The Use of UV Spectrophotometry for Rapid Site Organic Pollution Diagnosis

2002 ◽  
pp. 193-198
Author(s):  
E. Steyer ◽  
L. Belkessam ◽  
A. Laboudigue ◽  
P. Dengis ◽  
A. Copin
Keyword(s):  
Organic Pollution ◽  
Uv Spectrophotometry

Quantitative Determination of Amlodipine Besylate in Tablets of Combined Antihypertensive Preparations by UV Spectrophotometry

2018 ◽  
Vol 12 (3) ◽  
pp. 14-18
Author(s):  
Sirazhudin Dzh. Mekhtikhanov ◽  
◽  
Dzhamilya P. Babaeva ◽  
Kusum M. Magomedova ◽  
Patimat A. Gamzatova ◽  
...  
Keyword(s):  
Quantitative Determination ◽  
Uv Spectrophotometry ◽  
Amlodipine Besylate

Long Term Monitoring of the Macrobenthos of the Upper Clyde Estuary

1984 ◽  
Vol 16 (5-7) ◽  
pp. 359-373 ◽  
Author(s):  
Anne R Henderson
Keyword(s):  
Water Quality ◽  
Seasonal Variation ◽  
Organic Pollution ◽  
Long Term Changes ◽  
Pollution Loading ◽  
Faunal Density ◽  
History Of ◽  
Long Term Monitoring ◽  
Term Monitoring

The sublittoral macrobenthic invertebrate populations of the Upper Clyde Estuary are described. The estuary has a long history of organic pollution. The long term changes in species composition, faunal density and dominance patterns between 1974 and 1980 are presented. The fauna is dominated by brackish, pollution tolerant oligochaetes and polychaetes. Fluctuations in populations can be related to both seasonal variation in environmental conditions and long term improvements in water quality through a reduction in pollution loading to the estuary.

Activated sludge plant facing grape harvest period – a case study

1996 ◽  
Vol 34 (11) ◽  
pp. 25-32 ◽  
Author(s):  
P. Chudoba ◽  
R. Pujol
Keyword(s):  
Activated Sludge ◽  
Municipal Wastewater ◽  
Treatment Plant ◽  
Organic Pollution ◽  
Worst Case ◽  
Wine Production ◽  
Original Solution ◽  
Treated Effluent ◽  
Nominal Capacity ◽  
Sludge Settleability

Most of municipal activated sludge plants located in wine production regions receive winery wastewaters during the grape harvest period which lasts usually only a few weeks. A drastic increase in organic pollution (COD, BOD) during this period generates a temporary overloading, resulting very often in biological problems such as decreased sludge settleability, sludge floc disintegration, increased SS concentration in treated effluent and in the worst case a complete plant failure. In order to work satisfactorily even during those temporary overloading periods, the plant has to be oversized. This strategy is rather costly, because such a plant has to run below its nominal capacity during a major part of the year. An original solution has been proposed and successfully tested at a municipal wastewater treatment plant in Eguisheim, France. The proposed technique is based on the addition of a mineral material with a low particle size, whose presence positively influences the physical behaviour of the sludge and will allow the nominal capacity of the plant to be surpassed without any important modification. The modification of the sludge structure around the added powdered material improved significantly the sludge settleability (DSVI< 160 ml/g) and enabled the plant to treat organic pollution several times higher than the nominal level.

A simple test for monitoring biodegradable industrial pollution in a receiving stream

1999 ◽  
Vol 39 (10-11) ◽  
pp. 221-224 ◽  
Author(s):  
Jana Zagorc-Končan ◽  
J. Šömen
Keyword(s):  
Hazard Assessment ◽  
Industrial Pollution ◽  
Self Regulation ◽  
Oxygen Demand ◽  
Organic Pollution ◽  
Organic Substances ◽  
Simple Test ◽  
Industrial Pollutants ◽  
Model Substances ◽  
Receiving Stream

Microbial purification capacity is an important factor in natural self-regulation in water. Evaluating the fate of biodegradable organic pollution downstream from the discharge seems an appropriate way to follow the effect of pollution and its hazard assessment, which dictates the needed sanitation measures. We suggest a simple test for such monitoring. A modification of the additional oxygen demand test, standardised in Ausgewählte Methoden der Wasseruntersuchung, was applied in two river case studies. The additional oxygen demand is a measure of the capability and rate of biodegradation of known organic substance as well as of the amount and activity of heterotrophic organisms in the river. The original test using peptone and glucose as additional feedings of BOD samples was modified by the use of other organic biodegradable model substances characteristic for individual industrial pollutants. The test was found to be an excellent indicator of adapted microorganisms, which are essential for the biodegradation of the appointed organic substances downstream of their discharge into the receiving stream.

Recent Advances in Heterostructured Photocatalysts for Degradation of Organic Pollutants.

2020 ◽  
Vol 17 ◽  
Author(s):  
Chen-Jing Sun ◽  
Li-Ping Zhao ◽  
Rui Wang
Keyword(s):  
Organic Pollutants ◽  
High Efficiency ◽  
Separation Efficiency ◽  
Organic Pollution ◽  
Utilization Rate ◽  
Type I ◽  
Human Beings ◽  
Global Challenge ◽  
Global Environmental ◽  
High Efficient

: With the development of industrialization, the global environmental pollution and energy crisis are becoming increasingly serious. Organic pollutants pose a serious health threat to human beings and other organisms. The removal of organic pollutants in environment has become a global challenge. The photocatalytic technology has been widely used in the degradation of organic pollutants with its characteristics of simple process, high efficiency, thorough degradation and no secondary pollution. However, the single photocatalyst represented by TiO2 has disadvantages of low light utilization rate and high recombination rate of photocarriers. Building heterojunction is considered one of the most effective methods to enhance the photocatalytic performance of single photocatalyst, which can improve the separation efficiency of photocarriers and utilization of visible light. The classical heterojunction can be divided into four different cases: type I, typeⅡ, p–n heterojunctions and Z-scheme junction. In this paper, the recent progress in the treatment of organic pollution by heterostructure photocatalysts is summarized and the mechanism of heterostructure photocatalysts for the treatment of organic pollutants is reviewed. It is expected that this paper can deepen the understanding of heterostructure photocatalysts and provide guidance for high efficient photocatalytic degradation of organic pollutants in the future.

scholarly journals Impact of aquaculture on distribution of dissolved organic matter in coastal Jeju Island, Korea, based on absorption and fluorescence spectroscopy

2021 ◽  
Author(s):  
Jeonghyun Kim ◽  
Yeseul Kim ◽  
Sung Eun Park ◽  
Tae-Hoon Kim ◽  
Bong-Guk Kim ◽  
...  
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Fluorescence Spectroscopy ◽  
Dissolved Organic Matter ◽  
Coastal Water ◽  
Coastal Region ◽  
Principal Component ◽  
Distribution Patterns ◽  
Organic Pollution ◽  
Jeju Island

AbstractIn Jeju Island, multiple land-based aquafarms were fully operational along most coastal region. However, the effect of effluent on distribution and behaviours of dissolved organic matter (DOM) in the coastal water are still unknown. To decipher characteristics of organic pollution, we compared physicochemical parameters with spectral optical properties near the coastal aquafarms in Jeju Island. Absorption spectra were measured to calculate the absorption coefficient, spectral slope coefficient, and specific UV absorbance. Fluorescent DOM was analysed using fluorescence spectroscopy coupled with parallel factor analysis. Dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) were measured using high-temperature catalytic oxidation. The DOC concentration near the discharge outlet was twice higher than that in natural groundwater, and the TDN concentration exponentially increased close to the outlet. These distribution patterns indicate that aquafarms are a significant source of DOM. Herein, principal component analysis was applied to categorise the DOM origins. There were two distinct groups, namely, aquaculture activity for TDN with humic-like and high molecular weights DOM (PC1: 48.1%) and natural biological activity in the coastal water for DOC enrichment and protein-like DOM (PC2: 18.8%). We conclude that the aquafarms significantly discharge organic nitrogen pollutants and provoke in situ production of organic carbon. Furthermore, these findings indicate the potential of optical techniques for the efficient monitoring of anthropogenic organic pollutants from aquafarms worldwide.

scholarly journals Diatom Algae-Indicators of Water Quality in the Lower Zarafshan River, Uzbekistan

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 358
Author(s):  
Sophia Barinova ◽  
Karomat Mamanazarova
Keyword(s):  
Water Quality ◽  
Organic Pollution ◽  
Middle Part ◽  
Pollution Indices ◽  
Distribution Analysis ◽  
State Monitoring ◽  
Ecological Mapping ◽  
Semi Arid Region ◽  
Species Richness And Abundance ◽  
Toxicity Indices

This work is the first, the purpose of which was a comprehensive assessment of the ecological state of the lower reaches of the Zarafshan River using bioindication of water quality by diatoms based on species’ ecological preferences, pollution indices, statistics, and ecological mapping. A total of 198 species and subspecies of diatoms were first identified from 195 samples collected four times a year at six sites in the lower reaches of the Zarafshan River in 2009–2015. The richest species were Cymbella, Navicula, and Nitzschia. Pleurosira laevis, resistant to salinity, was first found in aquatic habitats in Uzbekistan. Bioindicators of nine environmental variables make up 91% of the list. Distribution analysis of variables, pollution indices (SLA—SládečDek index of saprobity), and toxicity indices (WESI—Water Ecosystem State Index) show increases in salinity, turbidity, and decreases in organic pollution downstream. The source of acidification can be the Navoi region. We found an increase in the ability to self-purify with an increase in species richness and abundance of diatoms in the lower part of Zarafshan. Thus, the ecosystem of the studied part of the river successfully copes with the incoming pollution from the middle part of Zarafshan and demonstrates some stability and successful self-purification with a water quality class of 2–3. The first studied lower reaches of the ecosystem of the Zarafshan River using bioindicators, statistics, and ecological mapping show that the problem of aridization in Central Asia does not necessarily lead to degradation of the river ecosystem and an increase in pollution, but with rational water use can improve water quality and self-purification processes. Hence, diatoms can be good indicators of river water quality in a semi-arid region and reflect the climate and anthropogenic load change. We recommend that attention be paid to nutrient and turbidity management and to expand state monitoring points to the lower part of the river up to the Karakul region.

scholarly journals Simultaneous Estimation of Domperidone and Pantoprazole in Solid Dosage Form by UV Spectrophotometry

2006 ◽  
Vol 3 (3) ◽  
pp. 142-145
Author(s):  
P. Ravi Kumar ◽  
P. Bhanu Prakash ◽  
M. Murali Krishna ◽  
M. Santha Yadav ◽  
C. Asha Deepthi
Keyword(s):  
Simultaneous Equation ◽  
Simultaneous Equations ◽  
Simultaneous Estimation ◽  
Uv Spectrophotometry ◽  
Q Value ◽  
Value Analysis ◽  
Spectrophotometric Methods ◽  
Solid Dosage ◽  
Tablet Dosage

Domperidone is an antiemetic and pantoprazole is an antiulcer drug. Simple, precise, rapid and selective simultaneous equation and Q- analysis UV spectrophotometric methods have been developed for the simultaneous determination of domperidone and pantoprazole from combined tablet dosage forms. The methods involve solving of simultaneous equations and Q-value analysis based on measurement absorptivity at 216, 287 and 290 nm respectively. Linearity lies between 1-15 mcg/mL for domperidone and 0-50 mcg/mL for pantoprazole.

scholarly journals Three-component reaction involving isoquinoline and dimethyl acethylenedicarboxylate in the presence of indole: Theoretical and experimental investigations of the reaction mechanism

2021 ◽  
Vol 46 ◽  
pp. 146867832095686
Author(s):  
Mohammad Zakarianezhad ◽  
Sayyed Mostafa Habibi-Khorassani ◽  
Batoul Makiabadi ◽  
Elham Zeydabadi
Keyword(s):  
Reaction Mechanism ◽  
Potential Energy Surfaces ◽  
Reaction Rate ◽  
Product Configuration ◽  
Experimental Investigations ◽  
Uv Spectrophotometry ◽  
Three Component Reaction ◽  
Energy Surfaces ◽  
Theoretical Results ◽  
Reaction Rate Equation

The reaction kinetics among isoquinoline, dimethyl acetylenedicarboxylate, and indole (as NH-acid) were investigated using ultraviolet (UV) spectrophotometry. The reaction rate equation was obtained, the dependence of the reaction rate on different reactants was determined, and the overall rate constant ( kov) was calculated. By studying the effects of solvent, temperature, and concentration on the reaction rate, some useful information was obtained. A logical mechanism consistent with the experimental observations was proposed. Also, comprehensive theoretical studies were performed to evaluate the potential energy surfaces of all structures that participated in the reaction mechanism. Finally, the proposed mechanism was confirmed by the obtained results and the probable and logical reaction paths and also a correct product configuration were suggested based on the theoretical results.

scholarly journals Insights into the Antioxidant Mechanism of Newly Synthesized Benzoxazinic Nitrones: In Vitro and In Silico Studies with DPPH Model Radical

Antioxidants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1224
Author(s):  
Stefania Marano ◽  
Cristina Minnelli ◽  
Lorenzo Ripani ◽  
Massimo Marcaccio ◽  
Emiliano Laudadio ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Epr Spectroscopy ◽  
Point Of View ◽  
Uv Spectrophotometry ◽  
Design And Synthesis ◽  
Antioxidant Mechanism ◽  
Primary Mechanism ◽  
In Silico Studies ◽  
Wide Range

Synthetic nitrone spin-traps are being explored as therapeutic agents for the treatment of a wide range of oxidative stress-related pathologies, including but not limited to stroke, cancer, cardiovascular, and neurodegenerative diseases. In this context, increasing efforts are currently being made to the design and synthesis of new nitrone-based compounds with enhanced efficacy. The most researched nitrones are surely the ones related to α-phenyl-tert-butylnitrone (PBN) and 5,5-dimethyl-1-pyrroline N-oxide (DMPO) derivatives, which have shown to possess potent biological activity in many experimental animal models. However, more recently, nitrones with a benzoxazinic structure (3-aryl-2H-benzo[1,4]oxazin-N-oxides) have been demonstrated to have superior antioxidant activity compared to PBN. In this study, two new benzoxazinic nitrones bearing an electron-withdrawing methoxycarbonyl group on the benzo moiety (in para and meta positions respect to the nitronyl function) were synthesized. Their in vitro antioxidant activity was evaluated by two cellular-based assays (inhibition of AAPH-induced human erythrocyte hemolysis and cell death in human retinal pigmented epithelium (ARPE-19) cells) and a chemical approach by means of the α,α-diphenyl-β-picrylhydrazyl (DPPH) scavenging assay, using both electron paramagnetic resonance (EPR) spectroscopy and UV spectrophotometry. A computational approach was also used to investigate their potential primary mechanism of antioxidant action, as well as to rationalize the effect of functionalization on the nitrones reactivity toward DPPH, chosen as model radical in this study. Further insights were also gathered by exploring the nitrone electrochemical properties via cyclic voltammetry and by studying their kinetic behavior by means of EPR spectroscopy. Results showed that the introduction of an electron-withdrawing group in the phenyl moiety in the para position significantly increased the antioxidant capacity of benzoxazinic nitrones both in cell and cell-free systems. From the mechanistic point of view, the calculated results closely matched the experimental findings, strongly suggesting that the H-atom transfer (HAT) is likely to be the primary mechanism in the DPPH quenching.

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