Percent Moisture Content Research Articles

Artificial root exudates restore microbial functioning in a metal contaminated, barren, inactive soil

Restoring enzyme function in barren, brownfield soils using green strategies can improve microbial functioning and enable phytoremediation. It is known that adding simple, readily metabolized substrates secreted by growing plant roots (root exudates) or a laboratory prepared solution of root exudates (artificial root exudates) can stimulate soil microbial function. It is not known whether and how well this strategy works in a contaminated, low functioning soil from an industrial barren site because contaminants in the barren soil might inhibit microbial survival and functioning, or the microbial community might not be adapted to functionally benefit from root exudates. The objective of this study was to determine whether artificial root exudates stimulate microbial function in a barren soil. We collected soils from a barren brownfield (25R) site and an adjacent vegetated brownfield site (25F), with low and high enzyme activities, respectively. We subjected both soils to three treatments: switchgrass (native to the site), artificial root exudates, and a combination of switchgrass and artificial root exudates. We measured enzymatic activity, plant growth, soil moisture, organic matter content, and easily extractable glomalin content over 205 days. By day 157, artificial root exudates increased the phosphatase activity by 9-fold in previously vegetated brownfield soil and by 351-fold in barren brownfield soil. When exudates were added to the barren soil, the plant shoot mass was higher (52.2 ± 2.5 mg) than when they were not (35.4 ± 3.6 mg). In both soils, adding artificial root exudates significantly increased the percent moisture, organic matter, and glomalin content. Treating contaminated, barren soil with artificial root exudates resulted in increased soil microbial function and improved soil properties that might promote a hospitable habitat to support vegetation in such extreme environments.Summary: We added artificial root exudates to stimulate enzymatic function in two contaminated soils. Plant shoot mass, soil percent moisture, glomalin content, and organic matter content significantly increased due to the addition of artificial root exudates to the study soils. Microbially-mediated phosphatase activity was established in a barren, previously inactive, polluted soil.

Screening Of Phytochemicals Identified And Antioxidant Activity Of Aegiceras corniculatum Extract That Cultivates From The Mangrove Area Of Tarakan City

Aegiceras corniculatum is mangrove vegetation that is widely spread in the mangrove area in Karang Rejo, Tarakan City and it has the potential for the development of drugs from natural ingredients from tropical sea coasts. The purpose of this study was to determine the water content, bioactive compounds, and antioxidant activity of A. corniculatum. The methods used were the analysis of water content, analysis of bioactive compounds using the phytochemical method, and analysis of antioxidant activity using the DPPH method. This study showed the percentage of moisture or water content in the leaf and fruit extracts of A. corniculatum were 1.83% and 1.95%, respectively. The bioactive compounds detected in the leaf and fruit extracts came from flavonoids, alkaloids, tannins, phenol hydroquinone, and saponins. The antioxidant analysis showed that the fruit and leaf crude extracts had an antioxidant activity with IC50 values were 129.7 ppm and 365.8 ppm, respectively.

Soil Characterisation and Its Effect on Depth Accuracy Using Ground Penetrating Radar

Assessing depth of utility in different soil moisture conditions require good research. Moreover, different soil moisture conditions produce depths that are not the same as one another. The information of underground utility such as depth is very important to avoid damage towards utility during excavation process. Therefore, this study was conducted to assess the depth recorded by the (GPR) equipment in different soil condition in terms of soil moisture. The first objective of this study was to determine the soil moisture level for three different soil conditions. Next, this study evaluated the depth accuracy produced by the GPR equipment with the different soil moisture level such as dry, semi-dry and wet. Different soil moisture conditions were determined by the sampling of the three soil conditions. These samples were taken and tested using speedy soil moisture tester equipment that provided the percentage of soil moisture content. Next, the depth of utility was taken at the three soil moisture conditions and an assessment was made. The shape of hyperbolic on the radargram was generated from the equipment and was used to assess the accuracy of the depth. The information from this study is very useful to underground utility users which can help the development of the country in general. It also benefits the improvement of the preparation quality of underground utility mapping.

Effect of Storage Materials and Duration on Quality of Rice Seed

Storage loss of rice seed in terms of quality parameters is higher in Nepal due to lack of information about the effect of storage materials. Laboratory experiment was conducted to evaluate the effect of storage materials and storage period on quality parameters of rice seed (Oryza sativa L. cv., Bahuguni dhan-1). Rice seed was stored in seven storage materials (metal bin, plastic bin, super grain bag, PICS bag, plastic bag with jute sack, jute sack and earthen pot) in Completely Randomized Design with three replications at the Seed Laboratory of National Wheat Research Program, Bhairahawa, Rupandehi, Nepal from March to July, 2021. Seed moisture content and germination percentage were recorded before storage and after one, three and five months of storage. The population of two insect pests rice weevil and maize weevil was recorded after five months of storage. The result revealed that all the seed quality parameters under study were significantly influenced by storage materials. PICS bag followed by super grain bag was found to be superior in terms of seed moisture content, germination percentage and seed health throughout the storage period. Seed in the indigenous storage materials (earthen pot and jute sack) lost their quality significantly throughout the storage period. Future research strategies should focus on seed quality study under several indigenous storage materials found in Rupandehi district of Nepal.

Estimation of the moisture content, volatile matter, ash content, fixed carbon and calorific values of saw dust briquettes

“One way of making efficient use of existing resources is briquetting. Briquetting involves collecting combustible materials that are not usable due to lack of density, and compressing them into solid fuels of convenient shape that can be burnt like wood or charcoal”. “Biomass briquette is one of the proven ways of generating energy from waste”. “Fossil fuels, wood fuels and natural gas are the major sources for energy in Nigeria today”. “The excess use of these fuels will lead to serious environmental issues like global warming, air pollution and deforestation”. “This work is focused on estimating the heating values of sawdust briquettes to ascertain its suitability for domestic use and small-scale industrial cottage application”. “The results obtained shows that average percentage moisture content is 5.04%, average percentage volatile matter is 10.80%, average percentage ash content is 3.85%, average percentage fixed carbon is 80.95% and average percentage calorific value is 26918.02KCal/Kg. These results indicate that the briquettes made from sawdust have high heating value enough for domestic use and small-scale industrial cottage applications”.

Microbiological Assessment of Groundnut Paste Sold in Jimeta Markets, Yola, Adamawa State Nigeria

Groundnut paste is frequently associated with food-borne illness due to contamination traceable to food handlers, processing materials as well as environmental conditions and this therefore necessitated the microbiological quality examination of groundnut paste. The percentage occurrence of bacteria isolates and moisture content were determined using standard laboratory techniques. The percentage moisture content of the groundnut pastes was between the range of 0.8% and 4.8%. Total bacteria count fell between 1.8 ×1014 and 12.4 × 1014CFU/mL with organisms such as Proteus species (spp.), Pseudomonas spp., Bacillus spp., Salmonella spp., Klebsiella spp., Stapylococcus aureus, Escherichia coli, Shigella spp., Alcaligenes faecalis and Enterobacter spp. isolated. Total fungal count was between 2×107 and 4×107CFU/mL with identified organisms such as Aspergillus niger, Aspergillus flavus, Rhizopus spp. and Penicillium spp. Proteus spp. was the most prevalent with a percentage of 19.23 % while Escherichia coli, Alcaligenes faecalis and Enterobacter spp. showed the least prevalence of 3.85%. The results also show that fungi species spreads across all the samples with Aspergillus niger and Aspergillus flavus obtained in two of the samples, Rhizopus spp. in three other samples while Penicillum spp. were obtained in four samples. It is apparent from the result of this study that the groundnut paste examined were highly contaminated with microbial isolates sufficient enough to be a public health hazard in Jimeta markets and Adamawa State at large, therefore caution must be applied in its uses and consumption.

Physical and mechanical properties of lightweight concrete based on gypsum binders and peat vermiculite granules

Introduction. An analysis of the literature and experimental data on the resource provision of the construction market has shown that the development of new and effective materials with improved quality parameters is an urgent task, and in the long term will serve as an impetus for the development of the building materials market. Currently, the peat industry in Russia is experiencing a serious decline in the extraction of peat raw materials, the reserves of which are practically inexhaustible. One of the possible ways to develop this industry in the Tomsk region can be the organisation of the production of competitive structural, heat-insulating and heat-insulating materials using local raw materials, namely lowland peat and vermiculite, which will improve the economic prestige of the region, create new enterprises and jobs.Materials and methods. The studies using the methods and tests set out in national standards were carried out. The measurement of the obtained material density was carried out in accordance with GOST 17177-94. The determination of the samples strength in compression and in bending was carried out in accordance with GOST 23789-2018. The determination of the moisture content percentage of the samples was carried out in accordance with GOST 23789-2018.Results. The results of the research made it possible to determine the basic requirements for the designed composition of lightweight concrete based on gypsum binders and peat vermiculite granules. The relationship between the strength characteristics and density of lightweight concrete has been studied, it has been established that at average density values in the range of 530-850 kg/m3, the resulting material meets the basic technical requirements of heat-insulating lightweight concrete (GOST 25820-2014).Discussion and conclusions. In the work, experimental studies determined the rational ratio of the components of lightweight concrete based on gypsum binder and peat vermiculite granules, at which the maximum value of their strength is achieved at a minimum average density. Based on the data obtained, it was found that in order to achieve the necessary physical and mechanical properties of lightweight concretes based on gypsum binders, the optimal size of peat-vermiculite granules should be no more than 5 mm.

Quality Characterization of Different Parts of Broiler and Ligor Hybrid Chickens.

The quality characterization of different parts of male and female Ligor hybrid chickens was investigated and compared with those of commercial broiler. Genotypes, muscle types, and sex had effects on the composition, physicochemical, and textural properties of chicken samples. Ligor hybrid chicken contained higher percentages of protein, moisture, ash, and collagen content but lower fat content than those of commercial broiler (p < 0.05), except in the case of breast, where no significant difference in moisture and ash was observed (p ≥ 0.05). The pH in breast meat of both chickens was lower than that of thigh meat. The color (L*, a*, and b*) values of male and female chickens were not significantly different, except for the L* value of broiler chicken, which was higher in female chickens than in male chickens. Higher cooking loss and shear force were found in male Ligor hybrid chicken. A similar protein pattern was observed for the protein from the same muscle type, irrespective of sex and genotype tested. It was observed that Ligor hybrid chicken contained higher glutamic acid and aspartic acid than commercial broilers. Therefore, Ligor hybrid chicken is a promising new source of nutrition, which can be beneficial for consumers.

Pengaruh Perlakuan Filler Serat Kulit Buah Pinang Menggunakan Silane Coupling Agent terhadap Sifat Fisis dan Mekanis Papan Partikel

This study aims to examine the effectiveness of the addition of Silane Coupling Agent on physical properties (density, moisture content, thickness expansion, and water absorption) and flexural strength in the manufacture of areca nut peel fiber particle board with urea formaldehyde adhesive. The betel nut peel fiber was alkalized using NaOH for 2 hours, then mashed using a grinding machine until it passed a 50 mesh sieve. The betel nut skin fibers that have passed the sieve are then treated with a solution of Silane Coupling Agent. The concentration variations of the Silane Coupling Agent solution were 0%, 2%, 4%, 6% and 8%. The betel nut peel fiber that has been synthesized with a silane coupling agent solution is then mixed with urea formaldehyde resin in a ratio of 30/70 in weight percent. The particleboard compaction process uses a Hydraulic Cold Press compacting machine with a pressure of 5 bar and a holding time of 120 minutes. The results of this study indicate that the silane coupling agent treatment increases the bond between the matrix and filler as shown in the SEM test on particle boards with 8% silane coupling agent treatment. The results of the particleboard test on density, percentage of moisture content, percentage of thickness development have met the standard of SNI 03-2105-2006. The results of the water absorption test have met the ASTM D 570 standard. The results of the flexural strength test on the SCA 6% variation SNI 03-2105-2006 decorative particle board type 8 and the SCA 8% variation have met the SNI standard 03-2105-2006 structural particle board type 10.5.This study aims to examine the effectiveness of the addition of Silane Coupling Agent on physical properties (density, moisture content, thickness expansion, and water absorption) and flexural strength in the manufacture of areca nut peel fiber particle board with urea formaldehyde adhesive. The betel nut peel fiber was alkalized using NaOH for 2 hours, then mashed using a grinding machine until it passed a 50 mesh sieve. The betel nut skin fibers that have passed the sieve are then treated with a solution of Silane Coupling Agent. The concentration variations of the Silane Coupling Agent solution were 0%, 2%, 4%, 6% and 8%. The betel nut peel fiber that has been synthesized with a silane coupling agent solution is then mixed with urea formaldehyde resin in a ratio of 30/70 in weight percent. The particleboard compaction process uses a Hydraulic Cold Press compacting machine with a pressure of 5 bar and a holding time of 120 minutes. The results of this study indicate that the silane coupling agent treatment increases the bond between the matrix and filler as shown in the SEM test on particle boards with 8% silane coupling agent treatment. The results of the particleboard test on density, percentage of moisture content, percentage of thickness development have met the standard of SNI 03-2105-2006. The results of the water absorption test have met the ASTM D 570 standard. The results of the flexural strength test on the SCA 6% variation SNI 03-2105-2006 decorative particle board type 8 and the SCA 8% variation have met the SNI standard 03-2105-2006 structural particle board type 10.5.

Comparing the Soil Conservation Service model with new machine learning algorithms for predicting cumulative infiltration in semi-arid regions

Water infiltration into soil is an important process in hydrologic cycle; however, its measurement is difficult, time-consuming and costly. Empirical and physical models have been developed to predict cumulative infiltration (CI), but are often inaccurate. In this study, several novel standalone machine learning algorithms (M5Prime (M5P), decision stump (DS), and sequential minimal optimization (SMO)) and hybrid algorithms based on additive regression (AR) ( i.e ., AR-M5P, AR-DS, and AR-SMO) and weighted instance handler wrapper (WIHW) ( i.e ., WIHW-M5P, WIHW-DS, and WIHW-SMO) were developed for CI prediction. The Soil Conservation Service (SCS) model developed by the United States Department of Agriculture (USDA), one of the most popular empirical models to predict CI, was considered as a benchmark. Overall, 154 measurements of CI (explanatory/input variables) were taken from 16 sites in a semi-arid region of Iran (Illam and Lorestan provinces). Six input variable combinations were considered based on Pearson correlations between candidate model inputs (time of measuring and soil bulk density, moisture content, and sand, clay, and silt percentages) and CI. The dataset was divided into two subgroups at random: 70% of the data were used for model building (training dataset) and the remaining 30% were used for model validation (testing dataset). The various models were evaluated using different graphical approaches (bar charts, scatter plots, violin plots, and Taylor diagrams) and quantitative measures (root mean square error (RMSE), mean absolute error (MAE), Nash-Sutcliffe efficiency (NSE), and percent bias (PBIAS)). Time of measuring had the highest correlation with CI in the study area. The best input combinations were different for different algorithms. The results showed that all hybrid algorithms enhanced the CI prediction accuracy compared to the standalone models. The AR-M5P model provided the most accurate CI predictions (RMSE = 0.75 cm, MAE = 0.59 cm, NSE = 0.98), while the SCS model had the lowest performance (RMSE = 4.77 cm, MAE = 2.64 cm, NSE = 0.23). The differences in RMSE between the best model (AR-M5P) and the second-best (WIHW-M5P) and worst (SCS) were 40% and 84%, respectively.

Analysis Effect of Nano Chitosan Coating on The Quality of Shallot Bulbs (Allium ascalonicum L. var. Bauji)

Shallots are bulb-shaped commodities that are difficult to maintain in new conditions because they are easily damaged. An effective effort to prevent deterioration of food quality during storage is by coating it using nano chitosan. The effectiveness of nano chitosan is influenced by particle size which related to the ratio of chitosan and STPP (sodium tripolyphosphate). This study aimed to determine the effect of nano chitosan coating with the addition of different ratios of chitosan and STPP and the appropriate ratio of chitosan and STPP on nano chitosan as a coating to maintain the quality of shallot bulbs (Allium ascalonicum L. var. Bauji). This study used a completely randomized design (CRD) method with four treatments and five replications. The treatments of this research were P0= Control, PI= Nano chitosan ratio of chitosan: STPP 1:3, P2= Nano chitosan ratio of chitosan:STPP 1:4, and P3= Nano chitosan ratio of chitosan:STPP 1:5. The variables of this study were the percentage of damage, the percentage of diameter shrinkage, weight loss, color, hardness, and moisture content. Data were analyzed using the ANOVA test and continued with the DMRT test. The application of nano chitosan coating on shallot bulbs could reduce damage, shrinkage of tuber diameter, weight loss, color, hardness, and decrease in water content better than the control treatment. The best results were shown by treatment P3 (1:5) with a percentage of damage of 8%, diameter shrinkage of 20.20%, weight loss of 18.40%, total color change of 54.45, hardness of 226.23 N, and a decrease in water content of 4.65% at the final water content of 79.09%.

The Economic Impact of a Renewable Biofuels/Energy Industry Supply Chain Using the Renewable Energy Economic Analysis Layers Modeling System

The University of Tennessee’s (UT) Department of Agricultural and Resource Economics models supply chains for both liquid and electricity generating technologies currently in use and/or forthcoming for the bio/renewable energy industry using the input–output model IMPLAN®. The approach for ethanol, biodiesel, and other liquid fuels includes the establishment and production of the feedstock, transportation of the feedstock to the plant gate, and the one-time investment as well as annual operating of the facility that converts the feedstock to a biofuel. This modeling approach may also include the preprocessing and storage of feedstocks at depots. Labor/salary requirements and renewable identification number (RIN) values and credits attributable to the conversion facility, along with land-use changes for growing the feedstock are also included in the supply chain analyses. The investment and annual operating of renewable energy technologies for electricity generation for wind, solar, and digesters are modeled as well. Recent modeling emphasis has centered on the supply chain for liquid fuels using the Bureau of Economic Analysis’s 179 economic trading areas as modeling regions. These various data layers necessary to estimate the economic impact are contained in UT’s renewable energy economic analysis layers (REEAL) modeling system. This analysis provides an example scenario to demonstrate REEAL’s modeling capabilities. The conversion technology modeled is a gasification Fischer–Tropsch biorefinery with feedstock input of 495,000 metric tons per year of forest residue transported to a logging road that is less than one mile in distance. The biorefinery is expected to produce sustainable aviation fuel (SAF), diesel, and naphtha. An estimated one million tons of forest residue are required at fifty percent moisture content. Based on a technical economic assessment (TEA) developed by the Aviation Sustainability Center (ASCENT) and the quantity of hardwood residues available in the Central Appalachian region, three biorefineries could be sited each utilizing 495,000 dry metric tons per year. Each biorefinery could produce 47.5 million liters of SAF, 40.3 million liters of diesel, and 23.6 million liters of naphtha. Annual gross revenues for fuel required for the biorefineries to break even are estimated at $193.7 million per biorefinery. Break-even plant gate fuel prices when assuming RINs and 12.2 percent return on investment are $1.12 per liter for SAF, $1.15 per liter for diesel, and $0.97 per liter for naphtha. Based on IMPLAN, an input–output model, and an investment of $1.7 billion, the estimated economic annual impact to the Central Appalachian region if the three biorefineries are sited is over a half a billion dollars. Leakages occur as investment dollars leaving the region based on the regions local purchase coefficients (i.e., LPPs), which totals $500 million. This results in an estimated $2.67 billion in economic activity with a multiplier of 1.7, or for every million dollars spent, an additional $0.7 million in economic activity is generated in the regional economy. Gross regional product is estimated at $1.28 billion and employment of nearly 1,200 jobs are created during the construction period of the biorefineries, which results in $700 million in labor income with multiplier effects. Economic activity for the feedstock operations (harvesting and chipping) is estimated at slightly more than $16.8 million resulting in an additional $30 million in the economic impact. The stumpage and additional profit occurring from the harvest of the forest residues result in $40 million directly into the pockets of the resource and logging operation owners. Their subsequent expenditures resulted in a total economic activity increase of $71.4 million. These operations result in creating an estimated 103 direct jobs for a total of 195 with multiplier effects. Direct feedstock transportation expenditures of more than $36.7 million provide an estimated increase in economic activity of almost $68 million accounting for the multiplier effects.

Biogas production using poultry wastes, yam and plantain peels

Current global warming trends are primarily a result of the current energy reliance on fossil fuels and necessitate the provision of alternative sources of energy. Biofuels are one of the many alternatives to Hydrocarbon fuels. This research evaluates the potential of biogas production using poultry wastes, yam, and plantain peels in a ratio of 2:1:1. The organic waste materials were crushed using a sterile mortar and pestle. It was weighed and mixed with distilled water in a sterile bowl and loaded in a bioreactor for 45 days. The proximate analysis was carried out to determine the nutrient composition of the samples using standard procedures. Microbiological analysis was carried out using both general- purpose and differential media before and after loading the samples in the bioreactor. The pH and the temperature were monitored as well. A flame meter was used to compare the quality of the gas produced with that of cooking gas. The percentage moisture content obtained was 21.31, 28.71 and 23.17, % crude protein (6.17, 5.98 and 7.17), % ash content (7.9, 4.37, 12.13), % fat content (2.13, 1.14, 7.24), %crude fiber (19.94, 14.36, 36.89), % carbohydrate (42.53, 39.06 and 13.12) and the calories value of (213.09, 196.43 and 146.36) for plantain peels, yam peels and poultry waste respectively. Three fungal isolates and nine bacterial isolates were obtained. Produced biogas constituted of 310, 1352, and 2264 ppm of Liquified Petroleum Gas, Carbon (II) Oxide, and Smoke respectively. The biogas was observed to be highly flammable and burnt with a bluish flame.

Comparative phytochemicals screening and estimation of constituents present in the leaves of Decalepis species through HPLC

Background and objectivesThe variation in the active phytoconstituents in different plants causes changes in their biological properties. The present study was aimed with the comparative phytochemicals and estimation of the constituent present in the leaves of Decalepis species using high performance liquid chromatography (HPLC). Materials and MethodsThe leaves of Decalepis hemiltonii Wight & Arn. Decalepis arayalpathra(J. Joseph and V. Chandras.) Venter. and Decalepis nervosa(Wight &Arn.) Venter.were selected and methanol solvent was used for the preparation of the extracts. Various proximate analysis viz. moisture content, ash values, crude fibers, extractive values were estimated. Thereafter, series of basic chemical tests for the methanol leaves extracts followed by total phenolics, and total flavonoids content were also carried out. Furthermore, TLC chromatogram and RP-HPLC study was carried out for all the plant extracts to find out the presence of phenolic compounds and compared the estimated amount present in all the leaves extracts. ResultsThe outcome of the study revealed that all the three species varied with the yield and the phytochemical screening showed varied concentration of alkaloids, glycosides, flavonoids, proteins, steroids, phenols, and tannins. Among the three species Decalepis hemiltonii(DH) showed presence of higher percentage of moisture (8.6%), crude fibers (8.32%) and total ash content (4.95%) than others. Further, presence of high concentration of phytochemicals was showed by Decalepis arayalpathra (DA) and the higher yield in methanol solvent than other two species. The same plant sample showed presence of higher amount of gallic acid (0.86 mg/100 g) than other two species. Total alkaloids, total phenolic and total flavonoids were higher in DA leaves flowed by Decalepis nervosa (DN) and DH leaves samples. InterpretationOverall the results indicated that DA leaves extracts was better in terms of yield, presence of phytoconstituents, presence of total alkaloids, total flavonoids, and total phenolics and presence of gallic acid followed by DN and DH leaves.

Development of a forced convection electric fish drying machine

A forced convection electric fish dryer was developed in this study to provide an efficient means of drying fish in urban and rural areas and serve as a substitute for the largely inefficient local means of drying fish. The machine was designed to accommodate 126 kg of fish distributed accordingly within the drying chamber. Six flat electric coils of 3 kW capacity each and a fan blower were provided to induce a saturating forced convective current within the drying chamber. The machine was evaluated at a drying temperature of 60oC with a total of 126 kg catfish, 21 kg on each tray. The result showed that percentage moisture contents of 81.8%, 72.7%, 62.7%, 54.1%, 47.7%, and 40.9 % were evaporated from the fish on the sixth to the first tray respectively in one hour. The mean percentage of moisture evaporated from all the trays was 60 %.

Experimental and computational study of a flighted rotary drum cross-sectional characteristics

The current work involves experimental and computational study of rotary drum cross-sectional characteristics such as: kinetic angle of repose (AoR), flight holdup, flight geometry and flight discharge energy. Experiments with two spherical and three non-spherical particulate materials with sizes between 70 μm and 2 mm were performed in a home-made rotary drum to measure the kinetic angle of repose as a function of flight angular position and drum rotational speed. As a result, an empirical model was proposed to predict the kinetic AoR as a function of the Archimedes number (Ar), Froude number (Fr), and flight angular position. The kinetic AoR predicted by the model is fairly correlated with the experimental findings, with an error of ±8%. The effect of moisture was also examined for a single case of material type and percentage of moisture content, and the results indicated that the same model for dry material can be applied to moist material. In addition, a simple computational algorithm was introduced to predict the flight holdup for any angular position of the flight. Validation using experimental data from the literature demonstrated the soundness of the model. Furthermore, a discharge energy characteristic was introduced, and a parametric study showed that this characteristic can be used as a new key parameter for optimization purposes.

Evaluation of Selected Physical Properties of Blighia sapida K. Koenig Wood

Blighia sapida, a Lesser-Used Species is being processed into sawn timber to meet the demand for wood. The knowledge of its wood quality would enhance its effective utilization. However, there is little information known on the physical properties of this species that could enhance its acceptability and optimum utilization. This, therefore, necessitate the need to investigate the physical properties of this wood species.&#x0D; Three standing trees of B. sapida were purposively felled for this study. Billets of 500 mm were obtained from the wood disc at the base, middle, and top of the tree. Each wood disc was partitioned into three; innerwood, middlewood, and outerwood following specified international standards for the physical properties test (wood colour, proportion of sapwood and heartwood, bark thickness, density, moisture content, and volumetric shrinkage).&#x0D; B. sapida wood density with a mean value of 709.78±8.88 kg/m3, ranged from (571.59±13.45 to 854.81±7.08 kg/m3. Moisture content percentage of average value 70.62±1.23%, ranged from 53.84±1.40 to 89.00±2.75%. Volumetric shrinkage of average value 15.24±0.25%, range from 13.38±0.66 to 16.89±0.83%. The range of B. sapida wood density value of the study falls within the range that could be categorized as medium density wood of medium construction strength properties. The 1:1.5% tangential–radial shrinkage observed in this study was low, an indicator of a low risk of deformation while seasoning the wood, as the ratios of tangential-radial shrinkage that is high are those over 2.2%.

Experimental Study on Coal and Gas Outburst Risk in Strong Outburst Coal Under Different Moisture Content

Coal and gas outburst is an extremely serious dynamic phenomenon involving the comprehensive action of many factors, and remains a major disaster that needs to be solved in coal mine production. Considering the significant influence of moisture content on coal and gas outburst, it is necessary to carry out experimental research on coal and gas outburst under different moisture content conditions. The coal of the serious outburst coal seam in the Luling coal mine, which has had several coal and gas outburst accidents, was selected as the experimental sample. Firstly, the gas desorption law and outburst index characteristics of coal under different moisture content were studied, and the influence of moisture content on gas outburst parameters of coal was obtained. Then, the simulation tests of coal and gas outburst under different moisture content were carried out by using a triaxial coal and gas outburst simulation test system. Based on the above experimental research, the influence of moisture on coal and gas outburst was summarized, and the energy calculation and prevention countermeasures of coal and gas outburst under different moisture content conditions were carried out. With the increase of moisture content, the adsorption constant a, the initial velocity of gas diffusion Δp, and the gas desorption index of drill cuttings K1/Δh2 decrease, but the Protodyakonov coefficient f increases, all of which have an exponential relation to moisture content. Meanwhile, with the increase of moisture content, the threshold of coal and gas outburst pressure increases, and the intensity and energy of outburst decrease. At 0.45 MPa pressure, the outburst of 1.47% moisture content is the most serious, the outburst of 5% moisture content is weakened, while the outburst of 10% moisture content is not triggered. Five percent moisture content can be used as a critical index of hydraulic measures to prevent coal and gas outburst in No. 8 coal seam of the Luling coal mine. This research can provide new insights into the theoretical study of coal and gas outburst in serious outburst coal seams and the control of coal and gas outburst by hydraulic measures.

SEASONAL VARIATIONS OF SATURATED HYDRAULIC CONDUCTIVITY, PERCENTAGE POROSITY AND ORGANIC MATTER CONTENT OF AN ULTISOL IN IMO STATE, NIGERIA

The wet and dry seasons in tropical soils not only differ markedly in precipitation, moisture content and irradiation but also can potentially affect some of the key characteristics that define different soil types. The seasonal effects on saturated hydraulic conductivity, percentage porosity and organic matter status was conducted in an Ultisol in Imo state Nigeria in 2016 and 2017. Four different land uses was used for the study. Samples were collected in the rainy and dry seasons of 2016 and 2017 through the sampling of the horizons of the land uses through the different profile pits dug in the land uses. Collected samples were prepared using standard procedures. Results indicate obvious variations in the soils saturated hydraulic conductivity in both rainy and dry seasons of 2016 and 2017 with the first dry season having the highest percentage of total porosity. Similarly the dry season had the lowest moisture content with the second dry season having the highest percentage moisture content of 17.2. All the parameters studied showed obvious variations in both seasons. Thus having a good knowledge of the seasonal variations in soil hydraulic parameters will unarguably preform land users on the potential dangers that may disrupt the food supply chain. Improving the organic matter content of the soil through mulching and fallowing will reduce the seasonal variations that are usually encountered by land users.

Nitrogen application affects maize grain filling by regulating grain water relations

Grain water relations play an important role in grain filling in maize. The study aimed to gain a clear understanding of the changes in grain dry weight and water relations in maize grains by using hybrids with contrasting nitrogen efficiencies under differing nitrogen levels. The objectives were: 1) to understand the changes in dry matter and percent moisture content (MC) during grain development in response to different nitrogen application rates and 2) to determine whether nitrogen application affects grain filling by regulating grain water relations. Two maize hybrids, high N-efficient Zhenghong 311 (ZH311) and low N-efficient Xianyu 508 (XY508), were grown in the field under four levels of N fertilizer: 0, 150, 300, and 450 kg N ha–1 during three growing seasons. Dry weight, percent MC and water content (WC) of basal–middle and apical grains were investigated. The difference in the maximum WC and filling duration of basal–middle and apical grains in maize ears resulted in a significant difference in final grain weight. Grain position markedly influenced grain drying down; specifically, the drying down rate of apical grains was faster than that of basal–middle grains. Genotype and grain position both influenced the impact of nitrogen application rate on grain filling and drying down. Nitrogen rate determined the maximum grain WC and percent MC loss rate in the middle and the late grain-filling stages, thus affecting final grain weight. The use of high N-efficient hybrids, combined with the reduction of nitrogen application rate, can coordinate basal–middle and apical grain drying down to ensure yield. This management strategy could lead to a win–win situation in which the maximum maize yield, efficient mechanical harvest and environmental safety are all achieved.