Increase In Gamma Dose Research Articles

Structural and optical analysis of gamma-induced modification in polycarbonate nuclear track detector

Makrofol BL 6–2 films were irradiated with gamma-doses from 45 kGy to 225 kGy. FTIR, surface roughness, UV/Vis and photoluminescence (PL) spectrometers were used to study the change in structure and optical properties of irradiated films. The FTIR spectra exhibit that the band intensities of chemical bonds of irradiated-films are affected by irradiation according to the value of gamma dose. An enhancement of the surface roughness parameters was observed in the irradiated-films. UV/Vis spectra showed that the optical absorption of irradiated films is shifted toward the lower photon energies with an increase in gamma-doses. This shift was associated with the decrease in energy gap. The obtained results of optical parameters are modified after irradiation. The PL results confirm that the photoemission property is modified by gamma-irradiation. The acquired results can help in modifying and modeling the properties of such irradiated polycarbonate films for their use in industrial and radiation dosimetric applications.

Gamma radiation induced microwave absorption properties of Ultra-thin barium titanate (BaTiO3) ceramic tiles over X-Band (8.2–12.4GHz)

We report the enhancement of microwave absorption properties in BaTiO3 ceramics induced by exposing under high energy gamma radiation at 5 kGy, 10 kGy and 15 kGy, gamma-ray doses in a properly shielded Co60 γ-radiation chamber. The tetragonality ratio (c/a) decreases with increasing gamma dose on powder samples together with the reduction of grain size from ~2 μm to ~0.5 μm. Further, the irradiated BaTiO3 powder based ceramic tiles are fabricated and electromagnetic (EM) measurements suggest increase in imaginary permittivity and loss tangent values (tanδe) at resonance frequency of ~8.8 GHz. Reflection loss (RL) plots of BT tiles showed enhancement in microwave loss at higher gamma radiation doses. As per the customized requirements, two type of extremely thin ceramic tiles are obtained viz. Resonating (RL> 40 dB at 9.6 GHz) and wide-band (RL> 8 dB over entire X-band) for their possible use for MW attenuation on different objects/platforms.

Disparate structural changes in the titanium dioxide thin film coated on the p-type Si and porous silicon textures after gamma irradiation

Gamma irradiation effects on the thin film of titanium dioxide (TiO2) coated on p-type silicon (Si) and porous silicon (PSi) by sol–gel spin coating technique is investigated for the gamma dose of 100 to 1000 mGy. Characterization studies by the X-Ray Diffraction, Fourier Transform Infrared and Photoluminescence spectroscopy, and I-V study revealed the measurable changes in structural, optical and electrical properties due to gamma irradiation which are disparate in the hetero-junction on silicon and porous silicon texture. The anatase phase of TiO2 experienced linear defects then the rutile phase structure. Band gap energy is decreased while the dielectric constant is increased with increase of gamma dose. The strain due to crystallization of sol–gel of TiO2 on Si substrate is higher than the PSi substrate and found to be changed after irradiation. Porous texture is found to be suitable for formation of larger crystallite with less strain which can provide mechanical stability.

Synergistic effects of gamma irradiation on the PET surface and heat treatment of hydrotalcite catalyst supported by Pt/TiO2 nanoparticles on PET depolymerization rate

Acquiring new methods to achieve the products with lesser molecular weight associated with minimum energy consumption in poly(ethylene terephthalate) (PET) recycling can improve the glycolysis reaction performance. The synergistic effects of gamma irradiation on the properties of PET wastes and heat treatment on the catalytic activity of novel hydrotalcite supported by 2‐wt% Pt/TiO2 nanoparticles (NPs) were studied. The PET samples treated by different gamma irradiation doses, γ, were degraded by glycolysis, which resulted in an increased yield of bis(2‐hydroxyethyl) terephthalate (BHET) monomer. The XPS analysis showed that the calcination temperature of the catalyst, T, affects the strength of the acid and/or basic sites of catalyst, degradation products, and reaction time. The NH3‐temperature‐programmed desorption (TPD) analysis showed the interaction between TiO2 and Pt led to a wide distribution of middle strength acid sites. Processing of PET by gamma irradiation showed that the average molecular weight of degradation products and reaction time decreased by increasing gamma dose. The composition (wt%) analysis indicated that the highest values of yield and selectivity of BHET were achieved in the optimum values of γ = 70 kGy and T = 450°C. The proposed procedure helps to attain minimize the residual oligomers and unreacted species during PET recycling.

Gamma Radiation Detection Response of Pt/PZT/SRO Based Capacitor for Dosimetry Application

Radiation induced changes in the electrical properties of PbZrTiO3 (PZT) thin films have been studied for dosimetry application. The radiation detection was based on radiation induced changes in the electrical properties under the influence of gamma radiation. Epitaxial heterostructure of ferroelectric PbZr0.52 Ti0.48O3 (001)/SrRuO3 (SRO) were grown on single crystal SrTiO3 (001) substrates by pulsed laser deposition and platinum (Pt) electrode was deposited on top of the PZT film. The maximum capacitance of the heteroepitaxial capacitor devices was $\approx ~25$ pF with a corresponding small leakage current. The effect of gamma ( $\gamma $ -ray) irradiation on the intrinsic electrical behavior of the Lead Zirconate Titanate (PZT) capacitor devices were explored in form of the current–voltage (I–V) and capacitance–voltage (C–V) properties. The PZT devices were exposed to a 60Co Gamma source with 2.8 kGy/h dose rate from 0 kGy to 400 kGy doses. Gamma radiation induced broadening was observed in full width half maxima (FWHM) of the x-ray diffraction (00l) peak with the increasing gamma doses. All devices showed a consistence changes in conductance and capacitance with increasing gamma doses. The results demonstrated linear relationship in electrical response of PZT thin-film capacitors as a function of gamma doses. The device showed significant changes in the values of current and capacitance with the increase in dose up to 400 kGy and are therefore suitable for high-dose dosimetry applications.

Study of gamma-ray effects on relaxation oscillator based on unijunction transistor

The object of this research is all the semiconductor unijunction transistor device (UJT) parameters that affect its operation as 1.67 kHz saw-tooth relaxation oscillator circuit under the influence of gamma-irradiation dose. Relaxation oscillators are widely used in function generators, electronic beepers, inverters, blinkers, and voltage-controlled oscillators. The properties of UJTs are like those of other semiconductor devices are greatly affect by irradiation. Its electrical characteristics and the output voltage waveforms of the relaxation oscillator circuit were investigated and plotted as a function of different gamma-dose levels. The type of semiconductor, the design of the device and the type of radiation are affected the magnitude of this change. Where, it is shown that increasing gamma dose up to 3.0 MGy leads, the peak voltage (VP) to be decreased from 3.71 Volts down to 2.9 Volts, while the valley voltage (VV) to be increases from 1.54 Volts up to 1.89 Volts, leading to a pronounced narrowing on the negative resistance region. As a result, both the output signal voltage amplitude and the frequency of the relaxation oscillator circuit were shown to be functions of the gamma-irradiation dose. Where, the initial values of the output signal voltage amplitude were reported to be 2.54 Volts decreased to the value of 2.13 Volts, while its frequency was 1.67 kHz increased up to 1.85 kHz, respectively, due to gamma-exposure levels up to 3.0 MGy using the GammaCell-220 (National Center for Radiation Research and Technology of Egypt).

64Cu enrichment using the Szilard-Chalmers effect – The influence of γ-dose

Cu is an important trace metal which plays a role in many biological processes. The radioisotope 64Cu is often used to study such processes. Furthermore, 64Cu finds applications in cancer diagnostics as well as therapy. For all of these applications 64Cu having high specific activity is needed. 64Cu can be produced in cyclotrons or in nuclear reactors. In this paper we study the effect of gamma dose on the production of 64Cu according to the Szilard-Chalmers reaction using Cu(II)-phthalocyanine as a target. For this purpose, irradiations were performed in the nuclear reactor of the Delft University of Technology using a novel irradiation facility helping to limit the dose produced by gammas present in the reactor pool. The obtained 64Cu activity yield was in general above 60% in accordance to the theoretical expected value. An increase in gamma dose has no significant influence on the obtained activity yield but increases the loss of Cu from Cu(II)-phthalocyanine up to 0.9% and hence decreases the specific activity that can be obtained. However, without optimisation, when reducing the gamma dose specific activities in the order of 30 TBq/g can be achieved.

Structural Features and Photoelectric Properties of Si-Doped GaAs under Gamma Irradiation.

GaAs has been demonstrated to be a promising material for manufacturing semiconductor light-emitting devices and integrated circuits. It has been widely used in the field of aerospace, due to its high electron mobility and wide band gap. In this study, the structural and photoelectric characteristics of Si-doped GaAs under different gamma irradiation doses (0, 0.1, 1 and 10 KGy) are investigated. Surface morphology studies show roughen of the surface with irradiation. Appearance of transverse-optical (TO) phonon mode and blueshift of TO peak reflect the presence of internal strain with irradiation. The average strain has been measured to be 0.009 by Raman spectroscopy, indicating that the irradiated zone still has a good crystallinity even at a dose of 10 KGy. Photoluminescence intensity is increased by about 60% under 10 KGy gamma irradiation due to the strain suppression of nonradiative recombination centers. Furthermore, the current of Si-doped GaAs is reduced at 3V bias with the increasing gamma dose. This study demonstrates that the Si-doped GaAs has good radiation resistance under gamma irradiation, and appropriate level of gamma irradiation can be used to enhance the luminescence property of Si-doped GaAs.

Physicochemical properties of colloidal Ag/PVA nanoparticles synthesized by gamma irradiation

Silver nanoparticles (Ag NPs) are widely studied because of their superior properties so they are extensively used in various applications. Structural modification with the right synthesis method is the key to obtain superior properties of Ag NPs. In this experiment, gamma irradiation methods have been used to synthesize Ag NPs. The synthesis solution was prepared from a solution of silver metal nitrate salts with a molarity of 10 mM and then mixed in a polyvinyl alcohol (PVA) solution. The irradiation process was carried out in the Cobalt-60 gamma source chamber at a range dose from 0 to 10 kGy with a dose rate of 4.6 kGy/h. This process has caused the solution turns to yellow indicating the formation of Ag/PVA colloidal nanoparticles. The Ag/PVA nanoparticles were characterized using UV-Vis spectrophotometer and Transmission Electron Microscopy. The UV-Vis spectra showed the localized surface plasmon resonance at wavelengths of 420-407 nm. The intensity of the absorption peak increases with increasing gamma dose and reaches a maximum value starting at a dose of 4 kGy. The TEM images showed the shape of Ag NPs is spherical with an average particle size getting bigger with increasing irradiation dose.

Effect of gamma irradiation on seed germination and plant growth parameters of three rice varieties cultivated in Sri Lanka

Development of rice varieties using induced mutation has seldom been applied in Sri Lanka. This study was carried out to determine the effect of gamma irradiation doses on seed germination and different plant growth parameters of three rice varieties in Sri Lanka. Two hundred grams of seeds of three rice varieties (Bg 94–1, Bg 1165–6, Suwandal) were irradiated varying doses of 200, 300 and 400 Gy using 60Co Gamma Cell Irradiator facility at the International Atomic Energy Agency (IAEA) laboratories Seibersdorf, Austria. The experiment was designed as split plot with three replications and conducted at the plant house of Rice Research and Development Institute, Batalagoda. The effects of gamma irradiation on seed germination and different plant growth parameters were evaluated (radio sensitivity testing). With the increase in gamma doses, seed germination, seedling emergence, seedling height, root length, and plant survival in the field were declined. Significant (P<0.05) differences were observed between different varieties in seedling height, root length and percentage of field survival. Gamma irradiation showed significant (P<0.05) negative correlation with seed germination (–0.52), seedling emergence (–0.54), seedling height (–0.54), root length (–0.50) and field survival (–0.42). Percentage of survival in the field was the least affected while the percentage reduction was 8.56. The most efficient and optimum dose to induce rice mutation of the varieties under investigation is within the range of 200 – 300 Gy. More pronounced adverse effect was observed for all the growth characters at the highest dose in all three varieties. Increasing doses above 400 Gy caused severe morphological damages to the rice plants and increased doses of gamma irradiation have a negative correlation with germination and other parameters of plant growth. A comprehensive study should be carried out to determine the optimum doses for different rice varieties that could be useful in rice varietal improvement programmes in Sri Lanka.

Influence of gamma radiation on the optical, morphological, structural and electrical properties of electrodeposited lead selenide nanowires

The influence of gamma radiation exposure is studied on the optical, morphology, structural and electrical properties of PbSe nanowires with 100 nm diameter. The PbSe nanowires are synthesized by template-based electrodeposition technique. Samples are exposed using Co60 gamma source at different doses. Gamma radiation is electromagnetic radiation with high energy, frequency and penetrating power. Gamma radiations at precise doses can tune the physical properties of PbSe nanowires as infrared detectors for various applications. The optical study was carried out using UV–Vis NIR spectroscopy in reflectance mode. Further, the optical parameters such as bandgap, refractive index, static and high-frequency dielectric constant were calculated for pristine and gamma radiation exposed PbSe nanowires. The bandgap as calculated from Kubelka-Munk function decreased from 0.74 eV to 0.60 eV with an increase in dose from pristine to 200 kGy. The morphology of the nanowires was recorded using scanning electron microscopy. The nanowires obtained are cylindrical in shape and uniform throughout the length. The detailed analysis of the structural properties of PbSe nanowires is done using Scherrer and W–H methods. The preferred orientation of planes was determined by texture coefficient analysis. Strain, stress and energy density is calculated for the most preferred plane as obtained in texture coefficient (TC) analysis. The I–V characteristics is calculated before and after gamma exposure. In Raman spectra, the evolution of 2LO vibrational mode was observed with an increase in gamma radiation dose. The I–V characteristics represent space-charge limited conduction (SCLC) behaviour and an increase in current with increase in gamma dose for PbSe nanowires which makes it important for various potential applications in optoelectronic devices.

Gamma irradiation effect towards photoluminescence and optical properties of Makrofol DE 6-2

The optical, Raman and Photoluminescence properties of Makrofol DE 6-2 polycarbonates were explored in detail. A set of polymeric Makrofol samples were subjected to γ-ray source at various doses ranging between 1 and 200 kGy. UV–Vis spectra depicted that Makrofol DE 6-2 has a high absorption maximum band at about 230 nm and decreases sharply at about 285 nm. The optical energy band gap was calculated using different methods, Ineffective Thickness Method (ITM), Derivation of Ineffective Thickness Method (DITM), Absorption Spectrum Fitting (ASF) and Derivation of Absorption Spectrum Fitting (DASF) methods. All used methods revealed an observable decrease in the optical energy band gap values with increasing gamma irradiation doses for both the indirect and direct transitions, whereas the refractive index showed the reverse trend. Also, the photoluminescence intensity decreases with increasing gamma dose up to 200 kGy due to formation of defects. Peaks at 884, 1364, 1394 and 1854 cm−1 are registered corroborative its structure in the Raman spectrum. Its intensity showed a decrease with increasing the gamma dose which may be attributed to the formation of non-irradiative levels as a result of degradation. Color change of the polymer from transparent to faint yellowish after γ-irradiation of doses higher than 1 kGy was observed which may be due to formation of color centers appeared in the range 305–315 nm. The present results should be taken into account before utilization of Makrofol DE 6–2 in photoelectric devices and medical applications related to gamma radiation.

Tm-Tstop analysis and dosimetric properties of Ce doped BaB4O7 phosphor

In this work, the study on gamma ray exposed Thermoluminescence (TL) response in the range 1 Gy–3 kGy has been carried out on BaB4O7:Ce phosphor. Optimization of Ce doping concentrations in BaB4O7 phosphor was done by varying the Ce concentration from 0.5 to 3 mol %. A facile solid-state diffusion method was used to synthesize the phosphor material. Structural and morphological properties were studied using X-ray diffraction spectroscopy (XRD) and scanning electron microscopy (SEM), respectively, which revealed its monoclinic crystal structure and average particle size of ∼2 μm was observed. Optical characterization was carried out using photoluminescence (PL), which shows a blue color emission band, with maximum intensity at ∼ 450 nm and ∼500 nm. In dosimetric studies, two main peaks in the TL glow curve were observed at 176 °C and 311 °C. The intensities of these peaks found to be increasing linearly with an increase in gamma doses. To know about trap levels, the TL glow curve study was carried out through the activation energy -Tstop method in combination with the Initial Rise Method (IRM). The trapping parameters, Order of kinetics, frequency factor, and Figure of Merit were obtained by Glow Curve Deconvolution (GCD) method. The efficient thermoluminescent properties of BaB4O7:Ce phosphor makes them promising dosimetric phosphor material and provides a gateway for potential medical and radiation dosimetric applications.

Gamma dose dependent structural, optical and current-voltage characteristics of CdS/p-Si heterojunction

Heterojunction of CdS/p-Si were fabricated by deposited the cadmium sulfide (CdS) thin films on p-type silicon (Si) substrates using successive ionic layer adsorption and reaction (SILAR). To study the nano-structural, optical and current–voltage (I–V) characterization, the heterojunction was irradiated by gamma radiation with different dose in the range of 0–100 kGy. The X-ray diffraction results showed that CdS thin film has a nano-crystalline hexagonal structural with reduction in crystallinity. An increase in gamma irradiation dose the deposition temperature enhances crystallite sizes of CdS thin film. Field emission scanning electron microscope represented that the grain size was increased with increasing the gamma irradiation dose. The diffuse reflectance indicated that the CdS thin energy band gap shifted to lower energy as of function of gamma dose. The electrical parameters were calculated from the I–V characterization carried out in dark at room temperatures. From these measurements it is inferred that the forward current increases with increasing gamma dose whereas the turn on voltage drops from 4.38 V to 3.64 V. The ideality factor of the n-CdS/p-Si heterojunction is greater than unity, whereas the optimized values of series resistance, barrier height and saturation current for the CdS/p-Si changed with radiation because of density of defect induced by gamma and charge carrier trapping on interface layer.

Gamma irradiation dose dependent nano-structural, optical and impedance spectroscopy of PdS thin films

Gamma irradiation is recognized to modify the properties of thin films. In the present work, the effects of gamma irradiation on the nano-structural electrical and optical properties as of function of radiation dose has been studied. The PdS thin films deposited on glass substrate by successive ion layer adsorption and reaction (SILAR). The deposited thin films were irradiated by the gamma radiation with the 60Co for the Gamma dose range from 0 to 100 kGy. As deposited and gamma irradiated PdS thin films were investigated by impedance spectroscopy, X-ray diffraction, energy dispersive X-ray, scanning electron microscopy and Photoluminescence. The X-ray diffraction patterns exhibited a tetragonal structure of PdS thin films before after gamma irradiation, and demonstrated the changes in crystallinity, dislocation density, crystallite size and micro-strain. Field emission scanning electron microscopy and energy dispersive X-ray study conformed atomic composition of PdS thin film (1:1 ratio of Pd:S) and revealed that shape and size of grain depend on dose of gamma irradiation. Photoluminescence peak are found to be shifted to longer wavelength, intensity and width of photoluminescence peak increased for the gamma irradiated samples with increasing gamma dose. Impedance spectroscopy revealed that the enhancement of charge carrier density of irradiated PdS thin films increased linearly with gamma dose. The achieved results prove that gamma irradiation has superficial influence on nano-structural, optical and electrical properties of the deposited PdS thin films.

Non-linear structural and surface morphological modifications due to gamma irradiation in p-type porous silicon

The effect of gamma irradiation on the morphology and electrical properties of p-type porous silicon prepared by electro-chemical etching is investigated after total irradiation dose of 0.5Gy, 2Gy, 5Gy and 10Gy by gamma radiation from the 137Cs radiation source. Structural changes are studied with the support of X-Ray Diffraction, Scanning Electron Microscope, Fourier Transform Infra-Red spectroscopy, Atomic Force Microscope and the electrical property changes are investigated by I–V characterization. X-Ray Diffraction peak at Si(400) showed peak broadening with increasing gamma dose. The size of crystallite in the PSi samples as prepared is 119.54 nm and it is reduced to 14.79 nm for the PSi sample irradiated with the gamma dose of 10 Gy. The irradiated PSi samples show a non-linear reduction in crystallite size and exhibit radiation hardness for the total gamma irradiation dose ≤ 5Gy. Scanning Electron Microscope images of the irradiated PSi revealed a wide variation in pore diameter from 14.794 nm to 105.324 nm for the gamma dose increased from 0.5 Gy to 10 Gy. Roughness in the irradiated sample decreased with increase in gamma dose. The change in the structural properties of the irradiated PSi samples is nonlinear while the electrical property is linear with the increase of gamma dose and dependent on the total gamma dose.

Influence of mono energetic gamma radiation on structural and electrical properties of TiO2 thin film coated on p-type porous silicon

Titanium dioxide thin film was coated on p-type porous silicon by sol–gel spin coating method. The prepared samples were irradiated by the mono-energetic gamma radiation at Auto-irradiation facility with the Cesium-137 for the Gamma dose range from 100 to 1000 mSv. Gamma irradiated samples revealed that the physical changes of titanium oxide/porous silicon layer found to be varying with increasing gamma dose. The irradiated titanium oxide/porous silicon layer were investigated by scanning electron microscopy, X-ray diffraction, Fourier transform infra-red, Photoluminescence and I–V characteristics studies. The surface morphology of the irradiated titanium oxide/porous silicon layer has shown deformation with increasing gamma dose. The X-ray diffraction patterns of titanium oxide/porous silicon layer after irradiation revealed changes in crystallite size, dislocation density, strain and phase content. These changes in anatase (004) are linear with gamma dose than the rutile (310) of TiO2-PSi. Fourier transform infra-red spectrums of the irradiated samples showed an increase in intensity of vibration modes with the increase of the radiation dose. Photoluminescence peaks are found to be in the range of 330 to 360 nm for all the irradiated samples and the intensity of Photoluminescence peak increased for the irradiated samples with increasing gamma dose. I–V Characteristics revealed that the electrical conductivity of irradiated samples increased linearly with gamma dose. The linear changes in electrical property of titanium oxide/porous silicon under the influence of mono-energetic gamma photons gives a positive indication that it can be further studied for the development of radiation sensor for applications in nuclear field.

Improvement in Optical Properties of Nuclear Track Detector

The purpose of this work was obtaining information about the interaction of γ- ray with CR-39 track detector by using the UV-Vis spectrometry and FTIR which can be used in concerning sensor for gamma irradiation. CR-39 samples irradiated by radioactive source Co-60 at different doses are (0, 100, 200, 300, 400, and 500 kGy). The UV-Vis spectroscopy show transitions electronic in the visible region from ground state to excited state, by increasing gamma doses, and the absorbance spectrum for all samples take the same behavior with slightly shift. This shift due to decrease in the optical band gap energy E_g. The FTIR spectra show for all samples there are increases in the intensity of the characteristic peaks with increasing gamma ray, at 3234, 2367 and 1817 cm^-1, this increase may be related to more oxidation process that, in turn was produced on the polymer chains by increase gamma doses, and the number of peaks at 1817, 2367, 2645 and 3234 cm^-1 is belong to carbonate group C=O stretching vibration, O=C=O asymmetric by stretching, C-H Stretching, H₂O free stretching vibration, respectively. By increase gamma ray did not observed changes in the CR-39 groups but observed change in the intensities of peaks, then CR-39 detector can be used properly in the field of radiation dosimetery.

Effects of high dose gamma irradiation on the optical properties of Eu3+ doped zinc sodium bismuth borate glasses for red LEDs

Interaction of 10ZnO-5Na2O-10Bi2O3–74.3B2O3-0.7Eu2O3 glasses exposed to high dose gamma rays were investigated using XRD, FTIR, absorption, photoluminescence followed by thermally and optically stimulated luminescence studies. XRD analysis confirmed the amorphous nature of glasses post-irradiation. Variation in FTIR spectra revealed, structural deformation of borate groups as a result of high dose gamma irradiation. Enhanced glass absorbance and red shift in absorption edge were observed with the increase in gamma dose. Further, radiation-induced absorption coefficient confirmed the trapped charges in the forbidden energy gap supported by Tauc's plot and Urbach energy. Photoluminescence (PL) study demonstrated quenching of luminescence intensity at higher gamma doses. Lifetime of metastable 5D0 state of Eu3+ ions were estimated by the decay curves and color purity was calculated using 1931 CIE chromaticity coordinates (x,y). Thermally and optically stimulated luminescence studies reassured the existence of charges in trap centers due to irradiation. TL glow curve exhibited two broad emission peaks with the corresponding temperature being at 490 K and 625 K. Distinct TL peaks of the material and their kinetic parameters (E, S, τ and b) were determined via Computerized Glow Curve Deconvolution (CGCD) method. Linear behaviour obtained through the dose response of the glass (0.25–3 kGy) proved their suitability for dosimetric application in the food irradiation zones in addition to red LEDs (< 1 kGy).

Impact of gamma irradiation on the development and reproduction of Culex pipiens (Diptera; Culicidae)

Purpose: The aim was to evaluate the effects of irradiation of Culex pipiens irradiated as pupae on the larval and pupal mortality percentages, the larval and pupal duration, adult emergence percentages and ovarian development in comparison with the un-irradiated group.Material and methods: The mosquito, C. pipiens Linnaeus (L) was irradiated as pupae with three gamma doses 40, 60 and 80 Gy. Different biological aspects include the ovarian development of irradiated females tested.Results: Gamma doses used significantly increased the larval and pupal mortality percentages, the larval and pupal duration and significantly decreased the adult emergence percentages. Moreover, fecundity and egg hatchability percentages were severely decreased with increasing gamma doses. While the sterility% was positively correlated with the doses used. Gamma doses caused a dose-dependent decrease in the number of developed eggs, reduction in the number of developed oocytes, signs of degenerative processes in oocytes, yolk mass and egg size decrease.Conclusions: Results obtained indicated that gamma radiation of C. pipiens induced remarkable effects on the biological, developmental and reproductive activity.