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Flue Gas Desulfurization (FGD) is pivotal in reducing Sulfur Dioxide (SO2) concentrations through neutralization. This study explored dry FGD modeling using Artificial Neural Networks (ANN) and Adaptive Neuro-Fuzzy Inference Systems (ANFIS). The independent parameters used were diatomite to Ca(OH)2 ratio, hydration time, hydration temperature, SO2 concentration, and sulfation temperature, while the output responses incorporated were sulfation efficiency () and sorbent conversion (). ANN simulations employed the Levenberg-Marquardt (LM), Bayesian Regularization (BR), and Scaled Conjugate Gradient (SCG) algorithms with 7 to 10 hidden cells. The sigmoid and linear functions served as trigger mechanisms. ANFIS models, utilizing grid partitioning and subtractive clustering, were trained with hybrid and backpropagation methods. Seven ANFIS membership functions were compared for the best-fit model. The computing models were critiqued using RMSE, MSE, and R2 statistical metrics. Numerical error analysis favored the ANN program, with BR exhibiting the highest R2 values (0.9987 for , 0.9986 for ). However, the SCG algorithm emerged as the most dependable model due to its lowest RMSE and MSE values. In contrast, the ANFIS model demonstrated inferior R2 values and forecasting capabilities. This investigation provided nuanced insights into dry FGD modeling, elucidating the interplay between computational methodologies and process parameters.

A comprehensive review of sodium-based flue gas desulphurisation is presented in this article. The paper provides a comparison of various sodium-based technologies with regards to sulphur removal efficiency, sorbent cost, by-product valorisation and overall process economics. More emphasis was placed on dry sorbent injection (furnace sorbent injection, economizer sorbent injection, duct sorbent injection) and semi-dry flue gas desulphurisation. Particular effort was devoted in identifying state-of-the-art technologies and potential research gaps in a summarized way. In water-scarce countries, where sodium-based technologies are more economically feasible, and duct sorbent injection processes are favourable, it is recommended to use sodium-based absorbents since they will have higher sorbent utilization and improved electrical resistivity (compared to their calcium-based and/or magnesium-based sorbent equivalents). However, the check-and-balance of the associated advantages and disadvantages are a pivotal determinant of the sorbent choice. Apart from sulphur dioxide abatement, the additional advantages of sodium-based absorbents include its high sulphur trioxide removal efficiency as well as its hydrogen fluoride and hydrogen chloride removal capability. A scarcity in literature, especially as it relates to application in the South African coal-fired power generation industry, necessitates the need for further research with particular focus on local sodium-based absorbent markets, the physiochemical properties and sulphur dioxide reduction potential of locally acquired sodium-based absorbents, modelling of sulphation reaction kinetics in semi-dry and dry application, as well as the techno-economic feasibility of sorbent based technologies for the South African power industry.

Society confronts the pressing environmental challenges posed by the pervasive presence of toxic pollutants in aquatic ecosystems. The repercussions of contaminant release extend far and wide, endangering marine life and human well-being. While various techniques such as bioremediation, filtration, and adsorption have been employed for wastewater treatment, they grapple with cost effectiveness and overall efficiency issues. Advanced oxidative processes, including photocatalysis and Fenton, have emerged as viable solutions in response to the emerging contaminants. However, the efficacy of photocatalysis largely hinges on the choice of catalyst. Their distinctive attributes, such as chemical defects and exceptional stability, make perovskite oxides a promising catalyst. These materials can be synthesized through diverse methods, rendering them versatile and adaptable for widespread applications. Ongoing research endeavors are diligently focused on enhancing the performance of perovskite oxides, optimizing their integration into catalytic processes, and exploring innovative approaches for material immobilization. This comprehensive review seeks to elucidate the most pivotal advances in perovskite oxides and their composites within the wastewater treatment domain. Additionally, it sheds light on burgeoning research trends and multifaceted challenges confronting this field, which present insights into techniques for treating the antibiotic-contaminated environment, delving into innovative strategies, green technologies, challenges, and emerging trends.

Blast furnace slag (BFS), a waste product from the blast furnace during iron extraction, has severe environmental impacts but is also rich in compounds that, if adequately extracted or recycled, could contribute to economic growth and reduce the demand for virgin raw materials. This research, therefore, seeks to investigate the effectiveness of the BFS composition before and after impregnation with potassium hydroxide (KOH) at different concentrations (10, 30, 60, and 90 %) in catalyzing the transesterification of waste cooking oil (WCO) to biodiesel. The transesterification process was optimized using a central composite design (CCD) for response surface modeling (RSM). The catalyst amount (3–11 wt%), reaction time (2–6 h), and methanol: oil ratio (10–30:1 mol/mol) were varied while keeping the reaction temperature (60 °C) and stirring speed (750 rpm) constant. The CCD generated a quadratic model that correlated with the experimental data with an R2 of 0.9545. The maximum yield obtained after model validation was 93.15 % at a methanol: oil ratio of 15:1, a reaction time of 3 h, and a catalyst amount of 5 wt% using the 30 % KOH/BFS catalyst. The biodiesel produced met the ASTM D6751 standards for fatty acid content, kinematic viscosity, density, and cloud point. The catalyst was able to sustain activity for a maximum of three cycles.

Experimental data was obtained from literature for the supercritical fluid extraction (SFE) process of Sclerocarya birrera kernel oil in supercritical carbon dioxide (CO2). The external mass transfer, diffusion, and axial dispersion coefficients were determined from the experimental values as well as the Sherwood, Reynolds, and Schmidt dimensionless consortiums. The Reynolds number ranged between 8 to 15, indicating that natural convection occurred. The Sherwood and Schmidt numbers were between 2 to 3.4 and 1.6 to 4. Although the solubility of marula oil decreased with an increase in temperature, its effective diffusivity and external mass transfer coefficient increased. However, the external mass transfer coefficient, diffusion coefficient and axial dispersion coefficient decreased with an increase in pressure due to a decrease in binary diffusivity. Even though the density of the solvent increases with pressure, which results in an increase in the diffusivity of the solute in supercritical CO2, the coefficients however decrease. The amount of extract is also amplified by the increase in solvent power.

This paper presents the findings of an experimental investigation on the performance of a laboratory-scale spray dryer involving flue gas desulfurization. Using commercial hydrated lime as a sorbent, a systematic set of experiments were performed to evaluate SO2 absorption capacity of the spray dryer. The experimentation involved accurate measurement of the spray drying characteristics, such as temperature and SO2 concentration along the spray chamber, by varying the input and output variables. Tests were done to investigate the effects of spray characteristics, i.e., inlet gas phase temperature (120–180 ℃) and calcium-to-sulfur ratio (1–2.5), on SO2 removal efficiency. The performance of the spray dryer was further evaluated based on the degree of conversion of calcium (sorbent utilization) after SO2 absorption. Results indicated an increase in SO2 removal efficiency by increasing the stoichiometric ratio and decreasing the temperature. Absorption efficiency of SO2 beyond 90% was achieved at a stoichiometric ratio of 2.5. A high degree of conversion of calcium was realized at low stoichiometric ratios, with a maximum utilization of 94% obtained at a stoichiometric ratio of 1.5. The analysis of the final desulfurization product revealed the presence of sulfite with better conversion achieved at a stoichiometric molar ratio of 1.5. A significant amount of unreacted sorbent (63.43%) was observed at a stoichiometric ratio of 2, while samples collected at a stoichiometric ratio of 1.5 had the lowest concentration of unreacted Ca[OH]2 (41.23%).

A well-designed adsorption system should meet the requirements for high efficiency while remaining cost and time effective. nanocellulose materials have a proven track record as viable adsorbent alternatives. Cellulose is a renewable raw material that can be used to develop an adsorbent for heavy metal ions removal. In this study, CNCs were modified with EDTA and used as adsorbents to remove Pb(II) and Cu (II) ions from a mixture of metal ions synthesized solution. The modified CNCs were characterized using Fourier transform infrared (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) surface area. SEM results showed that CNCs are porous, have narrow particles size, and FTIR results revealed that the functional group responsible for the lead ions removal was mainly carboxylates (-COO2-). The XRD diffraction pattern showed that the CNCs possessed the cellulose crystalline configuration. The effects of the sorbent dosage, contact time, pH, and initial on the removal efficiency of the metal cations were examined. The absorption mechanism was described via four mechanistic models: Film diffusion, Weber and Morris, Dummwald-Wagner, and Bangham. The Artificial Neural Network (ANN) model predicted the adsorption of heavy metal ions with incredible accuracy, with an adsorption capacity of 250 mg/g for Copper and 270 mg/g for lead. Film diffusion was identified as the rate-limiting process via mechanistic modelling.

Solubility data obtained from literature for Sclerocarya birrea kernel oil in supercritical carbon dioxide (CO2) were correlated using six semi-empirical density-based models viz. Chastril, del Valle and Aguilera (DVA), Adachi and Lu (AL), Sparks et al., Kumar and Johnston (KJ), and Mendez-Santiago and Teja (MST). The determination coefficient values (R2) ranged from 0.72 to 0.95. The average absolute relative deviations (AARD%) ranged from 15.53 to 0.049. A comparison was made between all six semi-empirical density-based models, and it was concluded that the MST model provided an improved and better fit than the other models investigated. After examining each of the six models under investigation, an improved model is proposed, which can characterize most of the findings taken into account about Sclerocarya birrea kernel oil yield.

Abstract Background With the increased availability of access to prenatal ultrasound in low/middle-income countries, there is opportunity to better characterize the association between fetal growth and birth weight across global settings. This is important, as fetal growth curves and birthweight charts are often used as proxy health indicators. As part of a randomized control trial, in which ultrasonography was utilized to establish accurate gestational age of pregnancies, we explored the association between gestational age and birthweight among a cohort in Western Kenya, then compared our results to data reported by the INTERGROWTH-21st study. Methods This study was conducted in 8 geographical clusters across 3 counties in Western Kenya. Eligible subjects were nulliparous women carrying singleton pregnancies. An early ultrasound was performed between 6 + 0/7 and 13 + 6/7 weeks gestational age. At birth, infants were weighed on platform scales provided either by the study team (community births), or the Government of Kenya (public health facilities). The 10th, 25th, median, 75th, and 90th BW percentiles for 36 to 42 weeks gestation were determined; resulting percentile points were plotted, and curves determined using a cubic spline technique. A signed rank test was used to quantify the comparison of the percentiles generated in the rural Kenyan sample with those of the INTERGROWTH-21st study. Results A total of 1291 infants (of 1408 pregnant women randomized) were included. Ninety-three infants did not have a measured birth weight. The majority of these were due to miscarriage (n = 49) or stillbirth (n = 27). No significant differences were found between subjects who were lost to follow-up. Signed rank comparisons of the observed median of the Western Kenya data at 10th, 50th, and 90th birthweight percentiles, as compared to medians reported in the INTERGROWTH-21st distributions, revealed close alignment between the two datasets, with significant differences at 36 and 37 weeks. Limitations of the current study include small sample size, and detection of potential digit preference bias. Conclusions A comparison of birthweight percentiles by gestational age estimation, among a sample of infants from rural Kenya, revealed slight differences as compared to those from the global population (INTERGROWTH-21st). Trial registration This is a single site sub-study of data collected in conjunction with the Aspirin Supplementation for Pregnancy Indicated Risk Reduction In Nulliparas (ASPIRIN) Trial, which is listed at ClinicalTrials.gov , NCT02409680 (07/04/2015).

Chlor-alkali process industries produce a million tonnes of brine sludge which are dumped in landfills. Brine sludge waste can be thermally modified and applied as a heterogeneous basic catalyst to synthesise biodiesel from waste cooking oil (WCO). In this work, an experimental design obtained by response surface methodology was used to study the effects of process parameters and hence, optimise the transesterification process. A quadratic model was generated to estimate the yield of biodiesel to its process variables. A biodiesel yield of value 97.8 wt % was optimally achieved using numerical optimisation method at a reaction period; methanol to oil weight ratio, a catalyst to oil weight ratio, and temperature of 1.53 hr, 29.8 wt %, 2.47 wt %, and 60.31°C, respectively. The brine sludge waste catalyst was reutilised up to four times without being deactivated. Morphological modifications of the brine sludge after calcination and transesterification were characterised using a scanning electron microscope (SEM) and X-ray diffraction (XRD). From the basic fuel properties specifications stipulated in the ASTM standard, it was found WCO biodiesel properties were within the acceptable range.

The present study aimed to explore the drivers of early marriage and teenage pregnancy in Kenya and Uganda during COVID-19 lockdown period. A systematic review design was adopted. The major online databases utilized were PubMed, Google Scholar, Uganda and Kenya Ministry of Health repositories, ScienceDirect, and Scopus. Studies that were originating from Kenya and Uganda that were publicly available in electronic format published from March 2020 to March 2022 were used. The thematic analysis identified major concepts that were drivers to the present research problem which were as follows: (1) school closure and (2) loss of income by parents. The COVID-19 containment measures introduced in the two countries were noted as major contributing factors. During the pandemic, lockdown led to school closures which meant the teenagers being idle at home with an increased opportunity to indulge in sexual risk behaviors. Schools have been noted to be a safe place protecting this vulnerable population. However, with their prolonged closure, the teenagers were exposed to sexual predators. Parents lost income, and this might have contributed to early marriages and teenagers' dependency on their sexual partners. Based on the reviewed evidence, the present study furthers the advocacy for the reduction of early marriages and teenage pregnancy, especially in the current COVID-19 pandemic era. The study calls upon the governments to intensify efforts toward the present research problem as the COVID-19 pandemic is eroding the earlier gains made within the region.

In this paper, phosphate rock has been utilized beyond its traditional role as a raw material for fertilizer production to a new potential role as a heterogeneous base catalyst for biodiesel production. The rock was thermally modified through calcination at 900 °C for 8 hrs. One factor at a time experimental design was used to vary the operating conditions of time (30–150 min), temperature (40 °C–80 °C,) catalyst concentration (1–5 wt%), and methanol to oil ratio (10–50 wt%). It was established that the optimum production conditions for maximum biodiesel yield of 93 % using this novel catalyst was achieved at reaction time 90 min, reaction temperature 60 °C, catalyst concentration 3wt% and methanol to oil weight ratio of 30 wt%. The synthesized biodiesel was compared with the raw waste oil using Fourier transform infrared spectroscopy (FTIR) to determine the efficiency of conversion from this catalyst. The catalyst modification after calcination was also analysed using this spectroscopic technique to confirm any changes in the functional groups. Biodiesel’s chemical and physical properties were measured based on the American Society for Testing and Materials (ASTM) international standards for biodiesel.

In the present study, calcined phosphate rock was used as a heterogeneous catalyst for biodiesel production from waste cooking oil (WCO). Response surface methodology was used to optimize and determine the significant process variables that affected the experiment. A 5-level-4 factor Central composite design consisting of 30 experiments was used to develop a quadratic polynomial model. The following parameters were optimized, namely, reaction temperature (40–90 °C), catalyst to oil weight ratio (1–5 %), reaction time (40–120 min), and methanol to oil ratio (10:1–18:1). Maximum biodiesel yield of 96.07 % was obtained through numerical optimization at reaction temperature 62.63 °C, catalyst to oil weight ratio of 3.32 %, reaction time 79.07 min, and alcohol to oil ratio 14.79:1. Fourier transform Infrared Spectra (FTIR) analysis was used to characterize the phosphate rock in its raw form, after calcination at 1000 °C and after the first and the fourth reuse cycle. According to the American society for testing and material (ASTM D6751), the fuel properties such as kinematic viscosity, pour point, cloud point, and density were measured and were found to be within the stipulated range.

The attributes of cost-effectiveness, reliability, consistency and better understanding, have made researchers prefer studying engine characteristics of IC engines fuelled with alternative fuels/diesel blends with computer simulation compared to conventional experimental study. For the first time, the study attempted to simulate combustion, performance, and emission characteristics of biodiesels from Canola and Sunflower oil domiciled in South Africa. The properties of biodiesel vary from one region to another depending on the local properties of the feedstock used for its production. In this study, a computer model-based C++ was used to evaluate the performance characteristics of biodiesel fuels produced from local South African sunflower and canola oil feedstocks. The developed model was validated using experimental results. The performance characteristics of biodiesel and biodiesel-diesel blends from these oils were tested in a Mercedes Benz OM 364A turbocharged four-stroke, four-cylinder direct ignition industrial diesel engine. Results show similar combustion characteristics for all the tested samples. Diesel shows a higher brake power and higher exhaust gas temperature than all the tested fuel samples. The brake thermal efficiency increases with the amount of biodiesel in the biodiesel-diesel blends. Biodiesel and its diesel blends show higher specific fuel consumption than diesel. In terms of emissions, nitrogen oxide emission was higher for biodiesel and its blends with diesel compared with diesel while smoke emission from biodiesel and its diesel blends was lower compared with diesel.

Convective drying was used to investigate the drying characteristics of human faeces. Thin-layer drying semi-empirical models were used to describe the drying characteristics of human faeces under varying conditions of temperature, air velocity and relative humidity. The drying experiments were conducted at moderate near-ambient conditions, with temperatures of 20 °C, 25 °C, 30 °C, 35 °C and 40 °C, and air flows of 0.1 m/s, 0.2 m/s and 0.5 m/s, at relative humidity of 5%, 10%, 20% and 40%, and initial moisture content of 82.2%, 78.1%, 71.7%, 71.1% and 64.2%. The experimental data curves for faeces for varying temperatures were fitted to the Newton, the Henderson and Pabis, the Page, and the Midilli-Kucuk models, while other experimental conditions were kept constant. Page model was the best fitting model, with R2 values ranging from 0.9950 to 09,977. Effective moisture diffusivity and convective mass transfer coefficient were found to vary from 8.81 × 10−8 m2/s and 1.31 × 10−5 m/s at 20 °C to 9.57 × 10−7 m2/s and 3.49 × 10−4 m/s at 40 °C, respectively. The activation energy was found to be 42.38 kJ/mol. The results presented in this study confirm that human faeces can be dried under moderate ambient conditions by using solar and wind energy. The modelled kinetics can inform the development and design of a dry sanitation system that does not require electricity or any other fuels for heating and air convection.

Manganese ores are the major raw materials utilized in the production of manganese ferroalloys. A common problem in the production of manganese ferroalloys is the lack of knowledge regarding mineralogical and metallurgical properties of manganese ores. Decrepitation, which is described as the breakage or disintegration of the ore particles upon heating, is an important quality parameter of these ores. The decrepitation Index (DI), which is the parameter used to describe the extent of decrepitation, is described as the ratio of mass of particles

The response surface methodology (RSM) was used to evaluate the influence of two independent variables namely extraction temperature and extraction pressure via literature data obtained from supercritical fluid extraction (SFE) process of Sclerocarya birrea kernel oil. The optimal (custom) option was utilised on Design Expert Version 13 to optimise the variables taken into consideration. The raw experimental data comprised of 9 experimental runs of which the temperature was varied between 40, 60 and 75 °C and the pressure was varied between 250, 350 and 450 bar. The reaction time, particle size and carbon dioxide (CO2) flowrate was kept constant at 30 kg CO2/hour for all experimental runs.

‘Hop’ (Humulus lupulus) cultivar trials were conducted at sites in three Virginia counties (Northampton, Chesterfield, and Madison) in response to demand by the craft beer industry for local ingredients. In 2016, a replicated study involving five cultivars (Cascade, Chinook, Newport, Nugget, and Zeus) was established on an 18-ft-tall trellis system at each site. Weather data influencing infectivity of downy mildew (Pseudoperonospora humuli) and powdery mildew (Podosphaera macularis), two economically important hop diseases, was collected, and to the extent possible, similar cultural practices were applied at each site. Climatic conditions favorable to P. humuli and P. macularis were present throughout the experimental period, and P. humuli infection was widespread at all sites starting from 2017. Among common pests, Japanese beetle (Popillia japonica) was the only one observed to cause significant damage. Unseasonably high rainfall in 2018 led to crop failure at all but the Northampton site, and harvesting was done at all sites only in 2017 and 2019. Yields (kilograms per hectare by weight) in 2017 were found to be ≥45% lower than second-year estimates for yards in the north and northwestern United States. Quality attributes (α and β acids; essential oil) for cones harvested from the Chesterfield site were comparable to published ranges for ‘Cascade’ in 2019, but lower for the other cultivars. More work is needed to identify or develop cultivars better suited to conditions in the southeastern United States. The influence of terroir on quality of commercial cultivars produced in the region should also be examined.

The pollution resulting from the generation of waste tires is currently causing adverse environmental problems worldwide. Heavy metals present in water is also a significant cause of health and environmental problems in developing countries. This study focuses on the development of activated carbon using waste tire pyrolytic char as a precursor and using the resulting activated carbon to treat water containing Pb2+. The results obtained from the study showed that waste tire activated carbon could effectively remove Pb2+ from aqueous solution far better than waste tire pyrolytic char. The effects of process variables: Temperature (ºC), Contact time (min), and Initial metal concentration (mg/l) were studied and the optimum operating conditions were obtained as 25°C, 120 min, and 400mg/l for the temperature, contact time, and initial metal concentration, respectively. Adsorption kinetics revealed that the experimental data gave the best fit for the pseudo-second-order kinetic model. Adsorption thermodynamics illustrated that the adsorption process was exothermic and spontaneous in nature by calculating adsorption parameters ?H, ?G and ?S as -85.57 kJ/mol.K, 4.211 kJ/mol.K, and -0.279 kJ/mol.K respectively at 298.15K.

Urine diversion toilets and waterless urinals have received much attention lately to solve sanitation challenges in water scare countries. Separating the urine at source and treating the urine and solids separately has the impact of reducing water usage and reducing the burden on wastewater treatment systems. Source separated urine can be valorised by extracting struvite as fertiliser through crystallisation. A cost-effective magnesium (Mg) source is required for the process and depending on factors such as location and availability, an Mg source may be the difference between an economically viable process and one that is not. Different kinds of sources for Mg have been investigated, but none investigated fertiliser grade magnesium nitrate (Mg(NO3)2 ). In this study, struvite crystallisation using Mg(NO3)2 was investigated. The effect of four parameters namely residence time, pH, Mg: P ratio and stirring time on yield were studied. Residence time was determined to be the most influential parameter. The optimal pH, stirring speed, residence time and Mg:P ratio were found to be 9.5, 90 rpm, 24 min and 1.5 respectively. Stirring speed was found to have the least effect on yield and a minimal effect on crystal size distribution.

The French American hybrid grape cultivars Corot noir and Arandell (Vitis sp.), and Vidal blanc and Petit Manseng (Vitis vinifera), along with different spray programs, were evaluated for potential organic production in Virginia from 2013 to 2014. Results obtained in the study demonstrate that organic wine grape production in Virginia can be achieved by using select grape cultivars and spray programs. With the exception of Vidal blanc, disease severity and disease incidence were below the threshold for maintaining healthy vines in all organically managed grape cultivars. ‘Vidal blanc’ was not sufficiently resistant to downy mildew (Plasmopara viticola), precluding it from potential organic management in Virginia. The study also demonstrated significant disease resistance in Virginia of the cultivar Arandell, released by Cornell University (Ithaca, NY) in 2013. The results suggest that the organically registered fungicide Bacillus subtilis is effective in reducing the severity and incidence of black rot (Guignardia bidwellii) and phomopsis cane and leaf spot (Phomopsis viticola). The chemistry of organically managed berries harvested in 2014 met minimum requirements for wine production with soluble solids, titratable acidity, and pH ranging from 18.7% to 20.2%, 7.6 to 8.0 g·L−1, and 3.3 to 3.4, respectively, in ‘Arandell’ and ‘Corot noir’; and 21.0% to 24.4%, 7.8 to 9.6 g·L−1, and 2.7 to 2.9, respectively, in ‘Petit Manseng’ and ‘Vidal blanc’ juice.

Biodiesel is an environmentally friendly fuel, produced by a transesterification process using homogeneous catalyst which causes water pollution and cannot be recycled. The present study utilizes industrial brine sludge waste (IBSW) as a heterogeneous catalyst in the transesterification of waste cooking oil (WCO) into biodiesel. One variable at a time design was applied to optimize the transesterification process. The process variables were varied as follows: methanol to oil weight ratio (10–50 %), reaction time (0.5–2.5 h), reaction temperature (30–90 °C) and catalyst to oil weight ratio (0.84–4.2 %). The IBSW before and after calcination and the transesterification process was characterized using X-ray fluorescence (XRF), Fourier-transform infrared spectroscopy and scanning electron microscope (SEM). Biodiesel was produced at maximum yield of 95.51 wt% at reaction time, temperature methanol to oil weight ratio, and catalyst to oil weight ratio of 1 hour, 60 °C, 30 wt%, and 2.52 wt% respectively. The FTIR and SEM results confirms that before and after the transesterification process the modification of IBSW took place. Using the ideal process conditions, biodiesel was produced and vital fuel properties such as viscosity, density, pour point and flash point were measured and were found to be within the specification as per American Society for Testing and Material (ASTM) standards for biodiesel. The reusability of the IBSW catalyst was tested by recycling and it can be established that the catalyst can be utilized up to four times without affecting its catalytic activity.

Manganese ores are the major raw materials utilized in the production of manganese ferroalloys. Decrepitation, which is described as the breakage or disintegration of the ore particles upon heating in a rotary kiln, is an important quality parameter of these ores. The Decrepitation Index (DI), the parameter used to describe the extent of decrepitation, is described as the ratio of the mass of particles

The Pacific Northwest grows the majority of hops in the United States; however, the region is experiencing an increase in the number of days with high heat. In addition, there is an increased interest in growing hops in other warmer regions of the United States. To understand how hop plants respond to high temperatures, we measured several physiological traits of six hop cultivars under a range of temperatures from 15 to 45 °C. We found that hop plants achieved maximal carbon assimilation at temperatures of 21 to 39 °C when given sufficient water. At temperatures of 41 °C and higher, all cultivars experienced declines in carbon assimilation. This was likely due to multiple effects on the cell, including damage to photosystem II (PSII), as reflected in declines in FV/FM, damage to membrane integrity as reflected in electrolyte leakage at high temperatures, and declines in Rubisco activity likely due to degradation of Rubisco activase, as reflected in declines in Vc,max. ‘Cascade’, ‘Willamette’, and ‘Southern Brewer’ may be good candidates for growing in warm climates because all experience relatively high rates of carbon assimilation at high temperatures and did not experience significant declines in FV/FM or increases in electrolyte leakage. ‘Chinook’ appeared susceptible to extreme heat stress and exhibited evidence of irreparable damage to PSII and membrane integrity at 45 °C.

Defoliation management can significantly affect subsequent grassland’s forage productivity and sustainability. To assess the type and persistence of native warm-season grass (NWSG) yield responses to changes in defoliation intensity, a five-year harvest trial was conducted, in a randomized complete block design, at Virginia State University’s research farm. Yield responses of newly established indiangrass (Sorghastrum nutans L.). Nash, big bluestem (Andropogon gerardii Vitman), switchgrass (Panicum virgatum L.) and eastern gamagrass (Tripsacum dactyloides L.) stands to second-year changes in harvest regimes were monitored. In 2012, seedlings of these native grasses were transplanted in clean-tilled plots, with 16 plants in each pot. The field was not irrigated, but broadleaf weeds were manually controlled, and all plots were mowed in August and mid-November of 2013. Starting June 2014, each plot had three harvest-strips assigned to single, two, or three cuts per year from early June to mid-October using a plot-harvester; forage weights were recorded. Based on the recorded fresh and oven-dry sample weights, plot forage DM yields were estimated. Cumulative forage biomass of all three-cut strips flipped to single-cut increased by ≥30% and >50% for big bluestem. The second-year single-cut yields also outperformed those cut thrice since the first year by 22–51%. The second-year biomass increases from single-cut strips that were cut thrice in the first year demonstrated that flipping-triggered compensatory yield responses overshadowed the first- year losses in plant vigor. The compensatory yield increases continued to, but not beyond, the third year and varied between species. The yield responses also showed that magnitudes of defoliation management–triggered NWSG growth responses depend more on growing conditions during the recovery period than its actual duration.

This study aims to improve the fuel properties limitations of biodiesel which affect the engine performance characteristics in diesel engines. A ternary mixture simplex axial design model was used to determine the fuel properties of ternary blend mixture of waste distilled engine oil, waste cooking oil biodiesel, and petroleum diesel, and comparing it with existing physical properties models. The fuel properties namely: heating value, flash point, cetane number, density, and viscosity were determined by changing the composition in the ternary mixture design. Furthermore, the experimental data of the mixture model was fitted with existing viscosity, density, heating value, and flash point models. The viscosities were fitted with the Cragoe, Bingham, Arrhenius, and Kendall–Monroe viscosity models at 40 °C respectively. The best fit of the experimental data occurred in the following descending order: Arrhenius, Kendall–Monroe, Bingham, and Cragoe with R2 values of 0.9771, 0.9529, 0.9508, and 0.6096, respectively. The density at 20 °C, heating value, flash point, and cetane number were fitted with Kay's model based on the mixing empirical equation. The results showed that these properties were well predicted by Kay's model mixing rule empirical model due to high values of R2 of 0.9880, 0.978, 0.9929, and 0.961 respectively. The viscosity, density, heating value, and flash point of the ternary blend mixtures are within the American Society for Testing and Materials (ASTM) D 6751 and ASTM D 975 specifications range.

Structural and compositional characteristics of substrate in anaerobic digestion are known to limit the hydrolysis step. This can be countered by the use of pretreatment prior to the commencement of anaerobic digestion process. In this instance pretreatment step assists in the increase of the degradability of the substrate. Thus accelerating hydrolysis and improving methane yields Ultrasonic pretreatment is a type of mechanical treatment mainly employed for surface area increase through solid particles disintegration. This is achieved by the use of grinding methods. In this work, the main objective was to investigate how ultrasonic pretreatment affects the biogas yield. Three sonication times of (10, 20, 45 min), operated at 20 MHz and an amplitude of 8 µm were used on fruit and vegetable waste inoculated with sludge.BMP tests were performed on ultrasonic pre-treated substrate, with total solids (%TS) of 17.9%, volatile solids (%VS) of 82.1 % ,moisture content of 82.1 % and C/N of 26%. The tests were performed in batch reactors, at mesophilic temperature of 35 °C. In this work, the batch time of 13 days was sufficient to complete the process of digestion. The highest cumulative methane production was 238 ±7.64 mL/g VS, which occurred at 45 min sonication time. This yield is 43 % higher than the untreated sample. 20 minutes for pretreatment sonication time, resulted in the cumulative methane production of 210.4 ±3.82 mL/g VS. Finally, sonication time of 10 minutes resulted in the least methane yield of 173 ±3.18 mL/g VS, with only 22 % increase in the yield. These results led to the conclusion that in this instance, an increase in ultrasonic pretreatment time, resulted in an increased the methane yield.

Urine diversion toilets have become popular as a means of solving the challenges in sanitation. As a result, the source separated urine must be adequately treated so that it can be disposed of safely and valuable struvite can be extracted for use as fertiliser. Struvite crystallization has been investigated for this purpose, however, for the crystallization process to be viable and economical, a cost effective yet optimal magnesium source is required. Crystallisation must have optimal yield as well as crystal size and morphology (CSD). Crystal size is an important factor in crystallisation as it affects further processing steps such as washing and filtering, therefore CSD must be controlled in crystallisation processes. In this study, synthetic urine was prepared, and struvite crystallisation experiments carried out using Magnesium Nitrate (MgNO3). The effect of parameters on CSD were investigated. Residence time was found to be the parameter with the most effect on CSD. At residence time of 10, 30 and 60 minutes, mean particle sizes were 17, 34 and 53 µm showing that with higher residence times, larger crystal sizes can be achieved. SEM analysis of the crystal showed that the resultant crystals had the typical morphology of struvite crystals.

The environmental impacts caused by the disposal of waste tires on land and impacts of metals in water is of great concern. In this study activated carbon was prepared from waste tire pyrolysis char using a chemical activation process where KOH was used as an activating agent at 600 °C in a tube furnace. The characterization techniques namely proximate analysis and X-ray fluorescence (XRF) were used. The adsorption results revealed that waste tire activated carbon (WTAC) was more effective than waste tire pyrolysis char (WTPC) on the removal of lead ions from aqueous solution. The effect of adsorption process parameters such as: adsorbent dosage and pH on adsorption of lead ions onto WTPC and WTAC were determined and optimized. A high lead ions removal efficiency was obtained at following process conditions namely: pH of 7 and adsorbent dosage of 0.25g/100ml. Adsorption isotherms studies revealed that the experimental data was best fitted with Freundlich isotherm model. The proximate analysis and XRF analysis confirmed that chemical activation of waste tire pyrolysis char took place. Keywords: Waste tire activated carbon, Adsorption, Adsorption isot

Poultry litter and fertilizers are normally added as soil amendments. The effects of poultry litter and inorganic fertilizers on three mixed-season perennial forages were studied for two years in the field to understand growth dynamics, metals, and nutrient uptake. The primary objective was to investigate the heavy metal and nutrient concentrations, biomass yield and forage potential of a cool-season forage, stinging nettle (Urtica dioica L.), relative to warm-season forages, bermudagrass (Cynodon dactylon (L.) Pers.) and switchgrass (Panicum virgatum L.). Forage cuttings and soil samples were analyzed for heavy metals and nutrients using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Total biomass yield was higher by 66% and 50% in switchgrass and bermudagrass, respectively, compared with stinging nettle for the first year. While the warm-season forages yielded more biomass over the cool-season forage, metal concentrations were significantly higher for all elements in the cool-season forage. Stinging nettle showed greater macro-nutrient uptake with 103.20 kg ha−1, 0.87 kg ha−1, 27.49 kg ha−1 and 32.08 kg ha−1 for Ca, Fe, Mg, and P, except for K with 223.51 kg ha−1 compared with 267.29 kg ha−1 and 283.96 kg ha−1 for switchgrass and bermudagrass, respectively. Heavy metals were also higher in stinging nettle but were within the allowable limits for forages, indicating its potential as a resource for forages and nutrient cycling, particularly when double-cropped with warm-season forages.

Abstract Biochar may enhance soil health in sandy soils under peach [Prunus persica (L.) Batsch] tree production. A study was initiated in the Sandhills of North Carolina by applying pine‐biochar at two different rates (5 and 10%, v/v) and types of application (incorporation to 30 cm [‐Inc] and surface [‐Sur]) in 2017. Soil organic matter (SOM) dynamics was assessed via soil organic carbon (SOC), total nitrogen (TN), permanganate‐oxidizable carbon (POXC), aggregate fractions (macro‐, micro‐aggregates, and clay + silt particles), and enzyme activities (CNPS activity) at 0–15 and 15–30 cm in 2018 and 2019. After the first year of pine‐biochar application, POXC decreased in all biochar treatments, SOC was higher in the 10%‐Inc treatment, whereas CNPS activities and macroaggregates were highest in the 5%‐Sur compared with the non‐treated control. These results suggest early changes in SOM dynamics and biogeochemical cycling and have the potential to guide producers with the long‐term application of pine‐biochar to sandy soils.

Due to recent classification as a commodity crop in North America, producer interest in industrial hemp (Cannabis sativa L.) has increased. In the Commonwealth of Virginia, there is a need to evaluate foreign-developed industrial hemp for its adaptability and to develop new cultivars suited to local climatic conditions. Eight cultivars (‘Bialobrzeskie’, ‘Canda’, ‘Fedora 17’, ‘Felina 32’, ‘Joey’, ‘Tygra’, ‘USO 31’, and ‘Wojko’) were evaluated for grain and five (‘Bialobrzeskie’, ‘Carmagnola’, ‘Fedora 17’, ‘Futura 75’, and ‘Wojko’) for vegetative biomass. An experiment carried out at the Virginia State Research and Demonstration (Randolph) farm was laid out in a randomized complete block design with three replications. The results show that cultivars differed in the cumulative growing degree days (CGDD) needed for growth phase transitions, with ‘USO 31’ having an early transition to the reproductive phase. In addition, ‘Fedora 17’ produced greater grain yield and may have the potential for greater performance with better management to improve its adaptability to local conditions. Across cultivars and years, the grain protein content averaged 241 g kg−1 and the mineral elements were at sufficient levels for animal and human nutrition. ‘Carmagnola’ produced greater biomass yield and has the potential for adoption as local fiber cultivar.

Most secondary school secretaries do management of school offices. The routine work include, arranging meeting schedules for the principal and managing school correspondences within the secondary schools. All this calls for efficiency and effectiveness in performance and to achieve so, one of the fundamental processes for almost all activities is communication. During duty performance, technologies, trainings, and appropriate communication gadgets increase the efficiency of performance of not only secondary schools staff, but achievement of school mission and plans. The objective was to establish factors that affect secondary schools secretarial staff communication ability and efficiency. The study specifically looked at how technology, school structure and channels of communication affect secretarial staff. The target population was 50 respondents and sample size of 30 secondary schools secretaries. The study used stratified random sampling and randomly picked one secretary per school by survey questionnaire. Results showed that secretarial staffs were all female, majority of them (71%) were at age between 30-55 years and (77%) of them had 6-17 years experience. Training showed that (60%) were at least college level though most of them (87%) were not trained on communication and over half (57%) of them said school needed more communication technological equipment and training for them. Communication challenges were faced by 74% with only 22% using the communication gadgets, and 80% said there were no communication policies in place. On technology, 54% have 1-3 computers in school. It was concluded that there was need to have the necessary skills and equipment for the secretarial staff to perform effectively and efficiently. It was recommended that schools buy communication technology equipment, train secretaries on them, have flexible secondary schools structure to stimulate faster flow of information and develop communication policies to guide the staff in their work.

Melatonin (N-acetyl-5-methoxytryptamine) plays important roles in plant developmental growth, especially in root architecture. The similarity in both chemical structure and biosynthetic pathway suggests a potential linkage between melatonin and auxin signaling. However the molecular mechanism regulating this melatonin-mediated root architecture changes is not yet elucidated. In the present study, we re-analyzed previously conducted transcriptome data and identified 16 auxin-related genes whose expression patterns were altered by treatment with melatonin. Several of these genes encoding important auxin transporters or strongly affecting auxin transport were significantly down regulated. In wild type Arabidopsis, Melatonin inhibited both primary root growth and hypocotyl elongation, but enhanced lateral root development in a dose dependent manner. However, the lateral-root-promoting role of melatonin was abolished when each individual null mutant affecting auxin transport including pin5, wag1, tt4 and tt5, was examined. Furthermore, melatonin acts synergistically with auxin to promote lateral root development in wild type Arabidopsis, but such synergistic effects were absent in knockout mutants of individual auxin transport related genes examined. These results strongly suggest that melatonin enhances lateral root development through regulation of auxin distribution via modulation of auxin transport. A working model is proposed to explain how melatonin and auxin act together to promote lateral root development. The present study deepens our understanding of the relationship between melatonin and auxin signaling in plant species.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by deficits in communication and relational skills, associated with repetitive verbal and motor behaviors, restricted patterns of interest, need for a predictable and stable environment, and hypo- or hypersensitivity to sensory inputs. Due to the challenging diagnosis and the paucity of specific interventions, persons with autism (PWA) reaching the adult age often display a severe functional regression. In this scenario, the Regional Center for Autism in Adulthood in Turin seeks to develop a personalized rehabilitation and enablement program for PWA who received a diagnosis of autism in childhood/adolescence or for individuals with suspected adulthood ASD. This program is based on a Multistep Network Model involving PWA, family members, social workers, teachers, and clinicians. Our initial analysis of 500 PWA shows that delayed autism diagnosis and a lack of specific interventions at a young age are largely responsible for the creation of a “lost generation” of adults with ASD, now in dire need of effective psychosocial interventions. As PWA often present with psychopathological co-occurrences or challenging behaviors associated with lack of adequate communication and relational skills, interventions for such individuals should be mainly aimed to improve their self-reliance and social attitude. In particular, preparing PWA for employment, whenever possible, should be regarded as an essential part of the intervention program given the social value of work. Overall, our findings indicate that the development of public centers specialized in assisting and treating PWA can improve the accuracy of ASD diagnosis in adulthood and foster specific habilitative interventions aimed to improve the quality of life of both PWA and their families.