The emission of sulfur compounds during the combustion of coal is the main cause of atmospheric pollution and poses a threat to human health and the ecosystem. Thus, elimination of sulfur compounds ...from coal before its use is compulsory, and hence, coal desulfurization has become the key solution. In the present study, ultrasonic-assisted oxidative desulfurization of coal was conducted utilizing H
2
O
2
in the presence of choline chloride/Acetic acid (ChCl/AcA) deep eutectic solvents (DESs). Three coal samples from different areas of Punjab were received for the investigation. The DES ChCl/AcA possesses sulfur removal efficiency of up to 58–64% pyritic sulfur, 54–63% sulfate sulfur, and 48–54% total sulfur from different coal samples. In addition to inorganic sulfur removal, a considerable decrease in organic sulfur 38–41% has been obtained using ultrasound-assisted oxidative desulfurization. FTIR study has shown that the treated coal samples have decreased sulfur contents as compared to untreated coal samples along with no significant change in the calorific values. These outcomes open new paths headed for more energy-effective and cleaner coal, utilizing cost-effective DESs.
Graphical abstract
Shape memory polyurethanes (SMPUs) were prepared from polycaprolactone diol 4000 (PCL 4000), 1,4-butanediol (BDO), chitin, dimethylol propionic acid (DMPA), triethylamine (TEA) and ...4,4′-diphenylmethane diisocyanate (MDI), and the structures of the synthesized materials were verified by infrared spectroscopy. The effects of chitin and DMPA contents in the polyurethane formulation on surface properties were investigated. DMPA provides function of making hydrophilic polyurethanes. The crystalline structure of chitin enhanced the hydrophobicity of the synthesized materials. Contact angle, water absorption, surface free energy, work of water adhesion and swelling behavior of the synthesized polyurethanes were affected by varying the DMPA and chitin contents. The interactions of the PU films with solvents on the surface were clearly related to the contents of DMPA and chitin in the final polyurethane formulation.
The physicochemical attributes and microbial decontamination of oils extracted from gamma-irradiated almond (Mission and Price varieties) seeds, to the absorbed doses of 2-10 kGy, have been ...evaluated. Gamma irradiation exerted no considerable effect on the proximate seed composition. The physicochemical properties such as density and refractive index of the oils, extracted from gamma-irradieted seeds, were almost unaffected; the iodine value decreased while saponification value, unsaponifiable matter and free fatty acids increased. The oxidative status and tocopherol content of almond oils were negatively affected while the fatty acid profile slightly changed due to irradiation stress. Interestingly, these effects on the oil quality attributes were more pronounced at higher irradiation doses (> 6 kGy). Besides, microbial contamination was completely eliminated in the oils irradiated to an absorbed dose of 6.0 kGy. It could be concluded from the present findings that irradiation has a considerably positive or negative effect on some attributes of the almond oil. Therefore, an appropriate magnitude of gamma irradiation should be exercised to treat almond seeds in order to retain maximum nutritive benefits.Original Abstract: Se ha evaluado las caracteristicas fisico-quimicas y la descontaminacion microbiana de aceites extraidos de semillas de almendras (variedades Mision y Price) gamma-irradiadas a dosis absorbidas de 2-10 kGy. La radiacion gamma no ejerce ningun efecto considerable en la composicion proximal de las semillas. Las caracterfsticas fisico-quimicas tales como la densidad y el (ndice de refraccion de los aceites, extraidos a partir de semillas gamma-irradiadas, permanecieron casi sin afectar; el fndice de yodo disminuye mientras que el valor de saponificacion, la materia insaponificable y los acidos grasos libres aumentan. El estado oxidativo y el contenido de tocoferoles de los aceites de almendra se vieron afectados negativamente, mientras que el perfil de acidos grasos se modifica ligeramente debido al estres de la radiacion. Curiosamente, los efectos sobre los atributos de calidad del aceite fueron mas pronunciados a dosis de radiacion mas altas (> 6 kGy). Ademas, la contaminacion microbiana se elimino por completo en los aceites irradiados a una dosis absorbida de 6,0 kGy. Se puede concluir a partir de los presentes hallazgos que la radiacion tiene un efecto positivo o negativo considerable en algunos atributos de la aceite de almendras. Por lo tanto, se debe aplicar una magnitud apropiada de radiacion gamma para el tratamiento de semillas de almendra con el fin de retener los maximos beneficios nutritivos.
Exhaust emissions of a diesel engine are considered to be a substantial source of environmental pollution. Diesel engines are mainly used in vehicles and power generation. The usage of diesel engines ...is unavoidable as they give more power and performance, but at the same time, higher usage of diesel engines leads to increased air pollution, sound pollution, and emissions to the environment. Therefore, various attempts have been made to control the harmful emissions of engines. For this reason, different devices have been made such as catalytic convertors to overcome emission problems and purify the harmful gases. In order to meet these ends, a new system was designed that would contribute to controlling the air pollution of the engines. The system is also known as an aqua silencer, and its design is somehow different but still can be used as a silencer. The newly designed emission controller was installed in a test-bed diesel engine and a total of twenty experiments were conducted with and without the new emission controller at constant speed and at constant load. During these experiments, exhaust gases were analyzed with flue gas analyzers measuring CO2, CO, NO2, NO, and PM. The study concluded that the contaminants of diesel engine exhaust gases were) controlled by the developed emission controller.
Pyrazinamide (PZA) is a key first-line antibiotic used for the short-course treatment of drug-sensitive and multidrug-resistant (MDR) isolates of tuberculosis. PZA exhibits potent action against ...semi-dormant bacilli in acidic environments. However, mutations that occur in target genes may cause technical difficulties in the diagnosis of PZA resistance during drug susceptibility testing. The objective of the current study is to identify mutations in pncAWT rpsA and rpsAWT panD genes among PZA-resistant isolates of Mycobacterium tuberculosis (MTB) circulating in the Pashtun dominant region, Khyber Pakhtunkhwa, Pakistan. We selected 18 PZA-resistant pncAWT strains from the Provincial Tuberculosis Reference Laboratory (PTRL) Khyber Pakhtunkhwa to investigate mutations in the coding region of rpsA and panD genes. The experiments were repeated for drug susceptibility testing using MGIT 960 automated system. In addition, eighteen PZA-resistant rpsA genes along with 5 susceptible strains and one H37Rv strain were sequenced. All 18 isolates were PZA-resistant. The majority of these isolates exhibited multidrug resistance (MDR) (13/18). We identified 14 non-synonymous and one synonymous mutation in the coding region of rpsA in 11 strains. All mutations were scattered throughout the gene and not reported previously. Further, we did not identify any mutation in 7 rpsAWT panD genes. Mutations in rpsA but not in panD occur in PZA-resistant pncAWT MTB isolates circulating in Khyber Pakhtunkhwa, Pakistan.
This paper proposes a novel hybrid model for an internal combustion engine, with the power generated due to combustion as the input and the crankshaft speed fluctuations as the output. The individual ...cylinders of the engine are considered as subsystems for which a nonlinear model, based on the physical principles, is derived. The proposed model is linearized at an operating point, and a switched linear model is formed. The simulation results of the proposed model are validated by matching the results with the experimentally observed data. Using the properties of the validated model, it is shown that the crankshaft speed variations observed in the engine are a Markov process. A novel algorithm that is based on the Markov chain is proposed to detect the misfire in the spark ignition engines. In the ensuing engine rig experiments, an igniter misfire is introduced in the system and is successfully detected. The analysis of the data shows that the engine also has an air leakage in a cylinder (a developing misfire), which is experimentally confirmed later.
Automotive engine functions are entirely dependent on installed sensors performance. Any malfunction in the sensors can lead to degraded engine efficiency. This manuscript presents a novel scheme to ...devise virtual sensors for health monitoring of engine air intake path sensors. The proposed scheme assists in: Sensing of critical immeasurable parameters like Volumetric and Combustion efficiency, development of Virtual Sensor from manifold pressure dynamics for rotational speed and vice versa, Health Monitoring of the manifold pressure and crankshaft sensor. For the suggested scheme, two robust second-order sliding mode observers are employed that require two state mean value engine model based on inlet manifold pressure and rotational speed dynamics. The proposed methodology has the potential of online implementation on any automotive engine after minor tuning. In this paper, the procedure is customized for 1.3 L gasoline engine sensors: Manifold Pressure and Crankshaft sensor. The implementation results demonstrate that all the three mentioned tasks are accomplished efficiently.
PDF
