Different Doses Of Gamma Radiation Research Articles

Biological and Technological Effects on Mulberry Silkworm, Bombyx mori (Bombycidae) Exposed to Different Low Doses of Gamma Radiation

The present work was carried out to study the effect of low doses of gamma radiation (25, 50, 75, 100 rads) on mulberry silkworm eggs and pupae. Mortality, larval duration, weights of 3rd, 4th and 5th instar larvae, weight of fresh and dry cocoons, weight and length of silk filament and fecundity and fertility of eggs were studied. The egg hatch was not affected by different low doses of gamma radiation and no abnormalities or mortality were observed during the different life stages. Mortality reached 10% by the 5th instar. The larval duration was affected with different doses of gamma radiation, 25, 50, 75 and 100 rads. The duration was 27, 26, 27 and 28 days respectively, as compared with the control (28 days). The highest mean weights of larvae and cocoons were 3.26g and 1.416g respectively, and the maximum length of the silk filament was 1148m. These values were obtained when eggs were exposed to 50 rads. The lowest mean weights were 2.54g for larvae and 1.134g for pupae, with a minimum length of 853m for the silk filament, obtained at 100 rads. On the other hand, the highest fecundity occurred when eggs and pupae were exposed to 50 rads and showed no difference between irradiated egg only and when both eggs and pupae were irradiated.

Improvement of microbiological quality, antioxidant content and shelf life of jujube (Ziziphus mauritiana cv. BAU Kul) fruit by gamma irradiation

Postharvest loss of inherently perishable fruits is a matter of serious concern for the farmers and traders. Reduction of postharvest loss is one of the key components for ensuring food security. A study was carried out to reduce the postharvest loss of BAU Kul, an improved variety of jujube fruit (Ziziphus mauritiana), by using gamma irradiation. Different doses of gamma irradiation (0.5, 1.0 and 1.5 kGy) was applied to the jujube fruit samples and the microbiological quality, antioxidant content and shelf life of those fruits were evaluated. Gamma irradiation initially caused significant reduction of the total heterotrophic bacteria, coliform as well as yeast and mold counts. However, the counts increased in both irradiated and non-irradiated fruit samples with the passage of storage period but the increment was significantly less in the 1.5 kGy irradiated samples. Irradiation played active role in the enhancement of total phenolics and flavonoids contents. The concentration of these antioxidants remained higher in irradiated samples in comparison to non-irradiated control samples throughout the storage period. However, the ascorbic acid content decreased gradually with the increase of radiation dose and storage period. The overall acceptability of the fruit samples was determined by the taste-taking panelist. The irradiated (1.0 and 1.5 kGy) fruits were acceptable up to 8 days whereas control and 0.5 kGy irradiated fruits lost their acceptability during storage. The study revealed that 1.5 kGy irradiation can improve microbiological quality and extend the shelf life of jujube fruits (cv. BAU Kul) without significant loss of overall antioxidant content and sensory attributes.

Effects of sub-lethal gamma irradiation on antibiotic susceptibility profile and population dynamics of Enterococcus faecalis and Escherichia coli in water

Disinfection of water is important in the control of waterborne diseases. It is used to kill or inactivate microorganisms in a gradual process that involves a number of physical–chemical and biochemical processes. The effects of sub-lethal gamma irradiation on survival and resistant pattern of two indicator organisms used in assessing water quality: Enterococcus faecalis and Escherichia coli were investigated in this study. Plate count agar and disc diffusion methods were used to determine the load and antibiotics susceptibility pattern of the test organisms respectively before and after exposure to different doses of gamma irradiation in sachet water samples. Survival pattern of the two indicator organisms to gamma- ray showed a decline in the populations of the organisms with time compared to the controls (non-radiated). The effect of the irradiation on the E. coli was dose dependent, it initially responded to the effects of the irradiation in the first 4 days of exposure compared to the control. On exposure to 4 and 5 gy gamma rays a minimum population was reached on the 7th day. At p<0.05 the population of E. coli was significantly different from the control. The survival pattern of Ent. faecalis also followed a similar growth pattern. The application sub-lethal gamma irradiation did reduce the population of the isolates and also affect the antibiotic susceptibility of the isolates.

Gamma irradiation protect the developing wheat endosperm from oxidative damage by balancing the trade-off between the defence network and grains quality

Gamma irradiation has been reported to modulate the biochemical and molecular parameters associated with the tolerance of plant species under biotic/ abiotic stress. Wheat is highly sensitive to heat stress (HS), as evident from the decrease in the quantity and quality of the total grains. Here, we studied the effect of pre-treatment of wheat dry seeds with different doses of gamma irradiation (0.20, 0.25 and 0.30 kGy) on tolerance level and quality of developing wheat endospermic tissue under HS (38 °C, 1 h; continuously for three days). Expression analysis of genes associated with defence and starch metabolism in developing grains showed maximum transcripts of HSP17 (in response to 0.25 kGy + HS) and AGPase (under 0.30 kGy), as compared to control. Gamma irradiation was observed to balance the accumulation of H2O2 by enhancing the activities of SOD and GPx in both the cvs. under HS. Gamma irradiation was observed to stabilize the synthesis of starch and amylose by regulating the activities of AGPase, SSS and α-amylase under HS. The appearance of isoforms of gliadins (α, β, γ, ω) were observed more in gamma irradiated seeds (0.20 kGy), as compared to control. Gamma irradiation (0.25 kGy in HD3118 & 0.20 kGy in HD3086) was observed to have positive effect on the width, length and test seed weight of the grains under HS. The information generated in present investigation provides easy, cheap and user-friendly technology to mitigate the effect of terminal HS on the grain-development process of wheat along with development of robust seeds with high nutrient density.

Effect of Nano-Filler Content and Fiber Treatment on the Characteristics of Gamma-irradiated Rice Husk-Epoxy Particleboard Composites.‎

In this study, both untreated and treated rice husk fibers with a silane coupling agent are incorporated with epoxy resin to prepare particleboard composites. The effect of different ratios of nanoclay 5%, 10%, 15%, and 20% (by the weight of the polymer) on the physicomechanical properties of the prepared particleboard composites is investigated. The results show that the flexural, and impact strengths as a function of mechanical properties getting better with increasing nanoclay content up to 10%. While the addition of nanoclay to the samples decreases the water absorption percentage. This decrease is almost constant with nanoclay (%). In addition, the effect of different doses of gamma-irradiation on the properties of both untreated and treated rice husk-epoxy particleboard composites that containing 10% of nanoclay is also discussed. The results show that the irradiated specimens at a dose of 10kGy achieved a good enhancement in mechanical properties whereas the water absorption percentage as a physical property decreases at a dose of 10kGy and starts to increase with increasing gamma irradiation doses. TGA, and SEM are carried out to confirm the data obtained.

Induced defects by gamma irradiation doses on the structure and optical behavior of undoped and TiO2-, Cr2O3-, or MnO-doped heavy metal borate glasses

A series of un-doped and TiO2-, Cr2O3- or MnO-doped heavy metal borate glasses were prepared by the conventional melt annealing method. The prepared glasses were examined via optical absorption measurements in the UV–visible region. The optical absorption spectra before and after gamma irradiation show a fixed characteristic peak in the UV region with other extended peaks in the visible region caused by the addition of the selected transition metal ions; Ti4+, Cr3+, or Mn2+. The obtained optical band gap values reveal an observed decrease as a result of both the addition of such transition metal ions and the effect of increasing the dose of gamma radiation. Infrared absorption spectra (FTIR) were applied to identify the environmental structure of the prepared glasses before and after different doses of gamma radiation. Results of IR spectra show that both BO3 and BO4 are the basic building units, in addition to PbO4 units. Electron spin resonance (ESR) and some of glasses physical parameters like density, oxygen packing density, molar and specific volumes were also investigated and revealed the good stability of the prepared glasses towards different doses of gamma radiation because of the high content of heavy metal Pb2+ ions.

Effect of gamma irradiation on the physical and structural properties of basalt fiber.

Digital holographic interferometry (DHI), X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR) and scanning electron microscopy (SEM) were used to study the effects of gamma irradiation on the physical and structural properties of basalt fibers. For this purpose, set samples of basalt fibers were subjected to different doses of gamma irradiation (3, 10, 25, and 40 kGy). The Mach-Zehnder interferometer was used to capture holographic patterns which are used then to determine the unwrapped phase. From the unwrapped phase distributions, the optical path difference within the irradiated basalt samples was determined. Thus, refractive indices, and birefringence of irradiated basalt fibers were determined at different irradiation doses using DHI method. XRD technique was used to investigate the effect of irradiation doses on the crystalline behavior of fibers. FTIR was performed to each of the basalt samples to evaluate the changes in the surface chemical properties due to radiation exposure doses. The morphology of irradiated fibers was examined using SEM. The results indicate that basalt fiber has a resistance to gamma radiation. There are no significant effects on the physical, structural and chemical properties were demonstrated of basalt fibers in the doses range of irradiation.

Efficiency of the Gamma Irradiation in Controlling the Red Flour Beetles, Tribolium castaneum Herbst, and Preventing Its Secondary Infestations

The present study was carried out to investigate the effect of different doses of gamma irradiation (0, 50,100,500 and 1000 Gy) on the mortality percentage of both of larvae and adult stages of the red flour beetle, Tribolium castaneum Herbst. (Coleoptera- Tenebrionidae). Also, the effect of gamma irradiation on both of the Quinones secretion and the microflora associated with the pest stages was investigated. The results showed that the incremental of adult and larval mortality percentages were significant (P <0.05) affected by an increment of gamma irradiation dose. The results of Gas chromatography-mass spectrometry patterns exhibited a strong inhibitory effect of irradiation on Quinones secreted by both stages. The used doses succeed in reducing the count of microflora were associated with both larval and adult stages. This reduction reached zero for fungi and bacteria isolated from the surface at the dose 1000 Gy. Obtained data suggested that the irradiation of red flour beetles with 1000 Gy is a promising tool for the control of this destructive pest and prevent its harmful effects associated with its infestation.

Effect of Different Doses of Gamma Irradiation on Vegetative Growth and Oil Yield of Ocimum basilicum L.

Gamma irradiation is important agent used to improve the productivity and quality of many plants. The present study was carried out to evaluate the effectiveness of different doses of gamma rays (0, 5, 10, 15, 20, 25, 30 kR) on germination percentage, vegetative growth, photosynthetic pigments, oil yield, oil components and total phenolic content of Ocimum basilicum L during the two successive seasons of 2017 and 2018 at the Experimental Farm of Sakha Horticulture Research Station, Kafr El-Sheikh Governorate, Egypt. Results showed that low doses of gamma irradiation significantly increased germination percentage, plant height, number of branches, fresh and dry weight per plant and per fed, chlorophyll a and chlorophyll b, essential oil percentage, oil yield per plant and per fed and essential oil main components. Increasing gamma rays doses significantly reduced germination percentage, vegetative growth characters and oil yield while total carotenoids content and total phenolic content significantly increased as a defensive effect to the increase in irradiation doses. The study suggested 10kR dose as seeds treatment for increasing basil plants production through enhancing germination percentage, vegetative growth, fresh yield, essential oil yield and essential oil components.

Impact of gamma irradiation on tissues of the mud crab, Scylla serrata (Forskål, 1775) (Decapoda, Portunidae) — electron microscopic study and DNA comet assay

Abstract Radiopreservation using gamma radiation is widely in use as a safe method for extending the shelf life of shellfish. This study explored the consequences of different doses of gamma radiation (0.5 kGy, 1.0 kGy and 2.0 kGy) on various tissues of Scylla serrata at cellular and nuclear level, with the aid of electron microscopy and DNA comet assay. The highly radio exposed (2.0 kGy) pyloric muscles showed a reduction in sarcomere length, disordered organization with expanded gap between adjacent myofibrils, ruptured sarcotubular system, mitochondrial swelling with crushed cristae, significant increase in nucleus size coupled with less dense nucleoplasm, etc. Comet assay on tissues such as muscle, hepatopancreas and testis irradiated with 2.0 kGy radiation also revealed a significant degree of nuclear damage by gamma irradiation in a dose-dependent manner. The tail length of the comet showed a tissue-specific tolerance level. The present study clarified the precise dose of irradiation as 1.0 kGy and the results can be relevant for commercial purposes to qualitatively categorize the irradiated crabs.

Effect of gamma irradiation and/or certain entomopathogenic fungi on the larval Mortality of Galleria mellonella L

The present investigation was carried out to study the effect of LC50 of the entomopathogenic fungi (EPF), Paecilomyces lilacinus and Beauveria bassiana, on larval mortality of the greater wax moth (GWM), Galleria mellonella L., under laboratory conditions and also to study the effect of different doses of gamma irradiation (70, 100, 125, and 150 Gy), separately or combined with the LC50 of the isolates of the EPF, B. bassiana, and P. lilacinus, on the second-instar larvae of G. mellonella larval mortality. The combined treatment of gamma irradiation and EPF increased the larval mortality rates than that at each treatment alone. The highest percentage of larval mortality was 78 and 84%, with 125 Gy + B. bassiana in the case of F1 male and F1 female, respectively. According to the obtained results, the gamma irradiation increased the pathogenicity of the fungi against the tested larvae. The combination between the two control tools may provide satisfactory control of the insect-pest, especially, in the storage.

Effect of gamma irradiation dose on the structure and pH sensitivity of ITO thin films in extended gate field effect transistor

Abstract Even though several studies have demonstrated the use of Indium Tin Oxides (ITO) as an extended gate field effect transistor (EGFET), the effect of different doses of gamma radiation on the intrinsic properties of the ITO films has not been considered. This study investigates the effect of gamma irradiation on the structural, optical, morphological and electrical properties as well as pH sensitivity (as an extended gate field effect transistor) of ITO thin films. ITO thin films with thickness of 400 nm were prepared using a radio frequency sputtering technique. The samples were then subjected to various doses of gamma radiation from a Co-60 radio-isotope (0.5 kGy, 1 kGy, 1.5 kGy, and 2 kGy). The structural and morphological changes as well as transmission and absorption of the thin films were analyzed using X-ray diffraction (XRD), Atomic Force Microscopy (AFM), Field-Emission Scanning Electron Microscope (FESEM) and UV–Vis spectrophotometry, before and after irradiation. The irradiated ITO thin films were then used as an extended gate field effect transistor to determine its ability to improve sensitivity as pH sensors. The grain size and transmittance in the range 300–900 nm of the ITO films were found to decrease with increasing gamma irradiation dose. In contrast, the uniformity and surface roughness of ITO thin films increased with increasing gamma radiation dose due to the formation of lattice defects. Moreover, the electrical resistance of the thin films increased with increasing dose because of the low current density and high number of surface defects associated with irradiation. The pH sensitivity of the ITO thin films improved after irradiation, possibly due to the concomitant increase in surface roughness with increasing radiation dose. The improvements in the pH sensitivity of ITO thin films after irradiation justify their potential use as pH sensors.

Effects of gamma radiation exposure on PANI-Fe(X) -Ni(1−X) (X = 0.2,0.4,0.6,0.8) nanocomposite thin film for Leptospira detection

The aim of this research is to develop a PANI-Fe-Ni nanocomposite thin film sensor for pathogenic and saprophytic Leptospira detection. In this study, Leptospira detection is distinguished at concentrations of 108 CFU ml−1, 107 CFU ml−1, 106 CFU ml−1, and 105 CFU ml−1 respectively. PANI-Fe-Ni nanocomposite is spin-coated on a glass substrate to form a thin film sensor. The samples were later exposed to different doses of gamma radiation which were 15 kGy and 30 kGy. This is done to analyze the effects of gamma radiation on the sensitivity of the sensor. The morphology of the thin film was characterized using scanning electron microscope (SEM) and atomic force microscopy (AFM). The sensor performances were measured using current-voltage (I-V) and electrochemical impedance spectroscopy (EIS). The measurement was taken by immersing the sensor into the Leptospira solution. According to the result, the surfaces of the thin film shrink to form agglomeration due to the gamma radiation. Besides that, observation under atomic force microscopy (AFM) shows increment in the grain size of of PANI-Fe-Ni nanocomposite. Furthermore, surface roughness of thin film sensor increased when Fe quantity increased. The study found that there is an increase in current and voltage readings when the thin film sensor is exposed to the Leptospira bacteria proving that the sensor works. It was deduced that samples of PANI-Fe0.8-Ni0.2 were the most suitable to be used as thin film sensor. Current and voltage tests showed that samples that were not exposed to radiation are more sensitive.

Radiation effects on luminescent and structural properties of YPO4: Pr3+ nanophosphors

ABSTRACTYPO4 phosphors doped with trivalent ion Pr3+ were prepared by sol–gel method and treated with different doses of gamma radiation, from 0.25 MGy to 4 MGy. Effects of radiation on morphology, structure and luminescent properties were analyzed. Also, the influence of radiation on the change in the color of the samples was examined. The color efficiency of powders was evaluated by colorimetric analysis (CIE and L * a * b system). It has been observed that powders change color under the influence of radiation, i.e. they pass from white to pinkish red. Also, it has been determined that the radiation affects morphology change, as the particle size increases with increasing of the radiation dose. With the increase in the radiation dose, the emission intensity of samples decreases. The structure remains almost unchanged after irradiation, and the intensity constantly decreases with increasing of dose.

Physiological and biochemical responses of Makhana (Euryale ferox) to gamma irradiation.

The impact of gamma irradiation on growth and physiology of Euryale ferox was described in the present investigation. E. ferox is an underutilized aquatic food crop that grows in shallow-water bodies in lower Assam regions and north Bihar of India. The seeds of E. ferox were irradiated with different doses of gamma irradiation ranging from 0 to 500Gy. It was observed that the germination and survival percentage was inhibited by increasing the irradiation dose. However, plants developed from seed exposed to an irradiation dose beyond 100Gy did not survive more than 1month. Further growth parameters (leaf size and number, number of thorns, root number and length, and number of flower and seeds) were also compared with respect to non-irradiated plants. Physiological parameters, viz. chlorophyll a, chlorophyll b, total chlorophyll, photosynthetic rate, transpiration rate, stomatal conductance, and intracellular CO2 content was higher in the irradiation population of E. ferox. Superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities were observed low in irradiated population of E. ferox. The proline and glycine betaine content was enhanced with increasing the irradiation dose. The present investigation explores the potential use of gamma rays in genetic improvement of E. ferox and improves understanding of the physiological responses inflicted by gamma irradiation.

Effect of Gamma Radiation Induced on Structural, Electrical, and Optical Properties of N, N′-Dimethyl-3,4,9, 10-Perylenedicarboximide Nanostructure Films

N,N′-Dimethyl-3,4,9,10-perylenedicarboximide (PTCDI-C1) thin films were first prepared by thermal evaporation technique. Then, the prepared films were irradiated with gamma rays at room temperature with different absorbed doses. The structure of PTCDI-C1 films at different doses of gamma radiation was elucidated by x-ray diffraction. The results confirmed that PTCDI-C1 film has a nanostructure morphology. The grain size was observed to decrease slightly with increasing the gamma radiation doses. The temperature dependence of the electrical conductivity was measured in the temperature range of 293–423 K. It was found that the obtained activation energy of PTCDI-C1 films decreased with increasing gamma radiation dose. The optical parameters were obtained using spectrophotometric measurements. The single oscillator model of Wemple–Didomenico was adopted to study the normal dispersion of refractive index. The optical dispersion parameters of PTCDI-C1 films such as dispersion energy, oscillator energy and the high frequency dielectric constant were calculated. Furthermore, the nonlinear susceptibility values of PTCDI-C1 films at different gamma radiation dose were calculated. Also, the dielectric constants of the films were investigated in a large range of frequencies. The fundamental band gap energy values (3.91 eV Eg2 > 50 kGy).

Radio-protective dosimetry of Pangasius sutchi as a biomarker, against gamma radiation dosages perceived by genotoxic assays

Exposure to ionizing radiation is harmful to any living organism. It may cause varying levels of genetic mutation or ultimately death. Synthetic compounds have been used to counteract the hazardous effect of radiation on the live cells, but the possibility of these synthetic compounds being harmful to the organism being treated also exists. Herbal formulations are thus being explored as a possible alternative for the synthetic radioprotectant. Induction of DNA damage in fishes caused by ionizing radiation and its protection by phytocompounds is a hardly studied topic. In this study, we analyzed the radioprotective effect of Gymnema sylvestre leaves extract (GS) and its active compound gymnemagenin (GG) against different doses of gamma radiation (60Co) on the freshwater fish Pangasius sutchi. The radioprotective efficacy was assessed by micronuclei and alkaline comet assays. The freshwater fish P. sutchi was pre-treated with intramuscular injection (IM) of amifostine (83.3 mg/kg of B.W.), GS (25 mg/kg of B.W.) and GG (0.3 mg/kg of B.W.), 1 h prior to the gamma radiation. The fishes were exposed to LD30, LD50 and LD70 of gamma radiation and the protection activities were assessed by analyzing the number of micronuclei (MN) and erythrocytic abnormalities in the blood after 2, 4, 8, 16 and 32 days after exposure. Compared to the irradiated fishes, frequency of erythrocytic abnormalities were decreased in response to the radio-protection in the amifostine treated groups for all three doses of gamma radiation (LD70 – 77.62%), (LD50 – 80.11%) and (LD30 – 82.30%); GS (LD70 – 62.66%), (LD50 – 69.74%) and (LD30 – 70.81%); and GG (LD70 – 49.42%), (LD50 – 53.43%) and (LD30 – 58.42%). Similarly, a significant radio-protective effect in terms of decremented DNA damage was observed using the comet assay after post exposure. The percentage of protection noted for amifostine was (LD70 – 58.68%), (LD50 – 64.52%) and (LD30 – 74.40%); GS (LD70 – 53.84%), (LD50 – 59.02%) and (LD30 – 65.97%); GG (LD70 – 49.85%), (LD50 – 52.56%) and (LD30 – 64.30%). From the current study, we can conclude that the radioprotective efficacy of the GS is similar to the synthetic compound (amifostine) and also greater than the bioactive compound (GG). The synergetic effect of the plant extract which leads to a better protection than the bioactive compound must be further studied. MN and Comet assays can easily identify the damage due to radiation exposure and thus can be used as predictive biomarkers for aquatic organisms exposed to radiation.

Effects of gamma irradiation on submergence tolerance of two selected varieties of lowland rice (Oryza sativa L.)

The study was carried out to assess the effect of different doses of gamma irradiation on agro-morphological traits under simulated flooding of two rice varieties (FARO 44 and FARO 60) in order to identify the most effective radiation dose in creation of genetic variability for submergence tolerance. Seeds of FARO 44 and FARO 60 cultivars were collected from National Cereal Research Institute (NCRI) Badeggi, Nigeria and exposed to different doses of gamma irradiation (0, 50,100, 150 and 200 Gy) at Center for Energy and Research Training, Zaria, Nigeria. The treated and the controls seeds were evaluated for submergence in a Randomized Complete Block Design with four replicate each. Each experimental bucket was flooded for a period of 10 days and was allowed to grow till harvest after submergence period. From the results, gamma irradiation had significant (P≤0.05) positive effect on survival percentage of FARO 44 after submergence with 150 Gy having the highest (93.75%) compared to the control (56.25%). The irradiation doses (150 and 200 Gy) had significant positive effects (p≤0.05) on the plant height and yield of FARO 44. In Faro 60, low doses of gamma irradiation (100 Gy) had significant (p≤0.05) effects on the days to 50% flowering and weight of 100 grains (g). It was observed that gamma radiation doses of 150 Gy and 200 Gy had positive effects on submergence tolerance indices of FARO 44 used in this research. Further research therefore should be carried out on submergence tolerance of the promising mutants.

Mechanical properties of gamma‐irradiated EPDM/Waste newsprint microfibers composites treated using acrylic styrene emulsion as a coupling agent

This study investigated the effect of gamma radiation and acrylic styrene emulsion as a coupling agent on mechanical properties of the ethylene propylene diene monomer (EPDM)/newsprint microfibers composite. The recycled newsprint paper was subjected to chemical pulping and the resulted micro fibers treated by using a different ratio of acrylic styrene emulsion (5, 10, and 15 wt% to the microfibers) before mixing with EPDM rubber matrix. The effect of the treated microfibers concentration, namely, 5 up to 50 phr (part per hundred part of rubber) and the effect of different doses of gamma radiation on the mechanical properties of the EPDM/newsprint microfibers composites was investigated. The newsprint microfibers structure and EPDM/treated microfibers composite were investigated using X‐ray diffraction and FTIR analysis. The results indicated that bonding had occurred between the treated microfibers and EPDM polymer matrix. EPDM/untreated newsprint microfibers composites have achieved higher mechanical properties than EPDM matrix up to 10 phr microfibers concentration and up to 60 kGy. Meanwhile, treatment of the newsprint microfibers by using acrylic styrene emulsion leads to improve mechanical properties of EPDM/treated microfibers composites higher than that of the EPDM/untreated fibers composites. Newsprint microfibers treated using 10% acrylic styrene and gamma irradiated at 60 kGy, was found to maintain a higher tensile strength, modulus of 100% strain and toughness. POLYM. COMPOS., 40:1209–1227, 2019. © 2018 Society of Plastics Engineers

Effect of Co-60 gamma radiation on optical, dielectric and mechanical properties of strontium L-ascorbate hexahydrate NLO crystal

A potentially useful nonlinear optical semi-organic single crystal of strontium L-ascorbate hexahydrate (SLAH) was grown by solution growth slow evaporation technique at room temperature. The grown crystal is semi transparent, yellowish in color with monoclinic crystal system having space group P21 and is stable up to 198°C. Further, SLAH crystals were irradiated with gamma rays produced by 60Co with different doses of 10 KGy, 30 KGy and 50 KGy at room temperature and then studied the effect of gamma-rays on dielectric properties, optical absorption, microhardness and SHG efficiency. The absorption study reveals that the absorbance of the grown crystal is appeared to be low throughout the visible region with a lower cutoff wavelength of 277nm and these parameters are not affected upon gamma irradiation. The luminescence intensity of the crystal is also not affected by the irradiation. There is noticeable changes were observed in dielectric properties and hardness of the materials for different doses of gamma irradiation. The second harmonic generation (SHG) efficiency of the grown crystal is 0.54 times that of the KDP crystal and is decreased moderately by increasing the dosage of gamma irradiation.