properties of rice straw biogas residue in the composting process. Four composting treatment groups were designed: rice straw biogas residue (RR; T1), RR + rice straw (RS) (T2), RR + inoculants (T3), and RR + RS + inoculants (T4). The addition of rice straw significantly accelerated the initial temperature rise during composting, and microbial inoculation accelerated lignocellulose decomposition. After composting, the electrical conductivities of samples T1 to T4 were 1.22, 0.87, 0.99, and 0.82 DS ml−1, respectively. Compared with other treatment samples, T4 showed noticeably increased degradation rates of HC, CL, and ADL after decomposition. The total humic acid levels of samples T1 to T4 were 9.5, 12.7, 10.5, and 18.6%, with humification index values of 1.45, 1.80, 1.69, and 2.46, respectively, after maturation. After 12 weeks of composting, T4 showed the highest increase in total nitrogen (37.6%), phosphorus (33.6%), and potassium (29.8%) levels. Furthermore, compared with other treatment samples, T4 showed the best maturity indices, such as morphology, color, and odor. Rice straw addition and biological inoculation for biogas residue composting not only significantly decreases the time required for decomposition but also eliminates the toxicity risk for crops and improves the stability of the biogas residue fertilizer.

Heat Exchanger Network Thermal Analysis Using Hybrid Pinch Technology

This research employs hybrid pinch analysis method to evaluate the heat exchanger network (HEN) of an existing refining plant for thermal design bottlenecks. The pinch rules and thermodynamic models were used to analyze the existing network design using available heat flow data to and from each cascade to determine the pinch temperature on incremental heat changes. The pinch point was discovered at the 6^th and 7^th temperature interval corresponding to a process pinch of 188°C with temperature above and below pinch at 193°C and 183°C respectively. The temperature profile showed two distinct regimes: exponential and linear trend lines within 0°C and 110°C which indicated an initial uneven temperature rise that later stabilized with increment proportional to the heat flow quantity within the heat exchanger with time. Furthermore, the temperature of the crude after it passed through the preheat exchanger network in the base case was found to be 242°C but through the retrofit method 275°C was achieved resulting in 33°C temperature differential. By this approach, the base case number of heat exchangers and trains were reduced from 36 and 20 to 30 and 10 respectively and an energy saving of about 19255KJ was achieved for each second the plan was operated.

Effects of Transverse Jet Parameters on Flame Propagation and Detonation Transition in Hydrogen–Oxygen–Argon Mixture

ABSTRACT Two-dimensional numerical simulation is performed with the open-source program AMROC to study the effects of transverse jets (act as fluidic obstacles within a detonation tube) on the flame acceleration and deflagration to detonation transition (DDT). The slot transverse jets have been studied and compared with conventional solid obstacles in tubes. The jet initial parameters, such as mixture composition, stagnation temperature, pressure, and mass flow rate, are investigated. The results demonstrate that a hydrogen-oxygen-argon reactive fluidic obstacle leads to the shortest DDT distance and time compared with solid obstacles and fluidic obstacles composed of pure oxygen or argon. The fluidic obstacles can induce more vorticities to accelerate flame propagation. The DDT distance and time decrease with the jet initial temperature, pressure, and mass flow rate rise, while a high jet initial stagnation temperature is counterproductive to shorting DDT distance and time. The local static pressure rise plays an important role in flame acceleration when increasing the initial pressure of the fluidic obstacle. Higher jet pressure and a wider jet induce more compression waves, which can make the initial flame front more unstable and accelerate the flame as well.

Initial results from the hotspot detection scheme for protection of plasma facing components in Wendelstein 7-X

Abstract One of the main aims of Wendelstein 7-X (W7-X), an advanced stellarator, is to investigate the quasi-steady state operation of magnetic confinement devices for nuclear fusion, for which power exhaust is an important issue. A dominant fraction of the energy leaving from the confined plasma region will be removed by 10 so-called island divertor units, which are designed to sustain a maximum heat flux of up to 10 MW m − 2 . An essential prerequisite for the safe operation of a steady-state device is automatic detection of hot spots and other abnormal events. Simple temperature limits in infrared (IR) thermographic images will not be enough on their own, because of plasma-generated surface coatings and other effects summarized in the following. To protect divertor elements from overheating, and to monitor power deposition onto the divertor elements, near real-time hotspot detection algorithms for the analysis of carbon plasma facing components (PFCs) were implemented and tested in the GLADIS facility. One of the difficulties in hotspot detection in a carbon-based machine is the deposition of plasma impurities as layers with a reduced thermal connection to the underlying bulk material. We have developed and successfully tested a method to classify surface layers and benchmarked the performance of the method with the Tore Supra IR data operating with actively cooled carbon PFCs. The surface layers can be detected in a steady plasma discharge during the initial rise and decay in temperature when a strike line touches parts of the divertor or wall. It can also be detected by modulating electron cyclotron resonance heating (ECRH) input power. This feature allows detection of overheated areas while reducing false positives. For the recent operational campaign, inertially cooled test divertor units (TDU) were installed to prepare for steady-state operation with water-cooled divertor units. Automatic, near real-time detection of hot spots and identification of surface layers in the W7-X divertor are presented. Results are compared with a best fit estimate of the heat transmission coefficient α which is used to calculate heat flux onto the divertor in the presence of surface layers.

Thermographic Measurement and Simulation of Power Losses Due to Interlaminar Contacts in Electrical Sheets

Ferromagnetic cores of electrical machines and transformers are constructed from laminated electrical sheets to reduce eddy current losses. Burrs are formed at the edges of electrical sheets during punching and cutting. These burrs deteriorate the insulation of adjacent sheets, make interlaminar contacts and cause interlaminar currents to flow across the stack. It is essential to know the interlaminar conductivity and the size of the contacts to estimate additional losses in the electrical machine. In this paper, the size of the interlaminar contacts formed by the burrs is estimated using a novel thermographic measurement method and an analytical method. The initial temperature rise of the contacts is used in the analytical model to estimate the contact size. The electromagnetic and thermal finite element formulations validate the results obtained from the analytical method. Moreover, the results obtained from the measurement, the analytical method, and the finite element method are compared. The study shows that the initial temperature rise method can be used to estimate the interlaminar contact size and electromagnetic losses if the temperature is measured immediately after energizing the sheets.

Automotive Fuel Cell Subzero Cold-Starts in a Single Cell Quasi-Adiabatic Fixture

Proton exchange membrane fuel cells (PEMFC) mirror current amenities available from the internal combustion engine such as: rapid start-up time, refueling time, and travel range. For an automotive PEMFC stack to attain 80 kW of power, typically greater than 300 repeat cells are required. A single cell is comprised of 7 layers between the anode and cathode flow fields/current collectors and include layers of macro/microporous diffusion media, ionomer bound carbon supported platinum catalyst layers, and a central proton exchange membrane (PEM). In the presence of partially humidified fuel and oxidant feeds (H2 and 21%O2/79%N2 on the anode and cathode, respectively) energy is produced under applied load as electrons and protons are formed from H2 oxidation on the anode and water is formed by the exothermic reduction of the protons and electrons with O2 on the cathode. The hygroscopic PEM inherently retains humidified reactant gas and oxygen reduction reaction product water which facilitates proton conduction. Four main issues limit commercial viability of automotive fuel cells – (i) cathode catalyst durability, (ii) fuel cell cost, (iii) subzero cold-starts, and (iv) refueling infrastructure. Automotive subzero cold-starts are challenging due to residual water inventory of the PEMFC and product water formation and retention. Water retained within the ionomer of the membrane and catalyst layers partially remains in a liquid phase above -40°C due to pore size and acidity induced freezing point depression.1 For successful cold-start, the temperature of the PEMFC must increase above 0°C before the accumulation of product water in the cathode catalyst layer significantly restricts O2 mass transport. Catalyst layer fabrication affects the water storage capacity of the PEMFC at subzero temperatures. Directly spraying the cathode catalyst layer on the membrane vs. decal transfer of a screen printing results in a nearly 60 mV increase in the initial on load voltage that would translate to a high initial power output, but a 2-2.5x decrease in the water storage capacity at -20°C.2 Partially dehydrating the PEMFC to lower initial water contents (λinitial) increases that water storage capacity at the expense of the initial on load voltage.3 A prototype quasi-adiabatic cold-start single cell PEMFC fixture was designed in-house to address several of the initial issues found in UTRC’s4 original design. The insulating materials selected for permeability and mechanical stability were polycarbonate and balsa wood, respectively. Internal Kapton heaters were used to emulate adjacent cell heading. Figure 1 show the impact of λinitial of 3.2 and 6.2, heater output levels equivalent to 1x and 2x adjacent cell heating (to compensate for non-adiabatic losses), and constant current (600 mV cm-2) vs. constant potential (0.1V) starts. The initial temperature rise increased with higher λinitial and under constant potential control. Isothermal water fill tests were performed on the same membrane electrode assembly after cold starts. Performance degradation due to subzero testing was higher for isothermal water fill tests compared to cold starts. Balliet, R.J. and J. Newman, 'Cold Start of a Polymer-Electrolyte Fuel Cell I. Development of a Two-Dimensional Model', J. Electrochem. Soc., 2011, 158, B927.Pistono, A. and C.A. Rice, 'The Effect of Material Properties on the Subzero Water Storage Capacity of Cathode Catalyst Layers for Proton Exchange Membrane Fuel Cells', J. Electrochem. Soc., 2017, 164, F582.Pistono, A. and C.A. Rice, 'Subzero Water Storage Capacity in Proton Exchange Membrane Fuel Cells: Effects of Preconditioning Method', The Journal of Power Souces, 2018 Under Review.Rice-York, C., J. Needham, N. Gupta, and P.L. Hagans, 'Platform for Rapid Prototyping of PEM Fuel Cell Designs with Enhanced Cold-Start Performance and Durability', ECS Transactions, 2006, 1, 383. Figure 1

Mechanical and microstructural changes of cheese cracker dough during baking

Baked food snacks constitute an important market as a popular consumer product. The mechanical properties of cheese cracker dough at different stages of baking have been investigated as they can relate to the product's texture. The change in mechanical properties during baking was measured whilst the corresponding changes in microstructure were recorded using cryo-SEM at several interrupted baking conditions. The initial modulus of the dough increased with baking time due to starch melting or gelatinisation, melting of fat globules and evaporation of water. Simultaneously gas cells were found to begin forming. The data derived from the uniaxial compression, tension and shear experiments showed that the dough exhibited a rate dependent behaviour at all stages of baking with a power law index of approximately 0.2. Rheometric tests under dynamic heating conditions were also performed and it was found that the modulus decreased significantly, from 150 kPa to 10 kPa, with the initial rise in temperature. This study provides useful data for understanding the evolution of microstructure and rheology during the baking process and its impact on the texture of the final product.

Anisotropy of fatigue behavior and tensile behavior of 5A06 aluminum alloy based on infrared thermography

The fatigue behavior during high cycle fatigue testing and the tensile behavior of 5A06 aluminum alloy considering the anisotropy were studied. Two types of specimens including longitudinal specimen (parallel to the rolling direction) and transverse specimen (perpendicular to the rolling direction) were prepared. Infrared thermography was employed to monitor the temperature evolution during the fatigue and tensile tests. The temperature evolution curves in the two directions were contrastively analyzed. It is found that the temperature evolution during fatigue process possesses four stages: initial temperature rise stage, slow temperature decline stage, rapid temperature rise stage, and finial temperature decline stage. The heat generating mechanisms of the four stages are discussed. Obvious differences can be found between the longitudinal specimen and transverse specimen in fatigue strength and fatigue life. The fatigue strength and fatigue life of longitudinal specimen are higher than those of transverse specimen. During the tensile and fatigue testing process, the fracture temperature in the transverse direction are higher than that in the longitudinal direction. The fatigue strength prediction by means of infrared thermography has a good consistency with that by the traditional method.

Modeling and verification of three-dimensional simulation for BWR in-vessel core degradation

A Multifunction Model has been developed for describing BWR in-vessel core degradation from initial cladding temperature rise to eventual molten materials accumulation in the lower part of reactor vessel as a fundamental safety research by Regulatory Standard and Research Department, Secretariat of Nuclear Regulation Authority (S/NRA/R). The Multifunction Model aims to reduce the uncertainties of severe accident assessment related to physical models on core damage progression, melt formation and material relocation processes in the reactor vessel. The Multifunction Model consists of a thermal-hydraulic module, a fuel pin behavior module and a neutronic module with three-dimensional geometry. For reducing the uncertainties, the thermal-hydraulic module incorporated multi-phase, multi-component and multi-velocity field with multiple chemical and eutectic reactions. Four fuel failure models were incorporated into the fuel pin behavior module in order to simulate the failures of cladding rupture, brittle fracture, cladding melting and pellet dissolution. In order to decrease the calculation time, the data table of macroscopic cross-section was prepared for neutronic diffusion calculation of three fuel conditions in advance. The verification results revealed that the Multifunction Model demonstrated a reasonable capability to simulate the BWR in-vessel core degradations. The validation will be carried out for existing severe accident experiments.

Microscale temperature and SAR measurements in cell monolayer models exposed to millimeter waves.

Due to shallow penetration of millimeter waves (MMW) and convection in liquid medium surrounding cells, the problem of accurate assessment of local MMW heating in in vitro experiments remains unsolved. Conventional dosimetric MMW techniques, such as infrared imaging or fiber optic (FO) sensors, face several inherent limits. Here we propose a methodology for accurate local temperature measurement and subsequent specific absorption rate (SAR) retrieval using microscale thermocouples (TC). SAR was retrieved by fitting the measured initial temperature rise to the numerical solution of an equivalent thermal model. It was found that the accuracy of temperature measurement depends on thermosensor size, that is, the smaller TC, the more accurate the temperature measurement. SAR determined using TC with lead diameters of 25 and 75 μm demonstrated 98.5% and 80.4% match with computed SAR, respectively. However, both TC provided the same temperature rises in long run (> 10 min). FO probe failed to measure adequately local heating both for short and long exposures due to the relatively large size of the probe sensor (400 μm) and time constant (0.6 s). Calculated SAR in the cell monolayer was almost two times lower than that in the surrounding liquid. It was shown that the impact of the cell monolayer on heating due to its small thickness (5 to 10 μm) can be considered as negligible. Moreover, we demonstrated the possibility of accurate measurement of MMW-induced thermal pulses (up to 10 °C) using 25 μm TC. Bioelectromagnetics. 38:11-21, 2017. © 2016 Wiley Periodicals, Inc.