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Sample records for balanced salt solution

  1. 21 CFR 864.2875 - Balanced salt solutions or formulations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Balanced salt solutions or formulations. 864.2875 Section 864.2875 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Cell And Tissue Culture Products §...

  2. Balanced versus unbalanced salt solutions: what difference does it make?

    PubMed

    Magder, Sheldon

    2014-09-01

    The infusion of crystalloid solutions is a fundamental part of the management of critically ill patients. These solutions are used to maintain the balance of water and essential electrolytes and replace losses when patients have limited gastrointestinal intake. They also act as carriers for intravenous infusion of medication and red cells. The most commonly used solution, 0.9% saline, has equal concentrations of Na(+) and Cl(-) even though the plasma concentration of Na(+) normally is 40 meq/L higher than that of Cl(-). The use of this fluid thus can produce a hyperchloremic acidosis in a dose-dependent manner, but it is not known whether this has clinical significance. The first part of this article deals with the significance of Na(+) and Cl(-) in normal physiology. This begins with examination of their roles in the regulation of osmolality, acid-base balance, and generation of electrochemical gradients and why the concentration of Cl(-) normally is considerably lower than that of Na(+). The next part deals with how their concentrations are regulated by the gastrointestinal tract and kidney. Based on the physiology, it would seem that solutions in which the concentration of Na(+) is "balanced" by a substance other than Cl(-) would be advantageous. The final part examines the evidence to support that point. There are strong observational data that support the notion that avoiding an elevated Cl(-) concentration or using fluids that reduce the rise in Cl(-) reduces renal dysfunction, infections, and possibly even mortality. However, observational studies only can indicate an association and cannot indicate causality. Unfortunately, randomized trials to date are far too limited to address this crucial issue. What is clear is that appropriate randomized trials will require very large populations. It also is not known whether the important variable is the concentration of Cl(-), the difference in concentrations of Na(+) and Cl(-), or the total body mass of Cl

  3. In vitro corrosion of ZEK100 plates in Hank's Balanced Salt Solution

    PubMed Central

    2012-01-01

    Background In recent years magnesium alloys have been intensively investigated as potential resorbable materials with appropriate mechanical and corrosion properties. Particularly in orthopedic research magnesium is interesting because of its mechanical properties close to those of natural bone, the prevention of both stress shielding and removal of the implant after surgery. Methods ZEK100 plates were examined in this in vitro study with Hank's Balanced Salt Solution under physiological conditions with a constant laminar flow rate. After 14, 28 and 42 days of immersion the ZEK100 plates were mechanically tested via four point bending test. The surfaces of the immersed specimens were characterized by SEM, EDX and XRD. Results The four point bending test displayed an increased bending strength after 6 weeks immersion compared to the 2 week group and 4 week group. The characterization of the surface revealed the presence of high amounts of O, P and Ca on the surface and small Mg content. This indicates the precipitation of calcium phosphates with low solubility on the surface of the ZEK100 plates. Conclusions The results of the present in vitro study indicate that ZEK100 is a potential candidate for degradable orthopedic implants. Further investigations are needed to examine the degradation behavior. PMID:22413949

  4. Periodontal healing of replanted dog teeth stored in Viaspan, milk and Hank's balanced salt solution.

    PubMed

    Trope, M; Friedman, S

    1992-10-01

    This study examined, histologically, periodontal healing and root resorption of replanted dogs teeth stored in Viaspan for different time periods and compared these healing patterns to those after storage in milk or Hank's balanced salt solution (HBSS). Seventy-two beagle incisors were endodontically treated, extracted, randomly divided and placed in Viaspan or milk for 6, 12, 24 and 36 h, and Viaspan or HBSS for 36, 48, 72 and 96 h, after which they were replanted. Four negative control teeth were immediately replanted while four positive controls were allowed to dry for one hour before replantation. All replanted teeth were splinted for 14 days. Two months after replantation the dogs were killed and the teeth histologically examined for healing of the supporting tissues. For Viaspan neither replacement nor inflammatory root resorption was seen after 6 and 12 h storage. A statistically significant rise in the incidence of replacement resorption was seen at 24, 36 and 48 h which decreased again at 72 and 96 h to levels equal to storage for 6 and 12 h. The occurrence of inflammatory root resorption was low and significantly increased only at 48 h after which it decreased significantly again. Viaspan proved superior to milk as a storage medium. Teeth stored in HBSS showed healing results similar to those stored in Viaspan.

  5. Effect of exposure to balanced salt solution upon the hardness of the crystalline lens.

    PubMed

    Tabandeh, H; Karim, A; Thompson, G M

    1998-12-01

    The nucleus confers most of the hardness upon the lens, water content decreases towards the centre of the nucleus and a relative dehydration accompanies increased hardness in some cataractous lenses. It is a possibility that exposure and incubation of the inner layers of the nucleus to balanced salt solution (BSS) can result in the softening of the nucleus. This study aimed to investigate the effect of BSS upon the lens hardness. Nuclear colour element of cataract was graded biomicroscopically. Following extracapsular cataract surgery the lens nucleocortex was divided into two equal parts and each half was allocated randomly to incubation in BSS or air for 5 min before the hardness of each section was assessed by an automated guillotine. Following incubation with BSS the mean force necessary to bisect the lens was 0.50 N and in the control air group the mean force was 0.64 N. The lenses in the BSS-treated group were consistently softer than those in the control group, with a mean softening of 18.3% (P=0.001). The amount of softening was not related to the nuclear colour (P=0.6) or age (P=0.1). Softening of the lens through physical disruption has previously been reported. This study describes the phenomenon of nuclear softening following exposure to BSS, indicating that lens softening can occur through biochemical means.

  6. Absorption of 308-nm excimer laser radiation by balanced salt solution, sodium hyaluronate, and human cadaver eyes

    SciTech Connect

    Keates, R.H.; Bloom, R.T.; Schneider, R.T.; Ren, Q.; Sohl, J.; Viscardi, J.J. )

    1990-11-01

    Absorption of the excimer laser radiations of 193-nm argon fluorine and 308-nm xenon chloride in balanced salt solution, sodium hyaluronate, and human cadaver eyes was measured. The absorption of these materials as considerably different for the two wavelengths; we found that 308-nm light experienced much less absorption than the 193-nm light. The extinction coefficient (k) for 308 nm was k = 0.19/cm for balanced salt solution and k = 0.22/cm for sodium hyaluronate. In contrast to this, the extinction coefficient for 193 nm was k = 140/cm for balanced salt solution and k = 540/cm for sodium hyaluronate. Two 1-day-old human phakic cadaver eyes showed complete absorption with both wavelengths. Using aphakic eyes, incomplete absorption was noted at the posterior pole with 308 nm and complete absorption was noted with 193 nm. The extinction in the anterior part of aphakic eyes (the first 6 mm) was 4.2/cm for 308 nm, meaning that the intensity of the light is reduced by a factor of 10 after traveling the first 5.5 mm. However, we observed that the material in the eye fluoresces, meaning the 308 nm is transformed into other (longer) wavelengths that travel through the total eye with minimal absorption. Conclusions drawn from this experiment are that the use of the 308-nm wavelength may have undesirable side effects, while the use of the 193-nm wavelength should be consistent with ophthalmic use on both the cornea and the lens.

  7. Comparison of soymilk, powdered milk, Hank's balanced salt solution and tap water on periodontal ligament cell survival.

    PubMed

    Moazami, Fariborz; Mirhadi, Hosein; Geramizadeh, Bita; Sahebi, Safoura

    2012-04-01

    The purpose of this study was to evaluate the ability of soymilk, powdered milk, and Hank's balanced salt solution (HBSS) to maintain human periodontal ligament (PDL) cell viability in vitro. PDL cells were obtained from extracted healthy third molars and cultured in Dulbecco's modified Eagles medium (DMEM). The cultures were exposed for 1, 2, 4, and 8 h to experimental solutions (tap water served as negative control and DMEM as positive control) at 37°C. The viable cells were then counted using the trypan blue exclusion technique. Data were analyzed by using one-way anova, post hoc Scheffe and two-way anova test. Statistical analysis showed that HBSS, powdered baby formula, and soymilk maintain cell viability equally well in different periods of times. Tap water cannot keep cells viable as well as other solutions. Soymilk and powdered baby formula can be recommended as suitable storage media for avulsed teeth for up to 8 h.

  8. Fibroblast Viability after Storage at 20 °C in Milk, Hank's Balanced Salt Solution and Coconut Water.

    PubMed

    Souza, Beatriz Dulcineia Mendes de; Alves, Ana Maria Hecke; Santos, Luciane Geanini Pena Dos; Simões, Claudia Maria de Oliveira; Felippe, Wilson Tadeu; Felippe, Mara Cristina Santos

    2016-01-01

    The objective of this study was to evaluate the effectiveness of various storage media at 20 °C in maintaining the viability of human periodontal ligament fibroblasts (HPLF) over time. HPLF were maintained at 20 °C in skim milk (SM), whole milk (WM), freshly prepared Hank's balanced salt solution (HBSS), Save-A-Tooth(r), natural coconut water (NCW), coconut water industrialized (ICW) and tap water (negative control) for 3, 6, 24, 48, 72, 96 and 120 h. Cells maintained in Minimal Essential Medium (MEM-37) at 37 °C served as a positive control. Cell viability was determined by MTT assay. Statistical analysis was performed by Kruskal-Wallis test and Scheffe test (α = 5%). From 24 h, NCW was significantly better in maintaining cell viability than all other tested storage media (p<0.05). SM and WM were significantly better than HBSS for up to 72 h. Save-A-Tooth(r) and ICW were the worst conservation storage media. In conclusion, the effectiveness of the tested storage media to maintain the viability of the periodontal ligament cells was as follows, in a descending order: NCW > MEM-37> SM and IM> HBSS> ICW > Save-A-Tooth(r)> tap water.

  9. Electrochemical Investigations of Polycaprolactone-Coated AZ31 Mg Alloy in Earle's Balance Salt Solution and Conventional Simulated Body Fluid

    NASA Astrophysics Data System (ADS)

    Wilke, Benjamin M.; Zhang, Lei

    2016-06-01

    Polycaprolactone (PCL) coating has been shown to increase the corrosion resistance of magnesium alloys when exposed to a simulated body fluid. A PCL dip coating was applied to AZ31 Mg alloy. Samples were immersed in both Earle's Balance Salt Solution (EBSS) and conventional simulated body fluids (c-SBF) up to 14 days. Microscopic morphology, electrochemical impedance spectroscopy, and potentiodynamic polarization tests were performed to evaluate the corrosion behavior changes of PCL coatings against immersion times in EBSS and c-SBF as compared to the uncoated AZ31 substrate. PCL-coated samples demonstrated improved corrosion resistance compared to bare AZ31 in both EBSS and c-SBF, indicating that the PCL coating exhibited good corrosion protection of AZ31 in simulated body fluid. Samples immersed in EBSS showed significantly higher electrochemical impedance values and slower corrosion progression as compared to the samples in c-SBF, because of the decreased chloride content and CO2 buffering mechanism of the EBSS.

  10. Corrosion performance of MAO coatings on AZ31 Mg alloy in simulated body fluid vs. Earle's Balance Salt Solution

    NASA Astrophysics Data System (ADS)

    Wilke, Benjamin M.; Zhang, Lei; Li, Weiping; Ning, Chengyun; Chen, Cheng-fu; Gu, Yanhong

    2016-02-01

    Earle's Balance Salt Solution (EBSS) provides an alternative to the conventional simulated body fluids (c-SBF) and has been shown to better simulate the corrosion conditions in vivo. In this work, a series of tests were conducted to explore the corrosion performance of MAO-coated AZ31 samples in EBSS vs. c-SBF. Samples were produced by varying MAO process parameters and then immersed up to 21 days in both EBSS and c-SBF. The corrosion rates were evaluated by the electrochemical impedance spectroscopy and potentiodynamic scanning. Scanning electron microscope (SEM) was used to compare the progression of microcracks across the surface of the coatings. The evaluation of cross-sectional thickness showed an increase in MAO coating thickness with the process voltage. MAO samples with a thicker coating generally have higher impedance and lower current density at the initial immersion time point of 0.5 h. Samples in EBSS showed higher initial impedance and lower current density values as compared to c-SBF counterparts for all process groups. Samples in EBSS demonstrated a much slower corrosion rate than c-SBF samples because of the decreased chloride content and CO2 buffering mechanism of the EBSS.

  11. Visual outcomes after balanced salt solution infiltration during lenticule separation in small-incision lenticule extraction for myopic astigmatism.

    PubMed

    Liu, Ting; Zhu, Xiaomin; Chen, Kaijian; Bai, Ji

    2017-07-01

    To evaluate the refractive outcomes of balanced salt solution infiltration during small-incision lenticule extraction (SMILE).This randomized prospective study enrolled 52 patients (104 eyes) with myopic astigmatism. Patients underwent SMILE to correct the myopic astigmatism in Daping Hospital of the Third Military Medical University between January and July 2013. One eye of each patient received traditional SMILE (control group) and the other received a modified SMILE procedure (liquid infiltration group). The corrected distance visual acuity (CDVA), postoperative uncorrected distance visual acuity (UDVA), refraction, wavefront aberration, intraocular pressure (IOP), modulation transfer function (MTF) cut-off frequency, and objective scattering index (OSI) were evaluated.UDVA in the liquid infiltration group was significantly higher than that in the control group at 1 day postoperatively, but not at 1 month after surgery. Moreover, OSI and MTF cut-off frequency in the liquid infiltration group were higher than those in the control group at early follow-up. However, no significant intergroup difference was observed in the OSI and MTF cut-off frequency at 3 months after surgery. In addition, the predictability was better in the liquid infiltration group than in the control group. The changes of horizontal coma in the liquid infiltration group were lesser than those in the control group. However, no intergroup difference was observed in the reduction of IOP at 1 month after surgery.The modified SMILE procedure results in better visual outcomes than did the traditional SMILE procedure when used for treating myopic astigmatism.

  12. Iris reconstruction using autologous iris preserved in cold balanced salt solution for 8 hours in iatrogenic total iridodialysis during cataract surgery: a case report.

    PubMed

    Bang, Seung Pil; Jun, Jong Hwa

    2017-04-04

    A large iris defect or extensive iridodialysis can be an intractable cause of visual disturbance, photophobia, glare, monocular diplopia, or cosmetic deformity. The implantation of an artificial iris substitute could be an effective option, but this can cause a reduction in endothelial cell density. We succeeded in the anatomical restoration of iris tissue that was totally dialyzed out of the eye, and was preserved in cold balanced salt solution for 8 h. Engrafted iris tissue was maintained within the aqueous humor. A 71-year-old man was referred to our clinic for management of an iatrogenic total iridodialysis. The totally dialyzed iris tissue was immediately preserved in sterile cold balanced salt solution and packed in a sterile biopsy bottle that was surrounded with ice cubes. Under general anesthesia, a pars plana vitrectomy was performed to remove the remaining lens cortex and vitreous fiber anterior to the equator. A sulcus-positioned intraocular lens (IOL) was repositioned and fixed by ab externo scleral sutures. Preserved iris tissue was inserted and ironed using both iris spatula and ocular viscoelastic devices. Five-point ab interno scleral sutures were made 1.0 mm posterior to the limbus. The engrafted iris was successfully maintained for 6 months and did not undergo any atrophic change or depigmentation, which may be caused by primary implantation failure due to a blocked blood supply.

  13. Intravenous fluids: balancing solutions.

    PubMed

    Hoorn, Ewout J

    2017-08-01

    The topic of intravenous (IV) fluids may be regarded as "reverse nephrology", because nephrologists usually treat to remove fluids rather than to infuse them. However, because nephrology is deeply rooted in fluid, electrolyte, and acid-base balance, IV fluids belong in the realm of our specialty. The field of IV fluid therapy is in motion due to the increasing use of balanced crystalloids, partly fueled by the advent of new solutions. This review aims to capture these recent developments by critically evaluating the current evidence base. It will review both indications and complications of IV fluid therapy, including the characteristics of the currently available solutions. It will also cover the use of IV fluids in specific settings such as kidney transplantation and pediatrics. Finally, this review will address the pathogenesis of saline-induced hyperchloremic acidosis, its potential effect on outcomes, and the question if this should lead to a definitive switch to balanced solutions.

  14. Electrochromic Salts, Solutions, and Devices

    DOEpatents

    Burrell, Anthony K.; Warner, Benjamin P.; McClesky, T. Mark

    2008-10-14

    Electrochromic salts. Electrochromic salts of dicationic viologens such as methyl viologen and benzyl viologen associated with anions selected from bis(trifluoromethylsulfonyl)imide, bis(perfluoroethylsulfonyl)imide, and tris(trifluoromethylsulfonyl)methide are produced by metathesis with the corresponding viologen dihalide. They are highly soluble in molten quarternary ammonium salts and together with a suitable reductant provide electrolyte solutions that are used in electrochromic windows.

  15. Electrochromic Salts, Solutions, and Devices

    DOEpatents

    Burrell, Anthony K.; Warner, Benjamin P.; McClesky, T. Mark

    2008-11-11

    Electrochromic salts. Electrochromic salts of dicationic viologens such as methyl viologen and benzyl viologen associated with anions selected from bis(trifluoromethylsulfonyl)imide, bis(perfluoroethylsulfonyl)imide, and tris(trifluoromethylsulfonyl)methide are produced by metathesis with the corresponding viologen dihalide. They are highly soluble in molten quarternary ammonium salts and together with a suitable reductant provide electrolyte solutions that are used in electrochromic windows.

  16. Electrochromic salts, solutions, and devices

    DOEpatents

    Burrell, Anthony K.; Warner, Benjamin P.; McClesky,7,064,212 T. Mark

    2006-06-20

    Electrochromic salts. Electrochromic salts of dicationic viologens such as methyl viologen and benzyl viologen associated with anions selected from bis(trifluoromethylsulfonyl)imide, bis(perfluoroethylsulfonyl)imide, and tris(trifluoromethylsulfonyl)methide are produced by metathesis with the corresponding viologen dihalide. They are highly soluble in molten quarternary ammonium salts and together with a suitable reductant provide electrolyte solutions that are used in electrochromic windows.

  17. Hydration patterns and salting effects in sodium chloride solution.

    PubMed

    Li, Weifeng; Mu, Yuguang

    2011-10-07

    The salting effects of 2M sodium chloride electrolyte are studied based on a series of model solutes with properties ranging from hydrophobic to hydrophilic. Generally, hydrophobic solutes will be salted out and hydrophilic solutes will be salted in by NaCl solution. The solvation free energy changes are highly correlated with Kirkwood-Buff integrals. The underlying mechanism resorts to the preferential binding of ions and water to solutes. Our results demonstrate that the salting effect not only depends on the salt's position in Hofmeister series, but also on the solutes' specifics. Taking the hydration free energies of solutes and ions as independent variables, a schematic diagram of salting effects is suggested. The resolved multifaceted salting effects rely on the sensitive balance of the tripartite interaction among solutes, ions, and water.

  18. Hydration patterns and salting effects in sodium chloride solution

    NASA Astrophysics Data System (ADS)

    Li, Weifeng; Mu, Yuguang

    2011-10-01

    The salting effects of 2M sodium chloride electrolyte are studied based on a series of model solutes with properties ranging from hydrophobic to hydrophilic. Generally, hydrophobic solutes will be salted out and hydrophilic solutes will be salted in by NaCl solution. The solvation free energy changes are highly correlated with Kirkwood-Buff integrals. The underlying mechanism resorts to the preferential binding of ions and water to solutes. Our results demonstrate that the salting effect not only depends on the salt's position in Hofmeister series, but also on the solutes' specifics. Taking the hydration free energies of solutes and ions as independent variables, a schematic diagram of salting effects is suggested. The resolved multifaceted salting effects rely on the sensitive balance of the tripartite interaction among solutes, ions, and water.

  19. In vitro comparative evaluation of different storage media (hank's balanced salt solution, propolis, Aloe vera, and pomegranate juice) for preservation of avulsed tooth

    PubMed Central

    Babaji, Prashant; Melkundi, Mahesh; Devanna, Raghu; Suresh, B. S.; Chaurasia, Vishwajit Rampratap; Gopinath, P. V.

    2017-01-01

    Objectives: Prognosis of the avulsed teeth is mostly affected by extraoral dry period and storage medium used to store teeth before reimplantation. However, ability of storage media can affect cell viability and success of treatment. Various storage media were tried with some success. The present study was undertaken to comparatively evaluate the efficacy of hank's balanced salt solution (HBSS), propolis, Aloe vera, and pomegranate juice (PJ) in preserving the vitality of periodontal ligament (PDL) cells of avulsed teeth. Materials and Methods: Fifty orthodontically extracted sound teeth with healthy PDL were selected for the present study. Selected teeth were randomly divided into study groups (10 in each) and 5 each as positive and negative control groups. All the teeth were immersed immediately after extraction into respective storage media. Data were statistically analyzed using IBM SPSS software for Windows, Version 19.0., IBM Corp., Armonk, NY, USA. Analysis of variance and multiple range were done using Tukey's honestly significant difference with level of significance at 5% (P > 0.05). Results: Propolis (285,000 viable cells with standard deviation 4.11028 and standard error of 1.38097) showed more viable PDL cells followed by HBSS, A. vera, and PJ. Conclusion: Propolis, A. vera, and PJ can be used as an alternative tooth storage media. PMID:28435369

  20. Protein aggregation in salt solutions

    PubMed Central

    Kastelic, Miha; Kalyuzhnyi, Yurij V.; Hribar-Lee, Barbara; Dill, Ken A.; Vlachy, Vojko

    2015-01-01

    Protein aggregation is broadly important in diseases and in formulations of biological drugs. Here, we develop a theoretical model for reversible protein–protein aggregation in salt solutions. We treat proteins as hard spheres having square-well-energy binding sites, using Wertheim’s thermodynamic perturbation theory. The necessary condition required for such modeling to be realistic is that proteins in solution during the experiment remain in their compact form. Within this limitation our model gives accurate liquid–liquid coexistence curves for lysozyme and γ IIIa-crystallin solutions in respective buffers. It provides good fits to the cloud-point curves of lysozyme in buffer–salt mixtures as a function of the type and concentration of salt. It than predicts full coexistence curves, osmotic compressibilities, and second virial coefficients under such conditions. This treatment may also be relevant to protein crystallization. PMID:25964322

  1. A balanced view of balanced solutions

    PubMed Central

    2010-01-01

    The present review of fluid therapy studies using balanced solutions versus isotonic saline fluids (both crystalloids and colloids) aims to address recent controversy in this topic. The change to the acid-base equilibrium based on fluid selection is described. Key terms such as dilutional-hyperchloraemic acidosis (correctly used instead of dilutional acidosis or hyperchloraemic metabolic acidosis to account for both the Henderson-Hasselbalch and Stewart equations), isotonic saline and balanced solutions are defined. The review concludes that dilutional-hyperchloraemic acidosis is a side effect, mainly observed after the administration of large volumes of isotonic saline as a crystalloid. Its effect is moderate and relatively transient, and is minimised by limiting crystalloid administration through the use of colloids (in any carrier). Convincing evidence for clinically relevant adverse effects of dilutional-hyperchloraemic acidosis on renal function, coagulation, blood loss, the need for transfusion, gastrointestinal function or mortality cannot be found. In view of the long-term use of isotonic saline either as a crystalloid or as a colloid carrier, the paucity of data documenting detrimental effects of dilutional-hyperchloraemic acidosis and the limited published information on the effects of balanced solutions on outcome, we cannot currently recommend changing fluid therapy to the use of a balanced colloid preparation. PMID:21067552

  2. Coagulation and biochemical effects of balanced salt-based high molecular weight vs saline-based low molecular weight hydroxyethyl starch solutions during the anhepatic period of liver transplantation.

    PubMed

    Ahn, H J; Yang, M; Gwak, M S; Koo, M S; Bang, S R; Kim, G S; Lee, S K

    2008-03-01

    The anhepatic period of liver transplantation is generally marked by a decrease in preload, and the infusion of hydroxyethyl starch (HES) solution is often an effective way to restore volume deficits in non-anaemic patients. However, the infusion of even limited amounts of HES solution during the anhepatic period may result in a worsening coagulopathy. Moreover, lactate-containing HES solution may cause some degree of biochemical derangements in compromised recipients. Therefore, we compared two different types of HES solutions: a balanced salt-based high molecular weight HES solution (670/0.75; high MW group) and a saline-based low molecular weight HES solution (130/0.4; low MW group) with respect to coagulation and biochemical profiles. First, in an in vitro study (n = 48), thromboelastography was performed to determine the effects of two HES solutions on coagulation after diluting (11%) the recipient's blood sample with each HES solution. Second, in an in vivo study, 500 ml of one of the two 6% HES solution was administered to 74 recipients (n = 37, each group) for 30 min after starting the anhepatic period. The coagulation profiles, including thromboelastography, and biochemical profiles were measured before and 30 min after the end of infusion. Less impairment in the thromboelastography profiles and aPTT was observed in the high MW group. A higher calcium concentration and less reduction in platelet count were noted in the high MW group, but lactate accumulation was greater. In conclusion, a balanced salt-based high molecular weight HES solution is a more effective volume replacement during the anhepatic period of liver transplantation with respect to coagulation than a saline-based low molecular weight HES solution, although lactate accumulation is a possible concern.

  3. [Structure and Activity of Fungal Lipases in Bile Salt Solutions].

    PubMed

    Bogdanova, L R; Bakirova, D R; Valiullina, Yu A; Idiyatullin, B Z; Faizullin, D A; Zueva, O S; Zuev, Yu F

    2016-01-01

    The changes in structure and catalytic properties of fungal lipases (Candida rugosa, Rhizomucor miehei, Mucor javanicus) were investigated in micellar solutions of bile salts that differ in hydrophilic-lypophilic balance and reaction medium properties. The methods of circular dichroism and tryptophan fluorescence were applied to estimate the changes in peptide structure within complexes with bile salt micelles. Bile salts do not exert a significant influence on the structure of the enzymes under study: in Rh. miehei and M. javanicus lipases the alpha helix content slightly decreased, the influence of bile salts on the C. rugosa structure was not revealed. Despite negligible structural modifications in the enzymes, in bile salt solutions a considerable change in their catalytic properties was observed: an abrupt decrease in catalytic effectiveness. Substrate-bile salts micelles complex formation was demonstrated by the NMR self-diffusion method. The model of a regulation of fungal lipase activity was proposed.

  4. Solute balance of a maize (Zea mays L.) source leaf as affected by salt treatment with special emphasis on phloem retranslocation and ion leaching.

    PubMed

    Lohaus, G; Hussmann, M; Pennewiss, K; Schneider, H; Zhu, J J; Sattelmacher, B

    2000-10-01

    Strategies for avoiding ion accumulation in leaves of plants grown at high concentration of NaCl (100 mol m(-3)) in the rooting media, i.e. retranslocation via the phloem and leaching from the leaf surface, were quantified for fully developed leaves of maize plants cultivated hydroponically with or without salt, and with or without sprinkling (to induce leaching). Phloem sap, apoplastic fluid, xylem sap, solutes from leaf and root tissues, and the leachate were analysed for carbohydrates, amino acids, malate, and inorganic ions. In spite of a reduced growth rate Na(+) and Cl(-) concentrations in the leaf apoplast remained relatively low (about 4-5 mol m(-3)) under salt treatment. Concentrations of Na(+) and Cl(-) in the phloem sap of salt-treated maize did not exceed 12 and 32 mol m(-3), respectively, and thus remained lower than described for other species. However, phloem transport rates of these ions were higher than reported for other species. The relatively high translocation rate of ions found in maize may be due to the higher carbon translocation rate observed for C(4) plants as opposed to C(3) plants. Approximately 13-36% of the Na(+) and Cl(-) imported into the leaves through the xylem were exported by the phloem. It is concluded that phloem transport plays an important role in controlling the NaCl content of the leaf in maize. Surprisingly, leaching by artificial rain did not affect plant growth. Ion concentrations in the leachate were lower than reported for other plants but increased with NaCl treatment.

  5. SEPARATION OF INORGANIC SALTS FROM ORGANIC SOLUTIONS

    DOEpatents

    Katzin, L.I.; Sullivan, J.C.

    1958-06-24

    A process is described for recovering the nitrates of uranium and plutonium from solution in oxygen-containing organic solvents such as ketones or ethers. The solution of such salts dissolved in an oxygen-containing organic compound is contacted with an ion exchange resin whereby sorption of the entire salt on the resin takes place and then the salt-depleted liquid and the resin are separated from each other. The reaction seems to be based on an anion formation of the entire salt by complexing with the anion of the resin. Strong base or quaternary ammonium type resins can be used successfully in this process.

  6. Salting-out and Salting-in in Polyelectrolyte Solutions

    NASA Astrophysics Data System (ADS)

    Zhang, Pengfei; Wu, Jianzhong; Wang, Zhen-Gang

    The phase behavior of polyelectrolyte (PE) solutions is governed by complicated interplay involving the mixing entropy, excluded volume, chain connectivity, and electrostatic interactions. Here we study the phase behavior of PE solutions in both salt-free condition and with added salt using a liquid-state (LS) theory based thermodynamic model. The LS model accounts or the hard-core repulsion by the Canahan-Starling equation of state, correlations due to chain connectivity by the first-order thermodynamic perturbation theory, and electrostatic correlations by the mean-spherical approximation. In comparison to the prediction from the well-known Voorn-Overbeek theory, the LS model predicts loop-type binodal curves in the salt-PE concentration diagram at temperatures slightly above the critical temperature of PE solution in salt-free case, consistent with the experimental study. The phase separated region shrinks with increasing temperature. Three scenarios of salting-out and salting-in phenomenon are predicted with addition of salts based, depending on the PE concentration.

  7. Ammonia Solubility in High Concentration Salt Solutions

    SciTech Connect

    HEDENGREN, D.C.

    2000-02-01

    Solubility data for ammonia in water and various dilute solutions are abundant in the literature. However, there is a noticeable lack of ammonia solubility data for high salt, basic solutions of various mixtures of salts including those found in many of the Hanford Washington underground waste tanks. As a result, models based on solubility data for dilute salt solutions have been used to extrapolate to high salt solutions. These significant extrapolations need to be checked against actual laboratory data. Some indirect vapor measurements have been made. A more direct approach is to determine the ratio of solubility of ammonia in water to its solubility in high salt solutions. In various experiments, pairs of solutions, one of which is water and the other a high salt solution, are allowed to come to equilibrium with a common ammonia vapor pressure. The ratio of concentrations of ammonia in the two solutions is equal to the ratio of the respective ammonia solubilities (Henry's Law constants) at a given temperature. This information can then be used to refine the models that predict vapor space compositions of ammonia. Ammonia at Hanford is of concern because of its toxicity in the environment and its contribution to the flammability of vapor space gas mixtures in waste tanks.

  8. Coordination chemistry in fused-salt solutions

    NASA Technical Reports Server (NTRS)

    Gruen, D. M.

    1969-01-01

    Spectrophotometric work on structural determinations with fused-salt solutions is reviewed. Constraints placed on the method, as well as interpretation of the spectra, are discussed with parallels drawn to aqueous spectrophotometric curves of the same materials.

  9. Geometric rules of section balancing for salt structures

    SciTech Connect

    Hossack, J.

    1996-12-31

    Restored sections provide not only a measure of the viability of structural interpretations but also have the ability to recreate the geometry of the structures through geologic time. Geologists have known for a long time that section balancing is more difficult in salt structures because of the ability of the salt to flow in and out of the plane of section and also to dissolve and thereby violate constant volume considerations. However, the surrounding sediments generally deform by brittle-plastic processes and are less able to flow out of the plane of a properly chosen section. The pragmatic approach is to restore sections by assuming constant-area conditions for the sediment structures alone and to leave the salt area as gaps that may change in area through time. Most restorations of salt structures suggest that throughout long periods of geologic time, salt remains at or close to the depositional surface and that volume reductions of up to 50% are possible in nature. Salt structures usually involve regional displacements of the salt and its surrounding sediments so that extension in one place has to be balanced by basement extension or cover contraction in another. A key aid to the recognition of contraction and extension is the regional elevation of reference horizons. Generally, salt withdrawal and extensional faulting drop reference beds below regional elevation, whereas salt pillowing, salt sheet formation, and contraction will raise beds above regional elevation. In the Gulf of Mexico, the updip extensional growth faulting and salt withdrawal are balanced by the formation of downdip allochthonous salt sheets and fold and thrust belts, so that the total linear strain across the sediment cover is zero. The extension and contraction are linked by a series of salt and fault welds that lie at several structural levels.

  10. Preparation of sugar-salt solutions.

    PubMed

    de Zoysa, I; Kirkwood, B; Feachem, R; Lindsay-Smith, E

    1984-01-01

    Correct measurement techniques are essential for the preparation of oral rehydration solutions but dangerous or ineffective solutions may also result from the inherent variability of the method and ingredients. This paper describes an experimental study conducted in Zimbabwe to compare the reliability of three methods for measuring sugar and salt in a 750 ml bottle of water: (i) 6 level teaspoons of sugar and half a level teaspoon of salt, (ii) 3 heaped teaspoons of sugar and half a level teaspoon of salt and (iii) 3 level measures of sugar and salt with a double-ended spoon. The teaspoon and 750 ml bottle methods produced reliable results. Heaped teaspoons of sugar gave more reproducible sucrose concentrations than level teaspoons . The double-ended spoon was not more reliable and gave disquietingly high sodium concentrations with refined salt. Under field conditions the level teaspoon method gave more variable results but still within acceptable limits. It is concluded that a domestic teaspoon and a standard 750 ml bottle can be recommended for the preparation of home-based oral rehydration solutions in rural Zimbabwe.

  11. Salting-in and salting-out of water-soluble polymers in aqueous salt solutions.

    PubMed

    Sadeghi, Rahmat; Jahani, Farahnaz

    2012-05-03

    To obtain further experimental evidence for the mechanisms of the salting effect produced by the addition of salting-out or sating-in inducing electrolytes to aqueous solutions of water-soluble polymers, systematic studies on the vapor-liquid equilibria and liquid-liquid equilibria of aqueous solutions of several polymers are performed in the presence of a large series of electrolytes. Polymers are polyethylene glycol 400 (PEG400), polyethylene glycol dimethyl ether 250 (PEGDME250), polyethylene glycol dimethyl ether 2000 (PEGDME2000), and polypropylene glycol 400 (PPG400), and the investigated electrolytes are KCl, NH(4)Cl, MgCl(2), (CH(3))(4)NCl, NaCl, NaNO(3), Na(2)CO(3), Na(2)SO(4), and Na(3)Cit (tri-sodium citrate). Aqueous solutions of PPG400 form aqueous two-phase systems with all the investigated salts; however, other investigated polymers form aqueous two-phase systems only with Na(2)CO(3), Na(2)SO(4), and Na(3)Cit. A relation was found between the salting-out or sating-in effects of electrolyte on the polymer aqueous solutions and the slopes of the constant water activity lines of ternary polymer-salt aqueous solutions, so that, in the case of the salting-out effect, the constant water activity lines had a concave slope, but in the case of the salting-in effects, the constant water activity lines had a convex slope. The effect of temperature, anion of electrolyte, cation of electrolyte, and type and molar mass of polymers were studied and the results interpreted in terms of the solute-water and solute-solute interactions. The salting-out effect results from the formation of ion (specially anion)-water hydration complexes, which, in turn, decreases hydration, and hence, the solubility of the polymer and the salting-in effect results from a direct binding of the cations to the ether oxygens of the polymers.

  12. Oscillations in a Linearly Stratified Salt Solution

    ERIC Educational Resources Information Center

    Heavers, Richard M.

    2007-01-01

    Our physics students like to watch a ball bouncing underwater. They do this by dropping a weighted plastic ball into a 1000-ml cylinder filled with a linearly stratified salt-water solution at room temperature. The ball oscillates and comes to rest at about mid-depth. Its motion is analogous to the damped vertical oscillations of a mass hanging…

  13. Oscillations in a Linearly Stratified Salt Solution

    ERIC Educational Resources Information Center

    Heavers, Richard M.

    2007-01-01

    Our physics students like to watch a ball bouncing underwater. They do this by dropping a weighted plastic ball into a 1000-ml cylinder filled with a linearly stratified salt-water solution at room temperature. The ball oscillates and comes to rest at about mid-depth. Its motion is analogous to the damped vertical oscillations of a mass hanging…

  14. Salt and fluid balance in newborn infants.

    PubMed

    Zetterström, R

    1988-09-01

    About 5 years ago it was widely thought that preterm infants should be supplemented with extra sodium to avoid hyponatremia. It has, however, to be pointed out that VLBW infants during the first postnatal week run a risk of developing hypernatremia which makes it difficult to give general recommendations for sodium supplementation. Since the serum sodium level depends not only upon the balance between sodium intake and sodium excretion but also upon the water balance which may vary depending on the clinical condition of the baby, it seems advisable to monitor the serum sodium level in all preterm infants. Supplementation should be given in case of hyponatremia. In instances of hyponatremia it also has to be considered if the infant due to positive fluid balance has retained fluid in excess of sodium. As a general conclusion the importance of monitoring sodium balance in every preterm infant should be stressed. Disturbances are most likely to occur in VLBW infants and in infants with acute illnesses. The best way of assisting fluid balance is by repeated accurate measurements of the body weight. It should, however, be kept in ming that no reliable methods are available for the measurement of the body weight of a preterm infant who is under intensive care and who cannot be taken out of the incubator. Serum sodium levels may give information of the sodium balance but it has to be stressed that fluid and sodium balances are always interrelated and that it is desirable to have simultaneous estimations of both balances. Excess retention of fluid may be caused primarily by excess retention of sodium or by fluid.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Method for preparing salt solutions having desired properties

    DOEpatents

    Ally, Moonis R.; Braunstein, Jerry

    1994-01-01

    The specification discloses a method for preparing salt solutions which exhibit desired thermodynamic properties. The method enables prediction of the value of the thermodynamic properties for single and multiple salt solutions over a wide range of conditions from activity data and constants which are independent of concentration and temperature. A particular application of the invention is in the control of salt solutions in a process to provide a salt solution which exhibits the desired properties.

  16. Chlorate salts and solutions on Mars

    NASA Astrophysics Data System (ADS)

    Hanley, Jennifer; Chevrier, Vincent F.; Berget, Deanna J.; Adams, Robert D.

    2012-04-01

    Chlorate (ClO3-) is an intermediate oxidation species between chloride (Cl-) and perchlorate (ClO4-), both of which were found at the landing site by the Wet Chemistry Lab (WCL). The chlorate ion is almost as stable as perchlorate, and appears to be associated with perchlorate in most terrestrial reservoirs (e.g. Atacama and Antarctica). It is possible that chlorate contributed to the ion sensor response on the WCL, yet was masked by the strong perchlorate signal. However, very little is known about chlorate salts and their effect on the stability of water. We performed evaporation rate experiments in our Mars simulation chamber, which enabled us to determine the activity of water for various concentrations. From this we constructed solubility diagrams for NaClO3, KClO3, Mg(ClO3)2 and Ca(ClO3)2, and determined the Pitzer parameters for each salt. Chlorate salt eutectic temperatures range from 270 K (KClO3) to 204 K (Mg(ClO3)2). Modeling the addition of chlorate to the initial WCL solutions shows that it precipitates in concentrations comparable to other common salts, such as gypsum and epsomite, and implies that chlorates may play an important role in the wet chemistry on Mars.

  17. Comparative evaluation of maintenance of cell viability of an experimental transport media “coconut water” with Hank's balanced salt solution and milk, for transportation of an avulsed tooth: An in vitro cell culture study

    PubMed Central

    Thomas, Toby; Gopikrishna, Velayutham; Kandaswamy, Deivanayagam

    2008-01-01

    The purpose of this study was to evaluate the efficiency of a new storage medium, coconut water, in comparison with other traditional storage media like Hank's balanced salt solution (HBBS) and milk, in maintaining the viability of an established cell line BHK-21/C13 (baby hamster kidney fibroblasts) using the direct suspension cell culture technique. The storage media tested in the study were divided into three major groups and two control groups - Group A: HBBS, Group B: milk, and Group C: coconut water. The positive and negative controls corresponded to 0-minute and 24-hour dry times respectively. The three groups were then divided into five subgroups, each denoting the storage time periods 15 min, 30 min, 45 min, 60 min and 120 min respectively. The cell line BHK-21/C13 was subcultured and the number of cells was standardized by making a cell suspension using Minimal Essential Medium in five culture plates. One ml of each experimental group (HBBS, milk and coconut water) was added to eight wells of each culture plate. The culture plates containing the cells and the experimental groups were incubated for the respective time periods. The cells were then counted with a Neubauer counting chamber, under light microscope. The results were statistically analyzed using One-way ANOVA and Multiple Range Test using the Tukey-HSD procedure to identify the significant groups at p ≤ 0.05. Within the parameters of this study, it appears that coconut water may be a better alternative to HBSS or milk, in terms of maintaining cell viability. Coconut water can be used as a superior transport medium for avulsed teeth. PMID:20142880

  18. Comparative evaluation of maintenance of cell viability of an experimental transport media "coconut water" with Hank's balanced salt solution and milk, for transportation of an avulsed tooth: An in vitro cell culture study.

    PubMed

    Thomas, Toby; Gopikrishna, Velayutham; Kandaswamy, Deivanayagam

    2008-01-01

    The purpose of this study was to evaluate the efficiency of a new storage medium, coconut water, in comparison with other traditional storage media like Hank's balanced salt solution (HBBS) and milk, in maintaining the viability of an established cell line BHK-21/C13 (baby hamster kidney fibroblasts) using the direct suspension cell culture technique.The storage media tested in the study were divided into three major groups and two control groups - Group A: HBBS, Group B: milk, and Group C: coconut water. The positive and negative controls corresponded to 0-minute and 24-hour dry times respectively.The three groups were then divided into five subgroups, each denoting the storage time periods 15 min, 30 min, 45 min, 60 min and 120 min respectively. The cell line BHK-21/C13 was subcultured and the number of cells was standardized by making a cell suspension using Minimal Essential Medium in five culture plates.One ml of each experimental group (HBBS, milk and coconut water) was added to eight wells of each culture plate. The culture plates containing the cells and the experimental groups were incubated for the respective time periods. The cells were then counted with a Neubauer counting chamber, under light microscope. The results were statistically analyzed using One-way ANOVA and Multiple Range Test using the Tukey-HSD procedure to identify the significant groups at p

  19. Organic ionic salt draw solutions for osmotic membrane bioreactors.

    PubMed

    Bowden, Katie S; Achilli, Andrea; Childress, Amy E

    2012-10-01

    This investigation evaluates the use of organic ionic salt solutions as draw solutions for specific use in osmotic membrane bioreactors. Also, this investigation presents a simple method for determining the diffusion coefficient of ionic salt solutions using only a characterized membrane. A selection of organic ionic draw solutions underwent a desktop screening process before being tested in the laboratory and evaluated for performance using specific salt flux (reverse salt flux per unit water flux), biodegradation potential, and replenishment cost. Two of the salts were found to have specific salt fluxes three to six times lower than two commonly used inorganic draw solutions, NaCl and MgCl(2). All of the salts tested have organic anions with the potential to degrade in the bioreactor as a carbon source and aid in nutrient removal. Results demonstrate the potential benefits of organic ionic salt draw solutions over currently implemented inorganics in osmotic membrane bioreactor systems. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Exact solutions of population balance equation

    NASA Astrophysics Data System (ADS)

    Lin, Fubiao; Flood, Adrian E.; Meleshko, Sergey V.

    2016-07-01

    Population balance equations have been used to model a wide range of processes including polymerization, crystallization, cloud formation, and cell dynamics, but the lack of analytical solutions necessitates the use of numerical techniques. The one-dimensional homogeneous population balance equation with time dependent but size independent growth rate and time dependent nucleation rate is investigated. The corresponding system of equations is solved analytically in this paper.

  1. SOLUTION MINING IN SALT DOMES OF THE GULF COAST EMBAYMENT

    SciTech Connect

    Griswold, G. B.

    1981-02-01

    Following a description of salt resources in the salt domes of the gulf coast embayment, mining, particularly solution mining, is described. A scenario is constructed which could lead to release of radioactive waste stored in a salt dome via inadvertent solution mining and the consequences of this scenario are analyzed.

  2. Solubility of pllutonium in alkaline salt solutions

    SciTech Connect

    Hobbs, D.T.; Edwards, T.B.

    1993-02-26

    Plutonium solubility data from several studies have been evaluated. For each data set, a predictive model has been developed where appropriate. In addition, a statistical model and corresponding prediction intervals for plutonium solubility as a quadratic function of the hydroxide concentration have been developed. Because of the wide range of solution compositions, the solubility of plutonium can vary by as much as three orders of magnitude for any given hydroxide concentration and still remain within the prediction interval. Any nuclear safety assessments that depend on the maximum amount of plutonium dissolved in alkaline salt solutions should use concentrations at least as great as the upper prediction limits developed in this study. To increase the confidence in the prediction model, it is recommended that additional solubility tests be conducted at low hydroxide concentrations and with all of the other solution components involved. To validate the model for application to actual waste solutions, it is recommended that the plutonium solubilities in actual waste solutions be determined and compared to the values predicted by the quadratic model.

  3. Adaptive resolution simulation of salt solutions

    NASA Astrophysics Data System (ADS)

    Bevc, Staš; Junghans, Christoph; Kremer, Kurt; Praprotnik, Matej

    2013-10-01

    We present an adaptive resolution simulation of aqueous salt (NaCl) solutions at ambient conditions using the adaptive resolution scheme. Our multiscale approach concurrently couples the atomistic and coarse-grained models of the aqueous NaCl, where water molecules and ions change their resolution while moving from one resolution domain to the other. We employ standard extended simple point charge (SPC/E) and simple point charge (SPC) water models in combination with AMBER and GROMOS force fields for ion interactions in the atomistic domain. Electrostatics in our model are described by the generalized reaction field method. The effective interactions for water-water and water-ion interactions in the coarse-grained model are derived using structure-based coarse-graining approach while the Coulomb interactions between ions are appropriately screened. To ensure an even distribution of water molecules and ions across the simulation box we employ thermodynamic forces. We demonstrate that the equilibrium structural, e.g. radial distribution functions and density distributions of all the species, and dynamical properties are correctly reproduced by our adaptive resolution method. Our multiscale approach, which is general and can be used for any classical non-polarizable force-field and/or types of ions, will significantly speed up biomolecular simulation involving aqueous salt.

  4. Ion aggregation in high salt solutions. III. Computational vibrational spectroscopy of HDO in aqueous salt solutions

    SciTech Connect

    Choi, Jun-Ho; Lim, Sohee; Chon, Bonghwan; Cho, Minhaeng; Kim, Heejae; Kim, Seongheun

    2015-05-28

    The vibrational frequency, frequency fluctuation dynamics, and transition dipole moment of the O—D stretch mode of HDO molecule in aqueous solutions are strongly dependent on its local electrostatic environment and hydrogen-bond network structure. Therefore, the time-resolved vibrational spectroscopy the O—D stretch mode has been particularly used to investigate specific ion effects on water structure. Despite prolonged efforts to understand the interplay of O—D vibrational dynamics with local water hydrogen-bond network and ion aggregate structures in high salt solutions, still there exists a gap between theory and experiment due to a lack of quantitative model for accurately describing O—D stretch frequency in high salt solutions. To fill this gap, we have performed numerical simulations of Raman scattering and IR absorption spectra of the O—D stretch mode of HDO in highly concentrated NaCl and KSCN solutions and compared them with experimental results. Carrying out extensive quantum chemistry calculations on not only water clusters but also ion-water clusters, we first developed a distributed vibrational solvatochromic charge model for the O—D stretch mode in aqueous salt solutions. Furthermore, the non-Condon effect on the vibrational transition dipole moment of the O—D stretch mode was fully taken into consideration with the charge response kernel that is non-local polarizability density. From the fluctuating O—D stretch mode frequencies and transition dipole vectors obtained from the molecular dynamics simulations, the O—D stretch Raman scattering and IR absorption spectra of HDO in salt solutions could be calculated. The polarization effect on the transition dipole vector of the O—D stretch mode is shown to be important and the asymmetric line shapes of the O—D stretch Raman scattering and IR absorption spectra of HDO especially in highly concentrated NaCl and KSCN solutions are in quantitative agreement with experimental results. We

  5. Selenium mass balance in the Great Salt Lake, Utah

    USGS Publications Warehouse

    Diaz, X.; Johnson, W.P.; Naftz, D.L.

    2009-01-01

    A mass balance for Se in the south arm of the Great Salt Lake was developed for September 2006 to August 2007 of monitoring for Se loads and removal flows. The combined removal flows (sedimentation and volatilization) totaled to a geometric mean value of 2079??kg Se/yr, with the estimated low value being 1255??kg Se/yr, and an estimated high value of 3143??kg Se/yr at the 68% confidence level. The total (particulates + dissolved) loads (via runoff) were about 1560??kg Se/yr, for which the error is expected to be ?? 15% for the measured loads. Comparison of volatilization to sedimentation flux demonstrates that volatilization rather than sedimentation is likely the major mechanism of selenium removal from the Great Salt Lake. The measured loss flows balance (within the range of uncertainties), and possibly surpass, the measured annual loads. Concentration histories were modeled using a simple mass balance, which indicated that no significant change in Se concentration was expected during the period of study. Surprisingly, the measured total Se concentration increased during the period of the study, indicating that the removal processes operate at their low estimated rates, and/or there are unmeasured selenium loads entering the lake. The selenium concentration trajectories were compared to those of other trace metals to assess the significance of selenium concentration trends. ?? 2008 Elsevier B.V.

  6. Selenium mass balance in the Great Salt Lake, Utah.

    PubMed

    Diaz, Ximena; Johnson, William P; Naftz, David L

    2009-03-15

    A mass balance for Se in the south arm of the Great Salt Lake was developed for September 2006 to August 2007 of monitoring for Se loads and removal flows. The combined removal flows (sedimentation and volatilization) totaled to a geometric mean value of 2079 kg Se/yr, with the estimated low value being 1255 kg Se/yr, and an estimated high value of 3143 kg Se/yr at the 68% confidence level. The total (particulates+dissolved) loads (via runoff) were about 1560 kg Se/yr, for which the error is expected to be +/-15% for the measured loads. Comparison of volatilization to sedimentation flux demonstrates that volatilization rather than sedimentation is likely the major mechanism of selenium removal from the Great Salt Lake. The measured loss flows balance (within the range of uncertainties), and possibly surpass, the measured annual loads. Concentration histories were modeled using a simple mass balance, which indicated that no significant change in Se concentration was expected during the period of study. Surprisingly, the measured total Se concentration increased during the period of the study, indicating that the removal processes operate at their low estimated rates, and/or there are unmeasured selenium loads entering the lake. The selenium concentration trajectories were compared to those of other trace metals to assess the significance of selenium concentration trends.

  7. Imidazolium salt ion pairs in solution.

    PubMed

    Stassen, Hubert K; Ludwig, Ralf; Wulf, Alexander; Dupont, Jairton

    2015-06-01

    The formation, stabilisation and reactivity of contact ion pairs of non-protic imidazolium ionic liquids (ILs) in solution are conceptualized in light of selected experimental evidence as well theoretical calculations reported mainly in the last ten years. Electric conductivity, NMR, ESI-MS and IR data as well as theoretical calculations support not only the formation of contact ion pairs in solution, but also the presence of larger ionic and neutral aggregates even when dissolved in solvents with relatively high dielectric constants, such as acetonitrile and DMSO. The presence of larger imidazolium supramolecular aggregates is favoured at higher salt concentrations in solvents of low dielectric constant for ILs that contain shorter N-alkyl side chains associated with anions of low coordination ability. The stability and reactivity of neutral contact species are also dependent on the nature of the anion, imidazolium substituents, and are more abundant in ILs containing strong coordinating anions, in particular those that can form charge transfer complexes with the imidazolium cation. Finally, some ILs display reactivities as contact ion pairs rather than solvent-separated ions.

  8. Solubility of plutonium and uranium in alkaline salt solutions

    SciTech Connect

    Hobbs, D.T.; Edwards, T.B.; Fleischman, S.D.

    1993-02-12

    The solubility of plutonium and uranium in alkaline salt solutions, which will be processed in the In-Tank Precipitation (ITP) process, was investigated to screen for significant factors and interactions among the factors comprising the salt solutions. The factors included in the study were hydroxide, nitrate, nitrite, aluminate, sulfate, carbonate, and temperature. Over the range of factor concentrations studied, the level of hydroxide in the solution is not sufficient alone to predict the resulting concentration of plutonium and uranium in the solution. Other constituents of the salt solution play an important role in determining the amount of plutonium and uranium in solution. Statistical models predicting the plutonium and uranium concentrations over the range of salt solutions investigated are provided.

  9. Pattern Formation in Drying Drops of Polyelectrolyte - Salt Solutions

    NASA Astrophysics Data System (ADS)

    Kaya, Deniz; Belyi, Vladimir A.

    2005-03-01

    We use optical microscopy, AFM, and SEM to investigate salt patterns formed during evaporation of aqueous solutions of sodium poly(styrene sulfonate) and sodium chloride (NaPSS/NaCl). Observed patterns exhibit significantly larger variety than in the simple "drying coffee drop" experiments. We find that varying the concentration ratios of polyelectrolyte/salt solutions leads to formation of qualitatively different patterns, including radially grown salt deposits, concentric rings of salt and other structures. Our results indicate that these patterns are also sensitive to evaporation rate of the droplet. However molecular weight of the polymer appears to have little to no effect on the observed patterns.

  10. Extraction of ethylene glycol from aqueous salt solutions

    NASA Astrophysics Data System (ADS)

    Butyrskaya, E. V.; Belyakova, N. V.; Rozhkova, M. V.; Nechaeva, L. S.

    2012-11-01

    A method is proposed for extracting ethylene glycol from aqueous salt solutions by dialysis through ion-exchange membranes, based on the Donnan exclusion of the electrolyte. Dialysis is performed in the continuous and batch modes. It is found that the batch mode of dialysis is more effective for extracting ethylene glycol from its aqueous salt solutions. The effect of the ionic form of the membrane on ethylene glycol fluxes is explained through computer simulation.

  11. METHOD AND APPARATUS FOR CALCINING SALT SOLUTIONS

    DOEpatents

    Lawroski, S.; Jonke, A.A.; Taecker, R.G.

    1961-10-31

    A method is given for converting uranyl nitrate solution into solid UO/ sub 3/, The solution is sprayed horizontally into a fluidized bed of UO/sub 3/ particles at 310 to 350 deg C by a nozzle of the coaxial air jet type at about 26 psig, Under these conditions the desired conversion takes place, and caking in the bed is avoided.

  12. Optimization of salt concentration in PEG-based crystallization solutions.

    PubMed

    Yamanaka, Mari; Inaka, Koji; Furubayashi, Naoki; Matsushima, Masaaki; Takahashi, Sachiko; Tanaka, Hiroaki; Sano, Satoshi; Sato, Masaru; Kobayashi, Tomoyuki; Tanaka, Tetsuo

    2011-01-01

    Although polyethylene glycol (PEG) is the most widely used precipitant in protein crystallization, the concentration of co-existing salt in the solution has not been well discussed. To determine the optimum salt concentration range, several kinds of protein were crystallized in a 30% PEG 4000 solution at various NaCl concentrations with various pH levels. It was found that, if crystallization occurred, the lowest effective salt concentration depended on the pH of the protein solution and the pI of the protein molecule; that is, higher salt concentrations were required for crystal growth if the difference between pH and pI was increasing. The linear relationship between the charge density of the protein and the ionic strength of the crystallization solution was further verified. These results suggested that the lowest effective concentration of salt in a crystallization solution can be predicted before performing a crystallization experiment. Our results can be a tip for tuning crystallization conditions by the vapor-diffusion method.

  13. SWELLING OF ERYTHROCYTES IN SOLUTIONS OF AMMONIUM SALTS

    PubMed Central

    Schiödt, E.

    1933-01-01

    Two rather simple equations have been derived, which make it possible to express in a single number the result of a series of determinations of the volume of erythrocytes swelling in solutions of ammonium salts. In all experiments made with several combinations of different concentrations of permeating and non-permeating salts, the curves calculated from the equations have covered the points found by experiment. PMID:19872754

  14. Brine rejection from freezing salt solutions: a molecular dynamics study.

    PubMed

    Vrbka, Lubos; Jungwirth, Pavel

    2005-09-30

    The atmospherically and technologically very important process of brine rejection from freezing salt solutions is investigated with atomic resolution using molecular dynamics simulations. The present calculations allow us to follow the motion of each water molecule and salt ion and to propose a microscopic mechanism of brine rejection, in which a fluctuation (reduction) of the ion density in the vicinity of the ice front is followed by the growth of a new ice layer. The presence of salt slows down the freezing process, which leads to the formation of an almost neat ice next to a disordered brine layer.

  15. Hemodynamics and Salt-and-Water Balance Link Sodium Storage and Vascular Dysfunction in Salt-Sensitive Subjects.

    PubMed

    Laffer, Cheryl L; Scott, Robert C; Titze, Jens M; Luft, Friedrich C; Elijovich, Fernando

    2016-07-01

    We investigated 24-hour hemodynamic changes produced by salt loading and depletion in 8 salt-sensitive (SS) and 13 salt-resistant (SR) normotensive volunteers. After salt loading, mean arterial pressure was higher in SS (96.5±2.8) than in SR (84.2±2.7 mm Hg), P<0.01, owing to higher total peripheral resistance in SS (1791±148) than in SR (1549±66 dyn*cm(-5)*s), P=0.05, whereas cardiac output was not different between groups (SS 4.5±0.3 versus SR 4.4±0.2 L/min, not significant). Following salt depletion, cardiac output was equally reduced in both groups. Total peripheral resistance increased 24±6% (P<0.001) in SR, whose mean arterial pressure remained unchanged. In contrast, total peripheral resistance did not change in SS (1±6%, not significant). Thus, their mean arterial pressure was reduced, abolishing the mean arterial pressure difference between groups. SS had higher E/e' ratios than SR in both phases of the protocol. In these 21 subjects and in 32 hypertensive patients, Na(+) balance was similar in SR and SS during salt loading or depletion. However, SR did not gain weight during salt retention (-158±250 g), whereas SS did (819±204), commensurate to iso-osmolar water retention. During salt depletion, SR lost the expected amount of weight for iso-osmolar Na(+) excretion, whereas SS lost a greater amount that failed to fully correct the fluid retention from the previous day. We conclude that SS are unable to modulate total peripheral resistance in response to salt depletion, mirroring their inability to vasodilate in response to salt loading. We suggest that differences in water balance between SS and SR indicate differences in salt-and-water storage in the interstitial compartment that may relate to vascular dysfunction in SS.

  16. Hemodynamics and salt-and-water balance link sodium storage and vascular dysfunction in salt-sensitive subjects

    PubMed Central

    Laffer, Cheryl L; Scott, Robert C; Titze, Jens M; Luft, Friedrich C.; Elijovich, Fernando

    2016-01-01

    We investigated 24-hour hemodynamic changes produced by salt loading and depletion in eight salt-sensitive (SS) and 13 salt-resistant (SR) normotensive volunteers. After salt loading, mean arterial pressure (MAP) was higher in SS (96.5±2.8) than SR (84.2±2.7 mmHg), p<0.01, owing to higher total peripheral resistance (TPR) in SS (1791±148) than SR (1549±66 dyn.cm−5.sec−1), p=0.05, whereas cardiac output (CO) was not different between groups (SS 4.5±0.3 vs SR 4.4±0.2 l/min, ns). Following salt depletion, CO was equally reduced in both groups. TPR increased 24±6% (p<0.001) in SR, whose MAP remained unchanged. In contrast, TPR did not change in SS (1±6%, ns). Thus, their MAP was reduced, abolishing the MAP difference between groups. SS had higher E/e’ ratios than SR in both phases of the protocol. In these 21 subjects and in 32 hypertensive patients, Na+ balance was similar in SR and SS during salt loading or depletion. However, SR did not gain weight during salt retention (−158±250 g), whereas SS did (819±204), commensurate to isoosmolar water retention. During salt depletion, SR lost the expected amount of weight for isoosmolar Na+ excretion, whereas SS lost a greater amount that failed to fully correct the fluid retention from the previous day. We conclude that SS are unable to modulate TPR in response to salt depletion, mirroring their inability to vasodilate in response to salt loading. We suggest that differences in water balance between SS and SR indicate differences in salt-and-water storage in the interstitial compartment that may relate to vascular dysfunction in SS. PMID:27160204

  17. Forces between hydrophobic solids in concentrated aqueous salt solution.

    PubMed

    Mastropietro, Dean J; Ducker, William A

    2012-03-09

    Much research has focused on the discovery and description of long-ranged forces between hydrophobic solids immersed in water. Here we show that the force between high contact-angle solids in concentrated salt solution (1 M KCl) agrees very well with van der Waals forces calculated from Lifshitz theory for separations greater than 5 nm. The hydrophobic solids are octadecyltrichlorosilane-coated glass, with an advancing contact angle of 108°. Thus, in 1 M salt solution, it is unnecessary to invoke the presence of a hydrophobic force at separations greater than 5 nm. Through measurement in salt solution, we avoid the necessity of accounting for large electrostatic forces that frequently occur in pure water and may obscure resolution of other forces.

  18. Infrared spectroscopy of aqueous ionic salt solutions at low concentrations

    NASA Astrophysics Data System (ADS)

    Max, Jean-Joseph; Gessinger, Véronique; van Driessche, Caroline; Larouche, Pascal; Chapados, Camille

    2007-05-01

    The analysis by infrared spectroscopy of aqueous solutions of the binary inorganic salts NaI and NaCl and the ternary salts CaCl2 and BaCl2 at concentrations from 1000to2mM was carried out to complement a previous study done at higher concentrations on nine binary salts (alkali halides) and one ternary salt (MgCl2) [J.-J. Max and C. Chapados, J. Chem. Phys. 115, 2664 (2001)]. These salts are completely ionized in aqueous solutions, forming monoatomic species that do not absorb IR but that perturb the surrounding water, modifying its spectrum. The factor analysis of the spectra revealed that all these salt solutions were composed of two water types: pure water and salt solvated water. The authors obtained pure salt solvated water spectra for all the salts using an extrapolation technique. The water types obtained are constant for the binary and ternary salts down to 2mM. For the binary salts, we determine that 5.0 and 4.0 water molecules are solvated to the Na +-Cl- and Na+-I- ion pairs, respectively. These numbers are the same as that obtained at higher concentrations. For the new ternary salts, we find that 6.0 and 8.0 water molecules are solvated to Ca++-(Cl-)2 and Ba++-(Cl-)2 ion pairs, respectively. These numbers are higher than the four water molecules solvated to Mg++-(Cl-)2 ion pairs determined previously, but show a progression that follows their atomic numbers. These results constitute new experimental results on "simple" systems whose molecular organization is still a matter of debate. The IR method that probes the system at the molecular level is a method different than the macroscopic ones that give the activity coefficients. The IR gives direct observation at the molecular level of the strong ion-water interactions that are often neglected and its water structure not considered in macroscopic methods. The present results and their analysis together with those obtained by other methods will facilitate the determination of the organization of these

  19. Water and salt balance of Great Salt Lake, Utah, and simulation of water and salt movement through the causeway, 1987-98

    USGS Publications Warehouse

    Loving, Brian L.; Miller, Craig W.; Waddell, Kidd M.

    2000-01-01

    The Southern Pacific Transportation Company completed a rock-fill causeway across Great Salt Lake in 1959. The effect of the causeway was to change the water and salt balance of Great Salt Lake by creating two separate but interconnected parts of the lake, with more than 95 percent of freshwater surface inflow entering the lake south of the causeway.The water and salt balance of Great Salt Lake primarily depends on the amount of inflow from tributary streams and the conveyance properties of the causeway that divides the lake into south and north parts. The conveyance properties of the causeway consist of two 15-foot-wide culverts, a 290-foot-wide breach, and permeable rock-fill material.

  20. Protein diffusiophoresis and salt osmotic diffusion in aqueous solutions.

    PubMed

    Annunziata, Onofrio; Buzatu, Daniela; Albright, John G

    2012-10-25

    Diffusion of a solute can be induced by the concentration gradient of another solute in solution. This transport mechanism is known as cross-diffusion. We have investigated cross-diffusion in a ternary protein-salt-water system. Specifically, we measured the two cross-diffusion coefficients for the lysozyme-NaCl-water system at 25 °C and pH 4.5 as a function of protein and salt concentrations by Rayleigh interferometry. One cross-diffusion coefficient characterizes salt osmotic diffusion induced by a protein concentration gradient, and is related to protein-salt thermodynamic interactions as described by the theories of Donnan membrane equilibrium and protein preferential hydration. The other cross-diffusion coefficient characterizes protein diffusiophoresis induced by a salt concentration gradient, and is described as the difference between a preferential-interaction coefficient and a transport parameter. We first relate our experimental results to the protein net charge and the thermodynamic excess of water near the protein surface. We then extract the Stefan-Maxwell diffusion coefficient describing protein-salt interactions in water. We find that the value of this coefficient is negative, contrary to the friction interpretation of Stefan-Maxwell equations. This result is explained by considering protein hydration. Finally, protein diffusiophoresis is quantitatively examined by considering electrophoretic and hydration effects on protein migration and utilized to accurately estimate lysozyme electrophoretic mobility. To our knowledge, this is the first time that protein diffusiophoresis has been experimentally characterized and a protein-salt Stefan-Maxwell diffusion coefficient reported. This work represents a significant contribution for understanding and modeling the effect of concentration gradients in protein-salt aqueous systems relevant to diffusion-based mass-transfer technologies and transport in living systems.

  1. FREEZING POINTS OF ANTI-COAGULANT SALT SOLUTIONS.

    PubMed

    Hitchcock, D I; Dougan, R B

    1935-03-20

    By a method involving equilibration of ice and solution, and analysis of the solution, freezing point depressions of solutions of sodium citrate, oxalate, and fluoride have been determined over the range Delta = 0.45 to 0.65 degrees C. Determinations with sodium chloride solutions have confirmed the accuracy of the method. In each case the freezing point depression is given, within 0.002 degrees C., as a linear function of the concentration. By the use of these linear equations it is possible to prepare a solution of any of these four salts isotonic with a given biological fluid of known freezing point, provided the latter falls within the range studied.

  2. Aggregation behavior of bile salts in aqueous solution.

    PubMed

    Coello, A; Meijide, F; Núñez, E R; Tato, J V

    1996-01-01

    Freezing point depression, delta T/k, and pNa are measured and analyzed for aqueous solutions of trihydroxy (NaTC) and dihydroxy (NaDC and NaTDC) bile salts. The results show the existence of break points in the plot of delta T/k vs molality at 0.018, 0.013, and 0.007 m, respectively, in good agreement with previous published critical micelle concentration values. Above the break point bile salts form aggregates with average aggregation numbers of 2.59 +/- 0.12 (NaTC), 5.82 +/- 0.04 (NaDC), and 5.42 +/- 0.47 (NaTDC). Fractions of bound counterions are also deduced, being close to 0.3 for the three bile salts studied. This indicates that only one counterion is bound for every three monomers in the aggregate. The different structural models published for the bile salt aggregates are discussed.

  3. [Determination of Chloride Salt Solution by NIR Spectroscopy].

    PubMed

    Zhang, Bin; Chen, Jian-hong; Jiao, Ming-xing

    2015-07-01

    Determination of chloride salt solution by near infrared spectrum plays a very important role in Biomedicine. The near infrared spectrum analysis of Sodium chloride, potassium chloride, calcium chloride aqueous solution shows that the concentration change of chloride salt can affect hydrogen bond, resulting in the variation of near infrared spectrum of water. The temperature influence on NIR spectrum has been decreased by choosing reasonable wavelength range and the wavelength where the temperature effects are zero (isosbestic point). Chlorine salt prediction model was established based on partial least squares method and used for predicting the concentration of the chlorine ion. The impact on near infrared spectrum of the cation ionic radius, the number of ionic charge, the complex effect of ionic in water has also discussed in this article and the reason of every factor are analysed. Experimental results show that the temperature and concentration will affect the near-infrared spectrum of the solution, It is found that the effect of temperature plays the dominant role at low concentrations of chlorine salt; rather, the ionic dominates at high concentration. Chloride complexes are formed in aqueous solution, It has an effect on hydrogen bond of water combining with the cations in chlorine salt solution, Comparing different chloride solutions at the same concentration, the destruction effects of chloride complexes and catnions on the hydrogen bond of water increases in the sequences: CaCl2 >NaCl>KC. The modeling result shows that the determination coefficients (R2) = 99.97%, the root mean square error of cross validation (RM- SECV) = 4.51, and the residual prediction deviation (RPD) = 62.7, it meets the daily requirements of biochemical detection accuracy.

  4. Properties of alkali-halide salt solutions about polarizable nanoparticle solutes for different ion models.

    PubMed

    Wynveen, Aaron; Bresme, Fernando

    2010-10-14

    We investigate the distributions of various salts about large hydrophobic polarizable solutes in aqueous electrolyte solutions. The solutes are modeled as nanometer-sized cylindrical objects, a scale relevant to biomolecules and nanomaterials, and particularly high aspect ratio nanoparticles. Interactions, including image charge forces arising from the finite polarizability of the solute, between explicit solvent/ions and the solute are computed explicitly using a molecular dynamics simulation methodology we have recently introduced. Comparisons are made between several salt species and different models of the force fields for each ionic component of the salt. We find evidence that both small cations, Li(+), and large anions, I(-), adsorb at hydrophobic interfaces. Our results indicate that the ion structure about the solute is strongly dependent on the force field investigated, suggesting that ion selectivity is quite sensitive to the respective parameters defining the ion's size and binding energy as well as to the polarizability of the solute.

  5. Chondroitin Sulfate in Solution: Effects of Mono- and Divalent Salts

    PubMed Central

    Horkay, Ferenc; Basser, Peter J.; Hecht, Anne-Marie; Geissler, Erik

    2013-01-01

    Chondroitin sulphate (CS) is a linear sulfated polysaccharide found in cartilage and other tissues in the body. Small angle neutron scattering (SANS) and dynamic light scattering (DLS) measurements are made on semi-dilute CS solutions to determine ion induced changes in the local order of the CS chains and in their dynamic properties. In salt-free CS solutions SANS detects the correlation peak due to local ordering between adjacent chains in which the characteristic interchain distance is d ≈ 57 Å. In both monovalent and divalent salts (NaCl and CaCl2) aligned linear regions are distinguishable corresponding to distance scales ranging from the length of the monomer unit (8 Å) to about 1000 Å. With increasing calcium ion concentration, the scattering intensity increases. Even in the presence of 200 mM CaCl2, however, neither phase separation nor cross-linking occurs. DLS in the CS solutions reveals two characteristic relaxation modes, the fast mode corresponding to the thermal concentration fluctuations. The collective diffusion coefficient D decreases with increasing calcium ion concentration and exhibits a power law function of the single variable c/J, where c is the CS concentration and J is the ionic strength of the salt in the solution. This result implies that the effect of the sodium and calcium ions on the dynamic properties of CS solutions is fully accounted for by the ionic strength. PMID:23814316

  6. Modification of FGD gypsum in hydrothermal mixed salt solution.

    PubMed

    Wu, Xiao-Qin; Wu, Zhong-Biao

    2006-01-01

    A novel utilization way of the sludge from wet calcium-based flue gas desulfurization (FGD) processes has been developed in this paper. This study focused on the conversion of the FGD gypsum into alpha-hemihydrate calcium sulfate by a hydrothermal salt solution method at atmospheric pressure. Experimental study has been carried out in a batch reactor. Qualitative and quantitative analyses were made by DSC/TG thermal analysis, SEM, XRD, metalloscope and chemical analysis. The experimental results showed that the modification of FGD gypsum was controlled by the dissolution and recrystallization mechanisms. With the introduction of FGD gypsum the salt solution was supersaturated, then crystal nucleus of alpha-hemihydrate calcium sulfate were produced in the solution. With the submicroscopic structure of FGD gypsum crystal changed, the crystal nucleus grew up into alpha-hemihydrate calcium sulfate crystals. Thus, the modification of FGD gypsum was fulfilled.

  7. Photoionization of Sodium Salt Solutions in a Liquid Jet

    SciTech Connect

    Grieves, G. A.; Petrik, Nikolay G.; Herring-Captain, J.; Olanrewaju, B.; Aleksandrov, A.; Tonkyn, Russell G.; Barlow, Stephan E.; Kimmel, Gregory A.; Orlando, Thomas M.

    2008-06-05

    A liquid microjet was employed to examine the gas/liquid interface of aqueous sodium halide (Na+X-, X=Cl, Br, I) salt solutions. Laser excitation at 193 nm produced and removed cations of the form H+(H2O)n and Na+(H2O)m from liquid jet surfaces containing either NaCl, NaBr or NaI. The protonated water cluster yield varied inversely with increasing salt concentration, while the solvated sodium ion cluster yield varied by anion type. The distribution of H+(H2O)n at low salt concentration is identical to that observed from low-energy electron irradiated amorphous ice and the production of these clusters can be accounted for using a localized ionization/Coulomb expulsion model. Production of Na+(H2O)m is not accounted for by this model but requires ionization of solvation shell waters and a contact ion/Coulomb expulsion mechanism. The reduced yields of Na+(H2O)m from high concentration (10-2 and 10-1 M) NaBr and NaI solutions indicate a propensity for Br- and I- at the solution surfaces and interfaces. This is supported by the observation of multiphoton induced production and desorption of Br+ and I+ from the 10-2 and 10-1 M solution surfaces.

  8. Fabrication of CPA Salt Pill with Circulating Solution Method

    NASA Astrophysics Data System (ADS)

    Hoshino, A.; Tokoi, K.; Ishisaki, Y.; Shinozaki, K.; McCammon, D.

    2008-05-01

    We report results on fabrication of a Chromium Potassium Alum (CPA) salt pill. CPA is a typical paramagnetic salt used as refrigerant of Adiabatic Demagnetization Refrigerator (ADR) because of its low Curie point, 4 11 mK. We made an test model of CPA salt pill by fast crystallizing method, namely circulating solution between 36°C and 15°C. The crystallizing rate was 0.5 g h-1, and 40 g of CPA crystal was obtained inside a stainless steel cylinder equipped with 160 copper wires. The cooling test was operated utilizing a commercial ADR system. We attached three thermometers and four heaters to the salt pill, in order to measure thermal conductance among different parts of the pill. It is confirmed that our salt pill was cooled down from B/ T=4 T/2 K to 64 mK at zero magnetic field. We suspect the cause of limiting the cooling temperature in the present level to be the dehydration of CPA, non-uniformity of magnetic field, and stainless steel of the pill which has large heat capacity below 0.1 K.

  9. NEUTRON RADIOGRAPHY MEASUREMENT OF SALT SOLUTION ABSORPTION IN MORTAR.

    PubMed

    Lucero, Catherine L; Spragg, Robert P; Bentz, Dale P; Hussey, Daniel S; Jacobson, David L; Weiss, W Jason

    2017-01-01

    Some concrete pavements in the US have recently exhibited premature joint deterioration. It is hypothesized that one component of this damage can be attributed to a reaction that occurs when salt-laden water is absorbed in the concrete and reacts with the matrix. This study examines the absorption of CaCl2 solution in mortar via neutron imaging. Mortar specimens were prepared with water to cement ratios, (w/c), of 0.36, 0.42 and 0.50 by mass and exposed to chloride solutions with concentrations ranging from 0 % to 29.8 % by mass. Depth of fluid penetration and moisture content along the specimen length were determined for 96 h after exposure. At high salt concentration (29.8 %), the sorption rate decreased by over 80 % in all samples. Along with changes in surface tension and viscosity, CaCl2 reacts with the cement paste to produce products (Friedel's salt, Kuzel's salt, or calcium oxychloride) that block pores and reduce absorption.

  10. Carbon Balance and Water Relations of Sorghum Exposed to Salt and Water Stress 1

    PubMed Central

    Richardson, Steven G.; McCree, Keith J.

    1985-01-01

    The daily (24 hour) changes in carbon balance, water loss, and leaf area of whole sorghum plants (Sorghum bicolor L. Moench, cv BTX616) were measured under controlled environment conditions typical of warm, humid, sunny days. Plants were either (a) irrigated frequently with nutrient solution (osmotic potential −0.08 kilojoules per kilogram = −0.8 bar), (b) not irrigated for 15 days, (c) irrigated frequently with moderately saline nutrient (80 millimoles NaCl + 20 millimoles CaCl2·2H2O per kilogram water, osmotic potential −0.56 kilojoules per kilogram), or (d) preirrigated with saline nutrient and then not irrigated for 22 days. Under frequent irrigation, salt reduced leaf expansion and carbon gain, but water use efficiency was increased since the water loss rate was reduced more than the carbon gain. Water stress developed more slowly in the salinized plants and they were able to adjust osmotically by a greater amount. Leaf expansion and carbon gain continued down to lower leaf water potentials. Some additional metabolic cost associated with salt stress was detected, but under water stress this was balanced by the reduced cost of storing photosynthate rather than converting it to new biomass. Reirrigation produced a burst of respiration associated with renewed synthesis of biomass from stored photosynthate. It is concluded that although irrigation of sorghum with moderately saline water inhibits plant growth in comparison with irrigation with nonsaline water, it also inhibits water loss and allows a greater degree of osmotic adjustment, so that the plants are able to continue growing longer and reach lower leaf water potentials between irrigations. PMID:16664521

  11. Effective potentials of Hofmeister salts in aqueous solution

    NASA Astrophysics Data System (ADS)

    Marquina-Carmona, M. A.; Hernández-Contreras, M.

    2017-01-01

    The effective pair interaction potentials of monovalent halide anions and alkali cations in bulk solution of a molecular solvent model were determined using atomistic simulations. These properties result from the microstructure of the ionic liquid which is the main ingredient in the hypernetted chain approach of liquid theory. We used an optimized set of Lennard-Jones parameters that are thermodynamically reliable for bulk phases of the Hofmeister salts.

  12. The chemistry of drying an aqueous solution of salts.

    PubMed

    Takenaka, Norimichi; Takayama, Kayoko; Ojiro, Naofumi; Shimazaki, Wataru; Ohira, Kingo; Soda, Hiroyuki; Suzue, Takahiko; Sadanaga, Yasuhiro; Bandow, Hiroshi; Maeda, Yasuaki

    2009-11-05

    The fate of salts in drying aqueous solution was investigated. In the drying of acidic solutions, weak acid ions and chloride ions combine with protons and evaporate, depending on the proton concentration. In the drying of alkaline solutions, weak acid ions evaporate or remain as salts depending on the ratio of the concentrations of excess nonvolatile cations (the difference between concentrations of nonvolatile cation and nonvolatile anion) to volatile anions defined as DeltaCA. Under neutral and alkaline conditions, the fate of nitrite depends not only on DeltaCA but also on the drying speed. Nitrite is converted to N2, which is formed by reacting nitrite with ammonium (denitrification), NO and NO2, HONO and salts. In urban areas, nitrite and ammonium can appear in high concentrations in dew. HONO in the atmosphere affects the ozone concentration, but dew formation decreases the concentration of HONO. If chemical denitrification occurs, nitrogen species will decrease in the environment, and as a result, the ozone concentration could decrease. Ozone levels show an ozone depression when dew formed, and a Box model simulation showed an ozone depression by decreasing HONO levels.

  13. SODIUM ALUMINOSILICATE FOULING AND CLEANING OF DECONTAMINATED SALT SOLUTION COALESCERS

    SciTech Connect

    Poirier, M; Thomas Peters, T; Fernando Fondeur, F; Samuel Fink, S

    2008-10-28

    During initial non-radioactive operations at the Modular Caustic Side Solvent Extraction Unit (MCU), the pressure drop across the decontaminated salt solution coalescer reached {approx}10 psi while processing {approx}1250 gallons of salt solution, indicating possible fouling or plugging of the coalescer. An analysis of the feed solution and the 'plugged coalescer' concluded that the plugging was due to sodium aluminosilicate solids. MCU personnel requested Savannah River National Laboratory (SRNL) to investigate the formation of the sodium aluminosilicate solids (NAS) and the impact of the solids on the decontaminated salt solution coalescer. Researchers performed developmental testing of the cleaning protocols with a bench-scale coalescer container 1-inch long segments of a new coalescer element fouled using simulant solution. In addition, the authors obtained a 'plugged' Decontaminated Salt Solution coalescer from non-radioactive testing in the MCU and cleaned it according to the proposed cleaning procedure. Conclusions from this testing include the following: (1) Testing with the bench-scale coalescer showed an increase in pressure drop from solid particles, but the increase was not as large as observed at MCU. (2) Cleaning the bench-scale coalescer with nitric acid reduced the pressure drop and removed a large amount of solid particles (11 g of bayerite if all aluminum is present in that form or 23 g of sodium aluminosilicate if all silicon is present in that form). (3) Based on analysis of the cleaning solutions from bench-scale test, the 'dirt capacity' of a 40 inch coalescer for the NAS solids tested is calculated as 450-950 grams. (4) Cleaning the full-scale coalescer with nitric acid reduced the pressure drop and removed a large amount of solid particles (60 g of aluminum and 5 g of silicon). (5) Piping holdup in the full-scale coalescer system caused the pH to differ from the target value. Comparable hold-up in the facility could lead to less effective

  14. Scaling Equations for a Biopolymer in Salt Solution

    NASA Astrophysics Data System (ADS)

    Geissler, Erik; Hecht, Anne-Marie; Horkay, Ferenc

    2007-12-01

    The effect of the simultaneous presence of monovalent and divalent cations on the thermodynamics of polyelectrolyte solutions is an incompletely solved problem. In physiological conditions, combinations of these ions affect structure formation in biopolymer systems. Dynamic light scattering measurements of the collective diffusion coefficient D and the osmotic compressibility of semidilute hyaluronan solutions containing different ratios of sodium and calcium ions are compared with simple polyelectrolyte models. Scaling relationships are proposed in terms of polymer concentration and ionic strength J of the added salt. Differences in the effects of sodium and calcium ions are found to be expressed only through J.

  15. Geotechnical factors and guidelines for storage of compressed air in solution-mined salt cavities

    NASA Astrophysics Data System (ADS)

    Allen, R. D.; Doherty, T. J.; Thoms, R. L.

    1982-05-01

    The state of knowledge about utilization of solution mined salt cavities for CAES including laboratory experiments, numerical modeling, field characterization, solution mining experience, and operating parameters is outlined. Topics evaluated include: cavern geometry and size; long term creep and creep rupture of rock salt; effects of pressure and temperature loading rates; low frequency fatigue; progressive deterioration of salt fabric with possible air penetration; cavern monitoring methods; and salt properties at nonambient conditions. The only CAES operational facility in the world uses two solution mined salt cavern for air storage and is operating successfully. Stability critera for solution mined salt caverns.

  16. Effects of ion exchange on stream solute fluxes in a basin receiving highway deicing salts

    USGS Publications Warehouse

    Shanley, J.B.

    1994-01-01

    At Fever Brook, a 1260-ha forested basin in central Massachusetts, highway deicing salt application increased the solute flux in streamflow by 120% above background flux (equivalent basis) during a 2-yr period. Attempts to isolate the nonsalt component of stream solute fluxes have commonly subtracted salt contributions based on the net Cl flux (Cl output in streamflow minus Cl input in precipitation). In these studies, any net Na flux in excess of the amount needed to balance the net Cl flux has been attributed to weathering. At Fever Brook, however, the net output of Na was less than the net output of Cl, suggesting a loss of Na within the basin. The Na sink was inferred to be cation exchange of Na for Ca and Mg in the soil. A method was developed to quantify the exchange based on a Na budget, which included an independent estimate of the Na flux from weathering. The amount of exchange was apportioned to Ca and Mg based on their relative concentrations in the stream. The background fluxes of Ca and Mg (i.e., those that would occur in the absence of deicing salts) were calculated by subtracting the amounts from ion exchange plus the much smaller direct contributions in deicing salts from the observed fluxes. Ion exchange and direct salt contributions increased the net output fluxes of Ca and Mg, each by 44% above background. In basins that receive deicing salts, failure to account for cation exchange thus may result in an underestimate of the flux of Na from weathering and overestimates of the fluxes of Ca and Mg from weathering.

  17. Precipitation of oppositely charged polyelectrolytes in salt solutions.

    PubMed

    Kudlay, Alexander; Olvera de la Cruz, Monica

    2004-01-01

    We study phase separation in symmetric solutions of weakly charged flexible chains of opposite sign. Precipitation is caused by effective attractions due to charge fluctuations and by short-range attractions between monomers. The contribution from charge fluctuations is computed within the random phase approximation (RPA), which takes into account the connectivity of charges in the polyions. The impenetrability of the ions is accounted for by using a modified Coulomb potential in the RPA. In good solvent conditions the precipitate monotonically swells and eventually dissolves upon addition of salt. However, near the theta-solvent condition, but still in the good solvent, the precipitate can be stable at any salt concentration. Moreover, the density of the precipitate after initial decrease can increase with addition of salt. This effect is a result of redistribution of salt between the precipitate and the supernatant, which is due to an interplay of electrostatic and hardcore interactions. For not too weakly charged polyions the precipitate properties become strongly dependent on temperature even in good solvent conditions.

  18. Introductory lecture: interpreting and predicting Hofmeister salt ion and solute effects on biopolymer and model processes using the solute partitioning model.

    PubMed

    Record, M Thomas; Guinn, Emily; Pegram, Laurel; Capp, Michael

    2013-01-01

    Understanding how Hofmeister salt ions and other solutes interact with proteins, nucleic acids, other biopolymers and water and thereby affect protein and nucleic acid processes as well as model processes (e.g. solubility of model compounds) in aqueous solution is a longstanding goal of biophysical research. Empirical Hofmeister salt and solute "m-values" (derivatives of the observed standard free energy change for a model or biopolymer process with respect to solute or salt concentration m3) are equal to differences in chemical potential derivatives: m-value = delta(dmu2/dm3) = delta mu23, which quantify the preferential interactions of the solute or salt with the surface of the biopolymer or model system (component 2) exposed or buried in the process. Using the solute partitioning model (SPM), we dissect mu23 values for interactions of a solute or Hofmeister salt with a set of model compounds displaying the key functional groups of biopolymers to obtain interaction potentials (called alpha-values) that quantify the interaction of the solute or salt per unit area of each functional group or type of surface. Interpreted using the SPM, these alpha-values provide quantitative information about both the hydration of functional groups and the competitive interaction of water and the solute or salt with functional groups. The analysis corroborates and quantifies previous proposals that the Hofmeister anion and cation series for biopolymer processes are determined by ion-specific, mostly unfavorable interactions with hydrocarbon surfaces; the balance between these unfavorable nonpolar interactions and often-favorable interactions of ions with polar functional groups determine the series null points. The placement of urea and glycine betaine (GB) at opposite ends of the corresponding series of nonelectrolytes results from the favorable interactions of urea, and unfavorable interactions of GB, with many (but not all) biopolymer functional groups. Interaction potentials and

  19. Faraday Discussion 160 Introductory Lecture: Interpreting and Predicting Hofmeister Salt Ion and Solute Effects on Biopolymer and Model Processes Using the Solute Partitioning Model

    PubMed Central

    Record, M. Thomas; Guinn, Emily; Pegram, Laurel; Capp, Michael

    2013-01-01

    Understanding how Hofmeister salt ions and other solutes interact with proteins, nucleic acids, other biopolymers and water and thereby affect protein and nucleic acid processes as well as model processes (e.g solubility of model compounds) in aqueous solution is a longstanding goal of biophysical research. Empirical Hofmeister salt and solute “m-values” (derivatives of the observed standard free energy change for a model or biopolymer process with respect to solute or salt concentration m3) are equal to differences in chemical potential derivatives: m-value = Δ(dμ2/dm3) = Δμ23 which quantify the preferential interactions of the solute or salt with the surface of the biopolymer or model system (component 2) exposed or buried in the process. Using the SPM, we dissect μ23 values for interactions of a solute or Hofmeister salt with a set of model compounds displaying the key functional groups of biopolymers to obtain interaction potentials (called α-values) that quantify the interaction of the solute or salt per unit area of each functional group or type of surface. Interpreted using the SPM, these α-values provide quantitative information about both the hydration of functional groups and the competitive interaction of water and the solute or salt with functional groups. The analysis corroborates and quantifies previous proposals that the Hofmeister anion and cation series for biopolymer processes are determined by ion-specific, mostly unfavorable interactions with hydrocarbon surfaces; the balance between these unfavorable nonpolar interactions and often-favorable interactions of ions with polar functional groups determine the series null points. The placement of urea and glycine betaine (GB) at opposite ends of the corresponding series of nonelectrolytes results from the favorable interactions of urea, and unfavorable interactions of GB, with many (but not all) biopolymer functional groups. Interaction potentials and local-bulk partition coefficients

  20. Solution procedure of residue harmonic balance method and its applications

    NASA Astrophysics Data System (ADS)

    Guo, ZhongJin; Leung, A. Y. T.; Ma, XiaoYan

    2014-08-01

    This paper presents a simple and rigorous solution procedure of residue harmonic balance for predicting the accurate approximation of certain autonomous ordinary differential systems. In this solution procedure, no small parameter is assumed. The harmonic residue of balance equation is separated in two parts at each step. The first part has the same number of Fourier terms as the present order of approximation and the remaining part is used in the subsequent improvement. The corrections are governed by linear ordinary differential equation so that they can be solved easily by means of harmonic balance method again. Three kinds of different differential equations involving general, fractional and delay ordinary differential systems are given as numerical examples respectively. Highly accurate limited cycle frequency and amplitude are captured. The results match well with the exact solutions or numerical solutions for a wide range of control parameters. Comparison with those available shows that the residue harmonic balance solution procedure is very effective for these autonomous differential systems. Moreover, the present method works not only in predicting the amplitude but also the frequency of bifurcated period solution for delay ordinary differential equation.

  1. Solvent effect induced solute damage in an organic inner salt.

    PubMed

    Shui, Min; Jin, Xiao; Li, Zhongguo; Yang, Junyi; Shi, Guang; Zhang, Xueru; Wang, Yuxiao; Yang, Kun; Wei, Tai-huei; Song, Yinglin

    2010-12-20

    Nonlinear absorption of a newly synthesized organic inner salt Ge-150 dissolved in four different solvents (DMF, DMSO, acetonitrile and acetone) is investigated by the Z-scan technique with both nanosecond and picosecond pulses. When pulse energy surpasses a threshold and pulse-to-pulse separation is shorter than a characteristic time, all the four solutions show absorption weakening induced by cross-pulse effects in the picosecond regime. However, only two of them (Ge-150 dissolved in DMF and DMSO) show this weakening in the nanosecond regime. By conducting a simple verification experiment, we verify this absorption weakening is induced by solute damage related to solvent effect rather than solute migration. A simple theoretical model is proposed to interpret the experimental phenomenon.

  2. Simulation of osmotic pressure in concentrated aqueous salt solutions.

    SciTech Connect

    Luo, Y.; Roux, B.; Univ. of Chicago

    2010-01-01

    Accurate force fields are critical for meaningful simulation studies of highly concentrated electrolytes. The ion models that are widely used in biomolecular simulations do not necessarily reproduce the correct behavior at finite concentrations. In principle, the osmotic pressure is a key thermodynamic property that could be used to test and refine force field parameters for concentrated solutions. Here we describe a novel, simple, and practical method to compute the osmotic pressure directly from molecular dynamics (MD) simulation of concentrated aqueous solutions by introducing an idealized semipermeable membrane. Simple models for Na+, K+, and Cl- are tested and calibrated to accurately reproduce the experimental osmotic pressure at high salt concentration, up to the solubility limit of 4-5 M. The methodology is general and can be extended to any type of solute as well as nonadditive polarizable force fields.

  3. Blending Of Radioactive Salt Solutions In Million Gallon Tanks

    SciTech Connect

    Leishear, Robert A.; Lee, Si Y.; Fowley, Mark D.; Poirier, Michael R.

    2012-12-10

    Research was completed at Savannah River National Laboratory (SRNL) to investigate processes related to the blending of radioactive, liquid waste, salt solutions in 4920 cubic meter, 25.9 meter diameter storage tanks. One process was the blending of large salt solution batches (up to 1135 ? 3028 cubic meters), using submerged centrifugal pumps. A second process was the disturbance of a settled layer of solids, or sludge, on the tank bottom. And a third investigated process was the settling rate of sludge solids if suspended into slurries by the blending pump. To investigate these processes, experiments, CFD models (computational fluid dynamics), and theory were applied. Experiments were performed using simulated, non-radioactive, salt solutions referred to as supernates, and a layer of settled solids referred to as sludge. Blending experiments were performed in a 2.44 meter diameter pilot scale tank, and flow rate measurements and settling tests were performed at both pilot scale and full scale. A summary of the research is presented here to demonstrate the adage that, ?One good experiment fixes a lot of good theory?. Experimental testing was required to benchmark CFD models, or the models would have been incorrectly used. In fact, CFD safety factors were established by this research to predict full-scale blending performance. CFD models were used to determine pump design requirements, predict blending times, and cut costs several million dollars by reducing the number of required blending pumps. This research contributed to DOE missions to permanently close the remaining 47 of 51 SRS waste storage tanks.

  4. Blending of Radioactive Salt Solutions in Million Gallon Tanks - 13002

    SciTech Connect

    Leishear, Robert A.; Lee, Si Y.; Fowley, Mark D.; Poirier, Michael R.

    2013-07-01

    Research was completed at Savannah River National Laboratory (SRNL) to investigate processes related to the blending of radioactive, liquid waste, salt solutions in 4920 cubic meter, 25.9 meter diameter storage tanks. One process was the blending of large salt solution batches (up to 1135 - 3028 cubic meters), using submerged centrifugal pumps. A second process was the disturbance of a settled layer of solids, or sludge, on the tank bottom. And a third investigated process was the settling rate of sludge solids if suspended into slurries by the blending pump. To investigate these processes, experiments, CFD models (computational fluid dynamics), and theory were applied. Experiments were performed using simulated, non-radioactive, salt solutions referred to as supernates, and a layer of settled solids referred to as sludge. Blending experiments were performed in a 2.44 meter diameter pilot scale tank, and flow rate measurements and settling tests were performed at both pilot scale and full scale. A summary of the research is presented here to demonstrate the adage that, 'One good experiment fixes a lot of good theory'. Experimental testing was required to benchmark CFD models, or the models would have been incorrectly used. In fact, CFD safety factors were established by this research to predict full-scale blending performance. CFD models were used to determine pump design requirements, predict blending times, and cut costs several million dollars by reducing the number of required blending pumps. This research contributed to DOE missions to permanently close the remaining 47 of 51 SRS waste storage tanks. (authors)

  5. Silica precipitation in acidic solutions: mechanism, pH effect, and salt effect.

    PubMed

    Gorrepati, Elizabeth A; Wongthahan, Pattanapong; Raha, Sasanka; Fogler, H Scott

    2010-07-06

    This study is the first to show that silica precipitation under very acidic conditions ([HCl] = 2-8 M) proceeds through two distinct steps. First, the monomeric form of silica is quickly depleted from solution as it polymerizes to form primary particles approximately 5 nm in diameter. Second, the primary particles formed then flocculate. A modified Smoluchowski equation that incorporates a geometric population balance accurately describes the exponential growth of silica flocs. Variation of the HCl concentration between 2 and 8 M further showed that polymerization to form primary particles and subsequent particle flocculation become exponentially faster with increasing acid concentration. The effect of salt was also studied by adding 1 M chloride salts to the solutions; it was found that salts accelerated both particle formation and growth rates in the order: AlCl(3) > CaCl(2) > MgCl(2) > NaCl > CsCl > no salt. It was also found that ionic strength, over cation identity, determines silica polymerization and particle flocculation rates. This research reveals that precipitation of silica products from acid dissolution of minerals can be studied apart from the mineral dissolution process. Thus, silica product precipitation from mineral acidization follows a two-step process--formation of 5 nm primary particles followed by particle flocculation--which becomes exponentially faster with increasing HCl concentration and with salts accelerating the process in the above order. This result has implications for any study of acid dissolution of aluminosilicate or silicate material. In particular, the findings are applicable to the process of acidizing oil-containing rock formations, a common practice of the petroleum industry where silica dissolution products encounter a low-pH, salty environment within the oil well.

  6. Many segments and few dollars: SALT solutions for ELTs?

    NASA Astrophysics Data System (ADS)

    Buckley, David A. H.; Meiring, Jacobus G.; Swiegers, Jian; Swart, Gerhard P.

    2004-07-01

    The Southern African Large Telescope (SALT) is a little over 18 months away from completion (in early 2005). It is based on the innovative tilted-Arecibo optical analog, first pioneered by the Hobby-Eberly Telescope (HET). By the end of 2003, all major subsystems, including the verification instrument, will be in place and the commissioning of them begun. Tests of a 7-segment subset of the mirror array, including the Shack-Hartmann alignment instrument, the mirror actuators, capacitive edge sensors and active control system has recently started. The first engineering on-sky tests involving the complete light path, from object to detector, have begun. SALT's primary mirror consists of 91 identical segments mounted on a 9 point whiffle tree mount, using three actuators to control tip and tilt, and a foil-type capacitive edge sensor to detect mirror misalignment. These 480 relatively affordable sensors are permanently attached to the segment edges, and are capable of measuring all misalignment modes, including global radius of curvature. This sensing system, used together with a Shack-Hartman wavefront instrument at the center of curvature, controls the primary mirror array, and could be scaled to an array of the size envisaged for an ELT. SALT has developed some innovative designs improvement over the original HET concept. These include a more effective spherical aberration corrector (SAC), interferometric distance sensing and laser auto-collimation of the prime focus payload, the use of newly developed efficient and durable mirror coatings on the SAC optics, and the use of economical low expansion ceramics for the primary mirror segments. These innovative and cost effective solutions used on SALT have potential applications to ELT designs.

  7. Optical Sensor for Characterizing the Phase Transition in Salted Solutions

    PubMed Central

    Claverie, Rémy; Fontana, Marc D.; Duričković, Ivana; Bourson, Patrice; Marchetti, Mario; Chassot, Jean-Marie

    2010-01-01

    We propose a new optical sensor to characterize the solid-liquid phase transition in salted solutions. The probe mainly consists of a Raman spectrometer that extracts the vibrational properties from the light scattered by the salty medium. The spectrum of the O – H stretching band was shown to be strongly affected by the introduction of NaCl and the temperature change as well. A parameter SD defined as the ratio of the integrated intensities of two parts of this band allows to study the temperature and concentration dependences of the phase transition. Then, an easy and efficient signal processing and the exploitation of a modified Boltzmann equation give information on the phase transition. Validations were done on solutions with varying concentration of NaCl. PMID:22319327

  8. Osmotic swelling of polyacrylate hydrogels in physiological salt solutions.

    PubMed

    Horkay, F; Tasaki, I; Basser, P J

    2000-01-01

    The swelling behavior of fully neutralized sodium polyacrylate gels was investigated in aqueous solutions of alkali metal (LiCl, NaCl, KCl, CsCl) and alkaline earth metal salts (CaCl2, SrCl2, BaCl2). The total salt concentration and the ratio of monovalent to divalent cations were varied in the biologically significant range. It is found that the concentrations of both monovalent and divalent cations vary continuously and smoothly in the gel despite the abrupt change in the gel volume. The individual elastic, mixing, and ionic contributions to the free energy of the gel were separately determined as a function of the degree of network swelling to elucidate the thermodynamics of swelling. Shear modulus measurements performed at different Ca2+ concentrations suggest that Ca2+ does not form stable cross-links between the polymer chains. At low and moderate swelling ratios the concentration dependence of the shear modulus follows a power law behavior, G variation of phi n, with n = 0.34 +/- 0.03. At high swelling degrees, however, the shear modulus increases with increasing swelling. The value of the Flory-Huggins interaction parameter, chi, determined from osmotic swelling pressure and shear modulus measurements, strongly depends on the ionic composition of the equilibrium solution and increases with increasing Ca2+ concentration.

  9. Surface Potential of DPPC Monolayers on Concentrated Aqueous Salt Solutions.

    PubMed

    Casper, Clayton B; Verreault, Dominique; Adams, Ellen M; Hua, Wei; Allen, Heather C

    2016-03-03

    The presence and exchange of electrical charges on the surfaces of marine aerosols influence their ability to act as cloud condensation nuclei and play a role in thundercloud electrification. Although interactions exist between surface-active inorganic ions and organic compounds, their role in surface charging of marine aerosols is not well understood. In this study, the surface potential of dipalmitoylphosphatidylcholine (DPPC) monolayers, a zwitterionic phospholipid found in the sea surface microlayer, is measured on concentrated (0.3-2.0 M) chloride salt solutions containing marine-relevant cations (Na(+), K(+), Mg(2+), Ca(2+)) to model and elucidate the electrical properties of organic-covered marine aerosols. Monovalent cations show only a weak effect on the surface potential of DPPC monolayers in the condensed phase compared to water. In contrast, Mg(2+) and Ca(2+) increase the surface potential, indicating different cation binding modes and affinities for the PC headgroup. Moreover, it is found that for divalent chloride salt solutions, the PC headgroup and interfacial water molecules make the largest dipolar contribution to the surface potential. This study shows that for equal charge concentrations, divalent cations impact surface potential of DPPC monolayers more strongly than monovalents likely through changes in the PC headgroup orientation induced by their complexation along with the lesser ordering of interfacial water molecules caused by phosphate group charge screening.

  10. Terahertz echoes reveal the inhomogeneity of aqueous salt solutions

    NASA Astrophysics Data System (ADS)

    Shalit, Andrey; Ahmed, Saima; Savolainen, Janne; Hamm, Peter

    2017-03-01

    The structural and dynamical properties of water are known to be affected by ion solvation. However, a consistent molecular picture that describes how and to what extent ions perturb the water structure is still missing. Here we apply 2D Raman-terahertz spectroscopy to investigate the impact of monatomic cations on the relaxation dynamics of the hydrogen-bond network in aqueous salt solutions. The inherent ability of multidimensional spectroscopy to deconvolute heterogeneous relaxation dynamics is used to reveal the correlation between the inhomogeneity of the collective intermolecular hydrogen-bond modes and the viscosity of a salt solution. Specifically, we demonstrate that the relaxation time along the echo direction t1 = t2 correlates with the capability of a given cation to 'structure' water. Moreover, we provide evidence that the echo originates from the water-water modes, and not the water-cation modes, which implies that cations can structure the hydrogen-bond network to a certain extent.

  11. 21 CFR 864.2875 - Balanced salt solutions or formulations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Cell And Tissue Culture Products § 864.2875... of most cell culture systems. This media component controls for pH, osmotic pressure, energy source...

  12. 21 CFR 864.2875 - Balanced salt solutions or formulations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Cell And Tissue Culture Products § 864.2875... of most cell culture systems. This media component controls for pH, osmotic pressure, energy source...

  13. 21 CFR 864.2875 - Balanced salt solutions or formulations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Cell And Tissue Culture Products § 864.2875... of most cell culture systems. This media component controls for pH, osmotic pressure, energy source...

  14. 21 CFR 864.2875 - Balanced salt solutions or formulations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Cell And Tissue Culture Products § 864.2875... of most cell culture systems. This media component controls for pH, osmotic pressure, energy source...

  15. Movement of Salt and Nitrate in Shallow Groundwater in California's Central Valley - Large Scale Water, Salt, and Nitrate Balance Calculations

    NASA Astrophysics Data System (ADS)

    Dalgish, B. A.; Boyle, D.; Kretsinger Grabert, V. J.

    2013-12-01

    A large-scale analysis of salt and nitrate was performed for the shallow groundwater aquifer of the entire California Central Valley floor (about 20,000 square miles). This analysis combined many different platforms of data in order to complete water and mass balance calculations. Groundwater and surface water quality test data were used in combination with mass loading from a watershed model (the Environmental Protection Agency's Watershed Analysis Risk Management Framework, or WARMF), as well as an integrated hydrologic model that simulates the use and movement of water coupled between the landscape, surface water, and groundwater (the U.S. Geological Survey's Central Valley Hydrologic Model, or CVHM). For this analysis, the Central Valley floor was divided into 22 zones, and the movement of shallow groundwater, surface water, salt, and nitrate was simulated in, out, and between the zones on a quarterly basis for a 20-year simulation period. In this analysis, shallow groundwater is defined by an estimate of the vertical distance water will travel from the water table within 20 years. Fluxes of mass from deep ambient groundwater and ambient surface water quality were estimated from measured concentration data. Quantities of mass were acquired for recharge (from WARMF output) or calculated using concentrations and other water budget components. Flow and volume components were extracted by post-processing CVHM output data. This resulted in a transient water, salt, and nitrate budget for each of the 22 zones. Simulated shallow groundwater concentrations were calculated to investigate water quality trends for the Central Valley. Four zones were identified as areas with the highest concentrations of salt (TDS) in the southwestern portion of the Central Valley; and six zones were identified as areas with the highest nitrate concentrations, mostly in the southeastern portion of the Valley. Additional analyses intended to shift from the large-scale balance calculations to

  16. Water balance and salt losses in competitive football.

    PubMed

    Maughan, Ronald J; Watson, Phillip; Evans, Gethin H; Broad, Nicholas; Shirreffs, Susan M

    2007-12-01

    Fluid balance and sweat electrolyte losses were measured in the players and substitutes engaged in an English Premier League Reserve competitive football match played at an ambient temperature of 6-8 degrees C (relative humidity 50-60%). Intake of water and/or sports drink and urine output were recorded, and sweat composition was estimated from absorbent swabs applied to 4 skin sites for the duration of the game. Body mass was recorded before and after the game. Data were obtained for 22 players (age 21 y, height 180 cm, mass 78 kg) and 9 substitutes (17 y, 181 cm, 72 kg). All were male. Two of the players were dismissed during the game, and none of the substitutes played any part in the game. Mean +/- SD sweat loss of players amounted to 1.68 +/- 0.40 L, and mean fluid intake was 0.84 +/- 0.47 L (n = 20), with no difference between teams. Corresponding values for substitutes, none of whom played in the match, were 0.40 +/- 0.24 L and 0.78 +/- 0.46 L (n = 9). Prematch urine osmolality was 678 +/- 344 mOsm/kg: 11 of the 31 players provided samples with an osmolality of more than 900 mOsm/kg. Sweat sodium concentration was 62 +/- 13 mmol/L, and total sweat sodium loss during the game was 2.4 +/- 0.8 g. These descriptive data show a large individual variability in hydration status, sweat losses, and drinking behaviors in a competitive football match played in a cool environment, highlighting the need for individualized assessment of hydration status to optimize fluid-replacement strategies.

  17. Is Perioperative Fluid and Salt Balance a Contributing Factor in Postoperative Worsening of Obstructive Sleep Apnea?

    PubMed

    Lam, Thach; Singh, Mandeep; Yadollahi, Azadeh; Chung, Frances

    2016-05-01

    An understanding of the potential mechanisms underlying recurrent upper airway collapse may help anesthesiologists better manage patients in the postoperative period. There is convincing evidence in the sleep medicine literature to suggest that a positive fluid and salt balance can worsen upper airway collapse in patients with obstructive sleep apnea through the redistribution of fluid from the legs into the neck and upper airway while supine, in a process known as "rostral fluid shift." According to this theory, during the day the volume from a fluid bolus or from fluid overload states (i.e., heart failure and chronic kidney disease) accumulates in the legs due to gravity, and when a person lies supine at night, the fluid shifts rostrally to the neck, also owing to gravity. The fluid in the neck can increase the extraluminal pressure around the upper airways, causing the upper airways to narrow and predisposing to upper airway collapse. Similarly, surgical patients also incur large fluid and salt balance shifts, and when recovered supine, this may promote fluid redistribution to the neck and upper airways. In this commentary, we summarize the sleep medicine literature on the impact of fluid and salt balance on obstructive sleep apnea severity and discuss the potential anesthetic implications of excessive fluid and salt volume on worsening sleep apnea.

  18. Structures and stability of salt-bridge in aqueous solution.

    PubMed

    Sagarik, Kritsana; Chaiyapongs, Supaporn

    2005-09-01

    Structures and stability of salt-bridges in aqueous solutions were investigated using a complex formed from the guanidinium (Gdm+) and formate (FmO-) ions as a model system. The Test-particle model (T-model) potentials to describe the interactions in the Gdm+-H2O, FmO(-)-H2O and Gdm+-FmO- complexes were constructed, tested and applied in molecular dynamics (MD) simulations of the aqueous solutions at 298 K. The three-dimensional structures and energetic of the hydrogen bond (H-bond) networks of water in the first hydration shells of the Gdm+ and FmO- ions, as well as the Gdm+-FmO- complex, were visualized and analyzed using various probability distribution (PD) maps. The structures of the average potential energy landscapes at the H-bond networks were employed to characterize the stability and dynamic behavior of water molecules in the first hydration shells of the solutes. It was observed that water molecules in the first hydration shell of the close-contact Gdm+-FmO- complex form associated H-bond networks, which introduce a net stabilization effect to the ion-pair, whereas those in the interstitial H-bond network destabilize and break the solvent-separated Gdm+-FmO- complex. The present results showed that, in order to provide complete insights into the structures and stability of ion-pairs in aqueous solutions, explicit water molecules have to be included in the model calculations.

  19. Cloud-point temperatures for lysozyme in electrolyte solutions: effect of salt type, salt concentration and pH.

    PubMed

    Grigsby, J J; Blanch, H W; Prausnitz, J M

    2001-07-24

    Liquid-liquid phase-separation data were obtained for aqueous saline solutions of hen egg-white lysozyme at a fixed protein concentration (87 g/l). The cloud-point temperature (CPT) was measured as a function of salt type and salt concentration to 3 M, at pH 4.0 and 7.0. Salts used included those from mono and divalent cations and anions. For the monovalent cations studied, as salt concentration increases, the CPT increases. For divalent cations, as salt concentration rises, a maximum in the CPT is observed and attributed to ion binding to the protein surface and subsequent water structuring. Trends for sulfate salts were dramatically different from those for other salts because sulfate ion is strongly hydrated and excluded from the lysozyme surface. For anions at fixed salt concentration, the CPT decreases with rising anion kosmotropic character. Comparison of CPTs for pH 4.0 and 7.0 revealed two trends. At low ionic strength for a given salt, differences in CPT can be explained in terms of repulsive electrostatic interactions between protein molecules, while at higher ionic strength, differences can be attributed to hydration forces. A model is proposed for the correlation and prediction of the CPT as a function of salt type and salt concentration. NaCl was chosen as a reference salt, and CPT deviations from that of NaCl were attributed to hydration forces. The Random Phase Approximation, in conjunction with a square-well potential, was used to calculate the strength of protein-protein interactions as a function of solution conditions for all salts studied.

  20. Balanced crystalloid compared with balanced colloid solution using a goal-directed haemodynamic algorithm.

    PubMed

    Feldheiser, A; Pavlova, V; Bonomo, T; Jones, A; Fotopoulou, C; Sehouli, J; Wernecke, K-D; Spies, C

    2013-02-01

    Controversy exists regarding the optimal i.v. fluids for use with a goal-directed haemodynamic algorithm. In a double-blind pilot study, we randomly assigned 50 patients with primary ovarian cancer undergoing cytoreductive surgery to receive either balanced crystalloid or balanced starch (HES, 130/0.4, 6%) solutions up to the dose limit (50 ml kg(-1)). Fluids were administered to optimize stroke volume measured by oesophageal Doppler within a goal-directed haemodynamic algorithm. Baseline subject characteristics were similar in both groups. The balanced HES solution maintained stroke volume (P=0.012) better with administration of less fluid. Subjects in the colloid group reached the dose limits of the study medication less frequently (92% vs 62%, P=0.036) and later (2:26 vs 3:33 h, P=0.006) and also required less transfusion of fresh-frozen plasma units (6.0 vs 3.5 units, P=0.035) compared with the crystalloid group. Intra- and postoperative urine output and perioperative plasma levels of creatinine and neutrophil gelatinase-associated lipocalin as renal injury marker were similar in both groups. No differences in the length of intensive care unit and hospital stay were found. Using a goal-directed haemodynamic algorithm to optimize stroke volume, a balanced HES solution is associated with better haemodynamic stability and reduced need for fresh-frozen plasma. There were no signs of renal impairment by colloid solutions when fluid administration is targeted to optimize cardiac preload.

  1. Collapse of sodium polyacrylate chains in calcium salt solutions

    NASA Astrophysics Data System (ADS)

    Schweins, R.; Huber, K.

    The sodium salt of polyacrylic acid (NaPA) precipitates in the presence of Ca^{2+}-ions. This phase behaviour can be represented by a phase diagram where the critical NaPA concentration is plotted versus the critical Ca^{2+} concentration resulting in a straight line as a phase boundary. The location of this phase boundary is influenced by the presence of an inert monovalent salt like NaCl. The present contribution focuses on the coil dimensions of NaPA chains in dilute aqueous solution corresponding to the one phase region of such a phase diagram. A variety of parameters with which the size and shape of the polyelectrolyte chains can be modulated are revealed. Approaching the phase boundary by decreasing the NaPA concentration at a constant Ca^{2+} content leads to a collapse of the NaPA chains. Combined static and dynamic light scattering suggests a compact spherical shape as the final state of this transition, both in 0.1 M NaCl and in 0.01 M NaCl. In the lower NaCl concentration, indication is presented for the existence of a cigar or pearl necklace like intermediate. Most strikingly, the collapsed chains can be reexpanded by increasing the concentration of inert NaCl at constant content of NaPA and Ca^{2+}. Clearly, excessive Na+-ions displace the Ca^{2+}-ions from the NaPA chains.

  2. Raman spectroscopic study of the conformation of dicarboxylic acid salts in aqueous solutions

    NASA Astrophysics Data System (ADS)

    Fukushima, Kunio; Watanabe, Toshiaki; Umemura, Matome

    1986-08-01

    It is already known that the molecules of long chain monocarboxylic acid salts have a tendency to form micelles in aqueous solutions, the molecular chain taking the all- trans zigzag structure. However it is considered difficult for dicarboxylic acid salts to adopt the same structure as the monocarboxylic acid salts as they have two carboxyl groups, one on each end of the molecular chain. Therefore, a special structure is expected to exist for dicarboxylic acid salts in aqueous solution. In order to examine this, Raman spectra of suberic acid salt and azelaic acid salt in aqueous solution were measured and the normal vibrational calculation carried out, showing that dicarboxylic acid salts have a helical structure in aqueous solution.

  3. Effect of inorganic salts on crystallization of poly(ethylene glycol) in frozen solutions.

    PubMed

    Izutsu, Ken-ichi; Aoyagi, Nobuo

    2005-01-06

    The effect of inorganic salts on eutectic crystallization of poly(ethylene glycol) (PEG) 1500-20,000 in frozen solution was studied to model the polymer and inorganic salt interaction in freeze-dried formulations. Thermal analysis of an aqueous PEG 3000 solution showed a eutectic PEG crystallization exotherm at approximately -47 degrees C and a subsequent PEG crystal melting endotherm at -14.9 degrees C. Addition of sodium chloride prevented the PEG crystallization in the freeze-concentrated solution surrounding ice crystals. Higher concentration NaCl was required to retain higher molecular weight PEG in the amorphous state. Various inorganic salts prevented the PEG crystallization to varying degrees depending mainly on the position of the anion in the Hofmeister's lyotropic series. Some salting-in and 'intermediate' salts (NaSCN, NaI, NaBr, NaCl, LiCl, KCl, and RbCl) inhibited the crystallization of PEG 7500 in frozen solutions. On the other hand, salting-out salts (NaH2PO4, Na2HPO4, Na2SO4, and NaF) did not show an apparent effect on the PEG crystallization. Some salting-out salts induced PEG crystallization in PEG and sucrose combination frozen solutions. The varying abilities of salts to prevent the PEG crystallization in frozen solutions strongly suggested that the solutes had different degrees of miscibility in the freeze-concentrates.

  4. Effects of subfornical organ extracts on salt-water balance in the rat

    NASA Technical Reports Server (NTRS)

    Summy-Long, J. Y.; Crawford, I. L.; Severs, W. B.

    1976-01-01

    The subfornical organ (SFO) is a circumventricular structure located at the junction of the lamina terminalis and the tela choroidea of the third cerebral ventricle. SFO is histologically regarded as a neurosecretory structure, although the physiological effects or biochemical nature of such secretions are not yet ascertained. Results are presented for an experimental study designed to determine whether SFO extracts alter parameters associated with salt-water balance in the rat. The data obtained support the conclusion that SFO contains some water-soluble substance(s), easily released by incubation, dialyzable and heat stable, which influences the salt-water balance after injection into ventricular cerebrospinal fluid. Whether other brain tissues or plasma contains the same or similar material is not yet convincingly established. The observation that one or more active constituents are easily released from SFO upon incubation in potassium-enriched medium may be of value.

  5. Effects of subfornical organ extracts on salt-water balance in the rat

    NASA Technical Reports Server (NTRS)

    Summy-Long, J. Y.; Crawford, I. L.; Severs, W. B.

    1976-01-01

    The subfornical organ (SFO) is a circumventricular structure located at the junction of the lamina terminalis and the tela choroidea of the third cerebral ventricle. SFO is histologically regarded as a neurosecretory structure, although the physiological effects or biochemical nature of such secretions are not yet ascertained. Results are presented for an experimental study designed to determine whether SFO extracts alter parameters associated with salt-water balance in the rat. The data obtained support the conclusion that SFO contains some water-soluble substance(s), easily released by incubation, dialyzable and heat stable, which influences the salt-water balance after injection into ventricular cerebrospinal fluid. Whether other brain tissues or plasma contains the same or similar material is not yet convincingly established. The observation that one or more active constituents are easily released from SFO upon incubation in potassium-enriched medium may be of value.

  6. Balanced sediment fluxes in southern California’s Mediterranean-climate zone salt marshes

    USGS Publications Warehouse

    Rosencranz, Jordan A.; Ganju, Neil K.; Ambrose, Richard F.; Brosnahan, Sandra M.; Dickhudt, Patrick J.; Guntenspergen, Glenn R.; MacDonald, Glen M.; Takekawa, John Y.; Thorne, Karen M.

    2016-01-01

    Salt marsh elevation and geomorphic stability depends on mineral sedimentation. Many Mediterranean-climate salt marshes along southern California, USA coast import sediment during El Niño storm events, but sediment fluxes and mechanisms during dry weather are potentially important for marsh stability. We calculated tidal creek sediment fluxes within a highly modified, sediment-starved, 1.5-km2 salt marsh (Seal Beach) and a less modified 1-km2marsh (Mugu) with fluvial sediment supply. We measured salt marsh plain suspended sediment concentration and vertical accretion using single stage samplers and marker horizons. At Seal Beach, a 2014 storm yielded 39 and 28 g/s mean sediment fluxes and imported 12,000 and 8800 kg in a western and eastern channel. Western channel storm imports offset 8700 kg exported during 2 months of dry weather, while eastern channel storm imports augmented 9200 kg imported during dry weather. During the storm at Mugu, suspended sediment concentrations on the marsh plain increased by a factor of four; accretion was 1–2 mm near creek levees. An exceptionally high tide sequence yielded 4.4 g/s mean sediment flux, importing 1700 kg: 20 % of Mugu’s dry weather fluxes. Overall, low sediment fluxes were observed, suggesting that these salt marshes are geomorphically stable during dry weather conditions. Results suggest storms and high lunar tides may play large roles, importing sediment and maintaining dry weather sediment flux balances for southern California salt marshes. However, under future climate change and sea level rise scenarios, results suggest that balanced sediment fluxes lead to marsh elevational instability based on estimated mineral sediment deficits.

  7. Balanced Sediment Fluxes in Southern California's Mediterranean-climate Zone Salt Marshes

    NASA Astrophysics Data System (ADS)

    Rosencranz, J. A.; Dickhudt, P.; Ganju, N. K.; Thorne, K.; Takekawa, J.; Ambrose, R. F.; Guntenspergen, G. R.; Brosnahan, S.; MacDonald, G. M.

    2015-12-01

    Salt marsh elevation and geomorphic stability depends on mineral sedimentation. Many southern California, USA salt marshes import sediment during El Niño storm events, but sediment fluxes and mechanisms during dry weather are also potentially important for marsh stability. We calculated tidal creek sediment fluxes within a sediment starved 1.5 km2 salt marsh (Seal Beach) and a less modified 1 km2 marsh (Mugu) with a watershed sediment supply. We measured salt marsh plain suspended sediment concentration and vertical accretion using single stage samplers and marker horizons. At Seal Beach, a 2014 storm yielded 39 and 28 g/s mean sediment fluxes and imported 12000 and 8800 kg in a western channel. This offset 8700 kg export during two months of dry weather, while landward net fluxes in the eastern channel accounted for 33% of the import. During the storm, suspended sediment concentrations on the marsh plain increased by a factor of four; accretion was 1-2 mm near creek levees. An exceptionally high tide sequence at Mugu yielded 4.4 g/s mean sediment flux, importing 1700 kg, accounting for 20% of dry weather fluxes. Overall, low sediment fluxes were observed, suggesting that these salt marshes are currently geomorphically stable. Our results suggest that storms and exceptionally high lunar tides may play large roles, importing sediment and maintaining dry weather sediment flux balances for southern California salt marshes. However, under future climate change and sea-level rise scenarios, results suggest that balanced sediment fluxes may lead to marsh elevational instability, based on estimated mineral sediment deficits.

  8. Balanced-Viscosity solutions for multi-rate systems

    NASA Astrophysics Data System (ADS)

    Mielke, Alexander; Rossi, Riccarda; Savaré, Giuseppe

    2016-06-01

    Several mechanical systems are modeled by the static momentum balance for the displacement u coupled with a rate-independent flow rule for some internal variable z. We consider a class of abstract systems of ODEs which have the same structure, albeit in a finite-dimensional setting, and regularize both the static equation and the rate-independent flow rule by adding viscous dissipation terms with coefficients εα and ε, where 0 < ε « 1 and α > 0 is a fixed parameter. Therefore for α ≠ 1 u and z have different relaxation rates. We address the vanishing-viscosity analysis as ε ↓ 0 of the viscous system. We prove that, up to a subsequence, (reparameterized) viscous solutions converge to a parameterized curve yielding a Balanced Viscosity solution to the original rate-independent system, and providing an accurate description of the system behavior at jumps. We also give a reformulation of the notion of Balanced Viscosity solution in terms of a system of subdifferential inclusions, showing that the viscosity in u and the one in z are involved in the jump dynamics in different ways, according to whether α > 1, α =1, and α є (0,1).

  9. The effect of divalent salt in chondroitin sulfate solutions

    SciTech Connect

    Aranghel, D.; Badita, C. R.; Radulescu, A.; Moldovan, L.; Craciunescu, O.; Balasoiu, M.

    2016-03-25

    Chondroitin-4 sulfate (CS4) is the main glycosaminoglycan extracted from bovine trachea. CS4 play an important role in osteoarthritis treatment, anticoagulant activity, reduces the degradation of cartilage matrix components, reduces necrosis and apoptosis of chondrocytes and reduces the activity of collagenase. Chondroitin sulfate is also responsible for proteoglycans degradation. Chondroitin sulfate can bind calcium ions with different affinities, depending on their sulfation position. The purpose of this study was to determine the structural properties and the influence of Ca{sup 2+} cations. We carried out measurements on CS4 solutions and mixtures of liquid CS4 with Ca{sup 2+} by Small-Angle Neutron Scattering (SANS). CS4 have a mass fractal behavior and the addition of a salt (CaCl{sub 2}) in CS4 solutions generates the appearance of a correlation peak due to local ordering between adjacent chains with inter-chain distances between 483 Å and 233 Å for a calcium concentration of 0.01% w/w.

  10. The effect of divalent salt in chondroitin sulfate solutions

    NASA Astrophysics Data System (ADS)

    Aranghel, D.; Badita, C. R.; Radulescu, A.; Moldovan, L.; Craciunescu, O.; Balasoiu, M.

    2016-03-01

    Chondroitin-4 sulfate (CS4) is the main glycosaminoglycan extracted from bovine trachea. CS4 play an important role in osteoarthritis treatment, anticoagulant activity, reduces the degradation of cartilage matrix components, reduces necrosis and apoptosis of chondrocytes and reduces the activity of collagenase. Chondroitin sulfate is also responsible for proteoglycans degradation. Chondroitin sulfate can bind calcium ions with different affinities, depending on their sulfation position. The purpose of this study was to determine the structural properties and the influence of Ca2+ cations. We carried out measurements on CS4 solutions and mixtures of liquid CS4 with Ca2+ by Small-Angle Neutron Scattering (SANS). CS4 have a mass fractal behavior and the addition of a salt (CaCl2) in CS4 solutions generates the appearance of a correlation peak due to local ordering between adjacent chains with inter-chain distances between 483 Å and 233 Å for a calcium concentration of 0.01% w/w.

  11. Excess entropy of water in a supercooled solution of salt

    NASA Astrophysics Data System (ADS)

    Gallo, P.; Corradini, D.; Rovere, M.

    2011-12-01

    We consider the relationship between the excess entropy and anomalies of water. We investigate by molecular dynamics simulations the thermodynamic region of supercooled water and a supercooled aqueous solution with NaCl at a salt concentration of 0.67 mol kg-1. The TIP4P potential model displays, as already established, in pure water and in solution a phase diagram with a liquid-liquid critical point. We explore how the two-body excess entropy calculated from the radial distribution functions is an indicator of density and structural anomalies of supercooled liquid water, both in the pure system and in the NaCl(aq). The two-body excess entropy shows a peculiar behaviour associated with the density anomaly and structural changes in water as revealed by the radial distribution functions. The signature of a change in the structural relaxation of water from fragile to strong is also found by examining the behaviour of the excess entropy at decreasing temperature.

  12. The springs of Lake Pátzcuaro: chemistry, salt-balance, and implications for the water balance of the lake

    USGS Publications Warehouse

    Bischoff, James L.; Israde-Alcántara, Isabel; Garduno-Monroy, Victor H.; Shanks, Wayne C.

    2004-01-01

    Lake Pa??tzcuaro, the center of the ancient Tarascan civilization located in the Mexican altiplano west of the city of Morelia, has neither river input nor outflow. The relatively constant lake-salinity over the past centuries indicates the lake is in chemical steady state. Springs of the south shore constitute the primary visible input to the lake, so influx and discharge must be via sub-lacustrine ground water. The authors report on the chemistry and stable isotope composition of the springs, deeming them representative of ground-water input. The springs are dominated by Ca, Mg and Na, whereas the lake is dominated by Na. Combining these results with previously published precipitation/rainfall measurements on the lake, the authors calculate the chemical evolution from spring water to lake water, and also calculate a salt balance of the ground-water-lake system. Comparing Cl and ??18O compositions in the springs and lake water indicates that 75-80% of the spring water is lost evaporatively during evolution toward lake composition. During evaporation Ca and Mg are lost from the water by carbonate precipitation. Each liter of spring water discharging into the lake precipitates about 18.7 mg of CaCO3. Salt balance calculations indicate that ground water input to the lake is 85.9??106 m3/a and ground water discharge from the lake is 23.0??106 m3/a. Thus, the discharge is about 27% of the input, with the rest balanced by evaporation. A calculation of time to reach steady-state ab initio indicates that the Cl concentration of the present day lake would be reached in about 150 a. ?? 2004 Elsevier Ltd. All rights reserved.

  13. Sodium chloride crystallization from drying drops of albumin-salt solutions with different albumin concentrations

    NASA Astrophysics Data System (ADS)

    Yakhno, T. A.

    2015-11-01

    The salt nature of crystalline structures resulting from drying albumin-salt solutions with a low (<1 wt %) and high (7 and 9 wt %) concentration of albumin and a NaCl concentration kept at a physiological level (0.9 wt %) is experimentally substantiated. Such a conclusion is drawn from the dynamics of phase transitions, morphological studies, and differences between the physicochemical properties of albumin and salt. Obtained data give a deeper insight into the albumin and salt distributions in drying liquids.

  14. Geotechnical factors and guidelines for storage of compressed air in solution-mined salt cavities

    SciTech Connect

    Allen, R.D.; Doherty, T.J.; Thoms, R.L.

    1982-05-01

    The state of knowledge about utilization of solution-mined salt cavities for CAES including laboratory experiments, numerical modeling, field characterization, solution mining experience, and operating parameters is outlined in this report. Topics evaluated in recent studies include: cavern geometry and size; long-term creep and creep rupture of rock salt; effects of pressure and temperature loading rates; low frequency fatigue; progressive deterioration of salt fabric with possible air penetration; cavern monitoring methods; and salt properties at nonambient conditions. Currently, the only CAES operational facility in the world is located at Huntorf, West Germany. This CAES facility uses two solution-mined salt caverns for air storage and has been operating successfully for more than 2 years. Stability criteria for solution-mined salt caverns from the Huntorf facility and recent field and laboratory studies are included in this report.

  15. Novel Superdielectric Materials: Aqueous Salt Solution Saturated Fabric

    PubMed Central

    Phillips, Jonathan

    2016-01-01

    The dielectric constants of nylon fabrics saturated with aqueous NaCl solutions, Fabric-Superdielectric Materials (F-SDM), were measured to be >105 even at the shortest discharge times (>0.001 s) for which reliable data could be obtained using the constant current method, thus demonstrating the existence of a third class of SDM. Hence, the present results support the general theoretical SDM hypothesis, which is also supported by earlier experimental work with powder and anodized foil matrices: Any material composed of liquid containing dissolved, mobile ions, confined in an electrically insulating matrix, will have a very high dielectric constant. Five capacitors, each composed of a different number of layers of salt solution saturated nylon fabric, were studied, using a galvanostat operated in constant current mode. Capacitance, dielectric constant, energy density and power density as a function of discharge time, for discharge times from ~100 s to nearly 0.001 s were recorded. The roll-off rate of the first three parameters was found to be nearly identical for all five capacitors tested. The power density increased in all cases with decreasing discharge time, but again the observed frequency response was nearly identical for all five capacitors. Operational limitations found for F-SDM are the same as those for other aqueous solution SDM, particularly a low maximum operating voltage (~2.3 V), and dielectric “constants” that are a function of voltage, decreasing for voltages higher than ~0.8 V. Extrapolations of the present data set suggest F-SDM could be the key to inexpensive, high energy density (>75 J/cm3) capacitors. PMID:28774037

  16. Distribution coefficients of vitamin B2 in hydrophilic organic solvent-aqueous salt solution systems

    NASA Astrophysics Data System (ADS)

    Korenman, Ya. I.; Mokshina, N. Ya.; Zykov, A. V.

    2010-03-01

    Distribution coefficients of vitamin B2 in hydrophilic solvent ( n-butanol, isopropanol, acetone, ethyl acetate, and their mixtures)-aqueous salt (potassium chloride, sodium fluoride, and ammonium sulfate salting-out agents) solution systems were calculated. The synergic effect and optimum proportions of components in the solvent mixture for efficient extraction of vitamin B2 from aqueous solutions were established.

  17. Water and solute balances as a basis for sustainable irrigation agriculture

    NASA Astrophysics Data System (ADS)

    Pla-Sentís, Ildefonso

    2015-04-01

    The growing development of irrigated agriculture is necessary for the sustainable production of the food required by the increasing World's population. Such development is limited by the increasing scarcity and low quality of the available water resources and by the competitive use of the water for other purposes. There are also increasing problems of contamination of surface and ground waters to be used for other purposes by the drainage effluents of irrigated lands. Irrigation and drainage may cause drastic changes in the regime and balance of water and solutes (salts, sodium, contaminants) in the soil profile, resulting in problems of water supply to crops and problems of salinization, sodification and contamination of soils and ground waters. This is affected by climate, crops, soils, ground water depth, irrigation and groundwater composition, and by irrigation and drainage management. In order to predict and prevent such problems for a sustainable irrigated agriculture and increased efficiency in water use, under each particular set of conditions, there have to be considered both the hydrological, physical and chemical processes determining such water and solute balances in the soil profile. In this contribution there are proposed the new versions of two modeling approaches (SOMORE and SALSODIMAR) to predict those balances and to guide irrigation water use and management, integrating the different factors involved in such processes. Examples of their application under Mediterranean and tropical climate conditions are also presented.

  18. Density functional theories of surface interactions in salt solutions.

    PubMed

    Forsman, Jan

    2009-02-14

    Most current density functional theories rely upon the presence of hard cores, also between ions of like charge. These hard cores should in principle reflect exchange repulsion. However, by the way in which these theories are formulated, the hard cores effectively determine the range of ion-ion correlations. This is because the mutual repulsion between like-charged ions is truncated below the corresponding hard sphere diameter. In most relevant applications, at least those related to ion correlations and surface forces in colloidal dispersions, exchange repulsion between like-charged ions is unimportant. This can easily be demonstrated by simulations. Unfortunately, the hard cores can in practice serve as fitting parameters in calculations with traditional density functional theory. In this work, we present alternative density functional theories to describe aqueous salt solutions. In these approaches, an approximation of the relevant "Coulomb hole" that results from correlations between like-charged ions is calculated for the system under study. Hence, our theories are completely free from fitting parameters, and the results are appropriately insensitive to the exchange repulsion acting between ions of like charge. The theories are evaluated by comparing predictions with simulation data, with an emphasis on ion correlations and surface interactions.

  19. Salting-out effects in aqueous ionic liquid solutions: cloud-point temperature shifts.

    PubMed

    Trindade, Joana R; Visak, Zoran P; Blesic, Marijana; Marrucho, Isabel M; Coutinho, João A P; Lopes, José N Canongia; Rebelo, Luis P N

    2007-05-10

    The effects of the addition of three inorganic salts, namely, NaCl, Na(2)SO(4), and Na(3)PO(4), on the liquid-liquid (L-L) phase diagram of aqueous solutions containing the model ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate, [bmim][BF(4)], were investigated. All three inorganic salts trigger salting-out effects, leading to significant upward shifts of the L-L demixing temperatures of the systems. The magnitude of the shifts depends on both the water-structuring nature of the salt and its concentration; that is, the effects are correlated with the ionic strength of the solution and the Gibbs free energy of hydration of the inorganic salt. The pH effect and the occurrence of salt precipitation in concentrated solutions are also discussed.

  20. ISOPAR L Release Rates from Saltstone Using Simulated Salt Solutions

    SciTech Connect

    Bronikowski, M

    2006-02-06

    The Modular Caustic-Side Solvent Extraction (CSSX) Unit (MCU) and the Salt Waste Processing Facility (SWPF) will produce a Deactivated Salt Solution (DSS) that will go to the Saltstone Production Facility (SPF). Recent information indicates that solvent entrainment in the DSS is larger than expected. The main concern is with Isopar{reg_sign} L, the diluent in the solvent mixture, and its flammability in the saltstone vault. If it is assumed that all the Isopar{reg_sign} L is released instantaneously into the vault from the curing grout before each subsequent pour; the Isopar{reg_sign} L in the vault headspace is well mixed; and each pour displaces an equivalent volume of headspace, the allowable concentration of Isopar{reg_sign} L in the DSS sent to SPF has been calculated at approximately 4 ppm. The amount allowed would be higher, if the release from grout were significantly less. The Savannah River National Laboratory was tasked with determining the release of Isopar{reg_sign} L from saltstone prepared with a simulated DSS with Isopar{reg_sign} L concentrations ranging from 50 mg/L to 200 mg/L in the salt fraction and with test temperatures ranging from ambient to 95 C. The results from the curing of the saltstone showed that the Isopar{reg_sign} L release data can be treated as a percentage of initial concentration in the concentration range studied. The majority of the Isopar{reg_sign} L that was released over the test duration was released in the first few days. The release of Isopar{reg_sign} L begins immediately and the rate of release decreases over time. At higher temperatures the immediate release is larger than at lower temperatures. In one test at 95 C essentially all of the Isopar{reg_sign} L was released in three months. Initial curing temperature was found to be very important as slight variations during the first few days affected the final Isopar{reg_sign} L amount released. Short scoping tests at 95 C with solvent containing all components (Isopar

  1. ISOPAR L RELEASE RATES FROM SALTSTONE USING SIMULATED SALT SOLUTIONS

    SciTech Connect

    Zamecnik, J; Michael Bronikowski, M; Alex Cozzi, A; Russell Eibling, R; Charles Nash, C

    2008-07-31

    The Modular Caustic-Side Solvent Extraction (CSSX) Unit (MCU) and the Salt Waste Processing Facility (SWPF) will produce a Decontaminated Salt Solution (DSS) that will go to the Saltstone Production Facility (SPF). Recent information indicates that solvent entrainment in the DSS is larger than expected. The main concern is with Isopar{reg_sign} L, the diluent in the solvent mixture, and its flammability in the saltstone vault. If it is assumed that all the Isopar{reg_sign} L is released instantaneously into the vault from the curing grout before each subsequent pour, the Isopar{reg_sign} L in the vault headspace is well mixed, and each pour displaces an equivalent volume of headspace, the maximum concentration of Isopar{reg_sign} L in the DSS to assure 25% of the lower flammable limit is not exceeded has been determined to be about 4 ppm. The amount allowed would be higher if the release from grout were significantly less. The Savannah River National Laboratory was tasked with determining the release of Isopar{reg_sign} L from saltstone prepared with a simulated DSS with Isopar{reg_sign} L concentrations ranging from 50 to 200 mg/L in the salt fraction and with test temperatures ranging from ambient to 95 C. The results from the curing of the saltstone showed that the amount of Isopar{reg_sign} L released versus time can be treated as a percentage of initial amount present; there was no statistically significant dependence of the release rate on the initial concentration. The majority of the Isopar{reg_sign} L that was released over the test duration was released in the first few days. The release of Isopar{reg_sign} L begins immediately and the rate of release decreases over time. At higher temperatures the immediate release rate is larger than at lower temperatures. Initial curing temperature was found to be very important as slight variations during the first few hours or days had a significant effect on the amount of Isopar{reg_sign} L released. Short scoping

  2. Large time behavior of solutions for hyperbolic balance laws

    NASA Astrophysics Data System (ADS)

    Yu, Hongjun

    2016-11-01

    We study the existence and the large time behavior of global solutions to the initial value problem for hyperbolic balance laws in n space dimensions with n ≥ 3 admitting an entropy and satisfying the stable condition. We first construct global existence of the solutions to such a system around a steady state if the initial energy is small enough. Then we show that k-order derivatives of these solutions approach a constant state in the Lp-norm at a rate O (t -1/2 (k + ρ +n/2 - n/p)) with p ∈ [ 2 , ∞ ] and ρ ∈ [ 0 ,n/2 ] provided that initially ‖z0 ‖ B˙2, ∞ - ρ < ∞, where B˙2, ∞ - ρ is a homogeneous Besov space. These decay results do not impose an additional smallness assumption on Lp norm of the initial data and we thus improve the results in [3,19]. We also show faster decay results in the sense that if ‖ Pz0 ‖ B˙2, ∞ - ρ +‖ (I - P)z0 ‖ B˙2, ∞ - ρ + 1 < ∞ with ρ ∈ (n/2 ,n + 2/2 ], k-order derivatives of the solutions approach a constant state in the Lp-norm at a rate O (t -1/2 (k + ρ + 1 +n/2 - n/p )).

  3. A Study of Novel Hexavalent Phosphazene Salts as Draw Solutes in Forward Osmosis

    SciTech Connect

    Mark L. Stone; Aaron D. Wilson; Mason K. Harrup; Frederick F. Stewart

    2013-03-01

    Two novel multi-valent salts based on phosphazene chemistry have been synthesized and characterized as forward osmosis (FO) draw solutes. Commercially obtained hexachlorocyclotriphosphazene was reacted with the sodium salt of 4-ethylhydroxybenzoate to yield hexa(4-ethylcarboxylatophenoxy)phosphazene. Hydrolysis, followed by and neutralization with NaOH or LiOH, of the resulting acidic moieties yielded water soluble sodium and lithium phosphazene salts, respectively. Degrees of dissociation were determined through osmometry over the range of 0.05-0.5 m, giving degrees of 3.08-4.95 per mole, suggesting a high osmotic potential. The Li salt was found to be more ionized in solution than the sodium salt, and this was reflected in FO experiments where the Li salt gave higher initial fluxes (~ 7 L/m2h) as compared to the sodium salt (~6 L/m2h) at identical 0.07 m draw solution concentrations at 30 °C. Longer term experiments revealed no detectable degradation of the salts; however some hydrolysis of the cellulose acetate membrane was observed, presumably due to the pH of the phosphazene salt draw solution (pH = ~8).

  4. Concentration and precipitation of NaCl and KCl from salt cake leach solutions by electrodialysis

    SciTech Connect

    Sreenivasarao, K; Patsiogiannis, F.; Hryn, J.N.

    1997-02-09

    Electrodialysis was investigated for cost-effective recovery of salt from salt cake leach solutions. (Salt cake is a waste stream generated by the aluminum industry during treatment of aluminum drosses and scrap.) We used a pilot-scale electrodialysis stack of 5 membrane pairs, each with an effective area of 0.02 m{sup 2}. The diluate stream contained synthetic NaCl, KCl,mixtures of NaCl and KCl, and actual salt cake leach solutions (mainly NaCl and KCl, with small amounts of MgCl{sub 2}). We concentrated and precipitated NaCl and KCl salts from the concentrate steam when the initial diluate stream concentration was 21.5 to 28.8 wt% NaCl and KCl. We found that water transferring through the membranes was a significant factor in overall efficiency of salt recovery by electrodialysis.

  5. Salt weathering in Egyptian limestone after laboratory simulations with continuous flow of salt solutions at different temperatures

    NASA Astrophysics Data System (ADS)

    Aly, Nevin; Gomez-Heras, Miguel; Hamed, Ayman; Alvarez de Buergo, Monica

    2013-04-01

    weathering in Egyptian limestone after laboratory simulations with continuous flow of salt solutions at different temperatures Nevin Aly Mohamed (1), Miguel Gomez - Heras(2), Ayman Hamed Ahmed (1), and Monica Alvarez de Buergo(2). (1) Faculty of Pet. & Min. Engineering- Suez Canal University, Suez, Egypt, (2) Instituto de Geociencias (CSIC-UCM) Madrid. Spain. Limestone is one of the most frequent building stones in Egypt and is used since the time of ancient Egyptians and salt weathering is one of the main threats to its conservation. Most of the limestone used in historical monuments in Cairo is a biomicrite extracted from the Mid-Eocene Mokattam Group. During this work, cylindrical samples (2.4 cm diameter and approx. 4.8 cm length) were subjected, in a purpose-made simulation chamber, to simulated laboratory weathering tests with fixed salt concentration (10% weight NaCl solution), at different temperatures, which were kept constant throughout each test (10, 20, 30, 40 oC). During each test, salt solutions flowed continuously imbibing samples by capilarity. Humidity within the simulation chamber was reduced using silica gel to keep it low and constant to increase evaporation rate. Temperature, humidity inside the simulation chamber and samples weight were digitally monitored during each test. Results show the advantages of the proposed experimental methodology using a continuous flow of salt solutions and shed light on the effect of temperature on the dynamics of salt crystallization on and within samples. Research funded by mission sector of high education ministry, Egypt and Geomateriales S2009/MAT-1629.

  6. Testing of stripping columns for the removal of benzene from aqueous radioactive salt solution

    SciTech Connect

    Georgeton, G.K.; Taylor, G.A.; Gaughan, T.P.

    1995-06-27

    Radioactive high level wastes (HLW) generated from production of special nuclear materials at the Savannah River Site (SRS) are held in interim storage in 51 underground, million gallon tanks. Radioactive cesium ({sup 137}Cs) is segregated by evaporation of aqueous waste solution for interim storage in a salt matrix comprised of Na and K salts or in concentrated salt solution. The saltcake will be dissolved and {sup 137}Cs will be separated from the nonradioactive salts in solution in the In-Tank Precipitation (ITP) Process. The cesium will be combined with other radioactive species and glass formers to be melted and poured into stainless steel canisters in the Defense Waste Processing Facility (DWPF). The salt solution remaining after decontamination in the ITP process will be incorporated into grout for disposal at the site`s Saltstone facility. In the ITP facility, sodium tetraphenylborate (STPB) will be added to precipitate the cesium. Potassium in the waste solution also reacts with STPB and precipitates. Due to radiolytic and chemical degradation of the tetraphenylborate (TPB) precipitate, benzene is generated. The benzene dissolves into the decontaminated salt solution (DSS) and into water (WW) used to {open_quotes}wash{close_quotes} the precipitate to lower the soluble salt content of the slurry. Safety and processing requirements for disposal of the DSS and for temporary storage of the WW dictate that the benzene concentration be reduced.

  7. Conformations of gelatin in trivalent chromium salt solutions: Viscosity and dynamic light scattering study

    NASA Astrophysics Data System (ADS)

    Qiao, Congde; Zhang, Jianlong; Kong, Aiqun

    2017-02-01

    An investigation of the influences of pH, salt type, and salt concentration on the conformations of gelatin molecules in trivalent chromium salt solutions was performed by viscosity and dynamic light scattering (DLS) techniques. It was found that the viscosity behaviors as polyelectrolytes or polyampholytes depended on the charge distribution on the gelatin chains, which can be tuned by the value of pH of the gelatin solution. The intrinsic viscosity of gelatin in basic chromium sulfate aqueous solution at pH = 2.0 first decreased and then increased with increasing Cr(OH)SO4 concentration, while a monotonic decrease of the intrinsic viscosity of gelatin was observed in CrCl3 solution. However, the intrinsic viscosity of gelatin at pH = 5.0 was found to be increased first and then decreased with an increase in salt concentration in Cr(OH)SO4 solution, as well as in CrCl3 solution. We suggested that the observed viscosity behavior of gelatin in trivalent chromium salt solutions was attributed to the comprehensive effects of shielding, overcharging, and crosslinking (complexation) caused by the introduction of the different counterions. In addition, the average hydrodynamic radius ( R h ) of gelatin molecules in various salt solutions was determined by DLS. It was found that the change trend of R h with salt concentration was the same as the change of intrinsic viscosity. Based on the results of the viscosity and DLS, a possible mechanism for the conformational transition of gelatin chains with external conditions including pH, salt concentration, and salt type is proposed.

  8. Salt balance: From space experiments to revolutionizing new clinical concepts on earth - A historical review

    NASA Astrophysics Data System (ADS)

    Gerzer, Rupert

    2014-11-01

    For a long time, sodium balance appeared to be a “done deal” and was thought to be well understood. However, experiments in preparation of space missions showed that the concept of osmotic sodium storage and close correlations of sodium with water balance are only part of the regulatory mechanisms of body salt. By now it has turned out that the human skin is an important storage place and regulator for sodium, that sodium storage involves macrophages which in turn salt-dependently co-regulate blood pressure, that body sodium also strongly influences bone and protein metabolism, and that immune functions are also strongly influenced by sodium. In addition, the aging process appears to lead to increased body sodium storage, which in turn might influence the aging process of the human body. The current review article summarizes the developments that have led to these revolutionizing new findings and concepts as well as consequences deriving from these findings. Therefore, it is not intended in this article to give a complete literature overview over the whole field but to focus on such key literature and considerations that led to the respective developments.

  9. Novel, electrolyte solutions comprising fully inorganic salts with high anodic stability for rechargeable magnesium batteries.

    PubMed

    Doe, Robert E; Han, Ruoban; Hwang, Jaehee; Gmitter, Andrew J; Shterenberg, Ivgeni; Yoo, Hyun Deog; Pour, Nir; Aurbach, Doron

    2014-01-07

    Herein the first inorganic magnesium salt solution capable of highly reversible magnesium electrodeposition is presented. Synthesized by acid-base reaction of MgCl2 and Lewis acidic compounds such as AlCl3, this salt class demonstrates upwards of 99% Coulombic efficiency, deposition overpotential of <200 mV, and anodic stability of 3.1 V.

  10. Novel, electrolyte solutions comprising fully inorganic salts with high anodic stability for rechargeable magnesium batteries

    SciTech Connect

    Doe, RE; Han, R; Hwang, J; Gmitter, AJ; Shterenberg, I; Yoo, HD; Pour, N; Aurbach, D

    2014-01-01

    Herein the first inorganic magnesium salt solution capable of highly reversible magnesium electrodeposition is presented. Synthesized by acid-base reaction of MgCl2 and Lewis acidic compounds such as AlCl3, this salt class demonstrates upwards of 99% Coulombic efficiency, deposition overpotential of <200 mV, and anodic stability of 3.1 V.

  11. Body salt and water balances in cardiothoracic surgery patients with intensive care unit-acquired hyponatremia.

    PubMed

    Stieglmair, Sandra; Lindner, Gregor; Lassnigg, Andrea; Mouhieddine, Mohamed; Hiesmayr, Michael; Schwarz, Christoph

    2013-12-01

    Hyponatremia is frequently observed in intensive care unit (ICU) patients, but there is still lack information on the physiological mechanisms of development. In this retrospective analysis we performed tonicity balances in 54 patients with ICU acquired hyponatremia. We calculated fluid and solute in and outputs during 24 hours in 106 patient days with decreasing serum-sodium levels. We could observe a positive fluid balance as a single reason for hyponatremia in 25% of patients and a negative solute balance in 57%. In 18% both factors contributed to the decrease in serum-sodium. Hyponatremic patients had renal water retention, measured by electrolyte free water clearance calculation in 79% and positive input of free water in 67% as reasons for decline of serum-sodium. The theoretical change of serum sodium during 24 hours according to the calculations of measured balances correlated well with the real change of serum sodium (r = 0.78, P < .01). Balance studies showed that renal water retention together with renal sodium loss and high electrolyte free water input are the major contributors to the development of hyponatremia. Control of renal water and sodium handling by urine analysis may contribute to a better fluid management in the ICU population. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Modeling of Flow, Transport and Controlled Sedimentation Phenomena during Mixing of Salt Solutions in Complex Porous Formations

    NASA Astrophysics Data System (ADS)

    Skouras, Eugene D.; Jaho, Sofia; Pavlakou, Efstathia I.; Sygouni, Varvara; Petsi, Anastasia; Paraskeva, Christakis A.

    2015-04-01

    The deposition of salts in porous media is a major engineering phenomenon encountered in a plethora of industrial and environmental applications where in some cases is desirable and in other not (oil production, geothermal systems, soil stabilization etc). Systematic approach of these problems requires knowledge of the key mechanisms of precipitating salts within the porous structures, in order to develop new methods to control the process. In this work, the development and the solution of spatiotemporally variable mass balances during salt solution mixing along specific pores were performed. Both analytical models and finite differences CFD models were applied for the study of flow and transport with simultaneous homogeneous and heterogeneous nucleation (by crystal growth on the surface of the pores) in simple geometries, while unstructured finite elements and meshless methods were developed and implemented for spatial discretization, reconstruction, and solution of transport equations and homogeneous / heterogeneous reactions in more complex geometries. At initial stages of this work, critical problem parameters were identified, such as the characteristics of the porosity, the number of dissolved components, etc. The parameters were then used for solving problems which correspond to available experimental data. For each combination of ions and materials, specific data and process characteristics were included: (a) crystal kinetics (nucleation, growth rates or reaction surface rates of crystals, critical suspension concentrations), (b) physico-chemical properties (bulk density, dimensions of generated crystals, ion diffusion coefficients in the solution), (c) operating parameters (macroscopic velocity, flow, or pressure gradient of the solution, ion concentration) (d) microfluidic data (geometry, flow area), (e) porosity data in Darcy description (initial porosity, specific surface area, tortuosity). During the modeling of flow and transport in three

  13. Location of microseismic swarms induced by salt solution mining

    NASA Astrophysics Data System (ADS)

    Kinscher, J.; Bernard, P.; Contrucci, I.; Mangeney, A.; Piguet, J. P.; Bigarre, P.

    2015-01-01

    Ground failures, caving processes and collapses of large natural or man-made underground cavities can produce significant socio-economic damages and represent a serious risk envisaged by the mine managements and municipalities. In order to improve our understanding of the mechanisms governing such a geohazard and to test the potential of geophysical methods to prevent them, the development and collapse of a salt solution mining cavity was monitored in the Lorraine basin in northeastern France. During the experiment, a huge microseismic data set (˜50 000 event files) was recorded by a local microseismic network. 80 per cent of the data comprised unusual swarming sequences with complex clusters of superimposed microseismic events which could not be processed through standard automatic detection and location routines. Here, we present two probabilistic methods which provide a powerful tool to assess the spatio-temporal characteristics of these swarming sequences in an automatic manner. Both methods take advantage of strong attenuation effects and significantly polarized P-wave energies at higher frequencies (>100 Hz). The first location approach uses simple signal amplitude estimates for different frequency bands, and an attenuation model to constrain the hypocentre locations. The second approach was designed to identify significantly polarized P-wave energies and the associated polarization angles which provide very valuable information on the hypocentre location. Both methods are applied to a microseismic data set recorded during an important step of the development of the cavity, that is, before its collapse. From our results, systematic spatio-temporal epicentre migration trends are observed in the order of seconds to minutes and several tens of meters which are partially associated with cyclic behaviours. In addition, from spatio-temporal distribution of epicentre clusters we observed similar epicentre migration in the order of hours and days. All together, we

  14. Students' Misconceptions in Electrochemistry: Current Flow in Electrolyte Solutions and the Salt Bridge.

    ERIC Educational Resources Information Center

    Sanger, Michael J.; Greenbowe, Thomas J.

    1997-01-01

    Examines students' misconceptions and proposed mechanisms related to current flow in electrolyte solutions and the salt bridge. Confirms reported misconceptions and identifies several new ones. Discusses probable sources of misconceptions and some methods for preventing them. Contains 27 references. (JRH)

  15. Materials and methods for stabilizing nanoparticles in salt solutions

    DOEpatents

    Robinson, David Bruce; Zuckermann, Ronald; Buffleben, George M.

    2013-06-11

    Sequence-specific polymers are proving to be a powerful approach to assembly and manipulation of matter on the nanometer scale. Ligands that are peptoids, or sequence-specific N-functional glycine oligomers, allow precise and flexible control over the arrangement of binding groups, steric spacers, charge, and other functionality. We have synthesized short peptoids that can prevent the aggregation of gold nanoparticles in high-salt environments including divalent salt, and allow co-adsorption of a single DNA molecule. This degree of precision and versatility is likely to prove essential in bottom-up assembly of nanostructures and in biomedical applications of nanomaterials.

  16. Effect of Salt Concentration on the Structure of Poly(Vinyl Alcohol) Cryogels Obtained from Aqueous Salt Solutions

    NASA Astrophysics Data System (ADS)

    Tretinnikov, O. N.; Sushko, N. I.; Zagorskaya, S. A.

    2015-03-01

    The degree of polymer crystallinity and water content on the surfaces and in the bulk of poly(vinyl alcohol) (PVA) cryogels prepared from aqueous salt solutions were determined as functions of KCl concentration using FTIR-ATR spectroscopy. It was found that the degree of PVA crystallinity increased with increasing KCl concentration and was much greater in the cryogel bulk than on its surfaces. Addition of salt at a concentration of 1.3 M increased the degree of polymer crystallinity on the cryogel surfaces by 1.6-2.3 times whereas the crystallinity in the bulk increased by 3.3-4 times. The cryogel water contents on the surfaces and in the bulk were approximately equal and were practically independent of the salt concentration.

  17. Salt-Finger Convection in a Stratified Fluid Layer Induced by Thermal and Solutal Capillary Motion

    NASA Technical Reports Server (NTRS)

    Chen, Chuan F.; Chan, Cho Lik

    1996-01-01

    Salt-finger convection in a double-diffusive system is a motion driven by the release of gravitational potential due to different diffusion rates. Normally, when the gravitational field is reduced, salt-finger convection together with other convective motions driven by buoyancy forces will be rapidly suppressed. However, because the destabilizing effect of the concentration gradient is amplified by the Lewis number, with values varying from 10(exp 2) for aqueous salt solutions to 10 (exp 4) for liquid metals, salt-finger convection may be generated at much reduced gravity levels. In the microgravity environment, the surface tension gradient assumes a dominant role in causing fluid motion. In this paper, we report on some experimental results showing the generation of salt-finger convection due to capillary motio on the surface of a stratified fluid layer. A numerical simulation is presented to show the cause of salt-finger convection.

  18. Pesticide Removal from Aqueous Solutions by Adding Salting Out Agents

    PubMed Central

    Moscoso, Fátima; Deive, Francisco J.; Esperança, José M. S. S.; Rodríguez, Ana

    2013-01-01

    Phase segregation in aqueous biphasic systems (ABS) composed of four hydrophilic ionic liquids (ILs): 1-butyl-3-methylimidazolium methylsulfate and 1-ethyl-3-methylimidazolium methylsulfate (CnC1im C1SO4, n = 2 and 4), tributylmethyl phosphonium methylsulfate (P4441 C1SO4) and methylpyridinium methylsulfate (C1Py C1SO4) and two high charge density potassium inorganic salts (K2CO3 and K2HPO4) were determined by the cloud point method at 298.15 K. The influence of the addition of the selected inorganic salts to aqueous mixtures of ILs was discussed in the light of the Hofmeister series and in terms of molar Gibbs free energy of hydration. The effect of the alkyl chain length of the cation on the methylsulfate-based ILs has been investigated. All the solubility data were satisfactorily correlated to several empirical equations. A pesticide (pentachlorophenol, PCP) extraction process based on the inorganic salt providing a greater salting out effect was tackled. The viability of the proposed process was analyzed in terms of partition coefficients and extraction efficiencies. PMID:24145747

  19. IR spectroscopy of aqueous alkali halide solutions: Pure salt-solvated water spectra and hydration numbers

    NASA Astrophysics Data System (ADS)

    Max, Jean-Joseph; Chapados, Camille

    2001-08-01

    Extrapolation techniques were used to obtain pure salt-solvated water spectra from the attenuated total reflection infrared spectra (ATR-IR) of aqueous solutions of the nine alkali halide salts LiCl, NaCl, KCl, CsCl, NaBr, KBr, NaI, KI, and CsI and the alkaline-earth chloride salt MgCl2. These salts ionize completely in water. The ions by themselves do not absorb in the IR, but their interactions with water can be observed and analyzed. A pure salt-solvated water spectrum is easier to analyze than that of a combined solution of pure water and salt-solvated water. Although the salt-solvated water spectra examined have distinctive signatures, they can be classified in three categories: those similar to NaCl; those not similar to NaCl; and MgCl2, in a class by itself. Each of the pure salt-solvated water spectra differs from that of liquid water, though the number of bands is the same. From the Gaussian band fitting, we found that the positions of the bands were fairly constant, whereas their intensities differed. The salt hydration numbers were determined: for NaCl, KCl, NaBr, KBr, and CsI solutions it is 5; for KI and MgCL2 it is 4; for NaI it is 3.5; for CsCl it is 3; and for LiCl it is 2. From these results we found that each pair of ions (monoatomic ions) of the ten salt solutions studied are close bound and form a complex in a cluster organization with a fixed number of water molecules.

  20. Balanced Crystalloids versus Saline in the Intensive Care Unit. The SALT Randomized Trial.

    PubMed

    Semler, Matthew W; Wanderer, Jonathan P; Ehrenfeld, Jesse M; Stollings, Joanna L; Self, Wesley H; Siew, Edward D; Wang, Li; Byrne, Daniel W; Shaw, Andrew D; Bernard, Gordon R; Rice, Todd W

    2017-05-15

    Saline is the intravenous fluid most commonly administered to critically ill adults, but it may be associated with acute kidney injury and death. Whether use of balanced crystalloids rather than saline affects patient outcomes remains unknown. To pilot a cluster-randomized, multiple-crossover trial using software tools within the electronic health record to compare saline to balanced crystalloids. This was a cluster-randomized, multiple-crossover trial among 974 adults admitted to a tertiary medical intensive care unit from February 3, 2015 to May 31, 2015. The intravenous crystalloid used in the unit alternated monthly between saline (0.9% sodium chloride) and balanced crystalloids (lactated Ringer's solution or Plasma-Lyte A). Enrollment, fluid delivery, and data collection were performed using software tools within the electronic health record. The primary outcome was the difference between study groups in the proportion of isotonic crystalloid administered that was saline. The secondary outcome was major adverse kidney events within 30 days (MAKE30), a composite of death, dialysis, or persistent renal dysfunction. Patients assigned to saline (n = 454) and balanced crystalloids (n = 520) were similar at baseline and received similar volumes of crystalloid by 30 days (median [interquartile range]: 1,424 ml [500-3,377] vs. 1,617 ml [500-3,628]; P = 0.40). Saline made up a larger proportion of the isotonic crystalloid given in the saline group than in the balanced crystalloid group (91% vs. 21%; P < 0.001). MAKE30 did not differ between groups (24.7% vs. 24.6%; P = 0.98). An electronic health record-embedded, cluster-randomized, multiple-crossover trial comparing saline with balanced crystalloids can produce well-balanced study groups and separation in crystalloid receipt. Clinical trial registered with www.clinicaltrials.gov (NCT 02345486).

  1. Specific Ion Effects: Why the Properties of Lysozyme in Salt Solutions Follow a Hofmeister Series

    PubMed Central

    Boström, M.; Williams, D. R. M.; Ninham, B. W.

    2003-01-01

    Protein solubility in aqueous solutions depends in a complicated and not well understood way on pH, salt type, and salt concentration. Why for instance does the use of two different monovalent salts, potassium thiocyanate and potassium chloride, produce such different results? One important and previously neglected source of ion specificity is the ionic dispersion potential that acts between each ion and the protein. This attractive potential is found to be much stronger for SCN− than it is for Cl−. We present model calculations, performed within a modified ion-specific double-layer theory, that demonstrate the large effect of including these ionic dispersion potentials. The results are consistent with experiments performed on hen egg-white lysozymes and on neutral black lipid membranes. The calculated surface pH and net lysozyme charge depend strongly on the choice of anion. We demonstrate that the lysozyme net charge is larger, and the corresponding Debye length shorter, in a thiocyanate salt solution than in a chloride salt solution. Recent experiments have suggested that pKa values of histidines depend on salt concentration and on ionic species. We finally demonstrate that once ionic dispersion potentials are included in the theory these results can quantitatively be reinterpreted in terms of a highly specific surface pH (and a salt-independent pKa). PMID:12885620

  2. Correlation of second virial coefficient with solubility for proteins in salt solutions.

    PubMed

    Mehta, Chirag M; White, Edward T; Litster, James D

    2012-01-01

    In this work, osmotic second virial coefficients (B(22)) were determined and correlated with the measured solubilities for the proteins, α-amylase, ovalbumin, and lysozyme. The B(22) values and solubilities were determined in similar solution conditions using two salts, sodium chloride and ammonium sulfate in an acidic pH range. An overall decrease in the solubility of the proteins (salting out) was observed at high concentrations of ammonium sulfate and sodium chloride solutions. However, for α-amylase, salting-in behavior was also observed in low concentration sodium chloride solutions. In ammonium sulfate solutions, the B(22) are small and close to zero below 2.4 M. As the ammonium sulfate concentrations were further increased, B(22) values decreased for all systems studied. The effect of sodium chloride on B(22) varies with concentration, solution pH, and the type of protein studied. Theoretical models show a reasonable fit to the experimental derived data of B(22) and solubility. B(22) is also directly proportional to the logarithm of the solubility values for individual proteins in salt solutions, so the log-linear empirical models developed in this work can also be used to rapidly predict solubility and B(22) values for given protein-salt systems. Copyright © 2011 American Institute of Chemical Engineers (AIChE).

  3. Ion aggregation in high salt solutions: ion network versus ion cluster.

    PubMed

    Kim, Seongheun; Kim, Heejae; Choi, Jun-Ho; Cho, Minhaeng

    2014-09-28

    The critical aggregation phenomena are ubiquitous in many self-assembling systems. Ions in high salt solutions could also spontaneously form larger ion aggregates, but their effects on hydrogen-bond structures in water have long been controversial. Here, carrying out molecular dynamics (MD) simulation studies of high salt solutions and comparing the MD simulation results with infrared absorption and pump-probe spectroscopy of O-D stretch mode of HDO in highly concentrated salt solutions and (13)C-NMR chemical shift of S(13)CN(-) in KSCN solutions, we find evidence on the onset of ion aggregate and large-scale ion-ion network formation that concomitantly breaks water hydrogen-bond structure in certain salt solutions. Despite that these experimental results cannot provide direct evidence on the three-dimensional morphological structures of ion aggregates, they serve as reference data for verifying MD simulation methods. The MD results suggest that disrupted water hydrogen-bond network is intricately intertwined with ion-ion network. This further shows morphological variation of ion aggregate structures from ion cluster to ion network in high salt solutions that are interrelated to the onset of macroscopic aggregate formation and the water hydrogen-bond structure making and breaking processes induced by Hofmeister ions.

  4. Ion aggregation in high salt solutions: Ion network versus ion cluster

    SciTech Connect

    Kim, Seongheun; Kim, Heejae; Choi, Jun-Ho; Cho, Minhaeng

    2014-09-28

    The critical aggregation phenomena are ubiquitous in many self-assembling systems. Ions in high salt solutions could also spontaneously form larger ion aggregates, but their effects on hydrogen-bond structures in water have long been controversial. Here, carrying out molecular dynamics (MD) simulation studies of high salt solutions and comparing the MD simulation results with infrared absorption and pump-probe spectroscopy of O–D stretch mode of HDO in highly concentrated salt solutions and {sup 13}C-NMR chemical shift of S{sup 13}CN{sup −} in KSCN solutions, we find evidence on the onset of ion aggregate and large-scale ion-ion network formation that concomitantly breaks water hydrogen-bond structure in certain salt solutions. Despite that these experimental results cannot provide direct evidence on the three-dimensional morphological structures of ion aggregates, they serve as reference data for verifying MD simulation methods. The MD results suggest that disrupted water hydrogen-bond network is intricately intertwined with ion-ion network. This further shows morphological variation of ion aggregate structures from ion cluster to ion network in high salt solutions that are interrelated to the onset of macroscopic aggregate formation and the water hydrogen-bond structure making and breaking processes induced by Hofmeister ions.

  5. Water and solute mass balance of five small, relatively undisturbed watersheds in the U.S.

    USGS Publications Warehouse

    Peters, N.E.; Shanley, J.B.; Aulenbach, Brent T.; Webb, R.M.; Campbell, D.H.; Hunt, R.; Larsen, M.C.; Stallard, R.F.; Troester, J.; Walker, J.F.

    2006-01-01

    Geochemical mass balances were computed for water years 1992-1997 (October 1991 through September 1997) for the five watersheds of the U.S. Geological Survey Water, Energy, and Biogeochemical Budgets (WEBB) Program to determine the primary regional controls on yields of the major dissolved inorganic solutes. The sites, which vary markedly with respect to climate, geology, physiography, and ecology, are: Allequash Creek, Wisconsin (low-relief, humid continental forest); Andrews Creek, Colorado (cold alpine, taiga/tundra, and subalpine boreal forest); Ri??o Icacos, Puerto Rico (lower montane, wet tropical forest); Panola Mountain, Georgia (humid subtropical piedmont forest); and Sleepers River, Vermont (humid northern hardwood forest). Streamwater output fluxes were determined by constructing empirical multivariate concentration models including discharge and seasonal components. Input fluxes were computed from weekly wet-only or bulk precipitation sampling. Despite uncertainties in input fluxes arising from poorly defined elevation gradients, lack of dry-deposition and occult-deposition measurements, and uncertain sea-salt contributions, the following was concluded: (1) for solutes derived primarily from rock weathering (Ca, Mg, Na, K, and H4SiO4), net fluxes (outputs in streamflow minus inputs in deposition) varied by two orders of magnitude, which is attributed to a large gradient in rock weathering rates controlled by climate and geologic parent material; (2) the net flux of atmospherically derived solutes (NH4, NO3, SO4, and Cl) was similar among sites, with SO4 being the most variable and NH4 and NO3 generally retained (except for NO 3 at Andrews); and (3) relations among monthly solute fluxes and differences among solute concentration model parameters yielded additional insights into comparative biogeochemical processes at the sites. ?? 2005 Elsevier B.V. All rights reserved.

  6. Hydraulic conductivity of compacted clay liners permeated with inorganic salt solutions.

    PubMed

    Yilmaz, Gonca; Yetimoglu, Temel; Arasan, Seracettin

    2008-10-01

    Due to their low permeability, geosynthetic clay liners (GCLs) and compacted clay liners (CCLs) are the main materials used in waste disposal landfills. The hydraulic conductivity of GCLs and CCLs is closely related to the chemistry of the permeant fluid. In this study, the effect on the hydraulic conductivity of clays of five different inorganic salt solutions as permeant fluid was experimentally investigated. For this purpose, NaCl, NH(4)Cl, KCl, CaCl(2), and FeCl( 3) inorganic salt solutions were used at concentrations of 0.01, 0.10, 0.25, 0.50, 0.75 and 1 M. Laboratory hydraulic conductivity tests were conducted on low plasticity (CL) and high plasticity (CH) compacted raw clays. The change in electrical conductivity and pH values of the clay samples with inorganic salt solutions were also determined. The experimental test results indicated that the effect of inorganic salt solutions on CL clay was different from that on CH clay. The hydraulic conductivity was found to increase for CH clay when the salt concentrations increased whereas when the salt concentrations were increased, the hydraulic conductivity decreased for the CL clay.

  7. Analysis of Frozen Sulfate and Chloride Salt Solutions Using Laser-induced Breakdown Spectroscopy Under Martian Conditions

    NASA Astrophysics Data System (ADS)

    Schröder, S.; Pavlov, S. G.; Hübers, H.-W.; Rauschenbach, I.; Jessberger, E. K.

    2010-03-01

    We showed the feasibility of laser-induced breakdown spectroscopy to analyze different frozen salt solutions under martian conditions. We focused on chloride and sulphate salts which were found on Mars and could lower the freezing point of water.

  8. Influence of adding salt on ultrasonic atomization in an ethanol-water solution.

    PubMed

    Hamai, Koumei; Takenaka, Norimichi; Nanzai, Ben; Okitsu, Kenji; Bandow, Hiroshi; Maeda, Yasuaki

    2009-01-01

    Ethanol was enriched by ultrasonic atomization. Enrichment ratios were increased by adding salt to the ethanol solution. Different enrichment ratios were observed for different types of salts in a range of low ethanol concentrations. The enrichment ratio was significantly improved by adding K(2)CO(3) or (NH(4))(2)SO(4). It is concluded that this is due to enhanced interfacial adsorption of the ethanol. Addition of Na(2)CO(3) to the ethanol solution also enhanced the interfacial adsorption of the ethanol, but the effect was relatively small. Addition of NaCl to the ethanol solution did not enhance the interfacial adsorption of the ethanol.

  9. Length Scale Dependence of the Dynamic Properties of Hyaluronic Acid Solutions in the Presence of Salt

    SciTech Connect

    Horkay, Ferenc; Falus, Peter; Hecht, Anne-Marie; Geissler, Erik

    2010-12-07

    In solutions of the charged semirigid biopolymer hyaluronic acid in salt-free conditions, the diffusion coefficient D{sub NSE} measured at high transfer momentum q by neutron spin echo is more than an order of magnitude smaller than that determined by dynamic light scattering, D{sub DLS}. This behavior contrasts with neutral polymer solutions. With increasing salt content, D{sub DLS} approaches D{sub NSE}, which is independent of ionic strength. Contrary to theoretical expectation, the ion-polymer coupling, which dominates the low q dynamics of polyelectrolyte solutions, already breaks down at distance scales greater than the Debye-Hueckel length.

  10. Lanthanide salts solutions: representation of osmotic coefficients within the binding mean spherical approximation.

    PubMed

    Ruas, Alexandre; Moisy, Philippe; Simonin, Jean-Pierre; Bernard, Olivier; Dufrêche, Jean-François; Turq, Pierre

    2005-03-24

    Osmotic coefficients of aqueous solutions of lanthanide salts are described using the binding mean spherical approximation (BIMSA) model based on the Wertheim formalism for association. The lanthanide(III) cation and the co-ion are allowed to form a 1-1 ion pair. Hydration is taken into account by introducing concentration-dependent cation size and solution permittivity. An expression for the osmotic coefficient, derived within the BIMSA, is used to fit data for a wide variety of lanthanide pure salt aqueous solutions at 25 degrees C. A total of 38 lanthanide salts have been treated, including perchlorates, nitrates, and chlorides. For most solutions, good fits could be obtained up to high ionic strengths. The relevance of the fitted parameters has been discussed, and a comparison with literature values has been made (especially the association constants) when available.

  11. Soaking turkey meat in salt-glucose syrup solutions--an experimental study of mass transfers.

    PubMed

    Deumier, F; Collignan, A; Bohuon, P

    2002-08-01

    Turkey meat can be salted and dried in one step by soaking in a concentrated salt-glucose syrup solution at low temperature. Sugar impregnation is minimal; only low molecular weight sugars generally penetrate the product. Glucose uptake is very quick, suggesting the possible involvement of passive glucose transporters. The operational scope of this process, depending on the targeted end-product features, was determined for turkey meat on the basis of clearly characterized mass transport phenomena between the product and the soaking solution. With 2 cm thick meat fillets processed at 10 C it is thus possible to obtain salted-dried end-products containing 2 to 10% salt and 35 to 70% water, ranges that are compatible with a broad range of commercial cured products.

  12. Meat batter production in an extended vane pump-grinder injecting curing salt solutions to reduce energy requirements: variation of curing salt amount injected with the solution.

    PubMed

    Irmscher, Stefan B; Terjung, Eva-Maria; Gibis, Monika; Herrmann, Kurt; Kohlus, Reinhard; Weiss, Jochen

    2017-01-01

    The integration of a nozzle in an extended vane pump-grinder system may enable the continuous injection of curing salt solutions during meat batter production. The purpose of this work was to examine the influence of the curing salt amount injected with the solution (0-100%) on protein solubilisation, water-binding, structure, colour and texture of emulsion-type sausages. The amount of myofibrillar protein solubilised during homogenisation varied slightly from 33 to 36 g kg(-1) . Reddening was not noticeably impacted by the later addition of nitrite. L(*) ranged from 66.9 ± 0.3 to 67.8 ± 0.3, a(*) from 10.9 ± 0.1 to 11.2 ± 0.1 and b(*) from 7.7 ± 0.1 to 8.0 ± 0.1. Although softer sausages were produced when only water was injected, firmness increased with increasing curing salt amount injected and was similar to the control when the full amount of salt was used. The substitution of two-thirds of ice with a liquid brine may enable energy savings due to reduced power consumptions of the extended vane pump-grinder system by up to 23%. The injection of curing salt solutions is feasible without affecting structure and colour negatively. This constitutes a first step towards of an 'ice-free' meat batter production allowing for substantial energy savings due to lower comminution work. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  13. Conformational stability of alternating d (CG) oligomers in high salt solution.

    PubMed Central

    Quadrifoglio, F; Manzini, G; Vasser, M; Dinkelspiel, K; Crea, R

    1981-01-01

    The conformation of d (CG)n oligomers with n = 2,3 has been studied in aqueous solution in the presence of high salt concentration. A minimum n value of three is necessary to obtain a left-handed Z-helix. When d (CG)3 is flanked by three non Z-helicogenic alternating AT sequences the left-handed helix is unstable and a B-type conformation is obtained also at high salt concentration. PMID:6272229

  14. Fluid-loading solutions and plasma volume: Astro-ade and salt tablets with water

    NASA Technical Reports Server (NTRS)

    Fortney, Suzanne M.; Seinmann, Laura; Young, Joan A.; Hoskin, Cherylynn N.; Barrows, Linda H.

    1994-01-01

    Fluid loading with salt and water is a countermeasure used after space flight to restore body fluids. However, gastrointestinal side effects have been frequently reported in persons taking similar quantities of salt and water in ground-based studies. The effectiveness of the Shuttle fluid-loading countermeasure (8 gms salt, 0.97 liters of water) was compared to Astro-ade (an isotonic electrolyte solution), to maintain plasma volume (PV) during 4.5 hrs of resting fluid restriction. Three groups of healthy men (n=6) were studied: a Control Group (no drinking), an Astro-ade Group, and a Salt Tablet Group. Changes in PV after drinking were calculated from hematocrit and hemoglobin values. Both the Salt Tablet and Astro-ade Groups maintained PV at 2-3 hours after ingestion compared to the Control Group, which had a 6 percent decline. Side effects (thirst, stomach cramping, and diarrhea) were noted in at least one subject in both the Astro-ade and Salt Tablet Groups. Nausea and vomiting were reported in one subject in the Salt Tablet Group. It was concluded that Astro-ade may be offered as an alternate fluid-loading countermeasure but further work is needed to develop a solution that is more palatable and has fewer side effects.

  15. [Solubilization of nitrobenzene in micellar solutions of Tween 80 and inorganic salts].

    PubMed

    Li, Sui; Zhao, Yong-sheng; Xu, Wei; Dai, Ning

    2008-04-01

    The solubilization of nitrobenzene by a nonionic surfactant Tween 80 was investigated at 10 degrees C. Experimental results indicated that the solubility of nitrobenzene in water was greatly enhanced by Tween 80 at surfactant concentration above CMC(critical micelle concentration) and a linear relationship was obtained between surfactant concentration and nitrobenzene concentration from the solubility curve. The molar solubilization ratio (MSR) value was 5.093 and IgKm was 3.499. The solubilization was attributed to the ethoxylation group in Tween 80 micellar. Effect of four inorganic salts such as NaCl, KCl, CaCl2 , MgCl2 on water solubilities of nitrobenzene in Tween 80 micellar solutions was also investigated by a matrix of batch experiments. Mix the Tween 80-inorganic salts at the total mass ratios of 2:1, 5:1 and 10:1. The results show that the inorganic salts at a high concentration( > or = 500 mg x L(-1)) can enhance the solubilization capacities of Tween 80 micellar solution and increase the value of MSR and IgKm . Because of the salting-out effect between the micellar of Tween 80 and inorganic salts, the volume of micelle turns bigger, which may provide larger solubility volume for nitrobenzene. The mixture of nonionic surfactant and inorganic salts can be used in subsurface remediation as a flushing solution.

  16. Transition metal salt solutions and anaerobic adhesives in dental bonding.

    PubMed

    Ireland, A J; Sherriff, M

    1999-07-01

    The objectives of this experiment were twofold. Firstly to determine whether an anaerobic adhesive could be used to bond steel attachments to etched human enamel, following treatment of this surface with various concentrations of copper (II) sulphate solution. Secondly, to determine the effect of 0.05 M solutions of other transition metal sulphates and chlorides on the same bonding process. Stainless steel attachments were bonded to human enamel using an anaerobic adhesive. In each case the enamel, which had been ground flat, was etched with 37% o-phosphoric acid and then treated with copper (II) sulphate solution prior to bonding. After bench curing for one hour, the specimens were shear tested to failure, and the load at bebond recorded in each case. The effect of varying the concentration of copper (II) sulphate solution was determined. Following determination of the optimal copper (II) sulphate concentration, the experiment was repeated using the same concentration of various other transition metal sulphates and chlorides. The results were analysed using mean force to debond (N) and 95% confidence intervals. Kaplan-Meier survival probabilities and log-rank tests were also performed. Under the conditions of this experiment the optimal concentration of copper (II) sulphate solution was found to be 0.05 M. Of the various transition metal sulphates and chlorides under test, the sulphates appeared to provide a more active surface for the polymerisation of the anaerobic adhesive than the chlorides. Of the sulphate solutions, the most effective was that of copper. Anaerobic adhesives show promise as dental bonding agents capable of bonding metal attachments to enamel following enamel pretreatment with 0.05 M copper (II) sulphate solution.

  17. Hydrogen Sulfide Regulates Salt Tolerance in Rice by Maintaining Na+/K+ Balance, Mineral Homeostasis and Oxidative Metabolism Under Excessive Salt Stress

    PubMed Central

    Mostofa, Mohammad G.; Saegusa, Daisuke; Fujita, Masayuki; Tran, Lam-Son Phan

    2015-01-01

    Being a salt sensitive crop, rice growth and development are frequently affected by soil salinity. Hydrogen sulfide (H2S) has been recently explored as an important priming agent regulating diverse physiological processes of plant growth and development. Despite its enormous prospects in plant systems, the role of H2S in plant stress tolerance is still elusive. Here, a combined pharmacological, physiological and biochemical approach was executed aiming to examine the possible mechanism of H2S in enhancement of rice salt stress tolerance. We showed that pretreating rice plants with H2S donor sodium bisulfide (NaHS) clearly improved, but application of H2S scavenger hypotaurine with NaHS decreased growth and biomass-related parameters under salt stress. NaHS-pretreated salt-stressed plants exhibited increased chlorophyll, carotenoid and soluble protein contents, as well as suppressed accumulation of reactive oxygen species (ROS), contributing to oxidative damage protection. The protective mechanism of H2S against oxidative stress was correlated with the elevated levels of ascorbic acid, glutathione, redox states, and the enhanced activities of ROS- and methylglyoxal-detoxifying enzymes. Notably, the ability to decrease the uptake of Na+ and the Na+/K+ ratio, as well as to balance mineral contents indicated a role of H2S in ion homeostasis under salt stress. Altogether, our results highlight that modulation of the level of endogenous H2S genetically or exogenously could be employed to attain better growth and development of rice, and perhaps other crops, under salt stress. Furthermore, our study reveals the importance of the implication of gasotransmitters like H2S for the management of salt stress, thus assisting rice plants to adapt to adverse environmental changes. PMID:26734015

  18. Salting-out effect in aqueous NaCl solutions: trends with size and polarity of solute molecules.

    PubMed

    Endo, Satoshi; Pfennigsdorff, Andrea; Goss, Kai-Uwe

    2012-02-07

    Salting-out in aqueous NaCl solutions is relevant for the environmental behavior of organic contaminants. In this study, Setschenow (or salting-out) coefficients (K(s) [M(-1)]) for 43 diverse neutral compounds in NaCl solutions were measured using a shared headspace passive dosing method and a negligible depletion solid phase microextraction technique. The results were used to calibrate and evaluate estimation models for K(s). The molar volume of the solute correlated only moderately with K(s) (R(2) = 0.49, SD = 0.052). The polyparameter linear free energy relationship (pp-LFER) model that uses five compound descriptors resulted in a more accurate fit to our data (R(2) = 0.83, SD = 0.031). The pp-LFER analysis revealed that Na(+) and Cl(-) in aqueous solutions increase the cavity formation energy cost and the polar interaction energies toward neutral organic solutes. Accordingly, the salting-out effect increases with the size and decreases with the polarity of the solute molecule. COSMO-RS, a quantum mechanics-based fully predictive model, generally overpredicted the experimental K(s), but the predicted values were moderately correlated with the experimental values (R(2) = 0.66, SD = 0.042). Literature data (n = 93) were predicted by the calibrated pp-LFER and COSMO-RS models with root mean squared errors of 0.047 and 0.050, respectively. This study offers prediction models to estimate K(s), allowing implementation of the salting-out effect in contaminant fate models, linkage of various partition coefficients (such as air-water, sediment-water, and extraction phase-water partition coefficients) measured for fresh water and seawater, and estimation of enhancement of extraction efficiency in analytical procedures.

  19. Issues affecting storage of compressed air in solution-mined salt cavities

    SciTech Connect

    Allen, R.D.; Doherty, T.J.; Thoms, R.L.

    1982-04-01

    Geologic factors affecting salt deposit acceptability for CAES include diameter, depth, thickness, mineralogy, strength, faulting, seismic susceptibility, caprock quality and rate of dissolution by ground water. Assessment of a site involves analysis of existing information, seismic surveying, exploratory drilling, salt and caprock examination, geophysical logging, in situ stress measurement, and determination of hydrologic impact. Geologic exploration and solution mining at Huntorf, Federal Republic of Germany, are discussed. Cavern design parameters include octahedral shear strength, excess lateral stress, depth to cavern top, lateral salt thickness, vertical salt thickness, span, and height-to-diameter ratio. Noncompensated cavern operation involves cycling with respect to temperature, pressure, humidity and water. Cavern, borehole and surface monitoring methods are discussed.

  20. Acemetacin cocrystals and salts: structure solution from powder X-ray data and form selection of the piperazine salt.

    PubMed

    Sanphui, Palash; Bolla, Geetha; Nangia, Ashwini; Chernyshev, Vladimir

    2014-03-01

    Acemetacin (ACM) is a non-steroidal anti-inflammatory drug (NSAID), which causes reduced gastric damage compared with indomethacin. However, acemetacin has a tendency to form a less soluble hydrate in the aqueous medium. We noted difficulties in the preparation of cocrystals and salts of acemetacin by mechanochemical methods, because this drug tends to form a hydrate during any kind of solution-based processing. With the objective to discover a solid form of acemetacin that is stable in the aqueous medium, binary adducts were prepared by the melt method to avoid hydration. The coformers/salt formers reported are pyridine carboxamides [nicotinamide (NAM), isonicotinamide (INA), and picolinamide (PAM)], caprolactam (CPR), p-aminobenzoic acid (PABA), and piperazine (PPZ). The structures of an ACM-INA cocrystal and a binary adduct ACM-PABA were solved using single-crystal X-ray diffraction. Other ACM cocrystals, ACM-PAM and ACM-CPR, and the piperazine salt ACM-PPZ were solved from high-resolution powder X-ray diffraction data. The ACM-INA cocrystal is sustained by the acid⋯pyridine heterosynthon and N-H⋯O catemer hydrogen bonds involving the amide group. The acid⋯amide heterosynthon is present in the ACM-PAM cocrystal, while ACM-CPR contains carboxamide dimers of caprolactam along with acid-carbonyl (ACM) hydrogen bonds. The cocrystals ACM-INA, ACM-PAM and ACM-CPR are three-dimensional isostructural. The carboxyl⋯carboxyl synthon in ACM-PABA posed difficulty in assigning the position of the H atom, which may indicate proton disorder. In terms of stability, the salts were found to be relatively stable in pH 7 buffer medium over 24 h, but the cocrystals dissociated to give ACM hydrate during the same time period. The ACM-PPZ salt and ACM-nicotinamide cocrystal dissolve five times faster than the stable hydrate form, whereas the ACM-PABA adduct has 2.5 times faster dissolution rate. The pharmaceutically acceptable piperazine salt of acemetacin exhibits superior

  1. Acemetacin cocrystals and salts: structure solution from powder X-ray data and form selection of the piperazine salt

    PubMed Central

    Sanphui, Palash; Bolla, Geetha; Nangia, Ashwini; Chernyshev, Vladimir

    2014-01-01

    Acemetacin (ACM) is a non-steroidal anti-inflammatory drug (NSAID), which causes reduced gastric damage compared with indomethacin. However, acemetacin has a tendency to form a less soluble hydrate in the aqueous medium. We noted difficulties in the preparation of cocrystals and salts of acemetacin by mechanochemical methods, because this drug tends to form a hydrate during any kind of solution-based processing. With the objective to discover a solid form of acemetacin that is stable in the aqueous medium, binary adducts were prepared by the melt method to avoid hydration. The coformers/salt formers reported are pyridine carboxamides [nicotinamide (NAM), isonicotinamide (INA), and picolinamide (PAM)], caprolactam (CPR), p-aminobenzoic acid (PABA), and piperazine (PPZ). The structures of an ACM–INA cocrystal and a binary adduct ACM–PABA were solved using single-crystal X-ray diffraction. Other ACM cocrystals, ACM–PAM and ACM–CPR, and the piperazine salt ACM–PPZ were solved from high-resolution powder X-ray diffraction data. The ACM–INA cocrystal is sustained by the acid⋯pyridine heterosynthon and N—H⋯O catemer hydrogen bonds involving the amide group. The acid⋯amide heterosynthon is present in the ACM–PAM cocrystal, while ACM–CPR contains carboxamide dimers of caprolactam along with acid–carbonyl (ACM) hydrogen bonds. The cocrystals ACM–INA, ACM–PAM and ACM–CPR are three-dimensional isostructural. The carboxyl⋯carboxyl synthon in ACM–PABA posed difficulty in assigning the position of the H atom, which may indicate proton disorder. In terms of stability, the salts were found to be relatively stable in pH 7 buffer medium over 24 h, but the cocrystals dissociated to give ACM hydrate during the same time period. The ACM–PPZ salt and ACM–nicotinamide cocrystal dissolve five times faster than the stable hydrate form, whereas the ACM–PABA adduct has 2.5 times faster dissolution rate. The pharmaceutically acceptable piperazine

  2. Ion aggregation in high salt solutions. VI. Spectral graph analysis of chaotropic ion aggregates

    NASA Astrophysics Data System (ADS)

    Choi, Jun-Ho; Cho, Minhaeng

    2016-11-01

    Carrying out molecular dynamics simulations and graph theoretical analyses of high salt solutions, and comparing numerically calculated vibrational spectroscopic properties of water with femtosecond IR pump-probe experimental data, we have recently found that ions in high salt solutions can form two morphologically different ion aggregate structures. In the cases of NaCl solutions, Na+ and Cl- tend to form compact cluster-like ion aggregate in high NaCl solutions. In contrast, K+ and SCN- form spatially extended network-like ion aggregates that also exhibit a percolating network behavior. Interestingly, a variety of graph theoretical properties of ion network in high KSCN solutions were found to be very similar to those of water H-bonding network. It was shown that spatially extended ion networks in high KSCN solutions are completely intertwined with water H-bonding networks, which might be the key to understand the high solubility of thiocyanate salts in water. Here, we further consider two salts that have been extensively studied experimentally by using femtosecond IR pump-probe technique, which are NaClO4 and NaBF4. Note that ClO4 - and BF4 - are well-known chaotropic ions that have been believed to behave as water structure breaker. To understand how such chaotropic ions affect water H-bonding structure, we carried out spectral graph analyses of molecular dynamics simulation data of these aqueous solutions. Graph spectra and degree distribution of ion aggregates formed in high NaBF4 and NaClO4 solutions show that these chaotropic anions also have a strong propensity to form ion networks. The fact that salts containing chaotropic ions like SCN-, BF4 - , and ClO4 - have very high solubility limits in water could then be related to our observation that these chaotropic anions with counter cations in high salt solutions are capable of forming intricate ion networks intertwined with water H-bonding networks. We anticipate that the present graph theoretical analysis

  3. Changes in Proton Dynamics in Articular Cartilage Caused by Phosphate Salts and Fixation Solutions.

    PubMed

    Zheng, Shaokuan; Xia, Yang

    2010-01-01

    The objective was to study the effect of phosphate salts and fixation solutions on the proton dynamics in articular cartilage in vitro. Microscopic magnetic resonance imaging (μMRI) T(2) anisotropy and nuclear magnetic resonance (NMR) double quantum-filtered (DQF) spectroscopy were used to study the full-thickness articular cartilage from several canine humeral heads. The in-plane pixel size across the depth of the cartilage tissue was 13 μm. The acid phosphate salt was an effective exchange catalyst for proton exchange in the cartilage with an organized structure of collagen fibrils, while the alkaline phosphate salt was not. For cartilage tissue containing less organized collagen fibrils, both acid and alkaline phosphate salts have no significant effect on the T(2) value at low concentration but decrease the T(2) value at high concentration. The solutions of NaCl, KCl, CaCl(2), and D-PBS were found to have no significant effect on T(2) and DQF in cartilage. This study demonstrates the ability to modify the proton exchange in articular cartilage using the solutions of phosphate salts. The ability to modify the proton exchange in articular cartilage can be used to modulate the laminar appearance of articular cartilage in MRI.

  4. Protoplasts Surviving Freezing to −196 C and Osmotic Dehydration in 5 Molar Salt Solutions Prepared from the Bark of Winter Black Locust Trees 1

    PubMed Central

    Siminovitch, David

    1979-01-01

    Free protoplasts were prepared from the living bark tissue of the trunk of summer and winter black locust trees by enzymic digestion of thin slices of the tissue for 3 hours in a medium containing 2% Onozuka cellulase, 2% Rhozyme pectinase, and 2% Driselase in mannitol solutions using 0.4 molar mannitol for summer tissue and 1.0 molar mannitol for winter tissues. Cleaned suspensions of protoplasts and also thin slices of tissue with cells intact were frozen to temperatures of −10 C, −20 C, −30 C, −40 C and liquid nitrogen in sucrose and balanced salt solutions. Similar suspensions of protoplasts were also subjected to strong osmotic dehydration (plasmorrhysis) in a series of balanced salt solutions of increasing molarity. Tests for survival showed that protoplasts retain the same properties of either extreme susceptibility or extreme resistance to injury by freezing or osmotic dehydration as the cells from which they are prepared. Winter protoplasts showed capability for tolerating freezing to −196 C and plasmorrhysis in 5 molar salt solutions. These results indicate that protoplasts are a valid and useful system for investigating the properties of the protoplasm and surface membranes associated with the seasonal development of extreme hardiness in the cells of woody plants. Images PMID:16660800

  5. Characterization of Laboratory Prepared Concrete Pastes Exposed to High Alkaline and High Sodium Salt Solutions

    SciTech Connect

    Langton, C. A.

    2016-06-30

    The objective of this study was to identify potential chemical degradation mechanisms for the Saltstone Disposal Unit (SDU) concretes, which over the performance life of the structures may be exposed to highly alkaline sodium salt solutions containing sulfate, hydroxide, and other potentially corrosive chemicals in salt solution and saltstone flush water, drain water, leachate and / or pore solution. The samples analyzed in this study were cement pastes prepared in the SIMCO Technologies, Inc. concrete laboratory. They were based on the paste fractions of the concretes used to construct the Saltstone Disposal Units (SDUs). SDU 1 and 4 concrete pastes were represented by the PV1 test specimens. The paste in the SDU 2, 3, 5, and 6 concrete was represented by the PV2 test specimens. SIMCO Technologies, Inc. selected the chemicals and proportions in the aggressive solutions to approximate proportions in the saltstone pore solution [2, 3, 5, and 6]. These test specimens were cured for 56 days in curing chamber before being immersed in aggressive solutions. After exposure, the samples were frozen to prevent additional chemical transport and reaction. Selected archived (retrieved from the freezer) samples were sent to the Savannah River National Laboratory (SRNL) for additional characterization using x-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive x-ray (EDX) spectroscopy. Characterization results are summarized in this report. In addition, a correlation between the oxide composition of the pastes and their chemical durability in the alkaline salt solutions is provided.

  6. A new class of draw solutions for minimizing reverse salt flux to improve forward osmosis desalination.

    PubMed

    Nguyen, Hau Thi; Nguyen, Nguyen Cong; Chen, Shiao-Shing; Ngo, Huu Hao; Guo, Wenshan; Li, Chi-Wang

    2015-12-15

    The applications of forward osmosis (FO) have been hindered because of the lack of an optimal draw solution. The reverse salt flux from the draw solution not only reduces the water flux but also increases the cost of draw solute replenishment. Therefore, in this study, Tergitol NP7 and NP9 with a long straight carbon chain and low critical micelle concentration (CMC) were coupled with highly charged ethylenediaminetetraacetic acid (EDTA) as an innovative draw solution to minimize reverse salt diffusion in FO for the first time. The results showed that the lowest reverse salt flux of 0.067 GMH was observed when 0.1M EDTA-2Na coupled with 15mM NP7 was used as a draw solution and deionized water was used as a feed solution in FO mode (active layer facing with the feed solution). This is due to the hydrophobic interaction between the tails of NP7 and the FO membrane, thus creating layers on the membrane surface and constricting the FO membrane pores. Moreover, 1M EDTA-2Na coupled with 15mM NP7 is promising as an optimal draw solution for brackish water and sea water desalination. Average water fluxes of 7.68, 6.78, and 5.95 LMH were achieved when brackish water was used as a feed solution (5, 10, and 20g/L NaCl), and an average water flux of 3.81 LMH was achieved when sea water was used as a feed solution (35g/L NaCl). The diluted draw solution was recovered using a nanofiltration (NF-TS80) membrane with a high efficiency of 95% because of the high charge and large size of the draw solution. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Thermodynamics of extraction by solutions of amines and salts of substituted ammonium bases

    NASA Astrophysics Data System (ADS)

    Ochkin, A. V.; Sergievskii, V. V.

    1989-09-01

    Extraction systems containing amines and their salts are widely used to concentrate and separate metals. From the theoretical viewpoint, these systems are among the most complex, because of the variety of intermolecular interactions in the organic phase. The explanation and quantitative description of the observed regularities of extraction became possible only as a result of progress in the study of the thermodynamics of binary and multicomponent solutions of salts of substituted ammonium bases in non-polar organic solvents, which make it possible to distinguish the contribution of each type of interaction to the non-ideal character of the solutions. All known "anomalous" features are due to the influence of the hydration of the salts of the substituted ammonium bases on their activity. The bibliography contains 113 references.

  8. Electrochemical Recovery of Sodium Hydroxide from Alkaline Salt Solution

    SciTech Connect

    Hobbs, D.T.; Edwards, T.B.

    1996-10-01

    A statistically designed set of tests determined the effects of current density, temperature, and the concentrations of nitrate/nitrite, hydroxide and aluminate on the recovery of sodium as sodium hydroxide (caustic) from solutions simulating those produced from the Savannah River Site (SRS) In-Tank Precipitation process. These tests included low nitrate and nitrite concentrations which would be produced by electrolytic nitrate/nitrite destruction. The tests used a two compartment electrochemical cell with a Nafion Type 324 ion-exchange membrane. Caustic was successfully recovered from the waste solutions. Evaluation of the testing results indicated that the transport of sodium across the membrane was not significantly affected by any of the varied parameters. The observed variance in the sodium flux is attributed to experimental errors and variations in the performance characteristics of individual pieces of the organic-based Nafion membrane.Additional testing is recommended to determine the maximum current density, to evaluate the chemical durability of the organic membrane as a function of current density and to compare the durability and performance characteristics of the organic-based Nafion membrane with that of other commercially available organic membranes and the inorganic class of membranes under development by Ceramatec and PNNL.

  9. Raman studies of solutions of single-wall carbon nanotube salts.

    PubMed

    Anglaret, E; Dragin, F; Pénicaud, A; Martel, R

    2006-03-09

    Polyelectrolyte solutions of Na-doped single-wall carbon nanotube (SWNT) salts are studied by Raman spectroscopy. Their Raman signature is first compared to undoped SWNT suspensions and dry alkali-doped SWNT powders, and the results indicate that the nanotube solutions consist of heavily doped (charged) SWNT. Raman signature of doping is then used to monitor in situ the oxidation reaction of the nanotube salt solutions upon exposure to air and to an acceptor molecule (benzoquinone). The results indicate a direct charge-transfer reaction from the acceptor molecule to the SWNT, leading to their gradual charge neutralization and eventual precipitation in solution. The results are consistent with a simple redox titration process occurring at the thermodynamical equilibrium.

  10. Results of Analysis of Macrobatch 3 Decontaminated Salt Solution Coalescer from May 2010

    SciTech Connect

    Peters, T. B.; Fink, S. D.

    2012-12-18

    SRNL analyzed the Decontamination Salt Solution (DSS) coalescer from MCU by several analytical methods. This unit was removed from service in May 2010. The results of these analyses indicate that there is very little evidence of fouling via excessive solids, either from the leaching studies or X-Ray Diffraction (XRD) analysis.

  11. Mechanism of Pitting Corrosion Prevention by Nitrite in Carbon Steel Exposed to Dilute Salt Solutions

    SciTech Connect

    Zapp, P.E.

    2002-05-02

    The overall goal of this project was to develop a detailed understanding of the role of nitrite in preventing the breakdown of protective oxide on steel and on the onset of pitting, by considering the interactions of the oxidation and reduction reactions that may occur in alkaline salt solutions.

  12. Oxygen isotope activities and concentrations in aqueous salt solutions at elevated temperatures: Consequences for isotope geochemistry

    USGS Publications Warehouse

    Truesdell, A.H.

    1974-01-01

    Studies of the effect of dissolved salts on the oxygen isotope activity ratio of water have been extended to 275??C. Dehydrated salts were added to water of known isotope composition and the solutions were equilibrated with CO2 which was sampled for analysis. For comparison similar studies were made using pure water. Results on water nearly coincide with earlier calculations. Salt effects diminish with increasing temperature only for solutions of MgCl2 and LiCl. Other salt solutions show complex behavior due to the temperature-dependent formation of ion pairs of changing character. Equilibrium fractionations (103 ln ??) between 1 molal solutions and pure water at 25, 100, and 275??C are: NaCl 0.0, -1.5, +1.0; KCl 0.0, -1.0, +2.0; LiCl -1.0, -0.6, -0.5; CaCl2 -0.4, -1.8, +0.8; MgCl2 -1.1, -0.7, -0.3; MgSO4 -1.1, +0.1, -; NaF (0.8 m) 0.0, -1.5, -0.3; and NH4Cl (0.55 m) 0.0, -1.2, -1.3. These effects are significant in the isotope study of hot saline fluids responsible for ore deposition and of fluids found in certain geothermal systems. Minor modification of published isotope geothermometers may be required. ?? 1974.

  13. Methods for predicting properties and tailoring salt solutions for industrial processes

    NASA Technical Reports Server (NTRS)

    Ally, Moonis R.

    1993-01-01

    An algorithm developed at Oak Ridge National Laboratory accurately and quickly predicts thermodynamic properties of concentrated aqueous salt solutions. This algorithm is much simpler and much faster than other modeling schemes and is unique because it can predict solution behavior at very high concentrations and under varying conditions. Typical industrial applications of this algorithm would be in manufacture of inorganic chemicals by crystallization, thermal storage, refrigeration and cooling, extraction of metals, emissions controls, etc.

  14. Methods for predicting properties and tailoring salt solutions for industrial processes

    SciTech Connect

    Ally, M.R.

    1992-01-01

    An algorithm developed at Oak Ridge National Laboratory accurately and quickly predicts thermodynamic properties of concentrated aqueous salt solutions. This algorithm is much simpler and much faster than other modeling schemes and is unique because it can predict solution behavior at very high concentrations and under varying conditions. Typical industrial applications of this algorithm would be in manufacture of inorganic chemicals by crystallization, thermal storage, refrigeration and cooling, extraction of metals, emissions control, etc. 3 figs, 2 tabs, 1 ref.

  15. Explicit-water theory for the salt-specific effects and Hofmeister series in protein solutions

    PubMed Central

    Kalyuzhnyi, Yuriy V.; Vlachy, Vojko

    2016-01-01

    Effects of addition of salts on stability of aqueous protein solutions are studied theoretically and the results are compared with experimental data. In our approach, all the interacting species, proteins, ions, and water molecules, are accounted for explicitly. Water molecules are modeled as hard spheres with four off-center attractive square-well sites. These sites serve to bind either another water or to solvate the ions or protein charges. The ions are represented as charged hard spheres, and decorated by attractive sites to allow solvation. Spherical proteins simultaneously possess positive and negative groups, represented by charged hard spheres, attached to the surface of the protein. The attractive square-well sites, mimicking the protein–protein van der Waals interaction, are located on the surface of the protein. To obtain numerical results, we utilized the energy route of Wertheim’s associative mean spherical approximation. From measurable properties, we choose to calculate the second virial coefficient B2, which is closely related to the tendency of proteins to aggregate and eventually crystalize. Calculations are in agreement with experimental trends: (i) For low concentration of added salt, the alkali halide salts follow the inverse Hofmeister series. (ii) At higher concentration of added salt, the trend is reversed. (iii) When cations are varied, the salts follow the direct Hofmeister series. (iv) In contrast to the colloidal theories, our approach correctly predicts the non-monotonic behavior of B2 upon addition of salts. (v) With respect to anions, the theory predicts for the B2 values to follow different sequences below and above the iso-ionic point, as also confirmed experimentally. (vi) A semi-quantitative agreement between measured and calculated values for the second virial coefficient, as functions of pH of solution and added salt type and concentration, is obtained. PMID:27276970

  16. Explicit-water theory for the salt-specific effects and Hofmeister series in protein solutions

    NASA Astrophysics Data System (ADS)

    Kalyuzhnyi, Yuriy V.; Vlachy, Vojko

    2016-06-01

    Effects of addition of salts on stability of aqueous protein solutions are studied theoretically and the results are compared with experimental data. In our approach, all the interacting species, proteins, ions, and water molecules, are accounted for explicitly. Water molecules are modeled as hard spheres with four off-center attractive square-well sites. These sites serve to bind either another water or to solvate the ions or protein charges. The ions are represented as charged hard spheres, and decorated by attractive sites to allow solvation. Spherical proteins simultaneously possess positive and negative groups, represented by charged hard spheres, attached to the surface of the protein. The attractive square-well sites, mimicking the protein-protein van der Waals interaction, are located on the surface of the protein. To obtain numerical results, we utilized the energy route of Wertheim's associative mean spherical approximation. From measurable properties, we choose to calculate the second virial coefficient B2, which is closely related to the tendency of proteins to aggregate and eventually crystalize. Calculations are in agreement with experimental trends: (i) For low concentration of added salt, the alkali halide salts follow the inverse Hofmeister series. (ii) At higher concentration of added salt, the trend is reversed. (iii) When cations are varied, the salts follow the direct Hofmeister series. (iv) In contrast to the colloidal theories, our approach correctly predicts the non-monotonic behavior of B2 upon addition of salts. (v) With respect to anions, the theory predicts for the B2 values to follow different sequences below and above the iso-ionic point, as also confirmed experimentally. (vi) A semi-quantitative agreement between measured and calculated values for the second virial coefficient, as functions of pH of solution and added salt type and concentration, is obtained.

  17. Hydration structure of salt solutions from ab initio molecular dynamics

    SciTech Connect

    Bankura, Arindam; Carnevale, Vincenzo; Klein, Michael L.

    2013-01-07

    The solvation structures of Na{sup +}, K{sup +}, and Cl{sup -} ions in aqueous solution have been investigated using density functional theory (DFT) based Car-Parrinello (CP) molecular dynamics (MD) simulations. CPMD trajectories were collected for systems containing three NaCl or KCl ion pairs solvated by 122 water molecules using three different but commonly employed density functionals (BLYP, HCTH, and PBE) with electron correlation treated at the level of the generalized gradient approximation (GGA). The effect of including dispersion forces was analyzed through the use of an empirical correction to the DFT-GGA scheme. Special attention was paid to the hydration characteristics, especially the structural properties of the first solvation shell of the ions, which was investigated through ion-water radial distribution functions, coordination numbers, and angular distribution functions. There are significant differences between the present results obtained from CPMD simulations and those provided by classical MD based on either the CHARMM force field or a polarizable model. Overall, the computed structural properties are in fair agreement with the available experimental results. In particular, the observed coordination numbers 5.0-5.5, 6.0-6.4, and 6.0-6.5 for Na{sup +}, K{sup +}, and Cl{sup -}, respectively, are consistent with X-ray and neutron scattering studies but differ somewhat from some of the many other recent computational studies of these important systems. Possible reasons for the differences are discussed.

  18. Hydration structure of salt solutions from ab initio molecular dynamics

    NASA Astrophysics Data System (ADS)

    Bankura, Arindam; Carnevale, Vincenzo; Klein, Michael L.

    2013-01-01

    The solvation structures of Na^+, K^+, and Cl^- ions in aqueous solution have been investigated using density functional theory (DFT) based Car-Parrinello (CP) molecular dynamics (MD) simulations. CPMD trajectories were collected for systems containing three NaCl or KCl ion pairs solvated by 122 water molecules using three different but commonly employed density functionals (BLYP, HCTH, and PBE) with electron correlation treated at the level of the generalized gradient approximation (GGA). The effect of including dispersion forces was analyzed through the use of an empirical correction to the DFT-GGA scheme. Special attention was paid to the hydration characteristics, especially the structural properties of the first solvation shell of the ions, which was investigated through ion-water radial distribution functions, coordination numbers, and angular distribution functions. There are significant differences between the present results obtained from CPMD simulations and those provided by classical MD based on either the CHARMM force field or a polarizable model. Overall, the computed structural properties are in fair agreement with the available experimental results. In particular, the observed coordination numbers 5.0-5.5, 6.0-6.4, and 6.0-6.5 for Na^+, K^+, and Cl^-, respectively, are consistent with X-ray and neutron scattering studies but differ somewhat from some of the many other recent computational studies of these important systems. Possible reasons for the differences are discussed.

  19. Hydration structure of salt solutions from ab initio molecular dynamics.

    PubMed

    Bankura, Arindam; Carnevale, Vincenzo; Klein, Michael L

    2013-01-07

    The solvation structures of Na(+), K(+), and Cl(-) ions in aqueous solution have been investigated using density functional theory (DFT) based Car-Parrinello (CP) molecular dynamics (MD) simulations. CPMD trajectories were collected for systems containing three NaCl or KCl ion pairs solvated by 122 water molecules using three different but commonly employed density functionals (BLYP, HCTH, and PBE) with electron correlation treated at the level of the generalized gradient approximation (GGA). The effect of including dispersion forces was analyzed through the use of an empirical correction to the DFT-GGA scheme. Special attention was paid to the hydration characteristics, especially the structural properties of the first solvation shell of the ions, which was investigated through ion-water radial distribution functions, coordination numbers, and angular distribution functions. There are significant differences between the present results obtained from CPMD simulations and those provided by classical MD based on either the CHARMM force field or a polarizable model. Overall, the computed structural properties are in fair agreement with the available experimental results. In particular, the observed coordination numbers 5.0-5.5, 6.0-6.4, and 6.0-6.5 for Na(+), K(+), and Cl(-), respectively, are consistent with X-ray and neutron scattering studies but differ somewhat from some of the many other recent computational studies of these important systems. Possible reasons for the differences are discussed.

  20. Electrodialysis for recovering salts from a urine solution containing micropollutants.

    PubMed

    Pronk, Wouter; Biebow, Martin; Boller, Markus

    2006-04-01

    Electrodialysis was investigated for the separation of micropollutants from nutrients in anthropogenic urine. In a continuously operated process, the nutrients were concentrated up to a factor of 3.2. The concentration factor was limited by water transport across the membrane. Water transport was caused by osmosis and electroosmosis, and a model was developed to describe these phenomena. The removal of several spiked micropollutants was investigated in continuous electrodialysis experiments. Ethinylestradiol was removed completely during the whole operating period. Diclofenac and carbamazepine were initially retained, but limited permeation (5-10%) occurred after longer operating times (90 days). Retentions of propranolol and ibuprofen were also high initially, but substantial breakthroughs occurred during extended operation. Considerable adsorption on the membranes was observed for all compounds. The permeation mechanism of several compounds appears to depend on the adsorbed amount on the membrane, which indicates that partitioning and diffusion mechanisms play an important role in the permeation transport. Partial desorption occurred in leaching experiments with polarity reversal, and almost quantitative desorption was observed after incubation of the membranes with Filter Count Gel Solution. Because environmental concentrations are much lower than the concentrations spiked here, it can be anticipated that operation without significant permeation is possible in practice during extended periods of time.

  1. Salt-Inducible Kinase 3 Provides Sugar Tolerance by Regulating NADPH/NADP(+) Redox Balance.

    PubMed

    Teesalu, Mari; Rovenko, Bohdana M; Hietakangas, Ville

    2017-02-06

    Nutrient-sensing pathways respond to changes in the levels of macronutrients, such as sugars, lipids, or amino acids, and regulate metabolic pathways to maintain organismal homeostasis [1, 2]. Consequently, nutrient sensing provides animals with the metabolic flexibility necessary for enduring temporal fluctuations in nutrient intake. Recent studies have shown that an animal's ability to survive on a high-sugar diet is determined by sugar-responsive gene regulation [3-8]. It remains to be elucidated whether other levels of metabolic control, such as post-translational regulation of metabolic enzymes, also contribute to organismal sugar tolerance. Furthermore, the sugar-regulated metabolic pathways contributing to sugar tolerance remain insufficiently characterized. Here, we identify Salt-inducible kinase 3 (SIK3), a member of the AMP-activated protein kinase (AMPK)-related kinase family, as a key determinant of Drosophila sugar tolerance. SIK3 allows sugar-feeding animals to increase the reductive capacity of nicotinamide adenine dinucleotide phosphate (NADPH/NADP(+)). NADPH mediates the reduction of the intracellular antioxidant glutathione, which is essential for survival on a high-sugar diet. SIK3 controls NADP(+) reduction by phosphorylating and activating Glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the pentose phosphate pathway. SIK3 gene expression is regulated by the sugar-regulated transcription factor complex Mondo-Mlx, which was previously identified as a key determinant of sugar tolerance. SIK3 converges with Mondo-Mlx in sugar-induced activation of G6PD, and simultaneous inhibition of SIK3 and Mondo-Mlx leads to strong synergistic lethality on a sugar-containing diet. In conclusion, SIK3 cooperates with Mondo-Mlx to maintain organismal sugar tolerance through the regulation of NADPH/NADP(+) redox balance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Effects of salt stress on ion balance and nitrogen metabolism of old and young leaves in rice (Oryza sativa L.)

    PubMed Central

    2012-01-01

    Background It is well known that salt stress has different effects on old and young tissues. However, it remains largely unexplored whether old and young tissues have different regulatory mechanism during adaptation of plants to salt stress. The aim of this study was to investigate whether salt stress has different effects on the ion balance and nitrogen metabolism in the old and young leaves of rice, and to compare functions of both organs in rice salt tolerance. Results Rice protected young leaves from ion harm via the large accumulation of Na+ and Cl− in old leaves. The up-regulation of OsHKT1;1, OsHAK10 and OsHAK16 might contribute to accumulation of Na+ in old leaves under salt stress. In addition, lower expression of OsHKT1;5 and OsSOS1 in old leaves may decrease frequency of retrieving Na+ from old leaf cells. Under salt stress, old leaves showed higher concentration of NO3− content than young leaves. Up-regulation of OsNRT1;2, a gene coding nitrate transporter, might contribute to the accumulation of NO3− in the old leaves of salt stressed-rice. Salt stress clearly up-regulated the expression of OsGDH2 and OsGDH3 in old leaves, while strongly down-regulated expression of OsGS2 and OsFd-GOGAT in old leaves. Conclusions The down-regulation of OsGS2 and OsFd-GOGAT in old leaves might be a harmful response to excesses of Na+ and Cl−. Under salt stress, rice might accumulate Na+ and Cl− to toxic levels in old leaves. This might influence photorespiration process, reduce NH4+ production from photorespiration, and immediately down-regulate the expression of OsGS2 and OsFd-GOGAT in old leaves of salt stressed rice. Excesses of Na+ and Cl− also might change the pathway of NH4+ assimilation in old leaves of salt stressed rice plants, weaken GOGAT/GS pathway and elevate GDH pathway. PMID:23082824

  3. A traditional Japanese-style salt field is a niche for haloarchaeal strains that can survive in 0.5% salt solution

    PubMed Central

    Fukushima, Tadamasa; Usami, Ron; Kamekura, Masahiro

    2007-01-01

    Background Most of the haloarchaeal strains have been isolated from hypersaline environments such as solar evaporation ponds, salt lakes, or salt deposits, and they, with some exceptions, lyse or lose viability in very low-salt concentrations. There are no salty environments suitable for the growth of haloarchaea in Japan. Although Natrialba asiatica and Haloarcula japonica were isolated many years ago, the question, "Are haloarchaea really thriving in natural environments of Japan?" has remained unanswered. Results Ten strains were isolated from a traditional Japanese-style salt field at Nie, Noto Peninsula, Japan by plating out the soil samples directly on agar plates containing 30% (w/v) salts and 0.5% yeast extract. They were most closely related to strains of three genera, Haladaptatus, Halococcus, and Halogeometricum. Survival rates in 3% and 0.5% SW (Salt Water, solutions containing salts in approximately the same proportions as found in seawater) solutions at 37°C differed considerably depending on the strains. Two strains belonging to Halogeometricum as well as the type strain Hgm. borinquense died and lysed immediately after suspension. Five strains that belonged to Halococcus and a strain that may be a member of Halogeometricum survived for 1–2 days in 0.5% SW solution. Two strains most closely related to Haladaptatus possessed extraordinary strong tolerance to low salt conditions. About 20 to 34% of the cells remained viable in 0.5% SW after 9 days incubation. Conclusion In this study we have demonstrated that haloarchaea are really thriving in the soil of Japanese-style salt field. The haloarchaeal cells, particularly the fragile strains are suggested to survive in the micropores of smaller size silt fraction, one of the components of soil. The inside of the silt particles is filled with concentrated salt solution and kept intact even upon suspension in rainwater. Possible origins of the haloarchaea isolated in this study are discussed. PMID

  4. Modeling Solute Thermokinetics in LiCI-KCI Molten Salt for Nuclear Waste Separation

    SciTech Connect

    Morgan, Dane; Eapen, Jacob

    2013-10-01

    Recovery of actinides is an integral part of a closed nuclear fuel cycle. Pyrometallurgical nuclear fuel recycling processes have been developed in the past for recovering actinides from spent metallic and nitride fuels. The process is essentially to dissolve the spent fuel in a molten salt and then extract just the actinides for reuse in a reactor. Extraction is typically done through electrorefining, which involves electrochemical reduction of the dissolved actinides and plating onto a cathode. Knowledge of a number of basic thermokinetic properties of salts and salt-fuel mixtures is necessary for optimizing present and developing new approaches for pyrometallurgical waste processing. The properties of salt-fuel mixtures are presently being studied, but there are so many solutes and varying concentrations that direct experimental investigation is prohibitively time consuming and expensive (particularly for radioactive elements like Pu). Therefore, there is a need to reduce the number of required experiments through modeling of salt and salt-fuel mixture properties. This project will develop first-principles-based molecular modeling and simulation approaches to predict fundamental thermokinetic properties of dissolved actinides and fission products in molten salts. The focus of the proposed work is on property changes with higher concentrations (up to 5 mol%) of dissolved fuel components, where there is still very limited experimental data. The properties predicted with the modeling will be density, which is used to assess the amount of dissolved material in the salt; diffusion coefficients, which can control rates of material transport during separation; and solute activity, which determines total solubility and reduction potentials used during electrorefining. The work will focus on La, Sr, and U, which are chosen to include the important distinct categories of lanthanides, alkali earths, and actinides, respectively. Studies will be performed using LiCl-KCl salt

  5. Stochastic solution of population balance equations for reactor networks

    SciTech Connect

    Menz, William J.; Akroyd, Jethro; Kraft, Markus

    2014-01-01

    This work presents a sequential modular approach to solve a generic network of reactors with a population balance model using a stochastic numerical method. Full-coupling to the gas-phase is achieved through operator-splitting. The convergence of the stochastic particle algorithm in test networks is evaluated as a function of network size, recycle fraction and numerical parameters. These test cases are used to identify methods through which systematic and statistical error may be reduced, including by use of stochastic weighted algorithms. The optimal algorithm was subsequently used to solve a one-dimensional example of silicon nanoparticle synthesis using a multivariate particle model. This example demonstrated the power of stochastic methods in resolving particle structure by investigating the transient and spatial evolution of primary polydispersity, degree of sintering and TEM-style images. Highlights: •An algorithm is presented to solve reactor networks with a population balance model. •A stochastic method is used to solve the population balance equations. •The convergence and efficiency of the reported algorithms are evaluated. •The algorithm is applied to simulate silicon nanoparticle synthesis in a 1D reactor. •Particle structure is reported as a function of reactor length and time.

  6. Salt-water-freshwater transient upconing - An implicit boundary-element solution

    USGS Publications Warehouse

    Kemblowski, M.

    1985-01-01

    The boundary-element method is used to solve the set of partial differential equations describing the flow of salt water and fresh water separated by a sharp interface in the vertical plane. In order to improve the accuracy and stability of the numerical solution, a new implicit scheme was developed for calculating the motion of the interface. The performance of this scheme was tested by means of numerical simulation. The numerical results are compared to experimental results for a salt-water upconing under a drain problem. ?? 1985.

  7. Precursor Luminescence near the Collapse of Laser-Induced Bubbles in Alkali-Salt Solutions

    PubMed Central

    Chu, Han-Ching; Vo, Sonny; Williams, Gary A.

    2014-01-01

    A precursor luminescence pulse consisting of atomic line emission is observed as much as 150 nanoseconds prior to the collapse point of laser-created bubbles in alkali-metal solutions. The timing of the emission from neutral Na, Li, and K atoms is strongly dependent on the salt concentration, which appears to result from resonant radiation trapping by the alkali atoms in the bubble. The alkali emission ends at the onset of the blackbody luminescence pulse at the bubble collapse point, and the duration of the blackbody pulse is found to be reduced by up to 30% as the alkali-salt concentration is increased. PMID:19519032

  8. Heat-induced formation of myosin oligomer-soluble filament complex in high-salt solution.

    PubMed

    Shimada, Masato; Takai, Eisuke; Ejima, Daisuke; Arakawa, Tsutomu; Shiraki, Kentaro

    2015-02-01

    Heat-induced aggregation of myosin into an elastic gel plays an important role in the water-holding capacity and texture of meat products. Here, we investigated thermal aggregation of porcine myosin in high-salt solution over a wide temperature range by dynamic light scattering experiments. The myosin samples were readily dissolved in 1.0 M NaCl at 25 °C followed by dilution into various salt concentrations. The diluted solutions consistently contained both myosin monomers and soluble filaments. The filament size decreased with increasing salt concentration and temperature. High temperatures above Tm led to at least partial dissociation of soluble filaments and thermal unfolding, resulting in the formation of soluble oligomers and binding to the persistently present soluble filaments. Such a complex formation between the oligomers and filaments has never been observed. Our results provide new insight into the heat-induced myosin gelation in high-salt solution. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Structure-activity relationship for hydrophobic salts as viscosity-lowering excipients for concentrated solutions of monoclonal antibodies.

    PubMed

    Guo, Zheng; Chen, Alvin; Nassar, Roger A; Helk, Bernhard; Mueller, Claudia; Tang, Yu; Gupta, Kapil; Klibanov, Alexander M

    2012-11-01

    To discover, elucidate the structure-activity relationship (SAR), and explore the mechanism of action of excipients able to drastically lower the viscosities of concentrated aqueous solutions of humanized monoclonal antibodies (MAbs). Salts prepared from hydrophobic cations and anions were dissolved into humanized MAbs solutions. Viscosities of the resulting solutions were measured as a function of the nature and concentration of the salts and MAbs. Even at moderate concentrations, some of the salts prepared herein were found to reduce over 10-fold the viscosities of concentrated aqueous solutions of several MAbs at room temperature. To be potent viscosity-lowering excipients, the ionic constituents of the salts must be hydrophobic, bulky, and aliphatic. A mechanistic hypothesis explaining the observed salt effects on MAb solutions' viscosities was proposed and verified.

  10. Fourteen-year survival of Pseudomonas cepacia in a salts solution preserved with benzalkonium chloride.

    PubMed Central

    Geftic, S G; Heymann, H; Adair, F W

    1979-01-01

    A strain of Pseudomonas cepacia that survived for 14 years (1963 to 1977) as a contaminant in an inorganic salt solution which contained commercial 0.05% benzalkonium chloride (CBC) as an antimicrobial preservative, was compared to a recent clinical isolate of P. cepacia. Ammonium acetate was present in the concentrated stock CBC solution, and served as a carbon and nitrogen source for growth when carried over into the salts solution with the CBC. The isolate's resistance to pure benzalkonium chloride was increased step-wise to a concentration of 16%. Plate counts showed 4 x 10(3) colony-forming units per ml in the salts solution. Comparison of growth rates, mouse virulence, antibiotics resistance spectra, and substrate requirements disclosed no differences between the contaminant and a recently isolated clinical strain of P. cepacia. The results indicate that it is critical that pharmaceutical solutions containing benzalkonium chloride as an antimicrobial preservative be formulated without extraneous carbon and nitrogen sources or be preserved with additional antimicrobial agents. PMID:453827

  11. Effect of perfusion of bile salts solutions into the oesophagus of hiatal hernia patients and controls.

    PubMed Central

    Bachir, G S; Collis, J L

    1976-01-01

    Tests of the response to perfusion of the oesophagus were made in 54 patients divided into three groups. Group I consisted of patients with symptomatic hiatal hernia, group II hiatal hernia patients with peptic stricture, and group III normal individuals. Each individual oesophagus was perfused at a rate of 45-65 drops per minute over 25 minutes with six solutions: normal saline, N/10 HCl, taurine conjugates of bile salts in normal saline, taurine conjugates of bile salts in N/10 HCl, glycine conjugates of bile salts in normal saline, and taurine and glycine conjugates in a ratio of 1 to 2 in normal saline. It was found that acidified taurine solutions were more irritating than acid alone. With a 2mM/l solution of taurine in acid, symptoms are produced even in controls. With a 1 mM/l solution of the same conjugates, the majority of normal people feel slight heartburn or nothing, and therefore perfusion into the oesophagus of such a solution could be used as a test for oesophagitis. PMID:941112

  12. Solution-derived sodalite made with Si- and Ge-ethoxide precursors for immobilizing electrorefiner salt

    NASA Astrophysics Data System (ADS)

    Riley, Brian J.; Lepry, William C.; Crum, Jarrod V.

    2016-01-01

    Chlorosodalite has the general form of Na8(AlSiO4)6Cl2 and this paper describes experiments conducted to synthesize sodalite with a solution-based approach to immobilize a simulated spent electrorefiner salt solution containing a mixture of alkali, alkaline earth, and lanthanide chlorides. The reactants used were the salt solution, NaAlO2, and either Si(OC2H5)4 or Ge(OC2H5)4. Additionally, seven different glass sintering aids (at loadings of 5 mass%) were evaluated as sintering aids for consolidating the as-made powders using a cold-press-and-sinter technique. This process of using alkoxide additives for the Group IV component can be used to produce large quantities of sodalite at near-room temperature as compared to a method where colloidal silica was used as the silica source. However, the small particle sizes inhibited densification during heat treatments.

  13. Analysis of frozen salt solutions with laser-induced breakdown spectroscopy under Martian conditions

    NASA Astrophysics Data System (ADS)

    Schröder, S.; Pavlov, S. G.; Hübers, H.-W.; Rauschenbach, I.; Jessberger, E. K.

    2010-05-01

    Laser-induced breakdown spectroscopy (LIBS) is a powerful analytical technique for determining the elemental composition of materials. It can be applied in-situ to geological surfaces on planetary missions. Since pure liquid water is unstable at the current surface conditions on Mars, i.e. low surface pressure and temperatures ranging from 140 K to 300 K, salt solutions or brines are of particular interest. It has been suggested that salts could stabilize liquid water on Mars lowering the freezing point of the solution and suppressing evaporation rates. The appropriate salts have been found on Mars in different locations. In this study LIBS is employed for the investigation of frozen sulphate and chloride solutions under Martian conditions in a dedicated simulation chamber. For the laboratory experiments, various salt solutions were prepared with different concentrations. To produce ice with only little inclusions of air, the samples were degassed before freezing them in a copper container. The measurements were performed at 240 K by cooling with liquid nitrogen and controlled heating. A constant flow of a Martian atmosphere-like gas mixture at a pressure of approximately 6 hPa was maintained through the chamber during the measurements. A Q-switched Nd:YAG laser operating at 1064nm and at 10 Hz was used to ablate material and to generate a plasma on the frozen sample's surface. The emitted light of the plasma was collected into the entrance slit of an echelle spectrometer (LTB Aryelle Butterfly) by a toroid mirror. A time-gated ICCD camera (Andor) at the exit of the spectrometer recorded the plasma emission signal. The laser beam was focused at a new position for each measurement. The delay time and the integration time of the spectrometer have been optimized to obtain good signal-to-noise ratios up to 150 while at the same time not losing signals from fast recombining ions. First, the spectra of several frozen salt solutions were investigated qualitatively

  14. Laser-induced breakdown spectroscopy for analysis of frozen salt solutions under Martian conditions

    NASA Astrophysics Data System (ADS)

    Schröder, Susanne; Pavlov, Sergey; Hübers, Heinz-Wilhelm; Rauschenbach, Isabelle; Jessberger, Elmar K.

    Laser-induced breakdown spectroscopy (LIBS) is a powerful analytical technique for determin-ing the elemental composition of materials. It can be applied in-situ to geological surfaces on planetary missions. Since pure liquid water is unstable at the current surface conditions on Mars, i.e. low surface pressure and temperatures ranging from 140 K to 300 K, salt solutions or brines are of particular interest. It has been suggested that salts could stabilize liquid water on Mars lowering the freezing point of the solution and suppressing evaporation rates. The ap-propriate salts have been found on Mars in different locations. In this study LIBS is employed for the investigation of frozen sulphate and chloride solutions under Martian conditions in a dedicated simulation chamber. For the laboratory experiments, various salt solutions were prepared with different concen-trations. To produce ice with only little inclusions of air, the samples were degassed before freezing them in a copper container. The measurements were performed at 240 K by cooling with liquid nitrogen and controlled heating. A constant flow of a Martian atmosphere-like gas mixture at a pressure of approximately 6 hPa was maintained through the chamber during the measurements. A Q-switched Nd:YAG laser operating at 1064nm and at 10 Hz was used to ablate material and to generate a plasma on the frozen sample's surface. The emitted light of the plasma was collected into the entrance slit of an echelle spectrometer (LTB Aryelle But-terfly) by a toroid mirror. A time-gated ICCD camera (Andor) at the exit of the spectrometer recorded the plasma emission signal. The laser beam was focused at a new position for each measurement. The delay time and the integration time of the spectrometer have been optimized to obtain good signal-to-noise ratios up to 150 while at the same time not losing signals from fast recombining ions. First, the spectra of several frozen salt solutions were investigated qualitatively

  15. Preliminary evaluation of solution-mining intrusion into a salt-dome repository

    SciTech Connect

    Not Available

    1981-06-01

    This report is the product of the work of an ONWI task force to evaluate inadvertant human intrusion into a salt dome repository by solution mining. It summarizes the work in the following areas: a general review of the levels of defense that could reduce both the likelihood and potential consequences of human intrusion into a salt dome repository; evaluation of a hypothetical intrusion scenario and its consequences; recommendation for further studies. The conclusions of this task force report can be summarized as follows: (1) it is not possible at present to establish with certainty that solution mining is credible as a human-intrusion event. The likelihood of such an intrusion will depend on the effectiveness of the preventive measures; (2) an example analysis based on the realistic approach is presented in this report; it concluded that the radiological consequences are strongly dependent upon the mode of radionuclide release from the waste form, time after emplacement, package design, impurities in the host salt, the amount of a repository intercepted, the solution mining cavity form, the length of time over which solution mining occurs, the proportion of contaminated salt source for human consumption compared to other sources, and the method of salt purification for culinary purposes; (3) worst case scenarios done by other studies suggest considerable potential for exposures to man while preliminary evaluations of more realistic cases suggest significantly reduced potential consequences. Mathematical model applications to process systems, guided by more advanced assumptions about human intrusion into geomedia, will shed more light on the potential for concerns and the degree to which mitigative measures will be required.

  16. Transferable ionic parameters for first-principles Poisson-Boltzmann solvation calculations: Neutral solutes in aqueous monovalent salt solutions

    NASA Astrophysics Data System (ADS)

    Ringe, Stefan; Oberhofer, Harald; Reuter, Karsten

    2017-04-01

    Implicit solvation calculations based on a Stern-layer corrected size-modified Poisson-Boltzmann (SMPB) model are an effective approach to capture electrolytic effects in first-principles electronic structure calculations. For a given salt solution, they require a range of ion-specific parameters, which describe the size of the dissolved ions as well as thickness and shape of the Stern layer. Out of this defined parameter space, we show that the Stern layer thickness expressed in terms of the solute's electron density and the resulting ionic cavity volume completely determine ion effects on the stability of neutral solutes. Using the efficient SMPB functionality of the full-potential density-functional theory package FHI-aims, we derive optimized such Stern layer parameters for neutral solutes in various aqueous monovalent electrolytes. The parametrization protocol relies on fitting to reference Setschenow coefficients that describe solvation free energy changes with ionic strength at low to medium concentrations. The availability of such data for NaCl solutions yields a highly predictive SMPB model that allows to recover the measured Setschenow coefficients with an accuracy that is comparable to prevalent quantitative regression models. Correspondingly derived SMPB parameters for other salts suffer from a much scarcer experimental data base but lead to Stern layer properties that follow a physically reasonable trend with ionic hydration numbers.

  17. Adsorption of N-alkylpyridinium chlorides from water and salt solutions on cellulose acetate ultrafiltration membranes

    SciTech Connect

    Klimenko, N.A.; Yaroshenko, N.A.; Kondratova, T.B.

    1988-09-01

    A study has been made of the adsorption of three homologues in the N-alkylpyridinium chloride series from water and salt solutions, over a wide range of concentrations, on cellulose acetate ultrafiltration membranes, Grades UAM-500 and UAM-150. When adsorption takes place from true solutions, the membrane surface is hydrophobized. In the region of micellar solutions, nonassociated molecules and micelles are adsorbed in the mesopores and supermicropores, forming a mosaic adsorption layer. The thickness of the modifying layer depends on the length of the hydrophobic radical and on the composition of the system.

  18. Nonmonotonic variation with salt concentration of the second virial coefficient in protein solutions.

    PubMed

    Allahyarov, E; Löwen, H; Hansen, J P; Louis, A A

    2003-05-01

    The osmotic virial coefficient B2 of globular protein solutions is calculated as a function of added salt concentration at fixed pH by computer simulations of the "primitive model." The salt and counterions as well as a discrete charge pattern on the protein surface are explicitly incorporated. For parameters roughly corresponding to lysozyme, we find that B2 first decreases with added salt concentration up to a threshold concentration, then increases to a maximum, and then decreases again upon further raising the ionic strength. Our studies demonstrate that the existence of a discrete charge pattern on the protein surface profoundly influences the effective interactions and that linear and nonlinear Poisson Boltzmann theories fail for large ionic strength. The observed nonmonotonicity of B2 is compared with experiments. Implications for protein crystallization are discussed.

  19. Molecular thermodynamics for swelling of a mesoscopic ionomer gel in 1 : 1 salt solutions.

    PubMed

    Victorov, A; Radke, C; Prausnitz, J

    2006-01-14

    For a microphase-separated diblock copolymer ionic gel swollen in salt solution, a molecular-thermodynamic model is based on the self-consistent field theory in the limit of strongly segregated copolymer subchains. The geometry of microdomains is described using the Milner generic wedge construction neglecting the packing frustration. A geometry-dependent generalized analytical solution for the linearized Poisson-Boltzmann equation is obtained. This generalized solution not only reduces to those known previously for planar, cylindrical and spherical geometries, but is also applicable to saddle-like structures. Thermodynamic functions are expressed analytically for gels of lamellar, bicontinuous, cylindrical and spherical morphologies. Molecules are characterized by chain composition, length, rigidity, degree of ionization, and by effective polymer-polymer and polymer-solvent interaction parameters. The model predicts equilibrium solvent uptakes and the equilibrium microdomain spacing for gels swollen in salt solutions. Results are given for details of the gel structure: distribution of mobile ions and polymer segments, and the electric potential across microdomains. Apart from effects obtained by coupling the classical Flory-Rehner theory with Donnan equilibria, viz. increased swelling with polyelectrolyte charge and shrinking of gel upon addition of salt, the model predicts the effects of microphase morphology on swelling.

  20. Intrinsic viscosity and conformational parameters of xanthan in aqueous solutions: salt addition effect.

    PubMed

    Brunchi, Cristina-Eliza; Morariu, Simona; Bercea, Maria

    2014-10-01

    The intrinsic viscosity and conformational parameters of xanthan in aqueous solutions were investigated at 25°C as a function of salt nature (NaCl and KCl) and concentration (up to 3×10(-1)mol/L). The viscometric parameters were evaluated by applying semi-empirical equations proposed by Rao and Wolf. The results show that the new model proposed by Wolf provides accurate intrinsic viscosity values comparable with those obtained by using traditional methods. The experimental data were modeled with Boltzmann sigmoidal equation. The stiffness parameter, hydrodynamic volume and viscometric expansion factor were determined and discussed. With increasing salt concentration, the hydrodynamic volume and the viscometric expansion factor decrease and the critical overlap concentration increases, reaching limiting values above a given salt concentration. The high Huggins constant values suggest the existence of aggregates for salt concentrations above 5×10(-2) and 3×10(-3)mol/L for NaCl and KCl, respectively. Stiffness parameter was determined by Smidsrød and Haug method as being 5.45×10(-3), indicating a rigid conformation for xanthan macromolecules in solution.

  1. Ultra-long-term human salt balance studies reveal interrelations between sodium, potassium, and chloride intake and excretion.

    PubMed

    Birukov, Anna; Rakova, Natalia; Lerchl, Kathrin; Engberink, Rik Hg Olde; Johannes, Bernd; Wabel, Peter; Moissl, Ulrich; Rauh, Manfred; Luft, Friedrich C; Titze, Jens

    2016-07-01

    The intake of sodium, chloride, and potassium is considered important to healthy nutrition and cardiovascular disease risk. Estimating the intake of these electrolytes is difficult and usually predicated on urine collections, commonly for 24 h, which are considered the gold standard. We reported on data earlier for sodium but not for potassium or chloride. We were able to test the value of 24-h urine collections in a unique, ultra-long-term balance study conducted during a simulated trip to Mars. Four healthy men were observed while ingesting 12 g salt/d, 9 g salt/d, and 6 g salt/d, while their potassium intake was maintained at 4 g/d for 105 d. Six healthy men were studied while ingesting 12 g salt/d, 9 g salt/d, and 6 g salt/d, with a re-exposure of 12 g/d, while their potassium intake was maintained at 4 g/d for 205 d. Food intake and other constituents were recorded every day for each subject. All urine output was collected daily. Long-term urine recovery rates for all 3 electrolytes were very high. Rather than the expected constant daily excretion related to daily intake, we observed remarkable daily variation in excretion, with a 7-d infradian rhythm at a relatively constant intake. We monitored 24-h aldosterone excretion in these studies and found that aldosterone appeared to be the regulator for all 3 electrolytes. We report Bland-Altman analyses on the value of urine collections to estimate intake. A single 24-h urine collection cannot predict sodium, potassium, or chloride intake; thus, multiple collections are necessary. This information is important when assessing electrolyte intake in individuals. © 2016 American Society for Nutrition.

  2. Ultra-long–term human salt balance studies reveal interrelations between sodium, potassium, and chloride intake and excretion12

    PubMed Central

    Birukov, Anna; Rakova, Natalia; Lerchl, Kathrin; Engberink, Rik HG Olde; Johannes, Bernd; Wabel, Peter; Moissl, Ulrich; Rauh, Manfred; Luft, Friedrich C; Titze, Jens

    2016-01-01

    Background: The intake of sodium, chloride, and potassium is considered important to healthy nutrition and cardiovascular disease risk. Estimating the intake of these electrolytes is difficult and usually predicated on urine collections, commonly for 24 h, which are considered the gold standard. We reported on data earlier for sodium but not for potassium or chloride. Objective: We were able to test the value of 24-h urine collections in a unique, ultra-long–term balance study conducted during a simulated trip to Mars. Design: Four healthy men were observed while ingesting 12 g salt/d, 9 g salt/d, and 6 g salt/d, while their potassium intake was maintained at 4 g/d for 105 d. Six healthy men were studied while ingesting 12 g salt/d, 9 g salt/d, and 6 g salt/d, with a re-exposure of 12 g/d, while their potassium intake was maintained at 4 g/d for 205 d. Food intake and other constituents were recorded every day for each subject. All urine output was collected daily. Results: Long-term urine recovery rates for all 3 electrolytes were very high. Rather than the expected constant daily excretion related to daily intake, we observed remarkable daily variation in excretion, with a 7-d infradian rhythm at a relatively constant intake. We monitored 24-h aldosterone excretion in these studies and found that aldosterone appeared to be the regulator for all 3 electrolytes. We report Bland–Altman analyses on the value of urine collections to estimate intake. Conclusions: A single 24-h urine collection cannot predict sodium, potassium, or chloride intake; thus, multiple collections are necessary. This information is important when assessing electrolyte intake in individuals. PMID:27225435

  3. Condensation of semiflexible polyelectrolytes in mixed solutions of mono- and multivalent salts

    NASA Astrophysics Data System (ADS)

    Plunk, Amelia A.; Luijten, Erik

    2013-03-01

    The salt-dependent condensation of highly charged polyelectrolytes in aqueous solution is a topic of great biological and industrial importance that has been widely studied over the past decades. It is well established that interaction with multivalent counterions leads to the formation of bundle-like aggregates for rigid polyelectrolytes and to collapsed structures or disordered aggregates for flexible polyelectrolytes. Here, we investigate the behavior of semiflexible chain molecules, where the electrostatically induced aggregation is impeded by the intrinsic bending stiffness of the polymer. Moreover, we study the competition between monovalent and multivalent counterions in mixed solutions and establish the threshold salt concentration required for condensation. Our findings are relevant for a range of biomedical problems, including the fabrication of nanoparticles for gene delivery and the packaging of DNA by histones. This work is supported by the National Science Foundation.

  4. Solution-derived sodalite made with Si- and Ge-ethoxide precursors for immobilizing electrorefiner salt

    SciTech Connect

    Riley, Brian J.; Lepry, William C.; Crum, Jarrod V.

    2016-01-01

    Chlorosodalite has the general form of Na8(AlSiO4)6Cl2 and this paper describes experiments conducted to synthesize sodalite to immobilize a mixed chloride salt using solution-based techniques. Sodalites were made using different Group IV contributions from either Si(OC2H5)4 or Ge(OC2H5)4, NaAlO2, and a simulated spent electrorefiner salt solution containing a mixture of alkali, alkaline earth, and lanthanide chlorides. Additionally, 6 glass binders at low loadings of 5 mass% were evaluated as sintering aids for the consolidation process. The approach of using the organic Group IV additives can be used to produce large quantities of sodalite at room temperature and shows promise over a method where colloidal silica is used as the silica source. However, the small particle sizes inhibited densification during pressure-less sintering.

  5. Characterization of Swollen States of Polyelectrolyte Brushes in Salt Solution by Neutron Reflectivity

    NASA Astrophysics Data System (ADS)

    Kobayashi, Motoyasu; Mitamura, Koji; Terada, Masami; Yamada, Norifumi L.; Takahara, Atsushi

    2011-01-01

    Cationic and zwitterionic polyelectrolyte brushes on quartz substrate were synthesized by surface-initiated atom transfer radical polymerization of 2-(methacryloyloxy)-ethyltrimethylammonium chloride (MTAC) and 2-(methacryloyloxy)ethyl phosphorylcholine (MPC). The effects of ionic strength on brush structure are investigated by neutron reflectivity (NR) in NaCl deuterium oxide (D2O) solutions. We observed that poly(MTAC) chains were drastically shrunk at concentrations above 0.1 M NaCl/D2O, which may be the change in charge-screening effect against ions on poly(MTAC). On the other hand, effect of salt concentration on a swollen state of poly(MPC) brush was negligible, even at the high concentration (5.0 M) close to saturation. The behaviour of poly(MPC) in salt aqueous solution is completely different from that of poly(MTAC), which may arise from the unique interaction properties, neutral nature, and hydrated water structure of phosphorylcholine units.

  6. Characterization of swollen structure of high-density polyelectrolyte brushes in salt solution by neutron reflectivity

    NASA Astrophysics Data System (ADS)

    Kobayashi, Motoyasu; Terayama, Yuki; Hino, Masahiro; Ishihara, Kazuhiko; Takahara, Atsushi

    2009-08-01

    Zwitterionic and cationic polyelectrolyte brushes on quartz substrate were prepared by surface-initiated atom transfer radical polymerization of 2-(methacryloyloxy)ethyl phosphorylcholine (MPC) and 2-(methacryloyloxy)ethyltrimethylammonium chloride (METAC), respectively. The effects of ionic strength on brush structure and surface properties of densely grafted polyelectrolyte brushes were analysed by neutron reflectivity (NR) measurements. NR at poly(METAC)/D2O and poly(MPC)/D2O interface revealed that the grafted polymer chains were fairly extended from the substrate surface, while the thickness reduction of poly(METAC) brush was observed in 5.6 M NaCl/D2O solution due to the screening of the repulsive interaction between polycations by hydrated salt ions. Interestingly, no structural change was observed in poly(MPC) brush even in a salt solution probably due to the unique interaction properties of phosphorylcholine units.

  7. Prediction of subsidence resulting from creep closure of solutioned-mined caverns in salt domes

    SciTech Connect

    Neal, J.T.

    1991-01-01

    The prediction of subsidence rates over a range of areal configurations of solution-mined caverns in salt domes is possible, based on some fifty years of history in solution mining. Several approaches contribute to predictions: site-specific observations obtained from subsidence monitoring; numerical modeling, now becoming more practicable and credible; salt-creep data from testing; and rule-of-thumb methods, based on experience. All of these approaches contribute to understanding subsidence but none are totally reliable alone. The example of subsidence occurring at the Strategic Petroleum Reserve sites demonstrates several principles of cavern creep closure, the main cause of the subsidence, and shows that reliable projections of future subsidence are possible. 13 refs., 6 figs.

  8. Impact of co-digestion on existing salt and nutrient mass balances for a full-scale dairy energy project.

    PubMed

    Camarillo, Mary Kay; Stringfellow, William T; Spier, Chelsea L; Hanlon, Jeremy S; Domen, Jeremy K

    2013-10-15

    Anaerobic digestion of manure and other agricultural waste streams with subsequent energy production can result in more sustainable dairy operations; however, importation of digester feedstocks onto dairy farms alters previously established carbon, nutrient, and salinity mass balances. Salt and nutrient mass balance must be maintained to avoid groundwater contamination and salination. To better understand salt and nutrient contributions of imported methane-producing substrates, a mass balance for a full-scale dairy biomass energy project was developed for solids, carbon, nitrogen, sulfur, phosphorus, chloride, and potassium. Digester feedstocks, consisting of thickened manure flush-water slurry, screened manure solids, sudan grass silage, and feed-waste, were tracked separately in the mass balance. The error in mass balance closure for most elements was less than 5%. Manure contributed 69.2% of influent dry matter while contributing 77.7% of nitrogen, 90.9% of sulfur, and 73.4% of phosphorus. Sudan grass silage contributed high quantities of chloride and potassium, 33.3% and 43.4%, respectively, relative to the dry matter contribution of 22.3%. Five potential off-site co-digestates (egg waste, grape pomace, milk waste, pasta waste, whey wastewater) were evaluated for anaerobic digestion based on salt and nutrient content in addition to bio-methane potential. Egg waste and wine grape pomace appeared the most promising co-digestates due to their high methane potentials relative to bulk volume. Increasing power production from the current rate of 369 kW to the design value of 710 kW would require co-digestion with either 26800 L d(-1) egg waste or 60900 kg d(-1) grape pomace. However, importation of egg waste would more than double nitrogen loading, resulting in an increase of 172% above the baseline while co-digestion with grape pomace would increase potassium by 279%. Careful selection of imported co-digestates and management of digester effluent is required to

  9. Water balance and N-metabolism in broccoli (Brassica oleracea L. var. Italica) plants depending on nitrogen source under salt stress and elevated CO2.

    PubMed

    Zaghdoud, Chokri; Carvajal, Micaela; Ferchichi, Ali; Del Carmen Martínez-Ballesta, María

    2016-11-15

    Elevated [CO2] and salinity in the soils are considered part of the effects of future environmental conditions in arid and semi-arid areas. While it is known that soil salinization decreases plant growth, an increased atmospheric [CO2] may ameliorate the negative effects of salt stress. However, there is a lack of information about the form in which inorganic nitrogen source may influence plant performance under both conditions. Single factor responses and the interactive effects of two [CO2] (380 and 800ppm), three different NO3(-)/NH4(+) ratios in the nutrient solution (100/0, 50/50 and 0/100, with a total N concentration of 3.5mM) and two NaCl concentrations (0 and 80mM) on growth, leaf gas exchange parameters in relation to root hydraulic conductance and N-assimilating enzymes of broccoli (Brassica oleracea L. var. Italica) plants were determined. The results showed that a reduced NO3(-) or co-provision of NO3(-) and NH4(+) could be an optimal source of inorganic N for broccoli plants. In addition, elevated [CO2] ameliorated the effect of salt exposure on the plant growth through an enhanced rate of photosynthesis, even at low N-concentration. However, NO3(-) or NO3(-)/NH4(+) co-provision display differential plant response to salt stress regarding water balance, which was associated to N metabolism. The results may contribute to our understanding of N-fertilization modes under increasing atmospheric [CO2] to cope with salt stress, where variations in N nutrition significantly influenced plant response.

  10. Studies of 6Li-NMR properties in different salt solutions in low magnetic fields

    NASA Astrophysics Data System (ADS)

    Gordji-Nejad, A.; Colell, J.; Glöggler, S.; Blümich, B.; Appelt, S.

    2012-01-01

    In this article we report the longitudinal relaxation times ( T1) of various 6Li salts ( 6LiI, 6LiCl and 6LiNO 3) in D 2O and H 2O, measured in low magnetic fields ( B0 = 3.5 mT). This investigation serves the purpose of clarifying the relaxation behavior of different 6Li solutions and different concentrations. The measurement were undertaken to establish a framework for future applications of hyperpolarized 6Li in medical imaging, biological studies and investigations of lithium ion batteries. Time will pass during the transport of hyperpolarized lithium ions to the sample, which leads to a polarization loss. In order to store polarization as long as possible, it is necessary to examine which 6Li salt solution has the longest relaxation time T1. Longitudinal relaxation times of 6Li salts in D 2O and H 2O were investigated as a function of concentration and the most extended T1 was found for 6LiI in D 2O and H 2O. In agreement with the theory the relaxation time T1 of all 6Li salts increase with decreasing concentration. In the case of 6LiI in H 2O an inverse behavior was observed. We assume that the prolonged T1 times occur due to formation of 6LiOH upon the solution of 6LiI in H 2O, which settles as a precipitate. By diluting the solution, the precipitate continuously dissolves and approaches T1 of 6LiOH ( T1 ˜ 28 s), leading to a shorter T1 relaxation time.

  11. External application of hypertonic salt solution for treatment of posttraumatic oedema.

    PubMed

    Atalar, Hakan; Yavuz, Osman Y; Uras, Ismail; Selek, Hakan; Erakar, Aziz; Sayli, Ugur

    2005-08-01

    In 20 New Zealand rabbits (two groups of 10 rabbits each), hind limb circumference and anterior compartment pressure were measured following ketamin anaesthesia (time zero). During the same anaesthesia, closed transverse proximal tibial shaft fractures were created in both groups. Twenty-four hours after the fractures, during a second anaesthesia, limb circumference and compartment pressure were measured as before, and fractured limbs were fixed to the rabbits' bodies. At the same time, treatment was started: one group received external application of saturated salt solution and the other group received intermittent ice application. During 48 hours of treatment (from 24 to 72 hours) in the saturated salt solution group, the mean limb circumference decreased from 125.70 +/- 9.93 mm to 115.70 +/- 8.78 mm (p = 0.005) and the mean compartment pressure decreased from 18.30 +/- 1.70 mmHg to 12.40 +/- 1.77 mmHg (p = 0.005). In the control group, the mean limb circumference decreased from 127.85 +/- 7.47 mm to 122.00 +/- 6.83 mm (not significant) and the mean compartment pressure decreased from 19.57 +/- 1.27 mmHg to 17.85 +/- 2.67 mmHg (not significant). In short, differences in compartment pressure and limb circumference before and after treatment were statistically significant in the saturated salt solution group (p = 0.005) but not in the control group.

  12. Investigation of the salting out of methane from aqueous electrolyte solutions using computer simulations.

    PubMed

    Docherty, H; Galindo, A; Sanz, E; Vega, C

    2007-08-02

    We calculate the excess chemical potential of methane in aqueous electrolyte solutions of NaCl using Monte Carlo computer simulations. In a recent work [Docherty et al. J. Chem. Phys. 2006, 125, 074510], we presented a new potential model for methane in water which is capable of describing accurately the excess chemical potential of methane in pure water over a range of temperatures, a quantity that can be related to the solubility and which is commonly used to study the hydrophobic effect. Here, we use the same potential model for the water-methane interactions and investigate the effect of added salt on the chemical potential of methane in the solution. The methane molecules are modeled as single Lennard-Jones (LJ) interaction sites, and the water molecules are modeled with the TIP4P/2005 model. A correcting factor of chi = 1.07 for the energetic Berthelot (geometric) combining rule of the methane-water interaction is also used, which mimics the polarization of methane in water. We consider NaCl as the salt and treat the ions with the Smith and Dang model (i.e., as charged LJ interaction sites). Ion-water, ion-ion, and ion-methane interactions are treated using Lorentz-Berthelot combining rules. In addition, the Coulombic potential is used to model charge-charge interactions which are calculated using the Ewald sum. We have carried out isobaric-isothermal (NpT) simulations to determine the equilibrium densities of the solutions. The simulation data is in excellent agreement with experimental densities of aqueous NaCl solutions of different concentration. Hydration numbers are also obtained and found to be in agreement with reported data. Canonical (NVT) simulations at the averaged densities are then performed using the Widom test-particle insertion method to obtain the excess chemical potential of methane in the saline solutions. An increase in the chemical potential of methane, corresponding to a salting out effect, is observed when salt is added to the solution

  13. Precision and accuracy of TearLab osmometer in measuring osmolarity of salt solutions.

    PubMed

    Yoon, Dan; Gadaria-Rathod, Neha; Oh, Cheongeun; Asbell, Penny A

    2014-12-01

    The purpose of this study was to examine the inherent precision and accuracy of TearLab Osmolarity System using salt solutions, including solutions of very high osmolarity (>360 mOsm/L). Ten salt solutions with osmolarity between 286 mOsm/L and 394 mOsm/L (increments of 12 mOsm/L) plus an additional solution of 400 mOsm/L were tested twice on both the TearLab osmometer and a freezing point depression osmometer. For precision, we compared the two repeated osmolarity measurements of 11 solutions obtained from TearLab. For accuracy, we compared the averaged osmolarity measurements obtained from TearLab to those from the freezing point depression osmometer. For both precision and accuracy, Bland-Altman test of agreement was used. For precision, the upper 95% limit of agreement was 4.7 mOsm/L, and the lower 95% limit of agreement was -7.1 mOsm/L. The repeatability coefficient was 5.9 mOsm/L. For accuracy, the upper 95% limit of agreement was 4.8 mOsm/L and the lower 95% limit of agreement was -5.3 mOsm/L. The present study is the first study to demonstrate that the TearLab in situ osmometer can precisely and accurately measure osmolarity of salt solutions, including those with very high osmolarity. Future studies to evaluate the precision and the accuracy of the machine in measuring complex fluids, such as tears, need to be done, and the clinical significance of measuring tear osmolarity in patients needs to be further determined.

  14. Inefficacy of osmotic backwash induced by sodium chloride salt solution in controlling SWRO membrane fouling

    NASA Astrophysics Data System (ADS)

    Farooque, A. Mohammed; Al-Jeshi, Subhi; Saeed, Mohamed O.; Alreweli, Ali

    2014-12-01

    A study was conducted to evaluate the efficacy of osmotic backwash induced by high salt (NaCl) concentration solution on feed side of seawater reverse osmosis (SWRO) membranes, online and offline, in controlling membrane fouling and therefore minimizing/eliminating the need for chemical cleaning. SWRO membranes were deliberately fouled by feeding seawater from an open intake located on the Arabian Gulf Coast without dosing chemicals. The fouled membranes were subjected to offline cleaning with the salt solution of up to 25 % concentration. Despite the partial removal of foulants from the membrane surface, SWRO membrane performance could not be restored, indicating the ineffectiveness of osmotic backwash in aiding offline salt cleaning. Similarly, online osmotic backwash was found to be not only ineffective in removing foulants from membrane surfaces but actually increased the fouling rate, as indicated by faster fouling rates compared to other cases. Although the driving force required for the osmotic backwash existed, the generated back flow proved to be insufficient to detach foulants from membrane surfaces. During the study period, the average SWRO membrane flux was maintained between 19 and 23 LMH, whereas the average generated back flow flux by high salt concentration solution was only 11 LMH, which was not adequate to remove foulants from membrane surfaces. Moreover, it seems that the membrane configuration as well as inherent microstructure of SWRO membrane places certain constraints on the osmotic backwash process and renders osmotic backwash ineffective in tackling SWRO membrane fouling. Hence, chemical cleaning is essential to restore SWRO membrane performance whenever fouling occurs, and the use of highly concentrated salt solution does not have any significant benefit. Membrane autopsy revealed only an insignificant accumulation of biofouling layer despite the absence of disinfection. However, it was shown that culturable biofilm bacteria species

  15. An empirical correlation between the enthalpy of solution of aqueous salts and their ability to form hydrates

    SciTech Connect

    Pandelov, S.; Werhahn, Jasper C.; Pilles, Bert M.; Xantheas, Sotiris S.; Iglev, H.

    2010-09-30

    The ability of aqueous salt solutions to form hydrates by cooling them at ambient pressure is probed by infrared (IR) spectroscopy by examining the structure of the spectra in the hydrogen-bonding region (3,000 - 3,800 cm-1). A collection of 75 organic and inorganic salts in saturated solutions are examined. We have found a correlation between the enthalpy of solution of the salt and its ability to form a hydrate, namely that the salt’s enthalpy of solution is lower than the standard enthalpy of fusion of ice (6 kJ/mol). This observation can serve as an empirical rule that determines whether a salt will form a hydrate upon cooling from its aqueous solution.

  16. Ice crystallization in ultrafine water-salt aerosols: nucleation, ice-solution equilibrium, and internal structure.

    PubMed

    Hudait, Arpa; Molinero, Valeria

    2014-06-04

    Atmospheric aerosols have a strong influence on Earth's climate. Elucidating the physical state and internal structure of atmospheric aqueous aerosols is essential to predict their gas and water uptake, and the locus and rate of atmospherically important heterogeneous reactions. Ultrafine aerosols with sizes between 3 and 15 nm have been detected in large numbers in the troposphere and tropopause. Nanoscopic aerosols arising from bubble bursting of natural and artificial seawater have been identified in laboratory and field experiments. The internal structure and phase state of these aerosols, however, cannot yet be determined in experiments. Here we use molecular simulations to investigate the phase behavior and internal structure of liquid, vitrified, and crystallized water-salt ultrafine aerosols with radii from 2.5 to 9.5 nm and with up to 10% moles of ions. We find that both ice crystallization and vitrification of the nanodroplets lead to demixing of pure water from the solutions. Vitrification of aqueous nanodroplets yields nanodomains of pure low-density amorphous ice in coexistence with vitrified solute rich aqueous glass. The melting temperature of ice in the aerosols decreases monotonically with an increase of solute fraction and decrease of radius. The simulations reveal that nucleation of ice occurs homogeneously at the subsurface of the water-salt nanoparticles. Subsequent ice growth yields phase-segregated, internally mixed, aerosols with two phases in equilibrium: a concentrated water-salt amorphous mixture and a spherical cap-like ice nanophase. The surface of the crystallized aerosols is heterogeneous, with ice and solution exposed to the vapor. Free energy calculations indicate that as the concentration of salt in the particles, the advance of the crystallization, or the size of the particles increase, the stability of the spherical cap structure increases with respect to the alternative structure in which a core of ice is fully surrounded by

  17. Spectrophotometric investigation of reaction of uranyl salts with neutral organophosphorus compounds in aqueous solutions

    SciTech Connect

    Takshin, V.V.; Khokhlova, N.L.

    1985-07-01

    The authors study the reaction of uranyl salts with neutral organophosphorous compounds in aqueous solutions of mineral acids. They show that compounds of the R /SUB n/ P(O)-(OR) /SUB 3-n/ type (n = 0, 1, 2, 3; R = CH/sub 3/, C/sub 2/H/sub 5/) do not form complexes with UO/sub 2//sup 2 +/. In perchlorate solutions U/sub 2//sup 2 +/ forms complex with ((CH/sub 3/)/sub 2/ N)/sub 3/ PO. The equilibrium constant of this reaction is 6.4 + or - 0.6 mole/sup -1/. liter at 298 degrees K.

  18. Aqueous Biphasic Systems Based on Salting-Out Polyethylene Glycol or Ionic Solutions: Strategies for Actinide or Fission Product Separations

    SciTech Connect

    Rogers, Robin D.; Gutowski, Keith E.; Griffin, Scott T.; Holbrey, John D.

    2004-03-29

    Aqueous biphasic systems can be formed by salting-out (with kosmotropic, waterstructuring salts) water soluble polymers (e.g., polyethylene glycol) or aqueous solutions of a wide range of hydrophilic ionic liquids based on imidazolium, pyridinium, phosphonium and ammonium cations. The use of these novel liquid/liquid biphases for separation of actinides or other fission products associated with nuclear wastes (e.g., pertechnetate salts) has been demonstrated and will be described in this presentation.

  19. Rheological properties and thickening mechanism of aqueous diutan gum solution: Effects of temperature and salts.

    PubMed

    Xu, Long; Gong, Houjian; Dong, Mingzhe; Li, Yajun

    2015-11-05

    Rheological properties of a new microbial polysaccharide, diutan gum in aqueous solution have been systematically investigated. It is found that molecular aggregates of diutan gum can be formed at a very low concentration (0.12 g/L), and the mechanism of thickening by diutan gum is proposed. The viscosity retention rate of diutan gum changes little when increasing the temperature from 298 K to 348 K or in a high salinity solution (55.5 g L(-1)). Gel structure can be formed in the diutan gum solution, owing to the finding that the dynamic modulus has an exponential relationship with the concentration. The gel properties of diutan gum are not sensitive to temperature, and are virtually independent of cationic environment (Na(+) and Ca(2+)). The temperature/salt tolerance of the diutan gum solution is mainly attributed to its perfect double helix molecular conformation, the location of the side chains of its molecules, and its water retention capacity.

  20. Multicentre evaluation of reduced-osmolarity oral rehydration salts solution. International Study Group on Reduced-osmolarity ORS solutions.

    PubMed

    1995-02-04

    In developed countries, use of oral rehydration salts (ORS) solution with osmolarity lower than that of plasma has been recommended because of the risk of hypernatraemia. We compared the clinical efficacy of reduced-osmolarity ORS and standard ORS solutions in children with acute diarrhoea in four developing countries. 447 boys aged 1-24 months, admitted to hospitals in four countries with acute diarrhoea and signs of dehydration, were randomly assigned either standard ORS (311 mmol/L) or reduced-osmolarity ORS (224 mmol/L) solution. Total stool output was 39% greater (95% CI 11-75), total ORS intake 18% greater (3-33), and duration of diarrhoea 22% longer (2-45) in the standard ORS group than in the reduced-osmolarity ORS group. The risk of requiring intravenous infusion after completion of the initial oral rehydration was greater in children given standard ORS solution than in those given reduced-osmolarity ORS solution in three of the four countries (all-country relative risk 1.4 [0.9-2.4]). This relative risk was significantly increased only in non-breastfed children (2.0 [1.0-3.8], p < 0.05). In breastfed children, the relative risk of requiring intravenous infusion was not affected by the ORS solution (0.9 [0.4-2.0]). The mean sodium concentration 24 h after admission was significantly lower in the reduced-osmolarity ORS group than in the standard ORS group (135 [134-136] vs 138 [136-139] mmol/L, p < 0.01). Reduced-osmolarity ORS solution has beneficial effects on the clinical course of acute diarrhoea. Our findings support the use of reduced-osmolarity ORS solution in children with acute non-cholera diarrhoea in developing countries. Further studies are needed to find the best formulation and whether such a solution would be satisfactory for the treatment of cholera.

  1. Adding salt to a surfactant solution: Linear rheological response of the resulting morphologies

    SciTech Connect

    Gaudino, Danila; Pasquino, Rossana Grizzuti, Nino

    2015-11-15

    The micellar system composed of Cetylpyridinium Chloride-Sodium Salicylate (CPyCl-NaSal) in brine aqueous solutions has been studied by systematically changing the salt concentration, in order to investigate the rheology of the arising morphologies. In particular, the zero-shear viscosity and the linear viscoelastic response have been measured as a function of the NaSal concentration (with [CPyCl] = 100 mM). The Newtonian viscosity shows a nonmonotonic dependence upon concentration, passing through a maximum at NaSal/CPyCl ≈ 0.6, and eventually dropping at higher salt concentrations. The progressive addition of salt determines first a transition from a Newtonian to a purely Maxwell-like behavior as the length of the micelles significantly increases. Beyond the peak viscosity, the viscoelastic data show two distinct features. On the one hand, the main relaxation time of the system strongly decreases, while the plateau modulus remains essentially constant. Calculations based on the rheological data show that, as the binding salt concentration increases, there is a decrease in micelles breaking rate and a decrease in their average length. On the other hand, in the same concentration region, a low-frequency elastic plateau is measured. Such a plateau is considered as the signature of a tenuous, but persistent branched network, whose existence is confirmed by cryo-transmission electron microscopy images.

  2. Absorption and desorption of SO2 in aqueous solutions of diamine-based molten salts.

    PubMed

    Lim, Seung Rok; Hwang, Junhyeok; Kim, Chang Soo; Park, Ho Seok; Cheong, Minserk; Kim, Hoon Sik; Lee, Hyunjoo

    2015-05-30

    SO2 absorption and desorption behaviors were investigated in aqueous solutions of diamine-derived molten salts with a tertiary amine group on the cation and a chloride anion, including butyl-(2-dimethylaminoethyl)-dimethylammonium chloride ([BTMEDA]Cl, pKb=8.2), 1-butyl-1,4-dimethylpiperazinium chloride ([BDMP]Cl, pKb=9.8), and 1-butyl-4-aza-1-azoniabicyclo[2,2,2]octane chloride ([BDABCO]Cl, pKb=11.1). The SO2 absorption and desorption performance of the molten salt were greatly affected by the basicity of the molten salt. Spectroscopic, X-ray crystallographic, and computational results for the interactions of SO2 with molten salts suggest that two types of SO2-containg species could be generated depending on the basicity of the unquaternized amino group: a dicationic species comprising two different anions, HSO3(-) and Cl(-), and a monocationic species bearing Cl(-) interacting with neutral H2SO3. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Analytical Results from Salt Solution Feed Tank (SSFT) Samples HTF-16-6 and HTF-16-40

    SciTech Connect

    Peters, T.

    2016-09-23

    Two samples from the Salt Solution Feed Tank (SSFT) were analyzed by SRNL, HTF-16-6 and HTF-16-40. Multiple analyses of these samples indicate a general composition almost identical to that of the Salt Batch 8-B feed and the Tank 21H sample results.

  4. Molecular Thermodynamics for Swelling of a Mesoscopic Ionomer Gelin 1:1 Salt Solutions

    SciTech Connect

    Victorov, Alexey; Radke, Clayton; Prausnitz,John

    2005-06-15

    For a microphase-separated diblock copolymer ionic gel swollen in salt solution, a molecular-thermodynamic model is based on the self-consistent field theory in the limit of strongly segregated copolymer subchains. The geometry of microdomains is described using the Milner generic wedge construction neglecting the packing frustration. Thermodynamic functions are expressed analytically for gels of lamellar, bicontinuous, cylindrical and spherical morphologies. Molecules are characterized by chain composition, length, rigidity, degree of ionization, and by effective polymer-polymer and polymer-solvent interaction parameters. The model predicts equilibrium solvent uptakes and the equilibrium microdomain spacing for gels swollen in salt solutions. Results are given for details of the gel structure: distribution of mobile ions and polymer segments, and the electric potential across microdomains. Apart from effects obtained by coupling classical Flory-Rehner theory with Donnan equilibria, viz., increased swelling with polyelectrolyte charge and shrinking of gel upon addition of salt, the model predicts the effects of microphase morphology on swelling.

  5. Enhanced copper surface protection in aqueous solutions containing short-chain alkanoic acid potassium salts.

    PubMed

    Abelev, Esta; Starosvetsky, David; Ein-Eli, Yair

    2007-10-23

    The ability of dissolved potassium monocarboxylate salts to produce surface passivation and to inhibit aqueous corrosion of copper was studied. The electrochemical measurements indicate that the inhibiting efficiency of these compounds, with a general formula Cn-1H2n-1COOK or CnK (n=3...12), is dependent on the hydrocarbon chain length. The inhibiting efficiency was higher for a longer hydrocarbon chain of n-alkanoic acid. The degree of copper protection was found to increase with an increase in n-alkanoic acid potassium salt concentration; the optimum concentration of potassium dodecanoate (C12K) in sulfate solutions was found to be 0.07 M. The protective layers formed at the copper surface subsequent to exposure in various n-alkanoic acid potassium salt solutions were characterized by contact angle measurements, electrochemical impedance spectroscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared reflection spectroscopy. Pronounced copper protection was attributed to the growth of a protective film on the copper surface, containing both copper oxides and copper carboxylate compounds. It is suggested that the organic molecules enhance copper protection by covering copper oxides with a thin and dense organic layer, which prevents water molecules or aggressive anions from interacting with the copper surface.

  6. Viscosity-Reducing Bulky-Salt Excipients Prevent Gelation of Protein, but Not Carbohydrate, Solutions.

    PubMed

    Kumar, Awanish; Klibanov, Alexander M

    2017-08-01

    The problem of gelation of concentrated protein solutions, which poses challenges for both downstream protein processing and liquid formulations of pharmaceutical proteins, is addressed herein by employing previously discovered viscosity-lowering bulky salts. Procainamide-HCl and the salt of camphor-10-sulfonic acid with L-arginine (CSA-Arg) greatly retard gelation upon heating and subsequent cooling of the model proteins gelatin and casein in water: Whereas in the absence of additives the proteins form aqueous gels within several hours at room temperature, procainamide-HCl for both proteins and also CSA-Arg for casein prevent gel formation for months under the same conditions. The inhibition of gelation by CSA-Arg stems exclusively from the CSA moiety: CSA-Na was as effective as CSA-Arg, while Arg-HCl was marginally or not effective. The tested bulky salts did not inhibit (and indeed accelerated) temperature-induced gel formation in aqueous solutions of all examined carbohydrates-starch, agarose, alginate, gellan gum, and carrageenan.

  7. Effects of Detergent β-Octylglucoside and Phosphate Salt Solutions on Phase Behavior of Monoolein Mesophases

    PubMed Central

    Khvostichenko, Daria S.; Ng, Johnathan J.D.; Perry, Sarah L.; Menon, Monisha; Kenis, Paul J.A.

    2013-01-01

    Using small-angle x-ray scattering (SAXS), we investigated the phase behavior of mesophases of monoolein (MO) mixed with additives commonly used for the crystallization of membrane proteins from lipidic mesophases. In particular, we examined the effect of sodium and potassium phosphate salts and the detergent β-octylglucoside (βOG) over a wide range of compositions relevant for the crystallization of membrane proteins in lipidic mesophases. We studied two types of systems: 1), ternary mixtures of MO with salt solutions above the hydration boundary; and 2), quaternary mixtures of MO with βOG and salt solutions over a wide range of hydration conditions. All quaternary mixtures showed highly regular lyotropic phase behavior with the same sequence of phases (Lα, Ia3d, and Pn3m) as MO/water mixtures at similar temperatures. The effects of additives in quaternary systems agreed qualitatively with those found in ternary mixtures in which only one additive is present. However, quantitative differences in the effects of additives on the lattice parameters of fully hydrated mesophases were found between ternary and quaternary mixtures. We discuss the implications of these findings for mechanistic investigations of membrane protein crystallization in lipidic mesophases and for studies of the suitability of precipitants for mesophase-based crystallization methods. PMID:24138861

  8. Periodic wave solutions of coupled integrable dispersionless equations by residue harmonic balance

    NASA Astrophysics Data System (ADS)

    Leung, A. Y. T.; Yang, H. X.; Guo, Z. J.

    2012-11-01

    We introduce the residue harmonic balance method to generate periodic solutions for nonlinear evolution equations. A PDE is firstly transformed into an associated ODE by a wave transformation. The higher-order approximations to the angular frequency and periodic solution of the ODE are obtained analytically. To improve the accuracy of approximate solutions, the unbalanced residues appearing in harmonic balance procedure are iteratively considered by introducing an order parameter to keep track of the various orders of approximations and by solving linear equations. Finally, the periodic solutions of PDEs result. The proposed method has the advantage that the periodic solutions are represented by Fourier functions rather than the sophisticated implicit functions as appearing in most methods.

  9. Molecular dynamics study of salt–solution interface: Solubility and surface charge of salt in water

    SciTech Connect

    Kobayashi, Kazuya; Liang, Yunfeng E-mail: matsuoka@earth.kumst.kyoto-u.ac.jp; Matsuoka, Toshifumi E-mail: matsuoka@earth.kumst.kyoto-u.ac.jp; Sakka, Tetsuo

    2014-04-14

    The NaCl salt–solution interface often serves as an example of an uncharged surface. However, recent laser-Doppler electrophoresis has shown some evidence that the NaCl crystal is positively charged in its saturated solution. Using molecular dynamics (MD) simulations, we have investigated the NaCl salt–solution interface system, and calculated the solubility of the salt using the direct method and free energy calculations, which are kinetic and thermodynamic approaches, respectively. The direct method calculation uses a salt–solution combined system. When the system is equilibrated, the concentration in the solution area is the solubility. In the free energy calculation, we separately calculate the chemical potential of NaCl in two systems, the solid and the solution, using thermodynamic integration with MD simulations. When the chemical potential of NaCl in the solution phase is equal to the chemical potential of the solid phase, the concentration of the solution system is the solubility. The advantage of using two different methods is that the computational methods can be mutually verified. We found that a relatively good estimate of the solubility of the system can be obtained through comparison of the two methods. Furthermore, we found using microsecond time-scale MD simulations that the positively charged NaCl surface was induced by a combination of a sodium-rich surface and the orientation of the interfacial water molecules.

  10. Centrifugal separation for miscible solutions: Fundamentals and applications to separation of molten salt nuclear material

    SciTech Connect

    Ning Li; Camassa, R.; Ecke, R.E.

    1995-10-01

    The authors report on the physical separation of dilute solutions using centrifugal techniques. They use numerical simulations of the diffusion and sedimentation dynamics of centrifugation to model the approach to an equilibrium concentration profile. They verify experimentally the equilibrium profiles for aqueous solutions of different salts under rotation at 25000 rpm corresponding to centrifugal accelerations of about 57,000 g and 75,000 g in two different commercial centrifuges. These measurements provide ratios of sedimentation and diffusion coefficients. The authors show experimental results for the dynamics of separation that confirm the predictions of the theoretical model. They also measure the mass diffusion coefficient for several solutions. Although the relaxation to equilibrium is long, they have determined a method for efficiently extracting enriched components from a ternary mixture based on fast dynamics at early times. These dynamics are modeled in numerical simulations with realistic fluid parameters. Based on these studies the authors show that a multistage centrifugal separation process could provide efficient physical separation of actinides and fission products from a molten-salt solution in proposed transmutation/energy-production systems. The authors consider technical issues in the design of such a separation system.

  11. Coarse-grained model of glycosaminoglycans in aqueous salt solutions. A field-theoretical approach.

    PubMed

    Kolesnikov, Andrei L; Budkov, Yurij A; Nogovitsyn, Evgenij A

    2014-11-20

    We present results of self-consistent field calculations of thermodynamic and structural properties of glycosaminoglycans (chondroitin sulfate, hyaluronic acid, and heparin) in aqueous solutions with added monovalent and divalent salts. A semiphenomenological coarse-grained model for semiflexible polyelectrolyte chains in solution is proposed. The coarse-grained model permits one to focus on the essential features of these systems and provides significant computational advantages with respect to more detailed models. Our approach relies on the method of Gaussian equivalent representation for the calculation of the partition functions in the form of functional integrals. This method provides reliable thermodynamic information for polyelectrolyte solutions over wide ranges of monomer concentrations. In the present work, we use the comparison and fitting of the experimental osmotic pressure with a theoretical equation of state within the Gaussian equivalent representation. The degrees of ionization, radii of gyration, persistence lengths, and structure factors of chondroitin sulfate, hyaluronic acid, and heparin in aqueous solutions with added monovalent and divalent salts are calculated and discussed.

  12. BALANCE

    DOEpatents

    Carmichael, H.

    1953-01-01

    A torsional-type analytical balance designed to arrive at its equilibrium point more quickly than previous balances is described. In order to prevent external heat sources creating air currents inside the balance casing that would reiard the attainment of equilibrium conditions, a relatively thick casing shaped as an inverted U is placed over the load support arms and the balance beam. This casing is of a metal of good thernnal conductivity characteristics, such as copper or aluminum, in order that heat applied to one portion of the balance is quickly conducted to all other sensitive areas, thus effectively preventing the fornnation of air currents caused by unequal heating of the balance.

  13. Application of a bubble column for evaporative cooling and a simple procedure for determining the latent heat of vaporization of aqueous salt solutions.

    PubMed

    Francis, M J; Pashley, R M

    2009-07-09

    In this work we have studied the evaporative cooling effect produced in a continuous flow air bubble column, containing water and salt solutions. We have established that, at equilibrium, a significant reduction in temperature is produced in an insulated, continuous flow, bubble column. For example, with a continuous flow of inlet air at 22 degrees C, a water bubble column cools to about 8 degrees C, at steady state equilibrium. The cooling effect observed in a continuous bubble column of concentrated aqueous salt solution could be used for commercial applications, such as for evaporative cooling systems. We have developed a simple method, based on the steady state thermal energy balance developed in a bubble column, to determine the latent heat of vaporization of the liquid in the column. Only the equilibrium temperature of the bubble column, the temperature of the inlet gas and the hydrostatic pressure across the column need to be measured. This analysis has been used to determine the heat of vaporization for water and some concentrated salt solutions.

  14. Phase behavior of concentrated hydroxypropyl methylcellulose solution in the presence of mono and divalent salt.

    PubMed

    Almeida, Nalinda; Rakesh, Leela; Zhao, Jin

    2014-01-01

    Thermo reversible sol-gel transitions of hydroxypropylmethylcellulose (HPMC) are critical for many pharmaceutical, cosmetic, and food applications. This study examined the effects of salt (NaCl and CaCl₂) on the viscoelastic properties of concentrated low molecular weight HPMC solutions and found that the gelation temperature decreased linearly as a function of salt concentrations, independent of valency of cations and the mole concentration of anions. Thermal analysis showed that the depression of melting temperature can be fitted for both NaCl and CaCl₂ as a function of the total number of ions by a single linear curve, which was consistent with the melting point depression of pure water by NaCl and CaCl₂, but with a higher linear slope.

  15. A new procedure to measure effective molecular diffusion coefficients of salts solutions in building materials

    NASA Astrophysics Data System (ADS)

    Delgado, J. M. P. Q.

    2013-06-01

    The aim of this work is to present a mathematical and experimental formulation of a new simple procedure for the measurement of effective molecular diffusion coefficients of a salt solution in a water-saturated building material. This innovate experimental procedure and mathematical formulation is presented in detail and experimental values of "effective" molecular diffusion coefficient of sodium chloride in a concrete sample ( w/ c = 0.45), at five different temperatures (between 10 and 30 °C) and four different initial NaCl concentrations (between 0.1 and 0.5 M), are reported. The experimental results obtained are in good agreement with the theoretical and experimental values of molecular diffusion coefficient presented in literature. An empirical correlation is presented for the prediction of "effective" molecular diffusion coefficient over the entire range of temperatures and initial salt concentrations studied.

  16. Ionic conductivity of dual-phase polymer electrolytes comprised of NBR/SBR latex films swollen with lithium salt solutions

    SciTech Connect

    Matsumoto, Morihiko; Ichino, Toshihiro; Rutt, J.S.; Nishi, Shiro . NTT Interdisciplinary Research Lab.)

    1994-08-01

    Dual-phase polymer electrolytes (DPE) with high ionic conductivity and good mechanical strength were prepared by swelling poly(acrylonitrile-co-butadiene) rubber (NBR) and poly(styrene-co-butadiene) rubber (SBR) mixed latex films with lithium salt solutions (e.g., 1M LiClO[sub 4]/[gamma]-butyrolactone). The latex films retain particle morphology in the solid state. The NBR phase (formed from fused NBR latex particles) is polar and is impregnated selectively with polar lithium salt solutions, yielding ion-conductive channels, whereas the SBR phase (formed from fused SBR latex particles) is nonpolar and is not impregnated, providing a mechanically supportive matrix. The ionic conductivity of the DPE increased dramatically with increasing content of lithium salt solution, and higher amounts of solution were imbibed with increasing content of NBR relative to SBR. Several factors which affect the ionic conductivity of this system were examined, and the highest ionic conductivity (>10[sup [minus]3] S/cm) was obtained when either an NBR/SBR 70/30 (w/w) or a 50/50 (w/w) latex film was saturated with 1M LiClO[sub 4]/[gamma]-BL solution or 1M LiClO[sub 4]/[gamma]-BL/DME solution. Ion-conductive behavior changed critically with increasing lithium salt solution uptake. At low levels of lithium salt solution uptake, evidence suggested that ionic conductivity of the absorbed lithium salt solution was strongly influenced by the presence of the NBR in the ion-conductive channel, but at higher levels, the effects of the NBR were reduced and free'' lithium salt solution was present.

  17. Photochromism of a spiropyran and a diarylethene in bile salt aggregates in aqueous solution.

    PubMed

    Santos, Cerize S; Miller, Allyson C; Pace, Tamara C S; Morimitsu, Kentaro; Bohne, Cornelia

    2014-09-30

    Bile salt aggregates incorporate aqueous-insoluble photochromic compounds. The photochromism of a spiropyran (1, 1',3',3'-trimethyl-6-nitrospiro[2H-1]-benzopyran-2,2'-indoline) and a diarylethene derivative (2, 1,2-bis(2,4-dimethyl-5-phenyl-3-thienyl)-3,3,4,4,5,5-hexafluoro-1-cyclopentene) was quantified in different bile salt aggregates. These aggregates act as efficient hosts to solubilize aqueous insoluble photochromic compounds where either both isomers are nonpolar, for example, 2, or compounds where one isomer is hydrophobic and the other is more polar, for example, 1. Methodology was developed to determine molar absorptivity coefficients for solutions containing both isomers and to determine the photoconversion quantum yields under continuous irradiation. The methods were validated by determining parameters in homogeneous solution, which were the same as previously reported. In the case of the colored isomer of 1, the molar extinction coefficient in ethanol at 537 nm ((3.68 ± 0.03) × 10(4) cm(-1) M(-1)) was determined with higher precision. The quantum yields for the photoconversion between the isomers of 2 were shown to be the same in cyclohexane and in the aggregates of sodium cholate (NaCh), deoxycholate (NaDC), and taurocholate (NaTC), showing that bile salt aggregates are not sufficiently rigid to affect the equilibrium between the two possible conformers of the colorless form. In contrast, for 1 the quantum yields for the conversion from the colorless to the colored isomer were higher in bile salts than in ethanol, and the quantum yield was highest in the more hydrophobic aggregates of NaDC, followed by NaCh and then NaTC. The structure of the bile salt had no effect on the quantum yield for the conversion of the colored to the colorless isomer of 1, but these values were higher than in ethanol. For all three bile salts, the absorption maximum for the colored form of 1 suggested that this isomer was located in an environment that is more polar than

  18. RESULTS OF ANALYSES OF MACROBATCH 3 DECONTAMINATED SALT SOLUTION (DSS) COALESCER AND PRE-FILTERS

    SciTech Connect

    Peters, T.; Fondeur, F.; Fink, S.

    2012-06-13

    SRNL analyzed the pre-filter and Decontamination Salt Solution (DSS) coalescer from MCU by several analytical methods. The results of these analyses indicate that overall there is light to moderate solids fouling of both the coalescer and pre-filter elements. The majority of the solids contain aluminum, sodium, silicon, and titanium, in oxide and/or hydroxide forms that we have noted before. The titanium is presumably precipitated from leached, dissolved monosodium titanate (MST) or fines from MST at ARP, and the quantity we find is significantly greater than in the past. A parallel report discusses potential causes for the increased leaching rate of MST, showing that increases in free hydroxide concentration of the feed solutions and of chemical cleaning solutions lead to faster leaching of titanium.

  19. The use of saline W, a physiological salt solution for experimentation on insect immunity.

    PubMed

    Jarosz, J

    1988-01-01

    In a series of induction experiments using various Ringer solutions attempts were made to determine whether saline W, a physiological salt solution for Lepidoptera, when injected into the larval haemocoel of the greater wax moth could be recognized by the insect as a non-self molecule. Laboratory bioassays indicated the loss of insect body integrity following intracoelomic injection of saline W and three other salines, increased levels of haemolymph lysozyme activity (EC 3. 2. 1. 17), and elevated resistance to the bacterial parasite, Pseudomonas aeruginosa. The inducing effect of saline W was stronger than dipterous Ringer's solution or other physiological salines. The stimulating effects indicate that the moth distinguishes between self and non-self, and this provides a new insight into the induction of the immune response.

  20. Salt II: Toward Security or Danger? A Balanced Account of the Key Issues in the Debate.

    ERIC Educational Resources Information Center

    Irwin, Wallace, Jr., Ed.; And Others

    Facts and controversial issues concerning SALT II (Strategic Arms Limitations Talks) are examined. The intent of the document is to enable non-specialists in military/strategic matters to arrive at their own conclusions. Central questions explored are: Is it possible to arrive at an agreement that will stabilize strategic arms competition and…

  1. Salt II: Toward Security or Danger? A Balanced Account of the Key Issues in the Debate.

    ERIC Educational Resources Information Center

    Irwin, Wallace, Jr., Ed.; And Others

    Facts and controversial issues concerning SALT II (Strategic Arms Limitations Talks) are examined. The intent of the document is to enable non-specialists in military/strategic matters to arrive at their own conclusions. Central questions explored are: Is it possible to arrive at an agreement that will stabilize strategic arms competition and…

  2. Water and salt balance in young male football players in training during the holy month of Ramadan.

    PubMed

    Shirreffs, Susan M; Maughan, Ronald J

    2008-12-01

    The aim of this study was to assess water and salt balance in young football players in training during Ramadan. Measurements were made in 92 young male football players before and during the month of Ramadan. Fifty-five participants were observing Ramadan fasting, while the other 37 participants were eating and drinking without restriction. In week 3 of Ramadan, water and salt balance measures were made during a training session of 60-70 min duration that was performed at an ambient temperature of 25-28 degrees C and relative humidity of 50-53%. Body mass was recorded before and after training. Fluid intake was assessed in non-fasting players by weighing drink bottles before and after training, and the volume of any urine output was recorded. Sweat composition was estimated from absorbent patches applied to four skin sites for the duration of training. Mean sweat loss of players amounted to 1.41 litres (s = 0.36) in fasting players and 1.61 litres (s = 0.51) in non-fasting players (P = 0.038). Mean fluid intake during training in non-fasting players was 1.92 litres (s = 0.66). Sweat sodium concentration was 20 mmol . l(-1) (s = 8) in fasting players and 17 mmol . l(-1) (s = 7) in non-fasting players, and total sweat sodium loss during training was 0.67 g (s = 0.41) and 0.65 g (s = 0.37) [corresponding to a salt loss of 1.7 g (s = 1.1) and 1.7 g (s = 0.9)] respectively, with no difference between fasting and non-fasting players. Sweat sodium loss was not related to estimated dietary sodium intake (r = -0.07). These descriptive data show large individual variations in all measured parameters with relatively little difference in sweat parameters between fasting and non-fasting individuals.

  3. Continuation of quasi-periodic solutions with two-frequency Harmonic Balance Method

    NASA Astrophysics Data System (ADS)

    Guillot, Louis; Vigué, Pierre; Vergez, Christophe; Cochelin, Bruno

    2017-04-01

    The continuation of quasi-periodic solutions for autonomous or forced nonlinear systems is presented in this paper. The association of the Asymptotic Numerical Method, a robust continuation method, and a two-frequency Harmonic Balance Method, is performed thanks to a quadratic formalism. There is no need for a priori knowledge of the solution: the two pulsations can be unknown and can vary along the solution branch, and the double Fourier series are computed without needing a harmonic selection. A norm criterion on Fourier coefficients can confirm a posteriori the accuracy of the solution branch. On a forced system, frequency-locking regions are approximated, without blocking the continuation process. The continuation of these periodic solutions can be done independently. On an autonomous system an example of solution is shown where the number of Fourier coefficients is increased to improve the accuracy of the solution.

  4. Equilibrium, kinetic and thermodynamic study of cesium adsorption onto nanocrystalline mordenite from high-salt solution.

    PubMed

    Lee, Keun-Young; Park, Minsung; Kim, Jimin; Oh, Maengkyo; Lee, Eil-Hee; Kim, Kwang-Wook; Chung, Dong-Yong; Moon, Jei-Kwon

    2016-05-01

    In this study, the equilibrium, kinetics and thermodynamics of cesium adsorption by nanocrystalline mordenite were investigated under cesium contamination with high-salt solution, simulating the case of an operation and decommissioning of nuclear facilities or an accident during the processes. The adsorption rate constants were determined using a pseudo second-order kinetic model. The kinetic results strongly demonstrated that the cesium adsorption rate of nano mordenite is extremely fast, even in a high-salt solution, and much faster than that of micro mordenite. In the equilibrium study, the Langmuir isotherm model fit the cesium adsorption data of nano mordenite better than the Freundlich model, which suggests that cesium adsorption onto nano mordenite is a monolayer homogeneous adsorption process. The obtained thermodynamic parameters indicated that the adsorption involved a very stable chemical reaction. In particular, the combination of rapid particle dispersion and rapid cesium adsorption of the nano mordenite in the solution resulted in a rapid and effective process for cesium removal without stirring, which may offer great advantages for low energy consumption and simple operation.

  5. Aggregate transitions in aqueous solutions of sodium dodecylsulfate with a "gemini-type" organic salt.

    PubMed

    Yu, Defeng; Tian, Maozhang; Fan, Yaxun; Ji, Gang; Wang, Yilin

    2012-06-07

    Effects of a "gemini-type" organic salt 1,2-bis(2-benzylammoniumethoxy) ethane dichloride (BEO) on the aggregation behavior of sodium dodecylsulfate (SDS) have been investigated by turbidity, surface tension, isothermal titration microcalorimetry, dynamic light scattering, cryogenic transmission electron microscopy, (1)H NMR spectroscopy, and differential scanning microcalorimetry. The aggregation behavior of the SDS/BEO mixed aqueous solution shows strong concentration and ratio dependence. For the SDS/BEO solution with a molar ratio of 5:1, large loose irregular aggregates, vesicles, and long thread-like micelles are formed in succession with the increase of the total SDS and BEO concentration. Because BEO has two positive charges, the SDS/BEO solution may consist of the (SDS)(2)-BEO gemini-type complex, the SDS-BEO complex and extra SDS. The aggregation ability and surface activity of the SDS/BEO mixture exhibit the characteristics of gemini-type surfactants. Along with the results of DSC and (1)H NMR, the (SDS)(2)-BEO gemini-type structure is confirmed to exist in the system. This work provides an approach to construct the surfactant systems with the characteristics of gemini surfactants through intermolecular interaction between a two-charged organic salt and oppositely charged single-chain surfactants.

  6. Water--Problems and Solutions. A Report Concerning the Problems and Solutions of Negative Water Balance.

    ERIC Educational Resources Information Center

    Ewert, Alan

    Outdoor leaders constantly face problems created by water shortage and, to act effectively, must thoroughly understand the body's use of water and the ways to delay dehydration when water shortage occurs. Dehydration begins when there is a negative water balance, or more water lost than ingested, and progresses from the stage of dryness, to the…

  7. Effects of coprecipitation on uranium and plutonium concentrations in alkaline salt solutions

    SciTech Connect

    Hobbs, D.T.

    1997-03-19

    The chemistry of uranium and plutonium in conjunction with the storage, retrieval and treatment of high-level nuclear waste (HLW) has been the subject of increasing scrutiny due to concerns with nuclear criticality safety. Previous studies focused on determining the solubilities of plutonium and uranium in alkaline salt solutions that encompass the compositions present during storage and evaporation of fresh and aged. Recent studies extend the chemistry to include the effects of coprecipitation on the liquid phase concentrations of plutonium and uranium. Particle size, morphology and identification of crystalline phases in the precipitated solids as well as the plutonium and uranium dissolution characteristics upon dilution of the liquid phases were also determined.

  8. Electrically conducting poly(para-phenylene sulfide) prepared by doping with nitrosyl salts from solution

    NASA Astrophysics Data System (ADS)

    Rubner, Michael; Cukor, Peter; Jopson, Harriet; Deits, Walter

    1982-03-01

    Para(polyphenylene sulfide) may be doped spontaneously and rapidly with nitrosyl salts (NOPF6, NOSbF6) from solution to yield an electrically conducting material (10-1ohm-1cm-1). The level of conductivity is primarily dependent on the extent of dopant incorporation, which in turn is determined by the polymer’s crystallinity; the more amorphous the polymer, the more dopant it takes up and the more conductive it becomes. The incorporation of dopants produces irreversible chemical changes in the polymer resulting in the deterioration of its mechanical properties.

  9. Partial and charge structure fonctions of monodisperse DNA fragments in salt free aqueous solution

    NASA Astrophysics Data System (ADS)

    van der Maarel, J. R. C.; Groot, L. C. A.; Mandel, M.; Jesse, W.; Jannink, G.; Rodriguez, V.

    1992-01-01

    Observations of the partial structure functions and the charge structure function are reported for an aqueous solution of monodisperse rodlike DNA fragments, without added simple salt. In the reciprocal space interval qgeqslant 0.075 Å^{-1}, the neutron scattering data can be fitted by the correlation functions derived from the exact solution of the Poisson-Boltzmann equation in the cell model. The fit is equally good for all partial structure functions as well as the charge structure function. The cell model seems to be appropriate for this kind of solution. On reconstitue la structure d'une solution aqueuse de fragments monodisperse d'ADN à l'aide des fonctions de structure partielles et de la fonction de structure de charge mesurées par diffusion des neutrons aux petits angles. Dans l'intervalle qgeqslant 0,075 Å^{-1}, les fonctions de corrélation calculées à partir de la solution exacte de l'équation de Poisson-Boltzmann et du modèle cellulaire, ajustent les données de l'expérience. Cela est vrai aussi bien pour chacune des fonctions de structure partielles que pour la fonction de structure de charge. Le modèle cellulaire semble donc être un modèle convenable pour ces solutions.

  10. Super-absorbency and phase transition of gels in physiological salt solutions

    NASA Astrophysics Data System (ADS)

    Zhang, Yong-Qing; Tanaka, Toyoichi; Shibayama, Mitsuhiro

    1992-11-01

    IONIC gels with the ability to absorb many times their dry weight of water have found widespread use as absorbents in medical, chemical and agricultural applications1. The dramatic swelling power of these super-absorbent gels results from both the electrostatic repulsion between the charges on the polymer chains, and the osmotic pressure of the counter-ions2. In salt solutions such as saline, urine or blood, however, excess Na+ and Cl- ions screen the polymer charges and eliminate the osmotic imbalance, effectively changing the properties of the material to that of a non-ionic gel3: this greatly diminishes the swelling power, and hence the utility of these materials under physiological conditions. Here we report the development of a system combining a non-ionic gel with ionized surfactants, which shows super-absorbent behaviour even in the presence of salt. In water, the hydrophobic gel facilitates the formation of spherical surfactant micelles, which mimic the charged sites of an ionic gel. As the salt concentration is increased, the micelles become rod-like, maintaining the electrostatic repulsion along the polymer chains and thereby preserving the swelling power of the gel.

  11. Molecular Dynamics Simulation of the Aggregation Patterns in Aqueous Solutions of Bile Salts at Physiological Conditions.

    PubMed

    Mustan, Fatmegyul; Ivanova, Anela; Madjarova, Galia; Tcholakova, Slavka; Denkov, Nikolai

    2015-12-24

    Classical molecular dynamics simulations are employed to monitor the aggregation behavior of six bile salts (nonconjugated and glycine- and taurine-conjugated sodium cholate and sodium deoxycholate) with concentration of 10 mM in aqueous solution in the presence of 120 mM NaCl. There are 150 ns trajectories generated to characterize the systems. The largest stable aggregates are analyzed to determine their shape, size, and stabilizing forces. It is found that the aggregation is a hierarchical process and that its kinetics depends both on the number of hydroxyl groups in the steroid part of the molecules and on the type of conjugation. The micelles of all salts are similar in shape-deformed spheres or ellipsoids, which are stabilized by hydrophobic forces, acting between the steroid rings. The differences in the aggregation kinetics of the various conjugates are rationalized by the affinity for hydrogen bond formation for the glycine-modified salts or by the longer time needed to achieve optimum packing for the tauro derivatives. Evidence is provided for the hypothesis from the literature that the entirely hydrophobic core of all aggregates and the enhanced dynamics of the molecules therein should be among the prerequisites for their pronounced solubilization capacity for hydrophobic substances in vivo.

  12. Modeling of dielectric properties of aqueous salt solutions with an equation of state.

    PubMed

    Maribo-Mogensen, Bjørn; Kontogeorgis, Georgios M; Thomsen, Kaj

    2013-09-12

    The static permittivity is the most important physical property for thermodynamic models that account for the electrostatic interactions between ions. The measured static permittivity in mixtures containing electrolytes is reduced due to kinetic depolarization and reorientation of the dipoles in the electrical field surrounding ions. Kinetic depolarization may explain 25-75% of the observed decrease in the permittivity of solutions containing salts, but since this is a dynamic property, this effect should not be included in the thermodynamic modeling of electrolytes. Kinetic depolarization has, however, been ignored in relation to thermodynamic modeling, and authors have either neglected the effect of salts on permittivity or used empirical correlations fitted to the measured static permittivity, leading to an overestimation of the reduction in the thermodynamic static permittivity. We present a new methodology for obtaining the static permittivity over wide ranges of temperatures, pressures, and compositions for use within an equation of state for mixed solvents containing salts. The static permittivity is calculated from a new extension of the framework developed by Onsager, Kirkwood, and Fröhlich to associating mixtures. Wertheim's association model as formulated in the statistical associating fluid theory is used to account for hydrogen-bonding molecules and ion-solvent association. Finally, we compare the Debye-Hückel Helmholtz energy obtained using an empirical model with the new physical model and show that the empirical models may introduce unphysical behavior in the equation of state.

  13. Interconnection of Salt-induced Hydrophobic Compaction and Secondary Structure Formation Depends on Solution Conditions

    PubMed Central

    Haldar, Shubhasis; Chattopadhyay, Krishnananda

    2012-01-01

    What happens in the early stage of protein folding remains an interesting unsolved problem. Rapid kinetics measurements with cytochrome c using submillisecond continuous flow mixing devices suggest simultaneous formation of a compact collapsed state and secondary structure. These data seem to indicate that collapse formation is guided by specific short and long range interactions (heteropolymer collapse). A contrasting interpretation also has been proposed, which suggests that the collapse formation is rapid, nonspecific, and a trivial solvent related compaction, which could as well be observed by a homopolymer (homopolymer collapse). We address this controversy using fluorescence correlation spectroscopy (FCS), which enables us to monitor the salt-induced compaction accompanying collapse formation and the associated time constant directly at single molecule resolution. In addition, we follow the formation of secondary structure using far UV CD. The data presented here suggest that both these models (homopolymer and heteropolymer) could be applicable depending on the solution conditions. For example, the formation of secondary structure and compact state is not simultaneous in aqueous buffer. In aqueous buffer, formation of the compact state occurs through a two-state co-operative transition following heteropolymer formalism, whereas secondary structure formation takes place gradually. In contrast, in the presence of urea, a compaction of the protein radius occurs gradually over an extended range of salt concentration following homopolymer formalism. The salt-induced compaction and the formation of secondary structure take place simultaneously in the presence of urea. PMID:22303014

  14. Glyme-lithium salt equimolar molten mixtures: concentrated solutions or solvate ionic liquids?

    PubMed

    Ueno, Kazuhide; Yoshida, Kazuki; Tsuchiya, Mizuho; Tachikawa, Naoki; Dokko, Kaoru; Watanabe, Masayoshi

    2012-09-13

    To demonstrate a new family of ionic liquids (ILs), i.e., "solvate" ionic liquids, the properties (thermal, transport, and electrochemical properties, Lewis basicity, and ionicity) of equimolar molten mixtures of glymes (triglyme (G3) and tetraglyme (G4)) and nine different lithium salts (LiX) were investigated. By exploring the anion-dependent properties and comparing them with the reported data on common aprotic ILs, two different classes of liquid regimes, i.e., ordinary concentrated solutions and "solvate" ILs, were found in the glyme-Li salt equimolar mixtures ([Li(glyme)]X) depending on the anionic structures. The class a given [Li(glyme)]X belonged to was governed by competitive interactions between the glymes and Li cations and between the counteranions (X) and Li cations. [Li(glyme)]X with weakly Lewis basic anions can form long-lived [Li(glyme)](+) complex cations. Thus, they behaved as typical ionic liquids. The lithium "solvate" ILs based on [Li(glyme)]X have many desirable properties for lithium-conducting electrolytes, including high ionicity, a high lithium transference number, high Li cation concentration, and high oxidative stability, in addition to the common properties of ionic liquids. The concept of "solvate" ionic liquids can be utilized in an unlimited number of combinations of other metal salts and ligands, and will thus open a new field of research on ionic liquids.

  15. Description of the Material Balance Model and Spreadsheet for Salt Dissolution

    SciTech Connect

    Wiersma, B.J.

    1994-10-12

    The model employed to estimate the amount of inhibitors necessary for bearing water and dissolution water during the salt dissolution process is described. This model was inputed on a spreadsheet which allowed many different case studies to be performed. This memo describes the assumptions and equations which are used in the model, and documents the input and output cells of the spreadsheet. Two case studies are shown as examples of how the model may be employed.

  16. Balance between salt stress and endogenous hormones influence dry matter accumulation in Jerusalem artichoke.

    PubMed

    Shao, Tianyun; Li, Lingling; Wu, Yawen; Chen, Manxia; Long, Xiaohua; Shao, Hongbo; Liu, Zhaopu; Rengel, Zed

    2016-10-15

    Salinity is one of the most serious environmental stresses limiting agricultural production. Production of Jerusalem artichoke on saline land is strategically important for using saline land resources. The interaction between plant hormones and salinity stress in governing Jerusalem artichoke (Helianthus tuberosus) growth is unclear. Jerusalem artichoke (variety Nanyu-1) was grown under variable salinity stress in the field, and a role of endogenous hormones [zeatin (ZT), auxins (IAA), gibberellins (GA3) and abscisic acid (ABA)] in regulating sugar and dry matter accumulation in tubers was characterized. Under mild salt stress (≤2.2gNaClkg(-1) soil), Nanyu-1 grew well with no significant alteration of dry matter distribution to stems and tubers. In contrast, under moderate salt stress (2.7gNaClkg(-1) soil), the distribution to stem decreased and to tubers decreased significantly. Mild salt stress induced sugar accumulation in tubers at the beginning of the tuber-expansion period, but significantly inhibited (i) transfer of non-reducing sugars to tubers, and (ii) polymerization and accumulation of fructan during the tuber-expansion stage. Under different salinity stress, before the stolon growth, the ratio of IAA/ABA in leaves increased significantly and that of GA3/ABA increased slightly; during tuber development, these ratios continued to decrease and reached the minimum late in the tuber-expansion period. While, salt stress inhibited (i) underground dry matter accumulation, (ii) tuber dry matter accumulation efficiency, (iii) transport of non-reducing sugars to tubers, and (iv) fructan accumulation efficiency during the tuber-expansion period; these effects were accompanied by significantly decreased tuber yield with an increase in salinity. With soil salinity increasing, the synthesis of IAA and GA3 was inhibited in leaves and tubers, while ABA synthesis was stimulated. In brief, tuber yield would significantly decreased with the increase of salinity

  17. Combined influence of ectoine and salt: spectroscopic and numerical evidence for compensating effects on aqueous solutions.

    PubMed

    Hahn, Marc Benjamin; Uhlig, Frank; Solomun, Tihomir; Smiatek, Jens; Sturm, Heinz

    2016-10-19

    Ectoine is an important osmolyte, which allows microorganisms to survive in extreme environmental salinity. The hygroscopic effects of ectoine in pure water can be explained by a strong water binding behavior whereas a study on the effects of ectoine in salty solution is yet missing. We provide Raman spectroscopic evidence that the influence of ectoine and NaCl are opposing and completely independent of each other. The effect can be explained by the formation of strongly hydrogen-bonded water molecules around ectoine which compensate the influence of the salt on the water dynamics. The mechanism is corroborated by first principles calculations and broadens our understanding of zwitterionic osmolytes in aqueous solution. Our findings allow us to provide a possible explanation for the relatively high osmolyte concentrations in halotolerant bacteria.

  18. Polyelectrolyte-like behaviour of poly(ethylene-oxide) solutions with added monovalent salt

    NASA Astrophysics Data System (ADS)

    Lal, Jyotsana; Hakem, Ilhem-Faiza

    2004-03-01

    Solvent effects on the conformation of poly(ethylene-oxide) (PEO) and complexation of PEO by monovalent cations, have been examined by using small-angle neutron scattering. In methanol and acetonitrile, a big change in interchain interaction, osmotic compressibility and local chain conformation have been observed upon addition of small amounts of potassium iodide. The amplitude of the total intensity decreases significantly and a peak at a certain value of the wavevector q* appears as signature of a polyelectrolyte-like behaviour. With further addition of salt, the ionic strength of the solution increases and potassium binding becomes less favorable: the binding constant decreases with the ionic strength and PEO behaves as a neutral polymer with excluded volume. No association between PEO and potassium iodide was observed in aqueous solutions. Reference: I.F. Hakem and J. Lal. Europhysics letters, 64 (2), 204, 2003

  19. Evaluation of poly (aspartic acid sodium salt) as a draw solute for forward osmosis.

    PubMed

    Gwak, Gimun; Jung, Bokyung; Han, Sungsoo; Hong, Seungkwan

    2015-09-01

    Poly (aspartic acid sodium salt) (PAspNa) was evaluated for its potential as a novel draw solute in forward osmosis (FO). The inherent advantages of PAspNa, such as good water solubility, high osmotic pressure, and nontoxicity, were first examined through a series of physicochemical analyses and atomic-scale molecular dynamics simulations. Then, lab-scale FO tests were performed to evaluate its suitability in practical processes. Compared to other conventional inorganic solutes, PAspNa showed comparable water flux but significantly lower reverse solute flux, demonstrating its suitability as a draw solute. Moreover, fouling experiments using synthetic wastewater as a feed solution demonstrated that PAspNa reversely flowed to the feed side reduced inorganic scaling on the membrane active layer. The recyclability of PAspNa was studied using both nanofiltration (NF) and membrane distillation (MD) processes, and the results exhibited its ease of recovery. This research reported the feasibility and applicability of FO-NF or FO-MD processes using PAspNa for wastewater reclamation and brackish water desalination. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Synergistic solubilization of porcine myosin in physiological salt solution by arginine.

    PubMed

    Takai, Eisuke; Yoshizawa, Shunsuke; Ejima, Daisuke; Arakawa, Tsutomu; Shiraki, Kentaro

    2013-11-01

    Myosin is an important protein resource for food industries and has a bipolar filamentous structure that is composed of subfilaments that occur in vivo. It has been shown that a high ionic strength is required to prevent myosin from forming filamentous structures and to solubilize the protein in aqueous solution. In the presence of 100-200 mM NaCl, 50 mM arginine was more effective than other additives tested, including NaCl, in myosin solubilization. Before reaching equilibrium solubility, the myosin solution was initially supersaturated upon the dilution of a stock myosin solution in 1 M NaCl into the test solvents. Arginine slowed the process of equilibration and stabilized the supersaturated solution more effectively than other additives. No structural changes in myosin caused by arginine were observed, which indicated that arginine enhanced the solubility of myosin in a physiological salt solution without affecting the structure. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Changes in mechanical properties and morphology of elastomer coatings after immersion in salt solutions

    NASA Astrophysics Data System (ADS)

    Terán Arce, Fernando; Avci, Recep; Beech, Iwona; Cooksey, Keith; Wigglesworth-Cooksey, Barbara

    2004-03-01

    RTV11 (^TM GE Silicones) and Intersleek (^TM International Paints) are two elastomers of considerable significance to the navy and maritime industry for their application as fouling release coatings. Both materials are composed of polymeric matrices with embedded filler particles, which provide increased strength and durability to the elastomer. Using Atomic force microscopy (AFM), surface and bulk analysis techniques, we have found surface regions with microelastic properties, which correlate with the locations of filler particles inside the coatings. These particles are able to undergo elastic displacements of hundreds of nm inside the polymeric matrix during compression by the AFM tip. While elastic properties of Intersleek remain largely unchanged after immersion in salt solutions, roughening, embrittlement and stiffening occurs in RTV11 coatings depending on the amount of curing agent and humidity used during preparation and curing, respectively. Interestingly, such transformations are absent after immersion in pure water. In particle free regions, elastic moduli of RTV11 take values of 2 - 3 MPa before immersion in salt solutions. After immersion, those values increase 5 - 10 times.

  2. Comparison of peak shape in hydrophilic interaction chromatography using acidic salt buffers and simple acid solutions.

    PubMed

    Heaton, James C; Russell, Joseph J; Underwood, Tim; Boughtflower, Robert; McCalley, David V

    2014-06-20

    The retention and peak shape of neutral, basic and acidic solutes was studied on hydrophilic interaction chromatography (HILIC) stationary phases that showed both strong and weak ionic retention characteristics, using aqueous-acetonitrile mobile phases containing either formic acid (FA), ammonium formate (AF) or phosphoric acid (PA). The effect of organic solvent concentration on the results was also studied. Peak shape was good for neutrals under most mobile phase conditions. However, peak shapes for ionised solutes, particularly for basic compounds, were considerably worse in FA than AF. Even neutral compounds showed deterioration in performance with FA when the mobile phase water concentration was reduced. The poor performance in FA cannot be entirely attributed to the negative impact of ionic retention on ionised silanols on the underlying silica base materials, as results using PA at lower pH (where their ionisation is suppressed) were inferior to those in AF. Besides the moderating influence of the salt cation on ionic retention, it is likely that salt buffers improve peak shape due to the increased ionic strength of the mobile phase and its impact on the formation of the water layer on the column surface. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Composite Properties of Polyimide Resins Made From "Salt-Like" Solution Precursors

    NASA Technical Reports Server (NTRS)

    Cano, Roberto J.; Weiser, Erik S.; SaintClair, Terry L.; Echigo, Yoshiaki; Kaneshiro, Hisayasu

    1997-01-01

    Recent work in high temperature materials at NASA Langley Research Center (LaRC (trademark)) have led to the development of new polyimide resin systems with very attractive properties. The majority of the work done with these resin systems has concentrated on determining engineering mechanical properties of composites prepared from a poly(amide acid) precursor. Three NASA Langley-developed polyimide matrix resins, LaRC (trademark) -IA, LaRC (trademark) -IAX, and LaRC (trademark) -8515, were produced via a salt-like process developed by Unitika Ltd. The 'salt-like' solutions (sixty-five percent solids in NMP) were prepregged onto Hexcel IM7 carbon fiber using the NASA LaRC Multipurpose Tape Machine. Process parameters were determined and composite panels fabricated. Mechanical properties are presented for these three intermediate modulus carbon fiber/polyimide matrix composites and compared to existing data on the same polyimide resin systems and IM7 carbon fiber manufactured via poly(amide acid) solutions (thirty-five percent solids in NMP). This work studies the effects of varying the synthetic route on the processing and mechanical properties of polyimide composites.

  4. Formation and stabilization of anionic metal complexes in concentrated aqueous quaternary ammonium salt solutions

    SciTech Connect

    Aronson, F.L.; Hwang, L.L.Y.; Ronca, N.; Solomon, N.A.; Steigman, J.

    1985-02-04

    Anionic complexes of transition metals were stabilized in aqueous solutions containing high concentrations of various short-chain quaternary ammonium salts. Compounds with longer paraffin chains were effective in much less concentrated solution. Complex ions were detected spectrophotometrically. FeCl/sub 4//sup -/, which is usually formed in concentrated HCl, was the predominant Fe(III) complex in 30 m choline chloride containing only 0.12 M HCl. A yellow transitory Tc(VII) chloro-addition intermediate, formed in the reduction of TcO/sub 4//sup -/ by concentrated HCl, was stabilized when the solution also contained 25 m choline chloride. Its spectrum, as well as the isolation of an already known Tc(VII) bipyridyl complex, is reported. Concentrated organic electrolytes also stabilized Tc(V) oxide halides against disproportionation and Tc(IV) hexahalides against hydrolysis. Halochromates of Cr(VI) were formed and stabilized in dilute acid containing quaternary ammonium salts. Their UV spectra showed the well-resolved vibronic fine structure associated with the symmetric chromium-to-oxygen charge-transfer band. It is known that these progressions are resolved in aprotic solvents, but not in aqueous acidic solution alone, and that the loss of fine structure in aqueous media is due to hydrogen bonding. The stabilization of anionic metal complexes and the resolution of vibronic structure in halochromates are probably consequences of water-structure-enforced ion paring. The present work suggests that the water molecules in immediate contact with the complex anions are more strongly hydrogen bonded to each other than to the complex. 21 references, 4 figures.

  5. Implicit, semi-analytical solution of the generalized Riemann problem for stiff hyperbolic balance laws

    NASA Astrophysics Data System (ADS)

    Toro, Eleuterio F.; Montecinos, Gino I.

    2015-12-01

    We present a semi-analytical, implicit solution to the generalized Riemann problem (GRP) for non-linear systems of hyperbolic balance laws with stiff source terms. The solution method is based on an implicit, time Taylor series expansion and the Cauchy-Kowalewskaya procedure, along with the solution of a sequence of classical Riemann problems. Our new GRP solver is then used to construct locally implicit ADER methods of arbitrary accuracy in space and time for solving the general initial-boundary value problem for non-linear systems of hyperbolic balance laws with stiff source terms. Analysis of the method for model problems is carried out and empirical convergence rate studies for suitable tests problems are performed, confirming the theoretically expected high order of accuracy.

  6. Salt Marsh Net Ecosystem Carbon Balance: Improving Methods to Quantify the Role of Lateral (Tidal) Exchanges

    NASA Astrophysics Data System (ADS)

    Kroeger, K. D.

    2016-02-01

    Coastal wetlands are prime candidates for greenhouse gas emission offsets as they display extraordinarily high rates of carbon (C) sequestration. However, lack of data about rates of and controls on C sequestration in tidal wetlands, as well as substantial temporal and spatial heterogeneity, complicate development of both models and a methodology for use by C registries. The goals of our field research are to improve understanding of the climatic role of coastal wetlands, quantify potential for GHG emission offsets through restoration or preservation, and quantify impacts of eutrophication and other environmental factors. Among our objectives is to construct C and greenhouse gas (GHG) budgets for salt marshes, based on measurements of GHG exchanges with the atmosphere, C storage in soils, and lateral (tidal) exchanges of gases, C, and sediment. In this presentation, emphasis is on rate and source of tidal exchanges between salt marshes and adjacent estuaries. We measured fluxes by collecting high frequency data on tidal water flows and physical and chemical conditions in wetland channels using acoustic and optical sensors, as well as laser absorption spectrometry. To provide site-specific calibrations of sensors, we collected water samples across tidal cycles and seasons. Source investigations include analysis of stable isotope and lipid compositions. We used multiple regressions to estimate dissolved organic (DOC) and inorganic carbon (DIC) concentrations at high frequency over extended time. Carbon flux was calculated as the product of concentration and water flux, corrected for modeled flow outside of the tidal creek. Annual rates of net C flux from wetland to estuary indicate that both DOC and DIC are large terms in the salt marsh carbon budget relative to net exchange with the atmosphere and rate of storage in soil, and that DIC flux may have been underestimated in previous studies.

  7. Observation of salt effects on hydration water of lysozyme in aqueous solution using terahertz time-domain spectroscopy

    NASA Astrophysics Data System (ADS)

    Aoki, Katsuyoshi; Shiraki, Kentaro; Hattori, Toshiaki

    2013-10-01

    Terahertz time-domain spectroscopy was used to investigate the salt effect of ammonium sulfate on the dynamics of hydration water of lysozyme in aqueous solution. The absorption coefficient of lysozyme aqueous solutions containing salt was subtracted by that of the water and ammonium sulfate contained in the lysozyme solution. The results revealed that ammonium sulfate increases the absorption coefficient of the hydration water, which indicates that the dynamics of the hydration water becomes faster and/or the number of hydration water molecules decreases with increasing ammonium sulfate concentration.

  8. Determining the Enthalpy of Vaporization of Salt Solutions Using the Cooling Effect of a Bubble Column Evaporator

    ERIC Educational Resources Information Center

    Fan, Chao; Pashley, Richard M.

    2016-01-01

    The enthalpy of vaporization (?H[subscript vap]) of salt solutions is not easily measured, as a certain quantity of pure water has to be evaporated from a solution, at constant composition, and at a fixed temperature and pressure; then the corresponding heat input has to be measured. However, a simple bubble column evaporator (BCE) was used as a…

  9. Determining the Enthalpy of Vaporization of Salt Solutions Using the Cooling Effect of a Bubble Column Evaporator

    ERIC Educational Resources Information Center

    Fan, Chao; Pashley, Richard M.

    2016-01-01

    The enthalpy of vaporization (?H[subscript vap]) of salt solutions is not easily measured, as a certain quantity of pure water has to be evaporated from a solution, at constant composition, and at a fixed temperature and pressure; then the corresponding heat input has to be measured. However, a simple bubble column evaporator (BCE) was used as a…

  10. A simple field test for assessing salt balance in heat-stressed miners

    SciTech Connect

    Cross, R.B.; Galton-Fenzi, B.; Jordan, L. )

    1989-08-01

    A simple colorimetric test for urinary chloride (Fantus test) corrected for urine specific gravity (measured by refractometry) enabled 24-hour urinary sodium excretion rates to be predicted accurately from a single spot sample of urine. In 29 acclimatized miners working in an environment in excess of 40 degrees C, salt-conserving mechanisms, involving renin and aldosterone, were not active until the urinary sodium excretion rate fell below 50 mmol/24 h. A predicted sodium excretion rate greater than 50 mmol/24 h indicates that dietary sodium supplementation is not necessary.

  11. A comparison of balanced and unbalanced crystalloid solutions in surgery patient outcomes.

    PubMed

    Kuca, Tomas; Butler, Michael B; Erdogan, Mete; Green, Robert S

    2016-11-14

    The objective of this study was to evaluate adverse patient outcomes associated with the choice of intravenous fluid administered during general anaesthesia. This study was a retrospective chart review of vascular surgery patients at a Canadian tertiary care hospital. Patients were separated into three groups: those who were intraoperatively administered normal saline (NS), balanced crystalloids, or a combination of both solutions. Multivariate analysis was performed to determine association between volume of each fluid type administered and adverse outcomes including in-hospital mortality, prolonged intensive care unit admission, vasopressor requirement, ventilator requirement, hemodialysis requirement, and a composite endpoint of any of these adverse events occurring. Overall, 796 vascular surgery patients were included in the analysis. There were 425 patients who received balanced crystalloids, 158 patients who received NS, and 213 patients received both balanced crystalloids and NS. Groups were similar in age (P=0.06), but varied in gender (P<0.001) and overall health (ASA≥2; P=0.027). The most common adverse event was ventilator requirement (NS: 27.9%, balanced: 7.5%, both: 38.0%; P<0.001). Mortality was lowest in the group that received balanced fluids (NS: 12.0%, balanced: 5.9%, both: 10.8%; P=0.018). Patients who were administered NS or both fluids were more likely to reach the composite endpoint than patients receiving balanced crystalloid alone. The administration of an unbalanced crystalloid solution was associated with poor patient outcomes in our study population. Copyright © 2016 Société française d'anesthésie et de réanimation (Sfar). Published by Elsevier Masson SAS. All rights reserved.

  12. The effect of sea ice loss on sea salt aerosol concentrations and the radiative balance in the Arctic

    NASA Astrophysics Data System (ADS)

    Struthers, H.; Ekman, A. M. L.; Glantz, P.; Iversen, T.; Kirkevåg, A.; Mårtensson, E. M.; Seland, Ø.; Nilsson, E. D.

    2011-04-01

    Understanding Arctic climate change requires knowledge of both the external and the local drivers of Arctic climate as well as local feedbacks within the system. An Arctic feedback mechanism relating changes in sea ice extent to an alteration of the emission of sea salt aerosol and the consequent change in radiative balance is examined. A set of idealized climate model simulations were performed to quantify the radiative effects of changes in sea salt aerosol emissions induced by prescribed changes in sea ice extent. The model was forced using sea ice concentrations consistent with present day conditions and projections of sea ice extent for 2100. Sea salt aerosol emissions increase in response to a decrease in sea ice, the model results showing an annual average increase in number emission over the polar cap (70-90° N) of 86 × 106 m-2 s-1 (mass emission increase of 23 μg m-2 s-1). This in turn leads to an increase in the natural aerosol optical depth of approximately 23%. In response to changes in aerosol optical depth, the natural component of the aerosol direct forcing over the Arctic polar cap is estimated to be between -0.2 and -0.4 W m-2 for the summer months, which results in a negative feedback on the system. The model predicts that the change in first indirect aerosol effect (cloud albedo effect) is approximately a factor of ten greater than the change in direct aerosol forcing although this result is highly uncertain due to the crude representation of Arctic clouds and aerosol-cloud interactions in the model. This study shows that both the natural aerosol direct and first indirect effects are strongly dependent on the surface albedo, highlighting the strong coupling between sea ice, aerosols, Arctic clouds and their radiative effects.

  13. Measuring and modeling the salting-out effect in ammonium sulfate solutions.

    PubMed

    Wang, Chen; Lei, Ying Duan; Endo, Satoshi; Wania, Frank

    2014-11-18

    The presence of inorganic salts significantly influences the partitioning behavior of organic compounds between environmentally relevant aqueous phases, such as seawater or aqueous aerosol, and other, nonaqueous phases (gas phase, organic phase, etc.). In this study, salting-out coefficients (or Setschenow constants) (KS [M(-1)]) for 38 diverse neutral compounds in ammonium sulfate ((NH4)2SO4) solutions were measured using a shared headspace passive dosing method and a negligible depletion solid phase microextraction technique. The measured KS were all positive, varied from 0.216 to 0.729, and had standard errors in the range of 0.006-0.060. Compared to KS for sodium chloride (NaCl) in the literature, KS values for (NH4)2SO4 are always higher for the same compound, suggesting a higher salting-out effect of (NH4)2SO4. A polyparameter linear free energy relationship (pp-LFER) for predicting KS in (NH4)2SO4 solutions was generated using the experimental data for calibration. pp-LFER predicted KS agreed well with measured KS reported in the literature. KS for (NH4)2SO4 was also predicted using the quantum-chemical COSMOtherm software and the thermodynamic model AIOMFAC. While COSMOtherm generally overpredicted the experimental KS, predicted and experimental values were correlated. Therefore, a fitting factor needs to be applied when using the current version of COSMOtherm to predict KS. AIOMFAC tends to underpredict the measured KS((NH4)2SO4) but always overpredicts KS(NaCl). The prediction error is generally larger for KS(NaCl) than for KS((NH4)2SO4). AIOMFAC also predicted a dependence of KS on the salt concentrations, which is not observed in the experimental data. In order to demonstrate that the models developed and calibrated in this study can be applied to estimate Setschenow coefficients for atmospherically relevant compounds involved in secondary organic aerosol formation based on chemical structure alone, we predicted and compared KS for selected

  14. Numerical simulation of solute transport in southwestern Salt Lake Valley, Utah

    USGS Publications Warehouse

    Lambert, P.M.

    1996-01-01

    Contaminated ground water characterized by high concentrations of dissolved solids and dissolved sulfate, and in areas, by low pH and elevated concentrations of metals, is present near public-supply wells in the southwestern Salt Lake Valley. To provide State officials and water users with information concerning the potential movement of contaminated ground water to points of withdrawal in the area, an analysis of solute transport using computer models was done by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water  Rights, and local municipalities and water users.A three-dimensional solute-transport model was developed and couples with an existing ground-water flow model of Salt Lake Valley to simulate the movement of dissolved sulfate in ground water in southwestern Salt Lake Valley. Development and calibration of the transport model focused mainly on sulfate movement down-gradient from the Bingham Creek Reservoirs and the South Jordan evaporation ponds east of the mouth of Bingham Canyon. Estimates of transport parameters were adjusted during a calibration simulation representing conditions during 1965-93. After calibration, the transport model was used to simulate future sulfate movement for 1994-2043.Because of uncertainty in estimated transport-parameter values, three projection transport simulations incorporating a range of probable parameter values were done to evaluate future sulfate movement and changes in sulfate concentrations at selected public-supply wells. These projection simulations produced a possible range of computed transport rates and patterns. In general, the projection simulations indicated movement of the sulfate plume east of the Bingham Creek reservoir toward public-supply wells northeast of the reservoirs and then eastward toward the Jordan River. Ground water with high concentrations of sulfate east of the South Jordan evaporation ponds is simulated as moving west to east under the

  15. Effect of Protein-Lipid-Salt Interactions on Sodium Availability in the Mouth and Consequent Perception of Saltiness: In Solutions.

    PubMed

    Yucel, Umut; Peterson, Devin G

    2015-09-02

    The influence of protein-sodium interactions on the availability of sodium in the aqueous phase of liquid samples and consequently on the perception of saltiness was investigated. The aqueous effluents of casein and casein emulsion-salt solutions were monitored for sodium availability from a tongue column system. In the aqueous protein-salt solutions, increasing the protein/salt ratio from 1:1 to 5:1 or 10:1 significantly decreased the initial salt concentration in the effluent and resulted in a higher salt concentration in the effluent over time. Sensory analysis was in agreement. Samples with increased protein were rated as having significantly lower initial saltiness and a higher salty aftertaste. However, when casein was formulated as an emulsion, the initial release of sodium in the effluent was enhanced (compared to nonemulsified protein). Increasing the emulsion interfacial area (more hydrophilic segments of the protein were structured into the aqueous phase) resulted in a higher salt concentration in the aqueous phase and greater perceived saltiness intensity. In summary, protein interactions, specifically ionic, were reported as food interactions that influence salt perception and provide a basis to develop higher flavor quality low-sodium food products.

  16. Water Uptake by Mars Salt Analogs: An Investigation of Stable Aqueous Solutions Using Raman Microscopy

    NASA Astrophysics Data System (ADS)

    Nuding, Danielle L.

    Liquid water processes that may occur on the surface and near-subsurface of Mars have important implications for the present-day water cycle, habitability, and planetary protection policies. The presence of salts on Mars plays a role in surface-atmosphere interactions as salts enhance the soil's ability to retain water. This thesis explores the phase transitions of water upon interaction with Mars relevant salt analogs. Water uptake and loss properties of a single and complex Mars analog are examined using a Raman microscope equipped with an environmental cell. The effect of the hygroscopic salts on bacterial spores was evaluated with a focus on potential terrestrial contamination on outbound spacecraft and its influence on planetary protection concerns. Calcium perchlorate (Ca(ClO4)2) is a highly deliquescent salt that may exist on the surface of present-day Mars. Here, we quantify the deliquescent relative humidity (DRH) and efflorescent relative humidity (ERH) of Ca(ClO4)2 as a function of temperature (223 K to 273 K) to elucidate its behavior on the surface of Mars. Mars relevant temperature and relative humidity (RH) conditions were simulated and deliquescence (solid to aqueous) and efflorescence (aqueous to solid) phase transitions of Ca(ClO4)2 were characterized. Experimental DRH values were compared to a thermodynamic model for three hydration states of Ca(ClO 4)2. Calcium perchlorate was found to supersaturate, with lower ERH values than DRH values. Additionally, we conducted a 17-hour experiment to simulate a subsurface relative humidity and temperature diurnal cycle. This demonstrated that aqueous Ca(ClO4)2 solutions can persist without efflorescing for the majority of a martian sol, up to 17 hours under Mars temperature heating rates and RH conditions. Applying these experimental results to martian surface and subsurface heat and mass transfer models, we find that aqueous Ca(ClO4)2 solutions could persist for most of the martian sol under present

  17. Silica Polymerization from Supersaturated Dilute Aqueous Solutions in the Presence of Alkaline Earth Salts.

    PubMed

    Kley, M; Kempter, A; Boyko, V; Huber, K

    2017-06-20

    The early stages of silica polymerization in aqueous solution proceed according to a mechanism based on three steps: nucleation, particle growth, and agglomeration of the particles. Application of time-resolved static and dynamic light scattering as a powerful in situ technique in combination with spectrophotometric analysis of the monomer consumption based on the molybdenum blue method was carried out to further investigate this 3-step process. Experiments were carried out at four different initial silicic acid contents covering a range between 350 and 750 ppm in the presence of either 10 mM NaCl or 5 mM of a mixture of CaCl2 and MgCl2. The process in all cases was initiated with a drop of pH to 7. Addition of the salts made possible an analysis of the impact of an electrolyte on the process. Independent of the presence or absence of salt, particle growth in step two proceeded as a monomer-addition process without being interfered significantly by Ostwald-ripening. The growing particles were compact with a homogeneous density. The size of the particles approached final values between 5 and 20 nm with the actual value increasing with decreasing initial silicic acid content. Above a certain concentration of initial silica content, which depends on the level of added salt, particle-particle interactions caused agglomeration. The presence of electrolyte shifted this level from ∼2000 ppm to a range between 500 and 750 ppm. The resulting agglomerates had a fractal dimension of 2. Independent of the conditions, particle growth could be described with a simple nucleation and growth model.

  18. Hydrology of the Bonneville Salt Flats, northwestern Utah, and simulation of ground-water flow and solute transport in the shallow-brine aquifer

    USGS Publications Warehouse

    Mason, James L.; Kipp, Kenneth L.

    1998-01-01

    This report describes the hydrologic system of the Bonneville Salt Flats with emphasis on the mechanisms of solute transport. Variable-density, three-dimensional computer simulations of the near-surface part of the ground-water system were done to quantify both the transport of salt dissolved in subsurface brine that leaves the salt-crust area and the salt dissolved and precipitated on the land surface. The study was designed to define the hydrology of the brine ground-water system and the natural and anthropogenic processes causing salt loss, and where feasible, to quantify these processes. Specific areas of study include the transport of salt in solution by ground-water flow and the transport of salt in solution by wind-driven ponds and the subsequent salt precipitation on the surface of the playa upon evaporation or seepage into the subsurface. In addition, hydraulic and chemical changes in the hydrologic system since previous studies were documented.

  19. Lysozyme-lysozyme and lysozyme-salt interactions in the aqueous saline solution: a new square-well potential.

    PubMed

    Chang, Bong Ho; Bae, Young Chan

    2003-01-01

    We investigate lysozyme-lysozyme and lysozyme-salt interactions in electrolyte solutions using a molecular-thermodynamic model. An equation of state based on the statistical mechanical perturbation theory is applied to describe the interactions. The perturbation term includes a new square-well potential of mean force, which implies the information about the lysozyme surface and salt type. The attractive energy of the potential of mean force is correlated with experimental cloud-point temperatures of lysozyme in various solution conditions. The same attractive energy is used to predict osmotic pressure of a given system with no additional parameters. The new potential shows a satisfactory improvement in understanding the interactions between lysozymes in aqueous salt solutions.

  20. Effect of Intravenously Administered Crystalloid Solutions on Acid-Base Balance in Domestic Animals.

    PubMed

    Muir, W

    2017-09-01

    Intravenous fluid therapy can alter plasma acid-base balance. The Stewart approach to acid-base balance is uniquely suited to identify and quantify the effects of the cationic and anionic constituents of crystalloid solutions on plasma pH. The plasma strong ion difference (SID) and weak acid concentrations are similar to those of the administered fluid, more so at higher administration rates and with larger volumes. A crystalloid's in vivo effects on plasma pH are described by 3 general rules: SID > [HCO3-] increases plasma pH (alkalosis); SID < [HCO3-] decreases plasma pH (alkalosis); and SID = [HCO3-] yields no change in plasma pH. The in vitro pH of commercially prepared crystalloid solutions has little to no effect on plasma pH because of their low titratable acidity. Appreciation of IV fluid composition and an understanding of basic physicochemical principles provide therapeutically valuable insights about how and why fluid therapy can produce and correct alterations of plasma acid-base equilibrium. The ideal balanced crystalloid should (1) contain species-specific concentrations of key electrolytes (Na(+) , Cl(-) , K(+) , Ca(++) , Mg(++) ), particularly Na(+) and Cl(-) ; (2) maintain or normalize acid-base balance (provide an appropriate SID); and (3) be isosmotic and isotonic (not induce inappropriate fluid shifts) with normal plasma. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  1. Hydrogen generation in microbial reverse-electrodialysis electrolysis cells using a heat-regenerated salt solution.

    PubMed

    Nam, Joo-Youn; Cusick, Roland D; Kim, Younggy; Logan, Bruce E

    2012-05-01

    Hydrogen gas can be electrochemically produced in microbial reverse-electrodialysis electrolysis cells (MRECs) using current derived from organic matter and salinity-gradient energy such as river water and seawater solutions. Here, it is shown that ammonium bicarbonate salts, which can be regenerated using low-temperature waste heat, can also produce sufficient voltage for hydrogen gas generation in an MREC. The maximum hydrogen production rate was 1.6 m(3) H(2)/m(3)·d, with a hydrogen yield of 3.4 mol H(2)/mol acetate at a salinity ratio of infinite. Energy recovery was 10% based on total energy applied with an energy efficiency of 22% based on the consumed energy in the reactor. The cathode overpotential was dependent on the catholyte (sodium bicarbonate) concentration, but not the salinity ratio, indicating high catholyte conductivity was essential for maximizing hydrogen production rates. The direction of the HC and LC flows (co- or counter-current) did not affect performance in terms of hydrogen gas volume, production rates, or stack voltages. These results show that the MREC can be successfully operated using ammonium bicarbonate salts that can be regenerated using conventional distillation technologies and waste heat making the MREC a useful method for hydrogen gas production from wastes.

  2. Isolation and characterization of coagulant extracted from Moringa oleifera seed by salt solution.

    PubMed

    Okuda, T; Baes, A U; Nishijima, W; Okada, M

    2001-02-01

    It is known that M. oleifera contains a natural coagulant in the seeds. In our previous research, the method using salt water to extract the active coagulation component from M. oleifera seeds was developed and compared with the conventional method using water. In this research, the active coagulation component was purified from a NaCl solution crude extract of Moringa oleifera seeds. The active component was isolated and purified from the crude extract through a sequence of steps that included salting-out by dialysis, removal of lipids and carbohydrates by homogenization with acetone, and anion exchange. Specific coagulation activity of the active material increased up to 34 times more than the crude extract after the ion exchange. The active component was not the same as that of water extract. The molecular weight was about 3000 Da. The Lowry method and the phenol-sulfuric acid method indicated that the active component was neither protein nor polysaccharide. The optimum pH of the purified active component for coagulation of turbidity was pH 8 and above. Different from the conventional water extracts, the active component can be used for waters with low turbidity without increase in the dissolved organic carbon concentration.

  3. Stabilizing Superionic-Conducting Structures via Mixed-Anion Solid Solutions of Monocarba- closo -borate Salts

    DOE PAGES

    Tang, Wan Si; Yoshida, Koji; Soloninin, Alexei V.; ...

    2016-09-01

    Solid lithium and sodium closo-polyborate-based salts are capable of superionic conductivities surpassing even liquid electrolytes, but often only at above-ambient temperatures where their entropically driven disordered phases become stabilized. Here we show by X-ray diffraction, quasielastic neutron scattering, differential scanning calorimetry, NMR, and AC impedance measurements that by introducing 'geometric frustration' via the mixing of two different closo-polyborate anions, namely, 1-CB9H10- and CB11H12-, to form solid-solution anion-alloy salts of lithium or sodium, we can successfully suppress the formation of possible ordered phases in favor of disordered, fast-ion-conducting alloy phases over a broad temperature range from subambient to high temperatures. Finally,more » this result exemplifies an important advancement for further improving on the remarkable conductive properties generally displayed by this class of materials and represents a practical strategy for creating tailored, ambient-temperature, solid, superionic conductors for a variety of upcoming all-solid-state energy devices of the future.« less

  4. Self-organization of poly(ethylene oxide) on the surface of aqueous salt solutions.

    PubMed

    Fuchs, Christian; Hussain, Hazrat; Amado, Elkin; Busse, Karsten; Kressler, Joerg

    2015-01-01

    It is demonstrated that stable Langmuir films of poly(ethylene oxide) (PEO) can be formed up to surface pressures of 30 mN m(-1) when potassium carbonate K2CO3 is added to the aqueous subphase. Generally, PEO homopolymer cannot stay on the water surface at a surface pressure ≥10 mN m(-1) due to its high water solubility. To prepare stable monolayer films, PEO can be modified with hydrophobic moieties. However, by exploiting the salting out effect by adding certain salts (K2CO3 or MgSO4) into the aqueous subphase, not only very stable films but also unusual self-organization can be achieved by the PEO homopolymer on the surface of the aqueous solution. Thus, a series of OH-terminated PEOs is found to form a stable monolayer at K2CO3 concentrations of 2 M and above in the aqueous subphase, and the stability of the film increases with an increase in K2CO3 concentration. Hysteresis experiments are also carried out. During the phase transition induced by progressive compression, self-organization into well-defined domains with sizes in the micrometer range are observed, and with further compression and holding of the film for 30 min and above the microdomains transform into a crystalline morphology as visualized by Brewster angle microscopy. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Results for the Fourth Quarter Calendar Year 2015 Tank 50H Salt Solution Sample

    SciTech Connect

    Crawford, C.

    2016-01-11

    In this memorandum, the chemical and radionuclide contaminant results from the Fourth Quarter Calendar Year 2015 (CY15) sample of Tank 50H salt solution are presented in tabulated form. The Fourth Quarter CY15 Tank 50H samples were obtained on October 29, 2015 and received at Savannah River National Laboratory (SRNL) on October 30, 2015. The information from this characterization will be used by Defense Waste Processing Facility (DWPF) & Saltstone Facility Engineering for the transfer of aqueous waste from Tank 50H to the Salt Feed Tank in the Saltstone Production Facility, where the waste will be treated and disposed of in the Saltstone Disposal Facility. This memorandum compares results, where applicable, to Saltstone Waste Acceptance Criteria (WAC) limits and targets. Data pertaining to the regulatory limits for Resource Conservation and Recovery Act (RCRA) metals will be documented at a later time per the Task Technical and Quality Assurance Plan (TTQAP) for the Tank 50H saltstone task. The chemical and radionuclide contaminant results from the characterization of the Fourth Quarter Calendar Year 2015 (CY15) sampling of Tank 50H were requested by SRR personnel and details of the testing are presented in the SRNL Task Technical and Quality Assurance Plan.

  6. Soluble aggregates in aqueous solutions of polyion-surfactant ion complex salts and a nonionic surfactant.

    PubMed

    Janiak, John; Tomšič, Matija; Lundberg, Dan; Olofsson, Gerd; Piculell, Lennart; Schillén, Karin

    2014-08-14

    Water-soluble aggregates based on two polyion-surfactant ion "complex salts", consisting of hexadecyltrimethylammonium (C16TA(+)) and polyacrylate (PA(-)) with either 25 or 6000 repeating units, with added nonionic surfactant octaethylene glycol monododecyl ether (C12E8) have been investigated. A previous phase study has shown that added C12E5 or C12E8 can solubilize complex salts in aqueous systems, and that increasing the poly(ethylene oxide) chain length of the nonionic surfactant and/or decreasing the polyion length favors dissolution. In this work we report on dynamic light scattering, NMR diffusometry, small-angle X-ray scattering, and isothermal titration calorimetry measurements performed to characterize the solubilized composite aggregates in dilute aqueous solution in terms of size and stoichiometry. It was found that mixed aggregates of polyacrylate, C16TA(+) ions, and C12E8, with almost constant stoichiometry, coexist with free micelles of C12E8 at all investigated mixing ratios. The length of the polyion only weakly affects the stoichiometry of the mixed aggregates while strongly affecting their size and water solubility.

  7. Effectiveness of oral rehydration salt solution (ORS) in reduction of death during cholera epidemic.

    PubMed

    Sircar, B K; Saha, M R; Deb, B C; Singh, P K; Pal, S C

    1990-01-01

    An extensive outbreak of acute gastroenteritis involving all age group of patients occurred during July-September, 1978 in the Central district of Manipur state. A total of 4469 cases occurred during the period. 45.7% of diarrhoea cases sampled and 47.6% of water samples collected from rivers were found to be positive for V.cholerae biotype EITor. Case fatality rate in this epidemic was exceptionally low (0.8%) which was attributed to the early domiciliary use of oral rehydration salt solution (ORS) in the affected villages. Utility of ORS in drastic reduction of case fatality rate during any epidemic situation was first of its kind in the Indian scene.

  8. Synthesis, Solution, and Structural Characterization of Tetrahydrofuranyl-2,2-Bisphosphonic Acid Disodium Salt

    PubMed Central

    Maltezou, Elena; Stylianou, Marios; Roy, Sudeshna; Drouza, Chryssoula; Keramidas, Anastasios D.

    2010-01-01

    Bisphosphonates are biologically relevant therapeutics for bone disorders and cancer. Reaction of γ-chlorobutyric acid, phosphorus acid, and phosphorus trichloride without the use of solvent gave the tetrahydrofuranyl-2,2-bisphosphonate sodium salt (Na2H2L). The Na2H2L was isolated, characterized in solution by 1H, 13C, and 31P NMR spectroscopy and in solid state by single X-Ray crystallography. The crystal structure showed that the Na2H2L forms in the crystal infinite two-dimensional sheets stacked one parallel to the other. A comparison of the chelating properties of H2L2− with similar hydroxyl bisphosphonate ligands shows that the strength of the Na–O(furanyl/hydroxyl) bond is directly related to the total charge of the ligand anion. PMID:20467558

  9. Electrophysical methods of separation of metal cations in the moving salts solution

    NASA Astrophysics Data System (ADS)

    Gofman, V. N.; Tuksov, I. V.; Timchenko, S. N.; Shamanin, I. V.; Poberezhnikov, A. D.; Kazaryan, M. A.

    2016-07-01

    The results of experiments on the excitation of the phenomenon of selective drift of solvated ions under the influence of an external "asymmetric" electric field to the circulating solution of calcium chloride and magnesium salts in a polar liquid dielectric - water are shown. The purpose of the experiments was to determine the influence of the field frequency and amplitude of the field strength on the excitation phenomenon, and the study of the operating characteristics of the testing apparatus - a dividing cell. The dependences of the separation efficiency of solvated cations from the frequency of the external field and the excitation threshold of the phenomenon from the field strength in the separation cell are defined.

  10. Effect of fluid resuscitation with balanced solutions on platelets: In vitro simulation of 20% volume substitution.

    PubMed

    Krzych, Łukasz J; Czempik, Piotr F

    2017-05-12

    Fluid resuscitation in massive bleeding may cause coagulation disorders by dilution of platelets and clotting factors or by the definite influence on theirfunction. The aim of this study was to investigate the effects of balanced crystalloid and colloid solutions on platelets (PLT) in vitro using complex assessment of coagulation. The study group was comprised of 32 American Society of Anesthesiologists physical status class I male volunteers, aged 21-35 (29 ± 4) years, weighting 59-103 (81.2 ± 9.8) kg. Whole blood samples were diluted at a 4:1 ratio with the following fluids: balanced crystalloid (Plasmalyte®), 6% hydroxyethyl starch 130/0.4 (Volulyte®) and succinylated gelatin (Geloplasma®). Coagulation was assessed using standard morphology, rotational thromboelastometry and aggregometry. Dilution with all fluids caused statistically significant drop in the number of platelets (p < 0.01) but the effect did not differ between solutions (p > 0.05 for all). Other platelet parameters, such as platelet distribution width, mean platelet volume and platelet-large cell ratio were not affected by the solutions. Haemodilution had no effect on platelet function (p = 0.1). Decreased platelet component of clot strength was found for all three fluids (p < 0.05), although the effect for colloids was more pronounced. The effect of balanced crystalloids and colloids on platelet aggregation was insignificant, even after 20% volume substitution with the resuscitation fluids.

  11. Microwave irradiation affects ion pairing in aqueous solutions of alkali halide salts

    NASA Astrophysics Data System (ADS)

    Mohorič, Tomaž; Bren, Urban

    2017-01-01

    Using the molecular dynamics simulations with separate thermostats for translational and rotational degrees of freedom, we investigate the effects of water's rotational motion on the ion pairing of ionic solutes in aqueous solutions. The situation with rotational temperature higher than the translational one, Trot>Ttrs , is mimicking the non-equilibrium effects of microwaves on model solutions of alkali halide salts. The simulations reveal that an increase in the rotational temperature at constant translational temperature exerts significant changes in the structure of the solution. The latter are reflected in increased pairing of the oppositely charged ions, which can be explained by the weaker ability of rotationally excited water to screen and separate the opposite charges. It seems that Collins' law of matching water affinities retains its validity also in the non-equilibrium situation where the rotational temperature exceeds the translational one. On the other hand, the equilibrium effect (i.e., an increase in the solution's overall temperature T ≡Trot = Ttrs) favors the formation of small-small (NaCl), while it has a little effect on large-large (CsI) ion pairs. This is in accordance with water becoming less polar solvent upon a temperature increase. Furthermore, we investigated the effects of excited translational motion of water (and ions) on the ion pairing by increasing the translational temperature, while keeping the rotational one unchanged (i.e., Ttrs>Trot ). Interestingly, in certain cases the faster translational motion causes an increase in correlations. The temperature variations in the like-ion association constants, Kas++ and Kas-, are also examined. Here the situation is more complex but, in most cases, a decrease in the ion pairing is observed.

  12. Additional disinfection with a modified salt solution in a root canal model.

    PubMed

    van der Waal, Suzette V; Oonk, Charlotte A M; Nieman, Selma H; Wesselink, Paul R; de Soet, Johannes J; Crielaard, Wim

    2015-10-01

    The aim of this study is to investigate the disinfecting properties of a modified salt solution (MSS) and calcium hydroxide (Ca(OH)2) in a non-direct-contact ex-vivo model. Seventy-four single-canal roots infected with Enterococcus faecalis were treated with 1% sodium hypochlorite (NaOCl) irrigation or with NaOCl irrigation with subsequent dressing with MSS or Ca(OH)2. After removal of the dressings, the roots were filled with bacterial growth medium and incubated for seven days to enable the surviving bacteria to repopulate the root canal lumen. Growth was determined by sampling the root canals with paper points before treatment (S1), after treatment (S2) and incubation after treatment (S3). The colony forming units were counted at S1 and S2. At S3, growth was determined as no/yes regrowth. The Kruskal-Wallis, McNemar and χ(2) test were used for statistical analyses. At S2, in the NaOCl group, growth was found in 5 of 19 root canals. After the removal of MSS or Ca(OH)2 bacteria were retrieved from one root canal in both groups. At S3, repopulation of the root canals had occurred in 14 of 19 roots after sole NaOCl irrigation, 6 of 20 roots after MSS-dressing and in 14 of 20 roots after Ca(OH)2-dressing. MSS was more effective in preventing regrowth than Ca(OH)2 (P=0.009). The modified salt solution prevented regrowth in roots which indicates that it can eliminate persistent bacteria. Dressing the root canals with Ca(OH)2 did not provide additional disinfection after NaOCl irrigation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Mechanical Behavior of Salt Caverns: Closed-Form Solutions vs Numerical Computations

    NASA Astrophysics Data System (ADS)

    Wang, Linlin; Bérest, Pierre; Brouard, Benoît

    2015-11-01

    Creep closure and structural stability of a cylindrical elongated cavern leached out from a salt formation are discussed. The Norton-Hoff creep law, or "power law", is used to capture the main features of salt rheological behavior. Two failure criteria are considered: (1) shear stresses must not be larger than a certain fraction of the mean stress (dilation criterion); and (2) the effective stress at the cavern wall (actual stress plus cavern fluid pressure) must not be tensile. The case of a brine-filled cavern whose pressure is kept constant is discussed first. It is proved that creep closure reaches a steady state such that stresses in the rock mass remain constant. However, decades are needed to reach such a state. During the transient phase that results from the slow redistribution of stresses in the rock mass, deviatoric stresses decrease at the vicinity of the cavern wall, and onset of dilation is less and less likely. At this point, the case of a rapid brine pressure increase, typical of a tightness test, is considered. It is proved that during such a swift pressure increase, cavern behavior is almost perfectly elastic; there is no risk of dilation onset. However, even when cavern pressure remains significantly smaller than geostatic, the effective stress at cavern wall can become tensile. These results, obtained through numerical computations, are confirmed by closed-form solutions obtained in the case of an idealized perfectly cylindrical cavern; these solutions provide a better insight into the main structural features of the behavior of the cavern.

  14. Estimating diffusivity from the mixed layer heat and salt balances in the North Pacific

    NASA Astrophysics Data System (ADS)

    Cronin, M. F.; Pelland, N.; Emerson, S. R.; Crawford, W. R.

    2015-12-01

    Data from two National Oceanographic and Atmospheric Administration (NOAA) surface moorings in the North Pacific, in combination with data from satellite, Argo floats and glider (when available), are used to evaluate the residual diffusive flux of heat across the base of the mixed layer from the surface mixed layer heat budget. The diffusion coefficient (i.e., diffusivity) is then computed by dividing the diffusive flux by the temperature gradient in the 20-m transition layer just below the base of the mixed layer. At Station Papa in the NE Pacific subpolar gyre, this diffusivity is 1×10-4 m2/s during summer, increasing to ~3×10-4 m2/s during fall. During late winter and early spring, diffusivity has large errors. At other times, diffusivity computed from the mixed layer salt budget at Papa correlate with those from the heat budget, giving confidence that the results are robust for all seasons except late winter-early spring and can be used for other tracers. In comparison, at the Kuroshio Extension Observatory (KEO) in the NW Pacific subtropical recirculation gyre, somewhat larger diffusivity are found based upon the mixed layer heat budget: ~ 3×10-4 m2/s during the warm season and more than an order of magnitude larger during the winter, although again, wintertime errors are large. These larger values at KEO appear to be due to the increased turbulence associated with the summertime typhoons, and weaker wintertime stratification.

  15. Estimating diffusivity from the mixed layer heat and salt balances in the North Pacific

    NASA Astrophysics Data System (ADS)

    Cronin, Meghan F.; Pelland, Noel A.; Emerson, Steven R.; Crawford, William R.

    2015-11-01

    Data from two National Oceanographic and Atmospheric Administration (NOAA) surface moorings in the North Pacific, in combination with data from satellite, Argo floats and glider (when available), are used to evaluate the residual diffusive flux of heat across the base of the mixed layer from the surface mixed layer heat budget. The diffusion coefficient (i.e., diffusivity) is then computed by dividing the diffusive flux by the temperature gradient in the 20 m transition layer just below the base of the mixed layer. At Station Papa in the NE Pacific subpolar gyre, this diffusivity is 1 × 10-4 m2/s during summer, increasing to ˜3 × 10-4 m2/s during fall. During late winter and early spring, diffusivity has large errors. At other times, diffusivity computed from the mixed layer salt budget at Papa correlate with those from the heat budget, giving confidence that the results are robust for all seasons except late winter-early spring and can be used for other tracers. In comparison, at the Kuroshio Extension Observatory (KEO) in the NW Pacific subtropical recirculation gyre, somewhat larger diffusivities are found based upon the mixed layer heat budget: ˜ 3 × 10-4 m2/s during the warm season and more than an order of magnitude larger during the winter, although again, wintertime errors are large. These larger values at KEO appear to be due to the increased turbulence associated with the summertime typhoons, and weaker wintertime stratification.

  16. Effects of high calcium diet on arterial smooth muscle function and electrolyte balance in mineralocorticoid-salt hypertensive rats.

    PubMed

    Arvola, P; Ruskoaho, H; Pörsti, I

    1993-04-01

    1. The effects of a high calcium diet (2.5%) on blood pressure, electrolyte balance, plasma and tissue atrial natriuretic peptide (ANP), cytosolic free Ca2+ concentration ([Ca2+]i), and arterial smooth muscle responses were studied in one-kidney deoxycorticosterone (DOC)-NaCl hypertensive Wistar rats. 2. Calcium supplementation for 8 weeks markedly attenuated the development of DOC-NaCl hypertension and the associated cardiac hypertrophy, and prevented the DOC-NaCl-induced sodium-volume retention as judged by reduced plasma Na+, and decreased plasma and ventricular ANP concentrations in high calcium-fed DOC-NaCl rats. However, calcium supplementation did not affect the DOC-NaCl-induced rise in platelet [Ca2+]i. 3. Smooth muscle contractions of isolated mesenteric arterial rings in response to depolarization by K+ (20-30 mM) were enhanced in DOC-NaCl-treated rats, this enhancement being abolished by concurrent oral calcium loading. The Ca2+ entry blocker nifedipine (10 nM) inhibited the contractions induced by K+ (30-125 mM) more effectively in DOC-NaCl rats than in controls, while the inhibition in calcium-loaded DOC-NaCl rats was significantly greater than in controls only with 30 mM K+. 4. The contractions of mesenteric arterial rings induced by omission of K+ from the organ baths were used to evaluate cell membrane permeability to ions. In chemically denervated rings the onset of the gradual rise in contractile force in K(+)-free medium occurred earlier, and the rate of the contraction was faster in DOC-NaCl-treated rats than in controls and high calcium-fed DOC-NaCl rats. Smooth muscle relaxation induced by 0.5 mM K+ upon K(+)-free contractions was clearly slower in DOC-NaCl rats than in controls and calcium-supplemented DOC-NaCl rats. 5. The functions of arterial smooth muscle Na+, Ca2+ exchange and Ca(2+)-ATPase were evaluated by the aortic contractions elicited by low Na+ medium, and the subsequent relaxation responses induced by Ca(2+)-free solution (in the

  17. Complex electronic waste treatment - An effective process to selectively recover copper with solutions containing different ammonium salts.

    PubMed

    Sun, Z H I; Xiao, Y; Sietsma, J; Agterhuis, H; Yang, Y

    2016-11-01

    Recovery of valuable metals from electronic waste has been highlighted by the EU directives. The difficulties for recycling are induced by the high complexity of such waste. In this research, copper could be selectively recovered using an ammonia-based process, from industrially processed information and communication technology (ICT) waste with high complexity. A detailed understanding on the role of ammonium salt was focused during both stages of leaching copper into a solution and the subsequent step for copper recovery from the solution. By comparing the reactivity of the leaching solution with different ammonium salts, their physiochemical behaviour as well as the leaching efficiency could be identified. The copper recovery rate could reach 95% with ammonium carbonate as the leaching salt. In the stage of copper recovery from the solution, electrodeposition was introduced without an additional solvent extraction step and the electrochemical behaviour of the solution was figured out. With a careful control of the electrodeposition conditions, the current efficiency could be improved to be 80-90% depending on the ammonia salts and high purity copper (99.9wt.%). This research provides basis for improving the recyclability and efficiency of copper recovery from such electronic waste and the whole process design for copper recycling. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Release of gaseous bromine from the photolysis of nitrate and hydrogen peroxide in simulated sea-salt solutions

    NASA Astrophysics Data System (ADS)

    George, Ingrid J.; Anastasio, Cort

    We have carried out a series of laboratory experiments to investigate the oxidation of bromide (Br -) by hydroxyl radical ( rad OH) in solutions used to mimic sea-salt particles. Aqueous halide solutions with nitrate or hydrogen peroxide (HOOH) as a photochemical source of rad OH were illuminated with 313 nm light and the resulting gaseous bromine (Br*(g)) was collected. While illumination of these solutions nearly always formed gaseous bromine (predominantly Br 2 based on modeling results), there was no evidence for the release of gaseous chlorine. The rate of Br*(g) release increased (up to a plateau value) with increasing concentrations of bromide and was enhanced at lower pH values for both nitrate and HOOH solutions. Increased ionic strength in nitrate solutions inhibited Br*(g) release and the extent of inhibition was dependent upon the salt used. In HOOH solutions, however, no ionic strength effects were observed and the presence of Cl - strongly enhanced Br*(g) release. Overall, for conditions typical of aged, deliquesced, sea-salt particles, the efficiencies of gaseous bromine release, expressed as mole of Br*(g) released per mole of rad OH photochemically formed, were typically 20-30%. Using these reaction efficiencies, we calculated the Br 2(g) release rate from aged, ambient sea-salt particles due to rad OH oxidation to be approximately 0.07 pptv h -1 with the main contributions from nitrate photolysis and partitioning of gas-phase rad OH into the particle. While our solution conditions are simplified compared to ambient particles, this estimated rate of Br 2 release is high enough to suggest that rad OH-mediated reactions in sea-salt particles could be a significant source of reactive bromine to the marine boundary layer.

  19. Excellent dynamic stability under saturated salt solution for aqueous quantum dots capped by multi-branched ligands

    NASA Astrophysics Data System (ADS)

    Xu, Jingkun; Xu, Shuhong; Lv, Changgui; Wang, Chunlei; Cui, Yiping

    2016-09-01

    Preparing quantum dots (QDs) with strong stability against salts is extremely important in some environments with ultrahigh salts concentration, such as the oil exploitation, wastewater treatment and biological markers. In this paper, we reported a simple new method to prepared highly stable QDs by using multi-branched ligands. Our results suggested that multi-branched ligands-capped QDs have extremely good dynamic stability even in salt-saturated solution. Unlike to traditional dynamic stability theory, which considers the electrostatic repulsion of QDs dominant QD stability, the current work found a new determined factor: the steric hindrance of ligand structure. The high steric hindrance effect of multi-branched ligands can maintain the single dispersity of QDs even at extremely low electrostatic repulsion. As a result, QDs with ultrahigh stability against salts can be realized.

  20. Impact of pressure, salt concentration, and temperature on the convective dissolution of carbon dioxide in aqueous solutions.

    PubMed

    Loodts, V; Rongy, L; De Wit, A

    2014-12-01

    The convective dissolution of carbon dioxide (CO2) in salted water is theoretically studied to determine how parameters such as CO2 pressure, salt concentration, and temperature impact the short-time characteristics of the buoyancy-driven instability. On the basis of a parameter-free dimensionless model, we perform a linear stability analysis of the time-dependent concentration profiles of CO2 diffusing into the aqueous solution. We explicit the procedure to transform the predicted dimensionless growth rate and wavelength of the convective pattern into dimensional ones for typical laboratory-scale experiments in conditions close to room temperature and atmospheric pressure. This allows to investigate the implicit influence of the experimental parameters on the characteristic length and time scales of the instability. We predict that increasing CO2 pressure, or decreasing salt concentration or temperature destabilizes the system with regard to convection, leading to a faster dissolution of CO2 into salted water.

  1. Numerical Simulation of the Freeze-Thaw Behavior of Mortar Containing Deicing Salt Solution.

    PubMed

    Esmaeeli, Hadi S; Farnam, Yaghoob; Bentz, Dale P; Zavattieri, Pablo D; Weiss, Jason

    2017-02-01

    This paper presents a one-dimensional finite difference model that is developed to describe the freeze-thaw behavior of an air-entrained mortar containing deicing salt solution. A phenomenological model is used to predict the temperature and the heat flow for mortar specimens during cooling and heating. Phase transformations associated with the freezing/melting of water/ice or transition of the eutectic solution from liquid to solid are included in this phenomenological model. The lever rule is used to calculate the quantity of solution that undergoes the phase transformation, thereby simulating the energy released/absorbed during phase transformation. Undercooling and pore size effects are considered in the numerical model. To investigate the effect of pore size distribution, this distribution is considered using the Gibbs-Thomson equation in a saturated mortar specimen. For an air-entrained mortar, the impact of considering pore size (and curvature) on freezing was relatively insignificant; however the impact of pore size is much more significant during melting. The fluid inside pores smaller than 5 nm (i.e., gel pores) has a relatively small contribution in the macroscopic freeze-thaw behavior of mortar specimens within the temperature range used in this study (i.e., +24 °C to -35 °C), and can therefore be neglected for the macroscopic freeze-thaw simulations. A heat sink term is utilized to simulate the heat dissipation during phase transformations. Data from experiments performed using a low-temperature longitudinal guarded comparative calorimeter (LGCC) on mortar specimens fully saturated with various concentration NaCl solutions or partially saturated with water is compared to the numerical results and a promising agreement is generally obtained.

  2. Reduction of earth alkaline metal salts in THF solution studied by picosecond pulse radiolysis.

    PubMed

    Ma, Jun; Archirel, Pierre; Schmidhammer, Uli; Teuler, Jean-Marie; Pernot, Pascal; Mostafavi, Mehran

    2013-12-27

    Picosecond pulse radiolysis of tetrahydrofuran (THF) solutions containing earth alkaline metal salt, M(II)(ClO4)2, at different concentrations are performed using two different supercontinua as probe pulse, one covering the visible and another the near-infrared (NIR) down to the visible. Two types of line scan detectors are used to record the absorption spectra in the range from 400 to 1500 nm. Because of the strong overlap between the spectra of the absorbing species in the present wavelength range, global matrices were built for each M(II) system, by delay-wise binding the matrix for pure THF with the available matrices for this cation. The number of absorbers was assessed by Singular Value Decomposition of the global matrix, and a MCR-ALS analysis with the corresponding number of species was performed. The analysis of the results show clearly that solvated electron reacts with the earth alkaline metal molecule and the product has an optical absorption band very different than that of solvated electron in pure THF. So, contrarily to the case of solution containing free Na(+), in the presence of Mg(II), Ca(II) and Sr(II) the observed absorption band is not only blueshifted, but its shape is also drastically changed. In fact with Na(+) solvated electron forms a tight-contact pair but with earth alkaline metal cation solvated electron is scavenged by the undissociated molecule M(II)(ClO4)2. In order to determine the structure of the absorbing species observed after the electron pulse, Monte Carlo/DFT simulations were performed in the case of Mg(II), based on a classical Monte Carlo code and DFT/PCM calculation of the solute. The UV-visible spectrum of the solute is calculated with the help of the TDDFT method. The calculated spectrum is close to the experimental one. It is due to two species, a contact pair and an anion.

  3. Seaglider surveys at Ocean Station Papa: Diagnosis of upper-ocean heat and salt balances using least squares with inequality constraints

    NASA Astrophysics Data System (ADS)

    Pelland, Noel A.; Eriksen, Charles C.; Cronin, Meghan F.

    2017-06-01

    Heat and salt balances in the upper 200 m are examined using data from Seaglider spatial surveys June 2008 to January 2010 surrounding a NOAA surface mooring at Ocean Station Papa (OSP; 50°N, 145°W). A least-squares approach is applied to repeat Seaglider survey and moored measurements to solve for unknown or uncertain monthly three-dimensional circulation and vertical diffusivity. Within the surface boundary layer, the estimated heat and salt balances are dominated throughout the surveys by turbulent flux, vertical advection, and for heat, radiative absorption. When vertically integrated balances are considered, an estimated upwelling of cool water balances the net surface input of heat, while the corresponding large import of salt across the halocline due to upwelling and diffusion is balanced by surface moisture input and horizontal import of fresh water. Measurement of horizontal gradients allows the estimation of unresolved vertical terms over more than one annual cycle; diffusivity in the upper-ocean transition layer decreases rapidly to the depth of the maximum near-surface stratification in all months, with weak seasonal modulation in the rate of decrease and profile amplitude. Vertical velocity is estimated to be on average upward but with important monthly variations. Results support and expand existing evidence concerning the importance of horizontal advection in the balances of heat and salt in the Gulf of Alaska, highlight time and depth variability in difficult-to-measure vertical transports in the upper ocean, and suggest avenues of further study in future observational work at OSP.

  4. Balancing

    NASA Astrophysics Data System (ADS)

    Harteveld, Casper

    At many occasions we are asked to achieve a “balance” in our lives: when it comes, for example, to work and food. Balancing is crucial in game design as well as many have pointed out. In games with a meaningful purpose, however, balancing is remarkably different. It involves the balancing of three different worlds, the worlds of Reality, Meaning, and Play. From the experience of designing Levee Patroller, I observed that different types of tensions can come into existence that require balancing. It is possible to conceive of within-worlds dilemmas, between-worlds dilemmas, and trilemmas. The first, the within-world dilemmas, only take place within one of the worlds. We can think, for example, of a user interface problem which just relates to the world of Play. The second, the between-worlds dilemmas, have to do with a tension in which two worlds are predominantly involved. Choosing between a cartoon or a realistic style concerns, for instance, a tension between Reality and Play. Finally, the trilemmas are those in which all three worlds play an important role. For each of the types of tensions, I will give in this level a concrete example from the development of Levee Patroller. Although these examples come from just one game, I think the examples can be exemplary for other game development projects as they may represent stereotypical tensions. Therefore, to achieve harmony in any of these forthcoming games, it is worthwhile to study the struggles we had to deal with.

  5. Preparation of Some Homologous TEMPO Nitroxides and Oxoammonium Salts; Notes on the NMR Spectroscopy of Nitroxide Free Radicals; Observed Radical Nature of Oxoammonium Salt Solutions Containing Trace Amounts of Corresponding Nitroxides in an Equilibrium Relationship.

    PubMed

    Bobbitt, James M; Eddy, Nicholas A; Cady, Clyde X; Jin, Jing; Gascon, Jose A; Gelpí-Dominguez, Svetlana; Zakrzewski, Jerzy; Morton, Martha D

    2017-09-06

    Three new homologous TEMPO oxoammonium salts and three homologous nitroxide radicals have been prepared and characterized. The oxidation properties of the salts have been explored. The direct (13)C NMR and EPR spectra of the nitroxide free radicals and the oxoammonium salts, along with TEMPO and its oxoammonium salt, have been successfully measured with little peak broadening of the NMR signals. In the spectra of all ten compounds (nitroxides and corresponding oxoammonium salts), the carbons in the 2,2,6,6-tetramethylpiperidine core do not appear, implying paramagnetic properties. This unpredicted overall paramagnetism in the oxoammonium salt solutions is explained by a redox equilibrium as shown between oxoammonium salts and trace amounts of corresponding nitroxide. This equilibrium is confirmed by electron interchange reactions between nitroxides with an N-acetyl substituent and oxoammonium salts with longer acyl side chains.

  6. Dietary potassium and the renal control of salt balance and blood pressure.

    PubMed

    Penton, David; Czogalla, Jan; Loffing, Johannes

    2015-03-01

    Dietary potassium (K(+)) intake has antihypertensive effects, prevents strokes, and improves cardiovascular outcomes. The underlying mechanism for these beneficial effects of high K(+) diets may include vasodilation, enhanced urine flow, reduced renal renin release, and negative sodium (Na(+)) balance. Indeed, several studies demonstrate that dietary K(+) intake induces renal Na(+) loss despite elevated plasma aldosterone. This review briefly highlights the epidemiological and experimental evidences for the effects of dietary K(+) on arterial blood pressure. It discusses the pivotal role of the renal distal tubule for the regulation of urinary K(+) and Na(+) excretion and blood pressure and highlights that it depends on the coordinated interaction of different nephron portions, epithelial cell types, and various ion channels, transporters, and ATPases. Moreover, we discuss the relevance of aldosterone and aldosterone-independent factors in mediating the effects of an altered K(+) intake on renal K(+) and Na(+) handling. Particular focus is given to findings suggesting that an aldosterone-independent downregulation of the thiazide-sensitive NaCl cotransporter significantly contributes to the natriuretic and antihypertensive effect of a K(+)-rich diet. Last but not least, we refer to the complex signaling pathways enabling the kidney to adapt its function to the homeostatic needs in response to an altered K(+) intake. Future work will have to further address the underlying cellular and molecular mechanism and to elucidate, among others, how an altered dietary K(+) intake is sensed and how this signal is transmitted to the different epithelial cells lining the distal tubule.

  7. [The water-salt balance and renal function in space flights and in model experiments].

    PubMed

    Morukov, B V; Noskov, V B; Larina, I M; Natochin, Iu V

    2003-03-01

    Study of a condition of mineral and water-electrolyte metabolism, function of kidneys, and their hormonal regulation during model experiments (hypokinesia, bed rest, immersion etc.), and also in space flights and in readaptation period, has shown a major role of water-electrolyte homeostasis during general adaptation of humans and animals to new conditions of life and to conditions of weightlessness in particular. The change in regulation of volumes of fluid milieu in an initial period of weightlessness was shown to be the consequence of redistribution of blood and hemodynamics of the shifts resulting in change of production of volume-regulation hormones, formation of negative water balance, and redistribution of fluid in the organism among various fluid compartments. At later stages of flight or long-term hypokinesia, a change of water-electrolyte homeostasis occurs with a decrease in the kidneys excretion of sodium, and diuresis, but with an increased excretion of calcium and production of ADH and RAAS hormones. Following returning to earth gravitation, the majority of astronauts have adaptive reactions, compensating for the loss extracellular fluid and mineral substances and formation of "earth" water-electrolyte homeostasis. For estimation of water-electrolyte homeostasis and the functions of kidneys in astronauts, various functional loading tests have been developed. The developed system of preventive maintenance is successfully used for abolition of adverse changes at various stages of space flight and in readaptation period.

  8. Water and salt balance of well-trained swimmers in training.

    PubMed

    Maughan, Ronald J; Dargavel, Lisa A; Hares, Rachael; Shirreffs, Susan M

    2009-12-01

    This study investigated fluid and electrolyte balance in well-trained male and female swimmers during 2 training sessions. Participants were 17 nationally ranked swimmers measured during a period of intensive training. Sweat loss was assessed from changes in body mass after correction for fluid intake and urine collection. Sweat composition was measured from waterproof absorbent patches applied at 4 skin sites. Air and pool-water temperatures were 36 degrees C and 27.4 degrees C, respectively. Training lasted 105 min in each session. All measured variables were similar on the 2 testing days. Mean sweat-volume loss was 548 +/- 243 ml, and mean sweat rate was 0.31 +/- 0.1 L/hr. Mean fluid intake was 489 +/- 270 ml. Mean body-mass loss was 0.10 0.50 kg, equivalent to 0.1% +/- 0.7% dehydration. Mean pretraining urine osmolality was 662 +/- 222 mOsm/kg, which was negatively associated with both mean drink volume consumed (p = .044, r = .244) and mean urine volume produced during training (p = .002, r2 = .468). Mean sweat Na+, K+, and Cl- concentrations (mmol/L) were 43 +/- 14, 4 +/- 1, and 31 +/- 9, respectively; values were not different between males and females and were not different between days except for a marginal difference in K+ concentration. The average swimmer remained hydrated during the session, and calculated sweat rates were similar to those in previous aquatic studies.

  9. Cryochemical method for forming spherical metal oxide particles from metal salt solutions

    DOEpatents

    Tinkle, M.C.

    1973-12-01

    A method is described of preparing small metal oxide spheres cryochemically utilizing metal salts (e.g., nitrates) that cannot readily be dried and calcined without loss of sphericity of the particles. Such metal salts are cryochemically formed into small spheres, partially or completely converted to an insoluble salt, and dried and calcined. (Official Gazette)

  10. Comparison of the effect of hormones on the hormone synthesis of Tetrahymena in medium or salt solution.

    PubMed

    Csaba, G; Lajkó, Eszter; Pállinger, Eva

    2010-11-01

    Tetrahymena pyriformis was maintained in TYM (tryptone-yeast medium) as well as in Losina salt solution. One hour treatment of 10⁻¹⁵ M histamine, serotonin or insulin was given before the histamine, serotonin, triiodothyronine and adrenocorticotropin contents of the cells were measured by flow cytometry after immunocytochemical staining. Maintenance in salt solution increased the hormone level in the cells, and use of the treatment hormone treatments further increased the endogenous hormone content relative to that in medium. The cells in salt mimic better the natural conditions, which means that the effects of hormones under more natural conditions are expressed to a greater extent than the exogenously given hormones in TYM typically used under laboratory conditions. Intercellular hormonal communication between the cells of a Tetrahymena population might assist in the survival of the individual cells.

  11. Adaptive resolution simulation of an atomistic DNA molecule in MARTINI salt solution

    NASA Astrophysics Data System (ADS)

    Zavadlav, J.; Podgornik, R.; Melo, M. N.; Marrink, S. J.; Praprotnik, M.

    2016-10-01

    We present a dual-resolution model of a deoxyribonucleic acid (DNA) molecule in a bathing solution, where we concurrently couple atomistic bundled water and ions with the coarse-grained MARTINI model of the solvent. We use our fine-grained salt solution model as a solvent in the inner shell surrounding the DNA molecule, whereas the solvent in the outer shell is modeled by the coarse-grained model. The solvent entities can exchange between the two domains and adapt their resolution accordingly. We critically asses the performance of our multiscale model in adaptive resolution simulations of an infinitely long DNA molecule, focusing on the structural characteristics of the solvent around DNA. Our analysis shows that the adaptive resolution scheme does not produce any noticeable artifacts in comparison to a reference system simulated in full detail. The effect of using a bundled-SPC model, required for multiscaling, compared to the standard free SPC model is also evaluated. Our multiscale approach opens the way for large scale applications of DNA and other biomolecules which require a large solvent reservoir to avoid boundary effects.

  12. Effect of Salt on the Uranyl Binding with Carbonate and Calcium Ions in Aqueous Solutions.

    PubMed

    Li, Bo; Zhou, Jingwei; Priest, Chad; Jiang, De-En

    2017-08-31

    The Ca2(UO2)(CO3)3 complex has been shown to be the dominant species of uranyl in different aqueous environments, and thermodynamic data of the complexation have been measured accurately recently. However, a detailed understanding of the binding processes with explicit consideration of the water molecules in the presence of common salt ions such as Na(+) and Cl(-) has been lacking. Here we use classical molecular dynamics combined with umbrella sampling to map the complete binding processes and their free-energy profiles leading to formation of the Ca2(UO2)(CO3)3 complex from UO2(2+), CO3(2-), and Ca(2+) in an aqueous NaCl solution to simulate the seawater conditions. We find that the presence of Na(+) ions affects the binding between UO2(2+) and CO3(2-) as well as between [(UO2)(CO3)3](4-) and Ca(2+) by changing the coordination mode of carbonate to UO2(2+). The free energies of binding from our simulations are in good agreement with the experimental data for both pure water and the NaCl solution. Our work shows that free-energy simulations based on classical molecular dynamics simulations can be a useful tool to examine the atomistic process of the ligand binding to form the Ca2(UO2)(CO3)3 complex under different aqueous environments and that the presence of common ions can impact the complexation chemistry of uranyl.

  13. Thermodynamic instability in supersaturated lysozyme solutions: Effect of salt and role of concentration fluctuations

    NASA Astrophysics Data System (ADS)

    Manno, Mauro; Xiao, Caide; Bulone, Donatella; Martorana, Vincenzo; San Biagio, Pier Luigi

    2003-07-01

    Experimental and theoretical work has suggested that protein crystal nucleation can be affected by the separation of two metastable liquid phases with different local concentrations, or more specifically by critical density fluctuations. We measure the amplitude and correlation length of local concentration fluctuations by light scattering for supersaturated solutions of hen egg-white lysozyme (at pH 4.5 and at different NaCl concentrations, up to 7% w/v). By extrapolating the critical divergent behavior of concentration fluctuation amplitude versus temperature, we determine the spinodal line, that is the limit of stability. Cloud-point measurements are used to determine liquid-liquid coexistence, consistent with previous work. In the present work, which is an extensive study of off-critical fluctuations in supersaturated protein solution, we observe a nonclassical scaling divergent behavior of the correlation length of concentration fluctuations, thus suggesting that off-critical fluctuations may have a role in crystallization kinetics. To appropriately fit the spinodal data, an entropic term must be added to the van der Waals or to the adhesive hard-sphere model. We interpret this contribution as due to the salt-induced modulation of protein hydration.

  14. Thermodynamic instability in supersaturated lysozyme solutions: effect of salt and role of concentration fluctuations.

    PubMed

    Manno, Mauro; Xiao, Caide; Bulone, Donatella; Martorana, Vincenzo; San Biagio, Pier Luigi

    2003-07-01

    Experimental and theoretical work has suggested that protein crystal nucleation can be affected by the separation of two metastable liquid phases with different local concentrations, or more specifically by critical density fluctuations. We measure the amplitude and correlation length of local concentration fluctuations by light scattering for supersaturated solutions of hen egg-white lysozyme (at pH 4.5 and at different NaCl concentrations, up to 7% w/v). By extrapolating the critical divergent behavior of concentration fluctuation amplitude versus temperature, we determine the spinodal line, that is the limit of stability. Cloud-point measurements are used to determine liquid-liquid coexistence, consistent with previous work. In the present work, which is an extensive study of off-critical fluctuations in supersaturated protein solution, we observe a nonclassical scaling divergent behavior of the correlation length of concentration fluctuations, thus suggesting that off-critical fluctuations may have a role in crystallization kinetics. To appropriately fit the spinodal data, an entropic term must be added to the van der Waals or to the adhesive hard-sphere model. We interpret this contribution as due to the salt-induced modulation of protein hydration.

  15. Dilute solution properties of Prunus armeniaca gum exudates: Influence of temperature, salt, and sugar.

    PubMed

    Fathi, Morteza; Mohebbi, Mohebbat; Koocheki, Arash; Hesarinejad, Mohammad Ali

    2017-03-01

    The aim of the current paper was to investigate the effect of different temperatures, salts and sugars on dilute solution properties of Prunus armeniaca gum exudates (PAGE) as a starting point to evaluate the potential utilization of this novel source of hydrocolloids in food and pharmaceutical systems. Berry number and the slope of master curve indicated that PAGE samples in all evaluated conditions were in dilute domain without coil overlapping and entanglement. Furthermore, the slope power law model also demonstrated that the molecular conformation of PAGE in all tested temperatures was close to rode-like. On the other hand, PAGE samples had random coil conformation in the presence of sugars and ions studied. Activation energy and chain flexibility of PAGE were found to be 0.83×10(7) (J/kg) and 997.3, respectively. This result revealed that temperature has a slight effect on intrinsic viscosity of PAGE solution, implying this gum can be introduced as a promising ingredient in food formulation that need to high stability against temperature. The data obtained in the present study and results thereof can be useful when considering the effect of additives generally used in food products and/or processing parameters like temperature in food systems. Copyright © 2016. Published by Elsevier B.V.

  16. Surface-induced liquid-gas transition in salt-free solutions of model charged colloids.

    PubMed

    Budkov, Yu A; Frolov, A I; Kiselev, M G; Brilliantov, N V

    2013-11-21

    We report a novel phenomenon of a surface-induced phase transition in salt-free solutions of charged colloids. We develop a theory of this effect and confirm it by Molecular Dynamics simulations. To describe the colloidal solution we apply a primitive model of electrolyte with a strong asymmetry of charge and size of the constituent particles - macroions and counterions. To quantify interactions of the colloidal particles with the neutral substrate we use a short-range potential which models dispersion van der Waals forces. These forces cause the attraction of colloids to the surface. We show that for high temperatures and weak attraction, only gradual increase of the macroion concentration in the near-surface layer is observed with increase of interaction strength. If however temperature drops below some threshold value, a new dense (liquid) phase is formed in the near-surface layer. It can be interpreted as a surface-induced first-order phase transition with a critical point. Using an appropriately adopted Maxwell construction, we find the binodal. Interestingly, the observed near-surface phase transition can occur at the absence of the bulk phase transition and may be seemingly classified as prewetting transition. The reported effect could be important for various technological applications where formation of colloidal particle layers with the desired properties is needed.

  17. Pointwise time asymptotic behavior of solutions to a general class of hyperbolic balance laws

    NASA Astrophysics Data System (ADS)

    Zeng, Yanni; Chen, Jiao

    2016-04-01

    In this paper we are interested in a general class of hyperbolic balance laws. Within the frame work of existence of a convex entropy function that symmetrizes the system in certain sense and the Kawashima-Shizuta condition, we study the large time behavior of the solution to the Cauchy problem in one space dimension. For a solution around a constant equilibrium state, we predetermine the asymptotic solution as a superposition of the constant state and diffusion waves along the equilibrium characteristic directions. We estimate the remainder in the pointwise sense both in space and in time. The decay rates in various directions are optimal, which further give the optimal Lp rates with 1 ≤ p ≤ ∞. Applications to several examples including the Kerr-Debye model are given.

  18. Synthesis and Application of Organic Phosphonate Salts as Draw Solutes in Forward Osmosis for Oil-Water Separation.

    PubMed

    Long, Qingwu; Shen, Liang; Chen, Rongbiao; Huang, Jiaqi; Xiong, Shu; Wang, Yan

    2016-11-01

    The development of suitable draw solution in forward osmosis (FO) process has attracted the growing attention for water treatment purpose. In this study, a series of organic phosphonate salts (OPSs) are synthesized by one-step Mannich-like reaction, confirmed by FTIR and NMR characterizations, and applied as novel draw solutes in FO applications. Their solution properties including osmotic pressures and viscosities, as well as their FO performance as a function of the solution concentration are investigated systematically. In FO process, a higher water flux of 47-54 LMH and a negligible reverse solute flux can be achieved in the PRO (AL-DS) mode (active layer faces the draw solution) using a homemade thin-film composite membrane (PSF-TFC) and deionized water as the feed solution. Among all OPS draw solutes, the tetraethylenepentamine heptakis(methylphosphonic) sodium salt (TPHMP-Na) exhibits the best FO flux at 0.5 mol/kg concentration, which is further applied for the separation of emulsified oil-water mixture. The recovery of diluted OPS solutions is carried out via a nanofiltration (NF) system with a rejection above 92%. The aforementioned features show the great potential of OPS compounds as a novel class of draw solutes for FO applications.

  19. Behaviour of kaolinite intercalation compounds with selected ammonium salts in aqueous chromate and arsenate solutions

    NASA Astrophysics Data System (ADS)

    Matusik, Jakub; Matykowska, Lucyna

    2014-08-01

    The removal of aqueous Cr(VI) and As(V) oxyanions from waters by different materials with sorption properties is of environmental importance. In this study, a methoxy-kaolinite derivative was intercalated with benzyltrimethylammonium (B1), tetramethylammonium (TMA), and benzyldimethylhexadecylammonium (B5) chlorides and the interaction of the obtained materials with oxyanions was examined. The PXRD (powder X-ray diffraction) and IR (Infrared spectroscopy) analyses indicated a monolayer arrangement of the B1 and TMA molecules in the interlayer space of the mineral, while a tilted arrangement was noticed in the case of B5. A complete or partial deintercalation of introduced molecules was observed in the reactions with aqueous solutions of Cr(VI) and As(V). In all studied systems a significant improvement of the oxyanions removal was observed as compared to the pure kaolinite. The highest uptake of oxyanions was noticed in the reaction with B5-intercalated material. This was due to precipitation of organic alkyl salts. The formation of alkylchromate was confirmed using FTIR spectroscopy. The lower uptake of oxyanions by the B1- and TMA-intercalated materials was due to lack of new solid precipitation and resulted from the ion-exchange of chlorides initially compensating the ammonia nitrogen charge. The experimental sorption isotherms for all the reactions were best represented by Langmuir equation. A gradual, two-step removal process of Cr(VI) and As(V) by B1- and TMA-intercalated materials was observed. In turn, the precipitation of alkyl salts in reaction with B5-intercalated material resulted in a rapid immobilization of the oxyanions. The kinetic data modelled using pseudo-second order equation showed very good agreement with experimental results.

  20. Estimation of salt water upconing using a steady-state solution for partial completion of a pumped well.

    PubMed

    Garabedian, Stephen P

    2013-01-01

    A new steady-state analytical solution to the two-dimensional radial-flow equation was developed for drawdown (head) conditions in an aquifer with constant transmissivity, no-flow conditions at the top and bottom, constant head conditions at a known radial distance, and a partially completed pumping well. The solution was evaluated for accuracy by comparison to numerical simulations using MODFLOW. The solution was then used to estimate the rise of the salt water-fresh water interface (upconing) that occurs under a pumping well, and to calculate the critical pumping rate at which the interface becomes unstable, allowing salt water to enter the pumping well. The analysis of salt water-fresh water interface rise assumed no significant effect on upconing by recharge; this assumption was tested and supported using results from a new steady-state analytical solution developed for recharge under two-dimensional radial-flow conditions. The upconing analysis results were evaluated for accuracy by comparison to those from numerical simulations using SEAWAT for salt water-fresh water interface positions under mild pumping conditions. The results from the equation were also compared with those of a published numerical sharp-interface model applied to a case on Cape Cod, Massachusetts. This comparison indicates that estimating the interface rise and maximum allowable pumping rate using the analytical method will likely be less conservative than the maximum allowable pumping rate and maximum stable interface rise from a numerical sharp-interface model.

  1. On the feasibility of near infrared spectroscopy to detect contaminants in water using single salt solutions as model systems.

    PubMed

    Gowen, A A; Marini, F; Tsuchisaka, Y; De Luca, S; Bevilacqua, M; O'Donnell, C; Downey, G; Tsenkova, R

    2015-01-01

    This research work evaluates the feasibility of NIRS to detect contaminants in water using single salt solutions as model systems. Previous research has indicated the potential of near infrared spectroscopy (NIRS) for detecting solutes in water; however, a comprehensive investigation of the limit of detection of this technique has not been carried out. Near infrared transmittance spectra of aqueous salt solutions in the concentration range 0.002-0.1 mol L(-1) (equivalent to 117-13,334 ppm or 0.0001-0.01% mass/mass) were investigated. The first overtone region of the near infrared spectrum (1300-1600 nm) was found to be the most effective wavelength range for prediction of salt concentration in aqueous solutions. Calibration models built using this wavelength range and employing the extended multiplicative scatter spectral pre-treatment resulted in root mean squared error of prediction values ranging from 0.004 to 0.01 mol L(-1). The limit of detection (LOD) was estimated to be of the order of 0.1% (mass/mass) or 1000 ppm. Within the framework of Aquaphotomics, it was possible to examine the effect of different salts on the NIR spectra of water in the first overtone range. Our results were confirmed through test experiments at various geographical locations employing dispersive and Fourier transform type NIRS instruments. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Saturated salt solution method: a useful cadaver embalming for surgical skills training.

    PubMed

    Hayashi, Shogo; Homma, Hiroshi; Naito, Munekazu; Oda, Jun; Nishiyama, Takahisa; Kawamoto, Atsuo; Kawata, Shinichi; Sato, Norio; Fukuhara, Tomomi; Taguchi, Hirokazu; Mashiko, Kazuki; Azuhata, Takeo; Ito, Masayuki; Kawai, Kentaro; Suzuki, Tomoya; Nishizawa, Yuji; Araki, Jun; Matsuno, Naoto; Shirai, Takayuki; Qu, Ning; Hatayama, Naoyuki; Hirai, Shuichi; Fukui, Hidekimi; Ohseto, Kiyoshige; Yukioka, Tetsuo; Itoh, Masahiro

    2014-12-01

    This article evaluates the suitability of cadavers embalmed by the saturated salt solution (SSS) method for surgical skills training (SST). SST courses using cadavers have been performed to advance a surgeon's techniques without any risk to patients. One important factor for improving SST is the suitability of specimens, which depends on the embalming method. In addition, the infectious risk and cost involved in using cadavers are problems that need to be solved. Six cadavers were embalmed by 3 methods: formalin solution, Thiel solution (TS), and SSS methods. Bacterial and fungal culture tests and measurement of ranges of motion were conducted for each cadaver. Fourteen surgeons evaluated the 3 embalming methods and 9 SST instructors (7 trauma surgeons and 2 orthopedists) operated the cadavers by 21 procedures. In addition, ultrasonography, central venous catheterization, and incision with cauterization followed by autosuture stapling were performed in some cadavers. The SSS method had a sufficient antibiotic effect and produced cadavers with flexible joints and a high tissue quality suitable for SST. The surgeons evaluated the cadavers embalmed by the SSS method to be highly equal to those embalmed by the TS method. Ultrasound images were clear in the cadavers embalmed by both the methods. Central venous catheterization could be performed in a cadaver embalmed by the SSS method and then be affirmed by x-ray. Lungs and intestines could be incised with cauterization and autosuture stapling in the cadavers embalmed by TS and SSS methods. Cadavers embalmed by the SSS method are sufficiently useful for SST. This method is simple, carries a low infectious risk, and is relatively of low cost, enabling a wider use of cadavers for SST.

  3. Saturated Salt Solution Method: A Useful Cadaver Embalming for Surgical Skills Training

    PubMed Central

    Hayashi, Shogo; Homma, Hiroshi; Naito, Munekazu; Oda, Jun; Nishiyama, Takahisa; Kawamoto, Atsuo; Kawata, Shinichi; Sato, Norio; Fukuhara, Tomomi; Taguchi, Hirokazu; Mashiko, Kazuki; Azuhata, Takeo; Ito, Masayuki; Kawai, Kentaro; Suzuki, Tomoya; Nishizawa, Yuji; Araki, Jun; Matsuno, Naoto; Shirai, Takayuki; Qu, Ning; Hatayama, Naoyuki; Hirai, Shuichi; Fukui, Hidekimi; Ohseto, Kiyoshige; Yukioka, Tetsuo; Itoh, Masahiro

    2014-01-01

    Abstract This article evaluates the suitability of cadavers embalmed by the saturated salt solution (SSS) method for surgical skills training (SST). SST courses using cadavers have been performed to advance a surgeon's techniques without any risk to patients. One important factor for improving SST is the suitability of specimens, which depends on the embalming method. In addition, the infectious risk and cost involved in using cadavers are problems that need to be solved. Six cadavers were embalmed by 3 methods: formalin solution, Thiel solution (TS), and SSS methods. Bacterial and fungal culture tests and measurement of ranges of motion were conducted for each cadaver. Fourteen surgeons evaluated the 3 embalming methods and 9 SST instructors (7 trauma surgeons and 2 orthopedists) operated the cadavers by 21 procedures. In addition, ultrasonography, central venous catheterization, and incision with cauterization followed by autosuture stapling were performed in some cadavers. The SSS method had a sufficient antibiotic effect and produced cadavers with flexible joints and a high tissue quality suitable for SST. The surgeons evaluated the cadavers embalmed by the SSS method to be highly equal to those embalmed by the TS method. Ultrasound images were clear in the cadavers embalmed by both the methods. Central venous catheterization could be performed in a cadaver embalmed by the SSS method and then be affirmed by x-ray. Lungs and intestines could be incised with cauterization and autosuture stapling in the cadavers embalmed by TS and SSS methods. Cadavers embalmed by the SSS method are sufficiently useful for SST. This method is simple, carries a low infectious risk, and is relatively of low cost, enabling a wider use of cadavers for SST. PMID:25501070

  4. Molecular insights into shellac film coats from different aqueous shellac salt solutions and effect on disintegration of enteric-coated soft gelatin capsules.

    PubMed

    Al-Gousous, J; Penning, M; Langguth, P

    2015-04-30

    The purpose of this investigation was to study the effect of using different salts of shellac on the disintegration properties of shellac-based enteric coatings. In the last two decades, shellac has been increasingly used as an aqueous solution for enteric coating purposes, with the ammonium salt being the form typically used. Little investigation has been performed on using other salts, and therefore, this was the focus of our work. Enteric coatings, based on different shellac salts (ammonium, sodium, potassium and composite ammonium-sodium), were applied onto soft gelatin capsules. Disintegration testing of the coated soft gelatin capsules showed that alkali metal salts promote faster disintegration than ammonium salts. In order to determine the causes behind these differences, the solubility, thermal and spectroscopic properties of films cast from the different salts were investigated. The results show that films cast from ammonium-based salts of shellac are, unlike those cast from alkali metal-based salts, water-insoluble. Spectroscopic evidence suggests that this might be due to partial salt dissociation resulting in loss of ammonium as ammonia and reduced degree of shellac ionization during drying. In addition, oxidation of shellac aldehyde groups of the ammonium-based shellac salts could also play a role. And possible higher extent of shellac hydrolysis during the preparation of alkali metal salts might also be a factor. Therefore, the nature of the shellac salt used in the preparation of shellac-based aqueous coating solutions is a significant formulation factor affecting product performance.

  5. The subtle balance of weak supramolecular interactions: The hierarchy of halogen and hydrogen bonds in haloanilinium and halopyridinium salts.

    PubMed

    Raatikainen, Kari; Cametti, Massimo; Rissanen, Kari

    2010-01-15

    THE SERIES OF HALOANILINIUM AND HALOPYRIDINIUM SALTS: 4-IPhNH₃Cl (1), 4-IPhNH₃Br (5), 4-IPhNH₃H₂PO₄ (6), 4-ClPhNH₃H₂PO₄ (8), 3-IPyBnCl (9), 3-IPyHCl (10) and 3-IPyH-5NIPA (3-iodopyridinium 5-nitroisophthalate, 13), where hydrogen or/and halogen bonding represents the most relevant non-covalent interactions, has been prepared and characterized by single crystal X-ray diffraction. This series was further complemented by extracting some relevant crystal structures: 4-BrPhNH₃Cl (2, CCDC ref. code TAWRAL), 4-ClPhNH₃Cl (3, CURGOL), 4-FPhNH₃Cl (4, ANLCLA), 4-BrPhNH₃H₂PO₄, (7, UGISEI), 3-BrPyHCl, (11, CIHBAX) and 3-ClPyHCl, (12, VOQMUJ) from Cambridge Structural Database for sake of comparison. Based on the X-ray data it was possible to highlight the balance between non-covalent forces acting in these systems, where the relative strength of the halogen bonding C-X...A⁻ (X = I, Br or Cl) and the ratio between the halogen and hydrogen bonds [C-X...A⁻ : D-H...A⁻] varied across the series.

  6. Salt-enhanced removal of 2-ethyl-1-hexanol from aqueous solutions by adsorption on activated carbon.

    PubMed

    Chang, Ganggang; Bao, Zongbi; Zhang, Zhiguo; Xing, Huabin; Su, Baogen; Yang, Yiwen; Ren, Qilong

    2013-12-15

    2-Ethyl-1-hexanol has extensive industrial applications in solvent extraction, however, in view of its potential pollution to environment, the removal and recovery of 2-ethyl-1-hexanol is considered an essential step toward its sustainable use in the future. In this work, we report the removal of 2-ethyl-1-hexanol from aqueous solutions containing salts in high concentrations by adsorption on a coal-based activated carbon. Adsorption thermodynamics showed that the experimental isotherms were conformed well to the Langmuir equation. Also it was found that inorganic salts, i.e. MgCl2 and CaCl2 in high concentration significantly enhanced the adsorption capacity from 223 mg/g in the deionized water to 277 mg/g in a saline water. This phenomenon of adsorption enhancement could be ascribed to the salt-out effect. Kinetic analysis indicated that adsorption kinetics follows the pseudo-second-order equation and the adsorption rate constants increase with the salt concentration. The dynamic breakthrough volume and adsorbed amount of 2-ethyl-1-hexanol were significantly elevated when the salt is present in the water. The dynamic saturated adsorption amount increased from 218.3mg/g in the deionized water to 309.5mg/g in a salt lake brine. The Tomas model was well applied to predict the breakthrough curves and determine the characteristics parameters of the adsorption column. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. The on-line removal of non-regenerable salts from amine solutions using the UCARSEP{reg_sign} Process

    SciTech Connect

    Burns, D.; Gregory, R.A.

    1995-11-01

    Amine unit contamination with non-regenerable salts, whether as a result of acid or inorganic salt incursion, or solvent degradation, is a common industry problem. In MEA systems this is usually addressed by the use of a reclaimer but this is not a practical solution for DEA, MDEA or formulated solvents. Similarly, the old approach of purging solvent is no longer economically or environmentally justifiable. Neutralization of amine salts with a strong base can significantly prolong the useful life of the amine solution but eventually some of the salt may have to be removed, especially if mechanical losses are low. Electrodialysis (ED) has recently been applied to this problem and has been found to overcome many of the disadvantages of vacuum distillation and ion exchange technologies, both of which have been used in recent years for solvent clean-up. Union Carbide adapted ED technology to the unique conditions encountered in an amine system and developed the UCARSEP{reg_sign} Process. A mobile UCARSEP{reg_sign} unit has been built to achieve on-line salt removal rates of 40 lbmol/day (about 3,300 lb/day). This has been successfully used to clean up UCARSOL{reg_sign} solvents as well as DEA. Case studies are presented and the relative merits of this and other clean-up options are discussed.

  8. [Physical and chemical evaluation during refrigeration storage of salted catfish (Pseudoplatystoma sp.) in brine solution, and packed under vacuum].

    PubMed

    Rodríguez, Diana; Barrero, Marinela; Kodaira, Makie

    2009-06-01

    Salting fish in the south Venezuelan towns are still the main method of preserving fish including cutt, and salting fish process, storage and commercialization. As the result, salted-dried fish is particularly susceptible to spoilage by a number of factors, including lipid oxidation, browning meat. Packing salted fish product is an alternative increasing storage life time reducing lost of quality and enhancing the storage time. The present study evaluated the physic, chemist, and sensory quality of fish fillet from cat fish (Pseudoplatystoma sp.) from Apure state, Venezuela. Fillet fish were placed in brine solution at 36% of sodium chloride 1:2 fillet: brine solution; after, they were packed under followed conditions: vacuum, vacuum and storage under refrigeration condition, and room temperature. The results showed significant differences (p < 0.01) for moisture, salt content, and Aw. The fillets packed at vacuum and storage at 4 degrees C were significant different from the resting treatments; not significant differences were presented at room and refrigeration temperature after three moths. The best conditions treatment was vacuum packing and refrigeration at 4 degrees C.

  9. SAVANNAH RIVER SITE INCIPIENT SLUDGE MIXING IN RADIOACTIVE LIQUID WASTE STORAGE TANKS DURING SALT SOLUTION BLENDING

    SciTech Connect

    Leishear, R.; Poirier, M.; Lee, S.; Steeper, T.; Fowley, M.; Parkinson, K.

    2011-01-12

    This paper is the second in a series of four publications to document ongoing pilot scale testing and computational fluid dynamics (CFD) modeling of mixing processes in 85 foot diameter, 1.3 million gallon, radioactive liquid waste, storage tanks at Savannah River Site (SRS). Homogeneous blending of salt solutions is required in waste tanks. Settled solids (i.e., sludge) are required to remain undisturbed on the bottom of waste tanks during blending. Suspension of sludge during blending may potentially release radiolytically generated hydrogen trapped in the sludge, which is a safety concern. The first paper (Leishear, et. al. [1]) presented pilot scale blending experiments of miscible fluids to provide initial design requirements for a full scale blending pump. Scaling techniques for an 8 foot diameter pilot scale tank were also justified in that work. This second paper describes the overall reasons to perform tests, and documents pilot scale experiments performed to investigate disturbance of sludge, using non-radioactive sludge simulants. A third paper will document pilot scale CFD modeling for comparison to experimental pilot scale test results for both blending tests and sludge disturbance tests. That paper will also describe full scale CFD results. The final paper will document additional blending test results for stratified layers in salt solutions, scale up techniques, final full scale pump design recommendations, and operational recommendations. Specifically, this paper documents a series of pilot scale tests, where sludge simulant disturbance due to a blending pump or transfer pump are investigated. A principle design requirement for a blending pump is UoD, where Uo is the pump discharge nozzle velocity, and D is the nozzle diameter. Pilot scale test results showed that sludge was undisturbed below UoD = 0.47 ft{sup 2}/s, and that below UoD = 0.58 ft{sup 2}/s minimal sludge disturbance was observed. If sludge is minimally disturbed, hydrogen will not be

  10. The solution behavior of poly(vinylpyrrolidone): its clouding in salt solution, solvation by water and isopropanol, and interaction with sodium dodecyl sulfate.

    PubMed

    Dan, Abhijit; Ghosh, Soumen; Moulik, Satya P

    2008-03-27

    This article deals with the solution properties of poly(vinylpyrrolidone) (PVP) in salt and surfactant environment. The cloud point (CP) of PVP has been found to be induced by the salts NaCl, KCl, KBr, Na2SO4, MgSO4, and Na3PO4. On the basis of CP values for a salt at different [PVP], the energetics of the clouding process have been estimated. The effect of the surfactant, sodium dodecyl sulfate (SDS), on the salt-induced CP has also been studied, and reduction in CP at low [SDS] and increase in CP at high [SDS] have been observed. The water vapor adsorption of PVP has been determined by isopiestic method. The results display a BET Type III isotherm whose analysis has helped to obtain the monolayer capacity of PVP and formation of multilayer on it. The solvation of PVP in a solution of water and a water-isopropanol mixture has been determined by conductometry from which contribution of the individual components were estimated. The interaction of PVP with SDS in solution led to formation of a complex entity, which has been studied also by conductometry adopting a binding-equilibrium scheme. SDS has been found to undergo two types of binding as monomers in the pre- critical aggregation concentration (CAC) range and as small clusters in the post CAC region. The stoichiometries of binding and binding constant were evaluated.

  11. On heat balance integral solutions of carbonaceous ablator response during reentry

    NASA Astrophysics Data System (ADS)

    Potts, R. L.

    1984-01-01

    Use of the heat balance integral (HBI) method for computing carbonaceous ablator response to reentry is investigated. Realistic models of graphite, carbon-carbon, and carbon-phenolic behavior are presented, including convenient new curve-fit equations. Subtle difficulties in applying HBI to these models are analyzed. HBI calculations show very favorable comparison to finite-difference results (except for in-depth charring of carbon-phenolic) at great savings in cost and are more accurate than quasi-steady solutions of surface response.

  12. Diclofenac Salts, VIII. Effect of the Counterions on the Permeation through Porcine Membrane from Aqueous Saturated Solutions

    PubMed Central

    Fini, Adamo; Bassini, Glenda; Monastero, Annamaria; Cavallari, Cristina

    2012-01-01

    The following bases: monoethylamine (EtA), diethylamine (DEtA), triethylamine (TEtA), monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), pyrrolidine (Py), piperidine (Pp), morpholine (M), piperazine (Pz) and their N-2-hydroxyethyl (HE) analogs were employed to prepare 14 diclofenac salts. The salts were re-crystallized from water in order to obtain forms that are stable in the presence of water. Vertical Franz-type cells with a diffusional surface area of 9.62 cm2 were used to study the permeation of these diclofenac salts from their saturated solutions through an internal pig ear membrane. The receptor compartments of the cells contained 100 mL of phosphate buffer (pH 7.4); a saturated solution (5 mL) of each salt was placed in the donor compartment, thermostated at 37 °C. Aliquots were withdrawn at predetermined time intervals over 8 h and then immediately analyzed by HPLC. Fluxes were determined by plotting the permeated amount, normalized for the membrane surface area versus time. Permeation coefficients were obtained dividing the flux values J by the concentration of the releasing phase—that is, water solubility of each salt. Experimental results show that fluxes could be measured when diclofenac salts with aliphatic amines are released from a saturated aqueous solution. Different chemical species (acid, anion, ion pairs) contribute to permeation of the anti-inflammatory agent even though ion-pairs could be hypothesized to operate to a greater extent. Permeation coefficients were found higher when the counterion contains a ring; while hydroxy groups alone do not appear to play an important role, the ring could sustain permeation, disrupting the organized domains of the membrane. PMID:24300300

  13. A mass-balance model to separate and quantify colloidal and solute redistributions in soil

    USGS Publications Warehouse

    Bern, C.R.; Chadwick, O.A.; Hartshorn, A.S.; Khomo, L.M.; Chorover, J.

    2011-01-01

    Studies of weathering and pedogenesis have long used calculations based upon low solubility index elements to determine mass gains and losses in open systems. One of the questions currently unanswered in these settings is the degree to which mass is transferred in solution (solutes) versus suspension (colloids). Here we show that differential mobility of the low solubility, high field strength (HFS) elements Ti and Zr can trace colloidal redistribution, and we present a model for distinguishing between mass transfer in suspension and solution. The model is tested on a well-differentiated granitic catena located in Kruger National Park, South Africa. Ti and Zr ratios from parent material, soil and colloidal material are substituted into a mixing equation to quantify colloidal movement. The results show zones of both colloid removal and augmentation along the catena. Colloidal losses of 110kgm-2 (-5% relative to parent material) are calculated for one eluviated soil profile. A downslope illuviated profile has gained 169kgm-2 (10%) colloidal material. Elemental losses by mobilization in true solution are ubiquitous across the catena, even in zones of colloidal accumulation, and range from 1418kgm-2 (-46%) for an eluviated profile to 195kgm-2 (-23%) at the bottom of the catena. Quantification of simultaneous mass transfers in solution and suspension provide greater specificity on processes within soils and across hillslopes. Additionally, because colloids include both HFS and other elements, the ability to quantify their redistribution has implications for standard calculations of soil mass balances using such index elements. ?? 2011.

  14. Anomalous ion effects on rupture and lifetime of aqueous foam films from monovalent salt solutions up to saturation concentration

    NASA Astrophysics Data System (ADS)

    Karakashev, S. I.; Nguyen, P. T.; Tsekov, R.; Hampton, M. A.; Nguyen, A. V.

    2008-09-01

    We report the effects of ions on rupture and lifetime of aqueous foam films formed from sodium chloride (NaCl), lithium chloride (LiCl), sodium acetate (NaAc), and sodium chlorate (NaClO 3) using microinterferometry. In the case of NaCl and LiCl, the foam films prepared from the salt solutions below 0.1 M were unstable they thinned until rupturing. The film lifetime measured from the first interferogram (appearing at a film thickness on the order of 500 nm) until the film rupture was only a second or so. However, relatively long lasting and nondraining films prepared from salt solutions above 0.1 M were observed. The film lifetime was significantly longer by 1 to 2 orders of magnitude, i.e., from 10 to 100 s. Importantly, both the film lifetime and the (average) thickness of the nondraining films increased with increasing salt concentration. This effect has not been observed with foam films stabilized by surfactants. The film lifetime and thickness also increased with increasing film radius. The films exhibited significant surface corrugations. The films with large radii often contained standing dimples. There was a critical film radius below which the films thinned until rupturing. In the cases of NaAc and NaClO 3, the films were unstable at all radii and salt concentrations they thinned until rupturing, ruling out the effect of solution viscosity on stabilizing the films.

  15. Survival of Bifidobacterium longum immobilized in calcium alginate beads in simulated gastric juices and bile salt solution.

    PubMed

    Lee, K Y; Heo, T R

    2000-02-01

    Bifidobacterium longum KCTC 3128 and HLC 3742 were independently immobilized (entrapped) in calcium alginate beads containing 2, 3, and 4% sodium alginate. When the bifidobacteria entrapped in calcium alginate beads were exposed to simulated gastric juices and a bile salt solution, the death rate of the cells in the beads decreased proportionally with an increase in both the alginate gel concentration and bead size. The initial cell numbers in the beads affected the numbers of survivors after exposure to these solutions; however, the death rates of the viable cells were not affected. Accordingly, a mathematical model was formulated which expressed the influences of several parameters (gel concentration, bead size, and initial cell numbers) on the survival of entrapped bifidobacteria after sequential exposure to simulated gastric juices followed by a bile salt solution. The model proposed in this paper may be useful for estimating the survival of bifidobacteria in beads and establishing optimal entrapment conditions.

  16. Measurement of Silver-π Interactions in Solution Using Molecular Torsion Balances.

    PubMed

    Maier, Josef M; Li, Ping; Hwang, Jungwun; Smith, Mark D; Shimizu, Ken D

    2015-07-01

    A new series of molecular torsion balances were designed to measure the strength of individual Ag-π interactions in solution for an Ag(I) coordinated to a pyridine nitrogen. The formation of a well-defined intramolecular Ag-π interaction in these model systems was verified by X-ray crystallography and (1)H NMR. The strength of the intramolecular Ag-π interaction in solution was found to be stabilizing in nature and quantified to be -1.34 to -2.63 kcal/mol using a double mutant cycle analysis. The Ag-π interaction was also found to be very sensitive to changes in geometry or solvent environment.

  17. Effects on coagulation of balanced (130/0.42) and non-balanced (130/0.4) hydroxyethyl starch or gelatin compared with balanced Ringer's solution: an in vitro study using two different viscoelastic coagulation tests ROTEMTM and SONOCLOTTM.

    PubMed

    Casutt, M; Kristoffy, A; Schuepfer, G; Spahn, D R; Konrad, C

    2010-09-01

    Hydroxyethyl starch (HES) solutions compromise blood coagulation. Low molecular weight, low-substituted HES products, and electrolyte-balanced solutions might reduce this effect. We compared the effects of in vitro haemodilution on blood coagulation with a balanced 6% HES 130/0.42 solution (HES(BAL)), a saline-based 6% HES 130/0.4 solution (HES(SAL)), a balanced lactated Ringer's solution (RL) and a saline-based 4% gelatin solution (GEL). Blood was obtained from 10 healthy male volunteers and diluted with the test solutions by 33% and 66%. Quality of clot formation was measured using two viscoelastic coagulation tests: SONOCLOT and activated rotation thromboelastometry ROTEM. Of 16 parameters measured by the viscoelastic devices, we found three statistically significant differences compared with baseline for RL, but 11 for GEL, 10 for HES(SAL), and 11 for HES(BAL) in the 33% haemodilution group (P=0.01). Comparing the different solutions, we observed a significant difference between crystalloids and colloids but none between GEL and HES. In the 66% dilution group, effects on blood coagulation were increased when compared with the 33% dilution group. We found no differences in coagulation impairment between balanced and non-balanced HES products and no differences in the detection of impaired blood coagulation due to haemodilution between the two viscoelastic coagulation tests. Both ROTEM and SONOCLOT are sensitive tests for the detection of impaired blood coagulation due to haemodilution. There are fewer effects on blood coagulation using crystalloids compared with colloids. The effects of GEL and HES are similar. There is no difference between balanced HES 130/0.42 and non-balanced HES 130/0.4.

  18. Protein-salt binding data from potentiometric titrations of lysozyme in aqueous solutions containing KCl

    SciTech Connect

    Engmann, J.; Blanch, H.W.; Prausnitz, J.M. |

    1997-03-01

    An existing method for potentiometric titrations of proteins was improved, tested and applied to titrations of the enzyme hen-egg-white lysozyme in aqueous solutions containing KCl at ionic strengths from 0.1 M to 2.0 M at 25 C. Information about the protein`s net charge dependence on pH and ionic strength were obtained and salt binding numbers for the system were calculated using a linkage concept. For the pH range 2.5--11.5, the net charge slightly but distinctly increases with increasing ionic strength between 0.1 M and 2.0 M. The differences are most distinct in the pH region below 5. Above pH 11.35, the net charge decreases with increasing ionic strength. Preliminary calculation of binding numbers from titration curves at 0.1 M and 1.0 M showed selective association of chloride anions and expulsion of potassium ions at low pH. Ion-binding numbers from this work will be used to evaluate thermodynamic properties and to correlate crystallization or precipitation phase-equilibrium data in terms of a model based on the integral-equation theory of fluids which is currently under development.

  19. Salting-Out of Methane in the Aqueous Solutions of Urea and Glycine-Betaine.

    PubMed

    Dixit, Mayank Kumar; Siddique, Asrar A; Tembe, B L

    2015-08-27

    We have studied the hydrophobic association and solvation of methane molecules in aqueous solutions of urea and glycine betaine (GB). We have calculated the potentials of mean force (PMFs) between methane molecules in water, aqueous GB, aqueous urea and aqueous urea-GB mixtures. The PMFs and equilibrium constants indicate that both urea and GB increase the hydrophobic association of methane. Calculation of thermodynamic parameters shows that the association of methane is stabilized by entropy whereas solvation is favored by enthalpy. In the case of the water-urea-GB mixture, both hydrophobic association and solvation are stabilized by entropy. From the investigation of radial distribution functions, running coordination numbers and excess coordination numbers, we infer that both urea and GB are preferentially excluded from methane surface in the mixtures of osmolytes and methane is preferentially solvated by water molecules in all the mixtures. The favorable exclusion of both urea and GB from the methane surface suggests that both urea and GB increase the interaction between methane molecules, i.e., salting-out of methane. We observe that addition of both urea and GB to water enhances local water structure. The calculated values of diffusion constants of water also suggest enhanced water-water interactions in the presence of urea and GB. The calculated free energies of methane in these mixtures show that methane is less soluble in the mixtures of urea and GB than in water. The data on solvation free energies support the observations obtained from the PMFs of methane molecules.

  20. Cyclodextrin-benzoic acid binding in salt solutions: effects of biologically relevant anions.

    PubMed

    Terekhova, I V; Chibunova, E S; Kumeev, R S; Alper, G A

    2014-09-22

    Inclusion complex formation of benzoic acid with α-, β- and γ-cyclodextrins in water and in 0.2 M solutions of inorganic salts (KCl, KBr, KH2PO4 and K2SO4) has been studied by means of 1H NMR at 298.15 K. Binding constants have been determined and role of biologically active inorganic anions in the inclusion complex formation has been revealed. It has been shown that effects of the anions are determined not only by changing the ionic strength. More pronounced influence of Br- and H2PO4- compared with Cl- and SO4(2-) is caused by specific ion-molecular interactions, occurrence of which depends on the physical-chemical properties of the anions as well as on the binding mode of cyclodextrins with benzoic acid. Competing interactions of cyclodextrin-anion were observed in the presence of KBr, while the ternary complex formation was detected upon addition of KH2PO4. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Synergistic effects of inorganic salt and surfactant on phenanthrene removal from aqueous solution by sediment.

    PubMed

    Zhang, Xiaoyan; Wu, Yaoguo; Hu, Sihai; Lu, Cong

    2014-01-01

    The economic and effective application of surfactant enhanced remediation (SER) technology in a sediment-freshwater/saline water system was investigated by batch method using the combined effects of inorganic salt (sodium chloride, NaCl) and anionic surfactant (sodium dodecylbenzene sulfonate (SDBS)) on phenanthrene (PHE) removal via sorption by sediment. In all cases, PHE sorption followed a linear equation and partition as the main mechanism for PHE removal from aqueous solution. Separate addition of SDBS (2 mmol L(-1)) and NaCl (2-100 mmol L(-1)) moderately enhanced PHE removal, while with their combined addition the enhancement was substantial, and the removal efficiency achieved a peak of 92.8%. The combined effect expressed a synergy, and the sorption enhancement increased by factors of 2.7, 3.2 and 3.4 when compared with the sum of the separate entities at elevated salinity. This was because the sorbed SDBS, with increasing amount and a high packing conformation at elevated salinity, outcompeted aqueous SDBS for PHE partition. Moreover, a combination of 2 mmol L(-1) SDBS and 2 mmol L(-1) NaCl was optimal for PHE removal. Therefore, SER technology appears more effective for PHE removal in saline water than in freshwater, and preliminary water quality monitoring is essential for economic and efficient SER application.

  2. Modulation of Elasticity and Interactions in Charged Lipid Multibilayers: Monovalent Salt Solutions

    PubMed Central

    2016-01-01

    We have studied the electrostatic screening effect of NaCl solutions on the interactions between anionic lipid bilayers in the fluid lamellar phase using a Poisson–Boltzmann-based mean-field approach with constant charge and constant potential limiting charge regulation boundary conditions. The full DLVO potential, including the electrostatic, hydration and van der Waals interactions, was coupled to thermal bending fluctuations of the membranes via a variational Gaussian Ansatz. This allowed us to analyze the coupling between the osmotic pressure and the fluctuation amplitudes and compare them both simultaneously with their measured dependence on the bilayer separation, determined by the small-angle X-ray scattering experiments. High-structural resolution analysis of the scattering data revealed no significant changes of membrane structure as a function of salt concentration. Parsimonious description of our results is consistent with the constant charge limit of the general charge regulation phenomenology, with fully dissociated lipid charge groups, together with a 6-fold reduction of the membranes’ bending rigidity upon increasing NaCl concentration. PMID:27993014

  3. Quantitative comparison of topical aluminum salt solution efficacy for management of sweating: a randomized, controlled trial.

    PubMed

    Swary, Jillian H; West, Dennis P; Kakar, Rohit; Ortiz, Sara; Schaeffer, Matthew R; Veledar, Emir; Alam, Murad

    2015-12-01

    There is a lack of studies objectively comparing the efficacy of topical antiperspirants in reducing sweat. To objectively and quantitatively compare the efficacy of two aluminum salt solutions for the reduction of induced sweating. A subject, rater, and statistician-blinded, randomized, controlled trial. Nineteen subjects were exposed to a standardized heat challenge for 3 h. Topical agent A (20% aluminum chloride hexahydrate) was randomized to either axilla, and topical agent B (1% aluminum acetate) assigned to the contralateral side. A sauna suit induced sweating during three 30-min heat intervals: (1) with no study agents (pre); (2) with both study agents, one on each side; and (3) after the agents were washed off (post). Sweat levels were measured by securing Whatman(®) filter paper to each axilla and measuring the paper weight after each heat interval. The difference in paper weight following each heat interval between Study Agent A and Study Agent B was measured by a gravimetric scale. Topical agent A had a significantly greater effect at reducing axillary sweating than B (P = 0.0002). In a sweating simulation, 20% aluminum chloride hexahydrate quantitatively and objectively appeared to reduce sweat more effectively than 1% aluminum acetate. © 2015 Wiley Periodicals, Inc.

  4. Influence and hydrolysis kinetics in titanyl sulfate solution from the sodium hydroxide molten salt method

    NASA Astrophysics Data System (ADS)

    Wang, Weijing; Chen, Desheng; Chu, Jinglong; Li, Jie; Xue, Tianyan; Wang, Lina; Wang, Dong; Qi, Tao

    2013-10-01

    Hydrated titanium dioxide (HTD) was precipitated by thermal hydrolysis in purified titanyl sulfate solution (TSS) obtained through the sodium hydroxide molten salt clean method. Various factors including the stirring speed and initial concentrations of TiOSO4, sulfuric acid, and sodium ion were studied. The main influence factors in the hydrolysis process were the initial concentrations of TiOSO4 and sulfuric acid. Contrary to the ferrous ion, the sodium ion improved the ionic activity of Ti4+, but did not decrease the crystal size. The Boltzman growth model (x=A2+(A1-A2)/{1+exp[(t-t0)/dt)]}, which focuses on two main parameters (CTiOSO4 and CH2SO4), fits the hydrolysis process well with R2>0.97. An increase in sulfuric acid concentration negatively affected the hydrolysis rates and the value of A2, while t0 increased. An increase in titanyl sulfate concentration directly reduced the hydrolysis rates and particle size of HTD, contrary to the trend for the value of t0. A simulation software called 1stopt was used to observe the relationship between Z (A1, A2, t0, dt) and a, b (CTiO2 and CH2SO4).

  5. Salt Solutions in Carbon Nanotubes: The Role of Cation- π Interactions

    NASA Astrophysics Data System (ADS)

    Pham, Tuan Anh; Mortuza, Golam; Wood, Brandon; Lau, Edmond; Ogitsu, Tadashi; Buchsbaum, Steven; Siwy, Zuzanna; Fornasiero, Francesco; Schwegler, Eric

    Understanding the structure of aqueous electrolytes at interfaces is essential for predicting and optimizing device performances for a wide variety of emerging energy and environmental technologies. In this work, we investigate the structure of two common salt solutions, NaCl and KCl, at a hydrophobic interface within narrow carbon nanotubes (CNTs). Using a combination of first-principles and classical molecular dynamics simulations, we find that the solvation structure of the cations in the CNTs can deviate substantially from the conventional weakly interacting hydrophobic picture. Instead, interactions between solvated ions and the π-orbitals of the CNTs are found to play a critically important role, with the ion solvation structure ultimately determined by a subtle interplay between cation- π interactions and the intrinsic flexibility of the solvation shell. In the case of K+, these effects result in an unusually strong propensity to partially desolvate and reside closer to the carbon wall than either Na+ and Cl-, in sharp contrast to the known ion ordering at the water-vapor interface. This work was performed under the auspices of the U.S. Department of Energy by LLNL under Contract DE-AC52-07NA27344.

  6. Factors affecting storage of compressed air in solution mined salt cavities

    SciTech Connect

    Allen, R.D.; Doherty, T.J.; Thoms, R.L.

    1982-08-01

    Geologic factors affecting a salt deposit's acceptability for compressed air energy storage include diameter, depth, thickness, mineralogy, strength, presence of gas, faulting, seismic susceptibility, caprock quality, and rate of dissolution by ground water. Assessment of a potential site involves analyzing existing information, seismic surveying, exploratory drilling, examining salt and caprock, geophysical logging, measuring in situ stress, and determining hydrologic impact. Geologic exploration at Huntorf, Federal Republic of Germany, is discussed. Criteria are presented for cavern design parameters, which include octahedral shear strength, excess lateral stress, depth to cavern top, lateral salt thickness, vertical salt thickness, span, and height-todiameter ratio. Cavern, borehole and surface monitoring methods are discussed.

  7. Self-assembly of micelles in organic solutions of lecithin and bile salt: Mesoscale computer simulation

    NASA Astrophysics Data System (ADS)

    Markina, A.; Ivanov, V.; Komarov, P.; Khokhlov, A.; Tung, S.-H.

    2016-11-01

    We propose a coarse-grained model for studying the effects of adding bile salt to lecithin organosols by means of computer simulation. This model allows us to reveal the mechanisms of experimentally observed increasing of viscosity upon increasing the bile salt concentration. We show that increasing the bile salt to lecithin molar ratio induces the growth of elongated micelles of ellipsoidal and cylindrical shape due to incorporation of disklike bile salt molecules. These wormlike micelles can entangle into transient network displaying perceptible viscoelastic properties.

  8. Effects of feeding salt-tolerant forage cultivated in saline-alkaline land on rumen fermentation, feed digestibility and nitrogen balance in lamb.

    PubMed

    Wang, Cong; Dong, Kuan Hu; Liu, Qiang; Yang, Wen Zhu; Zhao, Xiang; Liu, Sheng Qiang; He, Ting Ting; Liu, Zhuang Yu

    2011-05-01

    Mixing salt-tolerant plants with other plants may affect rumen fermentation, which could result in an increase of feed conversion rate. The objective of this study was to evaluate the effects of partially or entirely replacing the corn stover with a mixture of salt-tolerant forage (Dahurian wildrye grass, weeping alkaligrass and erect milkvetch) in the diet of lambs on ruminal fermentation, feed digestibility and nitrogen (N) balance. Ratios of corn stover to the mixture of salt-tolerant forages in the four experimental diets were 100:0, 67:33, 33:67 and 0:100, respectively, for control, low (LF), medium (MF) and high (HF). Ruminal pH was lower (P = 0.048) with LF and MF than with control and HF diets. Total VFA concentration was consistently higher (P = 0.039) for LF and MF than for control and HF with increasing amount of salt-tolerant forage. Ratio of acetate to propionate was linearly (P = 0.019) decreased due to the decrease in acetate production. Digestibilities of OM, NDF and CP in the whole tract linearly (P < 0.002) decreased with increasing amount of salt-tolerant forage. Similarly, retained N and ratio of retained N to digestible N also linearly (P < 0.005) decreased. Feeding salt-tolerant forage cultivated in saline-alkaline land improved rumen fermentation with increased total VFA production, and changed the rumen fermentation pattern to increased butyrate production. However, the decreased feed digestibility in the whole digestive tract of lamb may reduce nutrient availability to animals and thus adversely affect animal productivity. Additionally, feeding salt-tolerant forages may require more protein supplement to meet animal requirements, because of the low protein content and low protein digestibility of the salt-tolerant forages. Copyright © 2011 Society of Chemical Industry.

  9. Different sodium salts cause different solute accumulation in the halophyte Prosopis strombulifera.

    PubMed

    Llanes, A; Bertazza, G; Palacio, G; Luna, V

    2013-01-01

    The success of Prosopis strombulifera in growing under high NaCl concentrations involves a carefully controlled balance among different processes, including compartmentation of Cl(-) and Na(+) in leaf vacuoles, exclusion of Na(+) in roots, osmotic adjustment and low transpiration. In contrast, Na(2) SO(4) causes growth inhibition and toxicity. We propose that protection of the cytoplasm can be achieved through production of high endogenous levels of specific compatible solutes. To test our hypothesis, we examined endogenous levels of compatible solutes in roots and leaves of 29-, 40- and 48-day-old P. strombulifera plants grown in media containing various concentrations of NaCl, Na(2) SO(4) or in mixtures of both, with osmotic potentials of -1.0,-1.9 and -2.6 MPa, as correlated with changes in hydric parameters. At 24 h after the last pulse plants grown in high NaCl concentrations had higher relative water content and relatively higher osmotic potential than plants grown in Na(2) SO(4) (at 49 days). These plants also had increased synthesis of proline, pinitol and mannitol in the cytoplasm, accompanied by normal carbon metabolism. When the sulphate anion is present in the medium, the capacities for ion compartmentalisation and osmotic adjustment are reduced, resulting in water imbalance and symptoms of toxicity due to altered carbon metabolism, e.g. synthesis of sorbitol instead of mannitol, reduced sucrose production and protein content. This inhibition was partially mitigated when both anions were present together in the solution, demonstrating a detrimental effect of the sulphate ion on plant growth.

  10. A class of analytic solutions for the thermally balanced magnetostatic prominence sheet

    NASA Technical Reports Server (NTRS)

    Low, B. C.; Wu, S. T.

    1981-01-01

    A theoretical study is presented for the nonlinear interplay between magnetostatic equilibrium and energy balance in a Kippenhahn-Schlueter type solar prominence sheet. A class of theoretical models is presented, expressed in closed analytic forms, thus facilitating the direct illustration of the nonlinear physical properties. The model couples the equilibrium between magnetic field, plasma pressure, and weight on the one hand, with the balance between a rho-squared T radiative loss, a rho wave heating (where rho equals plasma density, and T equals plasma temperature), and thermal conduction channeled along magnetic field lines on the other. The steady solutions are divided into three classes, and are characterized by the total wave heating in the prominence sheet which is greater than, equal to, or less than the total radiative loss. The compaction of the plasma along the field lines, under its own weight, and the energy transport effects determine which of the three basic behaviors obtains in a particular situation. A discussion is presented of the implications of the steady solutions for the formation of prominences.

  11. Simple theoretical model for ion cooperativity in aqueous solutions of simple inorganic salts and its effect on water surface tension.

    PubMed

    Gao, Yi Qin

    2011-11-03

    Careful analysis of experimental data showed that the salt aqueous solution/air surface tension depends on a rather complicated manner of salt composition and points to the importance of ion cooperativity. In this short article, we include the selective binding of anions over cations at interfaces (as revealed from molecular dynamics simulations, spectroscopic measurements, and Record's analysis of the surface tension data) and the anion-cation association (based on the observation of matching water affinity) in a simple theoretical model to understand salt effects on surface tension. The introduction of the surface effect and ion association provides a qualitative explanation of the experimental data, in particular, the strong anion dependence of the cations' rank according to their ability of increasing water surface tension. We hope that the physical insight provided by this study can be used to point to new directions for more detailed studies.

  12. Global Classical Solutions for Partially Dissipative Hyperbolic System of Balance Laws

    NASA Astrophysics Data System (ADS)

    Xu, Jiang; Kawashima, Shuichi

    2014-02-01

    The basic existence theory of Kato and Majda enables us to obtain local-in-time classical solutions to generally quasilinear hyperbolic systems in the framework of Sobolev spaces (in x) with higher regularity. However, it remains a challenging open problem whether classical solutions still preserve well-posedness in the case of critical regularity. This paper is concerned with partially dissipative hyperbolic system of balance laws. Under the entropy dissipative assumption, we establish the local well-posedness and blow-up criterion of classical solutions in the framework of Besov spaces with critical regularity with the aid of the standard iteration argument and Friedrichs' regularization method. Then we explore the theory of function spaces and develop an elementary fact that indicates the relation between homogeneous and inhomogeneous Chemin-Lerner spaces (mixed space-time Besov spaces). This fact allows us to capture the dissipation rates generated from the partial dissipative source term and further obtain the global well-posedness and stability by assuming at all times the Shizuta-Kawashima algebraic condition. As a direct application, the corresponding well-posedness and stability of classical solutions to the compressible Euler equations with damping are also obtained.

  13. Saturated salt solution: a further step to a formaldehyde-free embalming method for veterinary gross anatomy.

    PubMed

    Lombardero, M; Yllera, M M; Costa-E-Silva, A; Oliveira, M J; Ferreira, P G

    2017-08-01

    In the field of veterinary anatomy, most of the specimens used in practical sessions are perfused with fixatives. Thus, they can be used for a longer time, reducing the number of animals for educational purposes. Formalin is the most commonly used fixative, consisting of a 37% formaldehyde solution. However, formaldehyde is a powerful irritant of the eyes and airways and is considered carcinogenic, causing nasopharyngeal cancer in exposed workers and professionals. In the present study, we explored an alternative method to avoid the use of formaldehyde in specimens used for gross anatomy practical sessions. We propose an inexpensive, non-toxic fixative that is available worldwide, such as sea salt. This method consists of a continuous perfusion of saturated salt solution for a period of 6-8 h, enabling drainage of the solution to avoid a weight increase of the specimen, and allowing salt to be retained in the tissue. The method is based on recirculation of the saturated salt solution instead of maceration. Perfused specimens retained their natural consistency and joint mobility, with no blood, resembling a piece of meat from the slaughterhouse. They could be used immediately without a maceration period, or stored in the fridge until use and then kept in a bath of saturated salt solution for future conservation. In the case of the former, no refrigeration was needed. The specimens did not have an irritating or offensive smell, and could be used for long sessions (several hours per day) and stored for long periods. However, the blood vessels used for perfusion determine the results: a less invasive approach (through common carotid arteries) gave good preservation of the musculoskeletal system, whereas more invasive access to cannulate the abdominal aorta and vena cava caudalis was required to achieve better preservation of the viscera. In conclusion, we propose that perfusion followed by immersion in a saturated salt solution is a good alternative method for the

  14. A mechanistic analysis of the increase in the thermal stability of proteins in aqueous carboxylic acid salt solutions.

    PubMed Central

    Kaushik, J. K.; Bhat, R.

    1999-01-01

    The stability of proteins is known to be affected significantly in the presence of high concentration of salts and is highly pH dependent. Extensive studies have been carried out on the stability of proteins in the presence of simple electrolytes and evaluated in terms of preferential interactions and increase in the surface tension of the medium. We have carried out an in-depth study of the effects of a series of carboxylic acid salts: ethylene diamine tetra acetate, butane tetra carboxylate, propane tricarballylate, citrate, succinate, tartarate, malonate, and gluconate on the thermal stability of five different proteins that vary in their physico-chemical properties: RNase A, cytochrome c, trypsin inhibitor, myoglobin, and lysozyme. Surface tension measurements of aqueous solutions of the salts indicate an increase in the surface tension of the medium that is very strongly correlated with the increase in the thermal stability of proteins. There is also a linear correlation of the increase in thermal stability with the number of carboxylic groups in the salt. Thermal stability has been found to increase by as much as 22 C at 1 M concentration of salt. Such a high thermal stability at identical concentrations has not been reported before. The differences in the heat capacities of denaturation, deltaCp for RNase A, deduced from the transition curves obtained in the presence of varying concentrations of GdmCl and that of carboxylic acid salts as a function of pH, indicate that the nature of the solvent medium and its interactions with the two end states of the protein control the thermodynamics of protein denaturation. Among the physico-chemical properties of proteins, there seems to be an interplay of the hydrophobic and electrostatic interactions that lead to an overall stabilizing effect. Increase in surface free energy of the solvent medium upon addition of the carboxylic acid salts appears to be the dominant factor in governing the thermal stability of proteins

  15. Ion aggregation in high salt solutions. V. Graph entropy analyses of ion aggregate structure and water hydrogen bonding network

    NASA Astrophysics Data System (ADS)

    Choi, Jun-Ho; Cho, Minhaeng

    2016-05-01

    Dissolved ions in water tend to form polydisperse ion aggregates such as ion pairs, relatively compact ion clusters, and even spatially extended ion networks with increasing salt concentration. Combining molecular dynamics simulation and graph theoretical analysis methods, we recently studied morphological structures of ion aggregates with distinctively different characteristics. They can be distinguished from each other by calculating various spectral graph theoretical properties such as eigenvalues and eigenvectors of adjacency matrices of ion aggregates and water hydrogen-bonding networks, minimum path lengths, clustering coefficients, and degree distributions. Here, we focus on percolation and graph entropic properties of ion aggregates and water hydrogen-bonding networks in high salt solutions. Ion network-forming K+ and SCN- ions at high concentrations show a percolating behavior in their aqueous solutions, but ion cluster-forming ions in NaCl solutions do not show such a transition from isolated ion aggregates to percolating ion-water mixture morphology. Despite that the ion aggregate structures are strikingly different for either cluster- or network-forming ions in high salt solutions, it is interesting that the water structures remain insensitive to the electrostatic properties, such as charge densities and polydentate properties, of dissolved ions, and morphological structures of water H-bonding networks appear to be highly robust regardless of the nature and concentration of salt. We anticipate that the present graph entropy analysis results would be of use in understanding a variety of anomalous behaviors of interfacial water around biomolecules as well as electric conductivities of high electrolyte solutions.

  16. Growth of single crystals of organic salts with large second-order optical nonlinearities by solution processes for devices

    NASA Technical Reports Server (NTRS)

    Leslie, Thomas M.

    1995-01-01

    Data obtained from the electric field induced second harmonic generation (EFISH) and Kurtz Powder Methods will be provided to MSFC for further refinement of their method. A theoretical model for predicting the second-order nonlinearities of organic salts is being worked on. Another task is the synthesis of a number of salts with various counterions. Several salts with promising SHG activities and new salts will be tested for the presence of two crystalline forms. The materials will be recrystallized from dry and wet solvents and compared for SHG efficiency. Salts that have a high SHG efficiency and no tendency to form hydrates will be documented. The synthesis of these materials are included in this report. A third task involves method to aid in the growth of large, high quality single crystals by solution processes. These crystals will be characterized for their applicability in the fabrication of devices that will be incorporated into optical computers in future programs. Single crystals of optimum quality may be obtained by crystal growth in low-gravity. The final task is the design of a temperature lowering single crystal growth apparatus for ground based work. At least one prototype will be built.

  17. Osmotic second virial cross-coefficient measurements for binary combination of lysozyme, ovalbumin, and α-amylase in salt solutions.

    PubMed

    Mehta, Chirag M; White, Edward T; Litster, James D

    2013-01-01

    Interactions measurement is a valuable tool to predict equilibrium phase separation of a desired protein in the presence of unwanted macromolecules. In this study, cross-interactions were measured as the osmotic second virial cross-coefficients (B23 ) for the three binary protein systems involving lysozyme, ovalbumin, and α-amylase in salt solutions (sodium chloride and ammonium sulfate). They were correlated with solubility for the binary protein mixtures. The cross-interaction behavior at different salt concentrations was interpreted by either electrostatic or hydrophobic interaction forces. At low salt concentrations, the protein surface charge dominates cross-interaction behavior as a function of pH. With added ovalbumin, the lysozyme solubility decreased linearly at low salt concentration in sodium chloride and increased at high salt concentration in ammonium sulfate. The B23 value was found to be proportional to the slope of the lysozyme solubility against ovalbumin concentration and the correlation was explained by preferential interaction theory. © 2013 American Institute of Chemical Engineers.

  18. Method of utilizing solar ponds for effecting controlled temperature changes of solutions particularly in processes involving the dissolution and/or precipitation of salts

    SciTech Connect

    Shachar, S.

    1982-06-08

    A method of changing the salt content of a solution is described by including the salt in a nonconvective solar pond heated by solar radiation and having stable salt-concentration and temperature gradients increasing from the top to the bottom of the pond, the bottom layer of the pond being a substantially saturated solution at a predetermined temperature. A feed solution containing the salt is introduced directly into the bottom layer and is circulated through the bottom layer. The predetermined temperature of the bottom layer is different from the initial temperature of the feed solution when introduced into the pond bottom layer and is selected to effect a change in solubility, and thereby a change in the salt content, of the feed solution by causing salt in the feed solution to be precipitated therefrom, or additional salt to be dissolved therein. Examples are described in which the solar pond is used for the production of sodium sulphate, dehydration of other salts, upgrading of carnalite, production of potassium chloride, and production of various minerals from the Dead Sea.

  19. Differential Solute Regulation in Leaf Blades of Various Ages in Salt-Sensitive Wheat and a Salt-Tolerant Wheat x Lophopyrum elongatum (Host) A. Love Amphiploid.

    PubMed Central

    Colmer, T. D.; Epstein, E.; Dvorak, J.

    1995-01-01

    Leaf blades of different ages from a salt-tolerant wheat x Lophopyrum elongatum (Host) A. Love (syn. Agropyron elongatum Host) amphiploid and its salt-sensitive wheat parent (Triticum aestivum L.cv Chinese Spring) were compared for their ionic relations, organic solute accumulation, and sap osmotic potential ([pi]sap). The plants were grown for 18 d in nonsaline (1.25 mM Na+) and salinized (200 mM NaCl) nutrient solutions. The response of leaf blades to NaCl salinity depended greatly on their age or position on the main stem. Na and proline levels were highest in the oldest leaf blade and progressively lower in younger ones. Glycine betaine and asparagine levels were highest in the youngest blade. The [pi]sap was similar for corresponding leaf blades of both genotypes, but contributions of various solutes to the difference in [pi]sap between blades from control and 200 mM NaCl treatments differed greatly. The NaCl-induced decline in [pi]sap of the youngest leaf blade of Chinese Spring was predominately due to the accumulation of Na and to a lesser extent asparagine; in the amphiploid, it was due to a combination of glycine betaine, K, Na, and asparagine. Proline contributed little in the youngest blade of either genotype. In the older blades Na was the major solute contributing to the decline in [pi]sap. Thus, the maintenance of low Na and high K levels and the accumulation of glycine betaine in the young leaf tissues contributed to the NaCl tolerance of the amphiploid. No such role was evident for proline. PMID:12228575

  20. A novel method of non-violent dissolution of sodium metal in a concentrated aqueous solution of Epsom salt

    NASA Astrophysics Data System (ADS)

    Lakshmanan, A. R.; Prasad, M. V. R.; Ponraju, D.; Krishnan, H.

    2004-10-01

    A new technique of non-violent and fast dissolution of sodium metal in a concentrated aqueous solution of Epsom salt (MgSO4.7H2O) at room temperature (RT) has been developed. The dissolution process is mildly exothermic but could be carried out even in a glass beaker in air under swift stirring condition. The reaction products consist of mixed salts of MgSO4 and Na2SO4 as well as Mg(OH)2 which are only mildly alkaline and hence are non-corrosive and non-hazardous unlike NaOH. A 50 mL solution having Epsom salt concentration of 2 M was found to give the optimal composition for disposal of 1 g of sodium. Supersaturated (>2.7 M), as well as dilute (<1.1 M) solutions, however, cause violent reactions and hence should be avoided. Repeated sodium dissolution in Epsom solution produced a solid waste of 4.7 g per g of sodium dissolved which is comparable with the waste (4 g) produced in 8 M NaOH solution. A 1.4 M Epsom solution sprayed with a high-pressure jet cleaner at RT in air easily removed the sodium blocked inside a metal pipe made of mild steel. The above jet also dissolved peacefully residual sodium collected on the metal tray after a sodium fire experiment. No sodium fire or explosion was observed during this campaign. The Epsom solution spray effectively neutralized the minor quantity of sodium aerosol produced during this campaign. This novel technique would hence be quite useful for draining sodium from fast breeder reactor components and bulk processing of sodium as well as for sodium fire fighting.

  1. Workman-Reynolds freezing potential measurements between ice and dilute salt solutions for single ice crystal faces.

    PubMed

    Wilson, P W; Haymet, A D J

    2008-09-18

    Workman-Reynolds freezing potentials have been measured for the first time across the interface between single crystals of ice 1h and dilute electrolyte solutions. The measured electric potential is a strictly nonequilibrium phenomenon and a function of the concentration of salt, freezing rate, orientation of the ice crystal, and time. When all these factors are controlled, the voltage is reproducible to the extent expected with ice growth experiments. Zero voltage is obtained with no growth or melting. For rapidly grown ice 1h basal plane in contact with a solution of 10 (-4) M NaCl the maximum voltage exceeds 30 V and decreases to zero at both high and low salt concentrations. These single-crystal experiments explain much of the data captured on this remarkable phenomenon since 1948.

  2. Ion aggregation in high salt solutions. II. Spectral graph analysis of water hydrogen-bonding network and ion aggregate structures.

    PubMed

    Choi, Jun-Ho; Cho, Minhaeng

    2014-10-21

    Graph theory in mathematics and computer science is the study of graphs that are structures with pairwise connections between any objects. Here, the spectral graph theory and molecular dynamics simulation method are used to describe both morphological variation of ion aggregates in high salt solutions and ion effects on water hydrogen-bonding network structure. From the characteristic value analysis of the adjacency matrices that are graph theoretical representations of ion clusters, ion networks, and water H-bond structures, we obtained the ensemble average eigenvalue spectra revealing intricate connectivity and topology of ion aggregate structure that can be classified as either ion cluster or ion network. We further show that there is an isospectral relationship between the eigenvalue spectra of ion networks in high KSCN solutions and those of water H-bonding networks. This reveals the isomorphic relationship between water H-bond structure and ion-ion network structure in KSCN solution. On the other hand, the ion clusters formed in high NaCl solutions are shown to be graph-theoretically and morphologically different from the ion network structures in KSCN solutions. These observations support the bifurcation hypothesis on large ion aggregate growth mechanism via either ion cluster or ion network formation. We thus anticipate that the present spectral graph analyses of ion aggregate structures and their effects on water H-bonding network structures in high salt solutions can provide important information on the specific ion effects on water structures and possibly protein stability resulting from protein-water interactions.

  3. Adsorption of sulfur dioxide on natural clinoptilolite chemically modified with salt solutions.

    PubMed

    Ivanova, Emilia; Koumanova, Bogdana

    2009-08-15

    Various ion exchange forms of preliminary partly decationised zeolite (hydrogen forms) were obtained by indirect modification with metal salt solutions, as well as by direct treatment of natural clinoptilolite taken from Bulgarian deposits. Direct modification leads to a higher extent of samples enrichment with corresponding ion. Independently of the conditions, the alkaline and alkaline earth metal ions (especially sodium and calcium) were inserted at a greater extent, while the transitional metals-at a comparatively lower extent. The cationic forms of clinoptilolite were used for adsorption and desorption experiments. The breakthrough adsorption curves and the concentration curves at temperature-programmed desorption were obtained and compared. The breakthrough and saturation times, the adsorption capacity, the distribution coefficient, the adsorbed SO(2), the portions desorbed as SO(2) and SO(3), respectively, as well as the not desorbed portion of SO(2), were determined using these curves. It was established that a definite quantity of undesorbed SO(2) has remained in the zeolite forms modified with transitional metal cations. This statement was proved not only by the comparison between the adsorbed and desorbed quantities, but also by three-cycle adsorption-desorption experiments for the Cu(2+)-form. The results demonstrate a decrease in the capacity for each following cycle in an extent similar to the undesorbed SO(2) quantity. It was not observed a visible difference in the values of the distribution coefficients for adsorption on identical cation forms, directly or indirectly obtained. However, the breakthrough time of the samples obtained by ion exchange of the hydrogen form was longer in all cases. Definite quantities of desorbed SO(3) were registered for all forms, except for the natural clinoptilolite and the samples enriched with alkaline and alkaline earth metal cations.

  4. Results For The Third Quarter Calendar Year 2016 Tank 50H Salt Solution Sample

    SciTech Connect

    Crawford, C.

    2016-10-13

    In this memorandum, the chemical and radionuclide contaminant results from the Third Quarter Calendar Year 2016 (CY16) sample of Tank 50H salt solution are presented in tabulated form. The Third Quarter CY16 Tank 50H samples (a 200 mL sample obtained 6” below the surface (HTF-5-16-63) and a 1 L sample obtained 66” from the tank bottom (HTF-50-16-64)) were obtained on July 14, 2016 and received at Savannah River National Laboratory (SRNL) on the same day. Prior to obtaining the samples from Tank 50H, a single pump was run at least 4.4 hours, and the samples were pulled immediately after pump shut down. The information from this characterization will be used by Defense Waste Processing Facility (DWPF) & Saltstone Facility Engineering for the transfer of aqueous waste from Tank 50H to the Saltstone Production Facility, where the waste will be treated and disposed of in the Saltstone Disposal Facility. This memorandum compares results, where applicable, to Saltstone Waste Acceptance Criteria (WAC) limits and targets. Data pertaining to the regulatory limits for Resource Conservation and Recovery Act (RCRA) metals will be documented at a later time per the Task Technical and Quality Assurance Plan (TTQAP) for the Tank 50H saltstone task. The chemical and radionuclide contaminant results from the characterization of the Third Quarter CY16 sampling of Tank 50H were requested by Savannah River Remediation (SRR) personnel and details of the testing are presented in the SRNL TTQAP.

  5. Geobacter sp. SD-1 with enhanced electrochemical activity in high-salt concentration solutions.

    PubMed

    Sun, Dan; Call, Douglas; Wang, Aijie; Cheng, Shaoan; Logan, Bruce E

    2014-12-01

    An isolate, designated strain SD-1, was obtained from a biofilm dominated by Geobacter sulfurreducens in a microbial fuel cell. The electrochemical activity of strain SD-1 was compared with type strains, G. sulfurreducens PCA and Geobacter metallireducens GS-15, and a mixed culture in microbial electrolysis cells. SD-1 produced a maximum current density of 290 ± 29 A m−3 in a high-concentration phosphate buffer solution (PBS-H, 200 mM). This current density was significantly higher than that produced by the mixed culture (189 ± 44 A m−3) or the type strains (< 70 A m−3). In a highly saline water (SW; 50 mM PBS and 650 mM NaCl), current by SD-1 (158 ± 4 A m−3) was reduced by 28% compared with 50 mM PBS (220 ± 4 A m−3), but it was still higher than that of the mixed culture (147 ± 19 A m−3), and strains PCA and GS-15 did not produce any current. Electrochemical tests showed that the improved performance of SD-1 was due to its lower charge transfer resistance and more negative potentials produced at higher current densities. These results show that the electrochemical activity of SD-1 was significantly different than other Geobacter strains and mixed cultures in terms of its salt tolerance.

  6. Effects of solution mining of salt on wetland hydrology as inferred from tree rings

    USGS Publications Warehouse

    Yanosky, T.M.; Kappel, W.M.

    1997-01-01

    Radial growth and concentrations of selected elements within rings were studied in white pine (Pinus strobus) trees from a wetland in central New York approximately 5 km north of a salt-solution mining field that operated from 1889 to 1988. Trees seemingly document three sequential episodes of mine-induced alterations of groundwater discharge irrigating the wetland during the 100-year period. The radial growth of trees established before the onset of mining declined abruptly in the early 1890s and remained suppressed until about 1960, as did growth of numerous other trees that became established after the onset of mining. Suppressed pre-1960 radial growth coincided with the interval that surface water was injected into the saltbeds, suggesting that losses of injected water to the bedrock and/or unconsolidated deposits increased groundwater flow into the wetland. An abrupt and sustained enhancement of radial growth beginning about 1960 indicates that the wetland became drier, and thus more conducive to tree growth, when injection practices were discontinued in the late 1950s despite the continued pumping of brine. Following the cessation of mining in the late 1980s, head pressures again increased in the upper valley, driving chloride-enriched flow northward along regional bedding-plane fractures and into the wetland. Large concentrations of chloride were detected within the most recently formed rings of some trees. As the result of chloride-enriched irrigation, the radial growth of some trees declined, and some trees died. Thus trees have preserved evidence of a century of hydrologic alterations, unobtainable by other means, where the effects of brine mining have not been documented previously.

  7. Estimating the saline springs component in the solute and water balance of Lake Kinneret, Israel

    NASA Astrophysics Data System (ADS)

    Rimmer, Alon; Gal, Gideon

    2003-12-01

    The relatively high salinity of Lake Kinneret, Israel (190-350 ppm Cl -) is a result of the activity of saline springs located at the bottom of the lake. Their subsurface location inhibits direct monitoring of their fluxes. The objective of this work is to characterize the monthly ground water flow and salinity of the unmonitored saline springs over a long-term period, and to find a functional relationship between deriving variables and these monthly discharges. Results of the long-term evaluation of the unmonitored saline springs activity, are intended to help distinguish between two competing models ('gravity driven flow' (GFM) and 'self potential' models), which were proposed as the mechanism of the Lake Kinneret saline springs. The monthly solute and water balance of 32 consecutive years (1968-2001) was calculated, in which the contribution of the saline springs was considered as the residual. Error analyses were conducted for both the water and the solute residuals, and constraints were used to calculate a better, physically based time series representing the unmonitored saline springs activity. The calculated time-series of water and solute discharge from the springs were used to find the functional relationship with the lake level. It was found that there was an increase of water and solute fluxes to the lake at periods of high lake level. We concluded that the results are in agreement with the proposed GFM: high fluxes of ground water to the lake, and high leaching of solute are the result of rainy seasons, which usually cause high lake levels as well.

  8. Balancing Osmotic Pressure of Electrolytes for Nanoporous Membrane Vanadium Redox Flow Battery with a Draw Solute.

    PubMed

    Yan, Ligen; Li, Dan; Li, Shuaiqiang; Xu, Zhi; Dong, Junhang; Jing, Wenheng; Xing, Weihong

    2016-12-28

    Vanadium redox flow batteries with nanoporous membranes (VRFBNM) have been demonstrated to be good energy storage devices. Yet the capacity decay due to permeation of vanadium and water makes their commercialization very difficult. Inspired by the forward osmosis (FO) mechanism, the VRFBNM battery capacity decrease was alleviated by adding a soluble draw solute (e.g., 2-methylimidazole) into the catholyte, which can counterbalance the osmotic pressure between the positive and negative half-cell. No change of the electrolyte volume has been observed after VRFBNM being operated for 55 h, revealing that the permeation of water and vanadium ions was effectively limited. Consequently, the Coulombic efficiency (CE) of nanoporous TiO2 vanadium redox flow battery (VRFB) was enhanced from 93.5% to 95.3%, meanwhile, its capacity decay was significantly suppressed from 60.7% to 27.5% upon the addition of soluble draw solute. Moreover, the energy capacity of the VRFBNM was noticeably improved from 297.0 to 406.4 mAh remarkably. These results indicate balancing the osmotic pressure via the addition of draw solute can restrict pressure-dependent vanadium permeation and it can be established as a promising method for up-scaling VRFBNM application.

  9. [Concentrations and distribution characteristics of PCDD/Fs in spent etching solution and its copper salt recycling products].

    PubMed

    Qing, Xian; Han, Jing-Lei; Wen, Yan-Shen

    2013-02-01

    Concentrations of 17 PCDD/Fs congeners in spent etching solution and its copper salt recycling products were determined by the high resolution gas chromatography-high resolution mass spectrometry (HRGC-HRMS). The PCDD/F concentrations and corresponding WHO-TEQ (toxic equivalent quantity) values were in the range of 0-3 460 pg.L (mean= 616 pg.L-1) and 0-246 pg.L-1 (mean = 42.9 pg.L-1) , respectively, in the spent etching solution, and 1.08-24.6 ng.kg-1 (mean = 8.83 ng.kg-1) and 0.112-0.715 ng.kg-1 (mean = 0.338 ng.kg-1), respectively, in the copper salt products. The established purification treatment technique could remove most of the PCDD/Fs in the etching solution. Of the copper products, higher PCDD/F concentrations were detected in industrial products than in feed grade and plating grade products. Similar distribution characteristics were found for PCDD/ Fs in all copper salt products as the followings: 1. PCDFs were more abundant than PCDDs, 2. high chlorinated congeners were more abundant than low chlorinated congeners, except for 2,3,7,8-TCDF in the copper sulfate products.

  10. Formation of globules and aggregates of DNA chains in DNA/polyethylene glycol/monovalent salt aqueous solutions.

    PubMed

    Kawakita, H; Uneyama, T; Kojima, M; Morishima, K; Masubuchi, Y; Watanabe, H

    2009-09-07

    It has been known that giant DNA shows structural transitions in aqueous solutions under the existence of counterions and other polymers. However, the mechanism of these transitions has not been fully understood. In this study, we directly observed structures of probed (dye-labeled), dilute DNA chains in unprobed DNA/polyethylene glycol (PEG)/monovalent salt (NaCl) aqueous solutions with fluorescent microscopy to examine this mechanism. Specifically, we varied the PEG molecular weight and salt concentration to investigate the effect of competition between the depletion and electrostatic interactions on the coil-globule transition and the aggregate formation. It was found that the globules coexist with the aggregates when the unprobed DNA chains have a concentration higher than their overlap concentration. We discuss the stability of the observed structures on the basis of a free energy model incorporating the attractive depletion energy, the repulsive electrostatic energy, and the chain bending energy. This model suggested that both of the globules and aggregates are more stable than the random coil at high salt concentrations/under existence of PEG and the transition occurs when the depletion interaction overwhelms the electrostatic interaction. However, the coexistence of the globule and aggregate was not deduced from the thermodynamic model, suggesting a nonequilibrium aspect of the DNA solution and metastabilities of these structures. Thus, the population ratio of globules and aggregates was also analyzed on the basis of a kinetic model. The analysis suggested that the depletion interaction dominates this ratio, rationalizing the coexistence of globules and aggregates.

  11. Steady-state solutions of a diffusive energy-balance climate model and their stability

    NASA Technical Reports Server (NTRS)

    Ghil, M.

    1975-01-01

    A diffusive energy-balance climate model, governed by a nonlinear parabolic partial differential equation, was studied. Three positive steady-state solutions of this equation are found; they correspond to three possible climates of our planet: an interglacial (nearly identical to the present climate), a glacial, and a completely ice-covered earth. Models similar to the main one are considered, and the number of their steady states was determined. All the models have albedo continuously varying with latitude and temperature, and entirely diffusive horizontal heat transfer. The stability under small perturbations of the main model's climates was investigated. A stability criterion is derived, and its application shows that the present climate and the deep freeze are stable, whereas the model's glacial is unstable. The dependence was examined of the number of steady states and of their stability on the average solar radiation.

  12. Soft X-ray absorption spectra of aqueous salt solutions with highly charged cations in liquid microjets

    SciTech Connect

    Schwartz, Craig P.; Uejio, Janel S.; Duffin, Andrew M.; Drisdell, Walter S.; Smith, Jared D.; Saykally, Richard J.

    2010-03-11

    X-ray absorption spectra of 1M aqueous solutions of indium (III) chloride, yttrium (III) bromide, lanthanum (III) chloride, tin (IV) chloride and chromium (III) chloride have been measured at the oxygen K-edge. Relatively minor changes are observed in the spectra compared to that of pure water. SnCl{sub 4} and CrCl{sub 3} exhibit a new onset feature which is attributed to formation of hydroxide or other complex molecules in the solution. At higher energy, only relatively minor, but salt-specific changes in the spectra occur. The small magnitude of the observed spectral changes is ascribed to offsetting perturbations by the cations and anions.

  13. Photochemical aerobic detoxification of aqueous phenol and chlorophenol solutions promoted by iron salts and iron, vanadium, and copper oxides

    SciTech Connect

    Nizova, G.V.; Bochkova, M.M.; Kozlova, N.B.; Shul`pin, G.B.

    1995-09-10

    Phenol, 2,4,5-trichlorophenol, and pentachlorophenol in air in the presence of soluble iron salts or insoluble V{sub 2}O{sub 5}, Fe{sub 2}O{sub 3}, and CuO decompose in aqueous solution when irradiated by a luminescent lamp. The degree and the rate of decomposition are strongly influenced by the nature of the substrate and metal-containing promoter. As a result of decomposition, toxicity of solutions containing 2,4,5-trichlorophenol with respect to two types of living organisms - Protozoa (Tetrahymena pyriformis) and bacteria (Beneckea harveyi) - decreases significantly.

  14. Rheological and kinetic study of the ultrasonic degradation of locust bean gum in aqueous saline and salt-free solutions.

    PubMed

    Li, Ruoshi; Feke, Donald L

    2015-11-01

    The ultrasonic degradation of locust bean gum (LBG) in aqueous solutions has been studied at 25°C for ultrasonication times up to 120 min. Although LBG is not a polyelectrolyte, the degradation extent and kinetics were found to be somewhat sensitive to the ionic conditions in solution, and this is attributed to changes in molecular conformation that can occur in different salt environments. Ultrasonic degradation was tracked by rheological measurements that lead to the determination of intrinsic viscosity for the LBG molecules. A kinetic model was also developed and successfully applied to characterize and predict the degradation results.

  15. Glyoxal and Methylglyoxal Setschenow Salting Constants in Sulfate, Nitrate, and Chloride Solutions: Measurements and Gibbs Energies.

    PubMed

    Waxman, Eleanor M; Elm, Jonas; Kurtén, Theo; Mikkelsen, Kurt V; Ziemann, Paul J; Volkamer, Rainer

    2015-10-06

    Knowledge about Setschenow salting constants, KS, the exponential dependence of Henry's Law coefficients on salt concentration, is of particular importance to predict secondary organic aerosol (SOA) formation from soluble species in atmospheric waters with high salt concentrations, such as aerosols. We have measured KS of glyoxal and methylglyoxal for the atmospherically relevant salts (NH4)2SO4, NH4NO3, NaNO3, and NaCl and find that glyoxal consistently "salts-in" (KS of -0.16, -0.06, -0.065, -0.1 molality(-1), respectively) while methylglyoxal "salts-out" (KS of +0.16, +0.075, +0.02, +0.06 molality(-1)). We show that KS values for different salts are additive and present an equation for use in atmospheric models. Additionally, we have performed a series of quantum chemical calculations to determine the interactions between glyoxal/methylglyoxal monohydrate with Cl(-), NO3(-), SO4(2-), Na(+), and NH4(+) and find Gibbs free energies of water displacement of -10.9, -22.0, -22.9, 2.09, and 1.2 kJ/mol for glyoxal monohydrate and -3.1, -10.3, -7.91, 6.11, and 1.6 kJ/mol for methylglyoxal monohydrate with uncertainties of 8 kJ/mol. The quantum chemical calculations support that SO4(2-), NO3(-), and Cl(-) modify partitioning, while cations do not. Other factors such as ion charge or partitioning volume effects likely need to be considered to fully explain salting effects.

  16. Hormonal adaptation to the stresses imposed upon sodium balance by pregnancy and lactation in the Yanomama Indians: a culture without salt

    SciTech Connect

    Oliver, W.J.; Neel, J.V.; Grekin, R.J.; Cohen, E.L.

    1981-01-01

    The Yanomama Indians of northern Brazil and southern Venezuela have been identified as a no salt culture. In this study, data were obtained to determine in this population the adjustments of sodium-related hormones to the stresses imposed upon sodium balance by pregnancy and prolonged lactation. Controls against the possibility that findings in the Yanomama were ethnic rather than dietary were provided by similar observations in the Guaymi Indians of Panama, who have free access to salt. Urinary concentrations of sodium were approximately 1 mEq/l in male and female Yanomama, with 24-h excretion rates in the males averaging 1 mEq, similar to our prior observations. The pregnant Yanomama had exceeding high urinary concentrations of aldosterone. These were associated with higher plasma renin activities and serum aldosterone concentrations than in all other subjects. Although pregnant Guaymi had elevations of serum and urinary aldosterone, these were significantly lower (p < 0.001) than those of the Yanomama. Prolonged lactation in the Yanomama was associated with elevation of plasma renin activity and serum and urinary aldosterone concentration compared with the Guaymi, but were not higher than those in nonlactating Yanomama females. The findings suggest that pregnancy in a salt-poor environment is associated with an exaggerated augmentation of hormonal responses that enhance positive sodium balance.

  17. Thermoresponsive Poly(Ionic Liquid)s in Aqueous Salt Solutions: Salting-Out Effect on Their Phase Behavior and Water Absorption/Desorption Properties.

    PubMed

    Okafuji, Akiyoshi; Kohno, Yuki; Ohno, Hiroyuki

    2016-07-01

    Here, a thermoresponsive phase behavior of polymerized ionic liquids (PILs) composed of poly([tri-n-alkyl(vinylbenzyl)phosphonium]chloride) (poly([Pnnn VB ]Cl) is reported, where n (the number of carbon atoms of an alkyl chain) = 4, 5, or 6 after mixing with aqueous sodium chloride solutions. Both monomeric [P555VB ]Cl and the resulting poly([P555VB ]Cl) linear homopolymer show a lower critical solution temperature (LCST)-type phase behavior in aq. NaCl solutions. The phase transition temperature of the PIL shifts to lower value by increasing concentration of NaCl. Also the swelling degree of cross-linked poly([P555VB ]Cl) gel decreases by increasing NaCl concentration, clearly suggesting the "salting-out" effect of NaCl results in a significant dehydration of the poly([P555VB ]Cl) gel. The absorbed water in the PIL gel is desorbed by moderate heating via the LCST behavior, and the absolute absorption/desorption amount is improved by copolymerization of [P555VB ]Cl with more hydrophilic [P444VB ]Cl monomer.

  18. Insights to caving processes from localization of microseismic swarms induced by salt solution mining

    NASA Astrophysics Data System (ADS)

    Lennart Kinscher, Jannes; Bernard, Pascal; Contrucci, Isabelle; Mangeney, Anne; Piguet, Jack Pierre; Bigarre, Pascal

    2014-05-01

    In order to improve our understanding of hazardous ground failures, caving processes, and collapses of large natural or man-made underground cavities, we studied microseismicity induced by the development and collapse of a salt solution mining cavity with a diameter of ~ 200 m at Cerville-Buissoncourt in Lorraine, France. Microseismicity was recorded as part of a large geophysical, multi-parameter monitoring research project (GISOS) by a local, high resolution, triggered 40 Hz geophone monitoring system consisting of five one-component and four three-component borehole stations located around and in the center of the cavity. The recorded microseismic events are very numerous (~ 50.000 recorded event files) where the major portion (~ 80 %) appear in unusual swarming sequences constituted by complex clusters of superimposed microseismic events. Body wave phase based routine tools for microseismic event detection and localization face strong limitations in the treatment of these signals. To overcome these shortcomings, we developed two probabilistic methods being able to assess the spatio-temporal characteristics in a semi-automatic manner. The first localization approach uses simple signal amplitude estimates on different frequency bands, and an attenuation model to constrain hypocenter source location. The second approach was designed to identify significantly polarized P wave energies and the associated polarization angles. Both approaches and its probabilistic conjunction were applied to the data of a two months lasting microseismic crisis occurring one year before the final collapse that was related to caving processes leading to a maximal growth of ~ 50 m of the cavity roof. The obtained epicenter locations show systematic spatio-temporal migration trends observed for different time scales. During three phases of major swarming activity, epicenter migration trends appear in the order of several seconds to minutes, are spatially constrained, and show partially a

  19. Real-time monitoring of a salt solution mining cavern: view from microseismic and levelling monitoring

    NASA Astrophysics Data System (ADS)

    Contrucci, Isabelle; Cao, Ngoc-Tuyen; Klein, Emmanuelle; Daupley, Xavier; Bigarre, Pascal

    2010-05-01

    In 2004, in order to better understand processes involved in large-scale mine collapse, an instrumentation was settled in the surrounding of a salt cavern located at a depth of 180 m in NE France. The cavern was mined by solution mining until the large-scale ground failure occurred. A high resolution multi-parameter monitoring system was deployed in the framework of the GISOS (Scientific Interest Group on the Impact and Safety of Underground Structures formed by INERIS, BRGM, INPL and ENSG). Instrumentation, installed by INERIS, consisted of a microseismic network, coupled to automatic-measurement system for levelling (Tacheometer and RTK GPS). Quasi real time transmission of the data to INERIS, at Nancy, enabled rock mass activity of the site to be monitored on a few hours basis. Also, the various recorded observations, in the beginning of spring 2008, led the operator to cause the collapse in February 2009. This was done by intensive extraction of the brine contained in the cavern, which was considered to be at limit equilibrium. On the second day of pumping sudden increase in microseismic activity indicated the start of collapse, followed by manifestation of a surface crater about 35 hours later. All the data and information collected during this experiment are now being processed and back-analysed aimed at ensuring high quality of interpretation. In particular, the space-time distribution of the failures and the evolution of the waveforms enlighten the changing conditions in the geological overburden. When correlated with the measurements of the movement and the known geology, the microseismic data enable a precise description of the failure mechanism(s), and especially of the complex and major role of the overlying bedrock. Similarly, feedback from this experience should lead to practical recommendations concerning collapse phenomena monitoring in such a mining context. While the preliminary results already indicate the exceptional quality of this data set

  20. Ultra fast cooling of hot steel plate by air atomized spray with salt solution

    NASA Astrophysics Data System (ADS)

    Mohapatra, Soumya S.; Ravikumar, Satya V.; Jha, Jay M.; Singh, Akhilendra K.; Bhattacharya, Chandrima; Pal, Surjya K.; Chakraborty, Sudipto

    2014-05-01

    In the present study, the applicability of air atomized spray with the salt added water has been studied for ultra fast cooling (UFC) of a 6 mm thick AISI-304 hot steel plate. The investigation includes the effect of salt (NaCl and MgSO4) concentration and spray mass flux on the cooling rate. The initial temperature of the steel plate before the commencement of cooling is kept at 900 °C or above, which is usually observed as the "finish rolling temperature" in the hot strip mill of a steel plant. The heat transfer analysis shows that air atomized spray with the MgSO4 salt produces 1.5 times higher cooling rate than atomized spray with the pure water, whereas air atomized spray with NaCl produces only 1.2 times higher cooling rate. In transition boiling regime, the salt deposition occurs which causes enhancement in heat transfer rate by conduction. Moreover, surface tension is the governing parameter behind the vapour film instability and this length scale increases with increase in surface tension of coolant. Overall, the achieved cooling rates produced by both types of salt added air atomized spray are found to be in the UFC regime.

  1. The role of the binding salt sodium salicylate in semidilute ionic cetylpyridinium chloride micellar solutions: a rheological and scattering study.

    PubMed

    Gaudino, D; Pasquino, R; Stellbrink, J; Szekely, N; Krutyeva, M; Radulescu, A; Pyckhout-Hintzen, W; Grizzuti, N

    2016-12-21

    The micellar system based on cetylpyridinium chloride (CPyCl) and sodium salicylate (NaSal) in brine solution is investigated on both macro- and micro-length scales through rheology and scattering measurements. The linear viscoelasticity of the system and its structural parameters are explored by systematically changing the amount of NaSal over an extremely wide range of concentrations, thus producing salt-to-surfactant molar ratios from zero to about 8.5. As a result, the well-known non-monotonic behaviour of the zero-shear rate viscosity as a function of salinity can be connected to micellar morphological changes, whose driving force is represented by the simultaneous binding and screening actions of NaSal. The viscosity behaviour can be seen as a direct consequence of consecutive lengthening/shortening of the contour length, where the micelles attempt to minimize the electrostatic charge density on their surface. Along similar lines, the scattering measurements of the semidilute solutions show that the local stiffness of the micellar chain changes with increasing salt content influencing the elasticity of the resulting network. Within this general view, the branching of the micelles can be seen as a side effect attributable to the main character of the play, namely, the binding salt NaSal, whereas the overall dynamics of the system is driven by the considerable changes in the entanglement density of the micellar network.

  2. Ion aggregation in high salt solutions. IV. Graph-theoretical analyses of ion aggregate structure and water hydrogen bonding network

    NASA Astrophysics Data System (ADS)

    Choi, Jun-Ho; Cho, Minhaeng

    2015-09-01

    Ions in high salt solutions form a variety of ion aggregates, from ion pairs to clusters and networks. Their influences on water hydrogen bonding (H-bonding) network structures have long been of great interest. Recently, we have shown that the morphological structures of ion aggregates can be analyzed by using a spectral graph analysis theory, where each ion cluster or ion network is represented by a properly defined graph with edges and vertices. Here, to further examine the network properties of ion aggregates and water H-bonding networks in high salt solutions, we consider a few representative graph-theoretical descriptors: clustering coefficient, minimum path length, global efficiency, and degree distribution of ion aggregates. From the molecular dynamics trajectories, these graph theoretical properties of ion aggregates and water structures in NaCl and kosmotropic solutions are calculated and shown to be strongly dependent on the two types of ion aggregate structures, i.e., ion cluster and ion network. Ion clusters in high NaCl solutions exhibit typical behaviors of scale free network. The corresponding graph theoretical properties of ion networks in high KSCN solutions are notably different from those of NaCl ion clusters and furthermore they are very similar to those of water hydrogen-bonding network. The present graph-theoretical analysis results indicate that the high solubility limits of KSCN and other ion-network-forming salts might originate from their ability to form a large scale morphological network that can be intertwined with co-existing water H-bonding network. Furthermore, it is shown that the graph-theoretical properties of water H-bonding network structures do not strongly depend on the nature of dissolved ions nor on the morphological structures of ion aggregates, indicating that water's H-bonding interaction and network-forming capability are highly robust. We anticipate that the present graph-theoretical analysis results of high salt

  3. Ion aggregation in high salt solutions. IV. Graph-theoretical analyses of ion aggregate structure and water hydrogen bonding network.

    PubMed

    Choi, Jun-Ho; Cho, Minhaeng

    2015-09-14

    Ions in high salt solutions form a variety of ion aggregates, from ion pairs to clusters and networks. Their influences on water hydrogen bonding (H-bonding) network structures have long been of great interest. Recently, we have shown that the morphological structures of ion aggregates can be analyzed by using a spectral graph analysis theory, where each ion cluster or ion network is represented by a properly defined graph with edges and vertices. Here, to further examine the network properties of ion aggregates and water H-bonding networks in high salt solutions, we consider a few representative graph-theoretical descriptors: clustering coefficient, minimum path length, global efficiency, and degree distribution of ion aggregates. From the molecular dynamics trajectories, these graph theoretical properties of ion aggregates and water structures in NaCl and kosmotropic solutions are calculated and shown to be strongly dependent on the two types of ion aggregate structures, i.e., ion cluster and ion network. Ion clusters in high NaCl solutions exhibit typical behaviors of scale free network. The corresponding graph theoretical properties of ion networks in high KSCN solutions are notably different from those of NaCl ion clusters and furthermore they are very similar to those of water hydrogen-bonding network. The present graph-theoretical analysis results indicate that the high solubility limits of KSCN and other ion-network-forming salts might originate from their ability to form a large scale morphological network that can be intertwined with co-existing water H-bonding network. Furthermore, it is shown that the graph-theoretical properties of water H-bonding network structures do not strongly depend on the nature of dissolved ions nor on the morphological structures of ion aggregates, indicating that water's H-bonding interaction and network-forming capability are highly robust. We anticipate that the present graph-theoretical analysis results of high salt

  4. On the appearance of vorticity and gradient shear bands in wormlike micellar solutions of different CPCl/salt systems

    SciTech Connect

    Mütze, Annekathrin Heunemann, Peggy; Fischer, Peter

    2014-11-01

    Wormlike micellar salt/surfactant solutions (X-salicylate, cetylpyridinium chloride) are studied with respect to the applied shear stress, concentration, temperature, and composition of the counterions (X = lithium, sodium, potassium, magnesium, and calcium) of the salicylate salt solute to determine vorticity and gradient shear bands. A combination of rheological measurements, laser technique, video analysis, and rheo-small-angle neutron scattering allow for a detailed exploration of number and types of shear bands. Typical flow curves of the solutions show Newtonian, shear-thinning, and shear-thickening flow behavior. In the shear-thickening regime, the solutions show vorticity and gradient shear bands simultaneously, in which vorticity shear bands dominate the visual effect, while gradient shear bands always coexist and predominate the rheological response. It is shown that gradient shear bands change their phases (turbid, clear) with the same frequency as the shear rate oscillates, whereas vorticity shear bands change their phases with half the frequency of the shear rate. Furthermore, we show that with increasing molecular mass of the counterions the number of gradient shear bands increases, while the number of vorticity shear bands remains constant. The variation of temperature, shear stress, concentration, and counterions results in a predictable change in the rheological behavior and therefore allows adjustment of the number of vorticity shear bands in the shear band regime.

  5. Bathing in a magnesium-rich Dead Sea salt solution improves skin barrier function, enhances skin hydration, and reduces inflammation in atopic dry skin.

    PubMed

    Proksch, Ehrhardt; Nissen, Hans-Peter; Bremgartner, Markus; Urquhart, Colin

    2005-02-01

    Magnesium salts, the prevalent minerals in Dead Sea water, are known to exhibit favorable effects in inflammatory diseases. We examined the efficacy of bathing atopic subjects in a salt rich in magnesium chloride from deep layers of the Dead Sea (Mavena(R) Dermaline Mg(46) Dead Sea salt, Mavena AG, Belp, Switzerland). Volunteers with atopic dry skin submerged one forearm for 15 min in a bath solution containing 5% Dead Sea salt. The second arm was submerged in tap water as control. Before the study and at weeks 1-6, transepidermal water loss (TEWL), skin hydration, skin roughness, and skin redness were determined. We found one subgroup with a normal and one subgroup with an elevated TEWL before the study. Bathing in the Dead Sea salt solution significantly improved skin barrier function compared with the tap water-treated control forearm in the subgroup with elevated basal TEWL. Skin hydration was enhanced on the forearm treated with the Dead Sea salt in each group, which means the treatment moisturized the skin. Skin roughness and redness of the skin as a marker for inflammation were significantly reduced after bathing in the salt solution. This demonstrates that bathing in the salt solution was well tolerated, improved skin barrier function, enhanced stratum corneum hydration, and reduced skin roughness and inflammation. We suggest that the favorable effects of bathing in the Dead Sea salt solution are most likely related to the high magnesium content. Magnesium salts are known to bind water, influence epidermal proliferation and differentiation, and enhance permeability barrier repair.

  6. Formation of Gaseous Bromine From the Photolysis of Nitrate and Hydrogen Peroxide in Sea-Salt Solutions

    NASA Astrophysics Data System (ADS)

    George, I.; Anastasio, C.

    2003-12-01

    The formation of reactive halogen gases in sea-salt particles can play a significant role in chemistry within the marine boundary layer (MBL). While there have been several proposed mechanisms for the formation of reactive halogens in sea-salt particles, we were interested in whether hydroxyl radical (ṡOH) generated within the particles themselves could lead to release of gaseous reactive bromine species (Br*(g)). To examine this question, we illuminated (313 nm) solutions of chloride and bromide that contained either nitrate or hydrogen peroxide as a photochemical source of ṡOH. Experiments were performed either in concentrated seawater or in laboratory solutions with halide concentrations that in most experiments were typical for deliquesced, aged sea-salt particles (e.g., 3.5 M Cl-, 5.0 mM Br-, 100 mM NO3-, and pH 4). During illumination we bubbled air through the solutions and collected the released gaseous reactive bromine in downstream bubblers or denuders. We found that gaseous bromide was nearly always released during the illumination of solutions containing either nitrate (100 mM) or hydrogen peroxide (1.0 mM). In order to gain insight into the mechanisms for these reactions, we studied the effects of several factors on the rate of release of gaseous bromine. For example, the release of Br*(g) was enhanced in solutions at lower pH, and this pH-dependent trend was similar in both the nitrate and hydrogen peroxide systems. In solutions containing bromide and nitrate at a fixed ionic strength, the addition of chloride showed little effect on the Br*(g) release, while increasing ionic strength significantly slowed down its release. In hydrogen peroxide solutions, however, the presence of chloride strongly enhanced Br*(g) release, while the ionic strength of the solution was shown to have no effect on the reaction. Furthermore, the Br*(g) formation rate increased rapidly with bromide concentration in nitrate solutions containing 0 - 2 mM Br-, but was

  7. Analytical Solutions to the Near-Neutral Atmospheric Surface Energy Balance with and without Heat Storage for Urban Climatological Studies.

    NASA Astrophysics Data System (ADS)

    Tso, C. P.; Chan, B. K.; Hashim, M. A.

    1991-04-01

    Analytical solutions are presented to the near-neutral atmospheric surface energy balance with the new approach of including the participation of heat storage in the building substrate. Analytical solutions are also presented for the first time for the case without heat storage effect. By a linearization process, the governing equations are simplified to a set of time-dependent, linear, first-order equations from which explicit solutions are readily obtainable. The results compare well with those obtained by numerical solutions upon the set without linearization when applied to the tropical city of Kuala Lumpur, Malaysia.

  8. Thermodynamic properties of ibuprofen sodium salt in aqueous/urea micellar solutions at 298.15 K

    NASA Astrophysics Data System (ADS)

    Azum, Naved; Asiri, Abdullah M.; Rub, Malik Abdul; Al-Youbi, Abdulrahman O.

    2017-04-01

    Thermodynamic, surface and micellar properties of anti-inflammatory drug sodium 2-(4-isobutylphenyl) propionate (sodium salt of ibuprofen (NaIBF)) in aqueous/urea solution were studied by surface tension measurements at 298.15 K in the presence of anionic surfactant sodium dodecylsulfate (SDS). Critical micelle concentration ( cmc), surface tension at cmc (γ cmc), maximum Gibbs surface excess (Γmax), minimum surface area per surfactant molecule at the air/water interface ( A min) etc. were determined in pure water as well as in aqueous urea solution. The theories of Clint, Rosen and Rubingh have been applied to describe the interactions between these amphiphiles at the interface and in the micellar solution. Various thermodynamic parameters have been calculated and discussed in detail.

  9. Molecular-scale Hydrophilicity Induced by Solute: Molecular-thick Charged Pancakes of Aqueous Salt Solution on Hydrophobic Carbon-based Surfaces

    PubMed Central

    Shi, Guosheng; Shen, Yue; Liu, Jian; Wang, Chunlei; Wang, Ying; Song, Bo; Hu, Jun; Fang, Haiping

    2014-01-01

    We directly observed molecular-thick aqueous salt-solution pancakes on a hydrophobic graphite surface under ambient conditions employing atomic force microscopy. This observation indicates the unexpected molecular-scale hydrophilicity of the salt solution on graphite surfaces, which is different from the macroscopic wetting property of a droplet standing on the graphite surface. Interestingly, the pancakes spontaneously displayed strong positively charged behavior. Theoretical studies showed that the formation of such positively charged pancakes is attributed to cation–π interactions between Na+ ions in the aqueous solution and aromatic rings on the graphite surface, promoting the adsorption of water molecules together with cations onto the graphite surface; i.e., Na+ ions as a medium adsorbed to the graphite surface through cation–π interactions on one side while at the same time bonding to water molecules through hydration interaction on the other side at a molecular scale. These findings suggest that actual interactions regarding carbon-based graphitic surfaces including those of graphene, carbon nanotubes, and biochar may be significantly different from existing theory and they provide new insight into the control of surface wettability, interactions and related physical, chemical and biological processes. PMID:25348642

  10. [Evaluation of the efficiency of balanced and unbalanced crystalloid solutions used in the program of infusion therapy in patients with blood loss].

    PubMed

    Lukach, V N; Girsh, A O; Stukanov, M M; Glushchenko, A V

    2009-01-01

    The authors present a comparative assessment of the efficiency of balanced and unbalanced crystalloid solutions used in the program of infusion therapy in patients with blood loss. It was found that infusion therapy with unbalanced crystalloid solution facilitated the appearance of electrolytic changes and decrease of pH of venous blood while infusion therapy with balanced crystalloid solution did not cause negative changes of the water-electrolytic and acid-base balance.

  11. RESULTS OF ROUTINE STRIP EFFLUENT HOLD TANK AND DECONTAMINATED SALT SOLUTION HOLD TANK SAMPLES FROM MODULAR CAUSTIC-SIDE SOLVENT EXTRACTION UNIT DURING MACROBATCH 3 OPERATIONS

    SciTech Connect

    Peters, T.; Fink, S.

    2011-06-10

    Strip Effluent Hold Tank (SEHT) and Decontaminated Salt Solution Hold Tank (DSSHT) samples from several of the 'microbatches' of Integrated Salt Disposition Project (ISDP) Salt Batch ('Macrobatch') 3 have been analyzed for {sup 238}Pu, {sup 90}Sr, {sup 137}Cs, and by Inductively Coupled Plasma Emission Spectroscopy (ICPES). The results indicate good decontamination performance within process design expectations. While the data set is sparse, the results of this set and the previous set of results for Macrobatch 3 samples indicate consistent operations. However, the Decontamination Factors for plutonium and strontium removal have declined in Macrobatch 3, compared to Macrobatch 2. This may be due to the differences in the Pu concentration or the bulk chemical concentrations in the feed material. SRNL is considering the possible reasons for this decline. The DSSHT samples show continued presence of titanium, likely from leaching of the monosodium titanate in ARP. During operation of the ISDP, quantities of salt waste are processed through the Actinide Removal Process (ARP) and MCU in batches of {approx}3800 gallons. Monosodium titanate (MST) is used in ARP to adsorb actinides and strontium from the salt waste and the waste slurry is then filtered prior to sending the clarified salt solution to MCU. The MCU uses solvent extraction technology to extract cesium from salt waste and concentrate cesium in an acidic aqueous stream (Strip Effluent - SE), leaving a decontaminated caustic salt aqueous stream (Decontaminated Salt Solution - DSS). Sampling occurs in the Decontaminated Salt Solution Hold Tank (DSSHT) and Strip Effluent Hold Tank (SEHT) in the MCU process. The MCU sample plan requires that batches be sampled and analyzed for plutonium and strontium content by Savannah River National Lab (SRNL) to determine MST effectiveness. The cesium measurement is used to monitor cesium removal effectiveness and the inductively coupled plasma emission spectroscopy (ICPES) is

  12. A scaled-ionic-charge simulation model that reproduces enhanced and suppressed water diffusion in aqueous salt solutions.

    PubMed

    Kann, Z R; Skinner, J L

    2014-09-14

    Non-polarizable models for ions and water quantitatively and qualitatively misrepresent the salt concentration dependence of water diffusion in electrolyte solutions. In particular, experiment shows that the water diffusion coefficient increases in the presence of salts of low charge density (e.g., CsI), whereas the results of simulations with non-polarizable models show a decrease of the water diffusion coefficient in all alkali halide solutions. We present a simple charge-scaling method based on the ratio of the solvent dielectric constants from simulation and experiment. Using an ion model that was developed independently of a solvent, i.e., in the crystalline solid, this method improves the water diffusion trends across a range of water models. When used with a good-quality water model, e.g., TIP4P/2005 or E3B, this method recovers the qualitative behaviour of the water diffusion trends. The model and method used were also shown to give good results for other structural and dynamic properties including solution density, radial distribution functions, and ion diffusion coefficients.

  13. Preparation of porous monolayer film by immersing the stearic acid Langmuir-Blodgett monolayer on mica in salt solution

    NASA Astrophysics Data System (ADS)

    Wang, S.; Li, Y. L.; Zhao, H. L.; Liang, H.; Liu, B.; Pan, S.

    2012-11-01

    Porous materials have drawn attention from scientists in many fields such as life sciences, catalysis and photonics since they can be used to induce some materials growth as expected. Especially, porous Langmuir-Blodgett (LB) film is an ideal material with controlled thickness and flat surface. In this paper, stearic acid (SA), which has been extensively explored in LB film technique, is chosen as the template material with known parameters to prepare the LB film, and then the porous SA monolayer film is obtained by means of etching in salt solution. The main etching mechanism is suggested that the cations in the solution block the electrostatic interaction between the polar carboxyl group of SA and the electronegative mica surface. The influencing factors (such as concentration of salt solution, valence of cation and surface pressure) of the porous SA film are systematically studied in this work. The novel method proposed in this paper makes it convenient to prepare porous monolayer film for designed material growth or cell culture.

  14. History and future of human cadaver preservation for surgical training: from formalin to saturated salt solution method.

    PubMed

    Hayashi, Shogo; Naito, Munekazu; Kawata, Shinichi; Qu, Ning; Hatayama, Naoyuki; Hirai, Shuichi; Itoh, Masahiro

    2016-01-01

    Traditionally, surgical training meant on-the-job training with live patients in an operating room. However, due to advancing surgical techniques, such as minimally invasive surgery, and increasing safety demands during procedures, human cadavers have been used for surgical training. When considering the use of human cadavers for surgical training, one of the most important factors is their preservation. In this review, we summarize four preservation methods: fresh-frozen cadaver, formalin, Thiel's, and saturated salt solution methods. Fresh-frozen cadaver is currently the model that is closest to reality, but it also presents myriad problems, including the requirement of freezers for storage, limited work time because of rapid putrefaction, and risk of infection. Formalin is still used ubiquitously due to its low cost and wide availability, but it is not ideal because formaldehyde has an adverse health effect and formalin-embalmed cadavers do not exhibit many of the qualities of living organs. Thiel's method results in soft and flexible cadavers with almost natural colors, and Thiel-embalmed cadavers have been appraised widely in various medical disciplines. However, Thiel's method is relatively expensive and technically complicated. In addition, Thiel-embalmed cadavers have a limited dissection time. The saturated salt solution method is simple, carries a low risk of infection, and is relatively low cost. Although more research is needed, this method seems to be sufficiently useful for surgical training and has noteworthy features that expand the capability of clinical training. The saturated salt solution method will contribute to a wider use of cadavers for surgical training.

  15. Salt Stress-Induced Changes in the Transcriptome, Compatible Solutes, and Membrane Lipids in the Facultatively Phototrophic Bacterium Rhodobacter sphaeroides▿†

    PubMed Central

    Tsuzuki, Minoru; Moskvin, Oleg V.; Kuribayashi, Masayuki; Sato, Kiichi; Retamal, Susana; Abo, Mitsuru; Zeilstra-Ryalls, Jill; Gomelsky, Mark

    2011-01-01

    Responses to NaCl stress were investigated in phototrophically grown Alphaproteobacterium Rhodobacter sphaeroides by transcriptome profiling, mutational analysis, and measurements of compatible solutes and membrane phospholipids. After exposure to salt stress, genes encoding two putative glycine betaine uptake systems, proVWX and betS, were highly upregulated. Mutational analysis revealed that BetS, not ProVWX, was the primary transporter of this compatible solute. Upon the addition of salt, exogenous glycine betaine was taken up rapidly, and maximal intracellular levels were reached within minutes. In contrast, synthesis of another important compatible solute in R. sphaeroides, trehalose, increased slowly following salt stress, reaching maximal levels only after several hours. This accumulation pattern was consistent with the more gradual increase in salt-induced transcription of the trehalose biosynthesis operon otsBA. Several genes encoding putative transcription factors were highly induced by salt stress. Multiple copies of one of these factors, crpO (RSP1275), whose product is a member of the cyclic AMP receptor protein/fumarate and nitrate reduction regulator (CRP/FNR) family, improved NaCl tolerance. When crpO was provided in multicopy, expression of genes for synthesis or transport of compatible solutes was unaltered, but the membrane phospholipid composition became biased toward that found in salt-stressed cells. Collectively, this study characterized transcriptional responses to salt stress, correlated changes in transcription with compatible solute accumulation rates, identified the main glycine betaine transporter and trehalose synthase, characterized salt-induced changes in phospholipid composition, and uncovered a transcription factor associated with changes in phospholipids. These findings set the stage for deciphering the salt stress-responsive regulatory network in R. sphaeroides. PMID:21908636

  16. Experimental determination of Henry's law constants of difluoromethane (HFC-32) and the salting-out effects in aqueous salt solutions relevant to seawater

    NASA Astrophysics Data System (ADS)

    Kutsuna, Shuzo

    2017-06-01

    Gas-to-water equilibrium coefficients, KeqS (in M atm-1), of difluoromethane (CH2F2), a hydrofluorocarbon refrigerant (HFC-32), in aqueous salt solutions relevant to seawater were determined over a temperature (T) range from 276 to 313 K and a salinity (S) range up to 51 ‰ by means of an inert-gas stripping method. From the van't Hoff equation, the KeqS value in water, which corresponds to the Henry's law constant (KH), at 298 K was determined to be 0.065 M atm-1. The salinity dependence of KeqS (the salting-out effect), ln(KH/KeqS), did not obey the Sechenov equation but was proportional to S0. 5. Overall, the KeqS(T) value was expressed by ln(KeqS(T)) = -49.71 + (77.70 - 0.134 × S0. 5) × (100/T) + 19.14 × ln(T/100). By using this equation in a lower-tropospheric semi-hemisphere (30-90 °S) of the Advanced Global Atmospheric Gases Experiment (AGAGE) 12-box model, we estimated that 1 to 4 % of the atmospheric burden of CH2F2 resided in the ocean mixed layer and that this percentage was at least 4 % in the winter; dissolution of CH2F2 in the ocean may partially influence estimates of CH2F2 emissions from long-term observational data of atmospheric CH2F2 concentrations.

  17. An adiabatic linearized path integral approach for quantum time correlation functions: electronic transport in metal-molten salt solutions.

    PubMed

    Causo, Maria Serena; Ciccotti, Giovanni; Montemayor, Daniel; Bonella, Sara; Coker, David F

    2005-04-14

    We generalize the linearized path integral approach to evaluate quantum time correlation functions for systems best described by a set of nuclear and electronic degrees of freedom, restricting ourselves to the adiabatic approximation. If the operators in the correlation function are nondiagonal in the electronic states, then this adiabatic linearized path integral approximation for the thermal averaged quantum dynamics presents interesting and distinctive features, which we derive and explore in this paper. The capability of these approximations to accurately reproduce the behavior of physical systems is demonstrated by calculating the diffusion constant for an excess electron in a metal-molten salt solution.

  18. Multilayered Thin Metal Film Deposition by Sequential Operation of Nanosilicon Electron Emitter in Metal-Salt Solutions

    NASA Astrophysics Data System (ADS)

    Ohta, Toshiyuki; Gelloz, Bernard; Koshida, Nobuyoshi

    2011-06-01

    The use of a nanocrystalline silicon (nc-Si) ballistic electron emitter in metal-salt solutions induces the deposition of thin metal films. The nc-Si emitter is composed of a thin Au/Ti film, an anodized polycrystalline Si layer, and an n+-Si substrate. When the emitter is driven in NiCl2, CoSO4, and ZnSO4 solutions without using any counter electrodes, thin Ni, Co, and Zn films are deposited on the emission area, respectively, as well as a thin Cu film in CuSO4 solution. According to cyclic voltammogram measurements under a standard three-electrode configuration, the hot electron injection effect into the solution is clearly observed in all cases at potentials within the electrochemical window, in which no electrolytic reactions occur. Energetic electrons injected into the solutions cause the direct reduction of metal ions. As a possible application, the multilayered deposition of different metals is demonstrated by sequential operation in NiCl2 and CuSO4 solutions.

  19. Salting effects on protein components in aqueous NaCl and urea solutions: toward understanding of urea-induced protein denaturation.

    PubMed

    Li, Weifeng; Zhou, Ruhong; Mu, Yuguang

    2012-02-02

    The mechanism of urea-induced protein denaturation is explored through studying the salting effect of urea on 14 amino acid side chain analogues, and N-methylacetamide (NMA) which mimics the protein backbone. The solvation free energies of the 15 molecules were calculated in pure water, aqueous urea, and NaCl solutions. Our results show that NaCl displays strong capability to salt out all 15 molecules, while urea facilitates the solvation (salting-in) of all the 15 molecules on the other hand. The salting effect is found to be largely enthalpy-driven for both NaCl and urea. Our observations can explain the higher stability of protein's secondary and tertiary structures in typical salt solutions than that in pure water. Meanwhile, urea's capability to better solvate protein backbone and side-chain components can be extrapolated to explain protein's denaturation in aqueous urea solution. Urea salts in molecules through direct binding to solute surface, and the strength is linearly dependent on the number of heavy atoms of solute molecules. The van der Waals interactions are found to be the dominant force, which challenges a hydrogen-bonding-driven mechanism proposed previously.

  20. Depletion and double layer forces acting between charged particles in solutions of like-charged polyelectrolytes and monovalent salts.

    PubMed

    Moazzami-Gudarzi, Mohsen; Maroni, Plinio; Borkovec, Michal; Trefalt, Gregor

    2017-05-14

    Interaction forces between silica particles were measured in aqueous solutions of the sodium salt of poly(styrene sulphonate) (PSS) and NaCl using the colloidal probe technique based on an atomic force microscope (AFM). The observed forces can be rationalized through a superposition of damped oscillatory forces and double layer forces quantitatively. The double layer forces are modeled using Poisson-Boltzmann (PB) theory for a mixture of a monovalent symmetric electrolyte and a highly asymmetric electrolyte, whereby the multivalent coions represent the polyelectrolyte chains. The effective charge of the polyelectrolyte is found to be smaller than the bare number of charged groups residing on one polyelectrolyte molecule. This effect can be explained by counterion condensation. The interplay between depletion and double layer forces can be further used to predict the phase of the depletion force oscillations. However, this picture holds only at not too elevated concentrations of the polyelectrolyte and salt. At higher salt concentrations, attractive van der Waals forces become important, while at higher polyelectrolyte concentrations, the macromolecules adsorb onto the like-charged silica interface.

  1. Effect of monovalent-divalent cation exchange on the swelling of polyacrylate hydrogels in physiological salt solutions.

    PubMed

    Horkay, F; Tasaki, I; Basser, P J

    2001-01-01

    The volume transition induced by monovalent-divalent cation exchange of fully neutralized polyacrylate hydrogels was investigated in aqueous NaCl solutions. The variation of the osmotic swelling pressure, shear modulus, and mixing pressure was measured when Na(+) ions were substituted by divalent or trivalent cations. Alkali metal salts move freely throughout the entirely network, and alkaline earth metal salts (CaCl(2), SrCl(2)) promote aggregation of polyacrylate chains, but these aggregates are relatively weak. Transition metal salts (CoCl(2), NiCl(2)) form stronger interchain associates. Rare earth cations (La(3+) and Ce(3+)) bind practically irreversibly to the polymer. Experimental data indicate that transition metal cations modify both the elastic and mixing components of the free energy, while alkaline earth metal cations affect primarily the mixing term. The behavior of freely swollen gels was compared with similar gels subjected to uniaxial compression. In uniaxially compressed gels, volume transition occurs at lower cation concentrations than in the corresponding undeformed gels. The shift of the transition point increases with the deformation ratio and is larger for Co(2+) than for Ca(2+).

  2. Nuclear Magnetic Resonance Studies of Aluminosilicate Gels Prepared in High-Alkaline and Salt-Concentrated Solutions

    SciTech Connect

    Wang, Li Q.; Mattigod, Shas V.; Parker, Kent E.; Hobbs, David T.; McCready, David E.

    2005-11-01

    Solid-state 29Si, 27Al, and 23Na MAS (magic angle spinning) NMR techniques in combination with x-ray powder diffraction (XRD) are used to characterize aluminosilicate gels as a function of composition, pH, and reaction times. These gels were prepared at 80 C using initial solutions with low Si/Al ratios, high alkaline and salt concentrations that are characteristic of nuclear tank wastes. XRD data show that cancrinite and sodalite are the main crystalline phases in the aluminosilicate gels produced. It is found that the pH and the salt content have significant effects on the nature of the aluminosilicate gels. Higher pH appears to increase the rate of crystallization, the degree of overall crystallinity and the percentage of cancrinite phases in aluminosilicate gels, whereas the high salt concentration promotes the formation of cancrinite and sodalite and prohibits the formation of other zeolites. Complementary to XRD, NMR is extremely useful for providing the information on the structure of amorphous intermediate gels with no long-range order.

  3. Potassium isotope fractionation between K-salts and saturated aqueous solutions at room temperature: Laboratory experiments and theoretical calculations

    NASA Astrophysics Data System (ADS)

    Li, Weiqiang; Kwon, Kideok D.; Li, Shilei; Beard, Brian L.

    2017-10-01

    Improvements in mass spectrometry have made it possible to identify naturally occurring K isotope (39K/41K) variability in terrestrial samples that can be used in a variety of geological and biological applications that involve cycling of K such as clay or evaporite formation. However, our ability to interpret K isotope variability is limited by a poor understanding of how K isotopes are fractionated at low temperatures. In this study, we conducted recrystallization experiments of eight K-salts in order to measure the K isotope fractionation factor between the salt and the saturated K solution (Δ41Kmin-sol). Measured Δ41Kmin-sol are +0.50‰ for K2CO3·1.5H2O, +0.32‰ for K2SO4, +0.23‰ for KHCO3, +0.06‰ for K2C2O4·H2O, +0.02‰ for KCl, -0.03‰ for K2CrO4, -0.15‰ for KBr, and -0.52‰ for KI. Overall the Δ41Kmin-sol decreases with increasing r for K in crystals, where r is the average distance between a K atom and its neighboring atoms of negative charge. Salts with monovalent anions and salts with divalent anion complexes define different linear trends with distinct slopes on a plot of Δ41Kmin-sol - r. We applied ab initio lattice dynamics and empirical crystal-chemistry models to calculation of K isotope fractionation factors between K salts; both methods showed that the calculated inter-mineral K isotope fractionation factors (Δ41Kmin-KCl) are highly consistent with experimentally derived Δ41Kmin-KCl under the assumption of consistent β factors for different saturated K solutions. Formulations for the crystal-chemistry model further indicate that both anion charge and bond length r are the principle controlling factors for K isotope fractionation, and the K isotope fractionation factors correlate with r following a 1/r3 relationship. Our experiment and theoretical study confirms the existence of significant equilibrium K isotope fractionation at ambient conditions, and the K isotope fractionation factors for halides and sulfate obtained in this

  4. Spiropyran salts and their neutral precursors: synthesis, crystal structure, photochromic transformations in solutions and solid state

    NASA Astrophysics Data System (ADS)

    Yurieva, E. A.; Aldoshin, S. M.

    2015-06-01

    This review covers investigations of spiropyran iodides with N-substituted indoline fragment, and with the pyran cycle being annelated to N-methylated pyridine ring. The schemes of synthesis of iodides and their neutral precursors, as well as results of X-ray analysis and photochemical study of the crystals of the obtained compounds are presented. Based on our and literature data, the relationship between the structure and photochromic properties has been discussed for a series of salts and neutral pyridospiropyrans.

  5. Microbially Mediated Plant Salt Tolerance and Microbiome-based Solutions for Saline Agriculture.

    PubMed

    Qin, Yuan; Druzhinina, Irina S; Pan, Xueyu; Yuan, Zhilin

    2016-11-15

    Soil salinization adversely affects plant growth and has become one of the major limiting factors for crop productivity worldwide. The conventional approach, breeding salt-tolerant plant cultivars, has often failed to efficiently alleviate the situation. In contrast, the use of a diverse array of microorganisms harbored by plants has attracted increasing attention because of the remarkable beneficial effects of microorganisms on plants. Multiple advanced '-omics' technologies have enabled us to gain insights into the structure and function of plant-associated microbes. In this review, we first focus on microbe-mediated plant salt tolerance, in particular on the physiological and molecular mechanisms underlying root-microbe symbiosis. Unfortunately, when introducing such microbes as single strains to soils, they are often ineffective in improving plant growth and stress tolerance, largely due to competition with native soil microbial communities and limited colonization efficiency. Rapid progress in rhizosphere microbiome research has revived the belief that plants may benefit more from association with interacting, diverse microbial communities (microbiome) than from individual members in a community. Understanding how a microbiome assembles in the continuous compartments (endosphere, rhizoplane, and rhizosphere) will assist in predicting a subset of core or minimal microbiome and thus facilitate synthetic re-construction of microbial communities and their functional complementarity and synergistic effects. These developments will open a new avenue for capitalizing on the cultivable microbiome to strengthen plant salt tolerance and thus to refine agricultural practices and production under saline conditions.

  6. Bupivacaine salts of diflunisal and other aromatic hydroxycarboxylic acids: aqueous solubility and release characteristics from solutions and suspensions using a rotating dialysis cell model.

    PubMed

    Østergaard, Jesper; Larsen, Susan W; Parshad, Henrik; Larsen, Claus

    2005-11-01

    In the search for poorly soluble bupivacaine salts potentially enabling prolonged postoperative pain relief after local joint administration in the form of suspensions the solubility of bupivacaine salts of diflunisal and other aromatic hydroxycarboxylic acids were investigated together with the release characteristics of selected 1:1 salts from solutions and suspensions using a rotating dialysis cell model. The poorest soluble bupivacaine salts were obtained from the aromatic ortho-hydroxycarboxylic acids diflunisal, 5-iodosalicylic acid, and salicylic acid (aqueous solubilities: 0.6-1.9 mM at 37 degrees C). Diffusant appearance rates in the acceptor phase upon instillation of solutions of various salts in the donor cell applied to first-order kinetics. Calculated permeability coefficients for bupivacaine and the counterions diflunisal, 5-iodosalicylic acid, and mandelic acid were found to be correlated with the molecular size of the diffusants. Release experiments at physiological pH involving suspensions of the bupivacaine-diflunisal salt revealed that at each sampling point the diflunisal concentration exceeded that of bupivacaine in the acceptor phase. However, after an initial lag period, a steady state situation was attained resulting in equal and constant fluxes of the two diffusants controlled by the permeability coefficients in combination with the solubility product of the salt. Due to the fact that the saturation solubility of the bupivacaine-salicylic acid salt in water exceeded that of bupivacaine at pH 7.4, suspensions of the latter salt were unable to provide simultaneous release of the cationic and anionic species at pH 7.4. The release profiles were characterised by a rapid release of salicylate accompanied by a much slower appearance of bupivacaine in the acceptor phase caused by precipitation of bupivacaine base from the solution upon dissolution of the salt in the donor cell.

  7. Concentration of source terms in generalized Glimm scheme for global entropy solutions of nonlinear hyperbolic balance laws

    NASA Astrophysics Data System (ADS)

    Chou, Shih-Wei; Lin, Ying-Chieh

    2017-08-01

    In this paper, we investigate the Cauchy problem for a nonlinear hyperbolic system of balance laws with sources ax g and at h. To get the approximate solutions of our problem, we consider a version of generalized Riemann problem that concentrates the variation of a on a thin T-shaped region of each grid. A new version of Glimm scheme is introduced to construct the approximate solutions and its stability is proved by considering two types of conditions on a. Finally, we verify the consistency of the scheme and the entropy inequality to establish the global existence of entropy solutions.

  8. Lorentz force on sodium and chlorine ions in a salt water solution flow under a transverse magnetic field

    NASA Astrophysics Data System (ADS)

    DeLuca, R.

    2009-05-01

    It is shown that, by applying elementary concepts in electromagnetism and electrochemistry to a system consisting of salt water flowing in a thin rectangular pipe at an average velocity vA under the influence of a transverse magnetic field B0, an electromotive force generator can be conceived. In fact, the Lorentz force acting on the sodium and chlorine ions in a water solution gives rise to a so-called Faraday voltage across the two metal electrodes, positioned at the sides of the pipe. The effect is carried along the following chemical reactions at the electrodes: at the cathode, water is reduced (instead of sodium ions) and hydrogen gas is generated; at the anode, chlorine gas is produced. In college physics teaching, this interdisciplinary subject can be adopted to stress analogies and differences between the Hall voltage in conductors and the Faraday voltage in electrolyte solutions.

  9. Solution-based approaches for making high-density sodalite waste forms to immobilize spent electrochemical salts

    NASA Astrophysics Data System (ADS)

    Lepry, William C.; Riley, Brian J.; Crum, Jarrod V.; Rodriguez, Carmen P.; Pierce, David A.

    2013-11-01

    Three different solution-based approaches were taken to make sodalite minerals as a host for a mixed salt simulating the waste in the electrochemical separations process of nuclear fuel reprocessing. The methods used an aqueous solution of mixed chlorides (simulated waste) but the other reactants varied: (1) Al(OH)3 + NaOH + CS, (2) NaAlO2 + CS, and (3) Al2Si2O7 + NaOH, (CS = colloidal silica). The products were dried, ground, pressed into pellets, and fired at 650-950 °C. In some cases, either 5 or 10 mass% of a Si-Na-B oxide glass sintering aid was introduced at different stages in the process. Method (2) proved the most successful at producing high sodalite fractions (up to 100%) with minimal sintering aid additions and showed high consolidation potential (up to 91.4% of theoretical density) at reduced firing temperatures.

  10. Ice VII from aqueous salt solutions: From a glass to a crystal with broken H-bonds

    PubMed Central

    Klotz, S.; Komatsu, K.; Pietrucci, F.; Kagi, H.; Ludl, A.-A.; Machida, S.; Hattori, T.; Sano-Furukawa, A.; Bove, L. E.

    2016-01-01

    It has been known for decades that certain aqueous salt solutions of LiCl and LiBr readily form glasses when cooled to below ≈160 K. This fact has recently been exploited to produce a « salty » high-pressure ice form: When the glass is compressed at low temperatures to pressures higher than 4 GPa and subsequently warmed, it crystallizes into ice VII with the ionic species trapped inside the ice lattice. Here we report the extreme limit of salt incorporation into ice VII, using high pressure neutron diffraction and molecular dynamics simulations. We show that high-pressure crystallisation of aqueous solutions of LiCl∙RH2O and LiBr∙RH2O with R = 5.6 leads to solids with strongly expanded volume, a destruction of the hydrogen-bond network with an isotropic distribution of water-dipole moments, as well as a crystal-to-amorphous transition on decompression. This highly unusual behaviour constitutes an interesting pathway from a glass to a crystal where translational periodicity is restored but the rotational degrees of freedom remaining completely random. PMID:27562476

  11. Ice VII from aqueous salt solutions: From a glass to a crystal with broken H-bonds.

    PubMed

    Klotz, S; Komatsu, K; Pietrucci, F; Kagi, H; Ludl, A-A; Machida, S; Hattori, T; Sano-Furukawa, A; Bove, L E

    2016-08-26

    It has been known for decades that certain aqueous salt solutions of LiCl and LiBr readily form glasses when cooled to below ≈160 K. This fact has recently been exploited to produce a « salty » high-pressure ice form: When the glass is compressed at low temperatures to pressures higher than 4 GPa and subsequently warmed, it crystallizes into ice VII with the ionic species trapped inside the ice lattice. Here we report the extreme limit of salt incorporation into ice VII, using high pressure neutron diffraction and molecular dynamics simulations. We show that high-pressure crystallisation of aqueous solutions of LiCl∙RH2O and LiBr∙RH2O with R = 5.6 leads to solids with strongly expanded volume, a destruction of the hydrogen-bond network with an isotropic distribution of water-dipole moments, as well as a crystal-to-amorphous transition on decompression. This highly unusual behaviour constitutes an interesting pathway from a glass to a crystal where translational periodicity is restored but the rotational degrees of freedom remaining completely random.

  12. Administration of balanced or BCAA-enriched amino acid solution in septic rats. Effects on protein synthesis in the liver.

    PubMed Central

    Pedersen, P; Li, S J; Hasselgren, P O; LaFrance, R; Fischer, J E

    1988-01-01

    Total hepatic protein synthesis was measured in vivo with a flooding-dose technique, and the production of total secreted proteins, albumin, complement component C3, and seromucoid fraction was measured in perfused livers of septic rats that received one of three different solutions infused intravenously; Group 1 received 16.4% dextrose; Group 2 received Aminosyn (25% BCAA) in 10.6% dextrose, and Group 3 received Freamine HBC (45% BCAA) in 10.6% dextrose. All solutions were isocaloric, and the amino acid solutions were isonitrogenous. The solutions were administered for 18 or 48 hours after the induction of sepsis. There were no significant differences in mortality rates in the three treatment groups. The negative nitrogen balance seen in the dextrose-infused animals was reversed to the same degree by the two different amino acid solutions. There were no significant differences in hepatic protein synthesis rates in vivo between the three groups of rats. Synthesis rates of secreted proteins in perfused liver were similar in the different treatment groups in the 18-hour experiments, whereas in the 48-hour experiments, synthesis rates of total secreted proteins, C3, and the serumucoid fraction were higher in Group 1 than in Groups 2 and 3. The results suggest that administration of an amino acid solution improves nitrogen balance in sepsis, but that this effect is not caused by stimulated hepatic protein synthesis. The nitrogen-sparing effect during sepsis of a branched chain amino acid (BCAA)-enriched solution does not seem to be superior to that of a balanced amino acid solution. PMID:3143320

  13. Salt water interface in a layered coastal aquifer: The only published analytic solution is in error

    NASA Astrophysics Data System (ADS)

    Strack, O. D. L.

    2016-02-01

    We consider the approach applied by Rumer and Shiau (1968) to interface flow in a layered coastal aquifer. The authors match the boundary conditions along the interfaces between layers of different hydraulic conductivities by changing the vertical scale of the layers, which causes violation of the governing equations. In particular, the mass balance equation is not met in each of the transformed layers.

  14. Salting-out in the aqueous single-protein solution: the effect of shape factor.

    PubMed

    Chang, Bong Ho; Bae, Young Chan

    2003-06-01

    A molecular-thermodynamic model is developed to describe salt-induced protein precipitation. The protein-protein interaction goes through the potential of mean force. An equation of state is derived based on the generalized van der Waals partition function. The attractive term including the potential of mean force is perturbed by the statistical mechanical perturbation theory. The precipitation behaviors are studied by calculating the partition coefficient with various conditions such as the ionic strength and the shape of protein. Our results show that the protein shape plays a significant role in the protein precipitation behavior.

  15. IUPAC-NIST Solubility Data Series. 104. Lithium Sulfate and its Double Salts in Aqueous Solutions

    NASA Astrophysics Data System (ADS)

    Sohr, Julia; Voigt, Wolfgang; Zeng, Dewen

    2017-06-01

    The solubility data for lithium sulfate and its double salts in water are reviewed. Where appropriate, binary, ternary, and multicomponent systems are critically evaluated. The best values were selected on basis of these evaluations and presented in tabular form. Fitting equations and plots are provided. The quantities, units, and symbols used are in accord with IUPAC recommendations. The original data have been reported and, if necessary, transferred into the units and symbols recommended by IUPAC. The literature on solubility data is covered up to the end of 2015.

  16. Nutrient and salt mass balance on the Lower Arkansas River and a contributing tributary in an irrigated agricultural setting

    Treesearch

    Alexander Hulzenga; Ryan T. Bailey; Timothy K. Gates

    2016-01-01

    The Lower Arkansas River Basin is an irrigated, agricultural valley suffering from high concentrations of nutrients and salts in the coupled groundwater-surface water system. The majority of water quality data collection and associated spatial analysis of concentrations and mass loadings from the aquifer to the stream network has been performed at the regional scale (...

  17. Effects of salt concentrations of the aqueous peptide-amphiphile solutions on the sol-gel transitions, the gelation speed, and the gel characteristics.

    PubMed

    Otsuka, Takahiro; Maeda, Tomoki; Hotta, Atsushi

    2014-10-02

    Hydrogels made of peptide amphiphiles (PA) have attracted a lot of interest in biomedical fields. Considering the applications of PA hydrogels, the control of the gelation speed and the gel characteristics is essential to predominantly determine the usefulness and practicability of the hydrogels. In this work, the effects of the salt concentrations using sodium dihydrogenorthophosphate (NaH2PO4) on the sol-gel transition behaviors, especially the gelation speed and the gel characteristics of the designed PA (C16-W3K) hydrogels in aqueous solution were discussed. It was found that the original solution state before rheological testing was independent of the salt concentration, which was confirmed by observing the self-assembly structures and the peptide secondary structures of PA through transmission electron microscopy (TEM) and circular dichroism spectroscopy (CD). The PA solutions with different salt concentrations, however, presented a profound difference in the gelation speed and the gel characteristics: the solution exhibited higher gelation speeds and higher mechanical properties at higher salt concentrations. Concurrently, the density, the length of wormlike micelles, and the conformational ratio of β-sheets to α-helices in the equilibrium PA solutions all increased with the increase in the salt concentrations.

  18. Solubilities and Glass Formation in Aqueous Solutions of the Sodium Salts of Malonic Acid With and Without Ammonium Sulfate.

    PubMed

    Kissinger, Jared A; Buttke, Lukas G; Vinokur, Anastasiya I; Guzei, Ilia A; Beyer, Keith D

    2016-06-02

    The solubility of sodium hydrogen malonate and sodium malonate in water both with and without ammonium sulfate present has been studied using differential scanning calorimetry and infrared spectroscopy. The crystals that form from sodium hydrogen malonate/water solutions were determined to be sodium hydrogen malonate monohydrate by single-crystal X-ray diffractometry. The crystals formed in sodium malonate/water solutions were determined to be sodium malonate monohydrate, a compound whose structure had not been previously known. When ammonium sulfate is added to these respective aqueous systems, the precipitation solids contain sodium sulfate decahydrate under low to moderate ammonium concentrations and lecontite (NaNH4SO4·2H2O) under high ammonium concentrations, which can be found under dry atmospheric conditions. Thus, it appears the presence of malonate and hydrogen malonate ions does not significantly affect the precipitation of inorganic salts in these systems. The glass transition temperatures of all solutions were also determined, and it was observed that the addition of ammonium sulfate slightly lowers the glass transition temperature in these solutions.

  19. Molten-salt synthesis and composition-dependent luminescent properties of barium tungsto-molybdate-based solid solution phosphors

    NASA Astrophysics Data System (ADS)

    Xiang-Hong, He; Zhao-Lian, Ye; Ming-Yun, Guan; Ning, Lian; Jian-Hua, Sun

    2016-02-01

    Pr3+-activated barium tungsto-molybdate solid solution phosphor Ba(Mo1-zWz)O4:Pr3+ is successfully fabricated via a facile molten-salt approach. The as-synthesized microcrystal is of truncated octahedron and exhibits deep-red-emitting upon blue light excitation. Powder x-ray diffraction and Raman spectroscopy techniques are utilized to investigate the formation of solid solution phosphor. The luminescence behaviors depend on the resulting composition of the microcrystals with fixed Pr3+-doping concentration, while the host lattices remain in a scheelite structure. The forming solid solution via the substitution of [WO4] for [MoO4] can significantly enhance its luminescence, which may be due to the fact that Ba(Mo1-zWz)O4:Pr3+ owns well-defined facets and uniform morphologies. Owing to its properties of high phase purity, well-defined facets, highly uniform morphologies, exceptional chemical and thermal stabilities, and stronger emission intensity, the resulting solid solution phosphor is expected to find potential applications in phosphor-converted white light-emitting diodes (LEDs). Project supported by the Construction Fund for Science and Technology Innovation Group from Jiangsu University of Technology, China, the Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, China (Grant No. KHK1409), the Priority Academic Program Development of Jiangsu Higher Education Institutions, China, and the National Natural Science Foundation of China (Grant No. 21373103).

  20. Small-angle neutron scattering study of structure and interaction during salt-induced liquid-liquid phase transition in protein solutions

    NASA Astrophysics Data System (ADS)

    Chinchalikar, A. J.; Aswal, V. K.; Kohlbrecher, J.; Wagh, A. G.

    2013-06-01

    The liquid-liquid phase transition (LLPT) in aqueous salt solutions of lysozyme protein has been studied by small-angle neutron scattering. Measurements have been carried out on fixed protein concentration with varying salt concentration approaching LLPT. The data are fitted considering protein interaction by the two Yukawa (2Y) potential which combines short-range attraction and long-range repulsion. We show that LLPT arises because of enhancement of non-DLVO (Derjaguin-Landau-Verwey-Overbeek) short-range attraction without any conformational structural change of the protein. The salt concentration required for LLPT as well as corresponding short-range attraction decreases significantly with increase in protein concentration.

  1. Direct Experimental Evidence for Halogen-Aryl π Interactions in Solution from Molecular Torsion Balances.

    PubMed

    Sun, Han; Horatscheck, André; Martos, Vera; Bartetzko, Max; Uhrig, Ulrike; Lentz, Dieter; Schmieder, Peter; Nazaré, Marc

    2017-06-01

    We dissected halogen-aryl π interactions experimentally using a bicyclic N-arylimide based molecular torsion balances system, which is based on the influence of the non-bonded interaction on the equilibria between folded and unfolded states. Through comparison of balances modulated by higher halogens with fluorine balances, we determined the magnitude of the halogen-aryl π interactions in our unimolecular systems to be larger than -5.0 kJ mol(-1) , which is comparable with the magnitude estimated in the biomolecular systems. Our study provides direct experimental evidence of halogen-aryl π interactions in solution, which until now have only been revealed in the solid state and evaluated theoretically by quantum-mechanical calculations. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Fracture phenomena in an isotonic salt solution during freezing and their elimination using glycerol.

    PubMed

    Gao, D Y; Lin, S; Watson, P F; Critser, J K

    1995-06-01

    Thermal stress and consequent fracture in frozen organs or cell suspensions have been proposed to be two causes of cell cryoinjury. A specific device was developed to study the thermal stress and the fracture phenomena during a slow cooling process of isotonic NaCl solutions with different concentrations of glycerol (cryoprotectant) in a cylindrical tube. It was shown from the experimental results that glycerol significantly influenced the solidification process of the ternary solutions and reduced the thermal stress. The higher the initial glycerol concentration, the lower the thermal stress in the frozen solutions. Glycerol concentrations over 0.3 M were sufficient to eliminate the fracture of the frozen solutions under the present experimental conditions. To explain the action of glycerol in reducing the thermal stress and preventing the ice fracture, a further study on ice crystal formation and growth of ice in these solutions was undertaken using cryomicroscopy. It is known from previous studies that an increase of initial glycerol concentration reduced frozen fraction of water in the solution at any given low temperature due to colligative properties of solution, which reduced the total ice volume expansion during water solidification. The present cryomicroscopic investigation showed that under a fixed cooling condition the different initial glycerol concentrations induced the different microstructures of the frozen solutions at not only a given low temperature but also a given frozen fraction of water. It has been known that ice volume expansion during solidification is a major factor causing the thermal stress and the interior microstructure is critical for the mechanical strength of a solid. Therefore, functions of glycerol in reducing the total ice volume expansion during water solidification and in influencing interior microstructure of the ice may contribute to reduce the thermal stress and prevent the fracture in the frozen solutions.

  3. Conformation dynamics and polarization effect of α,α-trehalose in a vacuum and in aqueous and salt solutions.

    PubMed

    Kan, Zigui; Yan, Xiufen; Ma, Jing

    2015-03-05

    Conformational changes of α,α-trehalose in a vacuum, water, and 0-20 wt % NaCl solutions were investigated by means of molecular dynamics (MD) simulations at different levels of density function theory (DFT) and with fixed-charge nonpolarizable and variable-charge force fields (FFs), respectively. The relative thermodynamic stability of trehalose is enhanced by the formation of intercycle and/or intracycle hydrogen bonds, but some thermodynamically unfavorable structures can be sampled in the DFT-based ab initio MD simulation. The polarization effects of polar trehalose molecule in aqueous and NaCl solutions were studied by a series of MD simulations with both the conventional nonpolarizable and polarizable force field models. In the polarizable model, the partial charges of trehalose were updated every 2 ps using DFT calculations and fused with the other FF parameters for the energy calculation and MD simulation. Around the trehalose, water molecules located in an asymmetry model and trehalose have a stronger tendency to bind with water molecules than Na(+) and Cl(-) ions. When the trehalose concentration is increased from 3.26 to 6.31 wt % in salt aqueous solution, the two trehalose molecules periodically approach each other in a nearly anhydrate state and leave a way to keep the favorable hydration structure with the mean trehalose-trehalose distance of 8.6 Å. The similarity between the solvated dimer packing styles (shoulder-by-shoulder or head-to-head) and crystal stacking can be used to make an extrapolation to higher sugar concentrations and to rationalize the bioprotection function of trehalose in high salt concentration.

  4. Effects of high calcium diet on arterial smooth muscle function and electrolyte balance in mineralocorticoid-salt hypertensive rats.

    PubMed Central

    Arvola, P.; Ruskoaho, H.; Pörsti, I.

    1993-01-01

    1. The effects of a high calcium diet (2.5%) on blood pressure, electrolyte balance, plasma and tissue atrial natriuretic peptide (ANP), cytosolic free Ca2+ concentration ([Ca2+]i), and arterial smooth muscle responses were studied in one-kidney deoxycorticosterone (DOC)-NaCl hypertensive Wistar rats. 2. Calcium supplementation for 8 weeks markedly attenuated the development of DOC-NaCl hypertension and the associated cardiac hypertrophy, and prevented the DOC-NaCl-induced sodium-volume retention as judged by reduced plasma Na+, and decreased plasma and ventricular ANP concentrations in high calcium-fed DOC-NaCl rats. However, calcium supplementation did not affect the DOC-NaCl-induced rise in platelet [Ca2+]i. 3. Smooth muscle contractions of isolated mesenteric arterial rings in response to depolarization by K+ (20-30 mM) were enhanced in DOC-NaCl-treated rats, this enhancement being abolished by concurrent oral calcium loading. The Ca2+ entry blocker nifedipine (10 nM) inhibited the contractions induced by K+ (30-125 mM) more effectively in DOC-NaCl rats than in controls, while the inhibition in calcium-loaded DOC-NaCl rats was significantly greater than in controls only with 30 mM K+. 4. The contractions of mesenteric arterial rings induced by omission of K+ from the organ baths were used to evaluate cell membrane permeability to ions. In chemically denervated rings the onset of the gradual rise in contractile force in K(+)-free medium occurred earlier, and the rate of the contraction was faster in DOC-NaCl-treated rats than in controls and high calcium-fed DOC-NaCl rats. Smooth muscle relaxation induced by 0.5 mM K+ upon K(+)-free contractions was clearly slower in DOC-NaCl rats than in controls and calcium-supplemented DOC-NaCl rats. 5. The functions of arterial smooth muscle Na+, Ca2+ exchange and Ca(2+)-ATPase were evaluated by the aortic contractions elicited by low Na+ medium, and the subsequent relaxation responses induced by Ca(2+)-free solution (in the

  5. On the hydrophilicity of polyzwitterion poly (N,N-dimethyl-N-(3-(methacrylamido)propyl)ammoniopropane sulfonate) in water, deuterated water, and aqueous salt solutions.

    PubMed

    Hildebrand, Viet; Laschewsky, André; Zehm, Daniel

    2014-01-01

    A series of zwitterionic model polymers with defined molar masses up to 150,000 Da and defined end groups are prepared from sulfobetaine monomer N,N-dimethyl-N-(3-(methacrylamido)propyl)ammoniopropanesulfonate (SPP). Polymers are synthesized by reversible addition-fragmentation chain transfer polymerization (RAFT) using a functional chain transfer agent labeled with a fluorescent probe. Their upper critical solution temperature-type coil-to-globule phase transition in water, deuterated water, and various salt solutions is studied by turbidimetry. Cloud points increase with polyzwitterion concentration and molar mass, being considerably higher in D2O than in H2O. Moreover, cloud points are strongly affected by the amount and nature of added salts. Typically, they increase with increasing salt concentration up to a maximum value, whereas further addition of salt lowers the cloud points again, mostly down to below freezing point. The different salting-in and salting-out effects of the studied anions can be correlated with the Hofmeister series. In physiological sodium chloride solution and in phosphate buffered saline (PBS), the cloud point is suppressed even for high molar mass samples. Accordingly, SPP-polymers behave strongly hydrophilic under most conditions encountered in biomedical applications. However, the direct transfer of results from model studies in D2O, using, e.g. (1)H NMR or neutron scattering techniques, to 'normal' systems in H2O is not obvious.

  6. Extraction of cerium-group lanthanide (III) nitrates from concentrated aqueous salt solutions by tributyl phosphate

    SciTech Connect

    Pyartman, A.K.; Kopyrin, A.A.; Puzikov, E.A.

    1995-01-01

    The extraction equilibrium for a hypothetical standard, designated as 1 M aqueous solution of Ln(III) nitrate and the state of the pure components in organic phase with a mole fraction of 1 have been determined assuming formation of tri- and tetrasolvates of the metal(III) nitrates in organic phase. The excessive thermodynamic functions of mixing tri-n-butyl phosphate with solutions of Ln(III) nitrate trisolvates are presented.

  7. Performance evaluation of ant colony optimization-based solution strategies on the mixed-model assembly line balancing problem

    NASA Astrophysics Data System (ADS)

    Akpinar, Sener; Mirac Bayhan, G.

    2014-06-01

    The aim of this article is to compare the performances of iterative ant colony optimization (ACO)-based solution strategies on a mixed-model assembly line balancing problem of type II (MMALBP-II) by addressing some particular features of real-world assembly line balancing problems such as parallel workstations and zoning constraints. To solve the problem, where the objective is to minimize the cycle time (i.e. maximize the production rate) for a predefined number of workstations in an existing assembly line, two ACO-based approaches which differ in the mission assigned to artificial ants are used. Furthermore, each ACO-based approach is conducted with two different pheromone release strategies: global and local pheromone updating rules. The four ACO-based approaches are used for solving 20 representative MMALBP-II to compare their performance in terms of computational time and solution quality. Detailed comparison results are presented.

  8. [Study on the spectra of NTO and its rubidium salt in aqueous solution].

    PubMed

    Xia, Shu-Ping; Hu, Man-Cheng; Gao, Shi-Yang; Jiang, Yu-Cheng

    2005-05-01

    In this paper, the Raman and difference FTIR spectra of NTO crystal, NTO solutions at different pH and saturated aqueous solution of Rb(NTO) x H2O have been studied. The determined structure of crystal suggests that the metal ion with oxygen and nitrogen atoms of [chemical structure see text] C-N, [chemical structure see text] C-NO2, [chemical structure see text] C=O and H2O formed bonds. The highest characterization peaks of Raman and FTIR spectra show that [chemical structure see text] C-NO2, [chemical structure see text] C=O and [chemical structure see text] C-N of NTO- formed week coordination bonds. The vibration spectra of saturation solution basically accord with those of the crystal. The bonds of saturation solution of the coordination compound have not changed. Therefore, the different vibration spectra of the saturation water solution of Rb (NTO) x H2O can be explicated by the formation of the bonds in crystal. The coordination compound formation mechanism of metal ion with NTO in alkali aqueous solution is discussed.

  9. Use of alkali metal salts to prepare high purity single-walled carbon nanotube solutions and thin films

    NASA Astrophysics Data System (ADS)

    Ashour, Rakan F.

    Single-walled carbon nanotubes (SWCNTs) display interesting electronic and optical properties desired for many advanced thin film applications, such as transparent conductive electrodes or thin-film transistors. Large-scale production of SWCNTs generally results in polydispersed mixtures of nanotube structures. Since SWCNT electronic character (conducting or semiconducting nature) depends on the nanotube structure, application performance is being held back by this inability to discretely control SWCNT synthesis. Although a number of post-production techniques are able to separate SWCNTs based on electronic character, diameter, or chirality, most still suffer from the disadvantage of high costs of materials, equipment, or labor intensity to be relevant for large-scale production. On the other hand, chromatographic separation has emerged as a method that is compatible with large scale separation of metallic and semiconducting SWCNTs. In this work, SWCNTs, in an aqueous surfactant suspension of sodium dodecyl sulfate (SDS), are separated by their electronic character using a gel chromatography process. Metallic SWCNTs (m-SWCNTs) are collected as initial fractions since they show minimum interaction with the gel medium, whereas, semiconducting SWCNTs (sc- SWCNTs) remain adsorbed to the gel. The process of sc-SWCNT retention in the gel is found to be driven by the packing density of SDS around the SWCNTs. Through a series of separation experiments, it is shown that sc-SWCNTs can be eluted from the gel simply by disturbing the configuration of the SDS/SWCNT micellar structure. This is achieved by either introducing a solution containing a co-surfactant, such as sodium cholate (SC), or solutions of alkali metal ionic salts. Analysis of SWCNT suspensions by optical absorption provides insights into the effect of changing the metal ion (M+ = Li+, Na+, and K+) in the eluting solution. Salts with smaller metal ions (e.g. Li+) require higher concentrations to achieve

  10. Generalized chloride mass balance: Forward and inverse solutions for one-dimensional tracer convection under transient flux

    SciTech Connect

    Ginn, T.R.; Murphy, E.M.

    1996-12-01

    Forward and inverse solutions are provided for analysis of inert tracer profiles resulting from one-dimensional convective transport under fluxes which vary with time and space separately. The developments are displayed as an extension of conventional chloride mass balance (CMB) techniques to account for transient as well as space-dependent water fluxes. The conventional chloride mass balance has been used over two decades to estimate recharge over large time scales in arid environments. In this mass balance approach, the chloride concentration in the pore water, originating from atmospheric fallout, is inversely proportional to the flux of water through the sediments. The CMB method is especially applicable to arid and semi-arid regions where evapotranspirative enrichment of the pore water produces a distinct chloride profile in the unsaturated zone. The solutions presented allow incorporation of transient fluxes and boundary conditions in CMB analysis, and allow analysis of tracer profile data which is not constant with depth below extraction zone in terms of a rational water transport model. A closed-form inverse solution is derived which shows uniqueness of model parameter and boundary condition (including paleoprecipitation) estimation, for the specified flow model. Recent expressions of the conventional chloride mass balance technique are derived from the general model presented here; the conventional CMB is shown to be fully compatible with this transient flow model and it requires the steady-state assumption on chloride mass deposition only (and not on water fluxes or boundary conditions). The solutions and results are demonstrated on chloride profile data from west central New Mexico.

  11. The effect of solution electrolytes on the uptake of photosensitizers by liposomal membranes: a salting-out effect.

    PubMed

    Minnes, Refael; Ytzhak, Shany; Weitman, Hana; Ehrenberg, Benjamin

    2008-09-01

    In this study we investigated, spectroscopically, the effect of electrolytes on the partitioning of hematoporphyrin IX (HP) and hypericin (Hy) into non-charged lipid vesicles. Our aim was to assess the salting-out effect of electrolytes on membrane-partitioning. We titrated aqueous solutions of HP and Hy with lecithin liposomes, at different concentrations of several monovalent and divalent electrolytes in the suspension. The partitioning constant of HP to lecithin liposomes increased from 3.3 (mL/mg) in water containing only 5mM buffer to 8.7 (mL/mg) at 0.36M KCl. KF had a similar effect. NaCl caused a 3-fold increase in the partitioning of Hy to liposomes. MgSO(4) and MgCl(2) also increased the partitioning of HP, by a factor of more than 4 and this occurred already at 0.03M concentration. We analyze the comparative effects of the electrolytes in relation to the Hofmeister series. The salting-out effect could be utilized to enhance the uptake of HP and Hy, and possibly other photosensitizers as well, by artificial and natural membranes.

  12. Parallel patterning of SiO2 wafer via near-field electrospinning of metallic salts and polymeric solution mixtures

    NASA Astrophysics Data System (ADS)

    Hu, Sanyuan; Li, Heping; Su, Zhen; Yan, Youwei

    2017-10-01

    This paper describes a near-field electrospinning technique combined with heat treatment process used to directly align parallel metal oxide and metal nitride fibers on silicon dioxide substrate. The effects of near-field electrospinning parameters (including collector-to-needle distance, applied voltage and the moving speed of the collector) on the morphology of the resulted fibers have been studied. Metallic salt-contained precursor fibers are individually aligned via near-field electrospinning of metallic salts and polymeric solution mixtures. After applying calcination process to these well aligned precursor fibers, patterning by metal oxide and metal nitride fibers such as ZnO, Ga2O3, TiO2, GaN and TiN is successfully obtained. The optical microscope images and the scanning electron microscopy show the presence of fiber patterns, whose crystalline structure is characterized by x-ray diffraction and Raman spectroscopy measurement. The results demonstrate the potential of this approach for assembling ceramic fibers into parallel arrays with controllable orientation and position.

  13. Results of Hg speciation testing on MCU strip effluent hold tank (SEHT) and decontaminated salt solution hold tank (DSSHT) materials

    SciTech Connect

    Bannochie, C. J.

    2015-09-17

    The Savannah River National Laboratory (SRNL) was tasked with preparing and shipping samples for Hg speciation by Eurofins Frontier Global Sciences, Inc. in Seattle, WA on behalf of the Savannah River Remediation (SRR) Mercury Task Team.i,ii The tenth shipment of samples was designated to include Modular Caustic Side Solvent Extraction Unit (MCU) Strip Effluent Hold Tank (SEHT) and MCU Decontaminated Salt Solution Hold Tank (DSSHT) materials from processing Salt Batch 7b. The MCU SEHT (MCU-15-722) and DSSHT (MCU-15-709) samples were pulled on June 15, 2015. All MCU samples were received at SRNL on June 16, 2015. The DSSHT sample was moved the same day to refrigeration, while the SEHT sample was placed in the Shielded Cells. On July 9, 2015 it was opened and an aliquot diluted 1:100 with Eurofins deionized water and a portion of the diluted sample transferred to a Teflon® bottle prior to moving it to refrigeration that same day. All samples were kept in the dark and refrigerated until final dilutions were prepared for shipment to Eurofins.

  14. A molecular dynamic study on the dissociation mechanism of SI methane hydrate in inorganic salt aqueous solutions.

    PubMed

    Xu, Jiafang; Chen, Zhe; Liu, Jinxiang; Sun, Zening; Wang, Xiaopu; Zhang, Jun

    2017-08-01

    Gas hydrate is not only a potential energy resource, but also almost the biggest challenge in oil/gas flow assurance. Inorganic salts such as NaCl, KCl and CaCl2 are widely used as the thermodynamic inhibitor to reduce the risk caused by hydrate formation. However, the inhibition mechanism is still unclear. Therefore, molecular dynamic (MD) simulation was performed to study the dissociation of structure I (SI) methane hydrate in existence of inorganic salt aqueous solution on a micro-scale. The simulation results showed that, the dissociation became stagnant due to the presence of liquid film formed by the decomposed water molecules, and more inorganic ions could shorten the stagnation-time. The diffusion coefficients of ions and water molecules were the largest in KCl system. The structures of ion/H2O and H2O/H2O were the most compact in hydrate/NaCl system. The ionic ability to decompose hydrate cells followed the sequence of: Ca(2+)>2K(+)>2Cl(-)>2Na(+). Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Stabilizing Superionic-Conducting Structures via Mixed-Anion Solid Solutions of Monocarba- closo -borate Salts

    SciTech Connect

    Tang, Wan Si; Yoshida, Koji; Soloninin, Alexei V.; Skoryunov, Roman V.; Babanova, Olga A.; Skripov, Alexander V.; Dimitrievska, Mirjana; Stavila, Vitalie; Orimo, Shin-ichi; Udovic, Terrence J.

    2016-10-14

    Solid lithium and sodium closo-polyborate-based salts are capable of superionic conductivities surpassing even liquid electrolytes, but often only at above-ambient temperatures where their entropically driven disordered phases become stabilized. Here we show by X-ray diffraction, quasielastic neutron scattering, differential scanning calorimetry, NMR, and AC impedance measurements that by introducing 'geometric frustration' via the mixing of two different closo-polyborate anions, namely, 1-CB9H10- and CB11H12-, to form solid-solution anion-alloy salts of lithium or sodium, we can successfully suppress the formation of possible ordered phases in favor of disordered, fast-ion-conducting alloy phases over a broad temperature range from subambient to high temperatures. This result exemplifies an important advancement for further improving on the remarkable conductive properties generally displayed by this class of materials and represents a practical strategy for creating tailored, ambient-temperature, solid, superionic conductors for a variety of upcoming all-solid-state energy devices of the future.

  16. Parallel patterning of SiO2 wafer via near-field electrospinning of metallic salts and polymeric solution mixtures.

    PubMed

    Hu, Sanyuan; Li, Heping; Su, Zhen; Yan, Youwei

    2017-08-08

    This paper describes a near-field electrospinning technique combined with heat treatment process used to directly align parallel metal oxide and metal nitride fibers on silicon dioxide substrate. The effects of near-field electrospinning parameters (including collector-to-needle distance, applied voltage and the moving speed of the collector) on the morphology of the resulted fibers have been studied. Metallic salt-contained precursor fibers are individually aligned via near-field electrospinning of metallic salts and polymeric solution mixtures. After applying calcination process to these well aligned precursor fibers, patterning by metal oxide and metal nitride fibers such as ZnO, Ga2O3, TiO2, GaN and TiN is successfully obtained. The optical microscope images and the scanning electron microscopy show the presence of fiber patterns, whose crystalline structure is characterized by X-ray diffraction and Raman spectroscopy measurement. The results demonstrate the potential of this approach for assembling ceramic fibers into parallel arrays with controllable orientation and position. © 2017 IOP Publishing Ltd.

  17. Effect of laser irradiation of nanoparticles in aqueous uranium salt solutions on nuclide activity

    SciTech Connect

    Simakin, Aleksandr V; Shafeev, Georgii A

    2011-07-31

    This paper presents an experimental study of the effect of laser irradiation of aqueous uranyl chloride solutions containing gold nanoparticles on the activity of the uranium series radionuclides {sup 234}Th, {sup 234m}Pa, and {sup 235}U. The solutions were exposed to femtosecond Ti:sapphire laser pulses and to the second or third harmonic of a Nd:YAG laser (150-ps pulses) at a peak intensity in the medium of {approx}10{sup 12} W cm{sup -2}. The activities of the radionuclides in the irradiated solutions were shown to differ markedly from their equilibrium values. The sign of the deviation depends on the laser wavelength. The measured activity deviations can be interpreted as evidence that laser exposure of nanoparticles accelerates the alpha and beta decays of the radionuclides. The observed effects are accounted for in terms of a mechanism that involves resonant enhancement of optical waves by metallic nanoparticles. (interaction of laser radiation with matter)

  18. Numerical simulation of solidification in a horizontal cylindrical annulus charged with an aqueous salt solution

    NASA Technical Reports Server (NTRS)

    Neilson, D. G.; Incropera, F. D.; Bennon, W. D.

    1990-01-01

    A computational study of solidification of a binary Na2CO3 solution in a horizontal cylindrical annulus is performed using a continuum formulation with a control-volume based, finite-difference scheme. The initial conditions were selected to facilitate the study of counter thermal and solutal convection, accompanied by extensive mushy region growth. Numerical results are compared with experimental data with mixed success. Qualitative agreement is obtained for the overall solidification process and associated physical phenomena. However, the plume thickness calculated for the solutally-driven convective upflow is substantially smaller than the observed value. Evolution of double-diffusive layers is predicted, but over a time scale much smaller than that observed experimentally. Good agreement is obtained between predicted and measured results for solid growth, but the mushy region thickness is significantly overpredicted.

  19. Experimental study of evaporation of horizontal films of water-salt solutions

    NASA Astrophysics Data System (ADS)

    Elistratov, S. L.; Morozov, V. S.

    2015-01-01

    The present studies were carried out for the horizontal films (thin layers) of water and water solutions of NaCl, CaCl2, LiCl, and LiBr with different solubility characteristics, as well as with specific features of formation and decay of water hydrates. Required volume of solution Vo of given weight concentration ξo, preliminary heated to the working surface temperature, was put in one step on the horizontal bottom of the bowl, heated to working temperature tCT, by means of volume batchers Thermo Scientific. After evaporation completion, the final mass of solution and form of their residue were registered. At the final stage of evaporation formation of NaCl crystals and water hydrates of CaCl2 · 2H2O, LiCl · H2O, and LiBr · 2H2O occurred.

  20. Effect of salt identity on the phase diagram for a globularprotein in aqueous electrolyte solution

    SciTech Connect

    Bostrom, Mathias; Tavares, Frederico W.; Ninham, Barry W.; Prausnitz, John M.

    2006-02-22

    Monte Carlo simulations are used to establish the potential of mean force between two globular proteins in an aqueous electrolyte solution. This potential includes nonelectrostatic contributions arising from dispersion forces first, between the globular proteins, and second, between ions in solution and between each ion and the globular protein. These latter contributions are missing from standard models. The potential of mean force, obtained from simulation, is fitted to an analytic equation. Using our analytic potential of mean force and Barker-Henderson perturbation theory, we obtain phase diagrams for lysozyme solutions that include stable and metastable fluid-fluid and solid-fluid phases when the electrolyte is 0.2 M NaSCN or NaI or NaCl. The nature of the electrolyte has a significant effect on the phase diagram.

  1. Water purification using organic salts

    DOEpatents

    Currier, Robert P.

    2004-11-23

    Water purification using organic salts. Feed water is mixed with at least one organic salt at a temperature sufficiently low to form organic salt hydrate crystals and brine. The crystals are separated from the brine, rinsed, and melted to form an aqueous solution of organic salt. Some of the water is removed from the aqueous organic salt solution. The purified water is collected, and the remaining more concentrated aqueous organic salt solution is reused.

  2. Effect of salt solutions applied during wheat conditioning on lipase activity and lipid stability of whole wheat flour.

    PubMed

    Doblado-Maldonado, Andrés F; Arndt, Elizabeth A; Rose, Devin J

    2013-09-01

    Lipolytic activity in whole wheat flour (WWF) is largely responsible for the loss in baking quality during storage. Metal ions affect the activity of seed lipases; however, no previous studies have applied this information to WWF in a way that reduces lipase activity, is practical for commercial manufacture, and uses common food ingredients. NaCl, KCl, Ca-propionate, or FeNa-ethylenediaminetetraacetic acid (FeNa-EDTA) were applied to hard red winter (HRW) and hard white spring (HWS) wheats during conditioning as aqueous solutions at concentrations that would be acceptable in baked goods. Salts affected lipase activity to different degrees depending on the type of wheat used. Inhibition was greater in HRW compared with HWS WWF, probably due to higher lipase activity in HRW wheat. In HRW WWF, 1% NaCl (flour weight) reduced hydrolytic and oxidative rancidity and resulted in higher loaf volume and lower firmness than untreated WWF after 24 weeks of storage.

  3. Rich aggregate morphologies induced by organic salts in aqueous solutions of a cationic gemini surfactant with a short spacer.

    PubMed

    Jiang, Rong; Zhao, Jianxi; Hu, Xiaoming; Pei, Xiaomei; Zhang, Lixiang

    2009-12-01

    Various aggregates, such as spherical and elongated micelles, tubular and rodlike aggregates, as well as vesicles, are induced by adding sodium 2-naphthalenesulfonate (SNphs) or sodium benzenesulfonate (SBzs) into the aqueous solution of a gemini surfactant C12C2C12(Me) (1,2-ethanediyl-bis-(dodecyldimethylammonium bromide)). The aggregate morphology strongly depends on the added amount of the organic salts. Among the various aggregates, the elongated micelle and the tubular aggregate have larger solubilizing capacities than those with the other morphologies. However, SNphs and SBzs cannot induce similar aggregate transitions for the systems of C12CsC12(Me) (s=6, 8, 12). The possible mechanism of these phenomena is proposed based on the results of UV spectra and 1H NMR measurements and the molecular packing geometry rule.

  4. Analysis of the corrosion of carbon steels in simulated salt repository brines and acid chloride solutions at high temperatures

    SciTech Connect

    Diercks, D.R.; Kassner, T.F.

    1988-04-01

    An analysis of literature data on the corrosion of carbon steels in anoxic brines and acid chloride solutions was performed, and the results were used to assess the expected life of high-level nuclear waste package containers in a salt repository environment. The corrosion rate of carbon steels in moderately acidic aqueous chloride environments obeys an Arrhenius dependence on temperature and a (pH{sub 2}){sup {minus}1/2} dependence on hydrogen partial pressure. The cathodic reduction of water to produce hydrogen is the rate-controlling step in the corrosion process. An expression for the corrosion rate incorporating these two dependencies was used to estimate the corrosion life of several proposed waste package configurations. 42 refs., 11 figs., 2 tabs.

  5. Stability and electrokinetic potential of aqueous graphite dispersions in solutions of polyvalent metal salts

    SciTech Connect

    Morarv, V.N.; Ovcharenko, F.D.

    1986-07-01

    Three changes in the charge sign of graphite in AlCl/sub 3/ solutions in the pH interval 2-12 and alternation of several zones of stability and coagulation of the dispersions are explained by taking into consideration the hydrolysis and complex formation of Al/sup 3 +/ ions, as well as the character of ionization of the solid-phase groups. Convincing proof has been obtained that it is not the simple Al/sup 3 +/ ions but their hydrolysis products which are capable of altering the charge of the graphite surface. The coagulating and stabilizing power of the aluminum ions depends on their state in solution.

  6. Effect of plasticizer on surface of free films prepared from aqueous solutions of salts of cationic polymers with different plasticizers

    NASA Astrophysics Data System (ADS)

    Bajdik, János; Fehér, Máté; Pintye-Hódi, Klára

    2007-06-01

    Acquisition of a more detailed understanding of all technological processes is currently a relevant tendency in pharmaceutical technology and hence in industry. A knowledge of film formation from dispersion of polymers is very important during the coating of solid dosage forms. This process and the structure of the film can be influenced by different additives. In the present study, taste-masking films were prepared from aqueous citric acid solutions of a cationic polymer (Eudragit ® E PO) with various hydrophilic plasticizers (glycerol, propylene glycol and different poly(ethylene glycols)). The mechanical properties, film thickness, wetting properties and surface free energy of the free films were studied. The aim was to evaluate the properties of surface of free films to predict the arrangement of macromolecules in films formed from aqueous solutions of salts of cationic polymers. A high molecular weight of the plasticizer decreased the work of deformation. The surface free energy and the polarity were highest for the film without plasticizer; the hydrophilic additives decreased these parameters. The direction of the change in polarity (a hydrophilic component caused a decrease in the polarity) was unexpected. It can be explained by the change in orientation of the macromolecules, a hydrophobic surface being formed. Examination of the mechanical properties and film thickness can furnish additional results towards a knowledge of film formation by this not frequently applied type of polymer from aqueous solution.

  7. Effects of solution conditions and surface chemistry on the adsorption of three recombinant botulinum neurotoxin antigens to aluminum salt adjuvants.

    PubMed

    Vessely, Christina; Estey, Tia; Randolph, Theodore W; Henderson, Ian; Nayar, Rajiv; Carpenter, John F

    2007-09-01

    Botulinum neurotoxin (BoNT) is a biological warfare threat. Protein antigens have been developed against the seven major BoNT serotypes for the development of a recombinant protein vaccine. This study is an evaluation of adsorption profiles for three of the recombinant protein antigens to aluminum salt adjuvants in the development of a trivalent vaccine against BoNT. Adsorption profiles were obtained over a range of protein concentrations. The results document that charge-charge interactions dominate the adsorption of antigen to adjuvant. Optimal conditions for adsorption were determined. However, potency studies and solution stability studies indicated the necessity of using aluminum hydroxide adjuvant at low pH. To improve the adsorption profiles to AlOH adjuvant, phosphate ions were introduced into the adsorption buffers. The resulting change in the adjuvant chemistry led to an improvement of adsorption of the BoNT antigens to aluminum hydroxide adjuvant while maintaining potency. Competitive adsorption profiles were also determined, and showed changes in maximum adsorption from mixed solutions compared to adsorption from individual protein solutions. The adsorption profiles for each protein varied due to differences in adsorption mechanism and affinity for the adjuvant surface. These results emphasize the importance of evaluating competitive adsorption in the development of multivalent vaccine products. (c) 2007 Wiley-Liss, Inc. and the American Pharmacists Association.

  8. Biomass production in agroforestry and forestry systems on salt-affected soils in South Asia: exploration of the GHG balance and economic performance of three case studies.

    PubMed

    Wicke, Birka; Smeets, Edward M W; Akanda, Razzaque; Stille, Leon; Singh, Ranjay K; Awan, Abdul Rasul; Mahmood, Khalid; Faaij, Andre P C

    2013-09-30

    This study explores the greenhouse gas balance and the economic performance (i.e. net present value (NPV) and production costs) of agroforestry and forestry systems on salt-affected soils (biosaline (agro)forestry) based on three case studies in South Asia. The economic impact of trading carbon credits generated by biosaline (agro)forestry is also assessed as a potential additional source of income. The greenhouse gas balance shows carbon sequestration over the plantation lifetime of 24 Mg CO2-eq. ha(-1) in a rice-Eucalyptus camaldulensis agroforestry system on moderately saline soils in coastal Bangladesh (case study 1), 6 Mg CO2-eq. ha(-1) in the rice-wheat- Eucalyptus tereticornis agroforestry system on sodic/saline-sodic soils in Haryana state, India (case study 2), and 96 Mg CO2-eq. ha(-1) in the compact tree (Acacia nilotica) plantation on saline-sodic soils in Punjab province of Pakistan. The NPV at a discount rate of 10% is 1.1 k€ ha(-1) for case study 1, 4.8 k€ ha(-1) for case study 2, and 2.8 k€ ha(-1) for case study 3. Carbon sequestration translates into economic values that increase the NPV by 1-12% in case study 1, 0.1-1% in case study 2, and 2-24% in case study 3 depending on the carbon credit price (1-15 € Mg(-1) CO2-eq.). The analysis of the three cases indicates that the economic performance strongly depends on the type and severity of salt-affectedness (which affect the type and setup of the agroforestry system, the tree species and the biomass yield), markets for wood products, possibility of trading carbon credits, and discount rate. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Small-angle X-ray scattering from salt-free solutions of star-branched polyelectrolytes

    NASA Astrophysics Data System (ADS)

    Heinrich, M.; Rawiso, M.; Zilliox, J. G.; Lesieur, P.; Simon, J. P.

    2001-02-01

    The dispersion state of sodium-sulphonated polystyrene (ensuremathNaPSS) star-branched polyelectrolytes was investigated in salt-free aqueous solutions, by use of the small-angle X-ray scattering technique. With respect to polystyrene (PS) star-branched polymers of identical functionality, the ordering phenomenon occurring in the neighborhood of the overlap concentration c^* is reinforced and observed in a larger range of concentrations. Moreover, the degree of order is no longer maximum at c^* and is improved as the concentration decreases. The dispersion state is then mainly controlled by the electrostatic interaction. A crystalline order should therefore be achieved with stars of lower functionality, provided the electrostatic interaction is added to the osmotic repulsion. On the other hand, unusual scattering patterns are measured for aqueous solutions of ensuremathNaPSS star polyelectrolytes. Indeed, a diffuse scattering is revealed at high angles, in addition to the regular diffraction rings related to preferred interstar distances. It is similar to the broad scattering peak produced by semidilute solutions of ensuremathNaPSS linear polyelectrolytes and associated to the electrostatic correlation hole within the isotropic model. In the dilute regime (c< c^*), it is just an intramolecular characteristic and represents the electrostatic repulsion between arms belonging to the same star. In the semidilute regime (c> c^*), it also reflects the electrostatic repulsion between arms of distinct stars. So, as the concentration increases, it is mainly caused by the interpenetration of ensuremathNaPSS stars. Such an observation is in agreement with the composite structure earlier proposed by Daoud and Cotton for star semidilute solutions. For c> c^*, ensuremathNaPSS star aqueous solutions can therefore be pictured as effective stars immersed in a matrix formed by the overlap of the arm ends. With respect to the dilute regime, the effective stars are smaller; the higher

  10. Improving Loading Amount and Performance of Quantum Dot-Sensitized Solar Cells through Metal Salt Solutions Treatment on Photoanode.

    PubMed

    Wang, Wenran; Du, Jun; Ren, Zhenwei; Peng, Wenxiang; Pan, Zhenxiao; Zhong, Xinhua

    2016-11-16

    Increasing QD loading amount on photoanode and suppressing charge recombination are prerequisite for high-efficiency quantum dot-sensitized solar cells (QDSCs). Herein, a facile technique for enhancing the loading amount of QDs on photoanode and therefore improving the photovoltaic performance of the resultant cell devices is developed by pipetting metal salt aqueous solutions on TiO2 film electrode and then evaporating at elevated temperature. The effect of different metal salt solutions was investigated, and experimental results indicated that the isoelectric point (IEP) of metal ions influenced the loading amount of QDs and consequently the photovoltaic performance of the resultant cell devices. The influence of anions was also investigated, and the results indicated that anions of strong acid made no difference, while acetate anion hampered the performance of solar cells. Infrared spectroscopy confirmed the formation of oxyhydroxides, whose behavior was responsible for QD loading amount and thus solar cell performance. Suppressed charge recombination based on Mg(2+) treatment under optimal conditions was confirmed by impedance spectroscopy as well as transient photovoltage decay measurement. Combined with high-QD loading amount and retarded charge recombination, the champion cell based on Mg(2+) treatment exhibited an efficiency of 9.73% (Jsc = 27.28 mA/cm(2), Voc = 0.609 V, FF = 0.585) under AM 1.5 G full 1 sun irradiation. The obtained efficiency was one of the best performances for liquid-junction QDSCs, which exhibited a 10% improvement over the untreated cells with the highest efficiency of 8.85%.

  11. Movements of sodium and potassium into ejaculated boar spermatozoa suspended in seminal plasma and a biological salt solution.

    PubMed

    Crabo, B G; Zimmerman, K J; Moore, R; Thornburgh, F H

    1976-10-22

    Uptake of 22Na and 42K into ejaculated boar spermatozoa was measured in vitro. Cells were suspended either in seminal plasma or in a biological salt solution of essentially the same composition as boar seminal plasma. Samples were incubated at 30 degrees C. Correction was made for extracellular space in the centrifuged sperm pellet. This was determined as 22Na-space, which was less (P less than 0.001) than [14C] carboxyinulin space. Large differences were observed among individual ejaculates. The half-time for potassium uptake into the spermatozoa averaged 11.5 min, which is much faster than that for leukocytes or erythrocytes. When the spermatozoa were suspended in the biological salt solution, the initial rate of 42K uptake was significantly decreased. This may be due to disturbances of the protein components of the sperm membrane. The uptake of 22Na into the spermatozoa was slow. Sodium and potassium transport appeared not to be coupled in the 3/2 ratio which has been reported for erythrocyte membranes. The average concentration of sodium was 108 mM in seminal plasma and 26 mM in the spermatozoa (112 mmol/kg water and 38 mmol/kg water, respectively). The corresponding figures for potassium were 26 mM and 51 mM (27 mmol/kg water and 74 mmol/kg water). The random error for a single determination for the various methods used varied between 2.4 and 13.3% of the mean.

  12. Influence of arbuscular mycorrhiza on organic solutes in maize leaves under salt stress.

    PubMed

    Sheng, Min; Tang, Ming; Zhang, Fengfeng; Huang, Yanhui

    2011-07-01

    A pot experiment was conducted to examine the effect of the arbuscular mycorrhizal (AM) fungus, Glomus mosseae, on plant biomass and organic solute accumulation in maize leaves. Maize plants were grown in sand and soil mixture with three NaCl levels (0, 0.5, and 1.0 g kg(-1) dry substrate) for 55 days, after 15 days of establishment under non-saline conditions. At all salinity levels, mycorrhizal plants had higher biomass and higher accumulation of organic solutes in leaves, which were dominated by soluble sugars, reducing sugars, soluble protein, and organic acids in both mycorrhizal and non-mycorrhizal plants. The relative abundance of free amino acids and proline in total organic solutes was lower in mycorrhizal than in non-mycorrhizal plants, while that of reducing sugars was higher. In addition, the AM symbiosis raised the concentrations of soluble sugars, reducing sugars, soluble protein, total organic acids, oxalic acid, fumaric acid, acetic acid, malic acid, and citric acid and decreased the concentrations of total free amino acids, proline, formic acid, and succinic acid in maize leaves. In mycorrhizal plants, the dominant organic acid was oxalic acid, while in non-mycorrhizal plants, the dominant organic acid was succinic acid. All the results presented here indicate that the accumulation of organic solutes in leaves is a specific physiological response of maize plants to the AM symbiosis, which could mitigate the negative impact of soil salinity on plant productivity.

  13. Self-assembly of regular hollow icosahedra in salt-free catanionic solutions.

    PubMed

    Dubois, M; Demé, B; Gulik-Krzywicki, T; Dedieu, J C; Vautrin, C; Désert, S; Perez, E; Zemb, T

    2001-06-07

    Self-assembled structures having a regular hollow icosahedral form (such as those observed for proteins of virus capsids) can occur as a result of biomineralization processes, but are extremely rare in mineral crystallites. Compact icosahedra made from a boron oxide have been reported, but equivalent structures made of synthetic organic components such as surfactants have not hitherto been observed. It is, however, well known that lipids, as well as mixtures of anionic and cationic single chain surfactants, can readily form bilayers that can adopt a variety of distinct geometric forms: they can fold into soft vesicles or random bilayers (the so-called sponge phase) or form ordered stacks of flat or undulating membranes. Here we show that in salt-free mixtures of anionic and cationic surfactants, such bilayers can self-assemble into hollow aggregates with a regular icosahedral shape. These aggregates are stabilized by the presence of pores located at the vertices of the icosahedra. The resulting structures have a size of about one micrometre and mass of about 1010 daltons, making them larger than any known icosahedral protein assembly or virus capsid. We expect the combination of wall rigidity and holes at vertices of these icosahedral aggregates to be of practical value for controlled drug or DNA release.

  14. Electrophoretic mobilities of neutral analytes and electroosmotic flow markers in aqueous solutions of Hofmeister salts.

    PubMed

    Křížek, Tomáš; Kubíčková, Anna; Hladílková, Jana; Coufal, Pavel; Heyda, Jan; Jungwirth, Pavel

    2014-03-01

    Small neutral organic compounds have traditionally the role of EOF markers in electrophoresis, as they are expected to have zero electrophoretic mobility in external electric fields. The BGE contains, however, ions that have unequal affinities to the neutral molecules, which in turn results in their mobilization. In this study we focused on two EOF markers-thiourea and DMSO, as well as on N-methyl acetamide (NMA) as a model of the peptide bond. By means of CE and all atom molecular dynamics simulations we explored mobilization of these neutral compounds in large set of Hofmeister salts. Employing a statistical mechanics approach, we were able to reproduce by simulations the experimental electrophoretic mobility coefficients. We also established the role of the chemical composition of marker and the BGE on the measured electrophoretic mobility coefficient. For NMA, we interpreted the results in terms of the relative affinities of cations versus anions to the peptide bond. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. PPh4Cl in aqueous solution - the aggregation behavior of an antagonistic salt.

    PubMed

    Winkler, Robert; Buchecker, Thomas; Hastreiter, Florian; Touraud, Didier; Kunz, Werner

    2017-09-13

    The initial definition of hydrotropy by Neuberg in 1916 describes a hydrotrope as a molecule which enhances the solubilization of hydrophobic substances in water. Sodium dodecyl sulfate (SDS) and sodium xylene sulfonate (SXS) are typical representatives fulfilling this old definition. They are either surfactants with a critical micellar concentration (CMC) or hydrotropes in the current sense of the term, showing a minimum hydrotrope concentration (MHC), respectively. In the present contribution, we consider the antagonistic salt PPh4Cl as a hydrotrope. Surface tension measurements and solubilization experiments on a hydrophobic dye confirm the solubilization behavior of PPh4Cl, which is in-between the one of SDS and SXS. With the help of scattering techniques (DLS, SLS, SAXS), NMR and conductivity measurements, we show that in contrast to SDS as a hydrotrope with an inherent CMC, PPh4Cl does not exhibit mesoscale aggregation. Therefore, PPh4Cl can be classified rather as a hydrotrope in the modern sense, with an inherent MHC just as SXS.

  16. Influence of pH, temperature, and concentration on stabilization of aqueous hornet silk solution and fabrication of salt-free materials.

    PubMed

    Kameda, Tsunenori

    2015-01-01

    We found that an aqueous solution of silk from cocoons produced by hornet larvae (hornet silk) can be obtained when the solution is adjusted to basic conditions of pH > 9.2. It is known that native hornet cocoons can be dissolved in concentrated aqueous solution of salts, such as lithium bromide (LiBr) and calcium chloride (CaCl2). Upon the removal of these salts from solution by dialysis, solidification, gelation, or sedimentation of hornet silk is known to occur. In the present study, under basic conditions, however, no such solidification occurred, even after salt removal. In this study, ammonia was used for alkalization of solution because it is volatilized during the casting process and pure hornet silk materials can be obtained after drying. The effects of the concentrations of hornet silk and ammonia, as well as dialysis temperature, on preventing gelation during dialysis were investigated. Dialysis conditions that limit the degradation of hornet silk by hydrolysis in alkali solution were identified. Moreover, casting conditions to prepare flexible and transparent hornet silk film from aqueous ammonia solution were optimized. Molecular structural analysis of hornet silk in aqueous ammonia solution and cast film indicated the formation of α-helix conformations.

  17. Removal of arsenic(III) and arsenic(IV) ions from aqueous solutions with lanthanum(III) salt and comparison with aluminum(III), calcium(II), and iron(III) salts

    SciTech Connect

    Tokunaga, S.; Yokoyama, S.; Wasay, S.A.

    1999-05-01

    Interactions of arsenic(III) and arsenic(V) ions with a lanthanum salt were studied with the aim of developing a new precipitation method for removal of arsenic from aqueous solutions. Performance was compared to those of aluminum, polyaluminum chloride (PAC), calcium, and iron(III) salts. Arsenic(III) was removed by iron(III) and lanthanum in a narrow pH range with less than 605 removal. Arsenic(V) was removed more efficiently by aluminum, PAC, iron(III), and lanthanum. Lanthanum was most effective, meeting Japanese effluent and drinking water standards by adding three times as much lanthanum as arsenic(V).

  18. Technology Solutions Case Study: Balancing Hydronic Systems in Multifamily Buildings, Chicago, Illinois

    SciTech Connect

    2014-09-01

    In multifamily building hydronic systems, temperature imbalance may be caused by undersized piping, improperly adjusted balancing valves, inefficient water temperature and flow levels, and owner/occupant interaction with the boilers, distribution and controls. The effects of imbalance include tenant discomfort, higher energy use intensity and inefficient building operation. In this case study , Partnership for Advanced Residential Retrofit and Elevate Energy. explores cost-effective distribution upgrades and balancing measures in multifamily hydronic systems, providing a resource to contractors, auditors, and building owners on best practices to improve tenant comfort and lower operating costs.

  19. The equilibrium structure of lithium salt solutions in ether-functionalized ammonium ionic liquids.

    PubMed

    Figueiredo, Pedro Henrique; Siqueira, Leonardo J A; Ribeiro, Mauro C C

    2012-10-11

    Molecular dynamics simulations have been performed for ionic liquids based on a ternary mixture of lithium and ammonium cations and a common anion, bis(trifluoromethylsulfonyl)imide, [Tf(2)N](-). We address structural changes resulting from adding Li(+) in ionic liquids with increasing length of an ether-functionalized chain in the ammonium cation. The calculation of static structure factors reveals the lithium effect on charge ordering and intermediate range order in comparison with the neat ionic liquids. The charge ordering is modified in the lithium solution because the coordination of [Tf(2)N](-) toward Li(+) is much stronger than ammonium cations. Intermediate range order is observed in neat ionic liquids based on ammonium cations with a long chain, but in the lithium solutions, there is also a nonhomogenous distribution of Li(+) cations. The presence of Li(+) enhances interactions between the ammonium cations due to correlations between the oxygen atom of the ether chain and the nitrogen atom of another ammonium cation.

  20. Size and shape of charged micelles of ionic surfactants in aqueous salt solutions.

    PubMed

    Ikeda, S; Ozeki, S; Hayashi, S

    1980-06-01

    Light-scattering has been measured on aqueous NaCl solutions of dodecyldimethylammonium chloride and sodium dodecyl sulfate. From molecular weight determination it is confirmed that spherical micelles are formed at low NaCl concentrations, but at high NaCl concentrations the small micelles formed at the critical micelle concentration further associate to form large rod-like micelles with increasing micelle concentration. The reduction of repulsion between charged groups induces the sphere-rod transition of micelle shape. The dependence of molecular weight on ionic strength can be expressed by double logarithmic relations, which are dependent on the micelle shape. While dodecyldimethylammonium chloride dissolves even in 4.00 M NaCl, sodium dodecyl sulfate solutions exhibit some XXX in angular dissymmetry at NaCl concentrations higher than 0.50 M at low temperatures.

  1. Phase behavior and in-situ density determination in concentrated salt solutions under hydrothermal conditions

    SciTech Connect

    Anderson, G.

    1994-10-01

    An optical cell was constructed to observe phase behavior in aqueous electrolyte solutions at temperatures up to 450{degrees}C and pressures up to 1200 bar. The goal was to map out the single-phase region for a certain concentrated, multicomponent waste solution, to aid in the design of a treatment facility. The imaging system could also measure the refractive index of the fluid, allowing the density to be determined by means of the Lorentz-Lorenz relationship. The validity of the technique was verified for pure water and for NaCl-water systems. Data for a multicomponent system is present as a family plot of density vs. pressure, for several different temperatures, with the lowest pressure on each plot corresponding to a phase boundary. Data is also presented for the binary system NaNO{sub 3}-water.

  2. On-ice sweat rate, voluntary fluid intake, and sodium balance during practice in male junior ice hockey players drinking water or a carbohydrate-electrolyte solution.

    PubMed

    Palmer, Matthew S; Logan, Heather M; Spriet, Lawrence L

    2010-06-01

    This study evaluated the repeatability of hydration and sweat measurements taken during on-ice hockey practices with players drinking only water, and determined whether having only a carbohydrate-electrolyte solution (CES) to drink during practices decreased fluid intake or affected other hydration and (or) sweat measures. All testing was conducted on elite players of an Ontario Hockey League team (+/-SE; mean age, 17.6 +/- 0.3 years; mean height, 182.9 +/- 1.4 cm; mean body mass, 83.0 +/- 1.7 kg). Players were studied 3 times over the course of 6 weekly on-ice practices (+/-SE; mean playing time, 1.58 +/- 0.07 h; mean temperature, 11.4 +/- 0.8 degrees C; mean relative humidity, 52% +/- 3%). There was strong repeatability of the measured hydration and sweat parameters between 2 similar on-ice practices when players drank only water. Limiting the players to drinking only a CES (as opposed to water) did not decrease fluid intake during practice (+/-SE; mean CES intake, 0.72 +/- 0.07 L.h-1 vs. mean water intake, 0.82 +/- 0.08 L.h-1) or affect sweat rate (1.5 +/- 0.1 L.h-1 vs. 1.5 +/- 0.1 L.h-1), sweat sodium concentration (72.4 +/- 5.6 mmol.L-1 vs. 73.0 +/- 4.4 mmol.L-1), or percent body mass loss (1.1% +/- 0.2% vs. 0.9% +/- 0.2%). Drinking a CES also improved sodium balance (-2.1 +/- 0.2 g.h-1 vs. -2.6 +/- 0.3 g.h-1) and provided the players with a significant carbohydrate (43 +/- 4 g.h-1 vs. 0 +/- 0 g.h-1) during practice. In summary, a single field sweat test during similar on-ice hockey practices in male junior hockey players is sufficient to evaluate fluid and electrolyte balance. Also, a CES does not affect voluntary fluid intake during practice, compared with water, in these players. The CES provided some salt to offset the salt lost in sweat, and carbohydrate, which may help maintain physical and mental performance in the later stages of practice.

  3. Mechanism of Pitting Corrosion Prevention by Nitrite in Carbon Steel Exposed to Dilute Salt Solutions

    SciTech Connect

    Philip E. Zapp; John W. Van Zee

    2002-02-01

    The research has developed a broad fundamental understanding of the inhibition action of nitrite ions in preventing nitrate pitting corrosion of carbon steel tanks containing high-level radioactive waste. This fundamental understanding can be applied to specific situations during waste removal for permanent disposition and waste tank closure to ensure that the tanks are maintained safely. The results of the research provide the insight necessary to develop solutions that prevent further degradation.

  4. Growth of lithium triborate single crystals from molten salt solution under various temperature gradients

    NASA Astrophysics Data System (ADS)

    Guretskii, S. A.; Ges, A. P.; Zhigunov, D. I.; Ignatenko, A. A.; Kalanda, N. A.; Kurnevich, L. A.; Luginets, A. M.; Milovanov, A. S.; Molchan, P. V.

    1995-12-01

    Single crystals of lithium triborate LiB 3O 5 (LBO) have been grown by the top-seeded solution growth method with B 2O 3 as a solvent using different temperature gradients in the zone of crystallization. Optical and nonlinear optical properties of LBO single crystals have been investigated. The influence of post-growth thermal treatment in oxygen atmosphere on the optical properties has been studied.

  5. Texture and microstructure properties of frozen chicken breasts pretreated with salt and phosphate solutions.

    PubMed

    Yoon, K S

    2002-12-01

    This study investigated the effects of 10% NaCl, trisodium phosphate (TSP), sodium tripolyphosphate (STPP), and tetrapotassium pyrophosphate (TKPP) treatments on textural and microstructural properties of chicken breasts during 10 mo of frozen storage at -20 C. Fresh chicken breasts were treated for 10 min with 10% NaCl and various phosphate solutions, including TSP, STPP, and TKPP, and stored in a -20 C freezer for 10 mo. Frozen chicken breasts were completely thawed at 4 C and oven-baked at 177 C for 20 min. Shear force, drip loss, and cooking loss were measured. In addition, ice crystal formation and structure changes of frozen chicken breasts during storage were evaluated using transmission electron microscopy (TEM). Treating chicken breasts with 10% TSP and STPP solution significantly reduced drip and cooking losses as well as minimized ice crystal formation and freeze-induced shrinkage of myofibrils. No significant texture toughening was observed in frozen chicken breasts regardless of treatments. These results suggest that the perceived quality losses of frozen chicken breast were not associated with texture toughening. The water-binding ability of chicken meat was the most important factor in maintaining the quality of chicken breast during extended frozen storage, which can be accomplished by treating chicken breasts with 10% TSP and STPP solutions before frozen storage.

  6. Helix-specific interactions induce condensation of guanosine four-stranded helices in concentrated salt solutions.

    PubMed

    Mariani, P; Ciuchi, F; Saturni, L

    1998-01-01

    Deoxyguanosine-5'-monophosphate in water self-associates into stable structures, which include liquid-crystalline hexagonal and cholesteric phases. The structural unit is a four-stranded helix, composed of stacked Hoogsteen-bonded guanosine quartets. By using the osmotic stress method, we recently measured the force between helices in KCl solutions up to 2 M. In addition to the long-range electrostatic force, a short-range hydration repulsive contribution was recognized. The hydration repulsion is exponential, and shows a decay length independent from the ionic strength of the solution. Here, we report that more concentrated KCl solutions cause condensation of the guanosine helix in a hexagonal phase with constant equilibrium separation of approximately 7 A between helix surfaces. Long-range attraction, which induces the self-assembly, and short-range repulsion, which prevents the contact between the helices, are implied. By using osmotic stress, the force needed to push helices closer from the spontaneously assumed position has been measured. The attractive force was then estimated as a difference between the net force and the repulsive contribution, revealing an exponential decay length about two times larger than that of the short-range repulsion. The agreement with the helix interaction theory introduced recently by Kornyshev and Leikin (Kornyshev, A. A., and S. Leikin, 1997. Theory of interaction between helical molecules. J. Phys. Chem. 107:3656-3674) suggests that the repulsive and attractive forces originate from helix-specific interactions.

  7. Tank Waste Transport Stability: Summaries of Hanford Slurry and Salt-Solution Studies in FY 2000

    SciTech Connect

    Welch, T.D.

    2002-07-08

    This report is a collection of summary articles on FY 2000 studies of slurry transport and salt-well pumping related to Hanford tank waste transfers. These studies are concerned with the stability (steady, uninterrupted flow) of tank waste transfers, a subset of the Department of Energy (DOE) Tanks Focus Area Tank (TFA) Waste Chemistry effort. This work is a collaborative effort of AEA Technology plc, the Diagnostic Instrumentation and Analysis Laboratory at Mississippi State University (DIAL-MSU), the Hemispheric Center for Environmental Technology at Florida International University (HCET-FIU), Numatec Hanford Corporation (NHC), and the Oak Ridge National Laboratory (ORNL). The purpose of this report is to provide, in a single document, an overview of these studies to help the reader identify contacts and resources for obtaining more detailed information and to help promote useful interchanges between researchers and users. Despite over 50 years of experience in transporting radioactive tank wastes to and from equipment and tanks at the Department of Energy's Hanford, Savannah River, and Oak Ridge sites, waste slurry transfer pipelines and process piping become plugged on occasion. At Hanford, several tank farm pipelines are no longer in service because of plugs. At Savannah River, solid deposits in the outlet line of the 2H evaporator have resulted in an unplanned extended downtime. Although waste transfer criteria and guidelines intended to prevent pipeline plugging are in place, they are not always adequate. To avoid pipeline plugging in the future, other factors that are not currently embodied in the transfer criteria may need to be considered. The work summarized here is being conducted to develop a better understanding of the chemical and waste flow dynamics during waste transfer. The goal is to eliminate pipeline plugs by improving analysis and engineering tools in the field that incorporate this understanding.

  8. OSMOTIC COEFFICIENTS, SOLUBILITIES, AND DELIQUESCENCE RELATIONS IN MIXED AQUEOUS SALT SOLUTIONS AT ELEVATED TEMPERATURE

    SciTech Connect

    M.S. Gruszkiewicz; D.A. Palmer

    2006-02-22

    While thermodynamic properties of pure aqueous electrolytes are relatively well known at ambient temperature, there are far fewer data for binary systems extending to elevated temperatures and high concentrations. There is no general theoretically sound basis for prediction of the temperature dependence of ionic activities, and consequently temperature extrapolations based on ambient temperature data and empirical equations are uncertain and require empirical verification. Thermodynamic properties of mixed brines in a wide range of concentrations would enhance the understanding and precise modeling of the effects of deliquescence of initially dry solids in humid air in geological environments and in modeling the composition of waters during heating, cooling, evaporation or condensation processes. These conditions are of interest in the analysis of waters on metal surfaces at the proposed radioactive waste repository at Yucca Mountain, Nevada. The results obtained in this project will be useful for modeling the long-term evolution of the chemical environment, and this in turn is useful for the analysis of the corrosion of waste packages. In particular, there are few reliable experimental data available on the relationship between relative humidity and composition that reveals the eutonic points of the mixtures and the mixture deliquescence RH. The deliquescence RH for multicomponent mixtures is lower than that of pure component or binary solutions, but is not easy to predict quantitatively since the solutions are highly nonideal. In this work we used the ORNL low-temperature and high-temperature isopiestic facilities, capable of precise measurements of vapor pressure between ambient temperature and 250 C for determination of not only osmotic coefficients, but also solubilities and deliquescence points of aqueous mixed solutions in a range of temperatures. In addition to standard solutions of CaCl{sub 2}, LiCl, and NaCl used as references, precise direct

  9. Applications of homogenous balanced principle on investigating exact solutions to a series of time fractional nonlinear PDEs

    NASA Astrophysics Data System (ADS)

    Rui, Weiguo

    2017-06-01

    By using a counterexample, we proved the fractional chain rule appeared in many references does not hold under Riemann-Liouville definition and Caputo definition of fractional derivative. It shows that this chain rule is invalid in investigating exact solutions of nonlinear fractional partial differential equations (PDEs). In this paper, based on the homogenous balanced principle, the function-expansion method of separation variable type are introduced. By using this method, a series of nonlinear time fractional PDEs such as time fractional KdV equation and Burgers equation, time fractional diffusion-convection equations are studied from mathematical viewpoint. The dynamical properties of these exact solutions are discussed and the profiles of several representative exact solutions are illustrated.

  10. A balanced approach: Dr. Biswell's solution to fire issues in urban interface and wildland ecosystems

    Treesearch

    Carol Rice

    1995-01-01

    Dr. Biswell's approach to fire management balanced fire prevention, suppression, and fuel management. Dr. Biswell maintained that with increased support for fire prevention and fuel management, several profound changes would be anticipated, including a decrease in the number of wildfires, as well as a decrease in requirements for suppression. Interested persons...

  11. Ionoregulatory and endocrine responses to disturbed salt and water balance in Mozambique tilapia exposed to confinement and handling stress.

    PubMed

    Breves, Jason P; Hirano, Tetsuya; Grau, E Gordon

    2010-03-01

    This study assessed the endocrine and ionoregulatory responses by tilapia (Oreochromis mossambicus) to disturbances of hydromineral balance during confinement and handling. In fresh water (FW), confinement and handling for 0.5, 1, 2 and 6h produced elevations in plasma cortisol and glucose; a reduction in plasma osmolality was observed at 6h. Elevations in plasma prolactins (PRL(177) and PRL(188)) accompanied this fall in osmolality while no effect upon growth hormone (GH) was evident; an increase in insulin-like growth-factor I (IGF-I) occurred at 0.5h. In seawater (SW), confinement and handling increased plasma osmolality and glucose between 0.5 and 6h; no effect on plasma cortisol was seen due to variable control levels. Concurrently, both PRLs were reduced in stressed fish with only transient changes in the GH/IGF-I axis. Next, the branchial expression of Na(+)/K(+)/2Cl(-) cotransporter (NKCC) and Na(+)/Cl(-) cotransporter (NCC) was characterized following confinement and handling for 6h. In SW, NKCC mRNA levels increased in stressed fish concurrently with elevated plasma osmolality and diminished gill Na(+), K(+)-ATPase activity; NCC was unchanged in stressed fish irrespective of salinity. Taken together, PRL and NKCC participate in restoring osmotic balance during acute stress while the GH/IGF-I axis displays only modest responses. Copyright 2009 Elsevier Inc. All rights reserved.

  12. Process for preparing chemically modified micas for removal of cesium salts from aqueous solution

    DOEpatents

    Yates, Stephen Frederic; DeFilippi, Irene; Gaita, Romulus; Clearfield, Abraham; Bortun, Lyudmila; Bortun, Anatoly

    2000-09-05

    A chemically modified mica composite formed by heating a trioctahedral mica in an aqueous solution of sodium chloride having a concentration of at least 1 mole/liter at a temperature greater than 180 degrees Centigrade for at least 20 hours, thereby replacing exchangeable ions in the mica with sodium. Formation is accomplished at temperatures and pressures which are easily accessed by industrial equipment. The reagent employed is inexpensive and non-hazardous, and generates a precipitate which is readily separated from the modified mica.

  13. Comparative ion insertion study into a nanostructured vanadium oxide in aqueous salt solutions

    SciTech Connect

    Yuan, Q.; Ren, S. L.; Zukowski, J.; Pomeroy, M.; Soghomonian, V.

    2014-07-07

    We present a comparative study for the electrochemical insertion of different cations into a nanostructured vanadium oxide material. The oxide is hydrothemally synthesized and electrically characterized by variable temperature measurements. The electrochemical reactions are performed in aqueous chloride solutions of lithium, sodium, potassium, and ammonium, and the electrochemical behavior of various cycles are correlated with visual changes in the vanadium oxide nanosheets as observed by scanning electron microscopy. We note an increase in the specific charge per cycle in the cases of sodium and ammonium ions only, correlated with minimal physical changes to the nanosheets. The differing behavior of the various ions has implications for their use in electrical energy storage applications.

  14. Partitioning of mobile ions between ion exchange polymers and aqueous salt solutions: importance of counter-ion condensation.

    PubMed

    Kamcev, Jovan; Galizia, Michele; Benedetti, Francesco M; Jang, Eui-Soung; Paul, Donald R; Freeman, Benny D; Manning, Gerald S

    2016-02-17

    Equilibrium partitioning of ions between a membrane and a contiguous external solution strongly influences transport properties of polymeric membranes used for water purification and energy generation applications. This study presents a theoretical framework to quantitatively predict ion sorption from aqueous electrolytes (e.g., NaCl, MgCl2) into charged (i.e., ion exchange) polymers. The model was compared with experimental NaCl, MgCl2, and CaCl2 sorption data in commercial cation and anion exchange membranes. Ion sorption in charged polymers was modeled using a thermodynamic approach based on Donnan theory coupled with Manning's counter-ion condensation theory to describe non-ideal behavior of ions in the membrane. Ion activity coefficients in solution were calculated using the Pitzer model. The resulting model, with no adjustable parameters, provides remarkably good agreement with experimental values of membrane mobile salt concentration. The generality of the model was further demonstrated using literature data for ion sorption of various electrolytes in charged polymers, including HCl sorption in Nafion.

  15. Solution-based approaches for making high-density sodalite waste forms to immobilize spent electrochemical salts

    SciTech Connect

    Lepry, William C.; Riley, Brian J.; Crum, Jarrod V.; Rodriguez, Carmen P.; Pierce, David A.

    2013-08-29

    Three different solution-based approaches were taken to make sodalite minerals as a host for a mixed salt simulating the waste generated during the electrochemical separations process of nuclear fuel reprocessing that contains alkali, alkaline earth, and lanthanide chlorides plus trace iodine and actinides. All of the approaches included an aqueous solution of mixed chlorides (simulated waste) but the other reactants varied: (1) Al(OH)3 + NaOH + CS, (2) NaAlO2 + CS, and (3) Al2Si2O7 + NaOH, (CS = colloidal silica). The products were dried, ground, pressed into pellets, fired (650–950 °C), and characterized. Both 5 and 10 mass% of a Si-Na-B glass binder were introduced at different stages in the process. Route (2) proved the most successful at producing high sodalite fractions (up to 100%) with minimal glass binder additions and showed high consolidation potential (up to 91.4% of theoretical density). Detailed comparisons are provided of the results.

  16. Study of quantitative interactions of potato and corn starch granules with ions in diluted solutions of heavy metal salts.

    PubMed

    Szymońska, Joanna; Molenda, Marcin; Wieczorek, Jerzy

    2015-12-10

    Interactions of potato and corn starch granules with ions in diluted solutions of silver, lead, copper or iron salts were investigated. It was shown experimentally that granules accumulated the cations in amounts depending on the granule structure and water content as well as a type of both metal and counter-ions present in solution. Potato starch retained almost three times more cations compared to corn starch what was proportional to the total phosphorous content in these starches. Quantity of milligrams of cations bound by 1g of starch was inversely correlated with the cation hydration. Ag(+), Pb(2+) and Cu(2+) were connected in stoichiometric amounts of moles to semicrystalline and amorphous parts of the granules. Fe(3+) ions were accumulated in higher than stoichiometric quantities mainly in granule amorphous regions. Metal ions penetrated into granules together with anions except nitrates which remained on surface of potato starch granules. Cations facilitated the starch thermal decomposition in accordance with values of their standard redox potentials. Nitrates supported this process only in the presence of base metal cations.

  17. Unusual Salt and pH Induced Changes in Polyethylenimine Solutions

    PubMed Central

    Millard, Paul; Basu, Saswati; Horkay, Ferenc; Chandran, Preethi L

    2016-01-01

    Linear PEI is a cationic polymer commonly used for complexing DNA into nanoparticles for cell-transfection and gene-therapy applications. The polymer has closely-spaced amines with weak-base protonation capacity, and a hydrophobic backbone that is kept unaggregated by intra-chain repulsion. As a result, in solution PEI exhibits multiple buffering mechanisms, and polyelectrolyte states that shift between aggregated and free forms. We studied the interplay between the aggregation and protonation behavior of 2.5 kDa linear PEI by pH probing, vapor pressure osmometry, dynamic light scattering, and ninhydrin assay. Our results indicate that: At neutral pH, the PEI chains are associated and the addition of NaCl initially reduces and then increases the extent of association. The aggregate form is uncollapsed and co-exists with the free chains. PEI buffering occurs due to continuous or discontinuous charging between stalled states. Ninhydrin assay tracks the number of unprotonated amines in PEI. The size of PEI-DNA complexes is not significantly affected by the free vs. aggregated state of the PEI polymer. Despite its simple chemical structure, linear PEI displays intricate solution dynamics, which can be harnessed for environment-sensitive biomaterials and for overcoming current challenges with DNA delivery. PMID:27685846

  18. Ion pairing in aqueous lithium salt solutions with monovalent and divalent counter-anions.

    PubMed

    Pluhařová, Eva; Mason, Philip E; Jungwirth, Pavel

    2013-11-21

    Molecular dynamics simulations of concentrated aqueous solutions of LiCl and Li2SO4 were conducted in order to provide molecular insight into recent neutron scattering data. The structures predicted from the molecular dynamics simulations using standard nonpolarizable force fields provided a very poor fit to the experiment; therefore, refinement was needed. The electronic polarizability of the medium was effectively accounted for by implementing the electronic continuum correction, which practically means rescaling the ionic charges. Consistent with previous studies, we found that this approach in each case provided a significantly improved fit to the experimental data, which was further enhanced by slightly adjusting the radius of the lithium ion. The polarization effect was particularly pronounced in the Li2SO4 solution where the ions in the nonpolarizable simulations tended to cluster unphysically. With the above alterations, the employed force field displayed an excellent fit to the neutron scattering data and provided a useful interpretative framework for the experimental measurements. At the same time, the present study underlines the importance of solvent polarization effects in hydration of ions with high charge density.

  19. Photoemission spectra of aqueous solutions of salts from many-body perturbation theory

    NASA Astrophysics Data System (ADS)

    Gaiduk, Alex P.; Skone, Jonathan H.; Govoni, Marco; Galli, Giulia

    The computational design of electrode materials for energy conversion and storage processes requires an accurate description of the energy levels of the electrolyte and of electrolyte/electrode interfaces. Conventional density-functional approximations are in general not well suited for this task as they yield inaccurate orbital energies. Many-body perturbation theory (MBPT) predicts vertical ionization potentials and energy gaps in better agreement with experiments, providing the possibility for an accurate description of the electronic properties of electrolytes. We coupled ab initio molecular dynamics with MBPT calculations to investigate the photoemission spectra of a 1 M aqueous solution of NaCl. For the first time we were able to determine the absolute positions of the spectra peaks, with excellent agreement with experiments for both the solute and solvent peak positions. The best results were obtained using wavefunctions obtained from dielectric-dependent hybrid calculations as a starting point for MBPT. Work supported by DOE BES DE-SC0008938. Computer time provided by the Argonne Leadership Computing Facility through the INCITE program.

  20. Effects of isosmotic and hyperosmotic glycine solutions on the fluid balance in conscious sheep.

    PubMed

    Hahn, R; Hjelmqvist, H; Rundgren, M

    1989-01-01

    Glycine 0.55 g.kg-1 was given as an isosmotic (285 mosmol.kg-1) and a hyperosmotic (approx. 3,000 mosmol.kg-1) solution by intravenous infusion during 30 min to six euhydrated ewes. Urine and blood samples were collected, and the distribution of the administered water between the intra- and extracellular fluids (ICF and ECF) was calculated for up to 150 min after the infusions. Both solutions produced an osmotic diuresis with a marked increase of the urinary excretion of sodium, potassium, and amino acids. A paradoxical increase of the plasma vasopressin concentration occurred from the isosmotic but not from the hyperosmotic glycine solution. At the end of the follow-up period, the isosmotic glycine solution had resulted in hyperhydration of the ICF and the hyperosmotic solution in dehydration of the ICF, whereas with both fluids, the ECF resumed the same volume as before the experiments.

  1. Electrostatic Properties of Aqueous Salt Solution Interfaces: A Comparison of Polarizable and Non-Polarizable Ion Models

    PubMed Central

    Warren, G. Lee; Patel, Sandeep

    2014-01-01

    The effects of ion force field polarizability on the interfacial electrostatic properties of ~1 M aqueous solutions of NaCl, CsCl and NaI are investigated using molecular dynamics simulations employing both non-polarizable and Drude-polarizable ion sets. Differences in computed depth-dependent orientational distributions, “permanent” and induced dipole and quadrupole moment profiles, and interfacial potentials are obtained for both ion sets to further elucidate how ion polarizability affects interfacial electrostatic properties among the various salts relative to pure water. We observe that the orientations and induced dipoles of water molecules are more strongly perturbed in the presence of polarizable ions via a stronger ionic double layer effect arising from greater charge separation. Both anions and cations exhibit enhanced induced dipole moments and strong z alignment in the vicinity of the Gibbs dividing surface (GDS) with the magnitude of the anion induced dipoles being nearly an order of magnitude larger than those of the cations and directed into the vapor phase. Depth-dependent profiles for the trace and zz components of the water molecular quadrupole moment tensors reveal 40% larger quadrupole moments in the bulk phase relative to the vapor mimicking a similar observed 40% increase in the average water dipole moment. Across the GDS, the water molecular quadrupole moments increase non-monotonically (in contrast to the water dipoles) and exhibit a locally reduced contribution just below the surface due to both orientational and polarization effects. Computed interfacial potentials for the non-polarizable salts yield values 20 to 60 mV more positive than pure water and increase by an additional 30 to 100 mV when ion polarizability is included. A rigorous decomposition of the total interfacial potential into ion monopole, water and ion dipole, and water quadrupole components reveals that a very strong, positive ion monopole contribution is offset by

  2. Spectroscopic Investigation of the Formation of Radiolysis By-Products By 13/9 MeV Linear Accelerator of Electrons (LAE) in Salt Solutions

    SciTech Connect

    Paviet-Hartmann, P.; Dziewinski, J.; Hartmann, T.; Marczak, S.; Lu, N.; Walthall, M.; Rafalski, A.; Zagorski, Z. P.

    2002-02-26

    In the near-field chemistry of a salt repository, the radiolytically-induced redox reactions in concentrated saline solution are of particular importance because the radiolysis of saline solutions results in oxidizing chlorine-containing species, which may oxidize actinide species to higher oxidation states. If the brines are irradiated, the solutions containing radiolytic species such as hypochlorite, hypochlorous acid or hydrogen peroxide, their pH and Eh may be altered. The oxidation and complexation states of actinides, which might be present in the salt brine, will change thus influencing their speciation and consequently their mobility. Furthermore, radiolytically formed oxidizing species such as ClO- or H2O2 may enhance the corrosion of the canister material. Therefore, radiation effects on salt brines must be integrated into the database, which described the chemical processes near a disposal site. Investigations in that context usually focus on the radiation chemistry of solid NaCl however our focus is on the radiolytic products, which are formed when salt brines are irradiated by a 10 MeV linear accelerator of electrons (LAE). We attempt to quantify the irradiation-induced formation of typical radiolysis by-products such as the hypochlorite ion (OCl-) by using a 13/9 MeV LAE with doses between 120 KGy to 216 KGy while monitoring the pH of the brine solutions.

  3. Use of a liter-scale microbial desalination cell as a platform to study bioelectrochemical desalination with salt solution or artificial seawater.

    PubMed

    Jacobson, Kyle S; Drew, David M; He, Zhen

    2011-05-15

    Bioelectrochemical desalination is potentially advantageous because of bioenergy production and integrated wastewater treatment and desalination. In this work, the performance and energy benefits of a liter-scale upflow microbial desalination cell (UMDC) were evaluated. The UMDC desalinated both salt solution (NaCl) and artificial seawater, and the removal rate of total dissolved solid (TDS) increased with an increased hydraulic retention time, although TDS reduction in artificial seawater was lower than that in salt solution. Our analysis suggested that electricity generation was a predominant factor in removing TDS (more than 70%), and that other factors, like water osmosis and unknown processes, also contributed to TDS reduction. It was more favorable given the high energy efficiency, when treating salt solution, to operate the UMDC under the condition of high power output compared with that of high current generation because of the amount of energy production; while high current generation was more desired with seawater desalination because of lower salinity in the effluent. Under the condition of the high power output and the assumption of the UMDC as a predesalination in connection with a reversal osmosis (RO) system, the UMDC could produce electrical energy that might potentially account for 58.1% (salt solution) and 16.5% (artificial seawater) of the energy required by the downstream RO system. Our results demonstrated the great potential of bioelectrochemical desalination.

  4. Heat Transfer from Optically Excited Gold Nanostructures into Water, Sugar, and Salt Solutions

    NASA Astrophysics Data System (ADS)

    Green, Andrew J.

    coherence length associated with the liquid-liquid transition. The second topic will measure the change in heat dissipation with respect to solute adhesion onto the nanoheater. A small amount of aqueous solute molecules (1 solute molecule in 550 water molecules) dramatically increases the heat dissipation from a nanoparticle into the surrounding liquid. This result is consistent with a thermal conductance that is limited by an interface interaction where minority aqueous components significantly alter the surface properties and heat transport through the interface. The increase in heat dissipation can be used to make an extremely sensitive molecular detector that can be scaled to give single molecule detection without amplification or utilizing fluorescence labels.

  5. Studies on Nylon-66 membrane using aqueous solutions of potassium and lead nitrate salts as permeants

    NASA Astrophysics Data System (ADS)

    Kumar, Manoj; Ram, Bali

    2015-03-01

    Measurements on hydrodynamic and electro-osmotic permeability of water and aqueous solutions of KNO3 and Pb(NO3)2 in the concentration (C) range of 10 -4 10^{-4} M to 10 -3 10^{-3} M are made across the Nylon-66 membrane. The data obtained are used to ascertain the form of transport equation using the theory of non-equilibrium thermodynamics. Conductance of membrane equilibrated with water and aqueous solutions are measured and the data are used to estimate phenomenological coefficients. These phenomenological coefficients are used to determine the average pore radius, the average number of pores and the membrane constant. Zeta potentials are evaluated using electro-osmotic permeability and membrane-permeant conductance data to understand the electrical nature of the membrane-permeant interface. It is observed that hydrodynamic permeability and electro-osmotic permeability depend linearly on the applied pressure difference and the potential difference, respectively.