The kinetics of hydrogen removal from liquid sodium

International Nuclear Information System (INIS)

Gwyther, J.R.; Whittingham, A.C.

1981-01-01

The rates of hydrogen removal from liquid sodium-sodium hydride mixtures have been measured as a function of sodium stirring rate at temperatures up to 420 0 C. Two techniques have been employed - removal under continuous evacuation in which hydrogen flow rates were measured using a capillary flow technique and by argon purging in which hydrogen concentrations in the argon carrier gas were measured by gas chromatography. The results have been used to assess the feasibility of thermal decomposition of sodium hydride for the regeneration of hydride-laden LMFBR cold traps. Studies on the kinetics of desorption of hydrogen from solution in liquid sodium at temperatures up to 400 0 C are also presented and possible kinetic mechanisms discussed. (orig.)

Profile of irritant patch testing with detergents: sodium lauryl sulfate, sodium laureth sulfate and alkyl polyglucoside.

Science.gov (United States)

Löffler, H; Happle, R

2003-01-01

The cutaneous reaction to detergents follows distinct kinetic rules: the duration of application and the irritant concentration are of major importance. The aim of this study was to evaluate the differences in kinetics of skin reaction between the standard irritant sodium lauryl sulfate (SLS), and 2 modern detergents: sodium laureth sulfate (SLES) and alkyl polyglucoside (APG). We performed patch testing with SLS and SLES (or APG) at different concentrations (0.125, 0.25, 0.5, 1.0 and 2.0%) and with different exposure times (6, 12 and 24 h). Evaluation was conducted by measurement of transepidermal water loss (TEWL) and laser Doppler flowmetry (LD) 24 h, 7 and 10 days after patch removal. We found a pronounced reaction to SLS, and a far milder one to SLES. Even at the highest concentration the skin reaction to APG was hard to detect. During the regeneration period (day 3-10) SLS showed even at day 10 an increased TEWL at all concentrations tested. The irritation due to SLES was convincingly detectable only up to day 7, whereas the APG-tested skin areas showed no significant reaction even at day 3. These results demonstrate the improvement in reduction of skin irritation achieved by development of novel detergents.

Sodium hydrazinidoborane: a chemical hydrogen-storage material.

Science.gov (United States)

Moury, Romain; Demirci, Umit B; Ichikawa, Takayuki; Filinchuk, Yaroslav; Chiriac, Rodica; van der Lee, Arie; Miele, Philippe

2013-04-01

Herein, we present the successful synthesis and full characterization (by (11) B magic-angle-spinning nuclear magnetic resonance spectroscopy, infrared spectroscopy, powder X-ray diffraction) of sodium hydrazinidoborane (NaN2 H3 BH3 , with a hydrogen content of 8.85 wt %), a new material for chemical hydrogen storage. Using lab-prepared pure hydrazine borane (N2 H4 BH3 ) and commercial sodium hydride as precursors, sodium hydrazinidoborane was synthesized by ball-milling at low temperature (-30 °C) under an argon atmosphere. Its thermal stability was assessed by thermogravimetric analysis and differential scanning calorimetry. It was found that under heating sodium hydrazinidoborane starts to liberate hydrogen below 60 °C. Within the range of 60-150 °C, the overall mass loss is as high as 7.6 wt %. Relative to the parent N2 H4 BH3 , sodium hydrazinidoborane shows improved dehydrogenation properties, further confirmed by dehydrogenation experiments under prolonged heating at constant temperatures of 80, 90, 95, 100, and 110 °C. Hence, sodium hydrazinidoborane appears to be more suitable for chemical hydrogen storage than N2 H4 BH3 . Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bacteria and Acidic Drainage from Coal Refuse: Inhibition by Sodium Lauryl Sulfate and Sodium Benzoate

OpenAIRE

Dugan, Patrick R.; Apel, William A.

1983-01-01

The application of an aqueous solution of sodium lauryl sulfate and sodium benzoate to the surface of high-sulfur coal refuse resulted in the inhibition of iron-and sulfur-oxidizing chemoautotrophic bacteria and in the decrease of acidic drainage from the refuse, suggesting that acid drainage can be abated in the field by inhibiting iron- and sulfur-oxidizing bacteria.

The influence of sodium salts (iodide, chloride and sulfate) on the formation efficiency of sulfamerazine nanocrystals.

Science.gov (United States)

Lou, Hao; Liu, Min; Qu, Wen; Johnson, James; Brunson, Ed; Almoazen, Hassan

2014-08-01

The purpose of this study is to evaluate the influence of sodium iodide, sodium chloride and sodium sulfate on the formation efficiency of sulfamerazine nanocrystals by wet ball milling. Sulfamerazine was milled using zirconium oxide beads in a solution containing polyvinylpyrrolidone (PVP) and a sodium salt (iodide, chloride or sulfate). Particle size distributions were evaluated by light diffraction before and after milling. High-performance liquid chromatography was utilized to determine the amount of PVP adsorbed onto sulfamerazine surface. Lyophilized nanocrystals were further characterized by differential scanning calorimetry and dissolution testing. Sulfate ion had more profound effect on reducing particle size via milling than iodide or chloride. We linked our findings to Hofmeister ion series, which indicates that sulfate ions tends to break the water structure, increases the surface tension and lowers the solubility of hydrocarbons in water. We hypothesized that the addition of sulfate ions dehydrated the PVP molecules and enhanced its adsorption onto the sulfamerazine particle surfaces. Consequently, the adsorbed PVP helped to stabilize of the nanosuspension. The nanocrystals that were obtained from the lyophilized milled suspensions exhibited a notable increase in dissolution rate. The addition of sodium sulfate enhanced the formation efficiency of sulfamerazine nanocrystals.

Dextran sulfate sodium-induced colitis in piglets

DEFF Research Database (Denmark)

Nielsen, Katrine Dalby; Schramm, Andreas; Purup, Stig

Inflammatory bowel disease (IBD) results from complex interactions between genetic and environmental factors. Although a genetic contribution has been proven, dietary factors have also shown to play a role in the development of IBD. This study aims to investigate the effect of adding red meatto t...... the diet of piglets in a dextran sodium sulfate (DSS)-induced colitis model....

Bacteria and Acidic Drainage from Coal Refuse: Inhibition by Sodium Lauryl Sulfate and Sodium Benzoate

Science.gov (United States)

Dugan, Patrick R.; Apel, William A.

1983-01-01

The application of an aqueous solution of sodium lauryl sulfate and sodium benzoate to the surface of high-sulfur coal refuse resulted in the inhibition of iron-and sulfur-oxidizing chemoautotrophic bacteria and in the decrease of acidic drainage from the refuse, suggesting that acid drainage can be abated in the field by inhibiting iron- and sulfur-oxidizing bacteria. PMID:16346347

Improving the Corrosion Inhibitive Strength of Sodium Sulphite in Hydrogen Cyanide Solution Using Sodium Benzoate

Directory of Open Access Journals (Sweden)

Muhammed Olawale Hakeem AMUDA

2008-12-01

Full Text Available The improvement in the inhibitive strength of sodium sulphite on corrosion of mild steel in hydrogen cyanide by adding sodium benzoate in regulated volume was investigated using the fundamental weight loss measurement.500 ppm concentration inhibitive mixtures of sodium benzoate and sodium sulphite in three different volume ratios (5/15, 10/10, 15/5 were formulated and studied for corrosion rate in 200ml hydrogen cyanide fluid. Result obtained indicates that the corrosion rate of mild steel in hydrogen cyanide in the presence of sodium benzoate/sodium sulphite inhibitive mixtures range 0.322mmpy to 1.1269mmpy across the three volumetric ratios considered. The 15ml5ml sodium benzoatesodium sulphite mixture had the best average corrosion rate of 0.5123mmpy.The corrosion rate followed reducing pattern after the first 200 hours of immersion. The average corrosion rate in the sodium benzoate / sodium sulphite mixture is less than the rate in sodium sulphite and the mixture is only effective after long time exposure.It is concluded that adding sodium benzoate to sodium sulphite in the volumetric ratio 155ml improves the inhibitive strength of sodium sulphite on the corrosion of mild steel in hydrogen cyanide environment.

An electrochemical hydrogen meter for measuring hydrogen in sodium using a ternary electrolyte mixture

CERN Document Server

Sridharan, R; Nagaraj, S; Gnanasekaran, T; Periaswami, G

2003-01-01

An electrochemical sensor for measuring hydrogen concentration in liquid sodium that is based on a ternary mixture of LiCl, CaCl sub 2 and CaHCl as the electrolyte has been developed. DSC experiments showed the eutectic temperature of this ternary system to be approx 725 K. Impedance spectroscopic analysis of the electrolyte indicated ionic conduction through a molten phase at approx 725 K. Two electrochemical hydrogen sensors were constructed using the ternary electrolyte of composition 70 mol% LiCl:16 mol% CaHCl:14 mol% CaCl sub 2 and tested at 723 K in a mini sodium loop and at hydrogen levels of 60-250 ppb in sodium. The sensors show linear response in this concentration range and are capable of detecting a change of 10 ppb hydrogen in sodium over a background level of 60 ppb. Identification of this electrolyte system and its use in a sensor for measuring hydrogen in sodium are described in this paper.

The electrical and thermal properties of sodium sulfate mixed with lithium sulfate, yttrium sulfate, and silicon dioxide

International Nuclear Information System (INIS)

Imanaka, N.; Yamaguchi, Y.; Adachi, G.; Shiokawa, J.

1986-01-01

Sodium sulfate mixed with lithium sulfate, yttrium sulfate, and silicon dioxide was prepared. The thermal and electrical properties of its phases were investigated. The Na 2 SO 4 -Li 2 SO 4 -Y 2 (SO 4 ) 3 SiO 2 samples are similar to the Na 2 SO 4 -I phase (a high temperature phase), which is appreciably effective for Na + ionic conduction. Phase transformation was considerably suppressed by mixing. Electromotive force (EMF) was measured, using Na 2 SO 4 -Li 2 SO 4 -Y 2 (SO 4 ) 3 -SiO 2 as a solid electrolyte, by constructing an SO 2 gas concentration cell. The measured EMF's at 823 and 773 K were in fairly good accordance with the calculated EMF's for inlet SO 2 gas concentration between 30 ppm and 1%, and 500 ppm and 0.5% respectively

Hydrogen detector for sodium cooled reactors

International Nuclear Information System (INIS)

Roy, P.; Rodgers, D.N.

1975-01-01

An improved hydrogen detector for use in sodium cooled reactors is described. The improved detector basically comprises a diffusion tube of either pure nickel or stainless steel having a coating on the vacuum side (inside) of a thin layer of refractory metal, e.g., tungsten or molybdenum. The refractory metal functions as a diffusion barrier in the path of hydrogen diffusing from the sodium on the outside of the detector into the vacuum on the inside, thus by adjusting the thickness of the coating, it is possible to control the rate of permeation of hydrogen through the tube, thereby providing a more stable detector. (U.S.)

Biogeochemistry of molecular hydrogen in sulfate-reducing sediments

Energy Technology Data Exchange (ETDEWEB)

Novelli, P.C.

1987-01-01

Concentrations of molecular hydrogen (H{sub 2}) have been measured using an equilibration-vacuum transfer method coupled to mercuric oxide reduction. In hemipelagic sediments (Eastern Tropical North Pacific (ETNP)) and bioturbated sediments (Princess Louisa Inlet, BC (PLI), and Buzzards Bay, MA (BB)) hydrogen levels were lowest in surface sediments and increased with depth. Sharp increases in H{sub 2} concentrations were observed just below the zone of bioturbation (PLI and BB), or below the depth of nitrate depletion (ETNP). Apparent hydrogen production rates were determined in laboratory incubations of sediments amended with inhibitors of sulfate reduction and methanogenesis. Hydrogen production ranged from 30 nmol 1{sup {minus}1} h{sup {minus}1} to 20 {times} 10{sup 3} nmol 1{sup {minus}1} h{sup {minus}1}. Apparent hydrogen production rates generally decreased in parallel with measured sulfate reduction rates. Experiments examined the response of apparent H{sub 2} production rates to additions of both specific organic chemicals and to additions of naturally occurring, complex organic materials. Organic sources typically considered labile (sucrose, and algae) stimulated apparent production up to a factor of 70. More refractory compounds (humic acids, chitin), stimulated rates of hydrogen production only slightly or not at all. These results show that hydrogen production is, in part, a function of the type of organic matter being degraded.

Economical Aspects of Sodium Borohydride for Hydrogen Storage

International Nuclear Information System (INIS)

Ture, I. Engin; Tabakoglu, F. Oznur; Kurtulus, Gulbahar

2006-01-01

Hydrogen is the best fuel among others, which can minimize the cause to global warming. Turkey has an important location with respect to hydrogen energy applications. Moreover, Turkey has 72.2% of the world's total boron reserves. Sodium borohydride (NaBH 4 ) which can be produced from borax has high hydrogen storage capacity. Hence, it is important for Turkey to lead studies about sodium borohydride to make it one of the most feasible hydrogen storage methods. In this paper an approximate process cost analysis of a NaBH 4 -H 2 system is given, starting with NaBH 4 production till recycling of it. It is found that, the usage of NaBH 4 as hydrogen storage material is relatively an expensive method but after improving reactions and by-product removal in the system and reducing the energy and reactant costs, sodium borohydride is one of the best candidates among hydrogen storage technologies. (authors)

Analysis of sperm antigens by sodium dodecyl sulfate gel/protein blot radioimmunobinding method

International Nuclear Information System (INIS)

Lee, C.Y.G.; Huang, Y.S.; Hu, P.C.; Gomel, V.; Menge, A.C.

1982-01-01

A radioimmunobinding method based on the blotting of renatured proteins from sodium dodecyl sulfate gels on to nitrocellulose filter papers was developed to analyze the sperm antigens that elicit serum anti-sperm antibodies. In rabbits, serum anti-sperm antibodies were raised by immunization with homologous epididymal spermatozoa mixed with complete Freund's adjuvant. The raised antisera from either male or female rabbits were shown to react with three major sperm protein bands on sodium dodecyl sulfate gels with the corresponding molecular weights of about 70,000 +/- 5000, 14,000, and 13,000, respectively. In humans, the monoclonal antibodies against human sperm were raised by a hybridoma technique. Out of six independent hybrid cell lines that were generated, three of them were shown to secrete immunoglobulins that react with the same two protein bands on sodium dodecyl sulfate gels, which have the approximate molecular weight of 10,000. The same procedure was also used to analyze human serum samples that were shown to contain anti-sperm antibodies by the known techniques. Unique sperm antigens that elicit anti-sperm antibodies in humans were identified and correlated. The results of this study suggest that sodium dodecyl sulfate gel/protein blot radioimmunobinding method may be a sensitive and useful tool for the study of sperm antigens that elicit autoimmune responses and their association with human infertility

Sodium Borohydride/Hydrogen Peroxide Fuel Cells For Space Application

Science.gov (United States)

Valdez, T. I.; Deelo, M. E.; Narayanan, S. R.

2006-01-01

This viewgraph presentation examines Sodium Borohydride and Hydrogen Peroxide Fuel Cells as they are applied to space applications. The topics include: 1) Motivation; 2) The Sodium Borohydride Fuel Cell; 3) Sodium Borohydride Fuel Cell Test Stands; 4) Fuel Cell Comparisons; 5) MEA Performance; 6) Anode Polarization; and 7) Electrode Analysis. The benefits of hydrogen peroxide as an oxidant and benefits of sodium borohydride as a fuel are also addressed.

Hydrogen generation systems utilizing sodium silicide and sodium silica gel materials

Science.gov (United States)

Wallace, Andrew P.; Melack, John M.; Lefenfeld, Michael

2015-07-14

Systems, devices, and methods combine reactant materials and aqueous solutions to generate hydrogen. The reactant materials can sodium silicide or sodium silica gel. The hydrogen generation devices are used in fuels cells and other industrial applications. One system combines cooling, pumping, water storage, and other devices to sense and control reactions between reactant materials and aqueous solutions to generate hydrogen. Multiple inlets of varied placement geometries deliver aqueous solution to the reaction. The reactant materials and aqueous solution are churned to control the state of the reaction. The aqueous solution can be recycled and returned to the reaction. One system operates over a range of temperatures and pressures and includes a hydrogen separator, a heat removal mechanism, and state of reaction control devices. The systems, devices, and methods of generating hydrogen provide thermally stable solids, near-instant reaction with the aqueous solutions, and a non-toxic liquid by-product.

Activation of Recombinantly Expressed l-Amino Acid Oxidase from Rhizoctonia solani by Sodium Dodecyl Sulfate

Directory of Open Access Journals (Sweden)

Katharina Hahn

2017-12-01

Full Text Available l-Amino acid oxidases (l-AAO catalyze the oxidative deamination of l-amino acids to the corresponding α-keto acids. The non-covalently bound cofactor FAD is reoxidized by oxygen under formation of hydrogen peroxide. We expressed an active l-AAO from the fungus Rhizoctonia solani as a fusion protein in E. coli. Treatment with small amounts of the detergent sodium dodecyl sulfate (SDS stimulated the activity of the enzyme strongly. Here, we investigated whether other detergents and amphiphilic molecules activate 9His-rsLAAO1. We found that 9His-rsLAAO1 was also activated by sodium tetradecyl sulfate. Other detergents and fatty acids were not effective. Moreover, effects of SDS on the oligomerization state and the protein structure were analyzed. Native and SDS-activated 9His-rsLAAO1 behaved as dimers by size-exclusion chromatography. SDS treatment induced an increase in hydrodynamic radius as observed by size-exclusion chromatography and dynamic light scattering. The activated enzyme showed accelerated thermal inactivation and an exposure of additional protease sites. Changes in tryptophan fluorescence point to a more hydrophilic environment. Moreover, FAD fluorescence increased and a lower concentration of sulfites was sufficient to form adducts with FAD. Taken together, these data point towards a more open conformation of SDS-activated l-amino acid oxidase facilitating access to the active site.

Effect of pH and sulfate concentration on hydrogen production using anaerobic mixed microflora

Energy Technology Data Exchange (ETDEWEB)

Hwang, Jae-Hoon; Choi, Jeong-A.; Bhatnagar, Amit; Kumar, Eva; Jeon, Byong-Hun [Department of Environmental Engineering, Yonsei University, Wonju, Gangwon-do, 220-710 (Korea); Abou-Shanab, R.A.I. [Department of Environmental Engineering, Yonsei University, Wonju, Gangwon-do, 220-710 (Korea); Department of Environmental Biotechnology, Mubarak City for Scientific Research, Alexandria (Egypt); Min, Booki [Department of Environmental Science and Engineering, Kyung Hee University, Yongin-Si, Gyeonggi-Do 446-701 (Korea); Song, Hocheol; Kim, Yong Je [Geologic Environment Division, KIGAM, Daejeon, 305-350 (Korea); Choi, Jaeyoung [Korea Institute of Science and Technology (KIST), Gangneung Institute, Gangneung 210-340 (Korea); Lee, Eung Seok [Geological Sciences, College of Arts and Sciences, Ohio University, Athens, OH 45701-2979 (United States); Um, Sukkee [School of Mechanical Engineering, Hanyang University, 17 Haengdang-Dong, Seongdong-Gu, Seoul, 133-791 (Korea); Lee, Dae Sung [Petroleum and Marine Research Department, KIGAM, Daejeon (Korea)

2009-12-15

The effects of varying sulfate concentrations with pH on continuous fermentative hydrogen production were studied using anaerobic mixed cultures growing on a glucose substrate in a chemostat reactor. The maximum hydrogen production rate was 2.8 L/day at pH 5.5 and sulfate concentration of 3000 mg/L. Hydrogen production and residual sulfate level decreased with increasing the pH from 5.5 to 6.2. The volatile fatty acids (VFAs) and ethanol fractions in the effluent were in the order of butyric acid (HBu) > acetic acid (HAc) > ethanol > propionic acid (HPr). Fluorescence In Situ Hybridization (FISH) analysis revealed the presence of hydrogen producing bacteria (HPB) under all pH ranges while sulfate reducing bacteria (SRB) were present at pH 5.8 and 6.2. The inhibition in hydrogen production by SRB at pH 6.2 diminished entirely by lowering to pH 5.5, at which activity of SRB is substantially suppressed. (author)

Understanding the kinetics of sulfate reduction in brines by hydrogen: Progress report

International Nuclear Information System (INIS)

Strachan, D.M.

1988-07-01

Experiments were conducted with mixtures of hydrogen gas and each of PBB1 and PBB3 brines to examine the reduction kinetics of sulfate in high ionic strength solutions. Results from the experiments with brines showed that the kinetics of sulfate reduction is slower in high ionic strength solutions than the kinetics in low ionic strength solutions. However, the kinetic mechanism does not seem to alter the slow kinetics, but the addition of much larger quantities of sulfide, about 40 mM, does accelerate the reduction of sulfate. Since the proposed reaction mechanism for the reduction of sulfate by hydrogen gas involves the reaction of sulfide with sulfate, slow initial kinetics in the absence of sulfide is understandable, but also implies an unknown rate-limiting reaction. Precipitation of calcium sulfate(s) and calcium sulfide may limit the sulfide and sulfate concentrations to low values. The coexistence of anhydrite and oldhamite may indicate a part of the Ca-S-H 2 O that has not yet been investigated. 6 refs., 4 figs., 3 tabs

Time-resolved fluorescence quenching studies of sodium lauryl ether sulfate micelles

International Nuclear Information System (INIS)

Friedrich, Leidi C.; Silva, Volnir O.; Quina, Frank H.; Moreira Junior, Paulo F.; Tcacenco, Celize M.

2013-01-01

Aggregation numbers (N Ag ) of micelles of the commercial anionic detergent sodium lauryl ether sulfate (SLES), with an average of two ethylene oxide subunits, were determined at 30 and 40 deg C by the time-resolved fluorescence quenching method with pyrene as the fluorescent probe and the N-hexadecylpyridinium ion as the quencher. The added-salt dependent growth of SLES micelles (γ = 0.11-0.15, where γ is the slope of a plot of log aggregation number vs. log [Y aq ] and [Y aq ] is the sodium counterion concentration free in the intermicellar aqueous phase) is found to be significantly lower than that of sodium alkyl sulfate micelles (γ ca. 0.25), a difference attributed to the larger headgroup size of SLES. The I 1 /I 3 vibronic intensity ratio and the rate constant for intramicellar quenching of pyrene show that the pyrene solubilization microenvironment and the intramicellar microviscosity are insensitive to micelle size or the presence of added salt. (author)

Time-resolved fluorescence quenching studies of sodium lauryl ether sulfate micelles

Energy Technology Data Exchange (ETDEWEB)

Friedrich, Leidi C.; Silva, Volnir O.; Quina, Frank H., E-mail: quina@usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Instituto de Quimica; Moreira Junior, Paulo F. [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Escola Politecnica. Departamento de Engenharia Quimica; Tcacenco, Celize M. [Fundacao Instituto de Ensino para Osasco (FIEO/UNIFIEO), SP (Brazil). Centro Universitario FIEO. Centro de Estudos Quimicos

2013-02-15

Aggregation numbers (N{sub Ag}) of micelles of the commercial anionic detergent sodium lauryl ether sulfate (SLES), with an average of two ethylene oxide subunits, were determined at 30 and 40 deg C by the time-resolved fluorescence quenching method with pyrene as the fluorescent probe and the N-hexadecylpyridinium ion as the quencher. The added-salt dependent growth of SLES micelles ({gamma} = 0.11-0.15, where {gamma} is the slope of a plot of log aggregation number vs. log [Y{sub aq}] and [Y{sub aq}] is the sodium counterion concentration free in the intermicellar aqueous phase) is found to be significantly lower than that of sodium alkyl sulfate micelles ({gamma} ca. 0.25), a difference attributed to the larger headgroup size of SLES. The I{sub 1}/I{sub 3} vibronic intensity ratio and the rate constant for intramicellar quenching of pyrene show that the pyrene solubilization microenvironment and the intramicellar microviscosity are insensitive to micelle size or the presence of added salt. (author)

Improving the Corrosion Inhibitive Strength of Sodium Sulphite in Hydrogen Cyanide Solution Using Sodium Benzoate

OpenAIRE

Muhammed Olawale Hakeem AMUDA; Olusegun Olusoji SOREMEKUN; Olakunle Wasiu SUBAIR; Atinuke OLADOYE

2008-01-01

The improvement in the inhibitive strength of sodium sulphite on corrosion of mild steel in hydrogen cyanide by adding sodium benzoate in regulated volume was investigated using the fundamental weight loss measurement.500 ppm concentration inhibitive mixtures of sodium benzoate and sodium sulphite in three different volume ratios (5/15, 10/10, 15/5) were formulated and studied for corrosion rate in 200ml hydrogen cyanide fluid. Result obtained indicates that the corrosion rate of mild steel i...

Decellularized Rat Lung Scaffolds Using Sodium Lauryl Ether Sulfate for Tissue Engineering.

Science.gov (United States)

Ma, Jinhui; Ju, Zhihai; Yu, Jie; Qiao, Yeru; Hou, Chenwei; Wang, Chen; Hei, Feilong

Perfusion decellularization with detergents is effective to maintain the architecture and proteins of extracellular matrix (ECM) for use in the field of lung tissue engineering (LTE). However, it is unclear which detergent is ideal to produce an acellular lung scaffold. In this study, we obtained two decellularized rat lung scaffolds using a novel detergent sodium lauryl ether sulfate (SLES) and a conventional detergent sodium dodecyl sulfate (SDS). Both decellularized lung scaffolds were assessed by histology, immunohistochemistry, scanning electron microscopy, DNA quantification, sulfated glycosaminoglycans (GAGs) quantification and western blot. Subsequently, the scaffolds were implanted subcutaneously in rats for 6 weeks and were evaluated via hematoxylin and eosin staining and Masson staining. Results indicated that SLES was effective to remove cells; moreover, lungs decellularized with SLES showed better preservation of sulfated GAGs, lung architecture, and ECM proteins than SDS. After 6 weeks, SLES scaffolds demonstrated a significantly greater potential for cell infiltration and blood vessel formation compared with SDS scaffolds. Taken together, we conclude that SLES is a promising detergent to produce an acellular scaffold using LTE for eventual transplantation.

Hydrophobic interactions between polymethacrylic acid and sodium laureth sulfate in aqueous solutions

Science.gov (United States)

Yaremko, Z. M.; Fedushinskaya, L. B.; Burka, O. A.; Soltys, M. N.

2014-09-01

The role of hydrophobic interaction in the development of associative processes is demonstrated, based on the concentration dependences of the viscosity and pH of binary solutions of polymethacrylic acid as an anionic polyelectrolyte and sodium laureth sulfate as an anionic surfactant. It is found that the inflection point on the dependence of the difference between the pH values of binary solutions of polymethacrylic acid and sodium laureth sulfate on the polyelectrolyte concentration is a criterion for determining the predominant contribution from hydrophobic interaction, as is the inflection point on the dependence of pH of individual solutions of polymethacrylic acid on the polyelectrolyte concentration.

Pathway of Fermentative Hydrogen Production by Sulfate-reducing Bacteria

Energy Technology Data Exchange (ETDEWEB)

Wall, Judy D. [Univ. of Missouri, Columbia, MO (United States)

2015-02-16

Biofuels are a promising source of sustainable energy. Such biofuels are intermediate products of microbial metabolism of renewable substrates, in particular, plant biomass. Not only are alcohols and solvents produced in this degradative process but energy-rich hydrogen as well. Non photosynthetic microbial hydrogen generation from compounds other than sugars has not been fully explored. We propose to examine the capacity of the abundant soil anaerobes, sulfate-reducing bacteria, for hydrogen generation from organic acids. These apparently simple pathways have yet to be clearly established. Information obtained may facilitate the exploitation of other microbes not yet readily examined by molecular tools. Identification of the flexibility of the metabolic processes to channel reductant to hydrogen will be useful in consideration of practical applications. Because the tools for genetic and molecular manipulation of sulfate-reducing bacteria of the genus Desulfovibrio are developed, our efforts will focus on two strains, D. vulgaris Hildenborough and Desulfovibrio G20.Therefore total metabolism, flux through the pathways, and regulation are likely to be limiting factors which we can elucidate in the following experiments.

Comparative study on the mechanisms of rotavirus inactivation by sodium dodecyl sulfate and ethylenediaminetetraacetate

Energy Technology Data Exchange (ETDEWEB)

Ward, R.L. (Sandia Labs., Albuquerque, NM); Ashley, C.S.

1980-06-01

This report describes a comparative study on the effects of the anionic detergent sodium dodecyl sulfate and the chelating agent ethylenediaminetetraacetate on purified rotavirus SA-11 particles. Both chemicals readily inactivated rotavirus at quite low concentrations and under very mild conditions. In addition, both agents modified the viral capsid and prevented the adsorption of inactivated virions to cells. Capsid damage by ethylenediaminetetraacetate caused a shift in the densities of rotavirions from about l.35 to about 1.37 g/ml and a reduction in their sedimentation coefficients. Sodium dodcyl sulfate, on the other hand, did not detectably alter either of these physical properties of rotavirions. Both agents caused some alteration of the isoelectric points of the virions. Finally, analysis of rotavirus proteins showed that ethylenediaminetetraacetate caused the loss of two protein peaks from the electrophoretic pattern of virions but sodium dodecyl sulfate caused the loss of only one of these same protein peaks.

Development of hydrogen storage systems using sodium alanate

Energy Technology Data Exchange (ETDEWEB)

Lozano Martinez, Gustavo Adolfo

2010-12-06

In this work, hydrogen storage systems based on sodium alanate were studied, modelled and optimised, using both experimental and theoretical approaches. The experimental approach covered investigations of the material from mg scale up to kg scale in demonstration test tanks, while the theoretical approach discussed modelling and simulation of the hydrogen sorption process in a hydride bed. Both approaches demonstrated the strong effect of heat transfer on the sorption behaviour of the hydride bed and led to feasible methods to improve and optimise the volumetric and gravimetric capacities of hydrogen storage systems. The applied approaches aimed at an optimal integration of sodium alanate material in practical hydrogen storage systems. First, it was experimentally shown that the size of the hydride bed influences the hydrogen sorption behaviour of the material. This is explained by the different temperature profiles that are developed inside the hydride bed during the sorptions. In addition, in a self-constructed cell it was possible to follow the hydrogen sorptions and the developed temperature profiles within the bed. Moreover, the effective thermal conductivity of the material was estimated in-situ in this cell, given very good agreement with reported values of ex-situ measurements. It was demonstrated that the effective thermal conductivity of the hydride bed can be enhanced by the addition of expanded graphite. This enhancement promotes lower temperature peaks during the sorptions due to faster heat conduction through the bed, which in addition allows faster heat transfer during sorption. Looking towards simulations and further evaluations, empirical kinetic models for both hydrogen absorption and desorption of doped sodium alanate were developed. Based on the results of the model, the optimal theoretical pressure-temperature conditions for hydrogen sorptions were determined. A new approach is proposed for the mass balance of the reactions when implementing

Sodium lauryl ether sulfate (SLES) degradation by nitrate-reducing bacteria

NARCIS (Netherlands)

Silva Paulo, da Ana; Aydin, Rozelin; Dimitrov, Mauricio R.; Vreeling, Harm; Cavaleiro, Ana J.; García-Encina, Pedro A.; Stams, Fons; Plugge, Caroline M.

2017-01-01

The surfactant sodium lauryl ether sulfate (SLES) is widely used in the composition of detergents and frequently ends up in wastewater treatment plants (WWTPs). While aerobic SLES degradation is well studied, little is known about the fate of this compound in anoxic environments, such as

Effects of enteral and intravenous fluid therapy, magnesium sulfate, and sodium sulfate on colonic contents and feces in horses.

Science.gov (United States)

Lopes, Marco A F; White, Nathaniel A; Donaldson, Lydia; Crisman, Mark V; Ward, Daniel L

2004-05-01

To assess changes in systemic hydration, concentrations of electrolytes in plasma, hydration of colonic contents and feces, and gastrointestinal transit in horses treated with IV fluid therapy or enteral administration of magnesium sulfate (MgSO4), sodium sulfate (NaSO4), water, or a balanced electrolyte solution. 7 horses with fistulas in the right dorsal colon (RDC). In a crossover design, horses alternately received 1 of 6 treatments: no treatment (control); IV fluid therapy with lactated Ringer's solution; or enteral administration of MgSO4, Na2SO4, water, or a balanced electrolyte solution via nasogastric intubation. Physical examinations were performed and samples of blood, RDC contents, and feces were collected every 6 hours during the 48 hour-observation period. Horses were muzzled for the initial 24 hours but had access to water ad libitum. Horses had access to hay, salt, and water ad libitum for the last 24 hours. Enteral administration of a balanced electrolyte solution and Na2SO4 were the best treatments for promoting hydration of RDC contents, followed by water. Sodium sulfate was the best treatment for promoting fecal hydration, followed by MgSO4 and the balanced electrolyte solution. Sodium sulfate caused hypocalcemia and hypernatremia, and water caused hyponatremia. Enteral administration of a balanced electrolyte solution promoted hydration of RDC contents and may be useful in horses with large colon impactions. Enteral administration of either Na2SO4 or water may promote hydration of RDC contents but can cause severe electrolyte imbalances.

Fractionation of hydrogen isotopes by sulfate- and nitrate-reducing bacteria

Directory of Open Access Journals (Sweden)

Magdalena Rose Osburn

2016-08-01

Full Text Available Hydrogen atoms from water and food are incorporated into biomass during cellular metabolism and biosynthesis, fractionating the isotopes of hydrogen –protium and deuterium –that are recorded in biomolecules. While these fractionations are often relatively constant in plants, large variations in the magnitude of fractionation are observed for many heterotrophic microbes utilizing different central metabolic pathways. The correlation between metabolism and lipid δ2H provides a potential basis for reconstructing environmental and ecological parameters, but the calibration dataset has thus far been limited mainly to aerobes. Here we report on the hydrogen isotopic fractionations of lipids produced by nitrate-respiring and sulfate-reducing bacteria. We observe only small differences in fractionation between oxygen- and nitrate-respiring growth conditions, with a typical pattern of variation between substrates that is broadly consistent with previously described trends. In contrast, fractionation by sulfate-reducing bacteria does not vary significantly between different substrates, even when autotrophic and heterotrophic growth conditions are compared. This result is in marked contrast to previously published observations and has significant implications for the interpretation of environmental hydrogen isotope data. We evaluate these trends in light of metabolic gene content of each strain, growth rate, and potential flux and reservoir-size effects of cellular hydrogen, but find no single variable that can account for the differences between nitrate- and sulfate-respiring bacteria. The emerging picture of bacterial hydrogen isotope fractionation is therefore more complex than the simple correspondence between δ2H and metabolic pathway previously understood from aerobes. Despite the complexity, the large signals and rich variability of observed lipid δ2H suggest much potential as an environmental recorder of metabolism.

Fractionation of Hydrogen Isotopes by Sulfate- and Nitrate-Reducing Bacteria.

Science.gov (United States)

Osburn, Magdalena R; Dawson, Katherine S; Fogel, Marilyn L; Sessions, Alex L

2016-01-01

Hydrogen atoms from water and food are incorporated into biomass during cellular metabolism and biosynthesis, fractionating the isotopes of hydrogen-protium and deuterium-that are recorded in biomolecules. While these fractionations are often relatively constant in plants, large variations in the magnitude of fractionation are observed for many heterotrophic microbes utilizing different central metabolic pathways. The correlation between metabolism and lipid δ(2)H provides a potential basis for reconstructing environmental and ecological parameters, but the calibration dataset has thus far been limited mainly to aerobes. Here we report on the hydrogen isotopic fractionations of lipids produced by nitrate-respiring and sulfate-reducing bacteria. We observe only small differences in fractionation between oxygen- and nitrate-respiring growth conditions, with a typical pattern of variation between substrates that is broadly consistent with previously described trends. In contrast, fractionation by sulfate-reducing bacteria does not vary significantly between different substrates, even when autotrophic and heterotrophic growth conditions are compared. This result is in marked contrast to previously published observations and has significant implications for the interpretation of environmental hydrogen isotope data. We evaluate these trends in light of metabolic gene content of each strain, growth rate, and potential flux and reservoir-size effects of cellular hydrogen, but find no single variable that can account for the differences between nitrate- and sulfate-respiring bacteria. The emerging picture of bacterial hydrogen isotope fractionation is therefore more complex than the simple correspondence between δ(2)H and metabolic pathway previously understood from aerobes. Despite the complexity, the large signals and rich variability of observed lipid δ(2)H suggest much potential as an environmental recorder of metabolism.

Effects of the addition of micro silica on the durability of mortars exposed to the sodium sulfate attack

International Nuclear Information System (INIS)

Nasser, C.; Meriam, M.

2012-01-01

This article presents a detailed experimental study on the sulfate attack of mortars of self compacting concrete, and the effectiveness of employs micro silica and limestone fillers in the minimization of the damage resulting from such an attack. The test solution used to supply the sulfate ions and the cations was the sodium sulfate solution 4.5%. The solution saturated with lime was employed as the reference solution. The main variables investigated in the study were the type of cement and mineral addition. The expansion measured on p rims of mortar of (40x40x160) millimeters was employed to estimate their durability after exposure to the sodium sulfate solution attack during 91 days-Specimens of mortars were visually examined to assess the extent of deterioration due to the sulfate attack. The x-ray diffraction was used to evaluate the microstructural nature of the sulfate attack. The test results proved that the use of micro silica had a beneficial effect on the expansion due to the sodium sulfate attack. While mortars with limestone filler have undergoes degradation even with the use of cement resistant to sulfates. (authors).

Permeabilization and recovery of the stratum corneum in vivo: the synergy of photomechanical waves and sodium lauryl sulfate.

Science.gov (United States)

Lee, S; McAuliffe, D J; Kollias, N; Flotte, T J; Doukas, A G

2001-01-01

Photomechanical waves render the stratum corneum permeable and allow macromolecules to diffuse into the epidermis and dermis. The aim of this study was to investigate the combined action of photomechanical waves and sodium lauryl sulfate, an anionic surfactant, for transdermal delivery. A single photomechanical wave was applied to the skin of rats in the presence of sodium lauryl sulfate. The sodium lauryl sulfate solution was removed and aqueous solutions of rhodamine-B dextran (40 kDa molecular weight) were applied to the skin at time points 2, 30, and 60 minutes post-exposure. The presence of rhodamine-B dextran in the skin was measured by fluorescence emission spectroscopy in vivo and fluorescence microscopy of frozen biopsies. The use of sodium lauryl sulfate delayed the recovery of the stratum corneum barrier and extended the time available for the diffusion of dextran through it. The combination of photomechanical waves and surfactants can enhance transdermal drug delivery. Copyright 2001 Wiley-Liss, Inc.

The reactions of oxygen and hydrogen with liquid sodium

International Nuclear Information System (INIS)

Ullmann, H.

1981-01-01

Results so far available as to the reactions and chemical equilibrium of oxygen and hydrogen with liquid sodium have been analyzed critically. The enthalpy values of the reactions have been discussed and supplemented on the basis of corresponding BORN-HABER cycles. The concentration and temperature functions of the hydrogen equilibrium pressure were deduced from experimental results. In relation to the solubility data the solid phases coexisting with liquid sodium in the ternary system Na-O-H have been discussed. The reaction of oxygen with hydrogen in diluted solution in liquid sodium has been investigated in more detail. Interaction coefficients, and the temperature functions of the free energy of formation and the equilibrium constant have been determined. (orig.)

The determination of hydrogen in sodium by vacuum extraction

International Nuclear Information System (INIS)

Qi Linkun; Wan Gang; Wen Ximeng; Sun Shiping; Jia Yunteng

1993-05-01

A method to determine the hydrogen in sodium is introduced. The sodium sample, which is less than 7 g, is put into a thin iron capsule in argon atmosphere, the capsule is sealed by electron beam welding and heated to 700 degree C in a vacuum system with pressure less than 10 -5 Pa, then the hydrogen released from the vacuum system can be determined. The determining limit by this method is 20 ∼ 150 μg and the standard deviation is 20%. This method uses electron beam welding to replace the argon are welding and combines the off-line sampling with on-line measuring. It is an easier off-line measurement to determine hydrogen in sodium

Effect of sodium sulfite, sodium dodecyl sulfate, and urea on the molecular interactions and properties of whey protein isolate-based films

Science.gov (United States)

Schmid, Markus; Prinz, Tobias K.; Stäbler, Andreas; Sängerlaub, Sven

2016-12-01

Whey protein coatings and cast films are promising for use as food packaging materials. Ongoing research is endeavoring to reduce their permeability. The intention of this study was to evaluate the effect of the reactive additives sodium sulfite, sodium dodecyl sulfate (SDS), and urea on the oxygen barrier, water vapor barrier, and protein solubility of whey protein cast films. The concentration of the reactive additives was 1 to 20 wt.-%. Dried whey protein cast films were used as substrate materials. The water vapor transmission rate, the oxygen permeability, and the protein solubility were measured. Effective diffusion coefficients and effective sorption coefficients were calculated from the results of the water vapor sorption experiments. The presence of sodium sulfite resulted in an increased number of hydrophobic interactions and hydrogen bonds and a slightly decreased number of disulfide bonds. The oxygen permeability decreased from 68 to 46 cm³ (STP / standard temperature and pressure) 100 µm (m² d bar)-1 for 1 wt.-% SDS in the whey protein cast film. The water vapor transmission rate decreased from 165 to 44 g 100 µm (m² d)-1 measured at 50 to 0 % r. h. for 20 wt.-% SDS in the whey protein cast film. The reduction in the water vapor transmission rate correlated with the lower effective diffusion coefficient.

The hydrolysis of C12 primary alkyl sulfates in concentrated aqueous solutions. Part 2. Influence of alkyl structure on hydrolytic reactivity in concentrated aqueous mixtures of sodium primary alkyl sulfates : 1-benzoyl-3-phenyl-1,2,4-triazole as a probe o

NARCIS (Netherlands)

Bethell, Donald; Fessey, Roger E.; Engberts, Jan B.F.N.; Roberts, David W.

2001-01-01

The kinetics of the hydrolysis of aqueous solutions of three sodium C12-alkyl sulfates (SXS), sodium 2-methylundecyl sulfate (SMS), sodium cycloundecylmethyl sulfate (SCS) and sodium 2-pentylheptyl sulfate (SPS), has been investigated at concentrations up to 70% and compared with the behaviour of

Measurements of hydrogen concentration in liquid sodium by using an inert gas carrier method

International Nuclear Information System (INIS)

Funada, T.; Nihei, I.; Yuhara, S.; Nakasuji, T.

1979-01-01

A technique was developed to measure the hydrogen level in liquid sodium using an inert gas carrier method. Hydrogen was extracted into an inert gas from sodium through a thin nickel membrane in the form of a helically wound tube. The amount of hydrogen in the inert gas was analyzed by gas chromatography. The present method is unique in that it can be used over the wide range of sodium temperatures (150 to 700 0 C) and has no problems associated with vacuum systems. The partial pressure of hydrogen in sodium was determined as a function of cold-trap temperature (T/sub c/). Sieverts' constant (K/sub s/) was determined as a function of sodium temperature (T). From Sieverts' constant, the solubility of hydrogen in sodium is calculated. It was found that other impurities in sodium, such as (O) and (OH), have little effect on the hydrogen pressure in the sodium loop

NMR studies of the influence of dodecyl sulfate on the amide hydrogen exchange kinetics of a micelle-solubilized hydrophobic tripeptide

International Nuclear Information System (INIS)

O'Neil, J.D.J.; Sykes, B.D.

1989-01-01

Backbone amide hydrogen exchange measurements are an important source of information about the internal dynamics of proteins. Before such measurements can be interpreted unambiguously, contributions to hydrogen exchange rates from the chemical and physical environment of the amides must be taken into account. Membrane proteins are often solubilized in detergents, yet there have not been any systematic investigations of the possible effects detergents may have on the amide hydrogen exchange rates of proteins. To address this question, the authors have measured individual backbone and carboxyl-terminal amide exchange rates for the amphipathic tripeptide Leu-Val-Ile-amide dissolved in water and dodecyl sulfate micelles. Proton NMR spectroscopy was used to measure exchange using the direct exchange-out into D 2 O technique at 5 degree C and using an indirect steady-state saturation-transfer technique at 25 degree C. The broadening effect of micelle-incorporated spin-labeled fatty acid (12-doxylsterate) on the 1 H NMR spectra of both the detergent and the peptide resonances was used to demonstrate that the tripeptide is intimately associated with the micelle. These experiments help to explain the elevated pH min observed for backbone amides in the sodium dodecyl sulfate solubilized M13 coat protein

Aqueous two-phase (polyethylene glycol + sodium sulfate) system for caffeine extraction: Equilibrium diagrams and partitioning study

International Nuclear Information System (INIS)

Araujo Sampaio, Daniela de; Mafra, Luciana Igarashi; Yamamoto, Carlos Itsuo; Forville de Andrade, Eriel; Oberson de Souza, Michèle; Mafra, Marcos Rogério; Castilhos, Fernanda de

2016-01-01

Highlights: • Binodal curves of PEG (400, 4000 and 6000) + Na_2SO_4 ATPS were determined. • Tie-lines were experimentally determined for aqueous (PEG 400 + Na_2SO_4) system. • Influence of caffeine on LLE of aqueous (PEG 400 + Na_2SO_4) system was investigated. • Partitioning of caffeine in aqueous (PEG 400 + Na_2SO_4) system was investigated. • Caffeine partition showed to be dependent on temperature and TLL. - Abstract: Environmental friendly methods for liquid–liquid extraction have been taken into account due to critical conditions and ecotoxicological effects potentially produced by organic solvents applied in traditional methods. Liquid–liquid extraction using aqueous two phase systems (ATPSs) presents advantages when compared to traditional liquid–liquid extraction. (Polyethylene glycol (PEG) + sodium sulfate + water) ATPS was applied to study partition of caffeine. Binodal curves for ATPSs composed of PEG of different molecular weights (400 g · mol"−"1, 4000 g · mol"−"1 and 6000 g · mol"−"1) sodium sulfate + water were determined by cloud point method at three different temperatures (293.15, 313.15 and 333.15) K. Liquid–liquid equilibrium (LLE) data (tie-lines, slope of the tie-line and tie-lines length) were obtained applying a gravimetric method proposed by Merchuck and co-workers at the same temperatures for aqueous (PEG 400 + sodium sulfate) and aqueous (PEG 400 + sodium sulfate + caffeine) systems. Reliability of the experimental tie-line (TL) data was evaluated using the equations reported by Othmer–Tobias and satisfactory linearity was obtained. Concerning to aqueous (PEG + sodium sulfate) system, the results pointed out that the higher PEG molecular weight the largest is the heterogeneous region. Moreover, temperature showed not to be relevant on binodal curves behavior, but it influenced on tie-line slopes. Partitioning of caffeine in aqueous (PEG 400 + sodium sulfate) system was investigated at different temperatures

Long-term experience with sodium chondroitin sulfate in patients with painful bladder syndrome.

Science.gov (United States)

Tornero, J I; Olarte, H; Escudero, F; Gómez, G

2013-09-01

To assess the response of patients diagnosed with painful bladder syndrome to treatment with instillations of sodium chondroitin sulfate. We present a series of cases of patients with painful bladder syndrome who followed a bladder instillation protocol with sodium chondroitin sulfate, according to our centre's regimen. The response to treatment was assessed with respect to pain, according to the Downie scale; urinary frequency, according to the voiding diary; and subjective improvement, according to the Patient Global Impression of Improvement (PGI-I) scale. A total of 28 patients with a median age of 59 years (range 22-90) followed this protocol. From the medical histories, 19.4% had suffered an infection of the urinary tract, 3.8% had suffered urinary tuberculosis, 7.6% received pelvic radiation therapy and 26.9% had taken anticholinergic drugs for overactive bladder syndrome. We evaluated the response to treatment at 0, 3, 6 and 12 months and found that at the end of treatment 72.3% of the patients had improved bladder pain and 75% were significantly better. Treatment with sodium chondroitin sulfate through endovesical instillation in painful bladder syndrome improves pain, voiding frequency and quality of life in the long term. Copyright © 2013 AEU. Published by Elsevier Espana. All rights reserved.

Sodium sulfate heptahydrate: direct observation of crystallization in a porous material

NARCIS (Netherlands)

Hamilton, A.; Hall, C.; Pel, L.

2008-01-01

It is well known that sodium sulfate causes salt crystallization damage in building materials and rocks. However since the early 1900s the existence of the metastable heptahydrate has been largely forgotten and almost entirely overlooked in scientific publications on salt damage mechanics and on

Pengaruh Penambahan Sodium Lauril Sulfat (Sls) Sebagai Surfaktan Terhadap Sifat Fisik Dan Uji Disolusi Tablet Ketoprofen

OpenAIRE

Pratama, Adithya Wahyu; Siswanto, Agus; Suparman, Suparman

2012-01-01

Ketoprofen (acid 2-(3-benzoilfenil) propanoat) was derivated of propionat acid which has analgesic, antipyretic, and anti-inflammatory with poor solubillity in water. This research allowed to increase the dissolution rate of ketoprofen tablets and effect on the physical characteristic by adding sodium lauril sulfat as surfactant. Sodium lauryl sulfat is a surfactant that can be used to improve wetting and dissolution rate. This study was done with make four formula of ketoprofen tablets by d...

Hydrogen generation systems and methods utilizing sodium silicide and sodium silica gel materials

Energy Technology Data Exchange (ETDEWEB)

Wallace, Andrew P.; Melack, John M.; Lefenfeld, Michael

2017-12-19

Systems, devices, and methods combine thermally stable reactant materials and aqueous solutions to generate hydrogen and a non-toxic liquid by-product. The reactant materials can sodium silicide or sodium silica gel. The hydrogen generation devices are used in fuels cells and other industrial applications. One system combines cooling, pumping, water storage, and other devices to sense and control reactions between reactant materials and aqueous solutions to generate hydrogen. Springs and other pressurization mechanisms pressurize and deliver an aqueous solution to the reaction. A check valve and other pressure regulation mechanisms regulate the pressure of the aqueous solution delivered to the reactant fuel material in the reactor based upon characteristics of the pressurization mechanisms and can regulate the pressure of the delivered aqueous solution as a steady decay associated with the pressurization force. The pressure regulation mechanism can also prevent hydrogen gas from deflecting the pressure regulation mechanism.

Time-resolved fluorescence quenching studies of sodium lauryl ether sulfate micelles

OpenAIRE

Friedrich, Leidi C.; Silva, Volnir O.; Moreira Jr, Paulo F.; Tcacenco, Celize M.; Quina, Frank H.

2013-01-01

Aggregation numbers (N Ag) of micelles of the commercial anionic detergent sodium lauryl ether sulfate (SLES), with an average of two ethylene oxide subunits, were determined at 30 and 40º C by the time-resolved fluorescence quenching method with pyrene as the fluorescent probe and the N-hexadecylpyridinium ion as the quencher. The added-salt dependent growth of SLES micelles (γ = 0.11-0.15, where γ is the slope of a plot of log aggregation number vs. log [Yaq] and [Yaq] is the sodium counter...

Thermodynamics of micelle formation in a water-alcohol solution of sodium tetradecyl sulfate

Science.gov (United States)

Shilova, S. V.; Tret'yakova, A. Ya.; Barabanov, V. P.

2016-01-01

The effects of addition of ethanol and propan-1-ol on sodium tetradecyl sulfate micelle formation in an aqueous solution are studied via microprobe fluorescence microscopy and conductometry. The critical micelle concentration, quantitative characteristics of micelles, and thermodynamic parameters of micelle formation are determined. Addition of 5-15 vol % of ethanol or 5-10 vol % of propan-1-ol is shown to result in a lower critical micelle concentration than in the aqueous solution, and in the formation of mixed spherical micelles whose sizes and aggregation numbers are less than those for the systems without alcohol. The contribution from the enthalpy factor to the free energy of sodium tetradecyl sulfate micelle formation is found to dominate in mixed solvents, in contrast to aqueous solutions.

Glycerin Borax Treatment of Exfoliative Cheilitis Induced by Sodium Lauryl Sulfate: a Case Report.

Science.gov (United States)

Thongprasom, Kobkan

2016-06-01

This paper reports on the results of a case study of a 19-year-old female who presented to the Oral Medicine clinic with a chief complaint of scaly and peeling lips. The lesions had persisted on her lips for more than 7 years and were refractory to previous treatment. Her physician's diagnosis was contact dermatitis. We diagnosed this patient as having exfoliative cheilitis (EC). A patch test using the toothpaste containing sodium lauryl sulfate (SLS) was positive and the patient discontinued using it. Instead, she started using a toothpaste not containing SLS. One year after treating her lesions with hydrogen peroxide mouthwash 1% and glycerin borax, a gradual improvement was observed until returning to normal. Glycerin borax was safe, low cost and simple to use in treatment of refractory exfoliative cheilitis. SLS may have been a precipitating factor in EC in this case.

Glycerin Borax Treatment of Exfoliative Cheilitis Induced by Sodium Lauryl Sulfate: a Case Report

Directory of Open Access Journals (Sweden)

Kobkan Thongprasom

2016-01-01

Full Text Available This paper reports on the results of a case study of a 19-year-old female who presented to the Oral Medicine clinic with a chief complaint of scaly and peeling lips. The lesions had persisted on her lips for more than 7 years and were refractory to previous treatment. Her physician’s diagnosis was contact dermatitis. We diagnosed this patient as having exfoliative cheilitis (EC. A patch test using the toothpaste containing sodium lauryl sulfate (SLS was positive and the patient discontinued using it. Instead, she started using a toothpaste not containing SLS. One year after treating her lesions with hydrogen peroxide mouthwash 1% and glycerin borax, a gradual improvement was observed until returning to normal. Glycerin borax was safe, low cost and simple to use in treatment of refractory exfoliative cheilitis. SLS may have been a precipitating factor in EC in this case.

The equilibrium hydrogen pressure-temperature diagram for the liquid sodium-hydrogen-oxygen system

International Nuclear Information System (INIS)

Knights, C.F.; Whittingham, A.C.

1982-01-01

The underlying equilibria in the sodium-hydrogen-oxygen system are presented in the form of a completmentary hydrogen equilibrium pressure-temperature diagram, constructed by using published data and supplemented by experimental measurements of hydrogen equilibrium pressures over condensed phases in the system. Possible applications of the equilibrium pressure-temperature phase diagram limitations regarding its use are outlined

Response of secondary containment to presence of sodium and hydrogen

International Nuclear Information System (INIS)

Gleikler, E.L.; Huang, T.C.

1979-07-01

As part of an effort to demonstrate that the risk to the public from extremely low probability events in liquid metal fast breeder reactors is bound within an acceptable envelope, containment pressurization by sodium and hydrogen was evaluated. Temperature and pressure histories are presented for typical sodium spray and pool fires and sodium vapor reactions. A review of mechanisms for hydrogen generation and recombination as well as limit for flammability and autocatalytic recombination is provided, and general containment design options to reduce risk are discussed

Reversible effect of dextran sodium sulfate on mucus secreting intestinal epithelial cells

DEFF Research Database (Denmark)

Nielsen, Ditte Søvsø Gundelund; Fredborg, Marlene; Andersen, V

2016-01-01

provide valuable insight into a possible mechanism for dextran sodium sulfate (DSS)–induced colitis of importance for the design of subsequent in vivo studies. To develop a new in vitro IBD model with DSS-induced inflammation in human mucus-secreting intestinal epithelial cells (HT29-MTX-E12), we first...... differentiated in trans-well inserts and DSS solutions were added for 6 d before measuring integrity by transepithelial electrical resistance (TEER) and the permeability to fluorescein isothiocyanate (FITC)–dextran. Then, medium with 10% fetal calf serum (FCS) was added and TEER and FITC-dextran permeability...... were measured after 8 d of treatment. A biphasic response in cell viability was observed with increased viability at low doses and decreased viability at high doses of DSS. Viability was decreased to 29% at the highest dose of DSS (10% vol/wt) for 48 h (P Dextran sodium sulfate significantly...

CLONING AND SEQUENCING OF PSEUDOMONAS GENES DETERMINING SODIUM DODECYL-SULFATE BIODEGRADATION

NARCIS (Netherlands)

DAVISON, J; BRUNEL, F; PHANOPOULOS, A; PROZZI, D; TERPSTRA, P

1992-01-01

The nucleotide sequences of two genes involved in sodium dodecyl sulfate (SDS) degradation, by Pseudomonas, have been determined. One of these, sdsA, codes for an alkyl sulfatase (58 957 Da) and has similarity (31.8% identity over a 201-amino acid stretch) to the N terminus of a predicted protein of

Hydrogen determination in magnesium, zirconium, sodium and lithium using installation, C2532

International Nuclear Information System (INIS)

Malikova, E.D.; Velyukhanov, V.P.; Makhinova, L.O.; Kunin, L.L.

1980-01-01

Techniques of hydrogen determination in magnesium, lithium, sodium and zirconium using the S 2532 installation are developed. The method of oxidizing melting using lead borate has been used for hydrogen determination in lithium and sodium and the method of vacuum extraction - for hydrogen determination in zirconium and magnesium. Zr and Mg extraction has been carried out in steel reactor at the temperatures of 1000 and 650 deg C, the time of extraction being 30 and 10 minutes respectively. A quartz reactor, temperatures of oxidizing melting of 700-800 deg C, the time of analysis 10 and 20 minutes have been used for sodium and lithium. A possibility to determine volumetric content of hydrogen in magnesium at the existing surface contaminations with hydrogen-containing compounds is shown [ru

Weak bases and formation of a less soluble lauryl sulfate salt/complex in sodium lauryl sulfate (SLS) containing media.

Science.gov (United States)

Bhattachar, Shobha N; Risley, Donald S; Werawatganone, Pornpen; Aburub, Aktham

2011-06-30

This work reports on the solubility of two weakly basic model compounds in media containing sodium lauryl sulfate (SLS). Results clearly show that the presence of SLS in the media (e.g. simulated gastric fluid or dissolution media) can result in an underestimation of solubility of some weak bases. We systematically study this phenomenon and provide evidence (chromatography and pXRD) for the first time that the decrease in solubility is likely due to formation of a less soluble salt/complex between the protonated form of the weak base and lauryl sulfate anion. Copyright © 2011 Elsevier B.V. All rights reserved.

Sodium bicarbonate in-duct injection with sodium sulfate recovery for SO2/NOx control

International Nuclear Information System (INIS)

Bennett, R.; Darmstaedter, E.

1991-01-01

Dry sodium injection with sodium bicarbonate has been used commercially at industrial sites since the mid 1980's. In the past three years, five full scale commercial demonstrations have been completed on electric utility coal fired units. Up to 75% SO 2 removal with 0-40% NO x removal has been achieved on units equipped with ESPs. Recent slip stream studies have proven up to 90% SO 2 removal and 25% NO x removal when injection is ahead of a baghouse. If dry sodium bicarbonate sorbent injection technology is used prior to a retrofitted baghouse, but after an existing ESP the sodium sulfate by-product/flyash mixture in the baghouse is over 90% Na 2 SO 4 . Simple filtration and crystallization will yield a high value 99% + pure Na 2 SO 4 for sale. In this application, no liquid discharge occurs and potentially no solids discharge, since flyash recovered from the filter is either recycled to the boiler with the coal stream or reinjected into the boiler. EPA IAPCS model Version 4 is modified to project costs for this SO 2 /NO x removal technology when couples with Na 2 SO 4 recovery. In this paper an example is used to show hardware requirements, consumables accountability, by-product recovery rates, capital costs and levelized costs

Polycation–sodium lauryl ether sulfate-type surfactant complexes : influence of ethylene oxide length

NARCIS (Netherlands)

Vleugels, L.F.W.; Pollet, J.; Tuinier, R.

2015-01-01

Polyelectrolyte-surfactant complexes (PESC) are a class of materials which form spontaneously by self-assembly driven by electrostatic and hydrophobic interactions. PESC containing sodium lauryl ether sulfates (SLES) have found wide application in hair care products like shampoo. Typically, SLES

Polycation-Sodium Lauryl Ether Sulfate-Type Surfactant Complexes : Influence of Ethylene Oxide Length

NARCIS (Netherlands)

Vleugels, Leo F. W.; Pollet, Jennifer; Tuinier, Remco

2015-01-01

Poiyelectrolyte-surfactant complexes (PESC) are a class of materials which form spontaneously by self-assembly driven by electrostatic and hydrophobic interactions. PESC containing sodium lauryl ether Sulfates (SLES) have found wide application in hair care products like shampoo. Typically, SLES

Characterization of Inclusions in Evolution of Sodium Sulfate Using Terahertz Time-domain Spectroscopy.

Science.gov (United States)

Bao, Rima; Wu, Zhikui; Li, Hao; Wang, Fang; Miao, Xinyang; Feng, Chengjing

2017-01-01

The study of fluid inclusion is one of the important means to understanding the evolution of mineral crystals, and can therefore provide original information of mineral evolution. In the process of evolution, outside factors such as temperature and pressure, directly affect the number and size of inclusions, and thus are related to the properties of crystals. In this paper, terahertz time-domain spectroscopy (THz-TDS) was used to detect sodium sulfate crystals with different growth temperatures, and absorption coefficient spectra of the samples were obtained. It is suggested that the evolution of sodium sulfate could be divided into two stages, and 80°C was the turning point. X-ray diffraction (XRD) and polarizing microscopy were used to support this conclusion. The research showed that THz-TDS could characterize the evolution of mineral crystals, and it had a unique advantage in terms of crystal evolution.

Interactions between selected bile salts and Triton X-100 or sodium lauryl ether sulfate

Directory of Open Access Journals (Sweden)

Ćirin Dejan M

2011-12-01

Full Text Available Abstract Background In order to develop colloidal drug carriers with desired properties, it is important to determine physico-chemical characteristics of these systems. Bile salt mixed micelles are extensively studied as novel drug delivery systems. The objective of the present investigation is to develop and characterize mixed micelles of nonionic (Triton X-100 or anionic (sodium lauryl ether sulfate surfactant having oxyethylene groups in the polar head and following bile salts: cholate, deoxycholate and 7-oxodeoxycholate. Results The micellization behaviour of binary anionic-nonionic and anionic-anionic surfactant mixtures was investigated by conductivity and surface tension measurements. The results of the study have been analyzed using Clint's, Rubingh's, and Motomura's theories for mixed binary systems. The negative values of the interaction parameter indicate synergism between micelle building units. It was noticed that Triton X-100 and sodium lauryl ether sulfate generate the weakest synergistic interactions with sodium deoxycholate, while 7-oxodeoxycholate creates the strongest attractive interaction with investigated co-surfactants. Conclusion It was concluded that increased synergistic interactions can be attributed to the larger number of hydrophilic groups at α side of the bile salts. Additionally, 7-oxo group of 7-oxodeoxycholate enhance attractive interactions with selected co-surfactants more than 7-hydroxyl group of sodium cholate.

Interactions between selected bile salts and Triton X-100 or sodium lauryl ether sulfate.

Science.gov (United States)

Cirin, Dejan M; Poša, Mihalj M; Krstonošić, Veljko S

2011-12-29

In order to develop colloidal drug carriers with desired properties, it is important to determine physico-chemical characteristics of these systems. Bile salt mixed micelles are extensively studied as novel drug delivery systems. The objective of the present investigation is to develop and characterize mixed micelles of nonionic (Triton X-100) or anionic (sodium lauryl ether sulfate) surfactant having oxyethylene groups in the polar head and following bile salts: cholate, deoxycholate and 7-oxodeoxycholate. The micellization behaviour of binary anionic-nonionic and anionic-anionic surfactant mixtures was investigated by conductivity and surface tension measurements. The results of the study have been analyzed using Clint's, Rubingh's, and Motomura's theories for mixed binary systems. The negative values of the interaction parameter indicate synergism between micelle building units. It was noticed that Triton X-100 and sodium lauryl ether sulfate generate the weakest synergistic interactions with sodium deoxycholate, while 7-oxodeoxycholate creates the strongest attractive interaction with investigated co-surfactants. It was concluded that increased synergistic interactions can be attributed to the larger number of hydrophilic groups at α side of the bile salts. Additionally, 7-oxo group of 7-oxodeoxycholate enhance attractive interactions with selected co-surfactants more than 7-hydroxyl group of sodium cholate.

Selective hydrogenation of 4-isobutylacetophenone over a sodium-promoted Pd/C catalyst

International Nuclear Information System (INIS)

Cho, Hong-Baek; Lee, Bae Uk; Nakayama, Tadachika; Park, Yeung-Ho; Ryu, Chung-Han

2013-01-01

The effect of sodium promotion on the selective hydrogenation of 4-isobutylacetophenone, 4-IBAP, was investigated over a Pd/C catalyst. A precipitation and deposition method was used to prepare the catalyst, and sodium was promoted on the Pd/C catalyst via post-impregnation while varying the sodium content. The sodium-promoted Pd/C catalyst resulted in a significantly improved yield greater than 96% of the desired product, 1-(4-isobutylphenyl) ethanol (4-IBPE), compared with the non-patented literature results under a mild hydrogenation condition. A detailed hydrogenation network over the Pd/C catalyst was suggested. The reaction mechanism for the yield and selectivity enhancement of 4-IBPE induced-by the promoted Pd/C was elucidated in relation to the geometric and electronic effects of reactant molecules in the microporous support depending on the reaction steps

Comparison between sodium hypochlorite and copper sulfate reducer in lightening of overexposed working length radiographs

Directory of Open Access Journals (Sweden)

Fatemeh Ezoddini Ardakani

2015-12-01

Full Text Available Objectives: The aims of this study were to test whether lightening of the overexposed radiographs improve determination of endodontic files length and whether lightened radiographs are comparable with ideally exposed radiographs. Material and Methods: Four dried human skull coated with soft tissue-equivalent wax used for exposing radiographs of the upper molars. First, the endodontic file was placed in full length of the root and four series of radiographs obtained. The time to expose the first series was unchanged (standard group but increased for the other three series.  Two series of overexposed radiographs set as test groups (one lightened with copper sulfate reducer and the other lightened with sodium hypochlorite and one series set as control group. Then the endodontic file placed 2mm short in the root and four series of radiographs obtained like the former. A viewer evaluated radiographs. ROC curves were obtained and areas under the curves were calculated. Sensitivity, specificity and Cohen’s kappa was calculated. Results: The average area under ROC curves was 1, 0.995,1 and 0.643 for the standard, Copper sulfate, sodium hypochlorite and the control group, respectively. Sodium hypochlorite show a better performance in terms of sensitivity and specificity compared to Copper sulfate. Differences between the test radiographs and standard and control radiographs were significant (p

Density functional theory study on the ionic liquid pyridinium hydrogen sulfate

Science.gov (United States)

Tankov, Ivaylo; Yankova, Rumyana; Genieva, Svetlana; Mitkova, Magdalena; Stratiev, Dicho

2017-07-01

The geometry, electronic structure and chemical reactivity of a pyridinium-based ionic liquid, pyridinium hydrogen sulfate ([H-Pyr]+[HSO4]-), have been discussed on the basis of quantum chemical density functional theory calculations using B3LYP/6-311+G(d,p) and B3LYP/6-311++G(2d,2p) approaches. The calculations indicated that [H-Pyr]+[HSO4]- exists in the form of an ion pair. A large electropositive potential was found on the pyridinium ring, while the regions of a negative electrostatic potential is linked with the lone pair of electronegative oxygen atoms in hydrogen sulfate anion ([HSO4]-). Electron transfer both within the anion, and between the anion and cation of an ion pair were described using natural bond orbital theory. The energy values of -7.1375 and -2.8801 eV were related to HOMO and LUMO orbitals, respectively.

Preparative isolation of a cytotoxic principle of a forest mushroom Suillus luteus by sodium dodecyl sulfate based "salting-in" countercurrent chromatography.

Science.gov (United States)

Yang, Zhi; Hu, Xueqian; Wu, Shihua

2016-02-01

In the course of screening new anticancer natural products, an edible forest mushroom Suillus luteus (L. Ex Franch). Gray was found to have potent cytotoxicity against several human cancer cells. However, the lipophilic sample made some countercurrent chromatography solvent systems emulsify, which caused difficulties in the separation of its cytotoxic components. Here, we found that the addition of an organic salt sodium dodecyl sulfate could efficiently shorten the settling time of the mushroom sample solutions by eliminating the emulsification of two-phase solvent systems. Moreover, we found that sodium dodecyl sulfate could play a new "salting-in" role and made the partition coefficients of the solutes decrease with the increased concentrations. Thus, a sodium dodecyl sulfate based salting-in countercurrent chromatography method has been successfully established for the first time for preparative isolation of a cytotoxic principle of the mushroom. The active component was identified as isosuillin. Whole results indicated that sodium dodecyl sulfate could be used as an efficient salting-in reagent for two-phase solvent system selection and targeted countercurrent chromatography isolation. It is very useful for current natural products isolation and drug discovery. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of Cheap Antidotes; Sodium Bicarbonate and Magnesium Sulfate in Organophosphorous Poisoning

International Nuclear Information System (INIS)

Balali-Mood, M.; Afshari, R.

2007-01-01

Organophosphorous (OP) compounds have been used as pesticides and chemical warfare nerve agents. Despite administration of well known antidotes (atropine and oximes), morbidity and mortality of OP poisoning were still high. Besides, oximes are very expensive and not available in most developing countries. It was thus aimed to study the effects of cheap available antidotes; sodium bicarbonate and magnesium sulfate in OP poisoning. In addition to the standard antidotal treatment, out of 117 patients (63M, 47F) aged 25.2 ± 9.5 years with moderate to severe acute OP pesticide poisoning 59 were given sodium bicarbonate 5 mEq/kg in 60 min. followed by 5-6 mEq/kg/day to obtain arterial blood pH of 7.45 to 7.55. Arterial blood pH increased significantly (p less than 0.01) to 7.48 ± 0.05 compared to the controls (7.32 ± 0.06). Morbidity based on hospitalization days reduced significantly (p less than 0.05) from 5.62 ± 3.4 in the controls to 3.1 ± 2.6 days in the sodium bicarbonate group. Total atropine dose was also significantly (p less than 0.05) lower in the test group. Mortality was lower, but not significantly due to the low numbers (5 and 2 of the controls and test group, respectively). Sodium bicarbonate appeared to be effective and could be added to the treatment regime of OP poisoning. Magnesium sulfate was administered four gram intravenously only for the first 24 hr of hospitalization day for the patients with moderate to severe OP poisoning in a pilot study. The results were promising and thus further investigations are continued.(author)

Dissolution and solubility behavior of fenofibrate in sodium lauryl sulfate solutions.

Science.gov (United States)

Granero, Gladys E; Ramachandran, Chandrasekharan; Amidon, Gordon L

2005-10-01

The solubility of fenofibrate in pH 6.8 McIlvaine buffers containing varying concentrations of sodium lauryl sulfate was determined. The dissolution behavior of fenofibrate was also examined in the same solutions with rotating disk experiments. It was observed that the enhancement in intrinsic dissolution rate was approximately 500-fold and the enhancement in solubility was approximately 2000-fold in a pH 6.8 buffer containing 2% (w/v) sodium lauryl sulfate compared to that in buffer alone. The micellar solubilization equilibrium coefficient (k*) was estimated from the solubility data and found to be 30884+/-213 L/mol. The diffusivity for the free solute, 7.15x10(-6) cm2/s, was calculated using Schroeder's additive molal volume estimates and Hayduk-Laurie correlation. The diffusivity of the drug-loaded micelle, estimated from the experimental solubility and dissolution data and the calculated value for free solute diffusivity, was 0.86x10(-6) cm2/s. Thus, the much lower enhancement in dissolution of fenofibrate compared to its enhancement in solubility in surfactant solutions appears to be consistent with the contribution to the total transport due to enhanced micellar solubilization as well as a large decrease (approximately 8-fold) in the diffusivity of the drug-loaded micelle.

Rhodamine-123: a p-glycoprotein marker complex with sodium lauryl sulfate.

Science.gov (United States)

Al-Mohizea, Abdullah M; Al-Jenoobi, Fahad Ibrahim; Alam, Mohd Aftab

2015-03-01

Aim of this study was to investigate the role of sodium lauryl sulfate (SLS) as P-glycoprotein inhibitor. The everted rat gut sac model was used to study in-vitro mucosal to serosal transport of Rhodamine-123 (Rho-123). Surprisingly, SLS decreases the serosal absorption of Rho-123 at all investigated concentrations. Investigation reveals complex formation between Rhodamine-123 and sodium lauryl sulfate. Interaction profile of SLS & Rho-123 was studied at variable SLS concentrations. The SLS concentration higher than critical micelle concentration (CMC) increases the solubility of Rho-123 but could not help in serosal absorption, on the contrary the absorption of Rho-123 decreased. Rho-123 and SLS form pink color complex at sub-CMC. The SLS concentrations below CMC decrease the solubility of Rho-123. For further studies, Rho-123 & SLS complex was prepared by using solvent evaporation technique and characterized by using differential scanning calorimeter (DSC). Thermal analysis also proved the formation of complex between SLS & Rho-123. The P values were found to be significant (<0.05) except group comprising 0.0001% SLS, and that is because 0.0001% SLS is seems to be very low to affect the solubility or complexation of Rho-123.

Bioaccumulation of sodium alkyl sulfate zinc chloride and their mixture in young goby proterorhinus marmoratus pall

Energy Technology Data Exchange (ETDEWEB)

Topcuoglu, S.; Birol, E. (Cekmece Nuclear Research and Training Center, Istanbul (Turkey))

1982-12-01

The bioaccumulation of labelled surfactant, 35S-labelled sodium lauryl sulfate and 65Zn-labelled zinc chloride, was investigated both as a mixture and alone by themselves in young goby. The concentration factor of 7.15 was calculated for the surfactant in the whole-body fish and there was no effect of zinc chloride on this bioaccumulation process. Biological half-life of the surfactant was around 35 hours. The effects of surfactants on the zinc accumulation were also followed under the same conditions. The results indicated that the sodium lauryl sulfate had no effect on the accumulation of zinc, however, the other surfactant, linear alkylbenzene sulfonate, caused a significant increase in the zinc accumulation in comparison with the control group, during the uptake period.

Bioaccumulation of sodium alkyl sulfate zinc chloride and their mixture in young goby proterorhinus marmoratus pall

International Nuclear Information System (INIS)

Topcuoglu, S.; Birol, E.

1982-01-01

The bioaccumulation of labelled surfactant, 35S-labelled sodium lauryl sulfate and 65Zn-labelled zinc chloride, was investigated both as a mixture and alone by themselves in young goby. The concentration factor of 7.15 was calculated for the surfactant in the whole-body fish and there was no effect of zinc chloride on this bioaccumulation process. Biological half-life of the surfactant was around 35 hours. The effects of surfactants on the zinc accumulation were also followed under the same conditions. The results indicated that the sodium lauryl sulfate had no effect on the accumulation of zinc, however, the other surfactant, linear alkylbenzene sulfonate, caused a significant increase in the zinc accumulation in comparison with the control group, during the uptake period. (author)

Contribution to the study of hydrogenated and oxygenated impurities in liquid sodium

International Nuclear Information System (INIS)

Naud, G.

1964-07-01

This study is made up essentially of two parts. The first is devoted to the development of dosage methods for selectively determining the oxygenated and hydrogenated impurities present in sodium, that is the oxide, the hydride and the hydroxide. The second makes use of these methods for a study of the Na-H 2 -O 2 system, as well as of the related problem of the attack of pyrex glass by molten sodium. The conventional method for dosing oxygen by amalgamation was first adapted to the simultaneous measurement of the hydride. We then developed a method for dosing the total hydrogen by measuring successively the concentrations of gas present in the hydride and hydroxide form. This method is based on the thermal decomposition of the hydride and the reaction between sodium and the hydroxide. Our contribution to the study of the Na-H 2 -O 2 System consists first of all in the study of the reaction between hydrogen and sodium in the temperature range from 150 to 250 deg C and at a pressure of about 150 mm of mercury. The study of the thermal decomposition of the hydride in sodium was then studied. It was possible to make some qualitative observations concerning the reaction between sodium and sodium hydroxide. Finally some complementary tests made it possible to define the nature of the phenomena occurring during the attack of pyrex glass by sodium. (author) [fr

Pathways of sulfate and hydrogen sulfide transformations in a BTEX- contaminated groundwater system

DEFF Research Database (Denmark)

Einsiedl, Florian; Anneser, B.; Griebler, C.

2010-01-01

in complex environmental systems. As a result, compound specific stable isotope signatures in various sulfur species were determined in a tar-oil contaminated site and were linked to the microbial community distribution in the aquifer. The goal of the study was to reach an integrated understanding of sulfur...... intermediate during abiotic oxidation of hydrogen sulphide, with the latter formed during bacterial sulfate reduction. The formed elemental sulfur may be used by the specific microbial community found in this aquifer for the oxidation of organic contaminants such as toluene. In contrast, reoxidation...... of hydrogen sulfide to sulfate by molecular oxygen may affect sulfur cycling within the transition between the unsaturated and the saturated zones and therefore attenuate concentrations of contaminants in groundwater as well....

The monitoring of oxygen, hydrogen and carbon in the sodium circuits of the PFR

International Nuclear Information System (INIS)

Mason, L.; Morrison, N.S.; Robertson, C.M.; Trevillion, E.A.

1984-01-01

The paper reviews the instrumentation available for monitoring oxygen, hydrogen, tritium and carbon impurity levels on the primary and secondary circuits of PFR. Circuit oxygen levels measured using electrochemical oxygen meters are compared to estimates from circuit plugging meters. The data are interpreted in the light of information from cold trap temperatures. Measurements of secondary circuit hydrogen levels using both the sodium and gas phase hydrogen detection equipment are compared to estimates of circuit hydrogen levels from plugging meters and variations in sodium phase hydrogen levels during power operation are discussed. (author)

Sodium Dodecyl Sulfate (SDS)-Loaded Nanoporous Polymer as Anti-Biofilm Surface Coating Material

DEFF Research Database (Denmark)

Li, Li; Molin, Søren; Yang, Liang

2013-01-01

-b-polydimethylsiloxane (1,2-PB-b-PDMS) block copolymer via chemical cross-linking of the 1,2-PB block followed by quantitative removal of the PDMS block. Sodium dodecyl sulfate (SDS) was loaded into the nanoporous 1,2-PB from aqueous solution. The SDS-loaded nanoporous polymer films were shown to block bacterial attachment...

The influence of sodium lauryl sulfate on the crystal phases of titania by hydrothermal method

Science.gov (United States)

Liu, Chaohong; Wang, Xin

2012-11-01

In this paper, we prepared TiO2 nanostructures by a hydrothermal method and investigated the influence of the SO4^{2-} ion and the effect of long alkyl chains of sodium dodecyl sulfate on the crystal phases of TiO2 by experiments and theoretical calculations. The results indicate that the absorption of the H+HSO4 fragment on rutile (110) is more stable than that of the 2H+SO4 fragment and more favorable to the formation of anatase. The absorption and steric effects of sodium dodecyl sulfate on the surfaces of TiO2 grains also have an important influence on the formation of mixed crystals by changing the speed and the way of octahedral TiO6 units combining. Based on the above facts, we revised the original reaction scheme for crystalline titania formation by previous authors.

Polarization measurement of atomic hydrogen beam spin-exchanged with optically oriented sodium atoms

International Nuclear Information System (INIS)

Ueno, Akira; Ogura, Kouichi; Wakuta, Yoshihisa; Kumabe, Isao

1988-01-01

The spin-exchange reaction between hydrogen atoms and optically oriented sodium atoms was used to produce a polarized atomic hydrogen beam. The electron-spin polarization of the atomic hydrogen beam, which underwent the spin-exchange reaction with the optically oriented sodium atoms, was measured. A beam polarization of -(8.0±0.6)% was obtained when the thickness and polarization of the sodium target were (5.78±0.23)x10 13 atoms/cm 2 and -(39.6±1.6)%, respectively. The value of the spin-exchange cross section in the forward scattering direction, whose scattering angle in the laboratory system was less than 1.0 0 , was obtained from the experimental results as Δσ ex =(3.39±0.34)x10 -15 cm 2 . This value is almost seven times larger than the theoretical value calculated from the Na-H potential. The potential was computed quantum mechanically in the space of the appropriate wave functions of the hydrogen and the sodium atoms. (orig./HSI)

Enhanced sulfate reduction with acidogenic sulfate-reducing bacteria

International Nuclear Information System (INIS)

Wang Aijie; Ren Nanqi; Wang Xu; Lee Duujong

2008-01-01

Sulfate reduction in a continuous flow, acidogenic reactor using molasses wastewater as the carbon source was studied at varying chemical oxygen demand/sulfate (COD/SO 4 2- ) ratios. At a critical COD/SO 4 2- ratio of 2.7, neither COD nor sulfate were in excess for extra production of ethanol or acetate in the reactor. An acetic-type microbial metabolism was established with sulfate-reducing bacteria (SRB) significantly consuming hydrogen and volatile fatty acids produced by acidogenic bacteria and hydrogen producing acetogens in degrading COD, thereby yielding sulfate removal rate >94.6%. A low critical COD/SO 4 2- ratio of 1.6 was also observed with the enriched ASRB population in reactor which overcomes the barrier to the treatment capability of sulfate-laden wastewater treatment with limited COD supply

Effects of Sodium Citrate on the Ammonium Sulfate Recycled Leaching of Low-Grade Zinc Oxide Ores

Science.gov (United States)

Yang, Kun; Li, Shi-wei; Zhang, Li-bo; Peng, Jin-hui; Ma, Ai-yuan; Wang, Bao-bao

2016-03-01

The effects of sodium citrate on ammonium sulfate recycled leaching of low-grade zinc oxide ores were studied. By applying various kinds of detection and analysis techniques such as chemical composition analysis, chemical phase method, scanning electron microscopy and energy dispersive spectrum (SEM/EDS), X-ray diffraction (XRD) and Fourier-transforming infrared spectrum (FT-IR), zinc raw ore, its leaching slag and the functional mechanism of sodium citrate were investigated. Based on a comprehensive analysis, it can be concluded that in contrast to hemimorphite (Zn4Si2O7(OH)2 · H2O), amorphous smithsonite (ZnCO3) and zinc silicate (Zn2SiO4) prove to be refractory phases under ammonium sulfate leaching, while sodium citrate has a better chelating action with the refractory phases, resulting in a higher zinc leaching rate. Under conditions of [NH3]/[NH3]T molar ratio being 0.5, [NH3]T being 7.5 mol/L, [Na3C6H5O7] being 0.2 mol/L, S/L ratio being 1:5, temperature being 303 K, holding time being 1 h in each of the two stages, and stirring rate being 300 rpm, the leaching rate of zinc reached 93.4%. In this article, sulfate ammonium recycled technology also reveals its unique advantage in processing low-grade zinc oxide ores accompanied by high silicon and high alkaline gangue.

Effectiveness of intra-articular injections of sodium hyaluronate-chondroitin sulfate in knee osteoarthritis: a multicenter prospective study.

Science.gov (United States)

Rivera, Fabrizio; Bertignone, Luca; Grandi, Giancarlo; Camisassa, Roberto; Comaschi, Guido; Trentini, Diego; Zanone, Marco; Teppex, Giuseppe; Vasario, Gabriele; Fortina, Giorgio

2016-03-01

Intra-articular injection of hyaluronic acid is a well-established therapy for the treatment of knee osteoarthritis. The aim of the study was to assess the effectiveness and safety of the use of Arthrum HCS(®) (40 mg hyaluronic acid and 40 mg chondroitin sulfate in 2 mL). This was an open, multicenter, prospective study. Men or women over 40 years of age with documented knee osteoarthritis and WOMAC subscore A (severity of pain) ≥25 were enrolled. They received three weekly intra-articular injections of sodium hyaluronate 2 % and chondroitin sulfate 2 % in combination. WOMAC subscore A was assessed at 1, 3 and 6 months after the last injection. One hundred and twelve patients were included (women, 66 %). The mean (SD) WOMAC subscore A decreased from 52.1 (15.2) at inclusion to 20.5 (19.7) at month 6 (P chondroitin sulfate in reducing pain (77 %), improving mobility (78 %) and reducing the consumption of analgesics (74 %). Only one adverse effect was reported by one patient (knee tumefaction). These results suggest that intra-articular injections of Arthrum HCS(®) (sodium hyaluronate plus chondroitin sulfate) in patients with knee osteoarthritis are efficient and safe. These results should be confirmed in a randomized controlled study. IV.

Wustite-based photoelectrodes with lithium, hydrogen, sodium, magnesium, manganese, zinc and nickel additives

Science.gov (United States)

Carter, Emily Ann; Toroker, Maytal Caspary

2017-08-15

A photoelectrode, photovoltaic device and photoelectrochemical cell and methods of making are disclosed. The photoelectrode includes an electrode at least partially formed of FeO combined with at least one of lithium, hydrogen, sodium, magnesium, manganese, zinc, and nickel. The electrode may be doped with at least one of lithium, hydrogen, and sodium. The electrode may be alloyed with at least one of magnesium, manganese, zinc, and nickel.

Effect of sodium lauryl sulfate (SLS) on in vitro percutaneous penetration of water, hydrocortisone and nickel

DEFF Research Database (Denmark)

Frankild, S; Andersen, Klaus Ejner; Nielsen, Gunnar

1995-01-01

The dose- and time-related effect of sodium lauryl sulfate (SLS) on in vitro percutaneous penetration was studied using 3 radiolabeled tracer compounds with different physicochemical properties: tritiated water, hydrocortisone and nickel. Human cadaver abdominal skin from caucasian women was used...

Effects of sodium dodecyl sulfate of polyphenoloxidase

International Nuclear Information System (INIS)

Moore, B.M.; Flurkey, W.H.

1989-01-01

The effects of sodium dodecyl sulfate (SDS) on the enzymatic and physical characteristics of purified broad bean polyphenoloxidase (PPO) were examined. A sigmoidal increase in PPO activation was observed with increasing SDS concentrations. Half maximal activation occurred at .9 mM SDS well below the CMC of 3.5 mM. No apparent changes in the Km for catechol, pH optimum, of I 50 for tropolone were observed in the presence vs absence of SDS. Thermal inactivation and binding of 14 C dopa increased in the presence of SDS. Analytical ultracentrifugation and HPLC-SEC indicated that SDS did not change the apparent size of the PPO under nondenaturing conditions. Scanning fluorescence spectroscopy showed an increase in intrinsic trp/tyr fluorescence at approximately the same concentration in which SDS activation began. Further addition of SDS caused a large increase in intrinsic fluorescence. These results suggest the SDS causes an apparent conformational change induced by SDS binding which leads to enzyme activation

Protective Effect of Daikenchuto on Dextran Sulfate Sodium-Induced Colitis in Mice

OpenAIRE

Matsunaga, Takaharu; Hashimoto, Shinichi; Yamamoto, Naoki; Kawasato, Ryo; Shirasawa, Tomohiro; Goto, Atsushi; Fujisawa, Koichi; Takami, Taro; Okamoto, Takeshi; Nishikawa, Jun; Sakaida, Isao

2017-01-01

Aim. To investigate the effect of daikenchuto (TJ-100; DKT) for ulcerative colitis (UC) model mouse and assess its anti-inflammatory mechanisms. Methods. We evaluated the effects of DKT on dextran sulfate sodium- (DSS-) induced experimental colitis. First, we assessed the short-term effects of DKT using two groups: 5% DSS group and 5% DSS with DKT group. Colon length; histological scores; and interleukin- (IL-) 10, IL-1?, and tumor necrosis factor-? mRNA expression profiles were analyzed usin...

A stronger patch test elicitation reaction to the allergen hydroxycitronellal plus the irritant sodium lauryl sulfate

DEFF Research Database (Denmark)

Heydorn, S; Andersen, K E; Johansen, J D

2003-01-01

Household and cleaning products often contain both allergens and irritants. The aim of this double-blinded, randomized, paired study was to determine whether patch testing with an allergen (hydroxycitronellal) combined with an irritant [sodium lauryl sulfate (SLS)] cause a stronger patch test...

DETERMINATION OF SURFACTANT SODIUM LAURYL ETHER SULFATE BY ION PAIRING CHROMATOGRAPHY WITH SUPPRESSED CONDUCTIVITY DETECTION

Science.gov (United States)

A method for the determination of the anionic Steol CS-330 surfactant is described. CS-330 is a complex mixture of oligomers due to the various sizes of fatty alcohols and the number of moles of the ethoxylation. The main component of CS-330 is sodium lauryl ether sulfate (SLES)....

Development of Bi-phase sodium-oxygen-hydrogen chemical equilibrium calculation program (BISHOP) using Gibbs free energy minimization method

International Nuclear Information System (INIS)

Okano, Yasushi

1999-08-01

In order to analyze the reaction heat and compounds due to sodium combustion, the multiphase chemical equilibrium calculation program for chemical reaction among sodium, oxygen and hydrogen is developed in this study. The developed numerical program is named BISHOP; which denotes Bi-Phase, Sodium - Oxygen - Hydrogen, Chemical Equilibrium Calculation Program'. Gibbs free energy minimization method is used because of the special merits that easily add and change chemical species, and generally deal many thermochemical reaction systems in addition to constant temperature and pressure one. Three new methods are developed for solving multi-phase sodium reaction system in this study. One is to construct equation system by simplifying phase, and the other is to expand the Gibbs free energy minimization method into multi-phase system, and the last is to establish the effective searching method for the minimum value. Chemical compounds by the combustion of sodium in the air are calculated using BISHOP. The Calculated temperature and moisture conditions where sodium-oxide and hydroxide are formed qualitatively agree with the experiments. Deformation of sodium hydride is calculated by the program. The estimated result of the relationship between the deformation temperature and pressure closely agree with the well known experimental equation of Roy and Rodgers. It is concluded that BISHOP can be used for evaluated the combustion and deformation behaviors of sodium and its compounds. Hydrogen formation condition of the dump-tank room at the sodium leak event of FBR is quantitatively evaluated by BISHOP. It can be concluded that to keep the temperature of dump-tank room lower is effective method to suppress the formation of hydrogen. In case of choosing the lower inflammability limit of 4.1 mol% as the hydrogen concentration criterion, formation reaction of sodium hydride from sodium and hydrogen is facilitated below the room temperature of 800 K, and concentration of hydrogen

Corrosion Inhibition of Mild Steel in Hydrochloric Acid by Sodium Lauryl Sulfate (SLS)

OpenAIRE

Atul Kumar

2008-01-01

Effect of Sodium Lauryl Sulfate (SLS), a surfactant on corrosion of mild steel in 1 M hydrochloric acid was studied using three techniques namely: weight loss, electrochemical polarization and metallurgical research microscopy. Results obtained reveal that SLS is good inhibitor and shows very good corrosion inhibition efficiency (IE). The IE was found to vary with concentration of inhibitor and temperature. The electrochemical polarization result revealed that SLS is anodic in nature.

Hydrogen generation from hydrolysis of sodium borohydride using Ru(0) nanoclusters as catalyst

International Nuclear Information System (INIS)

Ozkar, S.; Zahmakiran, M.

2005-01-01

Sodium borohydride is stable in aqueous alkaline solution, however, it hydrolyses in water to hydrogen gas in the presence of suitable catalyst. By this way hydrogen can be generated safely for the fuel cells. Generating H 2 catalytically from NaBH 4 solutions has many advantages: NaBH 4 solutions are nonflammable, reaction products are environmentally benign, rate of H 2 generation is easily controlled, the reaction product NaBO 2 can be recycled, H 2 can be generated even at low temperatures. All of the catalysts that has been used in hydrolysis of sodium borohydride are bulk metals and they act as heterogeneous catalysts. The limited surface area of the heterogeneous catalysts causes lower catalytic activity as the activity of catalyst is directly related to its surface area. Thus, the use of metal nanoparticles with large surface area provides potential route to increase the catalytic activity. Here, we report, for the first time, the use of ruthenium(0) nanoclusters as catalyst in the hydrolysis of sodium borohydride liberating hydrogen gas. The ruthenium nanoparticles are generated from the reduction of ruthenium(III) chloride by sodium borohydride in water and stabilized by specific ligand. The ruthenium(0) nanoclusters are found to be highly active catalyst for the hydrolysis of sodium borohydride

Reduction of sulfate by hydrogen in natural systems: A literature review: Salt Repository Project

International Nuclear Information System (INIS)

Mahoney, J.J.; Strachan, D.M.

1988-01-01

The results of this literature search indicate that the reduction of sulfate by hydrogen gas can occur in nature, but that temperature appears to be a key factor in the rate of this reaction. At temperatures below 200/degree/C, the key factor in the rate of reaction appears to be extremely slow. At low pH the rate of reaction is faster than at high pH. The solution composition also influences the reaction rate; the most recent research available (Yanisagawa 1983) suggests that the concentration of sulfide in solution influences the rate of this reaction. The reduction reaction appears to proceed through a thiosulfate intermediate, so the presence and distribution of other sulfur species will influence the reaction rate. If the reaction mechanism proposed by Yanisagawa is correct, then higher concentrations of sulfide will result in faster rates of sulfate reduction. In conclusion, the reduction of sulfate by hydrogen to form significant amounts of sulfide is a function of temperature, sulfate and sulfide concentrations, pH, and solution composition. The rate of this reaction appears to be very slow under the conditions anticipated in this repository, but given the length of time required to maintain the integrity of the containers (300 to 1000 years) and the unusual solution compositions present, a better understanding of the reaction mechanism is needed. 16 refs., 1 tab

Structural analysis of protein complexes with sodium alkyl sulfates by small-angle scattering and polyacrylamide gel electrophoresis.

Science.gov (United States)

Ospinal-Jiménez, Mónica; Pozzo, Danilo C

2011-02-01

Small-angle X-ray (SAXS) and neutron (SANS) scattering is used to probe the structure of protein-surfactant complexes in solution and to correlate this information with their performance in gel electrophoresis. Proteins with sizes between 6.5 to 116 kDa are denatured with sodium alkyl sulfates (SC(x)S) of variable tail lengths. Several combinations of proteins and surfactants are analyzed to measure micelle radii, the distance between micelles, the extension of the complex, the radius of gyration, and the electrophoretic mobility. The structural characterization shows that most protein-surfactant complexes can be accurately described as pearl-necklace structures with spherical micelles. However, protein complexes with short surfactants (SC(8)S) bind with micelles that deviate significantly from spherical shape. Sodium decyl (SC(10)S) and dodecyl (SC(12)S, more commonly abbreviated as SDS) sulfates result in the best protein separations in standard gel electrophoresis. Particularly, SC(10)S shows higher resolutions for complexes of low molecular weight. The systematic characterization of alkyl sulfate surfactants demonstrates that changes in the chain architecture can significantly affect electrophoretic migration so that protein-surfactant structures could be optimized for high resolution protein separations.

Molecular dynamics simulations of the effects of sodium dodecyl sulfate on lipid bilayer

International Nuclear Information System (INIS)

Xu Bin; Lin Wen-Qiang; Wang Xiao-Gang; Zhou Guo-Quan; Chen Jun-Lang; Zeng Song-wei

2017-01-01

Molecular dynamics simulations have been performed on the fully hydrated lipid bilayer with different concentrations of sodium dodecyl sulfate (SDS). SDS can readily penetrate into the membrane. The insertion of SDS causes a decrease in the bilayer area and increases in the bilayer thickness and lipid tail order, when the fraction of SDS is less than 28%. Through calculating the binding energy, we confirm that the presence of SDS strengthens the interactions among the DPPC lipids, while SDS molecules act as intermedia. Both the strong hydrophilic interactions between sulfate and phosphocholine groups and the hydrophobic interactions between SDS and DPPC hydrocarbon chains contribute to the tight packing and ordered alignment of the lipids. These results are in good agreement with the experimental observations and provide atomic level information that complements the experiments. (paper)

Gamma-ray decontamination of sodium lauryl-ethoxy-sulfate (SLES): microbiological and physicochemical aspects

International Nuclear Information System (INIS)

Lorelli, C. H.; Curzio, O. A.; Horak, Celina I.; Fernandez Gianotti, Tomas; Kairiyama, Eulogia

1999-01-01

Sodium Lauryl-Ethoxy-Sulfate (SLES) is used as a tensioactive in several cleaning and cosmetic products. The paper describes the irradiation tests carried out to decontaminate SLES. The results demonstrate that: 1) 60 Co gamma irradiation of SLES reduces the content of Pseudomona aeroginosa and Pseudomona fluorescens to the levels required by commercial specification; 2) The irradiation with doses u p to 200 Gy does not modify the tensioactive properties of the products. (author)

Corrosion Inhibition of Mild Steel in Hydrochloric Acid by Sodium Lauryl Sulfate (SLS

Directory of Open Access Journals (Sweden)

Atul Kumar

2008-01-01

Full Text Available Effect of Sodium Lauryl Sulfate (SLS, a surfactant on corrosion of mild steel in 1 M hydrochloric acid was studied using three techniques namely: weight loss, electrochemical polarization and metallurgical research microscopy. Results obtained reveal that SLS is good inhibitor and shows very good corrosion inhibition efficiency (IE. The IE was found to vary with concentration of inhibitor and temperature. The electrochemical polarization result revealed that SLS is anodic in nature.

Hydrogen and acetate cycling in two sulfate-reducing sediments: Buzzards Bay and Town Cove, Massachusetts

Energy Technology Data Exchange (ETDEWEB)

Novelli, P.C. (SUNY, Stony Brook, NY (USA) Univ. of Colorado, Boulder (USA)); Michelson, A.R.; Scranton, M.I. (SUNY, Stony Brook, NY (USA)); Banta, G.T.; Hobbie, J.E. (Marine Biological Laboratory, Woods, Hole, MA (USA)); Howarth, R.W. (Cornell Univ., Ithaca, NY (USA))

1988-10-01

Molecular hydrogen and acetate are believed to be key intermediates in the anaerobic remineralization of organic carbon. The authors have made measurements of the cycling of both these compounds in two marine sediments: the bioturbated sediments of Buzzards Bay, Mass., and the much more reducing sediments of Town Cove, Orleans, Mass. Hydrogen concentrations are similar in these environments (from less than 5 to 30 nM), and are within the range previously reported for coastal sediments. However, apparent hydrogen production rates differ by a factor of 60 between these two sediments and at both sites show strong correlation with measured rates of sulfate reduction. Acetate concentrations generally increased with depth in both environments; this increase was greater in Buzzards Bay (22.5 to 71.5 {mu}M) than in Town Cove (26 to 44 {mu}M). Acetate oxidation rates calculated from measured concentrations and {sup 14}C-acetate consumption rate constants suggest that the measured acetate was not all available to sulfate-reducing bacteria. Using the measured sulfate reduction rates, they estimate that between 2% and 100% of the measured acetate pool is biologically available, and that the bioavailable pool decreases with depth. A diagenetic model of the total acetate concentration suggests that consumption may be first order with respect to only a fraction of the total pool.

Effects of various polyoxyethylene sorbitan monooils (Tweens) and sodium dodecyl sulfate on reflux synthesis of copper nanoparticles

International Nuclear Information System (INIS)

Zhang Xifeng; Yin Hengbo; Cheng Xiaonong; Hu Huifeng; Yu Qi; Wang Aili

2006-01-01

Size-controlled synthesis of phase pure Cu nanoparticles was carried out by using copper sulfate pentahydrate as a precursor, ascorbic acid as a reductant, Tweens and sodium dodecyl sulfate (SDS) as modifiers in an aqueous solution at 80 deg. C. The as-prepared Cu nanoparticles were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and Fourier transform infrared (FT-IR). The stabilizing effects of SDS and Tweens on the Cu nanoparticles should be through the coordination between Cu nanoparticles and the respective sulfate group and oxygen-containing bond. The synergic effect of the composite SDS and Tweens on Cu nanoparticles was different from those arising from the individuals

Modification of an acetone-sodium dodecyl sulfate disruption method for cellular protein extraction from neuropathogenic Clostridium botulinum

Science.gov (United States)

An acetone-sodium dodecyl sulfate (SDS) disruption method was used for the extraction of cellular proteins from neurotoxigenic Clostridium botulinum. The amount of protein extracted per gram of dry weight and the protein profile as revealed by polyacrylamide gel electrophoresis (PAGE) was comparabl...

Computational study of pristine and titanium-doped sodium alanates for hydrogen storage applications

Science.gov (United States)

Dathar, Gopi Krishna Phani

The emphasis of this research is to study and elucidate the underlying mechanisms of reversible hydrogen storage in pristine and Ti-doped sodium aluminum hydrides using molecular modeling techniques. An early breakthrough in using complex metal hydrides as hydrogen storage materials is from the research on sodium alanates by Bogdanovic et al., in 1997 reporting reversible hydrogen storage is possible at moderate temperatures and pressures in transition metal doped sodium alanates. Anton reported titanium salts as the best catalysts compared to all other transition metal salts from his further research on transition metal doped sodium alanates. However, a few questions remained unanswered regarding the role of Ti in reversible hydrogen storage of sodium alanates with improved thermodynamics and kinetics of hydrogen desorption. The first question is about the position of transition metal dopants in the sodium aluminum hydride lattice. The position is investigated by identifying the possible sites for titanium dopants in NaAlH4 lattice and studying the structure and dynamics of possible compounds resulting from titanium doping in sodium alanates. The second question is the role of titanium dopants in improved thermodynamics of hydrogen desorption in Ti-doped NaAlH4. Though it is accepted in the literature that formation of TiAl alloys (Ti-Al and TiAl3) is favorable, reaction pathways are not clearly established. Furthermore, the source of aluminum for Ti-Al alloy formation is not clearly understood. The third question in this area is the role of titanium dopants in improved kinetics of hydrogen absorption and desorption in Ti-doped sodium alanates. This study is directed towards addressing the three longstanding questions in this area. Thermodynamic and kinetic pathways for hydrogen desorption in pristine NaAlH4 and formation of Ti-Al alloys in Ti-doped NaAlH 4, are elucidated to understand the underlying mechanisms of hydrogen desorption. Density functional theory

Water leak detection in sodium heated steam generators through measurement of hydrogen concentration in sodium

International Nuclear Information System (INIS)

Cambillard, E.; Lacroix, A.; Martin, P.; Viala, J.

1980-07-01

This report includes a description of apparatus for measuring hydrogen concentration in the secondary sodium system of the PHENIX reactor. The calibration method and results obtained since the commissioning of the reactor are also described. Mention is made of improvements to be built into SUPER PHENIX [fr

Periodate Oxidation for Sulfated Glycosaminoglycans, with Special Reference to the Position of Extra Sulfate Groups in Chondroitin Polysulfates, Chondroitin Sulfate D and Chondroitin Sulfate K

OpenAIRE

Seno, Nobuko; Murakami, Keiko; Shibusawa, Haru

1981-01-01

The optimum conditions for periodate oxidation of sulfated disaccharides were investigated to determine the position of extra sulfate groups on the saturated disulfated disaccharides obtained from chondroitin polysulfates, chondroitin sulfates D and K. Under the conditions: 2mM saturated disulfated disaccharide with 20mM sodium periodate at 37°in the dark, the uronic acid residue in the disulfated disaccharide from chondroitin sulfate D was rapidly and completely destroyed, whereas that in th...

Correlation between hydrogen release and degradation of limestone concrete exposed to hot liquid sodium in inert atmosphere

International Nuclear Information System (INIS)

Parida, F.C.; Das, S.K.; Sharma, A.K.; Ramesh, S.S.; Somayajulu, P.A.; Kannan, S.E.

2005-01-01

Full text of publication follows: Concrete is used as a structural material in a Fast Breeder Reactor (FBR) plant for the construction of its foundation, containment, radiation shield and equipment support structures. An accidental leakage of hot sodium on these civil structures can bring about thermo-chemical reactions, with concrete producing hydrogen gas and causing structural degradation. The concrete damage and hydrogen generation take place concurrently due to conduction of heat from sodium into the concrete and migration of steam / moisture in counter current direction towards sodium. In a series of experiments conducted with limestone concrete for two different types of design corresponding to composition and geometry, were exposed to liquid sodium (∼2 kg) at initial temperatures varying from 180 deg. C to 500 deg. C in an inerted test vessel (Capacity = 203 L). Immersion heater was employed to heat the sodium pool on the concrete cavity during the test period in some test runs. On-line continuous measurement of pressure, temperature, hydrogen gas and oxygen gas was carried out. Pre- and post- test nondestructive testing such as colour photography, spatial profiling of ultrasonic pulse velocity and measurement of dimensions were also conducted. Solid samples were collected from sodium debris by manual core drilling machine and from concrete block by hand held electric drilling machine. These samples were subjected to chemical analysis for the determination of free and bound water along with unburnt and burnt sodium. The hydrogen generation parameters such as average and peak release rate as well as release efficiency are derived from measured test variables. These test variables include temperature, pressure and hydrogen concentration in the argon atmosphere contained in the test vessel. The concrete degradation parameters encompass percentage reduction in ultrasonic pulse velocity, depth of physical and chemical dehydration and sodium penetration. These

Balloon occluded retrograde transvenous obliteration of bleeding stomal varices using sodium tetradecyl sulfate foam: A case report

International Nuclear Information System (INIS)

Kim, Ji Chang; Yang, Po Sang; Lee, Yeon Soo; Kim, Hyun Jeong; Park, Gun

2015-01-01

A small varix is an uncommon complication with a high mortality rate occurring secondary to portal hypertension in patients with a stoma. We describe a case of recurrent stomal varix bleeding successfully managed by balloon occluded retrograde transvenous obliteration using sodium tetradecyl sulfate foam.

Balloon occluded retrograde transvenous obliteration of bleeding stomal varices using sodium tetradecyl sulfate foam: A case report

Energy Technology Data Exchange (ETDEWEB)

Kim, Ji Chang; Yang, Po Sang; Lee, Yeon Soo; Kim, Hyun Jeong; Park, Gun [Dept. of Radiology, The Catholic University of Korea College of Medicine, Daejeon St. Mary' s Hospital, Daejeon (Korea, Republic of)

2015-05-15

A small varix is an uncommon complication with a high mortality rate occurring secondary to portal hypertension in patients with a stoma. We describe a case of recurrent stomal varix bleeding successfully managed by balloon occluded retrograde transvenous obliteration using sodium tetradecyl sulfate foam.

Experimental determination of the phase diagram of the system sodium-sodium hydride up to 9000C and hydrogen pressures up to 800 bar

International Nuclear Information System (INIS)

Klostermeier, W.

1978-01-01

In the present work part of the sodium-sodium hydride system phase diagram has been studied at high temperatures (up to 900 0 C) and high hydrogen pressures (up to 1000 bar). The absorption isothermal curves recorded at temperatures between 650 0 C and 900 0 C show an increase in hydride solubility in sodium from 5.5 mol% at 650 0 to 19 mol% at 900 0 C. The melting point of sodium hydride has been measured giving the value 632 0 C with a hydrogen equilibrium pressure of 106 bar. In the mixing gap region the plateau equilibrium pressure, which is independent of composition, and his temperature dependence have been obtained. The enthalpy and entropy of melting are determined. (GSCH) [de

Analysis of Furaneol in tomato using dynamic headspace sampling with sodium sulfate.

Science.gov (United States)

Buttery, R G; Takeoka, G R; Naim, M; Rabinowitch, H; Nam, Y

2001-09-01

High-flow dynamic headspace sampling with excess anhydrous sodium sulfate was found to be an effective method of isolating Furaneol from fresh tomatoes. Quantitative analysis was carried out by gas chromatography using maltol as internal standard. Furaneol was found in the highest concentrations (660-1100 ppb) in the summer crop of home-grown tomatoes and in some of the greenhouse hydroponically grown tomatoes, which are ripened on the plant before being transported to the supermarkets. Furaneol was found in the lowest concentrations (38-180 ppb) in the common ethylene-ripened, field-grown, supermarket tomatoes.

Subchronic (26- and 52-week) toxicity and irritation studies of a novel microbicidal gel formulation containing sodium lauryl sulfate in animal models.

Science.gov (United States)

Piret, Jocelyne; Laforest, Geneviève; Bussières, Martin; Bergeron, Michel G

2008-03-01

The safety of an ethylene oxide/propylene oxide gel formulation containing sodium lauryl sulfate (2%, w/w), that could be a potent candidate as a topical microbicide, has been evaluated. More specifically, the subchronic (26- and 52-week) toxicity of the formulation when applied intravaginally as well as its irritating potential for the rectal, penile, eye, skin and buccal mucosa have been examined in animal models. The results showed that the vaginal administration of the gel formulation containing sodium lauryl sulfate once and twice daily (with doses 12 +/- 2 h apart) for 26 weeks to rats and for 52 weeks to rabbits induced slight to moderate histopathological alterations. When the formulation was applied intrarectally to male and female rabbits once and twice daily (with doses 12 +/- 2 h apart) for 14 days, no macroscopic or microscopic changes were reported. For both vaginal and rectal dosing, no effect was seen on the haematology, coagulation and serum chemistry parameters as well as on the body weight of animals and the relative organ weights. Other sporadic macroscopic and histopathological findings were incidental in origin and of no toxicological significance. The gel formulation containing sodium lauryl sulfate was considered as mildly irritating for the penile mucosa of rabbits, non-irritating for the eye of rabbits, mildly irritating for the skin in a rabbit model and non-irritating for the hamster cheek pouch. It is suggested that the gel formulation containing sodium lauryl sulfate is safe for most tissues that could be exposed to the product under normal use.

Thermal Decomposition of Sodium Hydrogen Carbonate and Textural Features of Its Calcines

Czech Academy of Sciences Publication Activity Database

Hartman, Miloslav; Svoboda, Karel; Pohořelý, Michael; Šyc, Michal

2013-01-01

Roč. 52, č. 31 (2013), s. 10619-10626 ISSN 0888-5885 R&D Projects: GA MŠk(CZ) 7C11009 Grant - others:RFCS(XE) RFCR-CT-2010-00009 Institutional support: RVO:67985858 Keywords : thermal decomposition * sodium hydrogen carbonate * sodium bicarbonate Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.235, year: 2013

Chondroitin sulfate and sodium hialuronate in treatment of the degenerative joint disease in dogs. Clinical and radiological aspects

International Nuclear Information System (INIS)

Melo, E.G.; Rezende, C.M.F.; Gomes, M.G.; Freitas, P.M.; Arias, S.S.A.

2003-01-01

The aim of this study was the evaluation of the effects of chondroitin sulfate and sodium hyaluronate in the knee joint of dogs with experimentally induced degenerative joint disease (DJD). Fifteen mongrel dogs, weighing 18 to 25kg were used. DJD was induced by cranial cruciate ligament (CCL) arthroscopical transection. After three weeks, CCL was repaired by an intrarticular technique, which uses fascia lata. The dogs were then divided into three groups as follows: group I received no other treatment, but the CCL reconstitution, group II received 24mg/animal of chondroitin sulfate/IM every five days, totaling six injections, and group III received 20mg/animal of sodium hyaluronate /IV every five days, totaling three injections. All dogs were examined clinically and radiographically for 90 days after the repairment surgery. The clinical evaluation was performed by assessment of lameness, weight-bearing, limb muscle atrophy and range of motion. The results demonstrated that the group treated with sodium hyaluronate had lower degree of lameness in comparison with other groups. The radiographic evaluation showed marginal osteophytes and subchondral bone sclerosis. These changes were more severe in the group treated with sodium hyaluronate. The better clinical results observed in this group, compared with the others, was probably due to the greater action of the drug in the synovium, decreasing the pain and lameness. Radiographic findings correlated poorly with the clinical signs in the group treated with sodium hyaluronate [pt

Reactions of oxygen and hydrogen with liquid sodium - a critical survey

International Nuclear Information System (INIS)

Ullmann, H.

1982-01-01

The fundamentals of solvation chemistry are presented with appropriate components formulated. Methods of investigation and kinetics of the reactions are described. The hydrogen equilibrium pressure and saturation solubilities are described. The chemical equilibrium between O and H in solution is presented with detailed tabulation of the saturation solutions of oxygen, hydrogen and hydroxide in liquid sodium. Agreements and differences with the literature are presented

Methanol utilizing Desulfotomaculum species utilizes hydrogen in a methanol-fed sulfate-reducing bioreactor.

Science.gov (United States)

Balk, Melike; Weijma, Jan; Goorissen, Heleen P; Ronteltap, Mariska; Hansen, Theo A; Stams, Alfons J M

2007-01-01

A sulfate-reducing bacterium, strain WW1, was isolated from a thermophilic bioreactor operated at 65 degrees C with methanol as sole energy source in the presence of sulfate. Growth of strain WW1 on methanol or acetate was inhibited at a sulfide concentration of 200 mg l(-1), while on H2/CO2, no apparent inhibition occurred up to a concentration of 500 mg l(-1). When strain WW1 was co-cultured under the same conditions with the methanol-utilizing, non-sulfate-reducing bacteria, Thermotoga lettingae and Moorella mulderi, both originating from the same bioreactor, growth and sulfide formation were observed up to 430 mg l(-1). These results indicated that in the co-cultures, a major part of the electron flow was directed from methanol via H2/CO2 to the reduction of sulfate to sulfide. Besides methanol, acetate, and hydrogen, strain WW1 was also able to use formate, malate, fumarate, propionate, succinate, butyrate, ethanol, propanol, butanol, isobutanol, with concomitant reduction of sulfate to sulfide. In the absence of sulfate, strain WW1 grew only on pyruvate and lactate. On the basis of 16S rRNA analysis, strain WW1 was most closely related to Desulfotomaculum thermocisternum and Desulfotomaculum australicum. However, physiological properties of strain WW1 differed in some aspects from those of the two related bacteria.

Hydrogen bonds of sodium alginate/Antarctic krill protein composite material.

Science.gov (United States)

Yang, Lijun; Guo, Jing; Yu, Yue; An, Qingda; Wang, Liyan; Li, Shenglin; Huang, Xuelin; Mu, Siyang; Qi, Shanwei

2016-05-20

Sodium alginate/Antarctic krill protein composite material (SA/AKP) was successfully obtained by blending method. The hydrogen bonds of SA/AKP composite material were analyzed by Fourier transform infrared spectroscopy (FT-IR) and Nuclear magnetic resonance hydrogen spectrum (HNMR). Experiment manifested the existence of intermolecular and intramolecular hydrogen bonds in SA/AKP system; strength of intermolecular hydrogen bond enhanced with the increase of AKP in the composite material and the interaction strength of hydrogen bonding followed the order: OH…Ether O>OH…π>OH…N. The percentage of intermolecular hydrogen bond decreased with increase of pH. At the same time, the effect of hydrogen bonds on properties of the composite material was discussed. The increase of intermolecular hydrogen bonding led to the decrease of crystallinity, increase of apparent viscosity and surface tension, as well as obvious decrease of heat resistance of SA/AKP composite material. SA/AKP fiber SEM images and energy spectrum showed that crystallized salt was separated from the fiber, which possibly led to the fibrillation of the composite fibers. Copyright © 2016 Elsevier Ltd. All rights reserved.

Sodium 4-phenylbutyrate suppresses the development of dextran sulfate sodium-induced colitis in mice.

Science.gov (United States)

Ono, Kazuhiko; Nimura, Satoshi; Nishinakagawa, Takuya; Hideshima, Yuko; Enjyoji, Munechika; Nabeshima, Kazuki; Nakashima, Manabu

2014-03-01

Sodium 4-phenylbutyrate (PBA) exhibits anti-inflammatory effects by suppressing nuclear factor-κB (NF-κB) activation. In the present study, the effects of PBA on a mouse model of dextran sulfate sodium (DSS)-induced colitis were investigated. The therapeutic efficacy of PBA (150 mg/kg body weight) in DSS-induced colitis was assessed based on the disease activity index (DAI), colon length, the production of inflammatory cytokines and histopathological examination. The results showed an increase in the median survival time in the PBA-treated group compared with that of the untreated DSS control group. DAI scores were lower in the PBA-treated group than in the DSS control group during the 12 days of the experiment. Additionally, PBA treatment inhibited shortening of the colon and the production of the inflammatory cytokines tumor necrosis factor-α, interleukin-1β and IL-6, which were measured in the colonic lavage fluids. Histopathological examination of the DSS control group showed diffused clusters of chronic inflammatory cells infiltrating the lamina propria, partial exfoliation of the surface epithelium and decreased numbers of mature goblet cells. By contrast, in the PBA-treated group the histopathological findings were the same as those of the normal healthy controls. These results suggest that PBA strongly prevents DSS-induced colitis by suppressing the mechanisms involved in its pathogenesis.

Non-Classical Transformation of Benzendiazonium Hydrogen Sulfates. Access to 1,3-Dimethylisochromeno[4,3-c]pyrazol-5(1H-one, a Potential Benzodiazepine Receptor Ligand

Directory of Open Access Journals (Sweden)

Giuseppe Daidone

2013-10-01

Full Text Available The compound 2-((1,3-dimethyl-1H-pyrazol-5-yl(methylcarbamoylbenzene-diazonium hydrogen sulfate (10 was reacted with copper sulfate and sodium chloride, in the presence of ascorbic acid as reducing agent, to afford a mixture of the chlorinated epimers 4′-chloro-2,2′,5′-trimethyl-2′,4′-dihydrospiro[isoindoline-1,3′-pyrazol]-3-one (18 and (19, the epimers 4′-hydroxy-2,2′,5′-trimethyl-2′,4′-dihydrospiro[isoindoline-1,3′-pyrazol]-3-one (20 and (21, and N-(1,3-dimethyl-1H-pyrazol-5-ylbenzamide (22. Under the foregoing conditions, diazonium salt 10 affords neither the 2-chloro-N-(1,3-dimethyl-1H-pyrazol-5-yl-N-methylbenzamide (23 nor the tricyclic derivative 24, the classical products of the Sandmeyer and Pschorr reactions, respectively. Finally, by heating 20 at 210 °C the compound 1,3-dimethylisochromeno[4,3-c]pyrazol-5(1H-one (24 was obtained. The transformation under the above conditions of 2-((4-chloro-3-methyl-1-phenyl- 1H-pyrazol-5-yl(methylcarbamoylbenzendiazonium hydrogen sulphate (11 afforded 4′,4′-dichloro-2,5′-dimethyl-2′-phenyl-2′,4′-dihydrospiro[isoindoline-1,3′-pyrazol]-3-one (29 as the sole reaction product.

Interactions between selected bile salts and Triton X-100 or sodium lauryl ether sulfate

OpenAIRE

Ćirin Dejan M; Poša Mihalj M; Krstonošić Veljko S

2011-01-01

Abstract Background In order to develop colloidal drug carriers with desired properties, it is important to determine physico-chemical characteristics of these systems. Bile salt mixed micelles are extensively studied as novel drug delivery systems. The objective of the present investigation is to develop and characterize mixed micelles of nonionic (Triton X-100) or anionic (sodium lauryl ether sulfate) surfactant having oxyethylene groups in the polar head and following bile salts: cholate, ...

Studies of the effect of ethanol and sodium chloride on the micellization of sodium dodecyl sulfate by gel filtration

Energy Technology Data Exchange (ETDEWEB)

Suzuki, H.

1976-06-01

The effects of the addition of ethanol and sodium chloride to aqueous solutions of sodium dodecyl sulfate (SDS) were studied by the gel-filtration method. With an increase in the concentration of ethanol, the CMC decreased and then increased after passing a minimum, while the micellar weight increased and then decreased, showing a corresponding maximum. Above about 40 vol percent ethanol, no micelle formation was observed. The micellar weight and aggregation number in the presence of ethanol were measured in the SDS concentration range of a constant elution rate of micelles. A decrease in the CMC and an increase in the micellar weight of SDS were observed with an increase in the concentration of NaCl from 0 to 10 mmol/l. The gel-filtration study enabled us to make a direct experimental confirmation of the effects of ethanol and NaCl on the micelle formation of SDS.

Protective effect of isoquercitrin against acute dextran sulfate sodium-induced rat colitis depends on the severity of tissue damage

Czech Academy of Sciences Publication Activity Database

Cibiček, N.; Roubalová, L.; Vrba, J.; Zatloukalová, M.; Ehrmann, J.; Zapletalová, J.; Večeřa, R.; Křen, Vladimír; Ulrichová, J.

2016-01-01

Roč. 68, č. 6 (2016), s. 1197-1204 ISSN 1734-1140 Institutional support: RVO:61388971 Keywords : Isoquercitrin * Quercetin-3-O-beta-D-glucopyranoside * Dextran sulfate sodium Subject RIV: CE - Biochemistry Impact factor: 2.587, year: 2016

Effects of addition of sodium lauryl sulfate on frozen-thawed canine spermatozoa.

Science.gov (United States)

Hori, Tatsuya; Kaseki, Hanae; Fukuhara, Youko; Oba, Hiromichi; Mizutani, Tatsuji; Kawakami, Eiichi; Tsutsui, Toshihiko

2006-10-01

The addition of Orvus ES paste (OEP) to extender may be essential for preparing frozen dog semen. The major ingredient of OEP is sodium lauryl sulfate (SLS). In this study, we compared the effect of SLS on frozen dog semen with that of OEP. There were no significant differences between the 2-mg/ml SLS group and OEP group concerning sperm motility, viability and the percentage of viable sperm with intact acrosomes after freeze-thawing. These results suggest that the effectiveness of frozen dog semen extender containing 2 mg/ml of SLS is similar effective to that demonstrated for OEP.

Combined effects of irritants and allergens. Synergistic effects of nickel and sodium lauryl sulfate in nickel- sensitized individuals

DEFF Research Database (Denmark)

Agner, Tove; Johansen, Jeanne Duus; Overgaard, Lene

2002-01-01

(nickel chloride) and sodium lauryl sulfate (SLS) alone and in combination. Evaluation of skin reactions was performed by colorimetry, measurement of transepidermal water loss and clinical evaluation, and the data were analyzed by logistic dose-response models. A synergistic effect was found of combined...

Skin reaction and regeneration after single sodium lauryl sulfate exposure stratified by filaggrin genotype and atopic dermatitis phenotype

DEFF Research Database (Denmark)

Bandier, J; Carlsen, B C; Rasmussen, M A

2015-01-01

and AD phenotype on irritant response and skin regeneration. OBJECTIVES: To investigate the role of FLGnull and AD groups for skin reaction and recovery after sodium lauryl sulfate (SLS) irritation. METHODS: This is a case-control study comprising 67 subjects, including healthy controls and patients...

System design study of a membrane reforming hydrogen production plant using a small sized sodium cooled reactor

International Nuclear Information System (INIS)

Chikazawa, Y.; Konomura, M.; Hori, T.; Sato, H.; Uchida, S.

2004-01-01

In this study, a membrane reforming hydrogen production plant using a small sized sodium cooled reactor was designed as one of promising concepts. In the membrane reformer, methane and steam are reformed into carbon dioxide and hydrogen with sodium heat at a temperature 500 deg-C. In the equilibrium condition, steam reforming proceeds with catalyst at a temperature more than 800 deg-C. Using membrane reformers, the steam reforming temperature can be decreased from 800 to 500 deg-C because the hydrogen separation membrane removes hydrogen selectively from catalyst area and the partial pressure of hydrogen is kept much lower than equilibrium condition. In this study, a hydrogen and electric co-production plant has been designed. The reactor thermal output is 375 MW and 25% of the thermal output is used for hydrogen production (70000 Nm 3 /h). The hydrogen production cost is estimated to 21 yen/Nm 3 but it is still higher than the economical goal (17 yen/Nm 3 ). The major reason of the high cost comes from the large size of hydrogen separation reformers because of the limit of hydrogen separation efficiency of palladium membrane. A new highly efficient hydrogen separation membrane is needed to reduce the cost of hydrogen production using membrane reformers. There is possibility of multi-tube failure in the membrane reformers. In future study, a design of measures against tube failure and elemental experiments of reaction between sodium and reforming gas will be needed. (authors)

Contribution to the study of hydrogenated and oxygenated impurities in liquid sodium; Contribution a l'etude des impuretees hydrogenees et oxygenees dans le sodium liquide

Energy Technology Data Exchange (ETDEWEB)

Naud, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1964-07-15

This study is made up essentially of two parts. The first is devoted to the development of dosage methods for selectively determining the oxygenated and hydrogenated impurities present in sodium, that is the oxide, the hydride and the hydroxide. The second makes use of these methods for a study of the Na-H{sub 2}-O{sub 2} system, as well as of the related problem of the attack of pyrex glass by molten sodium. The conventional method for dosing oxygen by amalgamation was first adapted to the simultaneous measurement of the hydride. We then developed a method for dosing the total hydrogen by measuring successively the concentrations of gas present in the hydride and hydroxide form. This method is based on the thermal decomposition of the hydride and the reaction between sodium and the hydroxide. Our contribution to the study of the Na-H{sub 2}-O{sub 2} System consists first of all in the study of the reaction between hydrogen and sodium in the temperature range from 150 to 250 deg C and at a pressure of about 150 mm of mercury. The study of the thermal decomposition of the hydride in sodium was then studied. It was possible to make some qualitative observations concerning the reaction between sodium and sodium hydroxide. Finally some complementary tests made it possible to define the nature of the phenomena occurring during the attack of pyrex glass by sodium. (author) [French] Cette etude comporte essentiellement deux parties. La premiere est consacree a la mise au point de methodes de dosages permettant de determiner selectivement les impuretes oxygenees et hydrogenees presentes dans le sodium, a savoir l'oxyde, l'hydrure et l'hydroxyde. La seconde met a profit ces methodes en vue de l'etude du systeme Na-H{sub 2}-O{sub 2}. ainsi que du phenomene connexe d'attaque du verre pyrex par le sodium fondu. La methode classique de dosage de l'oxygene par amalgamation a d'abord ete adaptee au dosage simultane de l'hydrure. Nous avons ensuite mis au point le dosage de l'hydrogene

Ferrous Iron Oxidation by Thiobacillus ferrooxidans: Inhibition with Benzoic Acid, Sorbic Acid, and Sodium Lauryl Sulfate

OpenAIRE

Onysko, Steven J.; Kleinmann, Robert L. P.; Erickson, Patricia M.

1984-01-01

Benzoic acid, sorbic acid, and sodium lauryl sulfate at low concentrations (5 to 10 mg/liter) each effectively inhibited bacterial oxidation of ferrous iron in batch cultures of Thiobacillus ferrooxidans. The rate of chemical oxidation of ferrous iron in low-pH, sterile batch reactors was not substantially affected at the tested concentrations (5 to 50 mg/liter) of any of the compounds.

Disposition, accumulation and toxicity of iron fed as iron (II) sulfate or as sodium iron EDTA in rats

NARCIS (Netherlands)

Appel, M.J.; Kuper, C.F.; Woutersen, R.A.

2001-01-01

A study was performed to provide data on the disposition, accumulation and toxicity of sodium iron EDTA in comparison with iron (II) sulfate in rats on administration via the diet for 31 and 61 days. Clinical signs, body weights, food consumption, food conversion efficiency, hematology, clinical

Studying inhibition of calcium oxalate stone formation: an in vitro approach for screening hydrogen sulfide and its metabolites

Directory of Open Access Journals (Sweden)

S. Vaitheeswari

2015-06-01

Full Text Available ABSTRACTPurpose:Calcium oxalate urolithiasis is one of the most common urinary tract diseases and is of high prevalence. The present study proposes to evaluate the antilithiatic property of hydrogen sulfide and its metabolites like thiosulfate & sulfate in an in vitro model.Materials and Methods:The antilithiatic activity of sodium hydrogen sulfide (NaSH, sodium thiosulfate (Na2S2O3 and sodium sulfate (Na2SO4 on the kinetics of calcium oxalate crystal formation was investigated both in physiological buffer and in urine from normal and recurrent stone forming volunteers. The stones were characterized by optical and spectroscopic techniques.Results:The stones were characterized to be monoclinic, prismatic and bipyramidal habit which is of calcium monohydrate and dihydrate nature. The FTIR displayed fingerprint corresponding to calcium oxalate in the control while in NaSH treated, S=O vibrations were visible in the spectrum. The order of percentage inhibition was NaSH>Na2S2O3>Na2SO4.Conclusion:Our study indicates that sodium hydrogen sulfide and its metabolite thiosulfate are inhibitors of calcium oxalate stone agglomeration which makes them unstable both in physiological buffer and in urine. This effect is attributed to pH changes and complexing of calcium by S2O32-and SO42- moiety produced by the test compounds.

Bioaccumulation profiles of 35S-labelled sodium alkylpoly(oxyethylene) sulfates in carp (Cyprinus carpio)

International Nuclear Information System (INIS)

Kikuchi, M.; Wakabayashi, M.; Kojima, H.; Yoshida, T.

1980-01-01

The uptake, distribution and elimination of two labelled surfactants, 35 S-labelled sodium dodecyltri(oxyethylene) sulfate ( 35 S-C12-AES(3)) and 35 S-labelled sodium dodecylpenta(oxyethylene) sulfate ( 35 S-C12-AES(5)) were investigated in carp (Cyprinus carpio) exposed to concentrations of 0.3-0.6 mg l -1 , using whole-body autoradiography and the liquid scintillation counting method. 35 S-Radioactivity was first rapidly absorbed by the gills and skin and transferred to other organs and tissues. After 24h-exposure, there was a comparatively high accumulation of 35 S-radioactivity in the gills, hepatopancreas, gall bladder, intestinal content, and nasal and oral cavity. The distribution patterns of 35 S-radioactivity derived from 35 S-C12-AES(3) and 35 S-C12-AES(5) in tissues and organs were similar. The whole-body concentration factors of 35 S-radioactivity in fish exposed to 35 SC12-AES(3) and 35 S-C12-AES(5) for 72 hr were 18 and 4.7, respectively. In surfactant-free water, the absorbed 35 S-radioactivity was eliminated more rapidly from the fish body exposed to 35 S-C12-AES(3) than 35 S-C12-AES(5). It was eliminated relatively fast from gills and hepatopancreas, but elimination from gall bladder was rather slow. (author)

Surface modification of graphene oxide nanosheets by protamine sulfate/sodium alginate for anti-cancer drug delivery application

Science.gov (United States)

Xie, Meng; Zhang, Feng; Liu, Lijiao; Zhang, Yanan; Li, Yeping; Li, Huaming; Xie, Jimin

2018-05-01

In order to improve the efficiency of anticancer drug delivery, a graphene oxide (GO) based drug delivery system modificated by natural peptide protamine sulfate (PRM) and sodium alginate (SA) was established via electrostatic attraction at each step of adsorption based on layer-by-layer self-assembly. The nanocomposites were then loaded with anticancer drug doxorubicin hydrochloride (DOX) to estimate the feasibility as drug carriers. The nanocomposites loaded with DOX revealed a remarkable pH-sensitive drug release property. The modification with protamine sulfate and sodium alginate could not only impart the nanocomposites an improved dispersibility and stability under physiological pH, but also suppress the protein adhesion. Due to the high water dispersibility and the small particle size, GO-PRM/SA nanocomposites were able to be uptaken by MCF-7 cells. It was found that GO-PRM/SA nanocomposites exhibited no obvious cytotoxicity towards MCF-7 cells, while GO-PRM/SA-DOX exhibited better cytotoxicity than GO-DOX. Therefore, the GO-PRM/SA nanocomposites were feasible as drug delivery vehicles.

Beyond the detergent effect: a binding site for sodium dodecyl sulfate (SDS) in mammalian apoferritin

Energy Technology Data Exchange (ETDEWEB)

Liu, Renyu, E-mail: renyu.liu@uphs.upenn.edu; Bu, Weiming; Xi, Jin [University of Pennsylvania, Philadelphia, Pennsylvania (United States); Mortazavi, Shirin R. [Drexel University College of Medicine, Philadelphia, Pennsylvania (United States); Cheung-Lau, Jasmina C.; Dmochowski, Ivan J. [University of Pennsylvania, Philadelphia, Pennsylvania (United States); Loll, Patrick J., E-mail: renyu.liu@uphs.upenn.edu [Drexel University College of Medicine, Philadelphia, Pennsylvania (United States); University of Pennsylvania, Philadelphia, Pennsylvania (United States)

2012-05-01

Using X-ray crystallography and isothermal titration calorimetry, we show that sodium dodecyl sulfate (SDS) binds specifically to a pre-formed internal cavity in horse-spleen apoferritin. Although sodium dodecyl sulfate (SDS) is widely used as an anionic detergent, it can also exert specific pharmacological effects that are independent of the surfactant properties of the molecule. However, structural details of how proteins recognize SDS are scarce. Here, it is demonstrated that SDS binds specifically to a naturally occurring four-helix bundle protein: horse apoferritin. The X-ray crystal structure of the apoferritin–SDS complex was determined at a resolution of 1.9 Å and revealed that the SDS binds in an internal cavity that has previously been shown to recognize various general anesthetics. A dissociation constant of 24 ± 9 µM at 293 K was determined by isothermal titration calorimetry. SDS binds in this cavity by bending its alkyl tail into a horseshoe shape; the charged SDS head group lies in the opening of the cavity at the protein surface. This crystal structure provides insights into the protein–SDS interactions that give rise to binding and may prove useful in the design of novel SDS-like ligands for some proteins.

Volcano Plot for Bimetallic Catalysts in Hydrogen Generation by Hydrolysis of Sodium Borohydride

Science.gov (United States)

Koska, Anais; Toshikj, Nikola; Hoett, Sandra; Bernaud, Laurent; Demirci, Umit B.

2017-01-01

In the field of "hydrogen energy", sodium borohydride (NaBH[subscript 4]) is a potential hydrogen carrier able to release H[subscript 2] by hydrolysis in the presence of a metal catalyst. Our laboratory experiment focuses on this. It is intended for thirdyear undergraduate students in order to have hands-on laboratory experience through…

75 FR 56101 - Lauryl Sulfate Salts Registration Review Final Decision; Notice of Availability

Science.gov (United States)

2010-09-15

... decision for the pesticide, lauryl sulfate salts (also known as sodium lauryl salts), case 4061... announces the availability of EPA's final registration review decision for the lauryl sulfate salts. Sodium... product that contains sodium lauryl sulfate as an active ingredient. The product, Kleenex[reg] Brand...

Ferrous Iron Oxidation by Thiobacillus ferrooxidans: Inhibition with Benzoic Acid, Sorbic Acid, and Sodium Lauryl Sulfate

Science.gov (United States)

Onysko, Steven J.; Kleinmann, Robert L. P.; Erickson, Patricia M.

1984-01-01

Benzoic acid, sorbic acid, and sodium lauryl sulfate at low concentrations (5 to 10 mg/liter) each effectively inhibited bacterial oxidation of ferrous iron in batch cultures of Thiobacillus ferrooxidans. The rate of chemical oxidation of ferrous iron in low-pH, sterile batch reactors was not substantially affected at the tested concentrations (5 to 50 mg/liter) of any of the compounds. PMID:16346592

Removal of hydrogen sulfide as ammonium sulfate from hydropyrolysis product vapors

Energy Technology Data Exchange (ETDEWEB)

Marker, Terry L.; Felix, Larry G.; Linck, Martin B.; Roberts, Michael J.

2017-03-14

A system and method for processing biomass into hydrocarbon fuels that includes processing a biomass in a hydropyrolysis reactor resulting in hydrocarbon fuels and a process vapor stream and cooling the process vapor stream to a condensation temperature resulting in an aqueous stream. The aqueous stream is sent to a catalytic reactor where it is oxidized to obtain a product stream containing ammonia and ammonium sulfate. A resulting cooled product vapor stream includes non-condensable process vapors comprising H.sub.2, CH.sub.4, CO, CO.sub.2, ammonia and hydrogen sulfide.

Removal of hydrogen sulfide as ammonium sulfate from hydropyrolysis product vapors

Science.gov (United States)

Marker, Terry L; Felix, Larry G; Linck, Martin B; Roberts, Michael J

2014-10-14

A system and method for processing biomass into hydrocarbon fuels that includes processing a biomass in a hydropyrolysis reactor resulting in hydrocarbon fuels and a process vapor stream and cooling the process vapor stream to a condensation temperature resulting in an aqueous stream. The aqueous stream is sent to a catalytic reactor where it is oxidized to obtain a product stream containing ammonia and ammonium sulfate. A resulting cooled product vapor stream includes non-condensable process vapors comprising H.sub.2, CH.sub.4, CO, CO.sub.2, ammonia and hydrogen sulfide.

The distribution of n-caprylic acid between organic solvents and aqueous sodium sulfate solution

International Nuclear Information System (INIS)

Gloe, K.; Muehl, P.; Kholkin, A.I.; Gindin, L.M.

1981-01-01

The distribution of 14 C-labelled n-caprylic acid between n-decane, benzene, isoamyl acetate, diisopropyl ketone, isoamyl alcohol and an aqueous 0.6 molar sodium sulfate solution was studied. The distribution constants and the dimerisation constants were determined for the reactions HRsub((w)) reversible HRsub((org)) and 2 HRsub((org)) reversible (HR)sub(2(org)), respectively. Both the effect of the solvent on the acid distribution and the importance of such studies for the interpretation of liquid-liquid extraction equilibria are discussed. (author)

One-step microwave synthesis of photoluminescent carbon nanoparticles from sodium dextran sulfate water solution

Science.gov (United States)

Kokorina, Alina A.; Goryacheva, Irina Y.; Sapelkin, Andrei V.; Sukhorukov, Gleb B.

2018-04-01

Photoluminescent (PL) carbon nanoparticles (CNPs) have been synthesized by one-step microwave irradiation from water solution of sodium dextran sulfate (DSS) as the sole carbon source. Microwave (MW) method is very simple and cheap and it provides fast synthesis of CNPs. We have varied synthesis time for obtaining high luminescent CNPs. The synthesized CNPs exhibit excitation-dependent photoluminescent. Final CNPs water solution has a blue- green luminescence. CNPs have low cytotoxicity, good photostability and can be potentially suitable candidates for bioimaging, analysis or analytical tests.

Continuous analyzers of hydrogen and carbon in liquid sodium and of hydrocarbon total in protective atmosphere above sodium

International Nuclear Information System (INIS)

Pitak, O.; Fresl, M.

1980-01-01

The principle is described of a leak detector for detecting water penetration into sodium in a steam generator. The device operates as a diffusion H-meter with an ion pump. Ni or Fe diffusion diaphragm is washed with sodium while diffused hydrogen is pumped and also monitored with the ion pump. Another detector uses the principle of analyzing hydrocarbons in the cover gas above the sodium level. The carrier gas flow for the analyzer divided into measuring and reference parts is passed through a chamber housing the diffusion standard. For measuring carbon content in sodium, the detector analytical part may be completed with a chamber with moisturizing filling for scrubbing gas. Carbon passing through the diffusion Fe diaphragm is scrubbed on the inner wall in the form of CO which is reduced to methane and measured using the detector C-meter. (M.S.)

Metabolic interactions in methanogenic and sulfate-reducing bioreactors.

Science.gov (United States)

Stams, A J M; Plugge, C M; de Bok, F A M; van Houten, B H G W; Lens, P; Dijkman, H; Weijma, J

2005-01-01

In environments where the amount of electron acceptors is insufficient for complete breakdown of organic matter, methane is formed as the major reduced end product. In such methanogenic environments organic acids are degraded by syntrophic consortia of acetogenic bacteria and methanogenic archaea. Hydrogen consumption by methanogens is essential for acetogenic bacteria to convert organic acids to acetate and hydrogen. Several syntrophic cocultures growing on propionate and butyrate have been described. These syntrophic fatty acid-degrading consortia are affected by the presence of sulfate. When sulfate is present sulfate-reducing bacteria compete with methanogenic archaea for hydrogen and acetate, and with acetogenic bacteria for propionate and butyrate. Sulfate-reducing bacteria easily outcompete methanogens for hydrogen, but the presence of acetate as carbon source may influence the outcome of the competition. By contrast, acetoclastic methanogens can compete reasonably well with acetate-degrading sulfate reducers. Sulfate-reducing bacteria grow much faster on propionate and butyrate than syntrophic consortia.

Role of sodium hydroxide in the production of hydrogen gas from the hydrothermal gasification of biomass

Energy Technology Data Exchange (ETDEWEB)

Onwudili, Jude A.; Williams, Paul T. [Energy and Resources Research Institute, University of Leeds, Leeds, LS2 9JT (United Kingdom)

2009-07-15

The role of sodium hydroxide as a promoter of hydrogen gas production during the hydrothermal gasification of glucose and other biomass samples has been investigated. Experiments were carried out in a batch reactor with glucose and also in the presence of the alkali from 200 C, 2 MPa to 450 C, 34 MPa at constant water loading. Without sodium hydroxide, glucose decomposed to produce mainly carbon dioxide, water, char and tar. Furfural, its derivatives and reaction products dominated the ethyl acetate extract of the water (organic fraction) at lower reaction conditions. This indicated that the dehydration of glucose to yield these products was unfavourable to hydrogen gas production. In the presence of sodium hydroxide however, glucose initially decomposed to form mostly alkylated and hydroxylated carbonyl compounds, whose further decomposition yielded hydrogen gas. It was observed that at 350 C, 21.5 MPa, half of the optimum hydrogen gas yield had formed and at 450 C, 34 MPa, more than 80 volume percent of the gaseous effluent was hydrogen gas, while the balance was hydrocarbon gases, mostly methane ({>=}10 volume percent). Other biomass samples were also comparably reacted at the optimum conditions observed for glucose. The rate of hydrogen production for the biomass samples was in the following order; glucose > cellulose, starch, rice straw > potato > rice husk. (author)

Sensitive detection of oversulfated chondroitin sulfate in heparin sodium or crude heparin with a colorimetric microplate based assay.

Science.gov (United States)

Sommers, Cynthia D; Mans, Daniel J; Mecker, Laura C; Keire, David A

2011-05-01

In this work we describe a 96-well microplate assay for oversulfated chondroitin sulfate A (OSCS) in heparin, based on a water-soluble cationic polythiophene polymer (3-(2-(N-(N'-methylimidazole))ethoxy)-4-methylthiophene (LPTP)) and heparinase digestion of heparin. The assay takes advantage of several unique properties of heparin, OSCS, and LPTP, including OSCS inhibition of heparinase I and II activity, the molecular weight dependence of heparin-LPTP spectral shifts, and the distinct association of heparin fragments and OSCS to LPTP. These factors combine to enable detection of the presence of 0.003% w/w spiked OSCS in 10 μg of heparin sodium active pharmaceutical ingredient (API) using a plate reader and with visual detection to 0.1% levels. The same detection limit for OSCS was observed in the presence of 10% levels of dermatan sulfate (DS) or chondroitin sulfate A (CSA) impurities. In addition, we surveyed a selection of crude heparin samples received by the agency in 2008 and 2009 to determine average and extreme DS, CSA, and galactosamine weight percent levels. In the presence of these impurities and the variable heparin content in the crude heparin samples, spiked OSCS was reliably detected to the 0.1% w/w level using a plate reader. Finally, authentically OSCS contaminated heparin sodium API and crude samples were distinguished visually by color from control samples using the LPTP/heparinase test.

Immobilization of surface active compounds on polymer supports using glow discharge processess. 1. Sodium dodecyl sulfate on poly(propylene)

NARCIS (Netherlands)

Terlingen, J.G.A.; Terlingen, Johannes G.A.; Feijen, Jan; Hoffman, Allan S.

1993-01-01

A new method has been developed in which a reversibly adsorbed layer of a surfactant (sodium dodecyl sulfate, SDS) is covalently immobilized in one step onto a hydrophobic substrate (poly(propylene), PP) by applying an argon plasma treatment. The adsorption of SDS from aqueous solutions onto PP

Clinical findings and effect of sodium hydrogen carbonate in patients with glutathione synthetase deficiency.

Science.gov (United States)

Gündüz, Mehmet; Ünal, Özlem; Kavurt, Sumru; Türk, Emrecan; Mungan, Neslihan Önenli

2016-04-01

Glutathione synthetase (GS) deficiency is a rare inborn error of glutathione (GSH) metabolism manifested by severe metabolic acidosis, hemolytic anemia, neurological problems and massive excretion of pyroglutamic acid (5-oxoproline) in the urine. The disorder has mild, moderate, and severe clinical variants. We aimed to report clinical and laboratory findings of four patients, effect of sodium hydrogen carbonate treatment and long-term follow up of three patients. Urine organic acid analysis was performed with gas chromatography-mass spectrometry. Molecular genetic analysis was performed in three patients, mutation was found in two of them. Enzyme analysis was performed in one patient. Clinical and laboratory findings of four patients were evaluated. One patient died at 4 months old, one patient's growth and development are normal, two patients have developed intellectual disability and seizures in the long term follow up period. Three patients benefited from sodium hydrogen carbonate treatment. The clinical picture varies from patient to patient, so it is difficult to predict the prognosis and the effectiveness of treatment protocols. We reported long term follow up of four patients and demonstrated that sodium hydrogen carbonate is effective for treatment of chronic metabolic acidosis in GS deficieny.

Evaluation of feed COD/sulfate ratio as a control criterion for the biological hydrogen sulfide production and lead precipitation

International Nuclear Information System (INIS)

Velasco, Antonio; Ramirez, Martha; Volke-Sepulveda, Tania; Gonzalez-Sanchez, Armando; Revah, Sergio

2008-01-01

The ability of sulfate-reducing bacteria to produce hydrogen sulfide and the high affinity of sulfide to react with divalent metallic cations represent an excellent option to remove heavy metals from wastewater. Different parameters have been proposed to control the hydrogen sulfide production by anaerobic bacteria, such as the organic and sulfate loading rates and the feed COD/SO 4 2- ratio. This work relates the feed COD/SO 4 2- ratio with the hydrogen sulfide production and dissolved lead precipitation, using ethanol as carbon and energy source in an up-flow anaerobic sludge blanket reactor. A maximum dissolved sulfide concentration of 470 ± 7 mg S/L was obtained at a feed COD/SO 4 2- ratio of 2.5, with sulfate and ethanol conversions of approximately 94 and 87%, respectively. The lowest dissolved sulfide concentration (145 ± 10 mg S/L) was observed with a feed COD/SO 4 2- ratio of 0.67. Substantial amounts of acetate (510-1730 mg/L) were produced and accumulated in the bioreactor from ethanol oxidation. Although only incomplete oxidation of ethanol to acetate was observed, the consortium was able to remove 99% of the dissolved lead (200 mg/L) with a feed COD/SO 4 2- ratio of 1.5. It was found that the feed COD/SO 4 2- ratio could be an adequate parameter to control the hydrogen sulfide production and the consequent precipitation of dissolved lead

75 FR 37790 - Lauryl Sulfate Salts; Antimicrobial Registration Review Final Work Plan and Proposed Registration...

Science.gov (United States)

2010-06-30

..., and opens a 60-day public comment period on the proposed decision. Sodium lauryl sulfate (PC Code...% sodium lauryl sulfate and is registered by Kimberly-Clark Global Sales, LLC (EPA Reg. No. 9402-10). The... sulfate as an active ingredient were first registered in 1948 and sodium lauryl sulfate is widely used as...

Preparation of Barley Storage Protein, Hordein, for Analytical Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis

DEFF Research Database (Denmark)

Doll, Hans; Andersen, Bente

1981-01-01

The extraction, reduction, and alkylation of barley hordein for routine electrophoresis in sodium dodecyl sulfate-polyacrylamide gels were studied to set up a simple preparation procedure giving well-resolved bands in the electrophoresis gel. Hordein was extracted from single crushed seeds or flour...... by aqueous 50% propan-2-ol containing a Tris-borate buffer, pH 8.6. The presence of the buffer facilitates the consecutive complete reduction of the extracted protein in the alcohol. Reduction and alkylation in the buffer containing propan-2-ol give sharper bands in the electrophoresis than reduction...

Hydrogen bond strengths in phosphorylated and sulfated amino acid residues.

Directory of Open Access Journals (Sweden)

Chaya Rapp

Full Text Available Post-translational modification by the addition of an oxoanion functional group, usually a phosphate group and less commonly a sulfate group, leads to diverse structural and functional consequences in protein systems. Building upon previous studies of the phosphoserine residue (pSer, we address the distinct nature of hydrogen bonding interactions in phosphotyrosine (pTyr and sulfotyrosine (sTyr residues. We derive partial charges for these modified residues and then study them in the context of molecular dynamics simulation of model tripeptides and sulfated protein complexes, potentials of mean force for interacting residue pairs, and a survey of the interactions of modified residues among experimental protein structures. Overall, our findings show that for pTyr, bidentate interactions with Arg are particularly dominant, as has been previously demonstrated for pSer. sTyr interactions with Arg are significantly weaker, even as compared to the same interactions made by the Glu residue. Our work sheds light on the distinct nature of these modified tyrosine residues, and provides a physical-chemical foundation for future studies with the goal of understanding their roles in systems of biological interest.

Effects of sodium β-sitosteryl sulfate on the phase behavior of dipalmitoylphosphatidylcholine.

Science.gov (United States)

Kafle, Ananda; Misono, Takeshi; Bhadani, Avinash; Sakai, Kenichi; Kaise, Chihiro; Kaneko, Teruhisa; Sakai, Hideki

2018-01-01

We have studied the phase behavior of dipalmitoylphosphatidylcholine (DPPC) containing sodium β-sitosteryl sulfate (PSO 4 ). PSO 4 was found to lower the phase transition temperature of DPPC to a higher degree than cholesterol or β-sitosterol. It also gave rise to the formation of a modulated (ripple) phase (P β ) at low to moderate concentrations. At concentrations greater than 25 mol%, it completely changed the membrane into a fluid phase. This shows that PSO 4 is capable of disordering the hydrocarbon chains of PC efficiently. The characteristics of PSO 4 for fluidizing the membrane can be useful for the pharmaceutical and cosmetics industries. Copyright © 2017 Elsevier B.V. All rights reserved.

1 kWe sodium borohydride hydrogen generation system Part II: Reactor modeling

OpenAIRE

Zhang, Jinsong; Zheng, Yuan; Gore, Jay P; Mudawar, Issam; Fisher, Timothy

2007-01-01

Sodium borohydride (NaBH4) hydrogen storage systems offer many advantages for hydrogen storage applications. The physical processes inside a NaBH4 packed bed reactor involve multi-component and multi-phase flow and multi-mode heat and mass transfer. These processes are also coupled with reaction kinetics. To guide reactor design and optimization, a reactor model involving all of these processes is desired. A onedimensional numerical model in conjunction with the assumption of homogeneous cata...

Influence of Sodium Lauryl Sulfate and Tween 80 on Carbamazepine–Nicotinamide Cocrystal Solubility and Dissolution Behaviour

OpenAIRE

Ke Wang; Ning Qiao; Mingzhong Li

2013-01-01

The influence of the surfactants of sodium lauryl sulfate (SLS) and Tween 80 on carbamazepine–nicotinamide (CBZ–NIC) cocrystal solubility and dissolution behaviour has been studied in this work. The solubility of the CBZ–NIC cocrystal was determined by measuring the eutectic concentrations of the drug and the coformer. Evolution of the intrinsic dissolution rate (IDR) of the CBZ–NIC cocrystal was monitored by the UV imaging dissolution system during dissolution. Experimental results indicated...

Portulaca Extract Attenuates Development of Dextran Sulfate Sodium Induced Colitis in Mice through Activation of PPARγ

OpenAIRE

Kong, Rui; Luo, Hui; Wang, Nan; Li, Jingjing; Xu, Shizan; Chen, Kan; Feng, Jiao; Wu, Liwei; Li, Sainan; Liu, Tong; Lu, Xiya; Xia, Yujing; Shi, Yanhong; Zhou, Yingqun; He, Weigang

2018-01-01

Portulaca oleracea L. is a traditional Chinese medicine, which has been used as adjuvant therapy for inflammatory bowel disease (IBD). However, the mechanism of its activity in IBD still remains unclear. Since previous studies have documented the anti-inflammatory effect of peroxisome proliferator activated receptors-γ (PPAR-γ), Portulaca regulation of PPAR-γ in inflammation was examined in current study. Ulcerative colitis (UC) was generated by 5% dextran sulfate sodium (DSS) in mice and fou...

Toxicity detection of sodium nitrite, borax and aluminum potassium sulfate using electrochemical method.

Science.gov (United States)

Yu, Dengbin; Yong, Daming; Dong, Shaojun

2013-04-01

Based on the inhibition effect on the respiratory chain activity of microorganisms by toxicants, an electrochemical method has been developed to measure the current variation of a mediator in the presence of microorganisms contacted with a toxicant. Microelectrode arrays were adopted in this study, which can accelerate the mass transfer rate of an analyte to the electrode and also increase the total current signal, resulting in an improvement in detection sensitivity. We selected Escherichia coli as the testee and the standard glucose-glutamic acid as an exogenous material. Under oxygen restriction, the experiments in the presence of toxicant were performed at optimum conditions (solution pH 7.0, 37 degrees C and reaction for 3 hr). The resulting solution was then separated from the suspended microorganisms and was measured by an electrochemical method, using ferricyanide as a mediator. The current signal obtained represents the reoxidation of ferrocyanide, which was transformed to inhibiting efficiency, IC50, as a quantitative measure of toxicity. The IC50 values measured were 410, 570 and 830 mg/L for sodium nitrite, borax and aluminum potassium sulfate, respectively. The results show that the toxicity sequence for these three food additives is consistent with the value reported by other methods. Furthermore, the order of damage degree to the microorganism was also observed to be: sodium nitrite > borax > aluminum potassium sulfate > blank, according to the atomic force microscopy images of E. coli after being incubated for 3 hr with the toxic compound in buffer solutions. The electrochemical method is expected to be a sensitive and simple alternative to toxicity screening for chemical food additives.

A blend of Sodium Humate/SLES/Herbal Oils

Directory of Open Access Journals (Sweden)

Yeliz Akyiğit

2013-08-01

Full Text Available A blend of sodium humate (SH with anionic surfactants such as sodium lauryl ether sulfate (SLES was prepared by solution mixing at medium of herbal oils at 25, 50 and 75°C. Its miscibility studies were carried out by using physical techniques over an extended range of concentration and composition in buffer solution. In addition, to ascertain the state of miscibility of the blends, they were investigated by using UV-visible spectrophotometer and Fourier transform infrared (FTIR. These values revealed that the blend is miscible when the sodium humate content is more than %60 in the blend at all temperatures. There were no important differences in the characteristics of the blends at different temperatures.It was thought that the mechanism ofthe complex formation is realized by making strong intermolecular interaction like hydrogen bonds between the carbonyl groups in humic acid and hydroxyl groups in fatty acids.

τ - hydrogen phosphate of zirconia in sodium salt form and some of its properties

International Nuclear Information System (INIS)

Fernandez V, S.M.; Ordonez R, E.

2004-01-01

It is reported the obtaining and characterization in the sodium salt form of the τ-hydrogen phosphate of zirconium in sodium form, this compound it was synthesized, for a new technique developed in the laboratory of Dept. of Chemistry of the ININ. The characterization was carried out for XRD, IR, Sem and EDS the thermal gravimetric analysis is also reported. (Author)

Evaluation of feed COD/sulfate ratio as a control criterion for the biological hydrogen sulfide production and lead precipitation

Energy Technology Data Exchange (ETDEWEB)

Velasco, Antonio [Direccion General del Centro Nacional de Investigacion y Capacitacion Ambiental-Instituto Nacional de Ecologia, Av. San Rafael Atlixco 186, Col. Vicentina. Iztapalapa, Mexico 09340, D.F. (Mexico)], E-mail: jvelasco@ine.gob.mx; Ramirez, Martha [Direccion General del Centro Nacional de Investigacion y Capacitacion Ambiental-Instituto Nacional de Ecologia, Av. San Rafael Atlixco 186, Col. Vicentina. Iztapalapa, Mexico 09340, D.F. (Mexico); Volke-Sepulveda, Tania [Departamento de Biotecnologia, UAM-Cuajimalpa, San Rafael Atlixco 186, Col. Vicentina. Iztapalapa, Mexico 09340, D.F. (Mexico); Gonzalez-Sanchez, Armando [Departamento de Ingenieria de Procesos, Universidad Autonoma Metropolitana-Iztapalapa, UAM-Cuajimalpa, San Rafael Atlixco 186, Col. Vicentina. Iztapalapa, Mexico 09340, D.F. (Mexico); Revah, Sergio [Departamento de Procesos y Tecnologia, UAM-Cuajimalpa, San Rafael Atlixco 186, Col. Vicentina. Iztapalapa, Mexico 09340, D.F. (Mexico)

2008-03-01

The ability of sulfate-reducing bacteria to produce hydrogen sulfide and the high affinity of sulfide to react with divalent metallic cations represent an excellent option to remove heavy metals from wastewater. Different parameters have been proposed to control the hydrogen sulfide production by anaerobic bacteria, such as the organic and sulfate loading rates and the feed COD/SO{sub 4}{sup 2-} ratio. This work relates the feed COD/SO{sub 4}{sup 2-} ratio with the hydrogen sulfide production and dissolved lead precipitation, using ethanol as carbon and energy source in an up-flow anaerobic sludge blanket reactor. A maximum dissolved sulfide concentration of 470 {+-} 7 mg S/L was obtained at a feed COD/SO{sub 4}{sup 2-} ratio of 2.5, with sulfate and ethanol conversions of approximately 94 and 87%, respectively. The lowest dissolved sulfide concentration (145 {+-} 10 mg S/L) was observed with a feed COD/SO{sub 4}{sup 2-} ratio of 0.67. Substantial amounts of acetate (510-1730 mg/L) were produced and accumulated in the bioreactor from ethanol oxidation. Although only incomplete oxidation of ethanol to acetate was observed, the consortium was able to remove 99% of the dissolved lead (200 mg/L) with a feed COD/SO{sub 4}{sup 2-} ratio of 1.5. It was found that the feed COD/SO{sub 4}{sup 2-} ratio could be an adequate parameter to control the hydrogen sulfide production and the consequent precipitation of dissolved lead.

USING RESPIROMETRY TO MEASURE HYDROGEN UTILIZATION IN SULFATE REDUCING BACTERIA IN THE PRESENCE OF COPPER AND ZINC

Science.gov (United States)

A respirometric method has been developed to measure hydrogen utilization by sulfate reducing bacteria (SRB). One application of this method has been to test inhibitory metals effects on the SRB culture used in a novel acid mine drainage treatment technology. As a control param...

Ferrous sulfate, but not iron polymaltose complex, aggravates local and systemic inflammation and oxidative stress in dextran sodium sulfate-induced colitis in rats

Directory of Open Access Journals (Sweden)

Toblli JE

2015-05-01

Full Text Available Jorge E Toblli, Gabriel Cao, Margarita Angerosa Laboratory of Experimental Medicine, Hospital Alemán, School of Medicine, University of Buenos Aires, Buenos Aires, Argentina Background and aims: Iron deficiency is common in inflammatory bowel disease, yet oral iron therapy may worsen the disease symptoms and increase systemic and local oxidative stress. The aim of this study was to compare the effects of oral ferrous sulfate and iron polymaltose complex on inflammatory and oxidative stress markers in colitic rats.Methods: Animals were divided into four groups with ten animals each. Rats of three groups received dextran sodium sulfate to induce colitis and animals of two of these groups received 5 mg iron/kg of body weight a day, as ferrous sulfate or iron polymaltose complex, for 7 days. Gross colon anatomy, histology of colon and liver, stainings of L-ferritin, Prussian blue, hepcidin, tumor necrosis factor-α, and interleukin-6, as well serum levels of liver enzymes, inflammatory markers, and iron markers, were assessed.Results: Body weight, gross anatomy, crypt injury and inflammation scores, inflammatory parameters in liver and colon, as well as serum and liver hepcidin levels were not significantly different between colitic animals without iron treatment and colitic animals treated with iron polymaltose complex. In contrast, ferrous sulfate treatment caused significant worsening of these parameters. As opposed to ferrous sulfate, iron polymaltose complex caused less or no additional oxidative stress in the colon and liver compared to colitic animals without iron treatment.Conclusion: Iron polymaltose complex had negligible effects on colonic tissue erosion, local or systemic oxidative stress, and local or systemic inflammation, even at high therapeutic doses, and may thus represent a valuable oral treatment of iron deficiency in inflammatory bowel disease. Keywords: preclinical, oral iron treatment, tolerability, colonic tissue erosion

Have you tried spermine? A rapid and cost-effective method to eliminate dextran sodium sulfate inhibition of PCR and RT-PCR

DEFF Research Database (Denmark)

Krych, Lukasz; Kot, Witold; Bendtsen, Katja M. S.

2018-01-01

The Dextran Sulfate Sodium (DSS) induced colitis mouse model is commonly used to investigate human inflammatory bowel disease (IBD). Nucleic acid extracts originating from these animals are often contaminated with DSS, which is a strong inhibitor of many enzymatic based molecular biology reaction...

Study of the solubility of yttrium, praseodymium, neodymium, and gadolinium sulfates in the presence of sodium and potassium in sulfuric-phosphoric acid solutions at 20 deg C

International Nuclear Information System (INIS)

Lokshin, Eh.P.; Tareeva, O.A.; Kashulina, T.G.

2007-01-01

The solubility of yttrium, praseodymium, neodymium, and gadolinium sulfates in the presence of sodium and potassium ions and the composition of solid phases were studied at 20 deg C in relation to the concentration of acids in sulfuric acid, phosphoric acid, and sulfuric-phosphoric acid solutions containing up to 36 wt % H 2 SO 4 and 33.12 g 1 -1 H 3 PO 4 . The formation of double sulfates of praseodymium and neodymium with sodium and potassium ions, as well as of gadolinium sulfate with sodium ions of the composition 1 : 1 was revealed. In water at 20 deg C, the solubility products of PrNa(SO 4 ) 2 ·H 2 O, NdNa(SO 4 ) 2 ·H 2 O, GdNa(SO 4 ) 2 ·H 2 O, PrK(SO 4 ) 2 ·H 2 O, and NdK(SO 4 ) 2 ·H 2 O are found to be 7.28x10 -8 , 7.84x10 -8 , 3.09x10 -6 , 3.02x10 -6 , and 1.70x10 -6 , respectively [ru

Quantitative determination of a hydrogen impurity in a sodium coolant by hydride thermal dissociation

Science.gov (United States)

Ivanovskiy, M. N.; Pavlova, G. D.; Shmatko, B. A.; Milovidova, A. V.; Konovalov, E. YE.; Arnoldov, M. N.; Pleshivtsev, A. D.

1988-01-01

A molten sodium coolant containing hydrogen was heated in a vacuum at 450 C, and the gases generated pumped through a liquid nitrogen trap, and the H2 was then oxidized on a copper oxide substrate heated to 400 C. The accuracy of the method is 1.5 percent and the sensitivity is 1x10 to the -5 wt percent hydrogen.

By-Product Carrying Humidified Hydrogen: An Underestimated Issue in the Hydrolysis of Sodium Borohydride.

Science.gov (United States)

Petit, Eddy; Miele, Philippe; Demirci, Umit B

2016-07-21

Catalyzed hydrolysis of sodium borohydride generates up to four molecules of hydrogen, but contrary to what has been reported so far, the humidified evolved gas is not pure hydrogen. Elemental and spectroscopic analyses show, for the first time, that borate by-products pollute the stream as well as the vessel. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Genome-Wide Expression Analysis of Human In Vivo Irritated Epidermis: Differential Profiles Induced by Sodium Lauryl Sulfate and Nonanoic Acid

DEFF Research Database (Denmark)

Clemmensen, Anders; Andersen, Klaus E; Clemmensen, Ole

2010-01-01

the differential molecular events induced in the epidermis by different irritants, we collected sequential biopsies ((1/2), 4, and 24 hours after a single exposure and at day 11 after repeated exposure) from human volunteers exposed to either sodium lauryl sulfate (SLS) or nonanoic acid (NON). Gene expression...

The effectiveness of dentifrices without and with sodium lauryl sulfate on plaque, gingivitis and gingival abrasion : a randomized clinical trial

NARCIS (Netherlands)

Sälzer, S.; Rosema, N.A.M.; Martin, E.C.J.; Slot, D.E.; Timmer, C.J.; Dörfer, C.E.; van der Weijden, G.A.

2016-01-01

Objectives The aim of this study was to compare the efficacy of a dentifrice without sodium lauryl sulfate (SLS) to a dentifrice with SLS in young adults aged 18–34 years on gingivitis. Material and methods One hundred twenty participants (non-dental students) with a moderate gingival inflammation

A thermodynamic investigation on the binding of lysozme with sodium dodecyl sulfate

International Nuclear Information System (INIS)

Behbeheni, G.R.; Ramazani, S.; Gonbadi, K.

2013-01-01

The interaction of Sodium Dodecyl Sulfate (SDS) with hen egg lysozyme have been investigated at 298, 303 and 308 K in phosphate buffer at two different pH values (5 and 7), by isothermal titration calorimetry. The calorimetric data analysis allows the measurement of the complete set of thermodynamic parameters. The negative SDS ion binds to positive residues, neutralizes the protein surface charges and leads to precipitation and turbidity of the solution. At low concentrations of SDS, the binding is mainly electrostatic, with some simultaneous interaction of the hydrophobic tail with nearby hydrophobic patches on the lysozyme. The enthalpies of denaturation at pH 7 are 180.47, 198.51 and 216.56 for 298, 303 and 308 K respectively. (author)

Induction of colitis in young rats by dextran sulfate sodium.

Science.gov (United States)

Vicario, María; Crespí, Mar; Franch, Angels; Amat, Concepció; Pelegrí, Carme; Moretó, Miquel

2005-01-01

Models using dextran sulfate sodium (DSS) to induce experimental colitis in rodents have been performed mostly in adult animals. For this reason, we aimed to develop a model of colitis in young rats. DSS was administered to 30-day-old rats at concentrations ranging from 0.5 to 5% in drinking water. Young rats were remarkably sensitive to DSS since clinical symptoms rapidly rose with 5% DSS and most animals died after the fifth day. With 1 and 2% DSS, the severity of mucosal lesions was also high on day 7, the animals showing leukocytosis and anemia. At 0.5% DSS, leukocytosis and mild colonic lesions were induced. This concentration of DSS significantly increased myeloperoxidase activity and goblet cell number in the colon, indicating mucosal inflammation. Since food consumption was not reduced by 0.5% DSS, we suggest that this protocol can be used to study the effects of dietary supplements on intestinal inflammatory processes.

Hydrogen generation and storage from hydrolysis of sodium borohydride in batch reactors

Energy Technology Data Exchange (ETDEWEB)

Pinto, A.M.F.R.; Falcao, D.S. [Departamento de Eng. Quimica, Centro de Estudos de Fenomenos de Transporte, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); Silva, R.A.; Rangel, C.M. [Instituto Nacional de Engenharia e Tecnologia e Inovacao, Paco do Lumiar 22, 1649-038 (Portugal)

2006-08-15

The catalytic hydrolysis of alkaline sodium borohydride (NaBH{sub 4}) solution was studied using a non-noble; nickel-based powered catalyst exhibiting strong activity even after long time storage. This easy-to-prepare catalyst showed an enhanced activity after being recovered from previous use. The effects of temperature, NaBH{sub 4} concentration, NaOH concentration and pressure on the hydrogen generation rate were investigated. Particular importance has the effect of pressure, since the maximum reached pressure of hydrogen is always substantially lower than predictions (considering 100% conversion) due to solubility effects. The solubility of hydrogen is greatly enhanced by the rising pressure during reaction, leading to storage of hydrogen in the liquid phase. This effect can induce new ways of using this type of catalyst and reactor for the construction of hydrogen generators and even containers for portable and in situ applications. (author)

Sodium dodecyl sulfate-capillary gel electrophoresis of polyethylene glycolylated interferon alpha.

Science.gov (United States)

Na, Dong H; Park, Eun J; Youn, Yu S; Moon, Byung W; Jo, Yeong W; Lee, Sung H; Kim, Won-Bae; Sohn, Yeowon; Lee, Kang C

2004-02-01

Sodium dodecyl sulfate-capillary gel electrophoresis (SDS-CGE) using a hydrophilic replaceable polymer network matrix was applied to characterize the polyethylene glycol(PEG)ylated interferon alpha (PEG-IFN). The SDS-CGE method resulted in a clearer resolution in both the PEG-IFN species and the native IFN species. The distribution profile of PEGylation determined by SDS-CGE was consistent with that obtained by SDS-polyacrylamide gel electrophoresis (PAGE) with Coomassie blue or barium iodide staining. The result was also compared using matrix-assisted laser desorption/ionization-time of flight-mass spectrometry. SDS-CGE was also useful for monitoring the PEGylation reaction to optimize the reaction conditions, such as reaction molar ratio. This study shows the potential of SDS-CGE as a new method for characterizing the PEGylated proteins with advantages of speed, minimal sample consumption and high resolution.

Sulfate Reduction Remediation of a Metals Plume Through Organic Injection

International Nuclear Information System (INIS)

Phifer, M.A.

2003-01-01

Laboratory testing and a field-scale demonstration for the sulfate reduction remediation of an acidic/metals/sulfate groundwater plume at the Savannah River Site has been conducted. The laboratory testing consisted of the use of anaerobic microcosms to test the viability of three organic substrates to promote microbially mediated sulfate reduction. Based upon the laboratory testing, soybean oil and sodium lactate were selected for injection during the subsequent field-scale demonstration. The field-scale demonstration is currently ongoing. Approximately 825 gallons (3,123 L) of soybean oil and 225 gallons (852 L) of 60 percent sodium lactate have been injected into an existing well system within the plume. Since the injections, sulfate concentrations in the injection zone have significantly decreased, sulfate-reducing bacteria concentrations have significantly increased, the pH has increased, the Eh has decreased, and the concentrations of many metals have decreased. Microbially mediated sulfate reduction has been successfully promoted for the remediation of the acidic/metals/sulfate plume by the injection of soybean oil and sodium lactate within the plume

Intracellular sodium hydrogen exchange inhibition and clinical myocardial protection.

Science.gov (United States)

Mentzer, Robert M; Lasley, Robert D; Jessel, Andreas; Karmazyn, Morris

2003-02-01

Although the mechanisms underlying ischemia/reperfusion injury remain elusive, evidence supports the etiologic role of intracellular calcium overload and oxidative stress induced by reactive oxygen species. Activation of the sodium hydrogen exchanger (NHE) is associated with intracellular calcium accumulation. Inhibition of the NHE-1 isoform may attenuate the consequences of this injury. Although there is strong preclinical and early clinical evidence that NHE inhibitors may be cardioprotective, definitive proof of this concept in humans awaits the results of ongoing clinical trials.

Understanding oscillatory phenomena in molecular hydrogen generation via sodium borohydride hydrolysis.

Science.gov (United States)

Budroni, M A; Biosa, E; Garroni, S; Mulas, G R C; Marchettini, N; Culeddu, N; Rustici, M

2013-11-14

The hydrolysis of borohydride salts represents one of the most promising processes for the generation of high purity molecular hydrogen under mild conditions. In this work we show that the sodium borohydride hydrolysis exhibits a fingerprinting periodic oscillatory transient in the hydrogen flow over a wide range of experimental conditions. We disproved the possibility that flow oscillations are driven by supersaturation phenomena of gaseous bubbles in the reactive mixture or by a nonlinear thermal feedback according to a thermokinetic model. Our experimental results indicate that the NaBH4 hydrolysis is a spontaneous inorganic oscillator, in which the hydrogen flow oscillations are coupled to an "oscillophor" in the reactive solution. The discovery of this original oscillator paves the way for a new class of chemical oscillators, with fundamental implications not only for testing the general theory on oscillations, but also with a view to chemical control of borohydride systems used as a source of hydrogen based green fuel.

The problems of using a high-temperature sodium coolant in nuclear power plants for the production of hydrogen and other innovative applications

Science.gov (United States)

Sorokin, A. P.; Alexeev, V. V.; Kuzina, Ju. A.; Konovalov, M. A.

2017-11-01

The intensity of the hydrogen sources arriving from the third contour of installation in second in comparison with the hydrogen sources on NPP BN-600 increases by two - three order at using of high-temperature nuclear power plants with the sodium coolant (HT-NPP) for drawing of hydrogen and other innovative applications (gasification and a liquefaction of coal, profound oil refining, transformation of biomass to liquid fuel, in the chemical industry, metallurgy, the food-processing industry etc.). For these conditions basic new technological solutions are offered. The main condition of their implementation is raise of hydrogen concentration in the sodium coolant on two - three order in comparison with the modern NPP, in a combination to hydrogen removal from sodium and its pumping out through membranes from vanadium or niobium. The researches with use diffusive model have shown possibility to expel a casium inflow in sodium through a leakproof shell of fuel rods if vary such parameters as a material of fuel rods shell, its thickness and maintenance time at design of fuel rods for high-temperature NPP. However maintenance of high-temperature NPP in the presence of casium in sodium is inevitable at loss of leakproof of a fuel rods shell. In these conditions for minimisation of casium diffusion in structural materials it is necessary to provide deep clearing of sodium from cesium.

Liquid-liquid equilibrium of water + PEG 8000 + magnesium sulfate or sodium sulfate aqueous two-phase systems at 35°C: experimental determination and thermodynamic modeling

Directory of Open Access Journals (Sweden)

B. D. Castro

2005-09-01

Full Text Available Liquid-liquid extraction using aqueous two-phase systems is a highly efficient technique for separation and purification of biomolecules due to the mild properties of both liquid phases. Reliable data on the phase behavior of these systems are essential for the design and operation of new separation processes; several authors reported phase diagrams for polymer-polymer systems, but data on polymer-salt systems are still relatively scarce. In this work, experimental liquid-liquid equilibrium data on water + polyethylene glycol 8000 + magnesium sulfate and water + polyethylene glycol 8000 + sodium sulfate aqueous two-phase systems were obtained at 35°C. Both equilibrium phases were analyzed by lyophilization and ashing. Experimental results were correlated with a mass-fraction-based NRTL activity coefficient model. New interaction parameters were estimated with the Simplex method. The mean deviations between the experimental and calculated compositions in both equilibrium phases is about 2%.

Hydrolysis and regeneration of sodium borohydride (NaBH4) - A combination of hydrogen production and storage

Science.gov (United States)

Chen, W.; Ouyang, L. Z.; Liu, J. W.; Yao, X. D.; Wang, H.; Liu, Z. W.; Zhu, M.

2017-08-01

Sodium borohydride (NaBH4) hydrolysis is a promising approach for hydrogen generation, but it is limited by high costs, low efficiency of recycling the by-product, and a lack of effective gravimetric storage methods. Here we demonstrate the regeneration of NaBH4 by ball milling the by-product, NaBO2·2H2O or NaBO2·4H2O, with MgH2 at room temperature and atmospheric pressure without any further post-treatment. Record yields of NaBH4 at 90.0% for NaBO2·2H2O and 88.3% for NaBO2·4H2O are achieved. This process also produces hydrogen from the splitting of coordinate water in hydrated sodium metaborate. This compensates the need for extra hydrogen for generating MgH2. Accordingly, we conclude that our unique approach realizes an efficient and cost-effective closed loop system for hydrogen production and storage.

Removal of Sulfate Ion From AN-107 by Evaporation

International Nuclear Information System (INIS)

GJ Lumetta; GS Klinger; DE Kurath; RL Sell; LP Darnell; LR Greenwood; CZ Soderquist; MJ Steele; MW Urie; JJ Wagner

2000-01-01

Hanford low-activity waste solutions contain sulfate, which can cause accelerated corrosion of the vitrification melter and unacceptable operating conditions. A method is needed to selectively separate sulfate from the waste. An experiment was conducted to evaluate evaporation for removing sulfate ion from Tank AN-107 low-activity waste. Two evaporation steps were performed. In the first step, the volume was reduced by 55% while in the second step, the liquid volume was reduced another 22%. Analysis of the solids precipitated during these evaporations revealed that large amounts of sodium nitrate and nitrite co-precipitated with sodium sulfate. Many other waste components precipitated as well. It can be concluded that sulfate removal by precipitation is not selective, and thus, evaporation is not a viable option for removing sulfate from the AN-107 liquid

Solar Metal Sulfate-Ammonia Based Thermochemical Water Splitting Cycle for Hydrogen Production

Science.gov (United States)

Huang, Cunping (Inventor); T-Raissi, Ali (Inventor); Muradov, Nazim (Inventor)

2014-01-01

Two classes of hybrid/thermochemical water splitting processes for the production of hydrogen and oxygen have been proposed based on (1) metal sulfate-ammonia cycles (2) metal pyrosulfate-ammonia cycles. Methods and systems for a metal sulfate MSO.sub.4--NH3 cycle for producing H2 and O2 from a closed system including feeding an aqueous (NH3)(4)SO3 solution into a photoctalytic reactor to oxidize the aqueous (NH3)(4)SO3 into aqueous (NH3)(2)SO4 and reduce water to hydrogen, mixing the resulting aqueous (NH3)(2)SO4 with metal oxide (e.g. ZnO) to form a slurry, heating the slurry of aqueous (NH4)(2)SO4 and ZnO(s) in the low temperature reactor to produce a gaseous mixture of NH3 and H2O and solid ZnSO4(s), heating solid ZnSO4 at a high temperature reactor to produce a gaseous mixture of SO2 and O2 and solid product ZnO, mixing the gaseous mixture of SO2 and O2 with an NH3 and H2O stream in an absorber to form aqueous (NH4)(2)SO3 solution and separate O2 for aqueous solution, recycling the resultant solution back to the photoreactor and sending ZnO to mix with aqueous (NH4)(2)SO4 solution to close the water splitting cycle wherein gaseous H2 and O2 are the only products output from the closed ZnSO4--NH3 cycle.

Solution-mediated phase transformation of haloperidol mesylate in the presence of sodium lauryl sulfate.

Science.gov (United States)

Greco, Kristyn; Bogner, Robin

2011-09-01

Forming a salt is a common way to increase the solubility of a poorly soluble compound. However, the solubility enhancement gained by salt formation may be lost due to solution-mediated phase transformation (SMPT) during dissolution. The SMPT of a salt can occur due to a supersaturated solution near the dissolving surface caused by pH or other solution conditions. In addition to changes in pH, surfactants are also known to affect SMPT. In this study, SMPT of a highly soluble salt, haloperidol mesylate, at pH 7 in the presence of a commonly used surfactant, sodium lauryl sulfate (SLS), was investigated. Dissolution experiments were performed using a flow-through dissolution apparatus with solutions containing various concentrations of SLS. Compacts of haloperidol mesylate were observed during dissolution in the flow-through apparatus using a stereomicroscope. Raman microscopy was used to characterize solids. The dissolution of haloperidol mesylate was significantly influenced by the addition of sodium lauryl sulfate. In conditions where SMPT was expected, the addition of SLS at low concentrations (0.1-0.2 mM) reduced the dissolution of haloperidol mesylate. In solutions containing concentrations of SLS above the critical micelle concentration (CMC) (10-15 mM), the dissolution of haloperidol mesylate increased compared to below the CMC. The solids recovered from solubility experiments of haloperidol mesylate indicated that haloperidol free base precipitated at all concentrations of SLS. Above 5 mM of SLS, Raman microscopy suggested a new form, perhaps the estolate salt. The addition of surfactant in solids that undergo solution-mediated phase transformation can add complexity to the dissolution profiles and conversion.

Studies on sulfate attack: Mechanisms, test methods, and modeling

Science.gov (United States)

Santhanam, Manu

The objective of this research study was to investigate various issues pertaining to the mechanism, testing methods, and modeling of sulfate attack in concrete. The study was divided into the following segments: (1) effect of gypsum formation on the expansion of mortars, (2) attack by the magnesium ion, (3) sulfate attack in the presence of chloride ions---differentiating seawater and groundwater attack, (4) use of admixtures to mitigate sulfate attack---entrained air, sodium citrate, silica fume, and metakaolin, (5) effects of temperature and concentration of the attack solution, (6) development of new test methods using concrete specimens, and (7) modeling of the sulfate attack phenomenon. Mortar specimens using portland cement (PC) and tricalcium silicate (C 3S), with or without mineral admixtures, were prepared and immersed in different sulfate solutions. In addition to this, portland cement concrete specimens were also prepared and subjected to complete and partial immersion in sulfate solutions. Physical measurements, chemical analyses and microstructural studies were performed periodically on the specimens. Gypsum formation was seen to cause expansion of the C3S mortar specimens. Statistical analyses of the data also indicated that the quantity of gypsum was the most significant factor controlling the expansion of mortar bars. The attack by magnesium ion was found to drive the reaction towards the formation of brucite. Decalcification of the C-S-H and its subsequent conversion to the non-cementitious M-S-H was identified as the mechanism of destruction in magnesium sulfate attack. Mineral admixtures were beneficial in combating sodium sulfate attack, while reducing the resistance to magnesium sulfate attack. Air entrainment did not change the measured physical properties, but reduced the visible distress of the mortars. Sodium citrate caused a substantial reduction in the rate of damage of the mortars due to its retarding effect. Temperature and

User's manual of BISHOP. A Bi-Phase, Sodium-Hydrogen-Oxygen system, chemical equilibrium calculation program

International Nuclear Information System (INIS)

Okano, Yasushi; Yamaguchi, Akira

2001-07-01

In an event of sodium leakage in liquid metal fast breeder reactors, liquid sodium flows out of piping, and droplet combustion might occur under a certain environmental condition. The combustion heat and reaction products should be evaluated in the sodium fire analysis codes for investigating the influence of the sodium leak age and fire incident. In order to analyze the reaction heat and products, the multi-phase chemical equilibrium calculation program for a sodium, oxygen and hydrogen system has been developed. The developed numerical program is named BISHOP, which denotes 'Bi-Phase, Sodium-Hydrogen-Oxygen, Chemical Equilibrium Calculation Program'. The Gibbs free energy minimization method is used because of the following advantages. Chemical species are easily added and changed. A variety of thermodynamic states, such as isothermal and isentropic changes, can be dealt with in addition to constant temperature and pressure processes. In applying the free energy minimization method to solve the multi-phase sodium reaction system, three new numerical calculation techniques are developed. One is theoretical simplification of phase description in equation system, the other is to extend the Gibbs free energy minimization method to a multi-phase system, and the last is to establish the efficient search for the minimum value. The reaction heat and products at the equilibrium state can be evaluated from the initial conditions, such as temperature, pressure and reactants, using BISHOP. This report describes the thermochemical basis of chemical equilibrium calculations, the system of equations, simplification models, and the procedure to prepare input data and usage of BISHOP. (author)

The design and commissioning of cold trap purifying system of hydrogen meter sodium loop

International Nuclear Information System (INIS)

Zhao Zhaoyi; Jia Baoshan; Chen Xiaoming; Pan Fengguo

1993-01-01

The design feature and parameters of cold trap purifying system of hydrogen meter sodium loop and its commissioning results are reported and discussed. In order to adjust the flow easily,. the cold trap purifying system is arranged in the exit of the electromagnetic pump. It is composed of regenerator and the cold trap. The regenerator is above the cold trap. The high temperature sodium in the main-loop flows through the regenerator, in the entrance of the cold trap, its temperature is reduced to 180 degree C. After entering into the cold trap, the sodium flows to the purifying region by side, when it arrives the bottom of the trap, its temperature is reduced to 110 degree C. The cold trap is cooled by air. The temperature of the clean sodium rises nearby the main-loop's by the regenerator, and then it returns to the entrance of the electromagnetic pump. According to the commissioning results, the sodium's temperature of the cold trap could be reduced to 110 degree C by reducing the flow of the cold trap purifying system and the temperature of the main-loop, or increasing the air flow and cutting off the power supply of its heating. The authors think that the latter is more conformable with the design stipulation and with the requirement of the hydrogen meter experiment, and it can meet the requirements of the operation of the Nuclear Power Plant

Efficacy of formalin, hydrogen-peroxide, and sodium-chloride on fungal-infected rainbow-trout eggs

Science.gov (United States)

Schreier, Theresa M.; Rach, J.J.; Howe, G.E.

1996-01-01

Antifungal agents are essential for the maintenance of healthy stocks of fish and their eggs in intensive aquaculture operations. In the usa, formalin is the only fungicide approved for use in fish culture, however, hydrogen peroxide and sodium chloride have been granted low regulatory priority drug status by the united states food and drug administration (fda) and their use is allowed. We evaluated the efficacy of these fungicides for controlling fungal infections on rainbow trout eggs. A pilot study was conducted to determine the minimum water flow rate required to administer test chemicals accurately in heath incubators. A minimum water flow rate of 7.6 1 min(-1) was necessary to maintain treatment concentrations during flow-through chemical exposures, the antifungal activity of formalin, hydrogen peroxide, and sodium chloride was evaluated by treating uninfected and 10% fungal-infected (saprolegnia parasitica) rainbow trout eggs (oncorhynchus mykiss) for 15 min every other day until hatch. There were no significant differences among treatments in percent hatch or final infection for uninfected eggs receiving prophylactic chemical treatments, eggs of the negative control group (uninfected and untreated) had a mean hatch exceeding 86%, all chemical treatments conducted on the infected egg groups controlled the spread of fungus and improved hatching success compared with the positive control groups (infected and untreated), formalin treatments of 1000 and 1500 mu l 1(-1) and hydrogen peroxide treatments of 500 and 1000 mu l 1(-1) were the most effective. Sodium chloride treatments of 30000 mg 1(-1) improved fry hatch, but the compound was less effective at inhibiting fungal growths compared with hydrogen peroxide and formalin treatments.

Opiate-like excitatory effects of steroid sulfates and calcium-complexing agents given cerebroventricularly.

Science.gov (United States)

LaBella, F S; Havlicek, V; Pinsky, C

1979-01-12

Intracerebroventricular administration of 10--20 microgram of steroid-O-sulfates induced hypermotility, agitation, salivation, EEG abnormalities, stereotypies, wet dog shakes and seizures. Equivalent effects resulted from 30--200 microgram morphine sulfate (H2SO4 salt), 50 microgram EGTA or 300--400 microgram of sodium sulfate or phosphate, but not chloride, nitrate or acetate. Non-steroid sulfates, steroid glucuronides and steroid phosphates were inactive. Naloxone, previously found to antagonize the excitatory effects of androsterone sulfate, failed to antagonize those of cortisol sulfate, sodium sulfate or EGTA. These findings suggest a role for extracellular calcium ions and for sulfate derived from circulating steroids in central responses to opiates.

EPR study of gamma irradiated N-methyl taurine (C 3H 9NO 3S) and sodium hydrogen sulphate monohydrate (NaHSO 3·H 2O) single crystals

Science.gov (United States)

Yıldırım, İlkay; Karabulut, Bünyamin

2011-03-01

EPR study of gamma irradiated C 3H 9NO 3S and NaHSO 3.H 2O single crystals have been carried out at room temperature. There is one site for the radicals in C 3H 9NO 3S and two magnetically distinct sites for the radicals in NaHSO 3. The observed lines in the EPR spectra have been attributed to the species of SO3- and RH radicals for N-methyl taurine, and to the SO3- and OH radicals for sodium hydrogen sulfate monohydrate single crystals. The principal values of the g for SO3-, the hyperfine values of RH and OH proton splitting have been calculated and discussed.

Interaction between sodium dodecyl sulfate and membrane reconstituted aquaporins: A comparative study of spinach SoPIP2;1 and E. coli AqpZ

DEFF Research Database (Denmark)

Hansen, Jesper Schmidt; Vararattanavech, Ardcharaporn; Plasencia, Inés

2011-01-01

This study describes the interaction between sodium dodecyl sulfate (SDS) and membrane proteins reconstituted into large unilamellar lipid vesicles and detergent micelles studied by circular dichroism (CD) and polarity sensitive probe labeling. Specifically, we carried out a comparative study of ...

Inhibition of sulfate reduction in paddy soils

Energy Technology Data Exchange (ETDEWEB)

Vamos, R

1958-12-13

The hydrogen sulfide formed in waterlogged soils is a serious problem in rice cultivation. It inhibits the uptake of water and nutrients and may even cause root-rot. Results can best be obtained by preventing the formation of hydrogen sulfide. It is formed mainly by reduction of sulfate for which the cellulose-butyric acid fermentation provides the hydrogen source. Addition of ammonium or potassium nitrate prevents the formation of H/sub 2/S. The hydrogen produced by butyric acid fermentation is used to reduce nitrate and consequently cannot be utilized by the sulfate-reducing bacteria as a source of energy. 6 references.

Safety assessment of non-animal chondroitin sulfate sodium: Subchronic study in rats, genotoxicity tests and human bioavailability.

Science.gov (United States)

Miraglia, Niccolò; Bianchi, Davide; Trentin, Antonella; Volpi, Nicola; Soni, Madhu G

2016-07-01

Chondroitin sulfate, an amino sugar polymer made of glucuronic acid and N-acetyl-galactosamine, is used in dietary supplements to promote joint health. Commonly used chondroitin sulfate is of animal origin and can pose potential safety problems including bovine spongiform encephalopathy (BSE). The objective of the present study was to investigate potential adverse effects, if any, of microbial derived chondroitin sulfate sodium (CSS) in subchronic toxicity, genotoxicity and bioavailability studies. In the toxicity study, Sprague Dawley rats (10/sex/group) were gavaged with CSS at dose levels of 0, 250, 500 and 1000 mg/kg body weight (bw)/day for 90-days. No mortality or significant changes in clinical signs, body weights, body weight gain or feed consumption were noted. Similarly, no toxicologically relevant treatment-related changes in hematological, clinical chemistry, urinalysis and organ weights were noted. Macroscopic and microscopic examinations did not reveal treatment-related abnormalities. In vitro mutagenic and clastogenic potentials as evaluated by Ames assay, chromosomal aberration test and micronucleus assay did not reveal genotoxicity of CSS. In pharmacokinetic study in human, CSS showed higher absorption as compared to chondroitin sulfate of animal origin. The results of subchronic toxicity study supports the no-observed-adverse-effect level (NOAEL) for CSS as 1000 mg/kg bw/day, the highest dose tested. Copyright © 2016 Elsevier Ltd. All rights reserved.

Levels of ammonium, sulfate, chloride, calcium, and sodium in snow and ice from southern Greenland

International Nuclear Information System (INIS)

Busenberg, E.; Langway, C.C. Jr.

1979-01-01

Chemical analysis of surface snows and dated ice core samples from Dye 3, Greenland, suggests that the ammonium cation is a major constituent in all samples and that the annual ammonium levels present in the south Greenland samples have varied from 3.3 to 26.3 μg/kg between the seventeenth century and the present time. The annual range of 1974--1975 surface samples was between 3.8 and 8.8 μg/kg, while the mean was 5.7 +- 1.8 μ/kg. The recent large-scale uses of fixed nitrogen fertilizers and industrial pollution have apparently not affected the levels of ammonia reaching southern Greenland. The sodium and chloride present are predominantly derived from ocean spray, while more than 90% of the calcium is of continental origin. The levels of these three elements have not apparently been affected by human activity since the industrial revolution. Sulfate levels have increased dramatically since the industrial revolution, suggesting that sulfate of anthropogenic origin is the most important source of sulfate in modern snows from southern Greenland. The amount of the sulfuric acid neutralized by the ammonium cations was approximately 100% in the seventeenth and eighteenth centuries, dropping to approximately 20% in the 1974--1975 samples. These figures imply that there has been in increase in the acidity of precipitation in southern Greenland since the end of the eighteenth ce

A new concept of hydrogen production system for sodium cooled FBR

International Nuclear Information System (INIS)

Nakagiri, Toshio; Aoto, Kazumi; Hoshiya, Taiji

2004-01-01

A new thermo-chemical and electrolytic hybrid hydrogen production process (thermo-chemical and electrolytic Hybrid Hydrogen process in Lower Temperature range: HHLT) is newly proposed by the Japan Nuclear Cycle Development Institute (JNC) to realize the hydrogen production from water by using the heat generation of sodium cooled Fast Breeding Reactor (FBR). The HHLT process is based on the sulfuric acid (H 2 SO 4 ) synthesis and decomposition processes developed earlier (Westinghouse process), and sulfur trioxide (SO 3 ) decomposition process of HHLT is facilitated by electrolysis with ionic oxygen conductive solid electrolyte to reduce operating temperature 200degC-300degC lower than Westinghouse process. Decomposition processes of SO 3 were confirmed with the cell voltage lower than 0.5 V at 500degC-600degC using 8mol yttria stabilized zirconia (8molYSZ) solid electrolyte and platinum electrode. Therefore, total voltage required for HHLT is expected to be lower than 1.0 V, because the voltage required for sulfuric acid synthesis is about 0.5V. Thermal efficiency of HHLT based on chemical reactions was roughly estimated to be within the range of 35% to 55% under the influence of H 2 SO 4 concentration and heat recovery. These results show the possibility of development of a new hydrogen production process which needs low splitting voltage and has high efficiency at around 500degC, utilizing the heat generation of sodium cooled FBR. SO 3 splitting with the voltage lower than 0.5V was confirmed at about 500degC experimentally, and ideal thermal efficiency of the cycle based on chemical reactions was evaluated. Furthermore, test apparatus to substantiate whole process of HHLT was manufactured. (author)

Electrophoretic separation of alginic sodium diester and sodium hexametaphosphate in chondroitin sulfate that interfere with the cetylpyridinium chloride titration assay.

Science.gov (United States)

Weiguo, Zhang; Giancaspro, Gabriel; Adams, Kristie M; Neal-Kababick, James; Hildreth, Jana; Li, Aishan; Roman, Mark C; Betz, Joseph M

2014-01-01

The most commonly used chondroitin sulfate (CS) assay method is cetylpyridinium chloride (CPC) titration. Cellulose acetate membrane electrophoresis (CAME) is the technique used for detection of impurities in the U.S. Pharmacopeia's CS monograph. Because CPC titration is a relatively nonspecific quantitative technique, the apparent amount of CS as determined by CPC titration alone may not reflect the true amount of CS due to possible interference with the CPC assay by impurities that contain CPC titratable functional groups. When CAME is used in conjunction with CPC titration, certain non-CS and adulterants can be visualized and estimated, and a true value for CS can be assigned once the presence of these non-CS impurities has been ruled out. This study examines conjunct application of CPC and CAME in ascertaining CS assay and purity in the presence of certain adulterants. These include propylene glycol alginate sulfate sodium, known in commerce as alginic sodium diester (ASD), and Zero One (Z1), a water-soluble agent newly reported in the CS marketplace and subsequently identified as sodium hexametaphosphate. ASD, Z1, and CS are similar in physical appearance and solubility in water and ethanol. They are also titratable anions and form ionic pairs with CPC, therefore interfering with the CPC titration assay for CS CAME separates these adulterants from each other and from CS by differences in their electrophoretic mobility. CAME is able to detect these impurities in CS at levels as low as 0.66% by weight. Although it is recommended that a method for detecting impurities (e.g., CAME) be used in cormbination with relatively nonspecific assay methods such as CPC titration, this is seldom done in practice. Assay results for CS derived fromn CPC titration may, therefore, be misleading, leaving the CS supply chain vulnerable to adulteration. In this study, the authors investigated ASD and Z1 adulteration of CS and developed an electrophoretic separation of these

Bone sialoprotein II synthesized by cultured osteoblasts contains tyrosine sulfate

International Nuclear Information System (INIS)

Ecarot-Charrier, B.; Bouchard, F.; Delloye, C.

1989-01-01

Isolated mouse osteoblasts that retain their osteogenic activity in culture were incubated with [35S] sulfate. Two radiolabeled proteins, in addition to proteoglycans, were extracted from the calcified matrix of osteoblast cultures. All the sulfate label in both proteins was in the form of tyrosine sulfate as assessed by amino acid analysis and thin layer chromatography following alkaline hydrolysis. The elution behavior on DEAE-Sephacel of the major sulfated protein and the apparent Mr on sodium dodecyl sulfate gels were characteristic of bone sialoprotein II extracted from rat. This protein was shown to cross-react with an antiserum raised against bovine bone sialoprotein II, indicating that bone sialoprotein II synthesized by cultured mouse osteoblasts is a tyrosine-sulfated protein. The minor sulfated protein was tentatively identified as bone sialoprotein I or osteopontin based on its elution properties on DEAE-Sephacel and anomalous behavior on sodium dodecyl sulfate gels similar to those reported for rat bone sialoprotein I

Carbon-supported cobalt catalyst for hydrogen generation from alkaline sodium borohydride solution

Energy Technology Data Exchange (ETDEWEB)

Xu, Dongyan; Liu, Xinmin; Cao, Changqing; Guo, Qingjie [College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Dai, Ping [College of Electromechanical Engineering, Qingdao University of Science and Technology, Qingdao 266061 (China)

2008-08-01

Low cost transition metal catalysts with high performance are attractive for the development of on-board hydrogen generation systems by catalytic hydrolysis of sodium borohydride (NaBH{sub 4}) in fuel cell fields. In this study, hydrogen production from alkaline NaBH{sub 4} via hydrolysis process over carbon-supported cobalt catalysts was studied. The catalytic activity of the supported cobalt catalyst was found to be highly dependent on the calcination temperatures. The hydrogen generation rate increases with calcination temperatures in the range of 200-400 C, but a high calcination temperature above 500 C led to markedly decreased activity. X-ray diffraction patterns reveal that the catalysts experience phase transition from amorphous Co-B to crystalline cobalt hydroxide with increase in calcination temperatures. The reaction performance is also dependent on the concentration of NaBH{sub 4}, and the hydrogen generation rate increases for lower NaBH{sub 4} concentrations and decreases after reaching a maximum at 10 wt.% of NaBH{sub 4}. (author)

Antibrowning and antimicrobial properties of sodium acid sulfate in apple slices.

Science.gov (United States)

Fan, Xuetong; Sokorai, Kimberly J B; Liao, Ching-Hsing; Cooke, Peter; Zhang, Howard Q

2009-01-01

There are few available compounds that can both control browning and enhance microbial safety of fresh-cut fruits. In the present study, the antibrowning ability of sodium acid sulfate (SAS) on "Granny Smith" apple slices was first investigated in terms of optimum concentration and treatment time. In a separate experiment, the apple slices were treated with water or 3% of SAS, calcium ascorbate, citric acid, or acidified calcium sulfate for 5 min. Total plate count, color, firmness, and tissue damage were assessed during a 21-d storage at 4 degrees C. Results showed that the efficacy of SAS in inhibiting browning of apple slices increased with increasing concentration. A minimum 3% of SAS was needed to achieve 14 d of shelf life. Firmness was not significantly affected by SAS at 3% or lower concentrations. Antibrowning potential of SAS was similar for all treatment times ranging from 2 to 10 min. However, SAS caused some skin discoloration of apple slices. When cut surface of apple slices were stained with a fluorescein diacetate solution, tissue damage could be observed under a microscope even though visual damage was not evident. Among the antibrowning agents tested, SAS was the most effective in inhibiting browning and microbial growth for the first 14 d. Total plate count of samples treated with 3% SAS was significantly lower than those treated with calcium ascorbate, a commonly used antibrowning agent. Our results suggested that it is possible to use SAS to control browning while inhibiting the growth of microorganisms on the apple slices if the skin damage can be minimized. Practical Application: Fresh-cut apples have emerged as one of the popular products in restaurants, schools, and food service establishments as more consumers demand fresh, convenient, and nutritious foods. Processing of fresh-cut apples induces mechanical damage to the fruit and exposes apple tissue to air, resulting in the development of undesirable tissue browning. The fresh

The influence of the water chemistry regime of the third circuit on the corrosion hydrogen burden to the secondary sodium circuit in the steam generator model of BN-800 reactor

International Nuclear Information System (INIS)

Smykov, V.B.; Ermolaev, N.P.; Kolesnik, A.I.; Egorov, V.A.; Shevchenko, N.N.

1994-01-01

An experimental program was conducted to determine the influence of water chemistry on the corrosion hydrogen burden from the III circuit to the secondary sodium in sodium-heated rig of OTSG of NPP BN-800. Combined water chemistry has given the best passivative effect on steam-generating surfaces and smallest hydrogen burden to secondary sodium during start-up. Common hydrogen increasing in secondary sodium was less then 0.2 ppm. In case of AVT water chemistry (NH 3 +N 2 H 4 ) in III side of OTSG-rig the hydrogen level in secondary sodium was 1.0-1.2 ppm. It means that during first start-up at NPP BN-800 the common hydrogen level in secondary sodium may reaches 0.80-0.85 ppm. 4 figs.; 4 tabs

Pretreatment of clinical specimens with sodium dodecyl (lauryl) sulfate is not suitable for the mycobacteria growth indicator tube cultivation method.

OpenAIRE

Pfyffer, G E; Welscher, H M; Kissling, P

1997-01-01

When using the Mycobacteria Growth Indicator Tube (MGIT), pretreatment of clinical specimens with N-acetyl-L-cysteine-NaOH is recommended by the manufacturer. Processing of clinical specimens (n = 1,000) with sodium dodecyl (lauryl) sulfate-NaOH resulted in both poor recovery and delayed mean time to detection of acid-fast bacilli. Values were comparable to those obtained on solid media.

Sodium lauryl ether sulfate (SLES) degradation by nitrate-reducing bacteria.

Science.gov (United States)

Paulo, Ana M S; Aydin, Rozelin; Dimitrov, Mauricio R; Vreeling, Harm; Cavaleiro, Ana J; García-Encina, Pedro A; Stams, Alfons J M; Plugge, Caroline M

2017-06-01

The surfactant sodium lauryl ether sulfate (SLES) is widely used in the composition of detergents and frequently ends up in wastewater treatment plants (WWTPs). While aerobic SLES degradation is well studied, little is known about the fate of this compound in anoxic environments, such as denitrification tanks of WWTPs, nor about the bacteria involved in the anoxic biodegradation. Here, we used SLES as sole carbon and energy source, at concentrations ranging from 50 to 1000 mg L -1 , to enrich and isolate nitrate-reducing bacteria from activated sludge of a WWTP with the anaerobic-anoxic-oxic (A 2 /O) concept. In the 50 mg L -1 enrichment, Comamonas (50%), Pseudomonas (24%), and Alicycliphilus (12%) were present at higher relative abundance, while Pseudomonas (53%) became dominant in the 1000 mg L -1 enrichment. Aeromonas hydrophila strain S7, Pseudomonas stutzeri strain S8, and Pseudomonas nitroreducens strain S11 were isolated from the enriched cultures. Under denitrifying conditions, strains S8 and S11 degraded 500 mg L -1 SLES in less than 1 day, while strain S7 required more than 6 days. Strains S8 and S11 also showed a remarkable resistance to SLES, being able to grow and reduce nitrate with SLES concentrations up to 40 g L -1 . Strain S11 turned out to be the best anoxic SLES degrader, degrading up to 41% of 500 mg L -1 . The comparison between SLES anoxic and oxic degradation by strain S11 revealed differences in SLES cleavage, degradation, and sulfate accumulation; both ester and ether cleavage were probably employed in SLES anoxic degradation by strain S11.

Biodegradation of the anionic surfactant sodium dodecyl sulfate by local bacterial isolate

International Nuclear Information System (INIS)

Ibrahim, H.M.M.; NoorEl-Din, M.R.

2011-01-01

Anionic surfactants, e.g., sodium dodecyl sulfate (SDS), as a main components in the detergent and cosmetic industries, contribute significantly to the pollution profile of sewage and wastewaters of all kinds. The purpose of this study was to isolate local SDS degrading bacteria. Screening was carried out by the conventional enrichment culture technique. One bacterial isolate was obtained; this isolate was primarily defined as gram-negative rods . It was capable of degrading 100% of 1000 and 2000 mg/l of SDS after 6 days of incubation. The isolate exhibited maximum growth at SDS concentration 4000 mg/I, but it was significantly decreased at higher concentration (16000 mg/I).All the carbon sources being tested repressed the degradation ability. Sodium nitrate at concentration of 2.0 g/I was the best nitrogen source for growth and SDS biodegradation, it enhanced the degradation of 3000 mg/I SDS by 95%,i.e., by 32% upon the control (broth medium containing NH 4 Cl). SDS degradation by the bacterium was optimum at initial ph 8.5, incubation temperature 35 degree C, and inoculum size 2% (v/v). Under the optimized conditions, almost 98% of initial SDS concentration (4000 mg/l) was degraded after 120 h of incubation. Gamma irradiation did not improve the biodegradation ability of this bacterial isolate.

Recovery of Copper from Cyanidation Tailing by Flotation

Science.gov (United States)

Qiu, Tingsheng; Huang, Xiong; Yang, Xiuli

2016-02-01

In this work, sodium hypochlorite, hydrogen peroxide, sodium metabisulfite and copper sulfate as activators were investigated to lessen the depression effect of cyanide for deep-depressing chalcopyrite. The experimental results indicate that the copper recovery exceeded 94%, 84% and 97% at the dosage: sodium hypochlorite 3 mL/L, hydrogen peroxide 2 mL/L, sodium metabisulfite 2 × 10-3 mol/L and copper sulfate 1.67 × 10-4 mol/L, respectively. According to the results of zeta potential and Fourier transform infrared spectrum, it is suggested that chalcopyrite was depressed because of the chemical adsorption of cyanide on the chalcopyrite surfaces. Sodium hypochlorite, hydrogen peroxide and sodium metabisulfite can destroy Cu-C bond on the deep-depressing chalcopyrite surface by chemical reaction. Copper sulfate can activate deep-depressing chalcopyrite by copper ion adsorption.

Corrosion resistance of sodium sulfate coated cobalt-chromium-aluminum alloys at 900 C, 1000 C, and 1100 C

Science.gov (United States)

Santoro, G. J.

1979-01-01

The corrosion of sodium sulfate coated cobalt alloys was measured and the results compared to the cyclic oxidation of alloys with the same composition, and to the hot corrosion of compositionally equivalent nickel-base alloys. Cobalt alloys with sufficient aluminum content to form aluminum containing scales corrode less than their nickel-base counterparts. The cobalt alloys with lower aluminum levels form CoO scales and corrode more than their nickel-base counterparts which form NiO scales.

Sodium tetra-hydro-borate as energy/hydrogen carrier, its history

International Nuclear Information System (INIS)

Demirci, U.B.; Miele, Ph.

2009-01-01

Sodium tetra-hydro-borate NaBH 4 is considered as being a promising energy/hydrogen carrier. NaBH 4 is not a new compound. It has been discovered in 1940's by Prof. H.C. Brown, Nobel Laureate in Chemistry in 1979. NaBH 4 has thus a history and this history distinguishes the NaBH 4 utilisation as hydrogen carrier from that as energy carrier. In fact, the history of NaBH 4 (for both utilizations) can be divided into three periods, each period being characterised by specific societal challenges. Whereas during the first period the challenges were military and political, the challenges in the third period (i.e. at present) are energetic, environmental, civilian, social and political. The second period was rather calm for NaBH 4 even if it was intensively used as a reducing agent in organic chemistry. (authors)

Orally administered sodium 4-phenylbutyrate suppresses the development of dextran sulfate sodium-induced colitis in mice.

Science.gov (United States)

Ono, Kazuhiko; Nimura, Satoshi; Hideshima, Yuko; Nabeshima, Kazuki; Nakashima, Manabu

2017-12-01

Sodium 4-phenylbutyrate (PBA) exerts therapeutic effects in a wide range of pathologies. A previous study by the present authors revealed that intraperitoneal administration of PBA suppresses the onset of dextran sulfate sodium (DSS)-induced colitis in mice. In the present study, the effects of orally administered PBA are investigated, as this route of administration is more clinically relevant. The therapeutic efficacy of PBA (10 mg/12 h) in mice with experimental colitis was assessed based on the disease activity index, production of inflammatory cytokines, colon length and histopathological investigations. The results of the present study demonstrated a significantly higher survival rate in the PBA-treated group compared with the PBA-untreated (DSS control) group (P=0.0156). PBA treatment improved pathological indices of experimental colitis (P<0.05). Furthermore, the oral administration of PBA significantly inhibited the DSS-induced shortening of the colon (P<0.05) and overproduction of interleukin (IL)-1β and IL-6 (both P<0.05) as measured in colonic lavage fluids. A marked attenuation of the DSS-induced overproduction of tumor necrosis factor was also observed. For histopathological analysis, a marked decrease in mature goblet cells and increase in enlarged nuclei of the absorptive cells was observed in colon lesions of DSS control mice as compared with normal untreated mice. However, in the PBA-treated mice, no such lesions were observed and the mucosa resembled that of DSS-untreated mice. The results of the present study, combined with those results of a previous study, suggest that oral and intraperitoneal administration of PBA have similar preventative effects on DSS-induced colitis, achieved by suppressing its pathogenesis.

Effect of Sulfide Removal on Sulfate Reduction at pH 5 in a Hydrogen fed Gas-Lift Bioreactor

NARCIS (Netherlands)

Bijmans, M.F.M.; Dopson, M.; Lens, P.N.L.; Buisman, C.J.N.

2008-01-01

UNCORRECTED PROOF J. Microbiol. Biotechnol. (2007), 17(4), ¿ Effect of Sulfide Removal on Sulfate Reduction at pH 5 in a Hydrogen fed Gas-Lift Bioreactor Bijmans, Martijn F. M.1*, Mark Dopson2, Frederick Ennin1, Piet N. L. Lens1, and Cees J. N. Buisman1 1Sub Department of Environmental Technology,

One-Pot Synthesis of Some New Pyrido[2,3-d]pyrimidine Derivatives Catalyzed by Sodium Lauryl Sulfate in Aqueous Media

Directory of Open Access Journals (Sweden)

Sheng-Hui Li

2010-01-01

Full Text Available A series of pyrido[2,3-d]pyrimidine derivatives were synthesized by the three-component reaction of aromatic aldehyde, malononitrile and 6-amino-4-hydroxy-2-mercaptopyrimidine catalyzed by sodium lauryl sulfate (SDS in aqueous media. It was interesting that further aromatization took place automatically. This method provides several advantages such as easier work-up, milder reaction conditions and environmental friendly.

Evaluation of steam-to-sodium leak detectors in the sodium components test installation (SCTI)

Energy Technology Data Exchange (ETDEWEB)

McKee, J M; Simmons, W R

1975-07-01

Two nickel diffusion-membrane type hydrogen detectors were installed in the secondary sodium system of the Sodium Components Test Installation and evaluated during the 12-month performance test of the Modular Steam Generator (MSG). Hydrogen in the expansion tank cover gas was monitored with a gas chromatograph. During this period, numerous steam and hydrogen injections were made, simulating steam leaks into the sodium of an LMFBR steam generator. The response of the detectors was evaluated for leak sizes ranging from 10{sup -6} to 10{sup -4} 1b H{sub 2}O/sec, injection periods of 0.5 to 300 min, secondary sodium flow rates of 0.2 x 10{sup 6} to 1.5 x 10{sup 6} 1b/hr, and sodium temperatures of 400 to 950 deg. F. The response of the leak detection system was influenced significantly by two regimes of sodium temperature. Below 600 deg. F, the cover gas hydrogen detector gave the largest response; this is attributed to the long dissolution time of hydrogen bubbles relative to the transit time of hydrogen to the expansion tank. Above 600 deg. F, the hydrogen apparently dissolved rapidly and the detectors were much more effective in the sodium than in the cover gas. At least 75% of the hydrogen and 50% of the oxygen content of injected steam appeared as detectable activity if the reaction products were dispersed in the sodium stream and the sodium was above 600 deg. F. Hydrogen injections into semi-stagnant sodium at the MSG tube sheets were detected with better sensitivity than steam injections into the main sodium stream. It appeared that high local concentrations of hydrogen were quickly carried to the nearest detector by upward currents created by the injected gas. The alarm system functioned as expected, 2.1 ppb/min being the smallest rate-of-rise in hydrogen concentration to give an automatic alarm. With more sensitive rate-of-rise alarm settings, leaks as small as 2 x 10{sup -5} 1b H{sub 2}O/sec could be detected in a system such as the Clinch River Breeder

Evaluation of steam-to-sodium leak detectors in the sodium components test installation (SCTI)

International Nuclear Information System (INIS)

McKee, J.M.; Simmons, W.R.

1975-01-01

Two nickel diffusion-membrane type hydrogen detectors were installed in the secondary sodium system of the Sodium Components Test Installation and evaluated during the 12-month performance test of the Modular Steam Generator (MSG). Hydrogen in the expansion tank cover gas was monitored with a gas chromatograph. During this period, numerous steam and hydrogen injections were made, simulating steam leaks into the sodium of an LMFBR steam generator. The response of the detectors was evaluated for leak sizes ranging from 10 -6 to 10 -4 1b H 2 O/sec, injection periods of 0.5 to 300 min, secondary sodium flow rates of 0.2 x 10 6 to 1.5 x 10 6 1b/hr, and sodium temperatures of 400 to 950 deg. F. The response of the leak detection system was influenced significantly by two regimes of sodium temperature. Below 600 deg. F, the cover gas hydrogen detector gave the largest response; this is attributed to the long dissolution time of hydrogen bubbles relative to the transit time of hydrogen to the expansion tank. Above 600 deg. F, the hydrogen apparently dissolved rapidly and the detectors were much more effective in the sodium than in the cover gas. At least 75% of the hydrogen and 50% of the oxygen content of injected steam appeared as detectable activity if the reaction products were dispersed in the sodium stream and the sodium was above 600 deg. F. Hydrogen injections into semi-stagnant sodium at the MSG tube sheets were detected with better sensitivity than steam injections into the main sodium stream. It appeared that high local concentrations of hydrogen were quickly carried to the nearest detector by upward currents created by the injected gas. The alarm system functioned as expected, 2.1 ppb/min being the smallest rate-of-rise in hydrogen concentration to give an automatic alarm. With more sensitive rate-of-rise alarm settings, leaks as small as 2 x 10 -5 1b H 2 O/sec could be detected in a system such as the Clinch River Breeder Reactor Plant. A preliminary

The MOAHLFA index of irritant sodium lauryl sulfate reactions: first results of a multicentre study on routine sodium lauryl sulfate patch testing.

Science.gov (United States)

Uter, Wolfgang; Geier, Johannes; Becker, Detlef; Brasch, Jochen; Löffler, Harald

2004-01-01

In a multicentre study of the German Contact Dermatitis Research Group, sodium lauryl sulfate (SLS) 0.25% and 0.5% aq. has been added to routine allergen patch tests to assess its properties as a convenient diagnostic indicator of individual susceptibility to irritation at the time of patch testing. Previous studies indicated that irritant SLS reactivity may be related to individual factors such as age and sex. As these factors are, in turn, among the important predictors of contact allergy to many allergens, e.g. summarized in the 'MOAHLFA index', the impact of the MOAHLFA factors on irritant SLS patch test reactivity, and thus a potential for confounding, was assessed in the 5971 participating patients. As a result of 2 logistic regression analyses with an irritant reaction to 0.25% and 0.5% SLS, respectively, as outcome, male sex was identified as a relatively weak but significant risk factor (OR 1.38), while age 40 years or older was an even weaker risk factor (OR 1.22 and 1.15, respectively). Upon detailed analysis, no clear age gradient could, however, be identified. 1-day exposure time almost halved the odds of an irritant SLS reaction. In conclusion, this type of SLS patch test can be regarded as robust, indicating individual irritability relatively independent from the individual factors analysed here.

Sulfate Recognition by Persistent Crystalline Capsules with Rigidified Hydrogen Bonding Cavities

International Nuclear Information System (INIS)

Custelcean, Radu; Remy, Priscilla; Jiang, Deen; Bonnesen, Peter V; Moyer, Bruce A

2008-01-01

electivity is a fundamental property of pervasive importance in chemistry and biology as reflected in phenomena as diverse as membrane transport, catalysis, sensing, adsorption, complexation, and crystallization. Although the key principles of complementarity and preorganization governing the binding interactions underlying such phenomena were delineated long ago, truly profound selectivity has proven elusive by design in part because synthetic molecular architectures are neither maximally complementary for binding target species nor sufficiently rigid. Even if a host molecule possesses a high degree of complementarity for a guest species, it all too often can distort its structure or even rearrange its conformation altogether to accommodate competing guests. One approach taken by researchers to overcome this challenge has been to devise extremely rigid molecules that bind species within complementary cavities. Although examples have been reported to demonstrate the principle, such cases are not generally of practical utility, because of inefficient synthesis and often poor kinetics. Alternatively, flexible building blocks can be employed, but then the challenge becomes one of locking them in place. Taking a cue from natural binding agents that derive their rigidity from a network of molecular interactions, especially hydrogen bonding, we present herein an example of a crystalline, self-assembled capsule that binds sulfate by a highly complementary array of rigidified hydrogen bonds (H-bonds). Although covalent or self-assembled capsules have been previously employed as anion hosts, they typically lack the strict combination of complementarity and rigidity required for high selectivity. Furthermore, the available structural data for these systems is either restricted to a limited number of anions of similar size and shape, or varies significantly from one anion to another, which hampers the rationalization of the observed selectivity. We have been employing

Dextran Sulfate Sodium Inhibits Alanine Synthesis in Caco-2 Cells

Directory of Open Access Journals (Sweden)

Carolyn M. Slupsky

2011-04-01

Full Text Available To understand and characterize the pathogenic mechanisms of inflammatory bowel disease, dextran sulfate sodium (DSS has been used to induce acute and chronic colitis in animal models by causing intestinal epithelium damage. The mechanism of action of DSS in producing this outcome is not well understood. In an effort to understand how DSS might impact epithelial cell metabolism, we studied the intestinal epithelial cell line Caco-2 incubated with 1% DSS over 56 hours using 1H NMR spectroscopy. We observed no difference in cell viability as compared to control cultures, and an approximately 1.5-fold increase in IL-6 production upon incubation with 1% DSS. The effect on Caco-2 cell metabolism as measured through changes in the concentration of metabolites in the cell supernatant included a three-fold decrease in the concentration of alanine. Given that the concentrations of other amino acids in the cell culture supernatant were not different between treated and control cultures over 56 hours suggest that DSS inhibits alanine synthesis, specifically alanine aminotransferase, without affecting other key metabolic pathways. The importance of alanine aminotransferase in inflammatory bowel disease is discussed.

Benzalkonium chloride neutralizes the irritant effect of sodium dodecyl sulfate.

Science.gov (United States)

McFadden, J P; Holloway, D B; Whittle, E G; Basketter, D A

2000-11-01

When benzalkonium chloride (BKC), a cationic surfactant, is added to sodium dodecyl sulfate (SDS), an anionic surfactant, and used in patch testing, on the basis of their known physicochemical interaction, it is possible to predict that there will be a tendency towards a reduction in the expected irritant response when compared to SDS alone. The aim of this study was to investigate whether BKC could reduce the irritant response to SDS when applied after the SDS exposure. 54 non-atopic adult volunteers were recruited for the study. 20% SDS was applied for 2 h under occlusion. 1% BKC was then applied to the same site. Various controls, including SDS application followed by water for 2 h, were included. The irritant reaction was assessed at 24 h and 48 h. 40 of the 54 subjects had some reaction when SDS was applied for 2 h followed by either benzalkonium chloride or water control under occlusion. In comparison to water control, where BKC was applied after SDS, 20 of the 40 responders had a weaker reaction but only 4 had a stronger response. This study shows that BKC applied to skin exposed to SDS attenuates the resulting irritant reaction.

Hydrogen storage in sodium aluminum hydride.

Energy Technology Data Exchange (ETDEWEB)

Ozolins, Vidvuds; Herberg, J.L. (Lawrence Livermore National Laboratories, Livermore, CA); McCarty, Kevin F.; Maxwell, Robert S. (Lawrence Livermore National Laboratories, Livermore, CA); Stumpf, Roland Rudolph; Majzoub, Eric H.

2005-11-01

Sodium aluminum hydride, NaAlH{sub 4}, has been studied for use as a hydrogen storage material. The effect of Ti, as a few mol. % dopant in the system to increase kinetics of hydrogen sorption, is studied with respect to changes in lattice structure of the crystal. No Ti substitution is found in the crystal lattice. Electronic structure calculations indicate that the NaAlH{sub 4} and Na{sub 3}AlH{sub 6} structures are complex-ionic hydrides with Na{sup +} cations and AlH{sub 4}{sup -} and AlH{sub 6}{sup 3-} anions, respectively. Compound formation studies indicate the primary Ti-compound formed when doping the material at 33 at. % is TiAl{sub 3} , and likely Ti-Al compounds at lower doping rates. A general study of sorption kinetics of NaAlH{sub 4}, when doped with a variety of Ti-halide compounds, indicates a uniform response with the kinetics similar for all dopants. NMR multiple quantum studies of solution-doped samples indicate solvent interaction with the doped alanate. Raman spectroscopy was used to study the lattice dynamics of NaAlH{sub 4}, and illustrated the molecular ionic nature of the lattice as a separation of vibrational modes between the AlH{sub 4}{sup -} anion-modes and lattice-modes. In-situ Raman measurements indicate a stable AlH{sub 4}{sup -} anion that is stable at the melting temperature of NaAlH{sub 4}, indicating that Ti-dopants must affect the Al-H bond strength.

Hydrothermal Synthesis of Co-Ru Alloy Particle Catalysts for Hydrogen Generation from Sodium Borohydride

Directory of Open Access Journals (Sweden)

Marija Kurtinaitienė

2013-01-01

Full Text Available We report the synthesis of μm and sub-μm-sized Co, Ru, and Co-Ru alloy species by hydrothermal approach in the aqueous alkaline solutions (pH ≥ 13 containing CoCl2 and/or RuCl3, sodium citrate, and hydrazine hydrate and a study of their catalytic properties for hydrogen generation by hydrolysis of sodium borohydride solution. This way provides a simple platform for fabrication of the ball-shaped Co-Ru alloy catalysts containing up to 12 wt% Ru. Note that bimetallic Co-Ru alloy bowls containing even 7 at.% Ru have demonstrated catalytic properties that are comparable with the ones of pure Ru particles fabricated by the same method. This result is of great importance in view of the preparation of cost-efficient catalysts for hydrogen generation from borohydrides. The morphology and composition of fabricated catalyst particles have been characterized using scanning electron microscopy, energy dispersive X-ray diffraction, and inductively coupled plasma optical emission spectrometry.

Sulfate adsorption on goethite

Energy Technology Data Exchange (ETDEWEB)

Rietra, R P.J.J.; Hiemstra, T; Riemsdijk, W.H. van

1999-10-15

Recent spectroscopic work has suggested that only one surface species of sulfate is dominant on hematite. Sulfate is therefore a very suitable anion to test and develop adsorption models for variable charge minerals. The authors have studied sulfate adsorption on goethite covering a large range of sulfate concentrations, surface coverages, pH values, and electrolyte concentrations. Four different techniques were used to cover the entire range of conditions. For characterization at low sulfate concentrations, below the detection limit of sulfate with ICP-AES, the authors used proton-sulfate titrations at constant pH. Adsorption isotherms were studied for the intermediate sulfate concentration range. Acid-base titrations in sodium sulfate and electromobility were used for high sulfate concentrations. All the data can be modeled with one adsorbed species if it is assumed that the charge of adsorbed sulfate is spatially distributed in the interface. The charge distribution of sulfate follows directly from modeling the proton-sulfate adsorption stoichoimemtry sine this stoichiometry is independent of the intrinsic affinity constant of sulfate. The charge distribution can be related to the structure of the surface complex by use of the Pauling bond valence concept and is in accordance with the microscopic structure found by spectroscopy. The intrinsic affinity constant follows from the other measurements. Modeling of the proton-ion stoichoimetry with the commonly used 2-pK models, where adsorbed ions are treated as point charges, is possible only if at least two surface species for sulfate are used.

Sodium Dodecyl Sulfate (SDS-Loaded Nanoporous Polymer as Anti-Biofilm Surface Coating Material

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Sokol Ndoni

2013-02-01

Full Text Available Biofilms cause extensive damage to industrial settings. Thus, it is important to improve the existing techniques and develop new strategies to prevent bacterial biofilm formation. In the present study, we have prepared nanoporous polymer films from a self-assembled 1,2-polybutadiene-b-polydimethylsiloxane (1,2-PB-b-PDMS block copolymer via chemical cross-linking of the 1,2-PB block followed by quantitative removal of the PDMS block. Sodium dodecyl sulfate (SDS was loaded into the nanoporous 1,2-PB from aqueous solution. The SDS-loaded nanoporous polymer films were shown to block bacterial attachment in short-term (3 h and significantly reduce biofilm formation in long-term (1 week by gram-negative bacterium Escherichia coli. Tuning the thickness or surface morphology of the nanoporous polymer films allowed to extent the anti-biofilm capability.

Sodium Dodecyl Sulfate- Polyacrylamide Gel Electrophoresis (SDS- PAGE) of Irradiated Wheat Flour Proteins

International Nuclear Information System (INIS)

Souzan, R.M.

1999-01-01

Sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE) of wheat (Triticum aestivum L) flour have revealed 23 polypeptides of molecular weights between 170 and 11.57 KDa, High molecular weight glutenin subunits (LMW-GS) were distinguished. Densitometric analysis of the gel showed the effect of radiation on polypeptide constitution at radiation energy up to 7.5 kGy. Irradiation of wheat flour with 2.5 kGy have resulted in a slight increase in the molecular weight of wheat flour protein subunits. The increase of irradiation dose to 5.0 kGy has also induced an additional increase of molecular weight of protein subunits. The continuity in application of more radiation energy to a level of 7.5 kGy have resulted in the prevalence of degradation processes of all protein subunits more than the aggregation

3.2.1. Synthesis, crystal and molecular structure of catena-(bis(µ1-oxalic acid-µ3-hydrogen oxalate-di-aqua-sodium(I.

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Olga Kovalchukova*, Sergey Aldoshin, Andrey Utenyshev, Konstantin Bogenko, Valeriy Tkachev

2015-07-01

Full Text Available The crystal and molecular structure of catena-(bis(µ- oxalic acid-µ-hydrogen oxalate-di-aqua-sodium(I was detected by X-Ray analysis. The compound crystallizes in the triclinic space group P-1, with a(Å 6.2378(12; b(Å 7,1115(14; c(Å 10.489(2; α(° 94.65(3; β(° 100.12(3; γ(° 97.78(3. The sodium cation in the title compound is eight coordinated and forms a square antiprism. It is surrounded by two molecules of oxalic acid, one hydrogen oxalate anion and one water molecule. Both oxalic acid and hydrogen oxalate anion act as polydentate bridging ligands. Centrosymmetric sodium cations are bounded by hydrogen oxalate anions through a system of H bonds involving the molecules of oxalic acid. In the lattice, the 3D structure stabilized by H bonds is formed.

Impact of sodium lauryl sulfate in oral liquids on e-tongue measurements.

Science.gov (United States)

Immohr, Laura Isabell; Turner, Roy; Pein-Hackelbusch, Miriam

2016-12-30

During development of oral liquid medicines taste assessment is often required to evaluate taste and taste masking. Electronic tongue analysis can provide taste assessment of medicinal products but should only be conducted with medicines that interact with the instrument without damaging the sensor membranes or interfering with their electrical output so that robust data is generated. To explore the impact of a substance deemed unsuitable for electronic tongue analysis the influence of the anionic surfactant sodium lauryl sulfate (SLS), on the performance of the electronic tongue was conducted using electronic tongues equipped with self-developed PVC based sensors. The results showed a significant impact of SLS on all applied sensor types and an alteration of the sensor's sensitivity. Nevertheless, concentration dependent sensor responses could still be obtained and the sensor performance was not impacted negatively. Assessment of unsuitable substances should therefore be evaluated prior to performing electronic tongue analysis so that their impact is understood fully. Copyright © 2016 Elsevier B.V. All rights reserved.

An investigation of chitosan and sodium dodecyl sulfate interactions in acetic media

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Petrović Lidija B.

2016-01-01

Full Text Available Polymer/surfactant association is a cooperative phenomenon where surfactant binds to the polymer in the form of aggregates, usually through electrostatic or hydrophobic forces. As already known, polyelectrolytes may interact with oppositely charged surfactants through electrostatic attraction that results in polymer/surfactant complex formation. This behavior could be desirable in wide range of application of polymer/surfactant mixtures, such as improving colloid stability, gelling, emulsification and microencapsulation. In the present study surface tension, turbidity, viscosity and electrophoretic mobility measurements were used to investigate interactions of cationic polyelectrolyte chitosan (Ch and oppositely charged anionic surfactant, sodium dodecyl sulfate (SDS, in buffered water. Obtained results show the presence of interactions that lead to Ch/SDS complexes formation at all investigated pH and for all investigated polymer concentrations. Mechanisms of interaction, as well as characteristics of formed Ch/SDS complexes, are highly dependent on their mass ratio in the mixtures, while pH has no significant influence. [Projekat Ministarstva nauke Republike Srbije, br. II46010

Clinical application of extracellular fluid measurement using /sup 35/S-sodium sulfate

Energy Technology Data Exchange (ETDEWEB)

Shionoiri, H; Kondo, K; Uneda, S; Goto, E; Ono, Y [Yokohama City Univ. (Japan). Faculty of Medicine

1977-09-01

ECF (extracellular fluid volume) was measured by /sup 35/S-sodium sulfate and at the same time value of PV (plasma volume) was determined by /sup 131/I-RISA in each subject. In normal ECF was average of 181 ml/kg, 6.21 l/m/sup 2/ and PV was 49.1 ml/kg, 1.69 l/m/sup 2/. Both values of ECF and PV in essential hypertension were almost the same as those in normal. In congestive heart failure ECF was 232 ml/kg, 7.51 l/m/sup 2/ and PV was 55.8 ml/kg, 1.80 l/m/sup 2/. In the patients with ascites or edema, ECF was 256 ml/kg, 8.69 l/m/sup 2/ and PV was 53.0 ml/kg, 1.79 l/m/sup 2/. The results of the measurement by the two compounds also corresponded to the conditions of the patients who showed electrolytes disorders (ACTH deficiency, SIADH) and was improved by treatment.

Colonic and Hepatic Modulation by Lipoic Acid and/or N-Acetylcysteine Supplementation in Mild Ulcerative Colitis Induced by Dextran Sodium Sulfate in Rats

Science.gov (United States)

Moura, Fabiana Andréa; de Andrade, Kívia Queiroz; de Araújo, Orlando Roberto Pimentel; Santos, Juliana Célia de Farias

2016-01-01

Lipoic acid (LA) and N-acetylcysteine (NAC) are antioxidant and anti-inflammatory agents that have not yet been tested on mild ulcerative colitis (UC). This study aims to evaluate the action of LA and/or NAC, on oxidative stress and inflammation markers in colonic and hepatic rat tissues with mild UC, induced by dextran sodium sulfate (DSS) (2% w/v). LA and/or NAC (100 mg·kg·day−1, each) were given, once a day, in the diet, in a pretreatment phase (7 days) and during UC induction (5 days). Colitis induction was confirmed by histological and biochemical analyses (high performance liquid chromatography, spectrophotometry, and Multiplex®). A redox imbalance occurred before an immunological disruption in the colon. NAC led to a decrease in hydrogen peroxide (H2O2), malondialdehyde (MDA) levels, and myeloperoxidase activity. In the liver, DSS did not cause damage but treatments with both antioxidants were potentially harmful, with LA increasing MDA and LA + NAC increasing H2O2, tumor necrosis factor alpha, interferon gamma, and transaminases. In summary, NAC exhibited the highest colonic antioxidant and anti-inflammatory activity, while LA + NAC caused hepatic damage. PMID:27957238

Desalination and hydrogen, chlorine, and sodium hydroxide production via electrophoretic ion exchange and precipitation.

Science.gov (United States)

Shkolnikov, Viktor; Bahga, Supreet S; Santiago, Juan G

2012-08-28

We demonstrate and analyze a novel desalination method which works by electrophoretically replacing sodium and chloride in feed salt water with a pair of ions, calcium and carbonate, that react and precipitate out. The resulting calcium carbonate precipitate is benign to health, and can be filtered or settled out, yielding low ionic strength product water. The ion exchange and precipitation employs self-sharpening interfaces induced by movement of multiple ions in an electric field to prevent contamination of the product water. Simultaneously, the electrolysis associated with the electromigration produces hydrogen gas, chlorine gas, and sodium hydroxide. We conducted an experimental study of this method's basic efficacy to desalinate salt water from 100 to 600 mol m(-3) sodium chloride. We also present physicochemical models of the process, and analyze replacement reagents consumption, permeate recovery ratio, and energy consumption. We hypothesize that the precipitate can be recycled back to replacement reagents using the well-known, commercially implemented Solvay process. We show that the method's permeate recovery ratio is 58% to 46%, which is on par with that of reverse osmosis. We show that the method's energy consumption requirement over and above that necessary to generate electrolysis is 3 to 10 W h l(-1), which is on par with the energy consumed by state-of-the-art desalination methods. Furthermore, the method operates at ambient temperature and pressure, and uses no specialized membranes. The process may be feasible as a part of a desalination-co-generation facility: generating fresh water, hydrogen and chlorine gas, and sodium hydroxide.

1-Butyl-3-methylimidazolium hydrogen sulfate catalyzed in-situ transesterification of Nannochloropsis to fatty acid methyl esters

International Nuclear Information System (INIS)

Sun, Yingqiang; Cooke, Peter; Reddy, Harvind K.; Muppaneni, Tapaswy; Wang, Jun; Zeng, Zheling; Deng, Shuguang

2017-01-01

Highlights: • [Bmim][HSO_4] catalyzed in-situ transesterification of wet algae. • [Bmim][HSO_4] served as both effective solvent and excellent acid catalyst. • Proposed a mechanism for [Bmim][HSO_4] catalyzed in-situ transesterification. • Identified cell walls and lipid droplets in algae using confocal imaging tests. • Obtained crude biodiesel yield about 95% in 30 min at 200 °C. - Abstract: 1-Butyl-3-methylimidazolium hydrogen sulfate ([Bmim][HSO_4]) is used as a solvent and an acid catalyst for in-situ extractive transesterification of wet Nannochloropsis with methanol. The reaction is supposed to be a five-step process: (1) wet algae cell wall dissolves in ionic liquid at reaction temperatures; (2) hydrogen ions and sulfate ions release from the ionization of HSO_4"−. The hydrogen ions (H"+) act as catalysts for accelerating the reactive extraction of triglyceride from wet Nannochloropsis; (3) hydrogen ions and methanol molecules transfer from bulk to active site of cells without passing through cell wall that is dissolved by ionic liquid; (4) in-situ transesterification of lipid (mainly triglycerides) with methanol; and (5) products transfer from inside of algae cells to outside of cells. The crude biodiesel yield of [Bmim][HSO_4] catalyzed in-situ transesterification is about 95.28% at reaction temperature of 200 °C, reaction time of 30 min, mass ratio of [Bmim][HSO_4] to wet Nannochloropsis of 0.9:1, and a mass ratio of methanol to wet algae of 3:1. It decreases to 81.23% after [Bmim][HSO_4] is recycled for 4 times, which indicates that [Bmim][HSO_4] catalyzed in-situ transesterification is an economic approach for biodiesel production from wet algae.

Physical Compatibility of Magnesium Sulfate and Sodium Bicarbonate in a Pharmacy-compounded Bicarbonate-buffered Hemofiltration Solution

Science.gov (United States)

Moriyama, Brad; Henning, Stacey A.; Jin, Haksong; Kolf, Mike; Rehak, Nadja N.; Danner, Robert L.; Walsh, Thomas J.; Grimes, George J.

2011-01-01

PURPOSE To assess the physical compatibility of magnesium sulfate and sodium bicarbonate in a pharmacy-compounded bicarbonate-buffered hemofiltration solution used at the National Institutes of Health Clinical Center (http://www.cc.nih.gov). METHODS Two hemofiltration fluid formulations with a bicarbonate of 50 mEq/L and a magnesium of 1.5 mEq/L or 15 mEq/L were prepared in triplicate with an automated compounding device. The hemofiltration solution with a bicarbonate of 50 mEq/L and a magnesium of 1.5 mEq/L contains the maximum concentration of additives that we use in clinical practice. The hemofiltration solution of 15 mEq/L of magnesium and 50 mEq/L of bicarbonate was used to study the physicochemical properties of this interaction. The solutions were stored without light protection at 22 to 25 °C for 48 hours. Physical compatibility was assessed by visual inspection and microscopy. The pH of the solutions was assayed at 3 to 4 hours and 52 to 53 hours after compounding. In addition, electrolyte and glucose concentrations in the solutions were assayed at two time points after preparation: 3 to 4 hours and 50 to 51 hours. RESULTS No particulate matter was observed by visual and microscopic inspection in the compounded hemofiltration solutions at 48 hours. Electrolyte and glucose concentrations and pH were similar at both time points after solution preparation. CONCLUSION Magnesium sulfate (1.5 mEq/L) and sodium bicarbonate (50 mEq/L) were physically compatible in a pharmacy-compounded bicarbonate-buffered hemofiltration solution at room temperature without light protection at 48 hours. PMID:20237384

The anaerobic treatment of sulfate containing wastewater

NARCIS (Netherlands)

Visser, A.

1995-01-01

In the anaerobic treatment of sulfate containing wastewater sulfate reducing bacteria (SRB) will compete with methanogenic- (MB) and acetogenic bacteria (AB) for the available substrates such as hydrogen, acetate, propionate and butyrate. The outcome of this competition will

Alkaline sodium borohydride gel as a hydrogen source for PEMFC or an energy carrier for NaBH 4-air battery

Science.gov (United States)

Liu, B. H.; Li, Z. P.; Chen, L. L.

In this preliminary study, we tried to use sodium polyacrylate as the super absorbent polymer to form alkaline NaBH 4 gel and explored its possibilities for borohydride hydrolysis and borohydride electro-oxidation. It was found that the absorption capacity of sodium polyacrylate decreased with increasing NaBH 4 concentration. The formed gel was rather stable in the sealed vessel but tended to slowly decompose in open air. Hydrogen generation from the gel was carried out using CoCl 2 catalyst precursor solutions. Hydrogen generation rate from the alkaline NaBH 4 gel was found to be higher and impurities in hydrogen were less than that from the alkaline NaBH 4 solution. The NaBH 4 gel also successfully powered a NaBH 4-air battery.

Synthesis, physico-chemical and biomedical applications of sulfated Aegle marmelos gum: Green chemistry approach

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Manish Jindal

2017-05-01

Full Text Available The present investigation was aimed at obtaining a sulfated derivative of gum obtained from partially ripe fruits of Aegle marmelos employing the ultrasonication technique. Elemental analysis and FTIR-ATR studies confirmed successful sulfation. The molarity of sulfuric acid exerted maximum influence on the degree of substitution followed by reaction temperature and reaction time. The sulfated derivative showed higher swelling in both acidic and alkaline pH as compared to the unmodified gum. It also possessed higher negative zeta potential, higher viscosity, work of shear, firmness, consistency, cohesiveness and index of viscosity as compared to both unmodified gum as well as sodium alginate. Sulfated derivative was superior to unmodified gum and sodium alginate in terms of antimicrobial and anticoagulant activities. The sulfated sample appears to be a potential substitute over the unmodified gum sample and sodium alginate for modulating the physicochemical properties of food and drug release dosage forms.

Influence of sodium dodecyl sulfate concentration on the photocatalytic activity and dielectric properties of intercalated sodium dodecyl sulfate into Zn–Cd–Al layered double hydroxide

Energy Technology Data Exchange (ETDEWEB)

Ahmed, Abdullah Ahmed Ali, E-mail: abdullah2803@gmail.com [Department of Physics, Faculty of Applied Science, Thamar University, Dhamar 87246 (Yemen); Talib, Zainal Abidin [Department of Physics, Faculty of Science, Universiti Putra Malaysia, UPM, Serdang, Selangor 43400 (Malaysia); Hussein, Mohd Zobir [Advanced Materials and Nanotechnology Laboratory, Institute of Advanced Technology (ITMA), Universiti Putra Malaysia, UPM, Serdang, Selangor 43400 (Malaysia)

2015-02-15

Highlights: • Zn–Cd–Al–LDH–DS were synthesized with different SDS concentrations. • Photocatalytic activity of samples was improved by increasing SDS concentration. • Dielectric response of LDH can be described by anomalous low frequency dispersion. • The dc conductivity values were calculated for Zn–Cd–Al–LDH–DS samples. • ESR spectra exhibited the successful intercalation of DS molecule into LDH gallery. - Abstract: Sodium dodecyl sulfate (SDS) has been successfully intercalated into Zn–Cd–Al–LDH precursor with different SDS concentrations (0.2, 0.3, 0.4, 0.5 and 1 mol L{sup −1}) using the coprecipitation method at (Zn{sup 2+} + Cd{sup 2+})/Al{sup 3+} molar ratio of 13 and pH 8. The structural, morphological, texture and composition properties of the synthesized (Zn–Cd–Al–LDH–DS) nanostructure were investigated using powder X-ray diffraction (PXRD), scanning electron microscope (SEM), thermogravimetric analysis (TGA) and Fourier transform infrared (FT-IR), respectively. The photocatalytic activity of these materials was developed by increasing the concentration of intercalated SDS. The absorbance spectra have been used to detect an anion in the LDH interlayer before and after the intercalation process, which confirmed the presence of the dodecyl sulfate (DS{sup −}) anion into LDH gallery after intercalation. The anomalous low frequency dispersion (ALFD) has been used to describe the dielectric response of Zn–Cd–Al–LDH–DS nanostructure using the second type of universal power law. At low frequency, the polarization effect of electrodes caused the rising in dielectric constant and loss values. An important result of the dielectric measurements is the calculated dc conductivity values, which are new in dielectric spectroscopy of LDH materials. An important result of the electron spin resonance (ESR) spectra exhibited the successful intercalation of DS molecule into LDH gallery. The g-factor value was affected by

Metabolic Flexibility of Sulfate Reducing Bacteria

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Caroline M. Plugge

2011-05-01

Full Text Available Dissimilatory sulfate-reducing prokaryotes (SRB are a very diverse group of anaerobic bacteria that are omnipresent in nature and play an imperative role in the global cycling of carbon and sulfur. In anoxic marine sediments sulfate reduction accounts for up to 50% of the entire organic mineralization in coastal and shelf ecosystems where sulfate diffuses several meters deep into the sediment. As a consequence, SRB would be expected in the sulfate-containing upper sediment layers, whereas methanogenic Archaea would be expected to succeed in the deeper sulfate-depleted layers of the sediment. Where sediments are high in organic matter, sulfate is depleted at shallow sediment depths, and biogenic methane production will occur. In the absence of sulfate, many SRB ferment organic acids and alcohols, producing hydrogen, acetate, and carbon dioxide, and may even rely on hydrogen- and acetate-scavenging methanogens to convert organic compounds to methane. SRB can establish two different life styles, and these can be termed as sulfidogenic and acetogenic, hydrogenogenic metabolism. The advantage of having different metabolic capabilities is that it raises the chance of survival in environments when electron acceptors become depleted. In marine sediments, SRB and methanogens do not compete but rather complement each other in the degradation of organic matter.Also in freshwater ecosystems with sulfate concentrations of only 10-200 μM, sulfate is consumed efficiently within the top several cm of the sediments. Here, many of the δ-Proteobacteria present have the genetic machinery to perform dissimilatory sulfate reduction, yet they have an acetogenic, hydrogenogenic way of life.In this review we evaluate the physiology and metabolic mode of SRB in relation with their environment.

Study of structural, surface and hydrogen storage properties of boric acid mediated metal (sodium)-organic frameworks

Science.gov (United States)

Ozer, Demet; Köse, Dursun A.; Sahin, Onur; Oztas, Nursen A.

2018-04-01

Three boric acid mediated metal organic frameworks were synthesized by solution method with using succinic acid, fumaric acid and acetylene dicarboxylic acid as a ligand source and sodium as a metal source. The complexes were characterized by FT-IR, powder XRD, elemental analyses and single crystal measurements. The complexes with the formula, C4H18B2Na2O14, C4H16B2Na2O14 and C4H14B2Na2O14 were successfully obtained. BET surface area of complexes were calculated and found as 13.474 m2/g for catena-(tetrakis(μ2-hydroxo)-(μ2-trihydrogen borate)-(μ2-succinato)-di-sodium boric acid solvate), 1.692 m2/g for catena-(tetrakis(μ2-hydroxo)-(μ2-trihydrogen borate)-(μ2-fumarato)-di-sodium boric acid solvate) and 5.600 m2/g for catena-(tetrakis(μ2-hydroxo)-(μ2-trihydrogen borate)-(μ2-acetylenedicarboxylato)-di-sodium boric acid solvate). Hydrogen storage capacities of the complexes were also studied at 77 K 1 bar pressure and found as 0.108%, 0.033%, 0.021% by mass. When different ligands were used, the pore volume, pore width and surface area of the obtained complexes were changed. As a consequence, hydrogen storage capacities also changed.

Ni(0-CMC-Na Nickel Colloids in Sodium Carboxymethyl-Cellulose: Catalytic Evaluation in Hydrogenation Reactions

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Abdallah Karim

2011-01-01

Full Text Available A recyclable catalyst, Ni(0-CMC-Na, composed of nickel colloids dispersed in a water soluble bioorganic polymer, sodium carboxymethylcellulose (CMC-Na, was synthesized by a simple procedure from readily available reagents. The catalyst thus obtained is stable and highly active in alkene hydrogenations.

The corrosion properties of phosphate coating on AZ31 magnesium alloy: The effect of sodium dodecyl sulfate (SDS) as an eco-friendly accelerating agent

Energy Technology Data Exchange (ETDEWEB)

Amini, R. [Department of Polymer Engineering and Color Technology, AmirKabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Sarabi, A.A., E-mail: sarabi@aut.ac.ir [Department of Polymer Engineering and Color Technology, AmirKabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of)

2011-06-01

Sodium nitrite has been used as an accelerating agent in phosphating bath to improve its properties. However, it is well known that sodium nitrite is a carcinogenic component in phosphating sludge. In this study, it has been aimed to replace sodium nitrite by an environmentally friendly accelerating agent. To this end, sodium dodecyl sulfate (SDS) was used in phosphating bath to improve the phosphate coating formation on an AZ31 magnesium alloy. The effect of SDS/sodium nitrite ratio on the phosphated samples properties was also studied. Using field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), direct current (DC) polarization and electrochemical impedance spectroscopy (EIS) the properties of phosphated magnesium samples were studied. Results showed uniform phosphate coating formation on the magnesium sample mostly in hopeite phase composition. In addition, a denser and less permeable coating can be obtained at these conditions. The corrosion resistance of the phosphated samples was superiorly improved using higher SDS concentration in the phosphating bath.

The corrosion properties of phosphate coating on AZ31 magnesium alloy: The effect of sodium dodecyl sulfate (SDS) as an eco-friendly accelerating agent

International Nuclear Information System (INIS)

Amini, R.; Sarabi, A.A.

2011-01-01

Sodium nitrite has been used as an accelerating agent in phosphating bath to improve its properties. However, it is well known that sodium nitrite is a carcinogenic component in phosphating sludge. In this study, it has been aimed to replace sodium nitrite by an environmentally friendly accelerating agent. To this end, sodium dodecyl sulfate (SDS) was used in phosphating bath to improve the phosphate coating formation on an AZ31 magnesium alloy. The effect of SDS/sodium nitrite ratio on the phosphated samples properties was also studied. Using field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), direct current (DC) polarization and electrochemical impedance spectroscopy (EIS) the properties of phosphated magnesium samples were studied. Results showed uniform phosphate coating formation on the magnesium sample mostly in hopeite phase composition. In addition, a denser and less permeable coating can be obtained at these conditions. The corrosion resistance of the phosphated samples was superiorly improved using higher SDS concentration in the phosphating bath.

Effect of Microstructure on Hydrogen Diffusion in Weld and API X52 Pipeline Steel Base Metals under Cathodic Protection

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R. C. Souza

2017-01-01

Full Text Available The aim of this research was to evaluate the influence of microstructure on hydrogen permeation of weld and API X52 base metal under cathodic protection. The microstructures analyzed were of the API X52, as received, quenched, and annealed, and the welded zone. The test was performed in base metal (BM, quenched base metal (QBM, annealed base metal (ABM, and weld metal (WM. Hydrogen permeation flows were evaluated using electrochemical tests in a Devanathan cell. The potentiodynamic polarization curves were carried out to evaluate the corrosion resistance of each microstructure. All tests were carried out in synthetic soil solutions NS4 and NS4 + sodium thiosulfate at 25°C. The sodium thiosulfate was used to simulate sulfate reduction bacteria (SRB. Through polarization, assays established that the microstructure does not influence the corrosion resistance. The permeation tests showed that weld metal had lower hydrogen flow than base metal as received, quenched, and annealed.

Temporal and geographical distributions of epilithic sodium dodecyl sulfate-degrading bacteria in a polluted South Wales river

Energy Technology Data Exchange (ETDEWEB)

Anderson, D.J.; Day, M.J.; Russell, N.J.; White, G.F.

1988-02-01

Epilithic bacteria were isolated nonselectively from riverbed stones and examined by gel zymography for their ability to produce alkylsulfatase (AS) enzymes and thus to metabolize alkyl sulfate surfactants such as sodium dodecyl sulfate. The percentages of AS+ isolates from stone epilithon at five sites from the source to the river mouth were measured on five sampling days spread over 1 year. The results showed that (i) the prevalence of epilithic AS+ strains (as a percentage of all isolates) was much higher at polluted sites than at the source; (ii) when averaged over the whole river, percentages of AS+ strains were significantly higher at the end of summer compared with either the preceding or the following winter; (iii) analysis of site-sampling time interactions indicated that water quality factors (e.g., biochemical oxygen demand and dissolved oxygen concentration) rather than climatic factors determined the distributions of epilithic AS+ isolates; (iv) constitutive strains were the most prevalent (7.2% of all isolates), with smaller numbers of isolates with inducible (4.5%) and repressible (1.7%) enzymes.

Generation of Hydrogen, Lignin and Sodium Hydroxide from Pulping Black Liquor by Electrolysis

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Guangzai Nong

2015-12-01

Full Text Available Black liquor is generated in Kraft pulping of wood or non-wood raw material in pulp mills, and regarded as a renewable resource. The objective of this paper was to develop an effective means to remove the water pollutants by recovery of both lignin and sodium hydroxide from black liquor, based on electrolysis. The treatment of a 1000 mL of black liquor (122 g/L solid contents consumed 345.6 kJ of electric energy, and led to the generation of 30.7 g of sodium hydroxide, 0.82 g of hydrogen gas and 52.1 g of biomass solids. Therefore, the recovery ratios of elemental sodium and biomass solids are 80.4% and 76%, respectively. Treating black liquor by electrolysis is an environmentally friendly technology that can, in particular, be an alternative process in addressing the environmental issues of pulping waste liquor to the small-scale mills without black liquor recovery.

Human platelet as an independent unit for sulfate conjugation

International Nuclear Information System (INIS)

Khoo, B.Y.; Sit, K.H.; Wong, K.P.

1988-01-01

The human platelets possess a full complement of enzymes capable of synthesizing N-acetyldopamine (NADA) 35 sulfate from ATP, Mg ++ and sodium 35 sulfate. The pH optimum for this three-step overall sulfate conjugation (comprising of the ATP sulfurylase, APS kinase and phenolsulfotransferase reactions) is 8.6 and the reactions proceeded progressively for several hours. Both ATP and Mg ++ ions, above their respective optimal concentrations of 5 and 7 mM, inhibited the sulfate conjugation of NADA. The apparent Km values for NADA as determined by the phenolsulfotransferase (PST) and overall reactions were similar in magnitude being 2.6 and 4.8 μM, respectively, while that for sodium 35 sulfate was 202 μM. A comparison of these two activities in 62 platelet preparations of normal subjects showed that the rate of the PST reaction was generally higher than the overall reaction even though the PST assay was carried out at suboptimal concentration of PAPS. There was a positive correlation (r=0.82) between the two sets of data, suggesting that the PST reaction probably has some control over the rate of overall sulfate conjugation

Pd/C Synthesized with Citric Acid: An Efficient Catalyst for Hydrogen Generation from Formic Acid/Sodium Formate

Science.gov (United States)

Wang, Zhi-Li; Yan, Jun-Min; Wang, Hong-Li; Ping, Yun; Jiang, Qing

2012-01-01

A highly efficient hydrogen generation from formic acid/sodium formate aqueous solution catalyzed by in situ synthesized Pd/C with citric acid has been successfully achieved at room temperature. Interestingly, the presence of citric acid during the formation and growth of the Pd nanoparticles on carbon can drastically enhance the catalytic property of the resulted Pd/C, on which the conversion and turnover frequency for decomposition of formic acid/sodium formate system can reach the highest values ever reported of 85% within 160 min and 64 mol H2 mol−1 catalyst h−1, respectively, at room temperature. The present simple, low cost, but highly efficient CO-free hydrogen generation system at room temperature is believed to greatly promote the practical application of formic acid system on fuel cells. PMID:22953041

Methodology for Extraction of Remaining Sodium of Used Sodium Containers

International Nuclear Information System (INIS)

Jung, Minhwan; Kim, Jongman; Cho, Youngil; Jeong, Jiyoung

2014-01-01

Sodium used as a coolant in the SFR (Sodium-cooled Fast Reactor) reacts easily with most elements due to its high reactivity. If sodium at high temperature leaks outside of a system boundary and makes contact with oxygen, it starts to burn and toxic aerosols are produced. In addition, it generates flammable hydrogen gas through a reaction with water. Hydrogen gas can be explosive within the range of 4.75 vol%. Therefore, the sodium should be handled carefully in accordance with standard procedures even though there is a small amount of target sodium remainings inside the containers and drums used for experiment. After the experiment, all sodium experimental apparatuses should be dismantled carefully through a series of draining, residual sodium extraction, and cleaning if they are no longer reused. In this work, a system for the extraction of the remaining sodium of used sodium drums has been developed and an operation procedure for the system has been established. In this work, a methodology for the extraction of remaining sodium out of the used sodium container has been developed as one of the sodium facility maintenance works. The sodium extraction system for remaining sodium of the used drums was designed and tested successfully. This work will contribute to an establishment of sodium handling technology for PGSFR. (Prototype Gen-IV Sodium-cooled Fast Reactor)

Transport Modeling of Modified Magnetite Nanoparticles with Sodium Dodecyl Sulfate in a Saturated Sandy Soil

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Ahmad Farrokhian Firouzi

2017-02-01

Full Text Available Introduction: Nanoparticles due to their large specific area and reactivity recently have been used in several environmental remediation applications such as degradation of organic compounds and pesticides and adsorption of heavy metals and inorganic anions. Because of concern over potential threats of nanoparticle releases into the soil–water environment, a number of studies have been carried out to investigate the transport, retention and deposition of nanoparticles in saturated porous media. Many of these studies are based on measurements of transport in columns packed with idealized porous media consisting of spherical glass beads or sand. The nanoparticles are usually introduced into the column and breakthrough curve concentrations are measured at the column outlet. To examine the effect of various parameters on the transport of nanoparticles in porous medium, for convenience, all the parameters considered the same in the experiments, and only one parameter in the experiments is changed and investigated. Materials and Methods: The objective of this research is quantitative study of modified magnetite nanoparticles transport in saturated sand-repacked columns. The modified magnetite nanoparticles with Sodium dodecyl sulfate were synthesized following the protocol described by Si et al. (2004. The experimental setup included a suspension reservoir, Teflon tubing, a HPLC pump, and a glass column (2.5 cm i.d. and 20 cm height. Therefore, breakthrough curves of modified magnetite nanoparticles with Sodium dodecyl sulfate and chloride were determined under saturated conditions and influence of nanoparticles concentration (0.1 and 0.5 g.L-1 and pore velocity (pressure head of 2 and 10 cm on nanoparticles transport were investigated. For each medium bed, the background solution were first pumped through the column in the up-flow mode to obtain a steady flow state. Then, a tracer test was conducted by introducing CaCl2 solution into the column

Hydrogen isotopic messages in sulfate reducer lipids: a recorder of metabolic state?

Science.gov (United States)

Bradley, A. S.; Leavitt, W.; Zhou, A.; Cobban, A.; Suess, M.

2017-12-01

A significant range in microbial lipid 2H/1H ratios is observed in modern marine sediments. The magnitude of hydrogen isotope fractionation between microbial lipids and growth water (2ɛlipid-H2O) is hypothesized to relate to the central carbon and energy metabolism. These observations raise the possibility for culture independent identification of the dominant metabolic pathways operating in a given environment [Zhang et al. 2009]. One such metabolism we aim to track is microbial sulfate reduction. To-date, sulfate reducing bacteria have been observed to produce lipids that are depleted in fatty acid H-isotope composition, relative to growth water (2ɛlipid-H2O -50 to -175 ‰) [Campbell et al. 2009; Dawson et al. 2015; Osburn et al.], with recent work demonstrating a systematic relationship between lipid/water fractionation and growth rate when the electron-bifurcating NAD(P)(H) transhydrogenase (ebTH) activity was disrupted and the available electron requires the ebTH [Leavitt et al. 2016. Front Microbio]. Recent work in aerobic methylotrophs [Bradley et al. 2014. AGU] implicates non-bifurcating NAD(P)(H) transhydrogenase activity is a critical control on 2ɛlipid-H2O. This suggests a specific mechanism to control the range in fractionation is the ratio of intracellular NADPH/NADH/NADP/NAD in aerobes and perhaps the same in anaerobes with some consideration for FADH/FAD. Fundamentally this implies 2ɛlipid-H2O records intracellular redox state. In our sulfate reducer model system Desulfovibrio alaskensis strain G20 a key component of energy metabolism is the activity of ebTH. Nonetheless, this strain contains two independent copies of the genes, only one of which generates a distinctive isotopic phenotype [Leavitt et al. 2016. Front Microbio]. In this study we extend the recent work in G20 to continuous culture experiments comparing WT to nfnAB-2 transposon interruptions, where both organisms are cultivated continuously, at the rate of the slower growing mutant

A potential role for chondroitin sulfate/dermatan sulfate in arm regeneration in Amphiura filiformis.

Science.gov (United States)

Ramachandra, Rashmi; Namburi, Ramesh B; Dupont, Sam T; Ortega-Martinez, Olga; van Kuppevelt, Toin H; Lindahl, Ulf; Spillmann, Dorothe

2017-05-01

Glycosaminoglycans (GAGs), such as chondroitin sulfate (CS) and dermatan sulfate (DS) from various vertebrate and invertebrate sources are known to be involved in diverse cellular mechanisms during repair and regenerative processes. Recently, we have identified CS/DS as the major GAG in the brittlestar Amphiura filiformis, with high proportions of di- and tri-O-sulfated disaccharide units. As this echinoderm is known for its exceptional regeneration capacity, we aimed to explore the role of these GAG chains during A. filiformis arm regeneration. Analysis of CS/DS chains during the regeneration process revealed an increase in the proportion of the tri-O-sulfated disaccharides. Conversely, treatment of A. filiformis with sodium chlorate, a potent inhibitor of sulfation reactions in GAG biosynthesis, resulted in a significant reduction in arm growth rates with total inhibition at concentrations higher than 5 mM. Differentiation was less impacted by sodium chlorate exposure or even slightly increased at 1-2 mM. Based on the structural changes observed during arm regeneration we identified chondroitin synthase, chondroitin-4-O-sulfotransferase 2 and dermatan-4-O-sulfotransferase as candidate genes and sought to correlate their expression with the expression of the A. filiformis orthologue of bone morphogenetic factors, AfBMP2/4. Quantitative amplification by real-time PCR indicated increased expression of chondroitin synthase and chondroitin-4-O-sulfotransferase 2, with a corresponding increase in AfBMP2/4 during regeneration relative to nonregenerating controls. Our findings suggest that proper sulfation of GAGs is important for A. filiformis arm regeneration and that these molecules may participate in mechanisms controlling cell proliferation. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Glycyrrhetic Acid Ameliorates Dextran Sulfate Sodium-Induced Ulcerative Colitis in Vivo

Directory of Open Access Journals (Sweden)

Yong-Deok Jeon

2016-04-01

Full Text Available Glycyrrhizae Radix (GR is a Korean traditional herb medicine that is widely used in clinical health care. Glycyrrhetic acid (GA is an aglycone saponin extracted from GR that has anti-inflammatory, anti-cancer, and anti-viral effects. However, the anti-inflammatory effects of GA in colitis have not been reported. This study investigated the role of GA on ulcerative colitis in a dextran sulfate sodium (DSS-induced mouse colitis model. DSS-treated mice displayed weight loss and shortened colon length compared with control mice. Mice administered GA showed less weight loss and longer colon length than the DSS-treated group. Interleukin (IL-6, IL-1β, and tumor necrosis factor-alpha were decreased by GA treatment. GA treatment also reduced DSS-induced microscopic damage to colon tissue. GA regulates the phosphorylation of transcription factors including nuclear factor-kappa B (NF-κB and IκB alpha, and regulates the expression of cycloxygenase-2 and prostaglandin E2. GA thus showed beneficial effects in a mouse model of colitis, implicating GA might be a useful herb-derived medicine in the treatment of ulcerative colitis.

Solubility of hydrogen in aqueous solutions of sodium and potassium bicarbonate from 293 to 333 K

NARCIS (Netherlands)

Engel, D.C.; Engel, D.C.; Versteeg, Geert; van Swaaij, Willibrordus Petrus Maria

1996-01-01

An experimental study is presented of the hydrogen solubility in aqueous salt solutions containing sodium and potassium bicarbonate from 293 to 333 K. For this purpose, gas consumption measurements have been performed by determining the ultimate pressure decrease in an intensively stirred, high

Solubility of Hydrogen in Aqueous Solutions of Sodium and Potassium Bicarbonate from 293 to 333 K

NARCIS (Netherlands)

Engel, Dico C.; Versteeg, Geert F.; Swaaij, Wim P.M. van

1996-01-01

An experimental study is presented of the hydrogen solubility in aqueous salt solutions containing sodium and potassium bicarbonate from 293 to 333 K. For this purpose, gas consumption measurements have been performed by determining the ultimate pressure decrease in an intensively stirred, high

The structure of the antimicrobial active center of lactoferricin B bound to sodium dodecyl sulfate micelles.

Science.gov (United States)

Schibli, D J; Hwang, P M; Vogel, H J

1999-03-12

Lactoferricin B (LfcinB) is a 25-residue antimicrobial peptide released from bovine lactoferrin upon pepsin digestion. The antimicrobial center of LfcinB consists of six residues (RRWQWR-NH2), and it possesses similar bactericidal activity to LfcinB. The structure of the six-residue peptide bound to sodium dodecyl sulfate (SDS) micelles has been determined by NMR spectroscopy and molecular dynamics refinement. The peptide adopts a well defined amphipathic structure when bound to SDS micelles with the Trp sidechains separated from the Arg residues. Additional evidence demonstrates that the peptide is oriented in the micelle such that the Trp residues are more deeply buried in the micelle than the Arg and Gln residues.

Regeneration of sulfated metal oxides and carbonates

Science.gov (United States)

Hubble, Bill R.; Siegel, Stanley; Cunningham, Paul T.

1978-03-28

Alkali metal or alkaline earth metal carbonates such as calcium carbonate and magnesium carbonate found in dolomite or limestone are employed for removal of sulfur dioxide from combustion exhaust gases. The sulfated carbonates are regenerated to oxides through use of a solid-solid reaction, particularly calcium sulfide with calcium sulfate to form calcium oxide and sulfur dioxide gas. The regeneration is performed by contacting the sulfated material with a reductant gas such as hydrogen within an inert diluent to produce calcium sulfide in mixture with the sulfate under process conditions selected to permit the sulfide-sulfate, solid-state reaction to occur.

The effectiveness of sodium hydroxide (NaOH) and sodium carbonate (Na2CO3) on the impurities removal of saturated salt solution

Science.gov (United States)

Pujiastuti, C.; Ngatilah, Y.; Sumada, K.; Muljani, S.

2018-01-01

Increasing the quality of salt can be done through various methods such as washing (hydro-extraction), re-crystallization, ion exchange methods and others. In the process of salt quality improvement by re-crystallization method where salt product diluted with water to form saturated solution and re-crystallized through heating process. The quality of the salt produced is influenced by the quality of the dissolved salt and the crystallization mechanism applied. In this research is proposed a concept that before the saturated salt solution is recrystallized added a chemical for removal of the impurities such as magnesium ion (Mg), calcium (Ca), potassium (K) and sulfate (SO4) is contained in a saturated salt solution. The chemical reagents that used are sodium hydroxide (NaOH) 2 N and sodium carbonate (Na2CO3) 2 N. This research aims to study effectiveness of sodium hydroxide and sodium carbonate on the impurities removal of magnesium (Mg), calcium (Ca), potassium (K) and sulfate (SO4). The results showed that the addition of sodium hydroxide solution can be decreased the impurity ions of magnesium (Mg) 95.2%, calcium ion (Ca) 45%, while the addition of sodium carbonate solution can decreased magnesium ion (Mg) 66.67% and calcium ion (Ca) 77.5%, but both types of materials are not degradable sulfate ions (SO4). The sodium hydroxide solution more effective to decrease magnesium ion than sodium carbonate solution, and the sodium carbonate solution more effective to decrease calcium ion than sodium hydroxide solution.

Use of sulfate reducing cell suspension bioreactors for the treatment of SO2 rich flue gases

NARCIS (Netherlands)

Lens, P.N.L.; Gastesi, R.; Lettinga, G.

2003-01-01

This paper describes a novel bioscrubber concept for biological flue gas desulfurization, based on the recycling of a cell suspension of sulfite/sulfate reducing bacteria between a scrubber and a sulfite/sulfate reducing hydrogen fed bioreactor. Hydrogen metabolism in sulfite/sulfate reducing cell

A comparison study between sodium dodecyl sulfate and sodium dodecyl sulfonate with respect to the thermodynamic properties, micellization, and interaction with poly(ethylene glycol) in aqueous solutions

International Nuclear Information System (INIS)

Sadeghi, Rahmat; Shahabi, Somayyeh

2011-01-01

Graphical abstract: Apparent molar volume against molality: o, ·, and Δ, respectively in water, (1 and 4) wt% PEG solution at 293.15 K; x, Δ, and lozenge, respectively in water, (1 and 4) wt% PEG solution at 313.15 K. Research highlights: → C 12 H 25 SO 3 Na(SDSn) was seen to interact with PEG more weakly than C 12 H 25 SO 4 Na(SDS). → The constraints on molecular mobility of SDS micelles are larger than those of SDSn. → Entropy change on micellization for SDSn is larger than those for SDS. → Micelle formation of SDS is less endothermic and more spontaneous than that of SDSn. → Micelles of SDS have smaller aggregation number than that of SDSn. - Abstract: The density, sound velocity, and conductivity measurements were performed on aqueous solutions of sodium dodecyl sulfate (C 12 H 25 SO 4 Na) or sodium dodecyl sulfonate (C 12 H 25 SO 3 Na) in the absence and presence of poly(ethylene glycol) (PEG) at different temperatures. Changes in the apparent molar volumes and isentropic compressibilities upon micellization were derived using a pseudophase-transition approach and the infinite dilution apparent molar properties of the monomer and micellar form of C 12 H 25 SO 4 Na and C 12 H 25 SO 3 Na were determined. Variations of the critical micelle concentrations (CMCs) of both surfactants in the solutions investigated with temperature were obtained from which thermodynamic parameters of micellization were estimated. It was found that at low temperature the micelle formation process is endothermic and therefore, this process must be entropically driven. However, upon increasing the temperature, the enthalpic factor becomes more significant and, at temperatures higher than 303.15 K the micellization is enthalpy driven. The interactions between C 12 H 25 SO 4 Na/C 12 H 25 SO 3 Na and PEG were studied and it was found that sodium alkyl sulfonates were seen to interact more weakly than their sulfate analogues.

Intracrystalline site preference of hydrogen isotopes in the water of crystallization of copper sulfate pentahydrate

International Nuclear Information System (INIS)

Kita, I.; Matsuo, S.

1981-01-01

Difference in the isotopic partition at different sites of the water of crystallization of CuSO 4 .5H 2 O (the site preference) was estimated for the hydrogen isotopes. Fractional dehydration of CuSO 4 .5H 2 O under vacuum at 0 and 25 0 C was used to determine the isotopic ratio, the amount of dehydrated water, and the rate process of dehydration. The following results were obtained. (1) Two maxima occur in the isotopic ratio in the dehydration range, F < 0.8. (2) The dehydration occurs by the three sequential zeroth-order rate processes which have different rate constants for dehydration. The three different rate constants may be explained by the combination of the rate constants of dehydration of the water molecules dehydrated. The estimation of the difference in hydrogen isotope distribution for different sites, i.e., four of the five water molecules in the coordination sphere of copper ion (site A) and one bonded to the sulfate ion through hydrogen bonding (site B) was made. The site preference of hydrogen isotopes (delta D,%) was concluded to be -3.20 +- 0.52 for site A and +2.26 +- 2.09 for site B, where the delta D value was referred to the isotopic ratio of the mother liquor from which the crystal was formed

Intracrystalline site preference of hydrogen isotopes in the water of crystallization of copper sulfate pentahydrate

Energy Technology Data Exchange (ETDEWEB)

Kita, I.; Matsuo, S.

1981-04-02

Difference in the isotopic partition at different sites of the water of crystallization of CuSO/sub 4/.5H/sub 2/O (the site preference) was estimated for the hydrogen isotopes. Fractional dehydration of CuSO/sub 4/.5H/sub 2/O under vacuum at 0 and 25/sup 0/C was used to determine the isotopic ratio, the amount of dehydrated water, and the rate process of dehydration. The following results were obtained. (1) Two maxima occur in the isotopic ratio in the dehydration range, F < 0.8. (2) The dehydration occurs by the three sequential zeroth-order rate processes which have different rate constants for dehydration. The three different rate constants may be explained by the combination of the rate constants of dehydration of the water molecules dehydrated. The estimation of the difference in hydrogen isotope distribution for different sites, i.e., four of the five water molecules in the coordination sphere of copper ion (site A) and one bonded to the sulfate ion through hydrogen bonding (site B) was made. The site preference of hydrogen isotopes (delta D,%) was concluded to be -3.20 +- 0.52 for site A and +2.26 +- 2.09 for site B, where the delta D value was referred to the isotopic ratio of the mother liquor from which the crystal was formed.

The removal of Tartrazine dye by modified Alumina with sodium dodecyl sulfate from aqueous solutions: equilibrium and thermodynamic studies

Directory of Open Access Journals (Sweden)

A. Parchebaf Jadid

2017-11-01

Full Text Available Edible colors are materials which in the case of adding to food and drinks cause transferring color to them. Most of these colors are not acceptable in terms of applying in human food and underlies various diseases like gastrointestinal disorders, renal, liver and blood toxicity. The goal of this study was investigating the efficiency of improved alumina by sodium dodecyl sulfate (SDS in eliminating Tartrazine from aqueous environments. In this research, the impact of effective parameters such as initial concentration of Tartrazine, time, pH, alumina dose and SDS value were studied in order to approach an optimal condition for eliminating the color. Also, absorption behavior was evaluated by Freundlich and Langmuir isotherms. The highest efficiency of Tartrazine elimination in the solution resulted in optimal pH of 2, the amount of adsorbent 1.5 g/L, 16 min duration and value 0.04 SDS g/l which was obtained for dye concentration 5 mg/L about 94.13%. Also, results suggested that Tartrazine absorption follows Langmuir isotherm (R2 = 0.9867. Obtained results from thermodynamic studies such as Gibbs free energy (-5.728 Kj/mol and enthalpy (-85.86 Kj/mol and entropy (-271.102 J/mol.K also suggested that the absorption process was exothermic. The results of this research suggested that improved alumina by sodium dodecyl sulfate had a relative good capability in Tartrazine elimination from aqueous environments. Thus

Evaluation of toxicity reduction of sodium dodecyl sulfate submitted to electron beam radiation

Science.gov (United States)

Romanelli, M. F.; Moraes, M. C. F.; Villavicencio, A. L. C. H.; Borrely, S. I.

2004-09-01

Surfactants, as detergent active substances, are an important source of pollution causing biological adverse effects to aquatic organisms. Several data have been showing ecological disturbance due to the high concentration of surfactants on receiving waters and on wastewater treatment plants. Ionizing radiation has been proved as an effective technology to decompose organic substances and few papers have included ecotoxicological aspects. This paper shows the reduction of acute toxicity of a specific surfactant, sodium dodecyl sulfate (SDS), when diluted in distilled water and submitted to electron beam radiation. The study included two test-organisms, the marine bacteria Vibrio fischeri and the crustacean Daphnia similis. Radiation processing resulted in an important acute toxicity removal for both assays, which can be summarized between 70% and 96%, using 3.0, 6.0, 9.0 and 12.0 kGy as radiation doses. Nevertheless, lower doses demonstrated better effect than 9.0 and 12.0 kGy and the bacterium assay was more sensitive to SDS than crustacean assay.

Effect of controlled deactivation on the thermochemical characteristics of hydrogen adsorption on skeletal nickel from sodium hydroxide-water solutions

Science.gov (United States)

Prozorov, D. A.; Lukin, M. V.; Ulitin, M. V.

2013-04-01

Differential heats of adsorption in a wide range of surface coverage and maximum amounts of adsorbed hydrogen are determined by adsorption calorimetry on partially deactivated skeletal nickel from aqueous solutions of sodium hydroxide. The effect of the composition of solutions on the values of limiting adsorption and adsorption equilibria of individual forms of hydrogen is shown.

Tin and tin-titanium as catalyst components for reversible hydrogen storage of sodium aluminium hydride

Energy Technology Data Exchange (ETDEWEB)

Qi Jia Fu; Shik Chi Tsang [University of Reading, Reading (United Kingdom). Surface and Catalysis Research Centre, School of Chemistry

2006-10-15

This paper is concerned with the effects of adding tin and/or titanium dopant to sodium aluminium hydride for both dehydrogenation and re-hydrogenation reactions during their reversible storage of molecular hydrogen. Temperature programmed decomposition (TPD) measurements show that the dehydrogenation kinetics of NaAlH{sub 4} are significantly enhanced upon doping the material with 2 mol% of tributyltin hydride, Sn(Bu)3H but the tin catalyst dopant is shown to be inferior than titanium. On the other hand, in this preliminary work, a significant synergetic catalytic effect is clearly revealed in material co-doped with both titanium and tin catalysts which shows the highest reversible rates of dehydrogenation and re-hydrogenation (after their hydrogen depletion). The re-hydrogenation rates of depleted Sn/Ti/NaAlH{sub 4} evaluated at both 9.5 and 140 bars hydrogen are also found to be favourable compared to the Ti/NaAlH{sub 4}, which clearly suggest the importance of the catalyst choice. Basing on these results some mechanistic insights for the catalytic reversible dehydrogenation and re-hydrogenation processes of Sn/Ti/NaAlH{sub 4} are therefore made. 31 refs., 8 figs., 2 tabs.

Mixed sodium nickel-manganese sulfates: Crystal structure relationships between hydrates and anhydrous salts

Energy Technology Data Exchange (ETDEWEB)

Marinova, Delyana M.; Zhecheva, Ekaterina N.; Kukeva, Rositsa R.; Markov, Pavel V. [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Nihtianova, Diana D. [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Institute of Mineralogy and Crystallography, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Stoyanova, Radostina K., E-mail: radstoy@svr.igic.bas.bg [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)

2017-06-15

The present contribution provides new structural and spectroscopic data on the formation of solid solutions between hydrated and dehydrated sulfate salts of sodium-nickel and sodium-manganese in a whole concentration range: Na{sub 2}Ni{sub 1−x}Mn{sub x}(SO{sub 4}){sub 2}·yH{sub 2}O, 0≤ x≤1.0. Using powder XRD, electron paramagnetic resonance spectroscopy (EPR), IR and Raman spectroscopy it has been found that double sodium-nickel and sodium-manganese salts form solid solutions Na{sub 2}Ni{sub 1−x}Mn{sub x}(SO{sub 4}){sub 2}·4H{sub 2}O with a blödite-type of structure within a broad concentration range of 0≤x≤0.49, while the manganese rich compositions Na{sub 2}Ni{sub 1−x}Mn{sub x}(SO{sub 4}){sub 2}·2H{sub 2}O (0.97≤x≤1.0) crystallize in the kröhnkite-type of structure. The Ni-based blödites Na{sub 2}Ni{sub 1−x}Mn{sub x}(SO{sub 4}){sub 2}·4H{sub 2}O dehydrate between 140 and 260 °C into anhydrous salts Na{sub 2}Ni{sub 1−x}Mn{sub x}(SO{sub 4}){sub 2}, 0≤ x≤0.44, with a structure where Ni{sub 1−x}Mn{sub x}O{sub 6} octahedra are bridged into pairs by edge- and corner sharing SO{sub 4}{sup 2−} groups. Both TEM and EPR methods show that the Ni{sup 2+} and Mn{sup 2+} ions are homogenously distributed over three crystallographic positions of the large monoclinic cell. The dehydration of the kröhnkite phase Na{sub 2}Ni{sub 1−x}Mn{sub x}(SO{sub 4}){sub 2}·2H{sub 2}O yields the alluaudite phase Na{sub 2+δ}Mn{sub 2-δ/2}(SO{sub 4}){sub 3}, where the Na-to-Mn ratio decreases and all Ni{sup 2+} dopants are released from the structure. The process of the dehydration is discussed in terms of structural aspects taking into account the distortion degree of the Ni,MnO{sub 6} and SO{sub 4} polyhedra. - Graphical abstract: Thermal dehydration of the blödite phase Na{sub 2}Ni{sub 1−x}Mn{sub x}(SO{sub 4}){sub 2}·4H{sub 2}O (0≤ x≤0.49) yields nickel-manganese sulfates Na{sub 2}Ni{sub 1−x}Mn{sub x}(SO{sub 4}){sub 2} (0≤ x≤0.44) with

Synthesis of [2,4-3H] 17β-dihydroequilin sulfate

International Nuclear Information System (INIS)

Bhavnani, B.R.

1994-01-01

[2,4- 3 H] 17β-dihydroequilin-3-sulfate ammonium salt suitable for in vivo pharmacokinetic studies was synthesized from [2,4- 3 H] equilin. Sulfation of [2,4- 3 H] equilin with pyridine-chlorosulfonic acid mixture gave in high yields [2,4- 3 H] equilin sulfate, which was then reduced with sodium borohydride to yield [2,4- 3 H] 17β-dihydroequilin sulfate. The reduction was sterospecific and no 17α-reduced products were formed. (author)

Modeling of Sulfate Double-Salt in Nuclear Wastes

International Nuclear Information System (INIS)

Toghiani, B.; Lindner, J.S.; Weber, C.F.; Hunt, R.D.

2000-01-01

The Environmental Simulation Program (ESP) continues to adequately predict the solubility of most key chemical systems in the Hanford tank waste. For example, the ESP predictions were in fair agreement with the solubility experiments for the fluoride-phosphate system, although ESP probably underestimates the aqueous amounts. Due to the importance of this system in the formation of pipeline plugs, additional experiments have been made at elevated temperatures, and improvements to the ESP database will be made. ESP encountered problems with sulfate systems because the Public database for ESP does not include anhydrous sodium sulfate in mixed solutions below 32.4 C. This limitation leads to convergence problems and to spurious predictions of solubility near the transition point with sodium sulfate decahydrate when other salts such as sodium nitrate are present. However, ESP was able to make reasonable solubility predictions with a corrected database, demonstrating the need to validate and document the various databases that can be used by ESP. Even though ESP does not include the sulfate-nitrate double salt, this omission does not appear to be a major problem. The solubility predictions with and without the sulfate-nitrate double salt are comparable. In sharp contrast, the sulfate-fluoride double salt is included, but ESP still underestimates solubility in some cases. This problem can misrepresent the ionic strength of the solution, which is an important factor in the formation of pipeline plugs. Solubility tests on the sulfate-fluoride system are planned to provide additional data at higher temperatures and in caustic solutions. These results will be used to improve the range and accuracy of ESP predictions. ESP will continue to provide important predictions for waste processing operations while being evaluated and improved. For example, ESP will be used to determine the amount of water for the saltcake dissolution efforts at Hanford. When ESP underestimates the

Thermometric titration of cadmium with sodium diethyldithiocarbamate, with oxidation by hydrogen peroxide as indicator reaction.

Science.gov (United States)

Hattori, T; Yoshida, H

1987-08-01

A new method of end-point indication is described for thermometric titration of cadmium with sodium diethyldithiocarbamate (DDTC). It is based on the redox reaction between hydrogen peroxide added to the system before titration, and the first excess of DDTC. Amounts of cadmium in the range 10-50 mumoles are titrated within 1% error.

Alkaline sodium borohydride gel as a hydrogen source for PEMFC or an energy carrier for NaBH{sub 4}-air battery

Energy Technology Data Exchange (ETDEWEB)

Liu, B.H. [Department of Materials and Engineering, Zhejiang University (China); Li, Z.P.; Chen, L.L. [Department of Chemical and Biochemical Engineering, Zhejiang University, Hangzhou 310027 (China)

2008-05-15

In this preliminary study, we tried to use sodium polyacrylate as the super absorbent polymer to form alkaline NaBH{sub 4} gel and explored its possibilities for borohydride hydrolysis and borohydride electro-oxidation. It was found that the absorption capacity of sodium polyacrylate decreased with increasing NaBH{sub 4} concentration. The formed gel was rather stable in the sealed vessel but tended to slowly decompose in open air. Hydrogen generation from the gel was carried out using CoCl{sub 2} catalyst precursor solutions. Hydrogen generation rate from the alkaline NaBH{sub 4} gel was found to be higher and impurities in hydrogen were less than that from the alkaline NaBH{sub 4} solution. The NaBH{sub 4} gel also successfully powered a NaBH{sub 4}-air battery. (author)

Measurement of chemical leaching potential of sulfate from landfill disposed sulfate containing wastes.

Science.gov (United States)

Sun, Wenjie; Barlaz, Morton A

2015-02-01

A number of sulfate-containing wastes are disposed in municipal solid wastes (MSW) landfills including residues from coal, wood, and MSW combustion, and construction and demolition (C&D) waste. Under anaerobic conditions that dominate landfills, the sulfate can be reduced to hydrogen sulfide which is problematic for several reasons including its low odor threshold, toxicity, and corrosive nature. The overall objective of this study was to evaluate existing protocols for the quantification of total leachable sulfate from solid samples and to compare their effectiveness and efficiency with a new protocol described in this study. Methods compared include two existing acid extraction protocols commonly used in the U.S., a pH neutral protocol that requires multiple changes of the leaching solution, and a new acid extraction method. The new acid extraction method was shown to be simple and effective to measure the leaching potential of sulfate from a range of landfill disposed sulfate-containing wastes. However, the acid extraction methods do not distinguish between sulfate and other forms of sulfur and are thus most useful when sulfate is the only form of sulfur present. Copyright © 2014 Elsevier Ltd. All rights reserved.

Significant role of organic sulfur in supporting sedimentary sulfate reduction in low-sulfate environments

Science.gov (United States)

Fakhraee, Mojtaba; Li, Jiying; Katsev, Sergei

2017-09-01

Dissimilatory sulfate reduction (DSR) is a major carbon mineralization pathway in aquatic sediments, soils, and groundwater, which regulates the production of hydrogen sulfide and the mobilization rates of biologically important elements such as phosphorus and mercury. It has been widely assumed that water-column sulfate is the main sulfur source to fuel this reaction in sediments. While this assumption may be justified in high-sulfate environments such as modern seawater, we argue that in low-sulfate environments mineralization of organic sulfur compounds can be an important source of sulfate. Using a reaction-transport model, we investigate the production of sulfate from sulfur-containing organic matter for a range of environments. The results show that in low sulfate environments (50%) of sulfate reduction. In well-oxygenated systems, porewater sulfate profiles often exhibit sub-interface peaks so that sulfate fluxes are directed out of the sediment. Our measurements in Lake Superior, the world's largest lake, corroborate this conclusion: offshore sediments act as sources rather than sinks of sulfate for the water column, and sediment DSR is supported entirely by the in-sediment production of sulfate. Sulfate reduction rates are correlated to the depth of oxygen penetration and strongly regulated by the supply of reactive organic matter; rate co-regulation by sulfate availability becomes appreciable below 500 μM level. The results indicate the need to consider the mineralization of organic sulfur in the biogeochemical cycling in low-sulfate environments, including several of the world's largest freshwater bodies, deep subsurface, and possibly the sulfate-poor oceans of the Early Earth.

Hydrogen meter prooftesting

International Nuclear Information System (INIS)

McCown, J.J.; Mettler, G.W.

1976-04-01

Two diffusion type hydrogen meters have been tested on the Prototype Applications Loop (PAL). The ANL designed unit was used to monitor hydrogen in sodium during FFTF startup and over a wide range of hydrogen concentrations resulting from chemical additions to the sodium and cover gas. A commercially available meter was added and its performance compared with the ANL unit. Details of the test work are described

Hydrogen substituted graphdiyne as carbon-rich flexible electrode for lithium and sodium ion batteries.

Science.gov (United States)

He, Jianjiang; Wang, Ning; Cui, Zili; Du, Huiping; Fu, Lin; Huang, Changshui; Yang, Ze; Shen, Xiangyan; Yi, Yuanping; Tu, Zeyi; Li, Yuliang

2017-10-27

Organic electrodes are potential alternatives to current inorganic electrode materials for lithium ion and sodium ion batteries powering portable and wearable electronics, in terms of their mechanical flexibility, function tunability and low cost. However, the low capacity, poor rate performance and rapid capacity degradation impede their practical application. Here, we concentrate on the molecular design for improved conductivity and capacity, and favorable bulk ion transport. Through an in situ cross-coupling reaction of triethynylbenzene on copper foil, the carbon-rich frame hydrogen substituted graphdiyne film is fabricated. The organic film can act as free-standing flexible electrode for both lithium ion and sodium ion batteries, and large reversible capacities of 1050 mAh g -1 for lithium ion batteries and 650 mAh g -1 for sodium ion batteries are achieved. The electrode also shows a superior rate and cycle performances owing to the extended π-conjugated system, and the hierarchical pore bulk with large surface area.

Sodium lauryl sulfate - a biocide for controlling acidity development in bulk commercially formed solid elemental sulfur

Energy Technology Data Exchange (ETDEWEB)

Hyne, J. B. [Calgary Univ., AB (Canada). Dept. of Biological Sciences

1996-04-01

Acidification of bulk elemental sulfur caused by Thiobacillus species which consume elemental sulfur by converting it into oxidized sulfur forms, was studied. Contributory factors, such as length of time in transit or in storage, warm temperatures, the presence of air and moisture, particle size and form of sulfur, and the presence of sources of carbon, nitrogen and phosphorus nutrients, were reviewed. Laboratory experiments with adding sodium lauryl sulfate (SLS), a known biocide, to sulfur inoculated with Thiobacillus, proved to be an efficient method for controlling acidity development. At the concentration required for effectiveness SLS did not interfere with purity specifications, had negligible effect on moisture, and appeared to be compatible with current dust suppression application practices. 2 tabs., 3 figs.

Influence of Sodium Lauryl Sulfate and Tween 80 on Carbamazepine–Nicotinamide Cocrystal Solubility and Dissolution Behaviour

Science.gov (United States)

Li, Mingzhong; Qiao, Ning; Wang, Ke

2013-01-01

The influence of the surfactants of sodium lauryl sulfate (SLS) and Tween 80 on carbamazepine–nicotinamide (CBZ–NIC) cocrystal solubility and dissolution behaviour has been studied in this work. The solubility of the CBZ–NIC cocrystal was determined by measuring the eutectic concentrations of the drug and the coformer. Evolution of the intrinsic dissolution rate (IDR) of the CBZ–NIC cocrystal was monitored by the UV imaging dissolution system during dissolution. Experimental results indicated that SLS and Tween 80 had little influence upon the solubility of the CBZ–NIC cocrystal but they had totally opposite effects on the IDR of the CBZ–NIC cocrystal during dissolution. SLS significantly increased the IDR of the CBZ–NIC cocrystal while Tween 80 decreased its IDR. PMID:24300560

Influence of Sodium Lauryl Sulfate and Tween 80 on Carbamazepine–Nicotinamide Cocrystal Solubility and Dissolution Behaviour

Directory of Open Access Journals (Sweden)

Ke Wang

2013-10-01

Full Text Available The influence of the surfactants of sodium lauryl sulfate (SLS and Tween 80 on carbamazepine–nicotinamide (CBZ–NIC cocrystal solubility and dissolution behaviour has been studied in this work. The solubility of the CBZ–NIC cocrystal was determined by measuring the eutectic concentrations of the drug and the coformer. Evolution of the intrinsic dissolution rate (IDR of the CBZ–NIC cocrystal was monitored by the UV imaging dissolution system during dissolution. Experimental results indicated that SLS and Tween 80 had little influence upon the solubility of the CBZ–NIC cocrystal but they had totally opposite effects on the IDR of the CBZ–NIC cocrystal during dissolution. SLS significantly increased the IDR of the CBZ–NIC cocrystal while Tween 80 decreased its IDR.

Influence of sodium lauryl sulfate and tween 80 on carbamazepine-nicotinamide cocrystal solubility and dissolution behaviour.

Science.gov (United States)

Li, Mingzhong; Qiao, Ning; Wang, Ke

2013-10-11

The influence of the surfactants of sodium lauryl sulfate (SLS) and Tween 80 on carbamazepine-nicotinamide (CBZ-NIC) cocrystal solubility and dissolution behaviour has been studied in this work. The solubility of the CBZ-NIC cocrystal was determined by measuring the eutectic concentrations of the drug and the coformer. Evolution of the intrinsic dissolution rate (IDR) of the CBZ-NIC cocrystal was monitored by the UV imaging dissolution system during dissolution. Experimental results indicated that SLS and Tween 80 had little influence upon the solubility of the CBZ-NIC cocrystal but they had totally opposite effects on the IDR of the CBZ-NIC cocrystal during dissolution. SLS significantly increased the IDR of the CBZ-NIC cocrystal while Tween 80 decreased its IDR.

Evaluation of changes in serum chemistry in association with feed withdrawal or high dose oral gavage with Dextran Sodium Sulfate (DSS) induced gut leakage in broiler chickens

Science.gov (United States)

Dextran sodium sulfate (DSS) has been shown to be effective at inducing enteric inflammation in broiler chickens, resulting in increased leakage of orally administered fluorescein isothiocyanate dextran to circulation. In a previous study, two doses of DSS (0.45g/dose) administered as oral gavage re...

Mixed layers of sodium caseinate + dextran sulfate: influence of order of addition to oil-water interface.

Science.gov (United States)

Jourdain, Laureline S; Schmitt, Christophe; Leser, Martin E; Murray, Brent S; Dickinson, Eric

2009-09-01

We report on the interfacial properties of electrostatic complexes of protein (sodium caseinate) with a highly sulfated polysaccharide (dextran sulfate). Two routes were investigated for preparation of adsorbed layers at the n-tetradecane-water interface at pH = 6. Bilayers were made by the layer-by-layer deposition technique whereby polysaccharide was added to a previously established protein-stabilized interface. Mixed layers were made by the conventional one-step method in which soluble protein-polysaccharide complexes were adsorbed directly at the interface. Protein + polysaccharide systems gave a slower decay of interfacial tension and stronger dilatational viscoelastic properties than the protein alone, but there was no significant difference in dilatational properties between mixed layers and bilayers. Conversely, shear rheology experiments exhibited significant differences between the two kinds of interfacial layers, with the mixed system giving much stronger interfacial films than the bilayer system, i.e., shear viscosities and moduli at least an order of magnitude higher. The film shear viscoelasticity was further enhanced by acidification of the biopolymer mixture to pH = 2 prior to interface formation. Taken together, these measurements provide insight into the origin of previously reported differences in stability properties of oil-in-water emulsions made by the bilayer and mixed layer approaches. Addition of a proteolytic enzyme (trypsin) to both types of interfaces led to a significant increase in the elastic modulus of the film, suggesting that the enzyme was adsorbed at the interface via complexation with dextran sulfate. Overall, this study has confirmed the potential of shear rheology as a highly sensitive probe of associative electrostatic interactions and interfacial structure in mixed biopolymer layers.

Sodium/hydrogen-exchanger inhibition during cardioplegic arrest and cardiopulmonary bypass: an experimental study.

Science.gov (United States)

Cox, Charles S; Sauer, Henning; Allen, Steven J; Buja, L Maximilian; Laine, Glen A

2002-05-01

We sought to determine whether pretreatment with a sodium/hydrogen-exchange inhibitor (EMD 96 785) improves myocardial performance and reduces myocardial edema after cardioplegic arrest and cardiopulmonary bypass. Anesthetized dogs (n = 13) were instrumented with vascular catheters, myocardial ultrasonic crystals, and left ventricular micromanometers to measure preload recruitable stroke work, maximum rate of pressure rise (positive and negative), and left ventricular end-diastolic volume and pressure. Cardiac output was measured by means of thermodilution. Myocardial tissue water content was determined from sequential biopsy. After baseline measurements, hypothermic (28 degrees C) cardiopulmonary bypass was initiated. Cardioplegic arrest (4 degrees C Bretschneider crystalloid cardioplegic solution) was maintained for 2 hours, followed by reperfusion-rewarming and separation from cardiopulmonary bypass. Preload recruitable stroke work and myocardial tissue water content were measured at 30, 60, and 120 minutes after bypass. EMD 96 785 (3 mg/kg) was given 15 minutes before bypass, and 2 micromol was given in the cardioplegic solution. Control animals received the same volume of saline vehicle. Arterial-coronary sinus lactate difference was similar in both animals receiving EMD 96 785 and control animals, suggesting equivalent myocardial ischemia in each group. Myocardial tissue water content increased from baseline in both animals receiving EMD 96 785 and control animals with cardiopulmonary bypass and cardioplegic arrest but was statistically lower in animals receiving EMD 96 785 compared with control animals (range, 1.0%-1.5% lower in animals receiving EMD 96 785). Preload recruitable stroke work decreased from baseline (97 +/- 2 mm Hg) at 30 (59 +/- 6 mm Hg) and 60 (72 +/- 9 mm Hg) minutes after cardiopulmonary bypass and cardioplegic arrest in control animals; preload recruitable stroke work did not decrease from baseline (98 +/- 2 mm Hg) in animals receiving

Oral fluoride levels 1 h after use of a sodium fluoride rinse: effect of sodium lauryl sulfate.

Science.gov (United States)

Vogel, Gerald L; Schumacher, Gary E; Chow, Laurence C; Tenuta, Livia M A

2015-01-01

Increasing the concentration of free fluoride in oral fluids is an important goal in the use of topical fluoride agents. Although sodium lauryl sulfate (SLS) is a common dentifrice ingredient, the influence of this ion on plaque fluid and salivary fluid fluoride has not been examined. The purpose of this study was to investigate the effect of SLS on these parameters and to examine the effect of this ion on total (or whole) plaque fluoride, an important source of plaque fluid fluoride after a sufficient interval following fluoride administration, and on total salivary fluoride, a parameter often used as a surrogate measure of salivary fluid fluoride. Ten subjects accumulated plaque for 48 h before rinsing with a 12 mmol/l NaF (228 µg/g F) rinse containing or not containing 0.5% (w/w) SLS. SLS had no statistically significant effect on total plaque and total saliva fluoride but significantly increased salivary fluid and plaque fluid fluoride (by 147 and 205%, respectively). These results suggest that the nonfluoride components of topical agents can be manipulated to improve the fluoride release characteristics from oral fluoride reservoirs and that statistically significant change may be observed in plaque fluid and salivary fluid fluoride concentrations that may not be observed in total plaque and total saliva fluoride concentrations.

Chitosan-sodium lauryl sulfate nanoparticles as a carrier system for the in vivo delivery of oral insulin.

Science.gov (United States)

Elsayed, Amani; Al-Remawi, Mayyas; Qinna, Nidal; Farouk, Asim; Al-Sou'od, Khaldoun A; Badwan, Adnan A

2011-09-01

The present work explores the possibility of formulating an oral insulin delivery system using nanoparticulate complexes made from the interaction between biodegradable, natural polymer called chitosan and anionic surfactant called sodium lauryl sulfate (SLS). The interaction between chitosan and SLS was confirmed by Fourier transform infrared spectroscopy. The nanoparticles were prepared by simple gelation method under aqueous-based conditions. The nanoparticles were stable in simulated gastric fluids and could protect the encapsulated insulin from the GIT enzymes. Additionally, the in vivo results clearly indicated that the insulin-loaded nanoparticles could effectively reduce the blood glucose level in a diabetic rat model. However, additional formulation modifications are required to improve insulin oral bioavailability.

Measuring the enthalpies of interaction between glycine, L-cysteine, glycylglycine, and sodium dodecyl sulfate in aqueous solutions

Science.gov (United States)

Badelin, V. G.; Mezhevoi, I. N.; Tyunina, E. Yu.

2017-03-01

Calorimetric measurements of enthalpies of solution Δsol H m for glycine, L-cysteine, and glycylglycine in aqueous solutions of sodium dodecyl sulfate (SDS) with concentrations of up to 0.05 mol kg-1 are made. Standard enthalpy of solution Δsol H 0 and enthalpy of transfer Δtr H 0 of the dipeptide from water into mixed solvent are calculated. The calculated enthalpy coefficients of paired interactions of amino acids and dipeptide with SDS prove to be positive. Hydrophobic interactions between the biomolecules and SDS are found to have a major impact on the enthalpies of interaction in the three-component systems under study, within the indicated range of concentrations.

Voltammetric Determination of Ivabradine Hydrochloride Using Multiwalled Carbon Nanotubes Modified Electrode in Presence of Sodium Dodecyl Sulfate.

Science.gov (United States)

Attia, Ali Kamal; Abo-Talib, Nisreen Farouk; Tammam, Marwa Hosny

2017-04-01

Purpose: A new sensitive sensor was fabricated for the determination of ivabradine hydrochloride (IH) based on modification with multiwalled carbon nanotubes using sodium dodecyl sulfate as micellar medium to increase the sensitivity. Methods: The electrochemical behavior of IH was studied in Britton-Robinson buffer (pH: 2.0-11.0) using cyclic and differential pulse voltammetry. Results: The voltammetric response was linear over the range of 3.984 x 10 -6 -3.475 x 10 -5 mol L -1 . The limits of detection and quantification were found to be 5.160 x 10 -7 and 1.720 x 10-6 mol L -1 , respectively. Conclusion: This method is suitable for determination of IH in tablets and plasma.

Sulfation and cation effects on the conformational properties of the glycan backbone of chondroitin sulfate disaccharides.

Science.gov (United States)

Faller, Christina E; Guvench, Olgun

2015-05-21

Chondroitin sulfate (CS) is one of several glycosaminoglycans that are major components of proteoglycans. A linear polymer consisting of repeats of the disaccharide -4GlcAβ1-3GalNAcβ1-, CS undergoes differential sulfation resulting in five unique sulfation patterns. Because of the dimer repeat, the CS glycosidic "backbone" has two distinct sets of conformational degrees of freedom defined by pairs of dihedral angles: (ϕ1, ψ1) about the β1-3 glycosidic linkage and (ϕ2, ψ2) about the β1-4 glycosidic linkage. Differential sulfation and the possibility of cation binding, combined with the conformational flexibility and biological diversity of CS, complicate experimental efforts to understand CS three-dimensional structures at atomic resolution. Therefore, all-atom explicit-solvent molecular dynamics simulations with Adaptive Biasing Force sampling of the CS backbone were applied to obtain high-resolution, high-precision free energies of CS disaccharides as a function of all possible backbone geometries. All 10 disaccharides (β1-3 vs β1-4 linkage × five different sulfation patterns) were studied; additionally, ion effects were investigated by considering each disaccharide in the presence of either neutralizing sodium or calcium cations. GlcAβ1-3GalNAc disaccharides have a single, broad, thermodynamically important free-energy minimum, whereas GalNAcβ1-4GlcA disaccharides have two such minima. Calcium cations but not sodium cations bind to the disaccharides, and binding is primarily to the GlcA -COO(-) moiety as opposed to sulfate groups. This binding alters the glycan backbone thermodynamics in instances where a calcium cation bound to -COO(-) can act to bridge and stabilize an interaction with an adjacent sulfate group, whereas, in the absence of this cation, the proximity of a sulfate group to -COO(-) results in two like charges being both desolvated and placed adjacent to each other and is found to be destabilizing. In addition to providing information

Final report on the safety assessment of sodium sulfite, potassium sulfite, ammonium sulfite, sodium bisulfite, ammonium bisulfite, sodium metabisulfite and potassium metabisulfite.

Science.gov (United States)

Nair, Bindu; Elmore, Amy R

2003-01-01

Sodium Sulfite, Ammonium Sulfite, Sodium Bisulfite, Potassium Bisulfite, Ammonium Bisulfite, Sodium Metabisulfite, and Potassium Metabisulfite are inorganic salts that function as reducing agents in cosmetic formulations. All except Sodium Metabisulfite also function as hair-waving/straightening agents. In addition, Sodium Sulfite, Potassium Sulfite, Sodium Bisulfite, and Sodium Metabisulfite function as antioxidants. Although Ammonium Sulfite is not in current use, the others are widely used in hair care products. Sulfites that enter mammals via ingestion, inhalation, or injection are metabolized by sulfite oxidase to sulfate. In oral-dose animal toxicity studies, hyperplastic changes in the gastric mucosa were the most common findings at high doses. Ammonium Sulfite aerosol had an acute LC(50) of >400 mg/m(3) in guinea pigs. A single exposure to low concentrations of a Sodium Sulfite fine aerosol produced dose-related changes in the lung capacity parameters of guinea pigs. A 3-day exposure of rats to a Sodium Sulfite fine aerosol produced mild pulmonary edema and irritation of the tracheal epithelium. Severe epithelial changes were observed in dogs exposed for 290 days to 1 mg/m(3) of a Sodium Metabisulfite fine aerosol. These fine aerosols contained fine respirable particle sizes that are not found in cosmetic aerosols or pump sprays. None of the cosmetic product types, however, in which these ingredients are used are aerosolized. Sodium Bisulfite (tested at 38%) and Sodium Metabisulfite (undiluted) were not irritants to rabbits following occlusive exposures. Sodium Metabisulfite (tested at 50%) was irritating to guinea pigs following repeated exposure. In rats, Sodium Sulfite heptahydrate at large doses (up to 3.3 g/kg) produced fetal toxicity but not teratogenicity. Sodium Bisulfite, Sodium Metabisulfite, and Potassium Metabisulfite were not teratogenic for mice, rats, hamsters, or rabbits at doses up to 160 mg/kg. Generally, Sodium Sulfite, Sodium

A novel, environmentally friendly sodium lauryl ether sulfate-, cocamidopropyl betaine-, cocamide monoethanolamine-containing buffer for MEKC on microfluidic devices.

Science.gov (United States)

Hoeman, Kurt W; Culbertson, Christopher T

2008-12-01

A new buffer has been developed for fast, high-efficiency separations of amino acids by MEKC. This buffer was more environmentally friendly than the most commonly used surfactant-containing buffers for MEKC separations. It used a commercially available dishwashing soap by Seventh Generation (Burlington, VT, USA), which contained three micelle-forming agents. The mixed micelles were composed of sodium lauryl ether sulfate (anionic), cocamidopropyl betaine (zwitterionic), and cocamide monoethanolamine (non-ionic). The optimized buffer contained 5.0% w/w Seventh Generation Free & Clear dishwashing soap, 10 mM sodium borate, and was completely void of organics. The lack of organics and the biodegradability of the surfactant molecules made this buffer more environmentally friendly than typical SDS-containing buffers. This new buffer also had a different selectivity and provided faster separations with higher separation efficiencies than SDS-based buffers. Fast separations of BODIPY FL labeled amino acids yielded peaks with separation efficiencies greater than 100,000 in less than 20 s.

A novel reverse osmosis membrane by ferrous sulfate assisted controlled oxidation of polyamide layer

Science.gov (United States)

Raval, Hiren D.; Raviya, Mayur R.; Gauswami, Maulik V.

2017-11-01

With growing desalination capacity, it is very important to evaluate the performance of thin film composite reverse osmosis (TFC RO) membrane in terms of energy consumption for desalination. There is a trade-off between salt rejection and water-flux of TFC RO membrane. This article presents a novel approach of analyzing the effect of mixture of an oxidizing agent sodium hypochlorite and a reducing agent ferrous sulfate on virgin TFC RO membrane. Experiments were carried out by varying the concentrations of both sodium hypochlorite and ferrous sulfate. The negative charge was induced on the membrane due to the treatment of combination of sodium hypochlorite and ferrous sulfate, thereby resulting in higher rejection of negative ions due to repulsive force. Membrane treated with 1000 mg l-1 sodium hypochlorite and 2000 mg l-1 ferrous sulfate showed the best salt rejection i.e. 96.23%. The characterization was carried out to understand the charge on the membrane surface by Zeta potential, morphology of membrane surface by scanning electron microscope (SEM), surface roughness features by atomic force microscope (AFM) and chemical structural changes by nuclear magnetic resonance (NMR) analysis.

Dietary reference intakes for water, potassium, sodium, chloride, and sulfate

National Research Council Canada - National Science Library

Institute of Medicine (U.S.). Panel on Dietary Reference Intakes for Electrolytes and Water

2005-01-01

... intake to the risk of high blood pressure and hypertension as well as other diseases and the amounts of water from beverages and foods needed to maintain hydration. In addition, since requirements for sulfur can be met by inorganic sulfate in the diets of animals, a review of the role in inorganic sulfur in the form of sulfate is included. The gro...

Liquid-phase chemical hydrogen storage: catalytic hydrogen generation under ambient conditions.

Science.gov (United States)

Jiang, Hai-Long; Singh, Sanjay Kumar; Yan, Jun-Min; Zhang, Xin-Bo; Xu, Qiang

2010-05-25

There is a demand for a sufficient and sustainable energy supply. Hence, the search for applicable hydrogen storage materials is extremely important owing to the diversified merits of hydrogen energy. Lithium and sodium borohydride, ammonia borane, hydrazine, and formic acid have been extensively investigated as promising hydrogen storage materials based on their relatively high hydrogen content. Significant advances, such as hydrogen generation temperatures and reaction kinetics, have been made in the catalytic hydrolysis of aqueous lithium and sodium borohydride and ammonia borane as well as in the catalytic decomposition of hydrous hydrazine and formic acid. In this Minireview we briefly survey the research progresses in catalytic hydrogen generation from these liquid-phase chemical hydrogen storage materials.

Methane production, sulfate reduction and competition for substrates in the sediments of Lake Washington

Energy Technology Data Exchange (ETDEWEB)

Kuivila, K.M.; Murray, J.W.; Devol, A.H. (Univ. of Washington, Seattle (USA)); Novelli, P.C. (Univ. of Colorado, Boulder (USA))

1989-02-01

Rates of methane production (both acetate fermentation and CO{sub 2} reduction) and sulfate reduction were directly measured as a function of depth in the sediments of Lake Washington. Although methanogenesis was the primary mode of anaerobic respiration (63%), the major zone of methane production existed only below the sulfate reduction zone (16 cm). Acetate fermentation accounted for 61 to 85% of the total methane production, which is consistent with other low sulfate environments. The observed spatial separation of methane production and sulfate reduction, which has been reported for marine sediments, is attributed to competition between the methane-producing and sulfate-reducing bacteria for acetate and hydrogen. This hypothesis is supported by the strong correlation between the measured distributions of acetate and hydrogen and the rates of methane produced from these two precursors in Lake Washington sediments. Acetate concentrations increased rapidly (from 10-16 {mu}M to 30-40 {mu}M) once the sulfate concentration decreased below 30 {mu}M and methane production via acetate fermentation began. A similar trend was observed for hydrogen concentrations, which increased from 7 to 22 nM up to 40 to 55 nM, at the onset of methanogenesis from CO{sub 2} and H{sub 2} (sulfate concentrations of 35-40 {mu}M). These results show, for the first time in a freshwater lake, the separation of methane production and sulfate reduction and the corresponding changes in acetate and hydrogen concentrations.

Transport Pathways and Enhancement Mechanisms within Localized and Non-Localized Transport Regions in Skin Treated with Low-Frequency Sonophoresis and Sodium Lauryl Sulfate

OpenAIRE

Polat, Baris E.; Figueroa, Pedro L.; Blankschtein, Daniel; Langer, Robert

2010-01-01

Recent advances in transdermal drug delivery utilizing low-frequency sonophoresis (LFS) and sodium lauryl sulfate (SLS) have revealed that skin permeability enhancement is not homogenous across the skin surface. Instead, highly perturbed skin regions, known as localized transport regions (LTRs), exist. Despite these findings, little research has been conducted to identify intrinsic properties and formation mechanisms of LTRs and the surrounding less-perturbed non-LTRs. By independently analyz...

Sulfate Salts in Gasoline and Ethanol Fuels -- Historical Perspective and Analysis of Available Data

Energy Technology Data Exchange (ETDEWEB)

McCormick, Robert L. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Alleman, Teresa [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Yanowitz, Janet [Ecoengineering, Inc., Sharonville, OH (United States)

2017-09-21

This report reviews the chemistry of sulfate salts dissolved in ethanol and gasoline, potential sources of sulfate salts in ethanol and gasoline, the history of consumer vehicle issues with sulfate salt deposits in the early 2000s, and the corresponding changes to the denatured fuel ethanol specification. Recommendations for future research are provided. During a period of rapid market expansion in 2004-05, issues were reported with vehicles running on E10 provided by certain suppliers in some markets. It was commonly believed that these vehicle problems were caused by sulfate salts precipitating from the fuel. Investigators identified sodium sulfate, and in one case also ammonium sulfate, as the predominate salts found in the engines. Several stakeholders believed the issue was excess sulfate ions in the ethanol portion of the E10, and in 2005 the ASTM specification for ethanol (D4806) was modified to include a 4-part per million (ppm) limit on sulfate ions. While there have been no further reports of consumer vehicle issues, the recently approved increase of ethanol in gasoline from 10 to 15 volume percent has resulted in renewed interest in the sulfate ion concentration in fuel ethanol. This report reviews published data on the solubility of sulfate salts in ethanol. The possible sources of sulfate anions and charge balancing cations (such as sodium) in fuel ethanol and petroleum derived blendstocks are discussed. Examination of historical information on the consumer vehicle issues that occurred in 2004-2005 reveals that a source of sodium or ammonium ions, required for the formation of the observed insoluble salts, was never identified. Recommendations for research to better understand sulfate salt solubility issues in ethanol, hydrocarbon blendstocks, and ethanol-gasoline blends are presented.

In vivo turnover of the basement membrane and other heparan sulfate proteoglycans of rat glomerulus

DEFF Research Database (Denmark)

Beavan, L A; Davies, M; Couchman, J R

1989-01-01

The metabolic turnover of rat glomerular proteoglycans in vivo was investigated. Newly synthesized proteoglycans were labeled during a 7-h period after injecting sodium [35S]sulfate intraperitoneally. At the end of the labeling period a chase dose of sodium sulfate was given. Subsequently......-propanesulfonate-4 M guanidine hydrochloride, a procedure which solubilized greater than 95% of the 35S-labeled macromolecules. Of these 11-13% was immunoprecipitated by an antiserum against heparan sulfate proteoglycan which, in immunolocalization experiments, showed specificity for staining the basement membrane...

Protective Effect of Daikenchuto on Dextran Sulfate Sodium-Induced Colitis in Mice.

Science.gov (United States)

Matsunaga, Takaharu; Hashimoto, Shinichi; Yamamoto, Naoki; Kawasato, Ryo; Shirasawa, Tomohiro; Goto, Atsushi; Fujisawa, Koichi; Takami, Taro; Okamoto, Takeshi; Nishikawa, Jun; Sakaida, Isao

2017-01-01

Aim . To investigate the effect of daikenchuto (TJ-100; DKT) for ulcerative colitis (UC) model mouse and assess its anti-inflammatory mechanisms. Methods . We evaluated the effects of DKT on dextran sulfate sodium- (DSS-) induced experimental colitis. First, we assessed the short-term effects of DKT using two groups: 5% DSS group and 5% DSS with DKT group. Colon length; histological scores; and interleukin- (IL-) 10, IL-1 β , and tumor necrosis factor- α mRNA expression profiles were analyzed using real-time PCR. Second, we assessed the long-term effects of DKT, by comparing survival time between 2% DSS and 2% DSS with DKT groups. Results . After 7 days, the colon lengths of DSS + DKT group were longer than those of the DSS group (mean values: 6.11 versus 5.69 cm, p DKT group maintained significantly higher levels of serum hemoglobin (13.1 versus 10.7 g/dL, p DKT group exhibited significantly longer survival time than the 2% DSS group (70 versus 44 days, p DKT prevented inflammation in the colon, indicating its potential as a new therapeutic agent for UC.

Electrochemistry of Cytochrome P450 BM3 in Sodium Dodecyl Sulfate Films

Science.gov (United States)

Udit, Andrew K.; Hill, Michael G.; Gray, Harry B.

2008-01-01

Direct electrochemistry of the cytochrome P450 BM3 heme domain (BM3) was achieved by confining the protein within sodium dodecyl sulfate (SDS) films on the surface of basal-plane graphite (BPG) electrodes. Cyclic voltammetry revealed the heme FeIII/II redox couple at −330 mV (vs. Ag/AgCl, pH 7.4). Up to 10 V/s, the peak current was linear with scan rate, allowing us to treat the system as surface-confined within this regime. The standard heterogeneous rate constant determined at 10 V/s was estimated to be 10 s−1. Voltammograms obtained for the BM3-SDS-BPG system in the presence of dioxygen exhibited catalytic waves at the onset of FeIII reduction. The altered heme reduction potential of the BM3-SDS-graphite system indicates that SDS is likely bound in the enzyme active-site region. Compared to other P450-surfactant systems, we find redox potentials and electron transfer rates that differ by ~ 100 mV and > 10-fold, respectively, indicating that the nature of the surfactant environment has a significant effect on the observed heme redox properties. PMID:17129070

THE IMPACT OF BIOSTIMULATION ON THE FATE OF SULFATE AND ASSOCIATED SULFUR DYNAMICS IN GROUNDWATER

Science.gov (United States)

Miao, Ziheng; Carreón-Diazconti, Concepcion; Carroll, Kenneth C.; Brusseau, Mark L.

2014-01-01

The impact of electron-donor addition on sulfur dynamics for a groundwater system with low levels of metal contaminants was evaluated with a pilot-scale biostimulation test conducted at a former uranium mining site. Geochemical and stable-isotope data collected before, during, and after the test were analyzed to evaluate the sustainability of sulfate reducing conditions induced by the test, the fate of hydrogen sulfide, and the impact on aqueous geochemical conditions. The results of site characterization activities conducted prior to the test indicated the absence of measurable bacterial sulfate reduction. The injection of an electron donor (ethanol) induced bacterial sulfate reduction, as confirmed by an exponential decrease of sulfate concentration in concert with changes in oxidation-reduction potential, redox species, alkalinity, production of hydrogen sulfide, and fractionation of δ34S-sulfate. High, stoichiometrically-equivalent hydrogen sulfide concentrations were not observed until several months after the start of the test. It is hypothesized that hydrogen sulfide produced from sulfate reduction was initially sequestered in the form of iron sulfides until the exhaustion of readily reducible iron oxides associated with the sediment. The fractionation of δ34S for sulfate was atypical, wherein the enrichment declined in the latter half of the experiment. It was conjectured that mixing effects associated with the release of sulfate from sulfate minerals associated with the sediments, along with possible sulfide re-oxidation contributed to this behavior. The results of this study illustrate the biogeochemical complexity that is associated with in-situ biostimulation processes involving bacterial sulfate reduction. PMID:25016586

The impact of biostimulation on the fate of sulfate and associated sulfur dynamics in groundwater

Science.gov (United States)

Miao, Ziheng; Carreón-Diazconti, Concepcion; Carroll, Kenneth C.; Brusseau, Mark L.

2014-08-01

The impact of electron-donor addition on sulfur dynamics for a groundwater system with low levels of metal contaminants was evaluated with a pilot-scale biostimulation test conducted at a former uranium mining site. Geochemical and stable-isotope data collected before, during, and after the test were analyzed to evaluate the sustainability of sulfate reducing conditions induced by the test, the fate of hydrogen sulfide, and the impact on aqueous geochemical conditions. The results of site characterization activities conducted prior to the test indicated the absence of measurable bacterial sulfate reduction. The injection of an electron donor (ethanol) induced bacterial sulfate reduction, as confirmed by an exponential decrease of sulfate concentration in concert with changes in oxidation-reduction potential, redox species, alkalinity, production of hydrogen sulfide, and fractionation of δ34S-sulfate. High, stoichiometrically-equivalent hydrogen sulfide concentrations were not observed until several months after the start of the test. It is hypothesized that hydrogen sulfide produced from sulfate reduction was initially sequestered in the form of iron sulfides until the exhaustion of readily reducible iron oxides within the sediment. The fractionation of δ34S for sulfate was atypical, wherein the enrichment declined in the latter half of the experiment. It was conjectured that mixing effects associated with the release of sulfate from sulfate minerals associated with the sediments, along with possible sulfide re-oxidation contributed to this behavior. The results of this study illustrate the biogeochemical complexity that is associated with in-situ biostimulation processes involving bacterial sulfate reduction.

Enhanced hydrogen production by coupled system of Halobacterium halobium and chloroplast after entrapment within reverse micelles

Energy Technology Data Exchange (ETDEWEB)

Singh, A.; Dubey, R.S. [Banaras Hindhu University, Varanasi (India). Dept. of Biochemistry; Pandey, K.D. [Banaras Hindhu University, Varanasi (India). Dept. of Botany

1999-08-01

Reverse micelles were used for the enhanced rate of photoproduction of hydrogen using the coupled system of Halobacterium halobium and chloroplasts organelles. Different combinations of organic solvents and surfactants were used for generating reverse micelles. A several fold enhancement in the rate of H{sub 2} production was observed when the coupled system was entrapped within reverse micelles as compared to the aqueous suspension where no detectable H{sub 2} was produced. The coupled system immobilized in reverse micelles formed by sodium lauryl sulfate and carbon tetrachloride yielded maximum rate of H{sub 2} evolution. The optimum temperature for such hydrogen production was 40{sup o}C using light of 520-570 nm wavelength and 100 lux intensity. (author)

Polyelectrolyte-surfactant complexes formed by poly[3,5-bis(trimethylammoniummethyl)4-hydroxystyrene iodide]-block-poly(ethylene oxide) and sodium dodecyl sulfate in aqueous solutions

Czech Academy of Sciences Publication Activity Database

Štěpánek, M.; Matějíček, P.; Procházka, K.; Filippov, Sergey K.; Angelov, Borislav; Šlouf, Miroslav; Mountrichas, G.; Pispas, S.

2011-01-01

Roč. 27, č. 9 (2011), s. 5275-5281 ISSN 0743-7463 R&D Projects: GA MŠk ME09059; GA ČR GCP205/11/J043; GA ČR GAP208/10/0353 Institutional research plan: CEZ:AV0Z40500505 Keywords : polyelectrolyte-surfactant complexes * sodium dodecyl sulfate * small-angle X-ray scattering Subject RIV: CD - Macromolecular Chemistry Impact factor: 4.186, year: 2011

Fluorometric determination of proteins using the yttrium(III)-sodium lauryl sulfate-rutin-protein system

International Nuclear Information System (INIS)

Liu Shufang; Yang Jinghe; Wu Xia; Wang Fei; Wang Feng; Jia Zhen

2006-01-01

It is found that rutin can react with yttrium(III) (Y 3+ ), and emits fluorescence of rutin. The intensity is greatly enhanced by proteins in the presence of sodium lauryl sulfate (SLS). Based on this, a new fluorimetric method of determination of proteins is developed. Under optimum conditions, the enhanced intensity of fluorescence is in proportion to the concentration of proteins in the range of 5.0x10 -9 -1.0x10 -5 g/mL for bovine serum albumin (BSA), 3.0x10 -8 -1.0x10 -5 g/mL for human serum albumin (HSA) and 1.0x10 -7 -2.0x10 -5 g/mL for egg albumin (EA). Their detection limits (S/N=3) are 1.6x10 -9 , 9.8x10 -9 and 2.1x10 -8 g/mL, respectively. The interaction mechanism is also studied

Fluorometric determination of proteins using the yttrium(III)-sodium lauryl sulfate-rutin-protein system

Energy Technology Data Exchange (ETDEWEB)

Liu Shufang [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Yang Jinghe [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)]. E-mail: yjh@sdu.edu.cn; Wu Xia [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Wang Fei [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Wang Feng [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Jia Zhen [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)

2006-04-15

It is found that rutin can react with yttrium(III) (Y{sup 3+}), and emits fluorescence of rutin. The intensity is greatly enhanced by proteins in the presence of sodium lauryl sulfate (SLS). Based on this, a new fluorimetric method of determination of proteins is developed. Under optimum conditions, the enhanced intensity of fluorescence is in proportion to the concentration of proteins in the range of 5.0x10{sup -9}-1.0x10{sup -5}g/mL for bovine serum albumin (BSA), 3.0x10{sup -8}-1.0x10{sup -5}g/mL for human serum albumin (HSA) and 1.0x10{sup -7}-2.0x10{sup -5}g/mL for egg albumin (EA). Their detection limits (S/N=3) are 1.6x10{sup -9}, 9.8x10{sup -9} and 2.1x10{sup -8}g/mL, respectively. The interaction mechanism is also studied.

Flour sodium dodecyl sulfate (SDS)-extractable protein level as a cookie flour quality indicator.

Science.gov (United States)

Pareyt, Bram; Bruneel, Charlotte; Brijs, Kristof; Goesaert, Hans; Delcour, Jan A

2010-01-13

Flour characteristics of laboratory-milled flour fractions of two wheat cultivars were related to their cookie-baking performance. Cultivar (cv.) Albatros wheat milling yielded fractions with lower damaged starch (DS) and arabinoxylan levels and higher sodium dodecyl sulfate-extractable protein (SDSEP) levels than did cv. Meunier wheat milling. During baking, cv. Albatros flour doughs spread faster and set later than their cv. Meunier counterparts and, hence, resulted in larger cookie diameters. DS levels negatively affected spread rate during both cv. Albatros (R2=0.68) and cv. Meunier (R2=0.51) cookie baking. SDSEP levels also influenced cookie quality. The use of flour heat-treated to reduce its SDSEP levels to different degrees led to reduction of the set time (R2=0.90). It was deduced that larger gluten polymer sizes limit dough spread time during baking and that, apart from DS level, the SDSEP level is an indicator for cookie flour quality.

Effect of Arctium lappa L. in the dextran sulfate sodium colitis mouse model.

Science.gov (United States)

Huang, Tzou-Chi; Tsai, Shinn-Shyong; Liu, Li-Fang; Liu, Yu Lin; Liu, Hung-Jen; Chuang, Kuo Pin

2010-09-07

To analyze the possible protective role of Arctium lappa L. (AL) in a murine model of ulcerative colitis (UC). BALB/c mice were administered 100 mg/kg AL powder orally each day. After 7 d, colitis was induced by administration of dextran sulfate sodium (DSS) (5% W/V) in drinking water for a further 8 consecutive days. Diarrhea and bloody stools as well as colonic histology were observed. The level of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) in colonic sections were detected by immunohistochemistry. There were significant differences in mean body weight values and disease activity indices between controls and AL-treated animals. Moreover, the histological findings showed that AL treatment can prevent mucosal edema, submucosal erosions, ulceration, inflammatory cell infiltration and colon damage. In addition, immunohistochemistry analysis showed that the levels of the inflammatory cytokines, IL-6 and TNF-alpha were also decreased in AL-treated groups. We suggest that AL can prevent intestinal damage and decrease inflammatory cytokines in mice with DSS-induced colitis. Thus, AL could prove to be a useful food for UC.

Ultrahigh figure-of-merit for hydrogen generation from sodium borohydride using ternary metal catalysts

Science.gov (United States)

Hu, Lunghao; Ceccato, R.; Raj, R.

We report further increase in the figure-of-merit (FOM) for hydrogen generation from NaBH 4 than reported in an earlier paper [1], where a sub-nanometer layer of metal catalysts are deposited on carbon nanotube paper (CNT paper) that has been functionalized with polymer-derived silicon carbonitride (SiCN) ceramic film. Ternary, Ru-Pd-Pt, instead of the binary Pd-Pt catalyst used earlier, together with a thinner CNT paper is shown to increase the figure-of-merit by up to a factor of six, putting is above any other known catalyst for hydrogen generation from NaBH 4. The catalysts are prepared by first impregnating the functionalized CNT-paper with solutions of the metal salts, followed by reduction in a sodium borohydride solution. The reaction mechanism and the catalyst efficiency are described in terms of an electric charge transfer, whereby the negative charge on the BH 4 - ion is exchanged with hydrogen via the electronically conducting SiCN/CNT substrate [1].

Alkali free hydrolysis of sodium borohydride for hydrogen generation under pressure

Energy Technology Data Exchange (ETDEWEB)

Ferreira, M.J.F.; Pinto, A.M.F.R. [Centro de Estudos de Fenomenos de Transporte, Departamento de Engenharia Quimica, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias s/n, 4200-465 Porto (Portugal); Gales, L. [Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto and Instituto de Ciencias Biomedicas Abel Salazar, Largo Prof. Abel Salazar 2, 4099-003 Porto (Portugal); Fernandes, V.R.; Rangel, C.M. [Laboratorio Nacional de Energia e Geologia - LNEG, Fuel Cells and Hydrogen Unit Estrada do Paco do Lumiar 22, 1649-038 Lisboa (Portugal)

2010-09-15

The present study is related with the production of hydrogen gas (H{sub 2}), at elevated pressures and with high gravimetric storage density, to supply a PEM fuel cell on-demand. To achieve this goal, solid sodium borohydride (NaBH{sub 4}) was mixed with a proper amount of a powder reused nickel-ruthenium based catalyst (Ni-Ru based/NaBH{sub 4}: 0.2 and 0.4 g/g; {approx}150 times reused) inside the bottom of a batch reactor. Then, a stoichiometric amount of pure liquid water (H{sub 2}O/NaBH{sub 4}: 2-8 mol/mol) was added and the catalyzed NaBH{sub 4} hydrolysis evolved, in the absence of an alkali inhibitor. In this way, this research work is designated alkali free hydrolysis of NaBH{sub 4} for H{sub 2} generation. This type of hydrolysis is excellent from an environmental point of view because it does not involve strongly caustic solutions. Experiments were performed in three batch reactors with internal volumes 646, 369 and 229 cm{sup 3}, and having different bottom geometries (flat and conical shapes). The H{sub 2} generated was a function of the added water and completion was achieved with H{sub 2}O/NaBH{sub 4} = 8 mol/mol. The results show that hydrogen yields and rates increase remarkably increasing both system temperature and pressure. Reactor bottom shape influences deeply H{sub 2} generation: the conical bottom shape greatly enhances the rate and practically eliminates the reaction induction time. Our system of compressed hydrogen generation up to 1.26 MPa shows 6.3 wt% and 70 kg m{sup -3}, respectively, for gravimetric and volumetric hydrogen storage capacities (materials-only basis) and therefore is a viable hydrogen storage candidate for portable applications. (author)

STUDY OF HYDROGEN SULFIDE REMOVAL FROM GROUNDWATER

Directory of Open Access Journals (Sweden)

T. Lupascu

2013-06-01

Full Text Available The process of the hydrogen sulfide removal from the underground water of the Hancesti town has been investigated. By oxygen bubbling through the water containing hydrogen sulfide, from the Hancesti well tube, sulfur is deposited in the porous structure of studied catalysts, which decreases their catalytic activity. Concomitantly, the process of adsorption / oxidation of hydrogen sulfide to sulfate take place. The kinetic research of the hydrogen sulfide removal from the Hancesti underground water, after its treatment by hydrogen peroxide, proves greater efficiency than in the case of modified carbonic adsorbents. As a result of used treatment, hydrogen sulfide is completely oxidized to sulfates

A comparison study between sodium dodecyl sulfate and sodium dodecyl sulfonate with respect to the thermodynamic properties, micellization, and interaction with poly(ethylene glycol) in aqueous solutions

Energy Technology Data Exchange (ETDEWEB)

Sadeghi, Rahmat, E-mail: rsadeghi@uok.ac.ir [Department of Chemistry, University of Kurdistan, Sanandaj (Iran, Islamic Republic of); Shahabi, Somayyeh [Department of Chemistry, University of Kurdistan, Sanandaj (Iran, Islamic Republic of)

2011-09-15

Graphical abstract: Apparent molar volume against molality: o, {center_dot}, and {Delta}, respectively in water, (1 and 4) wt% PEG solution at 293.15 K; x, {Delta}, and lozenge, respectively in water, (1 and 4) wt% PEG solution at 313.15 K. Research Highlights: > C{sub 12}H{sub 25}SO{sub 3}Na(SDSn) was seen to interact with PEG more weakly than C{sub 12}H{sub 25}SO{sub 4}Na(SDS). > The constraints on molecular mobility of SDS micelles are larger than those of SDSn. > Entropy change on micellization for SDSn is larger than those for SDS. > Micelle formation of SDS is less endothermic and more spontaneous than that of SDSn. > Micelles of SDS have smaller aggregation number than that of SDSn. - Abstract: The density, sound velocity, and conductivity measurements were performed on aqueous solutions of sodium dodecyl sulfate (C{sub 12}H{sub 25}SO{sub 4}Na) or sodium dodecyl sulfonate (C{sub 12}H{sub 25}SO{sub 3}Na) in the absence and presence of poly(ethylene glycol) (PEG) at different temperatures. Changes in the apparent molar volumes and isentropic compressibilities upon micellization were derived using a pseudophase-transition approach and the infinite dilution apparent molar properties of the monomer and micellar form of C{sub 12}H{sub 25}SO{sub 4}Na and C{sub 12}H{sub 25}SO{sub 3}Na were determined. Variations of the critical micelle concentrations (CMCs) of both surfactants in the solutions investigated with temperature were obtained from which thermodynamic parameters of micellization were estimated. It was found that at low temperature the micelle formation process is endothermic and therefore, this process must be entropically driven. However, upon increasing the temperature, the enthalpic factor becomes more significant and, at temperatures higher than 303.15 K the micellization is enthalpy driven. The interactions between C{sub 12}H{sub 25}SO{sub 4}Na/C{sub 12}H{sub 25}SO{sub 3}Na and PEG were studied and it was found that sodium alkyl sulfonates were seen

The effects of temperature on the leaching behavior of cement waste forms: The cement/sodium sulfate system

International Nuclear Information System (INIS)

Fuhrmann, M.; Pietrzak, R.; Heiser, J.; Franz, E.M.; Colombo, P.

1989-10-01

The leaching mechanisms of simulated low-level radioactive waste forms are being determined as support for development of an accelerated leach test. Two approaches are being used: (1) comparisons of leaching data with results of a model that describes diffusion from a finite cylinder, and (2) observation of the leaching process at temperatures between 20 degree C and 65 degree C. To provide results that can be used for modeling, leaching at elevated temperatures must change neither the leaching mechanism nor the structural controls of leaching such as the porosity. Releases of 137 Cs, 85 Sr, calcium, sodium and potassium from portland cement containing sodium sulfate, as a simulated evaporator sludge, have been determined under a variety of experimental conditions. Data from the leach tests were compared to model results for diffusion from the finite cylinder. While most leaching appears to be diffusion controlled, notable exceptions occur. For all samples activation energies ranging between 6 and 11 Kcal/mole have been calculated from the relationship of the effective diffusion coefficient to increasing temperature, close to the expected value of 5 Kcal/mole for diffusion. 11 refs., 4 figs., 2 tabs

A new probe of solvent accessibility of bound photosensitizers. 1. Ruthenium(II) and osmium(II) photosensitizers in sodium lauryl sulfate micelles

International Nuclear Information System (INIS)

Hauenstein, B.L. Jr.; Dressick, W.J.; Buell, S.L.; Demas, J.N.; DeGraff, B.A.

1983-01-01

A new method of measuring solvent accessibility of photosensitizers bound to organized media is presented. In particular, the solvent accessibility of a series of ruthenium(II) and osmium(II) photosensitizers bound to sodium lauryl sulfate micelles has been determined. The method takes advantage of the large solvent deuterium effect on the excited-state lifetimes of these complexes. The solvent accessibility of the bound complexes correlates with the hydrophobicity of the ligands. The potential application of this method to a variety of other systems is mentioned

Effect of metakaolin on external sulfate attack

Energy Technology Data Exchange (ETDEWEB)

Ramlochan, T.; Thomas, M. [Toronto Univ., Dept. of Civil Engineering, ON (Canada)

2000-07-01

The effect of high reactivity metakaolin (HRM) on the sulfate resistance of mortars was studied. Mortar bars with three cements of varying C{sub 3}A content were used for the experiment. After a six month exposure to a 5 per cent solution of sodium sulfate, mortar bars incorporating any level of HRM as a partial replacement for a high-C{sub 3}A was considered 'moderately sulfate resistant'; mortar bars with HRM and a moderate or low C{sub 3}A content as 'high sulfate resistant'. It was also determined that for long term sulfate resistance 15 per cent HRM or more may be required, depending on the C{sub 3}A content. The performance of HRM was found to be significantly influenced by the water-cementitious material ratio, and in turn, by permeability, suggesting that HRM might increase sulfate resistance more by lowering the permeability of the concrete than by any chemical action. 7 refs., 4 tabs., 7 figs.

The kinetics of the cerium(IV)-uranium(IV) reaction at low sulfate concentrations

International Nuclear Information System (INIS)

Michaille, P.; Kikindai, T.

1977-01-01

The rate of oxidation of uranium(IV) by cerium(IV) was measured with a stopped-flow spectrophotometer at sulfuric acid concentrations of 2 x 10 -6 to 0.5 M. At a constant hydrogen ion concentration of 0.5 M, the maximum rate constant was observed for 2 x 10 -3 M sulfuric acid; at that concentration, two sulfate ions were involved in the activated complex. The dependence of the rate constant on the hydrogen ion concentration showed that the reaction paths involving one or two sulfate ions also involved one hydroxyl ion, whereas one hydrogen ion was involved in the five sulfate dependent path. Spectrophotometric measurements supported the existence of a hydrolyzed monosulfatocomplex of cerium(IV). (author)

Hydrogen anode for nitrate waste destruction. Revision 2

International Nuclear Information System (INIS)

Hobbs, D.T.; Kalu, E.E.; White, R.E.

1996-01-01

Large quantities of radioactive and hazardous wastes have been generated from nuclear materials production during the past fifty years. Processes are under evaluation to separate the high level radioactive species from the waste and store them permanently in the form of durable solids. The schemes proposed will separate the high level radioactive components, cesium-137 and strontium-90, into a small volume for incorporation into a glass wasteform. The remaining low-level radioactive waste contain species such as nitrites and nitrates that are capable of contaminating ground water. Electrochemical destruction of the nitrate and nitrite before permanent storage has been proposed. Not only will the electrochemical processing destroy these species, the volume of the waste could also be reduced. The use of a hydrogen gas-fed anode and an acid anolyte in an electrochemical cell used to destroy nitrate was demonstrated. A mixed Na 2 SO 4 /H 2 SO 4 anolyte was shown to favor the nitrate cell performance, and the generation of a higher hydroxide ion concentration in the catholyte. The suggested scheme is an apparent method of sodium sulfate disposal and a possible means through which ammonia (to ammonium sulfate, fertilizer) and hydrogen gas could be recycled through the anode side of the reactor. This could result in a substantial savings in the operation of a nitrate destruction cell

Method of preparing Ru-immobilized polymer-supported catalyst for hydrogen generation from NaBH{sub 4} solution

Energy Technology Data Exchange (ETDEWEB)

Chen, Ching-Wen; Chen, Chuh-Yung; Huang, Yao-Hui [Department of Chemical Engineering, National Cheng Kung University, No.1, University Road, Tainan City 70101 (China)

2009-03-15

A method of preparing a polymer-supported catalyst for hydrogen generation is introduced in this article. This polymer-supported catalyst is the structure of ruthenium (Ru) nanoparticle immobilized on a monodisperse polystyrene (PSt) microsphere. The diameter of the Ru nanoparticle is around 16 nm, and the diameter of the PSt microsphere is 2.65 um. This preparation method is accomplished by two unique techniques: one is sodium lauryl sulfate/sodium formaldehyde sulfoxylate (SLS/SFS) interface-initiated system, the other is 2-methacrylic acid 3-(bis-carboxymethylamino)-2-hydroxy-propyl ester (GMA-IDA) chelating monomer. By taking advantage of these two techniques, Ru{sup 3+} ion will be chelated and then reduced to Ru{sup (0)} nanoparticle over PSt surface predominantly. The hydrolysis of alkaline sodium borohydride (NaBH{sub 4}) solution catalyzed by this Ru-immobilized polymer-supported catalyst is also examined in this article. It reveals that the hydrogen generation rate is 215.9 ml/min g-cat. in a diluted solution containing 1 wt.% NaBH{sub 4} and 1 wt.% NaOH, and this Ru-immobilized polymer-supported catalyst could be recycled during the reaction. (author)

Stability of polymyxin B sulfate diluted in 0.9% sodium chloride injection and stored at 4 or 25 degrees C.

Science.gov (United States)

He, Jie; Figueroa, Deborah A; Lim, Tze-Peng; Chow, Diana S; Tam, Vincent H

2010-07-15

The stability of polymyxin B sulfate in infusion bags containing 0.9% sodium chloride injection stored at 4 and 25 degrees C was studied. Seven manufacturing batches of polymyxin B from different sources were tested. The products were reconstituted in sterile water for injection, diluted in infusion bags containing 0.9% sodium chloride injection, and stored at room temperature (25 degrees C) or under refrigeration (4 degrees C). Samples were withdrawn at the same time on days 0, 1, 2, 3, 5, and 7. A modified microbiological assay was used to determine the concentrations, as indicated by zones of inhibition, of polymyxin B. Bordetella bronchiseptica served as the reference organism. Stability was defined as retention of >90% of the initial concentration. The decomposition kinetics of polymyxin B in 0.9% sodium chloride injection were evaluated by plotting the polymyxin B concentration remaining versus time. On average, the samples retained over 90% of their initial concentration for up to two days at both storage temperatures. All samples retained over 90% of their initial concentration at 24 hours. The decomposition kinetics of polymyxin B in infusion bags containing 0.9% sodium chloride injection exhibited pseudo-first-order kinetics, with rate constants of 0.024-0.075 day(-1) at 25 degrees C and 0.022-0.043 day(-1) at 4 degrees C (p > 0.05). Polymyxin B was stable for at least one day when stored at 4 or 25 degrees C in infusion bags containing 0.9% sodium chloride injection. Stability did not differ significantly between the two storage temperatures.

Genetics and Molecular Biology of Hydrogen Metabolism in Sulfate-Reducing Bacteria

Energy Technology Data Exchange (ETDEWEB)

Wall, Judy D. [Univ. of Missouri, Columbia, MO (United States)

2014-12-23

The degradation of our environment and the depletion of fossil fuels make the exploration of alternative fuels evermore imperative. Among the alternatives is biohydrogen which has high energy content by weight and produces only water when combusted. Considerable effort is being expended to develop photosynthetic systems -- algae, cyanobacteria, and anaerobic phototrophs -- for sustainable H₂ production. While promising, this approach also has hurdles such as the harvesting of light in densely pigmented cultures that requires costly constant mixing and large areas for exposure to sunlight. Little attention is given to fermentative H₂ generation. Thus understanding the microbial pathways to H₂ evolution and metabolic processes competing for electrons is an essential foundation that may expand the variety of fuels that can be generated or provide alternative substrates for fine chemical production. We studied a widely found soil anaerobe of the class Deltaproteobacteria, a sulfate-reducing bacterium to determine the electron pathways used during the oxidation of substrates and the potential for hydrogen production.

Allergic contact dermatitis from ophthalmic products: can pre-treatment with sodium lauryl sulfate increase patch test sensitivity?

Science.gov (United States)

Corazza, Monica; Virgili, Annarosa

2005-05-01

In patients suspected of allergic contact dermatitis because of topical ophthalmic medicaments, patch tests performed with patients' own products are often negative. The irritant anionic surfactant sodium lauryl sulfate (SLS) may alter the stratum corneum and increase antigen penetration. Pre-treatment of the skin with SLS 0.5% for 24 h was performed in the sites of patch tests with patients' own products in 15 selected patients. In patients previously negative to their own products tested with conventional patch tests, SLS pre-treatment showed 6 new relevant positive reactions and induced a stronger positive reaction in 1 patient. SLS pre-treatment could be proposed as an alternative promising method, which may increase sensitivity of patch tests with patients' own products.

Voltammetric Determination of Ivabradine Hydrochloride Using Multiwalled Carbon Nanotubes Modified Electrode in Presence of Sodium Dodecyl Sulfate

Directory of Open Access Journals (Sweden)

Ali Kamal Attia

2017-04-01

Full Text Available Purpose: A new sensitive sensor was fabricated for the determination of ivabradine hydrochloride (IH based on modification with multiwalled carbon nanotubes using sodium dodecyl sulfate as micellar medium to increase the sensitivity. Methods: The electrochemical behavior of IH was studied in Britton-Robinson buffer (pH: 2.0-11.0 using cyclic and differential pulse voltammetry. Results: The voltammetric response was linear over the range of 3.984 x 10-6-3.475 x 10-5 mol L-1. The limits of detection and quantification were found to be 5.160 x 10-7 and 1.720 x 10-6 mol L-1, respectively. Conclusion: This method is suitable for determination of IH in tablets and plasma.

Quantitation of yeast total proteins in sodium dodecyl sulfate-polyacrylamide gel electrophoresis sample buffer for uniform loading.

Science.gov (United States)

Sheen, Hyukho

2016-04-01

Proteins in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) sample buffer are difficult to quantitate due to SDS and reducing agents being in the buffer. Although acetone precipitation has long been used to clean up proteins from detergents and salts, previous studies showed that protein recovery from acetone precipitation varies from 50 to 100% depending on the samples tested. Here, this article shows that acetone precipitates proteins highly efficiently from SDS-PAGE sample buffer and that quantitative recovery is achieved in 5 min at room temperature. Moreover, precipitated proteins are resolubilized with urea/guanidine, rather than with SDS. Thus, the resolubilized samples are readily quantifiable with Bradford reagent without using SDS-compatible assays. Copyright © 2016 Elsevier Inc. All rights reserved.

XRD, SEM and infrared study into the intercalation of sodium hexadecyl sulfate (SHS) into hydrocalumite.

Science.gov (United States)

Zhang, Ping; Wang, Tianqi; Zhang, Longlong; Wu, Daishe; Frost, Ray L

2015-12-05

Hydrocalumite (CaAl-LDH-Cl) interacted with a natural anionic surfactant, sodium hexadecyl sulfate (SHS), was performed using an intercalation method. To understand the intercalation behavior and characterize the resulting products, powder X-ray diffraction (XRD), scan electron microscopy (SEM) and mid-infrared (MIR) spectroscopy combined with near-infrared (NIR) spectroscopy technique were used. The XRD analysis indicated that SHS was intercalated into CaAl-LDH-Cl successfully, resulting in an expansion of the interlayer (from 0.78 nm to 2.74 nm). The bands of C-H stretching vibrations of SHS were observed in the near-infrared spectra, which indicated that the resulting products were indeed CaAl-LDH-SHS. In addition, the bands of water stretching vibrations and OH groups shifted to higher wavenumbers when SHS was intercalated into CaAl-LDH-Cl interlayer space. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of Sodium Lauryl Sulfate-Fumaric Acid Coupled Addition on the In Vitro Rumen Fermentation with Special Regard to Methanogenesis

Directory of Open Access Journals (Sweden)

M. A. Abdl-Rahman

2010-01-01

Full Text Available The aim of the current study was to evaluate the effect of sodium lauryl sulfate-fumaric acid coupled addition on in vitro methangenesis and rumen fermentation. Evaluation was carried out using in vitro gas production technique. Ruminal contents were collected from five steers immediately after slaughtering and used for preparation of inoculums of mixed rumen microorganisms. Rumen fluid was then mixed with the basal diet of steers and used to generate four treatments, negative control (no additives, sodium lauryl sulfate (SLS treated, fumaric acid treated, and SLS-fumaric acid coupled addition treated. The results revealed that, relative to control, efficiency in reduction of methanogenesis was as follows: coupled addition > SLS-addition > fumaric acid addition. Both SLS-addition and SLS-fumaric acid coupled addition demonstrated a decremental effect on ammonia nitrogen (NH3–N, total short chain volatile fatty acids (SCVFAs concentrations and the amount of substrate degraded, and an increment effect on microbial mass and microbial yield (YATP. Nevertheless, fumaric acid did not alter any of the previously mentioned parameters but induced a decremental effect on NH3–N. Furthermore, both fumaric acid and SLS-fumaric acid coupled addition increased propionate at the expense of acetate and butyrate, while, defaunation increased acetate at the expense of propionate and butyrate. The pH value was decreased by all treatments relative to control, while, cellulase activity did not differ by different treatments. The current study can be promising strategies for suppressing ruminal methane emissions and improving ruminants feed efficiency.

Effect of sodium lauryl sulfate-fumaric Acid coupled addition on the in vitro rumen fermentation with special regard to methanogenesis.

Science.gov (United States)

Abdl-Rahman, M A; Sawiress, F A R; Abd El-Aty, A M

2010-01-01

The aim of the current study was to evaluate the effect of sodium lauryl sulfate-fumaric acid coupled addition on in vitro methangenesis and rumen fermentation. Evaluation was carried out using in vitro gas production technique. Ruminal contents were collected from five steers immediately after slaughtering and used for preparation of inoculums of mixed rumen microorganisms. Rumen fluid was then mixed with the basal diet of steers and used to generate four treatments, negative control (no additives), sodium lauryl sulfate (SLS) treated, fumaric acid treated, and SLS-fumaric acid coupled addition treated. The results revealed that, relative to control, efficiency in reduction of methanogenesis was as follows: coupled addition > SLS-addition > fumaric acid addition. Both SLS-addition and SLS-fumaric acid coupled addition demonstrated a decremental effect on ammonia nitrogen (NH(3)-N), total short chain volatile fatty acids (SCVFAs) concentrations and the amount of substrate degraded, and an increment effect on microbial mass and microbial yield (Y(ATP)). Nevertheless, fumaric acid did not alter any of the previously mentioned parameters but induced a decremental effect on NH(3)-N. Furthermore, both fumaric acid and SLS-fumaric acid coupled addition increased propionate at the expense of acetate and butyrate, while, defaunation increased acetate at the expense of propionate and butyrate. The pH value was decreased by all treatments relative to control, while, cellulase activity did not differ by different treatments. The current study can be promising strategies for suppressing ruminal methane emissions and improving ruminants feed efficiency.

Experimental study of hydrogen jet ignition and jet extinguishment

International Nuclear Information System (INIS)

Wierman, R.W.

1979-04-01

Two phases are described of an experimental study that investigated: (1) the ignition characteristics of hydrogen--sodium jets, (2) the formation of hydrogen in sodium--humid air atmospheres, and (3) the extinguishment characteristics of burning hydrogen--sodium jets. Test conditions were similar to those postulated for highly-improbable breeder reactor core melt-through accidents and included: jet temperature, jet velocity, jet hydrogen concentration, jet sodium concentration, atmospheric oxygen concentration, and atmospheric water vapor concentration

Improving the hardness of dry granulated tablets containing sodium lauryl sulfate.

Science.gov (United States)

Moore, Francis; Okelo, Geoffrey; Colón, Ivelisse; Kushner, Joseph

2010-11-15

The impact of the addition of a wetting agent, the surfactant sodium lauryl sulfate (SLS), on the tablet hardness of a dry granulated, solid oral dosage form was investigated. In three batches, SLS was added concurrently with: (1) a poorly soluble, highly hydrophobic active pharmaceutical ingredient (API) and the other excipients prior to the initial blending step, (2) magnesium stearate prior to roller compaction, or (3) magnesium stearate prior to tableting. A fourth batch, which did not contain SLS, served as a control. The maximum hardness of 100 mg, 1/4″-SRC tablets for the four batches--SLS added initially, prior to roller compaction, prior to tableting, and no SLS--were 61±3, 71±3, 89±5, and 86±3N, respectively, suggesting reduced processing of SLS improves tablet hardness by ∼50%. Dissolution of the tablets in 900 ml of simulated gastric fluid with paddles at 75 rpm showed that: (1) there was no impact on the insertion point of SLS into the process on API dissolution, and (2) that the presence of SLS improved dissolution by 5% compared to the control tablets. Adding SLS just prior to tableting can improve tablet hardness and yield similar dissolution performance relative to SLS addition prior to the initial blending step. Copyright © 2010 Elsevier B.V. All rights reserved.

Stratum corneum cytokines and skin irritation response to sodium lauryl sulfate.

Science.gov (United States)

De Jongh, Cindy M; Verberk, Maarten M; Withagen, Carien E T; Jacobs, John J L; Rustemeyer, Thomas; Kezic, Sanja

2006-06-01

Little is known about cytokines involved in chronic irritant contact dermatitis. Individual cytokine profiles might explain at least part of the differences in the individual response to irritation. Our objective was to investigate the relation between baseline stratum corneum (SC) cytokine levels and the skin response to a single and a repeated irritation test. This study also aimed to determine changes in SC cytokine levels after repeated irritation. Transepidermal water loss (TEWL) and erythema were measured in 20 volunteers after single 24-hr exposure to 1% sodium lauryl sulfate (SLS), and during and after repeated exposure to 0.1% SLS over a 3-week period. SC cytokine levels were measured from an unexposed skin site and from the repeatedly exposed site. Interleukin (IL)-1alpha decreased by 30% after repeated exposure, while IL-1RA increased 10-fold and IL-8 increased fourfold. Baseline IL-1RA and IL-8 values were predictors of TEWL and erythema after single exposure (r = 0.55-0.61). 6 subjects showed barrier recovery during repeated exposure. Baseline IL-1RA and IL-8 levels are likely to be indicators of higher skin irritability after single exposure to SLS. Barrier repair in some of the subjects might explain the lack of agreement between the TEWL response after single and repeated irritation.

3.2.1. Synthesis, crystal and molecular structure of catena-(bis(µ1-oxalic acid)-µ3-hydrogen oxalate-di-aqua-sodium(I)).

OpenAIRE

Olga Kovalchukova*, Sergey Aldoshin, Andrey Utenyshev, Konstantin Bogenko, Valeriy Tkachev

2015-01-01

The crystal and molecular structure of catena-(bis(µ- oxalic acid)-µ-hydrogen oxalate-di-aqua-sodium(I)) was detected by X-Ray analysis. The compound crystallizes in the triclinic space group P-1, with a(Å) 6.2378(12); b(Å) 7,1115(14); c(Å) 10.489(2); α(°) 94.65(3); β(°) 100.12(3); γ(°) 97.78(3). The sodium cation in the title compound is eight coordinated and forms a square antiprism. It is surrounded by two molecules of oxalic acid, one hydrogen oxalate anion and one water molecule. Both ox...

Relative importance of nitrate and sulfate aerosol production mechanisms in urban atmospheres

International Nuclear Information System (INIS)

Middleton, P.; Kiang, C.S.

1979-01-01

The relative importance of the various sulfate and nitrate aerosol production mechanisms is calculated for different atmospheric conditions. The calculation scheme used to determine the rates of nitrate and sulfate production, based on the concept that vapor transfer to the aerosols and nitrate and sulfate formation within the aerosols are coupled kinetic processes, considers sulfate formation by ozone and hydrogen peroxide oxidation and catalytic oxidation in the presence of soot, iron and manganese of sulfite solutions and sulfuric acid condensation and nitrate formation by the liquid-phase oxidation of dissolved nitrogen oxides for different initial gas concentrations and particle compositions and sizes. It is found that sulfate production is higher under daytime conditions, primarily proceeding by mechanisms involving sulfuric acid and hydrogen peroxide, while at night oxidation processes on the surface of the aerosol film are more important. Nitrate tends to decrease nighttime sulfate production due to an increase in aerosol acidity and nitrate production is found to be higher under nighttime conditions and in the winter

Ultrasound augmented leaching of nickel sulfate in sulfuric acid and hydrogen peroxide media.

Science.gov (United States)

Li, Haoyu; Li, Shiwei; Peng, Jinhui; Srinivasakannan, Chandrasekar; Zhang, Libo; Yin, Shaohua

2018-01-01

A new method of preparation high purity nickel sulfate assisted by ultrasonic was studied. The process mechanism was analyzed by Inductively Coupled Plasma (ICP), X-ray diffraction (XRD), Scanning electron microscopy (SEM), and Energy dispersive X-ray spectrometry (EDS).The reaction mechanisms of oxidizing leaching and ultrasonic leaching were explored, respectively. Results showed that ultrasonic treatment peel off the oxide film on the surface of nickel. The leachate under strongly agitated, the yield rate of nickel sulfate was accelerate. And the reaction area was increased by the cavitation effect, the liquid-solid reaction was promoted, and the activation energy was reduced. The leaching rate of nickel reached 46.29% by conventional leaching, which takes about 5h. Under the same conditions, the ultrasonic leaching rate reached 40%, only half of the conventional leaching time. Concentration of leaching agent, reaction temperature, ultrasonic power, leaching time had significant effect on the enhancement of the leaching reaction with ultrasonic radiation. The leaching rate of 60.41% under the optimum experiment conditions as follows: sulfuric acid concentration 30%, hydrogen peroxide 10%, leaching temperature 333K, ultrasonic power 200W and leaching time 4h. The kinetic study of the system was investigated, and the reaction rates of conventional leaching and ultrasonic leaching were controlled by diffusion, and the apparent activation energies were 16.2kJ/mol and 11.83kJ/mol. Copyright © 2017. Published by Elsevier B.V.

Integrated approach for investigating the durability of self-consolidating concrete to sulfate attack

Science.gov (United States)

Bassuoni, Mohamed Tamer F.

The growing use of self-consolidating concrete (SCC) in various infrastructure applications exposed to sulfate-rich environments necessitates conducting comprehensive research to evaluate its durability to external sulfate attack. Since the reliability and adequacy of standard sulfate immersion tests have been questioned, the current thesis introduced an integrated testing approach for assessing the durability of a wide scope of SCC mixtures to external sulfate attack. This testing approach involved progressive levels of complexity from single to multiple damage processes. A new series of sulfate attack tests involving multiple field-like parameters and combined damage mechanisms (various cations, controlled pH, wetting-drying, partial immersion, freezing-thawing, and cyclic cold-hot conditions with or without sustained flexural loading) were designed to evaluate the performance (suitability) of the SCC mixtures under various sulfate attack exposure scenarios. The main mixture design variables of SCC included the type of binder (single, binary, ternary and quaternary), air-entrainment, sand-to-aggregate mass ratio and hybrid fibre reinforcement. The comprehensive database and knowledge obtained from this research were used to develop smart models (fuzzy and neuro-fuzzy inference systems) based on artificial-intelligence to evaluate and predict the performance of the SCC mixtures under various sulfate attack exposure regimes implemented in this study. In full immersion tests involving high concentration sodium and magnesium sulfate solutions with controlled pH, the low penetrability of SCC was responsible for the high durability of specimens. Ternary and quaternary cementitious systems with or without limestone materials provided a passivating layer, with or without acid neutralization capacity, which protected SCC from severe damage in the aggressive sulfuric acid and ammonium sulfate solutions. In contrast to conclusions drawn from the sodium sulfate immersion

Sodium removal disassembly and examination of the Fermi secondary sodium pump

International Nuclear Information System (INIS)

Maffei, H.P.; Funk, C.W.; Ballif, J.L.

1974-01-01

The Fermi secondary pump is a centrifugal single stage design. The pump had been operated more than 42,000 hours between 450 and 800 0 F. Sodium was drained from the pump in 1973 and the system was back filled with carbon dioxide. The pump was fabricated for 2.25 Cr-1 Mo Croloy steel. Prior to cleaning the pump was inerted and heated with 150 0 F nitrogen using the pump casing as the containment vessel. The water-vapor-nitrogen process was used in three increasing stages of water concentration. The hydrogen concentration in the discharge line was followed as an indicator of the sodium-water reaction rate. Upon completion of the hydrogen evolution, the pump was rinsed several times with hot water. Six pounds of sodium were removed from the pump during a process cycle of 79 hours including rinsing. The maximum pump temperature recorded was 175 0 F with no variation exceeding 10 0 F. The hydrogen concentration in the effluent provided a very satisfactory index for control of the reaction by adjustment of the water-vapor concentration feed to the system. Rinsing effectiveness was limited by a pool of water in the volute that was not drainable with the available system hook up. Sodium and its compounds were removed from all internal surfaces that could be observed by the first stage of disassembly. All such surfaces were coated with a black deposit. Areas above the sodium liquid level were coated with a vermillion colored oxide. Sodium was found on the (1) threads of the impeller nut lock screw, (2) impeller nut-tapered shaft interface, and (3) vapor deposited sodium was found in the oil seal

Intermittent fasting prompted recovery from dextran sulfate sodium-induced colitis in mice.

Science.gov (United States)

Okada, Toshihiko; Otsubo, Takeshi; Hagiwara, Teruki; Inazuka, Fumika; Kobayashi, Eiko; Fukuda, Shinji; Inoue, Takuya; Higuchi, Kazuhide; Kawamura, Yuki I; Dohi, Taeko

2017-09-01

Fasting-refeeding in mice induces transient hyperproliferation of colonic epithelial cells, which is dependent on the lactate produced as a metabolite of commensal bacteria. We attempted to manipulate colonic epithelial cell turnover with intermittent fasting to prompt recovery from acute colitis. Acute colitis was induced in C57BL/6 mice by administration of dextran sulfate sodium in the drinking water for 5 days. From day 6, mice were fasted for 36 h and refed normal bait, glucose powder, or lactylated high-amylose starch. On day 9, colon tissues were subjected to analysis of histology and cytokine expression. The effect of lactate on the proliferation of colonocytes was assessed by enema in vivo and primary culture in vitro . Intermittent fasting resulted in restored colonic crypts and less expression of interleukin-1β and interleukin-17 in the colon than in mice fed ad libitum . Administration of lactate in the colon at refeeding time by enema or by feeding lactylated high-amylose starch increased the number of regenerating crypts. Addition of lactate but not butyrate or acetate supported colony formation of colonocytes in vitro . In conclusion, intermittent fasting in the resolution phase of acute colitis resulted in better recovery of epithelial cells and reduced inflammation.

Ginseng Berry Extract Attenuates Dextran Sodium Sulfate-Induced Acute and Chronic Colitis

Directory of Open Access Journals (Sweden)

Wei Zhang

2016-04-01

Full Text Available This study investigates the in vivo functions of ginseng berry extract (GB as a therapy for dextran sodium sulfate (DSS-induced colitis. C57BL/6 mice were given drinking water containing DSS (3% for eight days to induce acute colitis. At the same time, the mice received an oral dose of GB (50 mg/kg once daily. The GB-treated mice were less susceptible to the development of acute colitis than were control mice treated with saline, as determined by weight loss, disease activity, and colon histology. The administration of GB to DSS-treated mice also reduced the numbers and inhibited the activation of colon-infiltrating T cells, neutrophils, intestinal CD103−CD11c+ dendritic cells (cDCs, and macrophages. In addition, GB treatment promoted the migration of CD103+CD11c+ cDCs and expansion of Foxp3+ regulatory T cells in the colons of DSS-treated mice. Similarly, in the DSS-induced chronic colitis model, GB treatment improved the macroscopic and histological appearance of the colon wall when compared to untreated control mice, as indicated by longer colon length and lower histological scores. This is the first report to show that oral administration of GB suppresses immune activation and protects against experimentally induced colitis.

Maintaining Supersaturation of Nimodipine by PVP with or without the Presence of Sodium Lauryl Sulfate and Sodium Taurocholate.

Science.gov (United States)

Pui, Yipshu; Chen, Yuejie; Chen, Huijun; Wang, Shan; Liu, Chengyu; Tonnis, Wouter; Chen, Linc; Serno, Peter; Bracht, Stefan; Qian, Feng

2018-05-30

Amorphous solid dispersion (ASD) is one of the most versatile supersaturating drug delivery systems to improve the dissolution rate and oral bioavailability of poorly water-soluble drugs. PVP based ASD formulation of nimodipine (NMD) has been marketed and effectively used in clinic for nearly 30 years, yet the mechanism by which PVP maintains the supersaturation and subsequently improves the bioavailability of NMD was rarely investigated. In this research, we first studied the molecular interactions between NMD and PVP by solution NMR, using CDCl 3 as the solvent, and the drug-polymer Flory-Huggins interaction parameter. No strong specific interaction between PVP and NMD was detected in the nonaqueous state. However, we observed that aqueous supersaturation of NMD could be significantly maintained by PVP, presumably due to the hydrophobic interactions between the hydrophobic moieties of PVP and NMD in aqueous medium. This hypothesis was supported by dynamic light scattering (DLS) and supersaturation experiments in the presence of different surfactants. DLS revealed the formation of NMD/PVP aggregates when NMD was supersaturated, suggesting the formation of hydrophobic interactions between the drug and polymer. The addition of surfactants, sodium lauryl sulfate (SLS) or sodium taurocholate (NaTC), into PVP maintained that NMD supersaturation demonstrated different effects: SLS could only improve NMD supersaturation with concentration above its critical aggregation concentration (CAC) value while not with lower concentration. Nevertheless, NaTC could prolong NMD supersaturation independent of concentration, with lower concentration outperformed higher concentration. We attribute these observations to PVP-surfactant interactions and the formation of PVP/surfactant complexes. In summary, despite the lack of specific interactions in the nonaqueous state, NMD aqueous supersaturation in the presence of PVP was attained by hydrophobic interactions between the hydrophobic

Transformation of sodium from the Rapsodie fast breeder reactor into sodium hydroxide

International Nuclear Information System (INIS)

Roger, J.; Latge, C.; Rodriguez, G.

1994-01-01

One of the major problems raised by decommissioning a fast breeder reactor (FBR) concerns the disposal of the sodium coolant. The Desora operation was undertaken to eliminate the Rapsodie primary sodium as part of the partial decommissioning program, and to develop an operational sodium treatment unit for other needs. The process involves reacting small quantities of sodium in water inside a closed vessel, producing aqueous sodium hydroxide and hydrogen gas. It is described in this work. (O.L.). 4 figs

Naked gene therapy of hepatocyte growth factor for dextran sulfate sodium-induced colitis in mice

International Nuclear Information System (INIS)

Kanbe, Takamasa; Murai, Rie; Mukoyama, Tomoyuki; Murawaki, Yoshiyuki; Hashiguchi, Ko-ichi; Yoshida, Yoko; Tsuchiya, Hiroyuki; Kurimasa, Akihiro; Harada, Ken-ichi; Yashima, Kazuo; Nishimuki, Eiji; Shabana, Noriko; Kishimoto, Yukihiro; Kojyo, Haruhiko; Miura, Kunihiko; Murawaki, Yoshikazu; Kawasaki, Hironaka; Shiota, Goshi

2006-01-01

Ulcerative colitis (UC) is progressive and relapsing disease. To explore the therapeutic effects of naked gene therapy of hepatocyte growth factor (HGF) on UC, the SRα promoter driving HGF gene was intrarectally administered to the mice in which colitis was induced by dextran sulfate sodium (DSS). Expression of the transgene was seen in surface epithelium, lamina propria, and muscularis mucosae. The HGF-treated mice showed reduced colonic mucosal damage and increased body weights, compared with control mice (P < 0.01 and P < 0.05, respectively). The HGF-treated mice displayed increased number of PCNA-positive cells and decreased number of apoptotic cells than in control mice (P < 0.01, each). Phosphorylated AKT was dramatically increased after HGF gene administration, however, phosphorylated ERK1/2 was not altered. Microarray analysis revealed that HGF induced expression of proliferation- and apoptosis-associated genes. These data suggest that naked HGF gene delivery causes therapeutic effects through regulation of many downstream genes

The various sodium purification techniques

International Nuclear Information System (INIS)

Courouau, J.L.; Masse, F.; Rodriguez, G.; Latge, C.; Redon, B.

1997-01-01

In the framework of sodium waste treatment, the sodium purification phase plays an essential role in the chain of operations leading to the transformation of the active sodium, considered as waste, into a stable sodium salt. The objectives of the purification operations are: To keep a low impurity level, particularly a low concentration in oxygen and hydrogen, in order to allow its transfer to a processing plant, and in order to avoid risks of plugging and/or corrosion in sodium facilities; To reduce the sodium activity in order to limit the dose rate close to the facilities, and in order to reduce the activity of the liquid and gaseous effluents. After a recall of the different kind of impurities that can be present in sodium, and of the different purification methods that could be associated with, the following points are highlighted: (i) Oxygen and hydrogen purification needs, and presentation of some selection criteria for a purification unit adapted to a sodium processing plant, as well as 2 cold trap concepts that are in accordance with these criteria: PSICHOS and PIRAMIDE. (ii) Tritium reduction in a bulk of liquid sodium by swamping, isotopic exchange, or permeation throughout a membrane. (iii) Caesium trapping on carbonaceous matrix. The main matrices used at present are R.V.C. (Reticulated Vitreous Carbon) and Actitex/Pica products. Tests in the laboratory and on an experimental device have demonstrated the performances of these materials, which are able to reduce sodium activity in Cs 134 and Cs 137 to very low values. The sodium purification processes as regards to the hydrogen, oxygen and caesium, that are aimed at facilitating the subsequent treatment of sodium, are therefore mastered operations. Regarding the operations associated with the reduction of the tritium activity, the methods are in the process of being qualified, or to be qualified. (author)

Thermo-acoustical analysis of sodium dodecyl sulfate: Fluconazole (antifungal drug) based micellar system in hydro-ethanol solutions for potential drug topical application

International Nuclear Information System (INIS)

Bhardwaj, Tarun; Bhardwaj, Varun; Sharma, Kundan; Gupta, Abhishek; Cameotra, Swaranjit Singh; Sharma, Poonam

2014-01-01

Highlights: • The mixed micellar system was analyzed for sodium dodecyl sulfate and fluconazole. • Early micellization was found with CMC shift towards lower surfactant concentration. • Negative ΔG m o values suggested that the micelle formation is spontaneous and feasible. • Thermo-acoustical parameters revealed the existence of intermolecular interactions within the molecules. - Abstract: Micellar systems hold excellent drug delivery applications due to their capability to solubilize a large number of hydrophobic and hydrophilic molecules. In this present work, the mixed micelle formation between the anionic surfactant sodium dodecyl sulfate (SDS) and the ‘Azole’ derivative antifungal drug fluconazole (FLZ) have been studied at four temperatures in different hydro-ethanolic solutions. The critical micelle concentration (CMC) was determined by specific conductance techniques and the experimental data was used to calculate several useful thermodynamic parameters, like standard free energy, enthalpy and entropy of micelle formation. Early micellization was found with critical micelle concentration shifting towards lower concentration (CMC) than the standard concentration of SDS in water at 25 °C suggesting that drug and the solvent system facilitates the micellization process. In addition, the transport properties were examined by employing controlled approaches likely, apparent molar volume (ϕ v ), apparent molar adiabatic compression (ϕ k ), and isentropic compression (κ s ) of SDS in presence of FLZ. These parameters revealed the existence of intermolecular interactions within the molecules. Therefore, this study would cast light on utilizing surfactant immobilized FLZ system for better topical biological action

Survey of chemical compounds tested in vitro against rumen protozoa for possible control of bloat.

Science.gov (United States)

Willard, F L; Kodras, R

1967-09-01

Over 170 chemical agents were screened for antiprotozoal action in bovine ruminal fluid. Compounds were tested at 0.1 and 0.05% concentrations. Tested compounds included inorganic compounds, antibiotics, biocides, neuromuscular agents, arsenicals, plant and animal hormones, antimalarials, surface-active agents, anthelmintics, and many others. The most active compounds were cupric sulfate, nickel sulfate, nitrofurazone, hydrogen peroxide, dodecyl sodium sulfate, pelargonic acid, iodoacetic acid, 1-diethylaminoethylamino-4-methylthiaxanthrone, sodium arsanilate, sodium arsenate, bismuth glycolyl arsanilate, 1-beta-hydroxyethyl-2-methyl-5-nitroimidazole, and p-nitroaniline. Copper ion was not particularly effective against entodinia; nickel ion had no effect on holotrichs. Hydrogen peroxide and iodoacetic acid were effective at a concentration of 0.005%. Anionic surface-active agents were very effective, especially long-chain sulfates and phosphates. These antiprotozoal agents warrant further in vivo studies for possible use in treating or curing bloat in ruminants.

Reaction of Hydrogen Chloride Gas with Sodium Carbonate and Its Deep Removal in a Fixed-Bed Reactor

Czech Academy of Sciences Publication Activity Database

Hartman, Miloslav; Svoboda, Karel; Pohořelý, Michael; Šyc, Michal; Chen, Po-Ch.

2014-01-01

Roč. 53, č. 49 (2014), s. 19145-19158 ISSN 0888-5885 R&D Projects: GA ČR GC14-09692J Grant - others:NSC(TW) 102WBS0300011 Institutional support: RVO:67985858 Keywords : hot fuel gas purification * hydrogen chloride gas * active sodium carbonate Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.587, year: 2014

Ni-polymer nanogel hybrid particles: A new strategy for hydrogen production from the hydrolysis of dimethylamine-borane and sodium borohydride

International Nuclear Information System (INIS)

Cai, Haokun; Liu, Liping; Chen, Qiang; Lu, Ping; Dong, Jian

2016-01-01

Efficient non-precious metal catalysts are crucial for hydrogen production from borohydride compounds in aqueous media via hydrogen atoms in water. A method for preparing magnetic polymer nanoparticles is developed in this study based on the chemical deposition of nickel onto hydrophilic polymer nanogels. High-resolution transmission electron microscopic and XPS analyses show that Ni exists mainly in the form of NiO in nanogels. Excellent catalytic activities of the nanoparticles are demonstrated for hydrogen generation from the hydrolysis of dimethylamine-borane and sodium borohydride in which the initial TOF (turn-over frequencies) are 376 and 1919 h"−"1, respectively. Kinetic studies also reveal an Arrhenius activation energy of 50.96 kJ mol"−"1 for the hydrolysis of dimethylamine-borane and 47.82 kJ mol"−"1 for the hydrolysis of sodium borohydride, which are lower than those catalyzed by Ru metal. Excellent reusability and the use of water for hydrogen production from dimethylamine-borane provide the additional benefit of using a hybrid catalyst. The principle illustrated in the present study offers a new strategy to explore polymer-transition metal hybrid particles for hydrogen energy technology. - Highlights: • Electroless Ni plating on polymer nanogels generated recyclable catalysts. • The Ni particles proved efficient for H_2 production from borohydride compounds. • The catalysts have lower activation energies than Ru for the hydrolysis. • Borohydride hydrolysis is more beneficial than dehydrogenation in organic solvent.

Hg/HgO electrode and hydrogen evolution potentials in aqueous sodium hydroxide

Energy Technology Data Exchange (ETDEWEB)

Nickell, Ryan A.; Zhu, Wenhua H.; Payne, Robert U.; Cahela, Donald R.; Tatarchuk, Bruce J. [Center for Microfibrous Materials Manufacturing, Department of Chemical Engineering, 230 Ross Hall, Auburn University, Auburn, AL 36849 (United States)

2006-10-27

The Hg/HgO electrode is usually utilized as a reference electrode in alkaline solution such as for development of an alkaline hydrogen electrode. The reference electrode provides a suitable reference point but is available from few commercial vendors and suffers from inadequate documentation on potential in varying electrolytes. A new numerical method uses activity, activity coefficients, and a few correlated empirical equations to determine the potential values in both dilute and concentrated sodium hydroxide solutions at temperatures of 0-90{sup o}C and at concentrations of 0.100-12.8mol kg{sub H{sub 2}O}{sup -1}. The computed potentials of the Hg/HgO electrodes versus a normal hydrogen electrode (NHE) at 25{sup o}C and 1atm are 0.1634V for 0.100m, 0.1077V for 1.00m, and 0.0976V for 1.45m NaOH solutions. The Hg/HgO reduction potential further changes to -0.0751V versus NHE and hydrogen evolution potential changes to -0.9916V versus NHE in a solution of 30.0wt.% NaOH at 80{sup o}C. The calculated values are compared with the measured data at 25 and 75{sup o}C. The experimental data agree well with the numerical values computed from the theoretical and empirical equations. (author)

Examination of dexamethasone sodium sulfate and hyperbaric oxygenation in experimentally produced cerebral edema. With special reference to their combination

Energy Technology Data Exchange (ETDEWEB)

Kanaya, H; Onodera, H; Watanabe, M; Kamata, K [Iwate Medical Coll., Morioka (Japan). School of Medicine

1975-06-01

Dexamethasone sodium sulfate and hyperbaric oxygenation were used for experimentally produced cerebral edema for the examination of the water content of the brain and cerebrovascular permeability using /sup 203/Hg as the tracer. Although dexamethasone starts lowering vascular permeability of the edematous brain at one hour after the intravenous injection, a lapse of 24 hours is required until the water content returns to normal. Although hyperbaric oxygenation dose not reduce cerebrovascular permeability, it brings back the water content of the brain to normal immediately after pressurization. Since the combination of dexamethasone and hyperbaric oxygenation maintains the water content of the brain almost normal throughout the entire process, it is ideal for the treatment of cerebral edema.

Computer analysis of sodium cold trap design and performance

International Nuclear Information System (INIS)

McPheeters, C.C.; Raue, D.J.

1983-11-01

Normal steam-side corrosion of steam-generator tubes in Liquid Metal Fast Breeder Reactors (LMFBRs) results in liberation of hydrogen, and most of this hydrogen diffuses through the tubes into the heat-transfer sodium and must be removed by the purification system. Cold traps are normally used to purify sodium, and they operate by cooling the sodium to temperatures near the melting point, where soluble impurities including hydrogen and oxygen precipitate as NaH and Na 2 O, respectively. A computer model was developed to simulate the processes that occur in sodium cold traps. The Model for Analyzing Sodium Cold Traps (MASCOT) simulates any desired configuration of mesh arrangements and dimensions and calculates pressure drops and flow distributions, temperature profiles, impurity concentration profiles, and impurity mass distributions

Steam generators of Phenix: Measurement of the hydrogen concentration in sodium for detecting water leaks in the steam generator tubes; Generateurs de vapeur de Phenix-mesure de la concentration d'hydrogene du sodium pour la surveillance de l'etancheite des tubes d'eau-vapeur

Energy Technology Data Exchange (ETDEWEB)

Cambillard, E; Lacroix, A; Langlois, J; Viala, J

1975-07-01

The Phenix secondary circuits are provided with measurement systems of hydrogen concentration in sodium, that allow for the detection of possible water leaks in steam generators and the location of a faulty module. A measurement device consists of : a detector with nickel membranes of 0, 3 mm wall thickness, an ion pump with a 200 l/s flow rate, a quadrupole mass spectrometer and a calibrated hydrogen leak. The temperature correction is made automatically. The main tests carried out on the leak detection systems are reported. Since the first system operation (October 24, 1973), the measurements allowed us to obtain the hydrogen diffusion rates through the steam generator tube walls. (author)

Kinetics and mechanism of the furan peroxide formation in the reaction of furfural with hydrogen peroxide in the presence and absence of sodium molybdate

International Nuclear Information System (INIS)

Grunskaya, E.P.; Badovskaya, L.A.; Kaklyugina, T.Ya.; Poskonin, V.V.

2000-01-01

Kinetics of the initial stage of the reaction of furfural with hydrogen peroxide are studied in the presence of Na 2 MoO 4 in water and without catalytic additions in n-butanol. Organic peroxide having in its disposal Mo(6), which is the only product on the initial stage of the reaction, is formed since the first minutes of oxidation of furfural by hydrogen peroxide with the presence of Na 2 MoO 4 . The mechanisms of conversion of furfural in the Na 2 MoO 4 - H 2 O system and its oxidation by peroxide without sodium molybdate are discussed. Schemes of formation of furfural complexes based on the results of kinetic studies are suggested. Comparison of obtained data demonstrates that presence of the sodium molybdates in the reaction medium trends to change of reaction procedure in the hydrogen peroxide [ru

AC impedance spectroscopy study of the corrosion behavior of an AZ91 magnesium alloy in 0.1 M sodium sulfate solution

International Nuclear Information System (INIS)

Chen, Jian; Wang, Jianqiu; Han, Enhou; Dong, Junhua; Ke, Wei

2007-01-01

The corrosion behavior of an AZ91 magnesium alloy in 0.1 M sodium sulfate solution at the corrosion potential (E corr ) was investigated using electrochemical impedance spectroscopy (EIS), environmental scanning electron microscopy (ESEM), energy dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). The results showed that when the immersion time was less than 18th, general corrosion occurred on the surface and the main corrosion products were hydroxides and sulfates. The film coverage effect was the main mechanism for the corrosion process of AZ91 alloy. At this stage, the matrix had a better corrosion resistance. With the increasing immersion time, pitting occurred on the surface. At this stage, the corrosion process was controlled by three surface state variables: the area fraction θ 1 of the region controlled by the formation of Mg(OH) 2 , the area fraction θ 2 of the region controlled by the precipitation of MgAl 2 (SO 4 ) 4 .2H 2 O, and the metastable Mg + concentration C m

Effect of sodium borohydride synthesis on NaBH4-H2 system economics

International Nuclear Information System (INIS)

Tabakoglu, F. oeznur; Kurtulus, Guelbahar

2007-01-01

The hazards and negative impacts of fossil fuel usage on environment and the prospect of fossil fuel depletion in near future have urged scientists to search for and use clean energy sources and alternative fuels. Hydrogen is the best fuel among others, which can minimize the effects of global warming. Although it is currently more expensive than other fuels, it will be cheaper following further developments in hydrogen technologies from production till end-use. Hydrogen storage is a critical issue in terms of safety and economics of hydrogen energy system. Chemical hydrides are an attractive hydrogen storage method due to their potential of achieving high volumetric and gravimetric storage densities. Among chemical hydrides, sodium borohydride (NaBH 4 ) is given a big attention, due to its 10.8% theoretical hydrogen storage capacity. Hydrogen, which can be released by sodium borohydride hydrolysis reaction on-site, can be used in a proton exchange membrane fuel cell (PEMFC) at anode. on the other hand, sodium borohydride solution can be used directly in a borohydride fuel cell (DBFC) at anode. Like the other chemical hydrides, sodium borohydride has been an expensive material up to now, constituting a major obstacle to commercialization of sodium borohydride as a hydrogen storage method. This paper aims to give an approximate estimation process cost of the NaBH 4 -H 2 system by taking into account both the energy and raw material costs, starting with sodium borohydride production till recycling of it. Two different methods to synthesize sodium borohydride are analyzed and their effects on total cost are compared. It was found that the usage of Bayer process to synthesize sodium borohydride makes the overall sodium borohydride - hydrogen system cost higher than the total cost of the alternative process which starts with the production of sodium borohydride from borax decahydrate. (authors)

Protective Effect of Daikenchuto on Dextran Sulfate Sodium-Induced Colitis in Mice

Directory of Open Access Journals (Sweden)

Takaharu Matsunaga

2017-01-01

Full Text Available Aim. To investigate the effect of daikenchuto (TJ-100; DKT for ulcerative colitis (UC model mouse and assess its anti-inflammatory mechanisms. Methods. We evaluated the effects of DKT on dextran sulfate sodium- (DSS- induced experimental colitis. First, we assessed the short-term effects of DKT using two groups: 5% DSS group and 5% DSS with DKT group. Colon length; histological scores; and interleukin- (IL- 10, IL-1β, and tumor necrosis factor-α mRNA expression profiles were analyzed using real-time PCR. Second, we assessed the long-term effects of DKT, by comparing survival time between 2% DSS and 2% DSS with DKT groups. Results. After 7 days, the colon lengths of DSS + DKT group were longer than those of the DSS group (mean values: 6.11 versus 5.69 cm, p<0.05. Furthermore, compared to DSS group, the DSS + DKT group maintained significantly higher levels of serum hemoglobin (13.1 versus 10.7 g/dL, p<0.05 and exhibited significantly higher expression levels of IL-10 (p<0.05. The 2% DSS + DKT group exhibited significantly longer survival time than the 2% DSS group (70 versus 44 days, p<0.01. Conclusion. Our results indicate that DKT prevented inflammation in the colon, indicating its potential as a new therapeutic agent for UC.

Steam generators of Phenix: Measurement of the hydrogen concentration in sodium for detecting water leaks in the steam generator tubes

International Nuclear Information System (INIS)

Cambillard, E.; Lacroix, A.; Langlois, J.; Viala, J.

1975-01-01

The Phenix secondary circuits are provided with measurement systems of hydrogen concentration in sodium, that allow for the detection of possible water leaks in steam generators and the location of a faulty module. A measurement device consists of : a detector with nickel membranes of 0, 3 mm wall thickness, an ion pump with a 200 l/s flow rate, a quadrupole mass spectrometer and a calibrated hydrogen leak. The temperature correction is made automatically. The main tests carried out on the leak detection systems are reported. Since the first system operation (October 24, 1973), the measurements allowed us to obtain the hydrogen diffusion rates through the steam generator tube walls. (author)

Sodium lauryl sulfate impedes drug release from zinc-crosslinked alginate beads: switching from enteric coating release into biphasic profiles.

Science.gov (United States)

Taha, Mutasem O; Nasser, Wissam; Ardakani, Adel; Alkhatib, Hatim S

2008-02-28

The aim of this research is to investigate the effects of sodium lauryl sulfate (SLS) on ionotropically cross-linked alginate beads. Different levels of SLS were mixed with sodium alginate and chlorpheniramine maleate (as loaded model drug). The resulting viscous solutions were dropped onto aqueous solutions of zinc or calcium ions for ionotropic curing. The generated beads were assessed by their drug releasing profiles, infrared and differential scanning colorimetery (DSC) traits. SLS was found to exert profound concentration-dependent impacts on the characteristics of zinc-crosslinked alginate beads such that moderate modifications in the levels of SLS switched drug release from enteric coating-like behavior to a biphasic release modifiable to sustained-release by the addition of minute amounts of xanthan gum. Calcium cross-linking failed to reproduce the same behavior, probably due to the mainly ionic nature of calcium-carboxylate bonds compared to the coordinate character of their zinc-carboxylate counterparts. Apparently, moderate levels of SLS repel water penetration into the beads, and therefore minimize chlorpheniramine release. However, higher SLS levels seem to discourage polymeric cross-linking and therefore allow biphasic drug release.

Methanogenic archaea and sulfate reducing bacteria co-cultured on acetate: teamwork or coexistence?

Science.gov (United States)

Ozuolmez, Derya; Na, Hyunsoo; Lever, Mark A; Kjeldsen, Kasper U; Jørgensen, Bo B; Plugge, Caroline M

2015-01-01

Acetate is a major product of fermentation processes and an important substrate for sulfate reducing bacteria and methanogenic archaea. Most studies on acetate catabolism by sulfate reducers and methanogens have used pure cultures. Less is known about acetate conversion by mixed pure cultures and the interactions between both groups. We tested interspecies hydrogen transfer and coexistence between marine methanogens and sulfate reducers using mixed pure cultures of two types of microorganisms. First, Desulfovibrio vulgaris subsp. vulgaris (DSM 1744), a hydrogenotrophic sulfate reducer, was cocultured together with the obligate aceticlastic methanogen Methanosaeta concilii using acetate as carbon and energy source. Next, Methanococcus maripaludis S2, an obligate H2- and formate-utilizing methanogen, was used as a partner organism to M. concilii in the presence of acetate. Finally, we performed a coexistence experiment between M. concilii and an acetotrophic sulfate reducer Desulfobacter latus AcSR2. Our results showed that D. vulgaris was able to reduce sulfate and grow from hydrogen leaked by M. concilii. In the other coculture, M. maripaludis was sustained by hydrogen leaked by M. concilii as revealed by qPCR. The growth of the two aceticlastic microbes indicated co-existence rather than competition. Altogether, our results indicate that H2 leaking from M. concilii could be used by efficient H2-scavengers. This metabolic trait, revealed from coculture studies, brings new insight to the metabolic flexibility of methanogens and sulfate reducers residing in marine environments in response to changing environmental conditions and community compositions. Using dedicated physiological studies we were able to unravel the occurrence of less obvious interactions between marine methanogens and sulfate-reducing bacteria.

Methanogenic archaea and sulfate reducing bacteria co-cultured on acetate: teamwork or coexistence?

Directory of Open Access Journals (Sweden)

Derya eOzuolmez

2015-05-01

Full Text Available Acetate is a major product of fermentation processes and an important substrate for sulfate reducing bacteria and methanogenic archaea. Most studies on acetate catabolism by sulfate reducers and methanogens have used pure cultures. Less is known about acetate conversion by mixed pure cultures and the interactions between both groups. We tested interspecies hydrogen transfer and coexistence between marine methanogens and sulfate reducers using mixed pure cultures of two types of microorganisms. First, Desulfovibrio vulgaris subsp. vulgaris (DSM 1744, a hydrogenotrophic sulfate reducer, was cocultured together with the obligate aceticlastic methanogen Methanosaeta concilii using acetate as carbon and energy source. Next, Methanococcus maripaludis S2, an obligate H2- and formate-utilizing methanogen, was used as a partner organism to M. concilii in the presence of acetate. Finally, we performed a coexistence experiment between M. concilii and an acetotrophic sulfate reducer Desulfobacter latus AcSR2. Our results showed that D. vulgaris was able to reduce sulfate and grow from hydrogen leaked by M. concilii. In the other coculture, M. maripaludis was sustained by hydrogen leaked by M. concilii as revealed by qPCR. The growth of the two aceticlastic microbes indicated co-existence rather than competition. Altogether, our results indicate that H2 leaking from M. concilii could be used by efficient H2-scavengers. This metabolic trait, revealed from coculture studies, brings new insight to the metabolic flexibility of methanogens and sulfate reducers residing in marine environments in response to changing environmental conditions and community compositions. Using dedicated physiological studies we were able to unravel the occurrence of less obvious interactions between marine methanogens and sulfate-reducing bacteria.

Enhanced removal of detergent and recovery of enzymatic activity following sodium dodecyl sulfate-polyacrylamide gel electrophoresis: UUse of casein in gel wash buffer

International Nuclear Information System (INIS)

McGrew, B.R.; Green, D.M.

1990-01-01

The inclusion of 1% casein or bovine serum albumin in buffer used to reactivate enzymes subjected to sodium dodecyl sulfate (SDS)-polyacrylamide electrophoresis resulted in accelerated removal of SDS and restoration of nuclease and beta-galactosidase enzyme activities. Nuclease and beta-galactosidase activities which are absent from gels after longer wash procedures are detectable with this technique. Enzyme activity in gels prepared with SDS which contained inhibitory contaminants was partially restored by the casein wash procedure. The threshold of detection of two-dimensionally separated deoxyribonuclease I using the casein wash procedure was 1 picogram

Polycation-sodium lauryl ether sulfate-type surfactant complexes: influence of ethylene oxide length.

Science.gov (United States)

Vleugels, Leo F W; Pollet, Jennifer; Tuinier, Remco

2015-05-21

Polyelectrolyte-surfactant complexes (PESC) are a class of materials which form spontaneously by self-assembly driven by electrostatic and hydrophobic interactions. PESC containing sodium lauryl ether sulfates (SLES) have found wide application in hair care products like shampoo. Typically, SLES with only one or two ethylene oxide (EO) groups are used for this application. We have studied the influence of the size of the EO block (ranging from 0 to 30 EO groups) on complexation with two model polycations: linear polyDADMAC and branched PEI. PESC size and electrostatic properties were determined during stepwise titration of buffered polycation solutions. The critical aggregation concentration (CAC) of PESC was determined by surface tension measurements and fluorescence spectroscopy. For polyDADMAC, there is no influence of the size of the EO block on the complexation behavior; the stiff polycation governs the structure formation. For PEI, it was seen that the EO block size does affect the structure of the complexes. The CAC value of the investigated complexes turns out to be rather independent of the EO block size; however, the CMC/CAC ratio decreases with increasing size of the EO block. This latter observation explains why the Lochhead-Goddard effect is most effective for small EO blocks.

Application and Mechanism of Anionic Collector Sodium Dodecyl Sulfate (SDS in Phosphate Beneficiation

Directory of Open Access Journals (Sweden)

Kun Sun

2017-02-01

Full Text Available Phosphate ore is a valuable strategic resource. Most phosphate ore in China is collophane. Utilization of mid-low grade collophane is necessary to maintain social sustainable development. The gravity-flotation combination separation process can be utilized to separate mid-low grade collophane, but the process consumes a large quantity of acid in the reverse stage. Sodium dodecyl sulfate (SDS was used as a dolomite collector in this study to reduce the acid consumption of collophane flotation. SDS effectively removed dolomite from the gravity concentrate when no other reagents were present. Flotation test results showed that, compared to the conventional gravity-flotation process, the proposed SDS-based process reduced phosphoric acid dosage from 6.1 kg/t to 3.9 kg/t with similar separation results. The SDS action mechanisms on dolomite were further investigated by zeta potential analysis, single mineral flotation tests, infrared spectrum detection, and theoretical analysis. The results indicate that the SDS adsorption on dolomite is mainly physical adsorption, and that favorable separation effects between collophane and dolomite may be attributed to physical adsorption and entrainment. In addition, it also indicates that the physical adsorption can be utilized to remove dolomite from phosphate on account of zeta potential differences when the separate feed is coarse.

Management of stomal varices with transvenous obliteration utilizing sodium tetradecyl sulfate foam sclerosis.

Science.gov (United States)

Saad, Wael E A; Schwaner, Sandra; Lippert, Allison; Sabri, Saher S; Al-Osaimi, Abdullah; Matsumoto, Alan H; Angle, John F; Caldwell, Stephen

2014-12-01

The management of parastomal varices is not established. Transjugular intrahepatic portosystemic shunt (TIPS) creation is the most commonly described treatment; however, the rebleed rate after TIPS is 21-37%. The purpose of the study is to determine the effectiveness of transvenous obliteration using sodium tetradecyl sulfate (STS) and to describe a new simplified technique in obliterating these varices. Four patients are presented who underwent transvenous obliteration using STS. One was obliterated using balloon occlusion from the systemic veins, the second was obliterated without balloon from a transhepatic antegrade approach, and the last two patients were obliterated using the direct antegrade technique. This simplified technique requires only a micropuncture kit (not requiring balloons or coils) and ultrasound transducer compression of the systemic draining veins, relying on high portal pressure to keep the sclerosant confined to the varices. The sclerosant is essentially trapped between the portal pressure and the ultrasound-transducer compression (10-15 min). Technical success was achieved in all four patients without procedural or postprocedural complications and no rebleeding for a mean follow-up of 17 (range 2-33) months. Transvenous obliteration of parastomal varices utilizing STS as a sclerosant is safe and effective. The newly described technique is simple, feasible, and requires minimal equipment (no balloons or coils or catheters).

The effect of caffeine on the reactions of the excited singlet state of pyrene in micellar sodium lauryl sulfate

Science.gov (United States)

Hashimoto, Shuichi; Thomas, J. Kerry

1984-08-01

The effect of caffeine on a few photo-induced reactions of pyrene in micellar sodium lauryl sulfate (NaLS) has been studied. In these systems caffeine complexes with the pyrene (K asso = 85 ± 10 M -1 and also with the other reactants, e.g. Cu 2+ or TI +. The efficiencies of reactions which involve contact, i.e. pyrene excimer formation, and quenching by TI + ions to give the triplet state of pyrene, are significantly reduced in the presence of caffeine, due to geometric inhibitions formed by the complexation processes. The kinetics of photo-induced electron transfer, e.g. between excited pyrene and Cu 2+, are not affected. However, the subsequent reactions of the products are modified and the yield of ionic products is markedly increased.

Dispersive admicelle solid-phase extraction based on sodium dodecyl sulfate coated Fe3 O4 nanoparticles for the selective adsorption of three alkaloids in Gegen-Qinlian oral liquid before high-performance liquid chromatography.

Science.gov (United States)

Shi, Zhihong; Xu, Dan; Zhao, Xuan; Li, Xinghong; Shen, Huimin; Yang, Bing; Zhang, Hongyi

2017-12-01

A novel dispersive admicelle solid-phase extraction method based on sodium dodecyl sulfate-coated Fe 3 O 4 nanoparticles was developed for the selective adsorption of berberine, coptisine, and palmatine in Gegen-Qinlian oral liquid before high-performance liquid chromatography. Fe 3 O 4 nanoparticles were synthesized by a chemical coprecipitation method and characterized by using transmission electron microscopy. Under acidic conditions, the surface of Fe 3 O 4 nanoparticles was coated with sodium dodecyl sulfate to form a nano-sized admicelle magnetic sorbent. Owing to electrostatic interaction, the alkaloids were adsorbed onto the oppositely charged admicelle magnetic nanoparticles. The quick separation of the analyte-adsorbed nanoparticles from the sample solution was performed by using Nd-Fe-B magnet. Best extraction efficiency was achieved under the following conditions: 800 μL Fe 3 O 4 nanoparticles suspension (20 mg/mL), 150 μL sodium dodecyl sulfate solution (10 mg/mL), pH 2, and vortexing time 2 min for the extraction of alkaloids from 10 mL of diluted sample. Four hundred microliters of methanol was used to desorb the alkaloids by vortexing for 1 min. Satisfactory extraction recoveries were obtained in the range of 85.9-120.3%, relative standard deviations for intra- and interday precisions were less than 6.3 and 10.0%, respectively. Finally, the established method was successfully applied to analyze the alkaloids in two batches of Gegen-Qinlian oral liquids. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of 12-O-tetradecanoyl-phorbol-13-acetate [corrected] and sodium lauryl sulfate on the production and expression of cytokines and proto-oncogenes in photoaged and intrinsically aged human keratinocytes.

Science.gov (United States)

Suh, D H; Youn, J I; Eun, H C

2001-11-01

Skin aging may be divided into photoaging and intrinsic aging. The purpose of this study was to investigate the effects of 12-O-tetradecanoyl-phorbol-13-acetate and sodium lauryl sulfate on the production and expression of cytokines and proto-oncogenes in photoaged and intrinsically aged skin, compared with young skin. Keratinocytes were taken from newborns, young adults in their twenties, and from the forearm and thigh of volunteers in their fifties and seventies. Interleukin-1alpha and -6, and interleukin-1 receptor antagonist, c-fos and c-myc were measured after cultured keratinocytes had been treated with 12-O-tetradecanoyl-phorbol-13-acetate and sodium lauryl sulfate. There has been no report concerning the dependence of cytokine production by sodium lauryl sulfate upon photoaging and intrinsic aging. This study also involves the first investigation of the effects of aging on c-myc expression by 12-O-tetradecanoyl-phorbol-13-acetate treatment. Cytokine production decreased markedly with age. These results suggest the progressive decline of cellular function with age. The ratio of cytokine production in the irritant-treated group compared with that in the control group showed a different pattern in photoaging and intrinsic aging. With the significant difference between photoaging and intrinsic aging, T/C ratio decreased in interleukin-1alpha and interleukin-1 receptor antagonist upon aging, whereas it increased in interleukin-6. S/C ratio was uniquely elevated on photoaged skin in the 50 y age group. It is suggested that photoaged skin shows an exaggerated reaction to surfactant. Compared with the control, c-fos expression in 12-O-tetradecanoyl-phorbol-13-acetate-treated keratinocytes decreased with age in the thigh, but increased in the photoaged skin of forearm. The increased c-fos expression in 12-O-tetradecanoyl-phorbol-13-acetate-treated keratinocytes could be relevant for the predisposition of photoaged keratinocytes to malignant transformation.

Usefulness of addition of Orvus ES paste and sodium lauryl sulfate to frozen feline semen.

Science.gov (United States)

Mizutani, Tatsuji; Sumigama, Shiho; Nagakubo, Keiichi; Shimizu, Noriko; Oba, Hiromichi; Hori, Tatsuya; Tsutsui, Toshihiko

2010-01-01

It has been shown that addition of the surfactant Orvus ES paste (OEP) and its main component sodium lauryl sulfate (SLS) to boar or dog semen before freezing improves post-thaw sperm motility and protects acrosome caps. In this study, we investigated the usefulness of the addition of OEP (0, 1, 2 and 4%) or SLS (0, 1, 2, 3 and 4 mg/ml) to cat ejaculates before freezing and their concentrations. Among the OEP addition groups, the 1% OEP group showed higher sperm motility than the other groups. Among the SLS addition groups, the 3 mg/ml SLS group showed slightly higher sperm motility and viability than the other groups. Comparison between the 1% OEP and 3 mg/ml SLS addition groups suggested a higher percentage of sperm with an acrosome cap in the 1% OEP group. The other sperm properties did not significantly differ between the 2 groups. These results indicate that addition of 1% OEP or 3 mg/ml SLS is effective for freezing of cat ejaculated semen.

Fabrication and surface properties of hydrophobic barium sulfate aggregates based on sodium cocoate modification

Science.gov (United States)

Hu, Linna; Wang, Guangxiu; Cao, Rong; Yang, Chun; Chen, Xi

2014-10-01

Hydrophobic barium sulfate aggregates were fabricated by the direction of cocoate anions. At 30 °C, when the weight ratio of sodium cocoate to BaSO4 particles was 2.0 wt.%, the active ratio of the product reached 99.43% and the contact angle was greater than 120°. This method could not only simplify the complex modification process, but reduce energy consumption. The surface morphology, chemical structure and composition of BaSO4 aggregates were characterized by SEM, XRD, and FTIR. The results indicated that the as-synthesized BaSO4 particles were almond-liked and were composed of many interconnected nanoballs and that their surfaces were affected by cocoate anions. The adsorption of cocoate anions reversed the charge and weakened the surface polarity of BaSO4 particles, driving the formation of aggregates. And cocoate anions induced a change of the BaSO4 particles surface from hydrophilic to hydrophobic by a self-assembly and transformation process. Due to the self-assembled structure and the surface hydrophobicity, when adding the hydrophobic BaSO4 into PVC, the mechanical properties of PVC composite materials were significantly improved.

Application of Biostimulation for Remediation of Sulfate-Contaminated Groundwater at a Mining Site

Science.gov (United States)

Miao, Z.; Carroll, K. C.; Carreon, C.; Brusseau, M. L.

2011-12-01

There is growing concern regarding sulfate contamination of groundwater. One innovative in-situ remediation option under investigation is biostimulation through addition of electron-donor amendments to enhance sulfate reduction. Two pilot-scale ethanol-injection tests were conducted at a former uranium mining site that is contaminated with sulfate and nitrate (with a lack of heavy metals), and for which there appears to be minimal natural attenuation of sulfate. The first test was a push-pull test that had a limited zone of influence, while the second test was a single-well injection test in which additional downgradient wells were monitored. For both tests, sulfate concentrations began to decline within a few weeks of injection, after nitrate concentrations were significantly reduced. Concomitantly, aqueous concentrations of manganese, iron, and hydrogen sulfide increased from background. Monitoring over many months revealed that the declines in sulfate concentration conformed to exponential decay, with first-order decay rates of approximately 0.01 /d. Analysis of sulfur stable isotope data indicated that the decrease in sulfate concentrations was microbially mediated. The results also indicated that sulfides formed during sulfate reduction may have undergone partial re-oxidation. This study illustrates the feasibility of using ethanol injection for remediation of sulfate-contaminated groundwater. However, re-oxidation of sulfides (both metal sulfide precipitates and hydrogen sulfide gas) is a potential issue of significance that would need to be addressed.

Sustained release of simvastatin from hollow carbonated hydroxyapatite microspheres prepared by aspartic acid and sodium dodecyl sulfate.

Science.gov (United States)

Wang, Ke; Wang, Yinjing; Zhao, Xu; Li, Yi; Yang, Tao; Zhang, Xue; Wu, Xiaoguang

2017-06-01

Hollow carbonated hydroxyapatite (HCHAp) microspheres as simvastatin (SV) sustained-release vehicles were fabricated through a novel and simple one-step biomimetic strategy. Firstly, hollow CaCO 3 microspheres were precipitated through the reaction of CaCl 2 with Na 2 CO 3 in the presence of aspartic acid and sodium dodecyl sulfate. Then, the as-prepared hollow CaCO 3 microspheres were transformed into HCHAp microspheres with a controlled anion-exchange method. The HCHAp microspheres were 3-5μm with a shell thickness of 0.5-1μm and were constructed of short needle nanoparticles. The HCHAp microspheres were then loaded with SV, exhibiting excellent drug-loading capacity and sustained release properties. These results present a new material synthesis strategy for HCHAp microspheres and suggest that the as-prepared HCHAp microspheres are promising for applications in drug delivery. Copyright © 2017 Elsevier B.V. All rights reserved.

Plutonium oxides analysis. Sulfur potentiometric analysis

International Nuclear Information System (INIS)

Anon.

Total sulfur determination (sulfur, sulfates, sulfides ...) in plutonium oxides, suitable for sulfate ion content between 0.003 percent to 0.2 percent, by dissolution in nitric hydrofluoric acid, nitrates elimination, addition of hydrochloric acid and reduction in hydrogen sulfide which is carried by an inert gas and neutralized by sodium hydroxide. Sodium sulfide is titrated with mercuric acetate by constant intensity potentiometry [fr

Methods for the sodium cooled fast reactor fire safety provisions

International Nuclear Information System (INIS)

Gryaznov, B.V.; Dergachev, N.P.

1983-01-01

Problems of fire safety provision on NPPs with sodium cooled fast reactor are under discussion. Methods of sodium leak localization, measures eliminating sodium flaring up during leaks and main means of sodium fire extinguishing are considered. An extinguishing of sodium flaring up is performed by means of sodium temperatUre decrease and by limitation of hydrogen access to the flaring up surface. A conclusion is made that the most effective methods of extinguishing are the following: self-extinguishing (due to hydrogen burning out in a limiting volume); extinguishing by a gas mixture of nitrogen and carbonic acid (initial filling and blowing of rooms during sodium flaring up); extinguishing by special powders

Reactions of solid CaSO{sub 4} and Na{sub 2}CO{sub 3} and formation of sodium carbonate sulfate double salts

Energy Technology Data Exchange (ETDEWEB)

Wang, Jinsheng; Wu, Yinghai; Anthony, Edward J. [CANMET Energy Technology Centre, Natural Resources Canada, 1 Haanel Dr., Ottawa, Ontario K1A 1M1 (Canada)

2007-07-01

High-temperature chemical reactions in mixtures of solid CaSO{sub 4} and Na{sub 2}CO{sub 3} were investigated in order to explore the mechanisms of enhanced sulfur capture by limestones doped with Na{sub 2}CO{sub 3} in fluidized bed combustion. Drastic weight loss of the mixtures was observed in a thermogravimetric analyzer near the melting temperature of Na{sub 2}CO{sub 3}, indicating chemical reaction. X-ray diffraction analysis for a mixture of the solids following a heat treatment at 850 C revealed the existence of two sodium carbonate sulfate double salts that have not been reported before for the present system. The formation of Na{sub 2}SO{sub 4} in the melt of Na{sub 2}CO{sub 3} appears to precede the formation of the double salts. The two double salts are believed to have high porosity and specific surface area similar to those of a better-known double salt, burkeite. The implications of these findings for the enhancement of limestone sulfation by Na{sub 2}CO{sub 3} are also discussed. (author)

Reactions of solid CaSO{sub 4} and Na{sub 2}CO{sub 3} and formation of sodium carbonate sulfate double salts

Energy Technology Data Exchange (ETDEWEB)

Wang Jinsheng [CANMET Energy Technology Centre, Natural Resources Canada, 1 Haanel Dr., Ottawa, Ontario K1A 1M1 (Canada)]. E-mail: jiwang@nrcan.gc.ca; Wu Yinghai [CANMET Energy Technology Centre, Natural Resources Canada, 1 Haanel Dr., Ottawa, Ontario K1A 1M1 (Canada); Anthony, Edward J. [CANMET Energy Technology Centre, Natural Resources Canada, 1 Haanel Dr., Ottawa, Ontario K1A 1M1 (Canada)

2007-07-01

High-temperature chemical reactions in mixtures of solid CaSO{sub 4} and Na{sub 2}CO{sub 3} were investigated in order to explore the mechanisms of enhanced sulfur capture by limestones doped with Na{sub 2}CO{sub 3} in fluidized bed combustion. Drastic weight loss of the mixtures was observed in a thermogravimetric analyzer near the melting temperature of Na{sub 2}CO{sub 3}, indicating chemical reaction. X-ray diffraction analysis for a mixture of the solids following a heat treatment at 850 deg. C revealed the existence of two sodium carbonate sulfate double salts that have not been reported before for the present system. The formation of Na{sub 2}SO{sub 4} in the melt of Na{sub 2}CO{sub 3} appears to precede the formation of the double salts. The two double salts are believed to have high porosity and specific surface area similar to those of a better-known double salt, burkeite. The implications of these findings for the enhancement of limestone sulfation by Na{sub 2}CO{sub 3} are also discussed.

Infusing Sodium Bicarbonate Suppresses Hydrogen Peroxide Accumulation and Superoxide Dismutase Activity in Hypoxic-Reoxygenated Newborn Piglets

OpenAIRE

Liu, Jiang-Qin; Manouchehri, Namdar; Lee, Tze-Fun; Yao, Mingzhu; Bigam, David L.; Cheung, Po-Yin

2012-01-01

Background The effectiveness of sodium bicarbonate (SB) has recently been questioned although it is often used to correct metabolic acidosis of neonates. The aim of the present study was to examine its effect on hemodynamic changes and hydrogen peroxide (H2O2) generation in the resuscitation of hypoxic newborn animals with severe acidosis. Methods Newborn piglets were block-randomized into a sham-operated control group without hypoxia (n = 6) and two hypoxia-reoxygenation groups (2 h normocap...

Experimental investigations and modelling of sodium-concrete interaction

International Nuclear Information System (INIS)

Schultheiss, G.F.; Deeg, H.J.

1990-01-01

The use of sodium as a coolant in liquid metal fast breeder reactors, fusion reactors, and solar plants requires special consideration of its chemical reactivity and related safety problems in the case of sodium leckage. On contact between hot sodium and concrete an interaction takes place resulting in energy release and hydrogen generation, which may contribute to containment loading by pressurization in a hypothetical accident situation. For this reason, sodium-concrete interactions were investigated experimentally and theoretically. The experiments revealed important effects of quartzitic material within the concrete and of the sodium temperature on the interaction mechanisms, the energy release and the consequent hydrogen production. The numerical model shows good agreement with the experimental results. (orig.) [de

Inflammatory reaction of the anterior dorsal tongue presumably to sodium lauryl sulfate within toothpastes: a triple case report.

Science.gov (United States)

Brown, Ronald S; Smith, Langston; Glascoe, Alison L

2018-02-01

Sodium lauryl sulfate (SLS), a popular surface active agent ingredient within toothpastes, is known for its foaming action. Surface active agents increase the effectiveness of toothpastes with respect to dental plaque removal. SLS is a known irritant and also has allergenic potential. The authors report 3 patients with oral pain secondary to inflammation of the dorsal anterior tongue. These patients were all using toothpastes with SLS as an ingredient. The dorsal tongue lesions and oral pain resolved upon switching to toothpastes without SLS as an ingredient. Clinicians should be aware of the potential of SLS within toothpastes to cause oral mucosal inflammatory reactions of the anterior dorsal tongue. To our knowledge, these are the first case reports of oral mucosal inflammatory reactions of the anterior dorsal tongue associated with SLS containing toothpastes. Copyright © 2017 Elsevier Inc. All rights reserved.

Puberty Is Delayed in Male Mice With Dextran Sodium Sulfate Colitis Out of Proportion to Changes in Food Intake, Body Weight, and Serum Levels of Leptin

OpenAIRE

DEBOER, MARK D.; LI, YONGLI

2011-01-01

In boys, inflammatory bowel disease often results in delayed puberty associated with decreased bone mineral density and decreased linear growth. Our goal was to investigate whether pubertal timing and levels of leptin differed between prepubertal male mice with colitis and food-restricted (FR) mice maintained at a similar weight. We induced colitis in 32-d-old male mice using dextran sodium sulfate (DSS), resulting in 10 d of worsening colitis. We followed up these mice for separation of the ...

Evaluation of sulfate resistance of cement mortars containing black rice husk ash.

Science.gov (United States)

Chatveera, B; Lertwattanaruk, P

2009-03-01

In this paper, black rice husk ashes (BRHAs), which are agrowastes from an electricity generating power plant and a rice mill, were ground and used as a partial cement replacement. The durability of mortars under sulfate attack including expansion and compressive strength loss were investigated. For parametric study, BRHA were used as a Portland cement Type 1 replacement at the levels of 0%, 10%, 30%, and 50% by weight of binder. The water-to-binder ratios were 0.55 and 0.65. For the durability of mortar exposed to sulfate attack, 5% sodium sulfate (Na2SO4) and magnesium sulfate (MgSO4) solutions were used. As a result, when increasing the percentage replacement of BRHA, the expansion and compressive strength loss of mortar decreased. At the replacement levels of 30% and 50% of BRHA, the expansion of the mortars was less than those mixed with sulfate-resistant cement. However, the expansion of the mortars exposed to Na2SO4 was more than those exposed to MgSO4. Increasing the replacement level of BRHA tends to reduce the compressive strength loss of mortars exposed to Na2SO4 attack. In contrary, under MgSO4 attack, when increasing the replacement level of BRHA, the compressive strength loss increases from 0% to 50% in comparison to Portland cement mortar. Results show that ground BRHA can be applied as a pozzolanic material to concrete and also improve resistance to sodium sulfate attack, but it can impair resistance to magnesium sulfate attack.

Thermodynamic selectivity of functional agents on zeolite for sodium dodecyl sulfate sequestration

Energy Technology Data Exchange (ETDEWEB)

Leng, Ling; Wang, Jian [Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR (China); Qiu, Xianxiu; Zhao, Yanxiang; Yip, Yuk-Wang; Law, Ga-Lai [Department of Applied Biology and Chemical Technology, State Key Laboratory of Chirosciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR (China); Shih, Kaimin; Zhou, Zhengyuan [Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, Hong Kong SAR (China); Lee, Po-Heng, E-mail: poheng76@gmail.com [Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR (China)

2016-11-15

Highlights: • A thermodynamic approach to select a functional agent for adsorbent is proposed. • ITC and QCS were used to interpret the interaction between adsorbate and agent. • The interaction identifies the adsorption mechanism and performance. • This approach enables the manipulation of adsorption capacity optimization. - Abstract: This study proposes a thermodynamic approach to effectively select functional agents onto zeolite for sodium dodecyl sulfate (SDS) sequestration in greywater reuse. We combine isothermal titration calorimetry (ITC) and quantum chemistry simulation (QCS) to identify the interactions between SDS and agents at the molecular level. Three potential agents, cetyl trimethyl ammonium bromide (CTAB), N,N,N-trimethyltetradecan-1-aminium bromide (C{sub 14}TAB), and 14-hydroxy-N,N,N-trimethyltetradecan-1-aminium bromide (C{sub 14}HTAB), differ in carbon chain length and hydrophilic groups. The ITC titration of SDS with CTAB released the highest heat, followed by those with C{sub 14}TAB and C{sub 14}HTAB, as was the same trend for the amounts of SDS adsorbed by the respective functionalized-zeolites. Results suggest that the favorable SDS sorption occurred at the bilayer CTAB-zeolite is driven by enthalpy as similar as the SDS…CTAB interaction found, regardless of the contribution from electrostatic and/or hydrophobic behaviors, while the declined sorption is entropy-driven via the predominant hydrophobic interaction onto the monolayer CTAB-zeolite. The data presented here interpret the nature of molecularly thermodynamic quantities and enable the manipulation of sorption capacity optimization.

Nuclear dynamics in the metastable phase of the solid acid caesium hydrogen sulfate.

Science.gov (United States)

Krzystyniak, Maciej; Drużbicki, Kacper; Fernandez-Alonso, Felix

2015-12-14

High-resolution spectroscopic measurements using thermal and epithermal neutrons and first-principles calculations within the framework of density-functional theory are used to investigate the nuclear dynamics of light and heavy species in the metastable phase of caesium hydrogen sulfate. Within the generalised-gradient approximation, extensive calculations show that both 'standard' and 'hard' formulations of the Perdew-Burke-Ernzerhof functional supplemented by Tkatchenko-Scheffler dispersion corrections provide an excellent description of the known structure, underlying vibrational density of states, and nuclear momentum distributions measured at 10 and 300 K. Encouraged by the agreement between experiment and computational predictions, we provide a quantitative appraisal of the quantum contributions to nuclear motions in this solid acid. From this analysis, we find that only the heavier caesium atoms reach the classical limit at room temperature. Contrary to naïve expectation, sulfur exhibits a more pronounced quantum character relative to classical predictions than the lighter oxygen atom. We interpret this hitherto unexplored nuclear quantum effect as arising from the tighter binding environment of this species in this technologically relevant material.

Poly[μ-(1-azaniumylethane-1,1-diyl)- bis(hydrogen phosphonato)sodium]: A powder X-ray diffraction study

International Nuclear Information System (INIS)

Rukiah, M.; Assaad, T.

2015-01-01

The title two-dimensional coordination polymer, [Na(C2H8NO6P2)]n, was characterized using powder X-ray diffraction data and its structure refined using the Rietveld method. The asymmetric unit contains one Na(+) cation and one (1-azaniumylethane-1,1-diyl)bis(hydrogen phosphonate) anion. The central Na(+) cation exhibits distorted octahedral coordination geometry involving two deprotonated O atoms, two hydroxy O atoms and two double-bonded O atoms of the bisphosphonate anion. Pairs of sodium-centred octahedra share edges and the pairs are in turn connected to each other by the biphosphonate anion to form a two-dimensional network parallel to the (001) plane. The polymeric layers are connected by strong O-H...O hydrogen bonding between the hydroxy group and one of the free O atoms of the bisphosphonate anion to generate a three-dimensional network. Further stabilization of the crystal structure is achived by N-H...O and O-H...O hydrogen bonding.(author)

High temperature cathodic charging of hydrogen in zirconium alloys and iron and nickel base alloys

International Nuclear Information System (INIS)

John, J.T.; De, P.K.; Gadiyar, H.S.

1990-01-01

These investigations lead to the development of a new technique for charging hydrogen into metals and alloys. In this technique a mixture of sulfates and bisulfates of sodium and potassium is kept saturated with water at 250-300degC in an open pyrex glass beaker and electrolysed using platinum anode and the material to be charged as the cathode. Most of the studies were carried out on Zr alloys. It is shown that because of the high hydrogen flux available at the surface and the high diffusivity of hydrogen in metals at these temperatures the materials pick up hydrogen faster and more uniformly than the conventional electrolytic charging at room temperature and high temperature autoclaving in LiOH solutions. Chemical analysis, metallographic examination and XRD studies confirm this. This technique has been used to charge hydrogen into many iron and nickel base austentic alloys, which are very resistant to hydrogen pick up and to H-embrittlement. Since this involved a novel method of electrolysing water, the hydrogen/deuterium isotopic ratio has been studied. At this temperatures the D/H ratio in the evolved hydrogen gas was found to be closer to the value in the liquid water, which means a smaller separation factor. This confirm the earlier observation that separation factor decreases with increase of temperature. (author). 16 refs., 21 fi gs., 6 tabs

Hydrogen vacancies facilitate hydrogen transport kinetics in sodium hydride nanocrystallites

NARCIS (Netherlands)

Singh, S.; Eijt, S.W.H.

2008-01-01

We report ab initio calculations based on density-functional theory, of the vacancy-mediated hydrogen migration energy in bulk NaH and near the NaH(001) surface. The estimated rate of the vacancy mediated hydrogen transport, obtained within a hopping diffusion model, is consistent with the reaction

Electrolytic process to produce sodium hypochlorite using sodium ion conductive ceramic membranes

Science.gov (United States)

Balagopal, Shekar; Malhotra, Vinod; Pendleton, Justin; Reid, Kathy Jo

2012-09-18

An electrochemical process for the production of sodium hypochlorite is disclosed. The process may potentially be used to produce sodium hypochlorite from seawater or low purity un-softened or NaCl-based salt solutions. The process utilizes a sodium ion conductive ceramic membrane, such as membranes based on NASICON-type materials, in an electrolytic cell. In the process, water is reduced at a cathode to form hydroxyl ions and hydrogen gas. Chloride ions from a sodium chloride solution are oxidized in the anolyte compartment to produce chlorine gas which reacts with water to produce hypochlorous and hydrochloric acid. Sodium ions are transported from the anolyte compartment to the catholyte compartment across the sodium ion conductive ceramic membrane. Sodium hydroxide is transported from the catholyte compartment to the anolyte compartment to produce sodium hypochlorite within the anolyte compartment.

Human and Environmental Toxicity of Sodium Lauryl Sulfate (SLS): Evidence for Safe Use in Household Cleaning Products.

Science.gov (United States)

Bondi, Cara Am; Marks, Julia L; Wroblewski, Lauren B; Raatikainen, Heidi S; Lenox, Shannon R; Gebhardt, Kay E

2015-01-01

Environmental chemical exposure is a major concern for consumers of packaged goods. The complexity of chemical nomenclature and wide availability of scientific research provide detailed information but lends itself to misinterpretation by the lay person. For the surfactant sodium lauryl sulfate (SLS), this has resulted in a misunderstanding of the environmental health impact of the chemical and statements in the media that are not scientifically supported. This review demonstrates how scientific works can be misinterpreted and used in a manner that was not intended by the authors, while simultaneously providing insight into the true environmental health impact of SLS. SLS is an anionic surfactant commonly used in consumer household cleaning products. For decades, this chemical has been developing a negative reputation with consumers because of inaccurate interpretations of the scientific literature and confusion between SLS and chemicals with similar names. Here, we review the human and environmental toxicity profiles of SLS and demonstrate that it is safe for use in consumer household cleaning products.

Preparation of Lignin/Sodium Dodecyl Sulfate Composite Nanoparticles and Their Application in Pickering Emulsion Template-Based Microencapsulation.

Science.gov (United States)

Pang, Yuxia; Wang, Shengwen; Qiu, Xueqing; Luo, Yanling; Lou, Hongming; Huang, Jinhao

2017-12-20

Lignin is a vastly underutilized biomass resource. The preparation of water-dispersed lignin nanoparticles is an effective way to realize the high-value utilization of lignin. However, the currently reported preparation methods of lignin nanoparticles still have some drawbacks, such as the requirement for toxic organic solvent or chemical modification, complicated operation process, and poor dispersibility. Here, lignin/sodium dodecyl sulfate (SDS) composite nanoparticles (LSNPs) with outstanding water dispersibility and a size range of 70-200 nm were facilely prepared via acidifying the mixed basic solution of alkaline lignin and SDS. No harsh chemical was needed. The formation mechanism was systematically studied. Results indicated that the LSNPs were obtained by acid precipitation of the mixed micelles formed by the self-assembly of lignin and SDS. In addition, on the basis of the LSNP-stabilized Pickering emulsions, lignin/polyurea composite microcapsules combining the excellent chemical stability of a synthetic polyurea shell with the fantastic antiphotolysis and antioxidant properties of lignin were successfully prepared.

Cadmium Immobilization in Soil using Sodium Dodecyl Sulfate Stabilized Magnetite Nanoparticles

Directory of Open Access Journals (Sweden)

Ahmad Farrokhian Firouzi

2017-06-01

Full Text Available Introduction Some methods of contaminated soils remediation reduces the mobile fraction of trace elements, which could contaminate groundwater or be taken up by soil organisms. Cadmium (Cd as a heavy metal has received much attention in the past few decades due to its potential toxic impact on soil organism activity and compositions. Cadmium is a soil pollutant of no known essential biological functions, and may pose threats to soil-dwelling organisms and human health. Soil contamination with Cd usually originates from mining and smelting activities, atmospheric deposition from metallurgical industries, incineration of plastics and batteries, land application of sewage sludge, and burning of fossil fuels. Heavy metal immobilization using amendments is a simple and rapid method for the reduction of heavy metal pollution. One way of the assessment of contaminated soils is sequential extraction procedure. Sequential extraction of heavy metals in soils is an appropriate way to determine soil metal forms including soluble, exchangeable, carbonate, oxides of iron and manganese, and the residual. Its results are valuable in prediction of bioavailability, leaching rate and elements transformation in contaminated agricultural soils. Materials and Methods The objective of this study was to synthesize magnetite nanoparticles (Fe3O4 stabilized with sodium dodecyl sulfate (SDS and to investigate the effect of its different percentages (0, 1, 2.5, 5, and 10% on the different fractions of cadmium in soil by sequential extraction method. The nanoparticles were synthesized following the protocol described by Si et al. (19. The investigations were carried out with a loamy sand topsoil. Before use, the soil was air-dried, homogenized and sieved (

Allicin Alleviates Dextran Sodium Sulfate- (DSS- Induced Ulcerative Colitis in BALB/c Mice

Directory of Open Access Journals (Sweden)

Ashok Kumar Pandurangan

2015-01-01

Full Text Available The objective of this study is to evaluate the effect of allicin (10 mg/kg body weight, orally in an experimental murine model of UC by administering 2.5% dextran sodium sulfate (DSS in drinking water to BALB/c mice. DSS-induced mice presented reduced body weight, which was improved by allicin administration. We noted increases in CD68 expression, myeloperoxidase (MPO activities, and Malonaldehyde (MDA and mRNA levels of proinflammatory cytokines, such as tumor necrosis factor- (TNF- α, interleukin- (IL- 1β, IL-6, and IL-17, and decrease in the activities of enzymic antioxidants such as superoxide dismutase (SOD, Catalase (CAT, Glutathione reductase (GR, and Glutathione peroxidase (GPx in DSS-induced mice. However, allicin treatment significantly decreased CD68, MPO, MDA, and proinflammatory cytokines and increased the enzymic antioxidants significantly (P<0.05. In addition, allicin was capable of reducing the activation and nuclear accumulation of signal transducer and activator of transcription 3 (STAT3, thereby preventing degradation of the inhibitory protein IκB and inducing inhibition of the nuclear translocation of nuclear factor (NF-κB-p65 in the colonic mucosa. These findings suggest that allicin exerts clinically useful anti-inflammatory effects mediated through the suppression of the NF-κB and IL-6/p-STAT3Y705 pathways.

Detoxification of acid pretreated spruce hydrolysates with ferrous sulfate and hydrogen peroxide improves enzymatic hydrolysis and fermentation.

Science.gov (United States)

Soudham, Venkata Prabhakar; Brandberg, Tomas; Mikkola, Jyri-Pekka; Larsson, Christer

2014-08-01

The aim of the present work was to investigate whether a detoxification method already in use during waste water treatment could be functional also for ethanol production based on lignocellulosic substrates. Chemical conditioning of spruce hydrolysate with hydrogen peroxide (H₂O₂) and ferrous sulfate (FeSO₄) was shown to be an efficient strategy to remove significant amounts of inhibitory compounds and, simultaneously, to enhance the enzymatic hydrolysis and fermentability of the substrates. Without treatment, the hydrolysates were hardly fermentable with maximum ethanol concentration below 0.4 g/l. In contrast, treatment by 2.5 mM FeSO₄ and 150 mM H₂O₂ yielded a maximum ethanol concentration of 8.3 g/l. Copyright © 2014 Elsevier Ltd. All rights reserved.

Coprecipitation of rare earths in systems of three heterovalent ions with sulfates of alkali and alkaline-earth metals

International Nuclear Information System (INIS)

Bobrik, V.M.

1977-01-01

Co-precipitation of rare earth elements (REE) in milligram amounts (3x10 -3 -3x10 -1 M) with alkali earth (AEE) sulfates in presence of alkali metal ions has been studied, the AEE:REE ratios between the co-precipitator and a REE (up to 50:1) the latter can be co-precipitated quantitatively in presence of corresponding alkali metals linked with the AEE in the Periodic table by a diagonal, i.e. in presence of sodium in co-precipitation with calcium sulfate, potassium with strontium sulfate and rubidium with barium sulfate. Co-precipitation with sulfates of sodium and calcium occurs at temperatures above 85 deg C and presumably involves calcium semihydrate. In presence of an alkali metal REE co-precipitation with AEE becomes isomorphic, i.e. at different AEE:REE ratios the co-precipitation coefficient remains constant. In presence of corresponding alkali metals the decrease in effectiveness of co-precipitation with AEE in the La-Lu series is more pronounced

A critical evaluation of fasted state simulating gastric fluid (FaSSGF) that contains sodium lauryl sulfate and proposal of a modified recipe.

Science.gov (United States)

Aburub, Aktham; Risley, Donald S; Mishra, Dinesh

2008-01-22

The aim of this work is to evaluate one of the most commonly used fasted state simulating gastric fluids (FaSSGFs), which contains sodium lauryl sulfate (SLS) (FaSSGF(SLS)), and propose a more appropriate surfactant concentration. Surface tension studies clearly show that the critical micelle concentration (CMC) of SLS in the relevant media (a media whose pH and sodium chloride concentration are representative of physiological conditions) is significantly lower (p<0.05) than 8.67 mM, which is the SLS concentration in FaSSGF(SLS). The CMC of SLS in the relevant media was determined to be 1.75 mM. Based on this a modified recipe is proposed in which the concentration of SLS is sufficient to achieve a surface tension similar to that in vivo without causing artificial micellar solubilization. Solubility, intrinsic dissolution, and GastroPlus modeling studies are presented to support and give rationale for the modified recipe. In addition, a comparison between the modified recipe and other FaSSGFs reported in the literature is made.

A comparative study of three cytotoxicity test methods for nanomaterials using sodium lauryl sulfate.

Science.gov (United States)

Kwon, Jae-Sung; Kim, Kwang-Mahn; Kim, Kyoung-Nam

2014-10-01

The biocompatibility evaluation of nanomaterials is essential for their medical diagnostic and therapeutic usage, where a cytotoxicity test is the simplest form of biocompatibility evaluation. Three methods have been commonly used in previous studies for the cytotoxicity testing of nanomaterials: trypan blue exclusion, colorimetric assay using water soluble tetrazolium (WST), and imaging under a microscope following calcein AM/ethidium homodimer-1 staining. However, there has yet to be a study to compare each method. Therefore, in this study three methods were compared using the standard reference material of sodium lauryl sulfate (SLS). Each method of the cytotoxicity test was carried out using mouse fibroblasts of L-929 exposed to different concentrations of SLS. Compared to the gold standard trypan blue exclusion test, both colorimetric assay using water soluble tetrazolium (WST) and imaging under microscope with calcein AM/ethidium homodimer-1 staining showed results that were not statistically different. Also, each method exhibited various advantages and disadvantages, which included the need of equipment, time taken for the experiment, and provision of additional information such as cell morphology. Therefore, this study concludes that all three methods of cytotoxicity testing may be valid, though careful consideration will be needed when selecting tests with regard to time, finances, and the amount of information required by the researcher(s).

SFG and SPR Study of Sodium Dodecyl Sulfate Film Assembly on Positively Charged Surfaces

Science.gov (United States)

Song, Sanghun; Weidner, Tobias; Wagner, Matthew; Castner, David

2012-02-01

This study uses sum frequency generation (SFG) vibrational spectroscopy and surface plasmon resonance (SPR) sensing to investigate the structure of sodium dodecyl sulfate (SDS) films formed on positively charged and hydrophilic surfaces. The SPR signals show a good surface coverage suggesting that full monolayer coverage is reached at 1 mM. SFG spectra of SDS adsorbed exhibits well resolved CH3 peaks and OH peaks. At both 0.2 mM and 1 mM SDS concentration the intensity of both the CH3 and OH peaks decreased close to background levels. We found that the loss of SFG signal at 0.2 mM occurs at this concentration independent of surface charge density. It is more likely that the loss of signal is related to structural inhomogeneity induced by a striped phase - stand-up phase transition. This is supported by a distinct change of the relative SFG phase between CH3/OH near 0.2 mM. The second intensity minimum might be related to charge compensation effects. We observed a substrate dependence for the high concentration transition. We also observed distinct SFG signal phase changes for water molecules associated with SDS layers at different SDS solution concentrations indicating that the orientation of bound water changed with SDS surface structure.

Co-overexpressing a plasma membrane and a vacuolar membrane sodium/proton antiporter significantly improves salt tolerance in transgenic Arabidopsis plants.

Science.gov (United States)

The Arabidopsis gene AtNHX1 encodes a vacuolar membrane bound sodium/proton (Sodium/Hydrogen) antiporter that transports sodium into the vacuole and exports hydrogen into the cytoplasm. The Arabidopsis gene SOS1 encodes a plasma membrane bound sodium/hydrogen antiporter that exports sodium to the ex...

Effect of sodium lauryl sulfate in dissolution media on dissolution of hard gelatin capsule shells.

Science.gov (United States)

Zhao, Fang; Malayev, Vyacheslav; Rao, Venkatramana; Hussain, Munir

2004-01-01

Sodium lauryl sulfate (SLS) is a commonly used surfactant in dissolution media for poorly water soluble drugs. However, it has occasionally been observed that SLS negatively impacts the dissolution of drug products formulated in gelatin capsules. This study investigated the effect of SLS on the dissolution of hard gelatin capsule shells. The USP paddle method was used with online UV monitoring at 214 nm (peptide bond). Empty size #0 capsule shells were held to the bottom of the dissolution vessel by magnetic three-prong sinkers. SLS significantly slowed down the dissolution of gelatin shells at pH < 5. Visually, the gelatin shells transformed into some less-soluble precipitate under these conditions. This precipitate was found to contain a higher sulfur content than the gelatin control sample by elemental analysis, indicating that SLS is part of the precipitate. Additionally, the slowdown of capsule shell dissolution was shown to be dependent on the SLS concentration and the ionic strength of the media. SLS interacts with gelatin to form a less-soluble precipitate at pH < 5. The use of SLS in dissolution media at acidic pH should be carefully evaluated for gelatin capsule products.

Long-term repetitive sodium lauryl sulfate-induced irritation of the skin: an in vivo study.

Science.gov (United States)

Branco, Nara; Lee, Ivy; Zhai, Hongbo; Maibach, Howard I

2005-11-01

Skin may adapt to topical irritants through accommodation. This study focuses on long-term exposure to irritants and attempts to demonstrate accommodation. Sodium lauryl sulfate (SLS) induced irritant contact dermatitis at 3 concentrations (0.025% to 0.075%). Distilled water, acetone and an empty chamber served as controls. Experimental compounds were applied to forearms of 7 healthy volunteers for 24 hr before replacing by a fresh chamber for 6 non-consecutive weeks over 103 days. Possible accommodation was quantified by visual scoring (erythema and dryness) and by bioengineering parameters: transepidermal water loss (TEWL), capacitance, chromametry and laser Doppler flowmetry (LDF). Significant erythema, dryness, elevated TEWL, skin colour reflectance and LDF values occurred during the exposure periods. Upon repeat exposure, an immediate and augmented response in erythema, TEWL, skin colour reflectance and LDF developed. However, irritant skin changes were not sustained. Irritation parameters return to baseline after cessation of exposure. There was no evidence of sustained irritation or accommodation after the last exposure. Study findings do not document sustained accommodation or adaptive hyposensitivity after long-term repetitive irritant exposure under these test conditions. Alternative models should be developed to prove or disprove the accommodation hypothesis.

Bicarbonate sulfate exchange in canalicular rat liver plasma membrane vesicles

International Nuclear Information System (INIS)

Meier, P.J.; Valantinas, J.; Hugentobler, G.; Rahm, I.

1987-01-01

The mechanism(s) and driving forces for biliary excretion of sulfate were investigated in canalicular rat liver plasma membrane vesicles (cLPM). Incubation of cLPM vesicles in the presence of an inside-to-outside (in, out) bicarbonate gradient but not pH or out-to-in sodium gradients, stimulated sulfate uptake 10-fold compared with the absence of bicarbonate and approximately 2-fold above sulfate equilibrium (overshoot). Initial rates of this bicarbonate gradient-driven [ 35 S]-sulfate uptake were saturable with increasing concentrations of sulfate and could be inhibited by probenecid, N-(4-azido-2-nitrophenyl)-2-aminoethylsulfonate, acetazolamide, furosemide, 4-acetamideo-4'-isothiocyanostilbene-2,2'-disulfonic acid, and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (IC 50 , ∼40 μM). Cisinhibition of initial bicarbonate gradient-stimulated sulfate uptake and transstimulation of sulfate uptake in the absence of bicarbonate were observed with sulfate, thiosulfate, and oxalate but not with chloride, nitrate, phosphate, acetate, lactate, glutamate, aspartate, cholate, taurocholate, dehydrocholate, taurodehydrocholate, and reduced or oxidized glutathione. These findings indicate the presence of a sulfate (oxalate)-bicarbonate anion exchange system in canalicular rat liver plasma membranes. These findings support the concept that bicarbonate-sensitive transport system might play an important role in bile acid-independent canalicular bile formation

Hydrogen detector

International Nuclear Information System (INIS)

Kumagaya, Hiromichi; Yoshida, Kazuo; Sanada, Kazuo; Chigira, Sadao.

1994-01-01

The present invention concerns a hydrogen detector for detecting water-sodium reaction. The hydrogen detector comprises a sensor portion having coiled optical fibers and detects hydrogen on the basis of the increase of light transmission loss upon hydrogen absorption. In the hydrogen detector, optical fibers are wound around and welded to the outer circumference of a quartz rod, as well as the thickness of the clad layer of the optical fiber is reduced by etching. With such procedures, size of the hydrogen detecting sensor portion can be decreased easily. Further, since it can be used at high temperature, diffusion rate is improved to shorten the detection time. (N.H.)

Hydrogen sulfide generation in shipboard oily-water waste. Part 3. Ship factors

Energy Technology Data Exchange (ETDEWEB)

Hodgeman, D.K.; Fletcher, L.E.; Upsher, F.J.

1995-04-01

The chemical and microbiological composition of bilge-water in ships of the Royal Australian Navy has been investigated in relation to the formation of hydrogen sulfide by sulfate-reducing bacteria. Sulfate-reducing bacteria were found in most ships in populations up to 800,000 per mL. Sulfate in the wastes is provided by sea-water. Sea-water constitutes up to 60% (median 20%) of the wastes analysed. Evidence for generation of hydrogen sulfide in the ships was found directly as sulfide or indirectly as depressed sulfate concentrations. The low levels of sulfide found in bilge-water from machinery spaces suggested the ventilation systems were effectively removing the gas from the working area. The effect of storage of the wastes under conditions which simulated the oily- water holding tanks of ships were also investigated. Some wastes were found to produce large quantities of hydrogen sulfide on storage. The wastes that failed to produce hydrogen sulfide were investigated to identify any specific nutritional deficiencies. Some organic substances present in bilge-water, such as lactate or biodegradable cleaning agents, and phosphate strongly influenced the generation of hydrogen sulfide in stored oily-water wastes.

Investigation into the role of sodium chloride deposited on oxide and metal substrates in the initiation of hot corrosion

Science.gov (United States)

Birks, N.

1983-01-01

Sodium chloride is deposited on the surface of alumina substrates and exposed to air containing 1% SO2 at temperatures between 500 C and 700 C. In all cases the sodium chloride was converted to sodium sulfate. The volatilization of sodium chloride from the original salt particles was responsible for the development of a uniform coating of sodium sulfate on the alumina substrate. At temperatures above 625 C, a liquid NaCl-Na2SO4 autectic was formed on the substrate. The mechanisms for these reactions are given. One of the main roles of NaCl in low temperature hot corrosion lies in enabling a corrosive liquid to form.

{tau} - hydrogen phosphate of zirconia in sodium salt form and some of its properties; {tau} - hidrogenofosfato de zirconio en forma sodica y algunas de sus propiedades

Energy Technology Data Exchange (ETDEWEB)

Fernandez V, S.M.; Ordonez R, E. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

2004-07-01

It is reported the obtaining and characterization in the sodium salt form of the {tau}-hydrogen phosphate of zirconium in sodium form, this compound it was synthesized, for a new technique developed in the laboratory of Dept. of Chemistry of the ININ. The characterization was carried out for XRD, IR, Sem and EDS the thermal gravimetric analysis is also reported. (Author)

Identification of impurities in sodium and its purification

International Nuclear Information System (INIS)

Subbotin, B.I.; Voltchkov, L.G.; Kozlov, F.A.; Zagorulko, Yu.I.; Kuznetsov, E.K.

1976-01-01

The paper presents some investigation results on sodium technology. In particular, a description is given of a calculation method for evaluation of sodium-cover gas-impurities equilibrium compositions as well as experimental results on development of methods for sodium sampling, equipment for non-metallic impurities (oxygen, hydrogen, carbon) constant control in sodium. The investigation results on sodium purification with cold traps are presented

Use of sodium dodecyl sulfate pretreatment and 2-stage curing for improved quality of salted duck eggs.

Science.gov (United States)

Lian, Zixuan; Qiao, Longshan; Zhu, Guanghong; Deng, Yun; Qian, Bingjun; Yue, Jin; Zhao, Yanyun

2014-03-01

The effects of use of sodium dodecyl sulfate (SDS) pretreatment and 2-stage curing on the microbial, physicochemical, and microstructural qualities of salted duck eggs were studied. After pretreatment in 0.5% (w/v) SDS solution at room conditions for 15 min, no discolorations were observed and no microorganisms were detected on the egg shells. In the 2-stage curing process, 25% (w/v) and 30% (w/v) saline solutions were evaluated in the 1st step (Stage I, approximately 18 d), whereas 4% (w/v) saline solution was applied in the 2nd step (Stage II, approximately 15 d). Along with increased curing time, water content decreased and NaCl content increased in the egg yolks from approximately 0.40% to 0.86%, whereas the water content of egg albumen remained at approximately 85% during the 2-stage curing. More importantly, the NaCl content of albumen maintained at approximately 4.0% at Stage II curing. Yolk index as a sign of maturity for salted duck eggs reached 1 at the end of Stage I (18 d) and retained the same value during Stage II curing regardless of the NaCl concentration in the Stage I saline solution. Oil exudation in egg yolks increased as the time of curing increased. As seen from scanning electron microscopy, oil was released from yolk granules. This study indicated that SDS pretreatment is effective to reduce microbial load on the shells of fresh duck eggs and the 2-stage curing can improve physicochemical qualities of the salted duck eggs and shortened curing time to about 7 to 17 d as compared to the traditional 1-step curing method. Spoiled saline solution and uneven distribution of salt are the 2 major problems in producing salted duck eggs. Sodium dodecyl sulfate (SDS) pretreatment and 2-stage curing process have shown effective to solve these problems, respectively. The SDS pretreatment was able to remove microorganisms and soil from the surface of fresh egg shells, thus preventing the spoilage of the saline solution. The 2-stage curing process

Electrochemical hydrogen Storage Systems

International Nuclear Information System (INIS)

Macdonald, Digby

2010-01-01

As the global need for energy increases, scientists and engineers have found a possible solution by using hydrogen to power our world. Although hydrogen can be combusted as a fuel, it is considered an energy carrier for use in fuel cells wherein it is consumed (oxidized) without the production of greenhouse gases and produces electrical energy with high efficiency. Chemical storage of hydrogen involves release of hydrogen in a controlled manner from materials in which the hydrogen is covalently bound. Sodium borohydride and aminoborane are two materials given consideration as chemical hydrogen storage materials by the US Department of Energy. A very significant barrier to adoption of these materials as hydrogen carriers is their regeneration from 'spent fuel,' i.e., the material remaining after discharge of hydrogen. The U.S. Department of Energy (DOE) formed a Center of Excellence for Chemical Hydrogen Storage, and this work stems from that project. The DOE has identified boron hydrides as being the main compounds of interest as hydrogen storage materials. The various boron hydrides are then oxidized to release their hydrogen, thereby forming a 'spent fuel' in the form of a lower boron hydride or even a boron oxide. The ultimate goal of this project is to take the oxidized boron hydrides as the spent fuel and hydrogenate them back to their original form so they can be used again as a fuel. Thus this research is essentially a boron hydride recycling project. In this report, research directed at regeneration of sodium borohydride and aminoborane is described. For sodium borohydride, electrochemical reduction of boric acid and sodium metaborate (representing spent fuel) in alkaline, aqueous solution has been investigated. Similarly to literature reports (primarily patents), a variety of cathode materials were tried in these experiments. Additionally, approaches directed at overcoming electrostatic repulsion of borate anion from the cathode, not described in the

Electrochemical hydrogen Storage Systems

Energy Technology Data Exchange (ETDEWEB)

Dr. Digby Macdonald

2010-08-09

As the global need for energy increases, scientists and engineers have found a possible solution by using hydrogen to power our world. Although hydrogen can be combusted as a fuel, it is considered an energy carrier for use in fuel cells wherein it is consumed (oxidized) without the production of greenhouse gases and produces electrical energy with high efficiency. Chemical storage of hydrogen involves release of hydrogen in a controlled manner from materials in which the hydrogen is covalently bound. Sodium borohydride and aminoborane are two materials given consideration as chemical hydrogen storage materials by the US Department of Energy. A very significant barrier to adoption of these materials as hydrogen carriers is their regeneration from 'spent fuel,' i.e., the material remaining after discharge of hydrogen. The U.S. Department of Energy (DOE) formed a Center of Excellence for Chemical Hydrogen Storage, and this work stems from that project. The DOE has identified boron hydrides as being the main compounds of interest as hydrogen storage materials. The various boron hydrides are then oxidized to release their hydrogen, thereby forming a 'spent fuel' in the form of a lower boron hydride or even a boron oxide. The ultimate goal of this project is to take the oxidized boron hydrides as the spent fuel and hydrogenate them back to their original form so they can be used again as a fuel. Thus this research is essentially a boron hydride recycling project. In this report, research directed at regeneration of sodium borohydride and aminoborane is described. For sodium borohydride, electrochemical reduction of boric acid and sodium metaborate (representing spent fuel) in alkaline, aqueous solution has been investigated. Similarly to literature reports (primarily patents), a variety of cathode materials were tried in these experiments. Additionally, approaches directed at overcoming electrostatic repulsion of borate anion from the cathode, not

Ecotoxicological assessment of the pharmaceutical fluoxetine hydrochloride and the surfactant dodecyl sodium sulfate after their submission to ionizing radiation treatment

International Nuclear Information System (INIS)

Santos, Dymes Rafael Alves dos

2011-01-01

The use of pharmaceuticals and personal care products and the consequent and continuous input of this substances in the environment generates an increasing need to investigate the presence, behavior and the effects on aquatic biota, as well as new ways to treat effluents containing such substances. Fluoxetine hydrochloride is an active ingredient used in the treatment of depressive disorders and anxiety. As the surfactant sodium dodecyl sulfate is present in many cleaning and personal care products. The present study aimed on assessing the acute toxicity of fluoxetine hydrochloride, sodium dodecyl sulfate and the mixture of both to the aquatic organisms Hyalella azteca, Daphnia similis and Vibrio ficheri. Reducing the toxicity of fluoxetine and the mixture after treatment with ionizing radiation from industrial electron beam accelerator has also been the focus of this study. For Daphnia similis the average values of CE50-4 8h found for the non-irradiated drug, surfactant and mixture were 14.4 %, 9.62 % and 13.8 %, respectively. After irradiation of the substances, the dose 5 kGy proved itself to be the most effective dose for the treatment of the drug and the mixture as it was obtained the mean values for CE50 48h 84.60 % and > 90 %, respectively. For Hyalella azteca the acute toxicity tests were performed for water column with duration of 96 hours, the mean values for CE50 96h found for the drug, the surfactant and the mixture non-irradiated were 5.63 %, 19.29 %, 6.27 %, respectively. For the drug fluoxetine and the mixture irradiated with 5 kGy, it was obtained 69.57 % and 77.7 %, respectively. For Vibrio ficheri the acute toxicity tests for the untreated drug and the drug irradiated with 5 kGy it was obtained CE50 15min of 6.9 % and 32.88 % respectively. These results presented a reduction of the acute toxicity of the test-substances after irradiation. (author)

Transcatheter Foam Sclerotherapy of Symptomatic Female Varicocele with Sodium-Tetradecyl-Sulfate Foam

International Nuclear Information System (INIS)

Gandini, Roberto; Chiocchi, Marcello; Konda, Daniel; Pampana, Enrico; Fabiano, Sebastiano; Simonetti, Giovanni

2008-01-01

To evaluate the efficacy of transcatheter foam sclerotherapy (TCFS) in pelvic varicocele using sodium-tetradecyl-sulfate foam (STSF), we conducted a retrospective study in 38 patients (mean age, 36.9 years; range, 22-44 years) with pelvic congestion syndrome (PCS) treated between January 2000 and June 2005 by TCFS. Pelvic pain was associated with dyspareunia in 23 (60.5%) patients, urinary urgency in 9 (23.7%) patients, and worsening of pain during menstruation and at the end of a day of work in 7 (18.4%) and 38 (100%) patients, respectively. Diagnosis was made by pelvic and transvaginal color Doppler ultrasound examination, demonstrating ovarian or pelvic varices with a diameter >5 mm presenting venous reflux. TCFS was performed in all patients, using 3% STSF. Follow-up was performed by physical examination, pelvic and transvaginal Doppler ultrasound examination and by a questionnaire-based assessment of pain at 1, 3, 6, and 12 months after the procedure. Technical success was achieved in all patients (100%). In three patients a pelvic colic-like pain occurred immediately after sclerotic agent injection, disappearing spontaneously after a few minutes. No recurrent varicoceles were observed during a 12-month follow-up. A statistically significant improvement in each category of specific symptoms was observed at 1, 3, 6, and 12 months after the procedure. We conclude that TCFS of female varicocele using a 3% STSF is safe and effective for the treatment of PCS. It is associated with a significant reduction of symptoms and can be regarded as a valid alternative to other endovascular and surgical techniques.

Comparison of adsorption equilibrium models and error functions for the study of sulfate removal by calcium hydroxyapatite microfibrillated cellulose composite.

Science.gov (United States)

Hokkanen, Sanna; Bhatnagar, Amit; Koistinen, Ari; Kangas, Teija; Lassi, Ulla; Sillanpää, Mika

2018-04-01

In the present study, the adsorption of sulfates of sodium sulfate (Na 2 SO 4 ) and sodium lauryl sulfate (SLS) by calcium hydroxyapatite-modified microfibrillated cellulose was studied in the aqueous solution. The adsorbent was characterized using elemental analysis, Fourier transform infrared, scanning electron microscope and elemental analysis in order to gain the information on its structure and physico-chemical properties. The adsorption studies were conducted in batch mode. The effects of solution pH, contact time, the initial concentration of sulfate and the effect of competing anions were studied on the performance of synthesized adsorbent for sulfate removal. Adsorption kinetics indicated very fast adsorption rate for sulfate of both sources (Na 2 SO 4 and SLS) and the adsorption process was well described by the pseudo-second-order kinetic model. Experimental maximum adsorption capacities were found to be 34.53 mg g -1 for sulfates of SLS and 7.35 mg g -1 for sulfates of Na 2 SO 4. The equilibrium data were described by the Langmuir, Sips, Freundlich, Toth and Redlich-Peterson isotherm models using five different error functions.

Sulfate reduction with methanol by a thermophilic consortium obtained from a methanogenic reactor

Energy Technology Data Exchange (ETDEWEB)

Davidova, I.A. [Wageningen Agricultural Univ. (Netherlands). Dept. of Microbiology; Stams, A.J.M. [Wageningen Agricultural Univ. (Netherlands). Dept. of Microbiology

1996-12-31

An enrichment culture obtained from anaerobic granular sludge of a bench-scale anarobic reactor degraded methanol at 65 C via sulfate reduction and acetogenesis. Sulfate reduction was the dominant process (S{sup 2-}/acetate=2.5). No methane formation was observed. Approximately 30% of the methanol was converted by acetogenic bacteria to acetate, while the remainder was degraded by these bacteria to H{sub 2} and CO{sub 2} in syntrophy with hydrogen-consuming sulfate-reducing bacteria. Pure cultures of sulfate-reducing and acetogenic bacteria were isolated and characterized. (orig.)

Foam capacity and stability of Sodium Dodecyl Sulfate (SDS) on the presence of contaminant coffee and Cd ions in solution

Science.gov (United States)

Haryanto, B.; Chang, C. H.; Kuo, A. T.; Siswarni, M. Z.; Sinaga, T. M. A.

2018-02-01

In this study, the effect of the coffee colloidal particle and Cd ion contaminant on the foam capacity and stability of sodium dodecyl sulfate (SDS) solution was investigated. The foam was generated by using a foam generator. The foam capacity of SDS was first evaluated at different concentrations. After the foam capacity reaching a constant value, the foam stability was then measured by flowing to a column. The results showed that the presence the coffee colloidal particles or Cd ions in the solution would decrease the foam capacity and stability of SDS. In addition, the decreased foam capacity and stability was more pronounced in the presence of coffee colloidal particles than Cd ions. The colloidal particles may have stronger interaction with SDS and thus reduce the formation of the foam.

Effective oxidation of benzylic and alkane C-H bonds catalyzed by sodium o-iodobenzenesulfonate with Oxone as a terminal oxidant under phase-transfer conditions.

Science.gov (United States)

Cui, Li-Qian; Liu, Kai; Zhang, Chi

2011-04-07

Catalytic oxidation of benzylic C-H bonds could be efficiently realized using IBS as a catalyst which was generated in situ from the oxidation of sodium 2-iodobenzenesulfonate (1b) by Oxone in the presence of a phase-transfer catalyst, tetra-n-butylammonium hydrogen sulfate, in anhydrous acetonitrile at 60 °C. Various alkylbenzenes, including toluenes and ethylbenzenes, several oxygen-containing functionalities substituted alkylbenzenes, and a cyclic benzyl ether could be efficiently oxidized. And, the same reagent system of cat. 1b/Oxone/cat. n-Bu(4)NHSO(4) could be applied to the effective oxidation of alkanes as well.

Palladium coated fibre Bragg grating based hydrogen sensor

International Nuclear Information System (INIS)

Kasinathan, M.; Sosamma, S.; Kishore, S.; Elumalai, V.; Krishnan, R.; Babu Rao, C.; Dash, Sitaram; Murali, N.; Jayakumar, T.

2011-01-01

Detection of steam generator leaks in fast nuclear reactors is carried out by monitoring hydrogen in argon cover-gas. Hydrogen released during sodium cleaning of fast reactor components is required to be monitored. Hydrogen sensors with good sensitivity, stability and response time are required for all the above applications. We report a new type of hydrogen sensor with a Fibre Bragg Grating (FBG) coated with palladium thin film which is used to detect the leak of hydrogen gas in the Steam Generator (SG) module of the Fast Breeder Reactor (FBR). If water leaks into sodium, it results in sodium-water reaction. In this reaction hydrogen and sodium hydroxide are formed. Due to the explosive risk of hydrogen system, hydrogen sensors are of great interest in this case. It is known that hydrogen forms an explosive mixture with air once its concentration exceeds beyond the explosion limit of four percent. The advantages of FBG based hydrogen sensor over the other hydrogen sensors are its inherent property of safety from sparking, immunity to ambient electromagnetic interference. The sensing mechanism in this device is based on mechanical strain that is induced in the palladium coating when it absorbs hydrogen. This process physically stretches the grating and causes the grating period and grating's refractive index, to change. The Bragg wavelength shift is directly proportional to the strain induced and can be directly related to the percentage of hydrogen exposure. The online monitoring of palladium thin film coating on FBG is carried out and recorded the wavelength change and strain induced on the FBG. A hydrogen sensor set up have been fabricated which consists of SS vessel of capacity 10 litres, provided with pressure gauge, Argon filling line with a valve, Hydrogen injection line with flange, a vent line with valve and Hydrogen sensor fixing point. The Palladium coated FBG based Hydrogen sensor is tested in this experimental facility in the exposure of hydrogen in

Study on the utilization of a sodium-sulfuric acid solution for the uranium minerals' leaching

International Nuclear Information System (INIS)

Echenique, Patricia; Fruchtenicht, Fernando; Gil, Daniel; Vigo, Daniel; Bouza, Angel; Vert, Gabriela; Becquart, Elena

1988-01-01

Argentine uranium minerals have been leached at bench scale with a different agent trying to reduce sulfuric acid consumption. The leaching agent was a sodium sulfate-sulfuric acid solution and the ore was from Sierra Pintada (San Rafael - Mendoza). The work was performed in stirred vessel at atmospheric pressure. The influence of different variables, pH, temperature, oxidant agent, sodium sulfate concentration and time, in the sulfuric acid consumption and the uranium yield was studied. (Author) [es

Reduction and precipitation of neptunium(V) by sulfate-reducing bacteria

International Nuclear Information System (INIS)

Banaszak, J. E.; Rittmann, B. E.; Reed, D. T.

1999-01-01

Migration of neptunium, as NpO 2 + , has been identified as a potentially important pathway for actinide release at nuclear waste repositories and existing sites of subsurface contamination. Reduction of Np(V) to Np(IV) will likely reduce its volubility, resulting in lowered subsurface migration. The ability of sulfate-reducing bacteria (SRB) to utilize Np(V) as an electron acceptor was investigated, because these bacteria are active in many anaerobic aquifers and are known to facilitate the reduction of metals and radionuclides. Pure and mixed cultures of SRB were able to precipitate neptunium during utilization of pyruvate, lactate, and hydrogen as electron donors in the presence and absence of sulfate. The neptunium in the precipitate was identified as Np(IV) using X-ray absorption near edge spectroscopy (XANES) analysis. In mixed-culture studies, the addition of hydrogen to consortia grown by pyruvate fermentation stimulated neptunium reduction and precipitation. Experiments with pure cultures of Desulfovibrio vulgaris, growing by lactate fermentation in the absence of sulfate or by sulfate reduction, confirm that the organism is active in neptunium reduction and precipitation. Based on our results, the activity of SRB in the subsurface may have a significant, and potentially beneficial, impact on actinide mobility by reducing neptunium volubility

Experimental study of hydrogen formation and recombination under postulated LMFBR accident conditions

International Nuclear Information System (INIS)

Wierman, R.W.; Hilliard, R.K.

1976-01-01

The report describes an experimental study of hydrogen jets burning in air, hydrogen formation by sodium in humid air atmospheres, and the effects of nitrogen, water vapor sodium vapor/aerosol, jet velocity, and jet temperature on ignition of hydrogen jets. The results show that hydrogen jets above 1450 0 F (788 0 C) issuing into an air atmosphere need no ignition source for ignition, a hydrogen jet temperature higher than 500 0 F (260 0 C) and containing more than six grams of sodium per cubic meter of jet gas will auto-ignite in an air atmosphere, the burning efficiency of a hydrogen jet decreases rapidly to zero when the oxygen concentration outside the flame region approaches 10 percent, and hydrogen does not form from a sodium-nitrogen jet issuing into a humid air atmosphere until the ratio O 2 /(H 2 O + O 2 ) is less than 0.5

An electrochemical sensor for sodium dodecyl sulfate detection based on anion exchange using eosin Y/polyethyleneimine modified electrode.

Science.gov (United States)

Hao, Xia; Lei, Jing Lei; Li, Nian Bing; Luo, Hong Qun

2014-12-10

A simple and effective method for the detection of electrochemically inactive sodium dodecyl sulfate (SDS) has been designed, based on different binding affinity of polyethyleneimine (PEI) toward electrochemically active eosin Y and electrochemically inactive SDS. The stronger binding affinity of the PEI toward SDS than eosin Y results in the decrease of the redox peak current of surface confined eosin Y and provides a quantitative readout for the SDS. The difference in value of the cathodic peak current showed a linear relationship with SDS concentration in a concentration range from 1 to 40 μg mL(-1), and a detection limit of 0.9 μg mL(-1) for SDS was obtained. Furthermore, the method has been successfully applied to the detection of SDS in real samples. The developed approach provided a simple and reliable detection for SDS and might have potential applications in electrochemical methods for inactive molecules. Copyright © 2014 Elsevier B.V. All rights reserved.

Bovine milk-derived α-lactalbumin inhibits colon inflammation and carcinogenesis in azoxymethane and dextran sodium sulfate-treated mice.

Science.gov (United States)

Yamaguchi, Makoto; Takai, Shoko; Hosono, Akira; Seki, Taiichiro

2014-01-01

Cyclooxygenase-2 is expressed early in colon carcinogenesis and plays crucial role in the progress of the disease. Recently, we found that α-lactalbumin had anti-inflammatory activity by inhibiting cyclooxygenase-2. In experiment 1, we investigated the effects of α-lactalbumin on the colon carcinogenesis initiated with azoxymethane (AOM) followed by promotion with dextran sodium sulfate (DSS) in mice. Dietary treatment with α-lactalbumin decreased fecal occult blood score at 3 days after DSS intake. α-Lactalbumin also decreased the colon tumor at week 9. In experiment 2, AOM-treated mice were sacrificed at 7 days after DSS intake. The plasma and colon prostaglandin E2 (PGE2) levels in AOM/DSS-treated mice were higher than those in the DSS-treated mice without initiation by AOM. α-Lactalbumin decreased PGE2 in both plasma and colon. These results suggest that α-lactalbumin effectively inhibited colon carcinogenesis, and the inhibition may be due to the decreased PGE2 by inhibiting cyclooxygenase-2 at cancer promotion stages.

Effect of processed Scutellaria baicalensis on dextran sulfate sodium-induced colitis in mice.

Science.gov (United States)

Choi, Yeon-A; Kang, Ok-Hwa; Park, Hye-Jung; Tae, Jin; Kim, Dae-Ki; Kang, Chon Sik; Choi, Suck-Chei; Yun, Ki-Jung; Choi, Suck-Jun; Nah, Yong-Ho; Kim, Young-Ho; Bae, Ki-Hwan; Lee, Young-Mi

2005-10-01

Scutellaria baicalensis Georgi (Labiatae) has been used in the treatment of inflammatory diseases. Drug processing (Poje) is the process of treating crude drugs by several methods before use. The aim of this study was to determine the effect of processed Scutellaria baicalensis on experimental ulcerative colitis induced by dextran sulfate sodium (DSS). The types of processed Scutellaria baicalensis used in this study were parched Scutellaria baicalensis (PS) and rice wine-baked Scutellaria baicalensis (RWBS). Experimental colitis was induced in mice using a daily treatment of 5% DSS in the drinking water for 7 days. The water extracts of processed Scutellaria baicalensis (1 g/kg) were administered orally once a day for 7 days. The mice were divided in four groups: i) water plus DSS group, ii) crude Scutellaria baicalensis (CS) plus DSS group, iii) PS plus DSS group, and iv) RWBS plus DSS group. RWBS ameliorated all of the inflammatory symptoms, such as body weight loss, rectal bleeding and histological damage, compared to CS. Furthermore, RWBS significantly reduced the mucosal myeloperoxidase activity, and TNF-alpha (tumor necrosis factor-alpha), COX-2 (cyclooxygenase-2), NF-kappaB (nuclear factor-kappa B) and chymase expression more than CS. But these effects were not shown in the PS plus DSS group. Efficacy of Scutellaria baicalensis was increased after rice wine baking, but not after parching. The findings in this study suggest that RWBS may be a useful therapeutic agent for ulcerative colitis.

The Dynamics of Interleukin-10-Afforded Protection during Dextran Sulfate Sodium-Induced Colitis

Science.gov (United States)

Cardoso, Ana; Gil Castro, Antonio; Martins, Ana Catarina; Carriche, Guilhermina M.; Murigneux, Valentine; Castro, Isabel; Cumano, Ana; Vieira, Paulo; Saraiva, Margarida

2018-01-01

Inflammatory bowel disease encompasses a group of chronic-inflammatory conditions of the colon and small intestine. These conditions are characterized by exacerbated inflammation of the organ that greatly affects the quality of life of patients. Molecular mechanisms counteracting this hyperinflammatory status of the gut offer strategies for therapeutic intervention. Among these regulatory molecules is the anti-inflammatory cytokine interleukin (IL)-10, as shown in mice and humans. Indeed, IL-10 signaling, particularly in macrophages, is essential for intestinal homeostasis. We sought to investigate the temporal profile of IL-10-mediated protection during chemical colitis and which were the underlying mechanisms. Using a novel mouse model of inducible IL-10 overexpression (pMT-10), described here, we show that mice preconditioned with IL-10 for 8 days before dextran sulfate sodium (DSS) administration developed a milder colitic phenotype. In IL-10-induced colitic mice, Ly6C cells isolated from the lamina propria showed a decreased inflammatory profile. Because our mouse model leads to transcription of the IL-10 transgene in the bone marrow and elevated seric IL-10 concentration, we investigated whether IL-10 could imprint immune cells in a long-lasting way, thus conferring sustained protection to colitis. We show that this was not the case, as IL-10-afforded protection was only observed if IL-10 induction immediately preceded DSS-mediated colitis. Thus, despite the protection afforded by IL-10 in colitis, novel strategies are required, specifically to achieve long-lasting protection. PMID:29545807

An Eco-Friendly Improved Protocol for the Synthesis of Bis(3-indolyl)methanes Using Poly(4-vinylpyridinium)hydrogen Sulfate as Efficient, Heterogeneous, and Recyclable Solid Acid Catalyst

Science.gov (United States)

Banothu, Janardhan; Gali, Rajitha; Velpula, Ravibabu; Bavantula, Rajitha; Crooks, Peter A.

2013-01-01

Highly efficient and eco-friendly protocol for the synthesis of bis(3-indolyl)methanes by the electrophilic substitution reaction of indole with aldehydes catalyzed by poly(4-vinylpyridinium)hydrogen sulfate was described. Excellent yields, shorter reaction times, simple work-up procedure, avoiding hazardous organic solvents, and reusability of the catalyst are the most obvious advantages of this method. PMID:24052864

A bio-inspired molecular water oxidation catalyst for renewable hydrogen generation: an examination of salt effects

Science.gov (United States)

Brimblecombe, Robin; Rotstein, Miriam; Koo, Annette; Dismukes, G. Charles; Swiegers, Gerhard F.; Spiccia, Leone

2009-08-01

Most transport fuels are derived from fossil fuels, generate greenhouse gases, and consume significant amounts of water in the extraction, purification, and/or burning processes. The generation of hydrogen using solar energy to split water, ideally from abundant water sources such as sea water or other non-potable sources, could potentially provide an unlimited, clean fuel for the future. Solar, electrochemical water splitting typically combines a photoanode at which water oxidation occurs, with a cathode for proton reduction to hydrogen. In recent work, we have found that a bioinspired tetra-manganese cluster catalyzes water oxidation at relatively low overpotentials (0.38 V) when doped into a Nafion proton conduction membrane deposited on a suitable electrode surface, and illuminated with visible light. We report here that this assembly is active in aqueous and organic electrolyte solutions containing a range of different salts in varying concentrations. Similar photocurrents were obtained using electrolytes containing 0.0 - 0.5 M sodium sulfate, sodium perchlorate or sodium chloride. A slight decline in photocurrent was observed for sodium perchlorate but only at and above 5.0 M concentration. In acetonitrile and acetone solutions containing 10% water, increasing the electrolyte concentration was found to result in leaching of the catalytic species from the membrane and a decrease in photocurrent. Leaching was not observed when the system was tested in an ionic liquid containing water, however, a lower photocurrent was generated than observed in aqueous electrolyte. We conclude that immersion of the membrane in an aqueous solution containing an electrolyte concentration of 0.05 - 0.5M represent good conditions for operation for the cubium/Nafion catalytic system.

Conformational studies of human [15-2-aminohexanoic acid]little gastrin in sodium dodecyl sulfate micelles by 1H NMR

International Nuclear Information System (INIS)

Mammi, S.; Peggion, E.

1990-01-01

Human little gastrin is a 17 amino acid peptide that adopts a random conformation in water and an ordered structure in sodium dodecyl sulfate (SDS) micelles as well as in trifluoroethanol (TFE). The circular dichroism spectra in these two media have the same shape, indicative of a similar preferred conformation. The authors describe here the assignment of the proton NMR resonances and the conformational analysis of [Ahx 15 ] little gastrin in SDS micelles. Two-dimensional correlation techniques form the basis for the assignment. The conformational analysis utilizes NOE's, NH to C α H coupling constants, and the temperature coefficients of the amide chemical shifts. The NMR data indicate a helical structure in the N-terminal portion of the peptide. These results are compared with the conformation that the authors recently proposed for a minigastrin analogue (fragment 5-17 of [Ahx 15 ] little gastrin) in TFE

Presence of hydrogen peroxide, a source of hydroxyl radicals, in acid electrolyzed water.

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Takayuki Mokudai

Full Text Available BACKGROUND: Acid electrolyzed water (AEW, which is produced through the electrolysis of dilute sodium chloride (NaCl or potassium chloride solution, is used as a disinfectant in various fields because of its potent antimicrobial activity. The hydroxyl radical, an oxygen radical species, is often suggested as a putative active ingredient for AEW antimicrobial activity. METHODOLOGY/PRINCIPAL FINDINGS: The aim of the present study is to detect hydroxyl radicals in AEW. The hydroxyl radicals in AEW prepared under different conditions were determined using an electron spin resonance (ESR technique. A signal from 5,5-dimethyl-1-pyrroline N-oxide (DMPO-OH, an adduct of DMPO and the hydroxyl radical, was detected in AEW prepared by double or triple electrolyses of 1% NaCl but not of 0.1% NaCl solution. Then the presence of hydrogen peroxide as a proposed source of hydroxyl radicals was examined using a combination of ESR and a Fenton reaction. The DMPO-OH signal was clearly detected, even in AEW prepared by single electrolysis of 0.1% NaCl solution, when ferrous sulfate was added to induce a Fenton reaction, indicating the presence of hydrogen peroxide in the AEW. Since sodium formate, a hydroxyl radical scavenger, did not affect the bactericidal activity of AEW, it is concluded that the radical is unlikely to contribute to the antimicrobial activity of AEW, although a small amount of the radical is produced from hydrogen peroxide. Dimethyl sulfoxide, the other hydroxyl radical scavenger used in the present study, canceled the bactericidal activity of AEW, accompanied by complete depletion of free available chlorine, suggesting that hypochlorous acid is probably a major contributor to the antimicrobial activity. CONCLUSIONS: It is strongly suggested that although hydrogen peroxide is present in AEW as a source of hydroxyl radicals, the antimicrobial activity of AEW does not depend on these radicals.

pH-dependent differential interacting mechanisms of sodium dodecyl sulfate with bovine serum fetuin: a biophysical insight.

Science.gov (United States)

Zaidi, Nida; Nusrat, Saima; Zaidi, Fatima Kamal; Khan, Rizwan H

2014-11-20

Sodium dodecyl sulfate (SDS)-glycoprotein interaction serves as a model for a biological membrane. To get mechanistic insight into the interaction of SDS and glycoprotein, the effect of SDS on bovine serum fetuin (BSF) was studied in subcritical micellar concentrations at pH 7.4 and pH 2 using multiple approaches. SDS interacts electrostatically with BSF through its negatively charged head groups at pH 2 and hydrophobically via its alkyl chains at pH 7.4 up to a 1:20 molar ratio of BSF to SDS. However, at higher concentrations of SDS, BSF undergoes amyloid fibril formation at pH 2, as confirmed by enhanced ThT fluorescence, β-sheet formation, and TEM microscopy, whereas BSF undergoes induction of an α-helical structure in the presence of higher SDS concentration at pH 7.4. The increase in α-helical content with increasing SDS concentrations constrains the environment around tryptophan. As a consequence, the interconversion of tryptophan conformers decreases, resulting in a decrement of the fluorescence lifetime for BSF in the presence of SDS at pH 7.4.

Effect of sodium lauryl sulfate on recurrent aphthous stomatitis: a randomized controlled clinical trial.

Science.gov (United States)

Shim, Y J; Choi, J-H; Ahn, H-J; Kwon, J-S

2012-10-01

To compare the effects of sodium lauryl sulfate (SLS)-free and SLS-containing dentifrice in patient with recurrent aphthous stomatitis (RAS). The design of this study was a double-blind crossover trial. The 90 subjects were divided into three groups: group I used SLS-free (a commercially available SLS-free dentifrice) and SLS-A (SLS-free + 1.5% SLS), group II used SLS-A and SLS-B (a commercially available 1.5% SLS-containing dentifrice), and group III used SLS-free and SLS-B. The subjects used one of the two assigned dentifrices for 8 weeks and then the other for the following 8 weeks. The order of the dentifrices used was selected at random, and there was a 2-week washout period between the two phases. The clinical parameters (number of ulcers, number of episodes, duration of ulcers, mean pain score) were compared between the two phases for each group. The number of ulcers and episodes did not differ significantly between SLS-A, SLS-B, and SLS-free. Only duration of ulcers and mean pain score was significantly decreased during the period using SLS-free. Although SLS-free did not reduce the number of ulcers and episodes, it affected the ulcer-healing process and reduces pain in daily lives in patients with RAS. © 2012 John Wiley & Sons A/S.

Prophylactic role of curcumin in dextran sulfate sodium (DSS)-induced ulcerative colitis murine model.

Science.gov (United States)

Arafa, Hossam M M; Hemeida, Ramadan A; El-Bahrawy, Ali I M; Hamada, Farid M A

2009-06-01

We have addressed in this study the possible protective role of the main principle of turmeric pigment; curcumin on a murine model of ulcerative colitis (UC). Colitis was induced by administration of dextran sulfate sodium (DSS) (3% W/V) in drinking water to male Swiss albino rats for 5 consecutive days. DSS challenge induced UC model that was well characterized morphologically and biochemically. DSS produced shrinkage of colon length and increased the relative colon weight/length ratio accompanied by mucosal edema and bloody stool. Histologically, DSS produced submucosal erosions, ulceration, inflammatory cell infiltration and crypt abscess as well as epithelioglandular hyperplasia. The model was confirmed biochemically, and the test battery entailed elevated serum tumor necrosis factor (TNF-alpha) and colonic activity of myleoperoxidase (MPO). Colonic glutathione-S-transferase (GST) activity and its substrate concentration; GSH, were notably reduced, while lipid peroxidation, expressed as malondialdehyde (MDA) level, and total nitric oxide (NO) were significantly increased. Prior administration of curcumin (100mg/kg, IP) for 7 consecutive days ahead of DSS challenge mitigated the injurious effects of DSS and ameliorated all the altered biochemical parameters. These results suggest that curcumin could possibly have a protective role in ulcerative colitis probably via regulation of oxidant/anti-oxidant balance and modulation of the release of some inflammatory endocoids, namely TNF-alpha and NO.

Study of adjuvant effect of model surfactants from the groups of alkyl sulfates, alkylbenzene sulfonates, alcohol ethoxylates and soaps

DEFF Research Database (Denmark)

Clausen, S K; Sobhani, S; Poulsen, O M

2000-01-01

The sodium salts of representatives of anionic surfactants, dodecylbenzene sulfonate (SDBS), dodecyl sulfate (SDS) and coconut oil fatty acids, and a nonionic surfactant, dodecyl alcohol ethoxylate, were studied for adjuvant effect on the production of specific IgE antibodies in mice. The surfact......The sodium salts of representatives of anionic surfactants, dodecylbenzene sulfonate (SDBS), dodecyl sulfate (SDS) and coconut oil fatty acids, and a nonionic surfactant, dodecyl alcohol ethoxylate, were studied for adjuvant effect on the production of specific IgE antibodies in mice...

A novel sodium iodide and ammonium molybdate co-catalytic system for the efficient synthesis of 2-benzimidazoles using hydrogen peroxide under ultrasound irradiation.

Science.gov (United States)

Bai, Guo-Yi; Lan, Xing-Wang; Chen, Guo-Feng; Liu, Xiao-Fang; Li, Tian-Yu; Shi, Ling-Juan

2014-03-01

The reaction of aldehydes and o-phenylenediamine for the preparation of 2-benzimidazoles has been studied using hydrogen peroxide as an oxidant under ultrasound irradiation at room temperature in this paper. The combination of substoichiometric sodium iodide and ammonium molybdate as co-catalysts, together with using small amounts of hydrogen peroxide, makes this transformation very efficient and attractive under ultrasound. Thus, a mild, green and efficient method is established to carry out this reaction in high yield. Copyright © 2013 Elsevier B.V. All rights reserved.

Strawberry Phytochemicals Inhibit Azoxymethane/Dextran Sodium Sulfate-Induced Colorectal Carcinogenesis in Crj: CD-1 Mice

Directory of Open Access Journals (Sweden)

Ni Shi

2015-03-01

Full Text Available Human and experimental colon carcinogenesis are enhanced by a pro-inflammatory microenvironment. Pharmacologically driven chemopreventive agents and dietary variables are hypothesized to have future roles in the prevention of colon cancer by targeting these processes. The current study was designed to determine the ability of dietary lyophilized strawberries to inhibit inflammation-promoted colon carcinogenesis in a preclinical animal model. Mice were given a single i.p. injection of azoxymethane (10 mg kg−1 body weight. One week after injection, mice were administered 2% (w/v dextran sodium sulfate in drinking water for seven days and then an experimental diet containing chemically characterized lyophilized strawberries for the duration of the bioassay. Mice fed control diet, or experimental diet containing 2.5%, 5.0% or 10.0% strawberries displayed tumor incidence of 100%, 64%, 75% and 44%, respectively (p < 0.05. The mechanistic studies demonstrate that strawberries reduced expression of proinflammatory mediators, suppressed nitrosative stress and decreased phosphorylation of phosphatidylinositol 3-kinase, Akt, extracellular signal-regulated kinase and nuclear factor kappa B. In conclusion, strawberries target proinflammatory mediators and oncogenic signaling for the preventive efficacies against colon carcinogenesis in mice. This works supports future development of fully characterized and precisely controlled functional foods for testing in human clinical trials for this disease.

The Influence of Ghrelin on the Development of Dextran Sodium Sulfate-Induced Colitis in Rats

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Aleksandra Matuszyk

2015-01-01

Full Text Available Ghrelin has protective and therapeutic effects in the gut. The aim of present studies was to investigate the effect of treatment with ghrelin on the development of colitis evoked by dextran sodium sulfate (DSS. Methods. Studies have been performed on rats. Colitis was induced by adding 5% DSS to the drinking water for 5 days. During this period animals were treated intraperitoneally twice a day with saline or ghrelin given at the dose of 8 nmol/kg/dose. On the sixth day, animals were anesthetized and the severity of colitis was assessed. Results. Treatment with ghrelin during administration of DSS reduced the development of colitis. Morphological features of colonic mucosa exhibited a reduction in the area and deep of mucosal damage. Ghrelin reversed the colitis-induced decrease in blood flow, DNA synthesis, and superoxide dismutase activity in colonic mucosa. These effects were accompanied by a decrease in the colitis-evoked increase in mucosal concentration of interleukin-1β and malondialdehyde. Treatment with ghrelin reversed the DSS-induced reduction in body weight gain. Conclusions. Administration of ghrelin exhibits the preventive effect against the development of DSS-induced colitis. This effect seems to be related to ghrelin’s anti-inflammatory and antioxidative properties.

Dextran sodium sulfate (DSS induces necrotizing enterocolitis-like lesions in neonatal mice.

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Marco Ginzel

Full Text Available Necrotizing enterocolitis (NEC is an inflammatory bowel disease of preterm human newborns with yet unresolved etiology. An established neonatal murine model for NEC employs oral administration of lipopolysaccharides (LPS combined with hypoxia/hypothermia. In adult mice, feeding dextran sodium sulfate (DSS represents a well-established model for experimental inflammatory bowel disease. Here we investigated the effect of DSS administration on the neonatal murine intestine in comparison with the established NEC model.3-day-old C57BL/6J mice were either fed formula containing DSS or LPS. LPS treated animals were additionally stressed by hypoxia/hypothermia twice daily. After 72 h, mice were euthanized, their intestinal tissue harvested and analyzed by histology, qRT-PCR and flow cytometry. For comparison, adult C57BL/6J mice were fed with DSS for 8 days and examined likewise. Untreated, age matched animals served as controls.Adult mice treated with DSS exhibited colonic inflammation with significantly increased Cxcl2 mRNA expression. In contrast, tissue inflammation in neonatal mice treated with DSS or LPS plus hypoxia/hypothermia was present in colon and small intestine as well. Comparative analysis of neonatal mice revealed a significantly increased lesion size and intestinal Cxcl2 mRNA expression after DSS exposure. Whereas LPS administration mainly induced local neutrophil recruitment, DSS treated animals displayed increased monocytes/macrophages infiltration.Our study demonstrates the potential of DSS to induce NEC-like lesions accompanied by a significant humoral and cellular immune response in the small and large intestine of neonatal mice. The new model therefore represents a good alternative to LPS plus hypoxia/hypothermia administration requiring no additional physical stress.

Fast Removal of Citalopram Drug from Waste Water Using Magnetic Nanoparticles Modified with Sodium Dodecyl Sulfate Followed by UV-Spectrometry

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M. Khoeini Sharifabadi

2014-02-01

Full Text Available A simple and sensitive, solid-phase extraction method for the removal of Citalopram drug from waste water has been developed by using magnetic nanoparticles modified with surfactant sodium dodecyl sulfate. These magnetic nanoparticles have shown great adsorptive tendency towards Citalopram drug. The effect of different parameters influencing the extraction efficiency of this drug were investigated and optimized including the pH, amount of the surfactant, contact time and temperature. The extracts were analyzed by ultraviolet spectrophotometry at 239nm. Under these conditions, the related standard deviation (RSD % of the method at two concentrations (5 and 50µg.mL-1 was in the range of (3.14–3.75 % (n = 8. The calibration curve was linear in the range of 2-100 µg.mL-1 of Citalopram drug with a correlation coefficient of >0.99.

Fast Removal of Citalopram Drug from Waste Water Using Magnetic Nanoparticles Modified with Sodium Dodecyl Sulfate Followed by UV-Spectrometry

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M. Khoeini Sharifabadi

2013-04-01

Full Text Available A simple and sensitive, solid-phase extraction method for the removal of Citalopram drug from waste water has been developed by using magnetic nanoparticles modified with surfactant sodium dodecyl sulfate. These magnetic nanoparticles have shown great adsorptive tendency towards Citalopram drug. The effect of different parameters influencing the extraction efficiency of this drug were investigated and optimized including the pH, amount of the surfactant, contact time and temperature. The extracts were analyzed by ultraviolet spectrophotometry at 239nm. Under these conditions, the related standard deviation (RSD % of the method at two concentrations (5 and 50µg.mL-1 was in the range of (3.14–3.75 % (n = 8. The calibration curve was linear in the range of 2-100 µg.mL-1 of Citalopram drug with a correlation coefficient of >0.99.

Reactive extraction of carboxylic acids from apolar hydrocarbons using aqueous solutions of sodium hydrogen carbonate with back-recovery using carbon dioxide under pressure

NARCIS (Netherlands)

Kuzmanovic, B.; Kuipers, N.J.M.; de Haan, A.B.; Kwant, Gerard

2005-01-01

A combination of using an aqueous solution of sodium hydrogen carbonate for forward-extraction of carboxylic acids from a dilute apolar organic solvent, and carbon dioxide under pressure for its back-recovery, is studied. Used in combination, these two steps might provide a technique for the

Swelling and hydrolysis kinetics of Kraft pulp fibers in aqueous 1-butyl-3-methylimidazolium hydrogen sulfate solutions.

Science.gov (United States)

Mao, Jia; Abushammala, Hatem; Pereira, Laura Barcellos; Laborie, Marie-Pierre

2016-11-20

1Butyl-3-methylimidazolium hydrogen sulfate ([Bmim]HSO4) is efficient at extracting cellulose nanocrystals from pulp fibers. To shed some light on the respective contributions of swelling and hydrolysis of pulp fibers by [Bmim]HSO4, the physical, structural and morphological characteristics of hardwood Kraft pulp fibers were monitored under various conditions of temperature, water content and time. Swelling was largely compounded by hydrolysis at the highest temperatures (120°C) as evidenced by mass loss and reduced degree of polymerization (DPn) at this temperature. At 120°C only, water content appeared to play a significant role on the extent of hydrolysis. At this temperature, a heterogeneous kinetic model involving weak links and amorphous regions best described the experimental data. Hydrolysis rates were maximum at 25% water content in the aqueous ionic liquid. Copyright © 2016 Elsevier Ltd. All rights reserved.

Heparan Sulfate and Chondroitin Sulfate Glycosaminoglycans Are Targeted by Bleomycin in Cancer Cells.

Science.gov (United States)

Li, Xiulian; Lan, Ying; He, Yanli; Liu, Yong; Luo, Heng; Yu, Haibo; Song, Ni; Ren, Sumei; Liu, Tianwei; Hao, Cui; Guo, Yunliang; Zhang, Lijuan

2017-01-01

Bleomycin is a clinically used anti-cancer drug that produces DNA breaks once inside of cells. However, bleomycin is a positively charged molecule and cannot get inside of cells by free diffusion. We previously reported that the cell surface negatively charged glycosaminoglycans (GAGs) may be involved in the cellular uptake of bleomycin. We also observed that a class of positively charged small molecules has Golgi localization once inside of the cells. We therefore hypothesized that bleomycin might perturb Golgi-operated GAG biosynthesis. We used stable isotope labeling coupled with LC/MS analysis of GAG disaccharides simultaneously from bleomycin-treated and non-treated cancer cells. To further understand the cytotoxicity of bleomycin and its relationship to GAGs, we used sodium chlorate to inhibit GAG sulfation and commercially available GAGs to compete for cell surface GAG/bleomycin interactions in seven cell lines including CHO745 defective in both heparan sulfate and chondroitin sulfate biosynthesis. we discovered that heparan sulfate GAG was significantly undersulfated and the quantity and disaccharide compositions of GAGs were changed in bleomycin-treated cells in a concentration- and time-dependent manner. We revealed that bleomycin-induced cytotoxicity was directly related to cell surface GAGs. GAGs were targeted by bleomycin both at cell surface and at Golgi. Thus, GAGs might be the biological relevant molecules that might be related to the bleomycin-induced fibrosis in certain cancer patients, a severe side effect with largely unknown molecular mechanism. © 2017 The Author(s). Published by S. Karger AG, Basel.

Hydrogen formation and control under postulated LMFBR accident conditions

International Nuclear Information System (INIS)

Armstrong, G.R.; Wierman, R.W.

1976-09-01

The objective of this study is to experimentally investigate the potential for autoignition and combustion of hydrogen-sodium mixtures which may be produced in LMFBR accidents. The purpose and ultimate usefulness of this work is to provide data that will establish the validity and acceptability of mechanisms inherent to the LMFBR that could either prevent or delay the accumulation of hydrogen gas to less than 4 percent (V) in the Reactor Containment Building (RCB) under accident conditions. The results to date indicate that sodium and sodium-hydrogen mixtures such as may be expected during LMFBR postulated accidents will ignite upon entering an air atmosphere and that the hydrogen present will be essentially all consumed until such time that the oxygen concentration is depleted

Micellar solubilization in strongly interacting binary surfactant systems. [Binary surfactant systems of: dodecyltrimethylammonium chloride + sodium dodecyl sulfate; benzyldimethyltetradecylammonium chloride + tetradecyltrimethylammonium chloride

Energy Technology Data Exchange (ETDEWEB)

Treiner, C. (Universite Pierre et Marie Curie, Paris (France)); Nortz, M.; Vaution, C. (Faculte de Pharmacie de Paris-sud, Chatenay-Malabry (France))

1990-07-01

The apparent partition coefficient P of barbituric acids between micelles and water has been determined in mixed binary surfactant solutions from solubility measurements in the whole micellar composition range. The binary systems chosen ranged from the strongly interacting system dodecyltrimethylammonium chloride + sodium dodecyl sulfate to weakly interacting systems such as benzyldimethyltetradecylammonium chloride + tetradecyltrimethyammonium chloride. In all cases studied, mixed micelle formation is unfavorable to micellar solubilization. A correlation is found between the unlike surfactants interaction energy, as measured by the regular solution parameter {beta} and the solute partition coefficient change upon surfactant mixing. By use of literature data on micellar solubilization in binary surfactant solutions, it is shown that the change of P for solutes which are solubilized by surface adsorption is generally governed by the sign and amplitude of the interaction parameter {beta}.

Determination of chloride and sulphur in sodium by ion chromatography and its application to PFBR sodium samples

International Nuclear Information System (INIS)

Vijayalakshmi, S.; Ushalakshmi, K.

2011-01-01

Analytical method using ion chromatography was developed for the determination of chloride and sulphur in sodium. In this method, sodium was dissolved in water and various sulphur species present in the sample was oxidized to sulphate using hydrogen peroxide. Carbon dioxide gas was passed through the solution to convert sodium hydroxide to carbonate solution. The resulting sample solution was analysed using suppressed Ion chromatography employing carbonate eluent. This method was applied to the analysis of sodium samples procured for prototype fast breeder reactor. (author)

Sodium sampling and impurities determination

International Nuclear Information System (INIS)

Docekal, J.; Kovar, C.; Stuchlik, S.

1980-01-01

Samples may be obtained from tubes in-built in the sodium facility and further processed or they are taken into crucibles, stored and processed later. Another sampling method is a method involving vacuum distillation of sodium, thus concentrating impurities. Oxygen is determined by malgamation, distillation or vanadium balance methods. Hydrogen is determined by the metal diaphragm extraction, direct extraction or amalgamation methods. Carbon is determined using dry techniques involving burning a sodium sample at 1100 degC or using wet techniques by dissolving the sample with an acid. Trace amounts of metal impurities are determined after dissolving sodium in ethanol. The trace metals are concentrated and sodium excess is removed. (M.S.)

Microbial Diversity in Sulfate-Reducing Marine Sediment Enrichment Cultures Associated with Anaerobic Biotransformation of Coastal Stockpiled Phosphogypsum (Sfax, Tunisia

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Hana Zouch

2017-08-01

Full Text Available Anaerobic biotechnology using sulfate-reducing bacteria (SRB is a promising alternative for reducing long-term stockpiling of phosphogypsum (PG, an acidic (pH ~3 by-product of the phosphate fertilizer industries containing high amounts of sulfate. The main objective of this study was to evaluate, for the first time, the diversity and ability of anaerobic marine microorganisms to convert sulfate from PG into sulfide, in order to look for marine SRB of biotechnological interest. A series of sulfate-reducing enrichment cultures were performed using different electron donors (i.e., acetate, formate, or lactate and sulfate sources (i.e., sodium sulfate or PG as electron acceptors. Significant sulfide production was observed from enrichment cultures inoculated with marine sediments, collected near the effluent discharge point of a Tunisian fertilizer industry (Sfax, Tunisia. Sulfate sources impacted sulfide production rates from marine sediments as well as the diversity of SRB species belonging to Deltaproteobacteria. When PG was used as sulfate source, Desulfovibrio species dominated microbial communities of marine sediments, while Desulfobacter species were mainly detected using sodium sulfate. Sulfide production was also affected depending on the electron donor used, with the highest production obtained using formate. In contrast, low sulfide production (acetate-containing cultures was associated with an increase in the population of Firmicutes. These results suggested that marine Desulfovibrio species, to be further isolated, are potential candidates for bioremediation of PG by immobilizing metals and metalloids thanks to sulfide production by these SRB.

Unsteady aspects of sodium-water reaction. Water clearing of sodium containing equipments

International Nuclear Information System (INIS)

Carnevali, Sofia

2012-01-01

Sodium fast Reactor (FSR) is one of the most promising nuclear reactor concepts in the frame of Generation IV Systems to be commercialised in the next decades. One important safety issue about this technology is the highly exothermal chemical reaction of sodium when brought in contact with liquid water. This situation is likely, in particular during decommissioning, when sodium needs to be firstly converted ('destroyed') into non-reactive species. This is achieved by water washing: the major products are then gaseous hydrogen and corrosive soda. Today, such operations are performed in confined chambers to mitigate the consequences of any possible abnormal conditions. It has for long been believed that the main safety problem was the combustion of hydrogen in the surrounding air despite some pioneering works suggested that even without air the reaction could be explosive. It is extremely important to clarify the phenomenology of sodium-water interactions since available knowledge does not allow a robust extrapolation of existing data/model to full scale plants. The primary objective of this work is to identify and assess the details of the phenomenology, especially at the sodium/water interface, to isolate the leading mechanisms and to propose a robust and innovative modelling approach. A large body of yet unreleased experimental data extracted from the files of the French Commissariat a l'Energie Atomique (CEA) was collated and analysed on the basis of 'explosion' physics. Some additional experiments were also performed to fill some gaps, especially about the kinetics of the reaction. The results strongly suggest that the fast expansion of gas producing a blast wave in certain conditions is a kind of vapour explosion. It also appears that any potential hydrogen-air explosion should be strongly mitigated by the large quantity of water vapour emanating also from the reaction zone. The limitations of existing modelling approaches are clearly

Sodium Lauryl Sulfate Stimulates the Generation of Reactive Oxygen Species through Interactions with Cell Membranes.

Science.gov (United States)

Mizutani, Taeko; Mori, Ryota; Hirayama, Misaki; Sagawa, Yuki; Shimizu, Kenji; Okano, Yuri; Masaki, Hitoshi

2016-12-01

Sodium lauryl sulfate (SLS), a representative anionic surfactant, is well-known to induce rough skin following single or multiple topical applications. The mechanism by which SLS induces rough skin is thought to result from the disruption of skin moisture function consisting of NMF and epidermal lipids. However, a recent study demonstrated that topically applied SLS easily penetrates into the living cell layers of the epidermis, which suggests that physiological alterations of keratinocytes might cause the SLS-induced rough skin. This study was conducted to clarify the effects of SLS on keratinocytes to demonstrate the contribution of SLS to the induction of rough skin. In addition, the potentials of other widely used anionic surfactants to induce rough skin were evaluated. HaCaT keratinocytes treated with SLS had increased levels of intracellular ROS and IL-1α secretion. Application of SLS on the surface of a reconstructed epidermal equivalent also showed the increased generation of ROS. Further, SLS-treated cells showed an increase of intracellular calpain activity associated with the increase of intracellular Ca 2+ concentration. The increase of intracellular ROS was abolished by the addition of BAPTA-AM, a specific chelator of Ca 2+ . In addition, IL-1α also stimulated ROS generation by HaCaT keratinocytes. An ESR spin-labeling study demonstrated that SLS increased the fluidity of membranes of liposomes and cells. Together, those results indicate that SLS initially interacts with cell membranes, which results in the elevation of intracellular Ca 2+ influx. Ca 2+ stimulates the secretion of IL-1α due to the activation of calpain, and also increases ROS generation. IL-1α also stimulates ROS generation by HaCaT keratinocytes. We conclude from these results that the elevation of intracellular ROS levels is one of the causes of SLS-induced rough skin. Finally, among the other anionic surfactants tested, sodium lauryl phosphate has less potential to induce rough