Surface modification of WC—3% Co hard alloy by powerful nanosecond ultraviolet laser pulses

The surface quality of the WC—3% Co hard alloy after modification by focused beams of an ultraviolet laser has been investigated. At radiation energy density E ≥ 1.6 J / cm2, traces of melting with a size of 1—3 μm were found on the alloy surface in the impact zone. An increase in intensity of the incident radiation to E ≈ 6.2 J / cm2 leads to an increase in the concentration of cobalt on the surface from 7 to 10%, while the concentration of carbon decreases from 33 to 18%.

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Effect of pulsed soft X-ray radiation on the surface topography of some metals

Journal of Physics Conference Series ◽

10.1088/1742-6596/2064/1/012092 ◽

2021 ◽

Vol 2064 (1) ◽

pp. 012092

Author(s):

A E Ligachev ◽

M V Zhidkov ◽

S A Sorokin ◽

G V Potemkin ◽

Yu R Kolobov

Keyword(s):

Surface Topography ◽

Surface Defects ◽

Radiation Energy ◽

High Current ◽

Radiation Energy Density ◽

Near Surface ◽

Ion Flow ◽

X Ray ◽

Irradiation Energy ◽

The Impact

Abstract Effect of the pulsed soft X-ray fluxes (PSXF) on the surface topography of metals (Mg and Cu) has been investigated. Soft pulse X-ray irradiation (energy quanta of 0.1-1.0 keV) were carried out on a high-current MIG generator. The sample of magnesium was located at a distance of 10 cm from the X-ray source. Since the distance to the sample significantly exceeded the size of the X-ray beam, it can be assumed that the density of the X-ray radiation flow to the magnesium sample was uniform. The duration of the radiation pulse was 100 ns, and the radiation energy density in the pulse varied from 13 to 19 J/cm2. As a result of melting under the action of PSXF of the near-surface layer of metals and subsequent solidification, a wavy relief is formed on their surface. Defects in the form of craters, which usually occur after the impact of a powerful pulsed ion flow on metals, were not detected.

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The influence of periodical, interference laser micromachining on nano-crystallization of amorphous magnetic ribbons

Photonics Letters of Poland ◽

10.4302/plp.v9i3.762 ◽

2017 ◽

Vol 9 (3) ◽

pp. 91 ◽

Cited By ~ 2

Author(s):

Roman Ostrowski ◽

Jan Kusiński ◽

Krzysztof Czyż ◽

Antoni Rycyk ◽

Antoni Sarzyński ◽

...

Keyword(s):

Periodic Structures ◽

Radiation Energy ◽

Laser Pulses ◽

Atom Probe ◽

Chem Phys ◽

Biomedical Science ◽

Soft Magnetic ◽

Magnetic Alloys ◽

Radiation Energy Density ◽

Micro Structuring

The main problem connected with crystallization of amorphous magnetic materials from the FeSiB(X) group is the increase of their fragility with the increasing content of crystalline phase. To overcome this defect the possibilities offered by the interference, pulse laser heating of FeSiB ribbons were utilized. A simple, interference prismatic system at the output of Nd:YAG laser (8-10 ns, 2 J, 1064 nm) was used. The investigations included the influence of laser radiation energy density, number of laser pulses and their periodical, spatial surface arrangement on the crystallization process. Full Text: PDF ReferencesY.R. Zhang and R.V. Ramanujan, "A study of the crystallization behavior of an amorphous Fe77.5Si13.5B9 alloy", Mater. Sci. Eng. A 416, 161 (2006). CrossRef T. Alam, T. Borkar, S. Joshi, S. Katakamb, X. Chenc and N.B. Dahotre, "Influence of niobium on laser de-vitrification of Fe-Si-B based amorphous magnetic alloys", J. Non-Cryst. Solids 428, 75 (2015). CrossRef K.G. Pradeep, G. Herzer, P. Choi and D. Raabe, "Atom probe tomography study of ultrahigh nanocrystallization rates in FeSiNbBCu soft magnetic amorphous alloys on rapid annealing", Acta Mater. 68, 295 (2014). CrossRef S. Katakam, J.Y. Hwang, H. Vora, S.P. Harimkar, R. Banerjee and N.B. Dahotre, "Laser-induced thermal and spatial nanocrystallization of amorphous Fe-Si-B alloy", Scr. Mater. 66, 538 (2012). CrossRef J. Kusiński, A. Sypień, G. Kusiński and C. Nilson, "Microstructure and nanochemistry of Ca-doped cobalt oxide single crystals", Mat. Chem. Phys. 81, 390 (2003). CrossRef C. Smith, S. Katakam, S. Nag, X. Chen, R.V. Ramanujan, N.B. Dahotre and R. Banerjee, "Improved soft magnetic properties by laser de-vitrification of Fe-Si-B amorphous magnetic alloys", Mater. Lett. 122, 155 (2014). CrossRef Ch. Lu and R. H. Lipson, "Interference lithography: a powerful tool for fabricating periodic structures", Laser Photonics Rev. 4, 568 (2010). CrossRef K. Czyż, J. Marczak, R. Major, A. Mzyk, A. Rycyk, A. Sarzyński and M. Strzelec, "Selected laser methods for surface structuring of biocompatible diamond-like carbon layers", Diam. Relat. Mater. 67, 26 (2016). CrossRef A. Sarzyński, J. Marczak, M. Strzelec, A. Rycyk, K. Czyż and D. Chmielewska, "Laser micro-structuring of surfaces for applications in materials and biomedical science", Proc. SPIE, 10159, 101590A (2016). CrossRef

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Спектральные характеристики свечения поверхности частиц каменных углей во время воздействия лазерных импульсов в режиме свободной генерации

Журнал технической физики ◽

10.21883/os.2020.12.50327.187-20 ◽

2020 ◽

Vol 128 (12) ◽

pp. 1898

Author(s):

Б.П. Адуев ◽

Д.Р. Нурмухаметов ◽

Я.В. Крафт ◽

З.P. Исмагилов

Keyword(s):

Energy Density ◽

Laser Pulse ◽

Pulse Energy ◽

Laser Pulse Energy ◽

Emission Spectra ◽

Radiation Energy ◽

Laser Pulses ◽

Radiation Energy Density ◽

Pulse Energy Density ◽

Coal Particles

In this work, we investigated the glow spectra of coal fractions with dimensions 63 μm directly during the action of neodymium laser pulses (120 μs). Depending on the radiation energy density H, the emission spectra have a different character. The glow at the minimum values of the laser pulse energy density Hcr (1) is associated with the ignition of small coal particles (~ 1 μm) present in the fractions and the ignition of reactive microprotrusions on the surface of the larger coal particles. The glow spectra at this stage are of a non-thermal nature and are associated with the emission of molecules of volatile substances in the gas phase and the products of their oxidation. With an increase in the laser pulse energy density H, a thermal glow of the surface of larger coal particles is observed, which is described by the Planck formula at T = 3100 K. When H = Hcr (2) is reached, the surface of the coal particles is ignited during the action of the laser pulse. Contributions to the spectra are the glow of the surface of coal particles, emitted carbon particles, and the glow associated with the emission of excited molecules H2, H2O, CO2. With an increase in H> Hcr (2), the processes leading to the glow of coal particles during a laser pulse are similar to those described above for Hcr (2), but the glow intensity increases

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Adverse Features of Rectourethral Fistula Requiring Extirpative Surgery and Permanent Dual Diversion: Our Experience and Recommendations

Journal of Clinical Medicine ◽

10.3390/jcm10174014 ◽

2021 ◽

Vol 10 (17) ◽

pp. 4014

Author(s):

Francisco E. Martins ◽

João Felicio ◽

Tiago Ribeiro Oliveira ◽

Natália Martins ◽

Vítor Oliveira ◽

...

Keyword(s):

Radiation Energy ◽

Primary Treatment ◽

Rectourethral Fistula ◽

Surgical Approaches ◽

Cancer Treatments ◽

Suprapubic Cystostomy ◽

Pelvic Cancer ◽

The Impact

Introduction: To report a series of men with a rectourethral fistula (RUF) resulting from pelvic cancer treatments and explore their therapeutic differences and impact on the functional outcomes and quality of life highlighting the adverse features that should determine permanent urinary or dual diversion. Methods: A retrospective database search was performed in four centers to identify patients with RUF resulting from pelvic cancer treatment. Medical records were analyzed for the demographics, comorbidities, diagnostic evaluation, fistula characteristics, surgical approaches and outcomes. The endpoints analyzed included a successful fistula closure following a repair and the impact of the potential adverse features on outcomes. Results: Twenty-three patients, aged 57–79 years (median 68), underwent an RUF reconstruction. The median follow-up (FU) was 54 months (range 18–115). The patients were divided into two groups according to the etiology: radiation/energy-ablation treatments with or without surgery (G1, n = 10) and surgery only (G2, n = 13). All of the patients underwent a temporary diverting colostomy and suprapubic cystostomy. Overall, a successful RUF closure was achieved in 18 (78%) patients. An interposition flap was used in six (60%) patients and one (7.7%) patient in groups G1 and G2, respectively (p = 0.019). The RUF was managed successfully in all 13 patients in group G2 as opposed to 5/10 (50%) in group G1 (p = 0.008). The patients in the radiation/energy-ablation group were more likely to require permanent dual diversion (50% vs. 0%, p < 0.0075). Conclusion: Radiation/energy-ablation therapies are associated with a more severe RUF and more complex reconstructions. Most of these patients require an abdominoperineal approach and flap interposition. The failure of an RUF repair with the need for permanent dual diversion, eventually combined with extirpative surgery, is higher after previous radiation/energy-ablation treatment. Therefore, permanent dual diversion as the primary treatment should always be included in the decision-making process as reconstruction may be futile in specific settings.

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Self-Compassion and Quality of Life in Adults Who Stutter

American Journal of Speech-Language Pathology ◽

10.1044/2020_ajslp-20-00055 ◽

2020 ◽

Vol 29 (4) ◽

pp. 2097-2108

Author(s):

Robyn L. Croft ◽

Courtney T. Byrd

Keyword(s):

Quality Of Life ◽

Social Connectedness ◽

The Self ◽

Future Research ◽

Self Compassion ◽

Adults Who Stutter ◽

And Gender ◽

Relationship Of ◽

The Impact

Purpose The purpose of this study was to identify levels of self-compassion in adults who do and do not stutter and to determine whether self-compassion predicts the impact of stuttering on quality of life in adults who stutter. Method Participants included 140 adults who do and do not stutter matched for age and gender. All participants completed the Self-Compassion Scale. Adults who stutter also completed the Overall Assessment of the Speaker's Experience of Stuttering. Data were analyzed for self-compassion differences between and within adults who do and do not stutter and to predict self-compassion on quality of life in adults who stutter. Results Adults who do and do not stutter exhibited no significant differences in total self-compassion, regardless of participant gender. A simple linear regression of the total self-compassion score and total Overall Assessment of the Speaker's Experience of Stuttering score showed a significant, negative linear relationship of self-compassion predicting the impact of stuttering on quality of life. Conclusions Data suggest that higher levels of self-kindness, mindfulness, and social connectedness (i.e., self-compassion) are related to reduced negative reactions to stuttering, an increased participation in daily communication situations, and an improved overall quality of life. Future research should replicate current findings and identify moderators of the self-compassion–quality of life relationship.

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Surgery for Lung Cancer and the Consequences for the Swallow

Perspectives of the ASHA Special Interest Groups ◽

10.1044/persp1.sig13.162 ◽

2016 ◽

Vol 1 (13) ◽

pp. 162-168

Author(s):

Pippa Hales ◽

Corinne Mossey-Gaston

Keyword(s):

Lung Cancer ◽

Treatment Options ◽

Vocal Cord Palsy ◽

Subsequent Treatment ◽

Physiological Reserve ◽

Palliative Phase ◽

And Function ◽

The Impact ◽

Swallow Function

Lung cancer is one of the most commonly diagnosed cancers across Northern America and Europe. Treatment options offered are dependent on the type of cancer, the location of the tumor, the staging, and the overall health of the person. When surgery for lung cancer is offered, difficulty swallowing is a potential complication that can have several influencing factors. Surgical interaction with the recurrent laryngeal nerve (RLN) can lead to unilateral vocal cord palsy, altering swallow function and safety. Understanding whether the RLN has been preserved, damaged, or sacrificed is integral to understanding the effect on the swallow and the subsequent treatment options available. There is also the risk of post-surgical reduction of physiological reserve, which can reduce the strength and function of the swallow in addition to any surgery specific complications. As lung cancer has a limited prognosis, the clinician must also factor in the palliative phase, as this can further increase the burden of an already compromised swallow. By understanding the surgery and the implications this may have for the swallow, there is the potential to reduce the impact of post-surgical complications and so improve quality of life (QOL) for people with lung cancer.

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