To determine the differences in thermal effects on vocal folds between four fiber-routed lasers.
In this experimental laboratory study the thermal effects of an AcuPulse Duo CO2 (CO2 AP), UltraPulse ...Duo CO2 (CO2 UP), KTP, and Blue laser were analyzed using a Schlieren technique on a human tissue mimicking gel model. Power, laser duration, laser fiber distance to tissue and mode (continuous wave CW vs pulsed P modes) were evaluated in varying combinations in order to compare the effects of the tested lasers and to explore the individual effect on thermal expansion and incision depth of each setting. The model was validated by comparing the results from the Schlieren model with histology of ex vivo fresh human vocal folds after laser irradiation using a selection of the same laser settings, and calculating the intraclass correlation coefficient (ICC).
One thousand ninety-eight Schlieren experiments and 56 vocal cord experiments were conducted. In comparison with CW mode, less thermal expansion occurred in P mode in all lasers, while incisions were deeper in the CO2 and more superficial in the KTP and Blue lasers. The mean thermal expansion was found to be minimally smaller, whereas incision depth was pronouncedly smaller in the KTP and Blue compared to the CO2 lasers. Duration of laser irradiation was the most important factor of influence on thermal expansion and incision depth for all lasers in both CW and P modes. The ICC for consistency between the results of the Schlieren model and the vocal cord histology was classified from fair to excellent, except for the thermal expansion of the Blue laser, which was classified as poor.
This study demonstrates important differences in thermal effects between CO2, KTP, and Blue lasers which can be explained by the different physical characteristics of the P modes and divergence of the fiber delivery system. The Schlieren imaging model is a good predictor of the relative thermal effects in vocal fold tissue. Our results can be used as a guidance for ENT surgeons using fiber-routed lasers, in order to achieve effective treatment of vocal fold lesions and prevention of functional impairment of vocal folds.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Recent developments in the theory of pure neutron matter and experiments concerning the symmetry energy of nuclear matter, coupled with recent measurements of high-mass neutron stars, now allow for ...relatively tight constraints on the equation of state of dense matter. We review how these constraints are formulated and describe the implications they have for neutron stars and core-collapse supernovae. We also examine thermal properties of dense matter, which are important for supernovae and neutron star mergers, but which cannot be nearly as well constrained at this time by experiment. In addition, we consider the role of the equation of state in medium-energy heavy-ion collisions.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Convective thermal metamaterials are artificial structures where convection dominates in the thermal process. Due to the field coupling between velocity and temperature, convection provides a new ...knob for controlling heat transfer beyond pure conduction, thus allowing active and robust thermal modulations. With the introduced convective effects, the original parabolic Fourier heat equation for pure conduction can be transformed to hyperbolic. Therefore, the hybrid diffusive system can be interpreted in a wave‐like fashion, reviving many wave phenomena in dissipative diffusion. Here, recent advancements in convective thermal metamaterials are reviewed and the state‐of‐the‐art discoveries are classified into the following four aspects, enhancing heat transfer, porous‐media‐based thermal effects, nonreciprocal heat transfer, and non‐Hermitian phenomena. Finally, a prospect is cast on convective thermal metamaterials from two aspects. One is to utilize the convective parameter space to explore topological thermal effects. The other is to further broaden the convective parameter space with spatiotemporal modulation and multi‐physical effects.
Providing a new knob for controlling heat transfer, convective effects have gained significant interest in the design of thermal metamaterials. With the introduced efficient, directional, and wave‐like heat transfer, many novel phenomena are observed in dissipative regime. The state‐of‐the‐art advancements in this emerging field are brought under the same umbrella, and a future perspective on promising directions is provided.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Synergistic therapy for malignant tumors has been developed in the past. However, several disadvantages that are associated with the applied inorganic nanoagents cannot be avoided, including ...intrinsic systemic toxicity, immunosuppression, and low therapeutic efficiency. Herein, a biocompatible, multifunctional, inorganic nanoagent that simultaneously integrates chemodynamic, starvation, and photothermal therapies is developed. This nanoagent effectively converts endogenous H2O2 into highly toxic hydroxyl radicals via the Fenton reaction. Self‐reinforced cancer therapy is achieved via the scavenging of intracellular glutathione and glucose. The encapsulation of nanoagent by erythrocytes drastically reduces its immune recognition by macrophages. Thus, an augmented anti‐tumor immune response is realized. Moreover, in contrast to traditional inorganic chemodynamic nanomaterials, the nanoagent has outstanding photothermal efficiency. Therefore, the present system exhibits an effective tumor therapeutic outcome. This work may facilitate a new pathway for the development of highly efficacious synergetic therapies.
A type of multifunctional nanoagents with outstanding photothermal effects and superb chemodynamic performance is developed. In this system, the encapsulation of nanoagents by erythrocytes drastically reduces its immune recognition by macrophages. The augmented anti‐tumor immune response further promotes the effective therapy of deep‐tissue cancers.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
This paper focuses on experimental investigations on the kinematic and thermal aspects of the propagative plastic instabilities, namely Lüders band and Portevin–Le Châtelier (PLC) band, observed in a ...medium Mn transformation-induced plasticity (TRIP) steel. The full-field strain and heat source measurements are used concurrently to investigate in-situ the propagative bands. The kinematic analysis provides the real-time strain field evolution allowing the observation and quantification of the band nucleation and propagation. The local Lüders strain is demonstrated both space and time independent, and its magnitude is equivalent to the macroscopic Lüders strain. The spatio-temporal independent characteristic is also verified on the local strain in the PLC bands. Concerning the thermal field analysis, the heat sources are estimated and used to obtain the geometrical and dynamic parameters of the propagating bands, including the band width, orientation, propagation velocity, and appearance moment. Then the estimated heat sources are applied to establish an experimental energy balance during the plastic deformation. The quantitative energy analysis reveals that the strain-induced martensitic transformation takes place in the Lüders band but barely in the PLC bands. The ex-situ X-ray diffraction measurement on the phase content and surface hardness testing of the material confirm well this determination.
Display omitted
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
In this paper, a multi-segment bonded crystal model of YAG/Tm:YAG/ YAG/Tm:YAG/YAG structure is proposed firstly and the thermal effect of LD double-end pumped multi-segment bonded Tm:YAG crystal is ...investigated. The thermal distribution is simulated and the thermal focal length of the multi-segment bonding is calculated and measured, which confirms that it can effectively alleviate the thermal effect. In experiment, when the absorbed power is 26 W the laser with a center wavelength of 2014.52 nm and an output power of 8.27 W is obtained, simultaneously optical-to-optical conversion efficiency is 31.8% and the slope efficiency is 38%.
•In this paper, a multi-segment bonded crystal model of YAG/Tm:YAG/ YAG/Tm:YAG/YAG structure is proposed firstly and the thermal effect of LD double-end pumped multi-segment bonded Tm:YAG crystal is investigated.•The thermal distribution is simulated and the thermal focal length of the multi-segment bonding is calculated and measured, which confirms that it can effectively alleviate the thermal effect.•In experiment, when the absorbed power is 26 W, the laser with a center wavelength of 2014.52 nm and an output power of 8.27 W is obtained, simultaneously optical-to-optical conversion efficiency is 31.8% and the slope efficiency is 38%.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Microwave vacuum evaporation (MVE) is a promising alternative to conventional methods. However, the mechanisms underlying its efficiency remain elusive. In this study, the effects of microwaves on ...glucose solutions were investigated via molecular dynamics (MD) simulations and experimental studies to elucidate possible microwave non-thermal and thermal effects, respectively. MD simulations on energy-related parameters, interfacial properties, and molecular migration indicated that a microwave electric field of 105 V/m could not influence water evaporation behavior at a constant temperature of 90 °C, validating the absence of non-thermal effects in the MVE of glucose solutions. Meanwhile, superheating was not observed in this study during microwave heating at atmospheric pressure or in vacuum. High-intensity microwaves enabled the solution to reach its boiling point rapidly and remarkably induced an intensified film boiling during MVE, thereby shortening the evaporation time. Therefore, the high efficiency of MVE may be attributed to the thermal effects of strong microwaves.
•Thermal effects and possible non-thermal effects during MVE were studied.•Non-thermal effects were not observed during microwave evaporation at 105 V/m.•109 V/m-z and 109 V/m-x microwaves accelerated and impeded evaporation, respectively.•Superheating did not occur during microwave heating with solution agitation.•Thermal effects of strong microwaves raised heating rate and intensified boiling.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This paper presents the influence of temperature on the residual strength by analyzing shearing tests carried out in a temperature- and velocity-controlled ring shear apparatus. Temperature was ...applied in steps of cooling and heating ranging between 6 °C and 50 °C at a constant shearing velocity of 0.442 mm/min. Additional tests include the evaluation of the strength at 0.890 mm/min before and after the imposed temperature change. Six basic soil types characterized by different mineralogy, grain size and plasticity, as well as, mixture soils having different proportions of sand and clay, are evaluated and the results are interpreted in terms of their properties. The experimental results reveal that the temperature effect becomes relevant when fine particles and plasticity increase being negligible in the case of the sandy soil. Shear strength reacts immediately to temperature changes and a new residual strength establishes soon. The temperature effect is symmetric. An increase in temperature leads to a decrease in strength, and an equal and opposite trend is observed when temperature decreases. The magnitude of the strength variation is significant in clayey soils. For the case of high plasticity soils, the residual friction angle variation observed during cooling and heating (±50 °C) is around 2°. The strain rate effect evaluated in a smaller number of tests indicated a strain rate strengthening in all the materials tested except for the case of the sandy soil, which also was not reactive to temperature changes. The experiments are calibrated with a velocity, state, and temperature-dependent friction model.
•Influence of temperature on residual shear strength have been characterized.•Heating leads to decrease in friction and cooling leads to an increase for high shearing rates.•Relevance of residual friction change with respect of temperature correlates with the soil plasticity.•No effect of temperature was measured for the clean sand tested.•The friction constitutive model developed by Chester (1994) can reproduce the tests performed.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
PDF
