Model Development for Energy dissipation over Gabion Stepped Weirs using GEP and GMDH techniques

2021 ◽  
Author(s):  
Ajmal Hussain ◽  
Mujib Ahmad Ansari ◽  
Md Nisar Ahmed ◽  
Faisal Ahmad ◽  
Jahangeer Jahangeer
Keyword(s):  
Energy Dissipation ◽  
Gene Expression Programming ◽  
Model Development ◽  
Cost Effective ◽  
Relative Energy ◽  
Group Method ◽  
Regression Equations ◽  
Aquatic Life ◽  
Flow Energy ◽  
Physical And Chemical

A Gabion stepped weir is a permeable weir that consists of a gabion box filled with stone aggregates. It is cost effective structure used for the dissipation of water flow energy from upstream to downstream. Gabion weir also allows the movement of aquatic life and transportation of physical and chemical substances present in water. In this study, energy dissipation in terms of inverse relative energy dissipation (IRED) over gabion stepped weir has been studied. It is observed that the existing predictor does not give a reasonable estimate for IRED. Therefore, the data have been reanalysed to develop a generalized regression equation for IRED. Generalized models using Gene Expression Programming (GEP) and Group Method of Data Handling (GMDH) were also developed. The predictions based on GMDH model(R=0.979,E=0.96 and RMSE=0.314) were found more satisfactory than those given by traditional regression equations(R=0.929,E=0.91 and RMSE=0.557) as well as the GEP model(R=0.959,E=0.94 and RMSE=0.476).

FLOW AND ENERGY DISSIPATION OVER ON FLAT AND POOLED STEPPED SPILLWAY

2016 ◽  
Vol 78 (8) ◽  
Author(s):  
Denik Sri Krisnayanti ◽  
Soehardjono Soehardjono ◽  
Very Dermawan ◽  
Mohammad Sholichin
Keyword(s):  
Energy Dissipation ◽  
Energy Loss ◽  
Froude Number ◽  
Relative Energy ◽  
Stepped Spillway ◽  
Dissipation Energy ◽  
Stepped Spillways ◽  
Flow Energy ◽  
Physical Study ◽  
Roughness Elements

The stepped spillway has increasingly become effective energy dissipation. The stepped spillway has been accepted to be the most powerful hydraulic structure to dissipate large flow energy downstream from spillway crest. The steps act as roughness elements significantly increase the dissipation energy rate. The physical study has performed on flat and pooled stepped spillways with a slope spillway    (θ = 45˚) and number of steps (N): 20 and 40. The experiments were conducted for ten Froude number (Fr) run ranging from 1.117 to 9.909 with 0.700<yc/h<3.00. The focus of research to investigate the relationship between relative energy losses in skimming flow performance against Froude number on various stepped. The effect of number of steps is evident when the relative energy loss increases with the number of steps. In addition, the relative energy loss of flow on pooled steps is dissipating more energy than flat steps.

scholarly journals Synthesis and Conductivity Studies of Poly(Methyl Methacrylate) (PMMA) by Co-Polymerization and Blending with Polyaniline (PANi)

Polymers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1939
Author(s):  
Helyati Abu Hassan Shaari ◽  
Muhammad Mahyiddin Ramli ◽  
Mohd Nazim Mohtar ◽  
Norizah Abdul Rahman ◽  
Azizan Ahmad
Keyword(s):  
Methyl Methacrylate ◽  
Mechanical Stability ◽  
Chemical Properties ◽  
Cost Effective ◽  
Poly Methyl Methacrylate ◽  
Conducting Materials ◽  
Potential Applications ◽  
Polymerization Condition ◽  
Physical And Chemical ◽  
And Chemical Properties

Poly(methyl methacrylate) (PMMA) is a lightweight insulating polymer that possesses good mechanical stability. On the other hand, polyaniline (PANi) is one of the most favorable conducting materials to be used, as it is easily synthesized, cost-effective, and has good conductivity. However, most organic solvents have restricted potential applications due to poor mechanical properties and dispersibility. Compared to PANi, PMMA has more outstanding physical and chemical properties, such as good dimensional stability and better molecular interactions between the monomers. To date, many research studies have focused on incorporating PANi into PMMA. In this review, the properties and suitability of PANi as a conducting material are briefly reviewed. The major parts of this paper reviewed different approaches to incorporating PANi into PMMA, as well as evaluating the modifications to improve its conductivity. Finally, the polymerization condition to prepare PMMA/PANi copolymer to improve its conductivity is also discussed.

Investigation of the flow energy dissipation law in a centrifugal impeller in pump mode

2021 ◽  
pp. 095765092110349
Author(s):  
Ran Tao ◽  
Puxi Li ◽  
Zhifeng Yao ◽  
Ruofu Xiao
Keyword(s):  
Energy Dissipation ◽  
Flow Rate ◽  
Performance Estimation ◽  
Vortical Flow ◽  
Wall Friction ◽  
Negative Slope ◽  
Centrifugal Impeller ◽  
Pump Mode ◽  
Flow Energy ◽  
Flow Interaction

Centrifugal impeller is usually designed for water pumping. Fluid get energy from impeller but also lose energy when passing through it. To improve the efficiency and have a better operation stability, it is necessary to understand the flow energy dissipation in centrifugal impeller in pump mode. In this case, a thermodynamic analysis is conducted on a model centrifugal pump unit based on computational fluid dynamics (CFD) simulation. Typical performance curve is found with a positive-slope efficiency curve and a negative-slope head curve. With the decreasing of flow rate, both the impeller head and the flow energy dissipation (FED) will rise up. The FED is found related to the flow regime. The complex undesirable flow pattern induces high FED under off-design conditions especially at very small partial-load. Based on the visualization, FED is found with two main sources including the wall friction and the flow interaction. At over-load and design-load, the wall friction induced FED is dominant. With the decreasing of flow rate, flow interaction induced FED becomes dominant. The typical strong FED sites are found related to the striking, separation, merging and interaction of both smooth flow and vortical flow. The FED analysis will correlate the pump performance estimation and guide the design.

Biosynthesis of selenium nanoparticles by Aspergillus flavus and Candida albicans and comparison of their effects with antifungal drugs

2021 ◽  
Author(s):  
Mahdi Hosseini Bafghi ◽  
Razieh Nazari ◽  
Majid Darroudi ◽  
Mohsen Zargar ◽  
Hossein Zarrinfar
Keyword(s):  
Candida Albicans ◽  
Aspergillus Flavus ◽  
Fungal Pathogens ◽  
Chemical Properties ◽  
Cost Effective ◽  
Antifungal Drugs ◽  
Selenium Nanoparticles ◽  
Fungal Strains ◽  
Vis Spectroscopy ◽  
Physical And Chemical

Abstract Biosynthesis of nanoparticles can stand as a replacement for the available chemical and physical methods by offering new procedures as green syntheses that have proved to be simple, biocompatible, safe, and cost-effective. Considering how nanoparticles with a size of 1 to 100 nanometers contain unique physical and chemical properties, recent reports are indicative of observing the antifungal qualities of selenium nanoparticles (Se-NPs). Recently, the observance of antifungal resistance towards different species of these fungi is often reported. Therefore, due to the antifungal effects of biological nanoparticles, this study aimed to investigate the exertion of these nanoparticles and evaluate their effects on the growth of fungal pathogens. Se-NPs were biosynthesized by the application of wet reduction method, which included specific concentrations of Aspergillus flavus and Candida albicans. The presence of nanoparticles was confirmed by methods such as UV-Vis spectroscopy, FT-IR analysis, and FESEM electron microscope that involved FESEM and EDAX diagram. The fungal strains were cultured in sabouraud dextrose agar medium to perform the sensitivity test based on the minimum inhibitory concentration (MIC) method in duplicate. The utilization of Se-NPs at concentrations of 1 µg/ ml and below resulted in zero growth of fungal agents. However, their growth was inhibited by antifungal drugs at concentrations of 2 µg/ ml and higher. Based on the obtained results, biological nanoparticles produced by fungal agents at different concentrations exhibited favorable inhibitory effects on the growth of fungal strains.

scholarly journals Hybrid Finite Element Method Development for Offshore Structures’ Calculation with the Implementation of Industry Standards

2019 ◽  
Vol 26 (4) ◽  
pp. 90-100
Author(s):  
Jacek Łubiński ◽  
Henryk Olszewski
Keyword(s):  
Finite Element ◽  
Method Development ◽  
Structural Model ◽  
Model Development ◽  
Steel Structures ◽  
Cost Effective ◽  
Offshore Structures ◽  
Wind Loading ◽  
Hybrid Finite Element Method ◽  
Industry Standards

Abstract In the design process of offshore steel structures, it is typical to employ commercial calculation codes in which simulation and evaluation of results are performed on the basis of the available standards (e.g. API, DNV, Lloyds). The modeling and solution rely on finite element methods and cover the simulation of the structure’s properties along with the influence of the marine environment – sea currents, wave and wind loading, as well as the influence of vibrations, buoyancy and accompanying mass of water. Both commercial and open source mathematical modeling software which is available nowadays allows for cost effective and flexible implementation of advanced models for offshore industrial structures with high level of credibility and safety. The models can be built to suit task-specific requirements and evaluated on the basis of the selected criterial system best suited to the needs of the customer. Examples of methodology for environmental and structural model development are presented, along with simulation results covering a wide scope of data, ranging from stress and deformation to resonant characteristics and issues of technological feasibility.

scholarly journals Enzymes Involved in Plastic Degradation

2021 ◽  
pp. 95-110
Author(s):  
S.Z.Z. Cobongela
Keyword(s):  
Polyethylene Terephthalate ◽  
Synthetic Polymers ◽  
Chemical Degradation ◽  
Natural Resistance ◽  
Aquatic Life ◽  
Carbon Backbone ◽  
Catabolic Enzymes ◽  
Plastic Degradation ◽  
Global Increase ◽  
Physical And Chemical

The global increase in production of plastic and accumulation in the environment is becoming a major concern especially to the aquatic life. This is due to the natural resistance of plastic to both physical and chemical degradation. Lack of biodegradability of plastic polymers is linked to, amongst other factors, the mobility of the polymers in the crystalline part of the polyesters as they are responsible for enzyme interaction. There are significantly few catabolic enzymes that are active in breaking down polyesters which are the constituents of plastic. The synthetic polymers widely used in petroleum-based plastics include polyethylene (PE), polypropylene (PP), polyvinylchloride (PVC), polyurethane (PUR), polystyrene (PS), polyamide (PA) and polyethylene terephthalate (PET) being the ones used mostly. Polymers with heteroatomic backbone such as PET and PUR are easier to degrade than the straight carbon-carbon backbone polymers such as PE, PP, PS and PVC.

scholarly journals Removal of Heavy Metals from Chithrapuzha River Water by Iron Oxide Nanoparticles Prepared Via Green Synthesis Methods

2020 ◽  
Vol 36 (6) ◽  
pp. 1154-1160
Author(s):  
G. DEEPA ◽  
M. JEYARAJ ◽  
P. N. Magudeswaran
Keyword(s):  
Heavy Metals ◽  
Green Synthesis ◽  
River Water ◽  
Human Life ◽  
Aloe Vera ◽  
Cost Effective ◽  
Water Bodies ◽  
Synthesis Methods ◽  
Healthy Human ◽  
Aquatic Life

On account of industrialization and increasing population, the water bodies get polluted by means of degradable and non-degradable substances. In 21st century, it is necessary to maintain a healthy environment especially water bodies for the survival of not the aquatic animals but also for healthy human life. Recent advances suggest that the issues related to water quality could be resolved by using nanoparticles and nano-filtration membrane methods from the development of nanotechnology. In this research, attempt to remove heavy metals from Chithrapuzha River water at Cochin bar mouth (S1) and Fact barge jetty (S2) using Fe2O3 prepared via green synthesis using Egg albumin and Aloe vera. Our results provoke that, the synthesis of Fe2O3 nanoparticle is cost-effective and eco-friendly and also good in nano-regime. Results of filtration studies showed that Fe2O3 nanoparticles remove heavy metals from Chithrapuzha River water and also increases the DO content which helps the survival of aquatic life.

scholarly journals Metal Oxide Nanoparticles and their Nanocomposite-based Materials as Photocatalysts in the Degradation of Dyes

2021 ◽  
Vol 12 (5) ◽  
pp. 6557-6579
Keyword(s):  
Metal Oxide ◽  
Anthropogenic Activities ◽  
Metal Oxide Nanoparticles ◽  
Chemical Properties ◽  
Cost Effective ◽  
Oxide Nanoparticles ◽  
Synthetic Dyes ◽  
Characterization Methods ◽  
Degradation Of Dyes ◽  
Physical And Chemical

The introduction of inorganic and organic pollutants into water bodies has become a serious issue globally. The waste streams released from the textile, plastic, leather, paper, pharmaceutical, and food industries introduce different natural and synthetic dyes into the aquatic system. Nanomaterials play a significant role in the photocatalytic degradation of dyes present in wastewater. Inorganic metal oxide nanoparticles have many improved physical and chemical properties and attracted much attention in photocatalytic activities. Dyes have been released in our aquatic bodies due to many anthropogenic activities and caused life-threatening problems. Various conventional methods were reported to remove dyes from water and wastewater; the photocatalytic method is one of the efficient and cost-effective. The present review article includes detailed information on photocatalysis, the potential of metal oxide and their composite materials as photocatalysts in the degradation of toxic dyes, and some common synthetic and characterization methods used for metal oxide-based nanoparticles.

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