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Graphene aerogels (GAs) are of significant interest in the scientific community due to their unique attributes, including a three-dimensional porous structure, exceptional specific surface area, and remarkable chemical stability. Researchers have made notable breakthroughs in aerogel preparation, focusing on aspects like porous structures and chemical stability. This review explores product morphologies and properties developed between 2011 and 2023, particularly examining applications of graphene aerogels with amine or alcohol radical scavengers. It offers a roadmap for researchers, suggesting possibilities for radiation-based preparation and indicating broader applications. These findings contribute to a deeper understanding of aerogels and expand the potential applications of graphene aerogels across various fields. [ABSTRACT FROM AUTHOR]

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In this study, self-doping defects were introduced to optimize the interlayer spacing and pore structure of hard carbon by γ-ray irradiation. The effects of the absorbed dose on the interlayer spacing, internal defects, and disordered structure of hard carbon were investigated through scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, and isothermal nitrogen adsorption/desorption. The electrochemical properties were investigated using the constant current charge-discharge. The results showed that the surface crystallinity and disordered structure of hard carbon increased with the absorbed dose. Moreover, the electrochemical properties of hard carbon were clearly improved. At a dose of 140 kGy, hard carbon presented a high specific surface area of 425.343 m2/g and provided a sodium storage capacity of 300 mAh/g at 30 mA/g; the high current density capacity remained at 195 mAh/g at 1 A/g, suggesting that the electrode capacity increased three-fold. Excellent stability was also maintained during high-rate charge-discharge. This work provides new approaches and ideas for the design of advanced nanomaterials and defect engineering applications in the field of energy storage.

Graphene aerogels (GAs) are of significant interest in the scientific community due to their unique attributes, including a three-dimensional porous structure, exceptional specific surface area, and remarkable chemical stability. Researchers have made notable breakthroughs in aerogel preparation, focusing on aspects like porous structures and chemical stability. This review explores product morphologies and properties developed between 2011 and 2023, particularly examining applications of graphene aerogels with amine or alcohol radical scavengers. It offers a roadmap for researchers, suggesting possibilities for radiation-based preparation and indicating broader applications. These findings contribute to a deeper understanding of aerogels and expand the potential applications of graphene aerogels across various fields.

Ultra‐high molecular weight polyethylene (UHMWPE)/illite‐smectite interstratified clay minerals (ISIC) composites were irradiated by γ‐ray in air and N2 at 75 kGy. The abrasion‐resistance of composites were studied via a ring‐on‐ring friction tester under dry friction conditions. Compared with virgin UHMWPE, the friction coefficient and wear rate of UHMWPE filled with 0.5 wt% ISIC powders and irradiated by γ‐ray in N2 could be further reduced by near 3.1% and 88.0%, respectively. The worn surfaces of the UHMWPE/ISIC composites irradiated in N2 were relatively smooth after dry friction. The composites exhibited relatively high wear resistance. ISIC powders can play the role of heterogeneous nucleation and induce the crystallization of UHMWPE, thereby improving the abrasion‐resistance. The linear molecular chain of UHMWPE was transformed into a three‐dimensional crosslinked structure after irradiation, which can effectively enhance the plastic deformation resistance and then improve the tribological properties. The results show that low filling amount of ISIC powders and γ‐ray irradiation in N2 are effective strategies to improve abrasion resistance of UHMWPE. [ABSTRACT FROM AUTHOR]

Intramolecular crosslinking of polyvinylidene fluoride (PVDF) was observed to have occurred when the PVDF homogeneous solution was subject to γ-ray irradiation, which was confirmed by characterization of PVDF before and after irradiation via FTIR, the thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), gel permeation chromatography (GPC), viscosity measurement and small-angle X-ray scattering (SAXS). This constitutes a contrast to the frequent occurrence of intermolecular crosslinking that takes place when PVDF is irradiated in a solid state. Such a finding increases our understanding of the radiation effects of polymers. Based on the experimental results, a possible crosslinking mechanism is also proposed. [ABSTRACT FROM AUTHOR]

Purpose: Ionizing radiation has been used for developing new cultivars of diverse plant species, including Cymbidium orchid species. The effects of the total dose on mutation induction have been investigated; however, there is relatively little research on the influence of the dose rate or irradiation duration. Materials and methods: Thus, we analyzed the effects of the total dose and irradiation duration on the growth of Cymbidium hybrid RB001 protocorm-like bodies (PLBs). We completed a genotyping-by-sequencing analysis to compare the induced SNPs among five γ-irradiated populations with similar growth responses (LD50) to γ-rays. Results: The optimal time to assess the effects of the γ-irradiation was at 6 months after the treatment. On the basis of the survival rate of γ-irradiated PLBs, the optimal doses (LD50) for each irradiation duration were estimated: 1 h, 16.1 Gy; 4 h, 23.6 Gy; 8 h, 37.9 Gy; 16 h, 37.9 Gy; and 24 h, 40.0 Gy. The estimated optimal doses were duration-dependent at irradiation durations shorter than 8 h, but not at irradiation durations exceeding 8 h. A SNP comparison revealed a lack of significant differences among the mutations induced by γ-irradiations. Conclusions: These results indicate the irradiation duration affects PLB growth in response to γ-rays. Moreover, the mutations induced by a short-term treatment may be similar to those induced by a treatment over a longer period. [ABSTRACT FROM AUTHOR]

• Deuterium permeation under γ-ray irradiation through ceramic coatings was measured. • Deuterium permeation in ceramic coatings increased during irradiation at 250–300 °C. • γ-ray irradiation effect decreased with crystallization of ceramic coatings. • Ceramic coatings reduced deuterium permeation as well as γ-ray irradiation effect. γ-ray irradiation effect on deuterium permeation through three kinds of ceramic coatings with different crystal structures has been investigated. Deuterium permeation flux through the coatings increased during γ-ray irradiation at 250–300 °C, but changes in the permeation flux were not detected at above 300 °C. The permeation flux through an erbium oxide coating increased due to crack formation during a permeation experiment at 500 °C. After deterioration of the coating, the γ-ray irradiation effect on permeation through the coating was similar to that of reduced activation ferritic/martensitic steel F82H substrate. On the other hand, an yttrium oxide coating had an amorphous structure and started crystallization at 500 °C. Although the irradiation effect before the crystallization was derived from the F82H substrate, the effect derived from the coating was detected after crystallization because the rate-determining process of permeation shifted to the coating. Compared to the results at 300 °C before and after crystallization, the irradiation effect decreased, proving that the ceramic coatings reduced the deuterium permeation as well as the γ-ray irradiation effect. [ABSTRACT FROM AUTHOR]

Tritium handling in fusion reactors is important for economical fuel cycles and radiological safety; however, the extremely limited number of studies on tritium permeation through structural materials under irradiation conditions has been reported. In this study, γ-ray irradiation effect on tritium permeation has been investigated using three kinds of metals with different permeation properties including palladium, platinum, and austenitic stainless steel. An increase of deuterium signal on the quadrupole mass spectrometer during irradiation consisted of an increase of deuterium permeation flux and an electrical noise, and both were separately detected. The increase rate of permeation flux for all materials became lower as the test temperature increased. Dose rate dependence of the increase rate was confirmed. Oxidation of the austenitic stainless steel indicates a decrease of not only the deuterium permeation flux but also the irradiation effect. [ABSTRACT FROM AUTHOR]

In this study, maize starch treated with γ radiation (0–10 kGy) was used to prepare maize granular starch-ascorbyl palmitate (MGS-AP) complexes by a hydrothermal method. The MGS-AP complex encapsulation efficiency and physicochemical properties were evaluated. The irradiation effect on starch chain degradation increased the percentage of ascorbyl palmitate (AP) encapsulated in the starch and considerably raised the Rapid Visco Analyzer (RVA) profile viscosity in the later cooling stage. With increasing irradiation dose, the MGS-AP complex swelling power, relative crystallinity and thermal stability gradually increased, and the antioxidation activity first decreased and then increased, with a minimum value at 1 kGy. Generally, the MGS-AP complexes had relatively high encapsulation efficiencies, and a complex with the highest swelling power, crystallinity, shearing resistance, antioxidation activity and thermal stability was obtained with 10 kGy irradiation. This study provides a basis for preparing granular starch-AP complexes with a relatively high encapsulation efficiency and stability. • An irradiation-hydrothermal method was used to prepare MGS-AP complexes. • Encapsulation efficiency of MGS-AP complexes increased after irradiation. • The RVA profile of the complex in the later cooling stage shifted with irradiation. • Swelling power and thermostability of the complex increased with irradiation dose. • The complex with an irradiation dose of 10 kGy had the highest antioxidant activity. [ABSTRACT FROM AUTHOR]

High purity fused silica samples have been irradiated by 60 Co γ-ray at the doses of 50, 500 and 5000 kGy, and the effect of γ-ray irradiation on the optical property and laser damage performance of silica have been investigated. After γ-ray irradiation, there is no obvious change on the surface of silica observed. However, the surface roughness increases slightly with increasing γ-ray irradiation dose. When the irradiation dose reached 500 kGy and above, a broad absorption band at 215 nm, ascribed to E′ color center, is significantly observed and its intensity increases greatly with increasing dose. After laser irradiation, the distribution of laser induced damage threshold (LIDT) is related to γ-ray dose, and the LIDT decreases monotonously with increasing dose. A mechanism for the degradation of laser damage resistance is presented. [ABSTRACT FROM AUTHOR]

AtTDX, a thioredoxin-like plant-specific protein present in Arabidospis is a thermo-stable and multi-functional enzyme. This enzyme is known to act as a thioredoxin and as a molecular chaperone depending upon its oligomeric status. The present study examines the effects of γ-irradiation on the structural and functional changes of AtTDX. Holdase chaperone activity of AtTDX was increased and reached a maximum at 10 kGy of γ-irradiation and declined subsequently in a dose-dependent manner, together with no effect on foldase chaperone activity. However, thioredoxin activity decreased gradually with increasing irradiation. Electrophoresis and size exclusion chromatography analysis showed that AtTDX had a tendency to form high molecular weight (HMW) complexes after γ-irradiation and γ-ray-induced HMW complexes were tightly associated with a holdase chaperone activity. The hydrophobicity of AtTDX increased with an increase in irradiation dose till 20 kGy and thereafter decreased further. Analysis of the secondary structures of AtTDX using far UV-circular dichroism spectra revealed that the irradiation remarkably increased the exposure of β-sheets and random coils with a dramatic decrease in α-helices and turn elements in a dose-dependent manner. The data of the present study suggest that γ-irradiation may be a useful tool for increasing holdase chaperone activity without adversely affecting foldase chaperone activity of thioredoxin-like proteins. [ABSTRACT FROM AUTHOR]

Silk fibroin fiber from Bombyx mori has the advantages of superior tensile strength, non-toxicity, and good biocompatibility. However, its dense crystal structure makes implanted silk fibroin fiber resistant to biodegradation in the body. In the work described herein, silk fibroin fiber was treated with nine different dosages (0−3000 kGy) of Cobalt-60 (60Co) γ-rays, and the degradation performances of the irradiated silk fibroin fibers in collagenase IA (digestion for 30 days) were investigated. The results showed that the degradation leaching rate increased by 25, 35, and 58% at doses of 100, 200, and 500 kGy, respectively, and the diameter was about 62−65% compared with that in the control group. At a dose of 100 kGy, clear degradation stripes appeared on the surface of the silk fibroin fibers, and significantly increased at a dose of 200 kGy. With further increases of 60Co dose, the stripes deepened and turned into cracks. Degradation increased in the amorphous regions of silk fibroin fiber after treatment with γ-rays. With increasing doses of 60Co, degradation also occurred in crystalline areas and the silk II structure was partly converted into silk I. Our studies have shown that appropriate doses (such as 30−500 kGy) of γ-ray pre-treatment on silk fibroin fiber can promote its biological degradation. [ABSTRACT FROM PUBLISHER]

Abstract: Chitosan from squid pens with deacetylation degree (DD) of 70% and average molecular weight (M w0) 90.5×103 in dilute lactic acid solution containing H2O2 (1%) was effectively degraded by irradiation with gamma 60Co radiation (1.33kGy/h) at doses in the range 4–16kGy. Based on the results of M w measured by gel permeation chromatography (GPC), it was concluded that there was particularly strong synergy between H2O2 and radiation for degradation at the lower radiation doses studied. Radiation scission yields (Gs) were found out to be 2.2μmol/J and 0.2μmol/J for 5% chitosan with and without 1% H2O2, respectively. The DD of degraded chitosan measured from IR spectra was almost unchanged by the treatment. [Copyright &y& Elsevier]

This in vitro study evaluated the detrimental effect of acute gamma (γ)-irradiation on rat immature hippocampal neurons . Rat immatur e hippocampal neurons (0.5 day in vitro) were irradiated with 0~4 Gy γ-rays. Cytotoxicity was analyzed using a lactate dehydrogenase release assay at 24 h after γ-irradiation. Radiation-induced cytotoxicity in immature hippocampal neurons increased in a dose- dependent manner. Pre-treatments of pro-apoptotic caspase inhibitors and anti-oxidative substances significantly blocked γ-irradiation-induced cytotoxicity in immature hippocampal neurons. The results suggest that the caspase-dependent cytotoxicity of γ-rays in immature hippocampal cultured neurons may be caused by oxidative stress. [ABSTRACT FROM AUTHOR]

Abstract: The technology of high-energy irradiation is widely used in the field of material interface modification because of its high efficiency, energy conservation and environment friendliness. In this paper, γ-ray irradiation graft technology was used in order to enhance the surface performance of the carbon fibre (CF). The surface chemical elements and functional groups of untreated and irradiated CF were observed by photoelectron spectroscopy (XPS). The results show that the value of O/C and the quantity of oxygen functional groups on CF surface were enhanced efficiently after treatment by γ-ray irradiation graft technology. The morphology of CF was characterized by scanning electron microscopy (SEM) and atom forced microscopy (AFM), respectively. The surface roughness of CF was greatly increased compared with the untreated CF. Moreover, the interface performance was clearly improved after irradiation. [Copyright &y& Elsevier]

Abstract: In this study, locally produced chitosan powder was irradiated with pre-determined doses of γ-ray (Co-60) of 10 kGy, 25 kGy, 50 kGy and 100 kGy respectively. The properties of both chitosan powder and the chitosan film were examined and compared with unradiated chitosan. Physical characteristic of the irradiated powder and film was studied using stereo microscope. It was observed that the γ-ray induces a noticeable colour tone intensity change to the chitosan. Further investigation using Fourier Transformed Infrared Spectroscopy (FT-IR) analysis has confirmed that the chain scission reaction was occurred as a result of γ-ray exposure through the depolymerization mechanisms. Interestingly, the degree of deacetylation (DD) of chitosan measured using FT-IR showed a negligible effect due to the exposure of γ-ray radiation. Further investigation on the viscosity average molecular weight (M v) showed a reduction of M v from 577 kD of pure chitosan to 458 kD, 242 kD, 159 kD and 106 kD for 10 kGy, 25 kGy, 50 kGy and 100 kGy of γ-radiated chitosan respectively. In addition, the tensile strength and elongation at break showed a similar decreasing trend with increasing dosage of γ-ray. [Copyright &y& Elsevier]

Abstract: Free radicals are formed upon irradiation of polymers. The annealing of γ-ray irradiated syndiotactic polystyrene (sPS) with doses 10, 23 and 36kGy was studied with electron paramagnetic resonance (EPR) spectroscopy. The EPR spectra are possibly attributed to three types of radicals, (a) the benzyl radical Ra, (b) resonance structure of the phenyl radical Rb, and (c) carbon-superoxide-centered radical Rc with three-, four-, and single-line features, respectively. Radical Ra can be easily formed by the removal of the proton from the tertiary carbon; radical Rb is created from delocalization of the spin of the radical Ra onto the benzene ring; and radical Rc may be generated from the interaction of a carbon-centered radical with dioxygen from the air which forms a carbon-superoxide center. By comparing EPR spectra of the radicals with a DPPH standard, the spin numbers of the radicals can be calculated. The spin number of all radicals decreases exponentially with time in the temperature range of 60–90°C regardless of dose of the irradiation. The annealing of Ra, Rb, and Rc follows first-order kinetics. The activation energies of the annihilation are determined to be 15.8–19.0, 16.0–19.5, and 23.2–26.6kJ/mol for radicals Ra, Rb, and Rc, respectively. The kinetic study presented herein can serve as a criterion for γ-ray irradiation process in various applications, such as sterilization of polymer materials and devices. [Copyright &y& Elsevier]

Abstract: This work reports experimental results of an effort undertaken to identify and characterize the radiation-induced defects created during gamma (γ)-irradiation of commercial glass on the basis of optical absorption measurements performed before and after irradiation. It is assumed that the induced absorption band formed after γ-irradiation of soda-lime-silica (SLS) glasses are created by some hole-type color centers related with non-bridging oxygen ions (NBO−) located in different surroundings. Results have been discussed taking into consideration the presence of iron as impurity in the glass structure. It is well known that the absorption bands of Fe3+ in the visible range is at 420–440nm, in this study the band at 430nm was followed. Also, the optical gap variations (ΔE opt) induced by γ-irradiation were investigated. Moreover, the study illustrated that the optical absorption sensitivity and the mechanism of fading either at room or elevated temperature has been discussed in relation to successive irradiation doses, dose rate and thickness. The results are discussed on the basis of the annihilation mechanisms of induced irradiation defects. [Copyright &y& Elsevier]

Purpose: To clarify the radiosensitivity of intratumor quiescent cells in vivo to accelerated carbon ion beams and reactor neutron beams. Methods and Materials: Squamous cell carcinoma VII tumor-bearing mice were continuously given 5-bromo-2′-deoxyuridine to label all intratumor proliferating cells. Next, they received accelerated carbon ion or γ-ray high-dose-rate (HDR) or reduced-dose-rate (RDR) irradiation. Other tumor-bearing mice received reactor thermal or epithermal neutrons with RDR irradiation. Immediately after HDR and RDR irradiation or 12 h after HDR irradiation, the response of quiescent cells was assessed in terms of the micronucleus frequency using immunofluorescence staining for 5-bromo-2′-deoxyuridine. The response of the total (proliferating plus quiescent) tumor cells was determined from the 5-bromo-2′-deoxyuridine nontreated tumors. Results: The difference in radiosensitivity between the total and quiescent cell populations after γ-ray irradiation was markedly reduced with reactor neutron beams or accelerated carbon ion beams, especially with a greater linear energy transfer (LET) value. Clearer repair in quiescent cells than in total cells through delayed assay or a decrease in the dose rate with γ-ray irradiation was efficiently inhibited with carbon ion beams, especially with a greater LET. With RDR irradiation, the radiosensitivity to accelerated carbon ion beams with a greater LET was almost similar to that to reactor thermal and epithermal neutron beams. Conclusion: In terms of tumor cell-killing effect as a whole, including quiescent cells, accelerated carbon ion beams, especially with greater LET values, are very useful for suppressing the dependency on the heterogeneity within solid tumors, as well as depositing the radiation dose precisely. [Copyright &y& Elsevier]

Abstract: A 137Cs γ-ray beam irradiator has been calibrated in terms of air kerma using large size chambers. The available air-kerma rates range between 1.8μGy/h (0.2mR/h) and 5.3mGy/h (0.6R/h). Large-volume chambers were used to characterize the source in terms of the radiation quantity air kerma (and exposure). Two types of chambers with significantly different characteristics and energy responses were used. This work shows that very good agreement can be obtained between the measurements performed with such different types of chambers. An agreement of 0.3% is observed between chambers even for the lowest air-kerma rates measured. [Copyright &y& Elsevier]

Abstract: Gamma-ray irradiation induced color centers and charge state recharge of impurity and doped ion in 10at.% Yb:YAP have been studied. The change in the additional absorption (AA) spectra is mainly related to the charge exchange of the impurity Fe2+, Fe3+ and Yb3+ ions. Two impurity color center bands at 255 and 313nm were attributed to Fe3+ and Fe2+ ions, respectively. The broad AA band centered at 385nm may be associated with the cation vacancies and F-type center. The transition Yb3+ →Yb2+ takes place in the process of γ-irradiation. Oxygen annealing and γ-ray irradiation lead to an opposite effect on the absorption properties of the Yb:YAP crystal. In the air annealing process, the transition Fe2+ →Fe3+ and Yb2+ →Yb3+ take place and the color centers responsible for the 385nm band was destroyed. [Copyright &y& Elsevier]

Abstract: Reduction of chromium (VI), Cr(VI) in aqueous neutral or basic solution was promoted by γ-ray irradiation in the presence of oxide particles such as TiO2, Al2O3 or SiO2. The oxide particles behaved as a catalyst, and the efficiency of the Cr(VI) reduction increased with an increase of the irradiation dose irrespective of the initial Cr(VI) concentration. The insoluble Cr(III) oxide formed through the Cr(VI) reduction also acted as the catalyst. [Copyright &y& Elsevier]

Abstract: In this study, we show that one single dose of gamma-irradiation at birth induces an inhibition of the cerebellar calcium dependent nitric oxide synthase (NOS) activity, probably correlated to the motor abnormalities and the disarrangement in the cerebellar cytoarchitecture observed in adult rats. This decrease in calcium dependent NOS activity could be associated with an increased protein kinase C (PKC) activity. PKC inhibition partially restores calcium dependent NOS activity, indicating that PKC activity could be negatively modulating the catalytic activity of calcium dependent NOS. These findings suggest that a decrease in nitric oxide (NO) production and the related increase in PKC activity could be intracellular events that participate in the onset of motor and cerebellar abnormalities induced by postnatal gamma-irradiation at early stages of life. [Copyright &y& Elsevier]

Abstract: Fifteen barbari male kids of about 3–4 months age and weighing around 10kg were randomly assigned to three groups of five animals each. The animals were used to study the effect of feeding γ-ray irradiated soybean on their growth performance, feed conversion efficiency and blood metabolites. In group I, the animals were fed soybean without irradiation treatment, and in groups II and III, the animals were fed soybean irradiated at 10 and 20kGy level, respectively. Soybean after coarsely grinding and supplementation with mineral mixture was fed to animals to meet their digestible crude protein (DCP) requirement. Animal were given ad lib berseem straw to fulfill their dry matter (DM) requirements. Data indicated that average dry matter intake (DMI) was 262.25 ± 19.21, 270.14 ± 19.23 and 273.33 ± 21.36g/day in the three experimental groups, the difference being statistically non-significant. Similarly non-significant differences due to feeding were observed in crude protein intake (CPI) digestible crude protein intake (DCPI) and total digestible nutrient intake (TDNI). Average CPI and TDNI were 50.04 ± 3.14 and 167.63 ± 10.08 in group I; 50.04 ± 3.10 and 162.23 ± 10.31 in group II; 53.53 ± 3.09 and 169.83 ± 11.77g/day in group III. Average daily body weight gain was estimated to be 33.11 ± 2.10, 35.56 ± 1.27 and 42.42 ± 2.70g/day in the three respective groups indicating the significant (P < 0.05) increase due to feeding of soybean irradiated at 20kGy. DM required per kg b.wt. gain was 7.53 ± 0.40, 7.49 ± 0.19 and 6.32 ± 0.17kg in groups I–III, respectively. The CP and TDN intake was 1.49 ± 0.09 and 4.92 ± 0.29 in group I; 1.41 ± 0.09 and 4.69 ± 0.15 in group II; 1.17 ± 0.04 and 3.96 ± 0.15 in group III for per kg gain in live weight, thus depicting significant increased efficiency of TDN utilization due to feeding of soybean irradiated at 20kGy level. Blood metabolites, i.e. glucose, cholesterol and non-esterified fatty acid (NEFA) urea and ammonia nitrogen (NH3-N)concentration was not affected significantly due to treatment. [Copyright &y& Elsevier]

Composite nanoparticles composed of noble metal (Au, Pt or Pd) and iron-oxide (Fe3O4 or γ-Fe2O3) were successfully prepared by γ-ray irradiation of a suspension of iron oxide in an aqueous solution containing noble metal. Formation of the composite nanoparticles was confirmed by the techniques of magnetic separation and XRD. TEM observation revealed that the noble metal nanoparticles were immobilized on the surface of magnetic iron-oxide nanoparticles. Aqueous dispersion of Au/γ-Fe2O3 and Au/Fe3O4 composite nanoparticles exhibited surface plasmon of Au nanoparticles. [Copyright &y& Elsevier]

We investigated sucrose radicals produced by heavy-ion irradiation with various linear energy transfer (LETs) and the possibility for a sucrose electron spin resonance (ESR) dosimeter. The impact of heavy ions on sucrose produced sucrose radicals, which were measured by ESR. The obtained spectral pattern was the same as that for helium (He) ions, carbon (C) ions, neon (Ne) ions, iron (Fe) ions, and γ-ray irradiation. Identical spectra were measured after 1 year, but the initial intensities decreased by a few percent when the samples were kept in ESR tubes with the caps at ambient temperature. The total spin concentration obtained by heavy-ion irradiation had a linear relation with the absorbed dose, and correlated logarithmically with the LET. Qualitative ESR analyses showed that the production of sucrose radicals depended on both the particle identity and the LET at the same dose. The production of spin concentration by He ions was the most sensitive to LET. Empirical relations between the LET and the spin yield for various particles imply that the LET at a certain dose can be estimated by the spin concentration. Therefore, the present ESR results imply that sucrose can be used to monitor the absorbed dose and the LET of particle irradiation. [Copyright &y& Elsevier]

This study was designed to investigate the levels of testis tissue cyclic nucleotides and plasma testosterone in testis-irradiated rats with saturation analysis 1-52 days after 676 rad and 7 days after 290-1930 rad. It was found that ionizing radiation of a given dose scale did not affect significantly the excretion of testosterone. An initial rise of cyclic adenosine monophosphate (cAMP) was probably associated with an increase of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) excretion and a decrease of cAMP in the later stage was possibly due to the depletion of the germ cells, following irradiation less than 965 rad. The reduction of cAMP after 1930 rad was probably related to direct inhibition of the larger dose of cAMP production. These results suggest that the levels of cAMP after irradiation can reflect the degree of testis radiation injury. In addition, it was also found that ionizing radiation failed to change the testis cyclic guanosine monophosphate (cGMP) levels, suggesting the presence in testis of only a 'one-way' regulation carried out by cAMP. [ABSTRACT FROM AUTHOR]

Radiolysis of chemical agents occurs during the decontamination of nuclear power plants. The γ-ray irradiation tests of the N2H4–Cu+–HNO3 solution, a decontamination agent, were performed to investigate the effect of Cu+ ion and HNO3 on N2H4 decomposition using a Co-60 high-dose irradiator. After the irradiation, the residues of N2H4 decomposition were analyzed by Ultraviolet-visible (UV) spectroscopy. NH4+ ions generated from N2H4 radiolysis were analyzed by ion chromatography. Based on the results, the decomposition mechanism of N2H4 in the N2H4–Cu+–HNO3 solution under γ-ray irradiation condition was derived. Cu+ ions form Cu+N2H4 complexes with N2H4, and then N2H4 is decomposed into intermediates. H+ ions and H● radicals generated from the reaction between H+ ion and eaq− increased the N2H4 decomposition reaction. NO3− ions promoted the N2H4 decomposition by providing additional reaction paths: (1) the reaction between NO3− ions and N2H4●+, and (2) the reaction between NO● radical, which is the radiolysis product of NO3− ion, and N2H5+. Finally, the radiolytic decomposition mechanism of N2H4 obtained in the N2H4–Cu+–HNO3 was schematically suggested. [ABSTRACT FROM AUTHOR]

• α-Fe 2 O 3 deposited porous polystyrene fiber was synthesized. • The stable micro-nano structure was formed by γ-ray method. • The photocatalytic degradation for 4-CP and 4-NP was accomplished. • Fe 2 O 3 /PS fiber showed the good stability for 6 cycling. Photocatalytic degradation by efficient and easy recyclable semiconductor-catalysts is an ideal way to solve the environmental problem. A series of Fe 2 O 3 /Polystyrene (Fe 2 O 3 /PS) composite fibers with hydrophobic property were obtained by the electrospinning and γ-Ray irradiation methods. The γ-Ray irradiation treatment not only formed steady micro-nano construction of nanoparticles and fiber, but also reduced the hydroxyl group on Fe 2 O 3 surface. The high photocatalytic efficiencies of Fe 2 O 3 /PS fiber were discovered with the high content of 4-chlorophenol (4-CP) and 4-nitrophenol (4-NP), due to the synergetic effect of adsorption and degradation. The suitable adsorption capacity of Fe 2 O 3 /PS could promote the utilization of the generated hydroxyl radical(OH) to directly oxidize the adsorbed pollutant molecules. Additionally, the photocatalytic activities for 4-CP and 4-NP still reached 80% and 75% in the 6th cycling and the composite fiber exhibited the good recyclability, which has the application development prospect for wastewater treatment. The mechanism of 4-CP and 4-NP decomposition was verified. Hence, the gained results could provide some insights into phenol degradation over the multifunctional and efficient catalyst. [ABSTRACT FROM AUTHOR]