Linear-nonlinear stiffness responses of carbon fiber-reinforced polymer composite materials and structures: a numerical study

The stiffness response or load-deformation/displacement behavior is the most important mechanical behavior that frequently being utilized for validation of the mathematical-physical models representing the mechanical behavior of solid objects in numerical method, compared to actual experimental data. This numerical study aims to investigate the linear-nonlinear stiffness behavior of carbon fiber-reinforced polymer (CFRP) composites at material and structural levels, and its dependency to the sets of individual/group elastic and damage model parameters. In this regard, a validated constitutive damage model, elastic-damage properties as reference data, and simulation process, that account for elastic, yielding, and damage evolution, are considered in the finite element model development process. The linear-nonlinear stiffness responses of four cases are examined, including a unidirectional CFRP composite laminate (material level) under tensile load, and also three multidirectional composite structures under flexural loads. The result indicated a direct dependency of the stiffness response at the material level to the elastic properties. However, the stiffness behavior of the composite structures depends both on the structural configuration, geometry, lay-ups as well as the mechanical properties of the CFRP composite. The value of maximum reaction force and displacement of the composite structures, as well as the nonlinear response of the structures are highly dependent not only to the mechanical properties, but also to the geometry and the configuration of the structures

Refinement of fertilizer recommendation based on Soil Test Crop Response technology for rice under System of Rice Intensification

A study on Soil Test Crop Response based Integrated Plant Nutrition System (STCR - IPNS) were conducted adopting an Inductive cum Targeted yield model in non-calcareous sandy loam soils of Lithic Haplusteptat Regional Research Station, Tamil Nadu Agricultural University, Paiyur, Tamil Nadu during Kharif 2013 in orderto develop fertilizer prescriptions equation (FPEs) through IPNS for the desired yield targets of rice under SRI technique. A ready reckoner of fertilizer doses at varying soil test value, for attaining 6 to 9 t ha-1 target grain yield of rice has been worked out. Using these equations a validation trial was conducted on Kharif 2014 at this station. The grain yield of rice ranged from 2.54 t ha-1 in absolute control to 8.65 t ha-1 in STCR-IPNS-9 t ha-1. The STCR-IPNS @ 8 t ha-1 was effective and economical as compare with any other treatments. The deviation recorded in the achievement of targets aimed was within the range of ± 10 per cent (90 – 110 %) proving the validity of the FPEs. The STCR treatments recorded relatively higher response ratio (RR) and benefit-cost ratio (BCR) over blanket and farmer's practice and STCR-IPNS treatments recorded relatively higher RR and BCR over STCR-NPK alone treatments. Post-harvest soil tests for NPK revealed that there was maintenance of soil fertility. The STCR-IPNS @ 8 t ha-1 was effective and economical as compare with any other treatments. Thus, the Inductive cum Targeted yield model used to develop fertilizer prescription equations provides a strong basis for soil fertility maintenance consistent with high productivity and efficient nutrient management for sustainable and enduring Agriculture

Domestic wastewater treatment using multi-layer constructed wetlands: an overview

Domestic wastewater is generated from residential, institutional, commercial, and industrial establishments is disposed of via drainage and sewers. Usually, the wastewater is not treated from the primary sewage treatment and gets discharged to drainage without initial treatment. Thus, it is necessary to create an environmentally-friendly method to reduce any pollution issues. This chapter provides insights into overview from previous studies about characteristics of domestic wastewater, results of the treatments using the multi-layer constructed wetlands, type of plants for vegetation wetlands, and parameters needed for the optimisation the multi-layer constructed wetlands. As the low-cost and affordable technology systems, the multi-layer constructed wetlands are the potential alternative to achieve the treatment efficiency

Interaction of Z-pins with Multiple Mode II Delaminations in Composite Laminates

The application of Z-pinning is a subject of great interest in the field of through-thickness reinforcement (TTR) of composite laminates. To date, the majority of Z-pin characterisation work has been conducted on fracture coupons containing a single embedded delamination, which is often not representative of real failure of reinforced composite structures in service. In this investigation a test procedure to produce two independent Mode II delaminations was developed to analyse their interaction with a region of Z-pin reinforcement. Initially numerical models were used to optimise the chosen configuration. Experimental results show in detail the response of Z-pins to two independent delaminations. These results highlight the ability of the Z-pins to effectively arrest mode II delaminations at multiple levels through the sample thickness. Additionally they provide a much needed data set for validation and verification of Z-pin numerical modelling tools

Evaluation the Antimicrobial Activity of Artemisia and Portulaca Plant Extracts in Beef Burger

Medicinal plants contain substances can alternate the traditional chemical preservatives which used for preserving meat products that have negative effects on consumer health. Several biological activities have been reported for Artemisia and Portulaca as antimicrobial agents, so the current study focused on using Artemisia and Portulaca extracts as antimicrobial agents in beef burger. Phytochemical of Artemisia and Portulaca extracts were analyzed, and both extracts contain alkaloids, flavonoids, phenols, trepenoids and saponin. The results show that Artemisia extract was inhibited all tested microorganisms (Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella Typhimurium, Listeria monocytogenes and E.coli O157:H7) while, Portulaca extract affect Staphylococcus aureus only. The Minimum Cidal Concentration (MCC) and Minimum Inhibitory Concentration (MIC) were carried out for testing microorganisms, since Artemisia extract was very effective against Staphylococcus aureus followed by E.coli, Pseudomonas aeruginosa, Salmonella Typhimurium and L. monocytogenes. Artemisia and Portulaca extracts were separately applied in beef burger as antimicrobials at levels 1% and 1.5%. The sensory evaluation of treated beef burger showed no significant differences between control sample and treatments containing Portulaca extract while, the addition of Artmesia extract had a detrimental effect on taste of beef burger since it causes formation of bitter taste

Shariah Screening Methodologies: SAC-SC Vs DJIM Comparative Study and Impact Assessment on Their Performance

Purpose – The purpose of this paper is to compare between two screening methodologies in terms of applied methods and the impact assessment. Other than this the paper measures the performance of screened stocks in terms of risk & return and compare it to the conventional onesDesign/methodology/approach – The methods used are a combination of archival and bibliographic research based on some previously published articles. Also the papers use secondary data from published reports.Findings – The paper identifies the impact assessment of the screening methodologies and how investors will not sacrifice part of their returns in order to achieve their moral and ethical values.Originality/value – Many studies compared the two screening indices in term of methodologies; however this paper investigates and uses a quantitative analysis on the impact and performance of the screening methodologies. Furthermore it compares the stages of screening between Shariah Advisory Council of Securities commission (SAC-SC) and Dow Jones Islamic Market Index (DJIM)Keywords – screening, methodologies, impact assessmentPaper type – comparative case stud

Laboratory bred prawns from Narakkal cultured in salt pan reservoirs at Tuticorin—a success story.

Rapid developments and fast changes are taking place in the field of prawn culture in india and abroad. Domestication of the culturable species of marine prawns, their induced maturation and spawning in captivity and mass production of stockable size of prawn seeds have become a reality in india chiefly due to the researches conducted at the narakkal prawn culture laboratory (npcl) of the central marinefisheries research institute. Establishment of a land-based maturation facility and development ofMass cultures of locally available live feed organisms—diatoms, rotifers and cladocerans—were the major contributory factors in achieving this break-through. As a result of these developments over one million prawn seeds, chiefly belonging to the indian prawn penaeus indicus were produced at the npcl in the eariy half of 1980.the prawn seeds produced at the npcl were byproducts of the experiments conducted there and not products of a concerted production programme. Although most of these seeds were used in the lab to land programme of the institute at the vypeen island and quilon, some were supplied to the prawn culturists at goa and tuticorin and also to the calicut research. Centre of the cmfri for experiments in the polythene lined ponds on the sandy beach of calicut. The main objective of these supplies was to study the problems associated with long distance transport and to evaluate their growth and survival in different ecological conditions