Net Yield Research Articles

Life cycle assessment and cost-benefit analysis of internal-stack trickling bio-electrochemical reactor: an evaluation for commercial viability

ABSTRACT The present study reports a detailed life cycle assessment and cost–benefit analysis of a commercially viable Internal-Stack-Trickling Bio-Electrochemical Reactor (IS-TrickBER). IS-TrickBER used wastewater as a feedstock and converted that wastewater through electrochemical methods into low-grade fertilizer and produced electricity. IS-TrickBER was observed for its performance in terms of power output and wastewater treatment. IS-TrickBER exhibited up to 4.2 Wh net energy yield while treating 84.84L wastewater per day along with 92.17% COD removal and 38.23% Columbic efficiency during the operational run with real municipal wastewater. Based on daily net energy yield, up to 1457.6Wh yearly net energy yield can be expected. A comprehensive start-to-end life cycle assessment study associated with the manufacturing, and operational phases of IS-TrickBER was also conducted to ascertain its impact on the environment. The environmental impact through air emissions during the manufacturing stage can be minimized by changing the plastic balls used as packing material in the reactor. A detailed cost–benefit analysis was also conducted to understand its economic viability. Cost–benefit analysis of IS-TrickBER, based on net energy yield, shows that IS-TrickBER could compensate its installation cost within a few years. IS-TrickBER performed well in eliminating the chemical load of wastewater and simultaneous electricity generation. Due to its scalability, compactness, and low maintenance, IS-TrickBER can be a suitable candidate in real-time wastewater treatment.

Identification of conservation priorities in the major basins of Central Asia: Using an integrated GIS-based ordered weighted averaging approach

Ecosystem services (ESs) provided by the major basins of Central Asia are critical to human well-being and have attracted the attention of the international community. The identification of conservation priorities is of great significance for the maintenance and protection of key ESs. In this study, we quantified the spatiotemporal changes of net primary productivity (NPP), soil conservation (SC), water yield (WY) and habitat quality (HQ) in the major basins of Central Asia from 1995 to 2015. In addition, a GIS-based ordered weighted averaging (OWA) multi-criterion valuation method was adopted to identify potential conservation areas under 11 scenarios. Conservation priorities were determined by comparing the conservation efficiency under each scenario. Then, a broad range of indicators were considered to distinguish the driving factors affecting ESs in conservation priorities. The results show that the average conservation efficiency in the Issyk-Kul Basin was the highest, followed by the Am Darya Basin, Ili-Balkhash Basin and Syr Darya Basin. We observed that the conservation efficiency of the four ESs declined continuously in the Ili-Balkhash Basin from 1995 to 2015, while it changed steadily in the other three basins. Correlation analysis indicated that natural factors (e.g., precipitation and topography) were the main driving factors of WY, SR and NPP in conservation priorities, while HQ was more affected by socio-economic factors (e.g., population density and both cropland and urban percentages). The identification of conservation priorities and their driving factors plays an important role in ensuring the ecological security of the lower reaches, regulating the regional water balance and stabilizing the climate pattern.

How valuable is the option to defer Uganda's crude oil production?

Our study contributes to the limited literature on real options valuation of Africa's oil investments. We establish binomial lattices to assess the value of the option to defer crude oil production in Uganda. We assume that oil prices follow a Geometric Brownian Motion (GBM) stochastic process. In our base case, we find that deferring production by another year adds value of $0.9 billion to the oil project. The value of the option to defer production particularly increases at lower crude oil prices amidst higher crude oil price volatility. When the rate of net convenience yield is high and the oil price is high, the value of the option is lower. At low oil prices, increases in cost inflation result in rejection of the project. We conclude that the Uganda oil project is generally profitable, and that deferring oil production is justified except in the cases where the net convenience yield or cost inflation is high.

Nutrient loading and farm characteristics of giant gourami fish aquaculture systems in Lake Maninjau, Indonesia: basic knowledge of production performance

Background Aquaculture systems for giant gourami, Osphronemus goramy Lacepède (1801), have significantly improved fish production yields and food security in Indonesia. However, these systems also cause serious problems in terms of eutrophication in waterbodies. This study analysed the nutrient loading and farm characteristics of giant gourami in floating cages in Lake Maninjau. Method A total of 20 floating cages were used to record these nutrients in feed supply, female and male juvenile fish, dead fish and harvested fish to estimate nutrient loading. Data on the harvested fish, production cycle, stock number and cage capacity were used to estimate the stocking density, feeding rate, feed efficiency, and net fish yield, and the relationship between feed supply and nutrient loading and farm characteristics was analysed by least squares regression methods. Results A total of 20 floating cages released nutrients into waterbodies at an average rate of 236.27±60.44 kg/cycle for C, 84.52±20.86 kg/cycle for N and 8.70±3.63 kg/cycle for P. On average, fish production for each floating cage (±SD) was 1226±282 kg wet weight/cycle, and the net fish yield was 12.63±2.82 kg/m 3/cycle. Survival rates ranged from 86.33 to 95.27%/cycle. The production cycles varied from 160 to 175 days with feed conversion ratios between 1.60 and 1.75, feed conversion efficiencies were between 0.58 and 0.63. The production parameters that had strong relationships with the net fish yield were feed supply ( r 2=0.960), stocking rates ( r 2=0.924) and feeding rates ( r 2=0.961). In contrast, the length of the production cycle was not strongly related to the net fish yield ( r 2=0.187). Conclusion Nutrient loading from the supplied feed was greater than that from the harvested fish, juvenile fish and dead fish. Increasing the net fish yield in floating cages was better predicted by the stocking densities and feeding levels than by the other factors.

Hydromechanical behavior of unsaturated soils: Interpretation of compression curves in terms of effective stress

This state-of-the-art paper on the hydromechanical behavior of unsaturated soils focuses on the interpretation of the compression curves of unsaturated soils in terms of effective stress, with the goal of understanding the relative impacts of suction on the effective stress, net yield stress, effective yield stress and slope of the virgin compression line (VCL) during a monotonic increase in net stress. A database of compression curves was compiled for both high and low plasticity fine-grained soils under a wide range of suctions, isotropic or oedometric stress states, drainage conditions (constant suction or constant water content) and preparation techniques (impact compaction, static compaction, consolidation from slurry). Most of the compression curves plotted in terms of effective stress revealed a consistent hardening response with increasing suction and a slight suction dependency on the slope VCL. Interpretation of the compression curves in terms of effective stress led to load-collapse curves with a similar shape for a wide range of soils. Most soils evaluated had a greater rate of increase in effective yield stress with suction than the rate of increase in suction stress with suction, implying that these compacted soils may be susceptible to collapse upon wetting. Inconsistent trends were observed in some studies, which were attributed partially to natural variability but also experimental issues and limitations on the range of conditions investigated. Accordingly, recommendations are provided for future studies on the compression curves of unsaturated soils to ensure that results can be clearly interpreted in terms of effective stress.

Diurnal and seasonal CO2 exchange and yield of maize cropland under different irrigation treatments in semiarid Inner Mongolia

Different irrigation treatments in plants significantly influence CO2 emissions. This study investigated the net ecosystem CO2 exchange (NEE) and yield of maize cropland under different irrigation treatments to determine the optimal irrigation treatment at different maize growth stages. Different degrees of water deficit irrigation were carried out in four fields: full irrigation, 100% evapotranspiration (ET); moderate deficit irrigation, 65% ET; and severe deficit irrigation, 40% ET. Automated static and dynamic chambers were used to measure CO2 fluxes. We found that NEE showed a “V” -shaped trend during the day and slowly declined at night. The light response parameters were calculated using the rectangular hyperbola model, and the leaf area index accounted for 85% of the light use efficiency. In the late vegetative stage, severe deficit irrigation led to a reduction in CO2 emissions but significantly reduced the crop growth rate (p < 0.05). In the reproductive stage, full irrigation not only reduced CO2 emissions but also significantly increased the crop growth rate. In the maturation stage, moderate deficit irrigation reduced CO2 emissions, and the crop growth rate decreased compared with full irrigation, but the decrease was not significant (p > 0.05). Compared with full irrigation throughout the growth period, full irrigation in the reproductive stage and moderate deficit irrigation in the late vegetative and reproductive stages both increased the maize carbon sink capacity and light use efficiency at higher leaf area index, and the harvest index did not decrease significantly. However, inadequate irrigation in the reproductive stage or severe deficit irrigation in the late vegetative and maturation stages significantly reduced the maize harvest index. Thus, full irrigation during the reproductive stage, and moderate deficit irrigation during the late vegetative and reproductive stages were the optimal irrigation strategies for saving water, reducing CO2 emissions and ensuring a satisfactory maize yield.

Net Energy Balance and Fuel Quality of an Alley Cropping System Combining Grassland and Willow: Results of the 2nd Rotation

With the central aim to reduce greenhouse gas emissions, agroforestry systems have become popular because they can provide biomass for bioenergy conversion and thus help replace fossil energy. This article compares the net energy balances of three biomass conversion techniques for an agroforestry system consisting of willows and two types of grassland biomass as well as separate stands of grassland and willow. The period of investigation was the second willow rotation (4–6 years after establishment). The biomass conversion techniques included combustion of hay (CH), integrated generation of solid fuel and biogas from biomass (IFBB), and anaerobic whole crop digestion (WCD). Compared to the first rotation (years 1–3), the net energy yield of the willow stands significantly increased. Nevertheless, the separate stand of willow had higher net energy yield than the agroforestry system. The IFBB technique led to an improvement in solid fuel quality through demineralization. CH and IFBB provided higher net energy yields than WCD.

Emergy-based method for evaluating and reducing the environmental impact of stamping systems

The stamping industry is critical in the automotive and aerospace industries, and the environmental impacts and sustainability of stamping systems have attracted considerable attention. To analyze the environmental impact and sustainability of stamping systems quantitatively, this paper presents an emergy-based evaluation method considering all the associated environmental impact factors of a pressing workshop including material and energy consumption, waste flows, time and mass losses, and processing costs. On the basis of analyzing the stamping processes and sustainability, this method comprises data collection, emergy based sustainability evaluation model and the development of sustainable evaluation indexes and systems. Based on the proposed method, the environmental impact of an industrial vehicle stamping workshop was evaluated. The results show that the net emergy yield ratio of the stamping system was greater than 2, and the waste emergy output ratio was very low, indicating that the system had high productivity levels, high yields, and low pollution discharge rates. However, its sustainability index was less than one owing to its high energy and material consumption during the production processes. To reduce the environmental impact of this stamping system and improve its sustainability, we investigated the potential improvements that could be achieved in energy consumption, productivity, and environmental impact by implementing energy-saving scheduling in the stamping workshop. The results show that the corresponding net emergy yield ratio and sustainability index of the system were both improved. The proposed emergy-based method could be used to quantitatively evaluate the environmental impacts and sustainability of stamping systems and facilitate efforts to reduce the environmental impacts of pressing workshops while improving their productivity and economic profitability.

Vertical microclimate heterogeneity and dew formation in semi-closed and naturally ventilated tomato greenhouses

The extent of the vertical microclimate heterogeneity inside a greenhouse is mostly unknown, and it can strongly affect plant production and yield quality. Tomato crop was grown in a semi-closed greenhouse equipped with horizontal ventilation and sidewall curtains, which were only opened depending on microclimate conditions; and a naturally ventilated greenhouse equipped with sidewalls curtains that were kept open. Both greenhouses had a 1,000-m2 area and a net size of 50-mesh, and were located in an arid climate zone in Israel. Vertical profiles of CO2 concentration, actual vapor pressure, air, leaf and soil temperature, net CO2 assimilation rates, stomatal conductance, and total fruit yield, fresh mass, and quality were monitored in both greenhouses for 13 days, in January 2018; CO2 concentration, actual vapor pressure, and air and soil temperature were additionally monitored in the semi-closed greenhouse for seven days in December 2016, when the ventilation was inoperative, and in December 2017, with ventilation. The vertical air temperature gradient, along with the colder microclimate inside the naturally ventilated greenhouse, led to a lack of plant uniformity and yield loss. Closing the side curtains in the fanned semi-closed greenhouse had a beneficial effect on yield, however, with mixed results for quality, due to the higher air temperature and lower carbon dioxide levels at the upper canopy. Horizontal air circulation in the semi-closed greenhouse increased transpiration and assimilation, and increased dew occurrence at night, but did not reduce the vertical heterogeneity. Significant vertical gradients affect plant physiology, and closing the curtains in winter cultivation in semi-arid/arid climates has the potential to improve fruit yield and quality. However, it must be coupled with proper air circulation and, preferably, with CO2 enrichment, or careful management of natural ventilation through side curtains, in order to maximize CO2 replenishment while minimizing heat losses.

An Economic Study of the Food Gap of Wheat in Egypt to Face some Crises.

The research aimed at estimating the size of the food gap of wheat in Egypt during the period (2000-2019), estimating the most important factors that affect it, and evaluating the price policy affecting wheat production, where the research relied in statistical analysis on some descriptive and quantitative statistical methods. The results showed an increase in the area of wheat and the quantity produced during the period (2000-2019) with an annual growth rate of about 1.62%, 1.71% respectively, the results also showed an increase in the quantity of imports, consumption and the wheat gap at annual rates of about 0.44, 0.523, 0.385 million tons, representing about 5.2%, 3.4%, 5.3% of the average of about 8.52, 15.32, 7.23 million tons respectively, during period (2000-2019). the self-sufficiency ratio decreased at an annual rate of about 0.86%, representing about 1.61% of the average period of about 53.5%.The food security coefficient declined from 0.35 as an average for the period (2006-2012) to 0.28 as an average for the period (2013-2019). This may be due to low supply price and the agricultural policy's failure to keep pace with the level of population growth and high prices, which negatively affected on food security during that period. The results showed that the net yield of feddan of wheat in the previous season was the most important variable affecting the cultivated area of wheat. It was also found that the agricultural price policy was in the disadvantage of wheat producers during the period (2015-2020).

Total returns to single‐family rentals

AbstractThe market value of U.S. single‐family rental assets totals more than $2.3 trillion. We provide the first systematic analysis of total returns to single‐family rentals in a long, broad, and granular panel. Total returns are approximately equalized across U.S. cities at 8.5%, similar to average equity returns. On average, net rental yields and house price appreciation each contribute half total returns. However, they are negatively correlated in the cross section of cities. High‐price‐tier cities accrued more capital gains, whereas low‐price‐tier cities had higher net rental yields. Within cities, lower‐price‐tier ZIP codes have higher total returns.

Emergy-based environmental impact evaluation and modeling of selective laser melting

Additive manufacturing (AM) technologies, such as direct laser and selective laser melting (SLM) manufacturing, allow the fabrication of functional products with high added value. This paper proposes an emergy-based method for evaluating the environmental impact and economic cost of the SLM manufacturing process while considering the environmental flows (materials, energy, and wastes) and economic factors (time, costs, and quality). By analyzing the emergy flows in an SLM system, sustainable evaluation indexes are developed to estimate its sustainability level. Then, the method is applied to analyze the environmental impact and economic cost of the SLM of a part. The results show that the cost of the process for a single part is high, the net emergy yield ratio of the SLM system is low, and its environmental load rate is very high. The sustainability indexes of the system indicated a high environmental impact and low production efficiency. However, the waste emergy output ratio of the system was very low, which reflected the near-net-shape characteristics of SLM, indicating a high sustainability potential. The results of this study are expected to contribute to increased sustainability and optimization of SLM.

Economics of Southern Pines With and Without Payments for Environmental Amenities in the US South

During the early 1900s, nearly 37 million hectares of land in the Southern United States were under longleaf pine (Pinus palustris) relative to the current area of 1.6 million hectares. This study compares the economics of southern pines (longleaf, loblolly (Pinus taeda), and slash (Pinus elliottii)) to facilitate the decision making of family forest landowners and design suitable financial incentives for increasing the area under longleaf pine in the region. We simulated six growth and yield scenarios for selected southern pines over three site indices in the Lower Coastal Plain of South Georgia. We estimated land expectation values (LEVs) of each scenario for the three cases, i.e., payment for forest products, payment for forest products and net carbon storage, and payment for forest products, net carbon storage, and net water yield. Our findings show that pine straw income significantly increases the LEV of longleaf pine. The financial risk of growing longleaf pine is lower than that of other southern pines. Existing financial support through various governmental incentives or additional monetary support for ecosystem services provided by longleaf pine ecosystems is needed to increase the area under longleaf pine in the Southern United States, in general, and in South Georgia, in particular. However, a need exists to reevaluate the conservation values provided by longleaf plantations considering expected shorter rotation ages due to the income provided by pine straw markets in Southern United States.

Evaluating zooplankton in traditional and split‐pond systems for raising golden shiners, Notemigonus crysoleucas

AbstractWe hypothesize for golden shiners, Notemigonus crysoleucas, raised in split‐ponds (SPS), that the waste treatment unit (WTU) would be a zooplankton refuge. To examine this hypothesis, a 6‐week study was conducted in six traditional earthen ponds (TEP) and six SPS (each 0.04 ha) stocked with adult golden shiners at 450 kg of fish/ha. Fish were fed a commercial feed at 3% body weight daily in three ponds (FED) of each pond type, while in the remaining ponds fish had access to natural foods only (UNF). Zooplankton samples were collected daily for five consecutive days from three locations in each TEP and from three locations each within the fish culture unit (FCU) and WTU of SPS. Net yield and survival were not significantly different among the treatment groups. Survival was severely impacted by depredation from birds and herpetofauna. Fish in SPS‐UNF ponds had lower condition factors, relative weight, whole‐body fats, and gonadosomatic index compared to the other treatment groups. Zooplankton number/mL were significantly higher in the TEP (both FED and UNF) when compared to other treatment groups. There was not enough evidence that the WTU being devoid of fish may serve as a refuge for larger zooplankton.

Nutrient loading and farm characteristics of giant gourami fish aquaculture systems in Lake Maninjau, Indonesia: basic knowledge of production performance.

Background Aquaculture systems for giant gourami, Osphronemus goramy Lacepède (1801), have significantly improved fish production yields and food security in Indonesia. However, these systems also cause serious problems in terms of eutrophication in waterbodies. This study analysed the nutrient loading and farm characteristics of giant gourami in floating cages in Lake Maninjau. Method A total of 20 floating cages were used to record these nutrients in feed supply, female and male juvenile fish, dead fish and harvested fish to estimate nutrient loading. Data on the harvested fish, production cycle, stock number and cage capacity were used to estimate the stocking density, feeding rate, feed efficiency, and net fish yield, and the relationship between feed supply and nutrient loading and farm characteristics was analysed by least squares regression methods. Results A total of 20 floating cages released nutrients into waterbodies at an average rate of 236.27±60.44 kg/cycle for C, 84.52±20.86 kg/cycle for N and 8.70±3.63 kg/cycle for P. On average, fish production for each floating cage (±SD) was 1226±282 kg wet weight/cycle, and the net fish yield was 12.63±2.82 kg/m 3/cycle. Survival rates ranged from 86.33 to 95.27%/cycle. The production cycles varied from 160 to 175 days with feed conversion ratios between 1.60 and 1.75, feed conversion efficiencies were between 0.58 and 0.63. The production parameters that had strong relationships with the net fish yield were feed supply ( r2=0.960), stocking rates ( r2=0.924) and feeding rates ( r2=0.961). In contrast, the length of the production cycle was not strongly related to the net fish yield ( r2=0.187). Conclusion Nutrient loading from the supplied feed was greater than that from the harvested fish, juvenile fish and dead fish. Increasing the net fish yield in floating cages was better predicted by the stocking densities and feeding levels than by the other factors.

The Potential of Soilless Culture Systems in Producing Tomato and Cucumber under Greenhouse Conditions

Aims: Assess The sustainable production of tomato and cucumber under greenhouse conditions for meeting the challenges of natural resources shortage, food security and economic.&#x0D; Study Design: Two experiments performed in complete randomized blocks with three replicates.&#x0D; Place and Duration of Study: Central Laboratory for Agriculture Climate (CLAC), Agriculture Research Center, Egypt, during two autumn seasons of 2018 and 2019 (tomato) and two spring seasons of 2019 and 2020 (cucumber).&#x0D; Methodology: Different soilless culture systems for producing tomato and cucumber under greenhouse were investigated: Hydroponic systems (Nutrient film technique (NFT) and deep flow technique (DFT)); and substrate systems (Dutch bucket, pot, container, and horizontal bag). Vegetative characteristics, yield parameters, N, P, and K contents, and environmental impact assessment were measured. &#x0D; Results: Substrate systems gave the highest vegetative growth characteristics, yield parameters, N, P and K contents of tomato and cucumber leaves, as well as the highest power use efficiencies compared to hydroponic systems. Container and bags systems gave the highest results of tomato and cucumber vegetative growth, respectively, but the highest yield and net profits records belonged to bags and pots respectively. Bags substrate system gave the highest net profit yield (10.1Kg/ plant and 21881 LE / greenhouse) of tomato plant under plastic house followed by container system that presented the highest yield (10.6 Kg/ plant) but the total cost mainly substrate cost contributed to reduce its net profit yield. While for the highest yield and net profit of cucumber, the pots system (8.1Kg/ plant and 13243 LE / greenhouse) followed container system (7.65Kg/ plant and 9045 LE / greenhouse) and bags system (7.15Kg/ plant and 10270 LE / greenhouse) were recommended. The lowest yield, the highest average power use, cost and efficiency and lowest total cost were estimated by NFT system in both of tomato and cucumber investigations.&#x0D; Conclusion: The substrate systems presented more sustainability for tomato and cucumber production under plastichouse conditions. Bags substrate system gave the highest net profit yield of tomato plant under plastic house followed by container system that presented the highest yield but the total cost mainly substrate cost contributed to reduce its net profit yield. While for the highest yield and net profit of cucumber, the pots system followed container system and bags system were recommended. The lowest yield, the highest average power use, cost and efficiency and lowest total cost were estimated by NFT system in both of tomato and cucumber investigations.

Comparison of net fish yields in pond cultured Nile tilapia (Oreochromis niloticus L.) fed on peanut-based meals as alternatives to dietary fishmeal

Although net yield directly relates to actual production at harvest, feeding trials aimed at replacing dietary fishmeal in cultured fish have largely ignored the performance indicator. A 16-week experiment aimed at comparing Net Fish Yields in Nile tilapia fed on peanut-based meals as alternatives to dietary fishmeal took place at Busoga University farmland in Eastern Uganda. Earthen ponds of size 4.0 x 3.0 x1.0 for length, width and depth respectively were used for culturing the experimental fish. Each of the 16 pond units were stocked at a density of 48 Nile tilapia fingerlings of initial live weight of 21.95 grams. Iso-nitrogenous diets containing 30% and 25% Crude Protein (CP) for the first 12 and last four weeks respectively, were used during the trial. Dietary treatments included the fishmeal (FM)-based diet and two peanut-based diets. The latter consisted of peanut meal (PNM)-based diet and mixed plant meal (MPM)-based diet in a ratio of 50:50. The commercial feed (CF) for grow-out Nile tilapia containing 25% CP acted as a control diet. NFYs of 5668 and 5624 kilograms per pond unit for Nile tilapia fed on the MPM and FM-based diets respectively, showed no significant difference (p>0.05). On the contrary, NFY of 4819 kilograms characteristic to the PNM-based diet was the lowest and significantly poorer (p

Effects of Different Fish Diets on the Water Quality in Semi-Intensive Common Carp (Cyprinus carpio) Farming

Semi-intensive common carp (Cyprinus carpio) farm technology uses several feed types affecting the growth performance; however, we know less about their long-term effects on water quality. Herein, we evaluated the effects of three commonly used feeds—moderate levels of fish meal and fish oil feed (FF), plant meal and plant oil feed (PF), and cereal feed (CF) on the nutrient (total nitrogen (TN), total phosphorus (TP) and organic matter (OM)) content of the pond water. The experiment was carried out over three consecutive years from juveniles to market-sized fish. The type of feed affected the net yields, but generally, it did not affect the water quality. The year of sampling, however, was a significant factor affecting TN, TP, and OM, whose concentrations decreased during the three years. Our findings highlight that the age of the stocked fish on water quality has a more pronounced effect than the nutrient profile of the supplementary feed. Additionally, the plant-based feed could provide comparable net yields as the fish meal-based feed without additional nutrient loading in the water column, reinforcing the sustainability of alternative feeds in semi-intensive carp farming.

Carbonization of Cellulose in Supercritical CO2 for Value-Added Carbon

Abstract In this paper, carbonization of biomass in the presence of supercritical CO2 is investigated to obtain carbon solids with enhanced properties and potential to provide a sustainable pathway for high-value solid products which are currently resourced from expensive and carbon driven fossil-fuel routes. Carbonization of cellulose was carried out in supercritical CO2 at temperatures of 523 K and 623 K at ∼100 bar pressure in a stirred reactor for 1–8 h of residence times. The obtained solid residue was characterized for morphology using scanning electron microscopy (SEM), surface graphitization using Raman spectroscopy, thermal stability using thermogravimetric analysis (TGA), and crystallinity using powder X-ray diffraction (XRD). The solid chars were found to be dominated by clusters of microspheres (&amp;lt;5 μm), especially at temperatures of 623 K. Raman spectroscopy revealed the formation of graphitic crystallite units connected by sp3 carbons (i.e., aliphatic) suggesting significant graphitization. G-band peak ratio was found to be highest for a residence time of 5 h for both the temperatures. TGA data revealed that higher carbonization temperature led to higher thermal decomposition peaks of the chars. The peak value of thermal decomposition ranged between 700 and 800 K for char obtained at 523 K and between 750 and 900 K for char at 623 K. The values were significantly higher than the decomposition peak cellulose at ∼610 K. Proximate analysis results revealed significant increase of fixed carbon content compared with cellulose. Fixed carbon to volatile content ratios revealed increase from 0.052 in cellulose to values ranging from 1.4 to 4.3 making these chars similar in character to coal (with ranking of bituminous coal and petroleum coke). The net yield of solid chars from carbonization was around 50–66% depending upon the extent of carbonization. These results suggest this pathway to produce high yields of high-quality carbon solids with low volatile content, high thermal stability, and significant graphitization. The graphitized carbon offers potential applications in catalysis, electrode materials, pollutant absorption, and energy storage and solid fuels while avoiding drying to remove moisture unlike pyrolysis.

A Comparative Economic Study of Tomato Production by Hydroponics and Conventional Agriculture (With Soil) in Greenhouses: A Case Study in the Nubaria Region

One of the most important challenges and obstacles faced by tomato farmers in the new lands is the scarcity of productive resources and their high cost, especially the suppliers of fresh water and arable land, which negatively affects the net yield. Therefore, this research paper aims to make a comparison between tomato production using traditional greenhouses (with soil) and using Hydroponics technology in the new lands with the research sample, aiming to measure the effect of using hydroponics in agricultural greenhouses on the most important indicators of economic returns, by studying and analyzing the cost components of the two production types and studying the most important productive, economic and financial indicators.