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This paper describes a highly alkaline low-grade copper oxide ore. Copper can be selectively leached out while other metals are retained. A thermodynamic model of the CuO-(NH4)2SO4-NH3-H2O system was established for the leaching of tenorite (CuO) under conditions of mass and charge conservation. MATLAB's fitting functions, along with the diff and solve functions, were used to calculate the optimal ammonia concentration and total copper ion concentration of tenorite under different ammonium sulfate concentrations. The effects of various ammonia–ammonium salt solutions (ammonium sulfate, ammonium carbonate, ammonium chloride) on the copper leaching rate were investigated. Results show that under the conditions of an ammonia concentration of 1.2 mol/L, an ammonia–ammonium ratio of 2:1, a liquid–solid ratio of 3:1, a temperature of 25 °C, and a leaching time of 4 h, the copper leaching rate from the ammonium sulfate and ammonium chloride solutions reaches 70%, which is slightly higher than that of ammonium carbonate. Therefore, an ammonia–ammonium sulfate system is selected for leaching low-grade copper oxide due to its lower corrosion to equipment compared to the chlorination system. The impact of this study on industrial applications includes the potential to find more sustainable and cost-effective methods for resource recovery. The industry can reduce its dependence on resources and mitigate its environmental impact. Readers engaged in low-grade oxidized copper research will benefit from this study. [ABSTRACT FROM AUTHOR]

BACKGROUND: The olive fruit fly (OFF), Bactrocera oleae (Rossi), is the main insect pest of olive trees worldwide. Legislation limits to the use of some synthetic larvicidal insecticides is leading to the development of new control options for preventive control of adult flies. In the present study, the biological activity of four short‐chain aliphatic aldehydes, namely hexanal, (E)‐2‐hexenal, heptanal and (E)‐2‐heptenal, previously reported as repellents to the OFF adults was investigated. RESULTS: Electroantennography (EAG) recordings showed that antennae of OFF males and females are able to perceive the test compounds in a wide range of doses. In field trapping experiments, reservoir‐type polypropylene (PP) membrane dispensers loaded with individual compounds did not elicit a significant attraction of OFF males and females. On the contrary, a significant reduction of male catches was noticed when sex pheromone dispensers and PP membrane dispensers, loaded with one of the test compounds, were applied on the same white sticky traps ≈20 cm apart. Likewise, male and female catches in yellow sticky traps baited with ammonium carbonate (AC) dispensers as food attractant were significantly reduced by the presence of PP membrane dispensers of individual aliphatic aldehydes on the same traps. In small plots control trials, solid formulations of the four aldehydes into a bentonite clay support induced a significant reduction of the OFF active infestation mainly when C6 and C7 aldehyde‐activated bentonites were used. CONCLUSION: Short‐chain aliphatic aldehydes showed inhibitory effects on sex pheromone and food attractant‐mediated attraction of OFF. Results of field trials suggest potential of short‐chain aliphatic aldehydes to develop new semiochemical‐based OFF control options. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A gel-based floating matrix tablet was formulated and evaluated using the sublimation technique to enhance gastroretentive drug delivery. Anhydrous theophylline was employed as the active pharmaceutical ingredient, combined with sublimation agents and hydroxypropyl methylcellulose as the gel-forming polymer. The resulting tablets exhibited high porosity, immediate floatation, and sustained buoyancy for over 8 h. Optimization of the floating behavior and drug release profiles was achieved by adjusting the viscosity of and hydroxypropyl methylcellulose and the concentration of sublimation agents, specifically ammonium carbonate and menthol. These agents were selected for their effectiveness in creating a porous structure, thus reducing tablet density and enhancing floatation. Higher HPMC viscosity resulted in increased floating force, slower drug release, and improved swelling properties due to a slower erosion rate. A critical assessment of the balance between tablet porosity, mechanical strength, and drug release kinetics indicates that ammonium carbonate provided superior tablet hardness and lower friability compared to menthol, favoring a controlled release mechanism. The release dynamics of theophylline were best described by the anomalous (non-Fickian) diffusion model, suggesting a combined effect of diffusion and erosion. This research advances the development of gastroretentive drug delivery systems, highlighting the potential of sublimation-based floating matrix tablets for sustained drug release. [ABSTRACT FROM AUTHOR]

This is an article in the field of metallurgical engineering. Aiming at the limitation of low reactivity of barite and few chemical processing methods, a new soda ash conversion method is proposed. Firstly, the effect of barite reaction particle size, temperature, and sodium carbonate concentration on the production rate of barium carbonate by the hydrochloric acid hydrolysis method is explored. The results show that the sodium carbonate concentration has the greatest impact on the reaction conversion rate. At limited experimental conditions, when sodium carbonate is used when the concentration reaches 28.57%, the highest formation rate of barium carbonate reaches 90.05%. Secondly, in the subsequent reaction, ammonium chloride is selected to re-convert the barite conversion product to prepare ammonium carbonate. The barium carbonate produced by this method has a higher yield and purity. The new process breaks through the traditional misconception that barium sulfate does not react with soda ash. The process is simple and feasible, and ammonia and carbon dioxide can be recycled and reused, making the entire process a large cycle process, in line with the concept of green environmental protection, and recrystallization. The preparation of barium carbonate from stone provides a new production process.

Traditionally, biological methods are used to leaven dough semi-finished products in the production of bakery products. However, today consumers are increasingly including yeast-free bakery products in their diet. Given the growing demand for yeastfree bakery products, it is advisable to expand the range of products in this category. To ensure the formation of a developed crumb in yeast-free bakery products, chemical leavening agents are used in their production. Yeast-free bakery products were made using various fermented dairy products: ayran (2,0% fat), kefir (2,5% fat), bifidoyogurt (1,5% fat), and ryazhenka (4,0% fat). To determine the most effective fermented dairy product for the production of high-quality yeast-free bakery products, trial baking was conducted. Experimental dough samples were kneaded using two types of chemical leavening agents - sodium bicarbonate and ammonium carbonate. The dough was prepared using the straight dough method. The duration of dough resting after kneading was 20-30 minutes. The dough pieces were shaped into "okrayets" (small loaves): the dough was rolled to a thickness of 1,5 cm and the dough pieces were cut out with a cutter, placed on a sheet, and baked in a rack oven at 200-240°C for 16-18 minutes. The research results established that it is advisable to use ryazhenka in the production of yeast-free bakery products using fermented dairy products. At the same time, sodium bicarbonate should be included in the recipe to leaven the crumb. Such a product had the highest comprehensive quality index. Based on organoleptic and microbiological indicators, the product was found to have a shelf life of no more than 48 hours. To improve the taste and aromatic properties of the product, 3% malted barley extract and 4% white crystalline sugar were included in its composition. The developed yeast-free okrayets with ryazhenka was characterized by a higher content of bisulfitebinding substances, indicating an improved aroma of the product and a darker color of the crust and crumb. The developed product meets the body's needs for proteins by 31,5%, fats by 10,5%, carbohydrates by 49,0%, and dietary fiber by 18,3%.

This study analysed the composition and leaching results for 12 IFA samples from a local incineration plant by XRF and leaching tests based on BS EN12457-1:2002. XRF results show that the main elements are Ca, Cl and S in all IFA samples. Leaching test results shows a high leachability of Na, Cl, Br, Pb, Zn and Cu. The accelerated carbonation with (NH4)2CO3 was attempted to inhibit heavy metals leaching and remove soluble salts. The effect of (NH4)2CO3 concentration on carbonation efficiency and inhibition of heavy metal leaching was systematically investigated. TGA and ICP-MS were used to determine carbonation capacity and heavy metal leaching, respectively. TGA results show the maximum carbonation capacity is achieved in one hour with 10 wt% (NH4)2CO3 and 76% carbonation occurs -in the first 10 min. Leaching test results reveal that Cu and Pb are efficiently immobilised when the concentration of (NH4)2CO3 is as low as 2 wt% with a s/l ratio of 1:5 within 1 hr. Increasing the concentration of (NH4)2CO3 to 4 wt%, the leaching rate of Zn is also below NEA RVs (National Environment Agency of Singapore). Carbonation is also effective to immobilise Cd and Ni, but not for Cr since it exists as CrO42- and cannot be carbonated. XRF results from a larger scale reaction confirm the significant removal of soluble salts, and lower leachability (except SO42-) is substantiated by leaching tests. By integrating the processes of CO2 capture with ammonia and accelerated carbonation, our work contributes to CO2 sequestration and IFA detoxification.

Biocementation is an exciting biomanufacturing alternative to common cement, which is a significant contributor of CO2 greenhouse gas production. In nature biocementation processes are usually modulated via ureolytic microbes, such as Sporosarcina pasteurii, precipitating calcium carbonate to cement particles together, but these ureolytic reactions also produce ammonium and carbonate byproducts, which may have detrimental effects on the environment. As an alternative approach, this work examines biosilicification via surface-displayed silicatein-α in bio-engineered E. coli as an in vivo biocementation strategy. The surface-display of silicatein-α with ice nucleation protein is a novel protein fusion combination that effectively enables biosilicification, which is the polymerization of silica species in solution, from the surface of E. coli bacterial cells. Biosilicification with silicatein-α produces biocementation products with comparable compressive strength as S. pasteurii. This biosilicification approach takes advantage of the high silica content found naturally in sand and does not produce the ammonium and carbonate byproducts of ureolytic bacteria, making this a more environmentally friendly biocementation strategy. [ABSTRACT FROM AUTHOR]

Traditionally, biological methods are used to leaven dough semi-finished products in the production of bakery products. However, today consumers are increasingly including yeast-free bakery products in their diet. Given the growing demand for yeastfree bakery products, it is advisable to expand the range of products in this category. To ensure the formation of a developed crumb in yeast-free bakery products, chemical leavening agents are used in their production. Yeast-free bakery products were made using various fermented dairy products: ayran (2,0% fat), kefir (2,5% fat), bifidoyogurt (1,5% fat), and ryazhenka (4,0% fat). To determine the most effective fermented dairy product for the production of high-quality yeast-free bakery products, trial baking was conducted. Experimental dough samples were kneaded using two types of chemical leavening agents - sodium bicarbonate and ammonium carbonate. The dough was prepared using the straight dough method. The duration of dough resting after kneading was 20-30 minutes. The dough pieces were shaped into "okrayets" (small loaves): the dough was rolled to a thickness of 1,5 cm and the dough pieces were cut out with a cutter, placed on a sheet, and baked in a rack oven at 200-240°C for 16-18 minutes. The research results established that it is advisable to use ryazhenka in the production of yeast-free bakery products using fermented dairy products. At the same time, sodium bicarbonate should be included in the recipe to leaven the crumb. Such a product had the highest comprehensive quality index. Based on organoleptic and microbiological indicators, the product was found to have a shelf life of no more than 48 hours. To improve the taste and aromatic properties of the product, 3% malted barley extract and 4% white crystalline sugar were included in its composition. The developed yeast-free okrayets with ryazhenka was characterized by a higher content of bisulfitebinding substances, indicating an improved aroma of the product and a darker color of the crust and crumb. The developed product meets the body's needs for proteins by 31,5%, fats by 10,5%, carbohydrates by 49,0%, and dietary fiber by 18,3%. [ABSTRACT FROM AUTHOR]

We believe our poly(lactic acid) (PLA) microbubbles are well suited for therapeutic delivery to spinal cord injury (SCI) using ultrasound-triggered bursting. We investigated the feasibility of clinical ultrasound bursting in situ , the optimal bursting parameters in vitro and the loading and release of a model bio-active DNA. Microbubbles were tested using clinical ultrasound in a rat cadaver SCI model. Burst pressure thresholds were determined using the change in enhancement after ultrasound exposure. Resonance frequency, acoustic enhancement, sizing and morphology were evaluated by comparing two microbubble porogens, ammonium carbonate and ammonium carbamate. Oligonucleotides were loaded into the shell and released using the found optimized ultrasound bursting parameters. In situ imaging and bursting were successful. In vitro bursting thresholds using frequencies 1, 2.25 and 5 MHz were identified between peak negative pressures 0.2 and 0.5 MPa, believed to be safe for spinal cord. The pressure threshold decreased with decreasing frequencies. PLA bursting was optimized near the resonance frequency of 2.5 to 3.0 MHz using 2.25 MHz and not at lower frequencies. PLA microbubbles, initially with a mean size of approximately 2 µm, remained in one piece, collapsed to between 0.5 and 1 µm and did not fragment. Significantly more oligonucleotide was released after ultrasound bursting of loaded microbubbles. Microbubble-sized debris was detected when using ammonium carbamate, leading to inaccurate microbubble concentration measurements. PLA microbubbles made with ammonium carbonate and burst at appropriate parameters have the potential to safely improve intrathecal therapeutic delivery to SCI using targeted ultrasound. [ABSTRACT FROM AUTHOR]

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The activation of carbon monoxide by the presence of oxygen vacancies is widely recognized as a crucial step in the direct synthesis of light olefins from syngas. However, little research has been reported on increasing the concentration of oxygen vacancies on the surface by changing the coprecipitated oxide scrubbing solution. In this study, ZnCrAl oxides were synthesized utilizing an innovative method involving the utilization of ammonium carbonate solution as the washing solution. XPS, NH3-TPD, BET, and XRD tests were used to look at the samples. They showed that the samples under study have more oxygen vacancies, a more acidic surface, and a larger specific surface area than the water-washed co-precipitated oxides and sol-gel oxides. The quantity of ZnO was decreased. Moreover, there was increased catalytic activity in the investigated samples. When employed as a bifunctional catalyst alongside SAPO-34 for the catalytic reaction of syngas, the conversion of CO was observed to reach 55.48%, while the yield of light olefins reached 28.36%. Because of this, using an ammonium carbonate solution to clean the co-precipitated oxides is a very good idea for further research. This approach offers a new direction to enhance the presence of oxygen vacancies on the oxides' surface and investigate the structural correlation. [ABSTRACT FROM AUTHOR]

γ-Al 2 O 3 with a high density of active sites has been widely used. In this study, γ-Al 2 O 3 powder with a high specific surface area and a high purity is prepared through facile ammonium salt-assisted calcination. During the calcination process, the gases (NH 3 and CO 2) generated from ammonium salts can manipulate the pore and crystal structures to obtain active γ-Al 2 O 3 with a high purity of above 99.99 %. The results demonstrate that the specific surface areas of γ-Al 2 O 3 obtained by the use of ammonium carbonate (AC), ammonium bicarbonate (AB), and ammonium acetate (AA) are 441.35, 459.23, and 427.32 m2 g−1, respectively. Moreover, the γ-Al 2 O 3 obtained with ammonium salt shows a higher content of AlO 6 than the blank group, contributing to the formation of a sponge-like morphology and more active sites. Furthermore, the active γ-Al 2 O 3 exhibits good performance in adsorption and desorption, making it highly valuable in various applications. [ABSTRACT FROM AUTHOR]

The method of fabrication of solid solution powder of uranium/plutonium (38%) oxides from the pulp of ammonium uranyl-plutonyl carbonate process (AUPuC) by microwave radiation in reducing and atmospheric environments was proposed and tested at the laboratory level. For research the pulp was prepared, obtained by co-precipitation of uranium and plutonium from nitrate solution (simulator for stripping product). The process consists of three main stages: oxidation of Pu(IV) to Pu(VI), precipitation, and conversion in a laboratory microwave unit. According to data of the X-ray diffraction analysis the powders synthesized in a reducing atmosphere and an atmospheric environment are a solid cubic solution (UxPu1–x)O2 and (PuO2, U3O8) mixed oxide, respectively. Scanning electron microscopy and electron probe microanalysis of the powder obtained in an atmospheric environment showed a fairly uniform distribution of U, Pu, and O in the solid phase. [ABSTRACT FROM AUTHOR]

A series of La–Ce–MnOx catalysts derived from the precipitation of acetate salt and ammonium carbonate were calcined at different temperatures and applied for the catalytic oxidation of soot from diesel exhausts. The structure states of the as-prepared catalysts and catalytic behaviour for soot oxidation were studied by many characterization techniques such as XRD, XANES, N2 adsorption–desorption, TPR, O2-TPD, XPS and TGA. XANES results display most Mn species are Mn4+ when the samples are calcined at 500 and 600°C. However, for MCLa-700 and MCLa-800 catalysts, the predominance valence is 3+ ions. The MCLa-500 and MCLa-600 catalysts possess higher concentrations of surface active oxygen evidenced by H2-TPR and soot-TPR. Therefore, the combustion rate of soot over MCLa-600 catalyst is remarkably increased with the T10, T50 and T90 at 318°C, 360°C and 388°C under NOx atmosphere respectively. [ABSTRACT FROM AUTHOR]

The preparation process for the composites CuO/ZnO/γ-Al2O3, which can be used as the main component of catalysts for large-tonnage methanol production and carbon monoxide conversion, was investigated by means of x-ray phase, x-ray crystalline, and synchronous thermal analysis as well as scanning electron microscopy, and low-temperature adsorption-desorption of nitrogen. The influence of the production method and the nature and intensity of processing on the phase composition of the resulting precursors and the physicochemical properties of the resulting composites was determined. The processes occurring at the stage of mechanochemical activation of a mixture of anhydrous oxides CuO/ZnO/γ-Al2O3 and a mixture of oxides with ammonium carbonate and ethanedioic [oxalic] acid were studied. The optimal parameters for obtaining CuO/ZnO/γ-Al2O3 composites with a developed specific surface and porous structure were determined. [ABSTRACT FROM AUTHOR]

The present study aimed to compare some commercial traps baited with ammonium carbonate for their efficacy in monitoring Bactrocera oleae (Rossi) and their selectivity toward beneficial insects, under the conditions of olive groves located in five Mediterranean countries (Greece, Italy, Lebanon, Spain, Tunisia). The selectivity of the devices was evaluated toward several groups of non-target insects, namely lacewings (Chrysopidae), hoverflies (Syrphidae), ladybirds (Coccinellidae), bees (Apoidea) and hymenopteran parasitoids. The following devices were compared: yellow sticky panel, green sticky panel, Jackson trap with different combinations of yellow and white colours of the device and/or the panel, and McPhail trap. In most cases, the McPhail trap and the yellow panel showed the highest efficacy in monitoring male and female B. oleae flies; however, the yellow panel was most attractive for some groups of non-target insects, particularly the hymenopteran parasitoids, whereas the comparative non-target effects were sitespecific for the other arthropod groups. In the case of Chrysopidae, McPhail caught more individuals than the other traps in Italy and Spain, whereas in Lebanon and Greece, the highest number of individuals was captured in the two sticky panels. Coccinellidae were found in very low numbers only in Lebanon on yellow panels. Syrphidae were captured mainly on sticky panels in Greece and Tunisia. Apoidea were found only on yellow panels in Lebanon. The choice between the McPhail trap and the yellow panel should be made on the basis of various evaluations carried out at the site, including operational ones. [ABSTRACT FROM AUTHOR]

In order to analyze trace rare earth impurities in ThF4, two effective analytical methods based on the matrix-matched strategy using ICP-MS with different sample pretreatment procedures are developed in this study. The first procedure involves the conversion of ThF4 into ThO2 by pyrohydrolysis and the subsequent dissolution of ThO2 in 3M HNO3. In the second procedure, ThF4 is directly dissolved into hot ammonium carbonate solution. The detection limits, precisions, and recovery rates of both methods were investigated. For the 15 rare earth elements (REEs), the detection limits of the methods are in the range of 0.001–0.077 µg g−1. The recoveries of the rare earth impurities with concentrations of 0.05–50 µg g−1 ranged mostly from 96 to 110%, and the relative standard deviations have been determined to be less than 8%. Both analytical methods are composed of simple and green processes without generation of organic waste. [ABSTRACT FROM AUTHOR]

With the growth of the new energy industry, the requirements for manganese have increased significantly. In this paper, the method of manganese extraction from pyrolusite using ammonium sulfate roasting and water leaching was presented. At the optimal process parameters: mass ratio of (NH4)2SO4 to pyrolusite of 2:1, the roasting temperature of 420°,C and duration of 120 min, the leaching efficiency of Mn and Fe was 94.55% and 54.38%, respectively. The mechanism analysis shows that MnO2 and Fe2O3 in pyrolusite were converted to (NH4)2Mn2(SO4)3, (NH4)3Fe(SO4)3, and NH4Fe(SO4)2 by roasting with ammonium sulfate. Iron was removed from the leaching solution with the addition of ammonia. Afterward, manganese carbonate products were prepared from iron‐free manganese sulfate solution by adding ammonium carbonate at a stirring duration of 60 min, a reaction temperature of 40°C, a pH of 7, and a molar ratio of ammonium carbonate to the manganese of 1.1:1, the precipitation efficiency of manganese could reach 99.8%, and the obtained manganese carbonate products were compliant with the industry standards. The ammonia released during the roasting process could be absorbed to regenerate (NH4)2SO4 and the final filtrate after evaporation and crystallization could be used to recycle (NH4)2SO4, both of which were used again into roasting process to reduce the consumption of raw material. In this process, the roasting temperature was only 420°C, which was significantly lower than the pyrometallurgical process suggested in earlier studies. [ABSTRACT FROM AUTHOR]

The possibility of using the fractional precipitation of rare-earth metals (REMs) and manganese from hydrochloric acid solutions by ammonium carbonate is considered. Specific features of the behavior of elements during precipitation, which are necessary to know when preparing selective REM and manganese concentrates, have been revealed. At pH 5.25, 85% ΣTR2O3 pass to a deposit (in the oxide formula, ΣTR is the commonly accepted international designation of REMs), and the REM content is 60.5%. At pH 5.25–7.4, 92% manganese are extracted to a manganese concentrate, and the MnO content in the concentrate reaches 70.7%. The complicated chemical composition of the solution requires three-stage fractional precipitation for preparing qualitative selective concentrates: iron and thorium should be precipitated as a cake at the first stage, and REMs and manganese should be precipitated at the second and third stages, respectively. This makes it possible to form deactivated concentrates in the form of carbonates suitable for the further extraction of REMs and manganese by the well-known methods. [ABSTRACT FROM AUTHOR]

A green method for synthesizing 1,4-dihydropyridines (1a-j) by a one-pot reaction of various aldehydes, ethyl acetoacetate, and ammonium carbonate, catalyzed by a seashell and kaolin powders, mixed and calcined at 500 and 800 °C, under solvent-free conditions, has been developed. The catalyst was characterized by physicochemical techniques, namely, X-ray diffraction (XRD), electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The mixture composed of 20% seashell and 80% Kaolin (Q3-500), calcined at 500 °C, gave the best results (78 to 96% yields). Q3-500 separation from the reacting medium was carried out by filtration and reused several times with a slight decrease in yields. Compared with other conventional methods, the present method is inexpensive and offers advantages, namely: the catalyst is eco-friendly, recyclable, and gives high yields with shorter reaction time. A seashell/Kaolin calcined system (20/80) at 500°C was elaborated to catalyze the Hantzsch reaction under solvent-free conditions. Using Q3-500 six times gave dihydropyridines with excellent yields with a slight loss of activity. The improvement of the catalytic properties of the kaolin surface is due to the increase of cationic content. [ABSTRACT FROM AUTHOR]

In this study, the waste neem leaves (Azadirachta indica) gained visible attraction for neem leaf–activated carbon (NLAC) preparation in the thermal process by using ammonium carbonate as an activating agent. Using NLAC, a nanocomposite of NLAC/Fe2O3 was synthesized by hydrothermal techniques for Cr(VI) elimination from the aqueous solution. The formation of NLAC/Fe2O3 composite was additionally confirmed by the use of various powerful investigative techniques such as FE-SEM, VSM, TEM, EDX, FT-IR, XRD, and BET. The NLAC/Fe2O3 has a saturation magnetization of 1.18 emu/g and surface area and pore volume of 245.2 m2/g and 0.038 cm3/g, respectively. The composite has crystalline structure and the average particle size of Fe2O3 present on the activated carbon surface was about 14–17 nm. The BBD (Box-Behnken design) model was used for Cr(VI) removal and the obtained R2 and adj-R2 values for the model were very high about 0.9805 and 0.9555. The ANOVA data indicated that the Cr(VI) model was a statistically significant one with the F and p values of 39.17 and 0.0001. About 91.4% of Cr(VI) was removed by NLAC/Fe2O3 composite in the optimized condition of 0.05 g of adsorbent dose, solution pH 3.58, and initial Cr(VI) solution of 10.42 mg/L respectively. The adsorption of Cr(VI) on NLAC/Fe2O3 composite was imitated by the Langmuir isotherm model (R2 = 0.98), proceeded with the pseudo-second-order kinetics model (R2 = 0.99), and the maximum uptake capacity as calculated from the isotherm was 188.71 mg/g. The adsorption process was endothermic and adsorbent can be used for up to four cycles. This study showed that NLAC/Fe2O3 composite could be employed as an effective, affordable cost adsorbent to remove pollutants from wastewater. [ABSTRACT FROM AUTHOR]

The conductometric method is used to study the dependences of the electrical conductivity (EC) of aqueous solutions of ammonium carbonate and solutions of the ammonium carbonate–ammonium perrhenate system on the reagent content in the concentration range 0.1–1.8 mol/L for (NH4)2CO3 and 0.01–0.1 mol/L for NH4ReO4 and on the solution temperature in the range 20–50°C. EC is found to increase linearly with the electrolyte temperature and nonlinearly with the reagent concentration. The temperature coefficients of EC and its activation energies are calculated in the concentration and temperature ranges under study. The EC activation energy is found to decrease as the solution temperature increases. The calculated EC activation energies indicate a diffusion character of charge transfer. [ABSTRACT FROM AUTHOR]

Molybdenum sulfide nanoparticles have an important role in catalytic behavior of hydroconversion catalyst. The extraction of Mo is a crucial issue because of great consumption, environmental regulations, high cost and depletion of high grades resources. In this work, Plackett-Burman design as a screening method is used to analyze the effects of six variables with the intent to increase the efficiency of molybdenum recovery from homogenous nanocatalysts in the slurry phase hydroconversion processes. These variables consist of leaching temperature, oxidation temperature, leaching time, oxidation time, hydrogen peroxide concentration, and ammonium carbonate concentration. This design offers the significant role of parameters that determining optimum recovery conditions for achieving the cost-efficient, shorter duration and more environmentally friendly process. The results show that the leaching time, hydrogen peroxide concentration, and ammonium carbonate concentration are effective parameters on molybdenum concentration with a degree of confidence of 95%. Based on the obtained results, the influences of leaching and oxidation temperatures and oxidation time were negligible. A linear model was obtained to predict operation conditions by effective parameters for estimating recovery. The maximum recovery is achieved at minimum leaching time (20 min), minimum hydrogen peroxide concentration (10vol %) and maximum ammonium carbonate concentration (7wt %). [ABSTRACT FROM AUTHOR]

Mining waste is a serious environmental problem in all countries where mining is carried out. Considering large amount of mining waste from the exploitation and processing of nickel laterites in Cuba and Brazil, the work takes as a hypothesis that, if it demonstrates the real possibility of using such waste as a partial substitute for aggregates in the production of asphalt concrete, the negative environmental impact caused by them in the places where they are deposited could be reduced. The objective of the work is, to demonstrate the suitability of mining waste from nickel and cobalt processing dams in the municipalities of Moa and Nicaro, in the province Holguín, Cuba. Such wastes come from Ammonium Carbonate Leaching and Pressurized Acid Leaching processes. The research methodology it has based on taking representative samples from the waste dams, their subsequent physical, chemical and mineralogical characterization, and the characterization of the aggregates and asphalt cement used in the mixtures under study. The design of the asphalt concrete mixtures was carried out using the Marshall method. Subsequently, a comparative analysis was made on the behavior of the asphalt concretes made with limestone and mining waste fillers investigated. It's demonstrated, from the results of the laboratory tests, that it is possible to manufacture asphalt concretes with the use of mining residues from the processing of nickel laterites from Moa and Nicaro, satisfactorily fulfilling the required technical parameters. [ABSTRACT FROM AUTHOR]

The paper describes cementation as a suitable method applied in the refining of EAFD leachates in order to obtain required purity of ZnO for specific industrial application. For study of cementation conditions, the leachate from alkaline leaching with (NH4)2CO3 was used. The leachates contained a high amount of zinc (8000–12,000 µg/mL) and a low content of impurities such as iron, lead, copper, chromium and manganese in the range of 1–21 µg/mL. Cementation conditions were predicted by thermodynamic study, theoretically confirming the viability of the proposed experiments at the considered pH = 8–9. Cementation experiments were carried out using powdered zinc and aluminium (5 g/L) as cementation agents in the first phase separately. To increase the cementation efficiency, their combination was used (2.5:2.5 g/L or 5:5 g/L) at temperatures of 20, 40, 60 and 80 °C for 30 min. The optimum cementation conditions were established as: Zn:Al = 5:5 g/L, 60 °C. Under the given conditions, 100% of Fe, Cu, Pb and Mn were removed from the leachate. The ZnO with the maximum purity of 96.67% was obtained by crystallization of cemented leachate at 105 °C, followed by calcination at 900 °C for 4 h. ZnO with such a purity is suitable for use in the electrical or rubber industries. [ABSTRACT FROM AUTHOR]

A particular bird's nest-like pseudo-boehmite (PB) composed of cohesive nanostrips was prepared by a novel and facile approach based on the reaction of Al–Ga–In–Sn alloy and water, together with ammonium carbonate. The PB possesses a large specific surface area (465.2 m2 g−1), pore volume (1.0 cm3 g−1), and pore diameter (8.7 nm). Subsequently, it was utilized as a precursor to form the TiO2/ γ -Al2O3 nanocomposite for tetracycline hydrochloride removal. The removal efficiency can reach above 90% at TiO2:PB = 1:1.5 under the Sunlight irradiation simulated by a LED lamp. Our results indicate that the nest-like PB is a promising carrier precursor for efficient nanocomposite catalysts. [ABSTRACT FROM AUTHOR]

The use of the commercial simulator Aspen Plus® could bring an amelioration in the accuracy of the predictions of the chemical species composition in the output streams of the anaerobic digestion process. Compared to the traditionally employed lumped models, which are elaborated from scratch, the models implemented in Aspen Plus® have access to a broad library of thermodynamic and phenomena transport properties. In the present investigation, a process simulation model for anaerobic digestion has been prepared by including a stoichiometric-equilibria reactor to calculate the extent of the ionization of the molecules present in the anaerobic digestate. The model characterizes the technical feasibility of anaerobic digestate stabilization, by means of biomass ash-based treatment, for the production of an organic fertilizer and potential biogas upgradation with the synthesis of ammonium carbonate. First of all, the titration of the manure digestate with the hydrochloric acid showed that a dose of 3.18 mEq/g would be required to attain the targeted pH of zero-point charge, upon addition of the sewage sludge ash in a ratio to the manure digestate of 0.6 ± 0.2%. Secondly, the profiles of ammonia, carbon dioxide, and methane found in the biogas agree with the pH of the treated digestate and enable the upgrading of the biogas with the production of NH4HCO3. The model needs to be further developed to ensure the standards are attained in all output streams of stabilized anaerobic digestate, biomethane, and isolated added-value chemical fertilizers. [ABSTRACT FROM AUTHOR]

Ammonium carbonates are a group of fertilizer materials that include ammonium bicarbonate, ammonium carbonate hydrate, and ammonium carbamate. They can be synthesized from diverse nutrient-bearing liquid waste streams but are unstable in a moist environment. While extensively utilized several decades ago, their use gradually decreased in favor of large-scale, facility-synthesized urea fertilizers. The emergence of sustainable agriculture, however, necessitates the recovery and reuse of nutrients using conventional feedstocks, such as natural gas and air-derived nitrogen, and nutrient-containing biogenic waste streams. To this extent, anaerobic digestion liquid presents a convenient source of solid nitrogen and carbon to produce solid fertilizers, since no significant chemical transformations are needed as nitrogen is already present as an ammonium ion. This review describes detailed examples of such feedstocks and the methods required to concentrate and crystallize solid ammonium carbonates. The technologies currently proposed or utilized to stabilize ammonium carbonate materials in the environment are described in detail. Finally, the agricultural efficiency of these materials as nitrogen and carbon source is also described. [ABSTRACT FROM AUTHOR]

This article describes the production of nanodisperse xerogel and powders (average CSR size of 9 nm) in the ZrO2–Y2O3–Al2O3 system by coprecipitation of hydroxides. A strong highly porous ceramic has been produced from the initial powder with the composition of [(ZrO2)0.97(Y2O3)0.03]0.8(Al2O3)0.2 with pore forming additives using patented solid phase sintering. Using Doppler sonography, the volume of blood flow in arteriolas and capillaries has been estimated 150 and 250 days after implantation of plates. Therefore, the microcirculatory Doppler sonography seems to be a promising intravital method of estimating blood flow in the zone of plates from biocompatible nonresorbable material and, probably, inside the plates. It has been found that the ceramic plates based on zirconium dioxide in the body of experimental animals do not result in a negative reaction of animal's body. The in vivo experimental results make it possible to state that the obtained bioceramic based on zirconium dioxide is a promising material for endoprosthetics. [ABSTRACT FROM AUTHOR]

The separation of dimethyl carbonate (DMC) and methanol is of great significance in industry. In this study, ionic liquids (ILs) were employed as extractants for the efficient separation of methanol from DMC. Using the COSMO-RS model, the extraction performance of ILs consisting of 22 anions and 15 cations was calculated, and the results showed that the extraction performance of ILs with hydroxylamine as the cation was much better. The extraction mechanism of these functionalized ILs was analyzed by molecular interaction and the σ-profile method. The results showed that the hydrogen bonding energy dominated the interaction force between the IL and methanol, and the molecular interaction between the IL and DMC was mainly Van der Waals force. The molecular interaction changes with the type of anion and cation, which in turn affects the extraction performance of ILs. Five hydroxyl ammonium ILs were screened and synthesized for extraction experiments to verify the reliability of the COSMO-RS model. The results showed that the order of selectivity of ILs predicted by the COSMO-RS model was consistent with the experimental results, and ethanolamine acetate ([MEA][Ac]) had the best extraction performance. After four regeneration and reuse cycles, the extraction performance of [MEA][Ac] was not notably reduced, and it is expected to have industrial applications in the separation of methanol and DMC. [ABSTRACT FROM AUTHOR]

Chickpea is considered among the most important leguminous crops in the world but is not a regular meal pulse due to their long cooking time and lengthy preparatory procedure. This gives rise to the need of converting raw chickpea into convenient food. For the preparation of instant chickpea from Desi and Kabuli variety, Central Composite Rotatable Design (CCRD) under Response Surface Methodology (RSM) was employed which consisted of four variables i.e. sodium chloride (NaCl), sodium bicarbonate (NaHCO3), ammonium carbonate (NH4)2CO3 and temperature for soaking treatments. This design was used to develop models for the soaking time, change in colour, split %, alkalinity and cooking time for prepared instant chickpea samples. High-temperature hydration (60 °C) required lesser time to achieve the maximum hydration, whereas low-temperature hydration (30 °C) enhanced the hydration time and reduced the cooking time of instant chickpea significantly (P≤ 0.01) but this condition was inverse for the splitting/butterfly defects. Increasing the concentration of sodium bicarbonate and ammonium bicarbonate from 0.5 to 1.5 % during soaking treatments increased the splitting and alkalinity and produced undesirable colours in treated samples of chickpea. RSM optimized values concerning concentrations of different salts i.e. NaCl, NaHCO3, and (NH4)2CO3 in soaking solution were 0.59, 0.85 % and 0.82 %, respectively at 49.81 °C temperature for Desi instant chickpea having 11 minutes of cooking time whereas corresponding values for Kabuli chickpea were 1.07 % NaCl, 0.79 % NaHCO3, and 0.70 % (NH4)2CO3 at 46.53 °C temperature with 13 min cooking time. [ABSTRACT FROM AUTHOR]

Simple synthetic routes to regioselectively deuterated tris[2‐(dimethylamino)ethyl]amine (Me6TREN) variants are described. Imine formation with formaldehyde‐d2 from tris(2‐aminoethyl)amine (TREN) and subsequent reductions with NaBD4 afforded N[CH2CH2N(CD3)2]3 or d18‐Me6TREN in 79 % yield. A trisubstitution protocol from 2‐bromo‐N,N‐dimethylacetamide and ammonium carbonate and subsequent reduction of the N(CH2CONMe2)3 intermediate by lithium aluminum deuteride has afforded N[CH2CD2N(CH3)2]3 or (d6‐arm)‐Me6TREN in three steps and 52 % overall yield. A similar protocol from 2‐bromo‐N,N‐dimethyl‐d2‐acetamide, obtained in two steps from d4‐acetic acid, with reduction of the N(CD2CONMe2)3 intermediate by lithium aluminum hydride has afforded N[CD2CH2N(CH3)2]3 or (d6‐cap)‐Me6TREN in four steps and 13 % overall yield from CD3COOD. [ABSTRACT FROM AUTHOR]

Controllable release of chemotherapeutic drugs in tumor sites remains a big challenge for precision therapy. Herein, we developed acidity/carbon dioxide (H+/CO 2)-sensitive poly (ethylene glycol)- b -poly (2-(diisopropylamino) ethyl methacrylate)- b -polystyrene triblock polymer (PEG- b -PDPA- b -PS) grafted photoactivated vesicles for programmed release of chemotherapeutic drugs against glioblastoma. In brief, gold nanoparticles (GNPs) were firstly tethered with the H+/CO 2 -sensitive PEG- b -PDPA- b -PS polymer. Next, the CO 2 precursor (ammonium bicarbonate, NH 4 HCO 3) and doxorubicin (DOX) were loaded during self-assembly process of PEG- b -PDPA- b -PS-tethered GNPs, thus obtaining the multifunctional gold vesicles (denoted as GVND). The programmed multi-stimuli responsive drug release by GVND was undergone in multiple steps as follows: 1) the vesicular architecture of GVND was first swelled in tumor acidic microenvironment, 2) the GVND were partially broken under near-infrared (NIR) laser irradiation, 3) the mild hyperthermia generated by GV triggered the thermal decomposition of encapsulated NH 4 HCO 3 , leading to the in situ generation of CO 2 , 4) the generated CO 2 reacted with PDPA of PEG- b -PDPA- b -PS, changing the hydrophilicity and hydrophobicity of GVND, thus vastly breaking its vesicular architecture, finally resulting in a "bomb-like" release of DOX in tumor tissues. Such a multi-stimuli responsive programmed drug delivery and mild hyperthermia under NIR laser activation displayed strong antitumor efficacy and completely eradicated U87MG glioblastoma tumor. This work presented a promising strategy to realize precision drug delivery for chemotherapy against glioblastoma. • An acidity/carbon dioxide-sensitive triblock polymer is synthesized. • Multi-stimuli responsive gold vesicles (GVND) co-loaded with ammonium bicarbonate (NH 4 HCO 3) and doxorubicin (DOX) are prepared. • The GVND are progressively responsive to tumor acidic microenvironment, light irradiation, and the in situ generated CO 2. • The GVND have the potential to be used for multi-stimuli responsive programmed release of DOX against glioblastoma. [Display omitted] [ABSTRACT FROM AUTHOR]

The recovery of valuable metals in spent lithium-ion batteries (LIBs) is not only environmentally sustainable but also economically advantageous. In this research, ammoniacal leaching process was adopted to selectively extract valuable metals from the mixed types of cathode active materials. By employing the ammonium sulphite as the reductant, while the ammonia and ammonium carbonate are used to provide NH3 to complex metal elements. The Eh–pH diagrams were used to study the extraction behaviour of Co, Li, Ni and Mn during ammoniacal leaching, and the Co, Ni can be leached out as the complexes ([Ni(NH3)n]2+, [Co(NH3)m]2+), while the Li was leached out as metallic ion. Manganese is first leached out as [Mn(NH3)β]2+ and then precipitated as (NH4)2Mn(SO3)2·H2O and (NH4)2Mn(SO4)3 when an excess of ammonium sulphites added to the solution. A detailed understanding of the ammoniacal selective leaching process is carried out by investigating the effects of factors such as reaction temperature (50–90 ℃), leaching time (2–6 h), agitation intensity (400–900 rpm) and solid-to-liquid ratio (10–50 g/L). The experiment of response surface methodology shows that significant interactions exist between ammonium sulphite and ammonium carbonate, ammonium sulphite and ammonia according to the leaching efficiency of Co. Under the optimum conditions, Co, Li, Ni, Mn and Al can be leached out with the efficiencies of 84.56%, 90.31%, 64.13%, 4.53% and 1.72%, respectively. The results proved the possibility of selective leaching. Summarily, this research is potentially beneficial for the design of a selective recycling technique. [ABSTRACT FROM AUTHOR]

Smalt is a blue cobalt-coloured glass pigment used in European wall paintings from the early Renaissance period that became a popular choice for artists due to its unique tone, availability, and versatility. The pigment has long been considered as stable in an alkaline environment since it was applied with lime-based techniques and generally retained its colour over time. This perceived stability has meant that aqueous-based alkaline treatments, often involving high pH values, substantial quantities of liquid, and long contact times, have been used in conservation treatments. However, studies of the kinetics of glass deterioration in the past few years have demonstrated that glass is highly reactive in contact with water and substances with both high and low pH values. Research into smalt deterioration in canvas paintings has shown that smalt is susceptible to elemental leaching and physical changes in contact with water and low pH values; however, there is little specific information about the conservation implications of these findings on the treatment of smalt in wall paintings. This experimental study explores several aspects of how aqueous-based alkaline conservation treatments affect smalt grains in lime-based wall paintings: the influence of painting technique, exposure of the pictorial layer to water before treatment, and pH values and contact times during treatment. Replicas representing three different painting techniques were created, exposed to liquid water or water vapour, and treated with three substances commonly used in conservation according to accepted practices in terms of preparation and application. Chemical and physical changes in the pigment were then analysed using scanning electron microscopy with energy dispersive X-ray spectroscopy. Results confirmed that aqueous-based alkaline substances provoke chemical changes as well as physical deterioration in smalt applied in lime-based techniques evidenced by leaching, corrosion, and cracking in the pigment grains. Crucial factors found to influence the impact of treatments on smalt included the previous exposure to humidity of the pictorial layer, the pH value of the treatment, and extended contact times. [ABSTRACT FROM AUTHOR]

Pseudo-boehmite is prepared from industrial grade aluminum sulfate and sodium meta-aluminate coming from waste FCC catalysts. The effects of preparation technology， conditions and modification on crystal type， pore structure， surface acidity and morphology of pseudo-boehmites are investigated. The activity and selectivity of Pd/Al2O3 catalyst prepared by modified Al2O3 carrier and PdCl2 and Pd（acac）2 precursors for the selective hydrogenation of isoporone C==C are studied. The pseudo-boehmite with specific surface area of 413 m² /g， pore volume of 0. 84 cm3 /g and pore size of 6. 84 nm is obtained at the optimized preparation conditions. After the addition of ammonium carbonate and sodium silicate， the pore volume of pseudo-boehmite increases to 0. 98 cm³ /g and 1. 53 cm³/g， and the average pore size increases to 7. 70 nm and 12. 34 nm， respectively. The Pd/Al2O3 catalyst that is prepared using Al2O3 obtained by ammonium carbonate modifier as the carrier and PdCl2 as the precursor shows an activity of 98. 69% for the selective hydrogenation of isophorone C==C， more than 99% selectivity of 3,3, 5-trimethyl-cycloheeanon （TMCH), and high activity stability. [ABSTRACT FROM AUTHOR]

Natural kaolinite obtained from Share, Nigeria was treated with ammonium carbonate to enhance the adsorption capacity. The optimum operating conditions for the adsorption of metal ions on the natural clay (SK clay) were employed on the ammonium carbonate-treated clay (SK-AC clay). The adsorption data were analysed using adsorption isotherm and kinetic models. The statistical p-values were less than 0.05, indicating that the model terms are significant for the adsorption of the metal ions. The pseudo-second-order kinetic model best describes the metal ions adsorption mechanism. The activation energy values less than 40 kJ mol-1 obtained indicated physisorption. Langmuir adsorption isotherm model fitted the adsorption data for Fe2+, Zn2+ and Cr6+ ions while the Freundlich model fitted Pb2+ ions adsorption. Analysis of thermodynamic parameters shows the adsorption is spontaneous and endothermic. The ammonium carbonate-modified clay exhibited an increase in adsorption capacity from 10.74 to 13.60 mg g-1, 16.48 to 17.38 mg g-1 and 11. 96 to 13.8 mg g-1 for Fe2+, Pb2+ and Zn2+ ions while uptake of Cr6+ decreased from 8.75 to 7.25 mg g-1. The results showed that the adsorption of Fe2+, Pb2+ and Zn2+ ions onto kaolin-containing cowlesite can be enhanced by treating it with ammonium carbonate. [ABSTRACT FROM AUTHOR]

The electrochemical behavior of tungsten and a VNZhK alloy (wt %: 90 W, 7.2 Ni, 1.8 Fe, 1 Co) in 0.5–1.5 M solutions of ammonium carbonate is studied by linear voltammetry in the potentiodynamic mode. An increase in the maximum anodic current density for the oxidation of tungsten and VNZhK alloy with the ammonium carbonate concentration is revealed. The electrochemical dissolution of the VNZhK alloy wastes in a 1.0 M solution of ammonium carbonate is studied by galvanostatic electrolysis and electrolysis using sinusoidal industrial-frequency alternating current. The advantage of a step-by-step application of direct and alternating currents is substantiated. For the processing of the VNZhK alloy wastes under the step-by-step action of direct and alternating currents, the transition of tungsten from the alloy to an ammonium carbonate solution is accompanied by concentrating the iron-group metals in a microdispersed electrolysis slime. A principal technological scheme is proposed for tungsten recovery from the wastes of heavy tungsten alloys to form ammonium paratungstate as the final product. [ABSTRACT FROM AUTHOR]

Copyright of Power Generation Technology is the property of Power Generation Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We have studied the effect of the nature of the alkaline agent (NH4OH, NaOH, (NH4)2CO3, and Na2CO3) on the specific surface area, size, and shape of zinc oxide particles prepared via zinc nitrate precipitation from aqueous and polymer media, followed by thermal decomposition of the precipitates. The precipitation process with the use of NH4OH and NaOH in polyacrylamides has been shown to be favorable for the formation of large hexagon particles, which were larger (up to 1500 nm in size) in the case of NH4OH. The largest specific surface area (up to 98 m2/g) and the smallest particle size (~20 nm) were offered by the sample prepared via thermal decomposition of the products of reaction between zinc nitrate and ammonium carbonate. [ABSTRACT FROM AUTHOR]

Nano spinel LiNi0.5Mn1.5O4 is prepared from lithium nitrate, nickel nitrate and manganese nitrate by high-gravity co-precipitation reaction and microwave calcination, with ammonium carbonate as precipitant and ammonia as pH regulator. The effects of different preparation conditions on the structure and morphology of LiNi0.5Mn1.5O4 are investigated. The optimum preparation conditions are determined as follows: n(Li) : n(Ni) : n(Mn) is 1.05 : 0.5 : 1.5, total cation concentration is 0.24 mol/L, pH=8.0, rotor speed is 1 000 r/min, microwave calcination temperature is 850 °C, and calcination time is 2 h. The spinel LiNi05Mn15O4 prepared under this condition has high crystallinity, complete crystal form, fine and uniform particles with an average particle size of 65 nm, which provides a theoretical basis for further research on the electrochemical performance of nano spinel LiNi0.5Mn1.5O4 cathode materials. [ABSTRACT FROM AUTHOR]

The steam reforming of dimethyl ether (SRD) has been proved to be one of the most promising routes for on-site H2 production. However, the two-step consecutive nature of the SRD reaction makes the design of an efficient bifunctional catalyst a challenge. Herein, a series of Cu incorporated into amorphous silica–alumina (Cu–ASA) as integrated bifunctional catalysts for SRD were synthesized by the single-step complex decomposition method, and ammonium carbonate was confirmed to be an effective complex agent for dispersing Cu in ASA. The results indicated that the initial conversion of dimethyl ether and a H2 yield higher than 90% were achieved at 300 °C over the optimal catalyst. More importantly, a slightly decreased SRD performance with increasing time-on-stream was mainly caused by Cu sintering, and the synergetic effect between ASA and Cu played a crucial role in determining the activity, hydrogen yield, and stability of the integrated Cu–ASA bifunctional catalyst for SRD. These findings are helpful to develop a high-performance integrated bifunctional catalyst for the SRD reaction. [ABSTRACT FROM AUTHOR]

The decrease in the availability of high-quality bauxites makes the processing of high-silica raw materials inevitable, and in this regard, it is necessary to develop acid–salt methods suitable for these ores. The purpose of the work was to study various stages of the hydrosulfate method for processing alumina-containing raw materials on the example of nepheline concentrate in order to investigate the possibilities of their improvement. A. The distribution of various macro- and meso-components of leaching between phases at the stage of isolation of ammonium alum depending on sulfate concentration were experimentally and theoretically studied. It was shown that, with an increase in the total concentration of sulfate in the equilibrium mother liquor, the concentration of main impurity components, including iron, in a solid phase decreases significantly. To obtain relatively pure alum, it was recommended to use ammonium hydrosulfate with a concentration of at least 4 mol/L. B. Different embodiments for further purification of alum were explored. It was found that the use of the recrystallization process in the presence of small additions of sodium thiosulfate reduces the content of iron impurities in alum by almost an order of magnitude. C. A method for isolating purer final product was demonstrated. Isolation of ammonium aluminum carbonate hydroxide (ASACH), as a precursor of high-purity alumina, using ammonium bicarbonate is currently the most promising method in the hydrosulfate technology. In combination with the process of recrystallization, the preparation of AACH makes it possible to eliminate the need for expensive methods of selective sorption or extraction for deep purification of aqueous solutions of alum. [ABSTRACT FROM AUTHOR]

Lake Mariout is Egypt's degraded coastal marine habitat that encompasses a variety of wastes. The biodiversity and hard environmental conditions allow the co-existence of organisms with high resistance and rich metabolism, making them potential candidates for screening and isolating novel microbial strains. A bacterial isolate (BF202) cultured from the marine sediments of Alexandria's Mariout Lake (Egypt) was tested for its antimicrobial and anticancer potential. The phylogenetic analysis of the isolated strain's 16S rDNA and gyrB revealed that BF202 belongs to Brevibacillus laterosporus (B. laterosporus). Antibiosis of B. laterosporus was confirmed against microbial pathogens including Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, and Staphylococcus aureus. The highest antibacterial activity was detected on glucose peptone medium after 18 h of incubation at 35 °C, and at pH of 7.0 in the presence of mannose and ammonium carbonate as carbon and nitrogen sources, respectively. The cytotoxicity of the methanolic extract against breast cancer (MCF-7) and normal Vero cell lines, using the MTT test, revealed IC50 values of 7.93 and 23.79 µg/mL, respectively. To identify apoptotic and necrotic cells, a flow cytometric analysis using annexin V-FITC/PI dual-labeling was utilized and recorded a higher number of necrotic cells compared to apoptotic ones. Similarly, the cell cycle S-phase arrest was reported. The LC-MS-MS investigation of B. laterosporus extract and the molecular networking database analysis demonstrated five strategic diketopiperazine compounds with antimicrobial and anticancer activities. Taken together, this research shows that the crude extract of B. laterosporus might be an effective agent against drug-resistant bacteria and malignant disorders due to its richness in diketopiperazines. [ABSTRACT FROM AUTHOR]

Copyright of CE/Papers is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, amorphous silica-alumina composite (ASA) with varied compositions was synthesized via the complex-decomposition method with different complex agents. The XRD characterization revealed the amorphous nature of ASA composites regardless of the synthesis conditions. However, the acidity and the textural properties of ASA composites characterized by BET, Py-FTIR and NH 3 -TPD were significantly affected by the specific complex agent and amount, Si/Al molar ratio and calcination temperature. Among the investigated complex agents, the optimal amount of ammonium carbonate was the most efficient in tailoring both the textural and acidic properties of ASA. The hybrid of the synthesized ASA and a commercial Cu/ZnO/Al 2 O 3 was studied for the steam reforming of dimethyl ether (SRD), and ASA synthesized by using ammonium carbonate as the complexing agent showed the optimal activity. Importantly, the synergetic effect between ASA and Cu/ZnO/Al 2 O 3 was found to play a crucial role in determining the activity and stability of the bifunctional catalyst, and the partial oxidation of Cu0 to Cu+ induced from the ASA acidity had a great contribution to the deactivation of the bifunctional catalyst. These understandings are favorable for developing a more efficient solid acid for SRD. [Display omitted] • ASA was prepared by complex-decomposition method with different complexing agents. • ASA obtained with ammonium carbonate as complexing agent was more effective for SRD. • Over 80% DME conversion and H 2 yield were achieved at 300 ℃ over optimal catalyst. • ASA-induced Oxidation of Cu0 to Cu+ was one reason for deactivating SRD catalyst. [ABSTRACT FROM AUTHOR]