Potassium Sulfate Research Articles

Boosting the “Solid–Liquid–Solid” Conversion Reaction via Bifunctional Carbonate‐Based Electrolyte for Ultra‐long‐life Potassium–Sulfur Batteries

AbstractPotassium–sulfur (K−S) batteries have attracted wide attention owing to their high theoretical energy density and low cost. However, the intractable shuttle effect of K polysulfides results in poor cyclability of K−S batteries, which severely limits their practical application. Herein, a bifunctional concentrated electrolyte (3 mol L−1 potassium bis(trifluoromethanesulfonyl)imide in ethylene carbonate (EC)) with high ionic conductivity and low viscosity is developed to regulate the dissolution behavior of polysulfides and induce uniform K deposition. The organic groups in the cathode electrolyte interphase layer derived from EC can effectively block the polysulfide shuttle and realize a “solid–liquid–solid” reaction mechanism. The KF‐riched solid‐electrolyte interphase inhibits K dendrite growth during cycling. As a result, the achieved K−S batteries display a high reversible capacity of 654 mAh g−1 at 0.5 A g−1 after 800 cycles and a long lifespan over 2000 cycles at 1 A g−1.

Effect of Exogenous Substance K2SO4 on the Nutritional Quality of Broccoli and Its Metabolic Regulation Mechanism

The impact of exogenous sulfate components on the nutritional quality of vegetables has been well documented. In this study, we examined the effects of adding K2SO4 to broccoli on its nutritional quality, active components, and the genes involved in glucosinolate synthesis. Different concentrations of exogenous K2SO4 of 25, 75, and 150 g·m−2 were applied to the “Naihan Youxiu” broccoli cultivar, while the control treatment received no potassium sulfate. Our primary objective was to gain insights into strategies for enhancing broccoli’s nutritional and active components. The results showed that broccoli’s vitamin C content in each treatment was lower than that in the control treatment. The contents of soluble protein, soluble sugar, polyphenols, and total flavonoids in the treatment of 150 g·m−2 K2SO4 were the highest. They increased by 23.51%, 87.49%, 146.00%, and 22.73% more than the control, respectively. MDA was significantly inhibited after the 75 g·m−2 treatment, whereas SOD had the highest activity under the 75 g·m−2 treatment. Therefore, the 150 g·m−2 treatment was beneficial in improving the nutritional quality and antioxidant capacity of broccoli. The contents of PRO, SIN, NAP, GBC, 4ME, NEO, total indole glucosinolates, and total glucosinolates reached the peak at the 150 g·m−2 K2SO4 treatment, RAA and total aliphatic glucosinolates reached the peak at the 75 g·m−2 K2SO4 treatment, and ERU and 4OH reached the highest at the 25 g·m−2 K2SO4 treatment. The sulforaphane content was the highest in the 150 g·m−2 treatment, and myrosinase activity was the highest in the 75 g·m−2 treatment. It can be seen that the 150 g·m−2 treatment significantly increased the content of glucosinolates, total indole glucosinolates, total glucosinolates, and sulforaphane in broccoli. CYP79B2, CYP83B1, CYP83A1, AOP2, UGT74B1, and MYB34 were significantly up-regulated under 150 g·m−2 K2SO4 treatment and reached the peak value. CYP79F1, CYP81F4, and MAM1 showed significant inhibitory effects when treated with 150 g·m−2 of K2SO4. The expression levels of BCAT4, CYP81F1, ST5a, ST5c, and SUR1 were down-regulated under the 150 g·m−2 K2SO4 treatment, but not significantly. In summary, the K2SO4 150 g·m−2 treatment had the best effect on nutritional quality, antioxidant activity, the content of glucosinolates, total glucosinolates, sulforaphane, and expression of CYP79B2, CYP83B1, CYP83A1, FMO2, UGT74B1, AOP2, and MYB34 genes.

Process of soil salinization as a function of watermelon mineral fertilization

The watermelon (Citrullus lanatus L.) is a cucurbitaceous plant of great social and economic importance in Brazil, especially in the north-eastern region. However, anthropic actions through the practice of irrigation, fertigation and fertilization in an inadequate way, have potentiated the salinization of the soil becoming this one of the main factors that limit the production and the quality of the fruits. In this work, the effects of the application of mineral fertilization on the salinization of soil cultivated with watermelon were evaluated. The experiment was performed in the city of Petrolina-PE, with four repetitions, using five treatments: (T0) no fertilization, (T1) NPK fertilization, (T2) average dose of NPK practiced by producers, (T3) maximum dose of NPK from producers having potassium chloride as a source of potassium and (T4) maximum dose of NPK from producers having potassium sulfate as a source of potassium, at two different depths: 0.00 - 0.20 m and 0.20 - 0.60 m. The soil chemical attributes analyzed were pH, electrical conductivity (EC), organic matter, phosphorus, potassium, sodium, calcium and magnesium. The increase in the continuous application of mineral fertilizers raised the electrical conductivity values of the soil to levels prejudicial to the crop.

Effect of water quality, mineral fertilizer levels and methods of adding seaweed extracts on reducing salt stress, growth and yield of cauliflower.

A field experiment was conducted at one of the research stations of the College of Agricultural Engineering Sciences / University of Baghdad in Al-Jadiriyah region for the autumn season 2021-2022, located within 33.27 north latitude and 44.39 east longitude, in Clay soil with a Split Plot Design design and with three replicates to study the effect of Irrigation water quality, mineral fertilizer and methods of adding marine extracts to reduce salt stress and cauliflower growth and yield. The experiment included three factors: irrigation with two types of water, regular irrigation water (tap water) with an electrical conductivity of 0.9 dSm-1, and the second is saline water (wastewater) with an electrical conductivity of 4.8 dSm-1 and two levels of mineral fertilizer 50% and 100% of Fertilizer Recommendation and Extracts with six different levels of supplementation (S0, S1, S2, S3, S4 and S5). Cauliflower seedlings, Prassica oleracea, and cultivar Megha were transferred to the field on 9-15-2021. Nitrogen was added by 300 kg. N ha-1 in urea (46% N) and phosphate in 100 kg. P ha-1as triple superphosphate (20% p)and potassium by 150 kg. K ha-1 is in the form of potassium sulfate (42% K). Soil samples were taken over the length of the experiment and periods (30, 45, 60 and 75 days) to estimate the electrical conductivity in the soil. At the end of the season, the yield of cauliflower was estimated. The results showed the significant effect of irrigation water quality, mineral fertilizer, and methods of adding marine extracts in reducing the electrical conductivity of the soil and increasing the cauliflower yield and treatment (W1M2S5) achieved the highest significant increase in cauliflower yield, with an increased average of 47.97%, followed by treatment (W2M2S5), with an increased average of 42.63%. Keywords: water quality, seaweed extracts

Effect of Sulphate Attack on Self Compacting Concrete

Many current structures are characterized by the complexity of architecture (various shapes and bends) and a high concentration of reinforcement which often makes it difficult to use concrete with conventional plasticity. Recent researches have been conducted in order to adopt concrete to these structures. The resulting concrete formulations are characterized by better workability, while remaining stable with mechanical properties and durability. This new type of concrete can fit in place under the influence of gravity, hence the term self compacting concrete “SCC”.
 The external attack of sulphate salts is considered as one of the major problems affecting concrete durability. Sulphates are highly soluble salts in the form of sodium sulphate, calcium sulphate, potassium sulphate, and magnesium sulphate. Sulphate attack is a process in which sulphates react with various phases of hydrated cement paste leading to deterioration of the concrete matrix through spalling, softening, and mass loss, which may lead to expansion and loose strength and elasticity. It is recognized as a complex process due to the effect of The aim of this study to demonstrate the change in strength in SCC when the cement is replaced with lime powder and to determine the sulphate attack on the self compacting concrete.
 Compressive strength characteristics for 7days and 28days of the self compacting concrete are determined in which cement is partially replaced with lime powder (0%, 10%, 20%, 30%, 40%) and cured in the sodium sulphate solution.
 To attain the planned objectives of the present investigation, M20 grade self compacting concrete is taken and values of cement replaced with limestone at the percentages of 0%,10%,20%,30% were considered. The total of 48 cubes,48 cylinders were casted.24 cubes and 24 cylinders are cured in normal water and 24 cubes and 24 cylinders are cured in sodium sulphate solution. and determined the compressive strength and split tensile strength values. The developments of compressive and tensile strengths of self compacting concrete at the age of 7and 28 days are investigated. Under the influence of external sulphate attack. The parameters comparing the SCC with normal concrete are increased at the 20% of lime powder replacement after that the parameters decreases gradually.

Micro-nano bubble water with potassium fertigation improves strawberry yield and quality by changing soil bacterial community

Aerated drip irrigation can increase the soil oxygen content and improve the utilization efficiency of fertilizer. However, limited information is available on how soluble potassium fertilizer with different aeration levels affects plant yield and quality. Specifically, the underlying mechanism associated with microbial community level has not been reported so far. In this study, a micro-nano bubble water (MNBW) drip irrigation experiment was conducted in a strawberry plantation greenhouse, with three ratios of MNBW and two potassium application amounts and a control treatment (without MNBW). The results showed that compared with the CK (no aeration, 100% traditional potassium fertilizer application, 144 kg hm−2 of potassium sulfate), MNBW irrigation improved the soil oxygen content and changed the structure and functionality of the soil microbial community in the strawberry rhizosphere. The bacterial diversity was reduced, and the microbial co-occurrence patterns were altered. The soil respiration intensity increased by 1.32%–14.22%. The soil temperature increased, and the decomposition of organic matter was enhanced. It was indicated that the increase of soil oxygen had a positive impact on soil fertility, strawberry yield, and quality under the condition of reducing potassium application. The yield and quality of strawberries in MNBW treatments were significantly higher than those treated with CK (p < 0.05), but the carbon dioxide emissions significantly increased. High potassium fertilizer application amount and MNBW ratio did not mean high yield and quality of strawberries. Thus, O20K70 (20% of irrigation water with micro-nano bubbles, 70% of traditional drip irrigation potassium fertilizer level, 101 kg hm−2 of potassium sulfate) and O60K70 (60% of irrigation water with micro-nano bubbles, 70% of traditional drip irrigation potassium fertilizer level, 101 kg hm−2 of potassium sulfate) could be chosen for strawberry plantations with MNBW.

Effects of chemical fertilizer reduction and organic fertilizer substitution on yield and quality of Saposhnikovia divaricata

To explore the suitable fertilizing pattern for Saposhnikovia divaricata in the genuine producing area, a field trial was carried out to investigate the changes in the yield and quality of medicinal materials and soil in different fertilization patterns, such as organic fertilizer substitution(organic fertilizer+NPK fertilizer) and chemical fertilizer reduction(organic fertilizer+NPK fertilizer decrement and organic fertilizer+NPK fertilizer decrement+soil conditioner). The comprehensive analysis of all treatments was based on the medicine quality evaluation data set and soil quality evaluation data set, respectively, by CRITIC weight method. The results showed that(1) the yield of S. divaricate increased by 4.93%-12.67% under the organic fertilizer substitution mode, and the yield increased by 44.43% under the treatment of chemical fertilizer reduction YHT15, which was higher than that of the organic fertilizer substitution mode.(2) The quality of S. divaricate under the two fertilization modes was superior to the standard in the Chinese Pharmacopoeia, and the application of biochar was helpful to improve the quality of S. divaricate quality, with an increase of 82.83%-181.54%. CRITIC method analysis showed that fertilization treatments with high comprehensive scores were YHT15, YH30, and YH15.(3) Soil quality under the two fertilization modes was higher than that under the control. The fertilization treatments with higher comprehensive scores of soil quality were YHT15, YHT30, and YHT. The fertilization mode of adding biochar as soil conditioner, applying an appropriate amount of organic fertilizer, and reducing part of chemical fertilizer is the appropriate way to develop ecological plantation of S. divaricata in the Baicheng area in the western Jilin province. The specific fertilization mode is as follows. The basic fertilizer was 361 kg·hm~(-2) superphosphate+110 kg·hm~(-2) potassium sulfate+82 kg·hm~(-2) organic fertilizer+10 000 kg·hm~(-2) rice husk biochar, and urea was applied as top fertilizer three times, 29, 29, and 20 kg·hm~(-2), respectively.

Stimulating growth, root quality, and yield of carrots cultivated under full and limited irrigation levels by humic and potassium applications

Water stress poses a significant challenge for carrot cultivation, leading to decreased yield and inefficient water use efficiency. Therefore, it is crucial to provide plants with suitable supplements that enhance their stress resistance. In this study, we investigated the effectiveness of humic and potassium applications on carrot growth, yield characteristics, root quality, and water use efficiency under varying irrigation levels. A split-split plot experiment was conducted, with two levels of gross water requirements (GWR) (100% and 80%) assigned to the main plots. The subplots were treated with humic acid through foliar application (Hsp) or soil drenching (Hgd). The sub-subplots were further divided to assess the impact of foliar potassium sources (potassium humate, Kh) and mineral applications (potassium sulfate, K2SO4). The results revealed a substantial reduction in carrot yield under limited irrigation, reaching about 32.2% lower than under GWR100%. Therefore, under limited irrigation conditions, the combined application of Hgd and K2SO4 resulted in a significant yield increase of 78.9% compared to the control under GWR80%. Conversely, under GWR100%, the highest average yield was achieved by applying either Hsp and Kh or Hsp and K2SO4, resulting in yields of 35,833 kg ha−1 and 40,183 kg ha−1, respectively. However, the combination of Hgd and Kh negatively affected the yield under both GWR100% and GWR80%. Nonetheless, applying Kh in combination with Hgd under GWR80% led to improved nitrogen, phosphorus, potassium, potassium/sodium ratio, and total sugar concentrations, while reducing sodium content in carrot roots. Based on this study, it is recommended to adopt GWR80% and treat plants with a combination of Hgd and foliar K2SO4. This approach can help plants overcome the negative effects of water stress, improve yield and root quality, and achieve optimal water use efficiency.

The Features of Potassium Dynamics in 'Soil-Plant' System of Sour Cherry Orchard.

This research aimed to study interannual and seasonal dynamics of different potassium compounds in orchard soil and the potassium status of sour cherry trees affected by the application of nitrogen and potash fertilizers. Afield experiment was started in 2017 at an orchard located in the forest-steppe zone of the Central Russian upland. Urea and potassium sulfate were applied to the soil once a year in early spring with rates from N30K40 to N120K160 kg/ha. The content of exchangeable and water-soluble potassium compounds was determined in soil samples five times throughout the growing season from May to September 2018-2020. The content of non-exchangeable potassium was determined twice, in 2017 and 2020. The interannual and seasonal dynamics of plant-available potash in unfertilized soil depended on the weather patterns and the uptake of potassium by trees. In the unfertilized plots, the first signs of potassium nutrition insufficiency appeared, such as low leaf and fruit potassium status and a decrease in the non-exchangeable potassium reserves in the20-40 cm soil layer. The annual fertilization led to the gradual accumulation of exchangeable potassium in the root zone. The accumulation was accelerated with increasing rates. When the exchangeable potassium level in the topsoil reached 200 mg/kg, the intensification of both the seasonal fluctuations in potash content and the potash leaching into the depths of the soil occurred in all treatments. In the conditions of our experiment, one-time treatments with superfluous potassium rates (over 80 kg/ha) did not provide an enlarged stock of plant-available potash in the soil but caused unreasonable losses of it due to leaching. An increase in fertilizer rates was not essential for normal metabolic processes and did not manifest itself as an increase in potassium content in leaves and fruits or as an increase in yield.

Effect of Potassium Doses on Agricultural Characteristics of Camelina Sown in Winter and Summer Season

This research carried out in Konya ecology, Arslanbey camelina [Camelina sativa (L.) Crantz] genotype which was planted in 2 different times as winter and summer, in the vegetation period of 2020, was determined at 6 different doses (0 kg da-1, 10 kg da-1, 15 kg da-1, 20 kg da-1, 25 kg da-1, 30 kg da-1) potassium sulphate fertilizer was applied to the soil and its effects on some agricultural properties were determined. Field trials of the study were established according to the Random Blocks trial design with 3 replications. As the results of the research in summer plantings, plant height 50.23-54.01 cm, number of branches per plant 5.60-8.80, number of capsules per plant 30.87-58.80, number of seeds per capsule 14.10-17.60, first capsule height 39.55-45.28 cm, seed yield per plant 0.28-1.27 grams, the number of seeds per plant 252.53-1166.13, thousand grain weight 0.78-1.12 grams, grain yield 63.76-77.75 kg da-1, oil rate 22.54%-29.66%, oil yield between 14.05-22.25 kg da-1. Additionally, the values obtained as a result of the winter planting of camelina; plant height 52.04-57.74 cm, number of branches per plant 8.33-11.70, number of capsules per plant 199.80-274.67, number of seeds in capsule 11.50-13.23, height of first capsule 41.01-47.17 cm, grain yield 1.24-1.65 grams per plant, number of seeds per plant 1754.43-2424.00 pieces, thousand grain weight 0.69-0.85 grams, grain yield 80.65-125.93 kg da-1, oil rate 14.47-18.77%, oil yield 11.97-19.74 kg da-1. It can be said that it is essential to carry out long-term different agronomic studies in different locations related to camelina, an important and alternative oil plant.

Efficacy of aluminum potassium sulfate against Staphylococcus species in wound infections compared to meropenem and amoxyclav

Efficacy of aluminum potassium sulfate against Staphylococcus species in wound infections compared to meropenem and amoxyclav

Early metakaolin reactions in pozzolanic R3-test: calorimetry baseline correction of initial temperature jump due to ex-situ mixing

The increasing concerns regarding global warming and the scarcity of raw materials in the construction industry have led to a growing need for alternative low-carbon binders to partially replace ordinary Portland cement. To assess the suitability of pozzolans as supplementary cementitious materials (SCMs), the R3-test has been introduced and successfully validated for a wide range of materials. This test provides an opportunity to analyze the reactivity classification and study the reaction mechanisms and kinetics of novel SCMs in a well-controlled environment. In this study, the focus lies on evaluating the early reactions of lime paste samples through isothermal calorimetry tests conducted at 40 °C. However, conventional mixing methods present experimental challenges. In-situ mixing fails to achieve proper paste homogenization, while ex-situ mixing results in a temperature difference at the start of testing due to the elevated testing condition of 40 °C. To address these concerns, a novel calorimetric methodology is proposed for early detection of reactivity responses. The main concept involves establishing a baseline correction for the temperature difference caused by ex-situ mixing, which is calibrated using an inert sample. This correction allows for the extraction of the heat generated by the early reactions. Combined with the Tian time correction, this methodology enables the evaluation of early reactions in lime paste samples measured with isothermal calorimetry at 40 °C within the first 100 min after mixing. The effectiveness of this methodology was demonstrated by evaluating the early reactions and the impact of potassium sulfate on three different types of metakaolin.

Use of biosolids from wastewater treatment plants and other organic fertilizers in agriculture—a preliminary results of a case study in banana cultivation in the Dominican Republic

IntroductionThe use of biosolids from wastewater treatment plants in agriculture is considered relevant for the promotion of sustainable agricultural practices, the improvement of soil fertility, and the reduction of dependence on synthetic chemical products. The Dominican Republic is today the world's largest producer of organic bananas and the main exporter of organic and fair-trade bananas to Europe. The biosolids generated in the wastewater treatment plants in the Dominican Republic currently have no use. In other countries, biosolids are used for agriculture, although biosolids have different characteristics in each place and their potential must be analyzed. In the Dominican Republic, there is no research that analyzes biosolids and their impact on agriculture. This research aims to compare the nutritional composition of bananas in plantations fertilized with different doses of biosolids and other organic fertilizers.MethodsFor this test, five blocks were prepared with organic fertilization, another with potassium sulfate, and a control block. Laboratory analysis was used to determine the characteristics of the biosolids used and also to know the nutritional composition of bananas of the Williams variety.ResultsThe results, when compared, show the impact that each of these fertilizers has or can have on the production of organic bananas in the Dominican Republic.DiscussionThe use of dose Y of the biosolid, characterized by the application of 16 kilograms of biosolid per plant, is the most recommended to fertilize the banana since the collected fruits presented the most optimal nutritional values.

Effect of Physico-Chemical Properties of Soil under Various Depths on Different Cropping Systems in Ayodhya, India

A research work conducted during 2018-19 at Agronomy farm of Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya (U.P.) to evaluate the fertility status and effect of different cropping systems on soil physico-chemical characteristics and their correlation. The 300 representative soil samples with 4 depths viz. 0-15, 15-30, 30-60 and 60-90 cm soil samples were taken with manually driven post hole auger and processed for soil analysis from different plots of Agronomy farm. Results revealed that physico-chemical properties viz. particle Density, bulk density pH, EC, organic corban, nitrogen phosphorus potassium Sulphur and zinc varied vertically and horizontally in cultivated and fallow lands. The soils were sandy loam, clay loam, loam and silt loam. The frequency distribution of soil bulk density of entire farm ranged from 1.128-1.58 Mgm-3, particle density ranged 2.50-2.76 Mgm-3 and soil chemical properties, like, pH ranged from 7.2-11.5, the E.C. is found in ranged from .13-1.01 dSm-1. While organic carbon was ranged from 1.4-6.70 g kg-1. and notable available Nitrogen in Agronomy farm was low in ranged from 170.15-221.36 kgha-1.The Phosphorus availability was found in ranged from 6.01-16.87 kgha-1 , while Potassium was found in ranged from 163.20-220.98 kgha-1. How ever the availability of Sulphur, was found in ranged from 8.62-18.32 kgha-1, Zinc ranged from in Agronomy farm 0.28-0.81mgkg-1. The significant positive correlation were observed among soil B.D with N, B.D with P, B.D with K, B.D with S, P.D. with S, P.D. with Zn. While the significant negative correlations were observed among PD with O.C., Zn with P, Zn with K and Zn with S in whole Agronomy Farm.

The effect of different concentrations of potassium sulfate on young Danio rerio

Danio rerio is widely used as a model object for various scientific studies, including environmental ones. In addition to assessing the survival of individuals and other research methods, the method of histological bioindicators is very indicative in toxicological experiments. As such markers, the liver and gills of fish were used in this work, which, when exposed to the substance under study, changed their structure, allowing us to judge the degree and nature of this effect. The present study examined the effects of potassium sulfate in concentrations from 100 to 1000 mg/l on the organs of danio. It was revealed that the negative effect of the substance on the gills of fish is mainly expressed in hyperemia and hyperplasia of the respiratory epithelium, and pathological changes in the liver are represented by both fatty embolism and damage to the liver tissue (ruptures, replacement with connective tissue). At the same time, the reaction of the organs was noted when exposed to the minimum of the studied concentrations — 100 mg/l.

Impact of Nutrient Application and Bagging on Development and Quality of Guava (Psidium guajava L.)

Guava is a tropical fruit known for its unique flavor and nutritional benefits. Guava is also recognized for its potential health benefits, including improved digestion and immune system support. The benefits of using calcium nitrate and potassium sulphate spraying in guava includes improved fruit size, enhanced nutrient uptake, increased fruit firmness, and better overall plant health. Calcium nitrate promotes cellular development and strengthens cell walls, while potassium sulphate along with bagging aids in fruit development and improves water uptake. These sprays can result in larger, firmer, and healthier guava fruits, contributing to better market value and consumer satisfaction. Therefore, the present investigation was carried out at the Department of Horticulture, Naini Agricultural Institute, Sam Higginbottom University of Agriculture Technology and Sciences, Prayagraj, Uttar Pradesh during the Rainy-2022-23 with a view to determine the effect of different nutrient applications and bagging on guava variety Allahabad Safeda for its growth quality and to work out the economics of various treatments. Under this experiment, overall, 10 treatment was prepared by spraying of different nutrients on plants and bagging of fruits with different polythene bags. From the above experimental finding it may be concluded that the treatment T7 (Ca (NO3)2 @ 2% + Bagging (Red colour Polythene) was found to be best in terms of physical parameters like fruit weight (147.27 g), fruit polar length (8.91 cm), fruit equatorial length (9.46 cm), fruit diameter (8.14 cm), fruit volume (697.02 cm3) among different treatment combinations of guava while T6 (Ca (NO3)2 @ 2% + Bagging (Yellow colour Polythene) and T9 (K2SO4 @ 2% + Bagging (Yellow colour Polythene) was found to be best in terms of quality parameters like TSS (10.12 °Brix), acidity (1.27%), ascorbic acid content (153.17 mg/100 g), reducing sugar (5.24%), total sugar (9.51%).

Pressure leaching of aluminum from kaolin by HCl: Experimental and DFT study

Kaolin is an important industrial mineral which has many industrial applications. It is also considered as an important source of aluminum; however, great technical challenges are required to be overcome to extract Al from kaolin. In this work, the extraction of aluminum from kaolin using HCl, as a leaching agent, was studied. Kaolin samples were collected from Wadi Al-Hafira, south of Jordan; these were crushed and ground to a particle size of 100% <75 μm. The ground samples were characterized in terms of chemical and mineral composition using X-ray fluorescence (XRF) and X-ray diffraction analysis (XRD) techniques. Kaolin was found to contain kaolinite, muscovite, and quartz as main mineral phases, in addition to anatase and hematite as trace mineral phases, while the chemical analysis revealed that kaolin contains about 36.1% Al2O3, 54% SiO2, 2.5% CaO, 1.96% Fe2O3 and 1.2% TiO2 as major oxides. The minor oxides were K2O, Na2O, and SO3. A microwave digestion vessel was used to provide a suitable environment for high pressure and temperature leaching. The effect of several leaching parameters was studied in this work including, leaching time (30 to 120 min), leaching temperature (80 to 200 °C), and molarity of leaching reagent (1, 2, 3 and 4 M). Additionally, two sources of HCl were used, including analytical grade HCl and HCl collected from the potassium sulphate industry. The extraction of four main elements were monitored during the leaching process employing ICP-OES multi element analysis technique, namely, aluminum, iron, titanium and silicon. The findings of this work suggest that the recovery of these elements increases with the increase of temperature and leaching time. The recovery of silicon decreased with the increase of acid molarity. Complete extraction of Al from kaolinite was obtained at temperatures above 180 °C and leaching time of 120 min, while Al present in muscovite was not amenable to leaching. However, traces of H2SO4 and chloride salts in waste HCl, from potassium sulphate industry, provided complete destruction of muscovite as evident from the XRD analysis of leach residues. Lower energy requirements (computed by DFT simulation) for chlorination of Al sites in reference to Si sites explains a higher recovery percentage of the former.

Facile fabrication of monodispersed α- and γ-Al2O3 microspheres through controlled calcination of alumina precursors synthesized by homogeneous precipitation

Monodispersed spherical particles of γ- and α-alumina were synthesized by urea-based homogeneous precipitation, using potassium sulfate and aluminum nitrate as the precursor and urea as a precipitating agent. The influence of various synthesis parameters like concentration of reactants, temperature, and reaction time, on the morphological features of alumina were investigated. Results showed that all the experimental parameters had a considerable effect on the morphology of the synthesized alumina, and control of these parameters resulted in monodispersed spherical particles with good dispensability and filtering performance. Extensive optimization of the experimental parameters led to produced alumina precursors with spherical morphology and an average particle size of 610 nm. The precipitated solids were characterized by various techniques and it was noted that the as-prepared particles were amorphous. Relatively well-dispersed and crystalline γ- and α-Al2O3 with higher sintering activity were obtained by calcining the as-synthesized precursors at 1000 and 1200 °C, respectively. The crystallographic results showed that crystallite size increased with an increase in annealing temperature. It was observed that the crystallite size of γ-Al2O3 was much smaller (5.71 nm ± 7.21%) than α-Al2O3 (35.40 nm) ± 4.58%. The Scanning electron microscopic analysis of the calcined alumina showed that the particle morphology was retained to a greater extent after calcination. The synthesized alumina particles can be used as a reinforcement filler in the Ni/Al2O3 composite coatings to enhance the tribological and mechanical properties of Ni-composite coating on a steel surface. The incorporated alumina particles in the composite may improve the properties of the coatings.

The Effect of Various Forms of Sulfur on Soil Organic Matter Fractions and Microorganisms in a Pot Experiment with Perennial Ryegrass (Lolium perenne L.).

This article focuses on the agronomic evaluation of the supplementation of mineral NPKMg fertilizers with elemental sulfur, magnesium, potassium, or ammonium sulfates in pot experiments with ryegrass growing in a sandy Arenosol with very low sulfur content. A benefit evaluation was carried out on the basis of biomass production, crop nutritional status, and changes in the content of soil organic matter fractions. Furthermore, the total number of bacteria, nitrogen-fixing bacteria, and fungi was estimated using the qPCR technique in soil samples after 60 days of ryegrass growth. The combined application of NPKMg and sulfur or sulfate fertilizers significantly increased the summary yield of three cuttings of fresh ryegrass biomass in the range of 32.3% to 82.7%. The application, especially in the form of sulfates, significantly decreased the content of free phenolic acids. Furthermore, compared to the control, i.e., soil with NPKMg applied alone, an increase in the content of glomalin-related proteins and a decrease in the amount of water-soluble organic carbon compounds were observed. Neither the number of DNA marker copy numbers of the total bacterial community nor the nitrogen-fixing bacteria were noticeably different. In turn, the total number of genetic markers for fungi was significantly higher in soils with potassium or ammonium sulfates compared to the control soil. The general results suggest that the application of sulfur fertilizers with NPKMg mineral fertilizer can benefit crops and support soil fertility due to the stabilization of aggregates and the decrease in water-soluble organic compounds.

Improvement of tomato yield and quality using slow release NPK fertilizers prepared by carnauba wax emulsion, starch-based latex and hydrogel nanocomposite combination

The modern agriculture is working on introducing new generation of fertilizers that apt to slow down the nutrients release to be more in synchrony with plant’s need throughout growth season, enhance fertilizer performance, and decrease nutrient losses into the environment. The aim of this research was to develop an advanced NPK slow-release fertilizer (SRF) and investigate its effect on yield, nutritional and morphological responses of tomato plant (Lycopersicon esculentum Mill.) as a model crop. To this goal, three water-based bio-polymeric formulations including starch-g-poly (acrylic acid-co-acrylamide) nanocomposite hydrogel, starch-g-poly(styrene-co-butylacrylate) latex, and carnauba wax emulsion were synthesized and used for production of NPK-SRF samples. Different samples of coated fertilizers (urea, potassium sulfate, and superphosphate granules) were prepared using different ratios of latex and wax emulsion, and for phosphorus and potash (R-treatment). Moreover, some of coated fertilizers (15 and 30 wt.%) was replaced with nanocomposite hydrogel containing fertilizers, named D and H treatments, respectively. The effect of SRF samples were compared with commercial fertilizers (NPK treatment) and a commercial SRF (T treatment), on the growth of tomato in the greenhouse, at two different levels (100 and 60). The efficiency of all the synthesized formulations were higher than NPK and T treatments, and among them, H100 significantly improved the morphological and physiological characteristics of tomato. For instance, amount of residual elements (nitrogen, phosphorus and potassium) as well as micro elements of calcium, iron and zinc in tomato cultivation bed and accordingly the uptake of these elements in the roots, aerial parts and fruits were increased in the R, H, and D treatments. The highest yield (1671.54 g), highest agricultural agronomy efficiency of fertilizer, and the highest dry matter percentage (9.52%) were obtained in H100. The highest amount of lycopene, antioxidant capacity and vitamin C was also observed in H100. Nitrate accumulation in tomato fruit in the synthesized SRF samples were decreased significantly compared to NPK100, and the lowest amount was observed in H100, which was 55.24% less than NPK100. Accordingly, it is suggested that combination of natural-based nanocomposite hydrogels along with coating latexes and wax emulsions can be a successful method to synthesize efficient NPK-SRF formulations for improvement of crop growth and quality.