Thermal management in biological tissue in order to degrade tissue under local heating process

In this study, we reported the results of the design and the fabrication a planar coil in copper (square, a = 10 mm, 15mm high, 90 turns), these planar coils were integrated in a microfluidic chip for trapping magnetic nanoparticles and local heating applications. A small thermocouple (type K, 1 mm tip size) was put directly on top of the micro-channel in poly(dimethyl-siloxane) in order to measure the temperature inside the channel during applying current. The design of planar coils was based on optimizing the results of the magnetic calculation. The most suitable value of the magnetic field generated by the coil was calculated by ANSYS® software corresponded to the different distances from the coil surface to the micro-channel bottom (magnetic field strength Hmax = 825 A/m). The magnetic filed and heating relationship was balanced in order to manipulating the trapping magnetic nanoparticles and heating process. This design of the microfluidic chip can be used to develop a complex microfluidic chip using magnetic nanoparticles.

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Development of a New Finite-Element Method to Analyze Deformation of Plate Due to Line Heating

Journal of Ship Production ◽

10.5957/jsp.2001.17.1.1 ◽

2001 ◽

Vol 17 (01) ◽

pp. 1-7

Author(s):

Seung Il Seo ◽

Yoon Ho Yang ◽

Chang Doo Jang

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Local Heating ◽

Heating Element ◽

Heating Process ◽

Labor Costs ◽

Line Heating ◽

Element Analysis ◽

Energy Principle ◽

Heating And Cooling

The line heating process has been used to create curved surfaces of ship structures. However, because it depends on a worker's skill and experience, it has been a factor in preventing the automation of shipyards and in consuming labor costs. In this paper, to reduce the trial-and-error procedure of line heating work by simulating the deforming process of a plate, a finite-element analysis method is proposed. A new element, called the line heating element, is defined and applied. The line heating element is assumed to have orthotropic material property. Shrinkage forces and moments resulting from line heating are obtained by integration of inherent strains formed by local heating and cooling. The shrinkage forces and moments at the inherent strain region are converted to equivalent nodal forces by the energy principle. Results calculated using the line heating element show good agreement with the results obtained by the commercial finite-element analysis code.

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Mathematical model of local heating hypodermis biological tissue by laser radiation

Visnyk of V.N. Karazin Kharkiv National University, series “Radio Physics and Electronics” ◽

10.26565/2311-0872-2018-29-06 ◽

2018 ◽

Keyword(s):

Mathematical Model ◽

Laser Radiation ◽

Biological Tissue ◽

Near Infrared ◽

Heating Temperature ◽

Local Heating ◽

Internal Heat ◽

Local Area ◽

Heat Propagation ◽

Process Time

Background. Laser radiation is using in medicine for the diagnosis and treatment of many diseases. It is necessary therefore to know processes that occur at the same time. They are studiing for a long time, but not all know now. The problem of interaction of laser radiation with biological targets is important. Objective. The study of thermal processes in the skin and the lower layers when heated by laser radiation, which is introduced in the fiber tissue. Materials and methods. A mathematical model of the heating region inside the process biological tissue continuous and pulsed laser radiation. The radiation is introduced into the tissue by means of optical fiber. Used heat conduction equation in spherical coordinates with internal heat sources. Taken into account the removal of heat from the heated thermal conductivity region of tissue and blood flow. Results. Regimes of heating of biological tissue by continuous laser radiation, single radiation pulses and a series of radiation pulses. It is find the sizes of the heated region, the settling time and temperature gradients. Found the dimensions of the heat regions. They are determined by the fiber diameter, the depth of radiation penetration into the tissue and the speed of heat propagation in tissue. Thermal time constant of the process time is a few minutes. After heating of the pulse radiation at the same rate the fabric cools. Conclusion. To create a need to use laser light blue or green regions of the spectrum a small local area of heating. This radiation penetrates the biological tissue a few millimeters deep. To create large areas of heating should be used near infrared region of the spectrum, where the depth of light penetration into the tissue is equal to a few tens of millimeters. Heating pulse-modulated radiation different from the heating constant output only when the pulse repetition period longer than 1 minute. Then, during the time between pulses cloth cools. Average (smoothed), the heating temperature is the same as when heating a continuous radiation.

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Evaluation of Thermal Damage Impact on Microstructure and Properties of Carburized AISI 9310 Gear Steel Grade by Destructive and Non-Destructive Testing Methods

Materials ◽

10.3390/ma14185276 ◽

2021 ◽

Vol 14 (18) ◽

pp. 5276

Author(s):

Kamil Dychtoń ◽

Andrzej Gradzik ◽

Łukasz Kolek ◽

Krzysztof Raga

Keyword(s):

Local Heating ◽

Fatigue Cracking ◽

Barkhausen Noise ◽

Heating Process ◽

Process Conditions ◽

Case Hardening ◽

Non Destructive Testing ◽

Destructive Testing ◽

Microstructure And Properties ◽

Non Destructive

Advanced aircraft gearboxes operate under high mechanical loads. Currently, aircraft gears are manufactured from chromium–nickel–molybdenum steel grades such as AISI 9310 or Pyrowear 53. The major causes of gear failure are wear and fatigue cracking. As the crack initiation occurs predominantly on the component surface, the gears are routinely subjected to surface hardening processes such as low-pressure carburizing and case hardening. The gears are manufactured in a multiple operation process, in which teeth grinding is a crucial step. Selection of improper grinding conditions can lead to local heat concentration and creation of grinding burns, which are small areas where microstructure and properties changes are induced by high temperature generated during grinding. Their presence can lead to significant reduction of gear durability. Therefore destructive and non-destructive (NDT) quality-control methods such as chemical etching or magnetic Barkhausen noise (MBN) measurements are applied to detect the grinding burns. In the area of a grinding burn, effects related to the over-tempering or re-hardening of the carburized case may occur. In this paper, the results of the studies on the characterization of microstructure changes caused by local heating performed to simulate grinding burns are presented. The areas with the over-tempering and re-hardening effects typical for grinding burns were formed by laser surface heating of carburized AISI 9310 steel. Analyses of the microstructure, residual stresses, retained austenite content, and non-destructive testing by the MBN method were performed. The correlation between the MBN value and the properties of the modified surface layer was identified. It was also found that the re-hardened areas had similar characteristics of changes in the Barkhausen noise intensity, despite the significant differences in the width of the overheated zone, which depended on the laser-heating process conditions.

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Heat dissipation in quasi-ballistic single-atom contacts at room temperature

Scientific Reports ◽

10.1038/s41598-019-55048-3 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Makusu Tsutsui ◽

Yu-Chang Chen

Keyword(s):

Thermal Management ◽

Room Temperature ◽

Heat Dissipation ◽

Phonon Scattering ◽

Local Heating ◽

Atomic Scale ◽

Single Atom ◽

Sinusoidal Voltage ◽

Electron Phonon Scattering ◽

Nonlinear Increase

AbstractWe report on evaluations of local heating in Au single-atom chains at room temperature. We performed onsite thermometry of atomic-scale Au junctions under applied sinusoidal voltage of variable amplitudes. The AC approach enabled to preclude electromigration effects for characterizing the influence of energy dissipations on the lifetime. We elucidated nonlinear increase in the effective temperature of the current-carrying single-atom chains with the voltage amplitudes, which was attributed to subtle interplay between electron-phonon scattering and electron-mediated thermal transport in the quasi-ballistic conductor. We also found that only 0.2% of the electric power contributed to local heating while the majority was consumed at the diffusive bank. The present findings can be used for thermal management of future integrated nanoelectronics.

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Ferroelectric BiFeO3 nanodots formed in non-crystallized BiFeO3 thin-films via a local heating process using a heated atomic force microscope tip

Journal of Sol-Gel Science and Technology ◽

10.1007/s10971-018-4627-9 ◽

2018 ◽

Vol 86 (1) ◽

pp. 170-174 ◽

Cited By ~ 2

Author(s):

Hyun Wook Shin ◽

Jong Yeog Son

Keyword(s):

Thin Films ◽

Atomic Force Microscope ◽

Local Heating ◽

Heating Process ◽

Atomic Force ◽

Bifeo3 Thin Films

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Advances in Microprobe Analysis Applied to Muscle, Nerve and Gland

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100054601 ◽

1982 ◽

Vol 40 ◽

pp. 404-407

Author(s):

T. E. Hutchinson ◽

D. E. Johnson ◽

A. C. Lee ◽

E. Y. Wang

Keyword(s):

Biological Tissue ◽

Microprobe Analysis ◽

Physiological State ◽

External Environment ◽

Physiological Relevance ◽

Muscle Nerve ◽

Technique Development

Microprobe analysis of biological tissue is now in the end phase of transition from instrumental and technique development to applications pertinent to questions of physiological relevance. The promise,implicit in early investigative efforts, is being fulfilled to an extent much greater than many had predicted. It would thus seem appropriate to briefly report studies exemplifying this, ∿. In general, the distributions of ions in tissue in a preselected physiological state produced by variations in the external environment is of importance in elucidating the mechanisms of exchange and regulation of these ions.

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UHV-TEM studies of laser-induced damage

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087471 ◽

1991 ◽

Vol 49 ◽

pp. 632-633

Author(s):

T.S. Savage ◽

R. Ai ◽

D. Dunn ◽

L.D. Marks

Keyword(s):

Surface Science ◽

Rapid Heating ◽

Local Heating ◽

Routine Practice ◽

Transmission Electron ◽

Northwestern University ◽

Laser Induced Damage ◽

Set Up ◽

Focusing Lens ◽

Diffusion Of Impurities

The use of lasers for surface annealing, heating and/or damage has become a routine practice in the study of materials. Lasers have been closely looked at as an annealing technique for silicon and other semiconductors. They allow for local heating from a beam which can be focused and tuned to different wavelengths for specific tasks. Pulsed dye lasers allow for short, quick bursts which can allow the sample to be rapidly heated and quenched. This short, rapid heating period may be important for cases where diffusion of impurities or dopants may not be desirable.At Northwestern University, a Candela SLL - 250 pulsed dye laser, with a maximum power of 1 Joule/pulse over 350 - 400 nanoseconds, has been set up in conjunction with a Hitachi UHV-H9000 transmission electron microscope. The laser beam is introduced into the surface science chamber through a series of mirrors, a focusing lens and a six inch quartz window.

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