Impact Of Electron Beam Irradiation Research Articles

Cytotoxicity and antioxidant activity of iron oxide nanopowders synthesized by radiation-chemical method using different precursors

The study revealed a correlation between the cytotoxicity and antioxidant activity of iron oxide nanopowders produced by the radiation-chemical method and the choice of precursors (iron (III) nitrate or iron(II) sulfate), and the temperature of pre-annealing of the synthesized product, and also irradiation with accelerated electrons. Notably, high and lowabnormal cytotoxicity of aqueous suspensions of samples S300 and S400, respectively, annealed at temperatures of 300 and 400 °C, was observed for the first time at all concentrations (0.1–1.0 ml/mg). The likely cause of this abnormal cytotoxicity was identified as alterations in the textural and structural properties of NP after annealing.Furthermore, a significant impact of electron beam irradiation on the antibacterial and antioxidant properties of both unannealed and annealed iron oxide NP was discovered with irradiated samples exhibited lower cytotoxicity compared to non-irradiated ones. Additionally, the deposition of nanosilver on the surface of iron oxide powders was found to significantly influence their biological properties, with the survival of Vero cell cultures being dependent on the composite concentration in the aqueous suspension.A study of the oxidative stress of composites based on iron oxides coated with silver showed that they significantly increased cell viability, and at a concentration of 1 mg/ml provided complete mitigation of oxidative stress in cells.

Investigating the impact of electron beam irradiation on electrical, magnetic, and optical properties of XLPE/Co3O4 nanocomposites

Nowadays, many researchers aim to fill polymer materials with inorganic nanoparticles to enhance the polymer properties and gain the merits of the polymeric host matrix. Sol–gel synthesized Co3O4 nanoparticles are subjected to different doses of electron beam (10, 20, and 30 kGy) to study their physiochemical properties and choose the optimized nanoparticles to fill our polymeric matrix. Crosslinked polyethylene (XLPE) has been filled with 5 wt % of un-irradiated cobalt oxide nanoparticles using the melt extruder method. The structural, optical, magnetic, and electrical properties of the XLPE/Co3O4 nanocomposite before and after exposure to different doses of electron beam radiation have been characterized. The crystallite size of face-centered cubic spinel Co3O4 nanoparticles has been confirmed by XRD whereas and their unique truncated octahedral shape obviously appears in SEM micrographs. The crystallite size of Co3O4 nanoparticles has decreased from 47.5 to 31.5 nm upon irradiation at a dose of 30 kGy, and significantly decreased to 18.5 nm upon filling inside XLPE matrix. Related to the oxidation effect of the electron beam, the Co2+/Co3+ ratio on the surface of Co3O4 nanoparticles has decreased upon irradiation as verified by XPS technique. This consequently caused the partial elimination of oxygen vacancies, mainly responsible for the weak ferromagnetic behavior of Co3O4 in its nanoscale. This appears as decreased saturation magnetization as depicted by VSM. The XLPE/Co3O4 nanocomposite has also shown weak ferromagnetic behavior but the coercive field (Hc) has increased from 112.57 to 175.72 G upon filling inside XLPE matrix and decreased to 135.18 G after irradiating the nanocomposite at a dose of 30 kGy. The ionic conductivity of XLPE has increased from 0.133 × 10–7 to 2.198 × 10–3 S/cm upon filling with Co3O4 nanoparticles while a slight increase is observed upon irradiation.

Effects of electron beam irradiation on protein oxidation and textural properties of shrimp (Litopenaeus vannamei) during refrigerated storage

Protein oxidation leads to changes in shrimp texture, which affects sensory profile and consumer acceptability. This study aimed to evaluate the impact of electron beam irradiation (EBI) on protein oxidation and textural properties of Litopenaeus vannamei during refrigerated storage. Results revealed that EBI treatment and storage increased the protein oxidation level of shrimps. Shrimps irradiated with ≥ 7 kGy exhibited remarkably higher (P < 0.05) reactive oxygen species, turbidity, and carbonyl contents, and remarkably lower (P < 0.05) Ca2+-ATPase activity, surface hydrophobicity, solubility, and total sulfhydryl contents compared to the control group (0 kGy) on the 7th day of storage. Shrimps irradiated with 3 and 5 kGy exhibited remarkably higher (P < 0.05) hardness, springiness, and chewiness compared to the control group (14.99 N, 1.26 mm, and 3.19 mJ). Collectively, suitable EBI doses of 3–5 kGy were recommended in shrimp preservation to inhibit texture softening by inducing moderate protein oxidation.

The impact of electron beam irradiation on some novel borate glasses doped V2O5; Optical, physical and spectral investigation

New borate glass systems with composition of 56B2O3 + 25Li2O + 10Na2O + 5CaO + 2SrO + 2Al2O3 + 0.5 TeO2 + x V2O5, where × = 0.2 or 0.3 (wt. %), were fabricated via the traditional melting-annealing method at low temperature (650–750 °C). Some of the glasses optical, physical, chemical and spectral measurements were investigated within the impact of electron beam (EB) irradiation up to 8 kGy. UV–visible spectra revealed peaks at ∼ 290 and ∼ 300 nm for 0.2 and 0.3 V2O5 glasses, respectively. In addition to broad visible band at ∼ 580 nm owing to the participation of vanadium ions as V5+ with possible conversion to V3+/V4+ under the effect of EB irradiation. FTIR spectra revealed the main trigonal BO3 and tetrahedral BO4 units with an increase in N4 values by the progressive EB irradiation. ESR spectra revealed a gradual increase in intensity with irradiation doses. While, testing chemical durability in distilled H2O at 100 °C reveals a good manner before and after irradiation process. Some physical parameters e.g. optical energy gap (Eoptdirect and Eoptindirect), Urbach energy (EUrbach), refractive index (n) and spectral distribution (k) showed also a gradual decrease with continual irradiation owing to the gradual generating of non-bridging oxygens NBOs and progressive transformation of BO3 to BO4 units. The overall data displayed some dosimetric properties of the two studied glasses with a useful dose range 3–8 kGy of EB radiation. The study recommends usage of glasses as glass dosimeters in medical sterilization, industry and food irradiation processing.

Electron beam irradiation enhanced extraction and antioxidant activity of active compounds in green walnut husk

Green walnut husk (GWH) contains abundant active compounds and is valued as a potential source of natural antioxidants. This study aimed at assessing the impact of electron beam irradiation (EBI) pretreatment on the extraction yield and antioxidant activity of active compounds in GWH. The ultrasonic extraction of active substances was optimized by response surface method (RSM). Scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction revealed physical structure changes in GWH powder. After EBI pretreatment, the content of polyphenols, flavonoids, and triterpenes in GWH increased by 18.88%, 43.00%, and 11.08%, respectively. Irradiation doses up to 30 kGy, DPPH, OH, and ABTS radical scavenging activity and reducing power of the crude extract were enhanced by 9.56%, 15.62%, 15.60%, and 36.98%, respectively. This was significantly different (P < 0.05) than the non-irradiated GWH. Therefore, EBI is a new pretreatment technology with potential application in the extraction and utilization of GWH.

Impact of electron beam irradiation in potato starch films containing hibiscus aquous extract

The development of starch films containing natural antioxidants is one alternative of active packaging. Starch is a well-studied natural biopolymer that can be used for the development of biodegradable films because it presents a low cost, is easy to obtain and presents good ability to form films. Hibiscus sabdariffa, commonly known as hibiscus, roselle or red sorrel, is an annual herbaceous sub shrub that contains many types of biocompounds, including organic and phenolic acids. The aim of the present work was to determine the influence of electron beam irradiation on potato starch film containing hibiscus extract. The aqueous hibiscus solution was prepared by boiling for 3 min 1% w/ml dehydrated hibiscus flowers in 500 ml deionized water. The film forming solution was prepared by casting (5% potato starch, 3% glycerol as plasticizer and the hibiscus solution) and irradiated in a 1.5 MeV electron beam accelerator Dynamitron II (Radiation Dynamics Inc.), with doses of 0, 20, 40 and 60 kGy. After drying some mechanical properties were measured. The tensile strength of the control films and the irradiated ones was established. There were no significant differences among them. It looks like hibiscus antioxidants were able to prevent the expected starch radiation degradation process caused by radiation generated free radicals.

Toward recycling ʺunsortableʺ post-consumer WEEE stream: Characterization and impact of electron beam irradiation on mechanical properties

The work reported here is the first study aimed at providing a full screening of a real unsortable non-recycled post-consumer WEEE stream free of brominated flame retarded plastics, separated using on-line X-ray detection, toward its recycling. In the existing sorting lines, up to 40% of plastics from waste electrical and electronic equipment (WEEE) stream can be rejected, herein named unsortable plastics. To have the most representative homogeneous sample for physico-chemical characterizations, a sampling method was developed to overcome the heterogeneity of the investigated 500 kg batch. The batch screening on both representative samples (∼500 μm size) and 100 plastic fractions (∼20 mm size), by means of routine techniques used in the plastic industry, has allowed to quantify reliably the main polymers included in the studied batch; ∼50% styrene-based polymers, ∼15% polypropylene (PP), ∼15% polycarbonate (PC), ∼1–4% polyamide (PA), polyethylene (PE), polyvinyl chloride (PVC), poly (ethylene terephthalate) (PET), poly (methyl methacrylate) (PMMA) and ∼8% of multi-layer plastics, paints and thermosets. The identification of the ∼8.0% inorganic phase by X-ray fluorescence spectrometry revealed the presence of several additives/charges commonly incorporated in plastic materials, such as calcium carbonate and talc. The studied batch was then subjected to electron beam irradiation at 50 and 200 kGy doses, as a means of compatibilization between the batch components. The mechanical properties and thermal behavior of irradiated samples pointed out the crucial role of the residual free radical scavenger agents present in post-consumer WEEE streams, leading to significantly different properties compared to those of irradiated virgin polymer blends highlighted in the literature.

Impact of electron beam irradiation on the chlorophyll degradation and antioxidant capacity of mango fruit

At the present, the mechanism of chlorophyll degradation in response to ionizing irradiation in harvested fruits have not been examined. To understand the effect of electron beam (E-beam) irradiation on the chlorophyll degrading pathway in relation to chlorophyll degrading enzymes activity, reactive oxygen species (ROS) and antioxidant capacities of harvested mangoes stored at 13 °C for 16 days were studied. E-beam-treated fruit significantly suppressed the activities of chlorophyll degrading enzymes especially pheophytinase (PPH) and chlorophyll degrading peroxidase (Chl-POX) in the late stage of storage. This resulted in the chlorophyll content being maintained. However, E-beam irradiation did not affect the activities of chlorophyllase (Chlase) and magnesium de-chelatase (MD). The respiration rate, ethylene production, ROS accumulation (hydrogen peroxide [H2O2] and superoxide radical [O−.2]) immediately increased after E-beam treatment, following which they significantly decreased in comparison to the control. E-beam treatment enhanced the fruit’s antioxidant capacity by activating the activities of catalase (CAT) and ascorbate peroxidase (APX) and glutathione (GSH) content, and inactivated the activity of superoxide dismutase (SOD). Further, it did not affect the activity of glutathione reductase (GR) and glutathione disulfide (GSSG), vitamin C content, or total phenolic content. These results imply that E-beam treatment has the potential to delay chlorophyll degradation by suppressing the Chl-POX and PPH activities as well as reduce ROS production via CAT, APX, and SOD activities and GSH content.

Impact of Electron Beam Irradiation on Thermoplastic Polyurethanes Unraveled by Thermal Field-Flow Fractionation

The impact of electron beam irradiation on thermoplastic polyurethane material was studied for both an aliphatic and an aromatic polyurethane with approximately equal molar amount of hard and soft segments. Irradiation doses up to 300 kGy (kilogray) at room temperature and at 100 °C were applied. Changes in chemical structure, molar mass and size were assessed using infrared spectroscopy, differential scanning calorimetry, size-exclusion chromatography and thermal field-flow fractionation. Material alterations were correlated with trends regarding to degradation, crosslinking or branching changes. Thereby, limits of characterization by size exclusion chromatography are addressed and amended by thermal field-flow fractionation studies. In addition, a thermophoretic analysis has been carried out complementary to the portfolio of analytical methods applied in this work.

The Impact of Electron Beam Irradiation in Topaz Quality Enhancement

Most of the natural topaz is found as colorless. Variety attempt have been used to change its color. In this study, the process of enhancement by electron irradiation be carefully taken by consideration on the optimization of power and energy of electron, efficient cooling system, annealing process and radioactivity occurring and remaining. Electron irradiation was performed on topaz originated from Yen Bai province, in Vietnam. The two of topaz sample were irradiated by 20 MeV electron beam (e-beam) with different fluences of 1.34×1016 cm−2 and 2.64×1016 cm−2, respectively. The characteristic spectra obtained from the investigation compared to the natural topaz sample afterwards. Interaction of radiation with impurity ions in topaz sample during irradiation resulted in changing of colorless to sky blue topaz, which had the broad absorption band of UV-Vis spectroscopy at 620 nm. The ESR spectrum of topaz sample showing a single broad isotropic line with g = 2.012 that are correlated with an O-center in the topaz structure. FTIR spectra indicated that sky blue color may originate from the decomposition of hydroxyl group (OH) by the electron beam irradiation.

Impact of electron-beam irradiation on the quality characteristics of raw ground beef

Abstract The aim of this study was to evaluate the effects of different irradiation doses (0–4.5 kGy) on the quality of raw ground beef. The results showed a significant increase in lipid oxidation and protein oxidation after irradiation, and color fading was observed only at 4.5 kGy irradiation. The increasing spermidine did not trigger any food safety panic button in irradiated raw ground beef, but this issue should be taken into consideration in irradiated cured meat products. Electronic tongue detected higher saltiness in irradiated meat due to increased drip loss by irradiation. Due to the synergistic effect of saltiness on umami, an unexpected increase in umami taste was observed at 4.5 kGy. Dimethyl disulfide produced from the sulfur-containing amino acids, the major irradiation processing biomarker, was only detected at 4.5 kGy irradiation. Thus, electron beam irradiation

Impact of Electron Beam Irradiation on the Bioactive Principles of Seeds of Coastal Sand Dune Wild Legumes (Canavalia spp.).

Recent patents reveal that vegetable ingredients have several applications in novel food formulations. Many so-called antinutritional components (e.g. tannins, saponins, lectins and protease inhibitors) have nutraceutical as well as pharmaceutical significance. Seeds of two wild legumes of the genus Canavalia inhabitants of the coastal sand dunes of Southwest India are known for a variety of bioactive principles (e.g. phenolics, tannins, canavanine, concanavalin and phytohemagglutinins). This study evaluates the impact of Electron Beam (EB) irradiation on the bioactive components of seeds of two coastal sand dune wild legumes Canavalia cathartica and C. maritima. The dry seeds of C. cathartica and C. maritima were EB irradiated with different doses (2.5, 5, 10 and 15 kGy) to follow changes in six bioactive principles (total phenolics, orthodihydric phenols, tannins, canavanine, trypsin inhibitors and phytohemagglutinins) in comparison to control seeds. One-way ANOVA was employed to follow the variation in bioactive components of seeds in control and different doses of irradiation. Seeds of both legumes were devoid of orthodihydric phenols and trypsin inhibitors. In C. cathartica, the total phenolics showed significant dose-dependent increase up to 5 kGy and decreased thereafter. Tannin content was not altered up to 10 kGy followed by significant decrease at 15 kGy. There was no significant change in canavanine content and the phytohemagglutinin activity against human erythrocytes was not altered. Seeds of C. maritima did not show significant changes in total phenolics as well as tannin contents. The content of canavanine showed significant dose-dependent increase up to 5 kGy followed by significant decrease. There was no variation in phytohemagglutinin activity against erythrocytes A, B and O, while against AB, the activity decreased at 2.5 kGy and further decrease was constant at higher doses. The EB irradiation doses employed have selectively altered the bioactive principles of Canavalia seeds and such treatments may facilitate to maneuver desired medicinal, nutritional, functional and cooking properties. Besides selective changes in bioactive components the seeds have extended shelf life.

Impact of Electron-Beam Irradiation on Functional Attributes of Seeds of Two Coastal Wild Legume Landraces of Canavalia

Vegetable proteins have widespread application in the food industry as functional ingredients in food formulations according to the recent patents. Requirement to develop less expensive protein-rich supplementary foods has resulted in shift of emphasis towards lesser known wild than popular legumes. The aim of this study is to expose seeds of two coastal sand dune wild legumes of the Southwest India (Canavalia cathartica and C. maritima) to different doses of electron-beam (EB) irradiation to assess changes in functional attributes. Intact dried seeds were exposed to EB irradiation (2.5, 5, 10, 15 kGy). Protein solubility, gelation concentration, water-absorption capacity, oil-absorption capacity, emulsion properties and foam properties of control and irradiated seeds were assessed by standard methods. Protein solubility of both seed flours attained the highest at 2.5 kGy, followed by gradual dosedependent decrease. The gelation concentration increased in C. cathartica only at 5 kGy, while it decreased in C. maritima at 2.5 kGy without further change at higher doses. The water-absorption capacity of C. maritima was significantly higher than C. cathartica in control sample, while at 15 kGy C. cathartica showed significantly higher absorption capacity than C. maritima. The oil-absorption capacity was significantly higher in C. maritima than C. cathartica in control as well as all doses of irradiation. Emulsion activity of C. maritima was slightly higher than C. cathartica in control and irradiated samples, while both seeds showed similar emulsion stability in control with significant increase in C. cathartica at 10 kGy and 15 kGy. The foam capacity in both seeds was similar up to 2.5 kGy followed by significant increase in C. maritima at 5 kGy and 10 kGy. The foam stability was significantly higher C. cathartica than C. maritima in control as well as in irradiated samples. The foam capacity was higher in C. maritima than C. cathartica in control and irradiated samples, which showed gradual time-dependent decrease in stability with higher stability at 8 hr in C. cathartica than C. maritima. Improved functional properties (protein solubility, emulsion stability and foam capacity) and decreased gelation concentration in seeds of C. maritima irradiated at 5 kGy is advantageous in the production of functional foods. Even though both species of Canavalia grew on the coastal sand dunes and their seeds were exposed to same doses of radiation, they differed in functional attributes confirm that it is species-specific. Canavalia seeds being rich in proteins, carbohydrates, essential amino acids, essential fatty acids and bioactive components, further studies on the impact of EB irradiation helps in optimization of nutraceutical potential as well as functional attributes for future applications.

Optimization of mechanical, thermal and hydrolytic degradation properties of Poly (lactic acid)/Poly (ethylene-co-glycidyl methacrylate)/Hexagonal boron nitride blend-composites through electron-beam irradiation

Abstract The main objective of this work is to investigate the influence of electron beam irradiation on mechanical, thermal and hydrolytic degradation properties of Poly (lactic acid) (PLA)/Poly (ethylene-co-glycidyl methacrylate) (PEGM)/Hexagonal boron nitride (HBN) blend-composites for optimizing the properties. The previous studies have reported that the blending of PLA and PEGM with weight ratio (PLA: PEGM) (80:20) reduce the brittleness and improve the toughness. However, the heat deflection temperature (HDT) and other tensile properties were found to be reduced. It was found that HDT can be improved with the incorporation of HBN particles. So far, the effect of PLA/PEGM blending on the hydrolytic degradation properties of PLA was not studied. Hence, in the present work, the hydrolytic degradation test on prepared blend and blend-composites was performed. It is observed that blending of PEGM with PLA significantly retards the hydrolytic degradation of PLA. Further reduction in the hydrolytic degradation of PLA was observed in the blend-composites. To analyze the impact of electron beam irradiation, the prepared specimens of pure PLA, PLA/PEGM blend and PLA/PEGM/HBN blend-composites were irradiated to high energy (4.50 MeV) electron beam (E-beam) at different radiation doses. It is observed from the DSC thermograms of irradiated PLA, PLA/PEGM blend and PLA/PEGM/HBN blend-composites; the glass transition temperature (Tg) is shifted to higher temperature with irradiation. This is attributed to the polymer chains scission and crosslinking caused by E-beam irradiation. Interestingly, the E-beam irradiated blend-composites having a high HBN concentration (i.e. 5 phr and 10 phr) showed higher Tg as compared to the other unirradiated and irradiated samples. Further, the notched impact strength and HDT were remarkably improved with E-beam irradiation in the case of 5 phr and 10 phr blend-composites. The improvement in the yield strength and tensile modulus has also been noticed in the case of E-beam irradiated blend-composites as compared to unirradiated blend-composites. The E-beam irradiation of prepared blend and blend-composites also helps to accelerate the hydrolytic degradation. The E-beam irradiated PLA/PEGM/HBN 5 phr blend composite shows high HDT, high notched impact strength, good yield strength, better tensile modulus and also exhibit fast hydrolytic degradation as compared to the other E-beam irradiated blend and blend-composites and unirradiated PLA. Hence, the E-beam can be employed to optimize the mechanical, thermal and degradation properties of the final product as per the desired application.

The impact of electron beam irradiation on Low density polyethylene and Ethylene vinyl acetate

Improvement of measured gel content, hardness, tensile strength and elongation at break of Ethylene vinyl acetate (EVA) have confirmed positive effect of electron beam irradiation on EVA. Results obtained from both gel content tests show that degree of cross-linking in amorphous regions is dependent on dose. A significant improvement in tensile strength of neat EVA samples is obtained upon electron-beam radiation up to 210 kGy. Similarly, hardness properties of Low-density polyethylene (LDPE) improvewith increasing electron beam irradiation. This article deals with the impacts of electron beam (EB) irradiation on the properties of LDPE and Ethylene-Vinyl Acetate (EVA) as the two common based formulations for wire and cable applications.

A Novel Approach for Preparation and In Situ Tensile Testing of Silica Glass Membranes in the Transmission Electron Microscope

The mechanical behavior of glasses in the micro- and/or nanometer regime increasingly gains importance in nowadays modern technology. However, suitable small scale preparation and mechanical testing approaches for a reliable assessment of the mechanical properties of glasses still remain a big challenge. In the present work, a novel approach for site-specific preparation and quantitative in situ tensile testing of thin silica glass membranes in the transmission electron microscope is presented. Thereby, advanced focused ion beam techniques are used for the preparation of nanoscale dog bone shaped silica glass specimens suitable for in situ tensile testing. Small amounts of gallium are detected on the surface of the membranes resulting from redeposition effects during the focused ion beam preparation procedure. Possible structural changes of silica glass upon irradiation with electrons and gallium ions are investigated by controlled irradiation experiments, followed by a structural analysis using Raman spectroscopy. While moderate electron beam irradiation does not alter the structure of silica glass, ion beam irradiation results in minor densification of the silica glass membranes. In situ tensile testing of membranes under electron beam irradiation results in distinctive elongations without fracture confirming the phenomenon of superplasticity. In contrast, in situ tensile testing in the absence of the electron beam reveals an elastic/plastic deformation behavior, and finally leads to fracture of the membranes. The Young’s moduli of the glass membranes pulled at beam off conditions in the TEM are comparable with values known for bulk fused silica, while the tensile strength is in the range of values reported for silica glass fibers with comparable dimensions. The impact of electron beam irradiation on the mechanical properties of silica glass membranes is further discussed. The results of the present work open new avenues for dedicated preparation and nanomechanical characterization of silica glasses, and further contribute to a fundamental understanding of the mechanical behavior of such glasses when being scaled down to the nanometer regime.

Impact of electron beam irradiation on fish gelatin film properties

The objective of this work was to display the effect of electron beam accelerator doses on properties of plasticized fish gelatin film. Electron spin resonance indicates free radical formation during irradiation, which might induce intermolecular cross-linking. Tensile strength for gelatin film significantly increases after irradiation (improved by 30% for 60kGy). The vapour permeability is weakly affected by irradiation. Surface tension and its polar component increase significantly and are in accordance with the increase of wettability. So, irradiation may change the orientation of polar groups of gelatin at the film surface and crosslink the hydrophobic amino acids. No modification of the crystallinity of the film is observed. These findings suggest that if structure changes, it only occurs in the amorphous phase of the gelatin matrix. It is also observed that irradiation enhances the thermal stability of the gelatin film, by increasing the glass transition temperature and the degradation temperature.

Impact of electron-beam irradiation on free-volume related microstructural properties of PVA:NaBr polymer composites

Sodium Bromide doped Poly(vinyl alcohol) (PVA:NaBr, 80:20) polymer composite films were prepared using a solution casting method. These films were subjected to 8MeV electron beam radiation at a dose of up to 300kGy in air at room temperature. The free volume related microstructural and electrical properties of these irradiated films were studied using various characterization methods, such as positron annihilation lifetime spectroscopy (PALS) and AC & DC conductivity measurement techniques. The variations in the positron lifetime data indicate that the free-volume related properties of the doped polymer are affected by irradiation. From the results, it is found that at lower doses, a cross-linking network provides hopping sites for Na+ ions, and at higher doses, the chain-scission process facilitates ionic transport through segmental motion. Thus, the free volume around the polymer chain leads to mobility of the ions as well as the polymer segments and hence contributes to the enhancement of conductivity.

Electronic and vibrational spectra of tourmaline – The impact of electron beam irradiation and heat treatment

Irradiation and heat treatment were performed on tourmalines of various colors from Antandrokomby, Madagascar. The samples were irradiated with 10MeV electrons to fluencies of 2 ×1017cm−2 for 1h and were heated at 550°C for 3h in air. Their electronic and vibrational spectra were investigated by UV–vis, mid-infrared, and WD-XRF spectroscopy for comparison to pristine samples. Changes in the Mn3+ ions after irradiation resulted in darker pink tourmalines, which had absorption peaks at 390 and 520nm. These samples became colorless after subsequent heat treatment. After irradiation, colorless, light blue and yellow tourmalines displayed a new absorption band at 365nm. Alteration of the stretching absorption bands and wavenumber after irradiation could be explained by the following reactions:OH−+e− beam irradiation→O−+H°,Mn2++e− beam irradiation→Mn3++e− andFe2++e− beam irradiation→Fe3++e−.Stretching vibration of the BO3 structure occurred at 1330cm−1, while the SiO vibration absorption bands were assigned to around 1100cm−1. Colorless, green, and yellow tourmalines showed high-intensity peaks around 3608 and 3505cm−1 after irradiation. Pink and dark green tourmalines showed low-intensity peaks at 3605 and 3585cm−1, respectively. The combination modes of stretching and bending in the range of 4600–4300cm−1 were split after irradiation and heat treatment, and different color changes occurred after irradiation.

Impact of Electron Beam Irradiation on Fatty Acid Profile of Canavalia Seeds

The present study provided an evidence for selective changes of the fatty acid methyl esters (FAMEs) of Canavalia seeds and the low doses of electron beam irradiation (EBI; 2.5 and 5 kGy) serve as hormetic doses for selective enhancement of fatty acids. The total lipids and FAMEs of irradiated Canavalia cathartica and Canavalia maritima seeds of the coastal sand dunes of Southwest India were assessed using soxhlet extraction and chloroform–methanol–water extraction (Bligh and Dyer) methods followed by gas chromatography. As the EBI dose increased, total lipid extraction decreased by soxhlet method in seeds of C. cathartica, while it was reverse in C. maritima. Among the doses, 5 and 10 kGy resulted in the highest extraction of lipid by the Bligh and Dyer method in C. maritima and C. cathartica, respectively. A great variation in FAMEs profile of Canavalia seeds subjected to EBI was seen by the soxhlet and Bligh and Dyer methods of extraction. The EBI increased saturated fatty acids in both the seeds. The unsaturated fatty acids were decreased by EBI based on the soxhlet extraction (except for 15 kGy in C. maritima), while a dose-dependent increase was shown by the Bligh and Dyer method on attaining the highest at the doses 5 kGy (C. maritima) and 10 kGy (C. cathartica). The changes in medium chain fatty acids, long chain saturated fatty acids, mono- and polyunsaturated fatty acids, and ratios of fatty acids were dependent on the seed material, the dose EBI, and the method of extraction.