MODIFICATION OF NANO HYBRID PES-ZNO MEMBRANE USING UV IRRADIATION FOR BIODIESEL PURIFICATION

2020 ◽  
Vol 82 (5) ◽  
Author(s):  
Tutuk Djoko Kusworo ◽  
Andri Cahyo Kumoro ◽  
Muhammad Ainul Yaqin ◽  
Nurul Fatiyah ◽  
Dani Puji Utomo
Keyword(s):  
Uv Irradiation ◽  
Uv Light ◽  
Biodiesel Production ◽  
Polymer Composition ◽  
Nano Zno ◽  
Membrane Performance ◽  
Flux Profile ◽  
Biodiesel Purification

The purification of biodiesel is one of the crucial processes involved in biodiesel production. This study aims to examine the effect of the polymer composition, nano-ZnO loading, and UV irradiation on the performance of membranes for biodiesel purification. The membranes were fabricated with the polyethersulfone composition of 17, 18, and 20 wt%. The compositions of nano ZnO were varied at 1.5, 2, and 2.5 wt%, while the duration of UV irradiation was varied for 0.5, 1, and 1.5 minutes. The results indicate that the compositions of PES, nano ZnO, and UV irradiation affected the performance of the membrane. The best membrane performance was achieved when the membrane was produced using PES 17 wt%, nano ZnO 1.5 wt% involving irradiation UV light for 1 minute. The fabricated membrane exhibits 3 hours flux profile stability and 61.5% glycerol rejection.

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 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.

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 Enhanced Humidity Sensing Response of SnO2/Silicon Nanopillar Array by UV Irradiation

Sensors ◽  
2019 ◽  
Vol 19 (9) ◽  
pp. 2141 ◽  
Author(s):  
Wei Li ◽  
Linlin Wang ◽  
Yun Cai ◽  
Peifeng Pan ◽  
Jinze Li ◽  
...  
Keyword(s):  
Magnetron Sputtering ◽  
Response Time ◽  
Specific Surface ◽  
Uv Irradiation ◽  
Recovery Time ◽  
Room Temperature ◽  
Uv Light ◽  
Humidity Sensing ◽  
Potential Applications ◽  
Humidity Sensitivity

In this work, a silicon nanopillar array was created with nanosphere lithography. SnO2 film was deposited on this nanostructure by magnetron sputtering to form an SnO2/silicon nanopillar array sensor. The humidity sensitivity, response time, and recovery time were all measured at room temperature (25 °C) with UV or without UV irradiation. As a result, the humidity sensitivity properties were improved by enlarging the specific surface area with ordered nanopillars and irradiating with UV light. These results indicate that nanostructure sensors have potential applications in the field of sensors.

Covalent linkage of [Phe2,Phe(p-N3)3]AVP to vasopressin receptors

1984 ◽  
Vol 246 (5) ◽  
pp. C486-C493 ◽  
Author(s):  
P. Eggena ◽  
F. Fahrenholz ◽  
I. L. Schwartz
Keyword(s):  
Uv Irradiation ◽  
Uv Light ◽  
Covalent Binding ◽  
Receptor Interaction ◽  
Receptor System ◽  
Covalent Linkage ◽  
Osmotic Water ◽  
Vasopressin Receptors ◽  
History Of ◽  
Osmotic Water Flow

We have shown previously ( Eggena et al., Endocrinology 113: 1413-1421, 1983) that [Phe2,Phe(p-N3)3]-AVP induces a prolonged hydrosmotic response in the toad bladder when activated by ultraviolet (UV) light. To determine whether this response is due to covalent binding of the ligand with 8-arginine vasopressin (AVP) receptors, bladders were challenged with the ligand in the presence of AVP or the AVP antagonist, [Phe(p-N3)2]AVP, during photolysis. The permeability of bladders to water was tested subsequently in the absence of hormone or analogue. Bladders with a history of exposure to AVP (or to [Phe-(p-N3)2]AVP) during UV irradiation were considerably less permeable to water than controls, suggesting that [Phe2,Phe(p-N3)3]AVP, AVP, and [Phe(p-N3)2]AVP compete for the same receptor system during photolysis. Other experiments were directed at defining optimal conditions for covalent linkage of [Phe2,Phe(p-N3)3]AVP to receptors. These studies have indicated that two 10-min cycles of UV irradiation are more effective than one and that osmotic water flow at a rate of 1 mg X min-1 X cm-2 during irradiation does not interfere with the ligand-receptor interaction. Acidification of the serosal bath solution to pH 6.5 did not inhibit covalent binding of the ligand to receptors during photolysis. However, the capacity of the ligand-receptor complex to increase bladder permeability to water was markedly inhibited by serosal fluid acidification. These experiments have suggested that [Phe2 ,Phe(p-N3)3]AVP binds covalently to AVP receptors during photolysis and generates a signal that gradually decays as a function of time.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of 172-nm UV irradiation on polyimide and its application in surface modification by grafting

2020 ◽  
Vol 32 (7) ◽  
pp. 761-774
Author(s):  
Lopamudra Das ◽  
John C Poutsma ◽  
Michael J Kelley
Keyword(s):  
Uv Irradiation ◽  
Photoelectron Spectroscopy ◽  
Secondary Ion Mass Spectrometry ◽  
Mechanical Stability ◽  
Uv Light ◽  
Force Microscopy ◽  
Angle Measurements ◽  
Wide Range ◽  
Grafting Reactions ◽  
Sample Position

Polyimides (PIs) have a wide range of industrial and scientific applications due to their excellent thermal and mechanical stability and chemical resistance. Their response to ultraviolet (UV) irradiation is of further interest in high-value applications such as spacecraft technology and electronics packaging. In this work, we investigated the effect of 172-nm UV xenon excimer lamp irradiation on samples of pyromellitimido-oxydianiline (PMDA-ODA) commercial films in the absence of oxygen. The average irradiance received at the sample position was 90 mW/cm2, and the total radiation dosage varied from 0 to 64 J/cm2. X-Ray photoelectron spectroscopy, time-of-flight-secondary ion mass spectrometry, atomic force microscopy, and contact angle measurements were used to characterize the effect. Calculated UV-visible spectroscopy absorption spectra were obtained using the ZINDO//B3LYP/3-21G method to give an indication of which orbitals are involved in the transitions near 172 nm. The reactivity of the different UV-treated PI samples toward nitrogen-borne heptafluorodecene vapor was then investigated using the above techniques. Grafting reactions occurred on the surface of the photochemically activated polymer. This study explored the potential for modification of PI surfaces using UV-light-assisted grafting to impart valuable functionalities.

One-pot synthesis of secondary amines from alcohols and nitroarenes on TiO2 loaded with Pd nanoparticles under UV irradiation

2015 ◽  
Vol 39 (4) ◽  
pp. 2467-2473 ◽  
Author(s):  
Kaliyamoorthy Selvam ◽  
Hirokatsu Sakamoto ◽  
Yasuhiro Shiraishi ◽  
Takayuki Hirai
Keyword(s):  
Uv Irradiation ◽  
Uv Light ◽  
Pd Nanoparticles ◽  
Catalytic Reactions ◽  
Quantitative Yield ◽  
Secondary Amines ◽  
One Pot ◽  
One Pot Synthesis

TiO2 loaded with Pd nanoparticles, when irradiated by UV light in alcohols with nitroarenes, successfully produces the corresponding secondary amines with almost quantitative yield, via tandem photocatalytic and catalytic reactions.

scholarly journals Occurrence of heavy metals and contaminants on the surface of adjacent rivers

2016 ◽  
Vol 15 (1) ◽  
pp. 50-57
Author(s):  
Warita Alves de Melo ◽  
Carla Afonso da Silva Bitencourt Braga ◽  
Lilian Carla Carneiro
Keyword(s):  
Heavy Metals ◽  
Uv Irradiation ◽  
Rainy Season ◽  
Uv Light ◽  
Stream Water ◽  
Environmental Stressors ◽  
National Council ◽  
Thermotolerant Coliforms ◽  
Quantitative Analyses ◽  
Sanitary Conditions

Water is fundamental to the survival of living beings. It registers every impact and can function as an indicator of environmental stressors. Our objective in the current study was to assess the sanitary conditions of the waters in the Açude, Maria Lucinda and Santa Rosa streams. This was done by checking pH, running quantitative analyses of heavy metals and testing for total coliforms. The effect of ultraviolet (UV) rays on samples positive for coliforms was evaluated. The average pH of the streams ranged between 4 and 7 and changed between drought and rainy season conditions. Chromium and nickel values were above those permitted by the Brazilian National Council on the Environment, CONAMA. In the dry season, zinc values were above those established by CONAMA for waterbodies of Classes 1 and 2. Thermotolerant coliforms were present in all samples collected and above permitted values. After exposing the bacteria to UV light, it was noted that UV irradiation was unable to decrease the bacteria count. Ninety residents who use stream water were interviewed: 24% of interviewees said they use the waters of the Açude and Mary Lucinda streams and along the Santa Rosa stream, 95% of inhabitants said they use the water.

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