Concentrations Of Inorganic Salts Research Articles

Kinetics and Equilibrium of Barium and Strontium Sulfate Formation in Marcellus Shale Flowback Water

AbstractFlowback water from natural gas extraction in Marcellus Shale contains very high concentrations of inorganic salts and organic chemicals. Potential reuse of this water in subsequent hydraulic-fracturing operations may be limited by high concentrations of divalent cations (e.g., Ba, Sr, and Ca). Kinetics of barite and celestite precipitation in flowback waters from different well sites was evaluated in this study. Ba reacted rapidly with sulfate and reached equilibrium within 30 min, whereas Sr reacted slowly and took days to reach equilibrium. Equilibrium concentrations of Ba and Sr predicted by thermodynamics models were compared with experimental results. Activity corrections based on the Pitzer equation provided the best agreement with experimental data for both Ba and Sr. Comparison of barite and celestite precipitation kinetics in actual and synthetic flowback water revealed that there was no observable impact of organics and other minor components in actual flowback water on barite precipita...

Preparation of PVP/TEOS/Nitrates Composite Nanofibers

PVP/[Sr (NO3)2+Mg (NO3)2+TEOS+Eu (NO3)2+Dy (NO3)2] composite nanofibers were prepared via electrospinning, the effect of different electrospinning parameters on the composite nanofibers morphology were investigated. The results revealed that diameter of the composite nanofibers increased at first and then decreased with the increasing of voltage, and the properties of the spinning solution (viscosity and surface tension) increased gradually, but the conductivity decreased at first and then increased with the increasing of PVP content. SEM analysis indicated that its easy to get a good morphological and uniform composite nanofibers when the voltage was 13 ~ 15 kv, inorganic salt content was 5% ~ 6%, and concentration of PVP was 15%.

Influence of Inorganic Salts on the Adsorption of Cationically Modified Starch to Fibers

The article is focused on the influence of inorganic salts on the adsorption of cationically modified starch to fibers. Results show that low concentrations of inorganic salts usually affect the process of adsorption in a positive way. Adsorption efficiency at higher concentrations, however, depends on the type of inorganic salts as well as the sequence of adding inorganic salts and starch to paper suspension.

Effects of Coastal Coal Gangue Highway on Groundwater

At present, the cumulative coal gangue piles up about 4.5 billion tons and annual discharge capacity reaches 300 million tons in China. Emissions of coal gangue wastes national resources and will take up a lot of land. Besides, the ecological environment will be polluted and damaged. Using coal gangue as roadbed filling material can not only solve the difficulty of land expropriation, but also consume a large amount of accumulated coal gangue, which has huge economic and environmental benefits. Through laboratory soak test and leaching test, this paper analyses the inorganic salt content and heavy metals of coal gangue used in Xing Fen expressway. Groundwater in Xing Fen highway was captured, detected, evaluated and its quality was good or excellent. In this project, the effects of coal gangue on groundwater meet the regulatory requirements and coal gangue as a new filler can be applied to coastal highway roadbed.

Research of Producing Single Cell Protein with Molasses Wastewater

This paper is to study the optimum conditions for extracting the protein feed by using the mixed microbial fermentation. And using the single factor and orthogonal methods, the microbial content as the main indicators, investigated the effects of the combination of strain, strain ratio, the amount of bacteria, fermentation temperature, the concentration of fermentation, fermentation pH, nitrogen sources and inorganic salts and other factors on the fermentation of protein yield. The test results showed that the best fermentation process is sterilization process, the best combination of strains of Geotrichum candidum, Candida tropicalis and Candida utilis yeast, the cast of bacteria was 10%, the best molasses fermentation concentration 20g / 100 mL, and temperature 30 ° C, initial pH 5.0, appropriate amount of Yeast extract, magnesium sulfate, potassium dihydrogen phosphate and super phosphate. The Test provides a theoretical and experimental basis for Molasses wastewater utilization

Cloud point, fluorimetric and 1H NMR studies of ibuprofen-polymer systems

Influence of six polymers viz. hydroxyethyl cellulose (HEC), hydroxypropyl methyl cellulose (HPMC), polyethylene glycol (PEG), polyvinyl pyrrolidone (PVP), sodium carboxy methyl cellulose (NaCMC) and dextran sulfate (DxS) on solution properties of amphiphilic drug ibuprofen (IBF) has been described in this work. As only HPMC showed the clouding behavior (among the polymers employed herein), its cloud point (CP) was studied in detail in presence of varying amounts of IBF containing different fixed concentrations of inorganic salts (NaCl, NaNO3, Na2SO4, KBr and KNO3). Presence of all these salts had CP reducing effect. By means of steady state fluorescence quenching studies, average aggregation number of IBF aggregates (Nagg) in the presence of varying amounts of the mentioned polymers were evaluated and discussed. 1H NMR studies show that the magnitude of chemical shifts (δ) varies with the nature of the polymer.

The effect of pH on the toxicity of fatty acids and fatty acid amides to rainbow trout gill cells

Harmful algal blooms (HABs) expose aquatic organisms to multiple physical and chemical stressors during an acute time period. Algal toxins themselves may be altered by water chemistry parameters affecting their bioavailability and resultant toxicity. The purpose of this study was to determine the effects of two abiotic parameters (pH, inorganic metal salts) on the toxicity of fatty acid amides and fatty acids, two classes of lipids produced by harmful algae, including the golden alga, Prymnesium parvum, that are toxic to aquatic organisms. Rainbow trout gill cells were used as a model of the fish gill and exposed to single compounds and mixtures of compounds along with variations in pH level and concentration of inorganic metal salts. We employed artificial neural networks (ANNs) and standard ANOVA statistical analysis to examine and predict the effects of these abiotic parameters on the toxicity of fatty acid amides and fatty acids. Our results demonstrate that increasing pH levels increases the toxicity of fatty acid amides and inhibits the toxicity of fatty acids. This phenomenon is reversed at lower pH levels. Exposing gill cells to complex mixtures of chemical factors resulted in dramatic increases in toxicity compared to tests of single compounds for both the fatty acid amides and fatty acids. These findings highlight the potential of physicochemical factors to affect the toxicity of chemicals released during algal blooms and demonstrate drastic differences in the effect of pH on fatty acid amides and fatty acids.

Aggregation and phase separation behavior of an amphiphilic drug promazine hydrochloride under the influence of inorganic salts and ureas

Self-association and phase separation phenomena of an amphiphilic phenothiazine drug promazine hydrochloride (PMZ) in the absence and presence of inorganic salts (NaF, NaCl and NaBr) and ureas (urea and thiourea) have been investigated in the present study. By the increase in temperature the critical micelle concentration (cmc) of drug PMZ first increases then decreases. Maximum cmc values were obtained at 303.15K in presence or absence of additives (salts/ureas). Decrease in cmc occurs by the addition of the inorganic salts which is explained on the basis of nature and ion size. Ureas (urea and thiourea) decreased the cmc at low concentration; however, at higher concentrations, increase in cmc was observed with both the additives. Increasing inorganic salt concentrations caused an increase in the cloud point (CP) of PMZ, whereas urea decreased the CP. Significant thermodynamic parameters were also evaluated and discussed.

Solar light-induced photocatalytic degradation of methyl red in an aqueous suspension of commercial ZnO: a green approach

The potential of commercial ZnO as a heterogeneous photocatalyst for the degradation of methyl red (MR; C. I. Acid Red 2) under solar light irradiation was considered. The effect of initial concentration of MR, catalyst loading, pH, light intensity, radical scavengers, and inorganic salts was studied. The rate of decolorization followed first-order kinetics with respect to dye concentration. Under ambient and neutral pH condition, the catalyst at a dose of 0.5 g/L could decolorize MR (initial conc. 30 mg/L) up to 99% in 1 h. The COD removal under similar situation was ∼53%. The mineralization of MR was found to be dependent on catalyst dose and time of solar light irradiation. Thus, mineralization up to 80% was possible for the same solution using catalyst at 1 g/L dose. The method was free from interference due to Cl−, SO42-, NO3-, Ca2+, Fe2+/3+, humic acid, oxalic acid, and citric acid. However, it was strongly interfered by H2PO4-, maleic acid, malic acid, and tartaric acid. Studies showed that the reaction was mostly governed by singlet oxygen and superoxide radical. High turnover frequency and recycle ability of the catalyst made the process economical. The recovered ZnO could degrade MR up to 86 and 79% after the first and second cycle under identical experimental conditions. A cost-benefit analysis was made to evaluate the efficacy of the catalyst in relation to the commercial TiO2 and silver-doped TiO2. Further, the efficiency of the present method for MR degradation was compared with those of the other methods involving UV and visible light, and in the presence of nano-ZnO and commercial ZnO.

Design of Phosphonium-Type Zwitterion as an Additive to Improve Saturated Water Content of Phase-Separated Ionic Liquid from Aqueous Phase toward Reversible Extraction of Proteins

We designed phosphonium-type zwitterion (ZI) to control the saturated water content of separated ionic liquid (IL) phase in the hydrophobic IL/water biphasic systems. The saturated water content of separated IL phase, 1-butyl-3-methyimidazolium bis(trifluoromethanesulfonyl)imide, was considerably improved from 0.4 wt% to 62.8 wt% by adding N,N,N-tripentyl-4-sulfonyl-1-butanephosphonium-type ZI (P555C4S). In addition, the maximum water content decreased from 62.8 wt% to 34.1 wt% by increasing KH2PO4/K2HPO4 salt content in upper aqueous phosphate buffer phase. Horse heart cytochrome c (cyt.c) was dissolved selectively in IL phase by improving the water content of IL phase, and spectroscopic analysis revealed that the dissolved cyt.c retained its higher ordered structure. Furthermore, cyt. c dissolved in IL phase was re-extracted again from IL phase to aqueous phase by increasing the concentration of inorganic salts of the buffer solution.

Formation of aqueous-phase α-hydroxyhydroperoxides (α-HHP): potential atmospheric impacts

Abstract. The focus of this work is on quantifying the degree of the aqueous-phase formation of α-hydroxyhydroperoxides (α-HHPs) via reversible nucleophilic addition of H2O2 to aldehydes. Formation of this class of highly oxygenated organic hydroperoxides represents a poorly characterized aqueous-phase processing pathway that may lead to enhanced SOA formation and aerosol toxicity. Specifically, the equilibrium constants of α-HHP formation have been determined using proton nuclear-magnetic-resonance (1H NMR) spectroscopy and proton-transfer-reaction mass spectrometry (PTR-MS). Significant α-HHP formation was observed from formaldehyde, acetaldehyde, propionaldehyde, glycolaldehyde, glyoxylic acid, and methylglyoxal, but not from methacrolein and ketones. Low temperatures enhanced the formation of α-HHPs but slowed their formation rates. High inorganic salt concentrations shifted the equilibria toward the hydrated form of the aldehydes and slightly suppressed α-HHP formation. Using the experimental equilibrium constants, we predict the equilibrium concentration of α-HHPs to be in the μM level in cloud water, but it may also be present in the mM level in aerosol liquid water (ALW), where the concentrations of H2O2 and aldehydes can be high. Formation of α-HHPs in ALW may significantly affect the effective Henry's law constants of H2O2 and aldehydes but may not affect their gas-phase levels. The photochemistry and reactivity of this class of atmospheric species have not been studied.

The effect of inorganic salt type and concentration on hydrophilic drug loading into microspheres using the emulsion/solvent diffusion method

Aim: In order to avoid gastric irritation caused by tolmetin sodium (TS), gastro resistant Eudragit® S 100 microsphere formulations were prepared with the emulsion/solvent diffusion method.Materials: Considering the high water solubility of the TS molecule, the effects of the presence of inorganic salt (NaCl, NaBr and KH2PO4; 0.1 M and 1.0 M) in external phase and external phase pH on the encapsulation efficiency were evaluated.Results: Percentage yield value was found to vary between 55.8% and 72.1%. Improvement in encapsulation efficiency was determined by increasing concentrations of NaCl, NaBr and KH2PO4. The microspheres were observed to have a spherical shape and the measured particle size values varied between 52.1 and 81.5 µm. The released amounts of the drug were found to be low as the inorganic salt concentrations increased.Conclusion: Conclusively, drug release in stomach pH was significantly prevented by the microspheres prepared using Eudragit® S 100 polymer, and these formulations are considered to be a model for other orally administered drugs with similar problems.

Effect of buffer systems and disaccharides concentration on Podoviridae coliphage stability during freeze drying and storage

The aims of this study were to determine the stability of Podoviridae coliphage CA933P during lyophilization and storage in different media, and to establish similarities between the results obtained and those expected through mechanisms described for proteins stabilization during freeze-drying.PBS and SM buffer were assayed as lyophilization media. The effect of inorganic salts concentration as well as the addition of disaccharides on phage stability during freeze-drying and storage was also studied.The addition of low sucrose concentration (0.1moll−1) to SM buffer stabilized phage during freezing and drying steps of the lyophilization process, but higher sugar concentrations were detrimental to phage stability during freeze-drying. Sucrose stabilized phage during storage for at least 120days. The lyoprotective effect of low concentrations of disaccharides during the drying step of the lyophilization of proteins as well as the stabilization of the freeze-dried product in time correlated with the results obtained for phage CA933P.

Performance analysis of forward osmosis processes from the integral equation theory

We solved the Ornstein–Zernike integral equation to investigate non-linear behavior of osmotic pressure of solutions containing high concentrations of inorganic salts. Net interactions between molecules are assumed to be Lennard–Jones (LJ) potential, and various force fields were used to determine the potential parameters. Relationship between the LJ parameters and permeate flux are discussed, and relative significance of the osmotic pressure and diffusion coefficient on water flux in forward osmosis was investigated.

Determination of N-methylcarbamate pesticides in vegetables by poly(methacrylic acid-co-ethylene glycol dimethacrylate) monolith microextraction coupled with high performance liquid chromatography

A simple, rapid and sensitive method for simultaneous determination of three N-methylcarbamate pesticides (carbaryl, pirimicarb, and isoprocarb) in vegetables was developed by coupling polymer monolith microextraction (PMME) to high-performance liquid chromatography (HPLC). A poly(methacrylic acid-co-ethylene glycol dimethacrylate) monolith was selected as the extraction medium for PMME. To achieve optimum extraction performance, several parameters were investigated, including desorption solvent, desorption flow rate, sample flow rate, sample volume, sample pH values, inorganic salt and organic solvent content of the sample solution. Under the optimum experimental conditions, the method provides an acceptable linearity (5-5000μg/kg), low limits of detection (0.36-2.6μg/kg), good precision (intra-day relative standard deviations<2.53%, inter-day relative standard deviations <6.36%). Finally, the developed method was successfully applied to the determination of N-methylcarbamate pesticides in vegetables, and the trueness was evaluated by recovery experiments. The obtained relative recoveries were in the range of 70.4-98.5%. This PMME method integrates sample extraction, purification, and preconcentration of analytes into one single step and it also has several advantages such as solvent-free extraction, small sample volume, high enrichment, convenience, and flexibility operation.

Impact of relative humidity and particles number size distribution on aerosol light extinction in the urban area of Guangzhou

Abstract. In the urban area of Guangzhou, observations on aerosol light extinction effect were conducted at a monitoring site of the South China Institute of Environmental Sciences (SCIES) during April 2009, July 2009, October 2009 and January 2010. The main goal of these observations is to recognise the impact of relative humidity (RH) and particles number distribution on aerosol light extinction. PM2.5 was sampled by Model PQ200 air sampler; ions and OC/EC in PM2.5 were identified by the Dionex ion chromatography and the DRI model 2001 carbon analyser, respectively; particles number size distribution was measured by TSI 3321 APS, while total light scattering coefficient was measured by TSI 3563 Nephelometer. Chemical composition of PM2.5 was reconstructed by the model ISORROPIA II. As a result, possible major components in PM2.5 were (NH4)2SO4, Na2SO4, K2SO4, NH4NO3, HNO3, water, POM and EC. Regarding ambient RH, mass concentration of PM2.5 ranged from 26.1 to 279.1 μg m−3 and had an average of 94.8, 44.6, 95.4 and 130.8 μg m−3 in April, July, October and January, respectively. With regard to the total mass of PM2.5, inorganic species, water, POM, EC and the Residual accounted for 34–47%, 19–31%, 14–20%, 6–8% and 8–17%, respectively. Under the assumption of "internal mixture", optical properties of PM0.5–20 were estimated following the Mie Model. Optical refractive index, hygroscopic growth factor and the dry aerosol density required by the Mie Model were determined with an understanding of chemical composition of PM2.5. With these three parameters and the validated particles number size distribution of PM0.5–20, the temporal variation trend of optical property of PM0.5–20 was estimated with good accuracy. The highest average of bep,pm0.5–20 was 300 Mm−1 in April while the lowest one was 78.6 Mm−1 in July. Regarding size distribution of bep,pm0.5–20, peak value was almost located in the diameter range between 0.5 and 1.0 μm. Furthermore, hygroscopic growth of optical properties of PM0.5–20 largely depended on RH. As RH increased, bep,pm0.5–20 grew and favoured a more rapid growth when aerosol had a high content of inorganic water-soluble salts. Averagely, fbep,pm0.5–20 enlarged 1.76 times when RH increased from 20% to 90%. With regard to the temporal variation of ambient RH, fbep,pm0.5–20 was 1.29, 1.23, 1.14 and 1.26 on average in April, July, October and January, respectively.

Engineering preliminaries to obtain reproducible mixtures of atelocollagen and polysaccharides

The critical stage in producing blends of biomacromolecules consists in the mixing of component solutions to generate homogenous diluted colloidal systems. Simple experimental investigations allow the establishment of the design rules of recipes and the procedures for preparing homogenous and compositionally reproducible mixtures. Starting from purified solutions of atelocollagen, hyaluronan and native gellan, having as low as possible inorganic salts content, initial binary and ternary mixtures can be prepared up to a total dry matter content of 0.150g/dL, in no co-precipitating conditions. Two pH manipulation ways are feasible for homogenous mixing: (i) unbuffered prior correction at pH5.5, and (ii) “rigid” buffering at pH9.0, using organic species. Atelocollagen including co-precipitates can be obtained in the presence of one or both polysaccharides, preferably in pH domains far from the isoelectric point of scleroprotein. A critical behavior has been observed in mixtures containing gellan, due to its macromolecular dissimilarities compared with atelocollagen. In optimal binary mixtures, the coordinates of threshold points on the phase diagrams are 0.028% w/w atelocollagen/0.025% w/w hyaluronan, and 0.022% w/w atelocollagen/0.020% w/w gellan. Uni- or bi-phasic ternary systems having equilibrated ratios of co-precipitated components can be prepared starting from initial mixtures containing up to 0.032g/dL atelocollagen, associated with, for example, 0.040g/dL hyaluronan and 0.008g/dL gellan, following the first pH manipulation way.

Simultaneous removal of chemical oxygen demand, turbidity and hardness from biologically treated citric acid wastewater by electrochemical oxidation for reuse

In this study, we investigated the use of an electrochemical oxidation process to simultaneously remove chemical oxygen demand (COD), turbidity, and hardness from biologically treated citric acid wastewater that was non-biodegradable and contained high concentrations of inorganic salts. We employed a Ti/RuO2–IrO2 anode system to analyse the effects of electric voltage and initial chloride concentration on COD, turbidity, and hardness removal as well as on energy consumption. Under optimal conditions (electric voltage of 9V, initial chloride concentration of 3000mgL−1), organic pollutants were almost completely mineralised after 60min of electrolysis. The resulting COD (6mgL−1) and turbidity (3NTU) of effluent was within the Water Reuse Standard of China (COD<30mgL−1, turbidity<5NTU) while energy consumption (Es) and general current efficiency (GCE) were 99kWhkgCOD−1 and 30%, respectively. We also found that electric voltage and initial chloride concentrations increased the rate of hardness removal. Further investigation revealed that organics were mainly degraded by electrochemical oxidation of humic and fulvic acid-like substances, and hardness was primarily removed via the production of CaMg(CO3)2 precipitate on the cathode surface.

Assessment of the Effects of Wood Processing Industries in Selected Parts of Delta State, Nigeria, On the Soils and Vegetation in Their Vicinities

Soil and vegetation samples collected from the vicinities of wood processing industries from selected parts of Delta State, Nigeria were analyzed for their metal levels and physicochemical properties inorder to assess the impact of the industries on the surrounding environment. The pH values ranged from 4.9 to 6.0 indicating that the soils were acidic. The electrical conductivity values ranged from 54.80 to 75.90uScm which is suggestive of significant concentration of soluble inorganic salts. The total organic carbon and total nitrogen ranging from 0.25 to 0.45% and from 0.11 to 0.69% respectively showed some presence of degradable and compostable materials as well as organic matters in the soils. The cation exchange capacity which ranged from 1.23 to 3.95cmolkg -1 indicated the low capacity of the soils to adsorb metals. The mean levels of the heavy metals in the soils ranged from 12.69 to 272 mgkg -1 with abundance trend of Fe > Mn > Cu > Zn > As > Cr > Pb > Cd while those of the vegetation ranged from 4.17 to 47.10mgkg -1 with abundance trend of Fe > Mn > Zn > Cu > Cr > Pb > As. The metal levels in both the soil and vegetation samples in all the sites were significantly higher than the levels obtained in the control site which is suggestive of significant contribution of the industries to these elevated levels. The contamination/pollution index values of the metals in the soil samples showed generally contamination levels for all the metals except copper which showed moderate pollution. The soil plant transfer values indicate medium, accumulation for all the metals. Although the overall results showed evidence of contamination of the soils by heavy metals, the present levels do not pose any environmental risk or health hazard.

Research to Deal with the Pulping Black Liquor by Using &lt;i&gt;Aspergillus niger&lt;/i&gt;

We treat black liquor using Aspergillus niger to extract lignin and to improve the utilization value of pulping black liquor. Results show that: The original black liquor directly to the biological treatment by Aspergillus niger, biological bacteria cannot grow, when reaction liquid pH ≤ 9; Inorganic salt concentration ≤7% (mass ratio); The black liquor load ratio is 20% (mass ratio), the condition of Aspergillus niger growth is good, the ability to produce acid is strong. After treatment of Aspergillus niger, liquid pH decreased to 3, Aspergillus niger changes settling performance of lignin, and it’s good for extraction and purification of lignin. Lignin methoxyl content reduced 2.81%, alcoholic hydroxyl content reduced 0.31%, and carboxyl content increased 0.15%.