scholarly journals Pengaruh Jumlah Sinar Ultra Violet Terhadap Penurunan Kandungan Bahan Organik di Dalam Pengolahan Air Gambut yang Dilanjutkan dengan Saringan Pasir Lambat

2019 ◽  
Vol 1 (2) ◽  
pp. 21-24
Author(s):  
M Ma’arij Harfadli
Keyword(s):  
Uv Irradiation ◽  
Uv Light ◽  
Peat Soil ◽  
Ultra Violet ◽  
Water Source ◽  
Raw Water ◽  
Optimum Time ◽  
Organic Matters ◽  
Uv Reactor ◽  
Uv Lamps

One of the areas with a complicated drinking are the areas with peat soil. This area has a lot water source, one of treatments for peat water is variation in using the UV light for peat water processing.There is reactors in this research: the UV reactor is made of glass with a 6 liters of reactor volume. The reactor contains 15 watts of 3 ultra violet UV lamps. Processing raw water is done in batch and reactor continuously. The wavelength is 370 nm which initial absorbance value of 2.045. The optimum time occurs 30 minutes in 3 lamp of UV irradiation with the elimination of organic matters of 36 mg / l.73%.

Observations of TiO2 Surfaces Using Totally Reflected X-ray In-plane Diffraction Under UV Irradiation

2002 ◽  
Vol 751 ◽  
Author(s):  
T. Horiuchi ◽  
H. Ochi ◽  
K. Kaisei ◽  
K. Ishida ◽  
K. Matsushige
Keyword(s):  
Uv Irradiation ◽  
Uv Light ◽  
Plane Surface ◽  
Signal To Noise Ratio ◽  
High Surface ◽  
Ultra Violet ◽  
High Signal ◽  
X Ray ◽  
Force Microscopy ◽  
Catalytic Activities

ABSTRACTSurface lattice displacements of titanium dioxide (TiO2: rutile) during ultra-violet (UV) light irradiation have been investigated using a total reflection x-ray diffraction, which provides a high signal to noise ratio (S/N) and superior in-plane surface diffraction. Under the environments in vapors of H2O, CH3OH, C2H5OH and C3H6OH, the photo-catalytic activities of TiO2 (110), (100) and (001) surfaces subject to UV irradiation have been measured. It is found that the diffraction peaks and their full width half maxima (FWHMs) show some peculiarities with respect to the photo-catalytic activities in both surface lattices and adsorbed molecules in vapors. Furthermore, Kelvin force microscopy (KFM) has showed that there exists a very high surface potential, probably due to surface atom displacements induced by UV irradiation. With regard to the origin of the photo-catalytic activities, the induced surface potentials are discussed.

scholarly journals Demonstration and evaluation of germicidal UV-LEDs for point-of-use water disinfection

2010 ◽  
Vol 8 (3) ◽  
pp. 479-486 ◽  
Author(s):  
Christie Chatterley ◽  
Karl Linden
Keyword(s):  
Uv Irradiation ◽  
Uv Light ◽  
Low Pressure ◽  
Water Disinfection ◽  
Light Emitting ◽  
E Coli ◽  
Point Of Use ◽  
One Year ◽  
Uv Lamps ◽  
Uv Leds

Ultraviolet (UV) irradiation is a common disinfection option for water treatment in the developed world. There are a few systems installed in developing countries for point-of-use treatment, but the low-pressure mercury lamps currently used as the UV irradiation source have a number of sustainability issues including a fragile envelope, a lifetime of approximately one year, and they contain mercury. UV light emitting diodes (LEDs) may offer solutions to many of the sustainability issues presented by current UV systems. LEDs are small, efficient, have long lifetimes, and do not contain mercury. Germicidal UV LEDs emitting at 265 nm were evaluated for inactivation of E. coli in water and compared to conventional low-pressure UV lamps. Both systems provided an equivalent level of treatment. A UV-LED prototype was developed and evaluated as a proof-of-concept of this technology for a point-of-use disinfection option, and the economics of UV-LEDs were evaluated.

Pursuing the effect of aeration, pH increment, and H2O2 coupled with UV irradiation on the removal efficiency of manganese by microfilter membrane

2000 ◽  
Vol 41 (10-11) ◽  
pp. 25-31 ◽  
Author(s):  
Md. Abdur Rahman ◽  
J.Y. Huang ◽  
Y. Iwakami ◽  
K. Fujita
Keyword(s):  
Removal Efficiency ◽  
Uv Irradiation ◽  
Oxidation Process ◽  
Uv Light ◽  
Raw Water ◽  
Manganese Removal ◽  
Turbidity Level ◽  
Filter Water ◽  
Ph Level ◽  
Very High

Aeration, a very common method used in conventional water treatment industries for oxidation and mixing purposes, was used along with pH increment for removal of manganese by microfilter membrane. However, experiments showed that aeration instead of accelerating the manganese oxidation process as normally expected rather declined the manganese removal percentage by a noticeable difference from that obtained by pH increment alone. As high as 97% manganese removal could be attained by microfilter membrane with an increased pH level of 9.7 of the raw water, whereas the removal percentage was reduced to 60% when the mechanical aeration was incorporated. H2O2, being activated by UV light decomposes into very reactive OH-radical which is of very high oxidizing potential and can break down or change the physical properties of even very strongly-bonded compounds which then can be removed by any suitable physical means. From this principle, H2O2 coupled with UV irradiation was also included in the experiment of manganese removal by microfilter membrane to pursue it's manganese removal efficiency. However, experiments showed that a negative manganese removal occurred with amount of manganese in the filter water surpassing the amount of manganese in the raw water. Also a very high trend in the manganese and turbidity level was found in the membrane washed drain water, which helped conclude that H2O2 coupled with UV irradiation should not be used as a process for manganese removal by microfilter membrane, rather it can be used as a process for washing of the membrane module.

Case Study of Particle-Related UV Shielding of Microorganisms When Disinfecting Unfiltered Surface Water

2010 ◽  
Vol 45 (3) ◽  
pp. 343-351 ◽  
Author(s):  
Raymond E. Cantwell ◽  
Ron Hofmann ◽  
Jennie L. Rand ◽  
Patrick M. Devine ◽  
Monique VanderMarck
Keyword(s):  
Surface Water ◽  
Uv Light ◽  
Pilot Scale ◽  
Uv Disinfection ◽  
Particle Count ◽  
Uv Reactor ◽  
Before And After ◽  
Log Linear ◽  
Uv Lamps

Abstract The goal of this case study was to provide pilot-scale information about the ability of ultraviolet (UV) light to disinfect unfiltered surface water. A pilot-scale (0.25 L/s) UV reactor with low-pressure UV lamps was installed on raw water entering an aqueduct from the Pardee Reservoir at the East Bay Municipal District, California. A pilot monitoring system also collected hourly particle count (2 to 100 m), turbidity, and ultraviolet transmittance (UVT) measurements for 14 months. Grab microbial samples were collected and analyzed for indigenous total coliforms and total aerobic spores (TAS) both before and after UV disinfection, to correlate survival of the organisms across the UV reactor to water quality characteristics. Concentrations of indigenous coliforms and TAS ranged up to 163 and 1,383 per 100 mL respectively, before UV exposure. The data showed that the ability of UV to disinfect coliforms was essentially unaffected by the presence of particles (up to 703>10 m per mL and 1.3 nephelometric turbidity unit [NTU]) in the unfiltered surface water. In 13 of 14 samples, no coliforms were detected in the UV treated water. Log-linear inactivation of TAS up to 2.5-log suggests that at least 99.6% of the TAS were not protected from UV disinfection by particles.

Aplikasi metode tahanan jenis dalam studi geologi karst Gua Seropan di Gunung Kidul, Yogyakarta

2017 ◽  
Vol 12 (2) ◽  
pp. 105-116
Author(s):  
Pulung A. Pranantya ◽  
Nurlia Sadikin
Keyword(s):  
Fresh Water ◽  
Ground Surface ◽  
Water Source ◽  
Raw Water ◽  
Limited Information ◽  
Resistivity Method ◽  
Central Java ◽  
Underground River ◽  
Initial Exploration

In terms of geology, most areas in south of the Gunungkidul District in Central Java consist of the Wonosari formation limestone. The land is generally very dry and source of raw water is also difficult to reach. Findings on the existence of underground river in caves, however, indicate the potential amount of water within the area, especially in the eastern part of the Gunungkidul District. Although limited information available, some fishermen have discovered that Seropan cave contains fresh water source. This cave is situated at 65 m below the cliff. Initial exploration, which done using a multichannel resistivity method, confirmed the availability of freshwater in the cave and underground river. The isopach of cave depth is found in ranges of 80 200 m below the ground surface. The water of Seropan cave can be utilized by implementing pipeline or by drilling at the suggested point based on the interpretation results, i.e. 110o2223.6388 EL 8o42.874 SL. [DY1][PP2][DY1]Perbaiki grammarIn terms of geology, most areas in south of Gunungkidul District in Central Java consist of the Wonosari formation limestone. The land is generally very dry and source of raw water is also difficult to reach. Findings on the exixtence of underground river in caves, however, indicate potential amount of water within the area especially in eastern part of Gunungkidul District. Although limited information available, some fishermans has discovered that Seropan cave contain fresh water source. This cave is situated at 65 m below the cliff. Initial exploration, which done using multichannel resistivity method, confirmed the availability of freshwater in the cave and underground river. The iso pach of cave depth is found in ranges of 80 200 m below the ground surface. The water of Seropan cave can be utilized by implementing pipeline or by drilling at the suggested point based on the interpretation results i.e. 110o2223.6388 EL 8o42.874 SL.[PP2]Sudah diperbaiki

scholarly journals Effect of Water Leaching on Photodegraded Scots Pine and Spruce Timbers Monitored by FTIR Spectroscopy

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 833
Author(s):  
Edina Preklet ◽  
László Tolvaj ◽  
Eszter Visi-Rajczi ◽  
Tamás Hofmann
Keyword(s):  
Ftir Spectroscopy ◽  
Scots Pine ◽  
Uv Irradiation ◽  
Chemical Elements ◽  
Uv Light ◽  
Carbonyl Groups ◽  
Water Leaching ◽  
Absorption Bands ◽  
Chemical Changes ◽  
Absorption Increase

The goal of this research was the systematic study and comparison of the divided individual effects of UV light irradiation and water leaching during artificial weathering. Spruce (Picea abies Karst.) and Scots pine (Pinus sylvestris L.) samples were irradiated by ultraviolet (UV) light. Another sequence of samples was treated with the combination of UV irradiation and water leaching. The total extent of UV treatment was 20 days for both series of samples. Time relation of UV irradiation and water leaching was 2:1. The chemical changes were observed by FTIR spectroscopy. The difference spectrum was used for determination of the chemical changes. Degradation of lignin was greater for the leached samples than for the pure UV treated samples. Scots pine suffered greater lignin degradation than spruce, and produced higher absorption increase on the absorption region of unconjugated carbonyls. The unconjugated carbonyl groups were the most responsive chemical elements to leaching. Spruce was more susceptible to leaching of unconjugated carbonyl groups than Scots pine. Two absorption bands of unconjugated carbonyl groups at 1706 and 1764 cm−1 wavenumbers were produced by photodegradation. The absorption band at 1764 cm−1 was more sensitive to water leaching than the band at 1706 cm−1.

scholarly journals Effect of Pre-Harvest Supplemental UV-A/Blue and Red/Blue LED Lighting on Lettuce Growth and Nutritional Quality

Horticulturae ◽  
2021 ◽  
Vol 7 (4) ◽  
pp. 80
Author(s):  
Triston Hooks ◽  
Joseph Masabni ◽  
Ling Sun ◽  
Genhua Niu
Keyword(s):  
Blue Light ◽  
Nutritional Quality ◽  
Uv Light ◽  
Ultra Violet ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Daily Light Integral ◽  
Lettuce Growth ◽  
Supplemental Lighting

Blue light and ultra-violet (UV) light have been shown to influence plant growth, morphology, and quality. In this study, we investigated the effects of pre-harvest supplemental lighting using UV-A and blue (UV-A/Blue) light and red and blue (RB) light on growth and nutritional quality of lettuce grown hydroponically in two greenhouse experiments. The RB spectrum was applied pre-harvest for two days or nights, while the UV-A/Blue spectrum was applied pre-harvest for two or four days or nights. All pre-harvest supplemental lighting treatments had a same duration of 12 h with a photon flux density (PFD) of 171 μmol m−2 s−1. Results of both experiments showed that pre-harvest supplemental lighting using UV A/Blue or RB light can increase the growth and nutritional quality of lettuce grown hydroponically. The enhancement of lettuce growth and nutritional quality by the pre-harvest supplemental lighting was more effective under low daily light integral (DLI) compared to a high DLI and tended to be more effective when applied during the night, regardless of spectrum.

scholarly journals UV-induced neuronal degeneration in the rat cerebral cortex

2021 ◽  
Author(s):  
Mariko Nakata ◽  
Masayuki Shimoda ◽  
Shinya Yamamoto
Keyword(s):  
Uv Irradiation ◽  
Neuronal Degeneration ◽  
Uv Light ◽  
Brain Lesion ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Heme Oxygenase 1 ◽  
Dependent Manner ◽  
Focal Brain Injury ◽  
The Brain ◽  
And Oxidative Stress

Abstract Irradiation with ultraviolet (UV) light on the cortical surface can induce a focal brain lesion (UV lesion) in rodents. In the present study, we investigated the process of establishing a UV lesion. Rats underwent UV irradiation (365 nm wavelength, 2.0 mWh) over the dura, and time-dependent changes in the cortical tissue were analyzed histologically. We found that the majority of neurons in the lesion started to degenerate within 24 hours and the rest disappeared within 5 days after irradiation. UV-induced neuronal degeneration progressed in a layer-dependent manner. Moreover, UV-induced terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) positivity and heme oxygenase-1 (HO-1) immunoreactivity were also detected. These findings suggest that UV irradiation in the brain can induce gradual neural degeneration and oxidative stress. Importantly, UV vulnerability may vary among cortical layers. UV-induced cell death may be due to apoptosis; however, there remains a possibility that UV-irradiated cells were degenerated via processes other than apoptosis. The UV lesion technique will not only assist in investigating brain function at a targeted site but may also serve as a pathophysiological model of focal brain injury and/or neurodegenerative disorders.

Optimization of ultraviolet irradiation of Clarias gariepinus (Burchell, 1822) eggs for androgen production

Zygote ◽  
2021 ◽  
pp. 1-6
Author(s):  
Victor Tosin Okomoda ◽  
Haziqah Jumahat Nursyaza ◽  
Ijabo Oga Samuel ◽  
Anuar Hassan ◽  
Abraham Sunday Oladimeji ◽  
...  
Keyword(s):  
Survival Rate ◽  
Uv Irradiation ◽  
Uv Light ◽  
Clarias Gariepinus ◽  
African Catfish ◽  
Chromosome Counting ◽  
Complete Inactivation ◽  
Cell Cleavage ◽  
Optimal Protocol ◽  
Prolonged Duration

Summary The optimum distance and duration of ultraviolet (UV) irradiation for the complete inactivation of African catfish Clarias gariepinus egg nucleus was investigated in this study. The UV light was suspended above the unfertilized eggs at four distances (5, 10, 20 and 30 cm) and for five durations (1, 2, 3, 4 and 5 min). Then, the irradiated eggs were activated with sperm from diploid C. gariepinus and cold shocked at 5°C for 5 min just moments before cell cleavage. Ploidy analysis was performed using karyotype chromosome counting. The results obtained suggested that the further the distance, the better the hatchability rate, however prolonged duration seemed to significantly reduced hatchability. All treatments with surviving progenies at the end of the study showed evidence of successfully diploid gynogen (2n = 56) induction at different percentages. However, the optimal protocol that gave a moderately high hatchability/survival rate and completely induced gynogens was exposure of the eggs to UV irradiation at 20 cm for 1 min. It was concluded that the distance and duration of UV irradiation affects gynogenetic induction in African catfish C. gariepinus.

scholarly journals Ultramicro Analysis of Odorous Materials by Massfragmentography in Raw Water Source of Water Supply

1978 ◽  
Vol 98 (1) ◽  
pp. 124-128
Author(s):  
YOSHITERU TSUCHIYA ◽  
TOSHIHIKO OKAMOTO
Keyword(s):  
Water Supply ◽  
Water Source ◽  
Raw Water
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