Mn2+ induced significant improvement and robust stability of radioluminescence in Cs3Cu2I5 for high-performance nuclear battery

Fluorescent type nuclear battery consisting of scintillator and photovoltaic device enables semipermanent power source for devices working under harsh circumstances without instant energy supply. In spite of the progress of device structure design, the development of scintillators is far behind. Here, a Cs3Cu2I5: Mn scintillator showing a high light yield of ~67000 ph MeV−1 at 564 nm is presented. Doping and intrinsic features endow Cs3Cu2I5: Mn with robust thermal stability and irradiation hardness that 71% or >95% of the initial radioluminescence intensity can be maintained in an ultra-broad temperature range of 77 K-433 K or after a total irradiation dose of 2590 Gy, respectively. These superiorities allow the fabrication of efficient and stable nuclear batteries, which show an output improvement of 237% respect to the photovoltaic device without scintillator. Luminescence mechanisms including self-trapped exciton, energy transfer, and impact excitation are proposed for the anomalous dramatic radioluminescence improvement. This work will open a window for the fields of nuclear battery and radiography.

Effects of Acute and Chronic Gamma Irradiation on the Cell Biology and Physiology of Rice Plants

The response to gamma irradiation varies among plant species and is affected by the total irradiation dose and dose rate. In this study, we examined the immediate and ensuing responses to acute and chronic gamma irradiation in rice (Oryza sativa L.). Rice plants at the tillering stage were exposed to gamma rays for 8 h (acute irradiation) or 10 days (chronic irradiation), with a total irradiation dose of 100, 200, or 300 Gy. Plants exposed to gamma irradiation were then analyzed for DNA damage, oxidative stress indicators including free radical content and lipid peroxidation, radical scavenging, and antioxidant activity. The results showed that all stress indices increased immediately after exposure to both acute and chronic irradiation in a dose-dependent manner, and acute irradiation had a greater effect on plants than chronic irradiation. The photosynthetic efficiency and growth of plants measured at 10, 20, and 30 days post-irradiation decreased in irradiated plants, i.e., these two parameters were more severely affected by acute irradiation than by chronic irradiation. In contrast, acutely irradiated plants produced seeds with dramatically decreased fertility rate, and chronically irradiated plants failed to produce fertile seeds, i.e., reproduction was more severely affected by chronic irradiation than by acute irradiation. Overall, our findings suggest that acute gamma irradiation causes instantaneous and greater damage to plant physiology, whereas chronic gamma irradiation causes long-term damage, leading to reproductive failure.

Evaluation of Rats’ Spermatogenesis State under Irradiation Exposure and Influence of Natural Origin Drugs

Male infertility is probably to be affected by intense heat exposure and extreme exposure to pesticides, irradiation, electromagnetic radiation and other hazardous substances. The authors of most of the works agree that the cells of the basement membrane of the tubules and spermatogonia, which are quickly exhausted after irradiation, are the most vulnerable in the testes. The type and extent of these changes depends on the dose, duration and frequency of radiation. The participation of connective tissue in almost all typical pathological conditions has been shown: inflammation, allergy, carcinogenesis, hypoxia, free radical oxidation processes, etc. The purpose of the work was to study evaluation the state of rats' spermatogenesis under conditions of the total irradiation exposure and to correct the pathological process with drugs of natural origin Chondroitin sulfate and "Bioglobin-U". Material and methods. A model of total single irradiation with a dose of 3 Gy was used to obtain the pathology of the testes, after which the substance Chondroitin sulfate was administered at a dose of 60 mg / kg; comparison drug Tribestan at a dose of 60 mg/kg; the drug "Bioglobin-U" at a dose of 200 μl / kg and Chondroitin sulfate + Tribestan in the above doses. Results and discussion. 30 days of exposure of single total irradiation with a dose of 3 Gy led to significant disruption of the morphological state of the testes and spermatogenic epithelium of rats. Thus, in rats with irradiation, the number of normal spermatogonia in the convoluted tubules was reduced by 5.7 times, there were practically no convoluted tubules with spermatocytes in the metaphase of the 2nd maturation division (with the 12th stage of meiosis) and tubules with desquamated spermatogenic epithelium, the index of spermatogenesis decreased by almost 6.5 times. The introduction of natural origin drugs led to an improvement in the quantitative and qualitative indicators of spermatogenesis. Conclusion. In the conditions of irradiation exposure, Chondroitin sulfate has more significant regenerative properties, the effect of which is almost 1.9 times better than the effect of the reference drug Tribestan. The effectiveness of "Bioglobin-U" in these experimental conditions was somewhat inferior to Chondroitin sulfate, but this drug was almost 1.4 times more effective than the reference drug Tribestan. The combination of Tribestan and the substance Chondroitin sulfate was more than 1.4 times more effective than the reference drug Tribestan itself

Solar potential evaluation and political, economic and social analysis (PES) in the department Cesar – Colombia

This research shows the estimation of direct, diffuse and total irradiation in the department of Cesar (Colombia) through the use of the Bird and Hulstrom model and parameterizations of the Mächler and Iqbal model. The data used for this purpose were collected by the meteorological stations installed by the Institute of Hydrology, Meteorology and Environmental Studies of Colombia (IDEAM) corresponding to the range of collection and analysis with more than 20 years between 1993 and 2013, a period of study suitable for a comprehensive solarimetric study. Irradiation data were estimated taking into account four types of climate scenarios that depended on the type of atmosphere present in the study area. It was found that the solar potential of the department of Cesar, located on the Colombian Caribbean Coast, presents average total irradiations ranging from 6.2 kWh/m2day in very turbid atmospheres to 6.8 kWh/m2 day in extremely clean atmospheres, making it one of the regions with the highest irradiation values in Colombia. This panorama allows to visualize the great potential that exists in the region for the implementation of projects with both thermal and photovoltaic solar technologies. This study was also complemented with a political, economic and social analysis of Colombia compared to the United State to determine the improvement opportunities in Colombia.

Controlled Electron-Beam Synthesis of Transparent Hydrogels for Drug Delivery Applications

In this study, we highlight hydrogels prepared by electron-beam polymerization. In general, the electron-beam-polymerized hydrogels showed improved mechanical and optical transmittances compared to the conventional UV-cured hydrogels. They were more elastic and had a higher crosslinking density. Additionally, they were transparent over a broader wavelength range. The dependence of the mechanical and optical properties of the hydrogels on the number of single differential and total irradiation doses was analyzed in detail. The hydrogels were prepared for usage as a drug delivery material with methylene blue as a drug model. In the first set of experiments, methylene blue was loaded reversibly after the hydrogel synthesis. Electron-beam-polymerized hydrogels incorporated twice as much methylene blue compared to the UV-polymerized gels. Furthermore, the release of the model drug was found to depend on the crosslinking degree of the hydrogels. In addition, electron-beam polymerization enabled the irreversible binding of the drug molecules if they were mixed with monomers before polymerization.

Irradiance characteristic of a small-scale solar simulator for testing thermal collectors

This paper describes the development of a small-scale solar simulator for research and educational purposes. The main goal is to provide a uniform and stable distribution of irradiation from a set of four floodlight halogen lamps, over a targeted area of 40x40 cm2. The floodlights are placed perpendicularly to each other, on the top end of a light tube. Two types of halogen lamps were characterised and the total irradiation of the solar simulator was measured over a 5x5 grid. The results showed that the two arrangements of lamps are able to achieve a level of 1000 W/m2 on the 40x40 cm2 targeted area, but the non-uniformity is unsatisfactory. In order to reach a non-uniformity level of 10% using the proposed lamps arrangements, the targeted area should be reduced to 31x31 cm2.