Journal articles: 'Mechanical ablation'

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Nijland, Hendricus, Jinwen Zhu, Thomas C. Kwee, Ding-Jun Hao, and Paul C. Jutte. "Mechanical bone strength decreases considerably after microwave ablation–Ex-vivo and in-vivo analysis in sheep long bones." PLOS ONE 18, no. 10 (October 12, 2023): e0292177. http://dx.doi.org/10.1371/journal.pone.0292177.

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Background Bone metastases are on the rise due to longer survival of cancer patients. Local tumor control is required for pain relief. Microwave ablation (MWA) is a technique for minimally invasive local tumor treatment. Tumor tissue is destroyed by application of local hyperthermia to induce necrosis. Given the most common setting of palliative care, it is generally considered beneficial for patients to start mobilizing directly following treatment. No data on mechanical strength in long bones after MWA have been published so far. Materials and methods In- and ex-vivo experiments on sheep tibias were performed with MWA in various combinations of settings for time and power. During the in-vivo part sheep were sacrificed one or six weeks after ablation. Mechanical strength was examined with a three-point bending test for ablations in the diaphysis and with an indentation test for ablations in the metaphysis. Results MWA does not decrease mechanical strength in the diaphysis. In the metaphysis strength decreased up to 50% six weeks after ablation, which was not seen directly after ablation. Conclusion MWA appears to decrease mechanical strength in long bone metaphysis up to 50% after six weeks, however strength remains sufficient for direct mobilization. The time before normal strength is regained after the remodeling phase is not known.

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Asghar, Muhammad, Nadeem Iqbal, Sadia Sagar Iqbal, Mohsin Farooq, and Tahir Jamil. "Ablation and thermo-mechanical tailoring of EPDM rubber using carbon fibers." Journal of Polymer Engineering 36, no. 7 (September 1, 2016): 713–22. http://dx.doi.org/10.1515/polyeng-2015-0337.

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Abstract Carbon fibers (CFs) are incorporated into ethylene propylene diene monomer (EPDM) rubber to fabricate charring elastomeric ablative composites for ultrahigh temperature applications. Ablation characteristics of the ablative composites were evaluated using ASTM E285-08. Variant content incorporation of short CFs in the basic composite formulation reduced the backface temperature acclivity and the ablation rate rose up to 48% and 78%, correspondingly. Thermal stability and endothermic capability were improved with increasing short fiber contents in the rubber matrix. Experimental thermal conductivity measurement results elucidate that thermal conductivity reduces 60% at 473 K with 6 wt% addition of the fibers. A remarkable improvement was scrutinized in the tensile strength and rubber hardness with increasing fiber to matrix ratio. Scanning electron microscopy (SEM)/energy dispersive X-ray spectroscopy (EDS) analysis of the composite specimens revealed the uniform dispersion of CFs within the host matrix, formation of voids during ablation, char-reinforcement interaction and composition of the charred ablators and the impregnated fibers.

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Xu, Yi Hua, Chun Bo Hu, Zhuo Xiong Zeng, and Yu Xin Yang. "Research on Mechanical Model of EPDM Insulation Charring Layer." Applied Mechanics and Materials 152-154 (January 2012): 57–63. http://dx.doi.org/10.4028/www.scientific.net/amm.152-154.57.

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The coupling effect of physics, chemistry and mechanics is through charring layer in the process of ablation of the insulation material. Description of the structure and mechanical properties of charring layer is the critical factor to numerical computation for foretelling the ablation of insulation material. The characteristic of charring layer structure of EPDM insulation at sorts of ablating condition were analyzed, and based on characteristic of porous medium of charring layer, the mechanical model with porosity as parameter was modeled by using theory of solid porous medium. According to the intensity determination of charring layer, the coefficient of intensity model was determined, then, the failure criterion of charring layer was set up, which can provide the mechanical parameters of charring layer for numerical computation to foretell the ablation of insulation material.

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McDermott, Ryan M., Jitendra S. Tate, and Joseph H. Koo. "Exploration of a new affordable thermal protection system utilizing 2.5D silica/polysiloxane composite." Journal of Composite Materials 56, no. 5 (December 22, 2021): 685–98. http://dx.doi.org/10.1177/00219983211038622.

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Ablative materials are used as thermal protection systems (TPS) for reentry vehicles and solid rocket motor (SRM) nozzle applications. Phenolic and cyanate ester are the state-of-the-art (SOTA) resin systems used in many of the ablative composites today, including MX-2600 (silica/phenolic) from Cytec Solvay Group. While these ablatives have worked well, more demanding requirements drive the need for affordable lightweight advanced composites capable of handling high heat fluxes with minimal mass loss. These advanced ablative composites result in lighter reentry heat shields and solid rocket motors, increasing payload capabilities of spacecraft and rockets. Molding compound made of aerospace grade 99% SiO2 fabric and polysiloxane resin showed considerable improvement over MX-2600 in ablation properties in recent studies. In order to meet increased mechanical strength demands, NASA recently developed an ablative composite using a 3D quartz woven/cyanate ester composite material designed for the Orion spacecraft. While 3D woven composites provide excellent out-of-plane mechanical and ablation properties, they are very expensive, which limits their application. This research explores needle-punched silica fabric, sometimes referred to as 2.5D, which provides similar out-of-plane mechanical benefits to 3D woven composites in a more flexible VARTM manufacturing process at a much lower cost. The needle-punched silica fabric was infiltrated with polysiloxane resin and mechanical tests were performed. The needle-punched composites showed an increase of 181% in flexural strength, 27% in interlaminar shear strength, 2% in tensile strength, and 13% in compressive strength. In aerothermal ablation tests, the 2.5D out-performed the 2D laminate in char yield, mass loss, and recession rate; and in char yield and mass loss (%), the 2.5D out-performed the industry standard MX-2600 molding compound. The increased out-of-plane strength and char yield make it a promising and affordable ablative candidate for ablation performance with enhanced mechanical properties.

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Mancia, Lauren, Eli Vlaisavljevich, Nyousha Yousefi, Adam Maxwell, Geoffrey W. Siegel, Zhen Xu, and Eric Johnsen. "Focused ultrasound ablation of solid tumors: Feasibility of planning tissue-selective treatments." Journal of Clinical Oncology 38, no. 15_suppl (May 20, 2020): e15600-e15600. http://dx.doi.org/10.1200/jco.2020.38.15_suppl.e15600.

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e15600 Background: Focused ultrasound (FUS) is a noninvasive, nonionizing, repeatable local ablative therapy that induces mechanical fractionation or thermal necrosis of a variety of solid tumors including hepatocellular carcinoma, prostate cancer, and desmoid fibromatosis. Recent feasibility studies in animal models have demonstrated the possibility of designing focused ultrasound treatments that are selective (e.g. spare healthy tissue, nerves, and blood vessels) due to differences in tissue and tumor mechanical properties. Given wide variation in individual tumor and patient characteristics, mechanics-based predictions of ablation zone features in different tissues under a range of FUS device settings are needed to permit personalized treatment planning. Methods: A finite difference computational method is used to simulate FUS ablation of tissues with variable mechanical properties (shear moduli of 0.6 – 200 kPa) under different FUS sonication parameters (frequency and peak pressure). The model calculates strain fields contributing to tissue ablation in FUS treatments which are used to predict ablation zone radii and boundary characteristics. Simulation predictions in model tissues are then compared to histology obtained from FUS-treated porcine tissue samples with similar mechanical properties. Results: The mechanical properties of model tissues and FUS treatment parameters have distinct effects on predicted minimum ablation zone radii. For example, smaller ablation zone radii are achieved in stiffer vessel wall than liver under given FUS sonication parameters. In each tissue, lower frequency and higher peak pressure FUS sonication predict a larger ablation zone. Combined variation of sonication frequency and peak pressure are found to achieve wider variation in ablation zone radius than previously achieved with frequency variation alone. Predicted ablation zone radii and boundary characteristics are consistent with the observed histology of FUS-treated tissues. Conclusions: Results show that simulations accounting for tissue mechanical properties and device settings can predict tissue selectivity and ablation zone characteristics observed in FUS procedures. This study demonstrates the potential of using noninvasive measurements of tissue and tumor properties obtained, for example, via shear wave elastography, in combination with micromechanical tissue ablation simulations to develop personalized, selective focused ultrasound treatments for solid tumors.

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Wang, Wentao, Lisheng Zhou, Yang Li, Peng Li, Guohui Chen, and Shishan Yang. "Study on the Ablation Properties of Nano-graphite Modified EPDM Insulators." Journal of Physics: Conference Series 2133, no. 1 (November 1, 2021): 012019. http://dx.doi.org/10.1088/1742-6596/2133/1/012019.

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Abstract To improve the anti-ablative property of EPDM-based composites, nano-graphite powder as anti-ablation filler was introduced to optimize the EPDM insulation material formulas. Characterization of anti-ablation performance showed that the composite at the nano-graphite content of 10phr exhibited the best anti-ablation and mechanical performances, such as: a linear ablation rate of 0.062 mm/s, a mass ablation rate of 0.048 g/s, tensile strength of 5.69 MPa and Elongation at break of 391.2%. The nano-graphite was proven to be an effective material which is beneficial to improve the anti-ablation of the EPDM composites.

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Fite, Brett Z., James Wang, Pejman Ghanouni, and Katherine W. Ferrara. "A Review of Imaging Methods to Assess Ultrasound-Mediated Ablation." BME Frontiers 2022 (May 2, 2022): 1–17. http://dx.doi.org/10.34133/2022/9758652.

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Ultrasound ablation techniques are minimally invasive alternatives to surgical resection and have rapidly increased in use. The response of tissue to HIFU ablation differs based on the relative contributions of thermal and mechanical effects, which can be varied to achieve optimal ablation parameters for a given tissue type and location. In tumor ablation, similar to surgical resection, it is desirable to include a safety margin of ablated tissue around the entirety of the tumor. A factor in optimizing ablative techniques is minimizing the recurrence rate, which can be due to incomplete ablation of the target tissue. Further, combining focal ablation with immunotherapy is likely to be key for effective treatment of metastatic cancer, and therefore characterizing the impact of ablation on the tumor microenvironment will be important. Thus, visualization and quantification of the extent of ablation is an integral component of ablative procedures. The aim of this review article is to describe the radiological findings after ultrasound ablation across multiple imaging modalities. This review presents readers with a general overview of the current and emerging imaging methods to assess the efficacy of ultrasound ablative treatments.

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Yin, Jian, Hong Bo Zhang, Xiang Xiong, and Hui Jin Tao. "Ablation Behaviors of 3D Fine Woven Pierced Carbon/Carbon Composites." Advanced Materials Research 1033-1034 (October 2014): 864–68. http://dx.doi.org/10.4028/www.scientific.net/amr.1033-1034.864.

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The ablation behaviors of 3D fine woven pierced carbon/carbon (C/C) composites were tested on an arc heater and their ablation morphologies were observed by scanning electron microscopy (SEM). It shows that ablation of 3D fine woven pierced C/C composites tends to start at interfaces, defects and pores. Cracks mainly yield at the boundaries of carbon fiber bundles, interfaces of carbon fiber felts during the ablating processes. The ablation properties of 3D C/C composites in parallel direction are better than that in vertical direction. In addition, the work indicates that the ablation process is mainly controlled by mechanical denudation.

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Li, Dong, Hong Xia Chen, Zhu Chen, Yang Li, Shu Xin Wu, and Ji Gui Wang. "Mechanical and Ablative Properties of Polyacrylonitrile(PAN)/RTV Silicone Internal Insulating Composites." Advanced Materials Research 399-401 (November 2011): 403–6. http://dx.doi.org/10.4028/www.scientific.net/amr.399-401.403.

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The polyacrylonitrile short fibers/ room temperature vulcanizing silicone rubber (PAN/RTV silicone) composites were prepared by mechanical mixing method and vulcanization at room temperature for 7 days as internal insulator. The effects of the content of fiber on the mechanical and ablative performances for the composites were investigated. The results show that with increasing content of PAN fiber filled, the tensile strength increases, the break elongation decreases, and the ablation rate(Rt) of PAN/silicone composites decreases rapidly at first, then increases. When PAN fiber content is 10phr, the ablation rate(Rt) is 0.06mm/s.

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Kuttiwong, Keeratikarn, and Jantrawan Pumchusak. "Improvement of Thermal and Ablative Properties of Phenolic Resin by SiC and MMT." Key Engineering Materials 707 (September 2016): 8–12. http://dx.doi.org/10.4028/www.scientific.net/kem.707.8.

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In this work, the improvement of thermal and ablative properties of the phenolic resin by the addition of silicon carbide (SiC) and montmorillonite (MMT) were studied. The phenolic composites were fabricated by hot compression. The thermal stabilities, mechanical properties and ablative properties of the neat phenolic resin and the SiC/MMT phenolic composites were examined using a Lloyd universal testing machine, thermogravimetric analysis (TGA) and ablation tests (an oxyacetylene torch), respectively. Mass ablation rates were measured after flame exposure. The results showed that SiC/MMT provided the higher thermal stabilities and lower ablation rates to the phenolic resin.

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Ma, Li, Lu Jv He, Cai Song Mo, Li Bin Zhang, Mao Sen Pan, and Yang F. feng Huang. "Ablation Behaviour and Microstructure of Carbon/Carbon and Hybrid Carbon/Carbon Composites Based on Plasma Torch Heating." Advanced Composites Letters 26, no. 4 (July 2017): 096369351702600. http://dx.doi.org/10.1177/096369351702600401.

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The ablation properties and morphologies of two kinds of fine Fine-woven pierced composites materials, carbon/carbon (C/C) and hybrid C/C with tungsten (W) filaments in z directional carbon fibre bundles, were investigated. A plasma torch was used to explore the ablative characteristics in terms of linear/bulk ablation rate and microscopic pattern of ablation. Surface and in-depth temperatures during ablation were measured by using optical pyrometers and thermocouples. The experimental results showed that the C/C composite presented the best ablation resistance performance, followed by the hybrid C/C composite, while that of graphite was the worst. It was found that the thermo-mechanical ablation resistance of carbon matrix is equal to that of carbon fibres. The existence of WC not only had a faster intrinsic ablation velocity, but also accelerated the ablation velocity of the carbon fibres and carbon matrix, and significantly improved the ablation velocity of the carbon fibres.

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Landry, Thomas G., Jessica Gannon, Eli Vlaisavljevich, Matthew G. Mallay, Jeffrey K. Woodacre, Sidney Croul, James P. Fawcett, and Jeremy A. Brown. "Endoscopic Coregistered Ultrasound Imaging and Precision Histotripsy: Initial In Vivo Evaluation." BME Frontiers 2022 (July 11, 2022): 1–14. http://dx.doi.org/10.34133/2022/9794321.

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Objective. Initial performance evaluation of a system for simultaneous high-resolution ultrasound imaging and focused mechanical submillimeter histotripsy ablation in rat brains. Impact Statement. This study used a novel combination of high-resolution imaging and histotripsy in an endoscopic form. This would provide neurosurgeons with unprecedented accuracy in targeting and executing nonthermal ablations in minimally invasive surgeries. Introduction. Histotripsy is a safe and effective nonthermal focused ablation technique. However, neurosurgical applications, such as brain tumor ablation, are difficult due to the presence of the skull. Current devices are too large to use in the minimally invasive approaches surgeons prefer. We have developed a combined imaging and histotripsy endoscope to provide neurosurgeons with a new tool for this application. Methods. The histotripsy component had a 10 mm diameter, operating at 6.3 MHz. Affixed within a cutout hole in its center was a 30 MHz ultrasound imaging array. This coregistered pair was used to ablate brain tissue of anesthetized rats while imaging. Histological sections were examined, and qualitative descriptions of ablations and basic shape descriptive statistics were generated. Results. Complete ablations with submillimeter area were produced in seconds, including with a moving device. Ablation progress could be monitored in real time using power Doppler imaging, and B-mode was effective for monitoring post-ablation bleeding. Collateral damage was minimal, with a 100 μm maximum distance of cellular damage from the ablation margin. Conclusion. The results demonstrate a promising hardware suite to enable precision ablations in endoscopic procedures or fundamental preclinical research in histotripsy, neuroscience, and cancer.

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Chen, Zhu, Dong Li, Ai Juan Shi, Yang Li, and Shu Xin Wu. "Properties Characteristics of Silicone Inhibitors." Advanced Materials Research 750-752 (August 2013): 43–46. http://dx.doi.org/10.4028/www.scientific.net/amr.750-752.43.

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The short carbon fibers/ room temperature vulcanizing silicone rubber composites were prepared by mechanical mixing method and vulcanization at room temperature for 7 days as internal insulator. The effects of the content of fiber on the mechanical , ablative and adhesive performances for the composites were investigated. The results show that with increasing content of carbon fiber filled, the tensile strength increases, the break elongation decreases, and the ablation rate (Rt) of the composites decreases rapidly at first, then increases. When carbon fiber content is 10phr, the ablation rate (Rt) is 0.076mm/s. no significant differences in adhesive values were obtained yet.

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Han, Qiuchen, Lei Chang, Zhaoqun Sun, Jiaqi Sun, Zengyan Wei, Pingping Wang, Ziyang Xiu, Huasong Gou, Pengchao Kang, and Gaohui Wu. "Ablation Mechanism of AlSiB-C/C Composites under an Oxy-Acetylene Torch." Metals 13, no. 1 (January 12, 2023): 160. http://dx.doi.org/10.3390/met13010160.

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In order to improve the ablation resistance of C/C composites, an AlSiB alloy (mass ratio of Al/Si/B = 2:4:1) was used as a dissipative agent to fill the pores of a C/C composites matrix by reactive melt infiltration to prepare AlSiB-C/C composites. The microstructure evolution and ablation behavior of the obtained AlSiB-C/C composites (mass ratio of Al/Si/B = 2:4:1) under oxy-acetylene flame were investigated by SEM after ablating for 25 s, 50 s, 100 s and 150 s. At the beginning of the ablation process, thermal chemical erosion played a leading part. By using the heat-absorption effect of sweating and the sealing protection effect of the oxide layer, AlSiB-C/C composites significantly reduced the ablation surface temperature, and the linear ablation rate was 4.04 μm/s. With the process of ablation, thermal mechanical erosion tended to dominate. The specimen surface could not form a continuous covering of oxide film to slow down the flame scour, resulting in non-uniform ablation and further expansion of the ablation pit. The self-transpiration cooling behavior and the self-sealing of the ablation products of the dissipative agent played an important role in reducing the extent of thermal chemical erosion and preventing matrix ablation.

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Zuo, Hongmei, Fangtao Ruan, Hongjie Wang, He Wang, Xu Wang, Yufan Huang, Rui Wang, Lihua Zou, Zhenzhen Xu, and Diansen Li. "Advances in Ablation or Oxidation Mechanisms and Behaviors of Carbon Fiber-Reinforced Si-Based Composites." Molecules 28, no. 16 (August 11, 2023): 6022. http://dx.doi.org/10.3390/molecules28166022.

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Composites with excellent thermomechanical and thermochemical properties are urgently needed in the aerospace field, especially for structural applications under high-temperature conditions. Carbon fiber-reinforced Si-based composites are considered the most promising potential high-temperature materials due to their excellent oxidation resistance and ablative behaviors, good structural designability, and excellent mechanical properties. The reinforcement of the relevant composites mainly involves carbon fiber, which possesses good mechanical and temperature resistance abilities. In this paper, the ablation behaviors and mechanisms of related composites are reviewed. For carbon fiber-reinforced pure Si-based composites (C/SiM composites), the anti-ablation mechanism is mainly attributed to the continuous glassy SiO2, which inhibits the damage of the substrate. For C/SiM composite doping with refractory metal compounds, the oxides of Si and refractory metal together protect the main substrate from ablation and oxidation. Moreover, in addition to thermochemical damage, thermophysical and thermomechanical behavior severely destroy the surface coating of the substrate.

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Deng, Yi, Payam S. Naeini, Mehdi Razavi, Charles D. Collard, Daniel A. Tolpin, and James M. Anton. "Anesthetic Management in Radiofrequency Catheter Ablation of Ventricular Tachycardia." Texas Heart Institute Journal 43, no. 6 (December 1, 2016): 496–502. http://dx.doi.org/10.14503/thij-15-5688.

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Radiofrequency catheter ablation is increasingly being used to treat patients who have ventricular tachycardia, and anesthesiologists frequently manage their perioperative care. This narrative review is intended to familiarize anesthesiologists with preprocedural, intraprocedural, and postprocedural implications of this ablation. Ventricular tachycardia typically arises from structural heart disease, most often from scar tissue after myocardial infarction. Many patients thus affected will benefit from radiofrequency catheter ablation in the electrophysiology laboratory to ablate the foci of arrhythmogenesis. The pathophysiology of ventricular tachycardia is complex, as are the technical aspects of mapping and ablating these arrhythmias. Patients often have substantial comorbidities and tenuous hemodynamic status, necessitating pharmacologic and mechanical cardiopulmonary support. General anesthesia and monitored anesthesia care, when used for sedation during ablation, can lead to drug interactions and side effects in the presence of ventricular tachycardia, so anesthesiologists should also be aware of potential perioperative complications. We discuss variables that can help anesthesiologists safely guide patients through the challenges of radiofrequency catheter ablation of ventricular tachycardia.

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Qu, Hongjian, Le Wang, Kun Hui, Cheng Bian, Hongyan Li, Yiwen Guan, Tao Luan, and Ning Yan. "Enhancing Thermal Insulation of EPDM Ablators via Constructing Alternating Planar Architectures." Polymers 14, no. 8 (April 12, 2022): 1570. http://dx.doi.org/10.3390/polym14081570.

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Ethylene–propylene–diene monomer (EPDM) composites were usually enhanced with ablative additives to protect solid rocket motor (SRMs) casings. However, the poor thermal insulation caused by the high thermal conductive ablative fillers can lead to rocket motor failure. Herein, the novel EPDM composites containing alternating layers of ablative EPDM (AM) and heat-insulated EPDM (HM) were prepared through layer-multiplying extrusion. Compared with conventional EPDM ablative material, the multilayer composites showed enhanced thermal insulation and mechanical properties that could be further improved by tuning the number of layers. The ablation and thermal insulation properties possessing in AM and HM layers could be combined by forced assembly during co-extrusion, and the alternating multilayer composite was capable of showing the effect of each component. In particular, compared with AM, the maximum back-face temperature with 40 alternating layers of AM/HM decreased from 96.2 °C to 75.6 °C during oxyacetylene test, while the good ablation properties were preserved in the AM component. This significant improvement was attributed to the planar orientation and densification of ablative additives, and the interruption of conductive pathways in the through-plane direction of AM/HM alternating laminate. The anisotropic EPDM composites featuring mechanical robustness, good ablative resistance and thermal insulation suggest considerable potential application in the aerospace industry.

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CLARISSE, J. M., C. BOUDESOCQUE-DUBOIS, and S. GAUTHIER. "Linear perturbation response of self-similar ablative flows relevant to inertial confinement fusion." Journal of Fluid Mechanics 609 (July 31, 2008): 1–48. http://dx.doi.org/10.1017/s0022112008002279.

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A family of exact similarity solutions for inviscid compressible ablative flows in slab symmetry with nonlinear heat conduction is proposed for studying unsteadiness and compressibility effects on the hydrodynamic stability of ablation fronts relevant to inertial confinement fusion. Dynamical multi-domain Chebyshev spectral methods are employed for computing both the similarity solution and its time-dependent linear perturbations. This approach has been exploited to analyse the linear stability properties of two self-similar ablative configurations subjected to direct laser illumination asymmetries. Linear perturbation temporal and reduced responses are analysed, evidencing a maximum instability for illumination asymmetries of zero transverse wavenumber as well as three distinct regimes of ablation-front distortion evolution, and emphasizing the importance of the mean flow unsteadiness, compressibility and stratification.

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Seydoux-Guillaume, Anne-Magali, Rémi Freydier, Franck Poitrasson, François-Xavier D 'Abzac, Richard Wirth, and Lucien Datas. "Dominance of mechanical over thermally induced damage during femtosecond laser ablation of monazite." European Journal of Mineralogy 22, no. 2 (April 13, 2010): 235–44. http://dx.doi.org/10.1127/0935-1221/2010/0022-2001.

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Gorskiy, V. V., M. G. Kovalsky, and V. G. Resh. "Method of Calculating Carbon Ablation in the Jet of Liquid Rocket Engine Combustion Products." Herald of the Bauman Moscow State Technical University. Series Mechanical Engineering, no. 5 (128) (October 2019): 4–21. http://dx.doi.org/10.18698/0236-3941-2019-5-4-21.

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Nowadays carbon materials are widely used as ablating thermal protection for high-temperature structural elements in aerospace technology. Prediction of changes in the shape of the external surfaces of these elements, due to the burning of thermal protection, is closely related to the use of computational-theoretical methods describing the flow of various physicochemical and mechanical processes associated with the occurrence of the phenomenon under consideration. At the same time, it is crucial to test such methods on the results of experimental studies conducted under conditions which are implemented during the process of testing thermal protection in jets of aerodynamic units. The main elements of ablation of carbon materials include their erosion, i.e., mechanical ablation of mass, observed in high-pressure gas flows. In the process of experimental development, it is necessary to carry out research on large-scale models, which has led to widespread use of underexpanded jets of combustion products of liquid rocket engine combustion products for modeling the erosion process of thermal protection. The theoretical model of ablation of thermal protection in such jets requires taking into account the complex chemical composition of the gas mixture flowing into the model; physical and chemical interaction of this gas with thermal protection, which causes gasification of the latter; use of mathematical models describing the process of material erosion due to mechanical impact of high-pressure gas flow. The paper describes the development of the carbon material ablation calculating and theoretical methodology which could be used to determine the material erosion characteristics on the basis of solving a complex problem of circumfluence, heating, heat penetration and ablation of thermal protection.

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Indalécio Pachón Mateos, Enrique, José Carlos Pachón Mateos Mateos, Ricardo Carneiro Amarante, Carlos Thiene Cunha Pachón, Tasso Júlio Lobo, Tomás Guillermo Santillana Peña, Juán Carlos Zerpa Acosta, Juán Carlos Pachón Mateos, Felipe Ortêncio, and Christian Higuti. "Prevention of Esophageal Damage During Ablation of Atrial Fibrillation by the Esophagus Mechanical Deviation." Journal of Cardiac Arrhythmias 32, no. 4 (April 16, 2020): 278–90. http://dx.doi.org/10.24207/jca.v32n4.982_in.

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Atrial fibrillation is the most prevalent arrhythmia in the world population. Despite the use of antiarrhythmics, it is difficult to control clinically, causing symptoms and mainly generating risk of a thromboembolic event. Since 1998, by means of radiofrequency ablation, the treatment of atrial fibrillation has completely changed, but together with this important evolution complications from this ablative treatment technique have also started. In addition to the pulmonary vein stenosis caused by the ablation and later corrected with the change in the technique, atrioesophageal fistulas appeared due to the application of radiofrequency in the posterior wall of the left atrium. This wall is very close (0.5 cm onaverage) to the esophagus, which facilitates the formation of the fistula that leads to the death of almost 100% of the affected patients, despite the various treatment measurements already developed. To avoid this serious complication, several authors have created techniques to protect the esophagus including its mechanical deviation to a region opposite to the radiofrequency application, taking advantage of its mobility and easiness of handling. The mechanical deviation of the esophagus has proven to be the simplest, cheapest and most efficient way to protect this organ from radiofrequency thermal damage during atrial fibrillation ablation.

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Liu, Yanhui, Jingyu Su, Zhengshuai Yin, Yong Li, Ye Zhi, and Jinglong Gao. "Ablation and mechanical investigation of heat vulcanizing silicone rubber (HVSR) composite containing carbon fibers." Journal of Polymer Engineering 37, no. 5 (May 24, 2017): 521–28. http://dx.doi.org/10.1515/polyeng-2016-0130.

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Abstract In this study, heat vulcanizing silicone rubber (HVSR) composites were prepared and the impact of the addition of carbon fibers (CFs) on the mechanical and ablation properties of the composite was demonstrated. It was found that with increasing content of CFs, the tensile property and the hardness of the composite increased significantly. The back-face temperature, the ablation rate and the ablation mechanism of the composite were discussed based on the data derived from several characterization methods, including oxygen-acetylene ablation device, scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR). Along with the increasing of the content of CFs, the mass and linear ablation rates both decreased, but the back-face temperature increased. The interaction between ablation layer and the composite became intense due to the addition of the CFs, which led to the difficult peel-off of the ablation layer. Four layers can be formed after the oxygen-acetylene ablation of the composite including the surface layer, the carbonization layer, the pyrolysis layer and the matrix layer. The ablation mechanism was also proposed. It mainly involves the carbonization of the composite, the ceramization of SiC and the shielding effect of the ablated layer.

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Zweig, A. D. "A thermo‐mechanical model for laser ablation." Journal of Applied Physics 70, no. 3 (August 1991): 1684–91. http://dx.doi.org/10.1063/1.349537.

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Martignani, C., I. Diemberger, M. Biffi, C. Valzania, M. Bertini, G. Domenichini, and G. Boriani. "Atrial fibrillation ablation: beyond electro-mechanical matters." European Heart Journal 29, no. 22 (May 30, 2008): 2818–19. http://dx.doi.org/10.1093/eurheartj/ehn403.

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Frankel, David S. "Mechanical Esophageal Deviation During Atrial Fibrillation Ablation." JACC: Clinical Electrophysiology 4, no. 8 (August 2018): 1031–32. http://dx.doi.org/10.1016/j.jacep.2018.05.001.

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Hibst, Raimund. "Mechanical effects of erbium:YAG laser bone ablation." Lasers in Surgery and Medicine 12, no. 2 (1992): 125–30. http://dx.doi.org/10.1002/lsm.1900120203.

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Vu Van, Ba, Linh Ngo Thi Hai, Kien Trung Hoang, Nghiem Khanh Xuan, Thinh Duc Do, Hung Manh Nguyen, Nguyen Tran Thuy, and Dung Tien Le. "Radiofrequency catheter ablation of newly diagnosed paroxysmal atrial fibrillation in a patient with mitral and aortic mechanical valves: A case study." Tạp chí Phẫu thuật Tim mạch và Lồng ngực Việt Nam 38 (July 28, 2022): 5–11. http://dx.doi.org/10.47972/vjcts.v38i.775.

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Background: Radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) in patients with prosthetic valve is still a challenge because of the higher recurrence rate and difficult manipulation of catheters in the left atrium which may lead to higher risk of complications. We presented the first AF ablation in Vietnam of a patient who had mitral and aortic mechanical valves. Case summary: A 54-year-old man who had two mechanical heart valves (mitral and aortic) implanted 16 years ago was newly diagnosed with symptomatic paroxysmal AF for the past 4 months at a province general hospital. The patient was treated with amiodarone but still symptomatic and could not tolerate the medication. A referral to our centre was made for consideration of radiofrequency catheter ablation. Sinus rhythm was successfully restored after pulmonary vein isolation, cavo-tricuspid isthmus ablation, and tailor-ablation. At the last follow-up at 9-months post-ablation, the patient was still in sinus rhythm and asymptomatic. Discussion: Catheter ablation of AF in patients with mechanical heart valve(s) is challenging due to increased difficulty in accessing the left atrium as well as catheter manipulation and ablation inside the atrium. Nevertheless, this procedure could be safely performed in high experience centres.

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Zhang, Xue Mei, Song Li, Long Fei Gao, Kun Yu, Yuan Yu Xiao, Ke Xin Dong, and Qiu Mian Lu. "Research on the Performance of Carbon Fiber Reinforced Inorganic Polymer Composite." Solid State Phenomena 281 (August 2018): 272–77. http://dx.doi.org/10.4028/www.scientific.net/ssp.281.272.

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This paper introduced a novel carbon fiber reinforced inorganic polymer non-sintering ceramic composite. It is composed of a low temperature curing material system, and can be manufactured by a traditional process for resin matrix composites. According to relevant test standards, the performances including the mechanical properties, the coefficient of linear expansion and the ablation ration were studied. The results show that the tensile strength is more than 150MPa, the bending strength is more than120MPa, the average coefficient of linear expansion is less than 0.213×10-6/°C(between room temperature and 800°C), the ablation ratio is less than 0.0715mm/s, the mass retention ratio after ablation at 1000°C for 600s is less than98%. The composite could be used for the micro ablative in large area thermal protection such as national defense, aircraft and so on.

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Iqbal, Sadia Sagar, Nadeem Iqbal, Tahir Jamil, and Arshad Bashir. "Exfoliated Sodium Montmorillonite Reinforced Elastomeric Nanocomposites: Ablation, Thermal Transport/Decomposition/Transitions and Mechanical Aspects)." International Journal of Materials, Mechanics and Manufacturing 6, no. 1 (February 2018): 19–25. http://dx.doi.org/10.18178/ijmmm.2018.6.1.340.

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Singh, Sundeep, and Roderick Melnik. "Fluid–Structure Interaction and Non-Fourier Effects in Coupled Electro-Thermo-Mechanical Models for Cardiac Ablation." Fluids 6, no. 8 (August 20, 2021): 294. http://dx.doi.org/10.3390/fluids6080294.

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In this study, a fully coupled electro-thermo-mechanical model of radiofrequency (RF)-assisted cardiac ablation has been developed, incorporating fluid–structure interaction, thermal relaxation time effects and porous media approach. A non-Fourier based bio-heat transfer model has been used for predicting the temperature distribution and ablation zone during the cardiac ablation. The blood has been modeled as a Newtonian fluid and the velocity fields are obtained utilizing the Navier–Stokes equations. The thermal stresses induced due to the heating of the cardiac tissue have also been accounted. Parametric studies have been conducted to investigate the effect of cardiac tissue porosity, thermal relaxation time effects, electrode insertion depths and orientations on the treatment outcomes of the cardiac ablation. The results are presented in terms of predicted temperature distributions and ablation volumes for different cases of interest utilizing a finite element based COMSOL Multiphysics software. It has been found that electrode insertion depth and orientation has a significant effect on the treatment outcomes of cardiac ablation. Further, porosity of cardiac tissue also plays an important role in the prediction of temperature distribution and ablation volume during RF-assisted cardiac ablation. Moreover, thermal relaxation times only affect the treatment outcomes for shorter treatment times of less than 30 s.

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Kandarian, S. C., and T. P. White. "Mechanical deficit persists during long-term muscle hypertrophy." Journal of Applied Physiology 69, no. 3 (September 1, 1990): 861–67. http://dx.doi.org/10.1152/jappl.1990.69.3.861.

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Hypotheses were tested that the deficit in maximum isometric force normalized to muscle cross-sectional area (i.e., specific Po, N/cm2) of hypertrophied muscle would return to control value with time and that the rate and magnitude of adaptation of specific force would not differ between soleus and plantaris muscles. Ablation operations of the gastrocnemius and plantaris muscles or the gastrocnemius and soleus muscles were done to induce hypertrophy of synergistic muscle left intact in female Wistar rats (n = 47) at 5 wk of age. The hypertrophied soleus and plantaris muscles and control muscles from other age-matched rats (n = 22) were studied from days 30 to 240 thereafter. Po was measured in vitro at 25 degrees C in oxygenated Krebs-Ringer bicarbonate. Compared with control values, soleus muscle cross-sectional area increased 41-15% from days 30 to 240 after ablation, whereas Po increased 11 and 15% only at days 60 and 90. Compared with control values, plantaris muscle cross-sectional area increased 52% at day 30, 40% from days 60 through 120, and 15% at day 240. Plantaris muscle Po increased 25% from days 30 to 120 but at day 240 was not different from control value. Changes in muscle architecture were negligible after ablation in both muscles. Specific Po was depressed from 11 to 28% for both muscles at all times. At no time after the ablation of synergistic muscle did the increased muscle cross-sectional area contribute fully to isometric force production.

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Zhou, Weiguo, Keyu Gong, Jie Wan, Lulu Quan, Yuchuan Chu, and Yong Cao. "Molecular dynamics simulation study on ablation of silicon by water-jet-guided laser." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 231, no. 6 (August 8, 2016): 1217–25. http://dx.doi.org/10.1177/0954408916662088.

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Stillinger–Weber potential and Z-layer energy model were adopted in molecular dynamics simulation to study the ablation of silicon by water-jet-guided femtosecond laser, and comparison was made by ablating silicon with or without water-jet cooling in our simulations. Simulation results indicated that with water-jet cooling, the thermal-affected zone could be reduced in area, and the peak of density could disappear more quickly. It was therefore concluded that water-jet-guided laser could be used to considerably improve the ablation quality of silicon.

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Ortiz, Rocío, Pooja Basnett, Ipsita Roy, and Iban Quintana. "Picosecond Laser Ablation of Polyhydroxyalkanoates (PHAs): Comparative Study of Neat and Blended Material Response." Polymers 12, no. 1 (January 5, 2020): 127. http://dx.doi.org/10.3390/polym12010127.

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Polyhydroxyalkanoates (PHAs) have emerged as a promising biodegradable and biocompatible material for scaffold manufacturing in the tissue engineering field and food packaging. Surface modification is usually required to improve cell biocompatibility and/or reduce bacteria proliferation. Picosecond laser ablation was applied for surface micro structuring of short- and medium-chain length-PHAs and its blend. The response of each material as a function of laser energy and wavelength was analyzed. Picosecond pulsed laser modified the surface topography without affecting the material properties. UV wavelength irradiation showed halved ablation thresholds compared to visible (VIS) wavelength, revealing a greater photochemical nature of the ablation process at ultraviolet (UV) wavelength. Nevertheless, the ablation rate and, therefore, ablation efficiency did not show a clear dependence on beam wavelength. The different mechanical behavior of the considered PHAs did not lead to different ablation thresholds on each polymer at a constant wavelength, suggesting the interplay of the material mechanical parameters to equalize ablation thresholds. Blended-PHA showed a significant reduction in the ablation threshold under VIS irradiation respect to the neat PHAs. Picosecond ablation was proved to be a convenient technique for micro structuring of PHAs to generate surface microfeatures appropriate to influence cell behavior and improve the biocompatibility of scaffolds in tissue engineering.

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Du, Qin Jun, Chuan Dai Dong, and Lian Liang Ba. "Mechanical Design of a Needle Driven Robot." Advanced Materials Research 121-122 (June 2010): 905–10. http://dx.doi.org/10.4028/www.scientific.net/amr.121-122.905.

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This paper describes mechanical design for a minimally invasive surgery robot, the robot will help surgons to realize high quality and precise localization in radio frequency ablation for patients with liver tumors. At present, radio frequency ablation minimally invasive more and more using in the minimally surgery operation, therefore, to develope a medical robot assisting surgons to achieve success in the radio frequency operation is necessary. In this paper, we analysis the radio frequency operation, according to the requirement of the minimally invasive operation, a medical robot structure is designed. We discuss the robot work space, gearbox mechanical and robot arm design. through localization experiment shows that the robot precise meet the minimally invasive operation requirements.

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Santangeli, Pasquale, Luigi DI Biase, Rong Bai, Rodney Horton, J. David Burkhardt, Javier Sanchez, Justin Price, and Andrea Natale. "Advances in Catheter Ablation: Atrial Fibrillation Ablation in Patients With Mitral Mechanical Prosthetic Valve." Current Cardiology Reviews 8, no. 4 (October 24, 2012): 362–67. http://dx.doi.org/10.2174/157340312803760767.

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Palaninathan, R., and S. Bindu. "Modeling of Mechanical Ablation in Thermal Protection Systems." Journal of Spacecraft and Rockets 42, no. 6 (November 2005): 971–79. http://dx.doi.org/10.2514/1.10710.

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HERWEG, BENGT, NANCY JOHNSON, GILBERT POSTLER, ANNE B. CURTIS, S. SERGE BAROLD, and ARZU ILERCIL. "Mechanical Esophageal Deflection During Ablation of Atrial Fibrillation." Pacing and Clinical Electrophysiology 29, no. 9 (September 2006): 957–61. http://dx.doi.org/10.1111/j.1540-8159.2006.00470.x.

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Sacher, F., R. Weerasooriya, and P. Jais. "Atrial fibrillation ablation: beyond electro-mechanical matters: reply." European Heart Journal 29, no. 22 (May 30, 2008): 2819. http://dx.doi.org/10.1093/eurheartj/ehn404.

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Altamirano, Jaime, Robin Wachsner, and Donna Gallik. "Mechanical Ablation of Concealed Left Lateral Bypass Tract." Journal of Cardiovascular Pharmacology and Therapeutics 2, no. 3 (September 1997): 223–27. http://dx.doi.org/10.1177/107424849700200309.

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Elias, S. "Mechanical-Chemical Endovenous Ablation: A New Tumescentless Technique." Journal of Vascular Surgery 50, no. 4 (October 2009): 968. http://dx.doi.org/10.1016/j.jvs.2009.07.036.

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KITAI, M. S., and V. A. SEMCHISHEN. "LASER ABLATION OF POLYMERS, CAUSED BY MECHANICAL STRESSES." Le Journal de Physique IV 01, no. C7 (December 1991): C7–133—C7–133. http://dx.doi.org/10.1051/jp4:1991729.

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Adler, Adam C., and Ramesh Kodavatiganti. "Mechanical Support With Impella During Malignant Arrhythmia Ablation." A & A Case Reports 8, no. 11 (June 2017): 282–85. http://dx.doi.org/10.1213/xaa.0000000000000490.

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Gomes, F. A. A., J. B. C. Silva, and A. J. Diniz. "RADIATION HEAT TRANSFER WITH ABLATION IN A FINITE PLATE." Revista de Engenharia Térmica 4, no. 2 (December 31, 2005): 190. http://dx.doi.org/10.5380/reterm.v4i2.5410.

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The phenomenon of ablation is a process of thermal protection with several applications, mainly, in mechanical and aerospace engineering. Ablative thermal protection is applied using special materials (named ablative materials) externally on the surface of a structure in order to isolate it against thermal effects. The ablative phenomenon is a complex process involving phase changes with partial or total loss of the material. So the position of the boundary is initially unknown. The governing equations of the process form a non-linear system of coupled partial differential equations. The one-dimensional analysis of an ablative process on the plate is performed by using the generalized integral transform technique GITT for solution of the system of governing equations. By application of this solution technique, the system of partial differential equations is transformed into a system of infinite ordinary differential equations that can be solved after the truncation of that system by numerical techniques codes available. The plate of finite thickness at constant properties is subjected to a time-dependent prescribed radiation heat flux at one face, initially with a uniform temperature T0, and insulated on the other face. After an initial heating period, ablation starts at the heated surface through melting and continuous removal of the plate material. The results of interest are the thickness and the loss rate of the ablative material. The obtained results are compared with available results from other solution techniques in the literature.

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Kumar, Amit, Chikesh Ranjan, Kaushik Kumar, M. Harinatha Reddy, B. Sridhar Babu, and Jitendra Kumar Katiyar. "State-of-the-Art on Advancements in Carbon–Phenolic and Carbon–Elastomeric Ablatives." Polymers 16, no. 11 (May 22, 2024): 1461. http://dx.doi.org/10.3390/polym16111461.

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Ablative composites serve as sacrificial materials, protecting underlying materials from high-temperature environments by endothermic reactions. These materials undergo various phenomena, including thermal degradation, pyrolysis, gas generation, char formation, erosion, gas flow, and different modes of heat transfer (such as conduction, convection, and radiation), all stemming from these endothermic reactions. These phenomena synergize to form a protective layer over the underlying materials. Carbon, with its superb mechanical properties and various available forms, is highlighted, alongside phenolics known for good adhesion and fabric ability and elastomers valued for flexibility and resilience. This study focuses on recent advancements in carbon-and-phenolic and carbon-and-elastomeric composites, considering factors such as erosion speed; high-temperature resistance; tensile, bending, and compressive strength; fiber–matrix interaction; and char formation. Various authors’ calculations regarding the percentage reduction in linear ablation rate (LAR) and mass ablation rate (MAR) are discussed. These analyses inform potential advancements in the field of carbon/phenolic and carbon/elastomeric ablative composites.

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Schwartz, Ilsa, Patrick J. Antonelli, Kenneth R. Bouchard, and Jack M. Kartush. "Carbon Dioxide Laser Occlusion of the Guinea Pig Posterior Semicircular Canal." Otolaryngology–Head and Neck Surgery 113, no. 4 (October 1995): 453–58. http://dx.doi.org/10.1016/s0194-59989570084-6.

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Preservation of hearing is possible with selective ablation of the vestibular system and mechanical occlusion of the semicircular canals. Complete ablation of all three canals would improve exposure of the internal auditory canal fundus (e.g., for acoustic tumor exposure), but mechanical packing of the vestibule would disrupt normal sound transduction. This study was designed to assess the feasibility of preserving hearing with CO2 laser occlusion, without mechanical packing of the posterior semicircular canal membranous labyrinth. Twenty adult Hartley guinea pigs underwent occlusion of the right posterior semicircular canal with one of three techniques: mechanical packing, laser coagulation, or laser coagulation with mechanical packing. Electrocochleographic thresholds to clicks and 1-kHz and 8-kHz tone bursts did not change significantly 6 weeks after posterior semicircular canal occlusion with any of these techniques. Histopathologic examination revealed complete canal occlusion with all methods. These findings suggest that mechanical occlusion and CO2 laser occlusion of the posterior semicircular canal do not significantly affect cochlear function in the guinea pig. CO2 laser occlusion of the membranous labyrinth may prove useful for more extensive selective vestibular ablation by obviating the need for mechanical packing of the labyrinth.

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Zezhong, Shan, Liu Xuyu, Lu Xiang, Ma Kai, Xiao Haijian, and Tian Minghui. "Analysis of lightning ablation damage of composite laminates with multiple fasteners." Advances in Mechanical Engineering 14, no. 11 (November 2022): 168781322211372. http://dx.doi.org/10.1177/16878132221137215.

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Composite materials have been widely used in civil aviation aircraft, but a large area of ablation damage occurs after lightning strikes, which threatens the operation safety of civil aviation aircraft. The composite material is fixed by multiple fasteners. The different installation positions of fasteners have a great influence on the result of lightning damage of composite. Based on these, a lightning ablation damage model of laminates with multiple fasteners is established, and the accuracy of the model is verified by comparing with the results in the references. In addition, the effect of different installation methods of multiple fasteners on the lightning ablation damage of laminates is studied. The results show that the number of fasteners is not the decisive factor among the factors that affect the ablation damage of laminates with multiple fasteners, and the installation layout of fasteners has an important impact on the damage results. When the fiber direction and aspect ratio of the laminate are the same, the maximum ablation damage area of terrible fasteners layout is 1.27 times the minimum ablation damage area of best fasteners layout under the action of lightning peak current of 200 kA.

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Gao, Meng Jiao, Lai Chen, Yong Sheng Hua, Jia Bao Zhang, Jian Feng Pan, Chun Jie Zhou, Mu Su Ren, and Jin Liang Sun. "Ablation Properties of C/C-ZrC-SiC Composites by the Precursor Infiltration Pyrolysis." Advanced Materials Research 239-242 (May 2011): 1076–81. http://dx.doi.org/10.4028/www.scientific.net/amr.239-242.1076.

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The ablation properties of C/C-ZrC-SiC composites prepared by precursor infiltration and pyrolysis processes were studied by the H2-O2 ablation method. The results indicate that the ablation rate of C/C-ZrC-SiC composites decreases with increasing density of the composites. The linear ablation rate and mass ablation rate of the C/C-ZrC-SiC composites (ρ=1.69g·cm-3) were 0.00211mm·s-1 and 0.5179mg·s-1, only 20.6% and 31.6% of those of C/C composites (ρ=1.78g·cm-3) respectively. The introduction of ZrC-SiC into the matrix greatly enhanced the anti-oxidative and ablation property of the C/C composite. The ablation mechanisms of the C/C-ZrC-SiC composites were supposed to be the synergistic effects of thermo-chemistry ablation (oxidation and sublimation) and mechanical erosion.

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Song, Jiuqiang, Zhixiong Huang, Yan Qin, Honghua Wang, and Minxian Shi. "Effects of Zirconium Silicide on the Vulcanization, Mechanical and Ablation Resistance Properties of Ceramifiable Silicone Rubber Composites." Polymers 12, no. 2 (February 24, 2020): 496. http://dx.doi.org/10.3390/polym12020496.

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Ceramifiable silicone rubber composites play important roles in the field of thermal protection systems (TPS) for rocket motor cases due to their advantages. Ceramifiable silicone rubber composites filled with different contents of ZrSi2 were prepared in this paper. The fffects of ZrSi2 on the vulcanization, mechanical and ablation resistance properties of the composites were also investigated. The results showed that the introduction of ZrSi2 decreased the vulcanization time of silicone rubber. FTIR spectra showed that ZrSi2 did not participate in reactions of the functional groups of silicone rubber. With the increasing content of ZrSi2, the tensile strength increased first and then decreased. The elongation at break decreased and the permanent deformation increased gradually. The thermal conductivity of the composite increased from 0.553 W/(m·K) to 0.694 W/(m·K) as the content of the ZrSi2 increased from 0 to 40 phr. In addition, the thermal conductivity of the composite decreased with the increase of temperature. Moreover, thermal analysis showed that the addition of ZrSi2 increased the initial decomposition temperature of the composite, but had little effect on the peak decomposition temperature in nitrogen. However, the thermal decomposition temperature of the composite in air was lower than that in nitrogen. The addition of ZrSi2 decreased the linear and mass ablation rate, which improved the ablative resistance of the composite. With the ZrSi2 content of 30 phr, the linear and mass ablation rate were 0.041 mm/s and 0.029 g/s, decreasing by 57.5% and 46.3% compared with the composite without ZrSi2, respectively. Consequently, the ceramifiable silicone rubber composite filled with ZrSi2 is very promising for TPS.

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Mu, Qiu Hong, Dan Peng, Jin Hui Li, and Feng Wang. "Preparation and Properties of VPCS/PMPS Composites." Solid State Phenomena 329 (March 25, 2022): 3–8. http://dx.doi.org/10.4028/p-ej73po.

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VPCS with [Si-CH2-CH2-Si] structure were synthesized through hydrosilylation reaction of divinyldimethylsilane and diphenylsilane. VPCS were mixed with additive liquid PMPS silicone rubber and VPCS/PMPS based ablative composites were also prepared. VPCS play an important role in improving the thermal stability of PMPS. The 10% weight loss of VPCS/PMPS is 530.6°C, and Tmax is at 601.3°C, 43°C and 48°C higher than PMPS. Anti-ablation fillers have great important on composites. VPCS/PMPS/ZrB2 showed higher mechanical properties and ablative resistance, which is accordance with the results of SEM morphology observation.

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Okada, Seigo, Jun Muneuchi, and Hideki Origuchi. "Characterisation of three-dimensional mapping in Wolff–Parkinson–White syndrome with septal aneurysmal dyskinesis." Cardiology in the Young 28, no. 1 (August 29, 2017): 168–70. http://dx.doi.org/10.1017/s1047951117001779.

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AbstractA 21-year-old man with Wolff–Parkinson–White syndrome and aneurysmal septal dyskinesis underwent radiofrequency catheter ablation of the accessory pathways. Before radiofrequency catheter ablation, the activation wavefront arose from the aneurysmal septum, whereas the propagation of the left ventricle was normalised after radiofrequency catheter ablation. These findings demonstrate the importance of the electro-mechanical interaction in patients with Wolff–Parkinson–White syndrome and ventricular dysfunction.

Journal articles on the topic 'Mechanical ablation'

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