In this paper we present a synthesis method for obtaining hydroxyapatite nanopowders by chemical precipitation. As the starting reagents, analytical grade Ca(OH)2, H3PO4 and NH4OH were used. . In order to study the factors that have an important influence on the chemical precipitation process a experimental platform has been designed for hydroxyapatite synthesis. The experimental platform was d...

abstract aims: chemical precipitation is a simple, efficient, and cost-effective method for eliminating heavy metals found in landfill leachate. the aim of the present study was to compare the efficacy rates of cadmium removal with the coagulants like poly aluminum chloride and lime using chemical precipitation method. materials & methods: in this experimental study, the raw studied samples wer...

industrial development and extensive use of heavy metals have led to the problem of environmental pollution. nickel compounds are toxic to plants and have detrimental effects on their growth. valerian is a plant used in herbal medicine. considering the hazards of nickel, various methods have been developed to remove this contaminant from herbs irrigation wastewater, including the common chemica...

in this study, synthesis of copper nanoparticles and effect of the reaction conditions on the particle size were investigated. the copper nanoparticles were synthesized and stabilized in a narrow temperature range in the presence of polyvinylpyrrolidone under nitrogen atmosphere. reaction temperature and concentration ratio of the reducing agent to the precursor (r/p) as two main conditions i...

in order to reduce the operating temperature of solid oxide fuel cells (sofcs), novel electrolyte materials based on ceo2 and baceo3 are being developed in the scientific realm. in this context, we propose a new methodology for preparing the nano-ceramic composite materials such as bace0.9gd0.9o3-δ – ce0.9gd0.9o2-δ (bcgo–cgo) and bace0.8sm0.2o3-δ – ce0.8sm0.2o2-δ (bcso – cso) as possible elec...

To simulate the dynamic interaction between a saline lagoon and a ground water system, a numerical model for two-dimensional, variable-density, saturated-unsaturated, and coupled flow and solute transport (saltwater intrusion by finite elements and characteristics [SIFEC]) was modified to allow the volume of water and mass of salt in the lagoon to vary with each time step. The modified SIFEC al...

Background: Mature landfill leachate is a complicated mixture which is resistant to biological treatment processes. The treatment of mature landfill leachate by struvite precipitation and Fenton oxidation was the main objective of the current research. Methods: Struvite with the phosphate/ammonia/magnesium molar ratio of 1/1/1.05 was considered during all experiments. Five initial pHs of 3, 4, ...

a set of multicomponent perovskite oxide nanoparticles based on la1-xsrxco1-yfeyo3-δ(lscf) were prepared by a simple chemical precipitation method for application in low temperature solid oxide fuel cells (lt-sofc) as cathode materials.  the precursor materials used in this synthesis were lanthanum nitrate hexahydrate [la(no3)3.6h2o], strontium nitrate [sr(no3)2], cobalt nitrate hexahydrate [co...

background: mature landfill leachate is a complicated mixture which is resistant to biological treatment processes. the treatment of mature landfill leachate by struvite precipitation and fenton oxidation was the main objective of the current research. methods: struvite with the phosphate/ammonia/magnesium molar ratio of 1/1/1.05 was considered during all experiments. five initial phs of 3, 4, ...

Chemical gardens are mineral aggregates that grow in three dimensions with plant-like forms and share properties with self-assembled structures like nanoscale tubes, brinicles, or chimneys at hydrothermal vents. The analysis of their shapes remains a challenge, as their growth is influenced by osmosis, buoyancy, and reaction-diffusion processes. Here we show that chemical gardens grown by injec...