Concentrations Of Ammonium Chloride Research Articles

Leaching kinetics of zinc silicate in ammonium chloride solution

The leaching kinetics of zinc silicate in ammonium chloride solution was investigated. The effects of stirring speed (150–400 r/min), leaching temperature (95–108 °C), particle size of zinc silicate (61–150 μm) and the concentration of ammonium chloride (3.5–5.5 mol/L) on leaching rate of zinc were studied. The results show that decreasing the particle size of zinc silicate and increasing the leaching temperature and concentration of ammonium chloride can obviously enhance the leaching rate of zinc. Among the kinetic models of the porous solids tested, the grain model with porous diffusion control can well describe the zinc leaching kinetics. The apparent activation energy of the leaching reaction is 161.26 kJ/mol and the reaction order with respect to ammonium chloride is 3.5.

Modification of steel surface by plasma electrolytic saturation with nitrogen and carbon

The effect of the electrolyte composition with ammonia, acetone, and ammonium chloride on the structure and properties of low carbon steel was studied in anode plasma electrolytic nitrocarburising. An X-ray diffractometer, a scanning electron microscopy (SEM) and an optical microscope were used to characterize the phase composition of the modified layer and its surface morphology. Surface roughness was studied with a profilometer–profilograph. The hardness of the treated and untreated samples was measured using a microhardness tester. The sources of nitrogen and carbon are shown to be the products of evaporation and thermal decomposition of the electrolyte components. It is established that the influence of concentration of ammonia, acetone, and ammonium chloride on the size of the structural components of the hardened layer is explained by the competition of the anode dissolution, high-temperature oxidation and diffusion of the saturating component. The electrolyte composition (10–12.5% ammonium chloride, 5% acetone, 5% ammonia) and processing mode (800 °C, 5–10 min) of low carbon steels allowing to obtain the hardened surface layer up to 0.2 mm with microhardness 930 HV and with decrease in the roughness (Ra) from 1.013 to 0.054 μm are proposed. The anode plasma electrolytic nitricarburising is able to decrease friction coefficient of the treated low carbon steel from 0.191 to 0.169 and wear rate from 13.5 mg to 1.0 mg.

Removal of cobalt from ammonium chloride solutions using a batch cell through an electrogenerative process

Studies of the removal of cobalt were carried out in a batch cell via an electrogenerative system. Use of electrogenerative systems had successfully demonstrated the feasibility of recovery of co-ions simultaneously. Studies of removal of cobalt from chloride solutions were accomplished using ammonium chloride as a supporting electrolyte. The influence of catholyte and supporting electrolyte concentrations on cobalt recovery were studied by varying the initial cobalt concentrations and ammonium chloride concentration respectively. The results showed that 0.50 M of ammonium chloride was the optimum concentration with <95% of cobalt being removed from an initial Co(II) concentration of 200 mg L−1 in 4 h of operation. A high free energy of −403.89 kJ mole−1 was generated in the electrogenerative process. Cell performance of 85.6% with 100% cobalt recovery was obtained from 200 mg L−1 of Co2+ in 0.5 M NH4Cl. The influence of pH adjustment was examined at pH 7. The morphology of cobalt deposited was also observed by scanning electron microscopy.

Improved growth performance of Gracilariopsis heteroclada via short-term nitrogen enrichment

Abstract This study examined the effect of short-term nitrogen (N) enrichment on Gracilariopsis heteroclada growth and agar quality. Planting materials were soaked in different concentrations of ammonium chloride (NH4Cl) for 6 h. Total thallus N content was highest in Gp. heteroclada enriched in 300 mg l-1 NH4Cl. Growth experiments showed that this enrichment treatment (300 mg l-1 NH4Cl for 6 h) increased the growth of Gp. heteroclada (4.22±0.09% day-1) compared with the control (3.68±0.12% day-1). Pond culture using enriched Gp. heteroclada resulted in high growth rates (6.14±0.50% day-1). No epiphyte growth was observed during either the growth experiment or the pond culture. There were no significant differences between the agar yields of the enriched (3.65±0.36%) or control (3.78±0.18%) Gp. heteroclada. Additionally, no significant differences were detected when the gel strength of the enriched (611±22 g cm-2) and control (587±11 g cm-2) Gp. heteroclada were compared. The results suggest that the short-term N enrichment method could be an alternative culture strategy to increase Gp. heteroclada production and lower farming costs.

Structural and Ionic Conductivity Studies of CMC Based Polymerelectrolyte Doped with NH4Cl

The present study aims to investigate the structural and ionic conductivity of carboxymethyl cellulose - ammonium chloride as proton conducting polymer electrolytes. The complexion of polymer electrolyte films has been confirmed via FTIR studies. The conductivity enhancement with the addition of ammonium chloride concentration was proved due to the increase in amorphous nature of the films as evidenced by XRD analysis. Impedance studies indicate that the highest ionic conductivity of 1.43 x 10-3Scm-1was observed with the addition of 16 wt.% ammonium chloride in polymer electrolyte system obtained at ambient temperature.

Origins of the Intermediate Spectral Form in M100 Mutants of Photoactive Yellow Protein.

Numerous single-site mutants of photoactive yellow protein (PYP) from Halorhodospira halophila and as well as PYP homologs from other species exhibit a shoulder on the short wavelength side of the absorbance maximum in their dark-adapted states. The structural basis for the occurrence of this shoulder, called the "intermediate spectral form," has only been investigated in detail for the Y42F mutation. Here we explore the structural basis for occurrence of the intermediate spectral form in a M121E derivative of a circularly permuted H.halophila PYP (M121E-cPYP). The M121 site in M121E-cPYP corresponds to the M100 site in wild-type H.halophila PYP. High-resolution NMR measurements with a salt-tolerant cryoprobe enabled identification of those residues directly affected by increasing concentrations of ammonium chloride, a salt that greatly enhances the fraction of the intermediate spectra form. Residues in the surface loop containing the M121E (M100E) mutation were found to be affected by ammonium chloride as well as a discrete set of residues that link this surface loop to the buried hydroxyl group of the chromophore via a hydrogen bond network. Localized changes in the conformational dynamics of a surface loop can thereby produce structural rearrangements near the buried hydroxyl group chromophore while leaving the large majority of residues in the protein unaffected.

The accelerating effect of a small cationic quaternary ammonium compound and the adsorption kinetics in the dyeing of silk with reactive dyes

In order to develop an eco‐friendly method for silk reactive dyeing that uses a lower accelerant dosage to achieve a higher dye fixation, hexyl dimethyl octyl ammonium chloride was synthesised as an accelerant for the dyeing of silk with reactive dyes. The accelerating effect, corresponding adsorption kinetics, and interaction mechanisms among hexyl dimethyl octyl ammonium chloride, reactive dyes, and silk were investigated. At hexyl dimethyl octyl ammonium chloride concentrations of 10.8–14.4 mm, the dye fixations for three reactive dyes were much higher than those achieved with sodium sulfate, even though the required dosages of hexyl dimethyl octyl ammonium chloride were 30–40 times lower than those of sodium sulfate. The wash fastness, rub fastness, light fastness, K/S, and colour difference values after dyeing with hexyl dimethyl octyl ammonium chloride were similar to those obtained using sodium sulfate, and silk can be dyed uniformly. The adsorption kinetics followed a second‐order kinetic model. The activation energies of surface adsorption for the three reactive dyes were lower than those of sodium sulfate. The high fixation of reactive dyestuffs and the low required dosage of hexyl dimethyl octyl ammonium chloride demonstrate that the use of this new accelerant provides a novel, highly efficient method for silk dyeing. A possible acceleration mechanism of hexyl dimethyl octyl ammonium chloride for reactive dyes adsorbed on the surface of silk was proposed, based on a series of activation parameters of the adsorption process.

Features of anode plasma electrolytic nitrocarburising of low carbon steel

The influence of the electrolyte composition with carbamide and ammonium chloride on the structure of low carbon steel was investigated in anode plasma electrolytic nitrocarburising (PEN/C). An X-ray diffractometer, a scanning electron microscopy (SEM) and an optical microscope were used to characterize the phase composition of the modified layer and its surface morphology. Surface roughness and topology were studied with the use of a profilometer–profilograph and an atomic force microscope. The hardness of the treated and untreated samples was measured using a microhardness tester. Carbamide is demonstrated to decompose via isocyanic acid with result of ammonia and carbon monoxide as carbon and nitrogen donors. It is established that the influence of concentration of ammonium chloride and carbamide on the size of the structural components of the hardened layer is explained by the competition of the anode dissolution, high-temperature oxidation and diffusion of the saturating component. The electrolyte composition (10–15% ammonium chloride, 15% carbamide) and processing mode (850–950°C, 5min) of low carbon steels allowing one to obtain the hardened surface layer up to 0.2mm with microhardness 740HV and with decrease in the roughness of 9 times are proposed. The anode plasma electrolytic nitricarburising could decrease friction coefficient and increase wear resistance of the low carbon steel.

The Effects of Temperature and Nutritional Conditions on Mycelium Growth of Two Oyster Mushrooms (Pleurotus ostreatus and Pleurotus cystidiosus)

The influences of temperature and nutritional conditions on the mycelium growth of oyster mushroom Pleurotus ostreatus (PO) and Pleurotus cystidiosus (PC) were investigated in laboratory experiment during the summer season of 2014. The results of the experiment indicated that potato dextrose agar (PDA) and yam dextrose agar (YDA) were the most suitable media for the mycelium growth of oyster mushroom PO while four media (PDA, YDA, sweet potato dextrose agar, and malt extract agar medium) were not significantly different in supporting mycelium growth of oyster mushroom PC. The optimal temperature for mycelium growth of both oyster mushroom species was obtained at 28°C. Mycelium growth of oyster mushroom PO was improved by carbon sources such as glucose, molasses, and at 1~5% sucrose concentration, mycelium colony diameter of mushroom PO was achieved the highest value. Whereas glucose, dextrose, and sucrose as carbon sources gave the good mycelium growth of oyster mushroom PC, and at 1~3% sucrose concentration, mycelium colony diameter of PC was achieved the maximum value. Ammonium chloride concentrations at 0.03~0.09% and 0.03~0.05% also gave the greatest values in mycelium colony diameter of mushroom PO and PC. Brown rice was found to be the most favourable for mycelium growth of two oyster mushroom species. In addition, sugarcane residue, acasia sawdust and corn cob were selected as favourable lignocellulosic substrate sources for mycelium growth of both oyster mushrooms.

Plasma electrolytic modification of the VT1-0 titanium alloy surface

The features of the anodic plasma electrolytic treatment of commercial titanium in an aqueous ammonium chloride solution with ammonia and glycerol additions are investigated. It is revealed that the modified layer comprises an external TiO2 or TiO layer with micropores of up to 100 nm and a diffusion sublayer after nitriding in the solution with the ammonia addition. It is ascertained that the anodic dissolution of the titanium alloy dominates over its oxidation at treatment voltages reaching 210 V and an ammonium chloride concentration of 100 g/L. This effect is accompanied by a decrease in the sample mass. The sample mass grows due to an increase in the oxide layer exceeding the dissolution losses at higher voltages and ammonium chloride concentrations. It is shown that the corrosion current density in Ringer’s solution can be decreased after commercial titanium is treated in the ammonium chloride and glycerol solution.

Experimental Investigation of Poly-β-Hydroxybutyrate Production by Azohydromonas lata: Kinetics and Artificial Neural Network Modeling

Batch culture of Azohydromonas lata was investigated for the production of intracellular poly-β-hydroxybutyrate (PHB). In order to determine the C:N value of the culture media for maximizing the microbial productivity of PHB, different concentrations of glucose and ammonium chloride were used as carbon and nitrogen sources, respectively. The optimal temperature and shaking rate was obtained at 30°C and 180 rpm, respectively. The maximum intracellular PHB concentration obtained was 5.09 g/l, which was 20% (w/w) of the cell dry weight (CDW) after 72 h. Also, the synthesis of PHB was growth associated with the C:N ratio of 153.71. The maximum calculated Yp/s was 0.212 (gr/gr) and the specific production rate value after 12 h was 0.264 g/l/h, with 40 and 50 g/l of glucose concentrations, respectively, with 0.5 g/l ammonium chloride kept constant. The chemical composition of the resulting PHB was analyzed by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy. The Leudeking–Piret model was used for kinetic analysis of the PHB production, the statistical analysis of which was modeled by response surface methodology. An artificial neural network technique was applied for modeling of the microbial production of PHB by A. lata as a function of the glucose concentration and CDW, where the minimum mean square error of the model was 0.0012 and 0.0038 for glucose concentrations of 50 g/l and 40 g/l, respectively, when 0.5 g/l ammonium chloride was kept constant.

The Leaching of Copper Oxide Ore in Ammonium Chloride Solution

In this study, the leaching effect of copper oxide ore was investigated using ammonium chloride solution as leaching agent. The effects of temperature, concentration of ammonium chloride, average particle size and stirring speed on the leaching of copper oxide ore were investigated. The leaching rate increased with increasing solution temperature, concentration, and stirring speed as well as with decreasing average particle size. Ammonium chloride solution can therefore be used as an effective leaching agent for copper extraction from copper oxide ore.

Enhanced Bioremediation of Field Agricultural Soils Contaminated with PAHs and OCPs

Effect of different concentrations of ammonium chloride (NCL) and ammonium nitrate (NN)and surfactants such as Tween-80, HPCD and rhamnolipids on the bioremediation of PAHs and OCPs wasinvestigated. The results showed that the best optimum concentration of NCL and NN was 50 g·kg-1, and thePAHs degradation rate during 60 days of remediation was enhanced to 64.6% and 62.8% for NCL and NN,respectively, which was approximately 45, 17, 10% higher than those in the control group, soil only addedmicroorganism, soil added microorganism and tourmaline. OCP removal rates were 51.7% and 50.4 % for NCLand NN, respectively, which was 34% higher than the control group, 14% higher than the soil only addedmicroorganism, 9% higher than the soil added microorganism and tourmaline. The best dose of Tween-80,HPCD and rhamnolipids was 2, 0.5 and 0.2 g·kg-1. When they were applied, the PAHs degradation rate during60 days of remediation was enhanced to 69, 70.4 and 71.5%, respectively, which was approximately 52, 24and 17% than those in the control group, soil only added microorganism, soil added microorganism andtourmaline. Similarly, OCP removal rate was 42, 26 and 16% higher than those in the control group,microorganism -added soil alone, soil added microorganism and tourmaline. Additionally, nutrients and surfactantscan promote the generation of soil hydrogen peroxidase and invertase enzyme. Hence, the present studyprovides a promising combination remediation technology for the remediation of field soils contaminated byPAHs and OCPs.

Indirect Carbonation of Victorian Brown Coal Fly Ash for CO2 Sequestration: Multiple-Cycle Leaching-Carbonation and Magnesium Leaching Kinetic Modeling

In this paper, a closed-loop multistep process which allows leaching and precipitation of magnesium and calcium as carbonate from Victorian brown coal fly ash has been examined. Victorian brown coal fly ash has a distinctively high concentration of alkaline earth metals and low amounts of aluminum and silica. The main objective here is to clarify the dissolution kinetics of magnesium and calcium in regenerative ammonium chloride and subsequent carbonation of dissolved cations. Instead of a once-through test with fresh ammonium chloride, multiple locked circuits were adopted to assess the leaching capability of regenerated ammonium salt, as well as the accumulation of impurities upon the recycling and reuse of the leaching agent. As has been revealed, upon increasing cycles of ammonium chloride use, the extraction yields of both target cations decreased significantly. Their extraction by ammonium chloride was favored by the presence of the oxide form in the original ash sample, with the extraction of calcium occurring much faster than that of magnesium. Both phenomena were in agreement with the thermodynamic equilibrium prediction on the lowest Gibbs function for the dissolution of oxides, especially calcium oxide in ammonium chloride solution. Carbonation results dropped gradually upon the increase in the cycle number; meanwhile, the size and morphology of precipitates were changed from the first to last cycle. By fitting the observed results with a shrinking core model, it was shown that the extraction of Mg2+ followed a pseudo-second-order reaction with a nonconstant ammonium chloride concentration in the film layer on the surface of a solid particle. The activation energy of 20.7 kJ mol–1 was obtained for the dissolution of magnesium from both Hazelwood fly ash and pure MgO in ammonium chloride solution.

Liquid–liquid equilibrium of 1-butanol + water + tri-n-butyl phosphate + ammonium chloride system

In this paper, the liquid–liquid equilibrium (LLE) and tie-line data of the system containing 1-butanol+water+tri-n-butyl phosphate (TBP)+ammonium chloride have been studied at 298.15, 308.15 and 318.15K under atmospheric pressure. The influence of temperature and different concentrations of ammonium chloride have been investigated. In addition, nonrandom two-liquid (NRTL) model is applied to the system, and the relevant interaction parameters are regressed with the experimental data. The quality of the correlation is measured by the rmsd (rmsd≤0.0131). The results show that the calculated values by NRTL model are in agreement with the determination of LLE data of the studied system in the investigated conditions.

Dissolution Kinetics of Magnesium from Calcined Serpentine in NH4Cl Solution

A process of extracting magnesium from serpentine to produce Mg compounds by using recyclable NH3 was proposed. This process includes calcination of serpentine; dissolution of magnesium by NH4Cl leaching to obtain NH3 and MgCl2-rich solution, and precipitation of Mg(OH)2 from refined MgCl2-rich solution by feeding NH3. The effects of various factors, such as roasting temperature and time, particle size, concentration of NH4Cl solution, solid-to-liquid ratio, and leaching temperature, on the dissolution kinetics of magnesium of the calcined serpentine were comprehensively investigated. It is found that the extraction rate of magnesium was enhanced by the removal of NH3 generated from the reaction system. Thus, the obtained optimum conditions for magnesium extraction from serpentine are a roasting temperature of 700 °C, a roasting time of 1 h, a particle size fraction of −0.20 + 0.10 mm, an initial ammonium chloride concentration of 4.0 M, a solid-to-liquid ratio of 20/500 g/mL, and a reaction temperature of 104 °C. With the removal of NH3 in batch leaching study, the maximum recovery of magnesium reached 83.87%, and the concentration of magnesium was ∼0.63 mol·L–1, satisfying the requirement of Mg(OH)2 precipitation. Finally, the reaction kinetics of the system was successfully modeled by an empirical diffusion-like equation. The apparent activity energy was obtained to be 23.56 ± 1.06 kJ·mol–1. The results from this study provide the fundamentals for magnesium extraction from serpentine by NH4Cl leaching.

Discovery of proteins in Acanthamoeba polyphaga with potential as biomarker for ammonium chlroride contamination

IntroductionSeveral stressed proteins expressed by live cells have been recognised as biomarker especially those related to certain implications in human's health. Other stressed proteins observed in other cells such as in free-living amoebae isolated from polluted water can be biomarker candidates for environmental health. In the present study, Acanthamoeba poyphaga CCAP 1501/3A was exposed to various concentrations of ammonium chloride as example of pollutants in our environment. The expression of proteins in this amoeba was analysed and the potential biomarker was identified. ObjectiveTo analyse and identify proteins in Acanthamoeba polyphaga as biomarker for ammonium chloride contamination Methods2-D electrophoresis was employed to analyse protein profile in Acanthamoeba polyphaga (CCAP 1501/3A) after the amoeba was exposed for 72 h at various concentrations (ranging from 0.5mg to 3.0 mg) of the ammonium chloride. Pellets of amoebae were collected by centrifugation and were then sonicated and centrifuged to obtain protein samples from the amoeba. A supernatant part (protein sample) from treated and control amoebae was subjected to 2D electrophoresis. A control gel was used as a reference/master gel when protein profiles in treated amoebae were analysed using ImageMaster 2DPlatinum. The potential biomarker (protein dots/peptides) in Acanthamoeba were analysed by MALDITOF-TOF mass spectrometer using a 5800 Proteomics Analyzer [AB Sciex]. Spectra were analysed to identify protein of interest using Mascot sequence matching software [Matrix Science] with Ludwig NR Database. Results & DiscussionThree protein dots were identified and analysed in Acanthamoeba as potential biomarker for ammonium chloride contamination. The expression of these proteins in ammonium-treated amoeba was dose-dependant, and was categorized as either under expressed, over expressed or a new protein. These proteins, therefore are suitable candidates as biomarkers in amoebae for ammonium chloride contamination in the aquatic ecosystem. ConclusionThree proteins observed in Acanthamoeba polyphaga (CCAP 1501/3A) are potential biomarkers for ammonium chloride contamination in the environment.

Production of Citric Acid by Candida lipolytica under Fermentation Conditions Using a Plackett-Burman Design

Citric acid is one of the most versatile industrial organic acids that are used in food industries, cosmetics and pharmaceuticals products. This work aimed to produce citric acid by Candida lipolytica under submerged fermentation conditions using a Plackett-Burman design. Twelve factors including pH, concentration of sodium acetate, magnesium sulfate, Ammonium chloride, potassium phosphate, ferric sulfate, manganese sulfate, zinc sulfate, yeast extract, glucose, aeration ratio and incubation time at a temperature of 30°C were tested as main variables affecting citric acid production using Plackett-Burman design. The results indicated that pH (7), concentration of sodium acetate (10g/L), magnesium sulfate (1.5g/L), potassium phosphate (5g/L), ammonium chloride (3g/L), ferric sulfate(140mg/L), manganese sulfate (50 mg/L), zinc sulfate (80 mg/L), yeast extract (5g/L), glucose (150g/L), aeration ratio(75ml medium/ flask250ml) and incubation period of 7 days were the most effective factors for the highest yield of citric acid production. The highest citric acid concentration was 22.8 g/L of the medium under the previously mentioned conditions.

Determination of the Optimum Conditions for Leaching of Zinc Cathode Melting Furnace Slag in Ammonium Chloride Media

This research is part of a continuing effort to leach zinc from zinc cathode melting furnace slags (ZCMFSs) to produce zinc oxide. The slag with an assay of 68.05 pct Zn was used in ammonium chloride leaching for zinc extraction. In this paper, the effects of influential factors on extraction efficiency of Zn from a ZCMFS were investigated. The Taguchi’s method based on orthogonal array (OA) design has been used to arrange the experimental runs in order to maximize zinc extraction from a slag. The softwares named Excel and Design-Expert 7 have been used to design experiments and subsequent analysis. OA L25 (55) consisting of five parameters, each with five levels, was employed to evaluate the effects of reaction time (t = 10, 30, 50, 70, 90 minutes), reaction temperature [T = 313, 323, 333, 343, 353 (40, 50, 60, 70, 80) K (°C)], pulp density (S/L = 20, 40, 60, 80, 100 g/L), stirring speed (R = 300, 400, 500, 600, 700 rpm), and ammonium chloride concentration (C = 10, 15, 20, 25, 30 pctwt), on zinc extraction percent. Statistical analysis, ANOVA, was also employed to determine the relationship between experimental conditions and yield levels. The results showed that the significant parameters affecting leaching of slag were ammonium chloride concentration and pulp density, and increasing pulp density reduced leaching efficiency of zinc. However, increasing ammonium chloride concentration promoted the extraction of zinc. The optimum conditions for this study were found to be t4: 70 minutes, T5: 353 K (80 °C), (S/L)2: 40 g/L, R3: 500 rpm, and C4: 25 pctwt. Under these conditions, the dissolution percentage of Zn in ammonium chloride media was 94.61 pct.

Experimental renal calcium oxalate calculus models without severe renal damage in rats

Objective To screen a short-term,economical and satisfied model of renal calcium oxalate calculus in rats with minimal renal damage.Methods Ninety male Sprague-Dawley (SD) rats were randomly divided into two groups.In group 1,the rats were treated with 1.0％ ammonium chloride and different concentrations of ethylene glycol (0.1％,0.2％,0.4％ and 0.8％).In group 2,the rats were treated with different concentrations of ethylene glycol (0.1％,0.2％,0.4％ and 0.8％).The body mass change,the serum creatinine and urine creatinine,and urinary oxalate excretion were measured.Conventional HE dyeing was carried out for kidney tissues and pathological changes,and the status of kidney stone formation was further observed.Results In group 1 treated with 1.0％ ammonium chloride and 0.1％ ethylene glycol for 7 days,the urinary oxalate excretion days was significantly higher than in control group (P ＜0.05).In group 1 treated with 0.4％ or 0.8％ ethylene glycol + 1.0％ ammonium chloride for 14 days,the creatinine clearance was lower than in control group (P ＜ 0.01).Light microscopy showed that calcium oxalate crystals formed in renal cortex,medulla and renal papilla,and inflammatory damage of renal tissue was aggravated.In group 2 treated with 0.4％ or 0.8％ ethylene glycol for 7 days,the urine oxalate excretion was higher than in control group (P ＜0.01),however,there was no statistically significant difference in the creatinine clearance (P ＞ 0.05).Light microscopy showed no obvious interstitial edema in renal cortex and a small amount of stone crystals were seen with no inflammatory cells infiltration.Conclusion Ethylene glycol alone is a quich,economic and good calcium oxalate crystallized method in rats without severe renal damage. Key words: Urolithiasis ; Calcium oxalate ; Ethylene glycol; Model,animal