Sampling of Gas-Phase Intermediate Pyrolytic Species at Various Temperatures and Residence Times during Pyrolysis of Methane, Ethane, and Butane in a High-Temperature Flow Reactor

Air pollution in many major cities is endangering public health and is causing deterioration of the environment. Particulate emissions (PM) contribute to air pollution as they carry toxic polyaromatic hydrocarbons (PAHs) on their surface. Abatement of PM requires continuous strict emission regulation and, in parallel, the development of fuels with reduced formation of PM. Key processes in the formation of PM are the decomposition of hydrocarbon fuels and the synthesis of potential precursors that lead to the formation of benzene rings and thereafter growth to PAHs and eventually PM. Methane, ethane and butane are important components of natural gas and liquefied petroleum gas, and are also widely used in transportation, industrial processes and power generation. This paper reports on a quantitative investigation of the intermediate gaseous species present during pyrolysis of methane, ethane and butane in a laminar flow reactor. The investigation aimed to further the understanding of the decomposition process of these fuels and the subsequent formation of aromatic rings. The pyrolysis of methane, ethane and butane were carried out in a tube reactor under laminar flow conditions and within a temperature range of 869–1213 °C. The fuels were premixed in nitrogen carrier gas at a fixed carbon atom concentration of 10,000 ppm, and were pyrolysed under oxygen-free conditions. Intermediate gaseous species were collected from within the tube reactor at different residence times using a specially designed high-temperature ceramic sampling probe with arrangements to quench and freeze the reactions at entry to the probe. Identification and quantification of intermediate species were carried out using a gas chromatography-flame ionization detector (GC-FID). During methane pyrolysis, it was observed that as the concentration of acetylene increased, the concentration of benzene also increased, suggesting that the benzene ring is formed via the cyclo trimerisation of acetylene. With all three fuels, all intermediate species disappeared at higher temperatures and residence times, suggesting that those species converted into species higher than benzene, for example naphthalene. It was observed that increasing carbon chain length lowered the temperature at which fuel breakdown occurred and also affected the relative abundance of intermediate species

Influence of Fuel Bound Oxygen on Soot Mass and Polyaromatic Hydrocarbons during Pyrolysis of Ethanol, Methyl Acetate, Acetone and Diethyl Ether

Air pollution has reached critical levels in many major industrial cities, endangering public health, deteriorating the environment, and causing harm to property and landscape. The particulate emissions (PM) from propulsion which contribute to air pollution vary greatly in size and composition, conveying carcinogenic polyaromatic hydrocarbons (PAHs) present on the particle surface. Although it has been found that replacing fossil fuels with renewable oxygen-bearing fuels reduces the mass of PM released, not much is known on how this change in fuel composition affects soot levels, PAH production, and toxicity during the pyrolysis processes that occur in combustion engines. Biofuels such as alcohols, esters, ethers, and ketones are considered to be potentially sustainable alternatives fuels and can be produced by various biological and thermochemical processes from a range of renewable feedstocks. The effects of these oxygenated functional groups on the soot mass and PAHs produced during pyrolysis in a laminar flow reactor were investigated quantitatively in this study. The 16 PAHs identified as priority pollutants by the US Environmental Protection Agency (EPA) were investigated in this research, with particular focus on the probable mechanisms for production of the most carcinogenic PAHs (group B). The oxygenated fuels were pyrolyzed at temperatures ranging from 1050 to 1350 0C under oxygenfree conditions with a constant carbon atom content in nitrogen of 10,000 ppm and at a consistent residence period. Both soot bound PAH collected on filter papers and gaseous PAHs collected on XAD resin were extracted using accelerated solvent extraction (ASE), with PAH identification and quantification carried out using gas chromatography combined with mass spectroscopy (GCMS). An effect of the oxygenated functional groups on soot mass was readily apparent, with consistently lower production of soot by methyl acetate, and which has a higher oxygen to carbon ratio than ethanol, acetone, and diethyl ether. At all temperatures except 1350 0C, methyl acetate pyrolysis yielded much lower GP PAH levels than acetone and diethyl ether, but somewhat higher than that from ethanol pyrolysis. The concentration of PP PAH per unit volume of gas is much lower than the corresponding GP PAH, which suggests that PP PAH that condensed onto particulate surface, subsequently experienced surface reaction and were therefore not recoverable during the extraction process. The production of pyrene via acenaphthylene was found to dominate at higher temperatures for all fuels, regardless of molecular structure. At 11500C the relative abundance of the soot particles was low, however, the toxicity of the soot particles formed was substantially higher at lower temperatures, particularly in the case of pyrolysis of methyl acetate soot

The analysis of performance before and after ERP implementation: a case of a manufacturing company

[EN] Machines and technology have been known for saving the efforts and so the time of the human race. Thus in the gravity of consideration to this point, companies are required to innovate their process and practices to improve productivity. The present research was conducted at ABC manufacturing company having three departments i.e. A, B, and C. The significant impact after ERP implementation in terms of time-saving has been reflected in the present research. The nature of working and nature of manufacturing is different in all the departments; that`s why each department has its business development team. The case company has implemented an industrial and financial system (IFS) in 2020 and the whole process is properly followed in IFS. In this study, the process flow of documents and time consumption on each step of obtaining approvals from various authorities is covered, and saved time after the implementation of IFS is also revealed in detail. Results indicated that, after the implementation of IFS, the company has saved 48272.5 hours in 2021 by carryingout the whole process on IFS instead of a manual approach. None of the research highlights the magnitude and percentage of saved time after the implementation of an IFS in the manufacturing industry; The present research can be the basis of motivation for any manufacturing to implement IFS.Kalwar, MA.; Khan, MA.; Phul, Z.; Wadho, MH.; Shahzad, MF.; Marri, HB. (2022). The analysis of performance before and after ERP implementation: a case of a manufacturing company. Journal of Applied Research in Technology & Engineering. 3(2):115-121. https://doi.org/10.4995/jarte.2022.17789OJS1151213

Designing a wind energy harvester for connected vehicles in green cities

Electric vehicles (EVs) have recently gained momentum as an integral part of the Internet of Vehicles (IoV) when authorities started expanding their low emission zones (LEZs) in an effort to build green cities with low carbon footprints. Energy is one of the key requirements of EVs, not only to support the smooth and sustainable operation of EVs, but also to ensure connectivity between the vehicle and the infrastructure in the critical times such as disaster recovery operation. In this context, renewable energy sources (such as wind energy) have an important role to play in the automobile sector towards designing energy-harvesting electric vehicles (EH-EV) to mitigate energy reliance on the national grid. In this article, a novel approach is presented to harness energy from a small-scale wind turbine due to vehicle mobility to support the communication primitives in electric vehicles which enable plenty of IoV use cases. The harvested power is then processed through a regulation circuitry to consequently achieve the desired power supply for the end load (i.e., battery or super capacitor). The suitable orientation for optimum conversion efficiency is proposed through ANSYS-based aerodynamics analysis. The voltage-induced by the DC generator is 35 V under the no-load condition while it is 25 V at a rated current of 6.9 A at full-load, yielding a supply of 100 W (on constant voltage) at a speed of 90 mph for nominal battery charging

Development and Comparative Analysis of Electrochemically Etched Tungsten Tips for Quartz Tuning Fork Sensor

Quartz Tuning Fork (QTF) based sensors are used for Scanning Probe Microscopes (SPM), in particular for near-field scanning optical microscopy. Highly sharp Tungsten (W) tips with larger cone angles and less tip diameter are critical for SPM instead of platinum and iridium (Pt/Ir) tips due to their high-quality factor, conductivity, mechanical stability, durability and production at low cost. Tungsten is chosen for its ease of electrochemical etching, yielding high-aspect ratio, sharp tips with tens of nanometer end diameters, while using simple etching circuits and basic electrolyte chemistry. Moreover, the resolution of the SPM images is observed to be associated with the cone angle of the SPM tip, therefore Atomic-Resolution Imaging is obtained with greater cone angles. Here, the goal is to chemically etch W to the smallest possible tip apex diameters. Tips with greater cone angles are produced by the custom etching procedures, which have proved superior in producing high quality tips. Though various methods are developed for the electrochemical etching of W wire, with a range of applications from scanning tunneling microscopy (SPM) to electron sources of scanning electron microscopes, but the basic chemical etching methods need to be optimized for reproducibility, controlling cone angle and tip sharpness that causes problems for the end users. In this research work, comprehensive experiments are carried out for the production of tips from 0.4 mm tungsten wire by three different electrochemical etching techniques, that is, Alternating Current (AC) etching, Meniscus etching and Direct Current (DC) etching. Consequently, sharp and high cone angle tips are obtained with required properties where the results of the W etching are analyzed, with optical microscope, and then with field emission scanning electron microscopy (FE-SEM). Similarly, effects of varying applied voltages and concentration of NaOH solution with comparison among the produced tips are investigated by measuring their cone angle and tip diameter. Moreover, oxidation and impurities, that is, removal of contamination and etching parameters are also studied in this research work. A method has been tested to minimize the oxidation on the surface and the tips were characterized with scanning electron microscope (SEM)

Decomposition of some hydrocarbon and oxygenated fuel molecules and subsequent formation of PAHs under pyrolytic conditions in a flow reactor

[Redacted

A CRISPR Way for Fast-Forward Crop Domestication.

peer reviewedPrecision crop breeding, using genome editing tools such as clustered regularly interspaced short palindromic repeats (CRISPR) systems to improve useful traits in crop plants, holds great potential for the future of agriculture. Using CRISPR-Cas9, recent studies have engineered domestication traits in wild-relative species of tomato crop for higher nutritive value and better adaptation to diverse stresses

Adaptive Global Fast Sliding Mode Control for Steer-by-Wire System Road Vehicles

A steer-by-wire (SbW) system, also known as a next-generation steering system, is one of the core elements of autonomous driving technology. Navigating a SbW system road vehicle in varying driving conditions requires an adaptive and robust control scheme to effectively compensate for the uncertain parameter variations and external disturbances. Therefore, this article proposed an adaptive global fast sliding mode control (AGFSMC) for SbW system vehicles with unknown steering parameters. First, the cooperative adaptive sliding mode observer (ASMO) and Kalman filter (KF) are established to simultaneously estimate the vehicle states and cornering stiffness coefficients. Second, based on the best set of estimated dynamics, the AGFSMC is designed to stabilize the impact of nonlinear tire-road disturbance forces and at the same time to estimate the uncertain SbW system parameters. Due to the robust nature of the proposed scheme, it can not only handle the tire–road variation, but also intelligently adapts to the different driving conditions and ensures that the tracking error and the sliding surface converge asymptotically to zero in a finite time. Finally, simulation results and comparative study with other control techniques validate the excellent performance of the proposed scheme

Dermatomycoses in Pakistan; an urgent need for National Surveillance Programs

Despite the rising burden of fungal infections across the globe, the World Health Organization's efforts remained questionable in fungal infection-related projects. Most of the developing countries consequently lost focus on the need for assessment and establishment of national surveillance set up or advanced technology hubs against mycological infections. The current study aimed to the determination of the local burden of cutaneous fungal infections in 2019-2021. Among 497 suspected fungal cultures, 22.5% depicted fungal growth. Among males, the prevalence of dermatomycosis was 0.75 times higher than in females. Penicillium species followed by Epidermophyton and Candida species were common among subjects of < 30 years of age. The Aspergillus spp, Penicillium spp, mucormycosis agents, and Candida albicans infections were more common among subjects 30 to 60 years of age. Aspergillus species were more commonly observed among patients > 60 of age. 22.2% of the fungal infections were Penicillium species, 9% of the infections were Aspergillus species, followed by 4.4% of Epidermophyton, mucormycosis, Candida species, and Candida albicans respectively. There is an urgent need for the establishment of national policy for the prevention of fungal disease