The issue of corrosion is a major problem on equipment failure and damage in industrial that would affect the safety and efficiency of the equipment. Especially, materials used in marine environments ...have to withstand corrosion and need more hardness to withstand corrosion. Nickel–aluminum bronze (NAB) alloys show good corrosion resistance under marine conditions. Therefore material requirements to withstand such a high corrosive environment are most important. Along with these, cost effectiveness also considered in the usage of material. Many papers gives the corrosion resistance of behavior of NAB alloys in sea water or 3.5M NaCl solution in detail manner. But the alternate material to NAB is not studied as copper is the material shows very high corrosion resistance in sea water. In order to enhance the properties of NAB alloy, chromium is added additionally and excluding iron, manganese, bronze, etc of the NAB alloy. This paper will be focusing on the influence of chromium addition to the aluminum nickel alloy in the corrosion resistance properties and hardness. Chromium is added in 4%, 8% and 12% through powder metallurgy route. The specimen prepared for the corrosion testing by sintering and hot – extrusion. The electro-chemical corrosion test was carried out in Potentiostat in order to find out the corrosion properties of the alloys. The corrosion properties were increased than the available alloy composition of ASTM B505M – 14. Further, the micro-vicker’s is done which shows that the micro-hardness also has got increased due to the addition of chromium. The main aim of the paper is to find an alternate material which withstands high corrosive environment especially in salt water and also high strength.
The Gas Tungsten Arc Welding process weld for the 4 mm thickness of the ASTM A36 steel plate with varied heat input parameters of 0.608 kJ/mm, 0.900 kJ/mm and 1.466 kJ/mm, respectively. The effect of ...different heat inputs on microstructure, corrosion, and mechanical characteristics of developed weld joints are examined by three zones: heat-affected zone, welded zone, and base metal zone. The optical microscopic results of weld joints illustrate that fine grain structure leads to enhance welding strength. It is revealed that the increased heat input parameter on the weld joint shows a decreased tensile strength and hardness of the weld joint. The corrosion resistance of the weld joint is evaluated by Potentio-dynamic polarization. It facilitates that the corrosion rate of the weld joint is decreased with increasing heat input, which results indicate the best and worst corrosion micrograph of the polygonal ferrite and ferrite plus polygonal ferrite. However, the weld joint prepared with 0.900 kJ/mm heat input found maximum corrosion resistance.
Jet fuel production is a key element in the aviation industry’s strategy to reduce operating costs and environmental impacts. Alternatives are required, and bioturbosine obtained from biomass can ...replace significant amounts of jet fuel. In this investigation, the properties of the production of bioturbosine from coconut oil and mixtures of B5, B10, B20, B1OO, bottom, and jet fuel were measured according to the ASTM standards. A transesterification reaction between coconut oil and methanol was carried out using ultrasound, resulting in 99.93% conversion of triglycerides into bioturbosine at room temperature for 10 min, with a 6:1 molar ratio of methanol and oil. The catalyst concentration was 1.0 g/100 g of oil, and purification was carried out without water using an ion-exchange resin to remove impurities. The results obtained for density and viscosity were within the regulations. The temperature of the clogging point for a cold filter in the mixtures was up to −30 °C. The average caloric values of mixtures B5, B10, and B20 were 45,042, 44,546, and 43,611 MJ/Kg, respectively. In a copper corrosion test, the result for all samples was class 1A. It is expected that the results of this research may influence the use of bioturbosine in the aviation industry.
Ultrafast gas chromatography (UFGC) along with supervised and unsupervised chemometric methods were utilized for evaluation of biodiesel-diesel blended fuels. A variety of biodiesel feedstocks ...(soybean, tallow, canola, safflower, sunflower, camelina, flaxseed, etc.) and concentrations (1–20%) were evaluated. The method, which uses a short nonpolar column, falls within ASTM D7798 requirements for diesel and extends the method to include biodiesel-diesel blended fuels. Using Principal Components Analysis (PCA), samples clustered based on concentration and diesel type, and differences in plant and animal feedstocks were apparent. Biodiesel concentration was accurately assessed using Partial Least Squares (PLS) on a training set for B0–B20, while predictions were made with some success on a set of commercial and lab unknowns. k Nearest Neighbors (kNN) was used to describe and predict concentration, plant versus animal feedstock, and to identify biodiesel blends. The combination of chemometric methods alongside UFGC proves an effective and fast technique for the analysis of biodiesel source and composition in biodiesel-diesel blended fuels.
Coal rheology is a critical parameter for determining the coking and caking ability of metallurgical coals for cokemaking. The effect of rank, hardness differences due to rank, and particle size on ...the resultant fluidity and dilatation results were demonstrated for various rank Applachian coals in previous studies. Particles less than USA Standard screen size No. 140 had poorer rheology responses compared to other size fractions. For the third phase of this study, the effect of particle size and rank of Western Canadian coals were also evaluated. All samples and rheology parameters were determined prepared using the standard ASTM methods. In addition, rheology was also measured on sized subsets to determine the effect of particle size and rank on the overall rheology results but from a different geological era compared to Applachian coals. Particle size limits for the Gieseler and Dilatometer tests are suggested. The importance of using temperature range is also emphasized.
The application of additive biomanufacturing represents one of the most rapidly advancing areas of biomedical science, in which engineers, scientists, and clinicians are contributing to the future of ...health care. The combined efforts of a large number of groups around the globe have developed a strong research thrust that has resulted in a large number of publications. Reviewing this body of literature, there is an increasing trend of research groups inventing their own definitions and terminology. This has made it difficult to find and compare the results. Therefore, to move the field constructively forward, it is a conditio sine qua non to clarify various terminologies and standards. Based on this background, this article advocates tightening the terminology and has the objective of penning out definitions that will ultimately allow the development of official industry standard terms, such as American Society for Testing and Materials and or International Organization for Standardization for technologies developed for Tissue Engineering and Regenerative Medicine.
•Introduction of new non-edible oil source for bioenergy industry.•Nano-particles MgO used as a heterogeneous catalyst.•Maximum conversion yield at optimum level achieved 93.1%.•Fuel properties were ...matched and found similar to ASTM standards.
Synthesis and characterization of methyl esters from non-edible oil sources provide a distinctive and sustainable approach towards sustainable energy and the cleaner environment, in general. This study aims the synthesis of methyl esters from non-edible plant species yellow oleander seeds oil. The transesterification process was carried for the synthesis of methyl esters, using heterogeneous nano-catalyst magnesium oxide (MgO). A well known co-precipitation method was used for the synthesis of MgO nano-catalyst. The application of MgO nano-catalyst showed the maximum conversion (93.1%) of triacylglycerols to methyl esters. Different parameters affecting the conversion percentage; alcohol to oil molar ratio, temperature and catalyst concentrations were checked and optimized, accordingly. The optimum conditions for the maximum conversion noted; 1:5 oil to methanol molar ratio at 90 °C, using 0.2% (w/w) MgO nano-catalyst. The various analytical techniques; XRD, SEM-EDX and TEM-EDS spectroscopes were used to check out the nano-particle morphology and crystalline size, accordingly while, the FTIR, GC–MS & NMR were used to quantify and determine the structural measurements of synthesized methyl esters. The fuel properties of oleander methyl esters papered sample were checked, compared and found within accordance to the ASTM standards.
Alkali–silica reaction (ASR) is one of the major durability issues that affect the material degradation and structural performance, compromising the service life of concrete structures. Therefore, ...this study was planned to investigate the potential of ASR for locally available unexplored and vastly used aggregates, as per ASTM C1260. Aggregates from five different sources (Shalozan, Abbotabad, Orakzai, Swabi and Sada) were procured from their respective crusher sites. Mineralogical components of these aggregates were studied using the petrographic analysis. Cube, prism and mortar bar specimens were cast using mixture design in accordance with ASTM C1260 and placed in sodium hydroxide solution at 80 °C for 90 days. Identical specimens were also cured in water for the purpose of comparison. It was observed that mortar bar expansion of Orakzai aggregate was higher among the other tested aggregates and greater than 0.20% at 28 days, indicating the reactive nature according to ASTM C1260. Petrographic analysis also revealed the presence of reactive silica (quartzite) in the tested Orakzai source. It was observed that the compressive and flexural strengths of specimens exposed to ASR conducive environment was lower than the identical specimens placed in water. For instance, an approximately 9% decrease in compressive strength was observed for Orakzai aggregates exposed to ASR environment at 90 days compared to similar specimens placed in water curing. Moreover, microstructural analysis showed the development of micro-cracks for specimens incorporating Orakzai source aggregates. This study assists the construction stakeholders for the potential of unexplored local aggregates with regard to ASR before its utilization in mega construction projects.
•88% of 222Rn contamination is removed with methods proposed in EN 15440:2017 and US D6866 – 11.•Plausible biogenic content biases is expected to be about +0.2% and can reach up to +2%.•222Rn removal ...method that reduces the contamination by a factor of 103 is proposed.
In recent years standardized methods for determining biobased content using 14C liquid scintillation spectrometry (LSC) have been developed. However, 222Rn contamination can artificially increase the apparent 14C content and hence the biobased content. In EN 16640:2017 and ASTM D6866–11 methods, which describe the calculation of biobased content using 14C LSC measurements, it is stated that 222Rn can be removed by pumping benzene at dry ice temperatures.
In this work we examine this claim by investigating the removal efficiency of 222Rn using the proposed process. First, 222Rn-rich air was injected into benzene, which was then pumped while frozen at dry ice temperatures. Finally, the remaining 222Rn contamination was measured using an ultra-low level liquid scintillation system with a 214Bi/214Po pair counting technique.
The results indicated that after a single freeze-pump cycle at dry ice temperatures 12% of 222Rn contamination remained. Taking 222Rn contamination from our earlier works, we estimated that the plausible average error was 0.18% for a typical sample and could reach up to 2% of the biogenic content for the most highly-contaminated natural samples measured in our laboratory. These experiments were repeated several times at different temperatures but the results were not significantly affected by the temperature.
Finally, we propose a 222Rn removal method that reduces the contamination by a factor of 103 that can be performed on vacuum lines for benzene production that are used in most liquid scintillation radiocarbon laboratories.
The conventional way to present Integral Method calibration data for hole-drilling residual stress measurements is in the form of a large triangular table of numbers. In the common case where 20 ...drilling steps are used for the hole-drilling measurement, 231 numerical coefficients are needed. While such tables are effective, their bulk inhibits their use for other than the most common experimental arrangements; the convenience and usefulness of the hole-drilling method would be much extended if the bulk of the calibration data could be reduced. Here, a two-variable polynomial formulation is proposed to represent the hole-drilling calibration data. It comprises 15 numerical coefficients and provides calibration data with average accuracy within 1%, with occasional outliers reaching around 2%. The compactness of the calibration stimulated exploration of hole-drilling response beyond the conventional “thick” specimen case, also to include finite thickness specimens down to very thin (through-hole) geometries. Tables of calibration data are provided here for ASTM E837 Type A, B and C strain gauge rosettes, for various hole diameters, for conventional “thick” specimens, and for finite thickness specimens down to the through-hole case.
PDF
