Commercial Grade Research Articles

Оптимизация двойных каскадов алгоритмом пчелиной колонии для очистки регенерированного гексафторида урана от изотопов232, 234, 236U

We propose a double cascade scheme for reducing the concentration of232, 234, 236U isotopes in regenerated uranium hexafluoride. In the product of the first ordinary cascade the greatest decrease in the236U /235U mass ratio with enrichment in235U to a concentration of less than 20% is provided. To ensure the required concentrations, a special mode of operation of the stages. In the second ordinary cascade, which is fed by the product of the first, enrichment in isotopes232,234U is performed. The waste flow, purified from232, 234U, is diluted to a concentration of235U less than 5%. A method for calculating the parameters of cascades with stage separation factors corresponding to gas centrifuges is presented. A computational experiment was carried out on its basis. It was shown that the product obtained after dilution with respect to isotopes232, 234U meets the requirements of the ASTM C996-20 specification for the low-enriched commercial grade of uranium hexafluoride. The content of236U in it is several times lower than in the case of direct enrichment of regenerated uranium hexafluoride.

Investigating the single pass baffled solar air heater (SAH) with an organic PCM (OPCM)

The current work shows the results of an experimental assessment into the performance of a baffled solar based air heater (SAH-BP) with the organic phase changing material (OPCM) back-up. The experiments were conducted in two modes of operation during two identical solar days in the month of February 2021 at 11.0168° North, 76.9558° East. They were SAH having baffled absorber without any PCM (SAH-BP), and baffled SAH with OPCM (SAH-BP-OPCM). The baffle plates were attached over the absorber surface in alternative sequential way and OPCM was stored beneath the absorber. The normal commercial grade paraffin was employed as OPCM and the experimentations were carried-out at the constant flow rate of 0.18 kg/s. The results substantiated that the amalgamation of OPCM within the baffled SAH enhanced its performance in terms of energy efficiency. The OPCM improved the energy efficiency of the SAH-BP by 11.25%.

Alternate Thermomechanical Heat Treatment Cycles for the Enhancement in Hardness and Tensile Properties of Commercial Grade AA6061

Numerous research incorporating precipitation hardening and/or strain hardening on Al-Mg-Si alloys has demonstrated improved mechanical properties in the alloys. However, there is a lack of research on how these processes can be combined efficiently to provide better strength and hardness for the alloys. The present study describes the effects of low temperature thermomechanical treatment (LTMT - combination of conventional age hardening and strain/work hardening) carried at two isothermal aging temperatures on the hardness and strength of the aluminium alloy 6061 (AA6061). Further, an innovative LTMT process is also proposed, which aims at further enhancing the mechanical properties of the alloy. The study revealed the increase in degree of deformation improved the strength and hardness of the alloy with reduced aging time. The effect of the degree of deformation, pre-deformation, and alternate deformation and aging cycles on the hardness and strength of the alloy was studied with the help of fracture surface analysis.

Bending test and batting by players for the strength analysis of baseball bats made of Dakekanba tree in Hokkaido

Dakekanba is a broad leaf tree popular in Hokkaido. We cut a few trees out of the Teshio research Forest of Hokkaido University. Commercial grade baseball bats were manufactured from the timber. The quality of the bat was examined by laboratory test and also by hitting balls in play fields. The laboratory tests were done by three-point bending to measure the bending load to have the bat broken. The strength in average was much higher than the manufacturer standard for wooden bats. It was found that the breakage occurred in different way showing different paths of cleavage fracture. Some bats showed typical mode of multiple pieces failure (MPF), which should be avoided because of possible accident in play field. The MPF was also found in the bats broken by player. The origin of MPF was examined.

Mobile Mapping System for Automatic Extraction of Geodetic Coordinates for Traffic Signs Based on Enhanced Point Cloud Reconstruction

Lidar sensors are commonly equipped on a mobile mapping system (MMS) to establish point clouds for HD map creation. However, the point clouds themselves do not contain object attributes. Therefore, human operators have to manually obtain objects’ position to assign attributes for further HD map conversion, inevitably resulting in time-consuming processes and significant labor costs. To solve the above problems, in this paper, we present an MMS equipped with non-survey grade Lidar, commercial grade camera, and entry level GNSS/INS, which incorporates ground control points (GCPs) with a Normal Distribution Transform Simultaneously Localization and Mapping (NDT SLAM) refinement and fluctuation adjustment to secure both absolute position accuracy and relative position accuracy of the reconstructed point cloud. Meanwhile, a deep neural network for image detection is employed to obtain the bounding box of traffic signs from each image frame. By applying the translation and rotation transformation between Lidar points and camera pixels, intersection of the detected object in the image and Lidar scan points can be found. By accumulating extracted Lidar points of the traffic sign in several detection frames, we can then obtain an accurate 3D geodetic coordinate of the traffic signs. Experimental results show that point clouds can be reconstructed with an average 3D RMSE of only 8.6cm, and center geodetic coordinates of traffic signs can be further extracted in sub-meter accuracy to significantly reduce labor work in HD map creation.

Experimental study on effect of nano Al2O3 in physiochemical and tribological properties of vegetable oil sourced biolubricant blends

In this study, nine different vegetable oil-based blends were prepared from POME, NOME and TOME by blending with SAE20W40 commercial grade engine oil and 1%, 2% Al2O3 nano particles in weight percentage. The physiochemical properties viz. density, viscosity, viscosity index and flash point were investigated and tribological properties were investigated by four ball lubricant test under ASTM D4172B standard. The results showcased better outcomes with higher percentage (2%) of nanoparticle addition. Especially, the N102 and P202 blends has shown reduction in friction (13.3% and 12.8% respectively) and reduced wear scar diameter (55.1% and 50.5% respectively) when compared with SAE20W40 commercial lubricant.

Evaluation of Nutrient Removal Efficiency with Chitosan: Nutrient Composition and Bacterial Removal in Effluents of Nile Tilapia (Oreochromis niloticus) in the Hatchery

Effluents from aquaculture systems contain large volumes of chemical substances and microbial load such as polychlorinated biphenyls and antibiotics that are often used to control infection and pathogenic bacteria originating from feed or water. These substances, if discharged, create pollution in the aquatic environment. Mitigating this problem requires implementing appropriate treatment methods. This study investigated the efficiency of uptake of nutrients in the wastewater and reduction of microbial pollution by chitosan. This product is a linear polysaccharide composed of β-linked D-glucosamine and N-acetyl-D-glucosamine and can be extracted from the shells of shrimps, lobsters, crabs and other crustaceans that are discarded in bulk quantities by seafood restaurants. The performance of laboratory-produced chitosan (S1) which was prepared from shells of Pacific white leg shrimp (Litopenaeus vannamei) was compared with that of the commercial grade chitosan (S2). While the latter was more effective in nitrogen and phosphorus removal and reduction of total faecal coliform, the two products were comparable in the uptake of minerals from the effluents from a tilapia culture system. The results showed that S1 and S2 adsorbed the nutrients from aquaculture effluents, especially ammonia (NH4 + ), nitrite (NO2 - ), nitrate (NO3 - ) and phosphate (PO4 3-). However, differences were evident in terms of the efficiency of their removal and duration of treatment required for the purpose. In this respect, S2 performed better. Moreover, the anti-bacterial activity of S2 was higher than that of S1, and this appeared to be linked to differences in surface features of the two products. The chitosan extracted from shrimp waste and processed locally provides a low-cost solution to the environmental problems caused by aquaculture effluents.

Comparing the mechanical properties of additively manufactured post-consumer polypropylene to injection molded specimens

Single-use plastic applications have resulted in a staggering amount of plastic waste. The total amount of plastic waste was estimated at 80 million tons in 2015, showing an increasing trend. A significant proportion of the total plastic waste is polypropylene (PP). PP offers good mechanical and chemical properties and can be manufactured and molded in a cost- and energy-efficient manner. This amount of plastic waste is forcing society to develop sustainable recycling strategies. For this reason, commercially available PP feedstocks made from post-consumer waste are available for manufacturing. These materials are primarily designed for injection molding or extrusion processes. Additive manufacturing, and in particular material extrusion-based additive manufacturing (ME-AM), has gained significant momentum over the past decade and is already widely used not only for prototyping but also for series production. PP is a material that is typically challenging to process by ME-AM due to its high crystallinity, high shrinkage, and poor adhesion properties. Therefore, this work investigates the use and applicability of PP recyclates in ME-AM. For this purpose, filaments were produced from a commercial grade PP recyclate and tensile specimens were printed with different printing parameters. The mechanical properties were compared to those of injection molded parts and a good relative performance of 64% to 81% was obtained. Although PP seems to be difficult to process with ME-AM, with an optimized print setup and suitable processing parameters, complex parts could be produced.

Effect of B4C particle reinforcement on tensile properties of Al7075/B4C composites

The tensile properties of the composite materials are of most interest in the application of composite materials in specific environment. The production of composite material plays an important part in deciding the mechanical properties of the composite material. The process parameters selected during the manufacturing of composite material decides the tensile properties of the material. This work is oriented towards developing a new composite material with Aluminium 7075 as the matrix material and reinforcing it with boron carbide as the reinforcing material. The reinforcement substantial is varied in weight percentage and the tensile strength is studied at different compositions for better results. High purity Al7075 is reinforced with 5%, 10% and 15% weight with commercial grade boron carbide. The results demonstrate that the B4C particulates are dispersed in Al7075 matrix phase. With increasing reinforcement weight fraction, tensile strength decreases initially and increases. From ANOVA it has been found that mixing time and B4C weight percentage have more influence on tensile strength. Maximum tensile strength obtained at mixing time of 9 min, B4C weight percent of 15% and with reinforcement particle size of 9 mm.

Spot Lap Joining of Titanium G2 to Nylon 6 by Nylon Extrusion via Friction Forming Technique

To join sheets of commercial pure titanium grade 2 and nylon 6 polymer, friction lap spot welding (FLSW) was proposed. The titanium sheets were drilled to create a 3.5mm diameter hole, which was then threaded with M4. In this work, the effects of the process parameters on joint quality was investigated. The tool's rotating speed was 710, 900, 1120 RPM, the tool's plunging rate was 0.23, 0.75, 1.3mm/sec, and the tool's diameter was 8,10, and 12 mm. All of the specimens were successfully joined, according to the results. The specimens were fully dislocated from the titanium pre-hole after shearing the polymer at the lap joint region. The Ti-nylon 6 joints had shear forces ranging from 597 to 864N. The axial load measured during the joining operation is found to be 199 kg. The joint shear force was most affected by the rotating speed. The two metals were connected by a mechanical interlock at a micron-wide interface line, according to the microstructure analysis.

EXTRACTION AND OPTIMIZATION OF PECTIN FROM COFFEE ROBUSTA PULP AND ITS APPLICATION IN THE FOOD PRODUCT

Coffee is one of the paramount agricultural commodities and the most consumed beverages in the world. A serious problem with the coffee industry now-a-days is huge amount of coffee pulp gets wasted once the coffee beans were separated from its cherries. It is found essentially rich with carbohydrates, proteins, minerals, fat and contains a sufficient level of minor compounds such as pectin, caffeine, tannins, polyphenols. Pectin was extracted by two different methods such as acid hydrolysis and enzymatic extraction at different pH and temperature. Pectin was evaluated for its proximate analysis and physio-chemical analysis such as ash content, moisture content, pectin yield, methoxyl content, equivalent weight, anhydrouronic acid content, degree of esterification, gel forming ability, viscosity & galacturonic acid content. The project was carried out with extraction and optimization of pectin and to incorporate in to the food product. The pectin act as thickening agent and gelling agent and it is incorporated with jam to study its characteristics with commercial food grade.

Behavior of structural lightweight concrete produced with expanded clay aggregate and after exposure to high temperatures

The residual compressive strength of eight lightweight concrete mixtures containing three commercial grading (Liapor HD 5 N, Liapor HD 7 N, and Liapor 8F) of coarse lightweight aggregate (LWA) were determined after to expose at high temperatures. Eight mixes were produced, two by normal weight aggregate and the rest by different types of LWA. The produced concrete was analyzed after high temperature exposure and the effect of using LWA, the type of LWA, and compaction method was studied. To do so, visual inspection, residual compressive strength, crack pattern, spalling, and thermoanalytical analysis were conducted. Generally, it could be concluded that concrete formulations with LWA behave more advantageous up to 500 °C, compared to those with quartz gravel aggregates. Moreover, this study found that an ideal type of LWA to produce structural concrete was Liapor HD 5 N, which was used for producing the mixes L1 and L3.

Direct liquefaction of discarded printer cartridge plastics and its Kinetic Modelling

Electronic waste is growing at an alarming rate in the modern world. Disposal of the plastic materials from discarded electronic items is a major environmental concern and thermochemical recycling has gained lots of attention to effectively convert them into valuable products. In this paper, direct liquefaction of discarded printer cartridge plastic (DPCP) was conducted without using commercial solvent and catalyst and the experiments were carried out under nitrogen atmosphere replacing costly hydrogen. The effect of temperature and residence time on DPCP liquefaction has been assessed. Oil yield increased significantly with temperature and the maximum oil yield of 48.66 wt% was achieved at 400 °C in 15 min. Reaction kinetics of DPCP liquefaction were studied by developing kinetic model with proposed reaction mechanism and the kinetic parameters were evaluated. GC–MS analysis of the oil confirmed the presence of compounds having a carbon chain length in the range of C8- C31, approachable to the carbon chain length of C8- C25 in the diesel fuel. Higher H/C ratio (>1) and comparable physical properties of DPCP liquefied oil with other transportation liquid fuels signify its possible blending with commercial grade fuels after downstream upgrading processes.

Optimization of machining conditions with D type cutting tools using Taguchi technique

In the present study a commercial grade D2, D3 and HSS steel tool materials have been forged and heat treated to induce better hardness. The microstructures of the forged and heat treated tools were seen using metallurgical optical microscopy. The hardness of the cutting tools was recorded with the OMNITECH micro Vickers hardness tester. The D2 tool with 20% forged & heat treated, D3 tool with 20% forged & heat treated and HSS tool exhibited the VHN 629, 610 and 846 respectively. The machining of brass, aluminum and aluminum metal matrix composites were observed with respect to chip generation and materials surface roughness. The machining was carried out at different conditions of work piece rotational speed (300, 540 & 720 m/min), cutting tool feed rate (0.1 & 0.15 mm/rev) and depth of cut (0.3, 0.5 &1 mm). As Taguchi technique helps in simplifying experimental design, data analysis, and prediction of optimum results, it has been employed for the optimization of machining parameters. It is noticed that lower cutting speed resulted discontinuous and segmented chips and larger surface roughness. The larger cutting speeds resulted semi continuous chips with saw toothed tip and comparatively good surface roughness.

Experimental testing of air filter efficiency against the SARS-CoV-2 virus: The role of droplet and airborne transmission

Verifying the capacity of different types of air filters to stop the propagation of the SARS-CoV-2 virus has become a strategic element to contain viral spreading in enclosed spaces. This paper shows the results of experimental tests about the capacity of different commercial filter grades to stop SARS-CoV-2 propagation using inactivated virions. In the first test, the obtained results showed that the F8 filter blocks SARS-CoV-2 propagation if it encounters a flow devoid of liquid phase, i.e., a biphasic flow that can wet the filtering material. On the contrary, as shown in the second test, the SARS-CoV-2 virus propagates through the F8 filter if the droplet content in the air flow is enough to wet it. In these operational conditions, i.e., when the filter is wet by a flow with a high droplet content, the absolute H14 filter was also shown to fail to stop the transmission of the SARS-CoV-2 virus. Lastly, in the third test, the viral load was shown to be stopped when the pathway of the infected droplet is blocked.

Investigation on Utilization of Sodium Silicate Synthesized from Agricultural Waste as a Dispersant in Clay-Based Slip for Ceramic Production

Thailand is the world’s largest rice exporter, tend to continuous increasing the agricultural waste. Burning, to eliminate an agricultural waste, pollutes the air with CO and CO2 emissions which is considered by many in the science community to be a cause of global warming. However, the calcined agricultural waste with the optimum temperature, results in a rich source of active-SiO2. Active-SiO2 was reacted with sodium hydroxide (NaOH) to form sodium silicate (Na2SiO3), called as waterglass or soluble glass. Therefore, sodium silicate is often used as a deflocculant in clay-based ceramic slip production to reduce viscosity instead of adding large amounts of water. In this work, rice straw and rice husk are an agricultural waste and used as a starting material. Before used, the reaction temperature of agricultural waste is checked by using DTA-TGA technique. The waste was first calcined at 600 °C for 2 h in air to remove organic matter and produce high purity of active-SiO2. This was then added to NaOH as the starting material for Na2SiO3 synthesis. Then used synthesized Na2SiO3 as a dispersant in clay-based ceramic slip. The phase, viscosity, porosity, and particle arrangement were tested and compared with commercial grade of Na2SiO3. Sodium silicate from agricultural waste exhibited high-performance deflocculant behavior, with reduced viscosity and water demand of clay minerals. Card pack particle arrangement resulted in increased density and low porosity, and directly endowed the ceramic products with high strength. For reducing waste and environmental impact, the result suggested that sodium silicate produced from agricultural waste, can be utilized as a promising and alternative natural deflocculant to clay-based ceramic slip in the ceramic manufacturing process to decrease production costs.

Preparation and properties of bio-lubricants of neopentylglycol esters from various acids

In this work, two different neopentyl glycol (NPG) esters have been synthesized from NPG with 10- undecylenic acid (UDA) and calophyllum fatty acid (CFA) by the esterification process by using para toluene sulfonic acid as a catalyst. The esterification reaction progress has been determined by collecting measured water by using the Dean Stack apparatus. The prepared ester structures have been characterized by NMR, IR and the general physico-chemical behaviors such as density, viscosity, flash point, pour point and copper strip corrosion were determined. Moreover, these prepared ester properties have been compared to commercial ISO VG grade lubes.

Experimental performance of a solar air heater using straight and spiral absorber tubes with thermal energy storage

A flat plate solar air collector is a simple energy conversion system with relatively poor performance due to low heat transfer between air and absorber. Passive heat transfer enhancement methods increase the absorber-side contact area and the localized air turbulence. This research article introduces a dual-purpose copper tube as an extended absorber surface as well as heat storage. The absorber designs are spiral coiled and straight tubes with uniform spacing, filled with glycerol and commercial grade paraffin. Thermal and exergy efficiencies of modified solar air heater configurations are compared with conventional collector with a plain absorber without energy storage. The experimental results show that the double-pass solar collector with a spiral tube with paraffin wax has higher thermal performance than the straight tube and conventional collectors. The spiral coil's thermal and exergy efficiencies with paraffin wax are 29.86% and 1.11%, respectively, at an airflow rate of 0.0076 kg/s with a maximum attained air temperature of 59 °C. The air temperature is maintained for a short time in the heat storage-based absorber even after sunset. Thus, the integration of thermal storage into the solar collector stores the heat for off-sunshine hours and enhances the absorber's energy storage capacity and uniform temperature. The modified absorber surface with heat storage results in better performance without auxiliary power. Further, the enviro-economic study ensures a lower payback period for PCM-integrated spiral tube collectors of about 2.4 years. Such simple and economic absorber designs are beneficial to various solar drying and space heating applications.

Comparative Physiochemical Analysis of Kachi Ghani, Solvent Oil and refined Oil Extracted from Brassica nigra

Brassica nigra or black mustard is traditionally used in various states of India from the ages. It is being commercially used in the form of kachi ghani, solvent oil (non-edible), and refined oil. Due to the antioxidant and antibacterial properties of kachi ghani mustard oil, it is considered to be of better quality. On the other hand, literatures also state that refined oil is better due to the purification processes. There is ambiguity regarding quality aspects of these three oil fractions. Therefore, the present study was planned for the comparative analysis the quality and physiochemical characterization of kachi ghani, solvent and refined oil. Commercially free fatty acids value, acid value, color, presence of argemone, pungency of oil and content of various monounsaturated fatty acids, saturated fatty acids and polyunsaturated fatty acids is determined to check quality of commercial grade edible oils. In consequence, it was observed that kachi ghani consists of less free fatty acids (0.37±0.02%), less acid value (0.74±0.04mg/g) and high pungency (0.279%) as compared to solvent and refined oil. Kachi ghani embrace more natural color (32.0 units) in comparison to solvent oil which was way darker and refined oil which was very light. The percentage of saturated fatty acids, monounsaturated fatty acids and polyunsaturated fatty acids was spotted to be 6.44%, 64.360% and 28.64% respectively in kachi ghani oil. The study shows that saturated fatty acids such as palmitic C-16, stearic C-18, behanic C-22 and lignoceric C-24 were present in kachi ghani. In solvent oil, palmitic C-16, stearic C-18, behanic C-22, and lignoceric C-24 were found whereas only palmitic acid was present in refined oil. High content of monounsaturated fatty acids were found in oil. Eicosenoic C-20:1, Oleic C-18:1, Eurcic C 22:1 and Nervonic C-24:1 unsaturated fatty acid was found in all the three fractions of oil.

Representation of gas metal arc pulsed welding process behavior on bead geometry: a study of leading variables

Gas metal arc welding is one of the most influential processes in the production and repair of structures and equipment; therefore, the need to improve the productivity and quality of welded joints has led to the development of techniques for good control of welding parameters. Also, the development of semi-automatic welding processes led to the control of one of the variables such as pulsed current; this technique is characterized by a lower heat input and lower energy expenditure, which directly influences the structural quality of the welded joint and the geometry of the weld bead. This work focused on evaluating the effects of various welding operating parameters using the central composite design tool based on the response surface methodology; next, the experimental development employed an inverter type power source for weld depositions, a commercial grade Stargold clean 96% Ar and 4% CO2 shielding gas at the rate of 15 L/min stationary arc, a 1.2 mm metal cored wire for welding deposit and a carbon steel base plate with a thickness of 6 mm. During the welding process, the torch was kept at a 90° inclination and a 16 mm stroke. To examine the adequacy of the empirical models and the significance of the regression coefficients, the variance analysis was employed. Consequently, the graphs were obtained through the determination of the model; from the statistical results obtained, it was shown that the above models were adequate to predict the weld width, bead height, and penetration within the range of variables studied. Furthermore, it was observed that the wire feed rate it has a very marked effect on weld bead geometry, followed by frequency pulse and peak current; finally, the effectiveness of employing these methodologies for the management of variables attributing to the execution of welding tasks with higher accuracy was demonstrated.