scholarly journals Synthesis of Zinc Fluoroborate by Wet Method and Its Application as a Flame Retardant for Cotton Fabrics

2021 ◽  
Author(s):  
Duygu Yılmaz Aydın ◽  
◽  
Metin Gürü ◽  
Keyword(s):  
High Temperature ◽  
Flame Retardant ◽  
Large Scale ◽  
Maximum Yield ◽  
Cotton Fabrics ◽  
Test Method ◽  
Reactant Ratio ◽  
Selective Electrode ◽  
Durability Test

In this study, zinc fluoroborate was synthesized by wet method using fluoroboric acid and zinc oxide as reactant and its usability as flame retardant for cotton fabrics was investigated. The wet method is economical, green, efficient and applicable for a large-scale. The maximum yield was determined related to the variation of reactant ratio, temperature, reaction period and stirrer rate. The characterization of the product was carried out by means of FTIR, BF4- ion selective electrode and XRD. The maximum yield of 97% was achieved at the reactant mole ratio (nZnO/nHBF4) of 1:3, temperature of 90 °C and reaction period of 90 minutes. The purity of the synthesized product was found as 98 %. Flame retardancy and high temperature resistance effects of zinc fluoroborate on cotton fabrics were investigated by LOI test and high temperature durability test method, respectively. Although LOI value of the untreated original fabric was determined as 16, this value increased above 55 by impregnating of fabric with 50 % zinc fluoroborate solution.

High-Temperature Interlaminar Tension Test Method Development for Ceramic Matrix Composites

2013 ◽  
Author(s):  
Todd Engel
Keyword(s):  
High Temperature ◽  
Method Development ◽  
Standardized Test ◽  
Ceramic Matrix Composite ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Test Method ◽  
Test Technique ◽  
Structural Applications

Ceramic Matrix Composite (CMC) materials are an attractive design option for various high-temperature structural applications. In particular, the use of CMC materials as a replacement for state-of-the-art nickel-based superalloys in hot gas path turbomachinery components offers the potential for significant increases in turbine system efficiencies, due largely to reductions in cooling requirements afforded by the increased temperature capabilities inherent to the ceramic material. However, two-dimensional fabric-laminated CMCs typically exhibit low tensile strengths in the thru-thickness (interlaminar) direction, and interply delamination is a concern for some targeted applications. Currently, standardized test methods only address the characterization of interlaminar tensile strengths at ambient temperatures; this is problematic given that nearly all CMCs are slated for service in high-temperature operating environments. This work addresses the development of a new test technique for the high-temperature measurement of interlaminar tensile properties in CMCs, allowing for the characterization of material properties under conditions more analogous to anticipated service environments in order to yield more robust component designs.

Preparation and characterization of flame-retardant lamellar Mg(OH)2 thin films on citric acid-treated cotton fabrics

2011 ◽  
Vol 43 (5) ◽  
pp. 903-912 ◽  
Author(s):  
Qinghui Mao ◽  
Linping Zhang ◽  
Dehui Huang ◽  
Dan Wang ◽  
Yang Huang ◽  
...  
Keyword(s):  
Thin Films ◽  
Citric Acid ◽  
Flame Retardant ◽  
Cotton Fabrics

scholarly journals Preparation and characterization of flame retardant cotton fabrics

2020 ◽  
Vol 10 (2) ◽  
pp. 5296-5300
Keyword(s):  
Flame Retardant ◽  
Cotton Fabric ◽  
Cotton Fabrics ◽  
Curing Temperature ◽  
Sodium Hypophosphite ◽  
X Ray ◽  
Untreated Cotton ◽  
Prepared Glass ◽  
Ray Patterns

An inorganic flame retardant glass was prepared using the melt methods. The prepared glass was characterized using IR, X-ray. The x-ray patterns and IR charts show that the formation of glass without any crystals. Cotton fabric was finished using different percentage of glass 0.5, 1, 1.5 and 2 % (w/w) in the presence of citric acid as crosslinker and sodium hypophosphite as catalyst. The flame retardancy of finished cotton fabric was performed using Limited Oxygen Index (LOI) technique. The results of measurements show that the value of LOI of untreated cotton fabric equals 19.6, when cotton fabrics treated with different amounts of glass ranging from 0.5 to 2 %, the value of LOI increased to become 23.6 at 0.5% and 24.8 for the higher glass concentration. The effect of curing temperature and time on the properties and the LOI of cotton fabric was studied.

scholarly journals Characterization of self-heating in stored waste

2017 ◽  
Author(s):  
Henry Persson
Keyword(s):  
Large Scale ◽  
Spontaneous Combustion ◽  
Isothermal Calorimetry ◽  
Test Procedure ◽  
Test Method ◽  
Evaluation Methodology ◽  
Small Scale ◽  
Self Heating ◽  
Scale Test

A common cause of fires in large bulk storages is spontaneous combustion. This project aimed at creating a general test procedure and an evaluation methodology to obtain relevant risk parameters for different types of waste with respect to self-heating characteristics and the risk of spontaneous combustion. SLF (Shredder Light Fraction) from shredding of automobiles has been used as a pilot waste. The methodology is aiming at being used by e.g. the waste management sector in order to examine the propensity to self-heating of a specific waste fraction. Based on such characterization, storage could be better planned to avoid fires. The work of the project showed that with a combination of a relatively large scale test method (1 m3), and isothermal calorimetry one can study both how a material behaves regarding self-heating in bulk form and how the various constituent components affect self-heating. This means that these methods can give an indication on the cause of a specific fire, on which components of a given waste contribute to the self-heating, on how a particular mixture behaves in relationships to another, etc. In summary the developed methodology involves: 1) Representative sampling and characterization of the waste including grinding of subsamples for analysis by laboratory methods, 2) Analysis of heat generation from self-heating by isothermal calorimetry, 3) Determination of thermal properties of the waste bulk material by using a small-scale test method (TPS) for the heat capacity and for the effective thermal conductivity, 4) Large scale self-heating tests with the waste in its original fraction to provide information on critical temperatures for varying storage conditions.

Some applications of electron beam microanalysis techniques in VLSI process evaluation

1983 ◽  
Vol 41 ◽  
pp. 160-161
Author(s):  
Simon Thomas
Keyword(s):  
Integrated Circuits ◽  
Process Evaluation ◽  
Large Scale ◽  
Technology Development ◽  
Analytical Techniques ◽  
Successful Implementation ◽  
Analysis Of Failures ◽  
Characterization Of Materials ◽  
Circuits Vlsi

Trends in the technology development of very large scale integrated circuits (VLSI) have been in the direction of higher density of components with smaller dimensions. The scaling down of device dimensions has been not only laterally but also in depth. Such efforts in miniaturization bring with them new developments in materials and processing. Successful implementation of these efforts is, to a large extent, dependent on the proper understanding of the material properties, process technologies and reliability issues, through adequate analytical studies. The analytical instrumentation technology has, fortunately, kept pace with the basic requirements of devices with lateral dimensions in the micron/ submicron range and depths of the order of nonometers. Often, newer analytical techniques have emerged or the more conventional techniques have been adapted to meet the more stringent requirements. As such, a variety of analytical techniques are available today to aid an analyst in the efforts of VLSI process evaluation. Generally such analytical efforts are divided into the characterization of materials, evaluation of processing steps and the analysis of failures.

The Potential of Photoelectrochemical Carbon Sinks

2018 ◽  
Author(s):  
Matthias May ◽  
Kira Rehfeld
Keyword(s):  
Global Warming ◽  
High Temperature ◽  
Greenhouse Gas ◽  
Large Scale ◽  
High Efficiency ◽  
Carbon Sink ◽  
Solar Fuels ◽  
Negative Emissions ◽  
Viable Approach ◽  
Low Sensitivity

Greenhouse gas emissions must be cut to limit global warming to 1.5-2C above preindustrial levels. Yet the rate of decarbonisation is currently too low to achieve this. Policy-relevant scenarios therefore rely on the permanent removal of CO<sub>2</sub> from the atmosphere. However, none of the envisaged technologies has demonstrated scalability to the decarbonization targets for the year 2050. In this analysis, we show that artificial photosynthesis for CO<sub>2</sub> reduction may deliver an efficient large-scale carbon sink. This technology is mainly developed towards solar fuels and its potential for negative emissions has been largely overlooked. With high efficiency and low sensitivity to high temperature and illumination conditions, it could, if developed towards a mature technology, present a viable approach to fill the gap in the negative emissions budget.<br>

The Potential of Photoelectrochemical Carbon Sinks

2018 ◽  
Author(s):  
Matthias May ◽  
Kira Rehfeld
Keyword(s):  
Global Warming ◽  
High Temperature ◽  
Greenhouse Gas ◽  
Large Scale ◽  
High Efficiency ◽  
Carbon Sink ◽  
Solar Fuels ◽  
Negative Emissions ◽  
Viable Approach ◽  
Low Sensitivity

Greenhouse gas emissions must be cut to limit global warming to 1.5-2C above preindustrial levels. Yet the rate of decarbonisation is currently too low to achieve this. Policy-relevant scenarios therefore rely on the permanent removal of CO<sub>2</sub> from the atmosphere. However, none of the envisaged technologies has demonstrated scalability to the decarbonization targets for the year 2050. In this analysis, we show that artificial photosynthesis for CO<sub>2</sub> reduction may deliver an efficient large-scale carbon sink. This technology is mainly developed towards solar fuels and its potential for negative emissions has been largely overlooked. With high efficiency and low sensitivity to high temperature and illumination conditions, it could, if developed towards a mature technology, present a viable approach to fill the gap in the negative emissions budget.<br>

Characterization of seawater reverse osmosis fouled membranes from large scale commercial desalination plant

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Reverse Osmosis ◽  
Large Scale ◽  
Retention Rate ◽  
Local Level ◽  
Microscopic Analysis ◽  
Transmembrane Pressure ◽  
Hydraulic Permeability ◽  
Seawater Reverse Osmosis ◽  
A Chain

The objective of this work is to study the ageing state of a used reverse osmosis (RO) membrane taken in Algeria from the Benisaf Water Company seawater desalination unit. The study consists of an autopsy procedure used to perform a chain of analyses on a membrane sheet. Wear of the membrane is characterized by a degradation of its performance due to a significant increase in hydraulic permeability (25%) and pressure drop as well as a decrease in salt retention (10% to 30%). In most cases the effects of ageing are little or poorly known at the local level and global measurements such as (flux, transmembrane pressure, permeate flow, retention rate, etc.) do not allow characterization. Therefore, a used RO (reverse osmosis) membrane was selected at the site to perform the membrane autopsy tests. These tests make it possible to analyze and identify the cause as well as to understand the links between performance degradation observed at the macroscopic scale and at the scale at which ageing takes place. External and internal visual observations allow seeing the state of degradation. Microscopic analysis of the used membranes surface shows the importance of fouling. In addition, quantification and identification analyses determine a high fouling rate in the used membrane whose foulants is of inorganic and organic nature. Moreover, the analyses proved the presence of a biofilm composed of protein.

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