scholarly journals Analytical Model and Numerical Analysis of Composite Wrap System Applied to Steel Pipeline

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6393
Author(s):  
Djouadi Djahida ◽  
Ghomari Tewfik ◽  
Maciej Witek ◽  
Mechri Abdelghani
Keyword(s):  
Composite Structures ◽  
Constitutive Models ◽  
Cost Effective ◽  
Composite Repair ◽  
Repair Technology ◽  
Repair Costs ◽  
Corrosion Defects ◽  
Industrial Standards ◽  
Composite Repairs

Composite overwraps are a cost-effective repair technology, appropriate for corrosion defects, dents, and gouges for both onshore and offshore steel pipelines. The main benefit of polymer-based sleeves is safe installation without taking the pipeline out of service. This paper presents a new calculation procedure proposed in the form of an algorithm for the sizing of composite repairs of corroded pipelines when the sleeve is applied at zero internal pressure. The main objective of the presented methodology is determination of the effective thickness of the composite repair without its overestimation or underestimation. The authors used a non-linear finite element method with constitutive models allowing analysis of the steel, putty, and composite structures. The validation of the results of numerical computations compared to the experimental ones showed an appropriate agreement. The numerical calculations were applied to compare the analytical results in relation to those obtained by the standards ASME PCC-2 or ISO/TS 24817. The comparison showed that the proposed solution confirmed its effectiveness in reducing the thickness of the sleeve significantly, thus, showing that the current industrial standards provide a considerably excessive composite wrap around the steel pipe corroded area, which leads to an unnecessary increase in the repair costs.

scholarly journals Precise Design and Analysis of Wet Layup Composite Repairs

1999 ◽  
Author(s):  
Greg Kress
Keyword(s):  
Composite Structures ◽  
Heat Sinks ◽  
Underlying Structure ◽  
Composite Repair ◽  
Processing Equipment ◽  
Analysis Techniques ◽  
Repair Materials ◽  
Physical Limitations ◽  
Composite Repairs

Abstract The increasing size and cost of composite structures combined with the increased loading requirements placed on such components has heightened the need for performing durable and thoroughly analyzed composite repairs. Precise applications of composite repairs possess many difficulties from both a maintenance and engineering standpoint. The composite repair engineer is often limited by the repair materials and processing equipment that are available, the data to define the loads placed on the structure, and physical limitations such as the inability to remove a panel from the aircraft, heat sinks, and underlying structure. This presentation describes the repair configuration, materials and analysis techniques for performing the precise design and analysis of wet layup composite repairs.”

Corncob Waste Based Adsorbent for Solid Phase Extraction of Tartrazine in Carbonated Drinks and Analytical Method using Ultra Performance Liquid Chromatography-Mass Spectrometry

2020 ◽  
Vol 16 (7) ◽  
pp. 924-932
Author(s):  
Yasmeen Mutlaq Ghazi Al Shamari ◽  
Saikh Mohammad Wabaidur ◽  
Abdulrahman Abdullah Alwarthan ◽  
Moonis Ali Khan ◽  
Masoom Raza Siddiqui
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Solid Phase Extraction ◽  
Solid Phase ◽  
Cost Effective ◽  
Ultra Performance Liquid Chromatography ◽  
Phase Extraction ◽  
Food Dye ◽  
Hyphenated Technique

Background : A new method has been developed for the determination of food dye tartrazine in soft drinks. Tartrazine is determined by hyphenated technique Ultra Performance Liquid Chromatography coupled with Mass spectrometry. The solid-phase extraction was used for the extraction of tartrazine. Methods: For the LC-MS analysis of tartrazine acetonitrile, water (80:20) was used as a mobile phase whereas, the C-18 column was selected as the stationary phase. The chromatographic run was allowed for 1 min. The adsorbent of the solid-phase extraction was synthesized from the waste corn cob. Results: Method found to be linear in the range of 0.1 mg L-1 - 10 mg L-1, limits of detection and quantitation were found to be 0.0165 mgL-1 and 0.055 mgL-1, respectively. Tartrazine, in the real sample, was found to be 20.39 mgL-1 and 83.26 mgL-1. Conclusion: The developed UPLC-MS method is rapid, simple, precise and can be used for the quantitative analysis of tartrazine. The solid-phase extraction also involves a cost-effective procedure for extraction as it does not involve the commercial cartridge.

scholarly journals Pitfalls in the Immunochemical Determination of β‑Lactam Antibiotics in Water

Antibiotics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 298
Author(s):  
Alexander Ecke ◽  
Rudolf J. Schneider
Keyword(s):  
Limit Of Detection ◽  
Cost Effective ◽  
Enzyme Linked Immunosorbent Assay ◽  
Degree Of Hydrolysis ◽  
Site Analysis ◽  
Antibody Recognition ◽  
Immunochemical Determination ◽  
Key Factor ◽  
Lactam Ring

Contamination of waters with pharmaceuticals is an alarming problem as it may support the evolution of antimicrobial resistance. Therefore, fast and cost-effective analytical methods for potential on-site analysis are desired in order to control the water quality and assure the safety of its use as a source of drinking water. Antibody-based methods, such as the enzyme-linked immunosorbent assay (ELISA), can be helpful in this regard but can also have certain pitfalls in store, depending on the analyte. As shown here for the class of β-lactam antibiotics, hydrolysis of the β‑lactam ring is a key factor in the immunochemical analysis as it influences antibody recognition. With the antibody used in this study, the limit of detection (LOD) in the immunoassay could be significantly reduced by hydrolysis for the five tested penicillins, with the lowest LOD for carbenicillin (0.2 nmol/L) and the greatest impact on penicillins G and V (reduction by 85%). In addition to enhanced quantification, our strategy also provides access to information about the degree of hydrolysis in water samples as shown for the most abundant penicillin amoxicillin.

Determination of a Rubber-Like Material Model as an Inverse Problem

2011 ◽  
Vol 70 ◽  
pp. 225-230 ◽  
Author(s):  
Agnieszka Derewonko ◽  
Andrzej Kiczko
Keyword(s):  
Selection Process ◽  
Axial Stress ◽  
Constitutive Models ◽  
Material Model ◽  
Polyester Fabric ◽  
Point Of View ◽  
Air Cushion ◽  
Ill Conditioning ◽  
Stress States

The purpose of this paper is to describe the selection process of a rubber-like material model useful for simulation behaviour of an inflatable air cushion under multi-axial stress states. The air cushion is a part of a single segment of a pontoon bridge. The air cushion is constructed of a polyester fabric reinforced membrane such as Hypalon®. From a numerical point of view such a composite type poses a challenge since numerical ill-conditioning can occur due to stiffness differences between rubber and fabric. Due to the analysis of the large deformation dynamic response of the structure, the LS-Dyna code is used. Since LS-Dyna contains more than two-hundred constitutive models the inverse method is used to determine parameters characterizing the material on the base of results of the experimental test.

scholarly journals Multivariate empirical mode decomposition–based structural damage localization using limited sensors

2021 ◽  
pp. 107754632110069
Author(s):  
Sandeep Sony ◽  
Ayan Sadhu
Keyword(s):  
Empirical Mode Decomposition ◽  
Structural Damage ◽  
Cost Effective ◽  
Threshold Value ◽  
Damage Localization ◽  
Time Frequency ◽  
Multivariate Empirical Mode Decomposition ◽  
Percentage Difference ◽  
Mode Decomposition

In this article, multivariate empirical mode decomposition is proposed for damage localization in structures using limited measurements. Multivariate empirical mode decomposition is first used to decompose the acceleration responses into their mono-component modal responses. The major contributing modal responses are then used to evaluate the modal energy for the respective modes. A damage localization feature is proposed by calculating the percentage difference in the modal energies of damaged and undamaged structures, followed by the determination of the threshold value of the feature. The feature of the specific sensor location exceeding the threshold value is finally used to identify the location of structural damage. The proposed method is validated using a suite of numerical and full-scale studies. The validation is further explored using various limited measurement cases for evaluating the feasibility of using a fewer number of sensors to enable cost-effective structural health monitoring. The results show the capability of the proposed method in identifying as minimal as 2% change in global modal parameters of structures, outperforming the existing time–frequency methods to delineate such minor global damage.

scholarly journals Immobilization-Free Electrochemical Sensor Coupled with a Graphene-Oxide-Based Aptasensor for Glycated Albumin Detection

Biosensors ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 85
Author(s):  
Wassa Waiwinya ◽  
Thitirat Putnin ◽  
Dechnarong Pimalai ◽  
Wireeya Chawjiraphan ◽  
Nuankanya Sathirapongsasuti ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Electrochemical Sensor ◽  
Detection Method ◽  
Limit Of Detection ◽  
Glycated Albumin ◽  
Cost Effective ◽  
Logarithmic Scale ◽  
Electrochemical Aptasensor ◽  
Alternative Approach

An immobilization-free electrochemical sensor coupled with a graphene oxide (GO)-based aptasensor was developed for glycated human serum albumin (GHSA) detection. The concentration of GHSA was monitored by measuring the electrochemical response of free GO and aptamer-bound GO in the presence of glycated albumin; their currents served as the analytical signals. The electrochemical aptasensor exhibited good performance with a base-10 logarithmic scale. The calibration curve was achieved in the range of 0.01–50 µg/mL. The limit of detection (LOD) was 8.70 ng/mL. The developed method was considered a one-drop measurement process because a fabrication step and the probe-immobilization process were not required. This simple sensor offers a cost-effective, rapid, and sensitive detection method, and could be an alternative approach for determination of GHSA levels.

scholarly journals Paper-based potentiometric sensing devices modified with chemically reduced graphene oxide (CRGO) for trace level determination of pholcodine (opiate derivative drug)

RSC Advances ◽  
2021 ◽  
Vol 11 (20) ◽  
pp. 12227-12234
Author(s):  
Hisham S. M. Abd-Rabboh ◽  
Abd El-Galil E. Amr ◽  
Elsayed A. Elsayed ◽  
Ahmed Y. A. Sayed ◽  
Ayman H. Kamel
Keyword(s):  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Cost Effective ◽  
Trace Level ◽  
Ion Sensing ◽  
Reduced Graphene ◽  
Chemically Reduced Graphene Oxide ◽  
Trace Level Determination ◽  
Analytical Device

Robust, reliable and cost-effective paper-based analytical device for potentiometric pholcodine (opiate derivative drug) ion sensing has been prepared and characterized.

Quantum Dots as Components of Electrochemical Sensing Platforms for the Detection of Environmental and Food Pollutants: a Review

2017 ◽  
Vol 100 (4) ◽  
pp. 950-961 ◽  
Author(s):  
María Pedrero ◽  
Susana Campuzano ◽  
José M Pingarrón
Keyword(s):  
Quantum Dots ◽  
Signal Amplification ◽  
Cost Effective ◽  
Ease Of Use ◽  
Electrochemical Sensing ◽  
Multiplexed Detection ◽  
Sensing Platforms ◽  
Target Analytes

Abstract The determination of organic and inorganic environmental and food pollutants is a key matter of concern in analytical chemistry due to their effects as a serious threat to human health. Focusing on this issue, several methodologies involving the use of nanostructured electrochemical platforms have been recently reported in the literature. Among these methods, those employing the use of quantum dots (QDs) stand out because of features such as signal amplification, good reproducibility and selectivity, and the possibility for multiplexed detection, and because they preserve the outstanding characteristics of electrochemical methodologies with respect to simplicity, ease-of-use, and cost-effective instrumentation. This review describes recent electrochemical strategies, in which design QDs play a key role, for the determination of pollutants in food and environmental samples. The particular role of QDs in the reported methodologies, their preparation, and the electrochemical platform design, as well as the advantages that QDs provide in the analysis of target analytes, are critically discussed.

Sign in / Sign up

Export Citation Format

Share Document