Showing papers on "Distilled water published in 2010"

Ultrasound-Assisted Osmotic Dehydration of Strawberries: Effect of Pretreatment Time and Ultrasonic Frequency

Abstract: Pretreatment of fruits prior to drying has shown success in reducing drying time and costs. In this work, ultrasound-assisted osmotic dehydration has been implemented as a method to increase water diffusivity and reduce drying time in strawberries. Strawberry halves were immersed in distilled water and in two different concentrations of sucrose solutions while pretreatment time and ultrasonic frequency levels were varied to determine their effect on drying time, water loss, and soluble solids gain. A microscopic analysis was carried out to evaluate the formation of microchannels and other changes to the fruit tissue structure. Greater sucrose concentration used in ultrasound-assisted osmotic dehydration resulted in greater water loss with greatest loss observed for the strawberry halves pretreated for 45 min in a 50% w/w sucrose solution. The pretreatment carried out for 30 min employing an osmotic solution of 50% w/w of sucrose resulted in the highest drying rate among the pretreatments. Osmotic dehydrat...

Detection of ions released from S-PRG fillers and their modulation effect.

Abstract: The purpose of this study was to analyze the ions released from a surface pre-reacted glass ionomer (S-PRG) filler in distilled water or lactic acid solution. S-PRG filler was mixed with either solution at 1000:1, 100:1, 10:1, and 1:1 ratios by weight. By means of inductively coupled plasma atomic emission spectroscopy and a fluoride electrode, elements released from S-PRG filler were identified to be Al, B, Na, Si, Sr, and F. To investigate the effect of solution pH on ion release, the pH values of the solutions before mixing and after 24 hours' mixing with S-PRG were measured. After 24 hours' mixing, the pH values of solutions at all ratios became more neutral or weakly alkaline regardless of their initial pH levels before mixing. In conclusion, results showed that S-PRG filler released several types of ions, and that ion release was influenced by the mixing ratio of the solution rather than the initial pH of the solution.

EFFECT OF SEED PRIMING DURATION AND TEMPERATURE ON SEED GERMINATION BEHAVIOR OF BREAD WHEAT (Triticum aestivum L.)

Abstract: In order to evaluate the effect of different seed priming techniques on germination and early growth of two wheat cultivars (Azar-2 and Sardari 101) an experiment was conducted at the Seed and Plant Certification and Registration Research Institute, Karaj, Iran. Seeds were primed for 12, 24 and 36 hours at three temperature (20, 23 and 28°C) in seven priming media (Poly ethylene glycol (PEG6000) 10%, PEG 20%, KCl 2%, KCl 4%, KH2PO4 0.5%, KH2PO4 1% and distilled water as control). Maximum seed germination percentage in cv.Azar-2 was observed when the seeds primed by PEG 20% for 12h and at 20°C. The most stem length was obtained for seeds osmoprimed with PEG 10% for 24h. Osmoprimed seeds with PEG 20% for 24h produced maximum radicle length of cv. Sardari. Maximum vigor index (VI) of cv. Azar-2 was obtained from seeds primed with KH2PO4 0.5% while the lowest germination percent, speed of germination and VI were observed in seeds which subjected to KCl 4% solution. Speed of germination was improved when the seed soaked water and PEG 10%. The most germination percent, VI and speed of germination were observed on 12h. Altogether 20°C treatment had better effects than other temperatures on germination attributes and seedling parameters. None of the interaction between seed priming media × cultivar × temperature and seed priming media × cultivar × priming duration showed the beneficial effects on germination index, speed of germination, dry weight and seedling height.

Long-Term Study on Tenacity of Avian Influenza Viruses in Water (Distilled Water, Normal Saline, and Surface Water) at Different Temperatures

Abstract: The tenacity of three low pathogenicity avian influenza viruses (AIV; subtypes H4N6, H5N1, and H6N8) was tested at five different temperatures (−10, 0, 10, 20, and 30 C) in distilled water, normal saline, and surface water obtained from Lake Constance. Infectivity of AIV in the samples was quantified at regular intervals by end point titration on Madin-Darby canine kidney cells for a maximum period of 36 wk, and duplicate samples were tested each time. The results showed that the survival time of AIV in all of the water types was inversely proportional to storage temperature. All three viruses showed varying sensitivity to inactivation under each of the experimental conditions. Persistence of the viruses was the longest in distilled water, second longest in normal saline, and shortest in surface water. The virus-inoculated surface water remained infective for a few days at 30 and 20 C, a few weeks at 10 C, and for months at 0 and −10 C.

Studies on water absorption of bamboo‐epoxy composites: Effect of silane treatment of mercerized bamboo

Abstract: The effect of silane treatment on the water absorption properties of bamboo matting reinforced epoxy composites were investigated. Experiments using γ-aminopropyltriethoxy silane, 3-trimethoxysilylpropylmethacrylate, vinyltris(2-methoxyethoxy)silane, bis[3-(triethoxysilyl)propyl]tetrasulfide, 3-aminopropyltrimethoxysilane, and n-octyltrimethoxysilane were carried out to improve the water resistant property of the bamboo fiber composites. Water absorption in the composites was studied by long term immersion and 2 h boiling in distilled water. The process of absorption of water was found to follow the kinetics and mechanism described by Fick's theory. Alkali treatment results in reduction of water absorption from 41 to 26%. Further reduction is observed with silane treatment. Water absorption varies between 21 and 24%, minimum being for aminopropyltriethoxysilane treated composite. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Enhancement of plant essential oils' aqueous solubility and stability using alpha and beta cyclodextrin.

Abstract: Sodium benzoate has been shown to produce benzene in combination with ascorbic acid. This has led to research for safe alternatives from plant essential oils and parabens that have shown some antimicrobial activity, but many of these compounds exhibit poor solubility in aqueous solutions. Cyclodextrins can increase the solubility of many compounds. This work aimed to investigate the solubility of 23 plant essential oils and 4 parabens in water and an apple juice medium. Four of these compounds were chosen for their low aqueous solubility to determine if complexing the compound with α- and β-cyclodextrin would increase solubility. Three of the complexes were dissolved in an acidified aqueous solution and then studied in glass and polyethylene terephthalate (PET) to determine if storage material would affect the stability. Solubility of the 27 compounds in distilled water ranged from 1.6 mg/L to 2460.6 mg/L and the solubility of 18 of the compounds decreased from 2.5 to 84.7% in apple juice medium (pH = 3.4, 12-13 °Brix). Complexation with cyclodextrin dramatically increased the solubility of the compounds, up to 10-fold. Packaging material had no effect on concentration of compounds present over 7 days. Cyclodextrins were able to increase solubility of these compounds to more suitable concentrations, and may lead to viable natural alternatives to sodium benzoate.

Nanoparticle–Nanorod Core–Shell LiNi0.5Mn1.5O4 Spinel Cathodes with High Energy Density for Li-Ion Batteries

Abstract: with distilled water and was vacuum-dried at 120°C. An as-prepared MnO2 template was used to prepare LiNi0.5Mn1.5O4, and appropriate amounts of LiC2H3O2·H2O and NiNO32·6H2O were completely dissolved in distilled water and mixed with MnO2 in a molar ratio of 1:0.5:1.5 LiC2H3O2·H2O:NiNO32·6H2O:MnO2. After drying it in an oven, the product was ground using mortar and pestle, fol- lowed by firing at 400 and 700°C for 2 and 8 h, respectively. For comparison, the cathode powder was obtained using the sol-gel pro- cess, LiC2H3O2·H2O was first dissolved in distilled water, and then MnC2H3O2·4H2O and NiNO32·6H2O were continuously dissolved into it with a molar ratio of 1:1.5:0.5 Li:Mn:Ni. Finally, poly vinylpyrrolidene as a chelating agent was mixed together, and NH4OH was added to adjust pH 8.5 to 9.0. The solution was dried at

Effect of reactor surface on production of bacterial cellulose and water soluble oligosaccharides by Gluconacetobacter hansenii PJK

Abstract: The effect of agar plates on the bacterial cellulose (BC) production in a static culture was investigated in order to find the role of agar component as a surface modifying agent. Two types of surface modified reactors (SMRs: SMRD and SMRB) were prepared by coating the bottom of the reactors with agar dissolved in distilled water and basal medium, respectively. The SMRs were used for BC and water soluble oligosaccharides (WSOS) production. Control was done by the same procedure using reactors without agar plate. In both types of SMRs, the maximum production rate was observed after the second day of cultivation compared to third day of cultivation in the case of the control. The maximum productions of BC 5.308 and 5.472 g/L were observed at the first batch using SMRs prepared with agar dissolved in distilled water (SMRDs) and SMRs prepared with agar dissolved in a basal medium (SMRBs), respectively. Similarly, in the daily-culture and successive batch strategy experiments the maximum amount of WSOS produced in the SMRs was almost double that of the control. The highest water holding capacity value 92.21 g/g was observed for BC formed in the SMRs prepared with 3.0% of agar. FTIR and XRD analyses were carried out to study the structural features of the prepared BC.

Effect of water chemistry on calcium carbonate deposition on metal and polymer surfaces

Abstract: The formation of calcium carbonate on the surfaces of polypropylene and copper tubes was studied by exposing tubes to a laminar flow of room temperature distilled water, supersaturated with respect to calcite. Three water chemistries were used: a control (pH 9.3), one with lower supersaturation but similar pH as the control, and one with higher pH (pH 11) but similar supersaturation as the control. The accumulation of calcium carbonate with time was characterized along with the microstructure and the crystal structure of the deposits. On both tube materials, the amount of calcium carbonate deposited per unit surface area increased with time. At any given time, the accumulation was significantly less when the low supersaturation water was used. For all three water chemistries, more calcium carbonate formed on polyproplyene as compared with copper, with the greatest difference between the two noted for the higher pH water. The deposits consisted of discrete particles and particle clusters, the number and size of which increased with time. Calcite was the dominant polymorph for deposits on copper. On polyproplyene, the deposits were a mixture of calcite, vaterite and aragonite with aragonite dominating except at low supersaturation. A simple model for the mass accumulation of particulate-based deposits with time is presented and the factors responsible for the differences between materials are discussed.

Food treatment with high pressure carbon dioxide: Saccharomyces cerevisiae inactivation kinetics expressed as a function of CO2 solubility

Abstract: Experimental survival curves of Saccharomyces cerevisiae cells exposed to high pressure carbon dioxide (HPCD) treatments under several constant temperatures (35, 40 and 50 °C), pressures (7.5, 10.0 and 13.0 MPa) and suspended in distilled water with different sodium phosphate monobasic buffer concentrations (0.02, 0.10, 0.20 and 0.40 M) were obtained. The Peleg model was applied to the isobaric and isothermal conditions described by the power law equation log[S(t)] = −btn, where S(t) is the momentary survival ratio and ‘b’ and ‘n’ are the rate and the shape parameters, respectively. The values of the coefficients ‘b’ and ‘n’ were calculated for each experiment at fixed pressure and temperature. For each suspending medium the power law model was proposed to describe the combined effects of pressure and temperature. Taking into account the CO2 solubility as a function of the sodium phosphate monobasic concentration, ‘b’ and ‘n’ were correlated to the CO2 solubility values and temperature. An equation was proposed for ‘b’ as a function of CO2 solubility and temperature while ‘n’ was a weak function of temperature. The resulting equation was much simpler that the one obtained correlating the microbial inactivation to pressure and temperature and, more important, it was independent of the suspending medium. The results indicate that the coupling of carbon dioxide solubility, also predicted with commercial software, and the use of inactivation models referred to solubility and temperature may provide a powerful instrument for the interpretation of microbial inactivation experiments and for the design of HPCD processes and equipments.

Cationic surfactant adsorption on silica gel and its application for wastewater treatment

Abstract: The adsorption of cetyltrimethylammonium bromide (CTAB), a well known cationic surfactant on silica gel and its application for organic bearing wastewater treatment was studied in detail. The study was conducted for both CTAB-spiked distilled water and real wastewater. The studies on adsorbent dose variation and removal kinetics were conducted to find the optimum dose and equilibrium contact time for CTAB removal. Interestingly, the adsorption capacity was found to be very high for real wastewater and the reaction occurred very rapidly compared to that of CTAB-spiked distilled water samples. The kinetic study revealed that the reaction followed the pseudo-second order reaction kinetics model. The isotherm followed four region isotherm models. The effects of various parameters such as pH, presence of electrolytes and operating conditions on the adsorption process were studied. High adsorption capacity was observed in presence of electrolytes and in alkaline condition. Kinetic study determined the rate limi...

Studies on the Water Absorption of Bamboo-Epoxy Composites: The Effect of Silane Treatment

Abstract: The effect of silane treatments on the water absorption properties of bamboo matting reinforced epoxy composites were investigated. Treatments using γ-Aminopropyltriethoxy silane, 3-trimethoxysilylpropyl methacrylate, Vinyltris(2-methoxyethoxy)silane, Bis[3-(triethoxysilyl)propyl] tetrasulfide, 3-aminopropyltrimethoxy silane and n-Octyltrimethoxy silane were carried out to study the water absorption property of the bamboo composites. Water absorption in the composites was studied by long-term immersion and 2 h boiling in distilled water. The process of absorption of water was found to follow the kinetics and mechanism described by Fick's theory. Only aminosilanes have shown the positive effects, but to a limited degree. It has been found that among the various silanes used only aminopropyltriethoxy silane treatment is suitable for bamboo-epoxy composite. Aminopropyltriethoxy silane-treated bamboo fiber composite has decreased the water uptake from 41.42% to 36.87%.

Water-induced hypo-osmotic test for the evaluation of canine sperm membrane integrity.

Abstract: The purpose of this study was to investigate the efficiency of the water test to evaluate the functional membrane integrity of ejaculated canine sperm after collecting, cooling, and freezing-thawing. Twenty-five ejaculates were obtained from 12 stud dogs by digital manipulation. Sperm-rich fractions were evaluated, diluted, cooled at 5oC and frozen-thawed. A conventional hypo-osmotic swelling test (HOST) using a fructose solution (60 mOsm/l) was compared with a HOST using distilled water (0 mOsm/l), for evaluation of the functional integrity of the plasma membrane in fresh, cooled, and frozen-thawed semen. Distilled water detected a higher percentage of reacted sperm in fresh semen (91.2 ± 0.1%) than the conventional HOST (90.6 ± 0.1%; P 0.05). Regardless of the test used, there was a decrease in the mean percentage of reacted sperm after equilibrium and freezing-thawing (P < 0.05). In conclusion, this study demonstrated that water can efficiently replace conventional fructose-based hypo-osmotic media for evaluation of the functional integrity of the plasma membrane of ejaculated fresh, cooled, and frozen– thawed canine sperm.

Análise da hidratação do arroz na parboilização

Abstract: The aim of this work was to study the water uptake phenomenon during soaking of husk rice (IRGA 424) under different temperatures. Grains of husk rice with initial water content of 0.1364 (d.b.) imbibed in distilled water at temperatures of 35, 45, 55, and 75 oC were used. A temperature increase resulted in an increase in the water absorption rate. The Peleg's model fitted satisfactory to the experimental data of water absorption kinetics. The effective diffusion coefficient increased with an increase in temperature ranging from 0.80 to 9.18 x 10-11 m2/s. The dependency of the effective diffusion coefficient on temperature can be described by the Arrhenius relationship for the temperature range studied, activation energy of 33.2 kJ.mol-1.

Influence of pH and Temperature on Kinetics of Ceftiofur Degradation in Aqueous Solutions

Abstract: The objective of this study was to evaluate the stability of ceftiofur (1 mg mL(-1)) in aqueous solutions at various pH (1, 3, 5, 7.4 and 10) and temperature (0, 8, 25, 37 and 60 degrees C) conditions. The ionic strength of all these solutions was maintained at 0.5 M. Ceftiofur solutions at pH 5 and 7.4 and in distilled water (pH = 6.8) were tested at all the above temperatures. All other solutions were tested at 60 degrees C. Over a period of 84 h, the stability was evaluated by quantifying ceftiofur and its degradation product, desfuroylceftiofur, in the incubation solutions. HPLC was used to analyse these compounds. At 60 degrees C, the rate of degradation was significantly higher at pH 7.4 compared with pH 1, 3, 5 and distilled water. At both 60 degrees C and 25 degrees C, degradation in pH 10 buffer was rapid, with no detectable ceftiofur levels present at the end of 10 min incubation. Degradation rate constants of ceftiofur were 0.79+/-0.21, 0.61+/-0.03, 0.44+/-0.05, 1.27+/-0.04 and 0.39+/-0.01 day(-1) at pH 1, 3, 5, 74 and in distilled water, respectively. Formation of desfuroylceftiofur was the highest (65%) at pH 10. The rate of degradation increased in all aqueous solutions with an increase in the incubation temperature. At pH 7.4 the degradation rate constants were 0.06+/-0.01, 0.06+/-0.01, 0.65+/-0.17, and 1.27+/-0.05 day(-1) at 0, 8, 25, 37 and 67 degrees C, respectively. The energy of activation for ceftiofur degradation was 25, 42 and 28 kcal mol(-1) at pH 5, 7.4 and in distilled water, respectively. Desfurylceftiofur formation was the greatest at alkaline pH compared with acidic pH. Ceftiofur degradation accelerated the most at pH 7.4 and was most rapid at pH 10. The results of this study are consistent with rapid clearance of ceftiofur at physiological pH.

Enhancement of Limestone Defluoridation of Water by Acetic and Citric Acids in Fixed Bed Reactor

Abstract: Limestone defluoridation by fixed bed reactor has been studied with water pre-acidified with edible organic acids, viz. acetic acid (AA) and citric acid (CA). The study has been carried out by varying acid concentration, contact time (t), number of repeated use of the same limestone bed (n), and chip size of the crushed limestone using fixed fluoride concentration of 10 mg/L in distilled water and groundwater amended to that concentration of fluoride. The presence of both the acids considerably improved the fluoride removal and the removal increased with increase in the acid concentration. Fluoride removal to less than 0.5 and 1.0 mg/L from initial 5 and 10 mg/L, respectively, have been achieved by the method on treatment with single reactor. The mechanism of fluoride removal in the process thought to be the increase in Ca 2+ activity by dissolution of limestone, which precipitates as CaF 2 . XPS analysis reveals that adsorption also contribute to the fluoride removal along with precipitation. The final pH of water remained within acceptable range for drinking water. Initial concentration of fluoride, effects the removal ability of the limestone particles only to some extent. The influence of other anions on fluoride removal process has a little influence which follows the order phosphate > sulfate > bromide > chloride > nitrate.