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Heat of Vaporization and Refractive Index Estimation for Hydrocarbons and Petroleum Fractions based on Simple Models
No full textThe present research reports that simple two parameter and three parameter models integrating normal boiling point, specific gravity and molecular weight of hydrocarbons can effectively be used for estimation of different important properties namely heat of vaporization and refractive index. Multivariate regression analysis was employed for model development based on experimental data of pure hydrocarbons reported in literature. Subsequently, it has been demonstrated that this model can be utilized further for prediction of those properties for different petroleum fractions as well. The developed simple generalized two parameter regression-based models can predict heat of vaporization of pure hydrocarbons (C3 – C30) and petroleum fractions with wide boiling point range from 355.5 to 646.8 K with good accuracy (percentage error less than 10% for pure hydrocarbons and lower than 13% for petroleum fractions) in addition, refractive index of petroleum fractions are estimated with percentage error of less than 4.01%. Moreover, comparison results demonstrated that developed models are more accurate and simpler for practical applications in petroleum industry as compared to earlier published correlations for both pure hydrocarbons and petroleum fractions
Theoretical Investigation of the Charge Transport Properties of the DPTTA p-Type Single Crystal to the Ambipolar DPTTA-F4TCNQ Cocrystal
No full textOur research has been conducted on the charge transport properties of the single-crystal DPTTA and the cocrystal DPTTA-F4TCNQ using the density functional theory coupled with incoherent charge-hopping model. Charge mobility is primarily considered from the combination of reorganization energy and charge transfer integral, which are important parameters in model of the charge-hopping model. The reorganization energy of DPTTA in both single-crystal and cocrystal forms exhibits similar values. Consistent with the properties of super-exchange coupling and direct coupling when under the same type of coupling mechanism, it decreases with increasing distance from the core molecule. We conclude this section by using kinetic Monte Carlo combined with Einstein\u27s equation to derive the charge mobility, and find it to be consistent with the theoretical analysis. In our study, we propose corresponding theoretical guidelines for the rational realization of the ambipolarity of D-A complexes, hoping to contribute to the understanding and rational design of the basic mechanism of D-A complexes
Sensitivity Analysis of Wind Turbine Broadband Noise Estimation to Semi-Empirical Models Parameters
Get PDFThe continuous increase of energy demand and the rising concerns on climate change, are pushing the European Union decarbonization strategies and transition toward renewable based energy systems, with wind energy playing a leading role. It is therefore necessary to have a better understanding of how wind turbines (WTs) impact on their surroundings, including their noise emissions. Among the different methods to compute noise emissions of WTs, semi-empirical models are a valid choice to have a-priori estimations of noise spectra and sound pressure levels. These models are based on correlation laws for different physical mechanisms that contribute to noise generation. Popular models for dominant noise sources include the Amiet approach for inflow turbulence noise and the Lowson model for turbulent boundary layer-trailing edge noise. Determining the parameters involved in these models can be challenging, potentially leading to significant errors in noise prediction. In this study, we conducted a novel sensitivity analysis of the models by varying different parameters such as turbulent intensity and dissipation, boundary layer thickness, and temperature. The selected test case is the reference multi-MW horizontal axis wind turbine Neg-Micon 80. The results of the multilevel-multivariate analysis, involving 63,360 combinations of the input parameters, clearly demonstrate a significant dependence of these models on atmospheric turbulence parameters. Furthermore, these models exhibit an higher sensitivity to input parameters at lower frequencies of the noise spectrum, which are generally associated with higher values of sound pressure level
Geodynamics of the Caucasus – Anatolian-Arabian region and Turkey-Syria Earthquakes 2023
No full textThe activation of natural disasters in the world requires the development of new approaches to the study of geological processes, in particular, at the boundaries of lithospheric plates, characterized by earthquakes, increased seismicity, volcanism, landslide processes, tsunamis and other dangerous natural processes and hazards. Earthquake of M 7.8 struck south -eastern Turkey and north - western Syria on 6 February 2023. The M 7.8 earthquake is the largest in Turkey since the 1939 Erzincan earthquake, and the second-strongest recorded in the country, after the 1668 North Anatolia earthquake. More than 52,800 deaths were confirmed: more than 46,100 in Turkey, and more than 6,700 in Syria. It is the deadliest natural disaster in Turkey\u27s modern history. The earthquakes caused over US$100 billion in damages. The geodynamic models construction for the deep structure of natural hazards regions is an important contribution to the study of active continental margins, which is necessary for the earthquake forecast, prediction and prognosis, assessing geoecological risks and preparing population actions in the event of natural disasters and catastrophes. The Caucasus - Arabian region is a complex highly-stressed geodynamic structure, characterized by increased heat flow, high seismicity, magmatism and volcanism. The geodynamics of the Caucasus - Arabian region is determined by the collision of the Eurasian and Arabian lithosphere plates, as well as the complex history of the development of the Alpine-Himalayan belt and surrounding territories. The problem solution of geological structures formation and evolution in various complex geodynamic settings and natural hazards forecast and prognosis requires an analysis of all available geological - geophysical data, as well as the formulation and solution of problems of mechanical and mathematical modeling. Slow lithospheric deformations are simulated by models of viscous flow in multi-layered, incompressible, high-viscosity Newtonian fluid, using Navier-Stocks equation and discontinuity equation. The solution of the inverse problem of geodynamics by the direct method is developed. The first inverse problem of geodynamics was solved - the restoration of the velocity fields, pressures and stresses at the depth of the lithosphere according to the available data on the velocities on the surface. The second inverse problem of geodynamics has been posed and solved - the determination of the movement of boundaries at the depth of the lithosphere based on the given movements of the surface. The solutions obtained can be used to analyze deep geodynamic problems, and together with geothermal modeling, geological and geophysical methods and seismic tomography can serve as a reliable apparatus for studying deep geodynamics due to the formation and evolution of geological structures and the lithosphere stress-strain state researches. The solution of the problem is analyzed on the example of the Caucasus - Arabian region geodynamics. The Geodynamic concept of geoenvironment has been developed. Geodynamic models of the regions of hazardous natural processes in order to predict and prevent natural disasters and catastrophes are constructed. An algorithm for creating monitoring systems is suggested
Muscular Hypertrophic Effects of Oral Contraceptive Consumption in Women
Get PDFHormones have several actions in the body; among their effects on effector organs, they can control the volume of skeletal muscle. The excess of hormones, in this case exogenous ones, could be altering the effects of physical exercise on skeletal muscle hypertrophy, especially after the consumption of contraceptives. Thus, we have a general objective in this work to evaluate the effects of contraceptive consumption on hypertrophy in women. We sought an integrative literature review with studies within 2001-2021, using the PubMed and Scielo databases. Seven articles were selected for a complete and coherent reading for the development of this review. Given the studies analyzed in the present study, it was possible to observe that the effects of oral contraceptives may indeed influence muscle hypertrophy. However, it can assist in preserving soft tissues, avoiding the looseness of the anterior cruciate ligament (ACL). For individuals aiming to enhance lean muscle mass, particularly in high-performance contexts, it is advisable to consider alternative contraceptive methods that do not disrupt the natural hormonal system. In conclusion, the OC user group did not obtain significant gains in lean mass, but their levels of dehydroepiandrosterone (DHEA), sex hormone agglobulinal ligand (SHBG), and insulin-like growth factor (IGF1) decreased, with increasing levels of only cortisol. Thinking of high performance to increase lean muscle mass, another means of contraceptives that do not affect the physiological hormonal system should be used
Endophytic Bacteria; Diversity, Characterization and Role in Agriculture
Get PDFEntophytic bacteria have an important role in the growth process and health of the plant host. Nevertheless, also some endophytic bacteria are existing in seeds and have not been studied yet. In addition, some Entophytic bacteria are important in plant tolerance to environmental stresses. They can colonize the internal tissues of the host and are able to use a variety of different relations including symbiotic, mutualism, communalistic, and trophobiotic. They have the ability for plant hormone production like auxin, indole acetic acid, and gibberellin; also some endophytic bacteria have the ability for siderophore creation, phosphate solubilization, nitrogen fixation, protease, and hydrogen cyanide formation.. Moreover, they produce compounds that could have possible usage in drug, agriculture or engineering. They have the ability to removesoil toxins thus, improving phytoremediation and soil fertility. Further, most of endophytic bacteria are diazotrophs and associated with the Proteobacteria, and a varied range has been detected agreeing to the nifH gene which codes for nitrogenase enzyme, structures recovered from plant materials, however a limited part of these genes looks to be stated. The endophytes discussed in this review are isolated from surface-disinfested plant tissue, and that do not damage the plant. Moreover, endophytes appear to be in-between saprophytic bacteria and plant pathogens, they are either saprophytes growing to be pathogens, or extremely grown plant pathogens with protective accommodation and nutrient provisions, but not killing their host. Generally, endophytic bacteria are partial under biotic and abiotic influences, with the plant itself being one of the main prompting influences
Magnetized Seeds and Structured Water: Effects on Resilience of Velvet Bean Seedlings (Mucuna pruriens) under Deficit Irrigation
Get PDFA custom-built water generator supplied structured water (SW) for applying the deficit irrigation treatments to velvet bean plants (Mucuns pruriens). The objectives of the study were to 1) determine the effects of magnetized seed treatment on velvet bean plants, 2) determine the effects of magnetized and hydroxylated water treatments on velvet bean plants, and 4) determine the effects of deficit irrigation, using three soil moisture levels, on velvet bean plants. The optimal water-saving treatment was magnetized seeds plus 10 MT + HWT. This treatment had a 226% increase in transpiration and a 22% increase in water vapor concentration in the intercellular airspace for the low soil moisture watering schedule. The three study factors in the optimal seed and water treatment had a synchronistic effect for enhancing metabolic efficiency by increasing whole plant WUE by 87% and carbon assimilation efficiency by 66% in the low soil moisture schedule. Plants irrigated with SW water and grown from magnetized seeds had enhanced resilience to high water stress conditions by maintaining adequate levels of biologically structured water. The rapid deactivation of a suite of highly interconnected defense activities in the optimal seed and water treatments implies that the plants exhibit macroscopic coherence properties. Coherence at the macroscopic level resulted in complex synchronization between metabolic efficiency, plant health, and deactivation of a suite of regulatory defenses in plants exposed to high water stress
Community Structure, Conservation Status, and Functional Groups of Bird Species in Mbeya Range Forests, Tanzania
Get PDFThe Mbeya range forest reserves (MRFRs) of the southern highland of Tanzania are an important hotspot for biodiversity conservation. However, its avian biodiversity has hardly ever been studied. Thus, for the first time, this study presents the inventory of bird species from MRFRs, demonstrating community structure, functional group, and conservation status. The study was carried out in four forest areas (i.e., Idugumbi, Kawetire, Mount Loleza, and Muvwa) within the MRFRs. The bird survey was carried out monthly between March 2018 and June 2018. Standardised line and point counts, as well as mist netting, were used to collect data. A total of 1052 individual birds, representing 41 species and 22 families, were recorded. Relative abundance, Shannon and Simpson species diversity, and species richness were high in Idugumbi forest and lowest in Kawetire forest. Species diversity differed significantly between the four forest areas. Moreover, Idugumbi and Muvwa had relatively low species composition dissimilarity compared to other forest areas. Different bird functional groups, i.e., insectivores, granivores, nectarivores, carnivores, frugivores, or combinations of these, were recorded in MRFRs. The insectivores were twice as abundant as granivores and nectarivores. The multi–layered vegetation structure of native plants in the Idugumbi forest appears to benefit and contribute to bird communities. The study reveals that MRFRs are an important hotspot for bird species that require ecological monitoring and protection. As a result, appropriate land–use practices near MRFRs should be followed to ensure long–term avian conservation
Pesticides and Associated Impact on Human Health: A Case of Small Farmers in Southern Sindh, Pakistan
Get PDFThe unbridled use of pesticides in agriculture sector poses a serious environmental degradation problem besides, being intimately associated with public and workers health hazard. Although the use of pesticides help to considerably control diseases, hence reduce crop losses and result in better yield of the crops. Pesticides are particularly under use to improve production of crops like corn, vegetables, potatoes and cotton, although their unfavourable effects on environmental quality and human health have frequently been reported and well documented. Pesticides mismanagement starts at the local area but always exhibits local and global impacts with universal dimensions.
The study aimed at determining the extent of pesticide use and farmers’ knowledge of the pesticides and their use on the field. One hundred farmers were interviewed concerning pesticides usage patterns from amongst farmers in vegetable production area in Lower Sindh, Pakistan. Information was obtained through structured Questionnaire coupled with personal interviews. The results revealed that 27 different pesticides were used by farmers and majority of pesticides were insecticides. All pesticides used were registered by Government of Pakistan. Toxicity class of majority pesticides belonged to Class-II, which WHO classifies as moderately hazardous and one highly hazardous pesticide with the class- Ib was also being used. Okra and tomato were more affected by the insect pests. Majority of farmers relied on nicotinoid and organophosphate groups of pesticides. A considerable number of farmers had received education at middle school level only. The source of farmers knowledge of pesticide use was the pesticides dealer who advised them when to spray the crops (s). Half of farmers had no safety protection gears/tools during pesticide application and vegetable harvesting. The survey has shown some overuse, misuse and abuse of pesticides. Farmers were not aware of pesticide hazards and they lacked appropriate knowledge on safe handling and use of pesticides, which can be attributed to inadequate agriculture extension services and state of art trainings to the farmers at their door steps along with lack of education. Since these pesticides were being traditionally used by the farmers in the near by fields and on the same fields with out their deleterious effect knowledge to the farmers, soil and environment combined together as most of the farmers were not educated but also ill equipped about the knowledge of the kind/type of pesticide being used/sprayed what to talk of its chemical nature leading to harmful effects
Age-Related Decrease in Striatal DA Produces Cognitive Deficits in Male Rats
Get PDFAging is a process that presents various alterations in physiological, behavioral and neurochemical processes. It causes impairment of CNS functions which lead to changes in memory, cognition and other behavioral performances. Reports have shown that aging causes neurochemical alterations in various physiological functions. The aim of the present study was to evaluate the cognitive changes in relation to process of aging. For this 20 male rats were taken, 10 young (4-6 months) and 10 old (18-22 months). Morris Water Maze (MWM) test was performed to monitor changes in learning and memory while Object-Recognition Task (ORT) was performed to evaluate changes in cognitive function. After behavioral assessment decapitation was done and rat brain was dissected to isolate striatum. Then neurochemical analysis was performed by HPLC-EC to monitor changes in striatal DA and DOPAC levels. Results of behavioral tests showed that aged rats exhibited a significant impairment of long-term memory. While cognitive ability assessed by ORT was also impaired in aged rats. Neurochemical results showed that there was a significant decline in striatal dopamine (DA) concentration while its metabolite DOPAC was significantly increased in aged rats. Hence aging has a significant negative influence on cognitive functions. Age-related behavioral deficits may occur as a result of decline in DA levels in striatum leading to changes in memory and cognitive performance