scholarly journals Removal of Meropenem by using Lemna minor

2021 ◽  
Vol 30 (3) ◽  
pp. 485-495
Author(s):  
Noora Saad ◽  
Samara Al-Dulaimi
Keyword(s):  
Lemna Minor ◽  
Experimental Testing ◽  
Degradation Mechanism ◽  
Oxygen Demand ◽  
Degradation Behavior ◽  
Order Model ◽  
Pharmaceutical Substances ◽  
Pharmaceutical Contamination ◽  
Contamination Levels

In this paper we presented a case study about the removal of a pharmaceutical contamination (in this case Meropenem) from the environment using organic natural substance (in this case study is Lemna minor). The study proved the efficiency of the used material to remove the contamination of three specific contamination levels of Meropenem. The experimental testing proved the concept, the effect on two vital measures (the chemical oxygen demand – COD, and the root length), which showed improvement in both measures. The degradation mechanism was proven to be not arbitrary by testing the degradation behavior measured practically to four kinetic models. The practical work was found to fit perfectly with the Grau second order model as the simulation work included in the paper shows. Based on this study it can be proven that the dangerous chemicals resulted from the residue of a pharmaceutical substances can be removed efficiently using a totally natural environmental friendly material.

Side effects of cultured bacteria addition in wastewater collection system on plant operations – a case study

2012 ◽  
Vol 7 (1) ◽  
Author(s):  
Yanjin Liu ◽  
Giraldo Eugenio
Keyword(s):  
Energy Use ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Collection System ◽  
Oil And Grease ◽  
Odor Control ◽  
Plant Operations ◽  
Cultured Bacteria ◽  
Wastewater Collection

Cultured bacteria addition is one of the technologies used for odor control and FOG (fat, oil, and grease) removal in wastewater collection systems. This study investigated the efficiency of bacterial addition on wastewater odor control by conducting a set of full scale trials in a 60,000 cubic meter per day system for a period of two years. The objectives of this study were: (i) to identify factors that could impact wastewater treatment plant (WWTP) operations due to the effect of bacterial addition in the collection system, (ii) to estimate/understand the level of those impacts, and (iii) to present some interesting findings from the completed case study. The plant operation data before and during the bacterial addition were reviewed. The application of the cultured bacteria presented in the study was found to have significant impacts on the operation of the WWTP in terms of influent biological oxygen demand (BOD) and total suspended solids (TSS) loading, primary settling, sludge production, energy use, dissolved sulfides concentration, and methane production.

Impact of municipal solid waste dumpsites on trace metal contamination levels in the surrounding area: a case study in West Africa, Abidjan, Cote d’Ivoire

2021 ◽  
Author(s):  
Naminata Sangaré Soumahoro ◽  
N’guessan Louis Berenger Kouassi ◽  
Koffi Marcellin Yao ◽  
Edith Kouassi Kwa-Koffi ◽  
Aka Marcel Kouassi ◽  
...  
Keyword(s):  
West Africa ◽  
Trace Metal ◽  
Municipal Solid Waste ◽  
Solid Waste ◽  
Cote D'ivoire ◽  
Metal Contamination ◽  
Surrounding Area ◽  
Trace Metal Contamination ◽  
Contamination Levels

scholarly journals Degradation Behavior of Polymers Used as Coating Materials for Drug Delivery—A Basic Review

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1272
Author(s):  
Anita Ioana Visan ◽  
Gianina Popescu-Pelin ◽  
Gabriel Socol
Keyword(s):  
Drug Delivery ◽  
Degradation Mechanism ◽  
Degradation Behavior ◽  
Polymeric Coatings ◽  
Degradation Mechanisms ◽  
Coating Materials ◽  
Factors Affecting ◽  
Existing Problems ◽  
Future Performance ◽  
Measuring Techniques

The purpose of the work was to emphasize the main differences and similarities in the degradation mechanisms in the case of polymeric coatings compared with the bulk ones. Combined with the current background, this work reviews the properties of commonly utilized degradable polymers in drug delivery, the factors affecting degradation mechanism, testing methods while offering a retrospective on the evolution of the controlled release of biodegradable polymeric coatings. A literature survey on stability and degradation of different polymeric coatings, which were thoroughly evaluated by different techniques, e.g., polymer mass loss measurements, surface, structural and chemical analysis, was completed. Moreover, we analyzed some shortcomings of the degradation behavior of biopolymers in form of coatings and briefly proposed some solving directions to the main existing problems (e.g., improving measuring techniques resolution, elucidation of complete mathematical analysis of the different degradation mechanisms). Deep studies are still necessary on the dynamic changes which occur to biodegradable polymeric coatings which can help to envisage the future performance of synthesized films designed to be used as medical devices with application in drug delivery.

Use of DNVGL-RP-C203 for Determining the Fatigue Capacity of Connectors

2021 ◽  
Author(s):  
Anthony Muff ◽  
Anders Wormsen ◽  
Torfinn Hørte ◽  
Arne Fjeldstad ◽  
Per Osen ◽  
...  
Keyword(s):  
Finite Element ◽  
Fatigue Testing ◽  
Experimental Testing ◽  
High Strength ◽  
Element Model ◽  
Fatigue Analysis ◽  
Full Scale ◽  
The Finite Element Model

Abstract Guidance for determining a S-N based fatigue capacity (safe life design) for preloaded connectors is included in Section 5.4 of the 2019 edition of DNVGL-RP-C203 (C203-2019). This section includes guidance on the finite element model representation, finite element based fatigue analysis and determination of the connector design fatigue capacity by use of one of the following methods: Method 1 by FEA based fatigue analysis, Method 2 by FEA based fatigue analysis and experimental testing and Method 3 by full-scale connector fatigue testing. The FEA based fatigue analysis makes use of Appendix D.2 in C203-2019 (“S-N curves for high strength steel applications for subsea”). Practical use of Section 5.4 is illustrated with a case study of a fatigue tested wellhead profile connector segment test. Further developments of Section 5.4 of C203-2019 are proposed. This included acceptance criteria for use of a segment test to validate the FEA based fatigue analysis of a full-scale preloaded connector.

scholarly journals Dynamic Simulation of Petrochemical Wastewater Treatment Using Wastewater Plant Simulation Software

2018 ◽  
Vol 203 ◽  
pp. 03005
Author(s):  
Idzham Fauzi Mohd Ariff ◽  
Mardhiyah Bakir
Keyword(s):  
Simulation Model ◽  
Dynamic Simulation ◽  
Stable Condition ◽  
Oxygen Demand ◽  
Simulation Software ◽  
Petrochemical Plant ◽  
Dynamic Simulation Model ◽  
Plant Monitoring ◽  
Plant Simulation

A dynamic simulation model was developed, calibrated and validated for a petrochemical plant in Terengganu, Malaysia. Calibration and validation of the model was conducted based on plant monitoring data spanning 3 years resulting in a model accuracy (RMSD) for effluent chemical oxygen demand (COD), ammoniacal nitrogen (NH3-N) and total suspended solids (TSS) of ±11.7 mg/L, ±0.52 mg/L and ± 3.27 mg/L respectively. The simulation model has since been used for troubleshooting during plant upsets, planning of plant turnarounds and developing upgrade options. A case study is presented where the simulation model was used to assist in troubleshooting and rectification of a plant upset where ingress of a surfactant compound resulted in high effluent TSS and COD. The model was successfully used in the incident troubleshooting activities and provided critical insights that assisted the plant operators to quickly respond and bring back the system to normal, stable condition.

Integrated Strategy for Treatment of Winery Wastewaters Using Flocculation, Ozonation and Fenton’s Oxidation

2009 ◽  
Vol 12 (2) ◽  
Author(s):  
Rui C. Martins ◽  
Fernando J.R. Abegão ◽  
Adrián M.T. Silva ◽  
Rosa M. Quinta-Ferreira
Keyword(s):  
Suspended Solids ◽  
Oxygen Demand ◽  
Operational Cost ◽  
Adequate Treatment ◽  
Integration Strategy ◽  
Fenton’S Oxidation ◽  
Optimal Efficiency ◽  
Fenton's Oxidation ◽  
Ozonation Process

AbstractThe present research is based on a case-study involving the development of an adequate treatment for agro-effluents originating from wineries. Flocculation, Fenton’s oxidation and ozonation processes were investigated in order to define the best integration strategy that may conduce to optimal efficiency of degradation and operational cost. Chemical oxygen demand (COD), total suspended solids (TSS), and total organic carbon (TOC) were some of the parameters used to analyze the performance of these technologies. The higher COD and TSS removals (73% and 94% respectively) were achieved combining the ozonation treatment with the Fenton process. In addition, the respective cost of COD reduction is lower in this case, when compared with other alternatives. Flocculation revealed not to be needed since in the ozonation process the suspended solids are able to be degraded.

scholarly journals ACID ORANGE 52 DYE DEGRADATION BY ELECTROCATALYTIC PLUS PHOTOCATALYTIC TECHNIQUE AND INTERMEDIATES DETECTION

2018 ◽  
Vol 61 (4-5) ◽  
pp. 111
Author(s):  
Hui Zhao ◽  
Heng Zhong ◽  
Lei Sun ◽  
Alexander V. Nevsky ◽  
Dongsheng Xia
Keyword(s):  
Dye Degradation ◽  
Removal Rate ◽  
Degradation Mechanism ◽  
Oxygen Demand ◽  
Ionization Mass ◽  
Light Spectrum ◽  
Resource Saving ◽  
Acid Orange ◽  
Visible Part ◽  
Photocatalytic Processes

The degradation efficiency of Acid Orange 52 dye in an aqueous solutions using the combination of electrocatalytic and photocatalytic processes has been studied. Electrocatalytic and photocatalytic methods in practice reckon among advanced oxidation processes (AOPs). The effect of catalyst B dosage and irradiarion time on the rate of mentioned dye degradation was studied in the photocatalytic process. It was shown, that when Acid Orange 52 simulated dye wastewater was treated by electrocatalytic technique under optimal conditions with catalyst A, the decolorization treatment effect was 95 % in visible part of light spectrum (464 nm) and 38.6 % in ultraviolet part (270 nm), respectively. When the combined electrocatalytic-photocatalytic technique was processed with catalysts A and B, the color removal rate of dye could reach 99.3% (464 nm) and 91.5% (270 nm), respectively. The large amount of products of small mole weight was formed in the course of oxidation reaction. Moreover, the obtained values of chemical oxygen demand (COD) and total organic carbon (TOC) witnessed, that the combination of electrocatalytic and photocatalytic processes could significantly improve the biodegradability of dye as a whole．It was shown, that the removal rate of COD and TOC, respectively, were 54.3% and 72.8%. The reaction intermediates were determined by electrospray ionization-mass spectrometry (ESI-MS) analysis, and as a result, the probable degradation mechanism (pathway) has been proposed. The results of the work may be useful as theoretical bases for designing effective resource-saving, technically efficient and economically sound wastewater treatment systems, containing hardly biodegradable azo dyes.Forcitation:Zhao H., Zhong H., Sun L., Xia D., Nevsky A.V. Acid Orange 52 dye degradation by electrocatalytic plus photocatalytic technique and intermediates detection. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 4-5. P. 111-118

Degradation behavior and degradation mechanism of bridged-grain polycrystalline silicon thin film transistors under AC gate bias stress

2017 ◽  
Vol 32 (2) ◽  
pp. 91-96
Author(s):  
张猛 ZHANG Meng ◽  
夏之荷 XIA Zhi-he ◽  
周玮 ZHOU Wei ◽  
陈荣盛 CHEN Rong-sheng ◽  
王文 WONG Man ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Film Transistors ◽  
Polycrystalline Silicon ◽  
Degradation Mechanism ◽  
Gate Bias ◽  
Degradation Behavior ◽  
Silicon Thin Film ◽  
Bias Stress ◽  
Gate Bias Stress

Organic Contamination of Silicon Wafer in Clean Room Air and its Impact to Gate Oxide Integrity

1997 ◽  
Vol 477 ◽  
Author(s):  
D. Imafuku ◽  
W. Mizubayashi ◽  
S. Miyazaki ◽  
M. Hirose ◽  
Y. Wakayama ◽  
...  
Keyword(s):  
Silicon Wafer ◽  
Degradation Mechanism ◽  
Gate Oxide ◽  
Contamination Level ◽  
Degradation Behavior ◽  
Clean Room ◽  
Organic Contamination ◽  
Organic Adsorbates ◽  
Wafer Surfaces ◽  
Dielectric Degradation

ABSTRACTOrganic adsorbates on silicon wafer surfaces exposed to superclean room air were measured to evaluate organic contamination level of silicon wafers stored in a clean bench up to 180min. Such Si wafers were thermally oxidized and the dielectric degradation behavior were systematically investigated. It is found that a carbon contamination level of half a monolayer influences the charge to quasi-breakdown although the degradation mechanism itself remains unchanged.

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