The Energy Stored in the Aluminum Nanopowder Irradiated by Electron Beam

2016 ◽  
Vol 685 ◽  
pp. 639-642 ◽  
Author(s):  
Andrei V. Mostovshchikov ◽  
Alexander P. Ilyin ◽  
Alexander A. Azanov ◽  
Ivan S. Egorov
Keyword(s):  
Electron Beam ◽  
Radiation Dose ◽  
Thermal Effect ◽  
Absorbed Dose ◽  
Aluminum Nanopowder ◽  
Degree Of Oxidation ◽  
Oxidation Stage ◽  
Nanopowder Oxidation ◽  
Motivating Factor ◽  
Two Stages

The influence of the electron beam irradiation on the parameters of aluminum nanopowder oxidation by heating in air was studied. It was found that the oxidation starts at the temperature in the range from 410° C to 460° C and independent on the radiation dose. The degree of oxidation varied from 44.4 % to 58.3 % and its dependence on the radiation dose was not established. The heat energy release occurred in two stages: at the first stage (up to ~ 660° C) in general the increase of the thermal effect was observed. At the second oxidation stage of irradiated aluminum nanopowder the growth of the thermal effect also observed. The peak of heat effect achieved by irradiation (45.0 kGy absorbed dose) was 2576 J/g higher than the thermal effect for non-irradiated aluminum nanopowder. The energy stored is an additional motivating factor in the synthesis of composite materials, intermetallic compounds, hydrogen producing reactions and synthesis of various kinds.

Effect of electron beam radiation dose on the foam formation in pre-ceramic polymer

2010 ◽  
Vol 79 (3) ◽  
pp. 301-305 ◽  
Author(s):  
Rosa Maria da Rocha ◽  
Esperidiana A.B. Moura ◽  
José Carlos Bressiani ◽  
Ana Helena A. Bressiani
Keyword(s):  
Electron Beam ◽  
Radiation Dose ◽  
Foam Formation ◽  
Beam Radiation ◽  
Electron Beam Radiation

scholarly journals Is nuclear medicine really safe?

2002 ◽  
Vol 45 (spe) ◽  
pp. 115-118
Author(s):  
Nicole Colas-Linhart
Keyword(s):  
Nuclear Medicine ◽  
Human Serum Albumin ◽  
Radiation Dose ◽  
Serum Albumin ◽  
Human Serum ◽  
Absorbed Dose ◽  
Cellular Level ◽  
Whole Body ◽  
Absorbed Doses ◽  
Standard Models

In nuclear medicine, radiation absorbed dose estimates calculated by standard models at the whole body or organ are very low. At cellular level, however, the heterogeneity of radionuclide distributions of radiation dose patterns may be significant. We present here absorbed doses at cellular level and evaluate their possible impact on the usually assumed risk/benefit relationships in nuclear medicine studies. The absorbed dose values calculated are surprisingly high, and are difficult to interpret. In the present study, we show calculated doses at the cellular level and discuss possible biological consequences, for two radiopharmaceuticals labelled with technetium-99m: human serum albumin microspheres used for pulmonary scintigrapies and HMPAO used to labelled leukocytes.

Radiation Dose to Patients and Personnel during Fluoroscopy at Percutaneous Renal Stone Extraction

1989 ◽  
Vol 30 (2) ◽  
pp. 201-206 ◽  
Author(s):  
K. Geterud ◽  
A. Larsson ◽  
S. Mattsson
Keyword(s):  
Radiation Dose ◽  
Effective Dose ◽  
Renal Stone ◽  
Absorbed Dose ◽  
Effective Dose Equivalent ◽  
Dose Equivalent ◽  
Organ Doses ◽  
The Mean ◽  
Total Effective Dose Equivalent ◽  
Total Effective Dose

The radiation dose to patients and personnel was estimated during 11 percutaneous renal stone extractions. For the patients the energy imparted, the mean absorbed dose to various organs, and the effective dose equivalent were estimated. For different personnel categories some organ doses and the effective dose equivalent were also estimated. Large differences in the radiation dose between patients were observed. The mean effective dose equivalent to the patient was 4.2 (range 0.6–8.3) mSv, and the energy imparted 285 (range 50–500) mJ. These figures are comparable to those reported for routine colon examination and urography. For the personnel there were also large differences between individuals and categories. The highest radiation dose was received by the radiologist. It was estimated that a radiologist who performs 150 percutaneous renal stone extractions per year will receive a yearly contribution to his/her effective dose equivalent of 2.4 mSv. Even when the contribution from other diagnostic and interventional radiologic procedures is added, the total effective dose equivalent hardly exceeds 5 mSv or 1/10 of the present dose limit for persons engaged in radiologic work. For the hands of the radiologist there is a risk of doses closer to the present limit for single organs or tissues of 500 mSv/year.

Electron Beam Initiated Grafting and Crosslinking of Ethylene Vinyl Acetate Copolymer. Part-I: Structural Characterization

1996 ◽  
Vol 69 (1) ◽  
pp. 120-129 ◽  
Author(s):  
Sujit K. Datta ◽  
Tapan K. Chaki ◽  
Anil K. Bhowmick
Keyword(s):  
Electron Beam ◽  
Radiation Dose ◽  
Vinyl Acetate ◽  
Ethylene Vinyl Acetate ◽  
Carbonyl Groups ◽  
Gel Content ◽  
Lower Radiation Dose ◽  
Absorbance Peak ◽  
Crosslinking Reactions ◽  
Acetate Copolymer

Abstract Electron beam irradiation of Ethylene vinyl acetate, EVA (VA content 12, 28 & 45%) copolymer was carried out in presence of trimethylolpropane trimethacrylate (TMPTMA) and triallyl cyanurate (TAC) and the structure of the modified copolymers was determined with the help of IR spectroscopy and gel content measurements. The IR absorbance peak at 1640 cm−1 disappears at lower radiation dose indicating that the grafting and crosslinking reactions take place through double bonds. Some carbonyl groups are formed during irradiation. The concentration of carbonyl group increases with the radiation dose and the level of multifunctional monomers. The grafting level of TAC onto EVA determined from IR absorbance peak at 1565 cmx−1 remains almost constant with the variation of radiation dose and increases with TAC level. The gel content increases with radiation dose, but changes marginally with TMPTMA and TAC levels. The percent gel content increases linearly with vinyl acetate content in EVA.

scholarly journals Percutaneous Coronary Intervention in Pregnancy: Modeling of the Fetal Absorbed Dose

2019 ◽  
Vol 2019 ◽  
pp. 1-5 ◽  
Author(s):  
Kfier Kuba ◽  
Diana Wolfe ◽  
Alan H. Schoenfeld ◽  
Anna E. Bortnick
Keyword(s):  
Myocardial Infarction ◽  
Percutaneous Coronary Intervention ◽  
Radiation Dose ◽  
Absorbed Dose ◽  
Coronary Intervention ◽  
Cardiac Procedures ◽  
Percutaneous Coronary ◽  
St Elevation ◽  
Absorbed Radiation Dose ◽  
In Pregnancy

There is a gap in the literature regarding fetal radiation exposure from interventional cardiac procedures. With an increasingly large and complex cohort of pregnant cardiac patients, it is necessary to evaluate the safety of invasive cardiac procedures and interventions in this population. Here we present a case of a patient with multiple medical comorbidities and non-ST elevation myocardial infarction (NSTEMI) at 15 weeks’ gestation, managed with percutaneous coronary intervention (PCI). We were able to minimize the maternal and estimated fetal absorbed radiation dose to <1 milliGray (mGy), significantly less than the threshold dose for fetal adverse effects at this gestational age.

scholarly journals Application of Dynamic Beam Positioning for Creating Specified Structures and Properties of Welded Joints in Electron-Beam Welding

Materials ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2233
Author(s):  
Tatyana Olshanskaya ◽  
Vladimir Belenkiy ◽  
Elena Fedoseeva ◽  
Elena Koleva ◽  
Dmitriy Trushnikov
Keyword(s):  
Mechanical Properties ◽  
Electron Beam ◽  
Weld Metal ◽  
Thermal Effect ◽  
Welded Joints ◽  
Electron Beam Welding ◽  
Welded Joint ◽  
Parent Metal ◽  
Cooling Rates ◽  
Structures And Properties

The application of electron beam sweep makes it possible to carry out multifocal and multi-beam welding, as well as combine the welding process with local heating or subsequent heat treatment, which is important when preparing products from thermally-hardened materials. This paper presents a method of electron beam welding (EBW) with dynamic beam positioning and its experimental-calculation results regarding the formation of structures and properties of heat-resistant steel welded joints (grade of steel 20Cr3MoWV). The application of electron beam oscillations in welding makes it possible to change the shape and dimensions of welding pool. It also affects the crystallization and formation of a primary structure. It has been established that EBW with dynamic beam positioning increases the weld metal residence time and the thermal effect zone above the critical A3 point, increases cooling time and considerably reduces instantaneous cooling rates as compared to welding without beam sweep. Also, the difference between cooling rates in the depth of a welded joint considerably reduces the degree of structural non-uniformity. A bainitic–martensitic structure is formed in the weld metal and the thermal effect zone throughout the whole depth of fusion. As a result of this structure, the level of mechanical properties of a welded joint produced from EBW with dynamic electron beam positioning approaches that of parent metal to a greater extent than in the case of welding by a static beam. As a consequence, welding of heat-resistant steels reduces the degree of non-uniformity of mechanical properties in the depth of welded joints, as well as decreases the level of hardening of a welded joint in relation to parent metal.

scholarly journals Influences of Absorbed Dose Rate on the Mechanical Properties and Fiber–Matrix Interaction of High-Density Polyethylene-Based Carbon Fiber Reinforced Thermoplastic Irradiated by Electron-Beam

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3012
Author(s):  
Se Kye Park ◽  
Dong Yun Choi ◽  
Duyoung Choi ◽  
Dong Yun Lee ◽  
Seung Hwa Yoo
Keyword(s):  
Mechanical Properties ◽  
Electron Beam ◽  
Carbon Fiber ◽  
Dose Rate ◽  
High Density Polyethylene ◽  
Absorbed Dose ◽  
High Density ◽  
Absorbed Dose Rate ◽  
Dose Rates ◽  
Absorbed Dose Rates

In this study, a high-density polyethylene (HDPE)-based carbon fiber-reinforced thermoplastic (CFRTP) was irradiated by an electron-beam. To assess the absorbed dose rate influence on its mechanical properties, the beam energy and absorbed dose were fixed, while the absorbed dose rates were varied. The tensile strength (TS) and Young’s modulus (YM) were evaluated. The irradiated CFRTP TS increased at absorbed dose rates of up to 6.8 kGy/s and decreased at higher rates. YM showed no meaningful differences. For CFRTPs constituents, the carbon fiber (CF) TS gradually increased, while the HDPE TS decreased slightly as the absorbed dose rates increased. The OH intermolecular bond was strongly developed in irradiated CFRTP at low absorbed dose rates and gradually declined when increasing those rates. X-ray photoelectron spectroscopy analysis revealed that the oxygen content of irradiated CFRTPs decreased with increasing absorbed dose rate due to the shorter irradiation time at higher dose rates. In conclusion, from the TS viewpoint, opposite effects occurred when increasing the absorbed dose rate: a favorable increase in CF TS and adverse decline of attractive hydrogen bonding interactions between HDPE and CF for CFRTPs TS. Therefore, the irradiated CFRTP TS was maximized at an optimum absorbed dose rate of 6.8 kGy/s.

scholarly journals Novel Organic Material Induced by Electron Beam Irradiation for Medical Application

Polymers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 306 ◽  
Author(s):  
Adrian Barylski ◽  
Krzysztof Aniołek ◽  
Andrzej S. Swinarew ◽  
Sławomir Kaptacz ◽  
Jadwiga Gabor ◽  
...  
Keyword(s):  
Electron Beam ◽  
Electron Beam Irradiation ◽  
Absorbed Dose ◽  
Medical Application ◽  
High Energy ◽  
Polymer Chains ◽  
Degree Of Crystallinity ◽  
Beam Irradiation ◽  
The Impact ◽  
The Degree Of Crystallinity

This study analyzed the effects of irradiation of polytetrafluoroethylene (PTFE) containing 40% of bronze using an electron beam with energy of 10 MeV. Dosages from 26 to156 kGy (2.6–15.6 Mrad) were used. The impact of a high-energy electron beam on the thermal, spectrophotometric, mechanical, and tribological properties was determined, and the results were compared with those obtained for pure PTFE. Thermal properties studies showed that such irradiation caused changes in melting temperature Tm and crystallization temperature Tc, an increase in crystallization heat ∆Hc, and a large increase in crystallinity χc proportional to the absorbed dose for both polymers. The addition of bronze decreased the degree of crystallinity of PTFE by twofold. Infrared spectroscopy (FTIR) studies confirmed that the main phenomenon associated with electron beam irradiation was the photodegradation of the polymer chains for both PTFE containing bronze and pure PTFE. This had a direct effect on the increase in the degree of crystallinity observed in DSC studies. The use of a bronze additive could lead to energy dissipation over the additive particles. An increase in hardness H and Young’s modulus E was also observed. The addition of bronze and the irradiation with an electron beam improved of the operational properties of PTFE.

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