sunlight radiation
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2021 ◽  
Vol 17 (1) ◽  
pp. 45-57
Author(s):  
Linus N. Okoro ◽  
Immaculata O. Onuigbo ◽  
Bolade O. Agboola

The present study examined how sunlight radiation, temperature and time in Yola climate can affect the physicochemical properties of drinking water in polyethylene terephthalate (PET) bottle in Yola Metropolis Nigeria. Conductivity, total dissolved solids (TDS), chemical oxygen demand (COD), pH, Cl-, and NO3 - were analyzed using standard methods for 42 days. Solvent extraction and GC-MS analysis were conducted periodically to monitor the appearance and identity of any migrant organic compounds. Sunlight exposure had the highest impact wherein conductivity, TDS, and COD trended upwards while pH decreased over time. However, Cl- and NO3- stayed constant. The GC-MS results showed the highest concentration of organic compounds in the sunlight exposed samples showing the molecular ion peak of benzene. Conversely, the negative control samples, stored in a cool dry place, showed no signs of leachates.



Photochem ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 287-301
Author(s):  
Javier Segarra-Martí ◽  
Sara M. Nouri ◽  
Michael J. Bearpark

The study of radiation effects in DNA is a multidisciplinary endeavour, connecting the physical, chemical and biological sciences. Despite being mostly filtered by the ozone layer, sunlight radiation is still expected to (photo)ionise DNA in sizeable yields, triggering an electron removal process and the formation of potentially reactive cationic species. In this manuscript, photoionisation decay channels of important DNA tautomeric derivatives, 7H-adenine and 7H-guanine, are characterised with accurate CASSCF/XMS-CASPT2 theoretical methods. These simulation techniques place the onset of ionisation for 7H-adenine and 7H-guanine on average at 8.98 and 8.43 eV, in line with recorded experimental evidence when available. Cationic excited state decays are analysed next, uncovering effective barrierless deactivation routes for both species that are expected to decay to their (cationic) ground state on ultrafast timescales. Conical intersection topographies reveal that these photoionisation processes are facilitated by sloped single-path crossings, known to foster photostability, and which are predicted to enable the (VUV) photo-protection mechanisms present in these DNA tautomeric species.



2021 ◽  
Author(s):  
Jaafar Hasan ◽  
Jing Wang ◽  
Zhentao Wang ◽  
Muhammad Idrees ◽  
Saima Batool ◽  
...  

Abstract The reduced graphene oxide dopped equaixial geometry TiO2 (rGO/egTiO2) composite as photocatalyst was synthesized hydrothermally with various mass ratios of tetrabutyl titanate. The photocatalyst is considered to be rGO/equaixial geometry TiO2 in terms of modifying the combined reduced graphene Oxide and TiO2. The rGO plays a vital role in rGO/egTiO2 composite as photocatalysts were analyzed in methylene blue (MB) and rhodamine B (RhB) photocatalytic degradation under UV and simulated solar light irradiation. This synthesized catalyst was characterized by various analytical techniques such as XPS, XRD, SEM, BET and TEM. The rGO/egTiO2 composite exhibits enhanced photo-catalytic performance with degradation rate of 97.5 and 97% on RhB and MB for 60 min under UV radiation respectively, while the degradation rate of 94 and 92 % was observed on the same dyes for 6 h under the simulated sunlight radiation. The enhanced photocatalytic performance of the rGO/egTiO2 composite under ultraviolet irradiation source was owing to a high separation efficiency of the photo-induced electron-hole pairs, while the photocatalytic performance under simulated sunlight radiation was due to the photosensitive and charge separator behavior of rGO. This offers us an excellent potential of significant photo catalytic activity for the removal of organic contaminants from wastewater.



Diagnostics ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1104
Author(s):  
Siti Raihanah Abdani ◽  
Mohd Asyraf Zulkifley ◽  
Nuraisyah Hani Zulkifley

Pterygium is an eye condition that is prevalent among workers that are frequently exposed to sunlight radiation. However, most of them are not aware of this condition, which motivates many volunteers to set up health awareness booths to give them free health screening. As a result, a screening tool that can be operated on various platforms is needed to support the automated pterygium assessment. One of the crucial functions of this assessment is to extract the infected regions, which directly correlates with the severity levels. Hence, Group-PPM-Net is proposed by integrating a spatial pyramid pooling module (PPM) and group convolution to the deep learning segmentation network. The system uses a standard mobile phone camera input, which is then fed to a modified encoder-decoder convolutional neural network, inspired by a Fully Convolutional Dense Network that consists of a total of 11 dense blocks. A PPM is integrated into the network because of its multi-scale capability, which is useful for multi-scale tissue extraction. The shape of the tissues remains relatively constant, but the size will differ according to the severity levels. Moreover, group and shuffle convolution modules are also integrated at the decoder side of Group-PPM-Net by placing them at the starting layer of each dense block. The addition of these modules allows better correlation among the filters in each group, while the shuffle process increases channel variation that the filters can learn from. The results show that the proposed method obtains mean accuracy, mean intersection over union, Hausdorff distance, and Jaccard index performances of 0.9330, 0.8640, 11.5474, and 0.7966, respectively.



Author(s):  
Allan T Showler ◽  
Jessica L Harlien

Abstract The house fly, Musca domestica L. (Diptera: Muscidae), is a nuisance pest often associated with livestock production, and it can also mechanically transmit the causal agents of human and veterinary diseases. We found that a 0.5% concentration of p-anisaldehyde, produced by many plants consumed by humans, repelled adult M. domestica in static air olfactometer tubes under laboratory conditions for ≥24 h, but by 48 h the repellent activity had worn off. Repellency, however, was not observed in response to 0.5% p-anisaldehyde that had been exposed to sunlight radiation lamps for 2 h. When p-anisaldehyde was aged in darkness for 48 h, it showed strong initial repellency for <1 h. The repellent action of 0.5% p-anisaldehyde was sufficient to keep adult M. domestica from landing on three different food sources when the botanical substance was misted onto the food sources, and when it was placed in proximity to, but not in contact with, the food sources. Extension of p-anisaldehyde’s repellent action using solvents other than acetone is discussed.



Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3080
Author(s):  
Lucía Rodríguez-López ◽  
Raquel Cela-Dablanca ◽  
Avelino Núñez-Delgado ◽  
Esperanza Álvarez-Rodríguez ◽  
David Fernández-Calviño ◽  
...  

In view of the rising relevance of emerging pollutants in the environment, this work studies the photodegradation of three antibiotics, evaluating the effects of the pH of the medium and the concentration of dissolved organic matter. Simulated light (with a spectrum similar to that of natural sunlight) was applied to the antibiotics Ciprofloxacin (Cip), Clarithromycin (Cla) and Trimethoprim (Tri), at three different pH, and in the presence of different concentrations of humic acids. The sensitivity to light followed the sequence: Cip > Cla > Tri, which was inverse for the half-life (Tri > Cla > Cip). As the pH increased, the half-life generally decreased, except for Cla. Regarding the kinetic constant k, in the case of Cip and Tri it increased with the rise of pH, while decreased for Cla. The results corresponding to total organic carbon (TOC) indicate that the complete mineralization of the antibiotics was not achieved. The effect of humic acids was not marked, slightly increasing the degradation of Cip, and slightly decreasing it for Tri, while no effect was detected for Cla. These results may be relevant in terms of understanding the evolution of these antibiotics, especially when they reach different environmental compartments and receive sunlight radiation.



2021 ◽  
Vol 141 (5) ◽  
pp. S89
Author(s):  
D. Bacqueville ◽  
C. Jacques-Jamin ◽  
H. Dromigny ◽  
F. Boyer ◽  
D. Redoulès ◽  
...  


2021 ◽  
Vol 12 ◽  
Author(s):  
Pianpian Fan ◽  
Qin Wang ◽  
Jing Li ◽  
Chunyan Lu ◽  
Yong Xu ◽  
...  

ObjectiveVitamin D plays an important role in bone and mineral metabolism. Ultraviolet B (UVB) is the primary determinant for vitamin D synthesis. However, population-based data of vitamin D status was sparse in areas with sunlight deprivation in China. This study aimed to assess serum 25-hydroxyvitamin D [25(OH)D] levels among adult women in Sichuan basin with the lowest sunlight radiation in China, and the associations with sunlight exposure and age.MethodsIn the context of the same ethnicity, similar latitude and lifestyle in sunlight-limited basin and sunlight-abundant plateau, 1,057 women in basin and 337 in plateau aged 29–95 years were included in this study, from November 2012 to February 2013. Daily sunlight exposure duration of previous month was obtained using questionnaires. Serum 25(OH)D was measured by enzyme-linked immunosorbent assay.ResultsThe prevalence of vitamin D severe deficiency [25(OH)D <30 nmol/L] and deficiency [30 ≤ 25(OH)D <50 nmol/L] was significantly higher in basin than plateau (21.85% vs. 10.09%, and 59.32% vs. 40.36%; P<0.0001). Women from basin exhibited lower serum 25(OH)D levels than those from plateau (40.66 ± 15.62 vs. 52.54 ± 19.94 nmol/L, P<0.0001). In basin, women more than 50 years old had higher 25(OH)D than younger counterparts, and 25(OH)D level of these groups was not associated with sunlight exposure duration. While in plateau, women younger than 60 years old had higher 25(OH)D than the older women. Furthermore, for those younger groups, women with long sunlight exposure (≥3 h daily) had higher 25(OH)D concentration than those with short sunlight exposure (<3 h daily). Serum PTH was negatively associated with 25(OH)D in basin, but not in plateau.ConclusionsAlarmingly high prevalence of vitamin D deficiency was observed in women in sunlight-deprived basin in Sichuan. Only the vitamin D status of younger women from plateau with adequate solar radiation could benefit from sunlight exposure. Vitamin D supplementation and vitamin D-fortified food should be encouraged to improve vitamin D status for women living in sunlight-limited areas, or with old age.



2021 ◽  
Vol 83 (4) ◽  
pp. 863-876
Author(s):  
Maressa Maria de Melo Santos Moura ◽  
Victor Estolano Lima ◽  
Antônio Acacio de Melo Neto ◽  
Alex Leandro Andrade de Lucena ◽  
Daniella Carla Napoleão ◽  
...  

Abstract The solution mixture of the non-steroidal anti-inflammatory drugs ketoprofen, meloxicam and tenoxicam was degraded through systems, composed of different photocatalysts based on TiO2 (Fe and Cu) and the hydrogen peroxide oxidant. The monitoring was performed by UV-Vis spectroscopy. Under sunlight radiation, a reduction in peaks was observed with the use of impregnated photocatalysts. After 60 min, the sun/H2O2/Fe-TiO2 system reached degradations of 46.5% and 93.2% at 260 and 367 nm, respectively, and was selected for further studies. The degradation kinetic reached 92 and 96% of degradation after 180 min, for the λ of 260 and 367 nm, respectively. The kinetic curve could be represented by the empirical model proposed by Nichela and co-authors, indicating that besides the heterogeneous photocatalysis that occurs at the surface of the TiO2 there is also the joint effect of the photo-Fenton process. After the treatment, there was no toxicity to cress and lettuce seeds. However, a sensitivity of the thyme seeds to the compounds formed during the treatment was verified. After the fifth treatment cycle, the supported photocatalyst showed degradation higher than 82%. These results indicate that this system is suitable for the treatment of effluents containing pharmaceutical compounds.



2020 ◽  
Vol 17 (11) ◽  
pp. 5020-5024
Author(s):  
Ciro Rodriguez ◽  
Doris Esenarro ◽  
Jorge Jave ◽  
Fabiola Martínez ◽  
Juan Puma ◽  
...  

The proposal of a renewable energy theme park aims to sensitize the use of clean energy, the integration of ecotourism as an economic activity and environmental sustainability of the population of Tomas in Peru, to turn it into an identity reference point regional and local. For this, the green axis is composed of a series of elements such as thematic squares, vegetation segments, recreation, and incorporation of renewable energies. The bioclimatic architectural design of the theme park is related to the balance of nature’s surroundings, so a series of renewable energy prototypes is proposed in a theme park that takes advantage the use of natural resources from sunlight, radiation, winds, organic waste, among others, which are the components of the proposal. Likewise, interactive education is considered among the resident population of Tomas, and with their renewable resources are the pillars, to sensitize visitors, in caring for the environment.



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