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Metal additive manufacturing technologies provide new opportunities for manufacturing complex components. However, the limited data on fracture behavior are delaying adoption in safe‐critical applications. This paper aims to evaluate the effect of orientation and the intra‐build design parameters on EBM Ti6Al4V fracture toughness using a design of experiments. Three builds comprised of over 150 compact tension samples were printed representative of the EBM build chamber, followed by microstructural characterization, X‐ray microcomputed tomography, and fracture toughness testing per ASTM E399. The average fracture toughness was 65 MPa√m, with anisotropy as the largest source of variation due to crack growth behavior with respect to the build direction. Microstructure coarsening was observed with increase in height, resulting in an increase in fracture toughness, irrespective of sample geometry or orientation. Build orientation and sample location influenced the microstructure and fracture toughness and should be considered when adopting EBM components in load‐bearing applications. Highlights: The effect of intra‐build parameters on EBM Ti6Al4V fracture toughness is investigated.The fracture toughness reported 10% variation, comparable to cast and wrought alloys.Response surface methodology helped identify factors effecting fracture toughness.Anisotropy was the biggest source of variation, affected by build orientation. [ABSTRACT FROM AUTHOR]

Abstract Background Postoperative radiotherapy can significantly reduce keloid recurrence. However, consensus on the optimal radiotherapy dose and treatment schedule remains elusive. This study aims to evaluate the effectiveness of surgery followed by a short-course of radiotherapy administered every other day for keloid treatment. Materials/Methods We conducted a retrospective analysis of 498 patients with keloids treated at our institution between January 2010 and December 2017. All patients underwent electron beam irradiation at a dose of 16 Gy, delivered in four fractions every other day, starting within 24 h post-surgery. The primary endpoint of the study was the local control rate. Results A total of 130 (26.5%) keloids recurred after a median follow-up of 68.1months (42.6-129.9 months). The local control rates at 1 year, 3 years and 5 years for all patients were 89.5%, 82.5% and 81%, respectively. The highest recurrence rate was observed in keloids located in the chest region (50.8%), followed by the suprapubic (47.8%), head and neck (38.8%), limbs (33.3%) and ear (14%). Both multivariate and univariate analyses identified the presence of pain and or pruritus as an independently prognostic factor for keloid recurrence (p

Background: Postoperative radiotherapy can significantly reduce keloid recurrence. However, consensus on the optimal radiotherapy dose and treatment schedule remains elusive. This study aims to evaluate the effectiveness of surgery followed by a short-course of radiotherapy administered every other day for keloid treatment. Materials/Methods: We conducted a retrospective analysis of 498 patients with keloids treated at our institution between January 2010 and December 2017. All patients underwent electron beam irradiation at a dose of 16 Gy, delivered in four fractions every other day, starting within 24 h post-surgery. The primary endpoint of the study was the local control rate. Results: A total of 130 (26.5%) keloids recurred after a median follow-up of 68.1months (42.6-129.9 months). The local control rates at 1 year, 3 years and 5 years for all patients were 89.5%, 82.5% and 81%, respectively. The highest recurrence rate was observed in keloids located in the chest region (50.8%), followed by the suprapubic (47.8%), head and neck (38.8%), limbs (33.3%) and ear (14%). Both multivariate and univariate analyses identified the presence of pain and or pruritus as an independently prognostic factor for keloid recurrence (p<0.0001). The local control rates at 1-year, 3-years and 5-years for patients with or without symptom of pain or pruritus were 45% vs. 98.8%, 12.5% vs. 95.9%, and 8.8% vs. 95%, respectively (HR:37.829, 95%CI: 24.385–58.686, p<0.001). In the ear keloid subgroup, the 1-year, 3-year and 5-year local control rates for patients with pruritus were significantly lower than those without pain or pruritus (60.0% vs. 97.9%, 26.7% vs. 94.7%, 26.7% vs. 94.3%, HR:30.209, 95% CI:14.793–61.69, p<0.001). The same results were found in other location(p<0.001). During treatment and follow-up, two patients experienced infections, and one patient developed a cutaneous fibroblastoma. Conclusion: This study suggests that a combination of surgery followed by short-course, every-other-day radiotherapy can yield satisfactory local control rates for keloids. Pain and or pruritus symptom was an independently prognostic factors for recurrence of keloid. To further validate these results, a prospective randomized controlled trial is recommended. [ABSTRACT FROM AUTHOR]

The widespread detection of per- and polyfluoroalkyl substances (PFAS) in environmental compartments across the globe has raised several health concerns. Destructive technologies that aim to transform these recalcitrant PFAS into less toxic, more manageable products, are gaining impetus to address this problem. In this study , a 9 MeV electron beam accelerator was utilized to treat a suite of PFAS (perfluoroalkyl carboxylates: PFCAs, perfluoroalkyl sulfonates, and 6:2 fluorotelomer sulfonate: FTS) at environmentally relevant levels in water under different operating and water quality conditions. Although perfluorooctanoic acid and perfluorooctane sulfonic acid showed >90% degradation at <500 kGy dose at optimized conditions, a fluoride mass balance revealed that complete defluorination occurred only at/or near 1000 kGy. Non-target and suspect screening revealed additional degradation pathways differing from previously reported mechanisms. Treatment of PFAS mixtures in deionized water and groundwater matrices showed that FTS was preferentially degraded (∼90%), followed by partial degradation of long-chain PFAS (∼15–60%) and a simultaneous increase of short-chain PFAS (up to 20%) with increasing doses. The increase was much higher (up to 3.5X) in groundwaters compared to deionized water due to the presence of PFAS precursors as confirmed by total oxidizable precursor (TOP) assay. TOP assay of e-beam treated samples did not show any increase in PFCAs, confirming that e-beam was effective in also degrading precursors. This study provides an improved understanding of the mechanism of PFAS degradation and revealed that short-chain PFAS are more resistant to defluorination and their levels and regulation in the environment will determine the operating conditions of e-beam and other PFAS treatment technologies. [Display omitted] • Degradation of per- and polyfluoroalkyl substances is influenced by e aq − abundance. • Perfluorobutane sulfonate displayed highest resistance to degradation. • Precursors of per- and polyfluoroalkyl substances were simultaneously oxidized. • Components of the sample matrix affected degradation trends. • Electrical energy per order values in water ranged from 45 to 504 kWh/m3/order. The degradation of a suite of PFAS by e-beam irradiation was studied and the degradation pathways were elucidated. Short-chain PFAS were highly resistant to degradation and required more energy to degrade. [ABSTRACT FROM AUTHOR]

This project was carried out to study the effect of five different doses of electron-beam irradiation, including: 0 as control, 1.5, 3.5, 5.5 and 7.5 kGy on peroxidase (POD), superoxide dismutase (SOD) and polyphenol oxidase (PPO) activities of brown button mushroom (Agaricus brunnescens). The experiment was conducted using an electron beam accelerator (ESS-010-03) and measurements were made during 1, 4th, 8th, 12th and 16th day storage at 4 °C and 80 percent relative humidity. There was a significant difference between irradiated and non-irradiated (control) mushrooms in different enzymes (P

Botryococcus sp. is an economically important microalgae as it contains carbohydrates, lipids, proteins, and a number of phytochemicals. The high concentrations of saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) in this strain also a valuable source for production of biofuel. Mutagenic engineering using irradiation has been known to increase the content of these biomass. The aim of this study is to know the effect of electron-beam irradiation to the growth profile and fatty acid composition of Botryococcus sp. In this study, Botryococcus sp. adjusted an optical density 1.0 after being exposed to different doses of electron-beam irradiation (160 kGy, 240 kGy, and 320 kGy) and induced random mutagenesis for strain improvement was observed based on high energy (1.5 MeV and 2 mA). Several mutants obtained were designated as strain B160, B240, and B320, respectively. The profile growth was significantly different between control (0 kGy) and irradiated microalgae strain. The highest growth is found in B320 mutant. Fatty acid of Botryococcus sp. control produced 7 fatty acids, B160 produced 7 fatty acids, B240 produced 6 fatty acids, whereas B320 produced 9 fatty acids. B320 produced hydrocarbon and phtalic acid as well as fatty acids. Total SFAs and MUFAs of B240 was increased 1.6 times compared to the wild type. The results would give some implications to improve the quality of biodiesel from Botryococcus sp.

Radiation is used for different purposes such as sterilization, imaging, analysis and security. Sterilization, one of the the using area of radiation, is important issue for industries. The disadvantages of heat and chemical sterilization on medicines, medical devices and foodstuffs have made important the use of radiation sterilization. Officinal sterilization method are available (25 kGy gamma-rays) in the pharmacopeias. Other ionizing radiations are getting popular because of their advantages and changing conditions on gamma-sterilization. In this article, the results of different types of ionizing radiation exposure in different doses and several analytical methods used to detect differences have been evaluated. [ABSTRACT FROM AUTHOR]

Highlights • Gaseous wet CH 3 I can become entrapped in interstitial positions in a silica-gel network. • Methylations of amine (in PEDA) and silanol (in surface) through the introduced gaseous wet CH 3 I are observed. • 270 kGy ionizing radiation of electron-beam causes propylethylenediamine in hybrid silica gels fragment. • Ag nanoparticles do not seem to directly react with CH 3 I to produce AgI in our experimental conditions. • Interactions between Ag nanoparticles and propylethylenediamine enhance the Raman signals significantly. Abstract Electron-beam (e-beam) irradiation (270 kGy), applied to Ag nanoparticle (Ag NP) production, causes a chain cleavage of propylethylenediamine in a Ag NP-embedded propylethylenediamine-anchored SiO 2 gel (Ag NP-PEDA gel) network, releasing some volatile organic compounds (VOCs) by thermalizing the gel at 150 °C. The introduced gaseous wet CH 3 I can become entrapped in interstitial positions and can surround the Ag NPs, the remaining organics, or the Ag NP-amine in a silica-gel network, and another CH 3 I was found to form a methoxy species, Si OCH 3 , on the silica surface with the iodine leaving group (I−) not being chemically detected. The interactions between Ag NPs and N donor (of amine) and between amine and the methyl group (of CH 3 I) were confirmed respectively. Ag NPs do not seem to directly produce AgI with CH 3 I under our experimental conditions. Significantly enhanced Raman signals, strong emissions, interesting but different results between Fourier transform infrared (FT-IR) and attenuated total reflectance (ATR) spectroscopy data, and newly released VOCs were all described to support the interaction properties between the very low concentration of gaseous wet CH 3 I and the prepared Ag NP-PEDA gel under the controlled experimental conditions. [ABSTRACT FROM AUTHOR]

Measurements of three-dimensional (3D) dose distribution of electron-beams in water are important for high-energy electron beams from medical linear accelerators (LINAC). Although ionization chambers are commonly used for this purpose, measurements take a long time for precise 3D dose distribution. To solve the problem, we tried the measurements of the 3D dose distributions using a scintillator plate combined with a mirror. After we placed a 1 mm thick plastic scintillator plate at the upper inside of a black box, a water phantom was set above the plastic scintillator plate outside the black box, and electron beam was irradiated to the water phantom from the upper side. The attenuated electron-beam by the water in the phantom was detected by the plastic scintillator plate and the scintillation image was formed in the plate. The image was reflected by a surface mirror set below the plastic scintillator plate and detected by a cooled charge coupled device (CCD) camera from the side. We changed the depths of the water in the phantom, obtained the scintillation images, and calculated a 3D scintillation image using the measured images. Measurements were made for 9 MeV and 12 MeV electron-beams using the imaging system. From the images, we could successfully form 3D scintillation images. The depth profiles measured from the 3D images showed almost identical distribution with those calculated by the planning system within the difference of 5%. The lateral profiles also showed almost identical within the difference of the widths less than 2.5 mm. We conclude that the proposed method is promising for 3D dose distribution measurements of electron-beams. [ABSTRACT FROM AUTHOR]

Abstract In this work patterning method of organic-inorganic hybrid methyl ammonium lead iodide (CH 3 NH 3 PbI 3) perovskite films is demonstrated. It was estimated that using focused E-beam make possible to etch the perovskite film. Etching took place due to formation of lead-organic volatile compounds. The etching process was strongly depended on grazing angle of incident beam. It was estimated that etching effectively take place when grazing angle was close to 45 °C. Next key factor was an accelerating voltage. Structure changes take place when E-beam accelerating voltage exceeds 1 kV. Change of structure was tracked by X-ray diffractometry and X-ray photoelectron spectroscopy analyses. The surface evaluation was monitored by atomic force microscopy and scanning electron microscopy methods. Bulk composition was estimated by energy dispersive spectrometer. [ABSTRACT FROM AUTHOR]

Polylactide (PLA) is presently the most studied bioderived polymer because, in addition to its established position as a material for biomedical applications, it can replace mass production plastics from petroleum. However, some drawbacks of polylactide such as insufficient mechanical properties at a higher temperature and poor shape stability have to be overcome. One of the methods of mechanical and thermal properties modification is crosslinking which can be achieved by different approaches, both at the stage of PLA-based materials synthesis and by physical modification of neat polylactide. This review covers PLA crosslinking by applying different types of irradiation, i.e., high energy electron beam or gamma irradiation and UV light which enables curing at mild conditions. In the last section, selected examples of biomedical applications as well as applications for packaging and daily-use items are presented in order to visualize how a variety of materials can be obtained using specific methods.

This project was carried out to study the effect of five different doses of electron-beam irradiation, including: 0 as control, 1.5, 3.5, 5.5 and 7.5 kGy on peroxidase (POD), superoxide dismutase (SOD) and polyphenol oxidase (PPO) activities of brown button mushroom (Agaricus brunnescens). The experiment was conducted using an electron beam accelerator (ESS-010-03) and measurements were made during 1, 4th, 8th, 12th and 16th day storage at 4 °C and 80 percent relative humidity. There was a significant difference between irradiated and non-irradiated (control) mushrooms in different enzymes (P≤0.01). Most Peroxidase activity was observed in mushrooms treated with 7.5 kGy. The irradiated mushroom with 7.5 kGy also showed the highest SOD activity. The lowest SOD activity in mushrooms was related to control in all days of storage. The mushrooms irradiated with 0 and 7.5 kGy contained higher and lower PPO activity using pyrocatechol as substrate respectively, during 12th and 16th day compared with other doses. Treatment of 0 kGy induced the highest PPO activity using pyrogallol as substrate in storage days. The data increased the current understanding of the effects of electron-beam irradiation on the enzyme activity changes associated with postharvest senescence and should lead to more targeted strategies for reducing postharvest quality loss in A. brunnescens. [ABSTRACT FROM AUTHOR]

Botryococcus sp. is an economically important microalgae as it contains carbohydrates, lipids, proteins, and a number of phytochemicals. The high concentrations of saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) in this strain also a valuable source for production of biofuel. Mutagenic engineering using irradiation has been known to increase the content of these biomass. The aim of this study is to know the effect of electron-beam irradiation to the growth profile and fatty acid composition of Botryococcus sp. In this study, Botryococcus sp. adjusted an optical density 1.0 after being exposed to different doses of electron-beam irradiation (160 kGy, 240 kGy, and 320 kGy) and induced random mutagenesis for strain improvement was observed based on high energy (1.5 MeV and 2 mA). Several mutants obtained were designated as strain B160, B240, and B320, respectively. The profile growth was significantly different between control (0 kGy) and irradiated microalgae strain. The highest growth is found in B320 mutant. Fatty acid of Botryococcus sp. control produced 7 fatty acids, B160 produced 7 fatty acids, B240 produced 6 fatty acids, whereas B320 produced 9 fatty acids. B320 produced hydrocarbon and phtalic acid as well as fatty acids. Total SFAs and MUFAs of B240 was increased 1.6 times compared to the wild type. The results would give some implications to improve the quality of biodiesel from Botryococcus sp. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate(PET) is difficult to be irradiation cross-linked at low dose for the aromatic groups. In this paper, trimethylolpropane triacrylate (TMPTA) was incorporated in PET fibers to sensitize the cross-linking. Changes in PET fibers subjected to electron beam irradiation at dose up to 200 kGy and dose rate 12 kGy/s were investigated by gel content, scanning electron microscopy, differential scanning calorimetry, X-ray diffraction, thermal gravimetric analysis and X-ray photoelectron spectroscopy. The gel content was 0.14% at dose of 60 kGy and it arrived at the maximum value 0.53% at 100 kGy. Irradiated fibers showed a decrease in the breaking strength and an increase in the elongation at break. The crystal form of PET fibers had not been changed and crystallinity decreased 28% with the increasing dose. The melting temperature shifted from the original 254.28 °C to 253.44 °C. The thermal stability and the amount of non-volatile residue at 800 °C increased at dose of 100 kGy. XPS analysis indicated that the number of C-C band increased to prove the occurring of cross-link. The surface of PET fibers got rougher after irradiation and the anti-dripping property had not been improved effectively for the low degree of cross-linking. [ABSTRACT FROM AUTHOR]

Owing to the overall increase in herbal infusions’ consumption, there’s a progressively higher need of suitable plant material, as well as adequate conservation techniques to maintain its quality. Among, the available technologies, irradiation is gaining interest as a feasible preservation method. In line with this approach, this wok was designed to evaluate the effects of electron-beam and gamma irradiation over the phenolic profiles of two plant species Melissa officinalis L. (LB) and Melittis melissophyllum L. (BB). Individual phenolics were characterized by high-performance liquid chromatography coupled to a diode array detector and a mass spectrometer (HPLC-DAD-ESI/MS). Irradiated samples showed a general increase in individual phenolic contents, especially in lithospermic acid A in LB and 5- O -caffeoylquinic acid in BB. Thus, this study revealed the potential usefulness of both conservation technologies when employed to this type of plants. [ABSTRACT FROM AUTHOR]

Biofouling is still a major challenge in membrane science and accounts for up to 70% of the total costs of membrane-operated filtration systems. Thus, in this work, a thin layer of diverse synthetic hydrogels has been applied via electron beam-initiated polymerization on a polyethylene terephthalate (PET) track-etched membrane (fundamental study) as a simple model membrane and on a conventional used polyethersulfone (PES) ultrafiltration membrane (applied study) to study its anti-biofouling properties. The effect of hydrophilicity, roughness, surface charge, and degree of swelling of the attached hydrogel on algae (Chlorella Vulgaris) fouling was studied in a fundamental way, and long-time tests in a membrane bioreactor (MBR, filtration area 1.5 m2) over 11 months were performed on an applied scale. The hydrophilicity, roughness, and surface charge had only a minor to no effect on algae fouling. Only the degree of swelling had an impact on biofouling. The membranes with hydrogels with a low degree of swelling (6%) showed a lower loss of permeability (only 5%) after fouling, compared to a 25% loss with the highest degree of swelling (25%). During the operation over 11 months in a membrane bioreactor (MBR), the permeability is higher (ca. 10%) in a module equipped with hydrogel modified membranes, compared to a module with reference membranes. Thus, modification of membranes with a thin layer of a hydrogel results in an anti-biofouling surface. The degree of swelling is a decisive parameter to control biofouling. [Display omitted] • Electron beam polymerization of synthetic hydrogels on polymer membranes. • Charge and roughness had only a minor or no influence on anti-biofouling behavior. • Only hydrophilicity and degree of swelling showed an impact on biofouling behavior. • PEGDA hydrogel layer improved permeability of a MBR over 11 months of operation. [ABSTRACT FROM AUTHOR]

Optical beam has been the veteran inspector of semiconductor wafer production house, ever since the birth of integrated circuit (IC). As technology and market place raise the bar on chip density, Moore’s law stretches to the limit. Due to its inherent physical limitations, the optical method just cannot see the measuring rod of silicon industry getting recalibrated to finer nano-scales. Electron Beam Inspection (EBI), by virtue of its high resolution, has started to rule the nodes at 10 nm and below. As the geometries shrink, defects can reside deep within the structures. EBI can find those tiny defects, which otherwise go scot-free with optical tools. However, EBI suffers the handicap of poor performance and low throughput. It is therefore essential to complement EBI by judiciously crafting out the methods for getting the desired performance, a subject matter to which, this article is committed to. The research torchlights the critical EBI throughput problem to round-up “care-areas”. Such guided and focused inspection augments throughput, thereby positioning EBI as the industrial grade candidate in finer nanometer segment. Besides gearing up to current trends, the smart EBI school of thought is inspirational, to fuel the aspirations for 1 nanometer scale. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the physicochemical and textural properties of heat-induced gels prepared with pork muscles irradiated with gamma rays, electron beams, and X-rays. Pork muscles were irradiated at 5 kGy using the different irradiation sources, and heat-induced gels were prepared from the irradiated pork muscles at a protein concentration of 5 mg/mL. Each irradiation treatment produced lower water-holding capacity, protein solubility, apparent viscosity, hardness, springiness, cohesiveness, gumminess, and chewiness than the control gel prepared with non-irradiated pork muscle ( P < 0.05). In addition, gamma irradiation was more influential than electron or X-ray irradiation on the negative impacts on water-holding capacity and texture of heat-induced gels. Therefore, this study suggests that the irradiation source could be one of the significant factors affecting gelling properties of irradiated meat. [ABSTRACT FROM AUTHOR]

The interest in diamond like carbon (DLC) coatings and their modification for biomedical applications is strongly increasing during the last years. Improvement of surface resistance to scratching and biocompatibility are the main goals of recent developments. Moreover, different capabilities of adjacent areas on surfaces are often required by complex applications. In this study, different deposition methods for diamond-like carbon (DLC) coatings were compared for their suitability in biomedical applications. In addition, DLC coatings modified by non-thermal electron-beams were investigated with regard to their biological interactions. The DLC coatings were deposited using four different methods (plasma-activated chemical vapor deposition, physical vapor deposition by magnetron sputtering, and physical vapor deposition via cathodic arc – both unfiltered and filtered). The different DLC coatings were characterized with regard to their wettability, morphology, roughness, and coating adhesion. The ability of coatings to withstand repeated sterilization cycles was investigated using a specialized test protocol parallel to standard sterilization procedures for medical devices. Biological evaluation was performed using human fibroblasts by assessing metabolic activity and cell counts. Electron-beam modification of the coatings was performed under ambient conditions using a low-energy electron-beam facility (150 kV acceleration voltage). All DLC coatings investigated were found to be biocompatible, with the coating deposited by magnetron sputtering showing the best results. In general, electron-beam modification resulted in the hydrophilicity of the different DLC coatings increasing, but no changes in surface morphology or roughness were observed. The cell adhesion to electron-beam-modified DLC coatings was reduced to 30% of the untreated DLC coatings, what can be attributed to changes in the surface chemistry. The long-term stability of the modified DLC coatings was also confirmed. Therefore, electron-beam treatment represents a promising tool for modifying and functionalizing DLC coatings, especially if varying requirements concerning biomedical functionality and cell adhesion are involved. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electron-beam irradiation up to 100 kGy has an insignificant on chemical structure of poly(HEMA). • Intrinsic viscosity measurements and size exclusion chromatography confirmed the propensity to undergo chain scission. • The radiation sensitivity of poly(HEMA) is thought to be due to the limited ester side chain mobility hindering radical recombination as well as hydrogen bonding. • Acetaldehyde and carboxyl compounds were identified as the main products of polymer radiolysis. The understanding of the radiation-induced degradation mechanisms of polymers is essential towards developing new application implying radiation technology. This study reports on the effect of electron-beam (EB) radiation on linear poly(2-hydroxyethyl methacrylate) upon exposure to 5–100 kGy doses. Various spectroscopic and analytic methods were used to monitor the effects of EB radiation to assess poly(HEMA) reactivity during irradiation in the solid amorphous state. Intrinsic viscosity measurements and molecular weight (MW) determination using size exclusion chromatography (SEC) confirmed the propensity to undergo chain scission. The radiolytic yields for cross-linking and scission were assessed. Spectroscopic data allow to propose a reasonable mechanism accounting for these observations. [ABSTRACT FROM AUTHOR]

PtRu/C electrocatalysts (carbon-supported PtRu nanoparticles) were prepared submitting water/ethylene glycol mixtures containing Pt(IV) and Ru(III) ions and the carbon support to electron beam irradiation. The electrocatalysts were characterized by energy dispersive X ray analysis (EDX), X ray diffraction (XRD) and cyclic voltammetry and tested for methanol electro-oxidation aiming fuel cell application. The obtained PtRu/C electrocatalysts showed superior performance for methanol electro-oxidation at room temperature compared to commercial PtRu/C electrocatalyst.

The effect of irradiation source (gamma-ray, electron-beam, and X-ray) and dose levels on the physicochemical, organoleptic and microbial properties of cooked beef patties and pork sausages was studied, during 10 days of storage at 30±1 °C. The processed meat products were irradiated at 0, 2.5, 5, 7.5, and 10 kGy by three different irradiation sources. The pH of cooked beef patties and pork sausages was unaffected by irradiation sources or their doses. The redness of beef patties linearly decreased with increasing dose level ( P <0.05), obviously by e-beam irradiation compared to gamma-ray and X-ray ( P <0.05). The redness of pork sausages was increased by gamma-ray irradiation, whereas it decreased by e-beam irradiation depending on absorbed dose level. No significant changes in overall acceptability were observed for pork sausages regardless of irradiation source ( P >0.05), while gamma-ray irradiated beef patties showed significantly decreased overall acceptability in a dose-dependent manner ( P <0.05). Lipid oxidation of samples was accelerated by irradiation depending on irradiation sources and dose levels during storage at 30 °C. E-beam reduced total aerobic bacteria of beef patties more effectively, while gamma-ray considerably decreased microbes in pork sausages as irradiation dose increased. The results of this study indicate that quality attributes of meat products, in particular color, lipid oxidation, and microbial properties are significantly influenced by the irradiation sources. [ABSTRACT FROM AUTHOR]

We have demonstrated nanomechanical applications using physicochemical and electrochemical phenomena of inverted-electron beam lithography (I-EBL), which induced in-situ two-dimensional (2-D) processing on wet samples and a living cell after the EB was stoppted in a 100-nm thick SiN membrane. The incident EB generates a virtual electrode and then this induces electrochemical and electrokinetic phenomena around the scanning trajectory. The I-EBL processing has a 120-nm resolution in full-width-at-half-maximum (FWHM) at the deposited line-and-space pattern in 10 mM 3,4-ethylenedioxythiophene (EDOT) diluted water solution. The virtual electrode also causes a electrokinetic local repulsive force with < ∼ 1 μm resolution toward the negatively charged nanoparticles, and the 2-D scanning of the EB allows 2-D actuation of the nanoparticles dispersed in a pure water solution. The virtual electrode also induces local detachment of adherent nanoparticles and focal adhesion of a living cell from the SiN membrane in a saline solution, probably due to both electrokinetic and partly chemical protein denaturation processes. The local detachment of a living cell is utilized to investigate spatio-temporal distributions of intracellular elastic strain as mechanical strain microscopy (MSM), which represents mechanical connectivity in the intracellular structure. This MSM should provide visualization of the location of the force generation in the cell. [ABSTRACT FROM AUTHOR]

The safety of microwave and electron-beam treatments has been demonstrated, in regards to the formation of reaction products that could endanger human health. An integrated approach was used combining the potential toxicity of all the substances likely to migrate to their chemical characterizations. This approach was applied to polypropylene (PP) films prepared with a selection of additives. Components were identified by liquid and gas chromatography using a mass selective detector system. Their potential toxicity was assessed using three in vitro short-term bioassays and their migrations were carried out using a standards-based approach. After the electron-beam treatment some additives decomposed and there was a significant increase in the polyolefin oligomeric saturated hydrocarbons concentration. PP prepared with Irgafos 168 led to a significantly strong cytotoxic effect and PP prepared with Irganox 1076 induced a dose-dependant estrogenic effect in vitro . Migration values were low and below the detection limit of the analytical method applied. [ABSTRACT FROM AUTHOR]

Effects of low-dosage electron beam irradiation on antioxidant activities of Navel oranges during storage at a low temperature of 3°C were studied. Oranges were irradiated at dosages of 0.2, 0.4, 0.6, 0.8, and 1.0 kGy and changes in antioxidant compounds and antioxidant activities were investigated. No changes in total phenolic contents or flavonoid contents were observed with an increase in radiation dosage. Also, no differences between non-irradiated and irradiated oranges in DPPH radical scavenging and ABTS radical scavenging activities, FRAP values, and reducing powers were observed. Electron beam irradiation at dosages less than 1 kGy does not affect levels of antioxidant compounds and antioxidant activities of Navel oranges. [ABSTRACT FROM AUTHOR]

The International Atomic Energy Agency (IAEA) has launched the NUTEC Plastics initiative (NUclear TEchnology for Controlling Plastic Pollution), to mitigate plastic pollution, covering two areas: monitoring and impact assessment of microplastic in marine environments and addressing innovation in the treatment of plastic waste using radiation technologies. The latter approach is presented here, with a focus on the application of radiation-driven processes in the sorting, compatibilization, degradation, and thermal conversion of plastic waste and the main priorities for current projects. Keeping in mind the economic implementation of these approaches for the recycling of plastic waste, the latest trends in the development of powerful electron accelerators are presented and evaluated. Among the most promising application areas are irradiation methods for large-scale immobilization of plastic waste into road and building materials, combining virgin plastics with post-consumer plastics, and thermo-radiolysis, i.e. simultaneous irradiation and heating for synergistic decomposition of macromolecules/polymers. • The recycling of plastics can be enhanced by implementation of radiation technologies. • Radiolysis increases the compatibility of plastics with building materials components. • The difference in the lifetimes of radiolytic intermediates can be exploited for the sorting of polyolefins. • Radiolytic degradation can enhance the pyrolytic conversion of plastics. [ABSTRACT FROM AUTHOR]

Highlights: [•] We examine changes in HDPE properties when waste and clay are used as reinforcement. [•] The addition of only 3% of clay leads to important gains in HDPE properties. [•] The use of electron-beam contributes to greater improvements in material properties. [•] We observe 85% of cross-linking degree for the HDPE when treated with e-beam. [ABSTRACT FROM AUTHOR]

Mushrooms are very perishable foods due to their high susceptibility to moisture loss, changes in color and texture, or microbiological spoilage. Drying is considered as the most appropriate method to prevent these alterations, but it has some limitations, such as shrinkage, enzymatic and non-enzymatic browning reactions, and oxidation of lipids and vitamins. According to previous studies, irradiation might effectively attenuate the undesirable changes caused by drying process, ensuring also higher shelf-life of mushrooms and their decontamination. Electron-beam irradiation presents some technological advantages, since it allows higher dose rates and the possibility to be used in most foods/or thin products in a short period. Herein, the combined effects of electron-beam irradiation (0, 0.5, 1 and 6 kGy) and storage time (0, 6 and 12 months) were evaluated by measuring changes in nutritional parameters, namely, free sugars, tocopherols, fatty acids and antioxidant activity. As indicated by linear discriminant analysis, storage time had a higher effect on all the evaluated parameters, except fatty acids, which suffer significant changes with both factors. Overall, the obtained results indicate that electron-beam irradiation might be considered as a suitable technique, allowing long-lasting conservation periods while reducing changes induced by drying treatment. [ABSTRACT FROM AUTHOR]

Abstract: Mushrooms are highly perishable matrices and to extend time of consumption they need to be preserved. Since all the available conservation technologies present disadvantages, the combination of two different processes might minimize some of the limitations. Therefore, in the present work, electron-beam irradiation (up to 10kGy) was applied to dried samples of Boletus edulis and Russula delica, extending previous findings using gamma- and electron-beam irradiations at lower doses (up to 6kGy) and different wild mushroom species. The effects on nutritional, chemical and antioxidant parameters were evaluated. In general, the applied irradiation, particularly at higher doses, had significant effects on chemical profiles (protein, sugar and organic acid levels tended to decrease, while unsaturated fatty acids, tocopherols and phenolic acids presented higher levels in irradiated samples) and antioxidant activity (increased in irradiated samples). Nevertheless, the assayed doses might be considered to enhance the conservation of B. edulis, allowing the simultaneous achievement of disinfestation and decontamination effects. Industrial relevance: B. edulis is among the most commercialized mushrooms worldwide. However, as all mushrooms, suffers severe conservation problems. Electron-beam irradiation (specifically at 6kGy) proved to be a suitable technology for mushrooms conservation, since it allows disinfestation and decontamination processes without causing high changes in the chemical profiles. In R. delica case, differences caused by irradiation were higher, but it was also found that applying 6kGy had the same effects of 2kGy dose, which might be useful for disinfestation (insects elimination) and decontamination (elimination of bacteria and other microorganisms) purposes. [Copyright &y& Elsevier]

Abstract: Surface layers containing ~1.57–2.55% (wt) carbon were produced by atmospheric electron-beam cladding of low carbon steel plates with an iron–graphite powder mixture. The main process parameter determining the thickness, structure, and mechanical properties of the hardened layer was the electron-beam current. As the beam current was increased from 20 to 26mA, the thickness of the cladding layers increased from 1.2 to 2.6mm and the hardness decreased from 5.7 to 4.5GPa. In friction tests against fixed abrasive particles, the wear-resistance of the cladding layers was close to the wear resistance of pack-carburized specimens. In electron-beam cladding of steel plates 10mm thick with the powder mixture with electron-beam scanning over the plate surface, the cooling rate of the surface layer was less than the critical value, which made it impossible to obtain a martensitic structure. The main structural components in the cladding layers were ledeburite, secondary Widmanstätten cementite, and pearlite. To produce a high-carbon martensitic structure directly during cladding by enhancing the heat transfer to the colder volume of the workpiece, it is necessary to increase the thickness and mass of the workpiece or reduce the thickness of the hardened layer. Saturation with carbon and quenching of the cladding layer can be performed successively using the same electron accelerator. [Copyright &y& Elsevier]

Abstract: This study focuses on the development of novel biocompatible macroporous cryogels by electron-beam assisted free-radical crosslinking reaction of polymerizable dextran and hyaluronan derivatives. As a main advantage this straightforward approach provides highly pure materials of high porosity without using additional crosslinkers or initiators. The cryogels were characterized with regard to their morphology and their basic properties including thermal and mechanical characteristics, and swellability. It was found that the applied irradiation dose and the chemical composition strongly influence the material properties of the resulting cryogels. Preliminary cytotoxicity tests illustrate the excellent in vitro-cytocompatibility of the fabricated cryogels making them especially attractive as matrices in tissue regeneration procedures. [Copyright &y& Elsevier]

Abstract: It has been known that a good quality h-BN layer can only be grown within a narrow temperature window of 1020–1100 K on a copper substrate. We found that the growth temperature window on Cu(111) surface could be lowered up to 100 K by ionizing and/or exciting borazine precursor gas with an electron-beam. The structures of a hexagonal boron nitride (h-BN) layers grown at various substrate temperatures on a Cu(111) were examined using scanning tunneling microscopy. We found that the grown h-BN film exhibits highly inert behavior with wide bandgap semiconductor characteristics. [Copyright &y& Elsevier]

In this work, the properties of electron-beam irradiated low density polyethylene (LDPE), ethylene vinyl acetate (EVA) and blends were investigated. EVA addition had an enhancement effect on crosslinking of irradiated LDPE/EVA blends. The measured gel content increase of the blends and the improvement of thermal elongation, tensile strength, elongation at break, thermal aging and heat deformation, have confirmed the positive effects of electron-beam irradiation on the blend properties. The crystallinity of the blends decreased with irradiation. The gel content and hot set tests showed that the degree of crosslinking in the amorphous regions was dependent on the dose and blend composition. Increasing the EVA content resulted in tighter network structures. A significant improvement in the tensile strength of the neat EVA samples was obtained upon electron-beam irradiation up to 210 kGy. The irradiated LDPE/EVA blends showed improved tensile strength and elongation at break, when compared to LDPE. The enhanced irradiation crosslinking of the LDPE/EVA blends was proportional to the good compatibility and the increasing degree of the amorphous region's content of the LDPE/EVA blends. The possible degradation mechanism of LDPE/EVA blends was discussed quantitatively with a novel method step analysis process of irradiated LDPE/EVA blends in the thermal gravimetric analysis (TGA) technique. It was found, with measuring thermal conductivity (k) and specific heat capacity (Cp) of the blends, that the k values of the LDPE samples at a prescribed temperature range decreased with increasing irradiation. An increase in the crystallinity led to an increase in the k values and a decrease in the Cp values of the LDPE samples. Irradiation below 150 kGy decreased the Cp (at 40°C) and k in average values, whereas increasing the EVA made enhanced the Cp and k values of LDPE/EVA blends at each irradiation. The surface resistance and volume resistivity (VR) of the blends reached a maximum at a 170 kGy irradiation and 30 wt% of EVA. Increasing the amount of EVA contents resulted in enhancement of the dielectric loss factor for the irradiated blends. [ABSTRACT FROM AUTHOR]

Irradiation crosslinking of PA6 fibers with and without the presence of triallyl cyanurate (TAC) was investigated. The dose for incipient gel formation was 500 kGy for pristine PA6 fibers and it decreased to 12 kGy when 5 % TAC was incorporated. Changes in structure and properties of irradiated PA6 fibers were analyzed by X-ray diffraction, infrared spectroscopy and thermal gravimetric analysis. Irradiation crosslinking improved the anti-dripping properties of PA6 fibers effectively. Irradiated samples showed an increase of the breaking strength and then a decrease at further doses due to radiolysis effect, the elongation at break decreased during the irradiation process. Irradiation crosslinking had not changed the crystal form and crystallinity decreased first and then increased to some extent. DSC measurement reported that the melting temperature decreased with increasing the dose. The thermal stability decreased after irradiation whereas the amount of nonvolatile residue at 600 °C increased as the irradiation dosage increased. The infrared spectra of irradiated samples were identical with the unirradiated, no new bands were observed.XPS analysis showed that the number of C-C band increased after irradiation which proves that branching and crosslinking has occurred. [ABSTRACT FROM AUTHOR]

Abstract: The short shelf-life of mushrooms is an obstacle to the distribution and marketing of the fresh product. Thus, prolonging postharvest storage, while preserving their quality, would benefit the mushroom industry as well as consumers. There has been extensive research on finding the most appropriate technology for mushrooms preservation. Gamma, electron-beam and UV irradiation have been shown to be potential tools in extending the postharvest shelf-life of fresh mushrooms. Studies evaluating the effects of ionizing radiation are available mainly in cultivated species such as Agaricus bisporus, Lentinus edodes and Pleurotus ostreatus. This review comprises a comprehensive study of the effects of irradiation on physico-chemical parameters (weight, colour, texture and pH), chemical compounds including nutrients (proteins, sugars and vitamins) and non-nutrients (phenolics, flavonoids and flavour compounds), and on biochemical parameters such as enzymatic activity of mushrooms for different species and from different regions of the world. [Copyright &y& Elsevier]

The history and modern state of the development of electron-beam accelerators at the Skobeltsyn Institute of Nuclear Physics at Moscow State University and investigations with their use are considered. [ABSTRACT FROM AUTHOR]

Abstract: Plasma generated by non-polymerizing gases (oxygen, air and nitrogen) and electron-beam irradiation under different atmospheres were studied as possible pretreatments to an enzymatic process with transglutaminase (TGase). The aim was to improve the accessibility of target groups of TGase present in wool fabrics to the enzyme, thanks to chemical etching or the removal of the epicuticle layer by physical etching, thus leading to increased formation of cross-links or incorporation of primary amine compounds. For the plasma treatment, we found that oxygen promotes the cleavage of disulphide bonds by oxidation of sulphur species: a reduction of oxygen content in the gas plasma induced a reduction in oxidation yield, as shown by FTIR measurements. Conversely, nitrogen promoted a chemical etching reaction. The most significant effects were observed at high treatment power (400W), where both cleavage of polymer chains and removal of the epicuticle layer were promoted. Air plasma at high power was the most promising pretreatment to the enzymatic process. The modifications induced a good penetration of the enzyme into the fibre core and no significant changes in enzyme activity were observed in contact with the plasma-treated fabrics. In contrast, by increasing the energy of the electrons in E-beam treatments no significant superficial modifications were observed. In fact, they promoted the cleavage of high-energy bond, such as S–S linkage, by enhancing depolymerization reaction. [Copyright &y& Elsevier]

This study was performed to verify the feasibility of 7.5 MeV X-rays for food pasteurization through a comparison of the bactericidal efficiency with those of other sources for selected bacterial pathogens. No significant differences were observed between the overall bactericidal efficiency for beef-inoculated pathogens based on the uncertainty of the absorbed dose and variations in bacterial counts. This result supported that all three irradiation sources were effective for inactivation of food-borne bacteria and that 7.5 MeV X-rays may be used for food pasteurization. [ABSTRACT FROM AUTHOR]

The final aperture superposition technique (FAST) is a method to reproduce rapidly the electron-beam depth dose curves and output factors that would be calculated by a full Monte Carlo simulation. FAST uses precalculated Monte Carlo-based differential dose arrays and performs a superposition of open and shielded contributions to account for arbitrarily shaped insert openings. The objective of this work was to refine and validate the accuracy of the FAST method for a full range of treatment parameters. Compared to full simulations, raw FAST calculations tended to underestimate dose near the surface deposited by particles that crossed the shield-opening interface of the insert. In this study, a set of empirical correction curves was derived to reduce the errors from this “collimator effect.” FAST and full simulation calculations were compared for every combination of six beam energies (6–21 MeV), four applicator sizes (10–25 cm), and two source-to-surface distances (SSDs) (100 and 110 cm). Validation tests were performed for a total of 192 fields using four sample insert openings: an open insert and 2, 3, and 5 cm diameter circular openings. Calculations were also performed for four patient inserts with irregularly shaped openings. Using the empirical correction curves, systematic errors were reduced, resulting in mean dose differences of less than 1% of the maximum full simulation dose. FAST relative output factors reproduced full simulation output factors to within 3% for all configurations except for the 2 and 3 cm diameter openings for the 6 and 9 MeV beams at 110 cm SSD. The maximum shift between the FAST and full simulation depth dose curves in the 90%–80% fall-off region was less than 3 mm for 97% of the fields. For the patient insert calculations, differences in output factors and mean differences in depth dose curves were within 1.5% with maximum shifts of 1.5 mm in the 90%–80% fall-off region. A small set measurements also demonstrated 3% accuracy in FAST output factors except for a 5% deviation for a 2 cm diameter insert for the 6 MeV beam at 110 cm SSD. These results demonstrate that FAST can be used to provide output factors and depth dose curves for most clinical cases. [ABSTRACT FROM AUTHOR]

The phase composition and defect substructure of the pearlite steel (0.65%C, <1%Mn) layers with liquid and solid phase transformation subjected to pulse low-energy high-current electron beam processing have been investigated by means of transmission electron microscopy. The electron beam effect is expressed in the defect substructure change of the ferrite interlayers and in the amplitude increase of the far acting stress fields in the zone of thermal action. Different stages of polymorphous α→γα transformation have been analyzed in a solid-phase transformation zone. The reasons for the formation of two-dimensional classes of a-phase grains with varying matrensite phase morphology in the liquid phase transformation zone are discussed. [ABSTRACT FROM AUTHOR]

Abstract: The spent electron beam of megawatt-class CW gyrotrons requires magnetic sweeping to keep the specific heat dissipation on the collector surface within technically acceptable limits of about 500W per cm2. Conventionally this is realised with a solenoid coil placed over the collector, which sweeps the strike point of the electron beam up and down the collector-wall at low frequency (<10Hz). The low frequency is necessitated by the strong screening effects due to eddy-currents in the copper-collector-wall. This paper describes the realisation and test results obtained with a six-coil 50Hz transverse field sweep system (TFSS) on the 140GHz 1MW CW prototype gyrotron for W7-X. The advantages of this system compared to the conventional scheme are discussed and an outlook on further enhancements is given. [Copyright &y& Elsevier]

Abstract: Moore’s law continues to prescribe ever smaller device dimensions with each new device node. While the new device nodes are scheduled at even pace, the innovation required to obtain commensurate device performance is greater with every device node. This increased complexity in the process, while maintaining the momentum of Moore’s law, is increasing the pressure on the development teams to increase the learning rate on new processes and their interactions. There have been many publications on mix-and-match lithography to enable early learning. In this technique, one whole device level (often the gate definition) is replaced by a different technology (often e-beam), while all the other levels continue to be patterned using traditional optical lithography. Hybrid lithography, by contrast, is the use of different lithography technologies on a single resist level which enables the marriage of both technology’s best properties. In this work, we present hybrid e-beam direct write and optical lithography, enabling high throughput (optical), high-resolution (EBDW), excellent overlay (EBDW) and fast prototyping (EBDW). We will show how IBM has used hybrid lithography to enable early learning on back end of the line (BEOL) processes and on extremely scaled SRAM cells (0.143μm2) [D.M. Fried, et al., IEDM Proceedings (2004) 261–264]. [Copyright &y& Elsevier]