Academic literature on the topic 'Uv treatment'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Uv treatment.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Uv treatment"

1

Prasetyaningrum, Aji, Widayat Widayat, Bakti Jos, Yudhy Dharmawan, and Ratnawati Ratnawati. "UV Irradiation and Ozone Treatment of κ-Carrageenan: Kinetics and Products Characteristics." Bulletin of Chemical Reaction Engineering & Catalysis 15, no. 2 (March 13, 2020): 319–30. http://dx.doi.org/10.9767/bcrec.15.2.7047.319-330.

Full text
Abstract:
The low molecular weight (LMW) of sulfated polysaccharides including k-carrageenan, is shows a wide spectrum of biological activities. This research investigates the influence of UV irradiation, ozone (O3), and the combination of O3/UV methods on the depolymerization of k-carrageenan. The depolymerization kinetics of k-carrageenan using the Advanced Oxidation Process (UV/O3) was also studied. Furthermore, the intrinsic viscosity method was used to determine the average molecular weight of the research sample, and a mathematical model was developed to predict the kinetic rate constant, as a function of ozone dosage and UV irradiation intensity. Therefore, the physicochemical and morphological properties of the degraded k-carrageenan were analyzed by FT-IR, SEM, and XRD. The intrinsic viscosity k-carrageenan decreases with increasing UV light intensity and ozone concentration. The combination of UV/O3 treatment appeared to be more effective than the individual approaches, as the highest kinetic rate constant for depolymerization was 1.924×10-4 min-1, using 125 mg/L ozone concentration and 40 mW/cm2 of UV lamp intensity. This research also evaluated the relationship between various experimental conditions, including UV lamp power dissipation and ozone concentration on the reaction kinetics model, and the results suggest that lower effect is contributed by UV irradiation intensity. In addition, FT-IR spectra showed the absence of any significant change in the functional properties of k-carrageenan treated with UV and O3 processes, although the morphological properties of the LMW k-carrageenan were rougher and more porous than the native k-carrageenan. Copyright © 2020 BCREC Group. All rights reserved
APA, Harvard, Vancouver, ISO, and other styles
2

KURIHARA, Yuichi, and MASUTAKA Furue. "Carcinogenic Risk of UV Treatment." Nishi Nihon Hifuka 75, no. 3 (2013): 197–99. http://dx.doi.org/10.2336/nishinihonhifu.75.197.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Bozzi, A., A. Lopez, G. Mascolo, and G. Tiravanti. "Pharmaceuticals degradation by UV and UV/H2O2 treatments." Water Supply 2, no. 2 (April 1, 2002): 19–26. http://dx.doi.org/10.2166/ws.2002.0041.

Full text
Abstract:
The degradation by UV and UV/H2O2 treatments of the pharmaceutical intermediate 5-methyl-1,3,4-thiadiazole-2-methylthiol (MMTD-Me) has been investigated and compared to that of its parent compound [5-methyl-1,3,4-thiadiazole-2-thiol (MMTD)] previously studied. The investigation has been carried out with a 17 W low pressure mercury lamp, at room temperature, with an initial MMTD-Me concentration of 1 mg/l and with a molar ratio H2O2/substrate of 100/1. The results show that: (i) the complete MMTD-Me removal is achieved within 60 and 20 minutes by UV and UV/H2O2 treatment respectively; (ii) the UV only irradiation does not cause any MMTD-Me mineralization; (iii) the UV/H2O2 treatment, after 4 hours, leads to a complete mineralization of MMTD-Me organic sulfur and to a partial mineralization of carbon and nitrogen (79 and 16% respectively). Degradation by-products identification, performed by HPLC-UV-MS, revealed that the UV only irradiation gives rise to the sequential transformation of MMTD-Me into two by-products one of which, the last one, accumulates in the solution. Conversely, the UV/H2O2 treatment leads to the formation of two intermediate by-products that undergo further degradation with the breakdown of the thiadiazole ring. These results confirm the effectiveness of UV based processes, alone or in combination with H2O2, in degrading pharmaceutical intermediates.
APA, Harvard, Vancouver, ISO, and other styles
4

Luiz, D. B., A. K. Genena, H. J. José, R. F. P. M. Moreira, and H. Fr Schröder. "Tertiary treatment of slaughterhouse effluent: degradation kinetics applying UV radiation or H2O2/UV." Water Science and Technology 60, no. 7 (October 1, 2009): 1869–74. http://dx.doi.org/10.2166/wst.2009.583.

Full text
Abstract:
In some Brazilian regions, surface water has become scarce, e.g. semi arid climate areas and densely populated and industrial areas, where water over-exploitation and/or fluvial pollution has been more common. Advanced oxidative processes (AOP) provide treated water as a source of reuse water even with the characteristics of drinking water enabling water reuse practices also in food industries. The secondary wastewater of a slaughterhouse was the water source for a tertiary treatment study evaluating the kinetics of the photo-induced degradation of color and UV254 under UV radiation with and without the addition of H2O2. The proximity of the k′ values of color and UV254 degradation by UV indicates that the compounds responsible for color may be the same content measured by UV254. The H2O2/UV treatment was 5.2 times faster than simple UV in removing aromatic compounds. The degradation kinetics of aromatic compounds in both treatments followed a pseudo-first order law. The pseudo-first order constant for H2O2/UV and UV treatments were kUV254′=0.0306 min−1 and kUV254′=0.0056 min−1, respectively.
APA, Harvard, Vancouver, ISO, and other styles
5

Michod, R. E., M. F. Wojciechowski, and M. A. Hoelzer. "DNA repair and the evolution of transformation in the bacterium Bacillus subtilis." Genetics 118, no. 1 (January 1, 1988): 31–39. http://dx.doi.org/10.1093/genetics/118.1.31.

Full text
Abstract:
Abstract The purpose of the work reported here is to test the hypothesis that natural genetic transformation in the bacterium Bacillus subtilis has evolved as a DNA repair system. Specifically, tests were made to determine whether transformation functions to provide DNA template for the bacteria] cell to use in recombinational repair. The survivorship and the homologous transformation rate as a function of dose of ultraviolet irradiation (UV) was studied in two experimental treatments, in which cells were either transformed before (DNA-UV), or after (UV-DNA), treatment with UV. The results show that there is a qualitative difference in the relationship between the survival of transformed cells (sexual cells) and total cells (primarily asexual cells) in the two treatments. As predicted by the repair hypothesis, in the UV-DNA treatment, transformed cells had greater average survivorship than total cells, while in the DNA-UV treatment this relationship was reversed. There was also a consistent and qualitative difference between the UV-DNA and DNA-UV treatments in the relationship between the homologous transformation rate (transformed cells/total cells) and UV dosage. As predicted by the repair hypothesis, the homologous transformation rate increases with UV dose in the UV-DNA experiments but decreases with UV dose in the DNA-UV treatments. However, the transformation rate for plasmid DNA does not increase in a UV-DNA treatment. These results support the DNA repair hypothesis for the evolution of transformation in particular, and sex generally.
APA, Harvard, Vancouver, ISO, and other styles
6

Hann, Seung Kyung, Moo Yon Cho, and Yoon-Kee Park. "UV Treatment of Generalized Prurigo Nodularis." International Journal of Dermatology 29, no. 6 (July 1990): 436–37. http://dx.doi.org/10.1111/j.1365-4362.1990.tb03833.x.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Ruzyllo, J., G. T. Duranko, and A. M. Hoff. "Preoxidation UV Treatment of Silicon Wafers." Journal of The Electrochemical Society 134, no. 8 (August 1, 1987): 2052–55. http://dx.doi.org/10.1149/1.2100818.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

MacLeod, Alex J., Qiangyi Li, Carol Bienek, and Peter R. Foster. "UV-C treatment of protein solutions." Biologicals 35, no. 4 (October 2007): 373. http://dx.doi.org/10.1016/j.biologicals.2006.09.003.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Li, Wei, Liqiang Tan, Yao Zou, Xiaoqin Tan, Jiacheng Huang, Wei Chen, and Qian Tang. "The Effects of Ultraviolet A/B Treatments on Anthocyanin Accumulation and Gene Expression in Dark-Purple Tea Cultivar ‘Ziyan’ (Camellia sinensis)." Molecules 25, no. 2 (January 15, 2020): 354. http://dx.doi.org/10.3390/molecules25020354.

Full text
Abstract:
‘Ziyan’ is a novel anthocyanin-rich tea cultivar with dark purple young shoots. However, how its anthocyanin accumulation is affected by environmental factors, such as ultraviolet (UV), remains unclear. In this study, we observed that UV light treatments stimulated anthocyanin accumulation in ‘Ziyan’ leaves, and we further analyzed the underlying mechanisms at gene expression and enzyme activity levels. In addition, the catechins and chlorophyll contents of young shoots under different light treatments were also changed. The results showed that the contents of total anthocyanins and three major anthocyanin molecules, i.e., delphinidin, cyanidin, and pelargonidin, were significantly higher in leaves under UV-A, UV-B, and UV-AB treatments than those under white light treatment alone. However, the total catechins and chlorophyll contents in these purple tea plant leaves displayed the opposite trends. The anthocyanin content was the highest under UV-A treatment, which was higher by about 66% than control. Compared with the white light treatment alone, the enzyme activities of chalcone synthase (CHS), flavonoid 3′,5′-hydroxylase (F3′5′H), and anthocyanidin synthase (ANS) under UV treatments increased significantly, whereas the leucoanthocyanidin reductase (LAR) and anthocyanidin reductase (ANR) activities reduced. There was no significant difference in dihydroflavonol 4-reductase (DFR) activity under all treatments. Comparative transcriptome analyses unveiled that there were 565 differentially expressed genes (DEGs) of 29,648 genes in three pair-wise comparisons (white light versus UV-A, W vs. UV-A; white light versus UV-B, W vs. UV-A; white light versus UV-AB, W vs. UV-AB). The structural genes in anthocyanin pathway such as flavanone 3-hydroxylase (F3H), F3′5′H, DFR, and ANS, and regulatory gene TT8 were upregulated under UV-A treatment; F3′5′H, DFR, ANS, and UFGT and regulatory genes EGL1 and TT2 were upregulated under UV-AB treatment. However, most structural genes involved in phenylpropanoid and flavonoid pathways were downregulated under UV-B treatment compared with control. The expression of LAR and ANR were repressed in all UV treatments. Our results indicated that UV-A and UV-B radiations can induce anthocyanin accumulation in tea plant ‘Ziyan’ by upregulating the structural and regulatory genes involved in anthocyanin biosynthesis. In addition, UV radiation repressed the expression levels of LAR, ANR, and FLS, resulting in reduced ANR activity and a metabolic flux shift toward anthocyanin biosynthesis.
APA, Harvard, Vancouver, ISO, and other styles
10

Angeles Amaro-Soriano, Fernando Hernández-Aldana, and Antonio Rivera. "Photochemical treatments (UV/H2O2, UV/O3 and UV/H2O2/O3) and inverse osmosis in wastewater: Systematic review." World Journal of Advanced Research and Reviews 10, no. 2 (May 30, 2021): 229–40. http://dx.doi.org/10.30574/wjarr.2021.10.2.0231.

Full text
Abstract:
Every year, the bodies of water receive millions of cubic meters of wastewater from municipal, industrial, agricultural or livestock discharges, treated in an inadequate way or without treatment. The objective of this study was to carry out a systematic review of the frequency of use and effectiveness of the main photochemical processes and the complementation with other treatments such as it is reverse osmosis, used in different types of wastewater effluents. We searched multiple electronic databases (2010-2021), using a stepwise searching approach, supplemented with hand searching. In vitro or in vivo English language publications, original studies, and reviews were included. The database was made up of a total of 100 articles that met the minimum selection criteria, of which 25 articles the maximum scores for analysis. These articles report the improvement in the elimination of pollutants when the treatments are used together and not individually, in relatively short times ranging from 30 minutes of radiation to 8 minutes of exposure to the treatments. Regarding the type of water that was treated, most of the articles report the decontamination of natural wastewater, that is, from the industry without treatment. The percentages calculated to identify research opportunities or gaps in relation to photochemical processes (UV/H2O2/O3). As proposed some authors, if any value of the percentage of pre-selected articles (PAA %) is less than the value of the percentage of failure (MAPAA %), a research opportunity is revealed not addressed by the literature. Based on the percentage results, it is observed that there are no gaps with respect to the photochemical processes or that there are possibly no updates reported in the literature yet.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Uv treatment"

1

Elyasi, Siamak. "Developmemt of UV photoreactor models for water treatment." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/15251.

Full text
Abstract:
Ultraviolet (UV) reactors are promising for the future of drinking water and wastewater treatment technology. Models simulating the performance of UV reactors enhance our understanding of the fundamental principles governing the operation of these units. When modeling the performance of UV reactors, governing equations for all related phenomena are derived and solved. The theoretical models and experimental approaches for evaluating the results of these models are comprehensively reviewed and presented in this research. The thesis presents a step-by-step methodology for solving the governing equations of UV reactors. This research presents a general method that integrates the Fresnell, Snell, and Beer-Lambert laws for modeling the radiant distribution in a medium. The model uses the boundary conditions to realistically simulate the fluence/irradiance rate around the radiant source, in particular, in the zone closest to the radiant source. Different low-pressure UV lamps were tested under different operating conditions using photodiodes and a radiometer. The experimentally measured irradiance rate is in excellent agreement with the results of the simulation. Conventionally, the performance of a UV reactor is evaluated using the concentration of photoreactive chemicals at the outlet vs. the inlet. This research presents a novel method for measuring the concentration distribution of a photoreactive chemical inside a photoreactor using a modified planar laser-induced fluorescence method. The fluence distribution was measured for a pilot scale photoreactor under different operating conditions. The visualized result of the fluence distribution revealed significant information about the local/overall performance of the photoreactor. This method is a powerful diagnostic tool for the determination of the local performance inside a UV reactor, as well as for the evaluation of models simulating UV reactor behavior. A computational fluid dynamic (CFD) model was developed in order to simulate UV photoreactors in the Eulerian framework for microbial disinfection and chemical removal using a UV-based hydroxyl radical initiated oxidation process. The integrated CFD model of UV photoreactor performance was successfully validated by comparisons with experimental results. This verified procedure can be applied to the simulation and optimization of UV photoreactors with different geometries and operating conditions.
APA, Harvard, Vancouver, ISO, and other styles
2

Bridgeforth, Sharonda E. (Sharonda Elaine) 1975. "Groundwater treatment technologies : air stripping vs. UV/oxidation." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/49999.

Full text
Abstract:
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1998.
Includes bibliographical references (leaves 57-58).
by Sharonda E. Bridgeforth.
M.Eng.
APA, Harvard, Vancouver, ISO, and other styles
3

Nguo, Manases Fuh. "TREATMENT OF ODOROUS VOLATILE ORGANIC COMPOUNDS USING UV/H2O2." Thesis, KTH, Energiprocesser, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-90432.

Full text
Abstract:
Odorous volatile organic compounds emissions from fried-food industries posed severed pollution problems both to the workers and the surrounding inhabitants. These industries need to look for cost effective and efficient methods to reduce these emitted gases.  Several solutions such as the use of centrifugation, scrubbers, ion exchangers, biofiltration, condensation, adsorption, absorption, and incineration have been exploited to reduce these smelling gases. Centriair in collaboration with KTH aim at using UV light in combination with ozone and hydrogen peroxide to degrade these odorous VOCs emitted from the frying of meat balls (SCAN) and chips. Several volatile organic compounds which are odorants with low threshold values were identified in the emitted gases from meat frying which includes: aldehydes, sulphur containing compounds, ketones, pyrazines, and alcohols. The type and concentration of these odorants emitted depends among other things primarily on the type of oil used during the frying process.  This work focuses on the use of advanced oxidation processes to abate theses odorous gases. The effect of UV dosage and the use of hydrogen peroxide were tested in a flow reactor. Ozone producing UV lamps were used for the treatment of 2,4-decadienal, Hexanal, furfural, and 2,5-dimethylpyrazine. A simultaneous chemical and odour analysis was done using a GC/MS Olfactometry system. UV/Ozone/H2O2 was effective in reducing the volatile organic compounds tested thus reducing the odor concentration. The percent removal was proportional to the energy dosage.
APA, Harvard, Vancouver, ISO, and other styles
4

Howell, Anne C. "Effects of antioxidant vitamin treatment on UV-irradiated cells." Virtual Press, 1995. http://liblink.bsu.edu/uhtbin/catkey/941360.

Full text
Abstract:
Ultraviolet (UV) radiation damages both eukaryotic and prokaryotic cells by causing the formation of free radicals which damage cell membranes and DNA. Antioxidant vitamins have been shown to protect cells from UV-induced damage by scavenging free radicals. The protection of skin and its normal flora is necessary for the health of individuals in resisting diseases caused by microorganisms and delaying the long-term damage caused by UV radiation.This research investigated the effects of the antioxidants vitamin A and ascorbic acid, as well as UV-irradiation on both prokaryotic (Staphylococcus epidermidis) cells and eukaryotic (human fibroblast skin) cells. This information is important in determining the effects of vitamin treatment on skin and its normal flora.Results indicate that ascorbic acid is rapidly (within six hours) degraded after being dissolved in water or medium. Treatment of cells with ascorbic acid must take into account this rapid degradation. S.epidermidis cells were protected from UV-induced damage by treatment with ascorbic acid but were more sensitive to UV-irradiation when treated with vitamin A. Human fibroblast cells treated with ascorbic acid did not exhibit morphological changes when compared to untreated cells.
Department of Biology
APA, Harvard, Vancouver, ISO, and other styles
5

Chintalapati, Pranav Sankar. "Degradation of cyanobacterial toxin microcystin-LR using UV/vacuum-UV advanced oxidation for drinking water treatment." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/63028.

Full text
Abstract:
Cyanobacterial blooms have been increasing in magnitude and frequency around the world and studies have concluded that climate change, population growth, and industrial development will accelerate this phenomenon. The presence of cyanobacterial blooms in drinking water sources is a concern due to the production of cyanobacterial toxins, which are known to damage internal organs and disrupt nervous system functions. Shallow surface water sources for small water systems are at a greater risk of eutrophication and small, remote communities often lack the resources and infrastructure for adequate treatment. In conventional water systems, instances of cyanobacterial blooms are typically addressed by chemical addition. However, many remote communities are difficult to access and are unable to maintain a consistent supply of chemical oxidants. This study investigated the capability of ultraviolet radiation at 254 nm and 185 nm wavelengths (UV/Vacuum-UV) to degrade microcystin-LR (MC-LR), one of the most commonly occurring and toxic cyanobacterial toxins. Results showed that substantial toxin removal could be achieved solely by direct photolysis with 254 nm. The addition of 185 nm increased MC-LR degradation through advanced oxidation by hydroxyl radicals (•OH). The presence of alkalinity and organic matter (DOC) reduced MC-LR degradation by scavenging •OH. DOC also absorbed 254 nm and 185 nm, requiring additional irradiation time to achieve a target UV dose. Chloride scavenged •OH, but in a reversible reaction, resulting in minimal impact on MC-LR degradation. The order of impact on MC-LR degradation by these common water constituents was DOC>Alkalinity>Chloride. In natural water with a complex matrix, MC-LR could be degraded from a typical concentration (15 µg/L) to below detection (<0.5 µg/L) with a UV254 fluence of 200 mJ/cm2. The presence of cyanobacterial cells impeded MC-LR degradation by adding turbidity to samples, absorbing 254 nm photons and scavenging •OH. However, substantial MC-LR degradation could still be achieved in the presence of cyanobacterial cells. UV/Vacuum-UV appears to be a promising chemical-free technology that is capable of MC-LR degradation in a variety of water conditions, and may be a suitable treatment option for small, remote communities.
Applied Science, Faculty of
Chemical and Biological Engineering, Department of
Graduate
APA, Harvard, Vancouver, ISO, and other styles
6

Van, Huu Tap, Van Tuyen Trinh, and Xuan Hien Dang. "Treatment of leachate by combining PAC and UV/O3 processes." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-99370.

Full text
Abstract:
The landfill leachate is commonly treated for non-biodegradable organic matters, ammonia and colour. Experimental investigations using polyaluminium chlorite (PAC) and UV/O3 have been conducted for the determination of optimal pH value, reaction time and PAC concentration for the removal of chemical oxygen demand (COD) and colour. In pre-treatment coagulation stages, the highest COD and colour removal efficiencies were observed at the concentration of PAC ≥ 3,000 mglG1 and pH values between 7 and 8. However, these experiments also indicated significant removal efficiency for PAC starting with concentrations of 1,500 mglG1. The efficiency of COD and colour removal were approximately 30% and 70%, respectively. Similar efficiencies have been observed also during the second treatment stage where UV/O3 processes were used to treat coagulated leachate. After UV/O3 application, the pH of leachate reached the optimum value of 7.5 whereas the highest COD and colour removal efficiency was 55% and 72%, respectively, and the optimal reaction time was achieved after 80 min
Nước rỉ rác sinh ra từ bãi chôn lấp chất thải rắn cần được xử lý các thành phần chất hữu cơ khó phân hủy sinh học, xử lí amoni và độ màu. Một số kết quả thử nghiệm về xử lý COD và màu của nước rỉ rác bằng việc sử dụng phương pháp keo tụ với PAC và quá trình UV/O3 đã được thực hiện cùng với việc xác định các giá trị pH tối ưu, thời gian phản ứng và nồng độ PAC tối ưu. Hiệu suất xử lý cao nhất đạt được khi nồng độ của PAC ≥ 3.000 mg/l, pH trong khoảng từ 7 đển 8 trong giai đoạn tiền xử lý. Tuy nhiên, hiệu quả loại bỏ COD và màu bắt đầu tăng rõ khi nồng độ PAC từ 1.500 mg/l trở lên. Hiệu quả loại bỏ COD và màu tương ứng là khoảng 30% và 70%. Các giá trị pH này phù hợp cho quá trình phản ứng UV/O3 được sử dụng sau giai đoạn keo tụ. Sau quá trình xử lý bằng hệ UV/O3, pH của nước rỉ rác tối ưu được xác định là 7,5 (hiệu suất xử lý COD và màu cao nhất tương ứng là 55% và 72%), thời gian phản ứng tối ưu là 80 phút
APA, Harvard, Vancouver, ISO, and other styles
7

Gao, Jiong. "UV/Sodium Percarbonate for Treatment of Bisphenol A in Water." University of Cincinnati / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin161710940946631.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Obande, Matthew A. "Effect of preharvest UV-treatment on shelf life of fruits and vegetables." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/7768.

Full text
Abstract:
The benefits of low UV dose treatment of horticultural produce – also known as hormetic treatment - have been attested to in numerous studies conducted over the last 15 years. However, commercial growers have not adopted the concept of hormesis. With increasingly stringent controls on the use of fungicides and other chemical agents the time has come to examine how hormetic treatment might be applied in the horticulture sector. The objectives of this work were firstly, to confirm UV-induced hormetic effects applied postharvest for a number of different types of produce, namely, tomatoes, broccoli, strawberries and mangoes. Secondly, to evaluate the use of rollers to ensure full surface treatment of produce, and thirdly to evaluate the possibility of treating produce preharvest. In order to investigate surface UV dose distributions, a polystyrene sphere (Diameter 70 mm) was used to simulate fruits such as tomatoes, apples, peaches etc., that have an approximately spherical form. Biodosimetry based on spores of Bacillus subtilis was employed to experimentally determine UV doses and to compare the results obtained with theoretical predictions. Good agreement was obtained and the modelling approach was extended to other types of produce. This showed the amenability of mechanical rollers to ensure full surface treatment of produce. Postharvest treatment of produce was carried using conventional low intensity UV sources principally emitting at 254 nm and also a commercially available high energy pulsed UV source. Treatment using the conventional UV source was carried out on mechanical rollers within a UV cabinet designed for this work at a fixed distance from the source and at an intensity of 1000 μW/cm2. A 5 minute conventional UV treatment of tomatoes was approximately comparable to fruit given a 3-pulsed treatment using the pulsed source (507 J/pulse of polychromatic light). The colour and texture of both groups of fruit were significantly maintained as compared with controls. The treated tomatoes also showed a significant increase in the ascorbic acid levels during storage. Similarly, a 15 minute conventional UV treatment of broccoli heads was comparable to heads given a 10-pulsed treatment using the pulsed source. Where both treatments gave rise to a statistically significant retention of green colour of treated broccoli. In addition, mangoes given a 10 minute conventional UV treatment were comparable to fruit given a 20-pulsed treatment using the pulsed source with both treatments leading to maintenance of texture as compared to control fruit. This confirmed the UV-hormetic effects. The effects of conventional and pulsed treatments are compared and discussed. Preharvest treatment of tomatoes and strawberries was carried out in commercial glasshouses. Doses of either 3 or 8 kJ/m2 were delivered to the fruits using a treatment device designed for the work, which delivered a combined intensity of 2000 μW/cm2 from two low pressure UV sources. The treated tomatoes showed a delay in development of colour as measured on the vine and after picking. Picked tomatoes were inoculated with P. digitatum and C. gloeosporioides and the results obtained showed a significant inhibition of the development of the fungi in the treated fruit during the storage period. These results suggest that the beneficial response shown by the preharvest treatment is not a localised one but a systematically induced resistance observable throughout the treated plant. This was shown by monitoring tomato fruits on treated plants which themselves where not directly exposed to the UV light. The two doses elicited different responses in the treated strawberries, with the 8 kJ/m2 dose causing the fruit to redden significantly faster than the 3 kJ/m2 treated fruits and controls. This could have significant nutritional benefit as the red colour of strawberries has been correlated with anthocyanin levels. On the other hand, treatment at the lower UV dose led to a lag in colour development. The amenability of the equipment utilised for commercial application is discussed.
APA, Harvard, Vancouver, ISO, and other styles
9

Huang, Ying. "Applications of UV/H2O2, UV/NO3–, and UV-vis/ferrite/sulfite Advanced Oxidation Processes to Remove Contaminants of Emerging Concern for Wastewater Treatment." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1535703890003601.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

GONCALVES, ADRIANA CINOPOLI. "TREATMENT OF EFFLUENTS CONTAINING FREE CYANIDE THROUGH THE SYSTEM H2O2/UV." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2004. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=6043@1.

Full text
Abstract:
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
O presente trabalho teve como objetivo estudar o tratamento de efluentes contendo cianeto livre através do sistema H2O2/UV e selecionar as condições operacionais mais adequadas para uma maior eficiência do processo. Para isso, foram empregadas soluções sintéticas de KCN com características de pH e concentração similares às condições de um efluente industrial real. O fotorreator utilizado nos testes de oxidação foi um reator cilíndrico de seção anular, equipado com uma lâmpada de baixa pressão de 28 W concêntrica com emissão em 254 nm, onde a solução ficava diretamente em contato com a mesma. Este fotorreator foi acoplado a um sistema de refrigeração que mantinha a temperatura de operação em 25oC.As variáveis avaliadas foram concentração inicial de cianeto em solução, pH inicial da solução, potência de UV irradiada e razão molar [H2O2]/[CN-]. Para soluções contendo uma concentração inicial de cianeto igual a 100 ppm, foi possível atingir uma eficiência remoção de 99,9 por cento em 25 minutos, em pH igual a 9,5, com uma razão molar [H2O2]:[CN-] igual a 3. Para efluentes contendo uma concentração inicial de cianeto igual a 300 ppm, nas mesmas condições operacionais, alcançou-se a mesma eficiência em 30 minutos.
The present work had the objective of studying the treatment of effluents containing free cyanide through the system H2O2/UV, and of selecting the best operational conditions for best efficiency of the process. For that, it was employed synthetic solutions of KCN with characteristics of pH and concentration similar to those of a real effluent. The photoreactor employed in the oxidation tests was a cylindrical reactor of annular section, equipped with a concentrical low pressure lamp of 28 W with emission in 254 nm, where the solution was in direct contact with the lamp. This photoreactor was coupled with a cooling system which kept the operation temperature at 25oC. The evaluated variables were initial cyanide concentration in solution, initial pH of the solution, power of radiated UV and molar ratio [H2O2]/[CN-]. For solutions containing an initial concentration of cyanide equal to 100 ppm, it was possible to reach a removal efficiency of 99.9 per cent in 25 minutes, in pH equal to 9.5, with a molar ratio of [H2O2]:[CN-] equal to 3. For effluents containing an initial concentration of cyanide equal to 300 ppm, at the same operational conditions, it was possible to achieve the same removal efficiency in 30 minutes.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Books on the topic "Uv treatment"

1

David, Gaithuma, Heath Mark, Schulz Chris, Bogan Travis, and Water Research Foundation, eds. UV disinfection knowledge base. Denver, CO: Water Research Foundation, 2012.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

S, Cushing Robert, Crozes Gil F, and AWWA Research Foundation, eds. Practical aspects of UV disinfection. Denver, CO: AWWA Research Foundation and American Water Works Association, 2001.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Wright, Harold. Design and performance guidelines for UV sensor systems. Denver, Colorado]: Water Research Foundation, 2009.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Gagnon, Graham A. Impact of UV disinfection on biological stability. Denver, CO: Awwa Research Foundation, 2004.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

Linden, Karl G. Disinfection efficiency and dose measurement of polychromatic UV light. Denver, CO: Awwa Research Foundation, 2003.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

Linden, Karl G. Impact of UV and UV/H₂O₂ AOP on EDC activity in water. Denver, Colo: Awwa Research Foundation, 2007.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

Linden, Karl G. Impact of UV and UV/H₂O₂ AOP on EDC activity in water. Denver, Colo: Awwa Research Foundation, 2007.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

Linden, Karl G. Impact of UV location and sequence on by-product formation. Denver, Colo: Water Research Foundation, 2012.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

Wobma, Paul C. UV disinfection and disinfection by-product characteristics of unfiltered water. Denver, CO: Awwa Research Foundation, 2004.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

New York State Energy Research and Development Authority. Evaluation of ultraviolet (UV) radiation disinfection technologies for wastewater treatment plant effluent: Final report. Albany, N.Y: NYSERDA, 2004.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Book chapters on the topic "Uv treatment"

1

von Sonntag, Clemens. "Disinfection with UV-Radiation." In Process Technologies for Water Treatment, 159–77. Boston, MA: Springer US, 1988. http://dx.doi.org/10.1007/978-1-4684-8556-1_15.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Petres, J., B. Fietze-Fischer, and R. Rompel. "Surgical Treatment of Non-Melanoma Skin Cancer." In Skin Cancer and UV Radiation, 1174–82. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/978-3-642-60771-4_135.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Bachter, D., B. R. Balda, H. Vogt, and H. Büchels. "The Sentinel Lymphonodectomy in the Treatment of Malignant Melanomas." In Skin Cancer and UV Radiation, 1189–97. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/978-3-642-60771-4_137.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

von Laue, H. B. "Mistletoe Treatment for Melanoma Brain Metastases: A Single Case." In Skin Cancer and UV Radiation, 1315–22. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/978-3-642-60771-4_154.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Konstantinow, A., and B. R. Balda. "Extracorporeal Photochemotherapy in the Treatment of Cutaneous T Cell Lymphoma." In Skin Cancer and UV Radiation, 484–91. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/978-3-642-60771-4_58.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Dirschka, Th, G. von Kobyletzki, M. Freitag, T. Reuther, P. Altmeyer, and M. Kerscher. "A New Treatment Modality of Localized Scleroderma: Low-Dose UVA1 Phototherapy." In Skin Cancer and UV Radiation, 455–61. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/978-3-642-60771-4_54.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Larkö, Olle. "Home Uv Treatment of Psoriasis - An Update." In Light in Biology and Medicine, 181–82. Boston, MA: Springer US, 1988. http://dx.doi.org/10.1007/978-1-4613-0709-9_23.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Sharmazan, S., L. Kalyuzhnaya, and V. Sakalo. "The Application of Nd-Yag Laser in the Surgical Treatment of Skin Cancer." In Skin Cancer and UV Radiation, 1296–98. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/978-3-642-60771-4_150.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Koch, U., J. Schaller, and D. Metze. "Telecommunication of Digitized Dermatoscopic Images Improves Histopathological Examination and Surgical Treatment of Skin Lesions." In Skin Cancer and UV Radiation, 1162–64. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/978-3-642-60771-4_133.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Ernst, T. M., and T. Höppner. "Improvement of the Therapy of Actinic Keratoses with 5-Fluorouracil: Clinical Results of a Treatment with a Low Dose Patch." In Skin Cancer and UV Radiation, 1284–87. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/978-3-642-60771-4_148.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Uv treatment"

1

Castillo, Fabian. "Use of EM Technology (EM) in water treatment: Urban sewage water treatment plan, a city slaughter house, and a natural estuary in Guayaquil, Ecuador." In 2018 4th International Conference on Universal Village (UV). IEEE, 2018. http://dx.doi.org/10.1109/uv.2018.8642155.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Sanchez, Lily, Victor Tarashenko, Steve Oster, Francis Wang, and Gary Johnson. "Innovative UV Technology for Water Treatment Systems." In World Water and Environmental Resources Congress 2005. Reston, VA: American Society of Civil Engineers, 2005. http://dx.doi.org/10.1061/40792(173)131.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Kathiravan Krishnamurthy, Ali Demirci, and Joseph M Irudayaraj. "Milk Pasteurization by Pulsed UV-light Treatment." In 2004, Ottawa, Canada August 1 - 4, 2004. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2004. http://dx.doi.org/10.13031/2013.16935.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Chen, Shu-Fang, Ching-Yu Chang, and Yao-Ching Ku. "Resist residue removal using UV ozone treatment." In SPIE Advanced Lithography, edited by Robert D. Allen. SPIE, 2010. http://dx.doi.org/10.1117/12.849449.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Fernandes, Fabiano Andre Narciso, Thayane Rabelo Braga, Ebenezer Oliveira Silva, and Sueli Rodrigues. "Drying of mangoes applying pulsed UV light as pre-treatment." In 21st International Drying Symposium. Valencia: Universitat Politècnica València, 2018. http://dx.doi.org/10.4995/ids2018.2018.7303.

Full text
Abstract:
High intensity pulsed UV Light is a non-thermal treatment used in sanitization of fruits and vegetables. In this work, we have applied high intensity pulsed UV light as a pretreatment for convective air-drying evaluating the benefits of the pretreatment to the drying process and to the nutritional quality of the dried product. Mangoes were subjected to pulses of UV light. The pretreated samples were further dried in a convective oven-drier until 90% of the initial water content has been removed. Drying kinetics, water apparent diffusivity, vitamin B, vitamin C content and total carotenoids content were analyzed. Pulsed UV light showed to be an interesting pretreatment for mangoes given the higher nutritional content of the dried product. Keywords: mango; drying; ultraviolet; vitamins; kinetics
APA, Harvard, Vancouver, ISO, and other styles
6

Dobre, Robert A., and Norocel D. Codreanu. "UV laboratory platform for treatment of photosensitive materials." In 2013 36th International Spring Seminar on Electronics Technology (ISSE). IEEE, 2013. http://dx.doi.org/10.1109/isse.2013.6648288.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Lincoln, Victor A. C., Marcio M. Mello, and Liliane Ventura. "UV transmittance during the crosslinking procedure: tunable treatment." In SPIE BiOS, edited by Fabrice Manns, Per G. Söderberg, and Arthur Ho. SPIE, 2014. http://dx.doi.org/10.1117/12.2036641.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Gao, Munan, Winston Schoenfeld, and Ngwe Zin. "UV-Ozone Oxide Treatment for Improved Surface Passivation." In Optical Devices and Materials for Solar Energy and Solid-state Lighting. Washington, D.C.: OSA, 2020. http://dx.doi.org/10.1364/pvled.2020.pvtu2g.5.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Thompson, Theresa, and Jay Pasquantonio. "High-intensity UV LED inactivation of Clostridium difficile spores." In Photonic Diagnosis, Monitoring, Prevention, and Treatment of Infections and Inflammatory Diseases 2019, edited by Tianhong Dai, Mei X. Wu, and Jürgen Popp. SPIE, 2019. http://dx.doi.org/10.1117/12.2507993.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Bischoff, Martin, Tobias Nowitzki, Oliver Voß, Steffen Wilbrandt, and Olaf Stenzel. "Post-deposition treatment of IBS coatings for UV applications." In Optical Interference Coatings. Washington, D.C.: OSA, 2013. http://dx.doi.org/10.1364/oic.2013.pmb.10.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Uv treatment"

1

Koziel, Jacek, Yael Laor, Jeffrey Zimmerman, Robert Armon, Steven Hoff, and Uzi Ravid. Simultaneous Treatment of Odorants and Pathogens Emitted from Confined Animal Feeding Operations (CAFOs) by Advanced Oxidation Technologies. United States Department of Agriculture, January 2009. http://dx.doi.org/10.32747/2009.7592646.bard.

Full text
Abstract:
A feasibility study was conducted, aiming to explore the potential effectiveness of UV/TiO2/O3 photooxidation technologies for simultaneous treatment of odorant and pathogen emissions from livestock and poultry operations. Several key parameters were tested in laboratory (US) and semi-pilot (Israel) scale conditions including: the effects of light energy dose (treatment time and light intensity), relative humidity and air temperature, UV wavelength, presence of photocatalyst (TiO2) and the presence of ozone. Removal and conversion of odor, target gases (sulfur-containing volatile organic compounds S-VOCs, volatile fatty acids (VFAs), phenolics, and ammonia), and airborne pathogens was tested. Up to 100% removal (below method detection level) of S-VOCs, VFAs, and phenolics, the overall odor, and up to 64.5% of ammonia was achieved with optimized treatment. Treatments involving deep UV band (185 nm) and photocatalyst (TiO2) were more efficient in removal/conversion of odorous gases and odor. The estimate of the operational cost of treatment was based on measured emissions of several odorous VOCs from full scale, commercial swine farm ranges from $0.15 to $0.59 per finisher pig. This figure represents significantly lower cost compared with the cost of biofiltration or air scrubbing.
APA, Harvard, Vancouver, ISO, and other styles
2

Cline, J. E., P. F. Sullivan, M. A. Lovejoy, J. Collier, and C. D. Adams. Ozone/UV treatment to enhance biodegradation of surfactants in industrial wastewater. CRADA final report. Office of Scientific and Technical Information (OSTI), October 1996. http://dx.doi.org/10.2172/666205.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Chalutz, Edo, Charles Wilson, Samir Droby, Victor Gaba, Clauzell Stevens, Robert Fluhr, and Y. Lu. Induction of Resistance to Postharvest Diseases and Extension of Shelf-Life of Fruits and Vegetables by Ultra-Violet Light. United States Department of Agriculture, February 1994. http://dx.doi.org/10.32747/1994.7568093.bard.

Full text
Abstract:
Following preliminary observations by one of the collaborating scientists on this project and the completion of a 1-year, BARD-supported feasibility study (IS-1908-90F), this 3-year BARD project has been executed. The main objectives of the research were to elucidate biochemical and pathological aspects of UV-induced resistance in fruits and vegetables, to characterize physical and biological variables of induced resistance and delay of ripening, and to explore the application of the treatment as a control practice of postharvest diseases and shelf-life extension of fruits and vegetables. Our findings, which are detailed in numerous joint publications, have shown that the effect of UV-C light on induction of resistance and delay of ripening is a general one and of wide oddurrence. Apart from surface sterilization of the commodity, the reduction of decay of different fungi has been associated with and induced resistance phenomenon which gradually builds up within 24 to 48 hours after the UV treatment and can be reversed by visible light. In citrus, induced resistance has been associated with increased activity of the enzymes phenylalanine ammonia-lyase and peroxidase, and with the levels of endglucanase and chitinase. In tomato, resistance was correlated with the production of high levels of tomatine. Our study of some molecular aspects of the induced resistance in grapefruit has revealed the induction of a cDNA which represents a gene encoding for an isoflavone reductase-like protein that, in legumes, has been associated with phytoalexin biosynthesis. This gene was cloned and sequenced. Delay of ripening was associated in tomato with inhibition of ethylene production, carotenoid synthesis, and chlorophyll degradation and with the presence of high levels of polyamines. In peach fruit epiphytic populations of a yeast increased following the UV treatment. Pilot-size treatment and packing lines were constructed in the US and Israel to test the application of the UV treatment on a semi-commercial scale. Although effective in reduction of decay and delay of ripening, a number of problems will have to be addressed before practical application of this methodology can be realized. The main issues are associated with the temporal and variable response to the treatment, and its relationship to the maturity and date of harvest of the commodity.
APA, Harvard, Vancouver, ISO, and other styles
4

MacDonald, James D., Aharon Abeliovich, Manuel C. Lagunas-Solar, David Faiman, and John Kabshima. Treatment of Irrigation Effluent Water to Reduce Nitrogenous Contaminants and Plant Pathogens. United States Department of Agriculture, July 1993. http://dx.doi.org/10.32747/1993.7568092.bard.

Full text
Abstract:
The contamination of surface and subterranean drinking water supplies with nitrogen-laden agricultural wastewater is a problem of increasing concern in the U.S. and Israel. Through this research, we found that bacteria could utilize common organic wastes (e.g. paper, straw, cotton) as carbon sources under anaerobic conditions, and reduce nitrate concentrations in wastewater to safe levels. Two species of bacteria, Cellulomonas uda and a Comamonas sp., were required for dentitrification. Celulomonas uda degraded cellulose and reduced nitrate to nitrite. In addition, it excreted soluble organic carbon needed as a food source by the Comamonas sp. for completion of denitrification. We also found that recirculated irrigation water contains substantial amounts of fungal inoculum, and that irrigating healthy plants with such water leads to significant levels of root infection. Water can be disinfected with UV, but our experiments showed that Hg-vapor lamps do not possess sufficient energy to kill spores in wastewater containing dissolved organics. Excimer lasers and Xenon flashlamps do possess the needed power levels, but only the laser had a high enough repetition rate to reliably treat large volumes of water. Ozone was highly efficacious, but it's use as a water treatment is probably best suited to moderate or low volume irrigation systems. This research provides critical data needed for the design of effective water denitrification and/or pathogen disinfection systems for different growing operations.
APA, Harvard, Vancouver, ISO, and other styles
5

Ovalle, Samuel, E. Viamontes, and Tony Thomas. Optimization of DLP 3D Printed Ceramic Parts. Florida International University, October 2021. http://dx.doi.org/10.25148/mmeurs.009776.

Full text
Abstract:
Digital Light Processing (DLP) 3D printing allows for the creation of parts with advanced engineering materials and geometries difficult to produce through conventional manufacturing techniques. Photosensitive resin monomers are activated with a UV-producing LCD screen to polymerize, layer by layer, forming the desired part. With the right mixture of photosensitive resin and advanced engineering powder material, useful engineering-grade parts can be produced. The Bison 1000 is a research-grade DLP printer that permits the user to change many parameters, in order to discover an optimal method for producing 3D parts of any material of interest. In this presentation, the process parameter optimization and their influence on the 3D printed parts through DLP technique will be discussed. The presentation is focused on developing 3D printable slurry, printing of complex ceramic lattice structures, as well as post heat treatment of these DLP-produced parts.
APA, Harvard, Vancouver, ISO, and other styles
6

Kennedy, Alan, Andrew McQueen, Mark Ballentine, Brianna Fernando, Lauren May, Jonna Boyda, Christopher Williams, and Michael Bortner. Sustainable harmful algal bloom mitigation by 3D printed photocatalytic oxidation devices (3D-PODs). Engineer Research and Development Center (U.S.), April 2022. http://dx.doi.org/10.21079/11681/43980.

Full text
Abstract:
The impacts of Harmful Algal Blooms (HAB), often caused by cyanobacteria (Figure 1), on water resources are increasing. Innovative solutions for treatment of HABs and their associated toxins are needed to mitigate these impacts and decrease risks without introducing persistent legacy contaminants that cause collateral ecosystem impacts. This technical note (TN) identifies novel opportunities enabled by Additive Manufacturing (AM), or 3D printing, to produce high surface area advanced material composites to rapidly prototype sustainable environmental solutions for aquatic nuisance species control. This innovative research explores deployment of 3D-printable polymer composite structures containing nano-scale photocatalysts for targeted open water treatment of HABs that are customizable to the site-of-concern and also retrievable, reusable, and sustainable. The approach developed to control cyanobacteria HAB events has the potential to augment or replace broadcast, non-specific chemical controls that otherwise put non-target species and ecological resources at long-term risk. It can also augment existing UV-treatment HAB treatment control measures. The expected research outcome is a novel, effective, and sustainable HAB management tool for the US Army Corps of Engineers (USACE) and resource managers to deploy in their HAB rapid response programs. The research will provide a framework for scale-up into other manufacturing methods (e.g., injection molding) to produce the devices in bulk (quickly and efficiently). Research for this project title “Mitigation of Harmful Algal Bloom Toxins using 3D Printed Photocatalytic Materials (FY21-23)” was sponsored by the US Army Engineer Research Development Center’s (ERDC) Aquatic Nuisance Species Research Program (ANSRP).
APA, Harvard, Vancouver, ISO, and other styles
7

Crouch, Rebecca, Jared Smith, Bobbi Stromer, Christian Hubley, Samuel Beal, Guilherme Lotufo, Afrachanna Butler, et al. Preparative, extraction, and analytical methods for simultaneous determination of legacy and insensitive munition (IM) constituents in aqueous, soil or sediment, and tissue matrices. Engineer Research and Development Center (U.S.), August 2021. http://dx.doi.org/10.21079/11681/41480.

Full text
Abstract:
No standard method exists for determining levels of insensitive munition (IM) compounds in environmental matrices. This project resulted in new methods of extraction, analytical separation and quantitation of 17 legacy and 7 IM compounds, daughter products of IM, and other munition compounds absent from USEPA Method 8330B. Extraction methods were developed for aqueous (direct-injection and solid-phase extraction [SPE]), soil, sediment, and tissue samples using laboratory-spiked samples. Aqueous methods were tested on 5 water sources, with 23 of 24 compounds recovered within DoD QSM Ver5.2 limits. New solvent extraction (SE) methods enabled recovery of all 24 compounds from 6 soils within QSM limits, and a majority of the 24 compounds were recovered at acceptable levels from 4 tissues types. A modified chromatographic treatment method removed analytical interferences from tissue extracts. Two orthogonal high-performance liquid chromatography-ultraviolet (HPLC-UV) separation methods, along with an HPLC–mass spectrometric (HPLC-MS) method, were developed. Implementing these new methods should reduce labor and supply costs by approximately 50%, requiring a single extraction and sample preparation, and 2 analyses rather than 4. These new methods will support environmental monitoring of IM and facilitate execution of risk-related studies to determine long-term effects of IM compounds.
APA, Harvard, Vancouver, ISO, and other styles
8

Borch, Thomas, Yitzhak Hadar, and Tamara Polubesova. Environmental fate of antiepileptic drugs and their metabolites: Biodegradation, complexation, and photodegradation. United States Department of Agriculture, January 2012. http://dx.doi.org/10.32747/2012.7597927.bard.

Full text
Abstract:
Many pharmaceutical compounds are active at very low doses, and a portion of them regularly enters municipal sewage systems and wastewater-treatment plants following use, where they often do not fully degrade. Two such compounds, CBZ and LTG, have been detected in wastewater effluents, surface waters, drinking water, and irrigation water, where they pose a risk to the environment and the food supply. These compounds are expected to interact with organic matter in the environment, but little is known about the effect of such interactions on their environmental fate and transport. The original objectives of our research, as defined in the approved proposal, were to: Determine the rates, mechanisms and products of photodegradation of LTG, CBZ and selected metabolites in waters exposed to near UV light, and the influence of DOM type and binding processes on photodegradation. Determine the potential and pathways for biodegradation of LTG, CBZ and selected metabolites using a white rot fungus (Pleurotusostreatus) and ADP, and reveal the effect of DOM complexation on these processes. Reveal the major mechanisms of binding of LTG, CBZ and selected metabolites to DOM and soil in the presence of DOM, and evaluate the effect of this binding on their photodegradation and/or biodegradation. We determined that LTG undergoes relatively slow photodegradation when exposed to UV light, and that pH affects each of LTG’s ability to absorb UV light, the efficiency of the resulting reaction, and the identities of LTG’sphotoproducts (t½ = 230 to 500 h during summer at latitude 40 °N). We observed that LTG’sphotodegradation is enhanced in the presence of DOM, and hypothesized that LTG undergoes direct reactions with DOM components through nucleophilic substitution reactions. In combination, these data suggest that LTG’s fate and transport in surface waters are controlled by environmental conditions that vary with time and location, potentially affecting the environment and irrigation waters. We determined that P. ostreatusgrows faster in a rich liquid medium (glucose peptone) than on a natural lignocellulosic substrate (cotton stalks) under SSF conditions, but that the overall CBZ removal rate was similar in both media. Different and more varied transformation products formed in the solid state culture, and we hypothesized that CBZ degradation would proceed further when P. ostreatusand the ᵉⁿᶻʸᵐᵃᵗⁱᶜ ᵖʳᵒᶠⁱˡᵉ ʷᵉʳᵉ ᵗᵘⁿᵉᵈ ᵗᵒ ˡⁱᵍⁿⁱⁿ ᵈᵉᵍʳᵃᵈᵃᵗⁱᵒⁿ. ᵂᵉ ᵒᵇˢᵉʳᵛᵉᵈ ¹⁴C⁻Cᴼ2 ʳᵉˡᵉᵃˢᵉ ʷʰᵉⁿ ¹⁴C⁻ᶜᵃʳᵇᵒⁿʸˡ⁻ labeled CBZ was used as the substrate in the solid state culture (17.4% of the initial radioactivity after 63 days of incubation), but could not conclude that mineralization had occurred. In comparison, we determined that LTG does not degrade in agricultural soils irrigated with treated wastewater, but that P. ostreatusremoves up to 70% of LTG in a glucose peptone medium. We detected various metabolites, including N-oxides and glycosides, but are still working to determine the degradation pathway. In combination, these data suggest that P. ostreatuscould be an innovative and effective tool for CBZ and LTG remediation in the environment and in wastewater used for irrigation. In batch experiments, we determined that the sorption of LTG, CBZ and selected metabolites to agricultural soils was governed mainly by SOM levels. In lysimeter experiments, we also observed LTG and CBZ accumulation in top soil layers enriched with organic matter. However, we detected CBZ and one of its metabolites in rain-fed wheat previously irrigated with treated wastewater, suggesting that their sorption was reversible, and indicating the potential for plant uptake and leaching. Finally, we used macroscale analyses (including adsorption/desorption trials and resin-based separations) with molecular- level characterization by FT-ICR MS to demonstrate the adsorptive fractionation of DOM from composted biosolids by mineral soil. This suggests that changes in soil and organic matter types will influence the extent of LTG and CBZ sorption to agricultural soils, as well as the potential for plant uptake and leaching.
APA, Harvard, Vancouver, ISO, and other styles
9

Rahimipour, Shai, and David Donovan. Renewable, long-term, antimicrobial surface treatments through dopamine-mediated binding of peptidoglycan hydrolases. United States Department of Agriculture, January 2012. http://dx.doi.org/10.32747/2012.7597930.bard.

Full text
Abstract:
There is a need for renewable antimicrobial surface treatments that are semi- permanent, can eradicate both biofilms and planktonic pathogens over long periods of time and that do not select for resistant strains. This proposal describes a dopamine binding technology that is inexpensive, bio-friendly, non-toxic, and uses straight-forward commercially available products. The antimicrobial agents are peptidoglycanhydrolase enzymes that are non-toxic and highly refractory to resistance development. The goal of this project is to create a treatment that will be applicable to a wide variety of surfaces and will convey long-lasting antimicrobial activity. Although the immediate goal is to create staphylolytic surfaces, the technology should be applicable to any pathogen and will thus contribute to no less than 3 BARD priorities: 1) increased animal production by protecting animals from invasive and emerging diseases, 2) Antimicrobial food packaging will improve food safety and security and 3) sustainable bio- energy systems will be supported by coating fermentation vats with antimicrobials that could protect ethanolic fermentations from Lactobacillus contamination that reduces ethanol yields. The dopamine-based modification of surfaces is inspired by the strong adhesion of mussel adhesion proteins to virtually all types of surfaces, including metals, polymers, and inorganic materials. Peptidoglycanhydrolases (PGHs) meet the criteria of a surface bound antimicrobial with their site of action being extracellular peptidoglycan (the structural basis of the bacterial cell wall) that when breached causes osmotic lysis. As a proof of principle, we will develop technology using peptidoglycanhydrolase enzymes that target Staphylococcus aureus, a notoriously contagious and antimicrobial-resistant pathogen. We will test for susceptibility of the coating to a variety of environmental stresses including UV light, abrasive cleaning and dessication. In order to avoid resistance development, we intend to use three unique, synergistic, simultaneous staphylococcal enzyme activities. The hydrolases are modular such that we have created fusion proteins with three lytic activities that are highly refractory to resistance development. It is essential to use multiple simultaneous activities to avoid selecting for antimicrobial resistant strains. This strategy is applicable to both Gram positive and negative pathogens. We anticipate that upon completion of this award the technology will be available for commercialization within the time required to achieve a suitable high volume production scheme for the required enzymes (~1-2 years). We expect the modified surface will remain antimicrobial for several days, and when necessary, the protocol for renewal of the surface will be easily applied in a diverse array of environments, from food processing plants to barnyards.
APA, Harvard, Vancouver, ISO, and other styles
10

Poverenov, Elena, Tara McHugh, and Victor Rodov. Waste to Worth: Active antimicrobial and health-beneficial food coating from byproducts of mushroom industry. United States Department of Agriculture, January 2014. http://dx.doi.org/10.32747/2014.7600015.bard.

Full text
Abstract:
Background. In this proposal we suggest developing a common solution for three seemingly unrelated acute problems: (1) improving sustainability of fast-growing mushroom industry producing worldwide millions of tons of underutilized leftovers; (2) alleviating the epidemic of vitamin D deficiency adversely affecting the public health in both countries and in other regions; (3) reducing spoilage of perishable fruit and vegetable products leading to food wastage. Based on our previous experience we propose utilizing appropriately processed mushroom byproducts as a source of two valuable bioactive materials: antimicrobial and wholesome polysaccharide chitosan and health-strengthening nutrient ergocalciferol⁽ᵛⁱᵗᵃᵐⁱⁿ ᴰ2⁾. ᴬᵈᵈⁱᵗⁱᵒⁿᵃˡ ᵇᵉⁿᵉᶠⁱᵗ ᵒᶠ ᵗʰᵉˢᵉ ᵐᵃᵗᵉʳⁱᵃˡˢ ⁱˢ ᵗʰᵉⁱʳ ᵒʳⁱᵍⁱⁿ ᶠʳᵒᵐ ⁿᵒⁿ⁻ᵃⁿⁱᵐᵃˡ ᶠᵒᵒᵈ⁻ᵍʳᵃᵈᵉ source. We proposed using chitosan and vitamin D as ingredients in active edible coatings on two model foods: highly perishable fresh-cut melon and less perishable health bars. Objectives and work program. The general aim of the project is improving storability, safety and health value of foods by developing and applying a novel active edible coating based on utilization of mushroom industry leftovers. The work plan includes the following tasks: (a) optimizing the UV-B treatment of mushroom leftover stalks to enrich them with vitamin D without compromising chitosan quality - Done; (b) developing effective extraction procedures to yield chitosan and vitamin D from the stalks - Done; (c) utilizing LbL approach to prepare fungal chitosan-based edible coatings with optimal properties - Done; (d) enrichment of the coating matrix with fungal vitamin D utilizing molecular encapsulation and nano-encapsulation approaches - Done, it was found that no encapsulation methods are needed to enrich chitosan matrix with vitamin D; (e) testing the performance of the coating for controlling spoilage of fresh cut melons - Done; (f) testing the performance of the coating for nutritional enhancement and quality preservation of heath bars - Done. Achievements. In this study numerous results were achieved. Mushroom waste, leftover stalks, was treated ʷⁱᵗʰ ᵁⱽ⁻ᴮ ˡⁱᵍʰᵗ ᵃⁿᵈ ᵗʳᵉᵃᵗᵐᵉⁿᵗ ⁱⁿᵈᵘᶜᵉˢ ᵃ ᵛᵉʳʸ ʰⁱᵍʰ ᵃᶜᶜᵘᵐᵘˡᵃᵗⁱᵒⁿ ᵒᶠ ᵛⁱᵗᵃᵐⁱⁿ ᴰ2, ᶠᵃʳ ᵉˣᶜᵉᵉᵈⁱⁿᵍ any other dietary vitamin D source. The straightforward vitamin D extraction procedure and ᵃ ˢⁱᵐᵖˡⁱᶠⁱᵉᵈ ᵃⁿᵃˡʸᵗⁱᶜᵃˡ ᵖʳᵒᵗᵒᶜᵒˡ ᶠᵒʳ ᵗⁱᵐᵉ⁻ᵉᶠᶠⁱᶜⁱᵉⁿᵗ ᵈᵉᵗᵉʳᵐⁱⁿᵃᵗⁱᵒⁿ ᵒᶠ ᵗʰᵉ ᵛⁱᵗᵃᵐⁱⁿ ᴰ2 ᶜᵒⁿᵗᵉⁿᵗ suitable for routine product quality control were developed. Concerning the fungal chitosan extraction, new freeze-thawing protocol was developed, tested on three different mushroom sources and compared to the classic protocol. The new protocol resulted in up to 2-fold increase in the obtained chitosan yield, up to 3-fold increase in its deacetylation degree, high whitening index and good antimicrobial activity. The fungal chitosan films enriched with Vitamin D were prepared and compared to the films based on animal origin chitosan demonstrating similar density, porosity and water vapor permeability. Layer-by-layer chitosan-alginate electrostatic deposition was used to coat fruit bars. The coatings helped to preserve the quality and increase the shelf-life of fruit bars, delaying degradation of ascorbic acid and antioxidant capacity loss as well as reducing bar softening. Microbiological analyses also showed a delay in yeast and fungal growth when compared with single layer coatings of fungal or animal chitosan or alginate. Edible coatings were also applied on fresh-cut melons and provided significant improvement of physiological quality (firmness, weight ˡᵒˢˢ⁾, ᵐⁱᶜʳᵒᵇⁱᵃˡ ˢᵃᶠᵉᵗʸ ⁽ᵇᵃᶜᵗᵉʳⁱᵃ, ᵐᵒˡᵈ, ʸᵉᵃˢᵗ⁾, ⁿᵒʳᵐᵃˡ ʳᵉˢᵖⁱʳᵃᵗⁱᵒⁿ ᵖʳᵒᶜᵉˢˢ ⁽Cᴼ2, ᴼ²⁾ ᵃⁿᵈ ᵈⁱᵈ not cause off-flavor (EtOH). It was also found that the performance of edible coating from fungal stalk leftovers does not concede to the chitosan coatings sourced from animal or good quality mushrooms. Implications. The proposal helped attaining triple benefit: valorization of mushroom industry byproducts; improving public health by fortification of food products with vitamin D from natural non-animal source; and reducing food wastage by using shelf- life-extending antimicrobial edible coatings. New observations with scientific impact were found. The program resulted in 5 research papers. Several effective and straightforward procedures that can be adopted by mushroom growers and food industries were developed. BARD Report - Project 4784
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography