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Conclusions: Superselective intra-arterial cisplatin infusion with concomitant radiotherapy (RADPLAT) is considered to be one of the treatments of choice for patients with adenoid cystic carcinoma (ACC) who prefer not to undergo radical surgery. Objective: To evaluate the efficacy of RADPLAT for patients with ACC of the head and neck. Patients and methods: Between 2001-2010, nine patients with untreated ACC were given superselective intra-arterial infusion of cisplatin (100-120 mg/m2/week) with simultaneous intravenous infusion of thiosulfate to neutralize cisplatin toxicity and radiotherapy (65-70 Gy). Results: Five patients had tumors arising in the base of the tongue, two in the maxillary sinus, and the remaining two in the nasopharynx. The median follow-up period was 9 years 7 months (9;7) (range = 4;6-12;5), and the 5-year local control (LC), overall survival (OS), and disease-free survival rates were 88.9%, 88.9%, and 55.6%, respectively. The 10-year OS rate was 57.1%, but all patients who remained alive for over 10 years are still alive with disease. Primary tumor recurrence was observed in five of the nine patients, with the median time to recurrence being 6 years (range = 4-9 years). Five of the nine patients had distant metastasis, and of these three patients also had primary recurrence. [ABSTRACT FROM AUTHOR]

A new chiral holmium–sulfate coordination polymer, {Ho4(OH)4(SO4)4(H2O)3}n(1), has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. The X-ray diffraction analysis reveals that1crystallizes in orthorhombic space group P212121and exhibits a unique three-dimensional chiral structure, in which {Ho4} building blocks are linked by SO42–anions to form a high connected binodal network. Furthermore, thermal and luminescence properties of1are investigated in the solid state. [ABSTRACT FROM AUTHOR]

This article gives a broad overview about the status and progress of the sulfate radical-based decontamination technologies. Peroxymonosulfate or persulfate can be activated by energy or a catalyzer to form sulfate radical for rapid and effective degradation of contaminants in homogenous systems. Sulfate radical-based heterogeneous catalysis oxidation has been a major research focus since 2005 because solid catalysts are stable, cost-effective, and easy to recover. The application of sulfate radical in other decontamination technologies and the mechanisms involved are also described and discussed. The main points are summarized and the directions of future researches are suggested in the last section. [ABSTRACT FROM PUBLISHER]

Alkylaminium sulfates are frequently detected in ambient aerosols, and are believed to be important in the nucleation of new particles in the atmosphere, despite the comparatively low gas phase concentrations of amines. In this study, water activities and osmotic coefficients have been measured, using a chilled mirror dew point technique, of aqueous mixtures of sulfuric acid and the following alkylaminium sulfates: methylaminium, ethylaminium, dimethylaminium, diethylaminium, and trimethylaminium sulf-ate. The samples were prepared by mixing solutions of the five corresponding amines and aqueous sulfuric acid and determining the exact aminium to sulfate molar ratios by ion chromatography. The results were correlated using an extended Zdanovskii–Stokes–Robinson equation to enable concentration/water activity rela-tionships to be calculated over the entire composition range from pure aqueous sulfuric acid to pure aqueous aminium sulfate. Water activities and osmotic coefficients for aminium:sulfate ratios of 1:1 (the bisulfate salts) and lower showed great similarity with ammonium bisulfate, but osmotic coefficients for the 2:1 ratio (the aminium sulfates) were significantly larger (and water activities lower) than for ammonium sulfate. These results differ from those obtained in Clegg et al.'s (2013) study. The relative values of the osmotic coefficients, in concentrated solutions, suggest that the numbers of methyl or ethyl groups in the aminium ion may have a stronger lowering effect on water activity than the alkyl chain length. Copyright 2015 American Association for Aerosol Research [ABSTRACT FROM PUBLISHER]

The biocidal efficacy of THPS on oil pipeline biofilms was determined by direct MPN counts of SRB and APB after incubations at various concentrations of THPS for 14 days and also by its inhibitory effects on functional group activities of some oil field microorganisms. THPS was unable to drastically inhibit SRB growth at lower concentrations (0.1–0.3%) but its selective action on the activities of the hNRB and so-NRB further inhibits SRB growth and prevents sulfide formation at lower concentrations (0.2–0.3%). It was also observed that sulfide formation occurred at relatively high concentration of SRB (>106cells/mL) at 0.1% THPS concentration. [ABSTRACT FROM AUTHOR]

In order to study sulphate attack effects on the mechanical behaviour of cementitious materials, the compressive behaviour of such materials subjected to wet-dry cycles of sulphate solution was investigated. Then, their variation of mass was recorded. According to the experimental results, it was observed that the mortars subjected to wet-dry cycles of sulphate attack were more severely damaged than ones immersed in a sulphate solution. In addition, these experimental results showed that the ultimate strength, elastic moduli and mass of samples initially increased with the number of wet-dry cycles and then declined after a certain number of wet-dry cycles. However, the peak strain corresponding to the compressive strength presented a decrease in the initial stage and then increased with the number of wet-dry cycles. Finally, the relationships between the mechanical behaviours and mass increment of such materials were analysed and qualitatively established. [ABSTRACT FROM AUTHOR]

Cyclo[8]pyrrole, an octapyrrolic expanded porphyrin with no meso-linking atoms, was found to interact with a series of anions in the solid state and in a chloroform solution. The anion selectivities have been determined relative to a structurally characterised salt, H2cyclo[8]pyrrole2+·I− ·I3 − , via counter anion exchange. Although cyclo[8]pyrrole demonstrates a general selectivity for sulfate, it interacts well with both the pertechnetate and perrhenate anions. Moreover, it has been shown to act as a phase-transfer catalyst facilitating the extraction of pertechnetate from an aqueous to an organic phase in the presence of sulfate. [ABSTRACT FROM PUBLISHER]

The potential of various graphite materials including Chinese flake graphite, Madagascan flake graphite, natural vein graphite, recycled vein graphite, and synthetic graphite for the preparation of -bisulfate was investigated through electrochemical intercalation method. All the graphite materials were characterized using laser particle size analyzer, SEM analysis, XRD analysis, and X-ray EDS elemental analysis. Chinese flake and Madagascan flake graphite materials were found to be capable of synthesizing GIC-bisulfate through electrochemical intercalation. Natural vein, recycled vein, and synthetic graphite materials did not show any evidence of forming GIC-bisulfate. The formation of GIC-bisulfate was verified through XRD results. Thermal exfoliation volume was observed as an indicator of GIC-bisulfate when the electrochemically treated material was exposed to a sudden thermal shock at a temperature of 850 °C. [ABSTRACT FROM AUTHOR]

Developments in the field of polymer science have led us to the development of Chitosan and PNIPAm mixed pH and temperature responsive hydrogel films. Characterizations were done by Swelling analysis, FTIR, DSC, FESEM and Antibacterial assay. Optimized hydrogel film on swelling analysis does not lose its shape and was not dissolve in to the different buffer solution and at different temperature. FTIR, DSC and FESEM study confirmed the changes in to the hydrogel film after drug absorption. On increasing the temperature and change in pH of the solution, drug absorption increased which was confirmed by zone of inhibition against E. coli. [ABSTRACT FROM AUTHOR]

Sulfate-reducing bacteria (SRB) and hydrogen sulfide were widely present in oil production systems, which are detrimental to oil exploitation industry. An anaerobic denitrifying and sulfide removal bacterial strain, identified asPseudomonas stutzeriDQ1, was isolated from Daqing Oilfield. Starin DQ1 grew well at temperatures 20–40°C, pH 6.5–8.0, and salinity 0–50 g/L of NaCl. Strain DQ1 can completely remove sulfide less than 50.0 mg/L, and decrease the SRB numbers nearly four orders of magnitude. Bioaugmentation of strain DQ1 in oil production system will be a promising approach for simultaneous inhibition of SRB and removal of sulfide in Daqing Oilfield. [ABSTRACT FROM AUTHOR]

The homocysteine theory of arteriosclerosis was discovered by study of arteriosclerotic plaques occurring in homocystinuria, a disease caused by deficiencies of cystathionine synthase, methionine synthase or methylenetetrahydrofolate reductase. According to the homocysteine theory, metabolic and nutritional abnormalities leading to elevation of plasma homocysteine cause atherosclerosis in the general population without these rare enzymatic abnormalities. Through studies of metabolism of homocysteine thiolactone, the anhydride of homocysteine, in cell cultures from homocystinuric children, the pathway for synthesis of sulfate was found to be dependent upon thioretinamide, the amide formed from retinoic acid and homocysteine thiolactone. Two molecules of thioretinamide form the complex thioretinaco with cobalamin, and oxidative phosphorylation is catalyzed by reduction of oxygen, which is bound to thioretinaco ozonide, by electrons from electron transport particles. Atherogenesis is attributed to formation of aggregates of homocysteinylated lipoproteins with microorganisms, which obstruct the vasa vasorum during formation of arterial vulnerable plaques. [ABSTRACT FROM AUTHOR]

A new complex, namely {[Cd(SO4)(IP)]n(1) (IP = 1-H-imidazo[4,5-f][1,10]-phenanthroline), has been prepared and structurally characterized. The adjacent Cd(II) atoms are connected by tridentate-bridging sulfates into a 1D chain, which can be further linked into 2D layerviathe C‒H…N interactions. Furthermore, the luminescent behavior is also explored. [ABSTRACT FROM AUTHOR]

In this study, Fe(VI) was applied to treat three mine tailings containing different amounts of sulphides and heavy metals. Oxidation of sulphides by Fe(VI) was studied at pH 9.2 with variation of solid to solution ratio, Fe(VI) concentration and injection number of Fe(VI) solution. The major dissolved products from the treatment of mine tailings with Fe(VI) solution were sulphate and arsenic. Oxidation efficiency of sulphides was evaluated by reduction efficiency of Fe(VI) as well as by measurement of dissolved sulphate concentration. Even though inorganic composition of three mine tailings was different, reduction fraction of Fe(VI) was quite similar. This result can suggest that Fe(VI) was involved in several other reactions in addition to oxidation of sulphides. Oxidation of sulphides in mine tailing was greatly dependent on the total amount of sulphides as well as kinds of sulphides complexed with metals. Over the five consecutive injections of Fe(VI) solution, dissolved sulphate concentration was greatly decreased by each injection and no more dissolved sulphate was observed at the fifth injection. While dissolved arsenic was decreased lineally up to the fifth injection. Sulphate generation was slightly increased for all mine tailings as Fe(VI) concentration was increased; however, enhancement of oxidation efficiency of sulphides was not directly proportional to the initial Fe(VI) concentration. [ABSTRACT FROM PUBLISHER]

Large amounts of free fatty acids in oil used for the production of biodiesel cause the problems of soap formation and very low yield of biodiesel. To overcome these problems, free fatty acids must be esterified to their esters in the presence of an acid catalyst prior to alkaline-catalyzed transesterification. Sulfated metal oxides are an interesting group owing to their very high acidity. In this study, sulfated aluminium-tin mixed oxide (SO42−/Al2O3-SnO2) catalysts were synthesized and used for esterification of free fatty acids in crude palm oil for the first time. The SO42−/Al2O3-SnO2catalysts were prepared from different Al precursors, calcination temperatures, and sulfate concentrations. Characterization of the catalysts included X-ray diffraction (XRD) and X-ray fluorescence (XRF) techniques, nitrogen adsorption, Fourier transform infrared spectroscopy (FTIR), and potentiometric titration. The results show that the SO42−/Al2O3-SnO2catalyst has very strong acid sites. Different Al precursors lead to different activities of the SO42−/Al2O3-SnO2catalysts. Al2(SO4)3is the best precursor whereas Al(NO3)3is the worst one to prepare the SO42−/Al2O3-SnO2catalyst. The optimum calcination temperature is 450°C. The activity of the SO42−/Al2O3-SnO2catalyst increases with sulfate concentration. Introducing Al2O3to SO42−/SnO2increases its stability during the reusability process. Therefore, SO42−/Al2O3-SnO2is a better candidate than SO42−/SnO2for catalyzing the esterification of free fatty acids in crude palm oil. [ABSTRACT FROM AUTHOR]

The performance of using chicken manure as carbon source to promote sulphate-reducing bacteria (SRB) activity within acidic coal refuse to prevent the generation of acidic leachate was investigated in batch and column bioreactors. The bioreactors showed satisfactory performance in biological sulphate reduction, evidenced by the increase in effluent pH, high removal efficiencies of sulphate and metals, and the presence of large numbers of SRB. Scanning electron microscope-energy dispersive spectrometry (EDS) analysis of the formed precipitate indicated the formation of metal sulphides. Chicken manure was observed to play an important role in this treatment, which could not only provide carbon source but also reduce the adverse effect of strong acidity and metal toxicity on SRB activity. Metal removal could be mainly attributed to sulphides precipitation and sorption to chicken manure. This study indicated that SRB with chicken manure could be a novel alternative used for the prevention of acidic leachate from coal refuse. [ABSTRACT FROM PUBLISHER]

The extraction of propionic acid has been studied by liquid–liquid extraction with poly ethylene glycol /different salts of sulfate aqueous two-phase system (ATPS). In this study, a multilevel factorial design was applied to evaluate the effects of four independent variables (PEG molecular weight, type of salt, salt concentration, and temperature) on propionic acid extraction yield. The statistical significance of each factor was evaluated by an analysis of variance. The results indicated that the type and concentration of salt were the major contributing factors to propionic acid extraction. The PEG4000/ MnSO4system was suitable for the extraction of propionic acid from dilute water. [ABSTRACT FROM AUTHOR]

Burkeite formation is important in saline evaporites and in pipe scales. Burkeite is an anhydrous sulphate-carbonate with an apparent variable anion ratio. Such a formula with two oxyanions lends itself to vibrational spectroscopy. Two symmetric sulphate stretching modes are observed, indicating at least at the molecular level the nonequivalence of the sulphate ions in the burkeite structure. The strong Raman band at 1065 cm−1is assigned to the carbonate symmetric stretching vibration. The series of Raman bands at 622, 635, 645, and 704 cm−1are assigned to the ν4sulphate bending modes. The observation of multiple bands supports the concept of a reduction in symmetry of the sulphate anion fromTdtoC3vor evenC2v. [ABSTRACT FROM AUTHOR]

Wetland soils of the freshwater coastal deltaic regions of Louisiana have developed under decreasing influence from the Mississippi River, which has resulted in lower available nutrient conditions and sediment input relative to other coastal marshes. A laboratory soil respiration experiment was conducted to measure cumulative carbon dioxide (CO2) and methane (CH4) production in soils from a floating freshwater marsh in response to additions of added ammonium (N), phosphate (P), ammonium (N) + phosphate (P), and sulfate (S). CO2respiration was significantly greater over a 28-day period than controls following ammonium N, phosphorus, and sulfate addition at 10 mg L−1. Nitrogen and phosphorus addition at 10 mg L−1also increased methane production. The lower sulfate amendment (10 mg L−1) did not significantly increase CH4production. In contrast, the greatest sulfate treatment (100 m l−1) significantly reduced total carbon (C) production by inhibiting CH4production. The fact that soil C/N (20.2) and C/P (355) ratios were both relatively low may partially explain why both N and P colimited microbial activity and respiration. While microbial activity of freshwater floating marsh soils was stimulated over the short term with increased ammonium, nitrogen, phosphorus, and sulfate exposure, it is unclear whether the increase would be the same over extended periods or would increase in plant productivity from nutrient additions compensate for any loss in soil carbon. [ABSTRACT FROM PUBLISHER]

Sulfur (S) deficiency effects on nitrogen (N) and S fluxes during vegetative growth of Brassica napus was investigated by tracing15N and34S for 9 d of S-sufficient [1.5 mM sulfate (SO42-)] and S-deficient (0.05 mM SO42-) condition. A significant decrease in leaf osmotic potential and chlorophyll content was apparent after 9 d of S-deficiency. Sulfur uptake during 9 d was remarkably decreased by 94.3% by S-deficiency, whereas no significant change occurred for N uptake. The N and S deriving from uptake were mainly allocated to the leaves in control plants, but the S flow into leaves was largely restricted under S-deficient condition. The remobilization of stored N and S were mainly issued only from leaves in control plants, while from leaves and petiole in S-deficient ones. The remobilization of N and S mainly issued from leaves flows into the roots both in control and S-deficient plants. [ABSTRACT FROM AUTHOR]

In iron toxic wetlands, ferric hydroxide is commonly deposited on rice roots. This study aims to to evaluate the differences in iron plaque formation in rice cultivars from different cropping systems. Thirty days old seedlings of Brazilian rice cultivars from the lowland cropping system (‘BRS Atalanta’ and ‘Epagri 107’) and upland cropping system (‘Canastra’) or both systems (‘BRSMG Curinga’) and the cultivar ‘Nipponbare’ were exposed to iron excess [4 mM iron sulfate heptahydrate (FeSO4.7H2O)] for seven days in nutrient solution. It was observed iron plaque formation and ruptures of the root epidermal cells. The lowland cultivars showed higher Fe content in iron plaque. Iron stain was detected in the root hairs, epidermis, hypodermis, and exodermis. The root exodermis may be contributed to prevent the deposit of iron in the cortex of the lowland cultivars and in the cultivar ‘BRSMG Curinga’. It was observed in plants with iron plaque formation significant reductions in the shoot content of phosphorous, manganese and magnesium due to different causes. The differences in iron plaque formation among the cultivars might be an indicative of variations in exodermis selectivity, root oxidative capacity, and iron nutrition mechanisms. [ABSTRACT FROM PUBLISHER]

The groundwater system in Olkiluoto, Finland, is stratified with a mixing layer at a depth of approximately 300 m between sulphate-rich, methane-poor and sulphate-poor, methane-rich groundwaters. New sequence library data obtained by 454 pyrotag sequencing of the v4v6 16S rDNA region indicated that sulphate-reducing bacteria (SRB) dominated the mixing layer while SRB could not be detected in the deep sulphate-poor groundwater samples. With the indispensable support of the sequence data, it could be demonstrated that sulphate was the only component needed to trigger a very large community transition in deep sulphate-poor, methane-rich groundwater from a non-sulphate-reducing community comprisingHydrogenophaga,Pseudomonas,Thiobacillus,Fusibacter, andLutibacterto a sulphate-reducing community withDesulfobacula,Desulfovibrio,Desufobulbaceae,Desulfobacterium,Desulfosporosinus, andDesulfotignum. Experiments with biofilms and planktonic microorganisms in flow cells underin situconditions confirmed that adding sulphate to the sulphate-poor groundwater generated growth of cultivable SRB and detectable SRB-related sequences. It was also found that the 16S rDNA diversity of the biofilms was conserved over 103 d and that there was great similarity in diversity between the microorganisms in the biofilms and in the flowing groundwater. This work demonstrates that the presence/absence of only one geochemical parameter, i.e., sulphate, in the groundwater significantly influenced the diversity of the investigated subterranean microbial community. [ABSTRACT FROM PUBLISHER]

In this study, anaerobic granular sludge with sulphate-reducing bacteria (SRB) was applied to treat Cu2+-,-containing wastewater in an expanded granular sludge bed reactor. The migration and enrichment of copper in anaerobic granular sludge were envaluated. By analysing the sludge with X-ray diffraction, copper was determined to be present as covellite (CuS) in the sludge. Observations at the microscopic level showed that CuS precipitates were absorbed onto granules and gradually migrated from the outer to the interior layer of the granule over time and finally accumulated in the core of the granular sludge. Because of the migration of the CuS precipitates and the protection of the extracellular polymeric substances matrix, SRB were able to tolerate copper concentrations up to 10 mg/L. A copper removal efficiency of about 96% was observed at a steady state for 3 months, and copper was enriched in the granular sludge. [ABSTRACT FROM PUBLISHER]

The absorbing aerosols, primarily black carbon (BC), play a unique and important role in the Earth’s climate system primarily by warming the atmosphere. This warming effect contrasts with the cooling effect of aerosols such as sulphates that are mostly of the scattering type. With a view to studying the characteristics of both absorbing and scattering aerosols within the boundary layer, collocated measurements using an aethalometer and a nephelometer were carried out over Dibrugarh (27.3° N, 94.6°E, 111 m amsl), Northeast India. The diurnal variation of BC mass concentration (MBC) shows a primary peak during late evening (2000–2200 local time (LT)) while a weak secondary peak is observed in the morning (0600–0800 LT). A seasonal shift in diurnal peakMBCwas also observed. Both diurnal and seasonal variations in the scattering coefficient (βsca) resemble that ofMBC. It may, therefore, be inferred that the majority of both absorbing and scattering types of aerosol prevalent over the study location have common production sources. The seasonal spectral variation in absorption coefficient (βabs) shows monotonic decrease from shorter to longer wavelength in all seasons. The wavelength dependence of absorption by aerosols, as obtained from the absorption Ångström exponent (αabs), indicates a stronger presence of absorbing aerosols originating from biomass burning than those originating from fossil fuel burning over Dibrugarh. The high values of single-scattering albedo (SSA) obtained over Dibrugarh reveal that the scattering type of aerosol is predominant in the ambient air. SSA, together withMBCm, is a useful parameter for estimation of radiative forcing and hence the climatic impact of aerosols. [ABSTRACT FROM AUTHOR]

Separation of nickel(II) and cadmium(II) ions from sulphate solution with use of supported liquid membranes (SLM) has been studied. Di(2-ethylhexyl)phosphoric acid (D2EHPA) dissolved in kerosene was used as the ion carrier. Obtained data were compared with data from polymer inclusion membranes (PIM) experiments. It was shown that use of SLM membranes enables separation of Ni(II) and Cd(II) ions. Experimental results data show that faster transport and higher recovery factor values were obtained for supported liquid membranes. [ABSTRACT FROM PUBLISHER]

The flux of Mn(II) transfer in-Cyanex 272-kerosene system was investigated using the single-drop technique and the flux method of data treatment. The empirical flux equation at 303 K is:Ff = 10−3.6[Mn(II)](1 + 104.5[H+])−1(1 + 1.58 [])−1. The activation energy (Ea) varies within 15–59 kJ/mol depending on experimental conditions. On analyzing the flux equation and with the help ofEavalues, it is concluded that either the extraction reaction step Mn2+ + A− → MnA+or the diffusion of reactants (or products) to (or from) the reaction site is rate controlling depending on the reaction parameters. At high pH and at intermediate pH-higher temperature regions, lowEa(≤20 kJ/mol) suggests that the process is under diffusion control. But at low pH and at intermediate pH-lower temperature regions, highEa(≥50 kJ/mol) suggests that the process is under chemical control. High negative ΔS±value indicates that the slow extraction reaction step occurs by means of an SN2 mechanism. [ABSTRACT FROM PUBLISHER]

The influence of synergistic interaction between sodium dodecylsulfate (SDS) and N,N-dimethyldodecan-1-amine oxide (DDAO) on their adsorption at air/water and solid/water interfaces at 20°C is investigated. The critical micelle concentration values obtained from surface tension measurements indicated strong synergism between SDS and DDAO, according to regular solution model. The excess surface concentration (Γ) and the minimum occupied area by single and mixed surfactant monomers (Amin) at liquid/air interface were also calculated. The adsorption onto the activated charcoal and silica was then measured to find out the correlation between surfactant synergism and their adsorption at solid/water interface. The amounts of surfactant adsorbed onto 1 wt% activated charcoal follow the trend: SDS/DDAO > DDAO > SDS. SDS molecules do not adsorb onto 5 wt% silica substrate, while SDS/DDAO mixed system was found to have the highest adsorption behavior. The obtained indicate that SDS can be removed from water by mixing it with amphoteric surfactant. [ABSTRACT FROM AUTHOR]

The optimal conditions of separation of zirconium(IV) from hafnium(IV) on Purolite S-957 ion-exchange resin in their sulfate aqueous solutions using a static method has been determined to be 0,07 M Zr(SO4)2(containing 2% Hf) in 0,5 M H2SO4.Higher Zr(IV) concentration causes a lowering of the Zr/Hf separation efficiency due to the oligocondensation of mononuclear Zr(IV) and Hf(IV) ions resulting in the formation of Zr(IV) or mixed Zr(IV)-Hf(IV) oligohydroxo-sulfato ions, which is not prevented by the parallel increase of acidity of the solution. The same effect can be observed when analyzing the shapes of adsorption isotherms, which are similar for both Zr(IV) and Hf(IV). [ABSTRACT FROM PUBLISHER]

A total of 42 rain water samples were collected for a period of one year, March 2005 to February 2006, at Jorhat, a rural site of North-East India. The pH of the samples varied from 4.1 to 7.1 with a mean 5.5 showing the acidic nature of rainwater with reference to 5.6 (natural pH of rain water due to CO2 equilibrium in the atmosphere). More than 50% of the rain events have been found to be acidic. Mean concentrations of major ions in the rain water followed the order SO > Ca2+ > NH > NO > PO > H+ > HCO > Na+ > Mg2+ > Cl– > K+ > F–. Ca2+, NH and Mg2+ have shown a neutralization factor less than 1, indicating partial neutralization of anions. EFSoil indicated that soil plays a major role in rain water composition. Maximum concentration for most of the ionic species has been observed during winter followed by summer, post-monsoon and monsoon periods, respectively. Occurrence of acid rain events has been observed throughout the year suggesting that the soil is acidic. [ABSTRACT FROM AUTHOR]

Two new complexes, {[Zn(imb)(SO4)]·H2O}n(1) and {[Cd2(imb)2(SO4)2(H2O)]·CH3OH}n(2) (imb?=?2-(1H-imidazol-1-methyl)-1H-benzimidazole), have been solvothermally synthesized. Single-crystal X-ray diffraction shows that1displays a 2-D (4,4) network, which is further extended to a 3-D supramolecular structure by hydrogen bonding interactions. Complex2exhibits a 3-D framework with (3,5)-connected (42·6)2(42·65·83)2topology. The results indicate that changing metal ions can influence the coordination modes of sulfate, and then affect the structures of the complexes. In addition, IR and UV–vis spectra, powder X-ray diffraction patterns, thermogravimetric analyses, and fluorescent properties of both complexes have been investigated. Two new complexes, {[Zn(imb)(SO4)]·H2O}n(1) and {[Cd2(imb)2(SO4)2(H2O)]·CH3OH}n(2), have been synthesized and characterized by single crystal X-ray diffraction. Additionally, their UV–vis, IR, Thermogravimetric analyses and fluorescent properties are also investigated. [ABSTRACT FROM AUTHOR]

Analytical expressions have been derived for the vertical detachment energy (VDE) for hydrated sulphate (SO2 −4) and oxalate (C2O2 −4) dianions that can be used to calculate the same over a wide range of cluster sizes including the bulk from the knowledge of VDE for a finite number of stable clusters. The calculated bulk detachment energies are found to be very good in agreement (within 5%) with the available experimental results for both the systems. It is observed that two or more water molecules will be essential for the stability of sulphate and oxalate dianions against spontaneous electron loss and this is consistent with the experiment. We have, for the first time, provided a scheme to calculate the radius of the solvent berg for sulphate and oxalate dianions. The calculated conductivity values for the sulphate and oxalate dianions using Stokes–Einstein relation and the radius of solvent berg are found to be very good in agreement (within 4%) with the available experimental results. [ABSTRACT FROM AUTHOR]

Zinc and cadmium sulfate and nitrate complexes with hexamethylenetetramine, [Zn(hmta)2(H2O)4]2+·[Zn(H2O)6]2+··6H2O (1),·n·2nH2O (2), [Zn(H2O)6]2+·2(hmta)··4H2O (3) and [Cd(hmta)(NO3)2(H2O)2]n(4), have been synthesized and characterized by elemental and thermal analysis, IR spectroscopy, and X-ray crystallography. [ABSTRACT FROM AUTHOR]

The authors analyze the sensitivities of source regions in East Asia to PM2.5(particulate matter with an aerodynamic diameter of ≤2.5 µm) concentration at Fukue Island located in the western part of Japan by using a regional chemical transport model with emission sensitivity simulations for the year 2010. The temporal variations in PM2.5concentration are generally reproduced, but the absolute concentration is underestimated by the model. Chemical composition of PM2.5in the model is compared with filter sampling data in spring; simulated sulfate, ammonium, and elemental carbon are consistent with observations, but mass concentration of particulate organic matters is underestimated. The relative contribution from each source region shows the seasonal variation, especially in summer. The contribution from central north China (105°E–124°E, 34°N–42°N) accounts for 50–60% of PM2.5at Fukue Island except in summer; it significantly decreases in summer (18%). Central south China (105°E–123°E, 26°N–34°N) has the relative contribution of 15–30%. The contribution from the Korean Peninsula is estimated at about 10% except in summer. The domestic contribution accounts for about 7% in spring and autumn and increases to 19% in summer. We also estimate the relative contribution to daily average concentration in high PM2.5days (>35 μg m−3). Central north China has a significant contribution of 60–70% except in summer. The relative contribution from central south China is estimated at 46% in summer and about 30% in the other seasons. The contributions from central north and south China on high PM2.5days are generally larger than those of their seasonal mean contributions. The domestic contribution is smaller than the seasonal mean value in every season; it is less than 10% even in summer. These model results suggest that foreign anthropogenic sources have a substantial impact on attainment of the atmospheric environmental standard of Japan at Fukue Island.Implications: The contribution from several source regions in East Asia to PM2.5 concentration at Fukue Island, a remote island located in the western part of Japan and close to the Asian continent, is estimated using a three-dimensional chemical transport model. The model results suggest that PM2.5 that is attributed to foreign anthropogenic sources have a larger contribution than that of domestic pollution and have a substantial impact on attainment of the atmospheric environmental standard of Japan at Fukue Island. [ABSTRACT FROM AUTHOR]

Winter freezing injury is one of the most important factors limiting grapevine production. The main purpose of this study was to investigate the effects of foliar potassium sulphate (K2SO4) fertilisation on the cold-hardiness of 'Bidaneh Sefid' grapevine (Vitis vinifera L.). Four concentrations of potassium sulphate [0.0, 0.5, 1.0, or 2.0% (w/v)] were sprayed to run-off on all leaves of each plant on five occasions at 2-week intervals starting on 11 June 2011. Cane samples were collected on 25 December 2011 and 23 February 2012 and analysed for their carbohydrate, proline, and protein concentrations, then exposed to 3 h freezing treatment between 0°C and -30°C, at intervals of 3°C, to assess their level of cold-hardiness. The results showed that increased K2SO4concentrations resulted in increased carbohydrate, proline, and protein concentrations. The latter increases were greater in cane samples collected in December 2011 than in February 2012, for which the levels of cold-hardiness were also lower. LT50 values (i.e., the lethal temperature at which 50% of tissues died) were estimated by the tetrazolium stain test and by electrolyte leakage measurements. The results indicated that K2SO4 sprays significantly increased cold-hardiness. Significant positive correlations were found between the results of both the tetrazolium stain tests and electrolyte leakage measurements and carbohydrate, proline, and protein concentrations in the cane samples. Compared to the canes, the buds were more vulnerable to cold-injury in December and in February. We conclude that the application of five K2SO4 sprays during the growing season has the capacity to increase the freezing tolerance of grapevine ('Bidaneh Sefid') and could be used as a prophylactic tool to reduce freezing injury during the Winter. [ABSTRACT FROM AUTHOR]

Imbalances in gut microbiota composition during ulcerative colitis (UC) indicate a role for the microbiota in propagating the disorder. Such effects were investigated using in vitro batch cultures (with/without mucin, peptone or starch) inoculated with faecal slurries from healthy or UC patients; the growth of five bacterial groups was monitored along with short-chain fatty acid (SCFA) production. Healthy cultures gave two-fold higher growth and SCFA levels with up to ten-fold higher butyrate production. Starch gave the highest growth and SCFA production (particularly butyrate), indicating starch-enhanced saccharolytic activity. Sulphate-reducing bacteria (SRB) were the predominant bacterial group (of five examined) for UC inocula whereas they were the minority group for the healthy inocula. Furthermore, SRB growth was stimulated by peptone presumably due to the presence of sulphur-rich amino acids. The results suggest raised SRB levels in UC, which could contribute to the condition through release of toxic sulphide. [ABSTRACT FROM AUTHOR]

The solvent extraction of Ti(IV) from sulfate medium by the commercial extractant Cyanex 301 (HA) has been studied in order to examine this novel system. Heptan-1-ol (5% (v/v) in the organic phase) is used as a de-emulsifier. The equilibration time is 45 min. The experimental results suggest that the extracted species is always TiOA2 (o), though the composition of the reacting aqueous Ti(IV) species may vary depending on the concentration levels of Ti(IV), pH, HA and. The equilibrium constant (Kex) at 303 K is measured to be 101.117and 10−1.243for the reaction of monomeric, non-sulfated, mono, and non-hydrolyzed TiO2+, respectively. The effects of heptan-1-ol, temperature, loading, and diluent type have been reported. Stripping can be done effectively by a solution of 1 mol/dm3H2SO4containing 5%(v/v) of “100 volume” H2O2. The possibilities of separation of Ti(IV) from Cu(II), Zn(II), Fe(III), Co(II), and Ni(II) have been predicted. It is proved to be an effective extractant for Ti(IV)/Fe(III) separation from sulphate medium at pH ∼ 1. [ABSTRACT FROM PUBLISHER]

Extraction and separation of divalent Mn and Zn ions from acidic sulfate solutions containing 0.05 M of each metal ion have been carried out using 0.04 M Na-CYANEX 272 in kerosene. The influences of the following parameters were studied: shaking time, equilibrium pH, extractant concentration, diluents type, and temperature. The extraction percentage of both metal ions increased with increasing equilibrium pH in the range 2.0–4.0 and 2.75–6.0 for Zn(II) and Mn(II), respectively. The separation factor, S(Zn/Mn), increases with the increase in pH to reach a maximum value of about 24 × 103at pH 4.0. Extraction of both metal ions increased with increasing extractant concentration. Aliphatic diluents were preferred compared to aromatic diluents. The thermodynamic parameters (ΔH, ΔS, and ΔG) for Mn(II) and Zn(II) were calculated. The extraction mechanism of both metals by Na-CYANEX 272, stripping from loaded extractant and recycling of extractant used in the extraction process were also investigated. [ABSTRACT FROM PUBLISHER]

Laboratory studies of liquid–liquid phase separation in particles containing organic species and inorganic salts of atmospheric relevance are reviewed. The oxygen-to-carbon elemental ratio (O:C) of the organic component appears to be the most useful parameter for estimating, to a first approximation, the occurrence of liquid–liquid phase separation and the separation relative humidity (SRH) in these particles. A trend of decreasing SRH for increasing O:C was found for simple organic–inorganic mixtures (<11 species). Phase separation in particles composed of laboratory-produced secondary organic material and sulphate species and in ambient particles is generally consistent with this trend. A further constraint is that liquid–liquid phase separation was always observed for O:C < 0.5 and was never observed for O:C ≥ 0.8. For organic materials of intermediate O:C ranging from 0.5 to 0.8, phase separation in simple organic–inorganic mixtures was influenced by the organic functional groups represented. The organic-to-inorganic mass ratio (OIR) affected the occurrence of liquid–liquid phase separation in a small number of cases. A dependence on salt type was observed with 87% of the studied organics exhibiting the following trend in SRH values: (NH4)2SO4 ≥ NH4HSO4 ≥ NaCl ≥ NH4NO3, consistent with previous salting-out studies and the Hofmeister series. Liquid–liquid phase separation does not appear to be strongly influenced by the number of species making up the organic material. The morphology of phase separated particles appears to depend on composition, including O:C of the organic material, the inorganic salt and the OIR. [ABSTRACT FROM PUBLISHER]

Bioreduction processes have profound influences on mobility and bioavailability of metals in soils and sediments. In this study, a series of microcosm studies were conducted to investigate bioreduction progresses (ferric iron and sulfate reduction) and their influences on manganese and copper element redistributions with the change of microbial community under various geochemical conditions. Results indicated that ethanol stimulated higher rates of bioreduction processes than acetate did. High-concentration bicarbonate and sulfate addition inhibited iron reduction but not sulfate reduction. Sequential extraction revealed that the exchangeable and carbonate bonding-iron were increased in ethanol amendment, whereas those of copper were decreased. The elevated bicarbonate concentration and sulfate addition both influenced the mobility and redistribution of metals. 16S rRNA analysis indicated that ethanol amendment stimulated the growths of microbial iron and sulfate reducer. A high concentration of bicarbonate suppressed the growth of iron reducerGeobacteraceae, but showed limited effect on sulfate reducers. This study concluded that geochemical conditions such as electron donor, bicarbonate and sulfate concentration influenced the microbial community and led to changes in bioreduction processes and metal distributions in the anerobic sediments. [ABSTRACT FROM PUBLISHER]

Uniform cadmium sulfide (CdS) nanospheres were successfully prepared in the presence of the anionic surfactant sodium dodecylsulfate (SDS) at an appropriate concentration and relatively low temperature. Zeta potential data were collected for the three kinds of CdS particles to verify the existence of the Cd2+counterion on the CdS surface and Charge reversal; this was crucial for the explanation of how the anionic SDS surfactant molecules adsorbed on the negatively charged surface. Moreover, we confirmed that SDS had coated the surface of CdS nanospheres using infrared spectroscopy, and thermogravimetric analysis. An counterion assisted mechanism accounting for synthesis of CdS nanospheres could be widely used in the synthesis of nanomaterials if there is specific adsorption of the counterion. The CdS nanospheres showed good performance for the rapid adsorption of methylene blue. [ABSTRACT FROM AUTHOR]

Scale formation in surface and subsurface oil and gas production equipment has been recognized to be one of the major operational problems. It has also been recognized as a major cause of formation damage either in injection or producing wells. Scale contributes to equipment wear and corrosion and flow restriction, thus resulting in a decrease in oil and gas production. This article presents the amount of strontium sulfate precipitation of formation water, injection water, and mixing of injection water with formation water at different temperatures and pressures. The experimentally measured chemical analyses of formation water and injection water were used by OLI ScaleChem software to determine the amount of strontium sulfate scale formation at different conditions. [ABSTRACT FROM PUBLISHER]

Sulfated zirconia was promoted with alumina and yttria in order to improve catalyst isomerization behaviors. The n-hexane hydroisomerization reaction was carried out in a continuous flow fixed-bed reactor for 80 h on stream to evaluate catalyst reaction stability. The catalyst was characterized by XRD, TGA, H2-TPR, and NH3-TPD technologies in order to investigate the crystalline structure, sulfur content, reduction behavior, and acidity of the catalyst. It was proved that the addition of alumina and yttria obviously increased the sulfur content on the fresh catalyst and also markedly stabilized the sulfur species on the used catalysts. Thus, the modified catalyst possessed the better stable activity and selectivity although the addition of promoter could not enhance the isomerization activity. The crystalline structure of sulfated zirconia, acidity, and sulfur content only showed a limited influence on the isomerization activity of the catalyst. This work would have potential use to prepare an ideal catalyst for a commercial alkane hydroisomerization unit. [ABSTRACT FROM AUTHOR]

The goal of this study was to evaluate the use of passive bioreactors to reduce water-borne plant pathogens (Pythium ultimumandFusarium oxysporum) and nutrient load (NO−3and SO2−4) in greenhouse effluent. Sterilized and unsterilized passive bioreactors filled with a reactive mixture of organic carbon material were used in three replicates. After a startup period of 2 (sterilized) or 5 (unsterilized) weeks, the bioreactor units received for 14 weeks a reconstituted commercial greenhouse effluent composed of 500 mg L−1SO2−4and 300 mg L−1NO−3and were inoculated three times withP. ultimumandF. oxysporum(106CFU mL−1). Efficacy in removing water-borne plant pathogens and nitrate reached 99.9% for both the sterilized and unsterilized bioreactors. However, efficacy in reducing the SO2−4load sharply decreased from 89% to 29% after 2 weeks of NO−3-supply treatment for the unsterilized bioreactors. Although SO2−4removal efficacy for the sterilized bioreactors did not recover after 4 weeks of NO−3-supply treatment, the unsterilized bioreactor nearly reached a similar level of SO2−4removal after 4 weeks of NO−3-supply treatment compared with affluent loaded only with SO2−4, where no competition for the carbohydrate source occurred between the denitrification process and sulfate-reducing bacteria activity. Performance differences between the sterilized and unsterilized bioreactors clearly show the predominant importance of sulfate-reducing bacteria. Consequently, when sulfate-reducing bacteria reach their optimal activity, passive bioreactors may constitute a cheap, low-maintenance method of treating greenhouse effluent to recycle wastewater and eliminate nutrient runoff, which has important environmental impacts. [ABSTRACT FROM AUTHOR]

Density and viscosity of tetrabutyl ammonium hydrogen sulphate and tetrabutyl ammonium chloride in water as well as in methanol have been measured at 303.15 K. Different equations proposed by Einstein, Vand, Moulik and Jones–Dole for viscosity have been applied to the experimental results. An attempt has also been made to study the solute–solute and solute–solvent interactions involved in the system and the effect of anion on cationic surfactant. Molar volumes obtained from Einstein and Vand equations are very close to each other. [ABSTRACT FROM AUTHOR]

The study was aimed at assessing the potential of enzyme-embedded antibiotic-releasing polycaprolactone (PCL)-based electrospun fibres for tunable drug delivery. This was attempted by incorporation of gentamicin sulphate (GS) in the biocompatible polymer (PCL) matrix, with the degradation of the matrix being ensured by co-impregnating a poly-mer-degrading enzyme (lipase). Single phase solutions were obtained by hydrophobic ion pairing of GS and surfactant coating of lipase with an anionic surfactant, docusate sodium salt Aerosol OT (AOT). By electrospinning the solution, we could produce PCL fibres con-taining 11% (w/w) GS-AOT and 28 U (w/w) lipase-AOT. However, sustained release of GS was not obtained. FESEM analysis showed that the fibres did not undergo the expected degradation. Subsequent experiments with unmodified lipase gave satisfactory results; the polymer underwent degradation displaying characteristic perforations in the fibres, sugges-tive of 'endo-attack'. By modulating the concentrations of lipase (1 to 28 U, w/w), we could obtain GS release rates that varied from 0.53 to 32mg/ml/d. Accordingly, the lifetime of the fibres could be tuned (10 h to 25 days). The fibres showed excellent antibacterial activity against Staphylococcus aureus throughout their lifetime. [ABSTRACT FROM AUTHOR]

The influence of initial pH and sulfate concentration on the anaerobic digestion of tannery wastewater was studied using the specific methanogenic activity (SMA) test. The SMA tests were performed with a chemical oxygen demand (COD) concentration of 6.5 g/L and SO−24concentrations of 1.95, 3.90, 6.50, 8.45 and 10.4 g/L. The effect of pH was studied at pH 6.8; 6.4 and 6.1. It was found that methane production took place under all conditions, but the use of SO−24concentrations higher than 8.45 g/L and initial pH levels lower than 6.4 caused a decrease of up to 73% of methane production. The influence of pH was significant only for SO−24concentrations lower than 8.45 g/L, with up to 50% inhibition. Specific methanogenic activity for COD/SO−24ratios lower than 0.77 depends basically on this ratio and not on the initial pH value under the conditions of the study. [ABSTRACT FROM AUTHOR]

This study was carried out from 2003 to 2007 to understand the hydrogeochemical processes and the solute sources of the meltwaters of the Chhota Shigri Glacier, Himalaya. The meltwater is almost neutral to slightly alkaline in nature: bicarbonate and sulphate are the dominant anions, while calcium and magnesium are the dominant cations. Bicarbonate is found to be derived from carbonate weathering and partly from silicate weathering. Rock weathering followed by precipitation are the main controlling factors that influence the meltwater chemistry of this region. The relatively high values of pCO2 reflect a higher rate of solubility in comparison to release of excess CO2 gas to the atmosphere. The presence of active hydrogeochemical processes and sediment–water interaction results in excess solute transport through the meltwater to the Chandra River that feeds the Chenab, one of the great Himalayan river systems, and ultimately flows into the ocean. This study is the first of its kind to understand in detail the hydrogeochemical process and resultant solute load transport in this Himalayan glacier. Citation Sharma, P., Ramanathan, A.L., and Pottakkal, J., 2013. Study of solute sources and evolution of hydrogeochemical processes of the Chhota Shigri Glacier meltwaters, Himachal Himalaya, India. Hydrological Sciences Journal, 58 (5), 1128–1143. Editor Z.W. Kundzewicz [ABSTRACT FROM AUTHOR]

As one kind of the most important intermediate materials in rare earth (RE) industry, RE sulfates have been considered difficult to be extracted and separated directly by saponified extractants due to the dissolubility of RE double sulfate ofcation. By introducing a barrier agent such as Mg2+ion in the present work, we proposed and developed a process to extract RE cations in sulfate medium with saponified HEH(EHP). Further, a selection criterion of the barrier agent was discussed. The results have revealed that the natural distribution of the univalent ion, RE3+and Mg2+ions, as determined by their extraction sequence in the cascade, hinders the contact betweencation and RE ions, and thereby RE double sulfate precipitate does not form during the extraction. Consequently, the study can provide us a strong possibility for extracting and even separating RE using saponified extractants directly from sulfate solution in no need of any transformation of the RE salts employed. [ABSTRACT FROM PUBLISHER]

The purpose of this study is to investigate the impact of precipitant additives, i.e., calcium hydroxide (Ca(OH)2), calcium carbonate (CaCO3) and recycled sludge (RS), on the settling and compacting performance of sludge formed in the process of heavy metal wastewater treatment using bio-polymer ferric sulfate (BPFS). The results show that CaCO3is the most suitable additive since heavy metal removal, sludge settling performance, and compacting performance is improved by 20%, 83.3%, 23.5%, respectively. In addition, scanning electron microscopy and X-ray diffraction were measured for contrasting the sludge morphology and crystallinity. The results suggest that CaCO3acted as seeding material produces the largest flocs. Moreover, the flocculation theory combined with zeta potential measurement was used to explain the sludge formation mechanism, which is proposed as charge neutralization by BPFS, sweep flocculation by amorphous precipitate, and bridging flocculation by polyacrylamide (PAM) in sequence. The improvement of sludge properties by adding CaCO3benefits from the enhancement of sweep flocculation. In summary, the interaction mechanism between precipitant additives and sludge performance is well understood, thus providing useful information about adding precipitant additives to improve both the sludge settling properties and the quality of the treated water during the heavy metal wastewater treatment. [ABSTRACT FROM PUBLISHER]

Voltammetry, electrochemical impedance spectroscopy, SEM and XRD techniques were applied to study tin plating in acid 0·01M Sn(II) solutions containing different amounts (0·02-0·1M) of gluconate and 0·5M Na2SO4. Solution pH is the main factor that governs the rate of Sn(II) reduction. An increase in pH from 2 to 5 results in a 100-fold growth in electrode impedance and a four-fold reduction in limiting current density. Spongy tin deposits are obtained in the ligand insufficient solutions at low cathodic polarisations ΔE. To obtain compact fine grained tin coatings, ΔE and/or the gluconate concentration should be correspondingly increased. Sn(II) reduction proceeds under conditions of strong inhibition involving destructive ligand chemisorption and incorporation of its fragments into deposits. [ABSTRACT FROM AUTHOR]

The study highlights the role of sulfur (S) in detoxification of arsenate-induced toxicity and the shift in essential element homeostasis inZea maysL (SRHM 445). Overall growth of arsenate-treated plants under sulfur starvation (−S) was lower than that in the presence of excess sulfur (+S). Translocation of arsenate from roots to shoots, increased under As(−S) and decreased with As(+S). The level of micronutrients (Cu, Zn, Fe) increased in As(−S) plants. Whereas, the level of K and PO4was higher in As(−S) plants than in As(+S) plants. Higher malondialdehyde, protein carbonyl, and H2O2levels in As(−S) plants are indicative of higher oxidative stress. Higher superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities, in As(−S) plants coincided with higher H2O2levels showing the activity of these enzymes are independent of S availability. Absence of reduced glutathione/oxidized glutathione pool in (−S) plants manifested into failure of ascorbate–glutathione detoxification pathway. Hence, S has dual role of protecting the plant against arsenate-induced toxicity (1) by restricting arsenic (As) translocation to the upper parts and (2) by increasing the activity SOD and APX. [ABSTRACT FROM AUTHOR]