WorldWideScience

Sample records for solution guanidine hcl

  1. Solute's perspective on how trimethylamine oxide, urea, and guanidine hydrochloride affect water's hydrogen bonding ability.

    Science.gov (United States)

    Pazos, Ileana M; Gai, Feng

    2012-10-18

    While the thermodynamic effects of trimethylamine oxide (TMAO), urea, and guanidine hydrochloride (GdnHCl) on protein stability are well understood, the underlying mechanisms of action are less well characterized and, in some cases, even under debate. Herein, we employ the stretching vibration of two infrared (IR) reporters, i.e., nitrile (C≡N) and carbonyl (C═O), to directly probe how these cosolvents mediate the ability of water to form hydrogen bonds with the solute of interest, e.g., a peptide. Our results show that these three agents, despite having different effects on protein stability, all act to decrease the strength of the hydrogen bonds formed between water and the infrared probe. While the behavior of TMAO appears to be consistent with its protein-protecting ability, those of urea and GdnHCl are inconsistent with their role as protein denaturants. The latter is of particular interest as it provides strong evidence indicating that although urea and GdnHCl can perturb the hydrogen-bonding property of water their protein-denaturing ability does not arise from a simple indirect mechanism.

  2. Ion exchange in HCl, NH2OH x HCl and N2H4 x 2HCl solutions

    International Nuclear Information System (INIS)

    Tohyama, Itiro; Otozai, Kiyoteru

    1977-01-01

    Distribution coefficients for 73 elements have been determined by the batch method in HCl, hydroxylamine and hydrazine solutions using strongly acidic and strongly basic exchanger resins. In general, a similar behaviour was observed. In some cases, however, the kind of onium ion was of considerable influence. Hydroxylamine and hydrazine solutions are useful as a substitute for HCl in many separations, as they are easily handled and can rapidly be decomposed by nitric acid. (orig./RB) [de

  3. Physical and chemical stability of palonosetron HCl in 4 infusion solutions.

    Science.gov (United States)

    Trissel, Lawrence A; Xu, Quanyun A

    2004-10-01

    Palonosetron HCl is a selective 5-HT(3) receptor antagonist used for the prevention of chemotherapy-induced nausea and vomiting. Palonosetron HCl may be diluted in an infusion solution for administraton. Consequently, stability information is needed for palonosetron HCl admixed in common infusion solutions. To evaluate the physical and chemical stability of palonosetron HCl in concentrations of 5 and 30 microg/mL in dextrose 5% injection, NaCl 0.9% injection, dextrose 5% in NaCl 0.45% injection, and dextrose 5% in lactated Ringer's injection. Triplicate test samples of palonosetron HCl at each concentration in each diluent were tested. Samples were stored and evaluated at appropriate intervals for up to 48 hours at room temperature ( approximately 23 degrees C) and 14 days under refrigeration (4 degrees C). Physical stability was assessed using turbidimetric and particulate measurement, as well as visual inspection. Chemical stability was assessed by HPLC. All of the admixtures were initially clear and colorless when viewed in normal fluorescent room light and with a Tyndall beam. Measured turbidity and particulate content were low initially and remained low throughout the study. The drug concentration was unchanged in any of the samples at either temperature throughout the study. Palonosetron HCl is physically and chemically stable in all 4 common infusion solutions for at least 48 hours at room temperature and 14 days under refrigeration.

  4. The etching of InP in HCl solutions : a chemical mechanism

    NARCIS (Netherlands)

    Notten, P.H.L.

    1984-01-01

    The etch rate of InP in solutions of high HCl concentration was shown to be independent of the applied potential ina wide potential range negative with respect to the flatband value. Dissolution of the solid led to the formation of PH3.The etch rate, which was not mass-transport controlled, was

  5. Formulation and stability of an extemporaneously compounded oral solution of chlorpromazine HCl.

    Science.gov (United States)

    Prohotsky, Daniel L; Juba, Katherine M; Zhao, Fang

    2014-12-01

    Chlorpromazine is a phenothiazine antipsychotic which is often used in hospice and palliative care to treat hiccups, delirium, and nausea. With the discontinuation of the commercial oral solution concentrate, there is a need to prepare this product by extemporaneous compounding. This study was initiated to identify an easy-to-prepare formulation for the compounding pharmacist. A stability study was also conducted to select the proper storage conditions and establish the beyond-use date. Chlorpromazine HCl powder and the Ora-Sweet® syrup vehicle were used to prepare the 100 mg/mL solution. Once the feasibility was established, a batch of the solution was prepared and packaged in amber plastic prescription bottles for a stability study. These samples were stored at refrigeration (2-8°C) or room temperature (20-25°C) for up to 3 months. At each monthly time point, the samples were evaluated by visual inspection, pH measurement, and high performance liquid chromatography (HPLC). A separate forced stability study was conducted to confirm that the HPLC method was stability indicating. A clear and colorless solution of 100 mg/mL chlorpromazine HCl was obtained by dissolving the drug powder in Ora-Sweet® with moderate agitation. The stability study results indicated that this solution product remained unchanged in visual appearance or pH at both refrigeration and room temperature for up to 3 months. The HPLC results also confirmed that all stability samples retained 93.6-101.4% of initial drug concentration. Chlorpromazine HCl solution 100 mg/mL can be compounded extemporaneously by dissolving chlorpromazine HCl drug powder in Ora-Sweet®. The resulting product is stable for at least three months in amber plastic prescription bottles stored at either refrigeration or room temperature.

  6. Benzimidazole and its derivatives as corrosion inhibitors for mild steel in 1M HCl solution

    International Nuclear Information System (INIS)

    Aljourani, J.; Raeissi, K.; Golozar, M.A.

    2009-01-01

    In this paper, the inhibition ability of benzimidazole and its derivatives against the corrosion of mild steel in 1M HCl solution was studied. The change of impedance parameters observed by variation of inhibitors concentration within the range of 50-250 ppm was an indication of their adsorption. The thermodynamic adsorption parameters proposed that these inhibitors retard both cathodic and anodic processes through physical adsorption and blocking the active corrosion sites. The adsorption of these compounds obeyed the Langmuir's adsorption isotherm. The inhibition efficiency was increased with inhibitor concentration in the order of 2-mercaptobenzimidazole > 2-methylbenzimidazole > benzimidazole, which is in accordance with the variation of apparent activation energy of corrosion.

  7. Porous hydrogel of wool keratin prepared by a novel method: An extraction with guanidine/2-mercaptoethanol solution followed by a dialysis

    Energy Technology Data Exchange (ETDEWEB)

    Ozaki, Yuki; Takagi, Yusuke; Mori, Hideki; Hara, Masayuki, E-mail: hara@b.s.osakafu-u.ac.jp

    2014-09-01

    In this study, we show a novel simple method to prepare a sponge-like porous keratin hydrogel through the extraction of wool keratin in a solution containing guanidine hydrochloride and 2-mercaptoethanol followed by dialysis for both aggregation of keratin and recrosslink. The gel had a highly porous structure and a fast-swelling property in rehydration after freeze-drying. It had also high mechanical strength both in the tensile test and the measurement of dynamic viscoelasticity. Three types of animal cells, PC12 cells, HOS cells and murine embryonic fibroblasts, well attached and grew on the surface of the porous hydrogel. - Graphical abstract: We show a novel simple method to prepare a sponge-like porous keratin hydrogel (A, B) through the extraction of wool keratin in a solution containing guanidine hydrochloride and 2-mercaptoethanol followed by dialysis for both aggregation of keratin and recrosslink. The gel had a highly porous structure (B) and a fast-swelling property in rehydration after freeze-drying. It had also high mechanical strength both in the tensile test (C) and the measurement of dynamic viscoelasticity (D). Three types of animal cells, PC12 cells (E), HOS cells (F) and murine embryonic fibroblasts (MEFs) (G), well attached and grew on the surface of the porous hydrogel. - Highlights: • We prepared a sponge-like porous keratin hydrogel by a novel method. • We used guanidine with 2-mercaptoethanol to extract keratin from wool fiber. • Extracted keratin was recrosslinked to form a porous keratin hydrogel in dialysis. • The keratin hydrogel had a high mechanical strength. • Three types of cells attached on the keratin hydrogel proliferated well.

  8. Porous hydrogel of wool keratin prepared by a novel method: An extraction with guanidine/2-mercaptoethanol solution followed by a dialysis

    International Nuclear Information System (INIS)

    Ozaki, Yuki; Takagi, Yusuke; Mori, Hideki; Hara, Masayuki

    2014-01-01

    In this study, we show a novel simple method to prepare a sponge-like porous keratin hydrogel through the extraction of wool keratin in a solution containing guanidine hydrochloride and 2-mercaptoethanol followed by dialysis for both aggregation of keratin and recrosslink. The gel had a highly porous structure and a fast-swelling property in rehydration after freeze-drying. It had also high mechanical strength both in the tensile test and the measurement of dynamic viscoelasticity. Three types of animal cells, PC12 cells, HOS cells and murine embryonic fibroblasts, well attached and grew on the surface of the porous hydrogel. - Graphical abstract: We show a novel simple method to prepare a sponge-like porous keratin hydrogel (A, B) through the extraction of wool keratin in a solution containing guanidine hydrochloride and 2-mercaptoethanol followed by dialysis for both aggregation of keratin and recrosslink. The gel had a highly porous structure (B) and a fast-swelling property in rehydration after freeze-drying. It had also high mechanical strength both in the tensile test (C) and the measurement of dynamic viscoelasticity (D). Three types of animal cells, PC12 cells (E), HOS cells (F) and murine embryonic fibroblasts (MEFs) (G), well attached and grew on the surface of the porous hydrogel. - Highlights: • We prepared a sponge-like porous keratin hydrogel by a novel method. • We used guanidine with 2-mercaptoethanol to extract keratin from wool fiber. • Extracted keratin was recrosslinked to form a porous keratin hydrogel in dialysis. • The keratin hydrogel had a high mechanical strength. • Three types of cells attached on the keratin hydrogel proliferated well

  9. On the impedance of galvanic cells XXV. The double-layer capacitance of the dropping mercury electrode in 1 M HCl, 7.5 M HCl and 5.2 M HClO4 and the kinetic parameters of the hydrogen electrode reaction as a function of temperature in these solutions

    NARCIS (Netherlands)

    Dekker, B.G.; Sluyters-Rehbach, M.; Sluyters, J.H.

    The impedance of the dropping mercury electrode in aqueous solutions in 1 M HCl, 7.5 M HCl and 5.2 M HClO4, saturated with hydrogen at one atmosphere was measured at temperatures between −39° and +72° both in and outside the potential region where the electrode reaction, e+H+ H2,

  10. Densities of L-Glutamic Acid HCl Drug in Aqueous NaCl and KCl Solutions at Different Temperatures

    Science.gov (United States)

    Ryshetti, Suresh; Raghuram, Noothi; Rani, Emmadi Jayanthi; Tangeda, Savitha Jyostna

    2016-04-01

    Densities (ρ ) of (0.01 to 0.07) {mol}{\\cdot } {kg}^{-1} L-Glutamic acid HCl (L-HCl) drug in water, and in aqueous NaCl and KCl (0.5 and 1.0) {mol}{\\cdot } {kg}^{-1} solutions have been reported as a function of temperature at T = (298.15, 303.15, 308.15, and 313.15) K and atmospheric pressure. The accurate density (ρ ) values are used to estimate the various parameters such as the apparent molar volume (V_{2,{\\upphi }}), the partial molar volume (V2^{∞}), the isobaric thermal expansion coefficient (α 2), the partial molar expansion (E2^{∞}), and Hepler's constant (partial 2V2^{∞}/partial T2)P. The Cosphere overlap model is used to understand the solute-solvent interactions in a ternary mixture (L-HCl drug + NaCl or KCl + water). Hepler's constant (partial 2V2^{∞}/partial T2)_P is utilized to interpret the structure-making or -breaking ability of L-HCl drug in aqueous NaCl and KCl solutions, and the results are inferred that L-HCl drug acts as a structure maker, i.e., kosmotrope in aqueous NaCl solutions and performs as a structure breaker, i.e., chaotrope in aqueous KCl solutions.

  11. Study on Corrosion Inhibition Efficiency of Stem Alkaloid Extract of Different Varieties of Holy Basil on Aluminium in HCl Solution

    Energy Technology Data Exchange (ETDEWEB)

    Kumpawat, Nutan; Chaturvedi, Alok; Upadhyay, R. K. [Synthetic and Surface Science Laboratory, Ajmer (India)

    2012-08-15

    Corrosion inhibition efficiencies of holy basil on Al in HCl solution were studied by weight loss and thermometric methods in presence and in absence of stem extract of three different varieties of holy basil viz. ocimum basilicum (E{sub B}), ocimum canum (E{sub C}) and ocimum sanctum (E{sub S}). Inhibition efficiency increases with the increasing concentration of stem extract and decreases with increases in acid strength. Results show that all varieties under study are good corrosion inhibitors, among which, E{sub B} is most effective. Maximum inhibition efficiency was found 97.09% in 0.5N HCl solution with 0.6% stem extract. The Langmuir adsorption isotherm indicates that surface coverage also increases with increasing in the concentration of extract of stem in HCl solution.

  12. Study on Corrosion Inhibition Efficiency of Stem Alkaloid Extract of Different Varieties of Holy Basil on Aluminium in HCl Solution

    International Nuclear Information System (INIS)

    Kumpawat, Nutan; Chaturvedi, Alok; Upadhyay, R. K.

    2012-01-01

    Corrosion inhibition efficiencies of holy basil on Al in HCl solution were studied by weight loss and thermometric methods in presence and in absence of stem extract of three different varieties of holy basil viz. ocimum basilicum (E B ), ocimum canum (E C ) and ocimum sanctum (E S ). Inhibition efficiency increases with the increasing concentration of stem extract and decreases with increases in acid strength. Results show that all varieties under study are good corrosion inhibitors, among which, E B is most effective. Maximum inhibition efficiency was found 97.09% in 0.5N HCl solution with 0.6% stem extract. The Langmuir adsorption isotherm indicates that surface coverage also increases with increasing in the concentration of extract of stem in HCl solution

  13. The electrochemical corrosion of bulk nanocrystalline ingot iron in HCl solutions with different concentrations

    International Nuclear Information System (INIS)

    Wang, S.G.; Sun, M.; Cheng, P.C.; Long, K.

    2011-01-01

    Highlights: → The corrosion resistance of BNII was enhanced in comparison with CPII in 0.1-0.4 mol L -1 solution. → The function work of BNII is 0.47 eV larger that of CPII. → The energy state density of 4s electrons of BNII is 13.73% less than that of CPII. → BNII corrosion resistance was enhanced due to its larger work function and less 4s electrons weight. → The specific adsorption of Cl - on BNII was weaker than that of CPII due to its larger function work. - Abstract: We studied the corrosion properties of bulk nanocrystalline ingot iron (BNII) and conventional polycrystalline ingot iron (CPII) in HCl solutions from 0.1 mol L -1 to 0.4 mol L -1 at room temperature. The corrosion resistance of BNII was enhanced in comparison with CPII. We investigated the surface energy state densities of BNII and CPII with ultra-violet photoelectron spectroscopy. The energy state density of BNII 4s electrons was 13.73% less than that of CPII. The function work of BNII was 0.47 eV larger that of CPII. The corrosion resistance of BNII was enhanced in comparison with CPII due to its less energy state density of 4s electrons, larger work function and weaker Cl - specific adsorption.

  14. A study of the inhibition of iron corrosion in HCl solutions by some amino acids

    International Nuclear Information System (INIS)

    Amin, Mohammed A.; Khaled, K.F.; Mohsen, Q.; Arida, H.A.

    2010-01-01

    The performance of three selected amino acids, namely alanine (Ala), cysteine (Cys) and S-methyl cysteine (S-MCys) as safe corrosion inhibitors for iron in aerated stagnant 1.0 M HCl solutions was evaluated by Tafel polarization and impedance measurements. Results indicate that Ala acts mainly as a cathodic inhibitor, while Cys and S-MCys function as mixed-type inhibitors. Cys, which contains a mercapto group in its molecular structure, was the most effective among the inhibitors tested, while Ala was less effective than S-MCys. The low inhibition efficiency recorded for S-MCys compared with that of Cys was attributed to steric effects caused by the substituent methyl on the mercapto group. Electrochemical frequency modulation (EFM) technique and inductively coupled plasma atomic emission spectrometry (ICP-AES), were also applied to make accurate determination of corrosion rates. Validation of the Tafel extrapolation method for measuring corrosion rates was tested. Rates of corrosion rates (in μm y -1 ) obtained from Tafel extrapolation method are in good agreement with those measured using EFM and ICP methods. Some theoretical studies, including molecular dynamics (MD) and density functional theory (DFT), were also employed to establish the correlation between the structure (molecular and electronic) of the three tested inhibitors and the inhibition efficiency. Adsorption via hydrogen bonding was discussed here based on some theoretical studies. Experimental and theoretical results were in good agreement.

  15. Calcium-induced stabilization of -amylase against guanidine ...

    African Journals Online (AJOL)

    Guanidine hydrochloride (GdnHCl) denaturation of native and Ca- depleted Bacillus licheniformis α-amylase (BLA) was investigated both in the absence and presence of 2 mM calcium chloride (CaCl2) using circular dichroism, fluorescence spectroscopy and biological activity. In both states (Cadepleted and native form), ...

  16. Corrosion initiation of stainless steel in HCl solution studied using electrochemical noise and in-situ atomic force microscope

    International Nuclear Information System (INIS)

    Li Yan; Hu Ronggang; Wang Jingrun; Huang Yongxia; Lin Changjian

    2009-01-01

    An in-situ atomic force microscope (AFM), optical microscope and electrochemical noise (ECN) techniques were applied to the investigation of corrosion initiations in an early stage of 1Cr18Ni9Ti stainless steel immersed in 0.5 M HCl solution. The electrochemical current noise data has been analyzed using discrete wavelet transform (DWT). For the first time, the origin of wavelet coefficients is discussed based on the correlation between the evolution of the energy distribution plot (EDP) of wavelet coefficients and topographic changes. It is found that the occurrence of initiation of metastable pitting at susceptive sites is resulted from the reductive breakdown of passive film of stainless steel in the diluted HCL solution. The coefficients d 4 -d 6 are originated from metastable pitting, d 7 represents the formation and growth of stable pitting while d 8 corresponds to the general corrosion.

  17. Citropin 1.1 Trifluoroacetate to Chloride Counter-Ion Exchange in HCl-Saturated Organic Solutions: An Alternative Approach.

    Science.gov (United States)

    Sikora, Karol; Neubauer, Damian; Jaśkiewicz, Maciej; Kamysz, Wojciech

    2018-01-01

    In view of the increasing interest in peptides in various market sectors, a stronger emphasis on topics related to their production has been seen. Fmoc-based solid phase peptide synthesis, although being fast and efficient, provides final products with significant amounts of trifluoroacetate ions in the form of either a counter-ion or an unbound impurity. Because of the proven toxicity towards cells and peptide activity inhibition, ion exchange to more biocompatible one is purposeful. Additionally, as most of the currently used counter-ion exchange techniques are time-consuming and burdened by peptide yield reduction risk, development of a new approach is still a sensible solution. In this study, we examined the potential of peptide counter-ion exchange using non-aqueous organic solvents saturated with HCl. Counter-ion exchange of a model peptide, citropin 1.1 (GLFDVIKKVASVIGGL-NH 2 ), for each solvent was conducted through incubation with subsequent evaporation under reduced pressure, dissolution in water and lyophilization. Each exchange was performed four times and compared to a reference method-lyophilization of the peptide from an 0.1 M HCl solution. The results showed superior counter-ion exchange efficiency for most of the organic solutions in relation to the reference method. Moreover, HCl-saturated acetonitrile and tert -butanol provided a satisfying exchange level after just one repetition. Thus, those two organic solvents can be potentially introduced into routine peptide counter-ion exchange.

  18. First results on the sorption behaviour of Rutherfordium from HCl/HF containing aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Schumann, D.; Nitsche, H. [Technische Univ. Dresden (Germany); Taut, S. [Forschungszentrum Rossendorf e.V. (FZR), Dresden (Germany); Jost, D.T.; Gaeggeler, H.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Yakushev, A.B.; Buklanov, G.V.; Domanov, V.P.; Lien Din Thi [Joint Inst. for Nuclear Research, Dubna (Russian Federation); Kubica, B.; Misiak, R.; Szeglowski, Z. [NINP Cracow (Poland)

    1997-09-01

    Rutherfordium shows strong sorption on the cation exchanger DOWEX 50x8 at a concentration of 0.1 M HCl/10{sup -2} M HF. This shows that Rf behaves under these conditions differently from Hf and Zr and more like Th under these conditions. (author) 1 fig., 5 refs.

  19. The nonaqueous inhibition of Fe-Co-B-Si amorphous electrodes: An a.c. impedance study in HCl solutions

    International Nuclear Information System (INIS)

    Habib, K.; Abdullah, A.

    1995-01-01

    An electrochemical study on Fe-Co-B-Si amorphous electrodes has been conducted. The study was focused on determining the electrochemical impedance spectroscopy (EIS) of four different alloys of Fe-Co-B-Si in various HCl acid solutions. The A.C. impedance and the capacitance of Fe-Co-B-Si, Co-Fe-Ni-B-Si, Co-Fe-Mn-B-Si, and Co-Fe-Ni-Mo-B-Si alloys were obtained in 25, 50, 75 and 100% of HCl acid at room temperature. Electrochemical parameters, i.e., impedance, were found to vary depending on additions of the Ni, Mn, Ni-Mo to Fe-Co-B-Si alloy, the acid concentration, and the nanoscopic surface roughness of the electrodes. Consequently, a correlation between the obtained data is established

  20. Density, speed of sound, viscosity and refractive index properties of aqueous solutions of vitamins B1.HCl and B6.HCl at temperatures (278.15, 288.15, and 298.15) K

    International Nuclear Information System (INIS)

    Dhondge, Sudhakar S.; Deshmukh, Dinesh W.; Paliwal, Lalitmohan J.

    2013-01-01

    Highlights: ► Study of aqueous solutions of vitamins B 1 .HCl and B 6 .HCl at different temperatures has been presented. ► These are important vitamins. ► Different interactions among solute and solvents have been investigated. ► The results are interpreted in terms of water structure making and breaking effects due to cations. -- Abstract: The experimental values of density (ρ), speed of sound (u), absolute viscosity (η) and refractive index (n D ) properties are reported for aqueous solutions of thiamine hydrochloride (vitamin B 1 .HCl) and pyridoxine hydrochloride (vitamin B 6 .HCl) within the concentration range (0.01 to 0.55) mol ⋅ kg −1 at three different temperatures, viz. T/K = 278.15, 288.15, and 298.15. Using experimental data, different derived parameters such as the apparent molar volume of solute (ϕ V ), isentropic compressibility of solution (β S ), apparent molar isentropic compressibility of solute (ϕ KS ) and relative viscosity of solution (η r ) have been computed. The limiting values of apparent molar volume (ϕ V 0 ) and apparent molar isentropic compressibility (ϕ KS 0 ) have been obtained. The limiting apparent molar expansivity (ϕ E 0 ) of solute, coefficient of thermal expansion (α ∗ ) and hydration numbers (n h ) of above vitamins in the aqueous medium have also been estimated. The experimental values of relative viscosity are used to calculate the Jones–Dole equation viscosity A and B coefficients for the hydrochlorides. The temperature coefficients of B i.e. (dB/dT) for these solutes have been used to study water structure making and breaking effects due to cations. Further, a discussion is made on the basis of solute–solute and solute–solvent interactions

  1. Corrosion Inhibition of Carbon Steel in HCl Solution by Some Plant Extracts

    Directory of Open Access Journals (Sweden)

    Ambrish Singh

    2012-01-01

    Full Text Available The strict environmental legislations and increasing ecological awareness among scientists have led to the development of “green” alternatives to mitigate corrosion. In the present work, literature on green corrosion inhibitors has been reviewed, and the salient features of our work on green corrosion inhibitors have been highlighted. Among the studied leaves, extract Andrographis paniculata showed better inhibition performance (98% than the other leaves extract. Strychnos nuxvomica showed better inhibition (98% than the other seed extracts. Moringa oleifera is reflected as a good corrosion inhibitor of mild steel in 1 M HCl with 98% inhibition efficiency among the studied fruits extract. Bacopa monnieri showed its maximum inhibition performance to be 95% at 600 ppm among the investigated stem extracts. All the reported plant extracts were found to inhibit the corrosion of mild steel in acid media.

  2. Application of a cosmetic additive as an eco-friendly inhibitor for mild steel corrosion in HCl solution.

    Science.gov (United States)

    Liao, Liu Li; Mo, Shi; Lei, Jing Lei; Luo, Hong Qun; Li, Nian Bing

    2016-07-15

    The use of the cosmetic ingredient cocamidopropylamine oxide (CAO) to inhibit the corrosion of steel in 0.5mol/LHCl is investigated. Electrochemical and weight loss methods were used to evaluate the inhibiting effect of CAO and the influences of inhibitor concentration and temperature were determined. It was found that CAO acted as a mix-type inhibitor and was adsorbed chemically onto the steel in HCl solution, and the maximum inhibition efficiency was found at critical micelle concentration (CMC) of CAO in tested corrosive media. Moreover, it was speculated that relationships of the two adsorption sites of the inhibitor and steel surface were different. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Opuntia ficus-indica Extract as Green Corrosion Inhibitor for Carbon Steel in 1 M HCl Solution

    Directory of Open Access Journals (Sweden)

    J. P. Flores-De los Ríos

    2015-01-01

    Full Text Available The effect of Opuntia ficus-indica (Nopal as green corrosion inhibitor for carbon steel in 1 M HCl solution has been investigated by using weight loss tests, potentiodynamic polarization curves, and electrochemical impedance spectroscopy measurements. Also, scanning electron microscopy (SEM and Fourier transform infrared spectroscopy (FT-IR analysis were performed. The inhibitor concentrations used ranged from 0 to 300 ppm at 25, 40, and 60°C. Results indicated the inhibition efficiency increases with increasing extract concentration and decreases with the temperature, and the inhibitor acted as a cathodic-type inhibitor which is physically absorbed onto the steel surface. In fact, the adsorption of the inhibitor on the steel surface follows the Langmuir adsorption isotherm, indicating monolayer adsorption. The presence of heteroatoms such as C, N, and O and OH groups were responsible for the corrosion inhibition.

  4. Induction of cytoplasmic petite in yeast by guanidine hydrochloride

    International Nuclear Information System (INIS)

    Villa, L.L.; Juliani, M.H.

    1980-01-01

    We have studied the induction of p - mutants by guanidine hydrochloride (GuHCL) in combination with other known inducers; ethidium bromide (EB), berenil and ultraviolet light. Competition was observed when cells were simultaneously treated with optimal concentrations of EB and GuHCL; on the other hand, treatment of cells with EB in the presence of non-inducing concentrations of GuHCL resulted in the stimulation of p - induction by EB. Furthermore, using a strain which upon treatment with high EB concentrations shows recovery of respiratory competence, the presence of GuHCL did not interfere either with the early phase of induction or with the recovery phase, but it did interfere in a competitive fashion with the final irreversible phase of EB induction. In the case of berenil, a synergistic effect was seen when cells were pretreated with GuHCL. A synergistic induction was also observed when cells were submitted to UV prior to GuHCL treatment. These results suggest that GuHCL, EB and berenil act via some common step in their p - induction pathways. Moreover, GuHCL may somehow be decreasing the efficiency of dark repair of ultraviolet lesions on mitochondrial DNA. (orig.)

  5. Inhibition by Ginkgo leaves extract of the corrosion of steel in HCl and H{sub 2}SO{sub 4} solutions

    Energy Technology Data Exchange (ETDEWEB)

    Deng Shuduan, E-mail: dengshuduan@163.com [Faculty of Materials Engineering, Southwest Forestry University, Kunming 650224 (China); Li Xianghong [Faculty of Science, Southwest Forestry University, Kunming 650224 (China)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Ginkgo leaves extract (GLE) acts as a good inhibitor for steel in HCl and H{sub 2}SO{sub 4} media. Black-Right-Pointing-Pointer The inhibition efficiency follows the order: HCl > H{sub 2}SO{sub 4}. Black-Right-Pointing-Pointer The adsorption of GLE on steel surface obeys Langmuir adsorption isotherm. Black-Right-Pointing-Pointer GLE behaves as a mixed-type inhibitor in 1.0 M HCl, while cathodic inhibitor in 0.5 M H{sub 2}SO{sub 4}. - Abstract: The inhibition effect of Ginkgo leaves extract (GLE) on the corrosion of cold rolled steel (CRS) in 1.0-5.0 M HCl and 0.5-2.5 M H{sub 2}SO{sub 4} solutions was investigated for the first time by weight loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) methods. The results show that GLE is a good inhibitor, and exhibits more efficient in 1.0 M HCl than 0.5 M H{sub 2}SO{sub 4}. The adsorption of GLE on CRS surface obeys Langmuir adsorption isotherm. GLE acts as a mixed-type inhibitor in 1.0 M HCl, while a cathodic inhibitor in 0.5 M H{sub 2}SO{sub 4}.

  6. Mechanochemical synthesis of thioureas, ureas and guanidines

    Directory of Open Access Journals (Sweden)

    Vjekoslav Štrukil

    2017-09-01

    Full Text Available In this review, the recent progress in the synthesis of ureas, thioureas and guanidines by solid-state mechanochemical ball milling is highlighted. While the literature is abundant on their preparation in conventional solution environment, it was not until the advent of solvent-free manual grinding using a mortar and pestle and automated ball milling that new synthetic opportunities have opened. The mechanochemical approach not only has enabled the quantitative synthesis of (thioureas and guanidines without using bulk solvents and the generation of byproducts, but it has also been established as a means to develop "click-type" chemistry for these classes of compounds and the concept of small molecule desymmetrization. Moreover, mechanochemistry has been demonstrated as an effective tool in reaction discovery, with emphasis on the reactivity differences in solution and in the solid state. These three classes of organic compounds share some structural features which are reflected in their physical and chemical properties, important for application as organocatalysts and sensors. On the other hand, the specific and unique nature of each of these functionalities render (thioureas and guanidines as the key constituents of pharmaceuticals and other biologically active compounds.

  7. A comparative study on the aggregating effects of guanidine thiocyanate, guanidine hydrochloride and urea on lysozyme aggregation

    Energy Technology Data Exchange (ETDEWEB)

    Emadi, Saeed, E-mail: emadi@iasbs.ac.ir; Behzadi, Maliheh

    2014-08-08

    Highlights: • Lysozyme aggregated in guanidine thiocyanate (1.0 and 2.0 M). • Lysozyme aggregated in guanidine hydrochloride (4 and 5 M). • Lysozyme did not aggregated at any concentration (0.5–5 M) of urea. • Unfolding pathway is more important than unfolding per se in aggregation. - Abstract: Protein aggregation and its subsequent deposition in different tissues culminate in a diverse range of diseases collectively known as amyloidoses. Aggregation of hen or human lysozyme depends on certain conditions, namely acidic pH or the presence of additives. In the present study, the effects on the aggregation of hen egg-white lysozyme via incubation in concentrated solutions of three different chaotropic agents namely guanidine thiocyanate, guanidine hydrochloride and urea were investigated. Here we used three different methods for the detection of the aggregates, thioflavin T fluorescence, circular dichroism spectroscopy and atomic force microscopy. Our results showed that upon incubation with different concentrations (0.5, 1.0, 2.0, 3.0, 4.0, 5.0 M) of the chemical denaturants, lysozyme was aggregated at low concentrations of guanidine thiocyanate (1.0 and 2.0 M) and at high concentrations of guanidine hydrochloride (4 and 5 M), although no fibril formation was detected. In the case of urea, no aggregation was observed at any concentration.

  8. Theoretical predictions of hydrolysis and complex formation of group-4 elements Zr, Hf and Rf in HF and HCl solutions

    International Nuclear Information System (INIS)

    Pershina, V.; Trubert, D.; Le Naour, C.; Kratz, J.V.

    2002-01-01

    Fully relativistic molecular density-functional calculations of the electronic structures of hydrated, hydrolyzed and fluoride/chloride complexes have been performed for group-4 elements Zr, Hf, and element 104, Rf. Using the electronic density distribution data, relative values of the free energy change for hydrolysis and complex formation reactions were defined. The results show the following trend for the first hydrolysis step of the cationic species: Zr>Hf>Rf in agreement with experiments. For the complex formation in HF solutions, the trend to a decrease from Zr to Hf is continued with Rf, provided no hydrolysis takes place. At pH>0, further fluorination of hydrolyzed species or fluoro-complexes has an inversed trend in the group Rf≥Zr>Hf, with the difference between the elements being very small. For the complex formation in HCl solutions, the trend is continued with Rf, so that Zr>Hf>Rf independently of pH. A decisive energetic factor in hydrolysis or complex formation processes proved to be a predominant electrostatic metal-ligand interaction. Trends in the K d (distribution coefficient) values for the group-4 elements are expected to follow those of the complex formation

  9. Sorption behaviour of W, Hf, Lu, U, and Th on ion exchangers from HCl/H2O2 solutions. Model experiments for chemical studies of seaborgium (Sg)

    International Nuclear Information System (INIS)

    Schumann, D.; Andrassy, M.; Nitsche, H.; Misiak, R.; Schaedel, M.; Bruechle, W.; Schausten, B.; Kratz, J.V.

    1997-08-01

    In model experiments with W, Hf, Th, and U radionuclides, a chemical system was developed for the separation of seaborgium from element 104 and heavy actinides, i.e., cation exchange on DOWEX 50 x 8 from solutions containing 0.1-1.0 M HCl and 0.5-2.0 vol.% H 2 O 2 . The system should be suitable for fast on-line experiments if seaborgium exibits a non-uranium-like behaviour. Adding hydrogen peroxide to mixed HCl/HF solutions suppresses the partial sorption of W and, presumably seaborgium, on the cation exchanger. This way, the elution volume can be minimized. Prospects for anion exchange separations of group 6 from 4 elements are also briefly discussed. (orig.)

  10. Corrosion inhibition of aluminum with a series of aniline monomeric surfactants and their analog polymers in 0.5 M HCl solution

    Directory of Open Access Journals (Sweden)

    M.M. El-Deeb

    2015-07-01

    Full Text Available The inhibition effect of 3-(12-sodiumsulfonate dodecyloxy aniline monomeric surfactant (MC12 and its analog polymer Poly 3-(dodecyloxy sulfonic acid aniline (PC12 on the corrosion of aluminum in 0.5 M HCl solution was investigated using weight loss and potentiodynamic polarization techniques. The presence of these two compounds in 0.5 M HCl inhibits the corrosion of aluminum without modifying the mechanism of corrosion process. It was found that these inhibitors act as mixed-type inhibitors with anodic predominance as well as the inhibition efficiency increases with increasing inhibitor concentration, but decreases with raising temperature. Langmuir and Frumkin adsorption isotherms fit well with the experimental data. Thermodynamic functions for both dissolution and adsorption processes were determined. The obtained results from weight loss and potentiodynamic polarization techniques are in good agreement with contact angle measurements.

  11. Alkaloids extract of Retama monosperma (L.) Boiss. seeds used as novel eco-friendly inhibitor for carbon steel corrosion in 1 M HCl solution: Electrochemical and surface studies

    Energy Technology Data Exchange (ETDEWEB)

    El Hamdani, Naoual; Fdil, Rabiaa [Laboratoire de Chimie Bioorganique, Faculté des Sciences, Université Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco); Tourabi, Mustapha [Laboratoire de Catalyse et de Corrosion des Matériaux (LCCM), Faculté des Sciences, Université Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco); Jama, Charafeddine [UMET-PSI, CNRS UMR 8207, ENSCL, Université Lille 1, CS 90108, F-59652 Villeneuve d’Ascq Cedex (France); Bentiss, Fouad, E-mail: fbentiss@enscl.fr [Laboratoire de Catalyse et de Corrosion des Matériaux (LCCM), Faculté des Sciences, Université Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco); UMET-PSI, CNRS UMR 8207, ENSCL, Université Lille 1, CS 90108, F-59652 Villeneuve d’Ascq Cedex (France)

    2015-12-01

    Graphical abstract: - Highlights: • AERS is good eco-friendly corrosion inhibitor for carbon steel in 1 M HCl. • AERS acts as mixed-type inhibitor in 1 M HCl medium. • AERS adsorption is well described by Langmuir isotherm. • Surface analyses were used to explain the AERS mechanism of carbon steel corrosion inhibition. - Abstract: Current research efforts now focus on the development of non-toxic, inexpensive and environmentally friendly corrosion inhibitors as alternatives to different organic and non-organic compounds. In this field, alkaloids extract of Retama monosperma (L.) Boiss. seeds (AERS) was tested for the first time as corrosion inhibitor for carbon steel in 1 M HCl medium using electrochemical and surface characterization techniques. The obtained results showed that this plant extract's acts as an efficient corrosion inhibitor for carbon steel in 1 M HCl and an inhibition efficiency of 94.4% was reached with 400 mg/L of AERS at 30 °C. Ac impedance experimental data revealed a frequency distribution of the capacitance, simulated as constant phase element. Impedance results demonstrated that the addition of the AERS in the corrosive solution decreases the charge capacitance and simultaneously increases the function of the charge/discharge of the interface, facilitating the formation of an adsorbed layer over the steel surface. Polarization curves indicated that AERS is a mixed inhibitor. Adsorption of such alkaloid extract on the steel surface obeyed to the Langmuir adsorption isotherm. X-ray photoelectron spectroscopy (XPS) showed that the inhibition of steel corrosion in normal hydrochloric solution by AERS is mainly controlled by a physisorption process and the inhibitive layer is composed of an iron oxide/hydroxide mixture where AERS molecules are incorporated.

  12. Failure Analysis of the HCl Column Inter Cooler Cause, Effect, Results and Economical Solution for Severe Media Case Study

    International Nuclear Information System (INIS)

    Zaher, A.

    2004-01-01

    The Egyptian Petrochemicals Co. (EPC) is located at Alexandria- Egypt, it is considered as one of the most important plants in the middle east, it consists of the following plants: PVC plant with possible expansions, VCM Plant, Cl 2 Chlorine and NaOH Caustic Soda Plant, PVC Compounding plant, Power Plant, and Utility plant. (EPC) had been established since 1987 for the production of the products (PVC Resin, PVC Compounding, Chlorine Liquid, Caustic Soda Flaks, 50% Liquid Concentration, HCl Acid 30% Concentration, and sodium hypochlorite 12%) these materials are supplied to the local market, and Exported to the European and Arabic Countries

  13. Synergism between rare earth cerium(IV) ion and vanillin on the corrosion of cold rolled steel in 1.0 M HCl solution

    Energy Technology Data Exchange (ETDEWEB)

    Li Xianghong [Department of Fundamental Courses, Southwest Forestry University, Kunming 650224 (China)], E-mail: xianghong-li@163.com; Deng Shuduan [Department of Wood Science and Technology, Southwest Forestry University, Kunming 650224 (China); Fu Hui [Department of Fundamental Courses, Southwest Forestry University, Kunming 650224 (China); Mu Guannan [Department of Chemistry, Yunnan University, Kunming 650091 (China)

    2008-12-15

    The synergism between rare earth cerium(IV) ion and vanillin on the corrosion of cold rolled steel (CRS) in 1.0 M HCl solution was first investigated by weight loss, potentiodynamic polarization, ultraviolet and visible spectrophotometer (UV-vis), X-ray photoelectron spectroscopy (XPS) and atomic force microscope (AFM). The results revealed that vanillin had a moderate inhibitive effect, and the adsorption of vanillin obeyed the Temkin adsorption isotherm. For rare earth Ce{sup 4+}, it had a negligible effect. However, incorporation of Ce{sup 4+} with vanillin significantly improved the inhibition performance, and produced strong synergistic inhibition effect. Depending on the results, the synergism mechanism was proposed.

  14. Synergism between rare earth cerium(IV) ion and vanillin on the corrosion of cold rolled steel in 1.0 M HCl solution

    International Nuclear Information System (INIS)

    Li Xianghong; Deng Shuduan; Fu Hui; Mu Guannan

    2008-01-01

    The synergism between rare earth cerium(IV) ion and vanillin on the corrosion of cold rolled steel (CRS) in 1.0 M HCl solution was first investigated by weight loss, potentiodynamic polarization, ultraviolet and visible spectrophotometer (UV-vis), X-ray photoelectron spectroscopy (XPS) and atomic force microscope (AFM). The results revealed that vanillin had a moderate inhibitive effect, and the adsorption of vanillin obeyed the Temkin adsorption isotherm. For rare earth Ce 4+ , it had a negligible effect. However, incorporation of Ce 4+ with vanillin significantly improved the inhibition performance, and produced strong synergistic inhibition effect. Depending on the results, the synergism mechanism was proposed

  15. Corrosion inhibition performance of 2,5-bis(4-dimethylaminophenyl)-1,3,4-oxadiazole for carbon steel in HCl solution: Gravimetric, electrochemical and XPS studies

    Energy Technology Data Exchange (ETDEWEB)

    Bouanis, M.; Tourabi, M.; Nyassi, A. [Laboratoire de Catalyse et de Corrosion des Matériaux (LCCM), Faculté des Sciences, Université Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco); Zarrouk, A. [LCAE-URAC 18, Faculty of Science, First Mohammed University, PO Box 717, M-60 000 Oujda (Morocco); Jama, C. [UMET-ISP, CNRS UMR 8207, ENSCL, Université Lille Nord de France, CS 90108, F-59652 Villeneuve d' Ascq Cedex (France); Bentiss, F., E-mail: fbentiss@gmail.com [Laboratoire de Catalyse et de Corrosion des Matériaux (LCCM), Faculté des Sciences, Université Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco); UMET-ISP, CNRS UMR 8207, ENSCL, Université Lille Nord de France, CS 90108, F-59652 Villeneuve d' Ascq Cedex (France)

    2016-12-15

    Highlights: • 2,5-Bis(4-dimethylaminophenyl)-1,3,4-oxadiazole is good corrosion inhibitor for carbon steel in 1 M HCl. • XPS analysis has provided the composition of adsorbed protective layer on the steel surface. • The adsorption of the investigated 1,3,4-oxadiazole is mainly due to chemisorption. - Abstract: Corrosion inhibition of carbon steel in normal hydrochloric acid solution at 30 °C by 2,5-bis(4-dimethylaminophenyl)-1,3,4-oxadiazole (DAPO) has been studied by weight loss measurements and electrochemical techniques (polarization and AC impedance). The experimental results showed that DAPO acted as an efficient inhibitor against the carbon steel corrosion in 1 M HCl, and its inhibition efficiency increased with the inhibitor concentration reaching a value up to 93% at 1 mM. Polarization studies showed that the DAPO was a mixed-type inhibitor. The adsorption of this 1,3,4-oxadiazole derivative on the carbon steel surface in 1 M HCl solution followed the Langmuir adsorption isotherm and the corresponding value of the standard Gibbs free energy of adsorption (ΔG°{sub ads}) is associated to a chemisorption mechanism. Scanning Electron Microscopy (SEM) and X-Ray Photoelectron Spectroscopy (XPS) analyses were carried out to characterize the chemical composition of the inhibitive film formed on the steel surface. The surfaces studies showed that the inhibitive layer is composed of an iron oxide/hydroxide mixture where DAPO molecules are incorporated. The cytotoxicity of DAPO was also determined using cell culture system.

  16. Guanidine and guanidinium cation in the excited state—theoretical investigation

    Energy Technology Data Exchange (ETDEWEB)

    Antol, Ivana, E-mail: iantol@emma.irb.hr; Glasovac, Zoran [Division of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, P.O. Box 180, HR-10002 Zagreb (Croatia); Crespo-Otero, Rachel; Barbatti, Mario [Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr (Germany)

    2014-08-21

    Diverse ab initio and density-functional-theory methods were used to investigate geometries, energies, and electronic absorption spectra of guanidine and its protonated form, as well as their photo-deactivation processes. It was shown that the guanidine is a weakly absorbing species with the excitation spectrum consisting mostly of transitions to the Rydberg excited states and one valence n-π{sub 4} state. The lowest energy band has a maximum at ca. 6.9 eV (∼180 nm). The protonation of guanidine affects its excitation spectrum substantially. A major shift of the Rydberg states to higher energies is clearly visible and strongly absorbing transitions from the ground state to the π{sub 3}-π{sub 4} and π{sub 2}-π{sub 4} states appears at 7.8 eV (∼160 nm). Three low-lying conical intersections (two for guanidine and one for protonated guanidine) between the ground state and the first excited singlet state were located. They are accessible from the Franck–Condon region through amino N–H stretching and out-of-plane deformations in guanidine and protonated guanidine, respectively. The relaxation of the π{sub 3}-3s Rydberg state via amino N–H bond stretching was hindered by a barrier. The nondissociated conical intersection in protonated guanidine mediates the radiationless deactivation of the compound after excitation into the π{sub 3}-π{sub 4} state. This fact is detrimental for the photostability of guanidine, since its conjugate acid is stable in aqueous solution over a wide pH range and in protein environment, where guanidinium moiety in arginine is expected to be in a protonated form.

  17. The effect of zeolite and diatomite on the corrosion of reinforcement steel in 1 M HCl solution

    Directory of Open Access Journals (Sweden)

    Husnu Gerengi

    2015-01-01

    Full Text Available The greatest disadvantage of reinforced concrete structures is the corrosion occurring in the reinforcement which, over time, causes a reduction in the reinforcement-concrete adherence and eventual sectional loss. The purpose of this study was to reveal the corrosion mechanism of ribbed reinforcement inside additive-free (reference, 20% zeolite-doped and 20% diatomite-doped concrete samples after exposure to 1 M HCl over 240 days. Electrochemical impedance spectroscopy (EIS measurements were made every 10 days. Consequently, it was determined that the 20% zeolite-doped concrete samples had higher concrete and reinforcement resistance compared to the 20% diatomite-doped and the reference concrete, i.e. they exhibited less corrosion.

  18. Corrosion Resistance Behavior of Single-Layer Cathodic Arc PVD Nitride-Base Coatings in 1M HCl and 3.5 pct NaCl Solutions

    Science.gov (United States)

    Adesina, Akeem Yusuf; Gasem, Zuhair M.; Madhan Kumar, Arumugam

    2017-04-01

    The electrochemical behavior of single-layer TiN, CrN, CrAlN, and TiAlN coatings on 304 stainless steel substrate, deposited using state-of-the-art and industrial size cathodic arc PVD machine, were evaluated in 1M HCl and 3.5 pct NaCl solutions. The corrosion behavior of the blank and coated substrates was analyzed by electrochemical impedance spectroscopy (EIS), linear polarization resistance, and potentiodynamic polarization. Bond-coat layers of pure-Ti, pure-Cr, alloyed-CrAl, and alloyed-TiAl for TiN, CrN, CrAlN, and TiAlN coatings were, respectively, first deposited for improved coating adhesion before the actual coating. The average coating thickness was about 1.80 µm. Results showed that the corrosion potentials ( E corr) of the coated substrates were shifted to more noble values which indicated improvement of the coated substrate resistance to corrosion susceptibility. The corrosion current densities were lower for all coated substrates as compared to the blank substrate. Similarly, EIS parameters showed that these coatings possessed improved resistance to defects and pores in similar solution compared to the same nitride coatings developed by magnetron sputtering. The charge transfer resistance ( R ct) can be ranked in the following order: TiAlN > CrN > TiN > CrAlN in both media except in NaCl solution where R ct of TiN is lowest. While the pore resistance ( R po) followed the order: CrAlN > CrN > TiAlN > TiN in HCl solution and TiAlN > CrN > CrAlN > TiN in NaCl solution. It is found that TiAlN coating has the highest protective efficiencies of 79 and 99 pct in 1M HCl and 3.5 pct NaCl, respectively. SEM analysis of the corroded substrates in both media was also presented.

  19. Induction of cytoplasmic petite in yeast by guanidine hydrochloride: combined treatment with other inducing agents.

    Science.gov (United States)

    Villa, L L; Juliani, M H

    1980-06-01

    We have studied the induction of rho- mutants by guanidine hydrochloride (GuHCl) in combination with other known inducers: ethidium bromide (EB), berenil and ultraviolet light. Competition was observed when cells were simultaneously treated with optimal concentrations of EB and GuHCl; on the other hand, treatment of cells with EB in the presence of non-inducing concentrations of GuHCl resulted in the stimulation of rho- induction of EB. Furthermore, using a strain which upon treatment with high EB concentrations shows recovery of respiratory competence, the presence of GuHCl did not interfere either with the early phase of induction or with the recovery phase, but it did interfere in a competitive fashion with the final irreversible phase of EB induction. In the case of berenil, a synergistic effect was seen when cells were pretreated with GuHCl. A synergistic induction was also observed when cells were submitted to UV prior to GuHCl treatment. These results suggest that GuHCl, EB and berenil act via some common step in their rho- induction pathways. Moreover, GuHCl may somehow be decreasing the efficiency of dark repair of ultraviolet lesions on mitochondrial DNA.

  20. Electrocrystallization of Au nanoparticles on glassy carbon from HClO4 solution containing [AuCl4]-

    International Nuclear Information System (INIS)

    Komsiyska, L.; Staikov, G.

    2008-01-01

    The mechanism and kinetics of electrocrystallization of Au nanoparticles on glassy carbon (GC) were investigated in the system GC/1 mM KAuCl 4 + 0.1 M HClO 4 . Experimental results show that the gold electrodeposition follows the so-called Volmer-Weber growth mechanism involving formation and growth of 3D Au nanoparticles on an unmodified GC substrate. The analysis of current transients shows that at relatively positive electrode potentials (E ≥ 0.84 V) the deposition kinetics corresponds to the theoretical model for progressive nucleation and diffusion-controlled 3D growth of Au nanoparticles. The potential dependence of the nucleation rate extracted from the current transients is in agreement with the atomistic theory of nucleation. At sufficiently negative electrode potentials (E ≤ 0.64 V) the nucleation frequency becomes very high and the nucleation occurs instantaneously. Based on this behaviour is applied a potentiostatic double-pulse routine, which allows controlled electrodeposition of Au nanoparticles with a relatively narrow size distribution

  1. COMPARATIVE STUDY OF THE INHIBITIVE ACTION BETWEEN THE BITTER ORANGE LEAF EXTRACT AND ITS CHEMICAL CONSTITUENT LINALOOL ON THE MILD STEEL CORROSION IN HCL SOLUTION

    Directory of Open Access Journals (Sweden)

    Ashraf M. Abdel-Gaber

    Full Text Available Bitter orange, Citrus Aurantium (CA, extract and one of its chemical constituents, Linalool, have been evaluated as a corrosion inhibitor for mild steel in 0.5 mol L-1 hydrochloric acid (HCl solution using potentiodynamic polarization, electrochemical impedance, Fourier transform infrared spectroscopy (FTIR, and atomic force spectroscopy (AFM techniques. Functional groups of CA and Linalool were identified by FTIR spectroscopy. The Potentiodynamic polarization and electrochemical impedance studies showed that CA and Linalool act as mixed type inhibitors. The activation parameters showed that the corrosion inhibition takes place by spontaneous physical adsorption on the mild steel surface. Thermodynamic-kinetic model and Flory-Huggins isotherms were used to investigate the adsorption characteristics of CA and Linalool. The surface morphologies of mild steel specimens were studied using AFM, in which the surface roughness of the metal specimens on a micro scale was characterized.

  2. Effect of Annealing Temperature on the Corrosion Protection of Hot Swaged Ti-54M Alloy in 2 M HCl Pickling Solutions

    Directory of Open Access Journals (Sweden)

    El-Sayed M. Sherif

    2017-01-01

    Full Text Available The corrosion of Ti-54M titanium alloy processed by hot rotary swaging and post-annealed to yield different grain sizes, in 2 M HCl solutions is reported. Two annealing temperatures of 800 °C and 940 °C, followed by air cooling and furnace cooling were used to give homogeneous grain structures of 1.5 and 5 μm, respectively. It has been found that annealing the alloy at 800 °C decreased the corrosion of the alloy, with respect to the hot swaged condition, through increasing its corrosion resistance and decreasing the corrosion current and corrosion rate. Increasing the annealing temperature to 940 °C further decreased the corrosion of the alloy.

  3. Batch and column adsorption behaviors of Se(IV) and Te(IV) on organic and inorganic ion exchangers from HCl solutions

    Energy Technology Data Exchange (ETDEWEB)

    El-Sweify, Fatma H.; Abdel-Fattah, Alaa El-Din A.; Aly, Shorouk M.; Ghamry, Mohamed A. [Atomic Energy Authority, Cairo (Egypt). Hot Laboratories Center; El-Sheikh, Ragaa [Zagazig Univ. (Egypt). Chemistry Dept.

    2017-07-01

    Adsorption behaviors of Se(IV) and Te(IV) on the inorganic ion exchanger ceric tungstate (CeW) was studied under static and dynamic conditions and compared with the adsorption on the organic cation and anion exchangers Dowex-50X8 and AG-2X8, respectively. The radioactive isotopes {sup 75}Se and {sup 123m}Te were used to trace the respective elements. Some parameters affecting the adsorption were investigated under static conditions. In the case of batch technique the adsorption was studied from slightly acidic HCl as well as slightly alkaline media, i.e. at two pH-ranges. Se(IV) and Te(IV) were adsorbed on both the inorganic ion exchanger (CeW) and on AG-2X8, from slightly alkaline solutions. From the similarity of adsorption on both ion exchangers it was clear that (CeW) acts as an anion exchanger. Moreover, the obtained K{sub d}-values for the adsorption on (CeW) were much higher than those for the adsorption on the organic anion exchanger AG-2X8. Se(IV) was not adsorbed on Dowex-50X8 all over the studied pH-range whereas Te(IV) was slightly adsorbed. Loading and elution behaviors of Se(IV) and Te(IV) on columns of AG-2X8 and (CeW) were studied using solutions of HCl of different concentrations. Some good separation alternatives of Se(IV) and Te(IV) under certain conditions were achieved.

  4. Using guanidine-hydrochloride for fast and efficient protein digestion and single-step affinity-purification mass spectrometry

    DEFF Research Database (Denmark)

    Poulsen, Jon Wriedt; Madsen, Christian Toft; Young, Clifford

    2013-01-01

    be optimally completed within 30 min with endoprotease Lys-C. No chemical artifacts were introduced when samples were incubated in Gnd-HCl at 95 °C, making Gnd-HCl an appropriate digestion buffer for shotgun proteomics. Current methodologies for investigating protein-protein interactions (PPIs) often require......Protein digestion is an integral part of the "shotgun" proteomics approach and commonly requires overnight incubation prior to mass spectrometry analysis. Quadruplicate "shotgun" proteomic analysis of whole yeast lysate demonstrated that Guanidine-Hydrochloride (Gnd-HCl) protein digestion can....... To validate the Gnd-HCl approach, label-free PPI analysis of several GFP-tagged yeast deubiquitinating enzymes was performed. The identification of known interaction partners demonstrates the utility of the optimized Gnd-HCl protocol that is also scalable to the 96 well-plate format....

  5. Electrochemical evaluation of antibacterial drugs as environment-friendly inhibitors for corrosion of carbon steel in HCl solution

    Energy Technology Data Exchange (ETDEWEB)

    Golestani, Gh.; Shahidi, M., E-mail: shahidi1965@gmail.com; Ghazanfari, D.

    2014-07-01

    The effect of penicillin G, ampicillin and amoxicillin drugs on the corrosion behavior of carbon steel (ASTM 1015) in 1.0 mol L⁻¹ hydrochloric acid solution was investigated using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and electrochemical noise (EN) techniques. The inhibition efficiency was found to increase with increasing inhibitor concentration. The effect of temperature on the rate of corrosion in the absence and presence of these drugs was also studied. Some thermodynamic parameters were computed from the effect of temperature on corrosion and inhibition processes. Adsorption of these inhibitors was found to obey Langmuir adsorption isotherm. There was a case of mixed mode of adsorption here but while penicillin was adsorbed mainly through chemisorption, two other drugs were adsorbed mainly through physisorption. Potentiodynamic polarization measurements indicated that the inhibitors were of mixed type. In addition, this paper suggests that the electrochemical noise (EN) technique under open circuit conditions as the truly noninvasive electrochemical method can be employed for the quantitative evaluation of corrosion inhibition. This was done by using the standard deviation of partial signal (SDPS) for calculation of the amount of noise charges at the particular interval of frequency, thereby obtaining the inhibition efficiency (IE) of an inhibitor. These IE values showed a reasonable agreement with those obtained from potentiodynamic polarization and EIS measurements.

  6. Electrochemical evaluation of antibacterial drugs as environment-friendly inhibitors for corrosion of carbon steel in HCl solution

    International Nuclear Information System (INIS)

    Golestani, Gh.; Shahidi, M.; Ghazanfari, D.

    2014-01-01

    The effect of penicillin G, ampicillin and amoxicillin drugs on the corrosion behavior of carbon steel (ASTM 1015) in 1.0 mol L −1 hydrochloric acid solution was investigated using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and electrochemical noise (EN) techniques. The inhibition efficiency was found to increase with increasing inhibitor concentration. The effect of temperature on the rate of corrosion in the absence and presence of these drugs was also studied. Some thermodynamic parameters were computed from the effect of temperature on corrosion and inhibition processes. Adsorption of these inhibitors was found to obey Langmuir adsorption isotherm. There was a case of mixed mode of adsorption here but while penicillin was adsorbed mainly through chemisorption, two other drugs were adsorbed mainly through physisorption. Potentiodynamic polarization measurements indicated that the inhibitors were of mixed type. In addition, this paper suggests that the electrochemical noise (EN) technique under open circuit conditions as the truly noninvasive electrochemical method can be employed for the quantitative evaluation of corrosion inhibition. This was done by using the standard deviation of partial signal (SDPS) for calculation of the amount of noise charges at the particular interval of frequency, thereby obtaining the inhibition efficiency (IE) of an inhibitor. These IE values showed a reasonable agreement with those obtained from potentiodynamic polarization and EIS measurements.

  7. Kinetic Analysis of Guanidine Hydrochloride Inactivation of β-Galactosidase in the Presence of Galactose

    Directory of Open Access Journals (Sweden)

    Charles O. Nwamba

    2012-01-01

    Full Text Available Inactivation of purified β-Galactosidase was done with GdnHCl in the absence and presence of varying [galactose] at 50°C and at pH 4.5. Lineweaver-Burk plots of initial velocity data, in the presence and absence of guanidine hydrochloride (GdnHCl and galactose, were used to determine the relevant and max values, with p-nitrophenyl β-D-galactopyranoside (pNPG as substrate, S. Plots of ln([]∞−[] against time in the presence of GdnHCl yielded the inactivation rate constant, A. Plots of A versus [S] at different galactose concentrations were straight lines that became increasingly less steep as the [galactose] increased, showing that A was dependent on [S]. Slopes and intercepts of the 1/[]∞ versus 1/[] yielded +0 and ′+0, the microscopic rate constants for the free enzyme and the enzyme-substrate complex, respectively. Plots of +0 and ′+0 versus [galactose] showed that galactose protected the free enzyme as well as the enzyme-substrate complex (only at the lowest and highest [galactose] against GdnHCl inactivation. In the absence of galactose, GdnHCl exhibited some degree of non-competitive inhibition. In the presence of GdnHCl, galactose exhibited competitive inhibition at the lower [galactose] of 5 mM which changed to non-competitive as the [galactose] increased. The implications of our findings are further discussed.

  8. In vitro algicidal effect of guanidine on Prototheca zopfii genotype 2 strains isolated from clinical and subclinical bovine mastitis.

    Science.gov (United States)

    Alves, A C; Capra, E; Morandi, S; Cremonesi, P; Pantoja, J C F; Langoni, H; de Vargas, A P C; da Costa, M M; Jagielski, T; Bolaños, C A D; Guerra, S T; Ribeiro, M G

    2017-06-01

    Prototheca species have increasingly been reported to be opportunistic pathogens that cause mastitis in dairy herds, and it poses an emergent problem because at present, there are no effective therapies for the treatment of protothecal mastitis. This study investigated the in vitro algicidal effect of guanidine on 75 Prototheca zopfii genotype 2 strains isolated from 75 cases of clinical and subclinical bovine mastitis. All strains were susceptible to guanidine in vitro with minimal algaecide concentrations ranging from 0·001 to 0·035%. Guanidine is known to have a high microbicidal effect and is considered to be a new generation microbicidal compound. It is not toxic to human mucous membranes and conjunctivas at low concentrations and has been used as a disinfectant in swimming pools and as an antiseptic for human wounds. The algicidal action of guanidine at low concentrations indicates that it could be an alternative disinfectant or antiseptic for cleaning of the dairy environment and milking equipment, in pre- and postdipping solutions, in the chemical dry therapy of bovine teats and even in the intramammary therapy of P. zopfii infections. This is the first report of the in vitro algicidal effect of guanidine on P. zopfii strains of animal origin. Prototheca zopfii genotype 2 is an opportunistic pathogen of bovine mastitis. To date, no effective therapies against protothecal mastitis have been developed. The in vitro algicidal effect of guanidine on 75 P. zopfii genotype 2 strains isolated from cows revealed that all of the isolates were susceptible to the compound at low concentrations, which indicates that guanidine may be used as an antiseptic/disinfectant for dairy milking equipment, in pre- and postdipping solutions, and as a chemical dry therapy or an intramammary therapy. This study describes the in vitro algicidal effect of guanidine on P. zopfii for the first time. © 2017 The Society for Applied Microbiology.

  9. The microwave assisted synthesis of 1-alkyl-3-methylimidazolium bromide as potential corrosion inhibitor toward carbon steel in 1 M HCl solution saturated with carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Pasasa, Norman Vincent A., E-mail: npasasa@gmail.com; Bundjali, Bunbun; Wahyuningrum, Deana [Department of Chemistry, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha No. 10 Bandung, Jawa Barat (Indonesia)

    2015-09-30

    Injection of corrosion inhibitor into the fluid current of oil and gas pipelines is an effective way to mitigate corrosion rate on the inner-surface parts of pipelines, especially carbon steel pipelines. In this research, two alkylimidazolium ionic liquids, 1-decyl-3-methylimidazolium bromide (IL1) and 1-dodecyl-3-methylimidazolium bromide (IL2) have been synthesized and studied as a potential corrosion inhibitor towards carbon steel in 1 M HCl solution saturated with carbon dioxide. IL1 and IL2 were synthesized using microwave assisted organic synthesis (MAOS) method. Mass Spectrometry analysis of IL1 and IL2 showed molecular mass [M-H+] peak at 223.2166 and 251.2484, respectively. The FTIR,{sup 1}H-NMR and {sup 13}C-NMR spectra confirmed that IL1 and IL2 were successfully synthesized. Corrosion inhibition activity of IL1 and IL2 were determined using weight loss method. The results showed that IL1 and IL2 have the potential as good corrosion inhibitors with corrosion inhibition efficiency of IL1 and IL2 are 96.00% at 100 ppm (343 K) and 95.60% at 50 ppm (343 K), respectively. The increase in the concentration of IL1 and IL2 tends to improve their corrosion inhibition activities. Analysis of the data obtained from the weight loss method shows that the adsorption of IL1 and IL2 on carbon steel is classified into chemisorption which obeys Langmuir’s adsorption isotherm.

  10. Mineral-solution equilibria—III. The system Na 2OAl 2O 3SiO 2H 2OHCl

    Science.gov (United States)

    Popp, Robert K.; Frantz, John D.

    1980-07-01

    Chemical equilibrium between sodium-aluminum silicate minerals and chloride bearing fluid has been experimentally determined in the range 500-700°C at 1 kbar, using rapid-quench hydrothermal methods and two modifications of the Ag + AgCl acid buffer technique. The temperature dependence of the thermodynamic equilibrium constant ( K) for the reaction NaAlSi 3O 8 + HCl o = NaCl o + 1/2Al 2SiO 5, + 5/2SiO 2 + 1/2H 2O Albite Andalusite Qtz. K = (a NaCl o) /(a H 2O ) 1/2/(a HCl o) can be described by the following equation: log k = -4.437 + 5205.6/ T( K) The data from this study are consistent with experimental results reported by MONTOYA and HEMLEY (1975) for lower temperature equilibria defined by the assemblages albite + paragonite + quartz + fluid and paragonite + andalusite + quartz + fluid. Values of the equilibrium constants for the above reactions were used to estimate the difference in Gibbs free energy of formation between NaCl o and HCl o in the range 400-700°C and 1-2 kbar. Similar calculations using data from phase equilibrium studies reported in the literature were made to determine the difference in Gibbs free energy of formation between KCl o and HCl o. These data permit modelling of the chemical interaction between muscovite + kspar + paragonite + albite + quartz assemblages and chloride-bearing hydrothermal fluids.

  11. Effect of electrolyte composition on the active-to-passive transition behavior of 2205 duplex stainless steel in H2SO4/HCl solutions

    International Nuclear Information System (INIS)

    Lo, I-H.; Fu Yan; Lin, C.-J.; Tsai, W.-T.

    2006-01-01

    Selective dissolution could occur in duplex stainless steels (DSSs) due to the difference in chemical composition between the two constituent phases. In this study, the effect of H 2 SO 4 /HCl composition on the selective dissolution behavior was investigated. The results indicated that there were two distinct peaks appeared in the active-to-passive transition region in the polarization curve. The peak appeared at a lower potential region was associated with the preferential dissolution of ferrite phase while that for austenite at a higher potential. In the concentration ranges of 0.25-2 M of H 2 SO 4 and 0.25-2 M of HCl, the magnitude of the peak anodic current density and the resolution between these two peaks greatly depended on the composition of H 2 SO 4 /HCl. However, the anodic peaks corresponding to the respective dissolutions of ferrite and austenite became less distinguishable when the concentrations of HCl exceeded 1.2 M. Image analysis using scanning electron microscopy (SEM) was performed to confirm the selective dissolution of each constituent phase after potentiostatic polarization at the respective anodic peak potential

  12. The antimicrobial effect of Iseganan HCl oral solution in patients receiving stomatotoxic chemotherapy: analysis from a multicenter, double-blind, placebo-controlled, randomized, phase III clinical trial

    NARCIS (Netherlands)

    Elad, S.; Epstein, J.B.; Raber-Durlacher, J.E.; Donnelly, P.; Strahilevitz, J.

    2012-01-01

    BACKGROUND: Cytotoxic chemotherapy induces changes in the oral microflora that may cause oral and systemic infections in myelosuppressed cancer patients. These complications prompted us to assess the antimicrobial activity of a topical Iseganan HCl mouthwash vs. placebo on the aerobic and

  13. The antimicrobial effect of Iseganan HCl oral solution in patients receiving stomatotoxic chemotherapy: analysis from a multicenter, double-blind, placebo-controlled, randomized, phase III clinical trial

    NARCIS (Netherlands)

    Elad, Sharon; Epstein, Joel B.; Raber-Durlacher, Judith; Donnelly, Peter; Strahilevitz, Jacob

    2012-01-01

    Cytotoxic chemotherapy induces changes in the oral microflora that may cause oral and systemic infections in myelosuppressed cancer patients. These complications prompted us to assess the antimicrobial activity of a topical Iseganan HCl mouthwash vs. placebo on the aerobic and facultatively

  14. Electrochemical quartz crystal microbalance analysis of the oxygen reduction reaction on Pt-based electrodes. Part 2: adsorption of oxygen species and ClO4(-) anions on Pt and Pt-Co alloy in HClO4 solutions.

    Science.gov (United States)

    Omura, J; Yano, H; Tryk, D A; Watanabe, M; Uchida, H

    2014-01-14

    To gain deeper insight into the role of adsorbed oxygenated species in the O2 reduction reaction (ORR) kinetics on platinum and platinum-cobalt alloys for fuel cells, we carried out a series of measurements with the electrochemical quartz crystal microbalance (EQCM) and the rotating disk electrode (RDE) in acid solution. The effects of anion adsorption on the activities for the ORR were first assessed in HClO4 and HF electrolyte solutions at various concentrations. In our previous work (Part 1), we reported that the perchlorate anion adsorbs specifically on bulk-Pt, with a Frumkin-Temkin isotherm, that is, a linear relationship between Δm and log[HClO4]. Here, we find that the specific adsorption on the Pt-skin/Pt3Co alloy was significantly stronger than that on bulk-Pt, in line with its modified electronic properties. The kinetically controlled current density j(k) for the O2 reduction at the Pt-skin/Pt3Co-RDE was about 9 times larger than that of the bulk-Pt-RDE in 0.01 M HClO4 saturated with air, but the j(k) values on Pt-skin/Pt3Co decreased with increasing [HClO4] more steeply than in the case of Pt, due to the blocking of the active sites by the specifically adsorbed ClO4(-). We have detected reversible mass changes for one or more adsorbed oxygen-containing species (Ox = O2, O, OH, H2O) on the Pt-skin/Pt3Co-EQCM and Pt-EQCM in O2-saturated and He-purged 0.01 M HClO4 solutions, in which the specific adsorption of ClO4(-) anions was negligible. The coverages of oxygen species θ(Ox) on the Pt-skin/Pt3Co in the potential range from 0.86 to 0.96 V in the O2-saturated solution were found to be larger than those on pure Pt, providing strong evidence that the higher O2 reduction activity on the Pt3Co is correlated with higher θ(Ox), contrary to the conventional view.

  15. Moessbauer spectroscopic evidence on the heme binding to the proximal histidine in unfolded carbonmonoxy myoglobin by guanidine hydrochloride

    Energy Technology Data Exchange (ETDEWEB)

    Harami, Taikan, E-mail: harami.taikan@jaea.go.jp [Japan Atomic Energy Agency (Japan); Kitao, Shinji; Kobayashi, Yasuhiro [Kyoto University, Research Reactor Institute (Japan); Mitsui, Takaya [Japan Atomic Energy Agency (Japan)

    2008-01-15

    The unfolded heme structure in myoglobin is controversial because of no chance of direct X-ray structure analyses. The unfolding of carbonmonoxy myoglobin (MbCO) by guanidine hydrochloride (GdnHCl) was studied by the Moessbauer spectroscopy. The spectra show the presence of a sort of spectrum in the unfolded MbCO, independent on the concentration of GdnHCl from 1 to 6 M and the increase of the fraction of unfolded MbCO, depending on the GdnHCl concentration. The isomer shift of the iron of heme in the unfolded MbCO was identified to be different from that of the native MbCO as the globin structure in Mb collapses under the unfolded conditions. This result and the existing related Moessbauer data proved that the heme in the unfolded MbCO may remain coordinated to the proximal histidine.

  16. The Inhibitive Effect of 2-Phenyl-3-nitroso-imidazo [1, 2-a]pyridine on the Corrosion of Steel in 0.5 M HCl Acid Solution

    Directory of Open Access Journals (Sweden)

    K. Bouhrira

    2010-01-01

    Full Text Available The effect of 2-phenyl-3-nitroso-imidazo[1,2-a]pyridine (PNIP on the corrosion inhibition of carbon-steel in 0.5 M HCl was studied by weight loss and different electrochemical techniques such as electrochemical impedance spectroscopy (EIS, potentiodynamic polarization. The obtained results showed that PNIP effectively reduces the corrosion rate of carbon steel. Inhibition efficiency (E% increases with inhibitor concentration to attain 88% at 10-3 M. Adsorption of that PNIP on the carbon steel surface in 0.5 M HCl follows the Langmuir isotherm model. E% values obtained from various methods used are in good agreement. SEM characterization of the steel surface is made.

  17. Inactivation and unfolding of protein tyrosine phosphatase from Thermus thermophilus HB27 during urea and guanidine hydrochloride denaturation.

    Directory of Open Access Journals (Sweden)

    Yejing Wang

    Full Text Available The effects of urea and guanidine hydrochloride (GdnHCl on the activity, conformation and unfolding process of protein tyrosine phosphatase (PTPase, a thermostable low molecular weight protein from Thermus thermophilus HB27, have been studied. Enzymatic activity assays showed both urea and GdnHCl resulted in the inactivation of PTPase in a concentration and time-dependent manner. Inactivation kinetics analysis suggested that the inactivation of PTPase induced by urea and GdnHCl were both monophasic and reversible processes, and the effects of urea and GdnHCl on PTPase were similar to that of mixed-type reversible inhibitors. Far-ultraviolet (UV circular dichroism (CD, Tryptophan and 1-anilinonaphthalene -8-sulfonic acid (ANS fluorescence spectral analyses indicated the existence of a partially active and an inactive molten globule-like intermediate during the unfolding processes induced by urea and GdnHCl, respectively. Based on the sequence alignment and the homolog Tt1001 protein structure, we discussed the possible conformational transitions of PTPase induced by urea and GdnHCl and compared the conformations of these unfolding intermediates with the transient states in bovine PTPase and its complex structures in detail. Our results may be able to provide some valuable clues to reveal the relationship between the structure and enzymatic activity, and the unfolding pathway and mechanism of PTPase.

  18. Corrosion inhibition of mild steel in 1 M HCl solution by henna extract: A comparative study of the inhibition by henna and its constituents (Lawsone, Gallic acid, α-D-Glucose and Tannic acid)

    International Nuclear Information System (INIS)

    Ostovari, A.; Hoseinieh, S.M.; Peikari, M.; Shadizadeh, S.R.; Hashemi, S.J.

    2009-01-01

    The inhibitive action of henna extract (Lawsonia inermis) and its main constituents (lawsone, gallic acid, α-D-Glucose and tannic acid) on corrosion of mild steel in 1 M HCl solution was investigated through electrochemical techniques and surface analysis (SEM/EDS). Polarization measurements indicate that all the examined compounds act as a mixed inhibitor and inhibition efficiency increases with inhibitor concentration. Maximum inhibition efficiency (92.06%) is obtained at 1.2 g/l henna extract. Inhibition efficiency increases in the order: lawsone > henna extract > gallic acid > α-D-Glucose > tannic acid. Also, inhibition mechanism and thermodynamic parameters are discussed.

  19. Corrosion inhibition of mild steel in 1 M HCl solution by henna extract: A comparative study of the inhibition by henna and its constituents (Lawsone, Gallic acid, {alpha}-D-Glucose and Tannic acid)

    Energy Technology Data Exchange (ETDEWEB)

    Ostovari, A. [Technical Inspection Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of)], E-mail: A.Ostovari@gmail.com; Hoseinieh, S.M.; Peikari, M. [Technical Inspection Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of); Shadizadeh, S.R. [Petroleum Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of); Hashemi, S.J. [Technical Inspection Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of)

    2009-09-15

    The inhibitive action of henna extract (Lawsonia inermis) and its main constituents (lawsone, gallic acid, {alpha}-D-Glucose and tannic acid) on corrosion of mild steel in 1 M HCl solution was investigated through electrochemical techniques and surface analysis (SEM/EDS). Polarization measurements indicate that all the examined compounds act as a mixed inhibitor and inhibition efficiency increases with inhibitor concentration. Maximum inhibition efficiency (92.06%) is obtained at 1.2 g/l henna extract. Inhibition efficiency increases in the order: lawsone > henna extract > gallic acid > {alpha}-D-Glucose > tannic acid. Also, inhibition mechanism and thermodynamic parameters are discussed.

  20. In situ synthesis, electrochemical and quantum chemical analysis of an amino acid-derived ionic liquid inhibitor for corrosion protection of mild steel in 1M HCl solution

    International Nuclear Information System (INIS)

    Kowsari, E.; Arman, S.Y.; Shahini, M.H.; Zandi, H.; Ehsani, A.; Naderi, R.; PourghasemiHanza, A.; Mehdipour, M.

    2016-01-01

    Highlights: • Electrochemical analysis of effectiveness of an amino acid-derived ionic liquid inhibitor. • Quantum chemical analysis of effectiveness of an amino acid-derived ionic liquid inhibitor. • Finding correlation between electrochemical analysis and quantum chemical analysis. - Abstract: In this study, an amino acid-derived ionic liquid inhibitor, namely tetra-n-butyl ammonium methioninate, was synthesized and the role this inhibitor for corrosion protection of mild steel exposed to 1.0 M HCl was investigated using electrochemical, quantum and surface analysis. By taking advantage of potentiodynamic polarization, the inhibitory action of tetra-n-butyl ammonium methioninate was found to be mainly mixed-type with dominant anodic inhibition. The effectiveness of the inhibitor was also indicated using electrochemical impedance spectroscopy (EIS). Moreover, to provide further insight into the mechanism of inhibition, electrochemical noise (EN) and quantum chemical calculations of the inhibitor were performed.

  1. [Effect of the lysine guanidination on proteomic analysis].

    Science.gov (United States)

    Zheng, Hao; Mao, Jiawei; Pan, Yanbo; Liu, Zhongshan; Liu, Zheyi; Ye, Mingliang; Zou, Hanfa

    2014-04-01

    The guanidination of lysine side chain was paid great attention in recent years. It plays an important role in qualitative and quantitative proteomics. In this study, based on the results of separated peptides extracted from HeLa cells before and after the guanidination by liquid chromatography-tandem mass spectrometry (LC-MS/MS), the effect of the guanidination of three different kinds of peptides was systematically analyzed. It was found that the selectivity of the guanidination of the lysine side chain was as high as 96.8%. The ratio of identified peptides with lysine at C-term to all peptides increased from 51.7% to 57.3% and more new peptides were identified, while the ratio of peptides with lysine in the middle or without lysine changed little. Further study on the ratio of b and y ions indicated that there were more y ions of peptides with lysine at C-term after the guanidination. The results proved that the selective conversion of lysine to homoarginine by the guanidination could increase the sensitivity and selectivity of mass spectrum. The increased basicity and ability to sequester proton of lysine produced more y ions fragmentation information, which contributed to more identified peptides. It concluded that the lysine guanidination can improve the coverage of proteomic analysis.

  2. A Review of Toxicity and Use and Handling Considerations for Guanidine, Guanidine Hydrochloride, and Urea.

    Energy Technology Data Exchange (ETDEWEB)

    Ertell, Katherine GB

    2006-03-27

    This is a technical report prepared for Oregon Sustainable Energy, LLC, under Agreement 06-19 with PNNL's Office of Small Business Programs. The request was to perform a review of the toxicity and safe handling of guanidine. The request was later amended to add urea. This report summarizes the toxicity data available in the scientific literature and provides an interpretation of the results and recommendations for handling these compounds.

  3. Sb{sup III} - Sb{sup V} Exchange Reaction in Hydrochloric: Acid Solutions; Echange Sb{sup III}-Sb{sup V} dans des Solutions d'Acide Chlorhydrique; Reaktsiya obmena Sb(III) - Sb(V) v rastvorakh khloristovodorodnoj kisloty; Intercambio Sb{sup III}-Sb{sup V} en Soluciones de HCl

    Energy Technology Data Exchange (ETDEWEB)

    Kambara, T.; Yamaguchi, K.; Yasuba, S. [Shizuoka University, Shizuoka City (Japan)

    1965-10-15

    The exchange reaction of Sb{sup III} - Sb{sup V} in solutions of low HCl concentrations was studied using {sup 124}Sb as a tracer. The effects of HCl concentrations and chemical forms of antimony on the exchange rate were investigated. The HCl concentrations of the antimony solutions ((Sb{sup III}) =(Sb{sup V}) = 6.8 x 10{sup -4}M) were changed from 0.8 to 4.0M and the half-time for the exchange was measured by plotting log (1 - F) versus time t to calculate the exchange rate assuming the second-ordet reaction. It was found that the exchange rate was sharply increased with the increase of HCl concentrations (at 25 Degree-Sign C, from 0.8 to 2.0M) and at 2.0M HCl concentration the rate reached the maximum, from which the rate was decreased with the increase of HCl concentrations (at 25 Degree-Sign C, from 2.0 to 4.0M). Two sorts of Sb{sup V} species were used for our investigations, i.e. one was used directly after the dilution of 10M HCl Sb{sup V} solution with water and the other was used after 24 hours standing at room temperature from the dilution. (The Sb{sup III} species were also kept standing after preparation from 10M HCl Sb{sup III} solution.) In both cases the maximum rates were found to exist at 2.0M HCl concentration. The rate R{sub 1} for the former (directly after dilution) was 4.5 x 10{sup -6} mole litre{sup -1} min{sup -1} and the rate R{sub 2} for the latter (24 hours standing) was 1.2 x 10{sup -}{sub 6} mole litre. Also the activation energy for these cases was found to be 12.2 kcal/mole and 19.1 kcal/mole. By spectrophotometric studies, the Sb{sup V} species of the former type were found to be mainly consisting of SbCl{sup -}{sub 6} and the species of the latter type to be of SbCl{sub 4}(OH){sup -}{sub 2}, etc. Besides these facts the form of Sb{sup III} species was found to have no influence on the exchange rate. A much sharper increase of the exchange rate was observed when the HCl concentration of the antimony solution was fixed at 0.8M and

  4. Guanidine hydrochloride denaturation of human serum albumin originates by local unfolding of some stable loops in domain III.

    Science.gov (United States)

    Ahmad, Basir; Ahmed, Md Zulfazal; Haq, Soghra Khatun; Khan, Rizwan Hasan

    2005-06-15

    The effect of guanidine hydrochloride (GnHCl) on the global stability of human serum albumin (HSA) has been studied by fluorescence and circular dichroism spectroscopic measurements. The differential stability of native conformation of three HSA domains were explored by using domain-specific ligands, hemin (domain I), chloroform (domain II), bilirubin (at domain I/domain II interface) and diazepam (domain III). GnHCl induced unfolding transition curves as monitored by probes for secondary and tertiary structures were cooperative but noncoincidental. A strong ANS binding to the protein was observed around 1.8 M GnHCl, suggesting existence of intermediate states in the unfolding pathway of HSA. A gradual decrease (in the GnHCl concentration range 0.0-1.8 M) in the binding of diazepam indicates that domain III is the most labile to GnHCl denaturation. A significant increase in the binding of bilirubin up to 1.4 M GnHCl and decrease thereafter leading to complete abolishment of bilirubin binding at around 2.0 M GnHCl suggest favorable rearrangement and separation of domains I and II at 1.4 and 2.0 M GnHCl concentration, respectively. Above 1.6 M GnHCl, decrease of the binding of hemin, a ligand for domain I, chloroform, which binds in domain II and lone tryptophanyl fluorescence (Trp-214 located in domain II) indicate that at higher concentration of GnHCl domains I and II start unfolding simultaneously but the stability of domain I (7.4 Kcal/mol) is much more than domain II (4.3 Kcal/mol). A pictorial model for the unfolding of HSA domains, consistent with all these results, has been formulated, suggesting that domain III is the most labile followed by domain II while domain I is the most stable. A molten globule like state of domain III around 1.8 M GnHCl has also been identified and characterized.

  5. Isocyanate leading to Guanidines/Urea derivatives formation

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 128; Issue 6. Zinc catalyzed Guanylation reaction of Amines with Carbodiimides/ Isocyanate leading to Guanidines/Urea derivatives formation. JAYEETA BHATTACHARJEE MITALI SACHDEVA INDRANI BANERJEE TARUN K PANDA. Regular Article Volume 128 ...

  6. An in-situ X-ray absorption spectroelectrochemical study of the electroreduction of uranium ions in HCl, HNO{sub 3}, and Na{sub 2}CO{sub 3} solutions

    Energy Technology Data Exchange (ETDEWEB)

    Uehara, Akihiro; Fujii, Toshiyuki; Yamana, Hajimu [Kyoto Univ., Osaka (Japan). Div. of Nuclear Engineering Science; Okamoto, Yoshihiro [Japan Atomic Energy Agency, Ibaraki (Japan). Quantum Beam Science Directorate

    2016-04-01

    A spectroelectrochemical cell was fabricated for in-situ X-ray absorption spectroscopy (in-situ XAS). The XAS spectra of the uranium L{sub III} edge were monitored in electrolyte solutions during the electrochemical reduction. Tetravalent uranium, U{sup 4+}, in 1 mol dm{sup -3} (M) hydrochloric acid (HCl) was electrochemically prepared from hexavalent uranium, UO{sub 2}{sup 2+}, by constant current electrolysis, and the extended X-ray absorption fine structure (EXAFS) was analyzed. The concentration ratio of UO{sub 2}{sup 2+} and U{sup 4+}, which were formed via the disproportionation of pentavalent uranium, UO{sub 2}{sup +}, during the electrolysis, were calculated based on the intensity of the signal for the two axial oxygen atoms in the linear UO{sub 2}{sup 2+} unit, the U-O{sub ax}, bond that had a radial structural function. The apparent redox potential of the UO{sub 2}{sup 2+}/U{sup 4+} couple in 1 M HCl was determined based on the Nernst equation using the concentrations of UO{sub 2}{sup 2+} and U{sup 4+}. The electrode potential was shown to be close to the formal potential of the UO{sub 2}{sup 2+}/UO{sub 2}{sup +} couple as reported previously. This result indicates that the UO{sub 2}{sup +} that was formed electrochemically at the electrode disproportionated to form UO{sub 2}{sup 2+} and U{sup 4+} in the bulk solution. The in-situ XAS of UO{sub 2}{sup 2+} in 0.1 M nitric acid was also performed. The U{sup 4+} that formed was partially re-oxidized to UO{sub 2}{sup 2+} by the NO{sub 3}{sup -} present in the solution. The formation of the UO{sub 2}{sup +} carbonato complex was observed by in-situ XAS in a 1 M sodium carbonate solution during the bulk electrolysis. The edge jump of the X-ray absorption near edge structure (XANES) spectrum shifted from 17.164 to 17.163 keV, and the bond distances of U-O{sub ax} and U-O for CO{sub 3}{sup 2-} increased from 1.78 to 1.88 Aa and from 2.42 to 2.53 Aa, respectively, because of the reduction of the UO{sub 2}{sup 2

  7. Excellent enhancement of corrosion properties of Fe–9Al–30Mn–1.8C alloy in 3.5% NaCl and 10% HCl aqueous solutions using gas nitriding treatment

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yung-Chang; Lin, Chih-Lung; Chao, Chuen-Guang; Liu, Tzeng-Feng, E-mail: Lewischen815@gmail.com

    2015-06-05

    Highlights: • The FeAlMnC alloy was gas-nitrided to simultaneously achieve the aging effect. • Anti-corrosion components AlN, Fe{sub 3}N and Fe{sub 4}N were identified by using GIXRD method. • The present nitrided alloy showed a great improvement in corrosion resistance. • The nitrided sample showed an excellent coherence between nitrided layer and matrix. • The nitrided and then stretched sample maintained satisfactory corrosion behavior. - Abstract: The as-quenched Fe–9.0Al–30Mn–1.8C (in wt.%) alloy gas nitrided at 550 °C for 4 h show excellent corrosion resistance investigated in 3.5% NaCl and 10% HCl solutions. Owing to the high corrosion resistance components, the gas-nitrided layer consists mainly of AlN with a slight amount of Fe{sub 3}N and Fe{sub 4}N identified by grazing incidence X-ray diffraction technique. Therefore, the pitting potential and corrosion potential of the nitrided sample are +1860 mV and +30 mV, respectively. Surprisingly, it is worthy to be pointed out that the nitrided and then tensile-tested alloy reveals very shallow in fracture depth and the excellent lattice coherence is shown between the nitrided layer and the substrate. Moreover, due to the extremely high nitrogen concentration (about 17–18 wt.%) at stretched surface, the corrosion resistance of present gas-nitrided and then tensile-tested alloy is superior to those optimally gas-nitrided or plasma-nitrided high-strength alloy steels, as well as martensitic stainless steels. The nitrided and then stretched alloy still retains a satisfactory corrosion resistance (E{sub pit} = +890 mV; E{sub corr} = +10 mV). Furthermore, only nanoscale-size pits were observed on the corroded surface after being immersed in 10% HCl for 24 h.

  8. Self-assembly, foaming, and emulsifying properties of sodium alkyl carboxylate/guanidine hydrochloride aqueous mixtures.

    Science.gov (United States)

    Fameau, Anne-Laure; Houinsou-Houssou, Bérénice; Ventureira, Jorge Luis; Navailles, Laurence; Nallet, Frédéric; Novales, Bruno; Douliez, Jean-Paul

    2011-04-19

    Unsaturated fatty acids may be extracted from various agricultural resources and are widely used as soaps in the industry. However, there also exist a large variety of saturated and hydroxy fatty acids in nature, but their metal salts crystallize at room temperature in water, hampering their use in biological and chemical studies or for industrial applications. Addition of guanidine hydrochloride (GuHCl) to sodium salt of myristic acid has been shown to prevent its crystallization in water, forming stable flat bilayers at room temperature. Herein, we extend this finding to two other saturated fatty acids (palmitic and stearic acids) and two hydroxyl fatty acids (juniperic and 12 hydroxy stearic acids) and study more deeply (by using small angle neutron scattering) the supramolecular assemblies formed in both saturated and hydroxyl fatty acid systems. In addition, we take the advantage that crystallization no longer occurs at room temperature in the presence of GuHCl to study the foaming and emulsifying properties of those fatty acid dispersions. Briefly, our results show that all fatty acids, even juniperic acid, which is a bola lipid, are arranged in a bilayer structure that may be interdigitated. Depending on the nature of the fatty acid, the systems exhibit good foamability and foam stability (except for juniperic acid), and emulsion stability was good. Those findings should be of interest for using saturated long chain (and hydroxyl) fatty acids as surfactants for detergency or even materials chemistry. © 2011 American Chemical Society

  9. Tris (isodecyl) guanidine degradation in the MCU system

    Energy Technology Data Exchange (ETDEWEB)

    Peters, T. B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-06-01

    The current solvent blend consists of four components; an extractant, the modifier, a suppressor, and the diluent. Of the four components, only the suppressor – tris(isodecyl)guanidine (TiDG) has exhibited an appreciable depletion rate during facility operations.∇ Using data derived from MCU process samples, SRNL derived a method to predict the TiDG depletion based upon time and volume of feed processed. With the current data set, the following formula can estimate the TiDG concentrations after processing: At = [A0×exp(-0.000900×t)] – [5.39E-06×volume] where At is the TiDG concentration (mM) at time t (days), A0 is the TiDG concentration (mM) at time = 0, and volume is the amount of salt solution processed in gallons from time 0 to time t. The ability to use this formula as a predictive tool is limited due to the number of data points obtained for this scope of work. As such, this formula should not be used to precisely predict future TiDG concentrations.

  10. GdnHCl-induced unfolding intermediate in the mitochondrial carbonic anhydrase VA.

    Science.gov (United States)

    Idrees, Danish; Prakash, Amresh; Haque, Md Anzarul; Islam, Asimul; Hassan, Md Imtaiyaz; Ahmad, Faizan

    2016-10-01

    Carbonic anhydrase VA (CAVA) is a mitochondrial enzyme belonging to the α-family of CAs, which is involved in several physiological processes including ureagenesis, lipogenesis, gluconeogenesis and neuronal transmission. Here, we have tried to understand the folding mechanism of CAVA using guanidine hydrochloride (GdnHCl)-induced denaturation at pH 8.0 and 25°C. The conformational stability was measured from the GdnHCl-induced denaturation study of CAVA monitored by circular dichroism (CD) and fluorescence measurements. On increasing the concentration of GdnHCl up to 5.0, a stable intermediate was observed between the concentrations 3.25M to 3.40M of the denaturant. However, CAVA gets completely denatured at 4.0M GdnHCl. The existence of a stable intermediate state was validated by 1-anilinonaphthalene-8-sulfonic acid (ANS binding) fluorescence and near-UV CD measurements. In silico studies were also performed to analyse the effect of GdnHCl on the structure and stability of CAVA under explicit conditions. Molecular dynamics simulations for 40ns were carried out and a well-defined correlation was established for both in vitro and in silico studies. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Development of Antimicrobial Coatings by Atmospheric Pressure Plasma Using a Guanidine-Based Precursor

    Science.gov (United States)

    2013-10-29

    AP- PECVD) process to develop coatings from a guanidine-derived monomer, 1,1,3,3-tetramethylguanidine ( TMG ), that impart antimicrobial behavior onto...cleaned in ethanol and dried in open air. The antimicrobial agent, 1,1,3,3- tetramethylguanidine ( TMG ) (99%, Aldrich), was used as received. TMG ...solutions used in the deposition process included 1.0, 5.0, and 10.0% (w/w) of TMG in deionized water (Milli-Q, 18 MΩ•cm) and were used to study the role

  12. Cashew Nut Testa Tannin: Assessing its Effects on the Corrosion of Aluminium in HCl

    OpenAIRE

    Nnaji, Nnaemeka J. N; Obi-Egbedi, Nelson O; Okoye, Chukwuma O. B

    2014-01-01

    Cashew nut testa tannin (CASTAN) has been found to inhibit the corrosion of aluminium in hydrochloric acid solutions using gravimetric, thermometric and UV/visible spectrophotometric techniques. CASTAN inhibition was by adsorption on aluminium following Temkin isotherm in 0.1 M HCl and Langmuir isotherm in 0.5 M and 2.0 M HCl at 303 Kelvin. Physical adsorption on aluminium has been proposed in studied HCl solutions; therefore, CASTAN is a cathodic inhibitor. Earlier reports (1) showed CASTAN ...

  13. A preliminary safety evaluation of polyhexamethylene guanidine hydrochloride.

    Science.gov (United States)

    Asiedu-Gyekye, Isaac Julius; Mahmood, Seidu Abdulai; Awortwe, Charles; Nyarko, Alexander Kwadwo

    2014-01-01

    Polyhexamethylene guanidine hydrochloride (PHMGH) is used worldwide as an antimicrobial agent with broad spectra of activity and also for treating pool water. This non-GLP preliminary study aims at investigating in a subchronic toxicity study possible effects at supra-optimal doses of this biocide. Both acute and subchronic toxicity studies were conducted. LD(50) for PHMGH was estimated to be 600 mg/kg (ie LC(50) 2 ml of 7.5% solution) when administered as a single dose by gavage via a stomach tube in accordance with the expected route of administration. The acute studies showed that the median lethal dose (LD(50)) of 600 mg/kg was accompanied by signs of neurotoxicity. Haematological and biochemical parameters of subchronic toxicity studies were non-significant. Subchronic doses of 0.006 mg/kg, 0.012 mg/kg and 0.036 mg/kg were administered. 20% of the animals at a dose of 0.006 mg/kg and 0.036 mg/kg showed mild degrees of hydropic changes in proximal tubules while 10% of animals at all the doses had their liver tissues showing local areas of mild pericentral hepatocytes degeneration. PHMGH did not produce any major organ defect with regard to the kidney, heart, and liver. The LD(50) was much higher than the recommended dosage by a factor of about 50,000. The recommended residual concentration is far less than the median lethal dose using rats as test subjects. These results could serve as a basis for investigating the full toxicological profile if it is to be used for the treatment of raw water to make it potable. © The Author(s) 2014.

  14. Guanidine-catalyzed enantioselective desymmetrization of meso-aziridines

    KAUST Repository

    Zhang, Yan

    2011-01-01

    An amino-indanol derived chiral guanidine was developed as an efficient Brønsted base catalyst for the desymmetrization of meso-aziridines with both thiols and carbamodithioic acids as nucleophiles, which provided 1,2-difunctionalized ring-opened products in high yields and enantioselectivities. © The Royal Society of Chemistry.

  15. Novel guanidine-based inhibitors of inosine monophosphate dehydrogenase.

    Science.gov (United States)

    Iwanowicz, Edwin J; Watterson, Scott H; Liu, Chunjian; Gu, Henry H; Mitt, Toomas; Leftheris, Katerina; Barrish, Joel C; Fleener, Catherine A; Rouleau, Katherine; Sherbina, N Z; Hollenbaugh, Diane L

    2002-10-21

    A series of novel guanidine-based small molecule inhibitors of inosine monophosphate dehydrogenase (IMPDH) was explored. IMPDH catalyzes the rate determining step in guanine nucleotide biosynthesis and is a target for anticancer, immunosuppressive and antiviral therapy. The synthesis and the structure-activity relationships (SARs), derived from in vitro studies, for this new series of inhibitors is given.

  16. Synthesis of substituted guanidines using Zn–Al hydrotalcite catalyst

    Indian Academy of Sciences (India)

    Zn–Al HT was prepared by co-precipitation method and charac- terized by ... tion of highly functionalized guanidines.4 Linton et al. explained a ..... Pi C, Zhu Z, Weng L, Chen Z and Zhou X 2007 Chem. Commun. ... J P 2000 J. Mater. Chem.

  17. Enhanced removal of Se(VI) from water via pre-corrosion of zero-valent iron using H2O2/HCl: Effect of solution chemistry and mechanism investigation.

    Science.gov (United States)

    Shan, Chao; Chen, Jiajia; Yang, Zhe; Jia, Huichao; Guan, Xiaohong; Zhang, Weiming; Pan, Bingcai

    2018-04-15

    Although the removal of Se(VI) from water by using zero-valent iron (ZVI) is a promising method, passivation of ZVI severely inhibits its performance. To overcome such issue, we proposed an efficient technique to enhance Se(VI) removal via pre-corrosion of ZVI with H 2 O 2 /HCl in a short time (15 min). The resultant pcZVI suspension was weakly acidic (pH 4.56) and contained abundant aqueous Fe 2+ . 57 Fe Mössbauer spectroscopy showed that pcZVI mainly consisted of Fe 0 (66.2%), hydrated ferric oxide (26.3%), and Fe 3 O 4 (7.5%). Efficient removal of Se(VI) from sulfate-rich solution was achieved by pcZVI compared with ZVI (in the absence and presence of H 2 O 2 ) and acid-pretreated ZVI. Moreover, the efficient removal of Se(VI) by pcZVI sustained over a broad pH range (3-9) due to its strong buffering power. The presence of chloride, carbonate, nitrate, and common cations (Na + , K + , Ca 2+ , and Mg 2+ ) posed negligible influence on the removal of Se(VI) by pcZVI, while the inhibitory effect induced by sulfate, silicate, and phosphate indicated the significance of Se(VI) adsorption as a prerequisite step for its removal. The consumption of aqueous Fe 2+ was associated with Se(VI) removal, and X-ray absorption near edge structure revealed that the main pathway for Se(VI) removal by pcZVI was a stepwise reduction of Se(VI) to Se(IV) and then Se 0 as the dominant final state (78.2%). Moreover, higher electron selectivity of pcZVI was attributed to the enhanced enrichment of Se oxyanions prior to their reduction. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Probing Conformational Stability and Dynamics of Erythroid and Nonerythroid Spectrin: Effects of Urea and Guanidine Hydrochloride

    Science.gov (United States)

    Patra, Malay; Mukhopadhyay, Chaitali; Chakrabarti, Abhijit

    2015-01-01

    We have studied the conformational stability of the two homologous membrane skeletal proteins, the erythroid and non-erythroid spectrins, in their dimeric and tetrameric forms respectively during unfolding in the presence of urea and guanidine hydrochloride (GuHCl). Fluorescence and circular dichroism (CD) spectroscopy have been used to study the changes of intrinsic tryptophan fluorescence, anisotropy, far UV-CD and extrinsic fluorescence of bound 1-anilinonapthalene-8-sulfonic acid (ANS). Chemical unfolding of both proteins were reversible and could be described as a two state transition. The folded erythroid spectrin and non-erythroid spectrin were directly converted to unfolded monomer without formation of any intermediate. Fluorescence quenching, anisotropy, ANS binding and dynamic light scattering data suggest that in presence of low concentrations of the denaturants (up-to 1M) hydrogen bonding network and van der Waals interaction play a role inducing changes in quaternary as well as tertiary structures without complete dissociation of the subunits. This is the first report of two large worm like, multi-domain proteins obeying twofold rule which is commonly found in small globular proteins. The free energy of stabilization (ΔGu H 2 0) for the dimeric spectrin has been 20 kcal/mol lesser than the tetrameric from. PMID:25617632

  19. QSAR Study of Sucrose and Guanidine Derivatives

    African Journals Online (AJOL)

    NICO

    CAChe Pro software by using eight descriptors,viz.electron affinity, ionization potential, electrophilicity index, total ... development of the AH-B theory of sweetness proposed by .... form of the solution to the quantum mechanical equation as.

  20. Demineralisation of a semianthracite char with molten salts/HCl

    International Nuclear Information System (INIS)

    Alfaro-Dominguez, M.; Sanchez Bajo, F.

    2006-01-01

    The effects of chemical heat treatments of a semianthracite char (AC) on the composition of the mineral fraction of the material are investigated. The starting char was first treated with a mixture of LiCl/KCl or LiCl/KCl/CaO at 743, 873 or 1173 K and the products obtained were then washed thoroughly with distilled water. A small fraction of these samples were treated with 10 -3 M HCl solution. The composition changes were studied by X-ray diffraction. The predominant mineral components initially present in the starting char are quartz, mullite, muscovite and/or kaolinite and oldhamite. The treatments of AC resulted in significant changes in the mineral fraction of the material, in particular when LiCl/KCl/CaO was used. In this case, spurrite, γ-calcium orthosilicate and gehlenite were formed, which were eliminated by treatment with 10 -3 M HCl solution

  1. Demineralisation of a semianthracite char with molten salts/HCl

    Energy Technology Data Exchange (ETDEWEB)

    Alfaro-Dominguez, M. [Departamento de Electronica e Ingenieria Electromecanica, Escuela de Ingenierias Industriales, Universidad de Extremadura, Avda de Elvas s/n, 06071 Badajoz (Spain)]. E-mail: malfaro@unex.es; Sanchez Bajo, F. [Departamento de Electronica e Ingenieria Electromecanica, Escuela de Ingenierias Industriales, Universidad de Extremadura, Avda de Elvas s/n, 06071 Badajoz (Spain)

    2006-06-30

    The effects of chemical heat treatments of a semianthracite char (AC) on the composition of the mineral fraction of the material are investigated. The starting char was first treated with a mixture of LiCl/KCl or LiCl/KCl/CaO at 743, 873 or 1173 K and the products obtained were then washed thoroughly with distilled water. A small fraction of these samples were treated with 10{sup -3} M HCl solution. The composition changes were studied by X-ray diffraction. The predominant mineral components initially present in the starting char are quartz, mullite, muscovite and/or kaolinite and oldhamite. The treatments of AC resulted in significant changes in the mineral fraction of the material, in particular when LiCl/KCl/CaO was used. In this case, spurrite, {gamma}-calcium orthosilicate and gehlenite were formed, which were eliminated by treatment with 10{sup -3} M HCl solution.

  2. Gas-Microjet Reactive Scattering: Collisions of HCl and DCl with Cool Salty Water.

    Science.gov (United States)

    Faust, Jennifer A; Sobyra, Thomas B; Nathanson, Gilbert M

    2016-02-18

    Liquid microjets provide a powerful means to investigate reactions of gases with salty water in vacuum while minimizing gas-vapor collisions. We use this technique to explore the fate of gaseous HCl and DCl molecules impinging on 8 molal LiCl and LiBr solutions at 238 K. The experiments reveal that HCl or DCl evaporate infrequently if they become thermally accommodated at the surface of either solution. In particular, we observe minimal thermal desorption of HCl following HCl collisions and no distinct evidence for rapid, interfacial DCl→HCl exchange following DCl collisions. These results imply that surface thermal motions are not generally strong enough to propel momentarily trapped HCl or DCl back into the gas phase before they ionize and disappear into solution. Instead, only HCl and DCl molecules that scatter directly from the surface escape entry. These recoiling molecules transfer less energy upon collision to LiBr/H2O than to LiCl/H2O, reflecting the heavier mass of Br(-) than of Cl(-) in the interfacial region.

  3. Unfolding Studies of the Cysteine Protease Baupain, a Papain-Like Enzyme from Leaves of Bauhinia forficata: Effect of pH, Guanidine Hydrochloride and Temperature

    Directory of Open Access Journals (Sweden)

    Rosemeire A. Silva-Lucca

    2013-12-01

    Full Text Available Baupain belongs to the α+β class of proteins with a secondary structure-content of 44% α-helix, 16% β-sheet and 12% β-turn. The structural transition induced by pH was found to be noncooperative, with no important differences observed in the pH range from 3.0 to 10.5. At pH 2.0 the protein presented substantial non-native structure with strong ANS binding. Guanidine hydrochloride (GdnHCl-induced unfolding did not change the protein structure significantly until 4.0 M, indicating the high rigidity of the molecule. The unfolding was cooperative, as seen by the sigmoidal transition curves with midpoints at 4.7 ± 0.2 M and 5.0 ± 0.2 M GdnHCl, as measured by CD and fluorescence spectroscopy. A red shift of 7 nm in intrinsic fluorescence was observed with 6.0 M GdnHCl. Temperature-induced unfolding of baupain was incomplete, and at least 35% of the native structure of the protein was retained, even at high temperature (90 °C. Baupain showed characteristics of a molten globule state, due to preferential ANS binding at pH 2.0 in comparison to the native form (pH 7.0 and completely unfolded (6.0 M GdnHCl state. Combined with information about N-terminal sequence similarity, these results allow us to include baupain in the papain superfamily.

  4. Unfolding studies of the cysteine protease baupain, a papain-like enzyme from leaves of Bauhinia forficata: effect of pH, guanidine hydrochloride and temperature.

    Science.gov (United States)

    Silva-Lucca, Rosemeire A; Andrade, Sheila S; Ferreira, Rodrigo Silva; Sampaio, Misako U; Oliva, Maria Luiza V

    2013-12-24

    Baupain belongs to the α+β class of proteins with a secondary structure-content of 44% α-helix, 16% β-sheet and 12% β-turn. The structural transition induced by pH was found to be noncooperative, with no important differences observed in the pH range from 3.0 to 10.5. At pH 2.0 the protein presented substantial non-native structure with strong ANS binding. Guanidine hydrochloride (GdnHCl)-induced unfolding did not change the protein structure significantly until 4.0 M, indicating the high rigidity of the molecule. The unfolding was cooperative, as seen by the sigmoidal transition curves with midpoints at 4.7±0.2 M and 5.0±0.2 M GdnHCl, as measured by CD and fluorescence spectroscopy. A red shift of 7 nm in intrinsic fluorescence was observed with 6.0 M GdnHCl. Temperature-induced unfolding of baupain was incomplete, and at least 35% of the native structure of the protein was retained, even at high temperature (90 °C). Baupain showed characteristics of a molten globule state, due to preferential ANS binding at pH 2.0 in comparison to the native form (pH 7.0) and completely unfolded (6.0 M GdnHCl) state. Combined with information about N-terminal sequence similarity, these results allow us to include baupain in the papain superfamily.

  5. Application of phosphating techniques to aluminium and carbon steel surfaces using nitro guanidine as oxidizing agent

    International Nuclear Information System (INIS)

    Briseno M, S.A.

    1995-01-01

    Phosphate coatings are inorganic crystalline deposits laid down uniformly on properly prepared surfaces by a chemical reaction with the treated base metal. The reaction consists in dissolving some surface metal by acid attack and then causing surface neutralization of the phosphate solution with consequent precipitation of the phosphate coating. Phosphate coatings do not provide appreciable corrosion protection in themselves. They are useful mainly as a base for paints, ensuring good adherence of paint to steel and decreasing the tendency for corrosion to under cut the paint film at scratches or other defects. In this work firstly were realized phosphate on standard carbon steel, employing technical of cold phosphate (at 40 Centigrade degrees and with a treatment time of 30 minutes) and hot phosphate (at 88 Centigrade degrees and with a treatment time of 15 minutes), where with this last were obtained the best results. Both methods used phosphate solutions of Zn/Mn and using as catalyst Nitro guanidine. Aluminium surfaces were phosphate used solutions of Cr and as catalyst Sodium bi fluoride. The phosphating on this surface were realized at temperature of 50 Centigrade degrees and with a treatment time of 10 minutes. In this work were obtained a new phosphate coatings on steel surfaces, these coatings were realized with a phosphate solution manufactured with the precipitates gathered during the hot phosphating on carbon steel. These coatings show excellent physical characteristics and of corrosion resistance. Were determined the physical testings of the coatings phosphate obtained on carbon steel and aluminium surfaces. These testing were: roughness, thickness, microhardness and adhesion. The best results were showed in carbon steel phosphate with precipitated solutions. The technical of analysis for activation with thermic neutrons was used to determine the phosphate coatings composition. Finally, corrosion testings were realized by means of two methods

  6. Highly sensitive determination of poly(hexamethylene guanidine) by Rayleigh scattering using aggregation of silver nanoparticles

    International Nuclear Information System (INIS)

    Artemyeva, Anastasia A.; Sharov, Andrei V.; Beklemishev, Mikhail K.; Samarina, Tatyana O.; Abramchuk, Sergei S.; Ovcharenko, Elena O.; Dityuk, Alexander I.; Efimov, Konstantin M.

    2015-01-01

    We have found that low concentrations of the polycationic disinfectant poly(hexamethylene guanidine) hydrochloride (PHMG) induce the aggregation of citrate-stabilized silver nanoparticles (AgNPs) in aqueous solution. Based on this finding, we have worked out a method to the determination of PHMG. The protocol includes the steps of (a) centrifuging the water sample, (b) addition of an aliquot of the colloidal solution of the AgNPs, and (c) measurement of the intensity of scattered light. The method is surprisingly selective in that comparable concentrations of surfactants, humic acids and protein do not interfere. Besides, an up to 50 mM concentration NaCl, and up to 5 mM of Mg(II) or Ca(II) are tolerated. Other cationic polyelectrolytes, polyethyleneimine and poly(dimethyldiallyammonium chloride), also cause aggregation of AgNPs but to a lesser extent. The determination of PHMG was performed in spiked samples (run-off, tap and swimming pool waters) with detection limits of 2·10 −8 , 4·10 −7 , and 6·10 −6 M (by monomer unit), respectively. The linear ranges are wider and the detection limits are lower than those of known spectrophotometric methods. It is necessary, however, to correct the calibration plot for background scattering by the sample and to establish a calibration plot for each kind of water sample. Notwithstanding this, the approach is attractive because it is sensitive, rapid, and simple. (author)

  7. Synthesis of Guanidines via Reaction of Amines with Carbodiimides in the Presence of Ionic Liquid

    Directory of Open Access Journals (Sweden)

    Foad Shaghayeghi Toosi

    2016-01-01

    Full Text Available Different ionic liquids (ILs were synthesized and evaluated for the preparation of substituted guanidines from the reaction of amines and carbodiimides. 1-methylimidazolium tetrafluoroborate [HMIm]BF4 was found to be the best ionic liquid for this reaction. This IL acted as a promoter for the addition of primary and secondary amines to carbodiimides. By this efficient approach, various guanidines were prepared in excellent yields.

  8. Antimicrobial activity of polyhexamethylene guanidine phosphate in comparison to chlorhexidine using the quantitative suspension method.

    Science.gov (United States)

    Vitt, A; Sofrata, A; Slizen, V; Sugars, R V; Gustafsson, A; Gudkova, E I; Kazeko, L A; Ramberg, P; Buhlin, K

    2015-07-17

    Polyhexamethylene guanidine phosphate (PHMG-P) belongs to the polymeric guanidine family of biocides and contains a phosphate group, which may confer better solubility, a detoxifying effect and may change the kinetics and dynamics of PHMG-P interactions with microorganisms. Limited data regarding PHMG-P activity against periodontopathogenic and cariogenic microorganisms necessitates studies in this area. Aim is to evaluate polyhexamethylene guanidine phosphate antimicrobial activity in comparison to chlorhexidine. Quantitative suspension method was used enrolling Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Streptococcus mutans and Lactobacillus acidophilus. Both tested antiseptics at their clinically-used concentrations, of 0.2% (w/v) and 1% (w/v), correspondingly provided swift bactericidal effects against S. aureus, P. aeruginosa, E. coli and C. albicans, A. actinomycetemcomitans and P. gingivalis with reduction factors higher than 6.0. Diluted polyhexamethylene guanidine phosphate and chlorhexidine to 0.05% continued to display anti-bacterial activity and decreased titers of standard quality control, periopathogens to below 1.0 × 10(3) colony forming units/ml, albeit requiring prolonged exposure time. To achieve a bactericidal effect against S. mutans, both antiseptics at all concentrations required a longer exposure time. We found that a clinically-used 1% of polyhexamethylene guanidine phosphate concentration did not have activity against L. acidophilus. High RF of polyhexamethylene guanidine phosphate and retention of bactericidal effects, even at 0.05%, support the use of polyhexamethylene guanidine phosphate as a biocide with sufficient anti-microbial activity against periopathogens. Polyhexamethylene guanidine phosphate displayed bactericidal activity against periopathogens and S. mutans and could potentially be applied in the management of oral

  9. Chemical equilibrium in the GaP-HCl and InP-HCl systems

    International Nuclear Information System (INIS)

    Goliusov, V.A.; Voronin, V.A.; Chuchmarev, S.K.

    1983-01-01

    Chemical equilibrium in the GaP-HCl and InP-HCl systems is investigated experimentally, polynomial dependence of the total pressure on temperature (800-1100 K) and hydrochloric aci concntration under the experimental conditions is obtained. The technique for equilibrium calculation in hydrogencontaining chemical systems based on the tensimetric investigation results is suggested. The equilibrium gas phase composition in the GaP(InP)-HCl systems and self consistent, within the framework of the designed equilibrium model thermodynamic characteristics are determined. The effectiveness of gas-phase indium- and gallium phosphides precipitation in the GaP(InP)-HCl systems is calculated

  10. Determination of pyrophosphate and sulfate using polyhexamethylene guanidine hydrochloride-stabilized silver nanoparticles.

    Science.gov (United States)

    Terenteva, E A; Apyari, V V; Dmitrienko, S G; Garshev, A V; Volkov, P A; Zolotov, Yu A

    2018-04-01

    Positively charged polyhexamethylene guanidine hydrochloride-stabilized silver nanoparticles (PHMG-AgNPs) were prepared and applied as a colorimetric probe for single-step determination of pyrophosphate and sulfate. The approach is based on the nanoparticles aggregation leading to change in their absorption spectra and color of the solution. Due to both electrostatic and steric stabilization these nanoparticles show decreased sensitivity relatively to many common anions, which allows for simple and rapid direct single-step determination of pyrophosphate and sulfate. Effects of different factors (time of interaction, pH, concentrations of anions and the nanoparticles) on aggregation of PHMG-AgNPs and analytical performance of the procedure were investigated. The method allows for the determination of pyrophosphate and sulfate in the range of 0.16-2μgmL -1 and 20-80μgmL -1 with RSD of 2-5%, respectively. The analysis can be performed using either spectrophotometry or naked-eye detection. Practical application of the method was shown by the example of pyrophosphate determination in baking powder sample. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Integration of Bromine and Cyanogen Bromide Generators for the Continuous-Flow Synthesis of Cyclic Guanidines.

    Science.gov (United States)

    Glotz, Gabriel; Lebl, René; Dallinger, Doris; Kappe, C Oliver

    2017-10-23

    A continuous-flow process for the in situ on-demand generation of cyanogen bromide (BrCN) from bromine and potassium cyanide that makes use of membrane-separation technology is described. In order to circumvent the handling, storage, and transportation of elemental bromine, a continuous bromine generator using bromate-bromide synproportionation can optionally be attached upstream. Monitoring and quantification of BrCN generation was enabled through the implementation of in-line FTIR technology. With the Br 2 and BrCN generators connected in series, 0.2 mmol BrCN per minute was produced, which corresponds to a 0.8 m solution of BrCN in dichloromethane. The modular Br 2 /BrCN generator was employed for the synthesis of a diverse set of biologically relevant five- and six-membered cyclic amidines and guanidines. The set-up can either be operated in a fully integrated continuous format or, where reactive crystallization is beneficial, in semi-batch mode. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Refinement of crystal structures of CaHCl, SrHCl, BaHCl, BaHBr, and BaHI

    International Nuclear Information System (INIS)

    Beck, H.P.; Limmer, A.

    1983-01-01

    The structures of CaHCl, SrHCl, BaHBr, BaHCl, and BaHI have been refined using single crystal data. The comparison of the parameters with the corresponding data of isotypic fluorohalide compounds gives a valuable insight into the bonding interactions in this structure type. (author)

  13. Refinement of crystal structures of CaHCl, SrHCl, BaHCl, BaHBr, and BaHI

    Energy Technology Data Exchange (ETDEWEB)

    Beck, H.P.; Limmer, A. (Erlangen-Nuernberg Univ., Erlangen (Germany, F.R.). Inst. fuer Anorganische Chemie)

    1983-07-01

    The structures of CaHCl, SrHCl, BaHBr, BaHCl, and BaHI have been refined using single crystal data. The comparison of the parameters with the corresponding data of isotypic fluorohalide compounds gives a valuable insight into the bonding interactions in this structure type.

  14. Antioxidant assessment on promethazinr HCl decomposition using ...

    African Journals Online (AJOL)

    The objective of this study was to investigate the effect of different sodium metabisulfite (SMBS) concentrations under a variety of ICH recommended test conditions. An attempt was made to test the feasibility of increasing shelf life when stored under different conditions. The promethazine hydrochloride (HCL) sample ...

  15. Optimal control of vibrational transitions of HCl

    Indian Academy of Sciences (India)

    Control of fundamental and overtone transitions of a vibration are studied for the diatomic molecule, HCl. Specifically, the results of the effect of variation of the penalty factor on the physical attributes of the system (i.e., probabilities) and pulse (i.e., amplitudes) considering three different pulse durations for each value of the ...

  16. Optimal control of vibrational transitions of HCl

    Indian Academy of Sciences (India)

    2016-09-07

    Sep 7, 2016 ... and making, occur in ultrafast time-scale. The control of energy flow in a relatively short time-scale (∼10 fs), in a nuclear ... general motivation to study HCl. ...... ics in science and engineering (Academic Press, New York,.

  17. Effects of polyhexamethylene guanidine phosphate on human gingival fibroblasts.

    Science.gov (United States)

    Vitt, Anton; Slizen, Veronica; Boström, Elisabeth A; Yucel-Lindberg, Tülay; Kats, Anna; Sugars, Rachael V; Gustafsson, Anders; Buhlin, Kåre

    2017-10-01

    Polyhexamethylene guanidine phosphate (PHMG-P) was compared to chlorhexidine (CHX) in order to determine potential cytotoxic and immune-modulatory effects on human gingival fibroblasts. Cytotoxic effects of PHMG-P and CHX on human gingival fibroblasts were assessed using cell viability assay at various time points and concentrations. The effects of PHMG-P and CHX on the secretion of prostaglandin (PG) E 2 , interleukin (IL)-6, IL-8 and matrix metalloproteinase (MMP)-1 by non-stimulated or IL-1β stimulated fibroblasts were evaluated by enzyme-linked immunosorbent assays. PHMG-P concentration 0.00009% led to the total loss of fibroblast viability within 24 h, whereas inhibition of fibroblast viability by CHX occurred at significantly higher concentrations of 0.0009% (p PHMG-P led to loss of fibroblast viability after 5 min, whilst cells exposed to 0.005% CHX survived 30 min of treatment (p PHMG-P or CHX at concentrations of 0.000045 or 0.0.00009% resulted in significantly decreased PGE 2 , IL-6, IL-8 and MMP-1 levels. PHMG-P or CHX alone did not affect the baseline secretion of PGE 2 , IL-6, IL-8 or MMP-1 by gingival fibroblasts. Cytotoxic effects on gingival fibroblasts were triggered by both PHMG-P and CHX at concentrations below those used in clinical practice. The tested antiseptics did not cause inflammation and reduced IL-1β-induced secretion of inflammatory mediators and collagenase by gingival fibroblasts, which suggests anti-inflammatory properties.

  18. Separating NaCl and AlCl3·6H2O Crystals from Acidic Solution Assisted by the Non-Equilibrium Phase Diagram of AlCl3-NaCl-H2O(-HCl Salt-Water System at 353.15 K

    Directory of Open Access Journals (Sweden)

    Huaigang Cheng

    2017-08-01

    Full Text Available Extracting AlCl3·6H2O from acid leaching solution through crystallization is one of the key processes to extracting aluminum from fly ash, coal gangue and other industrial solid wastes. However, the obtained products usually have low purity and a key problem is the lack of accurate data for phase equilibrium. This paper presented the non-equilibrium phase diagrams of AlCl3-NaCl-H2O (HCl salt-water systems under continuous heating and evaporation conditions, which were the main components of the acid leaching solution obtained through a sodium-assisted activation hydrochloric acid leaching process. The ternary system was of a simple eutonic type under different acidities. There were three crystalline regions; the crystalline regions of AlCl3·6H2O, NaCl and the mixture AlCl3·6H2O/NaCl, respectively. The phase diagram was used to optimize the crystallization process of AlCl3·6H2O and NaCl. A process was designed to evaporate and remove NaCl at the first stage of the evaporation process, and then continue to evaporate and crystallize AlCl3·6H2O after solid-liquid separation. The purities of the final salt products were 99.12% for NaCl and up to 97.35% for AlCl3·6H2O, respectively.

  19. Protection of HCl dew point corrosion in municipal incinerators

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, S.; Tsuruta, T.; Maeda, N.

    1976-12-01

    HCl dew point corrosion is often observed on the components of municipal incinerators used for burning wastes which contain polyvinyl chloride. In order to solve the problem, the relation between concentrations of gaseous HCl and the corresponding dew points as well as concentrations of condensed HCl, was investigated. A series of HCl dipping tests for the materials concerned was performed and the dip test results were compared with in-plant tests. As a result it was concluded that HCl dew point corrosion can be reliably predicted from measurements of HCl concentrations in the water and in the gas and the partial pressure of the saturated steam at the dew point.

  20. Palladium-Catalyzed C-H Functionalization Using Guanidine as a Directing Group: Ortho Arylation and Olefination of Arylguanidines

    Science.gov (United States)

    Shao, Jiaan; Chen, Wenteng; Giulianotti, Marc A.; Houghten, Richard A.; Yu, Yongping

    2012-01-01

    Palladium-catalyzed C-H functionalization using guanidine as the directing group was achieved under mild reaction conditions. Various guanidine derivatives were produced in moderate to good yields by using simple unactivated arenes or ethyl acrylate as the source of arylation or olefination respectively. PMID:23095022

  1. Development of tartaric acid derived chiral guanidines and their application to catalytic enantioselective α-hydroxylation of β-dicarbonyl compounds.

    Science.gov (United States)

    Zou, Liwei; Wang, Baomin; Mu, Hongfang; Zhang, Huanrui; Song, Yuming; Qu, Jingping

    2013-06-21

    A novel library of chiral guanidines featuring a tartaric acid skeleton was developed from diethyl l-tartrate. These guanidines are easily accessed with tunable steric and electronic properties. The utilities of the guanidines were highlighted by their ability to catalyze the α-hydroxylation of β-ketoesters and β-diketones with remarkable efficiency and excellent enantioselectivity.

  2. On the guanidine hydrochloride method for determination of oxygen-18 content in orthophosphate

    International Nuclear Information System (INIS)

    Li Wenjun; Gu Zhennan

    1985-01-01

    The guanidine hydrochloride method is an accurate and simple procedure for oxygen-18 determination in KH 2 PO 4 and Ba 3 (PO 4 ) 2 . The method is based on heating the samples with guanidine hydrochloride at 300 deg C. Two Oxygen atoms per molecule of KH 2 PO 4 or Ba 3 (PO 4 ) 2 are converted into CO 2 which is then analysed by a mass spectrometer of model MAT-CH5. Only 5 mg of KH 2 PO 4 or Ba 3 (PO 4 ) 2 is required for each determination and reproducibility of assays is better than +-1%. (Author)

  3. Degradation of surfactant-modified montmorillonites in HCl

    International Nuclear Information System (INIS)

    Madejová, Jana; Pálková, Helena; Jankovič, Ľuboš

    2012-01-01

    The effect of surfactant size on the extent of montmorillonites decomposition in HCl was investigated. Na-SAz montmorillonite and tetraalkylammonium salts of alkyl-chains length increasing from methyl- Me 4 N to pentyl- Pe 4 N were used for organo-montmorillonites preparation. Decreasing intensity of d 001 diffraction proved destruction of montmorillonite structure connected with gradual surfactant release. A shift of the SiO stretching band to 1097 cm −1 confirmed formation of amorphous silica phase. A new band near 7315 cm −1 corresponding to SiOH overtone revealed creation of protonated silica. This band was observed in the spectra of all acid-treated samples, also in those with minor decomposition of the structure. The size of the cations significantly affected decomposition of montmorillonites in HCl. The less stable were Na-SAz and Me 4 N-SAz in which the content of octahedral atoms dropped to ∼5% of their original values upon 8 h treatments. Et 4 N-SAz and Pr 4 N-SAz were slightly more resistant mainly at short times. Bu 4 N-SAz and Pe 4 N-SAz showed the least structural modifications, only 50% and 35% of octahedral atoms, respectively, were released into solution within 8 h treatments. This observation proves that bulky alkylammonium cations covering the inner and outer surfaces of montmorillonite prevent effectively the access of protons to the layers protecting the mineral from degradation in the acid. - Highlights: ► Hybrid materials were prepared from montmorillonite and alkylammonium cations with short alkyl chains. ► The effect of surfactant on organo-montmorillonites dissolution in HCl was studied. ► With increasing size of cation the extent of montmorillonite decomposition decreased. ► Bulky surfactants prevent the access of protons to the layers and thus protect montmorillonite from degradation.

  4. Kinetika Hidrolisis Pati Biji Nangka (Artocarpus heterophyllus Menggunakan Katalisator Asam Klorida (HCl

    Directory of Open Access Journals (Sweden)

    Sri Endang

    2014-07-01

    Full Text Available The research of kinetic hydrolysis from the starch of jackfruit seed (Artocarpus heterophyllus used clorid acid catalyst (HCl aims to know the influence of variation of concentration HCl catalyst which give the maximum result of hydrolysis of the starch of jackfruit seed, determining the optimum concentration of HCl catalyst that produces the maximum value of the reaction rate constants, and determine the value of the reaction rate constant of hydrolysis the starch of jackfruit seed using catalyst. The method of this research has done in two stages that are the determination of the optimum catalyst concentration of HCl hydrolysis reaction of the starch of jackfruit seed using various concentration of catalyst HCl 0,5 M; 1,0 M; 1,5 M; 2,0 M and 2,5 M at the optimum temperature and stirring time (90oC during 70 minutes. Hydrolysis followed by neutralization process using sodium hydroxide solution and evaporated to get the form of glucose concentrated, that glucose is analyzed by qualitative and quantitative with Benedict experiment and fenol sulphate acid method, based on maximum degree of glucose which is gotten from the result of hydrolysis the starch of jackfruit seed variation concentration oh HCl is in HCl 1,5 M concentration with degree of glucose (% weight is 7,54% with percentage of starch conversion is 83,21%. Second step is determining the value of hydrolysis constant rate reaction which use time variation (30, 40,50, 60 and 70 minutes in 70 minutes optimum operation condition, 90oC te mperature and concentration catalyst of HCl 1,5 M. Based on statistic calculation date of ANOVA is gained F hitung < F tabel so Ho receive and reject HI  which shows that there is not influence catalyst variation concentration of HCl to the result of hydrolysis the starch of jackfruit seed which is gained. The result of the research shows that hydrolysis of kinetic of the starch of jackfruit seeduse HCl catalyst is reaction of the first apparent orde with

  5. Optical sensing of HCl with phenol red doped sol-gels

    International Nuclear Information System (INIS)

    Wang Enju; Chow, Kwok-Fan; Wang Wenqun; Wong, Crystal; Yee, Cynthia; Persad, Alvin; Mann, Jonathan; Bocarsly, Andrew

    2005-01-01

    A dye doped sol-gel for the sensing of hydrochloric acid in solution and/or gaseous phase is described. The sol-gel is obtained by acidic hydrolysis of tetraethoxysilane (TEOS) and phenyltriethoxysilane (Ph-TriEOS) in the presence of phenol red (PR) and further spin-coating onto glass slides. The sensitive response is based on an increase of the absorption band at 510 nm of phenol red entrapped in the sol-gel casting when exposed to HCl solution or gas, due to protonation of the dye. The detection limit of the sol-gel response to moisturized gaseous HCl is below 12 ppm, and its response to HCl in solution falls in the range of 0.01-6 M. The sol-gel coating has a response time of less than 40 s in steady-state, and life-time of more than a year. Weak acids such as acetic acid, benzoic acid, salicylate acid, citrate acid, and carbonic acid do not interfere the response. The responses in acid solutions are completely reversible. In the gaseous phase, response of HCl appears to be moisture sensitive

  6. Optical sensing of HCl with phenol red doped sol-gels

    Energy Technology Data Exchange (ETDEWEB)

    Wang Enju [Department of Chemistry, St. John' s University, 8000 Utopia Parkway, Jamaica, NY 11439 (United States)]. E-mail: wange@stjohns.edu; Chow, Kwok-Fan [Department of Chemistry, St. John' s University, 8000 Utopia Parkway, Jamaica, NY 11439 (United States); Wang Wenqun [Department of Chemistry, St. John' s University, 8000 Utopia Parkway, Jamaica, NY 11439 (United States); Wong, Crystal [Department of Chemistry, St. John' s University, 8000 Utopia Parkway, Jamaica, NY 11439 (United States); Yee, Cynthia [Department of Chemistry, St. John' s University, 8000 Utopia Parkway, Jamaica, NY 11439 (United States); Persad, Alvin [Department of Chemistry, St. John' s University, 8000 Utopia Parkway, Jamaica, NY 11439 (United States); Mann, Jonathan [Department of Chemistry, Princeton University, Princeton, NJ 08540 (United States); Bocarsly, Andrew [Department of Chemistry, Princeton University, Princeton, NJ 08540 (United States)

    2005-04-08

    A dye doped sol-gel for the sensing of hydrochloric acid in solution and/or gaseous phase is described. The sol-gel is obtained by acidic hydrolysis of tetraethoxysilane (TEOS) and phenyltriethoxysilane (Ph-TriEOS) in the presence of phenol red (PR) and further spin-coating onto glass slides. The sensitive response is based on an increase of the absorption band at 510 nm of phenol red entrapped in the sol-gel casting when exposed to HCl solution or gas, due to protonation of the dye. The detection limit of the sol-gel response to moisturized gaseous HCl is below 12 ppm, and its response to HCl in solution falls in the range of 0.01-6 M. The sol-gel coating has a response time of less than 40 s in steady-state, and life-time of more than a year. Weak acids such as acetic acid, benzoic acid, salicylate acid, citrate acid, and carbonic acid do not interfere the response. The responses in acid solutions are completely reversible. In the gaseous phase, response of HCl appears to be moisture sensitive.

  7. Synthesis, characterization, and thermal properties of homoleptic rare-earth guanidinates: promising precursors for MOCVD and ALD of rare-earth oxide thin films.

    Science.gov (United States)

    Milanov, Andrian P; Fischer, Roland A; Devi, Anjana

    2008-12-01

    Eight novel homoleptic tris-guanidinato complexes M[(N(i)Pr)(2)CNR(2)](3) [M = Y (a), Gd (b), Dy (c) and R = Me (1), Et (2), (i)Pr (3)] have been synthesized and characterized by NMR, CHN-analysis, mass spectrometry and infrared spectroscopy. Single crystal structure analysis revealed that all the compounds are monomers with the rare-earth metal center coordinated to six nitrogen atoms of the three chelating guanidinato ligands in a distorted trigonal prism geometry. With the use of TGA/DTA and isothermal TGA analysis, the thermal characteristics of all the complexes were studied in detail to evaluate their suitability as precursors for thin film deposition by MOCVD and ALD. The (i)Pr-Me(2)N-guanidinates of Y, Gd and Dy (1a-c) showed excellent thermal characteristics in terms of thermal stability and volatility. Additionally, the thermal stability of the (i)Pr-Me(2)N-guanidinates of Y and Dy (1a, c) in solution was investigated by carrying out NMR decomposition experiments and both the compounds were found to be remarkably stable. All these studies indicate that (i)Pr-Me(2)N-guanidinates of Y, Gd and Dy (1a-c) have the prerequisites for MOCVD and ALD applications which were confirmed by the successful deposition of Gd(2)O(3) and Dy(2)O(3) thin films on Si(100) substrates. The MOCVD grown films of Gd(2)O(3) and Dy(2)O(3) were highly oriented in the cubic phase, while the ALD grown films were amorphous.

  8. Formulation of Bilayer Benzydamine HCl Patch Targeted For Gingivitis

    Directory of Open Access Journals (Sweden)

    Piyush Sanghai

    2016-01-01

    Full Text Available In the present study bilayer patch of benzydamine HCl was developed using solvent casting method. Different substrates were attempted like Petri dish, glass-and-ring, and teflon-and-ring for selection of the proper option to formulate patch that should give easily peelable film with adequate mechanical properties. HPMC E15 LV was used in different concentrations for obtaining proper viscosity of solution for pouring on to surface and ring, that it should not leak from ring. The second layer was optimized by using different polymer like eudragit RSPO, eudragit RSPO + EC, and eudragit NE30 D for efficient layer bonding. The minimum release from backing membrane was established by diffusion study as compared to from drug loaded layer. The optimized batches were evaluated for folding endurance, weight variation, thickness, drug content, drug release, tensile strength, layer separation, mucoadhesion, moisture uptake, and layer bonding. The novel gingival patch of benzydamine HCl developed would be beneficial in optimizing the therapy.

  9. Very Strong Organosuperbases Formed by Combining Imidazole and Guanidine Bases: Synthesis, Structure, and Basicity

    Czech Academy of Sciences Publication Activity Database

    Vazdar, Katarina; Kunetskiy, Roman Alexejevič; Saame, J.; Kaupmees, K.; Leito, I.; Jahn, Ullrich

    2014-01-01

    Roč. 53, č. 5 (2014), s. 1435-1438 ISSN 1433-7851 Institutional support: RVO:61388963 Keywords : guanidine * organosuperbases * synthetic methods * basicity * UV/Vis spectroscopy Subject RIV: CC - Organic Chemistry Impact factor: 11.261, year: 2014

  10. Search for chemical separations of the element 106 homologues in HF and HF-HCl media

    International Nuclear Information System (INIS)

    Trubert, D.; Monroy-Guzman, F.; Hussonnois, M.; Brillard, L.; Le Naour, C.; Constantinescu, O.

    1996-01-01

    In order to study the chemical properties of element 263 106 in aqueous media, fast, efficient and reproducible chromatographic separations were tested on its assumed homologous: Mo, W and U. Corroborative static and dynamic off-line experiments have shown that after fixation of these three elements on anion-exchange resin in HF medium, selective elution could be achieved by using suitable concentration of HCl - HF and HCl solutions. Separations of short-lived W isotopes, produced through heavy ion irradiation were also performed on-line. (author). 27 refs., 14 figs

  11. Nickel and platinum in high-temperature H2O + HCl fluids: Implications for hydrothermal mobilization

    Science.gov (United States)

    Scholten, Lea; Watenphul, Anke; Beermann, Oliver; Testemale, Denis; Ames, Doreen; Schmidt, Christian

    2018-03-01

    The dissolution of NiS and NiAs (nickeline) in 0.1 and 1 molal HCl at 400 °C, 80 MPa, and of PtAs2 (sperrylite) and Pt metal in 1 and 6.86 molal HCl at 500 °C, 80 MPa was studied in-situ using synchrotron radiation X-ray fluorescence and absorption spectroscopy. The Pt concentration in the fluid averaged 8 · 10-5 molal (12.8 ppm) during dissolution of Pt metal in 6.86 molal HCl, and was below the minimum detection limit (mdl; 2.6 · 10-5 molal) in all other experiments. Dissolution of NiS was congruent or nearly congruent. Equilibrium was attained rapidly in about 250 min at an initial HCl concentration of 1 molal HCl, and in about 500 min at 0.1 molal HCl. Addition of HCl resulted in a large increase in the Ni solubility from 7.2 · 10-3 molal Ni (423 ppm) at 0.1 molal HCl to 8.72 · 10-2 molal Ni (4959 ppm) at 1 molal HCl. Dissolution of NiAs in 0.1 and 1 molal HCl was incongruent. A steady state was not reached even at a run duration of more than 16 h, and the maximum recorded Ni concentrations in the fluid were much lower than the Ni solubility in the corresponding experiments with NiS at the same HCl molality. Measured K-edge XANES spectra in comparison with literature data indicated that arsenic in the fluid was present as As(V) and that nickel complexed with Cl and H2O as tetrahedral [NiCl2(H2O)2]0 and [NiCl3(H2O)]- and octahedral [NiCl2(H2O)4]0 species. In addition, Raman spectra of H2O + NiCl2 and H2O + NiCl2 + HCl solutions and of H2O + HCl fluids reacted with NiS crystals were acquired at temperatures (T) up to 600 °C and pressures (P) up to 1.15 GPa. All spectra at T ≥ 300 °C and P conflict with the information from published XAS data. The results of this study demonstrate that nickel is readily mobilized by acidic chloridic hydrothermal fluids, but platinum remains practically immobile in such fluids at any HCl concentration that is conceivable to occur in nature. Therefore, the enrichment of Pt relative to Ni in footwall-type deposits in the

  12. Investigation of strontium sorption on Kula volcanites treated with HCl

    International Nuclear Information System (INIS)

    Kuetahyali, C.; Cetinkaya, B.; Acar, M. B.; Isik, N. O.; Cireli, I.

    2009-01-01

    In planning the disposal of radioactive waste in a deep geologic repository, consideration must be given to the ways in which radionuclides might leave the repository and migrate through the geosphere. In performance assessment studies the uptake of the radioactive elements by rock formations play an important role in retarding their aqueous phase migration. Sorption studies of radionuclides have been conducted to obtain data on the distribution coefficient (K d ) that is as an input parameter in the performance assessment of the geological disposal of radioactive wastes. In many studies, the sorption experiments employed natural soils and rocks as sorbents. Adsorption experiments were studied in a batch adsorption system using Sr(NO 3 ) 2 (Merck) solution. Strontium sorption on Kula Volcanites treated with HCl was investigated. Central Composite Design Method was used in the experiments. Sr adsorption was studied as a function of pH, contact time, concentration of adsorbate, and temperature.

  13. Chromatographic methods for the simultaneous determination of binary mixture of Saxagliptin HCl and Metformin HCl

    Directory of Open Access Journals (Sweden)

    Hanan A. Merey

    2017-12-01

    Full Text Available Two chromatographic methods were suggested for the simultaneous determination of a binary mixture containing Saxagliptin HCl (SAG and Metformin HCl (MET. First method was RP-HPLC method. Chromatographic separation was done on Kinetex™ column–C18 (4.6 × 150 mm, 2.6 µm using mobile phase consisted of acetonitrile:phosphate buffer pH = 4.5 ± 0.1 adjusted with orthophosphoric acid (13:87, v/v. Isocratic elution at a flow rate 1.5 mL/min and UV detection at 220.0 nm was performed. Second method was spectro-densitometric method. Chromatographic separation was done on precoated silica gel aluminium plates 60 F254 as a stationary phase and developing system consisting of chloroform:methanol:formic acid (80:20:0.3, by volume. The density of the separated bands was measured by UV detector at 210.0 nm. The proposed methods were validated as per the ICH guidelines parameters like Linearity, precision, accuracy, selectivity, limit of detection and limit of quantitation. Statistical comparison was done between the obtained results and those obtained by the reported methods, showing no significant difference with respect to accuracy and precision. Keywords: Saxagliptin HCl, Metformin HCl, RP-HPLC, TLC

  14. The Effectiveness of HCl and HF Cleaning of Si0.85Ge0.15 Surface

    International Nuclear Information System (INIS)

    Sun, Y

    2008-01-01

    The cleaning of Si 0.85 Ge 0.15 surfaces using HCl and HF solutions is studied using synchrotron radiation photoelectron spectroscopy. The HF solution is found to be effective in removing both the Si oxide and the Ge oxide while the HCl solution can only remove part of the Ge oxide. For samples treated with HF, four spectral components are needed to fit the Ge 3d photoemission spectra. One is the bulk component and the other three are attributed to the surface Ge atoms with mono-hydride, di-hydride and tri-hydride terminations, respectively

  15. Adverse health effects of humidifier disinfectants in Korea: lung toxicity of polyhexamethylene guanidine phosphate.

    Science.gov (United States)

    Kim, Ha-Ryong; Hwang, Gi-Wook; Naganuma, Akira; Chung, Kyu-Hyuck

    2016-01-01

    Exposure to humidifier disinfectants was identified in 2011 as the potential cause of an outbreak of lung disease in Korea. It is estimated that over 8 million people have been exposed to humidifier disinfectants-chemicals added to the water used in humidifiers to prevent the growth of microorganisms-since their commercial introduction. The primary component of humidifier disinfectant products involved was polyhexamethylene guanidine phosphate (PHMG-P), a guanidine-based antimicrobial agent. Lesions observed in the lungs of patients were similar to those observed in laboratory animals exposed to PHMG-P. In this review, we outline the physicochemical and toxicological properties of PHMG-P, and introduce a putative mechanism for its lung toxicity based in large part on research findings to date.

  16. Synthesis of zirconium guanidinate complexes and the formation of zirconium carbonitride via low pressure CVD

    NARCIS (Netherlands)

    Potts, S.E.; Carmalt, C.J.; Blackman, C.S.; Abou-Chabine, F.; Pugh, D.; Davies, H.O.

    2009-01-01

    Thin films of zirconium carbonitride have been deposited on glass at 600 °C from two novel guanidinate precursors: [ZrCp'{¿2-(iPrN)2CNMe2}2Cl] (1) and [ZrCp'2{¿2-(iPrN)2CNMe2}Cl] (2) (Cp' ) monomethylcyclopentadienyl). Both compounds 1 and 2 were structurally characterized by X-ray crystallography.

  17. Coordination chemistry of nickel(II) nitrate with superbasic guanidines studied by electrospray mass spectrometry

    Czech Academy of Sciences Publication Activity Database

    Glasovac, Z.; Štrukil, V.; Eckert-Maksič, M.; Schröder, Detlef; Schlangen, M.; Schwarz, H.

    2010-01-01

    Roč. 290, č. 1 (2010), s. 22-31 ISSN 1387-3806 R&D Projects: GA ČR GA203/08/1487 Grant - others: ERC (XE) HORIZOMS AdG226373 Institutional research plan: CEZ:AV0Z40550506 Keywords : electrospray ionization * guanidine * ion association * nickel(II) nitrate * solvation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.009, year: 2010

  18. Magnetic silica hybrids modified with guanidine containing co-polymers for drug delivery applications

    Energy Technology Data Exchange (ETDEWEB)

    Timin, Alexander S., E-mail: a_timin@mail.ru [Inorganic Chemistry Department, Ivanovo State University of Chemistry and Technology (ISUCT), 7, Sheremetevsky prosp., 153000 Ivanovo (Russian Federation); RASA Center in Tomsk, Tomsk Polytechnic University, 30, Lenin Avenue, 634500 Tomsk (Russian Federation); Khashirova, Svetlana Yu. [Kabardino-Balkar State University, ul. Chernyshevskogo 173, Nal' chik, 360004 Kabardino-Balkaria (Russian Federation); Rumyantsev, Evgeniy V.; Goncharenko, Alexander A. [Inorganic Chemistry Department, Ivanovo State University of Chemistry and Technology (ISUCT), 7, Sheremetevsky prosp., 153000 Ivanovo (Russian Federation)

    2016-07-01

    Guanidine containing co-polymers grafted onto silica nanoparticles to form core-shell structure were prepared by sol-gel method in the presence of γ-Fe{sub 2}O{sub 3} nanoparticles. The morphological features for uncoated and coated silica particles have been characterized with scanning electron microscopy. The results show that the polymer coated silicas exhibit spherical morphology with rough polymeric surface covered by γ-Fe{sub 2}O{sub 3} nanoparticles. The grafting amount of guanidine containing co-polymers evaluated by thermogravimetric analysis was in the range from 17 to 30%. Then, the drug loading properties and cumulative release of silica hybrids modified with guanidine containing co-polymers were evaluated using molsidomine as a model drug. It was shown that after polymer grafting the loading content of molsidomine could reach up to 3.42 ± 0.21 and 2.34 ± 0.14 mg/g respectively. The maximum drug release of molsidomine is achieved at pH 1.6 (approximately 71–75% release at 37 °C), whereas at pH 7.4 drug release is lower (50.4–59.6% release at 37 °C). These results have an important implication that our magneto-controlled silica hybrids modified with guanidine containing co-polymers are promising as drug carriers with controlled behaviour under influence of magnetic field. - Highlights: • Polymer coated silica hybrids containing γ-Fe{sub 2}O{sub 3} were prepared via sol–gel method. • Polymer grafting influences pH-response and surface properties of final products. • Molsidomine as a model drug was effectively loaded into polymer coated silicas. • The drug loading depends on the nature of grafted polymer and its content.

  19. Guanidine hydrochloride embedded polyurethanes as antimicrobial and absorptive wound dressing membranes with promising cytocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Sahraro, Maryam; Yeganeh, Hamid, E-mail: h.yeganeh@ippi.ac.ir; Sorayya, Marziyeh

    2016-02-01

    Preparation and assessments of novel absorptive wound dressing materials with efficient antimicrobial activity as well as very good cytocompatibility were described in this work. An amine terminated poly(hexamethylene guanidine hydrochloride) was prepared and used as curing agent of different epoxy-terminated polyurethane prepolymers. The structures of prepared materials were elucidated by evaluation of their {sup 1}H NMR and FTIR spectra. The recorded tensile strength of membranes confirmed the excellent dimensional stability of the film type dressings even at fully hydrated conditions. Therefore, these dressings could protect the wound bed from external forces during the healing period. The structurally optimized dressing membranes could preserve the desired moist environment over the wounded area, as a result of their balanced equilibrium, water absorption and water vapor transmission rate. Therefore, a very good condition for stimulation of self-healing of wound bed was attained. Also, owing to the presence of guanidine hydrochloride moieties embedded into the structure of dressings, efficient antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans were detected. In vitro cytotoxicity assay of the prepared dressings revealed cytocompatibility of these materials against fibroblast cells. Therefore, they could support cell growth and proliferation at the wounded area. - Highlights: • New polyurethane wound dressings with guanidine hydrochloride based antimicrobials • Maintaining moist and warm wound environment for accelerating healing • Proper tensile strength of dressings even at fully hydrated state • Excellent biocompatibility index due to proper selection of starting materials.

  20. Densities and apparent molar volumes of atmospherically important electrolyte solutions. 1. The solutes H2SO4, HNO3, HCl, Na2SO4, NaNO3, NaCl, (NH4)2SO4, NH4NO3, and NH4Cl from 0 to 50 °C, including extrapolations to very low temperature and to the pure liquid state, and NaHSO4, NaOH, and NH3 at 25 °C.

    Science.gov (United States)

    Clegg, S L; Wexler, A S

    2011-04-21

    Calculations of the size and density of atmospheric aerosols are complicated by the fact that they can exist at concentrations highly supersaturated with respect to dissolved salts and supercooled with respect to ice. Densities and apparent molar volumes of solutes in aqueous solutions containing the solutes H(2)SO(4), HNO(3), HCl, Na(2)SO(4), NaNO(3), NaCl, (NH(4))(2)SO(4), NH(4)NO(3), and NH(4)Cl have been critically evaluated and represented using fitted equations from 0 to 50 °C or greater and from infinite dilution to concentrations saturated or supersaturated with respect to the dissolved salts. Using extrapolated densities of high-temperature solutions and melts, the relationship between density and concentration is extended to the hypothetical pure liquid solutes. Above a given reference concentration of a few mol kg(-1), it is observed that density increases almost linearly with decreasing temperature, and comparisons with available data below 0 °C suggest that the fitted equations for density can be extrapolated to very low temperatures. As concentration is decreased below the reference concentration, the variation of density with temperature tends to that of water (which decreases as temperature is reduced below 3.98 °C). In this region below the reference concentration, and below 0 °C, densities are calculated using extrapolated apparent molar volumes which are constrained to agree at the reference concentrations with an equation for the directly fitted density. Calculated volume properties agree well with available data at low temperatures, for both concentrated and dilute solutions. Comparisons are made with literature data for temperatures of maximum density. Apparent molar volumes at infinite dilution are consistent, on a single ion basis, to better than ±0.1 cm(3) mol(-1) from 0 to 50 °C. Volume properties of aqueous NaHSO(4), NaOH, and NH(3) have also been evaluated, at 25 °C only. In part 2 of this work (ref 1 ) an ion interaction (Pitzer

  1. Kinetics of acid leaching of ilmenite decomposed by KOH part 1: decomposition by KOH and leaching by HCl

    International Nuclear Information System (INIS)

    Nayl, A.A; Aly, H.F.

    2010-01-01

    Decomposition of ilmenite by KOH solutions, to convert titanium to potassium titanate, was first studied . This was followed by leaching titanium from the ilmenite paste using HCl solutions in the temperature range 50-150 degree C for different periods up to 3 hr. The significant factors affecting the leaching process were studied. The experimental data of the decomposition rate of ilmenite by KOH and of the formed KOH paste by HCl under the relevant operating variables were interpreted with the shrinking core model under chemically controlled process. The apparent activation energy for leaching of titanium in both cases bas been evaluated and discussed.

  2. Factor structure and reliability of the Arabic adaptation of the Hypomania Check List-32, second revision (HCL-32-R2).

    Science.gov (United States)

    Fornaro, Michele; Elassy, Mai; Mounir, Mina; Abd-Elmoneim, Noran; Ashour, Hala; Hamed, Rania; Al-Shehri, Abdullah; Bedir, Samir; Rashed, Ibrahem; Amer, Noha; Mohammed, Talal A; De Berardis, Domenico; Mazza, Monica; Pino, Mariachiara; Koshy, Ann Sarah; De Pasquale, Concetta; Okasha, Tarek; Angst, Jules

    2015-05-01

    To assess the psychometric properties of the Arabic adaptation of the Hypomania-Check-List 32-item, second revision (HCL-32-R2) for the detection of bipolarity in major depressive disorder (MDD) inpatients suffering a current major depressive episode (MDE). The "Bipolar Disorders: Improving Diagnosis, Guidance, and Education" Arabic module of the HCL-32-R2 was administered to mother-tongue Arabic MDE inpatients between March 2013 and October 2014. Diagnostic and Statistical Manual Fourth edition (DSM-IV) diagnoses were made adopting the mini-international neuropsychiatric interview, using bipolar disorder (BD) patients as controls. In our sample (n=500, of whom, BD-I=329; BD-II=70; MDD=101), using a cut-off of 17 allowed the HCL-32-R2 to discriminate DSM-IV-defined MDD patients between "true unipolar" (HCL-32-R2(-)) and "sub-threshold bipolar depression" (HCL-32-R2(+)) with sensitivity=82% and specificity=77%. Area under the curve was .883; positive and negative predictive values were 93.44% and 73.23% respectively. Owing to clinical interpretability considerations and consistency with previous adaptations of the HCL-32, a two-factor solution (F1="hyperactive/elated" vs. F2="irritable/distractible/impulsive") was preferred using exploratory and confirmatory factors analyses. Item n.33 ("I gamble more") and n.34 ("I eat more") introduced in the R2 version of the HCL-32 loaded onto F1, though very slightly. Cronbach's alphas were F1=.86 and F2=.60. No cross-validation with any additional validated screening tool. Inpatients only sample; recall bias; no systematic evaluation of eventual medical/psychiatric comorbidities, current/lifetime pharmacological history, or record of severity of current MDE. In our sample, the HCL-32 fairly discriminated between MDD and BD-I but not BD-II, therefore soliciting for replication studies for use in Arabic-speaking depressed inpatients. Copyright © 2015. Published by Elsevier Inc.

  3. Pharmaceutical Factors Affecting The Formulation Of Verapamil HCl ...

    African Journals Online (AJOL)

    Floating sustained release Verapamil HCl capsules were prepared using different polymers. Hydroxypropylmethyl cellulose 4000 and 50 (HPMC 4000 & HPMC 50), Carbopol 934, sodium alginate (Na alginate), carboxymethyl cellulose (CMC) and Pectin were used to study their effect on the release of Verapamil HCl from ...

  4. HCl co-production from CFC alternatives: Threat or opportunity?

    International Nuclear Information System (INIS)

    Mikulka, C.J.

    1990-01-01

    CFC production facilities have typically been located near CFC consumers and not necessarily near their feedstock sources. The co-production of HCl from these facilities has in the past been small and manageable by the CFC producers. Production of the CFC replacements, however, will result in larger quantities of HCl co-production at a scrutiny. Since new facilities are likely to be required for the replacements, there may be the opportunity to site facilities next to chlorocarbon suppliers who may be in a better position to take back the HCl co-product for reuse in their production facilities. This paper provides an overview of these issues as well as considers the implications of returning the HCl to the chlorocarbon supplier as well as viability of converting HCl back to chlorine

  5. HCl removal using cycled carbide slag from calcium looping cycles

    International Nuclear Information System (INIS)

    Xie, Xin; Li, Yingjie; Wang, Wenjing; Shi, Lei

    2014-01-01

    Highlights: • Cycled carbide slag from calcium looping cycles is used to remove HCl. • The optimum temperature for HCl removal of cycled carbide slag is 700 °C. • The presence of CO 2 restrains HCl removal of cycled carbide slag. • CO 2 capture conditions have important effects on HCl removal of cycled carbide slag. • HCl removal capacity of carbide slag drops with cycle number rising from 1 to 50. - Abstract: The carbide slag is an industrial waste from chlor-alkali plants, which can be used to capture CO 2 in the calcium looping cycles, i.e. carbonation/calcination cycles. In this work, the cycled carbide slag from the calcium looping cycles for CO 2 capture was proposed to remove HCl in the flue gas from the biomass-fired and RDFs-fired boilers. The effects of chlorination temperature, HCl concentration, particle size, presence of CO 2 , presence of O 2 , cycle number and CO 2 capture conditions in calcium looping cycles on the HCl removal behavior of the carbide slag experienced carbonation/calcination cycles were investigated in a triple fixed-bed reactor. The chlorination product of the cycled carbide slag from the calcium looping after absorbing HCl is not CaCl 2 but CaClOH. The optimum temperature for HCl removal of the cycled carbide slag from the carbonation/calcination cycles is 700 °C. The chlorination conversion of the cycled carbide slag increases with increasing the HCl concentration. The cycled carbide slag with larger particle size exhibits a lower chlorination conversion. The presence of CO 2 decreases the chlorination conversions of the cycled carbide slag and the presence of O 2 has a trifling impact. The chlorination conversion of the carbide slag experienced 1 carbonation/calcination cycle is higher than that of the uncycled calcined sorbent. As the number of carbonation/calcination cycles increases from 1 to 50, the chlorination conversion of carbide slag drops gradually. The high calcination temperature and high CO 2

  6. Studies on guanidinated N-3-aminopropyl methacrylamide-N-2-hydroxypropyl methacrylamide co-polymers as gene delivery carrier.

    Science.gov (United States)

    Qin, Zhu; Liu, Wei; Guo, Liang; Li, Xinsong

    2012-01-01

    Guanidinated N-3-aminopropyl methacrylamide (APMA)-N-2-hydroxypropyl methacrylamide (HPMA) co-polymers were prepared and evaluated to develop novel non-viral gene transfection carriers. The co-polymers were synthesized via radical co-polymerization of APMA and HPMA followed by total guanidination of amino groups, which employed guanidinated APMA (GPMA) for increasing cell-penetrating and HPMA as the positive shielding content. The molecular weight of guanidinated APMA-HPMA co-polymers (GPMA-HPMA) was determined by static light scattering. Furthermore, cytotoxicity and transfection experiments of GPMA-HPMA/pDNA complexes were conducted. A significant decrease of their parent cytotoxicity and an efficient transfection at relative low charge ratios were observed. The cellular distribution of most GPMA-HPMA/pDNA complexes was partially localized in the nucleus, as indicated by confocal laser scanning microscopy. The guanidination strategy employed may lead to non-viral gene delivery carriers that combine satisfactory transfection efficiency and cytotoxicity, which contribute to their cell-penetrating ability.

  7. Thermodynamics and Efficiency of a CuCl(aq)/HCl(aq) Electrolyzer

    International Nuclear Information System (INIS)

    Hall, Derek M.; Akinfiev, Nikolay N.; LaRow, Eric G.; Schatz, Richard S.; Lvov, Serguei N.

    2014-01-01

    The high ionic strength and complex speciation of the anolyte solution within the CuCl(aq)/HCl(aq) electrolytic cell have impeded predictions of the energy requirements for the cell's electrolytic reaction at 25 °C and 1 bar. After collecting experimental open circuit potential (OCP) data and comparing the values obtained with predictions from prospective thermodynamic models, an approach to predict thermodynamic values and the overall efficiency was formulated. The compositions of the experimental measurements ranged from 2-2.5 mol of CuCl(aq) with 8-9 mol of HCl(aq) per kilogram of water in anolyte solution and 8-9 mol of HCl(aq) per kilogram of water in catholyte solution. From the OCP data, it was found that activity coefficient and speciation effects were critical in predicting the Gibbs energy, entropy and thermodynamic (intrinsic maximum) efficiency of the electrolytic cell. At equilibrium, all thermodynamic functions of the anolyte redox reactions were the same after activity coefficients and speciation effects were taken into account. The electrochemical reactions’ Gibbs energy and entropy were found to be 9700 J/mol and 2.18 J/(mol K) at 25 °C and 1 bar, which indicated that the reactions required a small amount of electrical and thermal energy to proceed. With thermodynamic values for the electrolytic reaction and experimental data from a CuCl(aq)/HCl(aq) electrolytic cell, the voltage, current, thermodynamic and overall efficiency were calculated. The overall efficiency ranged from 15 to 95% depending on the current density

  8. Ferrocene-based guanidine derivatives: in vitro antimicrobial, DNA binding and docking supported urease inhibition studies.

    Science.gov (United States)

    Gul, Rukhsana; Rauf, Muhammad Khawar; Badshah, Amin; Azam, Syed Sikander; Tahir, Muhammad Nawaz; Khan, Azim

    2014-10-06

    Some novel ferrocenyl guanidines 1-8 were synthesized and characterized by different spectroscopic methods, elemental analysis and single crystal X-rays diffraction techniques. The crystallographic studies revealed that the existence of the strong non-bonding interactions facilitate these molecules to interact with biological macro-molecules like DNA that described to inherit good biological activities. The DNA interaction studies carried out by cyclic voltammetry (CV) and UV-visible spectroscopy are in close agreement with the binding constants (K) (0.79-5.4) × 10(5) (CV) and (0.72-5.1) × 10(5) (UV-vis). The shift in peak potential, current and absorption maxima of the studied ferrocenyl guanidines in the presence of DNA revealed that CV coupled with UV-vis spectroscopy could provide an opportune to characterize metal-based compounds-DNA interaction mechanism, a prerequisite for the design of new anticancer agents and understanding the molecular basis of their action. The compounds 1-8 have been screened for their antibacterial, antifungal and urease inhibition potency. A concurrent in silico study has also been applied on ferrocene moiety impregnated guanidines 1-8 to identify most active compounds having for inhibiting the activity of urease (pdb id 3LA4). Most of the compounds were found as potent inhibitors of urease and the compound 1 was found to be the most active with an IC50 of 16.83 ± 0.03 μM. The docking scores are in close agreement with the in vitro obtained IC50 values of inhibitors 1-8. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  9. New Insights into Solid Form Stability and Hydrate Formation: o-Phenanthroline HCl and Neocuproine HCl

    Directory of Open Access Journals (Sweden)

    Doris E. Braun

    2017-12-01

    Full Text Available The moisture- and temperature dependent stabilities and interrelation pathways of the practically relevant solid forms of o-phenanthroline HCl (1 and neocuproine HCl (2 were investigated using thermal analytical techniques (HSM, DSC and TGA and gravimetric moisture sorption/desorption studies. The experimental stability data were correlated with the structural changes observed upon dehydration and the pairwise interaction and lattice energies calculated. For 1 the monohydrate was identified as the only stable form under conditions of RH typically found during production and storage, but at RH values >80% deliquescence occurs. The second compound, 2, forms an anhydrate and two different hydrates, mono- (2-Hy1 and trihydrate (2-Hy3. The 2-Hy1 structure was solved from SCXRD data and the anhydrate structure derived from a combination of PXRD and CSP. Depending on the environmental conditions (moisture either 2-Hy1 or 2-Hy3 is the most sable solid form of 2 at RT. The monohydrates 1-Hy1 and 2-Hy1 show a high enthalpic stabilization (≥20 kJ mol−1 relative to the anhydrates. The anhydrates are unstable at ambient conditions and readily transform to the monohydrates even in the presence of traces of moisture. This study demonstrates how the right combination of experiment and theory can unravel the properties and interconversion pathways of solid forms.

  10. Tetramethyl guanidine (TMG catalyzed synthesis of novel a -amino phosphonates by one-pot reaction

    Directory of Open Access Journals (Sweden)

    S. Annar

    2010-07-01

    Full Text Available An efficient method has been developed for the synthesis of a -amino phosphonates (4a-j by the three component one-pot reaction of equimolar quantities of 2-amino methyl furan (1, dimethyl / diethyl phosphite (2 and various aldehydes (3a-j in dry toluene at reflux conditions via Kabachnik – Fields reaction in high yields (70-80% in the presence of tetramethyl guanidine (TMG as catalyst. The TMG can be easily recovered from the reaction mixture after completion of the reaction and can be reused. Their antimicrobial activity has also been evaluated.

  11. EDTA and HCl leaching of calcareous and acidic soils polluted with potentially toxic metals: remediation efficiency and soil impact.

    Science.gov (United States)

    Udovic, Metka; Lestan, Domen

    2012-07-01

    The environmental risk of potentially toxic metals (PTMs) in soil can be diminished by their removal. Among the available remediation techniques, soil leaching with various solutions is one of the most effective but data about the impact on soil chemical and biological properties are still scarce. We studied the effect of two common leaching agents, hydrochloric acid (HCl) and a chelating agent (EDTA) on Pb, Zn, Cd removal and accessibility and on physico-chemical and biological properties in one calcareous, pH neutral soil and one non-calcareous acidic soil. EDTA was a more efficient leachant compared to HCl: up to 133-times lower chelant concentration was needed for the same percentage (35%) of Pb removal. EDTA and HCl concentrations with similar PTM removal efficiency decreased PTM accessibility in both soils but had different impacts on soil properties. As expected, HCl significantly dissolved carbonates from calcareous soil, while EDTA leaching increased the pH of the acidic soil. Enzyme activity assays showed that leaching with HCl had a distinctly negative impact on soil microbial and enzyme activity, while leaching with EDTA had less impact. Our results emphasize the importance of considering the ecological impact of remediation processes on soil in addition to the capacity for PTM removal. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Cytotoxicity and gene expression profiling of polyhexamethylene guanidine hydrochloride in human alveolar A549 cells.

    Science.gov (United States)

    Jung, Ha-Na; Zerin, Tamanna; Podder, Biswajit; Song, Ho-Yeon; Kim, Yong-Sik

    2014-06-01

    In Korea, lung disease of children and pregnant women associated with humidifier disinfectant use has become a major concern. A common sterilizer is polyhexamethylene guanidine (PHMG), a member of the guanidine family of antiseptics. This study was done to elucidate the putative cytotoxic effect of PHMG and the PHMG-mediated altered gene expression in human alveolar epithelial A549 cells in vitro. Cell viability analyses revealed the potent cytotoxicity of PHMG, with cell death evident at as low as 5 μg/mL. Death was dose- and time-dependent, and was associated with formation of intracellular reactive oxygen species, and apoptosis significantly, at even 2 μg/mL concentration. The gene expression profile in A549 cells following 24 h exposure to 5 μg/mL of PHMG was investigated using DNA microarray analysis. Changes in gene expression relevant to the progression of cell death included induction of genes related to apoptosis, autophagy, fibrosis, and cell cycle. However, the expressions of genes encoding antioxidant and detoxifying enzymes were down-regulated or not affected. The altered expression of selected genes was confirmed by quantitative reverse transcription-polymerase chain reaction and Western blot analyses. The collective data suggest that PHMG confers cellular toxicity through the generation of intracellular reactive oxygen species and alteration of gene expression. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Study of high-temperature multiplex HCl coherent anti-Stokes Raman spectroscopy spectra.

    Science.gov (United States)

    Singh, J P; Yueh, F Y; Kao, W; Cook, R L

    1993-02-20

    A feasibility study of temperature measurement with multiplex HCl coherent anti-Stokes Raman spectroscopy (CARS) is investigated. The HCl CARS spectra of a 100% HCl gas sample are recorded in a quartz sample cell placed in a furnace at 1 atm pressure and at different temperatures. The nonlinear susceptibility of HCl (chi(nr)(HCl)), which is measured with the present CARS experimental setup, is reported. The experimental spectra are fit by using a library of simulated HCl CARS spectra with a least-squares-fitting program to infer the temperature. The inferred temperatures from HCl CARS spectra are in agreement with thermocouple temperatures.

  14. Enhancement removal of tartrazine dye using HCl-doped polyaniline and TiO2-decorated PANI particles

    Science.gov (United States)

    Elsayed, M. A.; Gobara, Mohamed

    2016-08-01

    HCl-doped polyaniline (HCl-PANI) and titanium dioxide decorated with polyaniline (TiO2-decorated PANI) with different TiO2:PANI ratios were chemically prepared and utilized for the removal of tartrazine (TZ) dye from a synthetic aqueous solution. The mechanism of preparation of the sample suggested that aniline was adsorbed on the TiO2 surface before the polymerization process took place. Samples were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive x-ray spectroscopy and x-ray diffraction. The results showed that HCl-PANI and TiO2-decorated PANI have an amorphous structure. The thermal stability of the prepared samples was characterized using thermo-gravimetric (TG) analysis. HCl-PANI is stable up to 200 °C and the relative weight per cent of PANI in the TiO2-decorated PANI was 20, 25, 40 and 45%. The removal activity of TiO2-decorated PANI via TZ azo dye was investigated under UV light irradiations and compared with HCl-PANI and TiO2 particles. The results indicated the superiority of the TiO2-decorated PANI over pure HCl-PANI and TiO2. However, the excessive PANI percentage tends to form a relatively thick layer, and even aggregates on the surface of TiO2. This hinders the migration of excited electrons from the outer PANI layer to the inner TiO2 particles, which consequently leads to a decrease in the removal efficiency. A possible mechanism for the removal oxidative degradation is also mentioned.

  15. High-temperature chemistry of HCl and Cl2

    DEFF Research Database (Denmark)

    Pelucchi, Matteo; Frassoldati, Alessio; Faravelli, Tiziano

    2015-01-01

    The high temperature chlorine chemistry was updated and the inhibition mechanisms involving HCl and Cl2 were re-examined. The thermochemistry was obtained using the Active Thermochemical Tables (ATcT) approach, resulting in improved data for chlorine-containing species of interest. The HCl/Cl2....... The validation was carried out on selected experimental data from laminar flames, shock tubes and plug flow reactors. Systems containing Cl2 showed high sensitivity to Cl2 +M⇌Cl+Cl+M; the rate constant for this reaction has a significant uncertainty and there is a need for an accurate high...... chemistry discussed in the paper was based on reference and experimental measurements of rate constants available in the literature. By coupling the new HCl/Cl2 subset with the Politecnico di Milano (POLIMI) syngas mechanism a kinetic mechanism consisting of 25 species and 102 reactions was obtained...

  16. The dissociation mechanism and thermodynamic properties of HCl(aq) in hydrothermal fluids (to 700 °C, 60 kbar) by ab initio molecular dynamics simulations

    Science.gov (United States)

    Mei, Yuan; Liu, Weihua; Brugger, Joël; Sherman, David M.; Gale, Julian D.

    2018-04-01

    HCl is one of the most significant volatiles in the Earth's crust. It is well established that chloride activity and acidity (pH) play important roles in controlling the solubility of metals in aqueous hydrothermal fluids. Thus, quantifying the dissociation of HCl in aqueous solutions over a wide range of temperature and pressure is crucial for the understanding and numerical modeling of element mobility in hydrothermal fluids. Here we have conducted ab initio molecular dynamics (MD) simulations to investigate the mechanism of HCl(aq) dissociation and to calculate the thermodynamic properties for the dissociation reaction at 25-700 °C, 1 bar to 60 kbar, i.e. including high temperature and pressure conditions that are geologically important, but difficult to investigate via experiments. Our results predict that HCl(aq) tends to associate with increasing temperature, and dissociate with increasing pressure. In particular, HCl(aq) is highly dissociated at extremely high pressures, even at high temperatures (e.g., 60 kbar, 600-700 °C). At 25 °C, the calculated logKd values (6.79 ± 0.81) are close to the value (7.0) recommended by IUPAC (International Union of Pure and Applied Chemistry) and some previous experimental and theoretical studies (Simonson et al.., 1990; Sulpizi and Sprik, 2008, 2010). The MD simulations indicate full dissociation of HCl at low temperature; in contrast, some experiments were interpreted assuming significant association at high HCl concentrations (≥1 m HCltot) even at room T (logKd ∼0.7; e.g., Ruaya and Seward, 1987; Sretenskaya, 1992; review in Tagirov et al., 1997). This discrepancy is most likely the result of difficulties in the experimental determination of minor (if any) concentration of associated HCl(aq) under ambient conditions, and thus reflects differences in the activity models used for the interpretation of the experiments. With increasing temperature, the discrepancy between our MD results and previous experimental

  17. HERSCHEL/HIFI DISCOVERY OF HCL+ IN THE INTERSTELLAR MEDIUM

    International Nuclear Information System (INIS)

    De Luca, M.; Gerin, M.; Falgarone, E.; Gupta, H.; Drouin, B. J.; Pearson, J. C.; Neufeld, D.; Teyssier, D.; Lis, D. C.; Monje, R.; Phillips, T. G.; Goicoechea, J. R.; Godard, B.; Bell, T. A.; Coutens, A.

    2012-01-01

    The radical ion HCl + , a key intermediate in the chlorine chemistry of the interstellar gas, has been identified for the first time in the interstellar medium with the Herschel Space Observatory's Heterodyne Instrument for the Far-Infrared. The ground-state rotational transition of H 35 Cl + , 2 Π 3/2 J = 5/2-3/2, showing Λ-doubling and hyperfine structure, is detected in absorption toward the Galactic star-forming regions W31C (G10.6-0.4) and W49N. The complex interstellar absorption features are modeled by convolving in velocity space the opacity profiles of other molecular tracers toward the same sources with the fine and hyperfine structure of HCl + . This structure is derived from a combined analysis of optical data from the literature and new laboratory measurements of pure rotational transitions, reported in the accompanying Letter by Gupta et al. The models reproduce well the interstellar absorption, and the frequencies inferred from the astronomical observations are in exact agreement with those calculated using spectroscopic constants derived from the laboratory data. The detection of H 37 Cl + toward W31C, with a column density consistent with the expected 35 Cl/ 37 Cl isotopic ratio, provides additional evidence for the identification. A comparison with the chemically related molecules HCl and H 2 Cl + yields an abundance ratio of unity with both species (HCl + : H 2 Cl + : HCl ∼ 1). These observations also yield the unexpected result that HCl + accounts for 3%-5% of the gas-phase chlorine toward W49N and W31C, values several times larger than the maximum fraction (∼1%) predicted by chemical models.

  18. Determination of diethyl phthalate and polyhexamethylene guanidine in surrogate alcohol from Russia.

    Science.gov (United States)

    Monakhova, Yulia B; Kuballa, Thomas; Leitz, Jenny; Lachenmeier, Dirk W

    2011-01-01

    Analytical methods based on spectroscopic techniques were developed and validated for the determination of diethyl phthalate (DEP) and polyhexamethylene guanidine (PHMG), which may occur in unrecorded alcohol. Analysis for PHMG was based on UV-VIS spectrophotometry after derivatization with Eosin Y and (1)H NMR spectroscopy of the DMSO extract. Analysis of DEP was performed with direct UV-VIS and (1)H NMR methods. Multivariate curve resolution and spectra computation methods were used to confirm the presence of PHMG and DEP in the investigated beverages. Of 22 analysed alcohol samples, two contained DEP or PHMG. (1)H NMR analysis also revealed the presence of signals of hawthorn extract in three medicinal alcohols used as surrogate alcohol. The simple and cheap UV-VIS methods can be used for rapid screening of surrogate alcohol samples for impurities, while (1)H NMR is recommended for specific confirmatory analysis if required.

  19. Determination of Diethyl Phthalate and Polyhexamethylene Guanidine in Surrogate Alcohol from Russia

    Directory of Open Access Journals (Sweden)

    Yulia B. Monakhova

    2011-01-01

    Full Text Available Analytical methods based on spectroscopic techniques were developed and validated for the determination of diethyl phthalate (DEP and polyhexamethylene guanidine (PHMG, which may occur in unrecorded alcohol. Analysis for PHMG was based on UV-VIS spectrophotometry after derivatization with Eosin Y and 1H NMR spectroscopy of the DMSO extract. Analysis of DEP was performed with direct UV-VIS and 1H NMR methods. Multivariate curve resolution and spectra computation methods were used to confirm the presence of PHMG and DEP in the investigated beverages. Of 22 analysed alcohol samples, two contained DEP or PHMG. 1H NMR analysis also revealed the presence of signals of hawthorn extract in three medicinal alcohols used as surrogate alcohol. The simple and cheap UV-VIS methods can be used for rapid screening of surrogate alcohol samples for impurities, while 1H NMR is recommended for specific confirmatory analysis if required.

  20. Spectroscopic determination of lysozyme conformational changes in the presence of trehalose and guanidine.

    Science.gov (United States)

    Barreca, Davide; Laganà, Giuseppina; Ficarra, Silvana; Gattuso, Giuseppe; Magazù, Salvatore; La Torre, Roberto; Tellone, Ester; Bellocco, Ersilia

    2013-06-01

    The bioprotective action of the disaccharide trehalose has been studied against the well-known denaturating agent, guanidine hydrochloride. The results indicated a direct influence of trehalose on both enzymatic activity and conformational changes of lysozyme, as shown by the decrease of the inactivation rate constant of about 1.48-fold and the loss of α-helix structure of lysozyme. In addition, ESI-MS hydrogen-deuterium (H/D) exchange experiments allowed us to correlate the structural and dynamic features of the protein in the presence of the two additives, highlighting as trehalose remarkably influenced this exchange by decreasing local protein environment changes and solvent accessibility to the amide peptide backbone, as further evidenced by circular dichroism and (1)H NMR measurements.

  1. Theoretical characterization and design of highly efficient iridium (III) complexes bearing guanidinate ancillary ligand.

    Science.gov (United States)

    Ren, Xin-Yao; Wu, Yong; Wang, Li; Zhao, Liang; Zhang, Min; Geng, Yun; Su, Zhong-Min

    2014-06-01

    A density functional theory/time-depended density functional theory was used to investigate the synthesized guanidinate-based iridium(III) complex [(ppy)2Ir{(N(i)Pr)2C(NPh2)}] (1) and two designed derivatives (2 and 3) to determine the influences of different cyclometalated ligands on photophysical properties. Except the conventional discussions on geometric relaxations, absorption and emission properties, many relevant parameters, including spin-orbital coupling (SOC) matrix elements, zero-field-splitting parameters, radiative rate constants (kr) and so on were quantitatively evaluated. The results reveal that the replacement of the pyridine ring in the 2-phenylpyridine ligand with different diazole rings cannot only enlarge the frontier molecular orbital energy gaps, resulting in a blue-shift of the absorption spectra for 2 and 3, but also enhance the absorption intensity of 3 in the lower-energy region. Furthermore, it is intriguing to note that the photoluminescence quantum efficiency (ΦPL) of 3 is significantly higher than that of 1. This can be explained by its large SOC value(n=3-4) and large transition electric dipole moment (μS3), which could significantly contribute to a larger kr. Besides, compared with 1, the higher emitting energy (ET1) and smaller (2) value for 3 may lead to a smaller non-radiative decay rate. Additionally, the detailed results also indicate that compared to 1 with pyridine ring, 3 with imidazole ring performs a better hole injection ability. Therefore, the designed complex 3 can be expected as a promising candidate for highly efficient guanidinate-based phosphorescence emitter for OLEDs applications. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Implications of the use of the labelled benzyl guanidine derivatives in nuclear medicine

    International Nuclear Information System (INIS)

    Zhagar, I.

    1994-01-01

    The development and synthesis of various labelled benzyl guanidine derivatives is described. After a brief outline of the tracer characteristics and the whole body imaging with 131- I -MIBG, 'pitfalls' of the visualization of sympathochromafine tissues and the possibilities of various pharmacological impacts on scintigraphy are discussed. Special emphasis is given to dosimetric and methodological aspects of MIBG scintigraphy in children, as well as to some new diagnostic applications of labelled benzyl guanidine in cardiology and pulmology. Whole body scintigraphy with 131-I-MIBG performed in groups of patients with pheochromocytoma, paraganglioma, neuroblastoma, medullary thyroid carcinoma, carcinoid and malignant insulinoma. Tumor, myocardial and salivary gland uptake of MIBG were estimated semi quantitatively, according to the method of Nakajo. The uptake of 131-I-MIBG was calculated from the activity measured prior and after the application and images acquired and was expressed as percent of dose administered.The results obtained confirm the high sensitivity and specificity of 131- I - MIBG in the scintigraphic evaluation of pheochromocytoma and euroblastoma. In medullary thyroid carcinoma it was found less sensitive than 99m Tc(V) -DMS A scan. The clinical evolution and uptake values were very well correlated. In patients developing bone marrow infiltration, uptake in primary tumor diminished. Good response to operative therapy in pheochromocytoma patients as well as to chemotherapy with neuroblastoma, was associated with an increase of myocardial MIBG uptake. There was highly significant negative correlation between myocardial uptake of MIBG and urinary catecholamine concentrations. Results obtained in determination 131- I -MIBG uptake in some neural crest tumors lead to the conclusion that the choice of background regions of interest can significantly influence the final results of quantification. (author)

  3. Synthesis of hydroxylamine-15 N.HCl

    International Nuclear Information System (INIS)

    Baldea, Aurel

    2001-01-01

    15 N labelled hydroxylamine is one of the starting substance for synthesis of labelled oximes. Industrial procedure was chosen to prepare hydroxylamine- 15 N. Sodium nitrite reduced by sodium bisulfite and sulfur dioxide, at temperature of 0-2 deg. C, produces sodium hydroxylamine disulfonate. The reaction mixture is treated with acetone and the resulting acetoxime is distilled. In order to obtain crystalline hydroxylamine hydrochloride, hydrochloric acid is added to the distillate and the solution is evaporated to dryness. The crude product was purified by recristallization, yielding 62-65% of theoretical amount. Labelled ammonium chloride formed as byproduct can be recovered improving 15 N balance. IR spectra is used for chemical analysis and mass spectrometry for isotopic analysis. For this purpose hydroxylamine- 15 N is converted into molecular nitrogen. (author)

  4. Non-LTE calculation of HCL earthlimb emission and implication for detection of HCl in the atmosphere

    Science.gov (United States)

    Kumer, J. B.; James, T. C.

    1982-01-01

    Calculation results are presented for the contribution of the non-Local Thermodynamic Equilibrium process of resonant scattering of sunlight in the 1-0 band of HCl to the earthlimb radiance, for the case of tangent altitudes from 20 to 90 km. It is established that the mechanism in question is a significant contributor to radiance at altitudes as low as 20 km, and that it becomes greater than the Local Thermodynamic Equilibrium contribution above 40 km. Attention is given to the prospects for detection of HCl at altitudes approaching 80 km, by means of the Cryogenic Limb Array Etalon Spectrometer scheduled for deployment by the NASA Upper Atmospheric Research Satellite.

  5. Sidewall Covalent Functionalization of Single Wall Carbon Nanotubes through C-N Bond Forming Reactions of Fluoronanotubes with Urea, Guanidine and Thiourea (Preprint)

    National Research Council Canada - National Science Library

    Pulikkathara, Merlyn X; Khabashesku, Valery N

    2007-01-01

    ...) as starting materials in the reactions with either urea, thiourea, or guanidine. Through these reactions, the derivatives with terminal amide and heteroamide groups on the nanotube sidewalls have been prepared...

  6. Formulation and Evaluation of Tramadol HCl Matrix Tablets Using ...

    African Journals Online (AJOL)

    Formulation and Evaluation of Tramadol HCl Matrix Tablets Using Carbopol ... to 83 % compared with the release rate of 99 % for the formulation with D:P ratio of 10:3. Kinetic analysis indicates that drug release mechanism was anomalous ...

  7. Water formation via HCl oxidation on Cu(1 0 0)

    Energy Technology Data Exchange (ETDEWEB)

    Suleiman, Ibrahim A., E-mail: isuleman@taibahu.edu.sa [College of Engineering, Taibah University, Yanbu 41911 (Saudi Arabia); Radny, Marian W. [School of Mathematical and Physical Sciences, The University of Newcastle, Callaghan, NSW 2308 (Australia); Institute of Physics, Poznan University of Technology, 62-956 Poznan (Poland); Gladys, Michael J.; Smith, Phillip V. [School of Mathematical and Physical Sciences, The University of Newcastle, Callaghan, NSW 2308 (Australia); Mackie, John C. [School of Engineering, The University of Newcastle, Callaghan, NSW 2308 (Australia); School of Chemistry, The University of Sydney (Australia); Stockenhuber, Michael; Kennedy, Eric M. [School of Engineering, The University of Newcastle, Callaghan, NSW 2308 (Australia); Dlugogorski, Bogdan Z. [School of Engineering, The University of Newcastle, Callaghan, NSW 2308 (Australia); School of Engineering and Information Technology, Murdoch University, Perth (Australia)

    2014-04-01

    Graphical abstract: This work investigates water formation on the Cu(1 0 0) surface via HCl oxidation using density functional theory and periodic slabs. We show that there are two different pathways for water formation on the surface depending on the temperature and oxygen coverage. - Highlights: • Pre-adsorbed chlorine increases the stability of water on Cu(1 0 0). • Two different pathways describe water formation on Cu(1 0 0) via HCl oxidation. • The mechanism of H{sub 2}O formation depends on the temperature and oxygen coverage. - Abstract: Using density functional theory and periodic slabs, we have studied water formation via HCl oxidation on the Cu(1 0 0) surface. We show that while adsorbed chlorine increases the stability of water on the Cu(1 0 0) surface, water molecules dissociate immediately when located next to an oxygen atom. We also show that these competing interactions, when arising from HCl reacting with oxygen on Cu(1 0 0), lead to water formation according to two different pathways depending on the temperature and oxygen coverage.

  8. The kinetics of titanium leaching of ilmenite using HCl

    International Nuclear Information System (INIS)

    MV Purwani; Herry Poernomo

    2015-01-01

    The research of ilmenite leaching of tailings processing zircon sand has been done. Tailings of processing zircon sand contain Zr, Ti, Nb and Fe. Determination of leaching kinetics of Ti on ilmenite using HCl was done on this research. Determination of reaction rate consist the influence of weight ratio of HCl to ilmenite, HCl molarity and temperature reaction. The experiment of kinetics was done by varying the temperature reaction from 70°C to 108°C and time parameter range 0 to 200 minutes. From data of research can be concluded that the greater of weight ratio of HCl with ilmenite, M HCl and reaction temperature, the faster rate of reaction. On weight ratio of HCl with ilmenite varied 4 - 20, average reaction rate along 50 minutes and instantaneous reaction rate in the first 50 minutes ranged from 0.0021 to 0.0032 gmol/(l.minute). Average reaction rate along 250 minutes ranged from 0.0005 to 0.0007 gmol/(l.minute) and instantaneous reaction rate at 50 minutes latest ranged from 0.0000 to 0.0001 gmol/(l.minute). For M HCl = 8 to 12.23 M, average reaction rate and instantaneous reaction rate in the first 50 minutes ranged from 0.0012 to 0.0026 gmol/(l.minute). Average reaction rate along 250 minutes ranged from 0.0004 to 0.0006 gmol/(l.minute) and instantaneous reaction rate at 50 minutes latest ranged from 0.0000 to 0.0001 gmol/(l.minute). On reaction temperature = 70 - 108°C, average reaction rate along 50 minutes and instantaneous reaction rate in the first 50 minutes ranged from 0.0012 to 0.0032 gmol/(l.minute). Average reaction rate along 250 minutes ranged from 0.0002 to 0.0006 gmol/(l.minute) and instantaneous reaction rate at 50 minutes latest ranged from 0.0000 to 0.0001 gmol/(l.minute). The leaching reaction of Ti in ilmenite was second order reaction. The relationship between temperature (T) with the reaction rate constant (k) are - ln k = 3333.2/T - 1.3685 or k = 1.3685. e-3333,2/T , frequency factor A = 1446 and activation energy E = 27.712 k

  9. Pharmacokinetic and bioequivalence study of itopride HCl in healthy volunteers.

    Science.gov (United States)

    Cho, Kyung-Jin; Cho, Wonkyung; Cha, Kwang-Ho; Park, Junsung; Kim, Min-Soo; Kim, Jeong-Soo; Hwang, Sung-Joo

    2010-01-01

    In the present study two different formulations containing 50 mg itopride HCl (N-[4-12-(dimethylamino)ethoxylbenzyl]-3,4-dimethoxybenzamide HCl, CAS 122898-67-3) were compared in 28 healthy male volunteers in order to compare the bioavailability and prove the bioequivalence. The study was performed in an open, single dose randomized, 2-sequence, crossover design in 28 healthy male volunteers with a one-week washout period. Blood samples for pharmacokinetic profiling were drawn at selected times during 24 h. The serum concentrations of itopride HCl were determined using a specific and sensitive HPLC method with fluorescence detection. The detection limit of itopride HCl was 5 ng/ml and no endogenous compounds were found to interfere with analysis. The mean AUC(0-4h), AUC(0 --> infinity), C(max), T(max) and T1/2 were 865.28 ng x h/ml, 873.04 ng x h/ml, 303.72 ng/ml, 0.75 h, and 2.95 h, respectively, for the test formulations, and 833.00 ng x h/ml, 830.97 ng x h/ml, 268.01 ng/ml, 0.78 h, and 2.83 h, respectively, for the reference formulation. Both primary target parameters AUC(0 --> infinity) and C(max) were log-transformed and tested parametrically by analysis of variance (ANOVA). 90% confidence intervals of AUC(0 --> infinity) and C(max) were 100.57%-109.56% and 105.46%-121.18%, respectively, and were in the range of acceptable limits of bioequivalence (80-125%). Based on these results, the two formulations of itopride HCl are considered to be bioequivalent.

  10. 78 FR 22911 - HCL America, Inc., a Subsidiary of HCL Technologies Limited, Including On-Site Leased Workers...

    Science.gov (United States)

    2013-04-17

    ... America Inc., a subsidiary of HCL Technologies Limited, Webster, New York (subject firm). Workers are... infrastructure services (hardware/software testing) for clients. The Department's Notice of determination was... subject firm whose unemployment insurance (UI) wages are reported through Segula Technologies The intent...

  11. CORROSION INHIBITION OF ALUMINUM ALLOY 3SR IN HCl BY POLYVINYLPYRROLIDONE AND POLYACRYLAMIDE: EFFECT OF MOLECULAR STRUCTURE ON INHIBITION EFFICIENCY

    OpenAIRE

    S. A. UMOREN

    2009-01-01

    The inhibitive performance of two water soluble polymers–polyacrylamide (PA) and polyvinylpyrrolidone (PVP) on the corrosion behavior of aluminum alloy 3SR in HCl solution was investigated using weight loss, hydrogen evolution, and thermometric methods at 30–60°C. Results obtained indicate that both polymers inhibited acid-induced corrosion of aluminum at the temperatures studied. PVP was found to be a better corrosion inhibitor than PA. All measurements from the three techniques show that in...

  12. The technique for calculation of equilibrium in heterogeneous systems of the InP-GaP-HCl type

    International Nuclear Information System (INIS)

    Voronin, V.A.; Prokhorov, V.A.; Goliusov, V.A.; Chuchmarev, S.K.

    1983-01-01

    Technique for calculation of equilibrium in heterogeneous systems based on A 1 3 B 5 -A 2 3 B 5 solid solutions implying the use of structural-topological models of chemical equilibrium in the investigated systems, is developed. Chemical equilibrium in the InP-GaP-HCl systems is analyzed by means of the suggested technique and the equilibrium composition of the gas phase is calculated

  13. The effect of polyhexamethylene guanidine hydrochloride (PHMG) derivatives introduced into polylactide (PLA) on the activity of bacterial enzymes

    OpenAIRE

    Walczak, Maciej; Richert, Agnieszka; Burkowska-But, Aleksandra

    2014-01-01

    The present study was aimed at investigating bactericidal properties of polylactide (PLA) films containing three different polyhexamethylene guanidine hydrochloride (PHMG) derivatives and effect of the derivatives on extracellular hydrolytic enzymes and intracellular dehydrogenases. All PHMG derivatives had a slightly stronger bactericidal effect on Staphylococcus aureus than on E. coli but only PHMG granular polyethylene wax (at the concentration of at least 0.6 %) has a bactericidal effect....

  14. The inhibition effect of Azure A on mild steel in 1 M HCl. A complete study: Adsorption, temperature, duration and quantum chemical aspects

    International Nuclear Information System (INIS)

    Özkır, Demet; Kayakırılmaz, Kadriye; Bayol, Emel; Gürten, A. Ali; Kandemirli, Fatma

    2012-01-01

    Highlights: ► Azure A molecule is found to be a good inhibitor for mild steel in HCl solution. ► SEM results clearly indicate that a protective film formation occurred on the mild steel surface. ► The long term corrosion tests are cleared that the Azure A has effectively protected the mild steel in HCl solution. ► The quantum chemical measurements were cleared the reactive sites and charges of atoms in the molecule. - Abstract: In this study, inhibition effect of Azure A on mild steel in 1.0 M HCl were evaluated by using electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR), and potentiodynamic polarization and scanning electron microscope (SEM) methods. These studies were carried out at different concentrations, temperatures and durations. The inhibitor molecules were chemisorbed on electrode surface according to the Langmuir adsorption isotherm. The quantum chemical calculations were employed to give further insight into the inhibition mechanism of Azure A.

  15. Ir Spectroscopic Studies on Microsolvation of HCl by Water

    Science.gov (United States)

    Mani, Devendra; Schwan, Raffael; Fischer, Theo; Dey, Arghya; Kaufmann, Matin; Redlich, Britta; van der Meer, Lex; Schwaab, Gerhard; Havenith, Martina

    2016-06-01

    Acid dissociation reactions are at the heart of chemistry. These reactions are well understood at the macroscopic level. However, a microscopic level understanding is still in the early stages of development. Questions such as 'how many H_2O molecules are needed to dissociate one HCl molecule?' have been posed and explored both theoretically and experimentally.1-5 Most of the theoretical calculations predict that four H_2O molecules are sufficient to dissociate one HCl molecule, resulting in the formation of a solvent separated H_3O+(H_2O)3Cl- cluster.1-3 IR spectroscopy in helium nanodroplets has earlier been used to study this dissociation process.3-5 However, these studies were carried out in the region of O-H and H-Cl stretch, which is dominated by the spectral features of undissociated (HCl)m-(H_2O)n clusters. This contributed to the ambiguity in assigning the spectral features arising from the dissociated cluster.4,5 Recent predictions from Bowman's group, suggest the presence of a broad spectral feature (1300-1360 wn) for the H_3O+(H_2O)3Cl- cluster, corresponding to the umbrella motion of H_3O+ moiety.6 This region is expected to be free from the spectral features due to the undissociated clusters. In conjunction with the FELIX laboratory, we have performed experiments on the (HCl)m(H_2O)n (m=1-2, n≥4) clusters, aggregated in helium nanodroplets, in the 900-1700 wn region. Mass selective measurements on these clusters revealed the presence of a weak-broad feature which spans between 1000-1450 wn and depends on both HCl as well as H_2O concentration. Measurements are in progress for the different deuterated species. The details will be presented in the talk. References: 1) C.T. Lee et al., J. Chem. Phys., 104, 7081 (1996). 2) H. Forbert et al., J. Am. Chem. Soc., 133, 4062 (2011). 3) A. Gutberlet et al., Science, 324, 1545 (2009). 4) S. D. Flynn et al., J. Phys. Chem. Lett., 1, 2233 (2010). 5) M. Letzner et al., J. Chem. Phys., 139, 154304 (2013). 6) J. M

  16. Radiation chemical behavior of Rh(III) in HClO4 and HNO3

    International Nuclear Information System (INIS)

    Vladimirova, M.V.; Khalkina, E.V.

    1995-01-01

    The radiation chemical behavior of Rh is very interesting since Rh accumulates in irradiated U but has not been reported in the literature. Scattered data do exist for the radiation chemical behavior of Rh(III) in weakly acidic and alkaline solutions. Pulsed radiolysis was used to investigate the formation of unstable oxidation states of Rh during reduction and oxidation of Rh(III) in neutral solutions. The rate constant of the reaction Rh(III) + e aq - was found to be 6·10 10 liter/mole·sec. The radiation chemical behavior of Rh(III) toward γ-radiolysis in neutral, weakly acidic (up to 0.1 N), and alkaline solutions was examined. In neutral solutions of [Rh(NH 3 ) 5 Cl]Cl 2 and RhCl 3 , metallic Rh is formed. The degree of reduction is ∼ 1%. In neutral and weakly acidic solutions of Rh(NO 3 ) 3 , Rh 2 O 3 ·xH 2 O is formed. Irradiation of Rh(ClO 4 ) 3 solutions produces no reduction. The radiation chemical behavior of Rh(III) in HClO 4 and HNO 3 solutions at concentrations > 1 M is studied in the present work

  17. INHIBITION OF CORROSION OF ZINC IN (HNO3 + HCl) ACID ...

    African Journals Online (AJOL)

    2015-05-01

    May 1, 2015 ... corrosion inhibitor for zinc in phosphoric acid. Vashi et al.[8-9] studied the corrosion inhibition of zinc in (HNO3 + H2SO4) and (HNO3 + H3PO4) binary acid mixture by aniline. In the present work, the role of aniline as inhibitor for corrosion of zinc in (HNO3 + HCl) binary acid mixture has been reported. 2.

  18. Guanidine-based polymer brushes grafted onto silica nanoparticles as efficient artificial phosphodiesterases.

    Science.gov (United States)

    Savelli, Claudia; Salvio, Riccardo

    2015-04-07

    Polymer brushes grafted to the surface of silica nanoparticles were fabricated by atom-transfer radical polymerization (ATRP) and investigated as catalysts in the cleavage of phosphodiesters. The surfaces of silica nanoparticles were functionalized with an ATRP initiator. Surface-initiated ATRP reactions, in varying proportions, of a methacrylate moiety functionalized with a phenylguanidine moiety and an inert hydrophilic methacrylate species afforded hybrid nanoparticles that were characterized with potentiometric titrations, thermogravimetric analysis, and SEM. The activity of the hybrid nanoparticles was tested in the transesterification of the RNA model compound 2-hydroxypropyl para-nitrophenylphosphate (HPNP) and diribonucleoside monophosphates. A high catalytic efficiency and a remarkable effective molarity, thus overcoming the effective molarities previously observed for comparable systems, indicate the existence of an effective cooperation of the guanidine/guanidinium units and a high level of preorganization in the nanostructure. The investigated system also exhibits a marked and unprecedented selectivity for the diribonucleoside sequence CpA. The results presented open up the way for a novel and straightforward strategy for the preparation of supramolecular catalysts. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Sampling polyhexamethylene guanidine aerosols using eosin Y-coated glass beads

    International Nuclear Information System (INIS)

    Choi, Sang Hyun; Park, Seon Kyung; Kang, Hyun Joong; Kwon, Jung Hwan; Lee, Kyu Hong

    2015-01-01

    Fatalities caused by the use of polyhexamethylene guanidine (PHMG), a general-purpose chemical germicide used as a humidifier disinfectant in Korea, have raised concerns about exposure to biocide aerosols in indoor environments. A sampler capable of accumulating PHMG from aqueous aerosols was developed as an alternative to low-volume air samplers. This sampler was prepared by placing glass beads coated with 2-(2,4,5,7-tetrabromo-6-oxido-3-oxo-3H-xanthen-9-yl)benzoate (Eosin Y) in a custom-made plastic holder. Passive sampling rates, measured in a bench-top exposure chamber at two different aqueous PHMG aerosol generation rates, were found to be independent of the experimental conditions. This suggests that the capacity of the sampler to accumulate the PHMG aerosol was sufficient for the sampling duration tested. However, the passive sampling rate was 7.6 × 10"−"6 m"3/h for the sampler area of 22 cm"2. This rate is lower than the typical human breathing rate and inadequate for quantitative instrumental analyses at low concentrations in indoor air. A 30-fold enhancement of the sampling rate was achieved by forced convection using a commercial battery-operated fan at ≥2000 rpm. With this accelerated sampling rate, the sampler could be used to monitor time-integrated concentrations of PHMG aerosols in the air

  20. Low-dose cadmium exposure exacerbates polyhexamethylene guanidine-induced lung fibrosis in mice.

    Science.gov (United States)

    Kim, Min-Seok; Kim, Sung-Hwan; Jeon, Doin; Kim, Hyeon-Young; Han, Jin-Young; Kim, Bumseok; Lee, Kyuhong

    2018-01-01

    Cadmium (Cd) is a toxic metal present in tobacco smoke, air, food, and water. Inhalation is an important route of Cd exposure, and lungs are one of the main target organs for metal-induced toxicity. Cd inhalation is associated with an increased risk of pulmonary diseases. The present study aimed to assess the effects of repeated exposure to low-dose Cd in a mouse model of polyhexamethylene guanidine (PHMG)-induced lung fibrosis. Mice were grouped into the following groups: vehicle control (VC), PHMG, cadmium chloride (CdCl 2 ), and PHMG + CdCl 2 . Animals in the PHMG group exhibited increased numbers of total cells and inflammatory cells in the bronchoalveolar lavage fluid (BALF) accompanied by inflammation and fibrosis in lung tissues. These parameters were exacerbated in mice in the PHMG + CdCl 2 group. In contrast, mice in the CdCl 2 group alone displayed only minimal inflammation in pulmonary tissue. Expression of inflammatory cytokines and fibrogenic mediators was significantly elevated in lungs of mice in the PHMG group compared with that VC. Further, expression of these cytokines and mediators was enhanced in pulmonary tissue in mice administered PHMG + CdCl 2 . Data demonstrate that repeated exposure to low-dose Cd may enhance the development of PHMG-induced pulmonary fibrosis.

  1. Oleanolic acid acetate attenuates polyhexamethylene guanidine phosphate-induced pulmonary inflammation and fibrosis in mice.

    Science.gov (United States)

    Kim, Min-Seok; Han, Jin-Young; Kim, Sung-Hwan; Jeon, Doin; Kim, Hyeon-Young; Lee, Seung Woong; Rho, Mun-Chual; Lee, Kyuhong

    2018-06-01

    Oleanolic acid acetate (OAA), triterpenoid compound isolated from Vigna angularis (azuki bean), has been revealed anti-inflammatory in several studies. We investigated the effects of OAA against polyhexamethylene guanidine phosphate (PHMG-P)-induced pulmonary inflammation and fibrosis in mice. OAA treatment effectively alleviated PHMG-P-induced lung injury, including the number of total and differential cell in BAL fluid, histopathological lesions and hydroxyproline content in a dose dependent manner. Moreover, OAA treatment significantly decreased the elevations of IL-1β, IL-6, TNF-α, TGF-β1, and fibronectin, and the activation of the NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome in the lungs of PHMG-P-treated mice. Cytokines are known to be key modulators in the inflammatory responses that drive progression of fibrosis in injured tissues. The activation of NLRP3 inflammasome has been reported to be involved in induction of inflammatory cytokines. These results indicate that OAA may mitigate the inflammatory response and development of pulmonary fibrosis in the lungs of mice treated with PHMG-P. Copyright © 2018. Published by Elsevier B.V.

  2. Damage of Escherichia coli membrane by bactericidal agent polyhexamethylene guanidine hydrochloride: micrographic evidences.

    Science.gov (United States)

    Zhou, Z X; Wei, D F; Guan, Y; Zheng, A N; Zhong, J J

    2010-03-01

    The purpose of this study was to provide micrographic evidences for the damaged membrane structure and intracellular structure change of Escherichia coli strain 8099, induced by polyhexamethylene guanidine hydrochloride (PHMG). The bactericidal effect of PHMG on E. coli was investigated based on beta-galactosidase activity assay, fluorescein-5-isothiocyanate confocal laser scanning microscopy, field emission scanning electron microscopy and transmission electron microscopy. The results revealed that a low dose (13 microg ml(-1)) of PHMG slightly damaged the outer membrane structure of the treated bacteria and increased the permeability of the cytoplasmic membrane, while no significant damage was observed to the morphological structure of the cells. A high dose (23 microg ml(-1)) of PHMG collapsed the outer membrane structure, led to the formation of a local membrane pore across the membrane and badly damaged the internal structure of the cells. Subsequently, intracellular components were leaked followed by cell inactivation. Dose-dependent membrane disruption was the main bactericidal mechanism of PHMG. The formation of the local membrane pores was probable after exposure to a high dose (23 microg ml(-1)) of PHMG. Micrographic evidences were provided about the damaged membrane structure and intracellular structure change of E. coli. The presented information helps understand the bactericidal mechanism of PHMG by membrane damage.

  3. Polyhexamethylene guanidine hydrochloride shows bactericidal advantages over chlorhexidine digluconate against ESKAPE bacteria.

    Science.gov (United States)

    Zhou, Zhongxin; Wei, Dafu; Lu, Yanhua

    2015-01-01

    More information regarding the bactericidal properties of polyhexamethylene guanidine hydrochloride (PHMG) against clinically important antibiotic-resistant ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens needs to be provided for its uses in infection control. The bactericidal properties of PHMG and chlorhexidine digluconate (CHG) were compared based on their minimum inhibitory concentrations (MICs), minimum bactericidal concentrations, and time-course-killing curves against clinically important antibiotic-susceptible and antibiotic-resistant ESKAPE pathogens. Results showed that PHMG exhibited significantly higher bactericidal activities against methicillin-resistant Staphylococcus aureus, carbapenem-resistant Klebsiella pneumoniae, and ceftazidime-resistant Enterobacter spp. than CHG. A slight bactericidal advantage over CHG was obtained against vancomycin-resistant Enterococcus faecium, ciprofloxacin- and levofloxacin-resistant Acinetobacter spp., and multidrug-resistant Pseudomonas aeruginosa. In previous reports, PHMG had higher antimicrobial activity against almost all tested Gram-negative bacteria and several Gram-positive bacteria than CHG using MIC test. These studies support the further development of covalently bound PHMG in sterile-surface materials and the incorporation of PHMG in novel disinfectant formulas. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

  4. Reactivity of Zinc Halide Complexes Containing Camphor-Derived Guanidine Ligands with Technical rac-Lactide

    Directory of Open Access Journals (Sweden)

    Angela Metz

    2017-11-01

    Full Text Available Three new zinc complexes with monoamine–guanidine hybridligands have been prepared, characterized by X-ray crystallography and NMR spectroscopy, and tested in the solvent-free ring-opening polymerization of rac-lactide. Initially the ligands were synthesized from camphoric acid to obtain TMGca and DMEGca and then reacted with zinc(II halides to form zinc complexes. All complexes have a distorted tetrahedral coordination. They were utilized as catalysts in the solvent-free polymerization of technical rac-lactide at 150 °C. Colorless polylactide (PLA can be produced and after 2 h conversion up to 60% was reached. Furthermore, one zinc chlorido complex was tested with different qualities of lactide (technical and recrystallized and with/without the addition of benzyl alcohol as a co-initiator. The kinetics were monitored by in situ FT-IR or 1H NMR spectroscopy. All kinetic measurements show first-order behavior with respect to lactide. The influence of the chiral complexes on the stereocontrol of PLA was examined. Moreover, with MALDI-ToF measurements the end-group of the obtained polymer was determined. DFT and NBO calculations give further insight into the coordination properties. All in all, these systems are robust against impurities and water in the lactide monomer and show great catalytic activity in the ROP of lactide.

  5. Synthesis and characterization of azo-guanidine based alcoholic media naked eye DNA sensor

    Science.gov (United States)

    Hashmat, Uzma; Yousaf, Muhammad; Lal, Bhajan; Ullah, Shafiq; Holder, Alvin A.; Badshah, Amin

    2016-01-01

    DNA sensing always has an open meadow of curiosity for biotechnologists and other researchers. Recently, in this field, we have introduced an emerging class of molecules containing azo and guanidine functionalities. In this study, we have synthesized three new compounds (UA1, UA6 and UA7) for potential application in DNA sensing in alcoholic medium. The synthesized materials were characterized by elemental analysis, FTIR, UV-visible, 1H NMR and 13C NMR spectroscopies. Their DNA sensing potential were investigated by UV-visible spectroscopy. The insight of interaction with DNA was further investigated by electrochemical (cyclic voltammetry) and hydrodynamic (viscosity) studies. The results showed that compounds have moderate DNA binding properties, with the binding constants range being 7.2 × 103, 2.4 × 103 and 0.2 × 103 M−1, for UA1, UA6 and UA7, respectively. Upon binding with DNA, there was a change in colour (a blue shift in the λmax value) which was observable with a naked eye. These results indicated the potential of synthesized compounds as DNA sensors with detection limit 1.8, 5.8 and 4.0 ng µl−1 for UA1, UA6 and UA7, respectively. PMID:28018613

  6. Highly Active N,O Zinc Guanidine Catalysts for the Ring-Opening Polymerization of Lactide.

    Science.gov (United States)

    Schäfer, Pascal M; Fuchs, Martin; Ohligschläger, Andreas; Rittinghaus, Ruth; McKeown, Paul; Akin, Enver; Schmidt, Maximilian; Hoffmann, Alexander; Liauw, Marcel A; Jones, Matthew D; Herres-Pawlis, Sonja

    2017-09-22

    New zinc guanidine complexes with N,O donor functionalities were prepared, characterized by X-Ray crystallography, and examined for their catalytic activity in the solvent-free ring-opening polymerization (ROP) of technical-grade rac-lactide at 150 °C. All complexes showed a high activity. The fastest complex [ZnCl 2 (DMEGasme)] (C1) produced colorless poly(lactide) (PLA) after 90 min with a conversion of 52 % and high molar masses (M w =69 100, polydispersity=1.4). The complexes were tested with different monomer-to-initiator ratios to determine the rate constant k p . Furthermore, a polymerization with the most active complex C1 was monitored by in situ Raman spectroscopy. Overall, conversion of up to 90 % can be obtained. End-group analysis was performed to clarify the mechanism. All four complexes combine robustness against impurities in the lactide with high polymerization rates, and they represent the fastest robust lactide ROP catalysts to date, opening new avenues to a sustainable ROP catalyst family for industrial use. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Sampling polyhexamethylene guanidine aerosols using eosin Y-coated glass beads

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Sang Hyun; Park, Seon Kyung; Kang, Hyun Joong; Kwon, Jung Hwan [Korea University, Seoul (Korea, Republic of); Lee, Kyu Hong [Korea Institute of Toxicology, Jeongeup (Korea, Republic of)

    2015-07-15

    Fatalities caused by the use of polyhexamethylene guanidine (PHMG), a general-purpose chemical germicide used as a humidifier disinfectant in Korea, have raised concerns about exposure to biocide aerosols in indoor environments. A sampler capable of accumulating PHMG from aqueous aerosols was developed as an alternative to low-volume air samplers. This sampler was prepared by placing glass beads coated with 2-(2,4,5,7-tetrabromo-6-oxido-3-oxo-3H-xanthen-9-yl)benzoate (Eosin Y) in a custom-made plastic holder. Passive sampling rates, measured in a bench-top exposure chamber at two different aqueous PHMG aerosol generation rates, were found to be independent of the experimental conditions. This suggests that the capacity of the sampler to accumulate the PHMG aerosol was sufficient for the sampling duration tested. However, the passive sampling rate was 7.6 × 10{sup −6} m{sup 3}/h for the sampler area of 22 cm{sup 2}. This rate is lower than the typical human breathing rate and inadequate for quantitative instrumental analyses at low concentrations in indoor air. A 30-fold enhancement of the sampling rate was achieved by forced convection using a commercial battery-operated fan at ≥2000 rpm. With this accelerated sampling rate, the sampler could be used to monitor time-integrated concentrations of PHMG aerosols in the air.

  8. Effects on Energy Metabolism of Two Guanidine Molecules, (Boc)2 -Creatine and Metformin.

    Science.gov (United States)

    Garbati, Patrizia; Ravera, Silvia; Scarfì, Sonia; Salis, Annalisa; Rosano, Camillo; Poggi, Alessandro; Damonte, Gianluca; Millo, Enrico; Balestrino, Maurizio

    2017-09-01

    Several enzymes are involved in the energy production, becoming a possible target for new anti-cancer drugs. In this paper, we used biochemical and in silico studies to evaluate the effects of two guanidine molecules, (Boc) 2 -creatine and metformin, on creatine kinase, an enzyme involved in the regulation of intracellular energy levels. Our results show that both drugs inhibit creatine kinase activity; however, (Boc) 2 -creatine displays a competitive inhibition, while metformin acts with a non-competitive mechanism. Moreover, (Boc) 2 -creatine is able to inhibit the activity of hexokinase with a non-competitive mechanism. Considering that creatine kinase and hexokinase are involved in energy metabolism, we evaluated the effects of (Boc) 2 -creatine and metformin on the ATP/AMP ratio and on cellular proliferation in healthy fibroblasts, human breast cancer cells (MDA-MB-468), a human neuroblastoma cell line (SH-SY5Y), a human Hodgkin lymphoma cell line (KMH2). We found that healthy fibroblasts were only partially affected by (Boc) 2 -creatine, while both ATP/AMP ratio and viability of the three cancer cell lines were significantly decreased. By inhibiting both creatine kinase and hexokinase, (Boc) 2 -creatine appears as a promising new agent in anticancer treatment. Further research is needed to understand what types of cancer cells are most suitable to treatment by this new compound. J. Cell. Biochem. 118: 2700-2711, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  9. Determination of Pu Oxidation states in the HCl Media Using with UV-Visible Absorption Spectroscopic Techniques

    International Nuclear Information System (INIS)

    Lee, Myung Ho; Suh, Mu Yeol; Park, Kyoung Kyun; Park, Yeong Jae; Kim, Won Ho

    2006-01-01

    The spectroscopic characteristics of Pu (III, IV, V, VI) in the HCl media were investigated by measuring Pu oxidation states using a UV-Vis-NIR spectrophotometer (400-1200 nm) after adjusting Pu oxidation states with oxidation/reduction reagents. Pu in stock solution was reduced to Pu(III) with NH 2 OH · HCl, and oxidized to Pu(IV) and Pu(VI) with NaNO 2 and HCIO 4 , respectively. Also, Pu(V) was adjusted in the Pu(VI) solution with NH 2 OH · HCl. The major absorption peaks of Pu (IV) and Pu(III) were measured in the 470 nm and 600 nm, respectively. The major absorption peaks of Pu (VI) and Pu(V) were measured in the 830 nm and 1135 nm, respectively. There was not found to be significant changes of UV-V is absorption spectra for Pu(III), Pu(IV) and Pu(VI) with aging time, except that an unstable Pu(V) immediately reduced to Pu(III).

  10. The Influence of Variation in Time and HCl Concentration to the Glucose Produced from Kepok Banana

    Science.gov (United States)

    Widodo M, Rohman; Noviyanto, Denny; RM, Faisal

    2016-01-01

    Kepok banana (Musa paradisiaca) is a plant that has many advantagesfrom its fruit, stems, leaves, flowers and cob. However, we just tend to take benefit from the fruit. We grow and harvest the fruit without taking advantages from other parts. So they would be a waste or detrimental to animal nest if not used. The idea to take the benefit from the banana crop yields, especially cob is rarely explored. This study is an introduction to the use of banana weevil especially from the glucose it contains. This study uses current methods of hydrolysis using HCl as a catalyst with the concentration variation of 0.4 N, 0.6 N and 0.8 N and hydrolysis times variation of 20 minutes, 25 minutes and 30 minutes. The stages in the hydrolysis include preparation of materials, the process of hydrolysis and analysis of test results using Fehling and titrate with standard glucose solution. HCl is used as a catalyst because it is cheaper than the enzyme that has the same function. NaOH 60% is used for neutralizing the pH of the filtrate result of hydrolysis. From the results of analysis, known thatthe biggest yield of glucose is at concentration 0.8 N and at 30 minutes reaction, it contains 6.25 gram glucose / 20 gram dry sampel, and the convertion is 27.22% at 20 gram dry sampel.

  11. Extraction of heavy metals from contaminated soils using EDTA and HCl

    Directory of Open Access Journals (Sweden)

    Hatem Asel Gzar

    2015-01-01

    Full Text Available The present study examines the extraction of lead (Pb, cadmium (Cd and nickel (Ni from a contaminated soil by washing process. Ethylenediaminetetraacetic acid disodium salt (Na2EDTA and hydrochloric acid (HCl solution were used as extractants. Soil washing is one of the most suitable in-situ/ ex-situ remediation method in removing heavy metals. Soil was artificially contaminated with 500 mg/kg (Pb , Cd and Ni . A set of batch experiments were carried out at different conditions of extractant concentration , contact time, pH and agitation speed. The results showed that the maximum removal efficiencies of (Cd, Pb and Ni were (97, 88 and 24 % respectively using ( 0.1 M Na2EDTA. While the maximum removal efficiencies using (1M HCl were (98, 94 and 55% respectively. The experimental data of batch extraction were applied in four kinetic models; first order, parabolic diffusion, two constant and Elovich model. The parabolic diffusion was the most fitted to the experimental data.

  12. Isomers of Poly Aminophenol: Chemical Synthesis, Characterization, and Its Corrosion Protection Aspect on Mild Steel in 1 M HCl

    OpenAIRE

    Thenmozhi, G.; Arockiasamy, P.; Santhi, R. Jaya

    2014-01-01

    The oxidative chemical polymerizations of three isomers of aminophenol, ortho, meta, and para (PoAP, PmAP, and PpAP), were performed in aqueous HCl using ammonium persulfate as an oxidant at 0–3°C. The synthesized polymers were characterized by employing elemental analysis, GPC, UV-VIS-NIR, FT-IR, XRD, and TGA. The corrosion inhibition effect of these three polymers on mild steel in 1 M HCl solution was studied by using electrochemical techniques such as potentiodynamic polarization and elect...

  13. Effects of HCl and HNO3 on the oxidation of toluene to benzaldehyde by H2O2 over TS-1 modified with Al in aqueous phase

    Directory of Open Access Journals (Sweden)

    Paricha Pongjirawat

    2014-09-01

    Full Text Available This research studies effects of HCl and HNO3 in aqueous solution on the oxidation reaction between toluene and hydrogen peroxide to benzaldehyde over titanium silicalite-1 catalyst modified with Al. The reaction was carried out at reaction temperature 120°C in a pressurized autoclave reactor. The research found that the addition of HCl and HNO3 not only increases the concentration of toluene in the aqueous phase but also increases the formation of benzaldehyde as main product in the reaction.

  14. Volumetric properties of ascorbic acid (vitamin C) and thiamine hydrochloride (vitamin B1) in dilute HCl and in aqueous NaCl solutions at (283.15, 293.15, 298.15, 303.15, 308.15, and 313.15) K

    International Nuclear Information System (INIS)

    Ayranci, Guler; Sahin, Melike; Ayranci, Erol

    2007-01-01

    Apparent molar volumes and apparent molar isentropic compressibilities of ascorbic acid (vitamin C) and thiamine hydrochloride (vitamin B 1 ) were determined from accurately measured density and sound velocity data in water and in aqueous NaCl solutions at (283.15, 293.15, 298.15, 303.15, 308.15, and 313.15) K. These volume and compressibility data were extrapolated to zero concentration using suitable empirical or theoretical equations to determine the corresponding infinite dilution values. Apparent molar expansibilities at infinite dilution were determined from slopes of apparent molar volume vs. temperature plots. Ionization of both ascorbic acid and thiamine hydrochloride were suppressed using sufficiently acidic solutions. Apparent molar volumes at infinite dilution for ascorbic acid and thiamine hydrochloride were found to increase with temperature in acidic solutions and in the presence of co-solute, NaCl. Apparent molar expansibility at infinite dilution were found to be constant over the temperature range studied and were all positive, indicating the hydrophilic character of the two vitamins studied in water and in the presence of co-solute, NaCl. Apparent molar isentropic compressibilities of ascorbic acid at infinite dilution were positive in water and in the presence of co-solute, NaCl, at low molalities. Those of thiamine hydrochloride at infinitive dilution were all negative, consistent with its ionic nature. Transfer apparent molar volumes of vitamins at infinite dilution from water solutions to NaCl solutions at various temperatures were determined. The results were interpreted in terms of complex vitamin-water-co-solute (NaCl) interactions

  15. EFEK IRIGASI TUNGGAL LARUTAN TETRASIKLIN HCl 10% SETELAH SKELING DAN PENGHALUSAN AKAR TERHADAP PERUBAHAN KLINIS PERIODONTITIS KRONIS POKET 4-6 MM

    Directory of Open Access Journals (Sweden)

    Natalina Natalina

    2015-07-01

    Full Text Available Chronic adult periodontitis (CAP is the most common type of periodontal disease. Treatment of moderate CAP has primarily been directed at the physical removal of bacterial plaque, calculus and contaminated cementum by scaling and root planing (SRP with or without surgical access. Irrigation solutions reach the apical portion of the pocket has flushing action properties and easy to apply. Tetracycline HCl (TTC HCl solutions demonstrated its antimicrobial activity against subgingival microflora, shown to be substantive to dentin surface and subsequently released in active form, also has anti-collagenase properties. This study evaluates the clinical outcomes of treatment with locally TTC HCl 10% irrigation as an adjunct to SRP in subset of moderate CAP patients. The data examined were obtained from 24 patients. All patient were scaled and root planed prior to baseline measurement. The patients were monitored by parameters ; bleeding on probing (BOP, probing pocket depth (PPD, and attachment loss (LA. 56 contralateral surface exhibiting residual pocket depths 4-6mm were randomly assigned as test or control sites. After baseline measurement, each subgingival root surface was irrigated with approximately 10ml for 1 minute either with TTC HCl 10% solution (test, or Aquabides solution (control. The clinical parameters were assessed at baseline and weeks 3. The two sites resulted in significant statistical and clinical improvement in all parameters. BOP was not significantly reduced in test site compared to control site. PPD and LA was significantly reduced at test site compared to control site. The result indicate that subgingival irrigation with TTC HCl 10% solution 10ml for 1 minute may have a role in the management of moderate CAP. This treatment reduces surgical needs.

  16. SINTESIS DIMETIL ASETAL SITRONELAL DENGAN KATALIS GAS HCL

    Directory of Open Access Journals (Sweden)

    E Cahyono

    2014-06-01

    Full Text Available Perlindungan gugus aldehida melalui pembentukan asetal umumnya dilakukan dengan metanol atau etanol terkatalis asam. Sitronelal memiliki gugus aldehida dan gugus alkena. Dalam lingkungan asam, sitronelal mudah mengalami siklisasi membentuk isopulegol dan isomernya. Penelitian ini bertujuan untuk mensintesis dimetil asetal sitronelal dengan katalis gas HCl. Penggunaan gas HCl secara terbatas dimaksudkan untuk menghindari siklisasi sitronelal. Dalam suatu reaktor, 10 mL sitronelal ditambah dengan 20 mL metanol absolut dan 2 g CaCl2 pada labu leher tiga. Gas HCl dialirkan dengan laju alir 12 mL/menit pada temperatur ruang hingga pH campuran menjadi 2-3. Kemudian dilakukan pengadukan pada 30°C selama 48 jam dan diambil sampel pada durasi reaksi 12, 24 dan 48 jam. Dalam penelitian ini dilakukan variasi temperatur dan jumlah CaCl2. Dimetil asetal sitronelal yang dihasilkan diisolasi dengan distilasi fraksinasi pengurangan tekanan dan diuji strukturnya dengan GC-MS, IR dan 1H-NMR. Peningkatan temperatur dan jumlah CaCl2 meningkatkan konversi sitronelal. Setelah 48 jam kuantitas dimetil asetal sitronelal mencapai 48,65%. Distilasi fraksinasi pengurangan tekanan (5 cmHg terbukti meningkatkan kemurnian dimetil asetal sitronelal menjadi 86,39% terhadap produk kasarnya. Elusidasi struktur dengan spektrofotometer infra merah (IR dan resonansi magnetik inti (1H-NMR pada hasil distilasi fraksinasi membuktikan adanya struktur asetal sitronelal.  Aldehyde group protection through acetal formation is generally performed by acid catalyzed methanol or ethanol. Citronellal that has aldehyde and alkene groups. In acidic environment, it is prone to do cyclization to form isopulegol and its isomers. This study aims to synthesize dimethyl acetal of citronellal with HCl gas catalysts. The limitation of HCl using gas was intended to avoid the citronellal cyclization. In a reactor, 10 mL citronellal was added with 20 mL of absolute methanol and 2 g CaCl2 in the three

  17. New promising antifouling agent based on polymeric biocide polyhexamethylene guanidine molybdate.

    Science.gov (United States)

    Protasov, Alexander; Bardeau, Jean-Francois; Morozovskaya, Irina; Boretska, Mariia; Cherniavska, Tetiana; Petrus, Lyudmyla; Tarasyuk, Oksana; Metelytsia, Larisa; Kopernyk, Iryna; Kalashnikova, Larisa; Dzhuzha, Oleg; Rogalsky, Sergiy

    2017-09-01

    A new polymeric biocide polyhexamethylene guanidine (PHMG) molybdate has been synthesized. The obtained cationic polymer has limited water solubility of 0.015 g/100 mL and is insoluble in paint solvents. The results of acute toxicity studies indicate moderate toxicity of PHMG molybdate, which has a median lethal dose at 48 h of 0.7 mg/L for Daphnia magna and at 96 h of 17 mg/L for Danio rerio (zebrafish) freshwater model organisms. Commercial ship paint was then modified by the addition of a low concentration of polymeric biocide 5% (w/w). The painted steel panels were kept in Dnipro River water for the evaluation of the dynamics of fouling biomass. After 129-d exposure, Bryozoa dominated in biofouling of tested substrates, forming 86% (649 g/m 2 ) of the total biomass on control panel surfaces. However, considerably lower Bryozoa fouling biomass (15 g/m 2 ) was detected for coatings containing PHMG molybdate. Dreissenidae mollusks were found to form 88% (2182 g/m 2 ) of the fouling biomass on the control substrates after 228 d of exposure, whereas coatings containing PHMG molybdate showed a much lower biomass value of 23.6 g/m 2 . The leaching rate of PHMG molybdate in water was found to be similar to rates for conventional booster biocides ranging from 5.7 μg/cm 2 /d at the initial stage to 2.2 μg/cm 2 /d at steady state. Environ Toxicol Chem 2017;36:2543-2551. © 2017 SETAC. © 2017 SETAC.

  18. Marjoram Extract as Corrosion Inhibitor for Dissolution of Zinc in 1.0 M HCl

    Directory of Open Access Journals (Sweden)

    M. Sobhi

    2013-01-01

    Full Text Available In this study, water marjoram (Origanum marjorana L. extract was evaluated as corrosion inhibitor for zinc in 1.0 M HCl solution. The polarization measurements showed that this inhibitor is acting as mixed inhibitors for both anodic and cathodic reactions. The results showed that the inhibition efficiency was increased by increasing the inhibitor doses and reached the maximum at 500 ppm. The adsorption of marjoram extract on zinc surface was found to obey Langmuir type isotherm. The efficiency obtained from the impedance measurements was in good agreement with those obtained from the gravimetrical, thermometric, and polarization techniques which prove the validity of these tolls in the measurements of the tested inhibitor.

  19. Discovery and structure-activity relationships of (2-(arylthio)benzylideneamino)guanidines as a novel series of potent apoptosis inducers.

    Science.gov (United States)

    Zhang, Han-Zhong; Crogan-Grundy, Candace; May, Chris; Drewe, John; Tseng, Ben; Cai, Sui Xiong

    2009-04-01

    1-(2-(2,5-Dimethoxyphenylthio)benzylidene)semicarbazide (2a) was discovered as a potent apoptosis inducer through our cell based HTS assay. SAR study led to the discovery of a more aqueous soluble analog (2-(2,5-dimethoxyphenylthio)-6-methoxybenzylideneamino)guanidine (5e) with EC(50) value of 60 nM in the caspase activation assay and GI(50) value of 62 nM in the growth inhibition assay in T47D cells. Compound 5e was found to be an inhibitor of tubulin polymerization and efficacious in a MX-1 breast tumor model.

  20. Sigma receptor ligand N,N'-di-(ortho-tolyl)guanidine inhibits release of acetylcholine in the guinea pig ileum.

    Science.gov (United States)

    Cambell, B G; Keana, J F; Weber, E

    1991-11-26

    The inhibition of stimulated contractions of the guinea pig ileum longitudinal muscle/myenteric plexus preparation by sigma receptor ligands has been previously described. In this study, the stimulated release of [3H]acetylcholine from cholinergic nerve terminals in this same preparation was monitored in the presence and absence of sigma receptor ligands. N,N'-Di-(orthotolyl)guanidine (DTG) and other compounds selective for the sigma receptor inhibited stimulated [3H]acetylcholine release. These results suggest that their inhibition of stimulated contractions in this preparation was mediated by inhibition of acetylcholine release.

  1. Thermodynamic modeling of ternary and quaternary (liquid + liquid) systems containing water, FeCl3, HCl and diisopropyl ether

    International Nuclear Information System (INIS)

    Milosevic, Miran; Hendriks, Ilse; Smits, Ralph E.R.; Schuur, Boelo; Haan, André B. de

    2013-01-01

    Highlights: • Literature data from various sources was validated experimentally. • Ternary and quaternary (liquid + liquid) systems were successfully described with the NRTL model. • Some deflection at higher HCl concentrations between model and data. • Additional data verification proved correctness of the literature data. -- Abstract: Liquid–liquid extraction using ethers as solvents is a potentially energy saving alternative for the concentration of aqueous ferric chloride solutions. Adequate thermodynamic models that describe the behavior of the resulting quaternary systems (FeCl 3 , ether, acid and water) are not available in the literature. In this paper, the development of an equilibrium description applying the NRTL-model is presented, including experimental validation and fitting of the NRTL-parameters on the validated data. Equilibrium experiments were performed for the ternary systems (water + HCl + DiPE) and (water + FeCl 3 + DiPE) and the obtained data is in good agreement with the results from Maljkovic et al.[37] and Cambell et al.[39]. Experimental data of the quaternary system is taken from Maljkovic et al.[37]. The obtained binary interaction parameters to describe the (liquid + liquid) quaternary system (water + FeCl 3 + HCl + DiPE) and the constituting ternaries by the NRTL model are presented. Model predictions are in good agreement with the experimental data

  2. Fragmentation of HCl following excitation at the chlorine K edge

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, D.L.; Arrasate, M.E. [Univ. of Nevada, Las Vegas, NV (United States); Cotter, J.P. [Univ. of Nevada, Reno, NV (United States)] [and others

    1997-04-01

    A space-focused time-of-flight (TOF) mass spectrometer was used to study the relaxation dynamics of HCl following excitation in the vicinity of the Cl-K edge ({approximately}2.8 keV) using x-rays from B.L. 9.3.1. At the lowest resonant excitation to a {sigma}{sup *} antibonding orbital (1{sigma} {r_arrow} 6{sigma}), a significant fraction of the excited molecules decay by emission of a neutral H atom. While neutral-H emission has been observed for shallow core levels (e.g., Cl 2p in HCl), the authors believe this to be the first observation of neutral-atom emission as a significant decay channel following resonant excitation of a deep core hole. The dissociation of neutral hydrogen atoms raises the issue of how effectively dissociation competes with Auger decay in the relaxation of these deep core levels (i.e., Cl 1s). Graphical evidence is presented to support the dissociation agrument. In addition, trends in fractional ion yields from Photo-Ion Photo-Ion COincidence (PIPICO) spectra suggest the presence of post-collision interaction (PCI). While, electron spectroscopy studies are required to confirm the observation of this effect, the authors believe this to be the first evidence of PCI moderated dissociation in molecules.

  3. Reaction kinetics of nitrous acid with acetohydroxamic acid in HClO4 and HNO3 medium

    International Nuclear Information System (INIS)

    Zheng Weifang; Yan Taihong; Bian Xiaoyan; Zhang Yu

    2007-01-01

    The presence of nitrous acid in feed solution of PUREX process is unavoidable. Owing to its effect on the valence of plutonium and other nuclides, nitrous acid should be scavenged. The kinetics of reaction of AHA with nitrous acid was studied in HClO 4 and HNO 3 medium. The reaction rate equation in HClO 4 and HNO 3 medium is obtained as. --dc(HNO 2 )/dr= k·c(HNO 2 ) 1 ·c(AHA) 0.75 ·c(HClO 4 ) 0.5 and --dc(HNO 2 )/dt=k·c(HNO 2 ) 1 ·c(AHA) 0.25 .· c(HNO 3 ) 1 , respectively. In HClO 4 medium, the reaction rate constant (k) is found to be (2.37±0.21) L 1.25 /(mol 1.25 ·s) at θ=5 degree C, I=0.5 mol/kg. Reaction rate constant is increased slightly with the increased ion strength in the range of 0.5-2.0 mol/kg. In HNO 3 medium, the reaction rate constant (k) is found to be (0.482±0.048) L 1.25 /(mol 1.25 ·s) at θ=10 degree C and I= 0.5 mol/kg. Reaction rate constant is also increased slightly with the increased ion strength in the range of 0.5-3.0 mol/kg. The effect of temperature to the reaction rate is also studied. The results show that with the increase of temperature, the reaction rate increases quickly. And the activation energy is found to be 99.0 kJ/mol and 46.9 kJ/mol respectively in HNO 3 . (authors)

  4. Effect of HCl Loading and Ethanol Concentration over HCl-Activated Clay Catalysts for Ethanol Dehydration to Ethylene.

    Science.gov (United States)

    Krutpijit, Chadaporn; Jongsomjit, Bunjerd

    2017-01-01

    Montmorillonite clay (MMT) is one of materials that can be "green material" due to its environmental safety. In this work, acid-activated MMT catalysts were prepared for the dehydration reaction of ethanol. To be the green process, the reaction with bioethanol was also studied. Ethanol concentrations in feed were varied in the range of 10-99.95 wt%. Moreover, the concentrations of hydrochloric acid activated MMT were investigated in range of 0.05-4 M. From the experiment, it reveals that different acid concentrations to activate MMT affect the catalytic activity of catalysts. The 0.3 M of HCl activated MMT exhibits the highest activity (under the best condition of 30 ml HCl aging for 1 h) with the Si/Al ratio of 7.4. It can reach the ethanol conversion and ethylene selectivity up to 95% and 98% at reaction temperature of 400°C, respectively. For the several ethanol feed concentrations, it does not remarkably affect in ethanol conversion. However, it has some different effect on ethylene selectivity between lower and higher reaction temperatures. It was found that at lower temperature reaction, ethylene selectivity is high due to the behavior of water in feed. In addition, the 0.3 M-MMT can be carried out under the hydrothermal effect.

  5. Human exposure to polyhexamethylene guanidine phosphate from humidifiers in residential settings: Cause of serious lung disease.

    Science.gov (United States)

    Lee, Ji Hyun; Yu, Il Je

    2017-11-01

    Exposure to the humidifier disinfectant, polyhexamethylene guanidine phosphate (PHMG), in mists generated from ultrasonic humidifiers was studied in a simulation chamber and apartment rooms. PHMG is suspected as a causative agent of lung disease in Korea residences. In the simulation-chamber study, the amount of disinfectant discharged from three different ultrasonic humidifiers was measured. Mists generated at 1, 2, and 4 times the recommended amount of disinfectant were sampled with an impinger, and the effect of relative humidity (RH) on airborne disinfectant concentration was studied by changing RH from 60%-70% to 90%-100%. In addition, particle size distribution (PSD) in mists was measured by scanning mobility particle sizer (SMPS), aerodynamic particle sizer (APS), and Mastersizer. In the apartment study, mists generated from ultrasonic humidifiers were sampled for 6 h in small and large rooms during fall ( n = 10) and winter ( n = 15). In the simulation study, the humidifiers discharged 205 ± 24.6 ml/h of mist at maximum capacity. Concentrations of airborne disinfectant increased with increasing concentration of disinfectant. RH affected airborne disinfectant concentration in the chamber, with increasing concentration with increasing RH. Below RH 70%, no airborne PHMG was detected. PHMG-containing mists generated from ultrasonic humidifier showed various sizes ranging from 149-157 nm to 690-740 nm to larger than 5.4 µm by SMPS, APS, and Mastersizer, respectively. Surface area mean diameter measured by Mastersizer ranged from 5.39 µm to 5.72 µm. In the apartment study conducted during the fall, the geometric mean (GM) and geometric standard deviation (GSD) and arithmetic mean (AM) and standard deviation (SD) of airborne PHMG concentration were 3.22 + 5.13 µg/m 3 and 8.26 ± 12.18 µg/m 3 , respectively. In the winter, GM + GSD and AM ± SD of airborne PHMG concentration were 0.21 + 2.11 µg/m 3 and 0.35 ± 0.62 µg/m 3 , respectively. RH and temperature

  6. Polyhexamethylene guanidine phosphate aerosol particles induce pulmonary inflammatory and fibrotic responses.

    Science.gov (United States)

    Kim, Ha Ryong; Lee, Kyuhong; Park, Chang We; Song, Jeong Ah; Shin, Da Young; Park, Yong Joo; Chung, Kyu Hyuck

    2016-03-01

    Polyhexamethylene guanidine (PHMG) phosphate was used as a disinfectant for the prevention of microorganism growth in humidifiers, without recognizing that a change of exposure route might cause significant health effects. Epidemiological studies reported that the use of humidifier disinfectant containing PHMG-phosphate can provoke pulmonary fibrosis. However, the pulmonary toxicity of PHMG-phosphate aerosol particles is unknown yet. This study aimed to elucidate the toxicological relationship between PHMG-phosphate aerosol particles and pulmonary fibrosis. An in vivo nose-only exposure system and an in vitro air-liquid interface (ALI) co-culture model were applied to confirm whether PHMG-phosphate induces inflammatory and fibrotic responses in the respiratory tract. Seven-week-old male Sprague-Dawley rats were exposed to PHMG-phosphate aerosol particles for 3 weeks and recovered for 3 weeks in a nose-only exposure chamber. In addition, three human lung cells (Calu-3, differentiated THP-1 and HMC-1 cells) were cultured at ALI condition for 12 days and were treated with PHMG-phosphate at set concentrations and times. The reactive oxygen species (ROS) generation, airway barrier injuries and inflammatory and fibrotic responses were evaluated in vivo and in vitro. The rats exposed to PHMG-phosphate aerosol particles in nanometer size showed pulmonary inflammation and fibrosis including inflammatory cytokines and fibronectin mRNA increase, as well as histopathological changes. In addition, PHMG-phosphate triggered the ROS generation, airway barrier injuries and inflammatory responses in a bronchial ALI co-culture model. Those results demonstrated that PHMG-phosphate aerosol particles cause pulmonary inflammatory and fibrotic responses. All features of fibrogenesis by PHMG-phosphate aerosol particles closely resembled the pathology of fibrosis that was reported in epidemiological studies. Finally, we expected that PHMG-phosphate infiltrated into the lungs in the form of

  7. THE HIGH-RESOLUTION INFRARED SPECTRUM OF HCl{sup +}

    Energy Technology Data Exchange (ETDEWEB)

    Doménech, J. L.; Herrero, V. J.; Tanarro, I. [Molecular Physics Department, Instituto de Estructura de la Materia (IEM-CSIC), Serrano 123, E-28006 Madrid (Spain); Drouin, B. J. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109-8099 (United States); Cernicharo, J., E-mail: jl.domenech@csic.es [Molecular Astrophysics Group, Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC), Sor Juana Inés de la Cruz 3, Cantoblanco, E-28049 Madrid (Spain)

    2016-12-20

    The chloroniumyl cation, HCl{sup +}, has been recently identified in space from Herschel 's spectra. A joint analysis of extensive vis-UV spectroscopy emission data together with a few high-resolution and high-accuracy millimeter-wave data provided the necessary rest frequencies to support the astronomical identification. Nevertheless, the analysis did not include any infrared (IR) vibration–rotation data. Furthermore, with the end of the Herschel mission, IR observations from the ground may be one of the few available means to further study this ion in space. In this work, we provide a set of accurate rovibrational transition wavenumbers, as well as a new and improved global fit of vis-UV, IR, and millimeter-wave spectroscopy laboratory data, that will aid in future studies of this molecule.

  8. Bicyclic Guanidine Catalyzed Asymmetric Tandem Isomerization Intramolecular-Diels-Alder Reaction: The First Catalytic Enantioselective Total Synthesis of (+)-alpha-Yohimbine.

    Science.gov (United States)

    Feng, Wei; Jiang, Danfeng; Kee, Choon-Wee; Liu, Hongjun; Tan, Choon-Hong

    2016-02-04

    Hydroisoquinoline derivatives were prepared in moderate to good enantioselectivities via a bicyclic guanidine-catalyzed tandem isomerization intramolecular-Diels-Alder (IMDA) reaction of alkynes. With this synthetic method, the first enantioselective synthesis of (+)-alpha-yohimbine was completed in 9 steps from the IMDA products. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Analysis of the critical step in catalytic carbodiimide transformation: proton transfer from amines, phosphines, and alkynes to guanidinates, phosphaguanidinates, and propiolamidinates with Li and Al catalysts.

    Science.gov (United States)

    Rowley, Christopher N; Ong, Tiow-Gan; Priem, Jessica; Richeson, Darrin S; Woo, Tom K

    2008-12-15

    While lithium amides supported by tetramethylethylenediamine (TMEDA) are efficient catalysts in the synthesis of substituted guanidines via the guanylation of an amine with carbodiimide, as well as the guanylation of phosphines and conversion of alkynes into propiolamidines, aluminum amides are only efficient catalysts for the guanylation of amides. Density functional theory (DFT) calculations were used to explain this difference in activity. The origin of this behavior is apparent in the critical step where a proton is transferred from the substrate to a metal guanidinate. The activation energies of these steps are modest for amines, phosphines, and alkynes when a lithium catalyst was used, but are prohibitively high for the analogous reactions with phosphines and alkynes for aluminum amide catalysts. Energy decomposition analysis (EDA) indicates that these high activations energies are due to the high energetic cost of the detachment of a chelating guanidinate nitrogen from the aluminum in the proton transfer transition state. Amines are able to adopt an ideal geometry for facile proton transfer to the aluminum guanidinate and concomitant Al-N bond formation, while phosphines and alkynes are not.

  10. Sampling the Denatured State of Polypeptides in Water, Urea, and Guanidine Chloride to Strict Equilibrium Conditions with the Help of Massively Parallel Computers.

    Science.gov (United States)

    Meloni, Roberto; Camilloni, Carlo; Tiana, Guido

    2014-02-11

    The denatured state of polypeptides and proteins, stabilized by chemical denaturants like urea and guanidine chloride, displays residual secondary structure when studied by nuclear-magnetic-resonance spectroscopy. However, these experimental techniques are weakly sensitive, and thus molecular-dynamics simulations can be useful to complement the experimental findings. To sample the denatured state, we made use of massively-parallel computers and of a variant of the replica exchange algorithm, in which the different branches, connected with unbiased replicas, favor the formation and disruption of local secondary structure. The algorithm is applied to the second hairpin of GB1 in water, in urea, and in guanidine chloride. We show with the help of different criteria that the simulations converge to equilibrium. It results that urea and guanidine chloride, besides inducing some polyproline-II structure, have different effect on the hairpin. Urea disrupts completely the native region and stabilizes a state which resembles a random coil, while guanidine chloride has a milder effect.

  11. Densities and apparent molar volumes of HClO4(aq) and Yb(ClO4)3(aq) at elevated temperatures and pressures

    International Nuclear Information System (INIS)

    Hakin, Andrew W.; Lukacs, Michael J.; Jin Lianliu

    2004-01-01

    Relative densities have been measured for acidified aqueous solutions of ytterbium perchlorate {Yb(ClO 4 ) 3 } at approximately T=(348.15, 373.15, 398.15, and 423.15) K and p=(10.0, 20.0, and 30.0) MPa over the concentration range 0.01624≤m 2 /(mol · kg -1 ) ≤ 0.2531 using an optically coupled vibrating tube densimeter (OCVTD). Experimental apparent molar volumes have been calculated from the density measurements, and apparent molar volumes for the aqueous perchlorate salt have been calculated using Young's rule. The application of Young's rule requires apparent molar volumes for aqueous perchloric acid (HClO 4 ) solutions over extended temperature and pressure ranges. These values were calculated from densities for aqueous HClO 4 solutions that were measured using the OCVTD at the same temperatures and pressures as those used to investigate the density surface of the acidified aqueous Yb(ClO 4 ) 3 solutions. The temperature, pressure, and composition surfaces of the apparent molar volumes for Yb(ClO 4 ) 3 (aq) and HClO 4 (aq) have been modelled using Pitzer ion-interaction equations. Apparent molar volumes at infinite dilution obtained from these models have been compared to those which can be calculated using the semi-empirical Helgeson, Kirkham, and Flowers equations of state. Values for the apparent molar volume at infinite dilution of the ytterbium trivalent cation have also been calculated using simple additivity principles

  12. Effect of HCl Concentration on the Oxidation of LIX 63 and the Subsequent Separation of Pd(II), Pt(IV), Ir(IV) and Rh(III) by Solvent Extraction

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Thi Hong; Lee, Man Seung [Mokpo National University, Jeollanamdo (Korea, Republic of)

    2016-10-15

    During the selective extraction of Pd(II) by LIX 63 from 6 M HCl solutions containing platinum group metals, an oxidation-reduction reaction occurs between the LIX 63 and Ir(IV). Since the reduced Ir(III) cannot be extracted by solvating and amine extractants, the oxidation-reduction reaction has a significant effect on the separation of Pt(IV), Ir(IV) and Rh(III). Therefore, the effect of HCl concentration on the reduction of Ir(IV) during the extraction with LIX 63 was investigated at 3 and 6 M HCl solutions. The extraction behavior of Iridium by Aliquat 336 from the Pd(II) free raffinate showed that the percentage of iridium extraction rapidly decreased when HCl concentration was increased from 3 to 6 M, indicating that more Ir(IV) was reduced to Ir(III). Extraction schemes for the separation of Pt(IV), iridium and Rh(III) by Aliquat 336 from 3 and 6 M HCl solutions were investigated.

  13. From items to syndromes in the Hypomania Checklist (HCL-32): Psychometric validation and clinical validity analysis

    DEFF Research Database (Denmark)

    Bech, P; Christensen, E M; Vinberg, M

    2011-01-01

    BACKGROUND: The Hypomania Checklist (HCL-32) was developed to identify subthreshold bipolarity in patients with major depression. An HCL-32 version with fewer items has been suggested. METHODS: Principal component analysis (PCA) without rotation was used to identify active/elevated mood versus ri...

  14. Anticoccidial activity of hydrochloric acid (HCl against Eimeria tenella in broiler chickens

    Directory of Open Access Journals (Sweden)

    Rao Z Abbas

    2011-05-01

    Full Text Available The present study was planned to evaluate the anticoccidial activity of the different concentrations of the HCl against Eimeria tenella infection in broiler chickens in comparison with the amprolium anticoccidial. For this purpose, a total of 198 chicks were placed 11 per pen with three pens per treatment. The different concentrations of HCl (1000ppm, 2000ppm and 3000ppm and amproilum (at the dose rate of 125ppm were given to the experimental groups in drinking water from 10 to 19th days of age. One group was kept as infected non medicated control and one as non infected non medicated control. At the 12th day of age, all the groups were inoculated orally with 75,000 sporulated oocysts except non infected non medicated control. Anticoccidial activity was evaluated on the basis of performance (weight gain, feed conversion ratio and pathogenic (oocyst score, lesion score and mortality %age parameters. Among HCl medicated groups, the maximum anticoccidial effect was seen in the group medicated with 1000ppm HCl followed by 2000ppm and 3000ppm HCl medicated groups. Amprolium and 1000ppm HCl were almost equivalent in suppressing the negative performance and pathogenic effects associated with coccidiosis (Eimeria tenella challenge. In summary, the lower doses of HCl have the potential to be used as alternative to chemotherapeutic drugs for Eimeria tenella control. It is therefore suggested that further studies should be carried out to determine the possible minimum safe levels of HCl with least toxic effects to be used as anticoccidial.

  15. A Safe and Efficient Technique for the Production of HCl/DCl Gas

    Science.gov (United States)

    Mayer, Steven G.; Bard, Raymond R.; Cantrell, Kevin

    2008-01-01

    We present a safe and efficient technique to generate HCl/DCl gas for use in the classic physical chemistry experiment that introduces students to ro-vibrational spectroscopy. The reaction involves thionyl chloride and a mixture of water and deuterium oxide to produce HCl/DCl gas with SO[subscript 2] gas as a byproduct. The entire reaction is…

  16. Characterization of two clays - attapulgite and sepiolite - before and after acid activation; Caracterizacao de duas argilas - atapulgita e sepiolita - antes e apos ativacao acida com HCl

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, R.N.; Soares, G.A., E-mail: renataoliveira@poli.ufrj.b [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Centro de Tecnologia; Barreto, L.S. [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil)

    2009-07-01

    Among the special clays, two of them are distinguished by their large surface area: attapulgite and sepiolite. Although, being natural clays, when they are removed from the formation sites, their structural channels may be filled of impurities. The process done to clean these channels is called acid activation. The present work aim to treated samples from both clays by using 3M and 5M HCl solution under ultrasonic waves for 1 hour. The characterization of the clays before and after activation was carried out by SEM/EDS, XRD and surface area measure by method BET. The acid treatments employed were too aggressive, in special that with 5M HCl solution, which results in partial lixiviation of these clays. (author)

  17. A chiral analog of the bicyclic guanidine TBD: synthesis, structure and Brønsted base catalysis

    Directory of Open Access Journals (Sweden)

    Mariano Goldberg

    2016-08-01

    Full Text Available Starting from (S-β-phenylalanine, easily accessible by lipase-catalyzed kinetic resolution, a chiral triamine was assembled by a reductive amination and finally cyclized to form the title compound 10. In the crystals of the guanidinium benzoate salt the six membered rings of 10 adopt conformations close to an envelope with the phenyl substituents in pseudo-axial positions. The unprotonated guanidine 10 catalyzes Diels–Alder reactions of anthrones and maleimides (25–30% ee. It also promotes as a strong Brønsted base the retro-aldol reaction of some cycloadducts with kinetic resolution of the enantiomers. In three cases, the retro-aldol products (48–83% ee could be recrystallized to high enantiopurity (≥95% ee. The absolute configuration of several compounds is supported by anomalous X-ray diffraction and by chemical correlation.

  18. The effect of polyhexamethylene guanidine hydrochloride (PHMG) derivatives introduced into polylactide (PLA) on the activity of bacterial enzymes.

    Science.gov (United States)

    Walczak, Maciej; Richert, Agnieszka; Burkowska-But, Aleksandra

    2014-11-01

    The present study was aimed at investigating bactericidal properties of polylactide (PLA) films containing three different polyhexamethylene guanidine hydrochloride (PHMG) derivatives and effect of the derivatives on extracellular hydrolytic enzymes and intracellular dehydrogenases. All PHMG derivatives had a slightly stronger bactericidal effect on Staphylococcus aureus than on E. coli but only PHMG granular polyethylene wax (at the concentration of at least 0.6 %) has a bactericidal effect. PHMG derivatives introduced into PLA affected the activity of microbial hydrolases to a small extent. This means that the introduction of PHMG derivatives into PLA will not reduce its enzymatic biodegradation significantly. On the other hand, PHMG derivatives introduced into PLA strongly affected dehydrogenases activity in S. aureus than in E. coli.

  19. Blood-brain transfer and antinociception of linear and cyclic N-methyl-guanidine and thiourea-enkephalins

    DEFF Research Database (Denmark)

    Verbeken, Mathieu; Wynendaele, Evelien; Mauchauffee, Elodie

    2015-01-01

    Enkephalins are active in regulation of nociception in the body and are key in development of new synthetic peptide analogs that target centrally located opioid receptors. In this study, we investigated the in vivo blood–brain barrier (BBB) penetration behavior and antinociceptive activity of two...... cyclic enkephalin analogs with a thiourea (CycS) or a N-methyl-guanidine bridge (CycNMe), and their linear counterparts (LinS and LinNMe) in mice, as well as their in vitro metabolic stability. 125I-LinS had the highest blood–brain clearance (K1 = 3.46 μL/g min), followed by 125I-LinNMe, 125I...

  20. Resistance of various coatings to high temperature corrosion in HCl and SO{sub 2} containing environments

    Energy Technology Data Exchange (ETDEWEB)

    Cizner, Josef; Mlnarik, Jakub; Hruska, Jan [SVUM a.s., Prague (Czech Republic). Lab. of High Temperature Corrosion

    2010-07-01

    For high efficiency of the steam turbines it is necessary to produce steam of temperature at least 400 C, which in conjunction with specific composition of combustion gases causes fireside corrosion problems. The combustion gases contain aggressive compounds ike HCl and SO{sub 2} and some other elements which can form deposits on heat exchanging surfaces e.g. calcium, potassium salts etc. Using of high-alloy steels or nickel-based alloys is very costly and also these materials could have lower thermal conductivity. A cheaper solution is to produce a coating on low (medium)-alloy steel. Common heat-resistant steels show very short lifetime under these conditions. The solution is then to use the appropriate coatings. Some types of coatings can be applied even inside older boilers. In this work we tested many coatings composition (nickel-based, aluminium-based etc. As well as with different processing method - arc sprayed coating, weld deposits, HVOF, etc.) on 16Mo3 steel. In particular their high temperature corrosion behaviour in model atmosphere containing SO{sub 2} and HCl and also under deposit of fly ash was studied. (orig.)

  1. (Vapour+liquid) equilibria of {xCH3Cl+(1-x)HCl} at temperatures (159.01 and 182.33) K

    International Nuclear Information System (INIS)

    Senra, A.M.P.; Fonseca, I.M.A.; Lobo, L.Q.

    2005-01-01

    VLE for (CH 3 Cl+HCl) has been experimentally determined at temperatures (159.01 and 182.33) K, using a static; method. The data were used to calculate the molar excess Gibbs energy at the two temperatures. The excess molar enthalpy estimated from the G m E values for the equimolar mixture is relatively large and negative: H m E =-(1011+/-318) J.mol -1 . The results have been compared with estimates from the chemical theory of solutions

  2. Spin-rotation and NMR shielding constants in HCl

    Energy Technology Data Exchange (ETDEWEB)

    Jaszuński, Michał, E-mail: michal.jaszunski@icho.edu.pl [Institute of Organic Chemistry, Polish Academy of Sciences, 01-224 Warszawa, Kasprzaka 44 (Poland); Repisky, Michal; Demissie, Taye B.; Komorovsky, Stanislav; Malkin, Elena; Ruud, Kenneth [Centre for Theoretical and Computational Chemistry, University of Tromsø—The Arctic University of Norway, N-9037 Tromsø (Norway); Garbacz, Piotr; Jackowski, Karol; Makulski, Włodzimierz [Laboratory of NMR Spectroscopy, Department of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw (Poland)

    2013-12-21

    The spin-rotation and nuclear magnetic shielding constants are analysed for both nuclei in the HCl molecule. Nonrelativistic ab initio calculations at the CCSD(T) level of approximation show that it is essential to include relativistic effects to obtain spin-rotation constants consistent with accurate experimental data. Our best estimates for the spin-rotation constants of {sup 1}H{sup 35}Cl are C{sub Cl}  = −53.914 kHz and C{sub H}  = 42.672 kHz (for the lowest rovibrational level). For the chlorine shielding constant, the ab initio value computed including the relativistic corrections, σ(Cl) = 976.202 ppm, provides a new absolute shielding scale; for hydrogen we find σ(H) = 31.403 ppm (both at 300 K). Combining the theoretical results with our new gas-phase NMR experimental data allows us to improve the accuracy of the magnetic dipole moments of both chlorine isotopes. For the hydrogen shielding constant, including relativistic effects yields better agreement between experimental and computed values.

  3. Spin-rotation and NMR shielding constants in HCl

    International Nuclear Information System (INIS)

    Jaszuński, Michał; Repisky, Michal; Demissie, Taye B.; Komorovsky, Stanislav; Malkin, Elena; Ruud, Kenneth; Garbacz, Piotr; Jackowski, Karol; Makulski, Włodzimierz

    2013-01-01

    The spin-rotation and nuclear magnetic shielding constants are analysed for both nuclei in the HCl molecule. Nonrelativistic ab initio calculations at the CCSD(T) level of approximation show that it is essential to include relativistic effects to obtain spin-rotation constants consistent with accurate experimental data. Our best estimates for the spin-rotation constants of 1 H 35 Cl are C Cl   = −53.914 kHz and C H   = 42.672 kHz (for the lowest rovibrational level). For the chlorine shielding constant, the ab initio value computed including the relativistic corrections, σ(Cl) = 976.202 ppm, provides a new absolute shielding scale; for hydrogen we find σ(H) = 31.403 ppm (both at 300 K). Combining the theoretical results with our new gas-phase NMR experimental data allows us to improve the accuracy of the magnetic dipole moments of both chlorine isotopes. For the hydrogen shielding constant, including relativistic effects yields better agreement between experimental and computed values

  4. Stratospheric chlorine injection by volcanic eruptions - HCl scavenging and implications for ozone

    Science.gov (United States)

    Tabazadeh, A.; Turco, R. P.

    1993-01-01

    Because the output of volatile chlorine during a major volcanic event can greatly exceed the annual anthropogenic emissions of chlorine to the atmosphere, the fate of volcanic chlorine must be known. Although numerous observations have shown that volcanoes do not significantly contribute to the stratospheric chlorine burden, no quantitative explanation has been published. Hydrogen chloride (HCl) scavenging processes during the early phases of a volcanic eruption are discussed. A plume dynamics and thermodynamics model is used to show that HCl removal in condensed supercooled water can reduce HCl vapor concentrations by up to four orders of magnitude, preventing substantial stratospheric chlorine injection.

  5. Enhancing fluorescence intensity of Ellagic acid in Borax-HCl-CTAB micelles

    Science.gov (United States)

    Wang, Feng; Huang, Wei; Zhang, Shuai; Liu, Guokui; Li, Kexiang; Tang, Bo

    2011-03-01

    Ellagic acid (C 14H 6O 8), a naturally occurring phytochemical, found mainly in berries and some nuts, has anticarcinogenic and antioxidant properties. It is found that fluorescence of Ellagic acid (EA) is greatly enhanced by micelle of cetyltrimethylammonium bromide (CTAB) surfactant. Based on this effect, a sensitive proposed fluorimetric method was applied for the determination of Ellagic acid in aqueous solution. In the Borax-HCl buffer, the fluorescence intensity of Ellagic acid in the presence of CTAB is proportional to the concentration of Ellagic acid in range from 8.0 × 10 -10 to 4.0 × 10 -5 mol L -1; and the detection limits are 3.2 × 10 -10 mol L -1 and 5.9 × 10 -10 mol L -1 excited at 266 nm and 388 nm, respectively. The actual samples of pomegranate rinds are simply manipulated and satisfactorily determined. The interaction mechanism studies argue that the negative EA-Borax complex is formed and solubilized in the cationic surfactant CTAB micelle in this system. The fluorescence intensity of EA enhances because the CTAB micelle provides a hydrophobic microenvironment for EA-Borax complex, which can prevent collision with water molecules and decrease the energy loss of EA-Borax complex.

  6. Electrochemical Studies of Monoterpenic Thiosemicarbazones as Corrosion Inhibitor for Steel in 1 M HCl

    Directory of Open Access Journals (Sweden)

    R. Idouhli

    2018-01-01

    Full Text Available We have studied the inhibitory effect of some Monoterpenic Thiosemicarbazones on steel corrosion in 1 M HCl solution. The potentiodynamic polarization and electrochemical impedance spectroscopy were used. The Monoterpenic Thiosemicarbazones have inhibited significantly the dissolution of steel. The inhibition efficiency increased with increasing inhibitor concentration and also with the increase in temperature (293–323 K. Furthermore, the results obtained revealed that the adsorption of inhibitor on steel surface obeys Langmuir adsorption model and the thermodynamic parameters such as enthalpy and activation energy were determined. The scanning electron microscopy combined with dispersive X-ray spectroscopy examinations were used to see the shape of the surface morphology and to determine the elemental composition. Scanning electron microscope (SEM images show that the surface damage decreases when the inhibitor is added. The quantum chemical calculations using density functional theory (DFT were performed in order to provide some insights into the electronic density distribution as well as the nature of inhibitor-steel interaction.

  7. Antifungal drugs as corrosion inhibitors for aluminium in 0.1 M HCl

    Energy Technology Data Exchange (ETDEWEB)

    Obot, I.B. [Department of Chemistry, Faculty of Science, University of Uyo, Uyo (Nigeria)], E-mail: proffoime@yahoo.com; Obi-Egbedi, N.O. [Department of Chemistry, University of Ibadan, Ibadan (Nigeria); Umoren, S.A. [Department of Chemistry, Faculty of Science, University of Uyo, Uyo (Nigeria)

    2009-08-15

    The inhibitive capabilities of Clotrimazole (CTM) and Fluconazole (FLC), two antifungal drugs, on the electrochemical corrosion of aluminium in 0.1 M HCl solution has been studied using weight loss measurements at 30 and 50 deg. C. The results indicate that both compound act as inhibitors in the acidic corrodent. At constant acid concentration, the inhibition efficiency (%I) increased with increase in the concentration of the inhibitors. Increase in temperature increased the corrosion rate in the absence and presence of the inhibitors but decreased the inhibition efficiency. CTM and FLC adsorbed on the surface of aluminium according to the Langmuir adsorption isotherm model at all the concentrations and temperatures studied. Phenomenon of physical adsorption is proposed from the activation parameter obtained. Thermodynamic parameters reveal that the adsorption process is spontaneous. The reactivity of these compounds was analyzed through theoretical calculations based on AM1 semi-empirical method to explain the different efficiencies of these compounds as corrosion inhibitors. CTM was found to be a better inhibitor than FLC.

  8. Evaluation of the Percutaneous Absorption of Ketamine HCl, Gabapentin, Clonidine HCl, and Baclofen, in Compounded Transdermal Pain Formulations, Using the Franz Finite Dose Model.

    Science.gov (United States)

    Bassani, August S; Banov, Daniel

    2016-02-01

    This study evaluates the ability of four commonly used analgesics (ketamine HCl, gabapentin, clonidine HCl, and baclofen), when incorporated into two transdermal compounding bases, Lipoderm and Lipoderm ActiveMax, to penetrate human cadaver trunk skin in vitro, using the Franz finite dose model. In vitro experimental study. Methods. Ketamine HCl 5% w/w, gabapentin 10% w/w, clonidine HCl 0.2% w/w, and baclofen 2% w/w were compounded into two transdermal bases, Lipoderm and Lipoderm ActiveMax. Each compounded drug formulation was tested on skin from three different donors and three replicate skin sections per donor. The Franz finite dose model was used in this study to evaluate the percutaneous absorption and distribution of drugs within each formulation. Rapid penetration to peak flux was detected for gabapentin and baclofen at approximately 1 hour after application. Clonidine HCl also had a rapid penetration to peak flux occurring approximately 1 hour after application and had a secondary peak at approximately 40 hours. Ketamine HCl exhibited higher overall absorption rates than the other drugs, and peaked at 6–10 hours. Similar patterns of drug distribution within the skin were also observed using both transdermal bases. This study suggests that the combination of these 4 analgesic drugs can be successfully delivered transdermally, using either Lipoderm or Lipoderm ActiveMax. Compounded transdermal drug preparations may then provide physicians with an alternative to traditional oral pain management regimens that can be personalized to the specific patient with the potential for enhanced pain control.

  9. Application of phosphating techniques to aluminium and carbon steel surfaces using nitro guanidine as oxidizing agent.; Aplicacion de tecnicas de fosfatacion sobre acero al carbon y aluminio, utilizando como agente oxidante la nitroguanidina.

    Energy Technology Data Exchange (ETDEWEB)

    Briseno M, S A

    1995-10-01

    Phosphate coatings are inorganic crystalline deposits laid down uniformly on properly prepared surfaces by a chemical reaction with the treated base metal. The reaction consists in dissolving some surface metal by acid attack and then causing surface neutralization of the phosphate solution with consequent precipitation of the phosphate coating. Phosphate coatings do not provide appreciable corrosion protection in themselves. They are useful mainly as a base for paints, ensuring good adherence of paint to steel and decreasing the tendency for corrosion to under cut the paint film at scratches or other defects. We deposited phosphate on standard carbon steel, employing techniques of cold phosphate (at 40 Centigrade degrees and with a treatment time of 30 minutes) and hot phosphate (at 88 Centigrade degrees and with a treatment time of 15 minutes), where the latter gave the best results. Both methods used phosphate solutions of Zn/Mn and the catalyst Nitro guanidine. Aluminium surfaces of phosphate were used solutions of Cr and as catalyst Sodium bi fluoride. The phosphating on this surface we deposited at temperature of 50 degrees C with a treatment time of 10 minutes. We obtained a new phosphate coating on steel surfaces, these coatings were realized with a phosphate solution manufactured with the precipitates gathered during the hot phosphating on carbon steel. These coatings show excellent physical characteristics of corrosion resistance. The physical testings of the coatings phosphate obtained on carbon steel and aluminium surfaces. These testing were: roughness, thickness, microhardness and adhesion. The best results were showed in carbon steel phosphate with precipitated solutions. Activation analysis with thermic neutrons was used to determine the phosphate coatings composition. Finally, corrosion testings were realized by means of two methods; electrochemical and by weight loss methods (gravimetric). (Abstract Truncated)

  10. The insulin secretory action of novel polycyclic guanidines: discovery through open innovation phenotypic screening, and exploration of structure-activity relationships.

    Science.gov (United States)

    Shaghafi, Michael B; Barrett, David G; Willard, Francis S; Overman, Larry E

    2014-02-15

    We report the discovery of the glucose-dependent insulin secretogogue activity of a novel class of polycyclic guanidines through phenotypic screening as part of the Lilly Open Innovation Drug Discovery platform. Three compounds from the University of California, Irvine, 1-3, having the 3-arylhexahydropyrrolo[1,2-c]pyrimidin-1-amine scaffold acted as insulin secretagogues under high, but not low, glucose conditions. Exploration of the structure-activity relationship around the scaffold demonstrated the key role of the guanidine moiety, as well as the importance of two lipophilic regions, and led to the identification of 9h, which stimulated insulin secretion in isolated rat pancreatic islets in a glucose-dependent manner. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Development of (acrylic acid/ polyethylene glycol)-zinc oxide mucoadhesive nanocomposites for buccal administration of propranolol HCl

    Science.gov (United States)

    Mahmoud, Ghada A.; Ali, Amr El-Hag; Raafat, Amany I.; Badawy, Nagwa A.; Elshahawy, Mai. F.

    2018-06-01

    A series of mucoadhesive nanocomposites with self disinfection properties composed of acrylic acid, polyethylene glycol and ZnO nanoparticles (AAc/PEG)-ZnO were developed for localized buccal Propranolol HCl delivery. γ-irradiation as a clean tool for graft copolymerization process was used for the preparation of (AAc/PEG) hydrogels. In suite precipitation technique was used for ZnO nanoparticles immobilization within (AAc/PEG) hydrogels. The developed (AAc/PEG)-ZnO nanocomposites were characterized by X-ray diffraction (XRD), UV-Vis spectrophotometer, energy dispersive X-ray spectroscopy (EDX) and scanning electron microscopy (SEM) to confirm the success of ZnO nanoparticles formation within the (AAc/PEG) matrices. The presence of ZnO nanoparticles improves the thermal stability as indicated using thermogravimetric analysis (TGA). The mucoadhesion characteristics such as hydration degree, surface pH, and mucoadhesive strength were evaluated in artificial saliva solution. The self disinfection property of the developed (AAc/PEG)-ZnO nanocomposites was investigated by examining their resistance to pathogenic microorganisms such as Staphylococcus aureus, Bacillus subtilis, and Escherichia coli using disc diffusion method. The release of Propranolol -HCl drug in artificial saliva was found to obey a non-Fickian diffusion mechanism. The obtained results suggests that (AAc/PEG)-ZnO nanocomposites could be used as mucoadhesive carrier for buccal drug delivery with efficient antibacterial properties.

  12. MLS/Aura L2 Hydrogen Chloride (HCl) Mixing Ratio V003

    Data.gov (United States)

    National Aeronautics and Space Administration — ML2HCL is the EOS Aura Microwave Limb Sounder (MLS) standard product for hydrogen chloride derived from radiances measured primarily by the 640 GHz radiometer. The...

  13. MLS/Aura Level 2 Hydrogen Chloride (HCl) Mixing Ratio V004

    Data.gov (United States)

    National Aeronautics and Space Administration — ML2HCL is the EOS Aura Microwave Limb Sounder (MLS) standard product for hydrogen chloride derived from radiances measured primarily by the 640 GHz radiometer. The...

  14. The extraction of uranyl nitrate and chloride in octaethyltetraamidopyrophosphate (OETAPP)-HCl, HNO3 systems

    International Nuclear Information System (INIS)

    Jankowska, M.; Kulawik, J.; Mikulski, J.

    1975-01-01

    The extraction of uranium was studied in the system of 0.1 M OETAPP in CHCl 3 /HCl or HNO 3 . The distribution coefficients of HCl and HNO 3 were calculated as a function of OETAPP concentration. The amount of OETAPP in the aqueous phase containing HCl and HNO 3 was found from the measurements of surface tension of this phase. The distribution of HCl or HNO 3 between the organic and aqueous phases was studied as a function of the concentration of the acid used in the aqueous phase. The solvation energy of the extracted complexes was calculated from the measured potential differences. Cohesion and adhesion energies of the studied systems are also given. (author)

  15. 76 FR 71021 - Formetanate HCl; Amendment to the Use Deletion Cancellation Order

    Science.gov (United States)

    2011-11-16

    ... hard copy, at the Office of Pesticide Programs (OPP) Regulatory Public Docket in Rm. S- 4400, One... things, Formetanate HCl registrants to sell and distribute existing stocks of products under the...

  16. Effect of methanol extract of Prosopis juliflora on mild steel corrosion in 1M HCl

    OpenAIRE

    Zulfareen, Nasarullah; Kannan, Kulanthi; Venugopal, Thiruvengadam

    2016-01-01

    The Prosopis juliflora extract was investigated as a corrosion inhibitor for mild steel in 1M HCl using weight loss measurements, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). The inhibition efficiency of Prosopis juliflora increases with an increase in inhibitor concentration and temperature. Polarization studies revealed that Prosopis juliflora acts as a mixed type inhibitor for mild steel in 1M HCl. AC impedance indicates that the value of charge transfer ...

  17. In-situ complex with by-product HCl and release chloride ions to dissolve aramid.

    Science.gov (United States)

    Dai, Yu; Cheng, Zheng; Yuan, Yihao; Meng, Chenbo; Qin, Jiaqiang; Liu, Xiangyang

    2018-06-20

    Because of the strong hydrogen-bond interaction among macromolecular chains, addition of chloride salts is generally needed to offer Cl- ions for dissolution of aromatic polyamides. In this paper, poly-(benzimidazole-terephthalamide) which complexed with by-product HCl during polymerization (PABI-HCl) was prepared and imidazole compound as cosolvent was added into dimethylacetamide (DMAc) to dissolve PABI-HCl. Due to stronger affinity to protons, imidazole compound could in-situ complex with HCl of PABI-HCl and form imidazolium hydrochloride. Then imidazolium hydrochloride would ionize and produce much free Cl- ions which acted as stronger hydrogen-bond acceptor to disrupt interaction among macromolecular chains. As a result, solubility of PABI-HCl in DMAc was improved significantly in existence of small amount of imidazole compound. Moreover, DMAc-imidazole mixture was utlized for synthesis of different kinds of aramids and no precipitation was observed with progress of the reaction. So the mixture was suitable to be utlized as solvent for polymerization of aramid. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. The study of water + HCl + ethanol vapor-liquid equilibrium at 78 kPa

    International Nuclear Information System (INIS)

    Ojeda Toro, Juan Carlos; Dobrosz-Gómez, Izabela; Gómez García, Miguel Ángel

    2017-01-01

    Graphical abstract: Comparison between experimental and calculated saturation temperature of water + HCl + ethanol system using two rigorous electrolyte models. - Highlights: • Data for the water + HCl + ethanol VLE is reported at 78 kPa. • The VLE for the system water + HCl + ethanol was determined. • A new set of parameters for extended UNIQUAC model were correlated. • A new set of parameters for LIQUAC model were correlated. - Abstract: In this work, the isobaric vapor-liquid equilibrium (VLE) data obtained for the ternary system water + HCl + ethanol at 78 kPa, using an Ellis still, were studied. Two rigorous electrolyte models (extended UNIQUAC and LIQUAC) were fitted to the experimental data. Ethanol-H + , water-H + , ethanol-Cl − , water-Cl − , and Cl − -H + interaction parameters were determined. Likewise, Henry’s law constants for the volatile electrolyte were defined. A high goodness of fit was obtained for both electrolyte models; however, the extended UNIQUAC one showed better performance (AAD = 0.1326%). Two azeotropes observed in the system were accurately predicted (ethanol + water: x EtOH = 0.86 at 344.6 K; and HCl + water: x HCl = 0.11 at 375.5 K).

  19. Ionization and solvation of HCl adsorbed on the D2O-ice surface

    International Nuclear Information System (INIS)

    Kondo, M.; Kawanowa, H.; Gotoh, Y.; Souda, R.

    2004-01-01

    The interaction of HCl with the D 2 O-ice surface has been investigated in the temperature range 15-200 K by utilizing time-of-flight secondary ion mass spectroscopy, temperature-programmed desorption, and x-ray photoelectron spectroscopy. The intensities of sputtered H + (D 2 O) and Cl - ions (the H + ions) are increased (decreased) markedly above 40 K due to the hydrogen bond formation between the HCl and D 2 O molecules. The HCl molecules which form ionic hydrates undergo H/D exchange at 110-140 K and a considerable fraction of them dissolves into the bulk above 140 K. The neutral hydrates of HCl should coexist as evidenced by the desorption of HCl above 170 K. They are incorporated completely in the D 2 O layer up to 140 K. The HCl molecules embedded in the thick D 2 O layer dissolve into the bulk, and the ionic hydrate tends to segregate to the surface above 150 K

  20. 40 CFR 796.1050 - Absorption in aqueous solution: Ultraviolet/visible spectra.

    Science.gov (United States)

    2010-07-01

    ... applied to measure the absorption spectra. (b) Method—(1)(i) Introduction, purpose, scope, relevance... volume of HCl or NaOH in aqueous solution ([HCl], [NaOH]=1 mol/L). (4) In theory, all chemical species...) Katelaar, J.A.A., Photoelectric Spectrometry Group Bulletin, 8, (Cambridge, 1955). (3) Chemical Rubber...

  1. Development and application of a quasi-continuously working system for measuring the immission of acid air pollutants like HCl, NO2 and SO2 using an absorber tube

    International Nuclear Information System (INIS)

    Weisweiler, W.; Creutznacher, H.; Wien, F.

    1993-10-01

    Main objective of this study during the report time is found to be the testing of different absorption materials for the simultaneous determination of acid gaseous pollutants like HCl, NO 2 and SO 2 . These materials - so-called active collectors - were examined in laboratory-scale experiments using gas mixtures with various concentrations of the pollutants which should be chemisorbed by the active collectors. After eluation of the active collector and ion chromatographical analysis of the solutions informations about the absorption/desorption rate are obtained. In most cases adsorption were tested on which amino-functional groups are deposited by chemical reaction. The amino-groups act as reactive sites for the chemisorption of the acid gases. It can be observed that all tested materials are suitable for the measurement of HCl and SO 2 . Additionally some types of absorption materials are effective for the simultaneous absorption of HCl, SO 2 and NO 2 . (orig.). 25 figs., 21 tabs., 66 refs

  2. Study of a novel agent for TCA precipitated proteins washing - comprehensive insights into the role of ethanol/HCl on molten globule state by multi-spectroscopic analyses.

    Science.gov (United States)

    Eddhif, Balkis; Lange, Justin; Guignard, Nadia; Batonneau, Yann; Clarhaut, Jonathan; Papot, Sébastien; Geffroy-Rodier, Claude; Poinot, Pauline

    2018-02-20

    -precipitated proteins, with the aim to produce high-quality protein extracts which can be directly analyzed by LC-MS. An opening study on standard solutions showed that ethanol/HCl led to reduced losses of proteins compared to usual solvents (i.e. acetone and ethanol). This reagent also enabled a better solubilization of proteins in aqueous buffer that is necessary for their direct trypsin digestion and LC-HRMS analysis. A mechanistic study, performed through several spectroscopic analyses (LC-HRMS, Raman, spectrofluorometry), showed that treatment with ethanol/HCl induced conformational changes of TCA-precipitated proteins. Finally, we compared the efficiency of ethanol/HCl to published protocols for the washing of protein extracts from three different complex samples (i.e. soil, biofilm, and mouse liver). Our results demonstrated that ethanol/HCl is a valuable alternative to previous protein washing methods and, therefore could become a useful tool in mass spectrometry-based proteomics workflows for various applications (e.g. clinical research, chemical biology, environmental metaproteomics…). Copyright © 2017 Elsevier B.V. All rights reserved.

  3. The Marine Guanidine Alkaloid Crambescidin 816 Induces Calcium Influx and Cytotoxicity in Primary Cultures of Cortical Neurons through Glutamate Receptors.

    Science.gov (United States)

    Mendez, Aida G; Juncal, Andrea Boente; Silva, Siguara B L; Thomas, Olivier P; Martín Vázquez, Víctor; Alfonso, Amparo; Vieytes, Mercedes R; Vale, Carmen; Botana, Luís M

    2017-07-19

    Crambescidin 816 is a guanidine alkaloid produced by the sponge Crambe crambe with known antitumoral activity. While the information describing the effects of this alkaloid in central neurons is scarce, Cramb816 is known to block voltage dependent calcium channels being selective for L-type channels. Moreover, Cramb816 reduced neuronal viability through an unknown mechanism. Here, we aimed to describe the toxic activity of Cramb816 in cortical neurons. Since calcium influx is considered the main mechanism responsible for neuronal cell death, the effects of Cramb816 in the cytosolic calcium concentration of cortical neurons were studied. The alkaloid decreased neuronal viability and induced a dose-dependent increase in cytosolic calcium that was also related to the presence of calcium in the extracellular media. The increase in calcium influx was age dependent, being higher in younger neurons. Moreover, this effect was prevented by glutamate receptor antagonists, which did not fully block the cytotoxic effect of Cramb816 after 24 h of treatment but completely prevented Cramb816 cytotoxicity after 10 min exposure. Therefore, the findings presented herein provide new insights into the cytotoxic effect of Cramb816 in cortical neurons.

  4. The Isolation of Nanofibre Cellulose from Oil Palm Empty Fruit Bunch Via Steam Explosion and Hydrolysis with HCl 10%

    Science.gov (United States)

    Gea, S.; Zulfahmi, Z.; Yunus, D.; Andriayani, A.; Hutapea, Y. A.

    2018-03-01

    Cellulose nanofibrils were obtained from oil palm empty fruit bunch using steam explosion and hydrolized with 10% solution of HCl. Steam explosion coupled with acid hydrolysis pretreatment on the oil palm empty fruit bunch was very effective in the depolymerization and defibrillation process of the fibre to produce fibers in nanodimension. Structural analysis of steam exploded fibers was determined by Fourier Transform Infrared (FT-IR) spectroscopy. Thermal stability of cellulose measured using image analysis software image J. Characterization of the fibers by TEM and SEM displayed that fiber diameter decreases with mechanical-chemical treatment and final nanofibril size was 20-30 nm. FT-IR and TGA data confirmed the removal of hemicellulose and lignin during the chemical treatment process.

  5. The inhibition performance of long-chain alkyl-substituted benzimidazole derivatives for corrosion of mild steel in HCl

    International Nuclear Information System (INIS)

    Zhang, Dongqin; Tang, Yongming; Qi, Sijun; Dong, Dawei; Cang, Hui; Lu, Gang

    2016-01-01

    Highlights: • Inhibition performance of long-chain alkyl-substituted benzimidazole. • Benzimidazole segment donating electrons to metal surface. • Non-polar long chain enhancing inhibition by the barrier effect. • Molecular form of DBI more tightly adsorbs on the steel than its protonated form. - Abstract: The corrosion inhibition of a new benzimidazole derivative, 6-(dodecyloxy)-1H-benzo[d]imidazole (DBI), for mild steel in 1 M HCl was investigated in this paper. Computational chemistry was performed to explore the adsorption of DBI on metal surface. Inhibition performance of DBI is attributed to both the direct interaction of benzimidazole segment with iron surface and the barrier effect of the non-polar long chain against aggressive solution. Compared to the protonated form, the molecular form of DBI could more tightly interact with iron surface. These results show that the long-chain alkyl-substituted benzimidazole derivative is of great potential application as corrosion inhibitor.

  6. Effect of HCl pre-treatment on corrosion resistance of cerium-based conversion coatings on magnesium and magnesium alloys

    International Nuclear Information System (INIS)

    Brunelli, Katya; Dabala, Manuele; Calliari, Irene; Magrini, Maurizio

    2005-01-01

    The corrosion protection afforded by a cerium conversion coating, formed by immersion in a solution containing rare earth salt and hydrogen peroxide, on pure magnesium and two magnesium alloys, AZ91 and AM50, has been studied. The effect of HCl pre-treatments on the morphology and on the corrosion resistance of the cerium conversion layer was investigated. A thicker and more homogeneous distribution of the conversion coating was obtained when the sample surface was pre-treated with acid. Higher amounts of cerium on the surface of the pre-treated samples were detected. The cerium conversion coating increased the corrosion resistance of the alloys because it ennobled the corrosion potential and decreased both the anodic and cathodic current. The acid pre-treatment further increased the corrosion resistance of the coated alloys. After five days of immersion in chloride environment the untreated samples showed localized corrosion while the chemical conversion coated samples appeared unaffected

  7. Vibrational relaxation and energy transfer of matrix isolated HCl and DCl

    Energy Technology Data Exchange (ETDEWEB)

    Wiesenfeld, J.M.

    1977-12-01

    Vibrational kinetic and spectroscopic studies have been performed on matrix-isolated HCl and DCl between 9 and 20 K. Vibrational relaxation rates for v = 2 and v = 1 were measured by a tunable infrared laser-induced, time-resolved fluorescence technique. In an Ar matrix, vibrational decay times are faster than radiative and it is found that HCl relaxes about 35 times more rapidly than CCl, in spite of the fact that HCl must transfer more energy to the lattice than DCl. This result is explained by postulating that the rate-determining step for vibrational relaxation produces a highly rotationally excited guest in a V yield R step; rotational relaxation into lattice phonons follows rapidly. HCl v = 1, but not v = 2, excitation rapidly diffuses through the sample by a resonant dipole-dipole vibrational energy transfer process. Molecular complexes, and in particular the HCl dimer, relax too rapidly for direct observation, less than or approximately 1 ..mu..s, and act as energy sinks in the energy diffusion process. The temperature dependence for all these processes is weak--less than a factor of two between 9 and 20 K. Vibrational relaxation of HCl in N/sub 2/ and O/sub 2/ matrices is unobservable, presumably due to rapid V yield V transfer to the host. A V yield R binary collision model for relaxation in solids is successful in explaining the HCl(DCl)/Ar results as well as results of other experimenters. The model considers relaxation to be the result of ''collisions'' due to molecular motion in quantized lattice normal modes--gas phase potential parameters can fit the matrix kinetic data.

  8. Vibrational relaxation and energy transfer of matrix isolated HCl and DCl

    International Nuclear Information System (INIS)

    Wiesenfeld, J.M.

    1977-12-01

    Vibrational kinetic and spectroscopic studies have been performed on matrix-isolated HCl and DCl between 9 and 20 K. Vibrational relaxation rates for v = 2 and v = 1 were measured by a tunable infrared laser-induced, time-resolved fluorescence technique. In an Ar matrix, vibrational decay times are faster than radiative and it is found that HCl relaxes about 35 times more rapidly than CCl, in spite of the fact that HCl must transfer more energy to the lattice than DCl. This result is explained by postulating that the rate-determining step for vibrational relaxation produces a highly rotationally excited guest in a V yield R step; rotational relaxation into lattice phonons follows rapidly. HCl v = 1, but not v = 2, excitation rapidly diffuses through the sample by a resonant dipole-dipole vibrational energy transfer process. Molecular complexes, and in particular the HCl dimer, relax too rapidly for direct observation, less than or approximately 1 μs, and act as energy sinks in the energy diffusion process. The temperature dependence for all these processes is weak--less than a factor of two between 9 and 20 K. Vibrational relaxation of HCl in N 2 and O 2 matrices is unobservable, presumably due to rapid V yield V transfer to the host. A V yield R binary collision model for relaxation in solids is successful in explaining the HCl(DCl)/Ar results as well as results of other experimenters. The model considers relaxation to be the result of ''collisions'' due to molecular motion in quantized lattice normal modes--gas phase potential parameters can fit the matrix kinetic data

  9. Densities and apparent molar volumes of HClO{sub 4}(aq) and Yb(ClO{sub 4}){sub 3}(aq) at elevated temperatures and pressures

    Energy Technology Data Exchange (ETDEWEB)

    Hakin, Andrew W. E-mail: hakin@uleth.ca; Lukacs, Michael J.; Jin Lianliu

    2004-09-01

    Relative densities have been measured for acidified aqueous solutions of ytterbium perchlorate {l_brace}Yb(ClO{sub 4}){sub 3}{r_brace} at approximately T=(348.15, 373.15, 398.15, and 423.15) K and p=(10.0, 20.0, and 30.0) MPa over the concentration range 0.01624{<=}m{sub 2}/(mol {center_dot} kg{sup -1}) {<=} 0.2531 using an optically coupled vibrating tube densimeter (OCVTD). Experimental apparent molar volumes have been calculated from the density measurements, and apparent molar volumes for the aqueous perchlorate salt have been calculated using Young's rule. The application of Young's rule requires apparent molar volumes for aqueous perchloric acid (HClO{sub 4}) solutions over extended temperature and pressure ranges. These values were calculated from densities for aqueous HClO{sub 4} solutions that were measured using the OCVTD at the same temperatures and pressures as those used to investigate the density surface of the acidified aqueous Yb(ClO{sub 4}){sub 3} solutions. The temperature, pressure, and composition surfaces of the apparent molar volumes for Yb(ClO{sub 4}){sub 3}(aq) and HClO{sub 4}(aq) have been modelled using Pitzer ion-interaction equations. Apparent molar volumes at infinite dilution obtained from these models have been compared to those which can be calculated using the semi-empirical Helgeson, Kirkham, and Flowers equations of state. Values for the apparent molar volume at infinite dilution of the ytterbium trivalent cation have also been calculated using simple additivity principles.

  10. Electroerosion method for preparation of saturated solutions of ruthenium hydroxochloride

    International Nuclear Information System (INIS)

    Mikhalev, V.A.; Andrianov, G.A.; Zhadanov, B.V.; Ryazanov, A.I.

    1987-01-01

    A pilot plant for carrying out electroerosion processes using pulse current of high unit power is developed. The solution process of metallic Ru in concentrated HCl is investigated. The possibility of preparation of ruthenium hydroxochloride solutions of 300 g/l concentration is established; it gives the possibility of Ru solution under conditions similar to the process of salting out

  11. Effects of Topical Phenylephrine HCl 2.5% used before Cataract Surgery on Systemic Blood Pressure

    Directory of Open Access Journals (Sweden)

    Emre Ayıntap

    2011-06-01

    Full Text Available Purpose: To evaluate the effect of topical phenylephrine HCl 2.5% (Mydfrin, used as a fast and effective mydriatic before cataract surgery, on systemic blood pressure. Material and Method: Topical phenylephrine HCl 2.5% was administered 3 times with 5-minute intervals before cataract surgery to 44 eyes of 44 patients. The systemic blood pressure was measured preoperatively and at 15 and 30 minutes. Results: The mean systolic blood pressure before the topical administration of phenylephrine HCl 2.5% was 119.7mmHg, while 15 and 30 minutes later, it was 125.3 mmHg and 121.2 mmHg, respectively. The mean diastolic blood pressure before the topical administration of phenylephrine HCl 2.5% was 75.9 mmHg; 15 and 30 minutes later, it was 76.9 mmHg and 75.3 mmHg, respectively. The increase in systolic blood pressure at 15 and 30 minutes was statistically significant (p=0.003 and p=0.042. The change in diastolic blood pressure was not statistically significant. Discussion: Phenylephrine HCl 2.5%, which is used preoperatively as a fast and effective mydriatic for cataract surgery, can increase the systolic blood pressure. This effect is most significant at 15 minutes and lasts at least 30 minutes. This agent should be used with care in hypertensive patients. (Turk J Ophthalmol 2011; 41: 164-6

  12. Penentuan Nilai Kalor Serta Pengaruh Asam Klorida (Hcl Terhadap Kadar Bioetanol Bonggol Pisang (Musa Paradisiacal

    Directory of Open Access Journals (Sweden)

    Asri Saleh

    2016-01-01

    Full Text Available The research of influence bioetanol degree to chlorine acid catalyst concentration (HCl in the hydrolysis process banana’s bump (Musa paradisiacal has the goal to know the influence of catalyst concentration variation HCl was given the result of banana’s bump hydrolysis which maximum on catalyst variation HCl 0,5 M; 1,0 M; 1,5 M; 2,0 M and 2,5 M on temperature 70oC, 150 rpm during 120 minute with appointment of calor percentage on optimum etanol degree. Based on the result of the research etanol degree highest on HCl with concentration 2,5 with bioetanol degree 5.29% per 10 gram banana’s bump. Based on the ANAVA calculation found out F calculate < F table so that H0 accepted and H1 refused. It’s mean that there were not influenced of concentration HCl to bioetanol degree significantly. Percentage of bioetanol calor which found out on concentration HC1 2,5 M (maximum concentration were 3461 (Sample I  and 3384 kkal (Sample II.

  13. Production and infectivity of inoculum of arbuscular mycorrhizal fungi multiplied in a substrate supplemented with Tris-HCl buffer Produção e infectividade de inóculo de fungos micorrízicos arbusculares multiplicados em substrato suplementado com tampão Tris-HCl

    Directory of Open Access Journals (Sweden)

    Fábio Sérgio Barbosa da Silva

    2007-12-01

    Full Text Available The effect of adding Tris-HCl buffer on production and infectivity of AMF inoculum was investigated. Sporulation of Glomus etunicatum, Acaulospora longula and Gigaspora albida was improved in solution with buffer. The infectivity of G. etunicatum increased after storage, what suggests that the inoculum of this isolate is benefited by storage.O efeito da adição do tampão Tris-HCl na produção e infectividade de inóculo foi investigado. A esporulação de Glomus etunicatum, Acaulospora longula e Gigaspora albida foi incrementada utilizando solução com tampão. A infectividade de G. etunicatum aumentou após estocagem, sugerindo que o inóculo deste isolado é beneficiado pelo armazenamento.

  14. A shrinking particle model at leaching of titanium in ilmenite use HCl

    International Nuclear Information System (INIS)

    MV Purwani; Suyanti

    2016-01-01

    The research of ilmenite leaching has conducted. Ilmenite was tailings of zircon sand processing. Zircon sand processing tailings containing Zr, Ti, Nb and Fe. This research will be conducted to determine the kinetic leaching of Ti in HCl based shrinking core models. From the research results ilmenite leaching of Ti in HCl wear, it can be concluded that the 50 grams of ilmenite leaching wear 11 M HCl leaching, the higher temperature was conducted the greater of the Ti conversion. The mechanism of the leaching process was controlled by Sphere Reaction with formula equation 1- (1-α)1/3 = "k"."C"/"r"_o"ρ t = klt, the relationship between temperature (T) with the reaction rate constant (k), k = 61.744.e- 4553.3 / T or ln k = - 4553.3 / T + 4.123, the frequency factor A = 61.744, the activation energy E = 37.856 kJ/mol. (author)

  15. Beneficiation of titanium concentrate (anatase) by HCl/H2O2 leaching of impurities

    International Nuclear Information System (INIS)

    Trindade, R.B.E.; Teixeira, L.A.C.

    1988-01-01

    The HCl/H 2 O 2 leaching of impurities from a Brazilian anatase (TiO 2 ) concentrate has been investigated by factorial experimentations. The effects of the following variables were investigated: temperature (50-90 0 C), redox potential (with and without oxidizing agent-H 2 O 2 ) and HCl concentration (4-18,5%). The conclusions were based on the analyses of Fe, Ca, P, Al, Si, Th,Ce, La, U and Ti in the beneficiated concentrates. The final results recommended the following optimum operational conditions, in a four stage countercurrent leaching: in the 4 th reactor (discharge of beneficiated concentrate): HCl fed at 18.5%, T=75 0 C, and addition of H 2 O 2 at a potential (eH) of 850 mV; in the first three reactors: T=90 0 C; with no oxidizing agent. (author) [pt

  16. Subtype-specific Modulation of Acid-sensing Ion Channel (ASIC) Function by 2-Guanidine-4-methylquinazoline*

    Science.gov (United States)

    Alijevic, Omar; Kellenberger, Stephan

    2012-01-01

    Acid-sensing ion channels (ASICs) are neuronal Na+-selective channels that are transiently activated by extracellular acidification. ASICs are involved in fear and anxiety, learning, neurodegeneration after ischemic stroke, and pain sensation. The small molecule 2-guanidine-4-methylquinazoline (GMQ) was recently shown to open ASIC3 at physiological pH. We have investigated the mechanisms underlying this effect and the possibility that GMQ may alter the function of other ASICs besides ASIC3. GMQ shifts the pH dependence of activation to more acidic pH in ASIC1a and ASIC1b, whereas in ASIC3 this shift goes in the opposite direction and is accompanied by a decrease in its steepness. GMQ also induces an acidic shift of the pH dependence of inactivation of ASIC1a, -1b, -2a, and -3. As a consequence, the activation and inactivation curves of ASIC3 but not other ASICs overlap in the presence of GMQ at pH 7.4, thereby creating a window current. At concentrations >1 mm, GMQ decreases maximal peak currents by reducing the unitary current amplitude. Mutation of residue Glu-79 in the palm domain of ASIC3, previously shown to be critical for channel opening by GMQ, disrupted the GMQ effects on inactivation but not activation. This suggests that this residue is involved in the consequences of GMQ binding rather than in the binding interaction itself. This study describes the mechanisms underlying the effects of a novel class of ligands that modulate the function of all ASICs as well as activate ASIC3 at physiological pH. PMID:22948146

  17. Subtype-specific modulation of acid-sensing ion channel (ASIC) function by 2-guanidine-4-methylquinazoline.

    Science.gov (United States)

    Alijevic, Omar; Kellenberger, Stephan

    2012-10-19

    Acid-sensing ion channels (ASICs) are neuronal Na(+)-selective channels that are transiently activated by extracellular acidification. ASICs are involved in fear and anxiety, learning, neurodegeneration after ischemic stroke, and pain sensation. The small molecule 2-guanidine-4-methylquinazoline (GMQ) was recently shown to open ASIC3 at physiological pH. We have investigated the mechanisms underlying this effect and the possibility that GMQ may alter the function of other ASICs besides ASIC3. GMQ shifts the pH dependence of activation to more acidic pH in ASIC1a and ASIC1b, whereas in ASIC3 this shift goes in the opposite direction and is accompanied by a decrease in its steepness. GMQ also induces an acidic shift of the pH dependence of inactivation of ASIC1a, -1b, -2a, and -3. As a consequence, the activation and inactivation curves of ASIC3 but not other ASICs overlap in the presence of GMQ at pH 7.4, thereby creating a window current. At concentrations >1 mM, GMQ decreases maximal peak currents by reducing the unitary current amplitude. Mutation of residue Glu-79 in the palm domain of ASIC3, previously shown to be critical for channel opening by GMQ, disrupted the GMQ effects on inactivation but not activation. This suggests that this residue is involved in the consequences of GMQ binding rather than in the binding interaction itself. This study describes the mechanisms underlying the effects of a novel class of ligands that modulate the function of all ASICs as well as activate ASIC3 at physiological pH.

  18. Fluorescent determination of poly(hexamethylene guanidine) via the aggregates it forms with quantum dots and magnetic nanoparticles

    International Nuclear Information System (INIS)

    Likhachev, Konstantin V.; Beklemishev, Mikhail K.; Ovcharenko, Elena O.; Dityuk, Alexander I.; Efimov, Konstantin M.; Abramchuk, Sergei S.

    2016-01-01

    The authors report that the cationic polymer-oligomer poly(hexamethylene guanidine) (PHMG) in the form of its hydrochloride induces the formation of mixed aggregates composed of anionic magnetic nanoparticles (magNPs), PHMG and anionic quantum dots (QDs). The magNPs consisted of polymer-coated magnetite nanoparticles, and the QDs consisted of polymer-coated CdSe-CdS/ZnS nanoparticles with an emission maximum at 617 nm. This finding is exploited in a semi-quantitative method for the determination of PHMG. The protocol includes magnetic separation of the mixed aggregates (magNPs/PHMG/QDs) from the sample and excess QDs, redispersion of the aggregates in water, and measurement of fluorescence intensity. The signal is proportional to the concentration of PHMG in the 0.05 to 0.2 mg L"−"1 concentration range, with intra-day RSDs of up to 27 %. The limit of detection (LOD) of PHMG in spiked run-off waters, swimming pool water and wastewater is 23 μg L"−"1. This PHMG assay is selective in that high concentrations of surfactants and inorganic salts are tolerated. Polyethyleneimine and poly(diallyldimethylammonium chloride) also cause the formation of mixed aggregates but only at higher concentrations. Both a fluorometer and a digital camera (using a 365-nm LED as a light source) were used to measure fluorescence. In case of using a digital camera, the LOD is 40 μg L"−"1 and the intraday RSDs are up to 23 %. The method is sensitive, fairly selective and rather simple. (author)

  19. MicroRNA regulatory networks reflective of polyhexamethylene guanidine phosphate-induced fibrosis in A549 human alveolar adenocarcinoma cells.

    Science.gov (United States)

    Shin, Da Young; Jeong, Mi Ho; Bang, In Jae; Kim, Ha Ryong; Chung, Kyu Hyuck

    2018-05-01

    Polyhexamethylene guanidine phosphate (PHMG-phosphate), an active component of humidifier disinfectant, is suspected to be a major cause of pulmonary fibrosis. Fibrosis, induced by recurrent epithelial damage, is significantly affected by epigenetic regulation, including microRNAs (miRNAs). The aim of this study was to investigate the fibrogenic mechanisms of PHMG-phosphate through the profiling of miRNAs and their target genes. A549 cells were treated with 0.75 μg/mL PHMG-phosphate for 24 and 48 h and miRNA microarray expression analysis was conducted. The putative mRNA targets of the miRNAs were identified and subjected to Gene Ontology analysis. After exposure to PHMG-phosphate for 24 and 48 h, 46 and 33 miRNAs, respectively, showed a significant change in expression over 1.5-fold compared with the control. The integrated analysis of miRNA and mRNA microarray results revealed the putative targets that were prominently enriched were associated with the epithelial-mesenchymal transition (EMT), cell cycle changes, and apoptosis. The dose-dependent induction of EMT by PHMG-phosphate exposure was confirmed by western blot. We identified 13 putative EMT-related targets that may play a role in PHMG-phosphate-induced fibrosis according to the Comparative Toxicogenomic Database. Our findings contribute to the comprehension of the fibrogenic mechanism of PHMG-phosphate and will aid further study on PHMG-phosphate-induced toxicity. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Supplementation with rumen-protected L-arginine-HCl increased fertility in sheep with synchronized estrus.

    Science.gov (United States)

    de Chávez, Julio Agustín Ruiz; Guzmán, Adrian; Zamora-Gutiérrez, Diana; Mendoza, Germán David; Melgoza, Luz María; Montes, Sergio; Rosales-Torres, Ana María

    2015-08-01

    The aim of the present study was to evaluate the effects of L-arginine-HCl supplementation on ovulation rate, fertility, prolificacy, and serum VEGF concentrations in ewes with synchronized oestrus. Thirty Suffolk ewes with a mean body weight of 45 ± 3 kg and a mean body condition score (BCS) of 2.4 ± 0.28 were synchronized for estrus presentation with a progestin-containing sponge (20 mg Chronogest® CR) for 9 days plus PGF2-α (Lutalyse; Pfizer, USA) on day 7 after the insertion of the sponge. The ewes were divided into two groups; i.e., a control group (n = 15) that was fed on the native pasture (basal diet) and an L-arginine-HCl group (n = 15) that received 7.8 g of rumen-protected L-arginine-HCl from day 5 of the sponge insertion until day 25 after mating plus the basal diet. The L-arginine-HCl was administered daily via an esophageal probe between days 5 and 9 of the synchronization protocol and every third day subsequently. Blood samples were drawn from the jugular vein every 6 days throughout the entire experimental period. The results revealed that the L-arginine-HCl supplementation increased fertility during the synchronized estrus (P = 0.05). However, no effects were observed on the final BCS (P = 0.78), estrus presentation (P = 0.33), multiple ovulations (P = 0.24), prolificacy (P = 0.63), or serum VEGF concentration. In conclusion, L-arginine-HCl supplementation during the period used in this study increased fertility in sheep with synchronized estrus possibly due to improved embryo-fetal survival during early pregnancy.

  1. The maintenance of elevated active chlorine levels in the Antarctic lower stratosphere through HCl null cycles

    Science.gov (United States)

    Müller, Rolf; Grooß, Jens-Uwe; Mannan Zafar, Abdul; Robrecht, Sabine; Lehmann, Ralph

    2018-03-01

    The Antarctic ozone hole arises from ozone destruction driven by elevated levels of ozone destroying (active) chlorine in Antarctic spring. These elevated levels of active chlorine have to be formed first and then maintained throughout the period of ozone destruction. It is a matter of debate how this maintenance of active chlorine is brought about in Antarctic spring, when the rate of formation of HCl (considered to be the main chlorine deactivation mechanism in Antarctica) is extremely high. Here we show that in the heart of the ozone hole (16-18 km or 85-55 hPa, in the core of the vortex), high levels of active chlorine are maintained by effective chemical cycles (referred to as HCl null cycles hereafter). In these cycles, the formation of HCl is balanced by immediate reactivation, i.e. by immediate reformation of active chlorine. Under these conditions, polar stratospheric clouds sequester HNO3 and thereby cause NO2 concentrations to be low. These HCl null cycles allow active chlorine levels to be maintained in the Antarctic lower stratosphere and thus rapid ozone destruction to occur. For the observed almost complete activation of stratospheric chlorine in the lower stratosphere, the heterogeneous reaction HCl + HOCl is essential; the production of HOCl occurs via HO2 + ClO, with the HO2 resulting from CH2O photolysis. These results are important for assessing the impact of changes of the future stratospheric composition on the recovery of the ozone hole. Our simulations indicate that, in the lower stratosphere, future increased methane concentrations will not lead to enhanced chlorine deactivation (through the reaction CH4 + Cl → HCl + CH3) and that extreme ozone destruction to levels below ≈ 0.1 ppm will occur until mid-century.

  2. HERSCHEL/HIFI DISCOVERY OF HCL{sup +} IN THE INTERSTELLAR MEDIUM

    Energy Technology Data Exchange (ETDEWEB)

    De Luca, M.; Gerin, M.; Falgarone, E. [LERMA-LRA, UMR 8112 du CNRS, Observatoire de Paris, Ecole Normale Superieure, UPMC and UCP, 24 rue Lhomond, 75231 Paris Cedex 05 (France); Gupta, H.; Drouin, B. J.; Pearson, J. C. [Jet Propulsion Laboratory, Caltech, Pasadena, CA 91109 (United States); Neufeld, D. [Department of Physics and Astronomy, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Teyssier, D. [European Space Astronomy Centre, ESA, P.O. Box 78, E-28691 Villanueva de la Canada, Madrid (Spain); Lis, D. C.; Monje, R.; Phillips, T. G. [California Institute of Technology, Cahill Center for Astronomy and Astrophysics 301-17, Pasadena, CA 91125 (United States); Goicoechea, J. R.; Godard, B.; Bell, T. A. [Centro de Astrobiologia (CSIC/INTA), Ctra. de Torrejon a Ajalvir, km 4, 28850 Torrejon de Ardoz, Madrid (Spain); Coutens, A. [Universite de Toulouse, UPS-OMP, IRAP, Toulouse (France)

    2012-06-01

    The radical ion HCl{sup +}, a key intermediate in the chlorine chemistry of the interstellar gas, has been identified for the first time in the interstellar medium with the Herschel Space Observatory's Heterodyne Instrument for the Far-Infrared. The ground-state rotational transition of H{sup 35}Cl{sup +}, {sup 2}{Pi}{sub 3/2} J = 5/2-3/2, showing {Lambda}-doubling and hyperfine structure, is detected in absorption toward the Galactic star-forming regions W31C (G10.6-0.4) and W49N. The complex interstellar absorption features are modeled by convolving in velocity space the opacity profiles of other molecular tracers toward the same sources with the fine and hyperfine structure of HCl{sup +}. This structure is derived from a combined analysis of optical data from the literature and new laboratory measurements of pure rotational transitions, reported in the accompanying Letter by Gupta et al. The models reproduce well the interstellar absorption, and the frequencies inferred from the astronomical observations are in exact agreement with those calculated using spectroscopic constants derived from the laboratory data. The detection of H{sup 37}Cl{sup +} toward W31C, with a column density consistent with the expected {sup 35}Cl/{sup 37}Cl isotopic ratio, provides additional evidence for the identification. A comparison with the chemically related molecules HCl and H{sub 2}Cl{sup +} yields an abundance ratio of unity with both species (HCl{sup +} : H{sub 2}Cl{sup +} : HCl {approx} 1). These observations also yield the unexpected result that HCl{sup +} accounts for 3%-5% of the gas-phase chlorine toward W49N and W31C, values several times larger than the maximum fraction ({approx}1%) predicted by chemical models.

  3. Utilization of a Green Brominating Agent for the Spectrophotometric Determination of Pipazethate HCl in Pure Form and Pharmaceutical Preparations

    Directory of Open Access Journals (Sweden)

    Ayman A. Gouda

    2013-01-01

    Full Text Available Five simple, accurate, and sensitive spectrophotometric methods (A–E have been described for the indirect assay of pipazethate HCl (PZT either in pure form or in pharmaceutical preparations. The proposed methods are based on the bromination of pipazethate HCl with a solution of excess bromate-bromide mixture in hydrochloric acid medium and subsequent estimation of the residual bromine by different reaction schemes. In the first three methods (A–C, the determination of the residual bromine is based on its ability to bleach the color of methyl orange, indigo carmine, or thymol blue dyes and measuring the absorbance at 520, 610, and 550 nm for methods A, B, and C, respectively. Methods D and E involves treating the unreacted bromine with a measured excess of iron(II, and the remaining iron(II is complexed with 1,10-phenanthroline, and the increase in absorbance is measured at 510 nm for method D and the resulting iron(III is complexed with thiocyanate and the absorbance is measured at 480 nm for method E. The different experimental parameters affecting the development and stability of the color are carefully studied and optimized. Regression analysis of the Beer-Lambert plots showed good correlation in the concentration ranges of 0.5–8.0 μg . The apparent molar absorptivity, Sandell's sensitivity, detection and quantitation limits were evaluated. The proposed methods have been applied and validated successfully for the analysis of the drug in its pure form and pharmaceutical formulations with mean recoveries of 99.94%–100.15% and relative standard deviation ≤1.53. No interference was observed from a common pharmaceutical adjuvant. Statistical comparison of the results with the reference method shows excellent agreement and indicates no significant difference in accuracy and precision.

  4. Readily Available Chiral Benzimidazoles-Derived Guanidines as Organocatalysts in the Asymmetric α-Amination of 1,3-Dicarbonyl Compounds.

    Science.gov (United States)

    Benavent, Llorenç; Puccetti, Francesco; Baeza, Alejandro; Gómez-Martínez, Melania

    2017-08-11

    The synthesis and the evaluation as organocatalysts of new chiral guanidines derived from benzimidazoles in the enantioselective α-amination of 1,3-dicarbonyl compounds using di- t -butylazodicarboxylate as aminating agent is herein disclosed. The catalysts are readily synthesized through the reaction of 2-chlorobezimidazole and a chiral amine in moderate-to-good yields. Among all of them, those derived from ( R )-1-phenylethan-1-amine ( 1 ) and ( S )-1-(2-naphthyl)ethan-1-amine ( 3 ) turned out to be the most efficient for such asymmetric transformation, rendering good-to-high yields and moderate-to-good enantioselectivities for the amination products.

  5. Thermodynamic equilibrium model to predict the cobalt distribution coefficient in the CoCl2--HCl--H2O--TBP liquid--liquid extraction system

    International Nuclear Information System (INIS)

    Nevarez, M.; Bautista, R.G.

    1976-01-01

    The development of a thermodynamic equilibrium model to predict the cobalt distribution coefficient in the CoCl 2 -HCl-H 2 O-TBP system is described. The model makes use of the various aqueous phase cobaltous chloride complexes stoichiometric stability constants expressed as their degree of formation, their mechanism of extraction into the organic phase, and the equilibrium constant for the extraction reaction. The model was verified by the good agreement between the calculated cobalt distribution coefficients and those obtained experimentally both in the present study and published by other investigators. The optimum extraction of cobalt by the TBP occurred at an HCl equilibrium aqueous place concentration between 8.5 and 9.5M. The development of efficient procedures for the separation and concentration of important industrial metals from their aqueous solutions by liquid-liquid extraction has recently been given impetus by the realization of an impending shortage of energy and mineral resources. Liquid-liquid extraction is one of the few methods by which it is possible to quantitatively separate elements which are similar in properties. The use of liquid-liquid extraction to separate cobalt and nickel, which very frequently occur in nature together, is an important separation problem in nonferrous metallurgy. There is some fundamental information available in the chemical literature regarding the mechanism and equilibrium thermodynamic properties of selected liquid-liquid extraction systems. This research effort shows how this available information can be utilized to improve existing separation and concentration theory and technique. The development and application of a thermodynamic equilibrium model for describing the liquid-liquid extraction of cobaltous chloride from aqueous HCl solutions by tributyl phosphate (TBP) using experimental data obtained in this investigation and from the literature are presented

  6. Solution microcalorimeter for measuring heats of solution of radioactive elements and compounds

    International Nuclear Information System (INIS)

    Raschella, D.L.

    1978-12-01

    The microcalorimeter vessel is constructed of tantalum metal, with a nominal volume of 5 cm 3 . Its energy equivalent is 24 J K -1 when containing 5 cm 3 H 2 O. The thermal leakage modulus is 0.010 min -1 . A thermistor is employed as the temperature sensor. The operating sensitivity is about 1 x 10 -5 K (300 μJ). The performance of the calorimetry system was tested using tris(hydroxymethyl)aminomethane (TRIS) and magnesium metal. The results of the TRIS experiments, at a concentration of 1 g dm -3 in 0.1 N HCl at 298 K, yielded a heat of solution of -29.606 +- 0.063 kJ mol -1 . The magnesium experiments, in 1 N HCl at 298 K, gave a heat of solution of -465.965 +- 1.136 kJ mol -1 . The heat of solution of curium-248 metal in 1 N HCl at 298 K was measured. The experiments, which should not be considered definitive, yielded a heat of solution of -606.4 +- 1.8 kJ mol -1 . A single measurement in 6 N HCl gave a heat of solution of -602.3 kJ mol -1 . From these results the heat of formation of Cm 3+ /sub (aq)/ is calculated to be -607.2 +- 2.5 kJ mol -1

  7. Artocarpus heterophyllus L. seed starch-blended gellan gum mucoadhesive beads of metformin HCl.

    Science.gov (United States)

    Nayak, Amit Kumar; Pal, Dilipkumar; Santra, Kousik

    2014-04-01

    Jackfruit (Artocarpus heterophyllus Lam., family: Moraceae) seed starch (JFSS)-gellan gum (GG) mucoadhesive beads containing metformin HCl were developed through ionotropic gelation technique. The effect of GG to JFSS ratio and CaCl2 concentration on the drug encapsulation efficiency (DEE, %) and cumulative drug release at 10h (R10h, %) was optimized and analyzed using response surface methodology based on 3(2) factorial design. The optimized JFSS-GG beads containing metformin HCl showed DEE of 92.67±4.46%, R10h of 61.30±2.37%, and mean diameter of 1.67±0.27 mm. The optimized beads showed pH-dependent swelling and mucoadhesivity with the goat intestinal mucosa. The in vitro drug release from all these JFSS-GG beads containing metformin HCl was followed zero-order pattern (R(2)=0.9907-0.9975) with super case-II transport mechanism over a period of 10 h. The beads were also characterized by SEM and FTIR. The optimized JFSS-GG beads containing metformin HCl exhibited significant hypoglycemic effect in alloxan-induced diabetic rats over prolonged period after oral administration. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Analysis of a novel chlorine recycling process based on anhydrous HCl oxidation

    International Nuclear Information System (INIS)

    Martinez, Isai Gonzalez; Vidaković-Koch, Tanja; Kuwertz, Rafael; Kunz, Ulrich; Turek, Thomas; Sundmacher, Kai

    2014-01-01

    Graphical abstract: - Highlights: • Gas phase HCl electrolysis combined with oxygen reduction reaction (oxygen depolarized cathode) for chlorine production. • Determination of potential losses in half-cell measurements under technically relevant conditions. • Optimization of gas diffusion electrodes with respect to Nafion and catalyst loadings. • The optimal Nafion content in the catalyst layer for HCl oxidation is much higher than for other gas phase reactions, such as the oxygen reduction in the cathode. • Nafion improves catalyst dispersion, but catalyst utilization depends on the diffusion and absorption properties of the educts in the ionomer phase. - Abstract: A novel process for the recycling of chlorine based on the gaseous HCl oxidation on gas diffusion electrodes has been investigated. The cathodic and anodic reactions have been analyzed separately as half-cell reactions in a cyclone flow cell and optimized regarding catalyst as well as ionomer loadings. For the anodic hydrogen chloride oxidation, an optimal value of ca. 60 wt% Nafion has been found, whereas for the cathodic oxygen reduction a value below 37 wt% has been obtained. This discrepancy was mainly attributed to the different absorption and transport properties of HCl in Nafion compared to oxygen. The main potential losses in the reactor were identified at the cathode

  9. Benzydamine HCl, a new agent for the treatment of radiation mucositis of the oropharynx

    International Nuclear Information System (INIS)

    Kim, J.H.; Chu, F.C.; Lakshmi, V.; Houde, R.

    1986-01-01

    Benzydamine HCl is a new nonsteroidal analgesic and anti-inflammatory compound which is not chemically related to local anesthetics such as procaine and xylocaine. A double-blind, randomized clinical investigation was carried out to determine the analgesic and anti-inflammatory effectiveness of benzydamine HCl in patients with radiation-induced mucositis of the oropharynx. Of the 67 patients in the study, 37 were on benzydamine and 30 on placebo. Patients developed radiation mucositis, hyperemia, and throat pain when the total radiation dose reached above 2000 rad over 2 weeks (200 rad per fraction, five treatments per week). Analysis of the data showed that benzydamine HCl used as a rinse/gargle provided a statistically significant and clinically meaningful alleviation of the symptoms of oropharyngeal mucositis. There was also significant improvement in terms of reduction in hyperemia and mucositis in benzydamine group. No systemic side effects associated with benzydamine medication were noted. In view of the relative ineffectiveness of systemic analgesics and topical anesthetics for these conditions, benzydamine HCl promises to be a useful addition to the therapeutic armamentarium

  10. Inhibition of Corrosion of Zinc in (HNO 3 + HCl) acid mixture by ...

    African Journals Online (AJOL)

    Corrosion of Zinc metal in (HNO3 + HCl) binary acid mixture and inhibition efficiency of aniline has been studied by weight loss method and polarization technique. Corrosion rate increases with the concentration of acid mixture and the temperature. Inhibition efficiency (I.E.) of aniline increases with the concentration of ...

  11. HCl Flow-Induced Phase Change of α-, β-, and ε-Ga2O3 Films Grown by MOCVD

    KAUST Repository

    Sun, Haiding; Li, Kuang-Hui; Castanedo, C. G. Torres; Okur, Serdal; Tompa, Gary S.; Salagaj, Tom; Lopatin, Sergei; Genovese, Alessandro; Li, Xiaohang

    2018-01-01

    inducing the phase change by increasing the HCl flow in the reactor. Thus, it is plausible that the HCl acted as a catalyst during the phase transformation process. Furthermore, we revealed the microstructure and the epitaxial relationship between Ga2O3

  12. 40 CFR 63.7507 - What are the health-based compliance alternatives for the hydrogen chloride (HCl) and total...

    Science.gov (United States)

    2010-07-01

    ... alternatives for the hydrogen chloride (HCl) and total selected metals (TSM) standards? 63.7507 Section 63.7507... Standards for Hazardous Air Pollutants for Industrial, Commercial, and Institutional Boilers and Process... the hydrogen chloride (HCl) and total selected metals (TSM) standards? (a) As an alternative to the...

  13. Airway hyperresponsiveness induced by repeated esophageal infusion of HCl in guinea pigs.

    Science.gov (United States)

    Cheng, Yan-Mei; Cao, Ai-Li; Zheng, Jian-Pu; Wang, Hong-Wei; Sun, Yong-Shun; Liu, Chun-Fang; Zhang, Bei-Bei; Wang, Yi; Zhu, Sheng-Liang; Wu, Da-Zheng

    2014-11-01

    Gastroesophageal reflux is a common disorder closely related to chronic airway diseases, such as chronic cough, asthma, chronic bronchitis, and chronic obstructive disease. Indeed, gastroesophageal acid reflux into the respiratory tract causes bronchoconstriction, but the underlying mechanisms have still not been clarified. This study aimed to elucidate functional changes of bronchial smooth muscles (BSMs) isolated from guinea pigs in an animal model of gastroesophageal reflux. The marked airway inflammation, hyperresponsiveness and remodeling were observed after guinea pigs were exposed to intraesophageal HCl infusion for 14 days. In addition, contractile responses to acetylcholine (ACh), KCl, electrical field stimulation, and extracellular Ca(2+) were greater in guinea pigs infused with HCl compared with control groups. The L-type voltage-dependent Ca(2+) channels (L-VDCC) blocker, nicardipine, significantly inhibited ACh- and Ca(2+)-enhanced BSM contractions in guinea pigs infused with HCl. The Rho-kinase inhibitor, Y27632, attenuated ACh-enhanced BSM contractions in guinea pigs infused with HCl. Moreover, mRNA and protein expressions for muscarinic M2 and M3 receptors, RhoA, and L-VDCC in BSM were detected by real-time PCR and Western blot. Expressions of mRNA and protein for muscarinic M3 receptors, RhoA, and L-VDCC were greater than in BSM of HCl-infused guinea pigs, whereas levels of muscarinic M2 receptors were unchanged. We demonstrate that acid infusion to the lower esophagus and, subsequently, microaspiration into the respiratory tract in guinea pigs leads to airway hyperresponsiveness and overactive BSM. Functional and molecular results indicate that overactive BSM is the reason for enhancement of extracellular Ca(2+) influx via L-VDCC and Ca(2+) sensitization through Rho-kinase signaling.

  14. Local sustained delivery of bupivacaine HCl from a new castor oil-based nanoemulsion system.

    Science.gov (United States)

    Rachmawati, Heni; Arvin, Yang Aryani; Asyarie, Sukmadjaja; Anggadiredja, Kusnandar; Tjandrawinata, Raymond Rubianto; Storm, Gert

    2018-06-01

    Bupivacaine HCl (1-butyl-2',6'-pipecoloxylidide hydrochloride), an amide local anesthetic compound, is a local anesthetic drug utilized for intraoperative local anesthesia, post-operative analgesia and in the treatment of chronic pain. However, its utility is limited by the relative short duration of analgesia after local administration (approximately 9 h after direct injection) and risk for side effects. This work is aimed to develop a nanoemulsion of bupivacaine HCl with sustained local anesthetics release kinetics for improved pain management, by exhibiting extended analgesic action and providing reduced peak levels in the circulation to minimize side effects. Herein, biodegradable oils were evaluated for use in nanoemulsions to enable sustained release kinetics of bupivacaine HCl. Only with castor oil, a clear and stable nanoemulsion was obtained without the occurrence of phase separation over a period of 3 months. High loading of bupivacaine HCl into the castor oil-based nanoemulsion system was achieved with about 98% entrapment efficiency and the resulting formulation showed high stability under stress conditions (accelerated stability test) regarding changes in visual appearance, drug content, and droplet size. We show herein that the in vitro release and in vivo pharmacokinetic profiles as well as pharmacodynamic outcome (pain relief test) after subcutaneous administration in rats correlate well and clearly demonstrate the prolonged release and extended duration of activity of our novel nanoformulation. In addition, the lower C max value achieved in the blood compartment suggests the possibility that the risk for systemic side effects is reduced. We conclude that castor oil-based nanomulsion represents an attractive pain treatment possibility to achieve prolonged local action of bupivacaine HCl.

  15. Effect of CH3COOH on Hydrometallurgical Purification of Metallurgical-Grade Silicon Using HCl-HF Leaching

    Science.gov (United States)

    Tian, Chunjin; Lu, Haifei; Wei, Kuixian; Ma, Wenhui; Xie, Keqiang; Wu, Jijun; Lei, Yun; Yang, Bin; Morita, Kazuki

    2018-04-01

    The present study investigated the effects of adding CH3COOH to HCl and HF used to purify metallurgical-grade Si (MG-Si). After 6 h of leaching MG-Si with an acid mixture consisting of 4 mol L-1 HCl, 3 mol L-1 HF, and 3 mol L-1 CH3COOH at 348 K, the total impurity removal efficiency was 88.5%, exceeding the 81.5% removal efficiency obtained without addition of CH3COOH. The microstructural evolution of Si after etching with the two lixiviants indicated better dissolution of metal impurities in MG-Si when using the HCl-HF-CH3COOH mixture. Furthermore, the leaching kinetics of Fe using the HCl-HF and HCl-HF-CH3COOH mixtures were observed to depend on the interfacial chemical reactions.

  16. Phase equilibria in a system of aqueous arginine with an octane solution of sulfonic acid

    Science.gov (United States)

    Kuvaeva, Z. I.; Koval'chuk, I. V.; Vodop'yanova, L. A.; Soldatov, V. S.

    2013-05-01

    The extraction of arginine (Arg) from aqueous salt (0.1 M NaCl) solutions with a sulfo extractant in a wide range of pH values and amino acid concentrations was studied. The 0.1 M solution of dinonylnaphthalenesulfonic acid (HD) in octane was used as an extractant. The degree of extraction was found to be high at pH 0.8-9.0. This can be explained by the effect of additional intermolecular interactions in the extractant phase involving the guanidine group of Arg.

  17. Effect of citric acid on the acidification of artificial pepsin solution for metacercariae isolation from fish.

    Science.gov (United States)

    Kim, Min-Ki; Pyo, Kyoung-Ho; Hwang, Young-Sang; Chun, Hyang Sook; Park, Ki Hwan; Ko, Seong-Hee; Chai, Jong-Yil; Shin, Eun-Hee

    2013-11-15

    Artificial digestive solution based on pepsin is essential for collecting metacercariae from fish. To promote the enzymatic reactivity of pepsin, the pH of the solution has to be adjusted to pH 1.0-2.0. Hydrochloride (HCl) is usually used for this purpose, but the use of HCl raises safety concerns. The aim of this work was to address the usefulness of citric acid as an alternative for HCl for the acidification of pepsin solution, and to examine its potential to damage metacercariae during in vitro digestion as compared with HCl. Changes in pH after adding 1-9% of citric acid (m/v) to pepsin solution were compared to a 1% HCl (v/v) addition. Digestion of fish muscle was evaluated by measuring released protein concentrations by spectrophotometry. In addition, survival rates of metacercariae in pepsin solution were determined at different citric acid concentrations and were compared that of with 1% HCl. The present study shows that addition of citric acid reduced the pH of pepsin solutions to the required level. Addition of more than 5% of citric acid resulted in the effective digestion of fish muscle over 3h in vitro, and 5% citric acid was less lethal to metacercariae than 1% HCl in pepsin solution. Pepsin solution containing 5% citric acid had digestive capacity superior to pepsin solution containing 1% HCl after 3h incubation with released protein concentrations of 12.0 ng/ml for 5% citric acid and 9.6 ng/ml for 1% HCl. Accordingly, the present study suggests that the addition of 5% citric acid to pepsin solution is a good alternative to 1% HCl in infection studies because citric acid is a stable at room temperature and has a good safety profile. In addition, we suggest that the use of citric acid enables the preparation of commercial digestive solutions for the detection of microorganisms in fish and other vertebrate muscle tissue. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  18. [Effects of excess pyridoxine-HCl on growth and urinary excretion of water-soluble vitamins in weaning rats].

    Science.gov (United States)

    Fukuwatari, Tsutomu; Itoh, Keiko; Shibata, Katsumi

    2009-04-01

    To determine the tolerable upper intake level of pyridoxine-HCl in humans, we investigated the effects of excess pyridoxine-HCl administration on body weight gain, food intake, tissue weight, and urinary excretion of water-soluble vitamins in weaning rats. The weaning rats were freely fed ordinary diet containing 0.0007% pyridoxine-HCl (control diet) or the same diet with 0.1%, 0.5%, 0.8% or 1.0% pyridoxine-HCl for 30 days. The body weight gain in the 0.8% and 1.0% groups, and the total food intake in the 1.0% group were significantly lower than those in the control group. The urinary excretion of pantothenic acid in the pyridoxine-HCl added groups were higher than that in the control group, while excessive pyridoxine-HCl intake did not affect the urinary excretion of other water-soluble vitamins. These results showed that the no-observed-adverse-effect-level (NOAEL) for pyridoxine-HCl was 0.1% in diet, corresponding to 90 mg/kg body weight/day, and lowest-observed-adverse-effect-level (LOAEL) was 0.5% in diet, corresponding to 450 mg/kg body weight/day.

  19. Chitosan-poly (lactide-co-glycolide) (CS-PLGA) nanoparticles containing metformin HCl: preparation and in vitro evaluation.

    Science.gov (United States)

    Gundogdu, Nuran; Cetin, Meltem

    2014-11-01

    In this study, the preparation and in vitro characterisation of metformin HCl-loaded CS-PLGA nanoparticles (NPs) were aimed. The prepared nanoparticles (blank nanoparticles (C-1), 50 mg of metformin HCl loaded nanoparticles (C-2) and 75 mg of metformin HCl loaded nanoparticles (C-3) ranged in size from 506.67±13.61 to 516.33±16.85 nm and had surface charges of 22.57±1.21 to 32.37±0.57 mV. Low encapsulation efficiency was observed for both nanoparticle formulations due to the leakage of metformin HCl to the external medium during preparation of nanoparticles. Nanoparticle formulations showed highly reproducible drug release profiles. ~20% of metformin HCl was released within 30 minutes and approximately 98% of the loaded metformin HCl was released at 144 hours in a phosphate buffer (PB; pH 6.8). No statistically significant difference was noted between the in vitro release profiles of the nanoparticles (C-2 and C-3) containing metformin HCl. Also, nanoparticles were characterised using FT-IR and DSC.

  20. Determination of prilocaine HCl in bulk drug and pharmaceutical formulation by GC-NPD method

    Directory of Open Access Journals (Sweden)

    Atila Alptug

    2013-01-01

    Full Text Available The novel analytical method was developed and validated for determination of prilocaine HCl in bulk drug and pharmaceutical formulation by gas chromatography-nitrogen phosphorus detection (GC-NPD. The chromatographic separation was performed using a HP-5MS column. The calibration curve was linear over the concentration range of 40-1000 ng ml-1 with a correlation coefficient of 0.9998. The limits of detection (LOD and quantification (LOQ of method were 10 ng ml-1 and 35 ng ml-1, respectively. The within-day and between-day precision, expressed as the percent relative standard deviation (RSD% was less than 5.0%, and accuracy (percent relative error was better than 4.0%. The developed method can be directly and easily applied for determination of prilocaine HCl in bulk drug and pharmaceutical formulation using internal standard methodology.

  1. Analysis of tellurium-silicon alloys. Part 1. Determination of tellurium by the reduction from perchloric acid solution

    International Nuclear Information System (INIS)

    Teperek, J.

    1977-01-01

    When 100-150 mg of tellurium is dissolved in the solution containing 20 cm 3 72 wt.% of perchloric acid, the reduction of tellurium to elementary form is possible only after adding 60-100 milimoles of HCl. The reduction is performed by adding 1 cm 3 of saturated sodium pyrosulphite solution (Na 2 S 2 O 5 ) and 10 cm 3 of 10 wt.% hydrazine hydrochloride solution (N 2 H 4 .2HCl) to 80-90 cm 3 of cold solution of Te in HClO 4 -HCl mixture. The reduction is completed after 3-5 min. of boiling. When 150-200 mg sample of Te-Si alloy is dissolved in 20 cm 3 of hot 72% per chloric acid, the separation of components is reached. Tellurium can be determinated in filtrate by proposed procedure with high accuracy and precision. (author)

  2. V and Nb Influence on the Austenitic Stainless Steel Corrosion in 0.1 M HCl

    Directory of Open Access Journals (Sweden)

    Amel GHARBI

    2014-05-01

    Full Text Available Vanadium and niobium were added in AISI309 austenitic stainless steel composition to modify their structure and pitting corrosion resistance in 0.1 M HCl. The structural characterization was carried out by X-rays diffraction and optical microscopy. Corrosion behavior was investigated using potentiodynamic tests and electrochemical impedance measurements (EIS .Results showed that vanadium and niobium addition precipitated stable carbides (VC, NbC to chromium carbides’ detriment and improved austenitic stainless steel corrosion resistance.

  3. Novel levocetirizine HCl tablets with enhanced palatability: synergistic effect of combining taste modifiers and effervescence technique

    Directory of Open Access Journals (Sweden)

    Labib GS

    2015-09-01

    Full Text Available Gihan S Labib1,2 1Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia; 2Department of Pharmaceutics, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt Objectives: Levocetirizine HCl, a second-generation piperazine derivative and H1-selective antihistaminic agent, possesses few side effects. The first objective of the study was to compare and evaluate the taste-masking effect of different ratios of 2-hydroxypropyl-β-cyclodextrin and mannitol on levocetirizine HCl using an inclusion complex and solid dispersion, respectively. The second objective was to study the possibility of preparing and evaluating effervescent tablets from the best-chosen taste-masked blends for the purpose of their use either as orodispersible tablets or as water-soluble effervescent tablets, according to patients’ will.Materials and methods: Prepared taste-masked blends were prepared and subjected to palatability, Fourier-transform infrared spectroscopy, and differential scanning calorimetry studies. Tablets containing different percentages of effervescent mixtures were prepared by direct compression on the selected taste-modified blends. Evaluation tests were conducted, including flowability and compressibility on the precompressed blends and hardness, friability, wetting time, effervescent time, in vitro, in vivo disintegration time, and in vitro dissolution study on the compressed tablets. Formulated tablets were evaluated and compared to marketed orodispersible tablets for mouth feel and palatability.Results: All prepared tablets showed convenient physical and palatability properties compared to the selected brand. The in vitro drug-release study revealed fast release of levocetirizine HCl within 5 minutes from all prepared tablets.Conclusion: Levocetirizine HCl effervescent tablets are likely to increase patient compliance with drug administration. Moreover, the use of these

  4. Novel levocetirizine HCl tablets with enhanced palatability: synergistic effect of combining taste modifiers and effervescence technique

    Science.gov (United States)

    Labib, Gihan S

    2015-01-01

    Objectives Levocetirizine HCl, a second-generation piperazine derivative and H1-selective antihistaminic agent, possesses few side effects. The first objective of the study was to compare and evaluate the taste-masking effect of different ratios of 2-hydroxypropyl-β-cyclodextrin and mannitol on levocetirizine HCl using an inclusion complex and solid dispersion, respectively. The second objective was to study the possibility of preparing and evaluating effervescent tablets from the best-chosen taste-masked blends for the purpose of their use either as orodispersible tablets or as water-soluble effervescent tablets, according to patients’ will. Materials and methods Prepared taste-masked blends were prepared and subjected to palatability, Fourier-transform infrared spectroscopy, and differential scanning calorimetry studies. Tablets containing different percentages of effervescent mixtures were prepared by direct compression on the selected taste-modified blends. Evaluation tests were conducted, including flowability and compressibility on the precompressed blends and hardness, friability, wetting time, effervescent time, in vitro, in vivo disintegration time, and in vitro dissolution study on the compressed tablets. Formulated tablets were evaluated and compared to marketed orodispersible tablets for mouth feel and palatability. Results All prepared tablets showed convenient physical and palatability properties compared to the selected brand. The in vitro drug-release study revealed fast release of levocetirizine HCl within 5 minutes from all prepared tablets. Conclusion Levocetirizine HCl effervescent tablets are likely to increase patient compliance with drug administration. Moreover, the use of these effervescent tablets in an orodispersible dosage form can improve oral drug bioavailability and act as an attractive pediatric dosage form. PMID:26379426

  5. Stimulation of deep gas wells using HCl/formic acid system : lab studies and field application

    Energy Technology Data Exchange (ETDEWEB)

    Nasr-El-Din, H.A.; Al-Mutairi, S.; Al-Malki, B. [Saudi Aramco (Saudi Arabia); Metcalf, S.; Walters, W. [BJ Services Co USA, Houston, TX (United States)

    2002-06-01

    Well stimulation in the deep carbonate Khuff reservoirs in eastern Saudi Arabia is needed to remove drilling mud filter cakes and to enhance reservoir permeability. A non associated gas is being produced from the reservoirs. This gas is associated with the hydrogen sulfide content that varies from 0 to 10-mol per cent. The average reservoir temperature is 275 degrees F and initial reservoir pressure is 7,000 psi. A special system is needed to stimulate the carbonate reservoir because of this high bottomhole temperature and the corrosive nature of hydrochloric acid (HCl) at high temperature. A rotating disk method was used to determine the reaction rate of an HCl/formic acid system with reservoir rocks. Results from coreflood tests showed that the acid system creates deep wormholes in tight reservoir cores. Corrosion tests showed that the well tubulars could tolerate the acid system. A gelled 15-wt per cent HCl/9-wt per cent formic acid system successfully fractured 3 vertical wells in deep sour gas reservoirs without any operational problems. The treatment resulted in significant increases in gas production and flowing wellhead pressures. In addition, overflush of the treatment successfully eliminated the return of live acid after the treatment. 37 refs., 10 tabs., 17 figs.

  6. Deuterium isotope effects on the dipole moment and polarizability of HCl and NH3

    International Nuclear Information System (INIS)

    Scher, C.; Ravid, B.; Halevi, E.A.

    1982-01-01

    A previously described adaptation of the conventional Debye procedure for the direct determination of small dipole moment and polarizability differences between two polar gases is applied to the isotopic pairs DCl-HCl and ND 3 -NH 3 . The dipole moment difference obtained for the first isotopic pair, by using the Debye-Van Vleck equation for electric susceptibility, μ(DCl) - μ(HCl) = 0.005 5 +/- 0.0002 D, is consistent with published spectroscopically determined values of μ 00 (DCl) and μ 00 (HCl), while that obtained by using the classical Debye equation is not. For the second pair, use of the Debye-Van Vleck equation, along with a correction for thermal population of vibrationally excited levels, is shown to be essential and yields μ(ND) 3 - μ(NH 3 ) = +0.013 5 +/- 0.001 D and α(ND 3 ) - α(NH 3 ) = -(2.2 +/- 1.7) x 10 -26 cm 3

  7. Corrosion inhibition of iota-carrageenan natural polymer on aluminum in presence of zwitterion mediator in HCl media

    International Nuclear Information System (INIS)

    Fares, Mohammad M.; Maayta, A.K.; Al-Mustafa, Jamil A.

    2012-01-01

    Highlights: ► Inhibition of Al by ι-carrageenan in the presence of zwitterion mediator was investigated. ► Considerable improvement in inhibition efficiency observed in the presence of zwitterion mediator. ► Coherent physical adsorption layer was evidenced by kinetic and thermodynamic parameters. ► Small but consistent fractured island layers observed after acid exposure as revealed by SEM images. - Abstract: ι-Carrageenan a natural polymer has been used as corrosion inhibitor of aluminum in presence of pefloxacin mesylate, acting as zwitterionic mediator, in acidic medium. Considerable improvement in inhibition efficiency occurred in the presence of the mediator. Activation energy of corrosion and other thermodynamic parameters such as standard free energy, standard enthalpy, and standard entropy of the adsorption process revealed better and well-ordered physical adsorption layers in presence of pefloxacin. Adsorption isotherms in absence or presence of pefloxacin mediator appropriately fit in the Langmuir isotherms. The scanning electron microscope (SEM) images demonstrated smooth, glossy, and relatively coherent adsorption layers of the inhibitor on the metal surface in aqueous solution. After the exposure to 2.0 M HCl for 2 h, a smaller but consistent regular shaped fractured layer is obtained.

  8. Pharmacological Identification of a Guanidine-Containing β-Alanine Analogue with Low Micromolar Potency and Selectivity for the Betaine/GABA Transporter 1 (BGT1)

    DEFF Research Database (Denmark)

    Al-Khawaja, Anas Mohammad Ali; Petersen, Jette Gellert; Damgaard, Maria

    2014-01-01

    of the amino group in β-alanine or GABA, a series of compounds was generated, and their pharmacological activity assessed at human GAT subtypes. Using a cell-based [(3)H]GABA uptake assay, several selective inhibitors at human BGT1 were identified. The guanidine-containing compound 9 (2-amino-1......,4,5,6-tetrahydropyrimidine-5-carboxylic acid hydrochloride) displayed more than 250 times greater potency than the parent compound β-alanine at BGT1 and is thus the most potent inhibitor reported to date for this subtype (IC50 value of 2.5 µM). In addition, compound 9 displayed about 400, 16 and 40 times lower inhibitory...

  9. Isomers of Poly Aminophenol: Chemical Synthesis, Characterization, and Its Corrosion Protection Aspect on Mild Steel in 1 M HCl

    Directory of Open Access Journals (Sweden)

    G. Thenmozhi

    2014-01-01

    Full Text Available The oxidative chemical polymerizations of three isomers of aminophenol, ortho, meta, and para (PoAP, PmAP, and PpAP, were performed in aqueous HCl using ammonium persulfate as an oxidant at 0–3°C. The synthesized polymers were characterized by employing elemental analysis, GPC, UV-VIS-NIR, FT-IR, XRD, and TGA. The corrosion inhibition effect of these three polymers on mild steel in 1 M HCl solution was studied by using electrochemical techniques such as potentiodynamic polarization and electrochemical impedance spectroscopy. These measurements reveal that the inhibition efficiency obtained by these polymers increased by increasing their concentration. The inhibition efficiency follows the order PpAP > PoAP > PmAP. The results further revealed that PpAP at a concentration of 250 mg/L furnishes maximum inhibition efficiency (96.5%. Polarization studies indicated that these three polymers act as the mixed type corrosion inhibitors.

  10. Synergistic effect of iodide ion addition on the inhibition of mild steel corrosion in 1 M HCl by 3-amino-2-methylbenzylalcohol

    Energy Technology Data Exchange (ETDEWEB)

    Obot, I.B., E-mail: obot@kfupm.edu.sa; Madhankumar, A.

    2016-07-01

    The inhibition of mild steel corrosion in 1 M HCl aqueous solution by 3-amino-2-methylbenzylalcohol (AMBA) was investigated using weight loss, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP) and cyclic voltammametry (CV) techniques. Attenuated total reflectance infrared spectroscopy (ATR-IR), contact angle (CA) and scanning electron microscopy (SEM) measurements were carried out to confirm the adsorption of AMBA on mild steel surface. Computer simulations using density functional theory (DFT) and Monte Carlo methodologies were further employed to provide insights into the mechanism of interaction between the inhibitor and the steel surface. All the results confirmed that AMBA is a good corrosion inhibitor for mild steel in 1 M HCl. The addition of NaI was found to increase the inhibition effect of AMBA on mild steel to a considerable extent. DFT results reveal that the N atom together with the π-systems in the aromatic ring were the active sites for the interaction of AMBA with steel surface. Furthermore, the negative value of the adsorption energy obtained from the Monte Carlo simulation indicates the stability of the adsorbed inhibitor film on the steel surface. - Graphical abstract: EIS spectra and adsorption configuration of AMBA on Fe (110). - Highlights: • 3-amino-2-methylbenzylalcohol inhibit mild steel corrosion in acid medium. • ATR-IR, contact angle, SEM, were used for steel surface characterization. • DFT and Monte Carlo simulations provide atomic and molecular level insights. • The theoretical data clearly support the experimental results obtained.

  11. Synthesis of [11C]dapoxetine·HCl, a serotonin re-uptake inhibitor: biodistribution in rat and preliminary PET imaging in the monkey

    International Nuclear Information System (INIS)

    Livni, E.; Satterlee, W.; Robey, R.L.

    1994-01-01

    [ 11 C]Dapoxetine · HCl, S-(+)-N,N-dimethyl-a-[2-(naphthalenyloxy)ethyl] benzenemethanamine hydrochloride, a potent serotonin re-uptake inhibitor was prepared from its mono-methyl precursor, S-(+)-N-methyl-a-[2-(naphthalenyloxy)ethyl]benzene methanamine hydrochloride. Biodistribution was determined in rats at 5, 30 and 60 min after injection and preliminary PET studies were performed in a Rhesus monkey. 11 CH 3 I was bubbled into a solution of S-(+)-N-methyl-α-[2-(naphthalenyloxy)ethyl]benzene methanamine hydrochloride (3.0 mg in DMSO) and the mixture was heated at 110 o C for 8 min. [ 11 C]Dapoxetine · HCl was purified by HPLC on a C 18 cartridge eluted with MeOH: phosphate buffer, pH 7.2 (75:25) with a 10% yield (end of synthesis). The time required for the synthesis was 40 min, from the end of bombardment. Radiochemical purity of the final product was > 99% and specific activity was routinely > 400 mCi/μmol [EOS]. (author)

  12. Automation of dimethylation after guanidination labeling chemistry and its compatibility with common buffers and surfactants for mass spectrometry-based shotgun quantitative proteome analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Andy; Tang, Yanan; Chen, Lu; Li, Liang, E-mail: Liang.Li@ualberta.ca

    2013-07-25

    Graphical abstract: -- Highlights: •Dimethylation after guanidination (2MEGA) uses inexpensive reagents for isotopic labeling of peptides. •2MEGA can be optimized and automated for labeling peptides with high efficiency. •2MEGA is compatible with several commonly used cell lysis and protein solubilization reagents. •The automated 2MEGA labeling method can be used to handle a variety of protein samples for relative proteome quantification. -- Abstract: Isotope labeling liquid chromatography–mass spectrometry (LC–MS) is a major analytical platform for quantitative proteome analysis. Incorporation of isotopes used to distinguish samples plays a critical role in the success of this strategy. In this work, we optimized and automated a chemical derivatization protocol (dimethylation after guanidination, 2MEGA) to increase the labeling reproducibility and reduce human intervention. We also evaluated the reagent compatibility of this protocol to handle biological samples in different types of buffers and surfactants. A commercially available liquid handler was used for reagent dispensation to minimize analyst intervention and at least twenty protein digest samples could be prepared in a single run. Different front-end sample preparation methods for protein solubilization (SDS, urea, Rapigest™, and ProteaseMAX™) and two commercially available cell lysis buffers were evaluated for compatibility with the automated protocol. It was found that better than 94% desired labeling could be obtained in all conditions studied except urea, where the rate was reduced to about 92% due to carbamylation on the peptide amines. This work illustrates the automated 2MEGA labeling process can be used to handle a wide range of protein samples containing various reagents that are often encountered in protein sample preparation for quantitative proteome analysis.

  13. TCA precipitation and ethanol/HCl single-step purification evaluation: One-dimensional gel electrophoresis, bradford assays, spectrofluorometry and Raman spectroscopy data on HSA, Rnase, lysozyme - Mascots and Skyline data

    Directory of Open Access Journals (Sweden)

    Balkis Eddhif

    2018-04-01

    Full Text Available The data presented here are related to the research paper entitled “Study of a Novel Agent for TCA Precipitated Proteins Washing - Comprehensive Insights into the Role of Ethanol/HCl on Molten Globule State by Multi-Spectroscopic Analyses” (Eddhif et al., submitted for publication [1]. The suitability of ethanol/HCl for the washing of TCA-precipitated proteins was first investigated on standard solution of HSA, cellulase, ribonuclease and lysozyme. Recoveries were assessed by one-dimensional gel electrophoresis, Bradford assays and UPLC-HRMS. The mechanistic that triggers protein conformational changes at each purification stage was then investigated by Raman spectroscopy and spectrofluorometry. Finally, the efficiency of the method was evaluated on three different complex samples (mouse liver, river biofilm, loamy soil surface. Proteins profiling was assessed by gel electrophoresis and by UPLC-HRMS.

  14. Influences of chlorine content on emission of HCl and organic compounds in waste incineration using fluidized beds.

    Science.gov (United States)

    Wey, M Y; Liu, K Y; Yu, W J; Lin, C L; Chang, F Y

    2008-01-01

    HCl and some organic compounds are the precursors of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) in municipal solid waste incinerators. In this work, a lab-scale fluidized bed incinerator is adopted to study the relationship between the organic and the inorganic chlorine contents of artificial wastes and the emissions of HCl and organic compounds. The lower threshold limit (LTL) of chlorine content below which HCl and organic compounds are not generated is studied. Experimental results showed that organic chlorides had a greater potential to release chlorine than inorganic chlorides. The generation of organic pollutants fell, but the emissions of HCl increased with the temperature. The concentrations of chlorophenols (CPs)/chlorobenzenes (CBs) increased with chlorine contents. No LTL existed for HCl regardless of whether CaO was added. The LTL for CPs was between 0.1 and 0.3wt% of inorganic chloride, but there was none for organic sources. For CBs, the LTL was between 0.5 and 1.0wt% for inorganics at 700 and 800 degrees C, but 0.1-0.3 wt% at 700 degrees C and 0.3-0.5 wt% at 800 degrees C for organics. The production of PAHs and benzene, toluene, ethylbenzene and xylene (BTEX) was related to the surplus hydrogen ions that were not reacted with the chlorine. Adding CaO inhibited the production of HCl, CBs and CPs, but did not seriously affect PAHs and BTEX.

  15. Interaction of N-hydroxyurea with strong proton donors: HCl and HF

    International Nuclear Information System (INIS)

    Sałdyka, Magdalena

    2014-01-01

    Highlights: • 1:1 and 1:2 N-hydroxyurea complexes with HCl and HF are trapped in argon matrices. • The complexes are stabilized by strong X–H⋯O bond. • Hydrogen bonds in the cyclic 1:2 complexes show strong cooperativity. • The C=O group is the strongest proton acceptor centre in the N-hydroxyurea molecule. - Abstract: An infrared spectroscopic and MP2/6-311++G(2d,2p) study of strong hydrogen bonded complexes of N-hydroxyurea (NH 2 CONHOH) with hydrogen halides (HCl and HF) trapped in solid argon matrices is reported. 1:1 and 1:2 complexes between N-hydroxyurea and hydrogen chloride, hydrogen fluoride have been identified in the NH 2 CONHOH/HCl/Ar, NH 2 CONHOH/HF/Ar matrices, respectively; their structures were determined by comparison of the spectra with the results of calculations. In the 1:1 complexes, identified for both hydrogen halide molecules, the cyclic structure stabilized by the X–H⋯O and N–H⋯X bonds is present; for the NH 2 CONHOH⋯HF system another isomeric 1:1 complex is also observed. Two 1:2 complexes were identified for the N-hydroxyurea–hydrogen chloride system characterised by the Cl–H⋯O and N–H⋯Cl bonds. The results of the study evidence that N-hydroxyurea is an oxygen base in the gas-phase with the carbonyl group as the strongest proton acceptor centre in the molecule

  16. Interaction of N-hydroxyurea with strong proton donors: HCl and HF

    Energy Technology Data Exchange (ETDEWEB)

    Sałdyka, Magdalena, E-mail: magdalena.saldyka@chem.uni.wroc.pl

    2014-11-24

    Highlights: • 1:1 and 1:2 N-hydroxyurea complexes with HCl and HF are trapped in argon matrices. • The complexes are stabilized by strong X–H⋯O bond. • Hydrogen bonds in the cyclic 1:2 complexes show strong cooperativity. • The C=O group is the strongest proton acceptor centre in the N-hydroxyurea molecule. - Abstract: An infrared spectroscopic and MP2/6-311++G(2d,2p) study of strong hydrogen bonded complexes of N-hydroxyurea (NH{sub 2}CONHOH) with hydrogen halides (HCl and HF) trapped in solid argon matrices is reported. 1:1 and 1:2 complexes between N-hydroxyurea and hydrogen chloride, hydrogen fluoride have been identified in the NH{sub 2}CONHOH/HCl/Ar, NH{sub 2}CONHOH/HF/Ar matrices, respectively; their structures were determined by comparison of the spectra with the results of calculations. In the 1:1 complexes, identified for both hydrogen halide molecules, the cyclic structure stabilized by the X–H⋯O and N–H⋯X bonds is present; for the NH{sub 2}CONHOH⋯HF system another isomeric 1:1 complex is also observed. Two 1:2 complexes were identified for the N-hydroxyurea–hydrogen chloride system characterised by the Cl–H⋯O and N–H⋯Cl bonds. The results of the study evidence that N-hydroxyurea is an oxygen base in the gas-phase with the carbonyl group as the strongest proton acceptor centre in the molecule.

  17. Formulation and Evaluation of Microsphere Based Oro Dispersible Tablets of Itopride Hcl

    Directory of Open Access Journals (Sweden)

    S.S Agrawal

    2012-09-01

    Full Text Available Background The purpose of the present work is to mask the intensely bitter taste of Itopride HCl and to formulate an Oro dispersible tablet (ODT of the taste-masked drug by incorporation of microspheres in the tablets for use in specific populations viz. pediatrics, geriatrics and patients experiencing difficulty in swallowing.Methods:With this objective in mind, microspheres loaded with Itopride HCl were prepared by solvent evaporation method using acetone as solvent for pH-sensitive polymer, Eudragit EPO and light liquid paraffin as the encapsulating medium. The prepared microspheres were characterized with regard to yield, drug content, flow properties, particle size and size distribution, surface features, in vitro drug release and taste. The ODTs so prepared from these microspheres were evaluated for hardness, thickness, weight variation, friability, disintegration time, drug content, wetting time, water absorption ratio, moisture uptake, in vitro dispersion, in vitro disintegration, in vitro drug release and stability. Results:The average size of microspheres was found to be satisfactory in terms of the size and size distribution. Microspheres prepared were of a regular spherical shape. Comparison of the dissolution profiles of microspheres in different pH media showed that microspheres having drug: polymer ratio of 1:2 produced a retarding effect in simulated salivary fluid (pH 6.8 and were further used for formulation into ODTs after addition of suitable amounts of excipients such as superdisintegrant, diluent, sweetener and flavor of directly compressible grade. ConclusionsEffective taste-masking was achieved for Itopride HCl by way of preparation of microspheres and ODTs of acceptable characteristics.

  18. Effect of glucosamine HCl on dissolution and solid state behaviours of piroxicam upon milling.

    Science.gov (United States)

    Al-Hamidi, Hiba; Edwards, Alison A; Douroumis, Dionysis; Asare-Addo, Kofi; Nayebi, Alireza Mohajjel; Reyhani-Rad, Siamak; Mahmoudi, Javad; Nokhodchi, Ali

    2013-03-01

    Piroxicam is a non-steroidal anti-inflammatory drug that is characterised by low solubility and high permeability. In order to improve the drug dissolution rate, the co-grinding method was used as an approach to prepare piroxicam co-ground in the carriers such as glucosamine hydrochloride. As, this amino sugar (glucosamine HCl) has been shown to decrease pain and improve mobility in osteoarthritis in joints, therefore, the incorporation of glucosamine in piroxicam formulations would be expected to offer additional benefits to patients. The effect of the order of grinding on the dissolution of piroxicam was also investigated. Co-ground drug and glucosamine were prepared in different ratios using a ball mill. The samples were then subjected to different grinding times. In order to investigate the effect of the grinding process on the dissolution behaviour of piroxicam, the drug was ground separately in the absence of glucosamine. Mixtures of ground piroxicam and unground D-glucosamine HCl were prepared. Physical mixtures of piroxicam and glucosamine were also prepared for comparison. The properties of prepared co-ground systems and physical mixtures were studied using a dissolution tester, FTIR, SEM, XRPD and DSC. These results showed that the presence of glucosamine HCl can increase dissolution rate of piroxicam compared to pure piroxicam. Generally, all dissolution profiles showed the fastest dissolution rate when ground piroxicam was mixed with unground glucosamine. This was closely followed by the co-grinding of piroxicam with glucosamine where lower grinding times showed the fastest dissolution. The solid state studies showed that the grinding of piroxicam for longer times had no effect on polymorphic form of piroxicam, whereas mixtures of piroxicam-glucosamine ground for longer times (60 min) converted piroxicam polymorph II to polymorph I. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Formulation and evaluation of microsphere based oro dispersible tablets of itopride hcl

    Directory of Open Access Journals (Sweden)

    Shah Sanjay

    2012-09-01

    Full Text Available Abstract Background The purpose of the present work is to mask the intensely bitter taste of Itopride HCl and to formulate an Oro dispersible tablet (ODT of the taste-masked drug by incorporation of microspheres in the tablets for use in specific populations viz. pediatrics, geriatrics and patients experiencing difficulty in swallowing. Methods With this objective in mind, microspheres loaded with Itopride HCl were prepared by solvent evaporation method using acetone as solvent for pH-sensitive polymer, Eudragit EPO and light liquid paraffin as the encapsulating medium. The prepared microspheres were characterized with regard to yield, drug content, flow properties, particle size and size distribution, surface features, in vitro drug release and taste. The ODTs so prepared from these microspheres were evaluated for hardness, thickness, weight variation, friability, disintegration time, drug content, wetting time, water absorption ratio, moisture uptake, in vitro dispersion, in vitro disintegration, in vitro drug release and stability. Results The average size of microspheres was found to be satisfactory in terms of the size and size distribution. Microspheres prepared were of a regular spherical shape. Comparison of the dissolution profiles of microspheres in different pH media showed that microspheres having drug: polymer ratio of 1:2 produced a retarding effect in simulated salivary fluid (pH 6.8 and were further used for formulation into ODTs after addition of suitable amounts of excipients such as superdisintegrant, diluent, sweetener and flavor of directly compressible grade. Conclusions Effective taste-masking was achieved for Itopride HCl by way of preparation of microspheres and ODTs of acceptable characteristics.

  20. Formulation and evaluation of microsphere based oro dispersible tablets of itopride hcl.

    Science.gov (United States)

    Shah, Sanjay; Madan, Sarika; Agrawal, Ss

    2012-09-03

    The purpose of the present work is to mask the intensely bitter taste of Itopride HCl and to formulate an Oro dispersible tablet (ODT) of the taste-masked drug by incorporation of microspheres in the tablets for use in specific populations viz. pediatrics, geriatrics and patients experiencing difficulty in swallowing. With this objective in mind, microspheres loaded with Itopride HCl were prepared by solvent evaporation method using acetone as solvent for pH-sensitive polymer, Eudragit EPO and light liquid paraffin as the encapsulating medium. The prepared microspheres were characterized with regard to yield, drug content, flow properties, particle size and size distribution, surface features, in vitro drug release and taste. The ODTs so prepared from these microspheres were evaluated for hardness, thickness, weight variation, friability, disintegration time, drug content, wetting time, water absorption ratio, moisture uptake, in vitro dispersion, in vitro disintegration, in vitro drug release and stability. The average size of microspheres was found to be satisfactory in terms of the size and size distribution. Microspheres prepared were of a regular spherical shape. Comparison of the dissolution profiles of microspheres in different pH media showed that microspheres having drug: polymer ratio of 1:2 produced a retarding effect in simulated salivary fluid (pH 6.8) and were further used for formulation into ODTs after addition of suitable amounts of excipients such as superdisintegrant, diluent, sweetener and flavor of directly compressible grade. Effective taste-masking was achieved for Itopride HCl by way of preparation of microspheres and ODTs of acceptable characteristics.

  1. The release behavior and kinetic evaluation of tramadol HCl from chemically cross linked Ter polymeric hydrogels.

    Science.gov (United States)

    Malana, Muhammad A; Zohra, Rubab

    2013-01-18

    Hydrogels, being stimuli responsive are considered to be effective for targeted and sustained drug delivery. The main purpose for this work was to study the release behavior and kinetic evaluation of Tramadol HCl from chemically cross linked ter polymeric hydrogels. Ter-polymers of methacrylate, vinyl acetate and acrylic acid cross linked with ethylene glycol dimethacrylate (EGDMA) were prepared by free radical polymerization. The drug release rates, dynamic swelling behavior and pH sensitivity of hydrogels ranging in composition from 1-10 mol% EGDMA were studied. Tramadol HCl was used as model drug substance. The release behavior was investigated at pH 8 where all formulations exhibited non-Fickian diffusion mechanism. Absorbency was found to be more than 99% indicating good drug loading capability of these hydrogels towards the selected drug substance. Formulations designed with increasing amounts of EGDMA had a decreased equilibrium media content as well as media penetrating velocity and thus exhibited a slower drug release rate. Fitting of release data to different kinetic models indicate that the kinetic order shifts from the first to zero order as the concentration of drug was increased in the medium, showing gradual independency of drug release towards its concentration. Formulations with low drug content showed best fitness with Higuchi model whereas those with higher concentration of drug followed Hixson-Crowell model with better correlation values indicating that the drug release from these formulations depends more on change in surface area and diameter of tablets than that on concentration of the drug. Release exponent (n) derived from Korse-Meyer Peppas equation implied that the release of Tramadol HCl from these formulations was generally non-Fickian (n > 0.5 > 1) showing swelling controlled mechanism. The mechanical strength and controlled release capability of the systems indicate that these co-polymeric hydrogels have a great potential to

  2. Solubility of drugs in aqueous polymeric solution: effect of ovalbumin on microencapsulation process.

    Science.gov (United States)

    Aziz, Hesham Abdul; Tan, Yvonne Tze Fung; Peh, Kok Khiang

    2012-03-01

    Microencapsulation of water-soluble drugs using coacervation-phase separation method is very challenging, as these drugs partitioned into the aqueous polymeric solution, resulting in poor drug entrapment. For evaluating the effect of ovalbumin on the microencapsulation of drugs with different solubility, pseudoephedrine HCl, verapamil HCl, propranolol HCl, paracetamol, and curcuminoid were used. In addition, drug mixtures comprising of paracetamol and pseudoephedrine HCl were also studied. The morphology, encapsulation efficiency, particle size, and in vitro release profile were investigated. The results showed that the solubility of the drug determined the ratio of ovalbumin to be used for successful microencapsulation. The optimum ratios of drug, ovalbumin, and gelatin for water-soluble (pseudoephedrine HCl, verapamil HCl, and propranolol HCl), sparingly water-soluble (paracetamol), and water-insoluble (curcuminoid) drugs were found to be 1:1:2, 2:3:5, and 1:3:4. As for the drug mixture, the optimum ratio of drug, ovalbumin, and gelatin was 2:3:5. Encapsulated particles prepared at the optimum ratios showed high yield, drug loading, entrapment efficiency, and sustained release profiles. The solubility of drug affected the particle size of the encapsulated particle. Highly soluble drugs resulted in smaller particle size. In conclusion, addition of ovalbumin circumvented the partitioning effect, leading to the successful microencapsulation of water-soluble drugs.

  3. Depletion of chlorine into HCl ice in a protostellar core. The CHESS spectral survey of OMC-2 FIR 4

    Science.gov (United States)

    Kama, M.; Caux, E.; López-Sepulcre, A.; Wakelam, V.; Dominik, C.; Ceccarelli, C.; Lanza, M.; Lique, F.; Ochsendorf, B. B.; Lis, D. C.; Caballero, R. N.; Tielens, A. G. G. M.

    2015-02-01

    Context. The freezeout of gas-phase species onto cold dust grains can drastically alter the chemistry and the heating-cooling balance of protostellar material. In contrast to well-known species such as carbon monoxide (CO), the freezeout of various carriers of elements with abundances <10-5 has not yet been well studied. Aims: Our aim here is to study the depletion of chlorine in the protostellar core, OMC-2 FIR 4. Methods: We observed transitions of HCl and H2Cl+ towards OMC-2 FIR 4 using the Herschel Space Observatory and Caltech Submillimeter Observatory facilities. Our analysis makes use of state of the art chlorine gas-grain chemical models and newly calculated HCl-H2 hyperfine collisional excitation rate coefficients. Results: A narrow emission component in the HCl lines traces the extended envelope, and a broad one traces a more compact central region. The gas-phase HCl abundance in FIR 4 is 9 × 10-11, a factor of only 10-3 that of volatile elemental chlorine. The H2Cl+ lines are detected in absorption and trace a tenuous foreground cloud, where we find no depletion of volatile chlorine. Conclusions: Gas-phase HCl is the tip of the chlorine iceberg in protostellar cores. Using a gas-grain chemical model, we show that the hydrogenation of atomic chlorine on grain surfaces in the dark cloud stage sequesters at least 90% of the volatile chlorine into HCl ice, where it remains in the protostellar stage. About 10% of chlorine is in gaseous atomic form. Gas-phase HCl is a minor, but diagnostically key reservoir, with an abundance of ≲10-10 in most of the protostellar core. We find the [35Cl]/[37Cl] ratio in OMC-2 FIR 4 to be 3.2 ± 0.1, consistent with the solar system value. Appendices are available in electronic form at http://www.aanda.org

  4. The etomidate analog ET-26 HCl retains superior myocardial performance: Comparisons with etomidate in vivo and in vitro.

    Science.gov (United States)

    Liu, Xingxing; Song, Haibo; Yang, Jun; Zhou, Cheng; Kang, Yi; Yang, Linghui; Liu, Jin; Zhang, Wensheng

    2018-01-01

    (R)-2-methoxyethyl1-(1-phenylethyl)-1H-imidazole-5-carboxylate hydrochloride (ET-26 HCl) is a novel etomidate analogue. The purpose of this study was to characterize whether ET-26 HCl could retain the superior myocardial performance of etomidate in vivo and in vitro. In vivo, the influence of ET-26 HCl and etomidate on the cardiac function of dogs was confirmed using echocardiography and electrocardiogram. In vitro, a Langendorff preparation was used to examine direct myocardial performance in isolated rat hearts, and a whole-cell patch-clamp technique was used to study effects on the human ether-a-go-go-related gene (hERG) channel. In vivo, after a single bolus administration of ET-26 HCl or etomidate, no significant difference in echocardiography and electrocardiogram parameters was observed. No arrhythmia occurred and no QT interval prolongation happened during the study period. In the in vitro Langendorff preparation, none of the cardiac parameters were abnormal, and the hERG recordings showed that ET-26 HCl and etomidate inhibited the tail current of the hERG in a concentration-dependent manner with an IC50 of 742.51 μM and 263.60 μM, respectively. In conclusion, through an in vivo experiment and a whole organ preparation, the current study found that ET-26 HCl can maintain a myocardial performance that is similar to that of etomidate. In addition, the electrophysiology study indicated that ET-26 HCl and etomidate inhibited the hERG at a supra-therapeutic concentration.

  5. Formulation optimization and evaluation of jackfruit seed starch-alginate mucoadhesive beads of metformin HCl.

    Science.gov (United States)

    Nayak, Amit Kumar; Pal, Dilipkumar

    2013-08-01

    The present study deals with the formulation optimization of jackfruit (Artocarpus heterophyllus Lam., family: Moraceae) seed starch (JFSS)-alginate mucoadhesive beads containing metformin HCl through ionotropic gelation using 3(2) factorial design. The effect of sodium alginate to JFSS ratio and CaCl2 concentration on the drug encapsulation efficiency (DEE, %), and cumulative drug release at 10h (R10h, %) was optimized. The optimized beads containing metformin HCl showed DEE of 97.48±3.92%, R10h of 65.70±2.22%, and mean diameter of 1.16±0.11mm. The in vitro drug release from these beads was followed controlled-release (zero-order) pattern with super case-II transport mechanism. The beads were also characterized by SEM and FTIR. The swelling and degradation of these beads were influenced by pH of the test medium. The optimized beads also exhibited good mucoadhesivity and significant hypoglycemic effect in alloxan-induced diabetic rats over prolonged period after oral administration. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Blends of jackfruit seed starch-pectin in the development of mucoadhesive beads containing metformin HCl.

    Science.gov (United States)

    Nayak, Amit Kumar; Pal, Dilipkumar

    2013-11-01

    In this work, calcium pectinate-jackfruit (Artocarpus heterophyllus Lam.) seed starch (JFSS) mucoadhesive beads containing metformin HCl were developed through ionotropic-gelation. Effects of pectin and JFSS amounts on drug encapsulation efficiency (DEE), and cumulative drug release after 10 h (R10 h) were optimized using 3(2) factorial design. The optimized calcium pectinate-JFSS beads containing metformin HCl showed DEE of 94.11 ± 3.92%, R10 h of 48.88 ± 2.02%, and mean diameter of 2.06 ± 0.20 mm. The in vitro drug release from these beads was followed controlled-release (zero-order) pattern with super case-II transport mechanism. The beads were also characterized by SEM and FTIR. The pH of test mediums was found critical for swelling and mucoadhesion of these beads. The optimized calcium pectinate-JFSS beads also exhibited good mucoadhesivity and significant hypoglycemic effect in alloxan-induced diabetic rats over prolonged period after oral administration. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Interaction of N-hydroxyurea with strong proton donors: HCl and HF

    Science.gov (United States)

    Sałdyka, Magdalena

    2014-11-01

    An infrared spectroscopic and MP2/6-311++G(2d,2p) study of strong hydrogen bonded complexes of N-hydroxyurea (NH2CONHOH) with hydrogen halides (HCl and HF) trapped in solid argon matrices is reported. 1:1 and 1:2 complexes between N-hydroxyurea and hydrogen chloride, hydrogen fluoride have been identified in the NH2CONHOH/HCl/Ar, NH2CONHOH/HF/Ar matrices, respectively; their structures were determined by comparison of the spectra with the results of calculations. In the 1:1 complexes, identified for both hydrogen halide molecules, the cyclic structure stabilized by the X-H⋯O and N-H⋯X bonds is present; for the NH2CONHOH⋯HF system another isomeric 1:1 complex is also observed. Two 1:2 complexes were identified for the N-hydroxyurea-hydrogen chloride system characterised by the Cl-H⋯O and N-H⋯Cl bonds. The results of the study evidence that N-hydroxyurea is an oxygen base in the gas-phase with the carbonyl group as the strongest proton acceptor centre in the molecule.

  8. Lifetime broadening of atomic lines produced upon ultrafast dissociation of HCl and HBr

    Energy Technology Data Exchange (ETDEWEB)

    Lablanquie, P., E-mail: pascal.lablanquie@upmc.fr [Sorbonne Universités, UPMC Univ Paris 06, LCPMR, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); CNRS, LCPMR (UMR 7614), 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); Iwayama, H. [UVSOR Facility, Institute for Molecular Science, Okazaki 444-8585 (Japan); Penent, F. [Sorbonne Universités, UPMC Univ Paris 06, LCPMR, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); CNRS, LCPMR (UMR 7614), 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); Soejima, K. [Department of Environmental Science, Niigata University, Niigata 950-2181 (Japan); Shigemasa, E. [UVSOR Facility, Institute for Molecular Science, Okazaki 444-8585 (Japan)

    2014-08-15

    Highlights: • Ultrafast dissociation of HCl is triggered by 2p{sub 3/2} → σ* excitation. • Ultrafast dissociation of HBr is triggered by 3d{sub 5/2} → σ* excitation. • Photoelectron spectroscopy reveals sharp vibrational molecular lines and broad atomic lines. • The profiles of the atomic lines are analyzed in detail. • We extract the lifetime of the inner shell hole in the neutral atomic fragment. - Abstract: Ultrafast dissociation of the HCl and HBr molecules excited respectively to the 2p{sub 3/2} → σ* and 3d{sub 5/2} → σ* resonances are studied with high resolution photoelectron spectroscopy. Sharp vibrational molecular lines and broad atomic lines are observed. The analysis of the profile of the atomic lines gives access to the lifetimes of the inner shell 2p{sub 3/2} hole in the Cl* (2p{sub 3/2}){sup −1} 3s{sup 2}3p{sup 6} configuration, and the inner shell 3d{sub 5/2} hole in the Br* (3d{sub 5/2}){sup −1} 4s{sup 2}4p{sup 6} configuration.

  9. Differentially expressed microRNAs in diapausing versus HCl-treated Bombyx embryos.

    Directory of Open Access Journals (Sweden)

    Wentao Fan

    Full Text Available Differentially expressed microRNAs were detected to explore the molecular mechanisms of diapause termination. The total small RNA of diapause-destined silkworm eggs and HCl-treated eggs was extracted and then sequenced using HiSeq high-throughput method. 44 novel miRNAs were discovered. Compared to those in the diapause-destined eggs, 61 miRNAs showed significant changes in the acid-treated eggs, with 23 being up-regulated and 38 being down-regulated. The potential target genes of differentially expressed miRNAs were predicted by miRanda. Gene Ontology and KEGG pathway enrichment analysis of these potential target genes revealed that they were mainly located within cells and organelles, involved in cellular and metabolic processes, and participated in protein production, processing and transportation. Two differentially expressed genes, Bombyx mori SDH and Bmo-miR-2761-3p, were further analyzed with qRT-PCR. BmSDH was significantly up-regulated in the HCl-treated eggs, while Bmo-miR-2761-3p was down-regulated. These results suggested that these two genes were well coordinated in silkworm eggs. Dual luciferase reporter assay demonstrated that Bmo-miR-2761-3p inhibited the expression of BmSDH.

  10. Protective effect of bovine milk against HCl and ethanol-induced gastric ulcer in mice.

    Science.gov (United States)

    Yoo, Jeong-Hyun; Lee, Jeong-Sang; Lee, You-Suk; Ku, SaeKwang; Lee, Hae-Jeung

    2018-05-01

    The purpose of this study was to investigate the gastroprotective effects of bovine milk on an acidified ethanol (HCl-ethanol) mixture that induced gastric ulcers in a mouse model. Mice received different doses of commercial fresh bovine milk (5, 10, and 20 mL/kg of body weight) by oral gavage once a day for 14 d. One hour after the last oral administration of bovine milk, the HCl-ethanol mixture was orally intubated to provoke severe gastric damage. Our results showed that pretreatment with bovine milk significantly suppressed the formation of gastric mucosa lesions. Pretreatment lowered gastric myeloperoxidase and increased gastric mucus contents and antioxidant enzymes catalase and superoxide dismutase. Administration of bovine milk increased nitrate/nitrite levels and decreased the malondialdehyde levels and the expression of proinflammatory genes, including transcription factor nuclear factor-κB, cyclooxygenase-2, and inducible nitric oxide synthase in the stomach of mice. These results suggest that bovine milk can prevent the development of gastric ulcer caused by acid and alcohol in mice. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  11. A Simple RP-HPLC Method for Quantitation of Itopride HCl in Tablet Dosage Form.

    Science.gov (United States)

    Thiruvengada, Rajan Vs; Mohamed, Saleem Ts; Ramkanth, S; Alagusundaram, M; Ganaprakash, K; Madhusudhana, Chetty C

    2010-10-01

    An isocratic reversed phase high-performance liquid chromatographic method with ultraviolet detection at 220 nm has been developed for the quantification of itopride hydrochloride in tablet dosage form. The quantification was carried out using C(8) column (250 mm × 4.6 mm), 5-μm particle size SS column. The mobile phase comprised of two solvents (Solvent A: buffer 1.4 mL ortho-phosphoric acid adjusted to pH 3.0 with triethyl amine and Solvent B: acetonitrile). The ratio of Solvent A: Solvent B was 75:25 v/v. The flow rate was 1.0 mL (-1)with UV detection at 220 nm. The method has been validated and proved to be robust. The calibration curve was linear in the concentration range of 80-120% with coefficient of correlation 0.9995. The percentage recovery for itopride HCl was 100.01%. The proposed method was validated for its selectivity, linearity, accuracy, and precision. The method was found to be suitable for the quality control of itopride HCl in tablet dosage formulation.

  12. Quasiclassical R-matrix theory of inelastic processes in collisions of electrons with HCl molecules

    International Nuclear Information System (INIS)

    Fabrikant, I.I.

    1991-01-01

    The R-matrix theory for the vibrational excitation and dissociative attachment in e-HCl collisions is developed. Only one pole in the R-matrix expansion is included. This allows for making a connection between the R-matrix and the nonlocal-complex-potential theories, and for obtaining the expression for the dissociative-attachment cross section without using the R-matrix radius in the internuclear coordinate. All matrix elements in the equation for the vibrational-excitation and dissociative-attachment amplitudes are calculated using the quasiclassical approach. We study how the results depend on the number of vibrational levels of the neutral molecule included in the theory and show how to exclude the vibrational continuum by a modification of the nonlocal-complex potential. The results for the vibrational-excitation cross sections are extremely sensitive to the behavior of the R-matrix potential curve near the point of crossing this curve with the potential curve of the neutral molecule. Particularly in some cases the cross section at the threshold peak exhibits the boomerang oscillations earlier found for HCl by Domcke [in Aspects of Electron-Molecule Scattering and Photoionization, edited by A. Herzenberg (AIP, New Haven, 1989), p. 169]. The dissociative-attachment cross sections are in reasonable agreement with experiment and with other theories

  13. Development of modified release diltiazem HCl tablets using composite index to identify optimal formulation.

    Science.gov (United States)

    Gohel, M C; Patel, M M; Amin, A F

    2003-05-01

    This article reports the preparation of tartaric acid treated ispaghula husk powder for the development of modified release tablets of diltiazem HCl by adopting direct compression technique and a 32 full factorial design. The modified ispaghula husk powder showed superior swelling and gelling as compared to untreated powder. Addition of compaction augmenting agent such as dicalcium phosphate was found to be essential for obtaining tablets with adequate crushing strength. In order to improve the crushing strength of diltiazem HCl tablets, to modulate drug release pattern, and to obtain similarity of dissolution profiles in distilled water and simulated gastric fluid (pH 1.2), modified guar gum was used along with modified ispaghula husk powder and tartaric acid. A novel composite index, which considers a positive or a negative deviation from an ideal value, was calculated considering percentage drug release in 60, 300, and 540 min as dependent variables for the selection of a most appropriate batch. Polynomial equation and contour plots are presented. The concept of similarity factor (f2) was used to prove similarity of dissolution in water and simulated gastric fluid (pH 1.2).

  14. Physicochemistry of the plasma-electrolyte solution interface

    International Nuclear Information System (INIS)

    Chen Qiang; Saito, Kenji; Takemura, Yu-ichiro; Shirai, Hajime

    2008-01-01

    The atmospheric rf plasma discharge was successfully investigated using NaOH or HCl electrolyte solutions as a counter electrode at different pH values. The emission intensities of solution components, self bias, and electron density strongly depend on the pH value of electrolyte. An addition of ethanol to the electrolyte solutions enhanced the dehydration, which markedly promoted the emissions of solution components as well as electrons from the solution. An acidification of the solution was always observed after the plasma exposure and two coexisting mechanisms were proposed to give a reasonable interpretation. The plasma-electrolyte interface was discussed based on a model of hydrogen cycle

  15. Observed and simulated time evolution of HCl, ClONO2, and HF total column abundances

    Directory of Open Access Journals (Sweden)

    B.-M. Sinnhuber

    2012-04-01

    Full Text Available Time series of total column abundances of hydrogen chloride (HCl, chlorine nitrate (ClONO2, and hydrogen fluoride (HF were determined from ground-based Fourier transform infrared (FTIR spectra recorded at 17 sites belonging to the Network for the Detection of Atmospheric Composition Change (NDACC and located between 80.05° N and 77.82° S. By providing such a near-global overview on ground-based measurements of the two major stratospheric chlorine reservoir species, HCl and ClONO2, the present study is able to confirm the decrease of the atmospheric inorganic chlorine abundance during the last few years. This decrease is expected following the 1987 Montreal Protocol and its amendments and adjustments, where restrictions and a subsequent phase-out of the prominent anthropogenic chlorine source gases (solvents, chlorofluorocarbons were agreed upon to enable a stabilisation and recovery of the stratospheric ozone layer. The atmospheric fluorine content is expected to be influenced by the Montreal Protocol, too, because most of the banned anthropogenic gases also represent important fluorine sources. But many of the substitutes to the banned gases also contain fluorine so that the HF total column abundance is expected to have continued to increase during the last few years. The measurements are compared with calculations from five different models: the two-dimensional Bremen model, the two chemistry-transport models KASIMA and SLIMCAT, and the two chemistry-climate models EMAC and SOCOL. Thereby, the ability of the models to reproduce the absolute total column amounts, the seasonal cycles, and the temporal evolution found in the FTIR measurements is investigated and inter-compared. This is especially interesting because the models have different architectures. The overall agreement between the measurements and models for the total column abundances and the seasonal cycles is good. Linear trends of HCl, ClONO2, and HF are calculated from both

  16. Detecting Hydrogen Chloride (HCl) in the Polluted Marine Boundary Layer Using Cavity Ring-Down Spectroscopy (CRDS)

    Science.gov (United States)

    Furlani, T.; Dawe, K.; VandenBoer, T. C.; Young, C.

    2017-12-01

    Oxidation initiated with chlorine atoms yields more ozone than oxidation initiated with hydroxyl radicals. Reasons for this are not fully understood, but the implications for mechanisms of oxidation chemistry are significant.1,2 Chlorine atoms have not been directly measured to date in the atmosphere and its abundance is usually inferred through steady-state approximations from all known formation and loss processes. A major reservoir for chlorine in the troposphere is by proton abstraction of organic compounds to form HCl.3 HCl can also be formed heterogeneously via acid displacement reactions with ubiquitously-found sodium chloride (NaCl) on solid surfaces with nitric acid (HNO3). The majority of the available chloride in the marine boundary layer comes from the sea salt in and around marine derived sea-spray aerosols. HCl is not a perfect sink and can react with hydroxyl radicals or be photolyzed to form chlorine atoms. The balance between loss and formation processes of chlorine atoms from HCl is highly dependent on many external factors, such as the wet and dry deposition rate of HCl. Measuring HCl in the gas and aerosol phase is important to the understanding of chlorine chemistry in the polluted marine boundary layer. HCl levels in the polluted marine boundary layer are typically between 100pptv-1ppbv,3 requiring the sensitive and selective detection capabilities of cavity ring-down spectroscopy (CRDS).4 We measured HCl using a Picarro CRDS in the polluted marine boundary layer for the first time. Measurements were conducted during April and May of 2017 in St. John's, Newfoundland and Labrador. The performance of the instrument will be discussed, as well as observations of HCl in the context of local conditions. References1Osthoff, H. D. et al. Nat. Geosci 1, 324-328 (2008). 2Young, C. J. et al. Atmos. Chem. Phys. 14, 3427-3440 (2014). 3Crisp, T. a et al. J. Geophys. Res. Atmos. 6897-6915 (2014). 4Hagen, C. L. et al. Atmos. Meas. Tech. 7, 345-357 (2014).

  17. Lead speciation in 0.1N HCl-extracted residue of analog of Pb-contaminated soil

    International Nuclear Information System (INIS)

    Wei Yuling; Yang, Y.-W.; Lee, J.-F.

    2005-01-01

    The heavy metal in-taken by plants from contaminated soils is usually assessed by extraction with 0.1N HCl. This study characterized the chemical form of lead in the solid residue of 0.1N HCl-extracted Pb-contaminated kaolin. The results indicate that most lead in the 0.1N HCl-extracted residue of the Pb(NO 3 ) 2 -contaminated kaolin dried at 105 deg C is mainly in form of PbCl 2 . For other lead-containing kaolin sample heated at 900 deg C, the XAS analysis also shows that majority of the lead compound was converted into PbCl 2 precipitate that remained in the solid residue during the 0.1N HCl extraction. Because PbCl 2 is only slightly soluble in dilute acids or water, it is suggested that using 0.1N HCl liquid as an extracting reagent to represent the heavy metal uptake by plants might actually underestimate the uptake

  18. The attachment of V79 and human periodontal ligament fibroblasts on periodontally involved root surfaces following treatment with EDTA, citric acid, or tetracycline HCL: an SEM in vitro study.

    Science.gov (United States)

    Chandra, R Viswa; Jagetia, Ganesh Chandra; Bhat, K Mahalinga

    2006-02-15

    The present in vitro study has been designed to establish and compare the effects of citric acid, EDTA, and tetracycline HCl on human periodontally diseased roots on the structure, attachment, and orientation of V79 (primary Chinese hamster lung fibroblasts) cells and human periodontal ligament fibroblasts (HPDL). Commercially available V79 cells and HPDL derived from healthy human third molars were used in this study. These fibroblasts were left in solution for seven days in order to attain confluence. Forty single-rooted teeth were obtained from patients diagnosed with periodontitis. The crown part was removed under constant irrigation and the root was split vertically into two equal halves, thus, yielding 80 specimens. Following scaling and root planing, the specimens were washed with phosphate buffered saline (PBS) and kept in 50 microg/ml gentamycin sulphate solution for 24 hours. The root pieces were then treated as follows: citric acid at pH 1, 24% EDTA, or with a 10% solution of tetracycline HCl and were then placed in V79 fibroblast cultures and HPDL cultures. The specimens were harvested after four weeks and were fixed in 2.5% glutaraldehyde in PBS before preparation for scanning electron microscopy (SEM). The behavior of V79 cells was similar to that of human periodontal ligament cells on root conditioned surfaces. V79 and HPDL showed a healthy morphology on root surfaces treated with citric acid and EDTA and a relatively unhealthy appearance on root surfaces treated with tetracycline HCl and distilled water (control group). The results suggest the use of citric acid and EDTA as root conditioning agents favorably affects the migration, attachment, and morphology of fibroblasts on human root surfaces, which may play a significant role in periodontal healing and regeneration.

  19. Vapor-phase etching of InP using anhydrous HCl and PH/sub 3/ gas

    International Nuclear Information System (INIS)

    Pak, K.; Koide, Y.; Imai, K.; Yoshida, A.; Nakamura, T.; Yasuda, Y.; Nishinaga, T.

    1986-01-01

    In situ etching of the substrate surface for vapor-phase epitaxy is a useful technique for obtaining a smooth and damage-free surface prior to the growth. Previous work showed that the incorporation of in situ etching of InP substrate with anhydrous HCl gas resulted in a significant improvement in the surface morphologies for MOVPE-grown InGaAs/InP and InP epitaxial layers. However, the experiment on the HCl etching of the InP substrate for a wide temperature range has not been performed as yet. In this note, the authors describe the effect of the substrate temperature on the etching morphology of InP substrate by using the anhydrous HCl and PH/sub 3/ gases. In the experiment, they used a standard MOVPE horizontal system. A quartz reactor tube in a 60 mm ID, 60 cm long, was employed

  20. Evaluation of pomegranate rind (Punica granatum hydroethanolic extract on blood parameters in male mice treated by Irinotecan Hcl

    Directory of Open Access Journals (Sweden)

    N Mirazi

    2015-05-01

    Full Text Available Background & aim: Irinotecan Hcl is the first order drug for some neoplasm treatment in patients. Irinotecan Hcl has side effects on blood such as anemia and leukopeny. The aim of this study was to evaluate erythropoetic effects of the pomegranate hydroethanolic extract were examined on mice which treated by irinotecan Hcl. Methods: In this experimental study, 49 male mice (25-30 g were divided in 7 groups (control, sham, treated by irinotecan Hcl (100 mg/kg, treated by pomegranate extract (100 and 400 mg/kg, i.p, daily for one week and treated by irinotecan Hcl plus pomegranate extract (100 and 400 mg/kg, i.p, daily for one week randomly. Anemia induced by administration of irinotecan in the experimental animal. At the end of experiment the blood samples were collected by cardiac puncture method and analized for RBC, WBC, Hb, Hct parameters. Data were analyzed using one-way ANOVA and Tukey’s test. Results: The results of this study showed that irinotecan has affected on blood factors and cause to significance decrese compared with control group (p<0.001. Also groups which treated with pomegranate extract (100 and 400 mg/kg significantly reduce the side effects of irinotecan and cause to increasing in blood factors (p<0.001. The number of WBC counts in the group which received Irinotecan (100 kg significantly decreased as compared with the control group (p<0.001. Irinotecan affected on blood Hb level and cause to significant decrease compared with control group. Groups which received pomegranate extract (100 and 400 kg had positive effect and significantly increased the blood Hb levels as compared to controls (p<0.001. Conclusion: These results showed that consumption of pomegranate rind extract in a dose-dependent manner has protective effect on blood parameters in mice which treated with Irinotecan Hcl.

  1. Mass transfer ranking of polylysine, poly-ornithine and poly-methylene-co-guanidine microcapsule membranes using a single low molecular mass marker

    Directory of Open Access Journals (Sweden)

    Rosinski Stefan

    2003-01-01

    Full Text Available On the long way to clinical transplantable hybrid systems, comprising of cells, acting as immuno-protected bioreactors microencapsulated in a polymeric matrix and delivering desired factors (proteins, hormones, enzymes etc to the patient's body, an important step is the optimization of the microcapsule. This topic includes the selection of a proper coating membrane which could fulfil, first of all, the mass transfer as well as biocompatibility, stability and durability requirements. Three different membranes from polymerised aminoacids, formed around exactly identical alginate gel cores, were considered, concerning their mass transport properties, as potential candidates in this task. The results of the evaluation of the mass ingress and mass transfer coefficient h for the selected low molecular mass marker, vitamin B12, in poly-L-lysine (HPLL poly-L-ornithine (HPLO and poly-methylene-co-guanidine hydrochloride (HPMCG membrane alginate microcapsules demonstrate the advantage of using the mass transfer approach to a preliminary screening of various microcapsule formulations. Applying a single marker and evaluating mass transfer coefficients can help to quickly rank the investigated membranes and microcapsules according to their permeability. It has been demonstrated that HPLL, HPLO and HPMCG microcapsules differ from each other by a factor of two concerning the rate of low molecular mass marker transport. Interesting differences in mass transfer through the membrane in both directions in-out was also found, which could possibly be related to the membrane asymmetry.

  2. Quantitative analysis of polyhexamethylene guanidine (PHMG) oligomers via matrix-assisted laser desorption/ionization time-of-flight mass spectrometry with an ionic-liquid matrix.

    Science.gov (United States)

    Yoon, Donhee; Lee, Dongkun; Lee, Jong-Hyeon; Cha, Sangwon; Oh, Han Bin

    2015-01-30

    Quantifying polymers by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) with a conventional crystalline matrix generally suffers from poor sample-to-sample or shot-to-shot reproducibility. An ionic-liquid matrix has been demonstrated to mitigate these reproducibility issues by providing a homogeneous sample surface, which is useful for quantifying polymers. In the present study, we evaluated the use of an ionic liquid matrix, i.e., 1-methylimidazolium α-cyano-4-hydroxycinnamate (1-MeIm-CHCA), to quantify polyhexamethylene guanidine (PHMG) samples that impose a critical health hazard when inhaled in the form of droplets. MALDI-TOF mass spectra were acquired for PHMG oligomers using a variety of ionic-liquid matrices including 1-MeIm-CHCA. Calibration curves were constructed by plotting the sum of the PHMG oligomer peak areas versus PHMG sample concentration with a variety of peptide internal standards. Compared with the conventional crystalline matrix, the 1-MeIm-CHCA ionic-liquid matrix had much better reproducibility (lower standard deviations). Furthermore, by using an internal peptide standard, good linear calibration plots could be obtained over a range of PMHG concentrations of at least 4 orders of magnitude. This study successfully demonstrated that PHMG samples can be quantitatively characterized by MALDI-TOFMS with an ionic-liquid matrix and an internal standard. Copyright © 2014 John Wiley & Sons, Ltd.

  3. Synthesis and biological evaluation of tricyclic guanidine analogues of batzelladine K for antimalarial, antileishmanial, antibacterial, antifungal, and anti-HIV activities.

    Science.gov (United States)

    Ahmed, Nafees; Brahmbhatt, Keyur G; Khan, Shabana I; Jacob, Melissa; Tekwani, Babu L; Sabde, Sudeep; Mitra, Debashis; Singh, Inder P; Khan, Ikhlas A; Bhutani, Kamlesh K

    2013-04-01

    Fifty analogues of batzelladine K were synthesized and evaluated for in vitro antimalarial (Plasmodium falciparum), antileishmanial (Leishmania donovani), antimicrobial (panel of bacteria and fungi), antiviral (HIV-1) activities. Analogues 14h and 20l exhibited potential antimalarial activity against chloroquine-sensitive D6 strain with IC(50) 1.25 and 0.88 μM and chloroquine-resistant W2 strain with IC(50) 1.64 and 1.07 μM, respectively. Analogues 12c and 14c having nonyl substitution showed the most potent antileishmanial activity with IC(50) 2.39 and 2.78 μM and IC(90) 11.27 and 12.76 μM, respectively. Three analogues 12c, 14c, and 14i were the most active against various pathogenic bacteria and fungi with IC(50) Analogue 20l having pentyl and methyl substituents on tricycle showed promising activities against all pathogens. However, none was found active against HIV-1. Our study demonstrated that the tricyclic guanidine compounds provide new structural class for broad spectrum activity. © 2012 John Wiley & Sons A/S.

  4. Radiation-chemical oxidation of neptunium in perchloric acid solutions

    International Nuclear Information System (INIS)

    Shilov, V.P.; Gusev, Yu.K.; Pikaev, A.K.; Stepanova, E.S.; Krot, N.N.

    1979-01-01

    The γ-radiation effect (at a dose rate of 5x10 16 eV/mlxs) on 1x10 -3 Np(6) and Np(5) perchloric acid solutions is studied. The output of Np(6) loss in aerated 0.001-0.005M HClO 4 solutions was 2.4 ions/100 eV. The output of Np(5) loss in solutions saturated with nitrous oxide was 2.1 ions/100 eV at pH-4. In aerated 0.1-1.0 M HClO 4 solutions in presence of XeO 4 the output of Np(5) loss grows from 6.6 to 13.5 ions/100 eV as (XeO 3 ) 0 increases from 1x10 -3 to 2x10 -2 M. Possible process mechanisms have been proposed

  5. EKSTRAKSI PEKTIN DARI KULIT PISANG KEPOK (Musa paradisiaca MENGGUNAKAN PELARUT HCl SEBAGAI EDIBLE FILM

    Directory of Open Access Journals (Sweden)

    Megawati Megawati

    2016-06-01

    Full Text Available Pisang merupakan buah yang sering dikonsumsi oleh manusia, baik secara langsung setelah buahnya matang ataupun diolah menjadi makanan lain. Kulit pisang biasanya hanya dibuang menjadi limbah, padahal didalam pisang terdapat kandungan pektin sebanyak 22,4%. Pada penelitian ini dilakukan ekstraksi pektin dengan bahan dasar kulit pisang yang bertujuan untuk mengetahui jenis pisang yang banyak mengandung pektin, pengaruh variasi bahan serta jenis pelarut yang menghasilkan pektin maksimum. Percobaan dilakukan memakai pisang kepok yang dikeringkan dan diekstraksi menggunakan pelarut dengan suhu ekstraksi 600 W, variasi berat bahan 10 dan 15 gram dengan waktu ekstraksi 20 menit. Dengan pelarut HCl. Hasil ekstraksi ditambahkan dengan etanol hingga terbentuk endapan, kemudian disaring dan di oven pada suhu 65 0C sampai berat konstan. Hasil penelitian menunjukkan bahwa menggunakan metode MAE kadar yield nya yaitu 16,53% lebih besar daripada menggunakan metode konvensional kadar yield nya yaitu 12,8%.

  6. A 223-nm KrCl excimer laser on a He-Kr-HCl mixture

    International Nuclear Information System (INIS)

    Razhev, A M; Zhupikov, A A; Kargapol'tsev, E S

    2004-01-01

    The results of experimental studies of the parameters of a 223-nm electric-discharge KrCl excimer laser on a He-Kr-HCl mixture depending on the excitation conditions and the composition of the active gaseous medium are presented. To achieve the maximum values of the output energy and the efficiency of the KrCl laser on mixtures with buffer gaseous helium, an excitation system was used that included a circuit with an LC inverter with a high-voltage switch based on an RU-65 spark gap. An output energy of 320 mJ with an efficiency of 0.5% relative to the energy stored in the capacitors is obtained in a KrCl laser with an active medium based on the buffer He gas at a charging voltage of 30 kV. Radiation pulses with a duration of 22±1 ns and a pulse power of 15 MW are obtained. (lasers)

  7. Corrosion inhibition efficiency of linear alkyl benzene derivatives for carbon steel pipelines in 1M HCl

    Directory of Open Access Journals (Sweden)

    A.M. Al-Sabagh

    2011-06-01

    Full Text Available Linear alkyl benzene sulfonic acid (L and three of its ester derivatives (L1, L2, L3 were prepared, followed by quaternization of these esters (L1Q, L2Q, L3Q. The corrosion inhibition effect on carbon steel in 1 M HCl was studied using weight loss and potentiodynamic polarization measurements. The adsorption of the inhibitors on carbon steel surface obeyed the Langmuir’s adsorption isotherm. The associated activation energy of corrosion and other thermodynamic parameters such as enthalpy (ΔH∗, entropy (ΔS∗ of activation, adsorption–desorption equilibrium constant (Kads, standard free energy of adsorption (ΔGoads, heat (ΔHoads, and entropy of adsorption (ΔSoads were calculated to elaborate the corrosion inhibition mechanism.

  8. Interactions of aerosols (ammonium sulfate, ammonium nitrate and ammonium chloride) and of gases (HCl, HNO 3) with fogwater

    Science.gov (United States)

    Ruprecht, Heidi; Sigg, Laura

    The concentrations of aerosols (NH 4NO 3, (NH 4) 2SO 4 and NH 4Cl) and of gases (HCl (g), HNO 3(g), NH 3(g) were determined by denuder methods under different conditions (in the absence of fog, before, during and after fog events). At this site situated in an urban region, high concentrations of the gaseous strong acids HCl (g) and HNO 3(g) are observed. NH 4Cl and NH 4NO 3 aerosols represent a major fraction of the Cl - and NO 3- aerosols (fogwater and are released again after fog dissipation.

  9. Semi-interpenetrating hybrid membranes containing ADOGEN{sup ®} 364 for Cd(II) transport from HCl media

    Energy Technology Data Exchange (ETDEWEB)

    Mora-Tamez, Lucía; Rodríguez de San Miguel, Eduardo; Briones-Guerash, Ulrich; Munguía-Acevedo, Nadia M.; Gyves, Josefina de, E-mail: degyves@unam.mx

    2014-09-15

    Graphical abstract: - Highlights: • Semi-interpenetrating hybrid membranes are used for quantitative cadmium(II) recovery. • Optimization of membrane and solutions compositions is performed. • Membranes present increased stability respect to polymer inclusion membranes. • Models for cadmium (II) extraction and transport are proposed. • Excellent selectivity for Cd(II) over Ni(II), Cu(II) and Pb(II) was achieved. - Abstract: Cd(II) transport from 1 mol dm{sup −3} HCl media was investigated across semi-interpenetrating hybrid membranes (SIHMs) that were prepared by mixing an organic matrix composed of ADOGEN{sup ®} 364 as an extracting agent, cellulose triacetate as a polymeric support and nitrophenyloctyl ether as a plasticizer with an organic/inorganic network (silane phase, SP) composed of polydimethylsiloxane and a crosslinking agent. The stripping phase used was a 10{sup −2} mol dm{sup −3} ethanesulfonic acid solution. The effects of tetraorthoethoxysilane, phenyltrimethoxysilane and N′,N′-bis[3-tri(methoxysilyl)propyl]ethylendiamine as crosslinking agents on the transport were studied. H{sub 3}PO{sub 4} was used as an acid catalyst during the SP synthesis and optimized for transport performance. Solid–liquid extraction experiments were performed to determine the model that describe the transport of Cd(II) via ADOGEN{sup ®} 364. The transport was found to be chained-carrier controlled with a percolation threshold of 0.094 mmol g{sup −1}. The selective recovery of Cd(II) was studied with respect to Ni(II), Zn(II), Cu(II), and Pb(II) at a 1:1 molar ratio, and the optimized membrane system was applied for the recovery of Cd(II) from a real sample consisting of a Ni/Cd battery with satisfactory results. Finally, stability experiments were performed using the same membrane for 14 cycles. The results obtained showed that SIHMs had excellent stability and selectivity, with permeabilities comparable to those of PIMs.

  10. Emissions monitoring in conveyed gas flow: (a) sulfur oxides and nitrogen oxides expressed respectively as SO{sub 2} and NO{sub 2}, (b) inorganic chlorine and fluorine compounds as gases and vapours expressed as HCl and HF; Rilevamento delle emissioni in flussi gassosi convogliati: (a) ossidid di zolfo e ossidi di azoto espressi rispettivamente come SO{sub 2} e NO{sub 2}, (b) composti inorganici del cloro e del fluoro sotto forma di gas e vapore espressi rispettivamente come HCl e HF

    Energy Technology Data Exchange (ETDEWEB)

    Ziemacki, G.; Viviano, G. [ed.] [Isituto Superiore di Sanita`, Rome (Italy). Gruppo di lavoro `Modifiche per il rilevamento delle emissioni in atmosfera da impianti industriali`

    1998-03-01

    The method (a) enables the determination of sulfur oxides (SO{sub 2}) and nitrogen oxides (NO{sub 2}) in conveyed atmospheric emissions. A stream of flue gas is a sampled by a heated with a filter housing and absorbed by an alkaline solution of potassium permanganate. The absorption solution is analyzed by ion-exchange chromatography for the determination of sulfate ion and nitrate ion as SO{sub 2} and NO{sub 2}. The method (b) enables the determination of hydrochloric acid (HCl) and hydrofluoric acid (HF) in conveyed atmospheric emissions. A stream of flue gas is sampled by a heated probe with a filter housing and absorbed by an alkaline solution (NaOH). The absorption solution is analyzed by ion-exchange chromatography for the determination of chloride ion and fluoride ion as HCl and HF. [Italiano] Il metodo a) consente la determinazione, in emissioni atmosferiche convogliate, degli ossidi di zolfo (SO{sub 2}) e degli ossidi di azoto (NO{sub 2}). Il campionamento viene effettuato mediante sonda riscaldata, munita di sistema filtrante, e sistema di assorbimento in soluzione alcalina di permanganato di potassio. La soluzione di assorbimento viene analizzata mediante cromatografia a scambio ionico, determinando le concentrazioni di ioni solfato e nitrato come SO{sub 2} ed NO{sub 2}. Il metodo b) consente la determinazione, in emissioni atmosferiche convogliate, dell`acido cloridrico (HCl) e dell`acido fluoridrico (HF). Il campionamento viene effettuato mediante sonda riscaldata, munita di sistema filtrante, e sistema di assorbimento in soluzione alcalina (NaOH). La soluzione alcalina viene quindi analizzata mediante cromatografia a scambio ionico, deter,mminando le concentrazioni di ioni cloro e fluoro come HCl e HF.

  11. Theoretical and experimental studies on the corrosion inhibition potentials of some purines for aluminum in 0.1 M HCl.

    Science.gov (United States)

    Eddy, Nnabuk O; Momoh-Yahaya, H; Oguzie, Emeka E

    2015-03-01

    Experimental aspect of the corrosion inhibition potential of adenine (AD), guanine (GU) and, hypoxanthine (HYP) was carried out using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) methods while the theoretical aspect of the work was carried out by calculations of semi-empirical parameters (for AM1, MNDO, CNDO, PM3 and RM1 Hamiltonians), Fukui functions and inhibitor-metal interaction energies. Results obtained from the experimental studies were in good agreement and indicated that adenine (AD), guanine (GU) and hypoxanthine (HYP) are good adsorption inhibitors for the corrosion of aluminum in solutions of HCl. Data obtained from electrochemical experiment revealed that the studied purines functioned by adsorption on the aluminum/HCl interface and inhibited the cathodic half reaction to a greater extent and anodic half reaction to a lesser extent. The adsorption of the purines on the metal surface was found to be exothermic and spontaneous. Deviation of the adsorption characteristics of the studied purines from the Langmuir adsorption model was compensated by the fitness of Flory Huggins and El Awardy et al. adsorption models. Quantum chemical studies revealed that the experimental inhibition efficiencies of the studied purines are functions of some quantum chemical parameters including total energy of the molecules (TE), energy gap (E L-H), electronic energy of the molecule (EE), dipole moment and core-core repulsion energy (CCR). Fukui functions analysis through DFT and MP2 theories indicated slight complications and unphysical results. However, results obtained from calculated Huckel charges, molecular orbital and interaction energies, the adsorption of the inhibitors proceeded through the imine nitrogen (N5) in GU, emanine nitrogen (N7) in AD and the pyridine nitrogen (N5) in HPY.

  12. Vibrational relaxation of matrix-isolated CH3F and HCl

    International Nuclear Information System (INIS)

    Young, L.

    1981-08-01

    Kinetic and spectroscopic studies have been performed on CH 3 F and HCl as a function of host matrix and temperature. Temporally and spectrally resolved infrared fluorescence was used to monitor the populations of both the initially excited state and the lower lying levels which participate in the relaxation process. For CH 3 F, relaxation from any of the levels near 3.5 μ, i.e. the CH stretching fundamentals or bend overtones, occurs via rapid ( 3 with subsequent relaxation of the ν 3 (CF stretch) manifold. Lifetimes of 2ν 3 and ν 3 were determined through overtone, ΔV = 2, and fundamental fluorescence. These lifetimes show a dramatic dependence on host lattice, an increase of two orders of magnitude in going from Xe and Ar matrices. Lifetimes depend only weakly on temperature. The relaxation of 2ν 3 and ν 3 is consistent with a model in which production of a highly rotationally excited guest via collisions with the repulsive wall of the host is the rate limiting step. For HCl, lifetimes of v = 1,2,3 have been determined. In all hosts, the relaxation is non-radiative. For a given vibrational state, v, the relaxation rate increases in the series k(Ar) < k(Kr) < k(Xe). The dependence of the relaxation rate; on v is superlinear in all matrices, the deviation from linearity increasng in the order Ar < Kr < Xe. The relaxation rates become more strongly temperature dependent with increasing vibrational excitation. The results are consistent with a mechanism in which complex formation introduces the anisotropy necessary to induce a near resonant V → R transition in the rate limiting step

  13. Comparison of Anti BPH capsule (herbal) and Terazosin HCl in the treatment of benign prostate hyperplasia.

    Science.gov (United States)

    Nadeem, Hafiz Mohammad Rashid; Mohiuddin, Ejaz; UdDin, Shahab; Daniyal, Muhammad; Usmanghani, Khan

    2017-01-01

    Benign prostatic hyperplasia (BPH) is a disease of senile age, usually occurring> 60 years of age. BPH is a disease that involves cell proliferation of the prostate. Pathological hyperplasia affects the elements of the glandular and connective tissue of the prostate. This study is designed to scrutinize the efficacy and tolerability of herbal drug Anti BPH capsule for the management of benign prostate hyperplasia (BPH), in this study we select the 100 patients in which 50 received the Anti BPH capsule and 50 received the Terazosin HCl. We use the American Urological Association BPH Symptom Score Index Questionnaire to measure the quality of life of the patients. We compare the before treatment and after treatment results for each symptom. We record the following symptoms, incomplete emptying of bladder, Frequency, Intermittency, Urgency, Weak stream, Straining, Nocturia and weight of prostate gland by USG. We compare the both drug by using paired sample t-test. The level of significance of incomplete emptying of bladder before treatment and after treatment is 0.013 in test group and 0.032 in control group. Similarly the level of significance of Frequency before treatment and after treatment in test groups in, intermittency, Urgency, Weak stream, staining, Nocturia and mean weight of prostate gland are 0.007, 0.015, 0.044, 0.012, 0.017, 0.004 and 0.020; where as in control group afford as 0.031, 0.044, 0.044, 0.032, 0.024, 0.009 and 0.035 respectively. The herbal drug Anti BPH capsule is more effective in the treatment of BPH than Allopathic medicine Terazosin HCl.

  14. Hydrolysis of ferric chloride in solution

    International Nuclear Information System (INIS)

    Lussiez, G.; Beckstead, L.

    1996-11-01

    The Detox trademark process uses concentrated ferric chloride and small amounts of catalysts to oxidize organic compounds. It is under consideration for oxidizing transuranic organic wastes. Although the solution is reused extensively, at some point it will reach the acceptable limit of radioactivity or maximum solubility of the radioisotopes. This solution could be cemented, but the volume would be increased substantially because of the poor compatibility of chlorides and cement. A process has been developed that recovers the chloride ions as HCl and either minimizes the volume of radioactive waste or permits recycling of the radioactive chlorides. The process involves a two-step hydrolysis at atmospheric pressure, or preferably under a slight vacuum, and relatively low temperature, about 200 degrees C. During the first step of the process, hydrolysis occurs according to the reaction below: FeCl 3 liquid + H 2 O → FeOCl solid + 2 HCl gas During the second step, the hot, solid, iron oxychloride is sprayed with water or placed in contact with steam, and hydrolysis proceeds to the iron oxide according to the following reaction: 2 FeOCl solid + H 2 O → Fe 2 O 3 solid + 2 HCl gas . The iron oxide, which contains radioisotopes, can then be disposed of by cementation or encapsulation. Alternately, these chlorides can be washed off of the solids and can then either be recycled or disposed of in some other way

  15. High-throughput micro-plate HCL-vanillin assay for screening tannin content in sorghum grain

    Science.gov (United States)

    Sorghum contains tannin which is a phenolic compound that offers health promoting antioxidant capacity. The HCl-vanillin assay is a common and time consuming method for determining tannin content, but is not efficient for screening large sample sets as seen in association mapping panels or breeding ...

  16. Oral Ezatiostat HCl (TLK199) and Myelodysplastic syndrome: a case report of sustained hematologic response following an abbreviated exposure.

    Science.gov (United States)

    Quddus, Fahd; Clima, Jessica; Seedham, Helen; Sajjad, Ghulam; Galili, Naomi; Raza, Azra

    2010-04-23

    Treatment options for patients with lower risk non-del(5q) myelodysplastic syndromes (MDS) who fail erythroid stimulating agents are restricted to one of the hypomethylating drugs with an expected response rate of approximately 50%. Ezatiostat HCl, an agent with the potential for producing multi-lineage responses in this population is currently in clinical investigation phase. This case report describes a 77 year old male who received less than two cycles of therapy with ezatiostat HCl which had to be aborted due to intolerable side effects, but which produced a sustained normalization of all three blood counts. This trilineage response has now lasted for more than a year. Interestingly, the patient began with a del(5q) abnormality and responded briefly to lenalidomide. Upon relapse of the anemia, a bone marrow showed the disappearance of the del(5q) but the appearance of a new clonal abnormality t(2;3). Given that the patient had a complete cytogenetic response to a truncated exposure to lenalidomide followed by a trilineage response to an even briefer course of ezatiostat HCl suggests a potential role for ezatiostat HCl in del(5q) patients who relapse following lenalidomide.

  17. TEA CO2 laser-induced reaction of CH3NO2 with CF2HCl: A ...

    Indian Academy of Sciences (India)

    Unknown

    and CH3NO2 molecules as well as UV absorption of CF2 radicals are carried out to elucidate ... nitromethane and H2 under high fluence conditions 10, bright visible ... CF2HCl was monitored by gas chromatography and FTIR spectrometry.

  18. Synthesis of benzyl chlorides and cycloveratrylene macrocycles using benzylic alcohols under homogeneous catalysis by HCl/dioxane

    Directory of Open Access Journals (Sweden)

    Yolanda Marina Vargas-Rodríguez

    2012-01-01

    Full Text Available The synthesis of benzyl chlorides, cyclic derivatives cyclotriveratrylene and cyclotripiperotrylene were carried out in using the HCl/dioxane system as a catalyst. The reaction proceeded with high selectivity and is sensitive to the number of alkyl and methoxy substituent on the aromatic ring.

  19. Acetone enhances the direct analysis of total condensed tannins in plant tissues by the butanol-HCl-iron assay

    Science.gov (United States)

    The butanol-HCl spectrophotometric assay is widely used to quantify extractable and insoluble forms of condensed tannin (CT, syn. proanthocyanidin) in foods, feeds, and foliage of herbaceous and woody plants. However, this method underestimates total CT content when applied directly to plant materia...

  20. 40 CFR 266.107 - Standards to control hydrogen chloride (HCl) and chlorine gas (Cl2) emissions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Standards to control hydrogen chloride... WASTES AND SPECIFIC TYPES OF HAZARDOUS WASTE MANAGEMENT FACILITIES Hazardous Waste Burned in Boilers and Industrial Furnaces § 266.107 Standards to control hydrogen chloride (HCl) and chlorine gas (Cl2) emissions...

  1. 76 FR 41250 - Formetanate HCl and Acephate; Notice of Receipt of Requests to Voluntarily Amend Registrations To...

    Science.gov (United States)

    2011-07-13

    ... registrations to delete uses. The requests would delete formetanate HCl use in or on apple, pear and peach...: Office of Pesticide Programs (OPP) Regulatory Public Docket (7502P), Environmental Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-0001. Delivery: OPP Regulatory Public Docket (7502P...

  2. Simulation studies of the influence of HCl absorption on the performance of a wet flue gas desulphurisation pilot plant

    DEFF Research Database (Denmark)

    Kiil, Søren; Nygaard, Helle; Johnsson, Jan Erik

    2002-01-01

    The mathematical model of Kiil et al, (Ind. Eng, Chem. Res. 37 (1998) 2792) for a wet flue gas desulphurisation (FGD) pilot plant was extended to include the simultaneous absorption of HCl. In contrast to earlier models for wet FGD plants, the inclusion of population balance equations...

  3. HCl Flow-Induced Phase Change of α-, β-, and ε-Ga2O3 Films Grown by MOCVD

    KAUST Repository

    Sun, Haiding

    2018-03-06

    Precise control of the heteroepitaxy on a low-cost foreign substrate is often the key to drive the success of fabricating semiconductor devices in scale when a large low-cost native substrate is not available. Here, we successfully synthesized three different phases of Ga2O3 (α, β, and ε) films on c-plane sapphire by only tuning the flow rate of HCl along with other precursors in an MOCVD reactor. A 3-fold increase in the growth rate of pure β-Ga2O3 was achieved by introducing only 5 sccm of HCl flow. With continuously increased HCl flow, a mixture of β- and ε-Ga2O3 was observed, until the Ga2O3 film transformed completely to a pure ε-Ga2O3 with a smooth surface and the highest growth rate (∼1 μm/h) at a flow rate of 30 sccm. At 60 sccm, we found that the film tended to have a mixture of α- and ε-Ga2O3 with a dominant α-Ga2O3, while the growth rate dropped significantly (∼0.4 μm/h). The film became rough as a result of the mixture phases since the growth rate of ε-Ga2O3 is much higher than that of α-Ga2O3. In this HCl-enhanced MOCVD mode, the Cl impurity concentration was almost identical among the investigated samples. On the basis of our density functional theory calculation, we found that the relative energy between β-, ε-, and α-Ga2O3 became smaller, thus inducing the phase change by increasing the HCl flow in the reactor. Thus, it is plausible that the HCl acted as a catalyst during the phase transformation process. Furthermore, we revealed the microstructure and the epitaxial relationship between Ga2O3 with different phases and the c-plane sapphire substrates. Our HCl-enhanced MOCVD approach paves the way to achieving highly controllable heteroepitaxy of Ga2O3 films with different phases for device applications.

  4. Laboratory study on the high-temperature capture of HCl gas by dry-injection of calcium-based sorbents.

    Science.gov (United States)

    Shemwell, B; Levendis, Y A; Simons, G A

    2001-01-01

    This is a laboratory study on the reduction of combustion-generated hydrochloric acid (HCl) emissions by in-furnace dry-injection of calcium-based sorbents. HCl is a hazardous gaseous pollutant emitted in significant quantities by municipal and hazardous waste incinerators, coal-fired power plants, and other industrial furnaces. Experiments were conducted in a laboratory furnace at gas temperatures of 600-1000 degrees C. HCl gas diluted with N2, and sorbent powders fluidized in a stream of air were introduced into the furnace concurrently. Chlorination of the sorbents occurred in the hot zone of the furnace at gas residence times approximately 1 s. The sorbents chosen for these experiments were calcium formate (CF), calcium magnesium acetate (CMA), calcium propionate (CP), calcium oxide (CX), and calcium carbonate (CC). Upon release of organic volatiles, sorbents calcine to CaO at approximately 700 degrees C, and react with the HCl according to the reaction CaO + 2HCl CaCl2 + H2O. At the lowest temperature case examined herein, 600 degrees C, direct reaction of HCl with CaCO3 may also be expected. The effectiveness of the sorbents to capture HCl was interpreted using the "pore tree" mathematical model for heterogeneous diffusion reactions. Results show that the thin-walled, highly porous cenospheres formed from the pyrolysis and calcination of CF, CMA, and CP exhibited high relative calcium utilization at the upper temperatures of this study. Relative utilizations under these conditions reached 80%. The less costly low-porosity sorbents, calcium carbonate and calcium oxide also performed well. Calcium carbonate reached a relative utilization of 54% in the mid-temperature range, while the calcium oxide reached an 80% relative utilization at the lowest temperature examined. The data matched theoretical predictions of sorbent utilization using the mathematical model, with activation energy and pre-exponential factors for the calcination reaction of 17,000 K and 300

  5. A comparative study on Benzydamine HCL 0.5% and Acetaminophen Codeine in pain reduction following periodontal surgery

    Directory of Open Access Journals (Sweden)

    Khoshkhoonejad AA.

    2004-07-01

    Full Text Available Statement of Problem: Systemic analgesics are frequently prescribed for pain reduction following periodontal surgery. This type of treatment, however, brings about some disadvantages due to its late effect and inherent side effects. Benzydamine hydrochloride mouth wash is a non steroidal anti-inflammatory drug with local anaesthetic properties. Side effects of benzydamine are minor such as tissue numbness, burning and stinging. It brings relief to pain and inflammation rapidly. Purpose: The goal of this study was to compare benzydamine HCL 0.15% and Acetaminophen codeine as analgesics following periodontal surgery. Materials and Methods: This clinical study was performed on 18 patients referred to periodontics Department, Faculty of Dentistry, Tehran University of Medical Sciences. All patients were affected with chronic mild or moderate periodontitis and required surgery at least at two oral sites with similar lesions. Each patient received benzdamine HCL after first surgery and Acetaminophen codein following second operation. Pain reduction was evaluated by Visual Analog Scale (VAS. Data were analyzed with Wilcoxon-Signed and Mann-Whitney non-parametric tests. Results: Analgesic effect of Acetaminophene codeine was significantly more than that of benzydamine HCL following Reriodontal surgery (P=0.008. No significant difference was found between analgesic effects of Acetaminophene codeine and benzydamine HCL in patients with chronic mild periodontitis (P=0.9, and in cases that osteoplasty (P=0-31 or no osseous surgery (P=0.18 were performed. Conclusion: In cases with mild post-operative pain following periodontal surgery, Benzydamine HCL and be prescribed as an analgesic. However, in other cases this mouth wash should be prescribed along with Acetaminophene codein to reduce systemic drugs consumption.

  6. Randomized control trial of benzydamine HCl versus sodium bicarbonate for prophylaxis of concurrent chemoradiation-induced oral mucositis.

    Science.gov (United States)

    Chitapanarux, Imjai; Tungkasamit, Tharatorn; Petsuksiri, Janjira; Kannarunimit, Danita; Katanyoo, Kanyarat; Chakkabat, Chakkapong; Setakornnukul, Jiraporn; Wongsrita, Somying; Jirawatwarakul, Naruemon; Lertbusayanukul, Chawalit; Sripan, Patumrat; Traisathit, Patrinee

    2018-03-01

    The purpose of the study is to compare the efficacy of benzydamine HCl with sodium bicarbonate in the prevention of concurrent chemoradiation-induced oral mucositis in head and neck cancer patients. Sixty locally advanced head and neck cancer patients treated with high-dose radiotherapy concurrently with platinum-based chemotherapy were randomly assigned to receive either benzydamine HCl or sodium bicarbonate from the first day of treatment to 2 weeks after the completion of treatment. The total score for mucositis, based on the Oral Mucositis Assessment Scale (OMAS), was used for the assessment, conducted weekly during the treatment period and at the fourth week of the follow-up. Pain score, all prescribed medications, and tube feeding needs were also recorded and compared. The median of total OMAS score was statistically significant lower in patients who received benzydamine HCl during concurrent chemo-radiotherapy (CCRT) than in those who received sodium bicarbonate, (p value < 0.001). There was no difference in median pain score, (p value = 0.52). Nineteen percent of patients in sodium bicarbonate arm needed oral antifungal agents whereas none in the benzydamine HCl arm required such medications, (p value = 0.06). Tube feeding needs and the compliance of CCRT were not different between the two study arms. For patients undergoing high-dose radiotherapy concurrently with platinum-based chemotherapy, using benzydamine HCl mouthwash as a preventive approach was superior to basic oral care using sodium bicarbonate mouthwash in terms of reducing the severity of oral mucositis and encouraging trend for the less need of oral antifungal drugs.

  7. Corrosion resistance of API 5L grade B steel with taro leaf (Colocasia esculenta) addition as corrosion inhibitor in HCl 0.1 M

    Science.gov (United States)

    Lestari, Yulinda; Priyotomo, Gadang

    2018-05-01

    Taro leaf (Colocasia esculenta) has the potential to be used as a corrosion inhibitor because it has a substance called polyphenol that binds to the hydroxyl group and essential amino acids. Taro leaf extract is taken by maceration method. In this study, the specimen was steel API 5L grade B that would measured the corosivity in 0.1 M HCl solution + taro leaf extract with a specific concentration (in ppm). Tests conducted by FTIR method taro leaves, potentiodynamic polarization (Tafel) and Electrochemical Impedance Spectroscopy (EIS). Based on the results revealed that there is a phenolic group in taro leaves, which has polyphenol content 0.053 % (mg/100 mg). The optimum composition of taro leaf extract is 4000 ppm which generate corrosion rate value of 30.22 mpy and efficiency inhibitor performance of 72.7 %. In this study, the Kads value of taro leaf extract ranged from 0.885 to greater than Kads value of ginger extract in hydrochloric acid solution. The high Kads values indicate a more efficient process of adsorption and better value of inhibition efficiency.

  8. Changes in expression of cytokines in polyhexamethylene guanidine-induced lung fibrosis in mice: Comparison of bleomycin-induced lung fibrosis.

    Science.gov (United States)

    Kim, Min-Seok; Kim, Sung-Hwan; Jeon, Doin; Kim, Hyeon-Young; Lee, Kyuhong

    2018-01-15

    Inhalation of polyhexamethylene guanidine (PHMG) causes irreversible pulmonary injury, such as pulmonary fibrosis. However, the mechanism underlying PHMG-induced lung injury is unclear. In this study, we compared the difference in time-dependent lung injury between PHMG- and bleomycin (BLM)-treated mice and determined cytokines involved in inducing lung injury by performing cytokine antibody array analysis. Mice were treated once with 1.8mg/kg BLM or 1.2mg/kg PHMG through intratracheal instillation and were sacrificed on days 7 and 28. Bronchoalveolar lavage fluid (BALF) analysis showed that the number of neutrophils was significantly higher in PHMG-treated mice than in BLM-treated mice on day 7. Histopathological analysis showed inflammatory cell infiltration and fibrosis mainly in the terminal bronchioles and alveoli in the lungs of PHMG- and BLM-treated mice. However, continuous macrophage infiltration in the alveolar space and bronchioloalveolar epithelial hyperplasia (BEH) were only observed in PHMG-treated mice. Cytokine antibody array analysis showed that 15 and eight cytokines were upregulated in PHMG- and BLM-treated mice, respectively, on day 7. On day 28, 13 and five cytokines were upregulated in PHMG and BLM-treated mice, respectively. In addition, the expressed cytokines between days 7 and 28 in BLM-treated mice were clearly different, but were similar in PHMG-treated mice. Consequently, between PHMG- and BLM-treated mice, we observed differences in the expression patterns and types of cytokines. These differences are considered to be a result of the inflammatory processes induced by both substances, which may mainly involve macrophage infiltration. Therefore, continuous induction of the inflammatory response by PHMG may play an important role in the development of pulmonary fibrosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. The role of NF-κB signaling pathway in polyhexamethylene guanidine phosphate induced inflammatory response in mouse macrophage RAW264.7 cells.

    Science.gov (United States)

    Kim, Ha Ryong; Shin, Da Young; Chung, Kyu Hyuck

    2015-03-04

    Polyhexamethylene guanidine (PHMG) phosphate is a competitive disinfectant with strong antibacterial activity. However, epidemiologists revealed that inhaled PHMG-phosphate may increase the risk of pulmonary fibrosis associated with inflammation, resulting in the deaths of many people, including infants and pregnant women. In addition, in vitro and in vivo studies reported the inflammatory effects of PHMG-phosphate. Therefore, the aim of the present study was to clarify the inflammatory effects and its mechanism induced by PHMG-phosphate in murine RAW264.7 macrophages. Cell viability, inflammatory cytokine secretion, nuclear factor kappa B (NF-κB) activation, and reactive oxygen species (ROS) generation were investigated in macrophages exposed to PHMG-phosphate. PHMG-phosphate induced dose-dependent cytotoxicity, with LC50 values of 11.15-0.99mg/ml at 6 and 24h, respectively. PHMG-phosphate induced pro-inflammatory cytokines including IL-1β, IL-6, and IL-8. In particular, IL-8 expression was completely inhibited by the NF-κB inhibitor BAY11-7082. In addition, PHMG-phosphate decreased IκB-α protein expression and increased NF-κB-mediated luciferase activity, which was diminished by N-acetyl-l-cystein. However, abundant amounts of ROS were generated in the presence of PHMG-phosphate at high concentrations with a cytotoxic effect. Our results demonstrated that PHMG-phosphate triggered the activation of NF-κB signaling pathway by modulating the degradation of IκB-α. Furthermore, the NF-κB signaling pathway plays a critical role in the inflammatory responses induced by PHMG-phosphate. We assumed that ROS generated by PHMG-phosphate were associated with inflammatory responses as secondary mechanism. In conclusion, we suggest that PHMG-phosphate induces inflammatory responses via NF-κB signaling pathway. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. Kinetics of the CH3 + HCl/DCl → CH4/CH3D + Cl and CD3 + HCl/DCl → CD3H/CD4 + Cl reactions: An experimental H atom tunneling investigation

    International Nuclear Information System (INIS)

    Eskola, Arkke J.; Seetula, Jorma A.; Timonen, Raimo S.

    2006-01-01

    The kinetics of the radical reactions of CH 3 with HCl or DCl and CD 3 with HCl or DCl have been investigated in a temperature controlled tubular reactor coupled to a photoionization mass spectrometer. The CH 3 (or CD 3 ) radical, R, was produced homogeneously in the reactor by a pulsed 193 nm exciplex laser photolysis of CH 3 COCH 3 (or CD 3 COCD 3 ). The decay of CH 3 /CD 3 was monitored as a function of HCl/DCl concentration under pseudo-first-order conditions to determine the rate constants as a function of temperature, typically from 188 to 500 K. The rate constants of the CH 3 and CD 3 reactions with HCl had strong non-Arrhenius behavior at low temperatures. The rate constants were fitted to a modified Arrhenius expression k = QA exp (-E a /RT) (error limits stated are 1σ + Students t values, units in cm 3 molecule -1 s -1 ): k(CH 3 + HCl) = [1.004 + 85.64 exp (-0.02438 x T/K)] x (3.3 ± 1.3) x 10 -13 exp [-(4.8 ± 0.6) kJ mol -1 /RT] and k(CD 3 + HCl) = [1.002 + 73.31 exp (-0.02505 x T/K)] x (2.7 ± 1.2) x 10 -13 exp [-(3.5 ± 0.5) kJ mol -1 /RT]. The radical reactions with DCl were studied separately over a wide ranges of temperatures and in these temperature ranges the rate constants determined were fitted to a conventional Arrhenius expression k = A exp (-E a /RT) (error limits stated are 1σ + Students t values, units in cm 3 molecule -1 s -1 ): k(CH 3 + DCl) = (2.4 ± 1.6) x 10 -13 exp [-(7.8 ± 1.4) kJ mol -1 /RT] and k(CD 3 + DCl) = (1.2 ± 0.4) x 10 -13 exp [-(5.2 ± 0.2) kJ mol -1 /RT] cm 3 molecule -1 s -1 . Curvature in the Arrhenius plots of the H-atom abstraction reactions at low temperatures was analyzed by considering H-atom tunneling through the reaction barrier and primary kinetic isotope effect. Contribution of tunneling in it was concluded to be negligible. In addition, secondary isotope effect was measured

  11. Preparation and characterization of polymeric and lipid nanoparticles of pilocarpine HCl for ocular application.

    Science.gov (United States)

    Lütfi, Genç; Müzeyyen, Demirel

    2013-01-01

    Pilocarpine is used topically in the treatment of glaucoma. Various studies were performed to improve the bioavailability and prolong the residence time of drugs in ocular drug delivery. Drug loaded polymeric and lipid nanoparticles offer several favourable biological properties, such as biodegradability, nontoxicity, biocompatibility and mucoadhesiveness. Therefore, preparing positively-charged pilocarpine HCl-loaded polymeric and lipid nanoparticles was the purpose of this study. Nanoparticles were prepared by quasi-emulsion solvent evaporation technique. The non-biodegradable positively-charged polymer Eudragit(®) RS 100 and semi-solid lipid excipient Gelucire(®) 44/14 were used as a vehicle, the cationic lipid octadecylamine was used as a cationic agent. The formulations were evaluated in terms of particle size, size distribution, zeta potential measurement, thermal behavior (Differential Scanning Calorimetry DSC), entrapment efficacy and pH. Characterizations of nanoparticles were analyzed during the storage period of 6 months for stability tests. Polymeric and lipid nanoparticles could be prepared successfully promising their use for ophthalmic delivery.

  12. CO- and HCl-free synthesis of acid chlorides from unsaturated hydrocarbons via shuttle catalysis

    Science.gov (United States)

    Fang, Xianjie; Cacherat, Bastien; Morandi, Bill

    2017-11-01

    The synthesis of carboxylic acid derivatives from unsaturated hydrocarbons is an important process for the preparation of polymers, pharmaceuticals, cosmetics and agrochemicals. Despite its industrial relevance, the traditional Reppe-type carbonylation reaction using pressurized CO is of limited applicability to laboratory-scale synthesis because of: (1) the safety hazards associated with the use of CO, (2) the need for special equipment to handle pressurized gas, (3) the low reactivity of several relevant nucleophiles and (4) the necessity to employ different, often tailor-made, catalytic systems for each nucleophile. Herein we demonstrate that a shuttle-catalysis approach enables a CO- and HCl-free transfer process between an inexpensive reagent, butyryl chloride, and a wide range of unsaturated substrates to access the corresponding acid chlorides in good yields. This new transformation provides access to a broad range of carbonyl-containing products through the in situ transformation of the reactive acid chloride intermediate. In a broader context, this work demonstrates that isodesmic shuttle-catalysis reactions can unlock elusive catalytic reactions.

  13. Non-Markovian near-infrared Q branch of HCl diluted in liquid Ar.

    Science.gov (United States)

    Padilla, Antonio; Pérez, Justo

    2013-08-28

    By using a non-Markovian spectral theory based in the Kubo cumulant expansion technique, we have qualitatively studied the infrared Q branch observed in the fundamental absorption band of HCl diluted in liquid Ar. The statistical parameters of the anisotropic interaction present in this spectral theory were calculated by means of molecular dynamics techniques, and found that the values of the anisotropic correlation times are significantly greater (by a factor of two) than those previously obtained by fitting procedures or microscopic cell models. This fact is decisive for the observation in the theoretical spectral band of a central Q resonance which is absent in the abundant previous researches carried out with the usual theories based in Kubo cumulant expansion techniques. Although the theory used in this work only allows a qualitative study of the Q branch, we can employ it to study the unknown characteristics of the Q resonance which are difficult to obtain with the quantum simulation techniques recently developed. For example, in this study we have found that the Q branch is basically a non-Markovian (or memory) effect produced by the spectral line interferences, where the PR interferential profile basically determines the Q branch spectral shape. Furthermore, we have found that the Q resonance is principally generated by the first rotational states of the first two vibrational levels, those more affected by the action of the dissolvent.

  14. Interpretation of IR and Raman spectra of dopamine neurotransmitter and effect of hydrogen bond in HCl

    Science.gov (United States)

    Yadav, T.; Mukherjee, V.

    2018-05-01

    The potential energy scanning with respect to the different dihedral angles were performed to search possible numbers of dopamine (neutral) conformers and further, fifteen conformers of dopamine were identified on the basis of energy minima. Vibrational frequencies were calculated for all the conformers of dopamine. Density functional theory was employed to carry out all the computations. The exchange correlation functional B3LYP and the basis set 6-31++G(d,p) were included in DFT calculation. The FTIR and FT-Raman spectra of dopamine hydrochloride were also recorded in the spectral region 400-4000 cm-1 and 50-4000 cm-1 respectively. The normal coordinate analysis was also performed to scale DFT calculated force constants and to calculate potential energy distributions. The detailed vibrational spectral analysis and the assignments of the bands, done on the best-fit basis comparison of the experimentally obtained and theoretically calculated IR and Raman spectra, match quite well indicating DFT calculations as very accurate source of normal mode assignments. The interaction of the most stable conformer of dopamine with HCl was also studied to know the effect of hydrogen bond on its geometry and dynamics. The stability of the dopamine in isolated and protonated forms arising from hyperconjugative interactions was also analyzed by natural bond orbital analysis.

  15. A review of pioglitazone HCL and glimepiride in the treatment of type 2 diabetes.

    Science.gov (United States)

    Dorkhan, Mozhgan; Frid, Anders

    2007-01-01

    Type 2 diabetes (T2D) is a progressive disorder with a consistent and steady increase in glycosylated hemoglobin (HbA1c) over time associated with enhanced risk of micro- and macrovascular complications and a substantial reduction in life expectancy. There are three major pathophysiologic abnormalities associated with T2D: impaired insulin secretion, excessive hepatic glucose output, and insulin resistance in skeletal muscle, liver, and adipose tissue. These defects have been treated in clinical praxis by use of oral insulin secretagogues (sulfonylureas/ glinides) or insulin, biguanides, and thiazolidinediones (TZDs) respectively. Pioglitazone HCL is an insulin sensitizer in the TZD family and glimepiride is an insulin secretagogue in the SU family. This article reviews mechanisms of action and clinical data behind the use of these two commonly used oral hypoglycemic agents with documented efficacy and good safety profile of once-daily administration, alone or in combination with insulin or metformin, in the management of T2D in terms of glycemic and non-glycemic effects, tolerability and side effects, and impact on vascular health.

  16. A review of pioglitazone HCL and glimepiride in the treatment of type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Mozhgan Dorkhan

    2007-11-01

    Full Text Available Mozhgan Dorkhan, Anders FridDepartment of Clinical Sciences, Division of Diabetes and Endocrinology, Lund University, Malmö University Hospital, SwedenAbstract: Type 2 diabetes (T2D is a progressive disorder with a consistent and steady increase in glycosylated hemoglobin (HbA1c over time associated with enhanced risk of micro- and macrovascular complications and a substantial reduction in life expectancy. There are three major pathophysiologic abnormalities associated with T2D: impaired insulin secretion, excessive hepatic glucose output, and insulin resistance in skeletal muscle, liver, and adipose tissue. These defects have been treated in clinical praxis by use of oral insulin secretagogues (sulfonylureas/glinides or insulin, biguanides, and thiazolidinediones (TZDs respectively. Pioglitazone HCL is an insulin sensitizer in the TZD family and glimepiride is an insulin secretagogue in the SU family. This article reviews mechanisms of action and clinical data behind the use of these two commonly used oral hypoglycemic agents with documented efficacy and good safety profile of once-daily administration, alone or in combination with insulin or metformin, in the management of T2D in terms of glycemic and non-glycemic effects, tolerability and side effects, and impact on vascular health.Keywords: pioglitazone, glimepiride, type 2 diabetes, thiazolidinediones, sulfonylureas

  17. Laser Desorption of Tryptophan from Tryptophan-HCl Salt on a Graphite Substrate

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Hae Jun; Kim, Jeong Jin; Kang, Hyuk [Ajou University, Suwon (Korea, Republic of)

    2016-03-15

    Laser spectroscopy of biological molecules in the gas phase has been pioneered by Levy and coworkers when they first produced a supersonic molecular beam of tryptophan (Trp) and obtained its electronic spectrum. They were able to obtain enough vapor pressure needed for spectroscopy by heating a powder sample of Trp, although a special thermal spray was used to minimize fragmentation during heating. Many amine compounds, including biomolecules like amino acids and peptides, are usually available only as HCl salt form in order to prevent oxidation in air. Chemical processing is required to recover a neutral amine compound from its salt, thus limiting the applicability of laser-desorption spectroscopy of biomolecules. The experimental setup is a standard molecular beam machine composed of a pulsed valve with a laser-desorption module in a vacuum chamber, a second buffer chamber, a skimmer that separates the first and the second chambers, and a third vacuum chamber that is a time-of-flight mass spectrometer (TOF MS)

  18. Recommendation for KIT-formulation of radioiodinated [{sup *}I] meta-iodo benzyl guanidine (M*IBG). Vol. 3.

    Energy Technology Data Exchange (ETDEWEB)

    El-shaboury, G; El-Kolaly, M T; Raieh, M; El-Bayoumy, S [Radioisotope Production and Labelled Compounds Department, Cairo (Egypt); Zakareia, N [Chemistry of Nuclear Fuel Department, Hot laboratories Center, Atomic Energy Authority, Cairo (Egypt)

    1996-03-01

    A recommended simple technique for preparation of radioiodinated [{sup *}I{sup -}] meta - iodobenzylguanidine (M{sup *} IBG) is presented. The technique is based on a schematic procedure for the synthesis of inactive M IBG using meta -iodo benzoic as substrate, results into a chemical yield of 80% as pure as M IBG 0.5 substrate, then recrystallized from water - ethyl alcohol as crystalline powder of M.P. 165 Degree C - 167 degree C. The radioiodination process is performed through an isotropic exchange reaction between the inactive M IBG and radioiodine as iodine ion ({sup *}I{sup -}) in 0.2 M acetate buffer pH 4.2 - 4.25 at 100 degree C within 30 min in the presence of metal as exchange catalyst. Following these processes, the reaction solution is allowed for purification by passing it through an AgCl - impregnated filter to remove the unreacted radioiodine as Ag{sup *}I (5%). According of these results and reaction conditions it was possible to develop a technology for the radiopharmaceutical production of radioiodinated M{sup *} IBG using the currently used short - lived radioiodine nuclides by a simple kit like - type technique, where the radiochemical yield % is 95 - 99% as pure as M{sup *} IBG. 5 figs., 3 tabs.

  19. Recommendation for KIT-formulation of radioiodinated [*I] meta-iodo benzyl guanidine (M*IBG). Vol. 3

    International Nuclear Information System (INIS)

    El-shaboury, G.; El-Kolaly, M.T.; Raieh, M.; El-Bayoumy, S.; Zakareia, N.

    1996-01-01

    A recommended simple technique for preparation of radioiodinated [ * I - ] meta - iodobenzylguanidine (M * IBG) is presented. The technique is based on a schematic procedure for the synthesis of inactive M IBG using meta -iodo benzoic as substrate, results into a chemical yield of 80% as pure as M IBG 0.5 substrate, then recrystallized from water - ethyl alcohol as crystalline powder of M.P. 165 Degree C - 167 degree C. The radioiodination process is performed through an isotropic exchange reaction between the inactive M IBG and radioiodine as iodine ion ( * I - ) in 0.2 M acetate buffer pH 4.2 - 4.25 at 100 degree C within 30 min in the presence of metal as exchange catalyst. Following these processes, the reaction solution is allowed for purification by passing it through an AgCl - impregnated filter to remove the unreacted radioiodine as Ag * I (5%). According of these results and reaction conditions it was possible to develop a technology for the radiopharmaceutical production of radioiodinated M * IBG using the currently used short - lived radioiodine nuclides by a simple kit like - type technique, where the radiochemical yield % is 95 - 99% as pure as M * IBG. 5 figs., 3 tabs

  20. Applicability of the Chinese version of the Hypomania Symptom Checklist (HCL-32 scale for outpatients of psychiatric departments in general hospitals.

    Directory of Open Access Journals (Sweden)

    Xiao Huang

    Full Text Available OBJECTIVES: This study aimed to determine the suitability of the Chinese version of the Hypomania Symptom Checklist (HCL-32 scale for psychiatric department outpatients with mood disorders in Chinese general hospitals, and provide a theoretical basis for the application of the HCL-32 scale. METHODS: Outpatients with mood disorders receiving continuous treatment in the psychiatric medicine department of three top-ranking general hospitals in three cities completed scoring the HCL-32 scale. RESULTS: A total of 1010 patients were recruited. 417 were diagnosed with bipolar disorder (236 for type I and 181 for type II and 593 were depression. Four factors with eigenvalues >1 were considered. Factor 1 with an eigenvalue of 5.5 was labeled "active/cheerful". Factor 2 with an eigenvalue of 2.7 was labeled "adventurous/irritable." The coefficient of internal consistency reliability of the HCL-32 total scale was 0.84, and the coefficients for factors 1 and 2 were 0.84 and 0.88, respectively. With the total score of HCL-32≥14 as positive standard, the sensitivity of HCL-32 was calculated at 69.30% and the specificity was 97.81%. CONCLUSIONS: Results showed that HCL-32 had a preferable reliability and validity and was suitable as auxiliary means for bipolar disorder screening in general hospitals.

  1. Mathematical modeling of the radiation-chemical oxidation of U(IV) in HClO4

    International Nuclear Information System (INIS)

    Vladimirova, M.V.

    1995-01-01

    Mathematical modeling of U(IV) oxidation in 0.5-12 M HClO 4 upon α, γ-radiolysis, based on the proposed scheme of radiation-chemical reactions, has been performed. The rate constants of the U(VI) + HO 2 , U(IV) + HO 2 , U(IV) + ClO 2 , and U(IV) + ClO 2 - reactions have been determined by the comparison of the calculated and experimental kinetic and dose curves and radiation-chemical yields of U(IV) oxidation or U(VI) formation. General equations for uranium (IV) oxidation constants at various HClO 4 concentrations, based on the analysis of the rates of particular radiation-chemical reactions composing oxidation process, have been obtained

  2. The centrifugal sudden distorted wave method for chemical reactions: Application to Cl+HCl → ClH+Cl

    International Nuclear Information System (INIS)

    Amaee, B.; Connor, J.N.L.; Schatz, G.C.

    1987-01-01

    The authors describe a method for calculating cross sections for atom plus diatom reactive collisions based on the centrifugal sudden distorted wave (CSDW) approximation. This method is nearly exact at low energies where reactive cross sections are small. Representative CPU times are given for applications of CSDW method to the Cl + HCl → ClH + Cl reaction using CDC 7600, Cyber 176, Cyber 205, Cray XMP and Cray 2 computers. Calculations show that the product HCl molecule is highly rotationally excited, (receiving 40-50% of the available energy) and that the shape of the product rotational distribution is nearly independent of reagent rotational state. The authors also calculated product differential cross sections and find them to be backward peaked at low energies

  3. Evaluation of Resin Regeneration Using HCl and H2SO4 for the Ion Exchanger of Copper

    International Nuclear Information System (INIS)

    Prayitno; Djoko Sardjono

    2002-01-01

    The experimental investigation on the regeneration of resin using HCl and H 2 SO 4 with its varian concentration of 1; 2.5; 2; 2.5 and 3 N and the stirring time was 5; 10; 15; 20; and 25 minutes. For evaluating their effectiveness on the separation of ion copper in the waste with concentration 500 ppm. Experimentally this investigation is the first step of resin results of regeneration process usage as an alternative resin for the treatment of liquid waste containing especially copper. The experimental resulted by mixing the feed copper waste with resin after regeneration. Therefore it could be concluded that the most effective regeneration was obtained with HCl as the regeneration of concentration 2 N and the stirring time 15 minutes with the percentage of separation used of 85.1 %. (author)

  4. Observed and simulated time evolution of HCl, ClONO2, and HF total columns

    Science.gov (United States)

    Ruhnke, Roland; Geomon, Ndacc Infrared, Modelling Working Group

    2010-05-01

    Institute of Technology (KIT), IMK-IFU, Garmisch-Partenkirchen, Germany, (16) University of Denver, Dept. of Physics and Astronomy, Denver, CO, USA, (17) National Center for Atmospheric Research (NCAR), Boulder, CO, USA, (18) NASA Langley Research Center, Hampton, VA, USA, (19) Karlsruhe Institute of Technology (KIT), Steinbuch Centre for Computing, Karlsruhe, Germany Total column abundances of HCl and ClONO2, the primary components of the stratospheric inorganic chlorine (Cly) budget, and of HF have been retrieved from ground-based, high-resolution infrared solar absorption spectra recorded at 17 sites of the Network for the Detection of Atmospheric Composition Change (NDACC) located at latitudes between 80.05°N and 77.82°S. These data extend over more than 20 years (through 2007) during a period when the growth in atmospheric halogen loading has slowed in response to the Montreal Protocol (and ammendments). These observed time series are interpreted with calculations performed with a 2-D model, the 3-D chemistry-transport models (CTMs) KASIMA and SLIMCAT, and the 3-D chemistry-climate models (CCMs) EMAC and SOCOLv2.0. The observed Cly and in particular HCl column abundances decreases significantely since the end of the nineties at all stations, which is consistent with the observed changes in the halocarbon source gases, with an increasing rate in the last years. In contrast to Cly, the trend values for total column HF at the different stations show a less consistent behaviour pointing to the fact that the time development of the HF columns is peaking. There is a good overall qualitative agreement regarding trends between models and data. With respect to the CTMs the agreement improves if simulation results for measurement days only are used in the trend analysis instead of simulation results for each day.

  5. Enhanced Ungual Permeation of Terbinafine HCl Delivered Through Liposome-Loaded Nail Lacquer Formulation Optimized by QbD Approach.

    Science.gov (United States)

    Shah, Viral H; Jobanputra, Amee

    2018-01-01

    The present investigation focused on developing, optimizing, and evaluating a novel liposome-loaded nail lacquer formulation for increasing the transungual permeation flux of terbinafine HCl for efficient treatment of onychomycosis. A three-factor, three-level, Box-Behnken design was employed for optimizing process and formulation parameters of liposomal formulation. Liposomes were formulated by thin film hydration technique followed by sonication. Drug to lipid ratio, sonication amplitude, and sonication time were screened as independent variables while particle size, PDI, entrapment efficiency, and zeta potential were selected as quality attributes for liposomal formulation. Multiple regression analysis was employed to construct a second-order quadratic polynomial equation and contour plots. Design space (overlay plot) was generated to optimize a liposomal system, with software-suggested levels of independent variables that could be transformed to desired responses. The optimized liposome formulation was characterized and dispersed in nail lacquer which was further evaluated for different parameters. Results depicted that the optimized terbinafine HCl-loaded liposome formulation exhibited particle size of 182 nm, PDI of 0.175, zeta potential of -26.8 mV, and entrapment efficiency of 80%. Transungual permeability flux of terbinafine HCl through liposome-dispersed nail lacquer formulation was observed to be significantly higher in comparison to nail lacquer with a permeation enhancer. The developed formulation was also observed to be as efficient as pure drug dispersion in its antifungal activity. Thus, it was concluded that the developed formulation can serve as an efficient tool for enhancing the permeability of terbinafine HCl across human nail plate thereby improving its therapeutic efficiency.

  6. Effect of n-octanol on the extraction behavior of trace cobalt in TOA-HCl system

    International Nuclear Information System (INIS)

    Mukhopadhyay, Krishnendu; Mandal, Anjana; Mukhopadhyay, Banani; Nayak, Dalia; Lahiri, Susanta

    1997-01-01

    Effect of the presence of n-octanol in the extraction of traces of cobalt in HCl-TOA system was studied. In the extraction, both synergistic and antagonistic effects, depending on the volume of alcohol present, were observed. Extraction behaviour of the element was studied radiometrically using 57,58 Co, produced by α- particle bombardment of cobalt, as radiotracer for the element. (author). 1 fig

  7. Benchmark calculations with correlated molecular wave functions. IX. The weakly bound complexes Ar - H2 and Ar - HCl

    International Nuclear Information System (INIS)

    Woon, D.E.; Peterson, K.A.; Dunning, T.H. Jr.

    1998-01-01

    The interaction of Ar with H 2 and HCl has been studied using Moeller - Plesset perturbation theory (MP2, MP3, MP4) and coupled-cluster [CCSD, CCSD(T)] methods with augmented correlation consistent basis sets. Basis sets as large as triply augmented quadruple zeta quality were used to investigate the convergence trends. Interaction energies were determined using the supermolecule approach with the counterpoise correction to account for basis set superposition error. Comparison with the available empirical potentials finds excellent agreement for both binding energies and transition state. For Ar - H 2 , the estimated complete basis set (CBS) limits for the binding energies of the two equivalent minima and the connecting transition state (TS) are, respectively, 55 and 47cm -1 at the MP4 level and 54 and 46cm -1 at the CCSD(T) level, respectively [the XC(fit) empirical potential of Bissonnette et al. [J. Chem. Phys. 105, 2639 (1996)] yields 56.6 and 47.8cm -1 for H 2 (v=0)]. The estimated CBS limits for the binding energies of the two minima and transition state of Ar - HCl are 185, 155, and 109cm -1 at the MP4 level and 176, 147, and 105cm -1 at the CCSD(T) level, respectively [the H6(4,3,0) empirical potential of Hutson [J. Phys. Chem. 96, 4237 (1992)] yields 176.0, 148.3, and 103.3cm -1 for HCl (v=0)]. Basis sets containing diffuse functions of (dfg) symmetries were found to be essential for accurately modeling these two complexes, which are largely bound by dispersion and induction forces. Highly correlated wave functions were also required for accurate results. This was found to be particularly true for ArHCl, where significant differences in calculated binding energies were observed between MP2, MP4, and CCSD(T). copyright 1998 American Institute of Physics

  8. Evaluation of a Novel, Natural Locust Bean Gum as a Sustained Release and Mucoadhesive Component of Tizanidine Hcl Buccal Tablets

    OpenAIRE

    Harikrishnan.V

    2015-01-01

    Mucoadhesive polymers that bind to the gastric mucin or epithelial cell surface are useful in drug delivery for the purpose of increasing the intimacy and duration of contact of drug with the absorbing membrane. Mainly synthetic polymers are in use for this purpose. Probably the biodegradability of the synthetic polymers are questionable, In the present work mucoadhesive buccal tablets of Tizanidine hydrochloride (TZD HCl) were prepared by using locust bean gum that have better mucoadhesive p...

  9. Enhancement of oral bioavailability of anti-HIV drug rilpivirine HCl through nanosponge formulation.

    Science.gov (United States)

    Zainuddin, Rana; Zaheer, Zahid; Sangshetti, Jaiprakash N; Momin, Mufassir

    2017-12-01

    To synthesize β cyclodextrin nanosponges using a novel and efficient microwave mediated method for enhancing bioavailability of Rilpivirine HCl (RLP). Belonging to BCS class II RLP has pH dependent solubility and poor oral bioavailability. However, a fatty meal enhances its absorption hence the therapy indicates that the dosage form be consumed with a meal. But then it becomes tedious and inconvenient to continue the therapy for years with having to face the associated gastric side effects such as nausea. Microwave synthesizer was used to mediate the poly-condensation reaction between β-cyclodextrin and cross-linker diphenylcarbonate. Critical parameters selected were polymer to cross-linker ratio, Watt power, reaction time and solvent volume. Characterization studies were performed using FTIR, DSC, SEM, 1 H-NMR and PXRD. Molecular modeling was applied to confirm the possibility of drug entrapment. In vitro drug dissolution followed by oral bioavailability studies was performed in Sprawley rats. Samples were analyzed using HPLC. Microwave synthesis yields para-crystalline, porous nanosponges (∼205 nm). Drug entrapment led to enhancement of solubility and a two-fold increase in drug dissolution (P bioavailability was observed in fasted Sprawley rats where C max and AUC 0-∞ increases significantly (C max of NS∼ 586 ± 5.91 ng/mL; plain RLP ∼310 ± 5. 74 ng/mL). The approach offers a comfortable dosing zone for AIDs patients, negating the requirement of consuming the formulation in a fed state due to enhancement in drugs' oral bioavailability.

  10. Ion-Selective Electrodes for the Potentiometric Determination of Pramoxine HCl Using Different Ionophores.

    Science.gov (United States)

    Ramadan, Nesrin K; Merey, Hanan A

    2012-12-01

    Four novel pramoxine HCl (PAM) selective electrodes were investigated with 2-nitrophenyl octylether as a plasticiser in a polymeric matrix of polyvinyl chloride (PVC). Sensor 1 was fabricated using sodium-tetraphenylborate (TPB) as an anionic exchanger without incorporation of an ionophore. Sensor 2 used 2-hydroxy propyl -cyclodextrin as an ionophore, while sensors 3 and 4 were constructed using 4-sulfocalix-6-arene and 4-sulfocalix-8-arene respectively as ionophores. Linear responses of PAM within the concentration ranges of 1.0 × 10-4 to 1.0 × 10-2 mol L-1 and 1.0 × 10-5 to 1.0 × 10-2 mol L-1 were obtained using sensors 1 and 2, respectively and 1.0 × 10-6 to 1.0 × 10-2 mol L-1 were obtained using sensors 3 and 4. Nernstian slopes of 50.4 ± 0.6, 54.3 ± 0.8, 56.3 ± 0.3 and 59.1 ± 0.5 mV/decade over the pH range of 3.0-6.0 were observed. The selectivity coefficients of the developed sensors indicated excellent selectivity for PAM. The utility of 2-hydroxy- propylcyclodextrin (2HP-β-CD) and 4-sulfocalix [6,8] arene (SC 6, 8) as ionophores had a significant influence on increasing the membrane sensitivity and selectivity of sensors 2, 3 and 4 compared to sensor 1. The proposed sensors displayed useful analytical characteristics for the determination of PAM in bulk powder, pharmaceutical formulation, and in biological fluid. Validation of the method showed the suitability of the proposed electrodes for the use in the quality control assessment of the drug. Furthermore, statistical comparison between the results obtained by the proposed method and the official method of the drug was performed and no significant difference was found.

  11. Minocycline HCl microspheres reduce red-complex bacteria in periodontal disease therapy.

    Science.gov (United States)

    Goodson, J Max; Gunsolley, John C; Grossi, Sara G; Bland, Paul S; Otomo-Corgel, Joan; Doherty, Frances; Comiskey, Judy

    2007-08-01

    The objective of this trial was to measure the antimicrobial effects of a minocycline HCl microsphere (MM) local drug-delivery system when used as an adjunct to scaling and root planing (SRP). DNA probe analysis for 40 bacteria was used to evaluate the oral bacteria of 127 subjects with moderate to advanced chronic periodontitis. Subjects were randomly assigned to either SRP alone (N = 65) or MM + SRP (N = 62). The primary endpoints of this study were changes in numbers and proportions of the red-complex bacteria (RCB) and the sum of Porphyromonas gingivalis, Tannerella forsythia (formally T. forsythensis), and Treponema denticola relative to 40 oral bacteria at each test site from baseline to day 30. Numbers of RCB from the five test sites were averaged to provide a value for each subject. MM + SRP reduced the proportion of RCB by 6.49% and the numbers by 9.4 x 10(5). The reduction in RCB proportions and numbers by SRP alone (5.03% and 5.1 x 10(5), respectively) was significantly less. In addition, MM + SRP reduced probing depth by 1.38 mm (compared to 1.01 mm by SRP alone), bleeding on probing was reduced by 25.2% (compared to 13.8% by SRP alone), and a clinical attachment level gain of 1.16 mm (compared to 0.80 mm by SRP alone) was achieved. These observations support the hypothesis that RCBs are responsible for periodontal disease and that local antimicrobial therapy using MM + SRP effectively reduces numbers of RCBs and their proportions to a greater extent than SRP alone.

  12. Spectrophotometric Methods for Simultaneous Determination of Oxytetracycline HCl and Flunixin Meglumine in Their Veterinary Pharmaceutical Formulation

    Directory of Open Access Journals (Sweden)

    Hanan A. Merey

    2017-01-01

    Full Text Available Four precise, accurate, selective, and sensitive UV-spectrophotometric methods were developed and validated for the simultaneous determination of a binary mixture of Oxytetracycline HCl (OXY and Flunixin Meglumine (FLU. The first method, dual wavelength (DW, depends on measuring the difference in absorbance (ΔA 273.4–327 nm for the determination of OXY where FLU is zero while FLU is determined at ΔA 251.7–275.7 nm. The second method, first-derivative spectrophotometric method (1D, depends on measuring the peak amplitude of the first derivative selectively at 377 and 266.7 nm for the determination of OXY and FLU, respectively. The third method, ratio difference method, depends on the difference in amplitudes of the ratio spectra at ΔP 286.5–324.8 nm and ΔP 249.6–286.3 nm for the determination of OXY and FLU, respectively. The fourth method, first derivative of ratio spectra method (1DD, depends on measuring the amplitude peak to peak of the first derivative of ratio spectra at 296.7 to 369 nm and 259.1 to 304.7 nm for the determination of OXY and FLU, respectively. Different factors affecting the applied spectrophotometric methods were studied. The proposed methods were validated according to ICH guidelines. Satisfactory results were obtained for determination of both drugs in laboratory prepared mixture and pharmaceutical dosage form. The developed methods are compared favourably with the official ones.

  13. Shuidouchi (Fermented Soybean Fermented in Different Vessels Attenuates HCl/Ethanol-Induced Gastric Mucosal Injury

    Directory of Open Access Journals (Sweden)

    Huayi Suo

    2015-11-01

    Full Text Available Shuidouchi (Natto is a fermented soy product showing in vivo gastric injury preventive effects. The treatment effects of Shuidouchi fermented in different vessels on HCl/ethanol-induced gastric mucosal injury mice through their antioxidant effect was determined. Shuidouchi contained isoflavones (daidzein and genistein, and GVFS (glass vessel fermented Shuidouchi had the highest isoflavone levels among Shuidouchi samples fermented in different vessels. After treatment with GVFS, the gastric mucosal injury was reduced as compared to the control mice. The gastric secretion volume (0.47 mL and pH of gastric juice (3.1 of GVFS treated gastric mucosal injury mice were close to those of ranitidine-treated mice and normal mice. Shuidouchi could decrease serum motilin (MTL, gastrin (Gas level and increase somatostatin (SS, vasoactive intestinal peptide (VIP level, and GVFS showed the strongest effects. GVFS showed lower IL-6, IL-12, TNF-α and IFN-γ cytokine levels than other vessel fermented Shuidouchi samples, and these levels were higher than those of ranitidine-treated mice and normal mice. GVFS also had higher superoxide dismutase (SOD, nitric oxide (NO and malonaldehyde (MDA contents in gastric tissues than other Shuidouchi samples. Shuidouchi could raise IκB-α, EGF, EGFR, nNOS, eNOS, Mn-SOD, Gu/Zn-SOD, CAT mRNA expressions and reduce NF-κB, COX-2, iNOS expressions as compared to the control mice. GVFS showed the best treatment effects for gastric mucosal injuries, suggesting that glass vessels could be used for Shuidouchi fermentation in functional food manufacturing.

  14. Two-dimensional simulation of the development of an inhomogeneous volume discharge in a Ne/Xe/HCl gas mixture

    International Nuclear Information System (INIS)

    Bychkov, Yu. I.; Yampolskaya, S. A.; Yastremskii, A. G.

    2013-01-01

    The kinetic processes accompanying plasma column formation in an inhomogeneous discharge in a Ne/Xe/HCl gas mixture at a pressure of 4 atm were investigated by using a two-dimensional model. Two cathode spots spaced by 0.7 cm were initiated by distorting the cathode surface at local points, which resulted in an increase in the field strength in the cathode region. Three regimes differing in the charging voltage, electric circuit inductance, and electric field strength at the local cathode points were considered. The spatiotemporal distributions of the discharge current; the electron density; and the densities of excited xenon atoms, HCl(v = 0) molecules in the ground state, and HCl(v > 0) molecules in vibrational levels were calculated. The development of the discharge with increasing the electron density from 10 4 to 10 16 cm −3 was analyzed, and three characteristic stages in the evolution of the current distribution were demonstrated. The width of the plasma column was found to depend on the energy deposited in the discharge. The width of the plasma column was found to decrease in inverse proportion to the deposited energy due to spatiotemporal variations in the rates of electron production and loss. The calculated dependences of the cross-sectional area of the plasma column on the energy deposited in the discharge agree with the experimental results.

  15. High-resolution Measurements of Gas-Phase Hydrogen Chloride (HCl) in the Atmosphere by Cavity Ring Down Spectroscopy

    Science.gov (United States)

    Hoffnagle, John; Chen, Hongbing; Lee, Jim; Rella, Chris; Kim-Hak, David; Winkler, Renato; Markovic, Milos; Veres, Patrick

    2017-04-01

    Halogen radical species, such as chlorine and bromine atoms and their oxides, can greatly affect the chemical composition of the troposphere. Hydrogen chloride is the dominant (gas-phase) contributor to the tropospheric chlorine inventory. Real time in situ observations of HCl can provide an important window into the complex photochemical reaction pathways for chlorine in the atmosphere, including heterogeneous reactions on aerosol surfaces. In this work, we report a novel, commercially-available HCl gas-phase analyzer (G2108, Picarro Inc. Santa Clara, CA, USA) based upon Cavity Ring Down Spectroscopy (CRDS) in the near-infrared, and discuss its performance. With a measurement interval of approximately 2 seconds, a precision of better than 40 parts-per-trillion (1 sigma, 30 seconds), and a response time of approximately 1-2 minutes (10 - 90% rise time or 90 - 10% fall time), this analyzer is well-suited for measurements of atmospherically-relevant concentrations of HCl, in both laboratory and field. CRDS provides very stable measurements and low drift, requiring infrequent calibration of the instrument, and can therefore be operated remotely for extended periods of time. In this work we also present results from a laboratory intercomparison of the Picarro G2108 analyzer and an iodide ion time-of-flight Chemical Ionization Mass Spectrometer (CIMS), and the results of the analyzer time response tests.

  16. A paradox: The thermal rate coefficient for the H+DCl → HCl+D exchange reaction

    International Nuclear Information System (INIS)

    Thompson, D.L.; Suzukawa, H.H. Jr.; Raff, L.M.

    1975-01-01

    Previously reported photolysis experiments indicate that the frequency factors associated with the hydrogen-exchange reactions H+DCl → HCl+D and D+HCl → DCl+H are on the order of 10 10 cm 3 /molcenter-dotsec. A series of unadjusted, quasiclassical trajectory calculations were been carried out to compute the thermal rate coefficients and activation parameters for a series of 13 thermal processes of the type A+BC → AB+C, where A=H, D, or Cl and BC=H 2 , D 2 , HCl, DCl, or Cl 2 . In addition, hot-atom yield ratios have been computed from the IRP equation for the reactions D*+DCl → D 2 +Cl, D*+Cl 2 → DCl + Cl as a function of the initial D* laboratory energy. The computations yield (1) hot-atom DCl/D 2 yield ratios within a factor of 2 of the experimental values; (2) thermal activation energies in satisfactory agreement with experiment for all processes investigated; and (3) frequency factors in reasonable accord with experiment for all the reactions except the hydrogen exchange reactions

  17. Recovery of actinides from actinide-aluminium alloys by chlorination: Part III - Chlorination with HCl(g)

    Science.gov (United States)

    Meier, Roland; Souček, Pavel; Walter, Olaf; Malmbeck, Rikard; Rodrigues, Alcide; Glatz, Jean-Paul; Fanghänel, Thomas

    2018-01-01

    Two steps of a pyrochemical route for the recovery of actinides from spent metallic nuclear fuel are being investigated at JRC-Karlsruhe. The first step consists in electrorefining the fuel in molten salt medium implying aluminium cathodes. The second step is a chlorination process for the separation of actinides (An) from An-Al alloys formed on the cathodes. The chlorination process, in turn, consists of three steps; the distillation of adhered salt (1), the chlorination of An-Al by HCl/Cl2 under formation of AlCl3 and An chlorides (2), and the subsequent sublimation of AlCl3 (3). In the present work UAl2, UAl3, NpAl2, and PuAl2 were chlorinated with HCl(g) in a temperature range between 300 and 400 °C forming UCl4, NpCl4 or PuCl3 as the major An containing phases, respectively. Thermodynamic calculations were carried out to support the experimental work. The results showed a high chlorination efficiency for all used starting materials and indicated that the sublimation step may not be necessary when using HCl(g).

  18. The nucleation of HCl and Cl{sub 2}-based HVPE GaN on mis-oriented sapphire substrates

    Energy Technology Data Exchange (ETDEWEB)

    Bohnen, Tim; Dreumel, Gerbe W.G. van; Enckevort, Willem J.P. van; Ashraf, Hina; Jong, Aryan E.F. de; Hageman, Paul R.; Vlieg, Elias [IMM, Radboud University, Nijmegen (Netherlands); Weyher, Jan L. [Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw (Poland)

    2010-07-15

    The nucleation of both classic HCl-based and novel Cl{sub 2{sup -}} based HVPE GaN on mis-oriented sapphire substrates was investigated. The use of Cl{sub 2}in HVPE increases the growth rate by a factor of 4-5 and strongly reduces the parasitic deposition, allowing for the growth of much thicker wafers than HCl-based HVPE. Morphological SEM surface studies of the HCl-based HVPE sample surface show that at 600 C a nanocrystalline layer is deposited on the sapphire. During the subsequent annealing phase, the morphology changes to a {mu}m-sized island structure. During overgrowth at 1080 C, the islands coalesce. Small voids or pinholes are then formed in between the coalescing GaN islands. These pinholes lead to numerous pits on the surface of the GaN at thicknesses of 5 {mu}m. The pits disappear during continued overgrowth and can no longer be found on the surface, when the GaN film reaches a thickness of 45 {mu}m. This particular coalescence mechanism also applies to Cl{sub 2}-based HVPE GaN on sapphire (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. The Impact of HCl Precleaning and Sulfur Passivation on the Al2O3/Ge Interface in Ge Metal-Oxide-Semiconductor Capacitors

    International Nuclear Information System (INIS)

    Xue Bai-Qing; Chang Hu-Dong; Sun Bing; Wang Sheng-Kai; Liu Hong-Gang

    2012-01-01

    Surface treatment for Ge substrates using hydrogen chlorine cleaning and chemical passivation are investigated on AuTi/Al 2 O 3 /Ge metal-oxide-semiconductor capacitors. After hydrogen chlorine cleaning, a smooth Ge surface almost free from native oxide is demonstrated by atomic force microscopy and x-ray photoelectron spectroscopy observations. Passivation using a hydrogen chlorine solution is found to form a chlorine-terminated surface, while aqueous ammonium sulfide pretreatment results in a surface terminated by Ge-S bonding. Compared with chlorine-passivated samples, the sulfur-passivated ones show less frequency dispersion and better thermal stability based on capacitance-voltage characterizations. The samples with HCl pre-cleaning and (NH 4 ) 2 S passivation show less frequency dispersion than the HF pre-cleaning and (NH 4 ) 2 S passivated ones. The surface treatment process using hydrogen chlorine cleaning followed by aqueous ammonium sulfide passivation demonstrates a promising way to improve gate dielectric/Ge interface quality. (condensed matter: structure, mechanical and thermal properties)

  20. Composition, morphology and surface recombination rate of HCl-isopropanol treated and vacuum annealed InAs(1 1 1)A surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Kesler, V.G., E-mail: kesler@isp.nsc.ru [Institute of Semiconductor Physics SB RAS, Lavrentiev av., 13, Novosibirsk 630090 (Russian Federation); Seleznev, V.A.; Kovchavtsev, A.P.; Guzev, A.A. [Institute of Semiconductor Physics SB RAS, Lavrentiev av., 13, Novosibirsk 630090 (Russian Federation)

    2010-05-01

    X-ray photoelectron spectroscopy and atomic force microscopy were used to examine the chemical composition and surface morphology of InAs(1 1 1)A surface chemically etched in isopropanol-hydrochloric acid solution (HCl-iPA) and subsequently annealed in vacuum in the temperature range 200-500 deg. C. Etching for 2-30 min resulted in the formation of 'pits' and 'hillocks' on the sample surface, respectively 1-2 nm deep and high, with lateral dimensions 50-100 nm. The observed local formations, whose density was up to 3 x 10{sup 8} cm{sup -2}, entirely vanished from the surface after the samples were vacuum-annealed at temperatures above 300 deg. C. Using a direct method, electron beam microanalysis, we have determined that the defects of the hillock type includes oxygen and excessive As, while the 'pits' proved to be identical in their chemical composition to InAs. Vacuum anneals were found to cause a decrease in As surface concentration relative to In on InAs surface, with a concomitant rise of surface recombination rate.

  1. Composition, morphology and surface recombination rate of HCl-isopropanol treated and vacuum annealed InAs(1 1 1)A surfaces

    Science.gov (United States)

    Kesler, V. G.; Seleznev, V. A.; Kovchavtsev, A. P.; Guzev, A. A.

    2010-05-01

    X-ray photoelectron spectroscopy and atomic force microscopy were used to examine the chemical composition and surface morphology of InAs(1 1 1)A surface chemically etched in isopropanol-hydrochloric acid solution (HCl-iPA) and subsequently annealed in vacuum in the temperature range 200-500 °C. Etching for 2-30 min resulted in the formation of "pits" and "hillocks" on the sample surface, respectively 1-2 nm deep and high, with lateral dimensions 50-100 nm. The observed local formations, whose density was up to 3 × 10 8 cm -2, entirely vanished from the surface after the samples were vacuum-annealed at temperatures above 300 °C. Using a direct method, electron beam microanalysis, we have determined that the defects of the hillock type includes oxygen and excessive As, while the "pits" proved to be identical in their chemical composition to InAs. Vacuum anneals were found to cause a decrease in As surface concentration relative to In on InAs surface, with a concomitant rise of surface recombination rate.

  2. Composition, morphology and surface recombination rate of HCl-isopropanol treated and vacuum annealed InAs(1 1 1)A surfaces

    International Nuclear Information System (INIS)

    Kesler, V.G.; Seleznev, V.A.; Kovchavtsev, A.P.; Guzev, A.A.

    2010-01-01

    X-ray photoelectron spectroscopy and atomic force microscopy were used to examine the chemical composition and surface morphology of InAs(1 1 1)A surface chemically etched in isopropanol-hydrochloric acid solution (HCl-iPA) and subsequently annealed in vacuum in the temperature range 200-500 deg. C. Etching for 2-30 min resulted in the formation of 'pits' and 'hillocks' on the sample surface, respectively 1-2 nm deep and high, with lateral dimensions 50-100 nm. The observed local formations, whose density was up to 3 x 10 8 cm -2 , entirely vanished from the surface after the samples were vacuum-annealed at temperatures above 300 deg. C. Using a direct method, electron beam microanalysis, we have determined that the defects of the hillock type includes oxygen and excessive As, while the 'pits' proved to be identical in their chemical composition to InAs. Vacuum anneals were found to cause a decrease in As surface concentration relative to In on InAs surface, with a concomitant rise of surface recombination rate.

  3. Studies on the effect of a newly synthesized Schiff base compound from phenazone and vanillin on the corrosion of steel in 2M HCl

    International Nuclear Information System (INIS)

    Emreguel, Kaan C.; Hayvali, Mustafa

    2006-01-01

    The inhibiting action of a Schiff base 4-[(4-hydroxy-3-hydroxymethyl-benzylidene)-amino]-1,5-dimethyl-2-phenyl-1,2 -dihydro-pyrazol-3-one (phv), derived from 4-amino-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazol-3-one (phz) and 4-hydroxy-3-methoxy-benzaldehyde (vn), towards the corrosion behavior of steel in 2M HCl solution has been studied using weight loss, polarization and electrochemical impedance spectroscopy (EIS) techniques. Although vn and phz were found to retard the corrosion rate of steel, the compound synthesized from vn and phz was seen to retard the corrosion rate even more. At constant temperature, the corrosion rate decreases with increasing inhibitor concentration. However, at any inhibitor concentration the increase in temperature leads to an increase in the corrosion rate of steel. The activations energies, ΔE a , as well as other thermodynamic parameters (ΔG ads 0 , ΔH ads 0 ) for the inhibitor process were calculated. The inhibitor efficiencies calculated from all the applied methods were in agreement and were found to be in the order: phv>phz>vn

  4. Copper corrosion in irradiated environments: The influence of H2O2 on the electrochemistry of copper dissolution in HCl electrolyte

    International Nuclear Information System (INIS)

    Smyrl, W.H.; Bell, B.T.; Atanasoski, R.T.; Glass, R.S.

    1986-12-01

    The anodic dissolution of copper was examined in deaerated, 0.1 M HCl aqueous solution in the presence of H 2 O 2 . Concentrations of H 2 O 2 up to 0.2 M were studied at a rotating copper disk-platinum ring electrode. The open circuit potential (OCP) of copper was found to depend on both peroxide concentration and rotation rate. The OCP shifts towards more positive values with increasing H 2 O 2 concentration (C) and decreasing rotation rate. The current-voltage curves for anodic dissolution of copper were also influenced by the presence of peroxide. The curves recorded with the potential scanned in the positive direction showed the expected 60 mV slope, but the reverse scans showed significant departures. At a given potential scan rate, hysteresis was observed which was larger for higher H 2 O 2 concentrations, lower rotation rates, and more positive anodic potential limits. Monitoring the cuprous ions at the outer Pt ring revealed that there was a complex set of events taking place at the copper surface, including film formation and the appearance of cupric ions. 13 refs., 7 figs

  5. Synthesis, Structure and Spectroscopy of Two Structurally Related Hydrogen Bonded Compounds in the dpma/HClO4 System; dpma (dimethylphosphorylmethanamine

    Directory of Open Access Journals (Sweden)

    Guido J. Reiss

    2013-06-01

    Full Text Available The new phosphine oxide compound, (dimethylphosphorylmethanaminium perchlorate, dpmaHClO4 (1, was synthesized by the reaction of (dimethylphosphoryl methanamine (dpma with concentrated perchloric acid. (Dimethylphosphorylmethanaminium perchlorate (dimethylphosphorylmethanamine solvate, dpmaHClO4•dpma (2 was obtained by the slow evaporation of an equimolar methanolic solution of 1 and dpma at room temperature. For both compounds, single-crystal X-ray structures, IR and Raman spectra are reported. The assignment of the spectroscopic data were supported by quantum chemical calculations at the B3LYP/6-311G(2d,p level of theory. In 1, the dpmaH cations form polymeric, polar double-strands along [010] by head to tail connections via N–H∙∙∙O hydrogen bonds. The perchlorate anions are located between these strands attached by one medium strong and two weaker un-bifurcated hydrogen bonds (monoclinic, centrosymmetric space group C2/c, a = 17.8796(5 Å, b = 5.66867(14 Å, c = 17.0106(5 Å, β = 104.788(3°, V = 1666.9(1 Å3, Z = 8, T = 293 K, R(F [I > 2σ(I] = 0.0391, wR(F2 [all] = 0.1113. In 2, besides the N–H∙∙∙O hydrogen bonds, medium strong N–H∙∙∙N hydrogen bonds are present. One dpmaH cation and the neutral dpma molecule are connected head to tail by two N–H∙∙∙O hydrogen bonds forming a monocationic cyclic unit. These cyclic units are further connected by N–H∙∙∙O and N–H∙∙∙N hydrogen bonds forming polymeric, polar double-strands along [001]. The perchlorate anions fill the gaps between these strands, and each [ClO4]− anion is weakly connected to the NH2 group by one N–H∙∙∙O hydrogen bond (orthorhombic, non-centrosymmetric space group Pca21 (No. 29, a = 18.5821(5 Å, b = 11.4320(3 Å, c = 6.89400(17 Å, V = 1464.50(6 Å3, Z = 4, T = 100 K, R(F [I > 2σ(I] = 0.0234, wR(F2 [all] = 0.0575. Both structures are structurally related, and their commonalities are discussed in terms of a graph

  6. Dilute-solution Structure of Charged Arborescent Graft Polymer

    International Nuclear Information System (INIS)

    Yun, Seok; Briber, R.M.; Kee, R. Andrew; Gauthier, Mario

    2006-01-01

    The solutions of charged G1 arborescent polystyrene-graft-poly(2-vinylpyridine) copolymers in methanol-d4 and D 2 O were investigated over a dilute concentration range φ = 0.005-0.05 (φ: mass fraction) using small-angle neutron scattering (SANS). Upon addition of acid (HCl) arborescent graft polymers became charged and a peak appeared in SANS data. The interparticle distance (d exp ) calculated from a peak position corresponded to the expected value (d uni ) for a uniform particle distribution. This indicates the formation of liquid-like ordering due to long-range Coulombic repulsions. The smaller dielectric constant of methanol-d4 resulted in long-range electrostatic repulsions persisting to lower polymer concentration than in D 2 O. The slow mode scattering was observed by dynamic light scattering measurements for the same polymer solutions, indicating the presence of structural inhomogeneity in the solutions. Both the peak and slow mode disappeared by addition of NaCl or excess HCl into the solutions due to the screening of electrostatic interactions. The G1 polymer grafted with longer P2VP chains (M w ∼ 30,000 versus 5000 g mol) formed a gel on addition of HCl. This result reveals that molecular expansion is more significant for arborescent polymers with longer (M w ∼ 30,000) linear polyelectrolyte branches, resulting in gelation for φ > 0.01. Upon addition of NaCl or excess HCl a gel transformed back to a liquid resulted from the screening of electrostatic interactions.

  7. Investigation of the oxidation states of Pu isotopes in a hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Lee, M.H. [Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, P. O. Box 105, Yuseong, Daejeon 305-353 (Korea, Republic of)], E-mail: mhlee@kaeri.re.kr; Kim, J.Y.; Kim, W.H.; Jung, E.C.; Jee, K.Y. [Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, P. O. Box 105, Yuseong, Daejeon 305-353 (Korea, Republic of)

    2008-12-15

    The characteristics of the oxidation states of Pu in a hydrochloric acid solution were investigated and the results were applied to a separating of Pu isotopes from IAEA reference soils. The oxidation states of Pu(III) and Pu(IV) were prepared by adding hydroxylamine hydrochloride and sodium nitrite to a Pu stock solution, respectively. Also, the oxidation state of Pu(VI) was adjusted with concentrated HNO{sub 3} and HClO{sub 4}. The stability of the various oxidation states of plutonium in a HCl solution with elapsed time after preparation were found to be in the following order: Pu(III){approx}Pu(VI)>Pu(IV)>Pu(V). The chemical recoveries of Pu(IV) in a 9 M HCl solution with an anion exchange resin were similar to those of Pu(VI). This method for the determination of Pu isotopes with an anion exchange resin in a 9 M HCl medium was applied to IAEA reference soils where the activity concentrations of {sup 239,240}Pu and {sup 238}Pu in IAEA-375 and IAEA-326 were consistent with the reference values reported by the IAEA.

  8. Solution of the Schrodinger Equation for a Diatomic Oscillator Using Linear Algebra: An Undergraduate Computational Experiment

    Science.gov (United States)

    Gasyna, Zbigniew L.

    2008-01-01

    Computational experiment is proposed in which a linear algebra method is applied to the solution of the Schrodinger equation for a diatomic oscillator. Calculations of the vibration-rotation spectrum for the HCl molecule are presented and the results show excellent agreement with experimental data. (Contains 1 table and 1 figure.)

  9. Spectrographic determination of strontium in yttrium-90 solutions

    International Nuclear Information System (INIS)

    Roca, M.; Capdevila, C.

    1970-01-01

    The copper spark method has been used for determining strontium in the concentration range 1-100 g/ml in yttrium-90 solutions containing 0,5 % or thereabouts of ammonium citrate. The influence of the citric acid as well as the ammonium citrate with regard to 2N HCL solutions has been studied: the citric acid enhances the line intensities of strontium. The employment of either barium or lanthanum as reference element compensates for this enhancement. Because of the increase in sensitivity mentioned above, the study of influence of the citric acid has been extended and several impurities usually determined in radioisotope solutions have been considered. (Author) 4 refs

  10. Changes in diapause related gene expression pattern during early embryonic development in HCl-treated eggs of bivoltine silkworm Bombyx mori (Lepidoptera: Bombycidae

    Directory of Open Access Journals (Sweden)

    Sirigineedi Sasibhushan

    2013-02-01

    Full Text Available Investigation of differential expression of diapause related genes (five metabolic, five heat shock protein and one translational regulatory in HCl-treated (non-diapause and untreated (diapause eggs of B. mori during early embryogenesis (up to 48h following oviposition revealed the up-regulation of sorbitol dehydrogenase upon HCl treatment, indicating increased glycogen synthesis for further embryonic development but, down-regulation of phosphofructo kinase gene expression after 18h of oviposition indicating an arrest of glycerol and sorbitol conversion. The expression of poly A binding protein gene expression was higher upon HCl treatment, revealing the initiation of translation. The expression levels of other genes analyzed did not vary significantly, except for Hsp90 and Hsp40, which were up-regulated on acid treatment until 18h. Thus, Sorbitoldehydrogenase and phosphofructo kinasegenes have a crucial role in diapause termination as evidenced by HCl treatment, while the other genes did not have major roles.

  11. Spectral shapes of Ar-broadened HCl lines in the fundamental band by classical molecular dynamics simulations and comparison with experiments

    Energy Technology Data Exchange (ETDEWEB)

    Tran, H., E-mail: ha.tran@lisa.u-pec.fr [Laboratoire Interuniversitaire des Systèmes Atmosphériques, UMR CNRS 7583, Université Paris Est Créteil, Université Paris Diderot, Institut Pierre-Simon Laplace, 94010 Créteil Cedex (France); Domenech, J.-L. [Instituto de Estructura de la Materia, Consejo Superior de Investigaciones Cientificas, (IEM-CSIC), Serrano 123, 28006 Madrid (Spain)

    2014-08-14

    Spectral shapes of isolated lines of HCl perturbed by Ar are investigated for the first time using classical molecular dynamics simulations (CMDS). Using reliable intermolecular potentials taken from the literature, these CMDS provide the time evolution of the auto-correlation function of the dipole moment, whose Fourier-Laplace transform leads to the absorption spectrum. In order to test these calculations, room temperature spectra of various lines in the fundamental band of HCl diluted in Ar are measured, in a large pressure range, with a difference-frequency laser spectrometer. Comparisons between measured and calculated spectra show that the CMDS are able to predict the large Dicke narrowing effect on the shape of HCl lines and to satisfactorily reproduce the shapes of HCl spectra at different pressures and for various rotational quantum numbers.

  12. Preparation and evaluation of poly(caprolactone fumarate nanoparticles containing doxorubicin HCl

    Directory of Open Access Journals (Sweden)

    N Shokri

    2011-03-01

    Full Text Available Background and the purpose of the study: Biodegradable Poly(caprolactone fumarate (PCLF has been used as bioresorbable sutures. In this study, doxorubicin HCl (Dox loaded PCLF nanoparticles were prepared and characterized.  Materials and methods: PCLFs were synthesized by polycondensation of PCL diols (Mws of 530, 1250 and 2000 with fumaryl chloride. The degradation of PCLF in NaOH, water and phosphate buffer saline (PBS, was determined in terms of Mw. Nanoparticles (NPs were prepared by two methods. In microemulsion polymerization method, dichloromethane containing PCLF and photoinitiator were combined with the water containing surfactants and then placed under light for crosslinking. In nanoprecipitation method, the organic solvent containing PCLF was poured into the stirring water. The effect of several variables concentration of PCLF, poly vinyl alcohol (PVA, Dox and Trypan blue (Trb and the Mw of PCLF and PVA on NP size and loading were evaluated. Results: PCLF 530, 1250 and 2000 in PBS or water were not degrade over 28 days. Nanoprecipitaion method gave spherical (revealed by SEM images stable NPs of about 225 with narrow size distribution and a zeta potential of -43 mV. The size of NP increased significantly with increase in Mw or concentration of PCLF. Although PVA was not necessary for formation of NPs but decreased the NP size. Dox loading and EE were 2.5-6.8% and 15-20%, respectively. Increasing the drug concentration, increased the drug loading (DL and NP size. The entrapment efficiency (EE for Trb ranged from 1% for PCLF530 to 6% for PCLF2000. An increase in PCLF concentration resulted in an increase in EE. Dox and Trb release showed a burst followed by 80% and 78% release during 3 and 4 days respectively.                                                                                                           

  13. Lactobacillus fermentum Suo Attenuates HCl/Ethanol Induced Gastric Injury in Mice through Its Antioxidant Effects

    Directory of Open Access Journals (Sweden)

    Huayi Suo

    2016-03-01

    Full Text Available The purpose of the study was to determine the inhibitory effects of Lactobacillus fermentum Suo (LF-Suo on HCl/ethanol induced gastric injury in ICR (Institute for Cancer Research mice and explain the mechanism of these effects through the molecular biology activities of LF-Suo. The studied mice were divided into four groups: healthy, injured, LF-Suo-L and LF-Suo-H group. After the LF-Suo intragastric administration, the gastric injury area was reduced compared to the injured group. The serum MOT (motilin, SP (substance P, ET (endothelin levels of LF-Suo treated mice were lower, and SS (somatostatin, VIP (vasoactive intestinal peptide levels were higher than the injured group mice. The cytokine IL-6 (interleukin 6, IL-12 (interleukin 12, TNF-α (tumor necrosis factor-α and IFN-γ (interferon-γ serum levels were decreased after the LF-Suo treatment. The gastric tissues SOD (superoxide dismutase, GSH-Px (glutathione peroxidase, NO (nitric oxide and activities of LF-Suo treated mice were increased and MDA (malondialdehyde activity was decreased compared to the injured group mice. By the RT-PCR assay, LF-Suo raised the occludin, EGF (epidermal growth factor, EGFR (epidermal growth factor receptor, VEGF (vascular endothelial growth factor, Fit-1 (fms-like tyrosine kinase-1, IκB-α (inhibitor kappaB-α, nNOS (neuronal nitric oxide synthase, eNOS (endothelial nitric oxide synthase, Mn-SOD, Cu/Zn-SOD, CAT (catalase mRNA or protein expressions and reduced the COX-2, NF-κB (nuclear factor kappaB, and iNOS (inducible nitric oxide synthase expressions in gastric tissues compared to the gastric injured group mice. A high concentration (1.0 × 109 CFU/kg b.w. of LF-Suo treatment showed stronger anti-gastric injury effects compared to a low concentration of (0.5 × 109 CFU/kg b.w. of LF-Suo treatment. LF-Suo also showed strong survival in pH 3.0 man-made gastric juice and hydrophobic properties. These results indicate that LF-Suo has potential use as

  14. Internal energy of HCl upon photolysis of 2-chloropropene at 193 nm investigated with time-resolved Fourier-transform spectroscopy and quasiclassical trajectories

    International Nuclear Information System (INIS)

    Chang, C.-M.; Huang, Y.-H.; Liu, S.-Y.; Lee, Y.-P.; Pombar-Perez, Marta; Martinez-Nunez, Emilio; Vazquez, Saulo A.

    2008-01-01

    Following photodissociation of 2-chloropropene (H 2 CCClCH 3 ) at 193 nm, vibration-rotationally resolved emission spectra of HCl (υ≤6) in the spectral region of 1900-2900 cm -1 were recorded with a step-scan time-resolved Fourier-transform spectrometer. All vibrational levels show a small low-J component corresponding to ∼400 K and a major high-J component corresponding to 7100-18 700 K with average rotational energy of 39± 3 11 kJ mol -1 . The vibrational population of HCl is inverted at υ=2, and the average vibrational energy is 86±5 kJ mol -1 . Two possible channels of molecular elimination producing HCl+propyne or HCl+allene cannot be distinguished positively based on the observed internal energy distribution of HCl. The observed rotational distributions fit qualitatively with the distributions of both channels obtained with quasiclassical trajectories (QCTs), but the QCT calculations predict negligible populations for states at small J. The observed vibrational distribution agrees satisfactorily with the total QCT distribution obtained as a weighted sum of contributions from both four-center elimination channels. Internal energy distributions of HCl from 2-chloropropene and vinyl chloride are compared.

  15. Adsorption and inhibitive properties of sildenafil (Viagra for zinc in hydrochloric acid solution

    Directory of Open Access Journals (Sweden)

    A.S. Fouda

    Full Text Available Sildenafil (Viagra was investigated as corrosion inhibitor for Zn in 1 M HCl solution using chemical and electrochemical methods at 25 °C. Electrochemical results showed that this drug is efficient inhibitor for Zn in HCl and the inhibition efficiency (IE reached to 91% at 300 ppm. The IE increases with the drug concentration and decreases with increasing temperature. The adsorption of this drug on Zn surface follows Langmuir adsorption isotherm. The polarization plots revealed that Sildenafil acts as a mixed-type inhibitor. The thermodynamic parameters of activation and adsorption were calculated and discussed. The surface morphology of the Zn specimens was evaluated using scanning electron microscope (SEM, energy dispersive X-ray (EDX, atomic force microscopy (AFM and Fourier transform infrared spectroscopy (FTIR techniques. Keywords: Zn, Corrosion inhibition, HCl, SEM, EDX, AFM, FTIR, Sildenafil drug

  16. Efficient saccharification by pretreatment of bagasse pith with ionic liquid and acid solutions simultaneously

    International Nuclear Information System (INIS)

    Wang, Gang; Zhang, Suping; Xu, Wenjuan; Qi, Wei; Yan, Yongjie; Xu, Qingli

    2015-01-01

    Highlights: • Bagasse pith was pretreated by BMIMCl solution containing HCl and water. • Hemicellulose was hydrolyzed to reducing sugars by HCl to maximize total sugar yield. • Cellulose was dissolved by BMIMCl and 95% of cellulose recovery was obtained. • The recovered cellulose was disrupted which is conducive to cellulase hydrolysis. • The total sugars yield is 89.9% obtained from pretreatment and cellulase hydrolysis. - Abstract: Hydrolysis of hemicellulose and disruption of cellulose during pretreatment process are conducive to the following cellulase hydrolysis performance. In this work, bagasse pith was first pretreated by 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) solution containing 0–1.2% hydrochloric acid (HCl) and 30% water. The water (30%) added into the acidic ionic liquid (IL) solutions led to an increase in the biomass loading up to a biomass/IL solutions ratio of 1:10 (wt.%). Hemicellulose was hydrolyzed to reducing sugars by HCl and cellulose was dissolved by [BMIM]Cl. In this process, 76.9% of hemicellulose conversion and 95% of cellulose recovery were obtained. The pretreated bagasse pith was then followed by hydrolysis with commercially available enzymes. The effects of pretreatment temperature, reaction time and acid concentration on cellulase hydrolysis of pretreated bagasse pith were investigated. Pretreatment of bagasse pith with [BMIM]Cl solutions containing 1.0% HCl at 120 °C for 30 min resulted in the glucose concentration of 92.3 g/l and yield of 94.5% after 72 h of cellulase hydrolysis. The maximum total reducing sugars yield reached to 89.9% after pretreatment and cellulase hydrolysis

  17. Novel Biodegradable Polyesters. Synthesis and Application as Drug Carriers for the Preparation of Raloxifene HCl Loaded Nanoparticles

    Directory of Open Access Journals (Sweden)

    Evangelos Karavas

    2009-07-01

    Full Text Available Raloxifene HCl is a drug with poor bioavailability and poor water solubility. Furthermore nο pharmaceutically acceptable organic solvent has been reported before to dilute the drug. It was observed that Raloxifene HCl can be diluted in a solvent mixture of acetone/water or ethanol/water. The aim of this study was to use biodegradable polymers in order to prepare Raloxifene HCl nanoparticles. For this purpose a series of novel biodegradable poly(ethylene succinate-co-propylene adipate P(ESu-co-PAd polyesters were synthesized following the polycondensation method and further, poly(ethylene succinate (PESu and poly(propylene adipate (PPAd were used. The prepared polyesters were characterized by intrinsic viscosity measurements, end group analysis, enzymatic hydrolysis, Nuclear Magnetic Resonance Spectroscopy (1Η-NMR and 13C-NMR and Wide-angle X-ray Diffractometry (WAXD. The drug nanoparticles have been prepared by a variation of the co-precipitation method and were studied by Wide-angle X-ray Diffractometry (WAXD, FTIR spectrometry, light scattering size distribution, Scanning Electron Microscopy (SEM and release behavior measurements. The interactions between the polymers and the drug seem to be limited, so the drug occurs in crystalline form in all nanoparticles. The size of the nanoparticles seems to be in the range of 150-350 nm, depending on the polymer that was used. The drug release depends on the melting point and degree of crystallinity of the polyesters used. An initial high release rate was recorded followed by very slow rates of controlled release.

  18. Dorsal Vagal Complex Modulates Neurogenic Airway Inflammation in a Guinea Pig Model With Esophageal Perfusion of HCl

    Directory of Open Access Journals (Sweden)

    Zhe Chen

    2018-05-01

    Full Text Available Neurogenic airway inflammation in chronic cough and bronchial asthma related to gastroesophageal reflux (GER is involved in the esophageal–bronchial reflex, but it is unclear whether this reflex is mediated by central neurons. This study aimed to investigate the regulatory effects of the dorsal vagal complex (DVC on airway inflammation induced by the esophageal perfusion of hydrochloric acid (HCl following the microinjection of nuclei in the DVC in guinea pigs. Airway inflammation was evaluated by measuring the extravasation of Evans blue dye (EBD and substance P (SP expression in the airway. Neuronal activity was indicated by Fos expression in the DVC. The neural pathways from the lower esophagus to the DVC and the DVC to the airway were identified using DiI tracing and pseudorabies virus Bartha (PRV-Bartha retrograde tracing, respectively. HCl perfusion significantly increased plasma extravasation, SP expression in the trachea, and the expression of SP and Fos in the medulla oblongata nuclei, including the nucleus of the solitary tract (NTS and the dorsal motor nucleus of the vagus (DMV. The microinjection of glutamic acid (Glu or exogenous SP to enhance neuronal activity in the DVC significantly potentiated plasma extravasation and SP release induced by intra-esophageal perfusion. The microinjection of γ-aminobutyric acid (GABA, lidocaine to inhibit neuronal activity or anti-SP serum in the DVC alleviated plasma extravasation and SP release. In conclusion, airway inflammation induced by the esophageal perfusion of HCl is regulated by DVC. This study provides new insight for the mechanism of airway neurogenic inflammation related to GER.

  19. HCl and ClO in activated Arctic air; first retrieved vertical profiles from TELIS submillimetre limb spectra

    Directory of Open Access Journals (Sweden)

    A. de Lange

    2012-02-01

    Full Text Available The first profile retrieval results of the Terahertz and submillimeter Limb Sounder (TELIS balloon instrument are presented. The spectra are recorded during a 13-h balloon flight on 24 January 2010 from Kiruna, Sweden. The TELIS instrument was mounted on the MIPAS-B2 gondola and shared this platform with the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS and the mini-Differential Optical Absorption Spectroscopy (mini-DOAS instruments. The flight took place within the Arctic vortex at an altitude of ≈34 km in chlorine activated air, and both active (ClO and inactive chlorine (HCl were measured over an altitude range of respectively ≈16–32 km and ≈10–32 km. In this altitude range, the increase of ClO concentration levels during sunrise has been recorded with a temporal resolution of one minute. During the daytime equilibrium, a maximum ClO level of 2.1 ± 0.3 ppbv has been observed at an altitude of 23.5 km. This equilibrium profile is validated against the ClO profile by the satellite instrument Microwave Limb Sounder (MLS aboard EOS Aura. HCl profiles have been determined from two different isotopes – H35Cl and H37Cl – and are also validated against MLS. The precision of all profiles is well below 0.01 ppbv and the overall accuracy is therefore governed by systematic effects. The total uncertainty of these effects is estimated to be maximal 0.3 ppbv for ClO around its peak value at 23.5 km during the daytime equilibrium, and for HCl it ranges from 0.05 to 0.4 ppbv, depending on altitude. In both cases the main uncertainty stems from a largely unknown non-linear response in the detector.

  20. Isotopic separation of carbon by dissociation of CF2HCl irradiated by a Q-modulated CO2 laser

    International Nuclear Information System (INIS)

    Ezubchenko, A.N.; Ilyukhin, A.I.; Karchevskii, A.I.; Krasnikov, N.S.; Merzylakov, A.V.; Soloukhin, A.B.

    1993-01-01

    Isotopic separation of carbon by selective dissociation of CF 2 HCl by radiation from a CO 2 laser with mechanical Q-modulation has been studied experimentally. The modulation frequency was 10 4 sec -1 with a 20 W output. The peak radiation intensity is increased by a factor of 20-100 when modulated, while the average power is 0.5-0.9 that of the laser when operating in continuous mode. The authors show that under these conditions, a separation coefficient on the order of 40-50 is achieved as well as a high degree of the target isotope extraction (70%)

  1. High-mobility germanium p-MOSFETs by using HCl and (NH4)2S surface passivation

    International Nuclear Information System (INIS)

    Xue Bai-Qing; Wang Sheng-Kai; Han Le; Chang Hu-Dong; Sun Bing; Zhao Wei; Liu Hong-Gang

    2013-01-01

    To achieve a high-quality high-κ/Ge interfaces for high hole mobility Ge p-MOSFET applications, a simple chemical cleaning and surface passivation scheme is introduced, and Ge p-MOSFETs with effective channel hole mobility up to 665 cm 2 /V·s are demonstrated on a Ge (111) substrate. Moreover, a physical model is proposed to explain the dipole layer formation at the metal—oxide—semiconductor (MOS) interface by analyzing the electrical characteristics of HCl- and (NH 4 ) 2 S-passivated samples. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  2. The activation controlled galvanic corrosion of Carbon Steel/Zinc couple in deaerated stirred 0.2 N HCl

    International Nuclear Information System (INIS)

    Saeed, F. M. M.; Slaiman, Q. J. M.

    2005-01-01

    The effect of galvanic coupling of carbon steel to zinc (C.S. /Zn) in Deaerated 0.2 N HCl was studied using the multiple zero resistance technique to measure the galvanic current (Ig) and the coupling potential (Ecop,) versus time for the coupled metals. It was found that altering area ratio (AR) (Cathode/Anode) of the coupled metals and increasing temperature played an important role in the increasing corrosion rate as well as changing the galvanic factor (GF), galvanic current (Ig), and dissolution current (Id), in most of the cases. (author)

  3. Influence of corrosive solutions on microhardness and chemistry of magnesium oxide /001/ surfaces

    Science.gov (United States)

    Ishigaki, H.; Miyoshi, K.; Buckley, D. H.

    1982-01-01

    X-ray photoelectron spectroscopy analyses and hardness experiments were conducted on cleaved magnesium oxide /001/ surfaces. The magnesium oxide bulk crystals were cleaved to specimen size along the /001/ surface, and indentations were made on the cleaved surface in corrosive solutions containing HCl, NaOH, or HNO3 and in water without exposing the specimen to any other environment. The results indicated that chloride (such as MgCl2) and sodium films are formed on the magnesium oxide surface as a result of interactions between an HCl-containing solution and a cleaved magnesium oxide surface. The chloride films soften the magnesium oxide surface. In this case microhardness is strongly influenced by the pH value of the solution. The lower the pH, the lower the microhardness. Sodium films, which are formed on the magnesium oxide surface exposed to an NaOH containing solution, do not soften the magnesium oxide surface.

  4. Surface coverage and corrosion inhibition effect of Rosmarinus officinalis and zinc oxide on the electrochemical performance of low carbon steel in dilute acid solutions

    Science.gov (United States)

    Loto, Roland Tolulope

    2018-03-01

    Electrochemical analysis of the corrosion inhibition and surface protection properties of the combined admixture of Rosmarinus officinalis and zinc oxide on low carbon steel in 1 M HCl and H2SO4 solution was studied by potentiodynamic polarization, open circuit potential measurement, optical microscopy and ATR-FTIR spectroscopy. Results obtained confirmed the compound to be more effective in HCl solution, with optimal inhibition efficiencies of 93.26% in HCl and 87.7% in H2SO4 acid solutions with mixed type inhibition behavior in both acids. The compound shifts the corrosion potential values of the steel cathodically in HCl and anodically in H2SO4 signifying specific corrosion inhibition behavior without applied potential. Identified functional groups of alcohols, phenols, 1°, 2° amines, amides, carbonyls (general), esters, saturated aliphatic, carboxylic acids, ethers, aliphatic amines, alkenes, aromatics, alkyl halides and alkynes within the compound completely adsorbed onto the steel forming a protective covering. Thermodynamic calculations showed physisorption molecular interaction with the steel's surface according to Langmuir and Frumkin adsorption isotherms. Optical microscopy images of the inhibited and uninhibited steels contrast each other with steel specimens from HCl solution showing a better morphology.

  5. Surface coverage and corrosion inhibition effect of Rosmarinus officinalis and zinc oxide on the electrochemical performance of low carbon steel in dilute acid solutions

    Directory of Open Access Journals (Sweden)

    Roland Tolulope Loto

    2018-03-01

    Full Text Available Electrochemical analysis of the corrosion inhibition and surface protection properties of the combined admixture of Rosmarinus officinalis and zinc oxide on low carbon steel in 1 M HCl and H2SO4 solution was studied by potentiodynamic polarization, open circuit potential measurement, optical microscopy and ATR-FTIR spectroscopy. Results obtained confirmed the compound to be more effective in HCl solution, with optimal inhibition efficiencies of 93.26% in HCl and 87.7% in H2SO4 acid solutions with mixed type inhibition behavior in both acids. The compound shifts the corrosion potential values of the steel cathodically in HCl and anodically in H2SO4 signifying specific corrosion inhibition behavior without applied potential. Identified functional groups of alcohols, phenols, 1°, 2° amines, amides, carbonyls (general, esters, saturated aliphatic, carboxylic acids, ethers, aliphatic amines, alkenes, aromatics, alkyl halides and alkynes within the compound completely adsorbed onto the steel forming a protective covering. Thermodynamic calculations showed physisorption molecular interaction with the steel’s surface according to Langmuir and Frumkin adsorption isotherms. Optical microscopy images of the inhibited and uninhibited steels contrast each other with steel specimens from HCl solution showing a better morphology. Keywords: Corrosion, Inhibitor, Adsorption, Steel, Acid

  6. Laser Raman spectra of mono-, oligo- and polysaccharides in solution

    Science.gov (United States)

    Barrett, T. W.

    We examined the Raman spectra of thirteen sugars—seven monosaccharides, two disaccharides, one trisaccharide and three polysaccharides—in the wavelength range 200—1700 cm -1 and (i) varied the phosphate buffered solution from pH 6.0 to 8.5 at constant ionic strength of 0.1 and (ii) varied HCl solutions from pH 0.8 to 5.0. As is to be expected with molecules containing COH groupings, all the molecular spectra are distinct. Of the thirteen sugars examined, only D-fructose 1,6-diphosphate (FDP) demonstrated spectral changes for the pH range 6.0—8.5 in phosphate buffer; but all exhibited band intensity enhancement in HCl at the lower pHs, but not band wavenumber changes. The results indicate that: (i) changes in the pH of the major intracellular buffer, phosphate, toward acidity, are able to hydrolyze the 1-phosphate group of FDP and the relative concentration of fructose 1-phosphate to fructose 6-phosphate is indicated by the intensity ratio of the 982 and 1080 cm -1 bands; (ii) it appears that all phosphate groups of FDP are hydrolyzed at pH 0.8 in HCl; and (iii) although conditions of extreme acidity are able to hydrolyze other sugars examined, there is no major degradation.

  7. Cyclohexanone microfluidic extraction of radioactive perrhenate from acid solutions

    Energy Technology Data Exchange (ETDEWEB)

    Dalmázio, Ilza [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Oehlke, Elisabeth, E-mail: E.Oehlke@tudelft.nl [Section Radiation and Isotopes for Health, Department of Radiation Science and Technology, Delft University of Technology (Netherlands)

    2017-07-01

    Several studies have investigated the application of microfluidic devices in extraction processes. A potential use of microfluidic devices is in radionuclide generators based on solvent extraction, as the {sup 188}W/{sup 188}Re generator. The aim of this work is to present the initial results of microfluidic solvent extraction of radioactive perrhenate. Aqueous solutions of ammonium perrhenate at 0.1 mg/mL (in water, HCl or sodium tungstate) were used as feed solution and cyclohexanone as extractant. As a first step, the fluid behaviour inside the glass microchannel was evaluated to reach laminar flow. The second step was the determination of extraction efficiency using thermal neutron activated perrhenate to produce feed solutions. The extraction conditions permitted liquid-liquid contact times as short as 0.5 s. Increasing of the contact time, resulted in a higher extraction efficiency of perrhenate, e.g. 14 % for 0.5 s and 32 % for 1.1 s using a 0.1 mol/L HCl feed solution. The extraction of perrhenate improved also when applying a feed solution with higher acidity, e.g. 52% for 1 mol/L HCl with contact time of 1.1 s. The influence of adding sodium tungstate to the feed solution was also examined. To the best of our knowledge, these are the first results related to perrhenate solvent extraction using a microfluidic device. The usefulness of microfluidic devices to screen extraction conditions was demonstrated making it possible to evaluate the effect of electrolytes on the perrhenate extraction process in a short time-frame. (author)

  8. Cyclohexanone microfluidic extraction of radioactive perrhenate from acid solutions

    International Nuclear Information System (INIS)

    Dalmázio, Ilza; Oehlke, Elisabeth

    2017-01-01

    Several studies have investigated the application of microfluidic devices in extraction processes. A potential use of microfluidic devices is in radionuclide generators based on solvent extraction, as the 188 W/ 188 Re generator. The aim of this work is to present the initial results of microfluidic solvent extraction of radioactive perrhenate. Aqueous solutions of ammonium perrhenate at 0.1 mg/mL (in water, HCl or sodium tungstate) were used as feed solution and cyclohexanone as extractant. As a first step, the fluid behaviour inside the glass microchannel was evaluated to reach laminar flow. The second step was the determination of extraction efficiency using thermal neutron activated perrhenate to produce feed solutions. The extraction conditions permitted liquid-liquid contact times as short as 0.5 s. Increasing of the contact time, resulted in a higher extraction efficiency of perrhenate, e.g. 14 % for 0.5 s and 32 % for 1.1 s using a 0.1 mol/L HCl feed solution. The extraction of perrhenate improved also when applying a feed solution with higher acidity, e.g. 52% for 1 mol/L HCl with contact time of 1.1 s. The influence of adding sodium tungstate to the feed solution was also examined. To the best of our knowledge, these are the first results related to perrhenate solvent extraction using a microfluidic device. The usefulness of microfluidic devices to screen extraction conditions was demonstrated making it possible to evaluate the effect of electrolytes on the perrhenate extraction process in a short time-frame. (author)

  9. A Promising Approach to Provide Appropriate Colon Target Drug Delivery Systems of Vancomycin HCL: Pharmaceutical and Microbiological Studies

    Directory of Open Access Journals (Sweden)

    Kadria A. Elkhodairy

    2014-01-01

    Full Text Available Vancomycin HCl was prepared as orally administered colon target drug delivery tablets for systemic therapy. Tablet matrices containing 10–60% of tablet weight of guar gum (F1–F6 were prepared by direct compression and subjected to in vitro release studies to explore their sustained release in the colon. Various synthetic and natural polymers were incorporated to F6 to modify the drug release rate. Different 15 matrix tablet formulations (F6–F20 were enteric coated with hydroxypropyl methyl cellulose phthalate. F6, F13 and F20 showed promising sustained release results having median dissolution time (MDT values: 8.25, 7.97, and 7.64, respectively. Microbiological assay was performed to test the efficacy of F6, F13, and F20 to inhibit clinical Staphylococcus aureus (SA isolates. Bactericidal activity of F6 was reached after 2, 4, and 24 hours of incubation against MSSA 18, MRSA 29, and MRSA 11 strains, respectively, while it was reached within 6–8 hours in case of F13, and F20 against all strains tested. F13 enhanced log microbial reduction by 1.74, 0.65 and 2.4 CFU/mL compared to F6 while it was 1, 2.57 and 1.57 compared to F20 against MSSA18, MRSA11 and MRSA29, respectively. Vancomycin HCl tablets displayed a promising sustained release in vitro and microbiological inhibitory action on all isolates tested.

  10. A promising approach to provide appropriate colon target drug delivery systems of vancomycin HCL: pharmaceutical and microbiological studies.

    Science.gov (United States)

    Elkhodairy, Kadria A; Afifi, Samar A; Zakaria, Azza S

    2014-01-01

    Vancomycin HCl was prepared as orally administered colon target drug delivery tablets for systemic therapy. Tablet matrices containing 10-60% of tablet weight of guar gum (F1-F6) were prepared by direct compression and subjected to in vitro release studies to explore their sustained release in the colon. Various synthetic and natural polymers were incorporated to F6 to modify the drug release rate. Different 15 matrix tablet formulations (F6-F20) were enteric coated with hydroxypropyl methyl cellulose phthalate. F6, F13 and F20 showed promising sustained release results having median dissolution time (MDT) values: 8.25, 7.97, and 7.64, respectively. Microbiological assay was performed to test the efficacy of F6, F13, and F20 to inhibit clinical Staphylococcus aureus (SA) isolates. Bactericidal activity of F6 was reached after 2, 4, and 24 hours of incubation against MSSA 18, MRSA 29, and MRSA 11 strains, respectively, while it was reached within 6-8 hours in case of F13, and F20 against all strains tested. F13 enhanced log microbial reduction by 1.74, 0.65 and 2.4 CFU/mL compared to F6 while it was 1, 2.57 and 1.57 compared to F20 against MSSA18, MRSA11 and MRSA29, respectively. Vancomycin HCl tablets displayed a promising sustained release in vitro and microbiological inhibitory action on all isolates tested.

  11. Plugging solution

    Energy Technology Data Exchange (ETDEWEB)

    Sharipov, A U; Yangirov, I Z

    1982-01-01

    A clay-powder, cement, and water-base plugging solution is proposed having reduced solution viscosity characteristics while maintaining tensile strength in cement stone. This solution utilizes silver graphite and its ingredients, by mass weight, are as follows: cement 51.2-54.3%; claypowder 6.06-9.1%; silver graphite 0.24-0.33%; with water making up the remainder.

  12. Lipids bearing extruded-spheronized pellets for extended release of poorly soluble antiemetic agent-Meclizine HCl.

    Science.gov (United States)

    Qazi, Faaiza; Shoaib, Muhammad Harris; Yousuf, Rabia Ismail; Nasiri, Muhammad Iqbal; Ahmed, Kamran; Ahmad, Mansoor

    2017-04-12

    Antiemetic agent Meclizine HCl, widely prescribed in vertigo, is available only in immediate release dosage forms. The approved therapeutic dose and shorter elimination half-life make Meclizine HCl a potential candidate to be formulated in extended release dosage form. This study was aimed to develop extended release Meclizine HCl pellets by extrusion spheronization using natural and synthetic lipids. Influence of lipid type, drug/lipid ratio and combinations of different lipids on drug release and sphericity of pellets were evaluated. Thirty two formulations were prepared with four different lipids, Glyceryl monostearate (Geleol ® ), Glyceryl palmitostearate (Precirol ® ), Glyceryl behenate (Compritol ® ) and Carnauba wax, utilized either alone or in combinations of drug/lipid ratio of 1:0.5-1:3. Dissolution studies were performed at variable pH and release kinetics were analyzed. Fourier transform infrared spectroscopy was conducted and no drug lipid interaction was found. Sphericity indicated by shape factor (e R ) varied with type and concentration of lipids: Geleol ® (e R  = 0.891-0.997), Precirol ® (e R  = 0.611-0.743), Compritol ® (e R  = 0.665-0.729) and Carnauba wax (e R  = 0.499-0.551). Highly spherical pellets were obtained with Geleol ® (Aspect ratio = 1.005-1.052) whereas irregularly shaped pellets were formed using Carnauba wax (Aspect ratio = 1.153-1.309). Drug release was effectively controlled by three different combinations of lipids: (i) Geleol ® and Compritol ® , (ii) Geleol ® and Carnauba wax and (iii) Geleol ® , Compritol ® and Carnauba wax. Scanning electron microscopy of Compritol ® pellets showed smooth surface with pores, whereas, irregular rough surface with hollow depressions was observed in Carnauba wax pellets. Energy dispersive spectroscopy indicated elemental composition of lipid matrix pellets. Kinetics of (i) Geleol ® and Compritol ® pellets, explained by Korsmeyer-Peppas (R 2  = 0.978-0.993) indicated

  13. Communication: A new ab initio potential energy surface for HCl-H2O, diffusion Monte Carlo calculations of D0 and a delocalized zero-point wavefunction.

    Science.gov (United States)

    Mancini, John S; Bowman, Joel M

    2013-03-28

    We report a global, full-dimensional, ab initio potential energy surface describing the HCl-H2O dimer. The potential is constructed from a permutationally invariant fit, using Morse-like variables, to over 44,000 CCSD(T)-F12b∕aug-cc-pVTZ energies. The surface describes the complex and dissociated monomers with a total RMS fitting error of 24 cm(-1). The normal modes of the minima, low-energy saddle point and separated monomers, the double minimum isomerization pathway and electronic dissociation energy are accurately described by the surface. Rigorous quantum mechanical diffusion Monte Carlo (DMC) calculations are performed to determine the zero-point energy and wavefunction of the complex and the separated fragments. The calculated zero-point energies together with a De value calculated from CCSD(T) with a complete basis set extrapolation gives a D0 value of 1348 ± 3 cm(-1), in good agreement with the recent experimentally reported value of 1334 ± 10 cm(-1) [B. E. Casterline, A. K. Mollner, L. C. Ch'ng, and H. Reisler, J. Phys. Chem. A 114, 9774 (2010)]. Examination of the DMC wavefunction allows for confident characterization of the zero-point geometry to be dominant at the C(2v) double-well saddle point and not the C(s) global minimum. Additional support for the delocalized zero-point geometry is given by numerical solutions to the 1D Schrödinger equation along the imaginary-frequency out-of-plane bending mode, where the zero-point energy is calculated to be 52 cm(-1) above the isomerization barrier. The D0 of the fully deuterated isotopologue is calculated to be 1476 ± 3 cm(-1), which we hope will stand as a benchmark for future experimental work.

  14. Novel cationic surfactants from fatty acids and their corrosion inhibition efficiency for carbon steel pipelines in 1 M HCl

    Directory of Open Access Journals (Sweden)

    A.M. Al-Sabagh

    2011-06-01

    Full Text Available Four fatty acids were used as a source of alkyl halides. Untraditionally tertiary amines were prepared by ethoxylation of aromatic and aliphatic fatty amines. These alkyl halide and tertiary amines were used to prepare 20 cationic quaternary ammonium surfactants (QASS. Their chemical structures were characterized and they tested as corrosion inhibitors for carbon steel in 1 M HCl solution. The corrosion inhibition efficiency was measured using, weight loss and potentiodynamic polarization methods. The inhibition efficiencies obtained from the two employed methods are nearly closed. From the obtained data it was found that, the inhibition efficiency increases with increasing the inhibitor concentration until the optimum one. Also, it was found that the inhibition efficiency of QASs which based on ethoxylated aromatic tertiary amine is greater than the obtained efficiencies by the QASs which based on ethoxylated aliphatic tertiary amines. The QASs based on alkyl halide C16 exhibited the maximum inhibition efficiency 98.8%. Adsorption of the inhibitors on the carbon steel surface was found to obey Langmuir’s adsorption isotherm. The quantum chemical calculations were done for some selected quaternary ammonium compounds based on their chemical structures QL1,4,5–QP3,4,5. The following quantum chemical indices such as the bond length, bond angle, charge density distribution, highest occupied molecular orbital (HOMO, lowest unoccupied molecular orbital (LUMO, energy gap ΔE = HOMO − LUMO, and dipole moment (u were considered. The relation between these parameters and the inhibition efficiencies was explained on the light of the chemical structure of the used inhibitors.

  15. Acetic and Acrylic Acid Molecular Imprinted Model Silicone Hydrogel Materials for Ciprofloxacin-HCl Delivery

    Directory of Open Access Journals (Sweden)

    Lyndon Jones

    2012-01-01

    Full Text Available Contact lenses, as an alternative drug delivery vehicle for the eye compared to eye drops, are desirable due to potential advantages in dosing regimen, bioavailability and patient tolerance/compliance. The challenge has been to engineer and develop these materials to sustain drug delivery to the eye for a long period of time. In this study, model silicone hydrogel materials were created using a molecular imprinting strategy to deliver the antibiotic ciprofloxacin. Acetic and acrylic acid were used as the functional monomers, to interact with the ciprofloxacin template to efficiently create recognition cavities within the final polymerized material. Synthesized materials were loaded with 9.06 mM, 0.10 mM and 0.025 mM solutions of ciprofloxacin, and the release of ciprofloxacin into an artificial tear solution was monitored over time. The materials were shown to release for periods varying from 3 to 14 days, dependent on the loading solution, functional monomer concentration and functional monomer:template ratio, with materials with greater monomer:template ratio (8:1 and 16:1 imprinted tending to release for longer periods of time. Materials with a lower monomer:template ratio (4:1 imprinted tended to release comparatively greater amounts of ciprofloxacin into solution, but the release was somewhat shorter. The total amount of drug released from the imprinted materials was sufficient to reach levels relevant to inhibit the growth of common ocular isolates of bacteria. This work is one of the first to demonstrate the feasibility of molecular imprinting in model silicone hydrogel-type materials.

  16. Real-time, high frequency (1 Hz), in situ measurement of HCl and HF gases in volcanic plumes with a novel cavity-enhanced, laser-based instrument

    Science.gov (United States)

    Kelly, P. J.; Sutton, A. J.; Elias, T.; Kern, C.; Clor, L. E.; Baer, D. S.

    2017-12-01

    Primary magmatic halogen-containing gases (HCl, HF, HBr, HI in characteristic order of abundance) are of great interest for volcano monitoring and research because, in general, they are more soluble in magma than other commonly-monitored volcanic volatiles (e.g. CO2, SO2, H2S) and thereby can offer unique insights into shallow magmatic processes. Nevertheless, difficulties in obtaining observations of primary volcanic halogens in gas plumes with traditional methods (e.g. direct sampling, Open-Path Fourier Transform Infrared spectroscopy, filter packs) have limited the number of observations reported worldwide, especially from explosive arc volcanoes. With this in mind, the USGS and Los Gatos Research, Inc. collaborated to adapt a commercially-available industrial in situ HCl-HF analyzer for use in airborne and ground-based measurements of volcanic gases. The new, portable instrument is based around two near-IR tunable diode lasers and uses a vibration-tolerant, enhanced-cavity approach that is well-suited for rugged field applications and yields fast (1 Hz) measurements with a wide dynamic range (0 -2 ppm) and sub-ppb precision (1σ: HCl: <0.4 ppb; HF: <0.1 ppb). In spring 2017 we conducted field tests at Kīlauea Volcano, Hawaii, to benchmark the performance of the new instrument and to compare it with an accepted method for halogen measurements (OP-FTIR). The HCl-HF instrument was run in parallel with a USGS Multi-GAS to obtain in situ H2O-CO2-SO2-H2S-HCl-HF plume compositions. The results were encouraging and quasi-direct comparisons of the in situ and remote sensing instruments showed good agreement (e.g. in situ SO2/HCl = 72 vs. OP-FTIR SO2/HCl = 88). Ground-based and helicopter-based measurements made 0 - 12 km downwind from the vent (plume age 0 - 29 minutes) show that plume SO2/HCl ratios increase rapidly from 60 to 300 around the plume edges, possibly due to uptake of HCl onto aerosols.

  17. Controlled release of tetracycline-HCl from halloysite-polymer composite films.

    Science.gov (United States)

    Ward, Christopher J; Song, Shang; Davis, Edward W

    2010-10-01

    The first direct comparison between two common methods for loading halloysite with a small molecule for controlled release is presented. While the methods differ in the degree of simplicity, they provide essentially the same level of loading and release kinetics. A tentative explanation of the "burst" effect often seen in the release of low molecular weight molecules from halloysite is provided. The ability of halloysite to mediate the release rate of a water soluble drug, tetracycline, from solution cast polyvinyl alcohol and polymethyl methacrylate films was evaluated. In some films, montmorillonite was also incorporated. The addition of montmorillonite to solutions used to cast tetracycline containing films significantly reduced the release rate from the dried films. The same overall effect was seen when the drug was loaded into halloysite prior to preparation of the films. In both cases, the release was best fit with the simple Higuchi model. However, when montmorillonite was added to solutions of polyvinyl alcohol and drug loaded halloysite the release profiles were better fit by the Ritgar-Peppas model for anomalous transport. Release from polymethyl methacrylate was reduced by a factor of three by incorporating the drug in halloysite prior to producing the films.

  18. Response of citrus and other selected plant species to simulated HCL - acid rain

    Science.gov (United States)

    Knott, W. M.; Heagle, A. S.

    1980-01-01

    Mature valencia orange trees were sprayed with hydrochloric acid solutions (pH 7.8, 2.0, 1.0, and 0.5) in the field at the full bloom stage and at one month after fruit set. Potted valencia orange and dwarf citrus trees, four species of plants native to Merritt Island, and four agronomic species were exposed to various pH levels of simulated acid rain under controlled conditions. The acid rain was generated from dilutions of hydrochloric acid solutions or by passing water through an exhaust generated by burning solid rocket fuel. The plants were injured severely at pH levels below 1.0, but showed only slight injury at pH levels of 2.0 and above. Threshold injury levels were between 2.0 and 3.0 pH. The sensitivity of the different plant species to acid solutions was similar. Foliar injury symptoms were representative of acid rain including necrosis of young tissue, isolated necrotic spots or patches, and leaf abscission. Mature valencia orange trees sprayed with concentrations of 1.0 pH and 0.5 pH in the field had reduced fruit yields for two harvests after the treatment. All experimental trees were back to full productivity by the third harvest after treatment.

  19. Uranyl fluoride luminescence in acidic aqueous solutions

    International Nuclear Information System (INIS)

    Beitz, J.V.; Williams, C.W.

    1996-01-01

    Luminescence emission spectra and decay rates are reported for uranyl species in acidic aqueous solutions containing HF or added NaF. The longest luminescence lifetime, 0.269 ± 0.006 ms, was observed from uranyl in 1 M HF + 1 M HClO 4 at 296 K and decreased with increasing temperature. Based on a luminescence dynamics model that assumes equilibrium among electronically excited uranyl fluoride species and free fluoride ion, this long lived uranyl luminescence in aqueous solution is attributed primarily to UO 2 F 2 . Studies on the effect of added LiNO 3 or Na 2 WO 4 ·2H 2 O showed relatively weak quenching of uranyl fluoride luminescence which suggests that high sensitivity determination of the UF 6 content of WF 6 gas should be feasible via uranyl luminescence analysis of hydrolyzed gas samples of impure WF 6

  20. Self-association and thermodynamic behavior of etilefrine hydrochloride in aqueous electrolyte solution

    International Nuclear Information System (INIS)

    Elmasry, Manal S.; Hassan, Wafaa S.; Elazazy, Marwa S.

    2014-01-01

    Highlights: • The self-association of etilefrine HCl in aqueous solution has been studied. • Conductivity and 1 H NMR measurements were used to study the self association. • The critical micelle concentrations and the degree of ionizations were calculated. • The effect of different temperatures and NaCl concentrations were studied. • The thermodynamic parameters of self association of etilefrine HCl were evaluated. - Abstract: The self-association (micellization) behavior of etilefrine HCl, an amphiphilic drug, in aqueous electrolyte solution has been investigated as a function of temperature and sodium chloride (NaCl) concentration by conductivity and 1 H NMR measurements. The critical micelle concentration (CMC) was calculated from the inflection in the data obtained from both techniques. The CMC and the degree of ionization (α) values were determined over the temperature range (298.15 to 313.15) K in water and in presence of different concentrations of NaCl. The thermodynamic parameters of micellization for etilefrine HCl i.e. the standard Gibbs free energy change ΔG° m , the standard enthalpy change, ΔH° m , and the standard entropy change, ΔS° m , were evaluated according to the pseudo-phase model. The obtained CMC values, in presence and absence of electrolyte, showed an inverted U-shaped behavior. While the degree of micelle ionization (α) showed a linear response to the increase in temperature in absence of electrolyte, addition of NaCl did not cause a specific response

  1. Monitoring corrosion and corrosion control of iron in HCl by non-ionic surfactants of the TRITON-X series - Part III. Immersion time effects and theoretical studies

    International Nuclear Information System (INIS)

    Amin, Mohammed A.; Ahmed, M.A.; Arida, H.A.; Kandemirli, Fatma; Saracoglu, Murat; Arslan, Taner; Basaran, Murat A.

    2011-01-01

    Graphical abstract: . Display Omitted Research highlights: → The inhibition effect of TX-100, TX-165 and TX-305 on iron corrosion in 1.0 M HCl was studied. → TX-305 inhibited iron corrosion more effectively than TX-100 and TX-165. → In most cases, inhibition efficiency increased with time during the first 60 min of immersion, then decreased. → Calculated quantum chemical parameters confirmed the experimental inhibition efficiencies of the tested surfactants. - Abstract: The inhibition performance of three selected non-ionic surfactants of the TRITON-X series, namely TRITONX-100 (TX-100), TRITON-X-165 (TX-165) and TRITON-X-305 (TX-305), on the corrosion of iron was studied in 1.0 M HCl solutions as a function of inhibitor concentration (0.01-0.20 g L -1 ) and immersion time (0.0-8 h) at 298 K. Measurements were conducted based on Tafel polarization, LPR and impedance studies. At high frequencies, the impedance spectrum showed a depressed capacitive loop in the complex impedance plane, whose diameter is a function of the immersion time and the type and concentration of the introduced surfactant. In all cases, an inductive loop was observed in the low frequency and this could be attributed to the adsorption behavior. The inhibition efficiency increased with immersion time, reached a maximum and then decreased. This was attributed to the orientation change of adsorbed surfactant molecules. TX-305 inhibited iron corrosion more effectively than TX-100 and TX-165. The frontier orbital energies, the energy gap between frontier orbitals, dipole moments (μ), charges on the C and O atoms, the polarizabilities, and the quantum chemical descriptors were calculated. The quantum chemical calculation results inferred that for the HOMO representing the condensed Fukui function for an electrophilic attack (f k + ), the contributions belong to the phenyl group and the oxygen atom attached to the phenyl group for each tested surfactant. Quantitative structure

  2. Exploring the limits of cryospectroscopy: Least-squares based approaches for analyzing the self-association of HCl

    Science.gov (United States)

    De Beuckeleer, Liene I.; Herrebout, Wouter A.

    2016-02-01

    To rationalize the concentration dependent behavior observed for a large spectral data set of HCl recorded in liquid argon, least-squares based numerical methods are developed and validated. In these methods, for each wavenumber a polynomial is used to mimic the relation between monomer concentrations and measured absorbances. Least-squares fitting of higher degree polynomials tends to overfit and thus leads to compensation effects where a contribution due to one species is compensated for by a negative contribution of another. The compensation effects are corrected for by carefully analyzing, using AIC and BIC information criteria, the differences observed between consecutive fittings when the degree of the polynomial model is systematically increased, and by introducing constraints prohibiting negative absorbances to occur for the monomer or for one of the oligomers. The method developed should allow other, more complicated self-associating systems to be analyzed with a much higher accuracy than before.

  3. Study of Gallium Arsenide Etching in a DC Discharge in Low-Pressure HCl-Containing Mixtures

    Science.gov (United States)

    Dunaev, A. V.; Murin, D. B.

    2018-04-01

    Halogen-containing plasmas are often used to form topological structures on semiconductor surfaces; therefore, spectral monitoring of the etching process is an important diagnostic tool in modern electronics. In this work, the emission spectra of gas discharges in mixtures of hydrogen chloride with argon, chlorine, and hydrogen in the presence of a semiconducting gallium arsenide plate were studied. Spectral lines and bands of the GaAs etching products appropriate for monitoring the etching rate were determined. It is shown that the emission intensity of the etching products is proportional to the GaAs etching rate in plasmas of HCl mixtures with Ar and Cl2, which makes it possible to monitor the etching process in real time by means of spectral methods.

  4. A theoretical investigation of gaseous absorption by water droplets from SO2-HNO3-NH3-CO2-HCl mixtures

    Science.gov (United States)

    Adewuyi, Y. G.; Carmichael, G. R.

    1982-01-01

    A physical-chemical model is developed and used to investigate gaseous absorption by water droplets from trace gas mixtures. The model is an extension of that of Carmichael and Peters (1979) and includes the simultaneous absorption of SO2, NH3, HNO3, CO2, and HCl. Gas phase depletion is also considered. Presented results demonstrate that the absorption behavior of raindrops is strongly dependent on drop size, fall distance, trace gas concentrations, and the chemical and physical properties of the constituents of the mixture. In addition, when gas phase depletion is considered, the absorption rates and equilibrium values are also dependent on the precipitation rate itself. Also, the trace constituents liquid phase concentrations may be a factor of six or more lower when gas depletion is considered then when the depletion is ignored. However, the hydrogen ion concentration may be insensitive to the gas phase depletion.

  5. Consequences of Anode Interfacial Layer Deletion. HCl-Treated ITO in P3HT:PCBM-Based Bulk-Heterojunction Organic Photovoltaic Devices

    Science.gov (United States)

    2010-01-01

    followed by centrifugation. P3HT53was purchased from RiekeMetals, Inc., andwas further purified by sequential Soxhlet extractions with methanol and...19.8 nA (σ=31.1 nA, Figure 2c), and scanning under the same conditions on HCl-treated ITO yields Imean=9.11 nA (σ=12.5 nA, Figure 2d). As seen...0.01:1.0, and the respective combination ofHCl treatment and 10minUVOalso yields 0.23( 0.01:1.0, remarkably similar to an ITO surface treated with RIE

  6. An HPLC tandem mass spectrometry for quantification of ET-26-HCl and its major metabolite in plasma and application to a pharmacokinetic study in rats.

    Science.gov (United States)

    Chen, Xu; Zhang, Wensheng; Rios, Sandy; Morkos, Miriam B; Ye, Xiaoli; Li, Gen; Jiang, Xuehua; Wang, Zhijun; Wang, Ling

    2018-02-05

    ET-26-HCl is a new analog of etomidate, a short-acting anesthetic drug, with less adrenal cortex inhibition. The pharmacokinetics of ET-26-HCl in rats needs to be determined for future clinical trials in human subjects. In order to facilitate the pharmacokinetic study, a liquid chromatography based tandem mass spectrometric (HPLC-MS/MS) method was developed and validated for quantification of ET-26-HCl and its major metabolite, ET-26-acid. These two compounds and gabapentin (internal standard) were extracted using a protein precipitation method with methanol and detected by Multiple Reaction Monitoring of m/z transition of 275.6-170.9, 217.7-113.1, and 172.5-154.3 for ET-26-HCl, ET-26-acid, and gabapentin respectively. This method was validated in terms of sensitivity, linearity, reproducibility, and stability. The HPLC-MS/MS method was found linear over the concentration ranges of 21.76-4352ng/mL, and 18.62-3724ng/mL with LLOQ of 21.76 and 18.62ng/mL for ET-26-HCl and ET-26-acid respectively. The mean intra-day and inter-day accuracy was between 94.11-107.78%, while the precision was within the limit of 15.0% for all the quality control samples. A pharmacokinetic study was then conducted in rats following intravenous injection of 2.1, 4.2, and 8.4mg/kg. The linear pharmacokinetics of ET-26-HCl was observed over the dose range of 2.1-8.4mg/kg. The average terminal phase elimination half-lives were 0.87 and 1.03h for ET-26-HCl and ET-26-acid respectively. In summary, an HPLC-MS/MS method for quantification of ET-26-HCl in rat plasma has been developed and successfully applied to a pharmacokinetic study. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Vanadium Flow Battery Electrolyte Synthesis via Chemical Reduction of V2O5 in Aqueous HCl and H2SO4.

    Energy Technology Data Exchange (ETDEWEB)

    Small, Leo J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Pratt, Harry [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Staiger, Chad [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Martin, Rachel Irene [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Anderson, Travis Mark [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Chalamala, Babu [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Soundappan, Thiagarajan [Univ. of Washington, Seattle, WA (United States); Tiwari, Monika [Univ. of Washington, Seattle, WA (United States); Subarmanian, Venkat R. [Univ. of Washington, Seattle, WA (United States)

    2017-01-01

    We report a simple method to synthesize V 4+ (VO 2+ ) electrolytes as feedstock for all- vanadium redox flow batteries (RFB). By dissolving V 2 O 5 in aqueous HCl and H 2 SO 4 , subsequently adding glycerol as a reducing agent, we have demonstrated an inexpensive route for electrolyte synthesis to concentrations >2.5 M V 4+ (VO 2+ ). Electrochemical analysis and testing of laboratory scale RFB demonstrate improved thermal stability across a wider temperature range (-10-65 degC) for V 4+ (VO 2+ ) electrolytes in HCl compared to in H 2 SO 4 electrolytes.

  8. Comparative analysis of adsorption and corrosion inhibitive properties of ethanol extract of Dialium Guineense leaves for mild steel in 0.5 M HCl

    OpenAIRE

    Shola Elijah Adeniji; Bamigbola Abiola Akindehinde

    2018-01-01

    Adsorption and corrosion inhibitive properties of ethanol extract of Dialium guineense leaves for mild steel in 0.5M HCl was studied using the gravimetric method. The results showed that the ethanol extract of Dialium guineense leaves is a good corrosion inhibitor for mild steel in 0.5 M HCl. The inhibition efficiency was found to increase with increase in the concentration of ethanol extract of Dialium guineense leaves up to the maximum of 92 %, but at the same time it decreased as the tempe...

  9. Effects of sucralfate, cimetidine and rabeprazole on mucosal hydroxyproline content in healing of ethanol-hcl-induced gastric lesions.

    Science.gov (United States)

    Arisawa, Tomiyasu; Shibata, Tomoyuki; Kamiya, Yoshio; Nagasaka, Mitsuo; Nakamura, Masakatsu; Fujita, Hiroshi; Hasegawa, Shin; Harata, Masao; Nakamura, Masahiko; Mizuno, Tamaki; Tahara, Tomomitsu; Ohta, Yoshiji; Nakano, Hiroshi

    2006-07-01

    1. No general consensus has been reached on the treatment of acute gastric lesions. The aims of the present study were to clarify the effects of sucralfate, cimetidine and rabeprazole monotherapies and combination therapies on acute gastric lesions from the viewpoint of connective tissue regeneration. 2. Gastric lesions were experimentally created by the oral administration of 50% ethanol-0.15 mol/L HCl to rats. After 30 min, the anti-ulcer agents sucralfate (100 mg/kg), cimetidine (20 mg/kg) and rabeprazole (2 mg/kg) were administered separately or in combination and the stomach was excised at different times to measure the level of hydroxyproline in the gastric mucosa and determine lesion index. Immunostaining against prolylhydroxylase was performed on some specimens. 3. In the control group, lesion index decreased linearly from 30 min after ethanol-HCl administration and the level of mucosal hydroxyproline peaked between 2 and 4 h later. Although sucralfate significantly promoted lesion healing, it had no effect on mucosal hydroxyproline level. Cimetidine suppressed increases in mucosal hydroxyproline and prolonged lesion healing, but these findings were reversed by combining cimetidine and sucralfate. Rabeprazole had no significant effect on lesion healing, but promoted lesion healing in combination with sucralfate. Immunohistochemical analysis showed that prolylhydroxylase was expressed in spindle cells that lined the glandular cells in a boundary area between normal and injured tissues. 4. Under conditions in which the effects of intragastric pH are minimal, sucralfate is superior to antisecretory agents in promoting the healing of acute gastric lesions.

  10. [Reparative regeneration of rat skin under influence of hollow cathode lamp (HCL) with manganese and copper line spectrum emission].

    Science.gov (United States)

    Mel'nikova, V I; Izvol'skaia, M S; Voronova, S N; Sharipova, M M; Rukin, E M; Zakharova, L A

    2010-01-01

    Influence of local light exposure by hollow cathode lamp with typical manganese and copper (HCL-Mn, Cu) line emission spectrum on posttraumatic regeneration rate of rat skin has been investigated. We performed the comparative analysis of the morphology and the differentiation ability of rat skin on the 15th and 24th days after full-thickness skin wound had been inflicted on rat dorsums. On the 15th day after injury, the experimental group (daily 30 s exposure for two weeks) showed scab loss, re-epithelialization, and hair regrowth, in contrast to the control rats, where scabs were still observed on the 24th day. Histological analysis revealed that in contrast to the control group the treatment with HCL-Mn, Cu resulted in the increased number of hair follicles and sebaceous glands, the decreased number of blood vessels and horizontal orientation of collagen fibers. The immunohistochemistry for OX-62 revealed that the number of dermal dendritic cells in the experimental groups was maximal on the 15th day, and then decreased to the 24th day after injury. The number of dermal dendritic cells was significantly lower in the control group. The immunohistochemistry for pan-keratins in the control animals revealed a high number of cells expressing different types of keratins, distributed in the main part of the epidermis on the 15th day after surgery, whereas in the experimental group the number of such cells was significantly lower and the cells were concentrated more close to the external part of the epidermis. The number of cells stained for keratin 19 was higher in the experimental group on the 15th day after surgery, whereas this number decreased in this group on the 24th day after surgery as compared to the control group. Thus, typical manganese and copper line spectrum emission emitted by hollow cathode lamp stimulates innate immunity, accelerates restoration of derma, skin epithelium and other skin derivates, and stimulates wound healing in general.

  11. Bio resorbability of the modified hydroxyapatite in Tris-HCL buffer

    International Nuclear Information System (INIS)

    Golovanova, O A; Izmailov, R R; Ghyngazov, S A

    2016-01-01

    The solubility of carbonated hydroxyapatite powders and granulated carbonated hydroxyapatite produced from the synovial biofluid model solution has been studied. The kinetic characteristics of dissolution were determined. It was found that the solubility of carbonated hydroxyapatite is higher as compared to that of hydroxyapatite. The impact of the organic matrix on the rate of sample dissolution was revealed. For HA-gelatin composites, as the gelatin concentration grows, the dissolution rate becomes greater, and a sample of 6.0 g / L concentration has higher resorbability. The results of the research can be used to study the kinetics of dissolution and the biocompatibility of ceramic materials for medicine, namely for reconstructive surgery, dentistry, and development of drug delivery systems. (paper)

  12. Extraction of Uranium with Amin as solvent and HCl as internal phase at membrane emulsion

    International Nuclear Information System (INIS)

    Ninik Bintarti, A.; Bambang-Edi-HB; Sudibyo, R.

    1996-01-01

    An extraction process of uranium by Tri-n-Actylamine(TOA) solution with kerosene as thinner and surfactant of Span-80 as emulgator to bend a membrane emulsion. HCI 0.01 N is used as an internal phase uranium in HNO 3 as feed and butanol is used to split the membrane. In the case of membrane, the result was 1 % vol. TOA and 5 % vol. Span-80, emulsification time was 30 minutes and 50 % vol. HCI 0.01 N. The product of an extraction was concentration of HNO 3 is 3 M. The time of extraction 20 minutes and uranium concentration in feed of 600 ppm will give distribution coefficient of membrane extraction was 5.830 and coefficient of stripping was 0.276

  13. Potentiometric titration of polyhexamethylene biguanide hydrochloride with potassium poly(vinyl sulfate) solution using a cationic surfactant-selective electrode.

    Science.gov (United States)

    Masadome, Takashi; Yamagishi, Yuichi; Takano, Masaki; Hattori, Toshiaki

    2008-03-01

    A potentiometric titration method using a cationic surfactant as an indicator cation and a plasticized poly(vinyl chloride) membrane electrode sensitive to the cationic surfactant is proposed for the determination of polyhexamethylene biguanide hydrochloride (PHMB-HCl), which is a cationic polyelectrolyte. A sample solution of PHMB-HCl containing an indicator cation (hexadecyltrimethylammonium ion, HTA) was titrated with a standard solution of an anionic polyelectrolyte, potassium poly(vinyl sulfate) (PVSK). The end-point was detected as a sharp potential change due to an abrupt decrease in the concentration of the indicator cation, HTA, which is caused by its association with PVSK. The effects of the concentrations of HTA ion and coexisting electrolytes in the sample solution on the degree of the potential change at the end-point were examined. A linear relationship between the concentration of PHMB-HCl and the end-point volume of the titrant exists in the concentration range from 2.0 x 10(-5) to 4.0 x 10(-4) M in the case that the concentration of HTA is 1.0 x 10(-5) M, and that from 1.0 x 10(-6) to 1.2 x 10(-5) M in the case that the concentration of HTA is 5.0 x 10(-6) M, respectively. The proposed method was applied to the determination of PHMB-HCl in some contact-lens detergents.

  14. Fabrications of Polyaniline Films by Pulse Electrodeposition in Acidic Solutions with Different Anions and Their Thermoelectric Performances

    Science.gov (United States)

    Yang, Weifang; Xu, Han; Li, Yuanyuan; Wang, Wei

    2017-08-01

    Polymerization of aniline was prepared by the pulse potentiostatic method in H3PO4, HClO4 and H2SO4 acidic solutions. The morphologies and thermoelectric performances were analyzed by scanning electron microscopy, Seebeck coefficient ( S) and resistivity ( R) measurements. The results show that flake polyaniline (PANI) films can be obtained in H3PO4 and HClO4 acidic solutions, and porous PANI films with nanofiber-overlapped structures can be prepared in H2SO4 solution under the same pulse parameters. PANI films prepared in the three solutions are all p-type thermoelectric materials. PANI films polymerized in H2SO4 solution possess the highest S (30.2 μV K-1) and lowest R (1.6 × 10-3 Ω m) compared with those prepared in H3PO4 and HClO4 solutions, indicating that nanofiber-overlapped structures formed in H2SO4 solution contribute better thermoelectric performance. In addition, the effects of pulse parameters (anodic potential φ a, anodic pulse duration t a and cathodic pulse duration t c) on the surface morphologies and thermoelectric performances of PANI films were systematically investigated.

  15. Formulation of Convenient, Easily Scalable, and Efficient Granisetron HCl Intranasal Droppable Gels.

    Science.gov (United States)

    Ibrahim, Howida K; Abdel Malak, Nevine S; Abdel Halim, Sally A

    2015-06-01

    Deacetylated gellan gum and two sodium alginate polymer types were used each at three concentrations in the suitable range for their sol-gel transition. The prepared nine droppable gels were evaluated in vitro, ex vivo through sheep nasal mucosa, as well as in vivo in comparison to drug solution given intravenously and orally at the same dose. The prepared formulas gelled instantaneously in simulated nasal fluid and the obtained gels sustained their shear thinning and thixotropic behavior up to 48 h. Polymer type and concentration had significant effects on the apparent viscosities and the in vitro release profile of granisetron from the prepared gels. The drug release data best fitted a modified Higuchi equation with initial burst and followed Fickian diffusion mechanism. A 0.5% gellan-gum-based formula sustained the in vitro drug release up to 3 h and enhanced the drug permeation without need for an enhancer. The histopatholgical study revealed the safety of the tested formula. Intranasal delivery recorded double the drug bioavailabilty in comparison to the oral route. It had an absolute bioavailability of 0.6539 and the maximum plasma drug concentration reached after 1.5 h. The developed formula could be promising for the management of chemotherapy-induced nausea and vomiting regarding its improved bioavailability, patient acceptability, and ease of production.

  16. Kinetics of Oxidation of Metochlopramide withChloramine-T in HClO4 Medium

    Directory of Open Access Journals (Sweden)

    K. M. Meenakshi

    2009-01-01

    Full Text Available The kinetics of oxidation of metochlopramide hydrochloride (MCP with sodium N-chloro p-toluenesulfonamide (CAT in perchloric acid solution has been studied at 313K. The reaction rate shows a first order dependence on [CAT], fractional order on [MCP] and inverse fractional order on [H+]. There is a negative effect of dielectric constant of the solvent. The addition of the reduction product of CAT has no significant effect on the rate. The rate remained unchanged with the variation in the ionic strength of the medium. The reaction fails to induce the polymerization of acrylonitrile. Thermodynamic parameters have been computed by Arrhenius plot. The stoichiometry of the reaction was found to be 1:2 and oxidation products were identified. The Michaelis-Menten type of kinetics has been proposed. CH3C6H4SO2NHCl have been assumed to be the reactive oxidizing species. Thermodynamic parameters were computed by studying reactions at different temperatures. A mechanism consistent with observed kinetics is proposed.

  17. Solution preparation

    International Nuclear Information System (INIS)

    Seitz, M.G.

    1982-01-01

    Reviewed in this statement are methods of preparing solutions to be used in laboratory experiments to examine technical issues related to the safe disposal of nuclear waste from power generation. Each approach currently used to prepare solutions has advantages and any one approach may be preferred over the others in particular situations, depending upon the goals of the experimental program. These advantages are highlighted herein for three approaches to solution preparation that are currently used most in studies of nuclear waste disposal. Discussion of the disadvantages of each approach is presented to help a user select a preparation method for his particular studies. Also presented in this statement are general observations regarding solution preparation. These observations are used as examples of the types of concerns that need to be addressed regarding solution preparation. As shown by these examples, prior to experimentation or chemical analyses, laboratory techniques based on scientific knowledge of solutions can be applied to solutions, often resulting in great improvement in the usefulness of results

  18. An oilwell cement slurry additivated with bisphenol diglycidil ether/isophoronediamine-Kinetic analysis and multivariate modelings at slurry/HCl interfaces

    International Nuclear Information System (INIS)

    Cestari, Antonio R.; Vieira, Eunice F.S.; Tavares, Andrea M.G.; Andrade, Marcos A.S.

    2009-01-01

    Loss of zonal isolation in oilwell cementing operations leads to safety and environmental problems. The use of new cement slurries can help to solve this problem. In this paper, an epoxy-modified cement slurry was synthesized and characterized. The features of the modified slurries were evaluated in relation to a standard cement slurry (w/c = 0.50). A kinetic study of HCl interaction with the slurries was carried out using cubic molds. The Avrami kinetic model appears to be the most efficient in describing kinetic isotherms obtained from 25 to 55 deg. C. Type of slurry, HCl concentration and temperature effects were also evaluated in HCl adsorption onto cement slurries considering a 2 3 full factorial design. From the statistical analysis, it is inferred that the factor 'HCl concentration' has shown a profound influence on the numerical values of the Avrami kinetic constants. However, the best statistical fits were found using binary and tertiary interactive effects. It was found that the epoxy-modified cement slurry presents a good potential to be used in environmental-friendly oilwell operations.

  19. Study of the hydrolysis of acetonitrile using different brønsted acid models : zeolite-type and HCl(H2O)x clusters

    NARCIS (Netherlands)

    Barbosa, Louis; Santen, van R.A.

    2000-01-01

    The hydrolysis of acetonitrile has been studied theoretically by different ab initio methods (RHF, DFT, and MP2). Two Brønsted acid catalysts have been compared: zeolite and HCl(H2O)x=2,1 clusters. Some interesting analogies have been found for the reaction path catalyzed by these different acids,

  20. Acetone enhances the direct analysis of Procyanidin- and Prodelphinidin-based condensed tannins in lotus species by the butanol-HCl-iron assay

    Science.gov (United States)

    The butanol-HCl spectrophotometric assay is widely used for quantifying extractable and insoluble condensed tannins (CT, syn. proanthocyanidins) in foods, feeds, and foliage of herbaceous and woody plants, but the method underestimates total CT content when applied directly to plant material. To imp...

  1. Redesign of a Grignard-Based Active Pharmaceutical Ingredient (API) Batch Synthesis to a Flow Process for the Preparation of Melitracen HCl

    DEFF Research Database (Denmark)

    Pedersen, Michael J.; Skovby, Tommy; Mealy, Michael J.

    2018-01-01

    A Grignard-based batch process, for the preparation of Melitracen HCl, has been redesigned to fit a continuous reactor system. The Grignard addition is carried out at room temperature, with subsequent hydrolysis of the magnesium alkoxide intermediate followed by dehydration of the resulting alcoh...

  2. Determination of HCl and VOC Emission from Thermal Degradation of PVC in the Absence and Presence of Copper, Copper(II Oxide and Copper(II Chloride

    Directory of Open Access Journals (Sweden)

    Ahamad J. Jafari

    2009-01-01

    Full Text Available Polyvinyl chloride (PVC has played a key role in the development of the plastic industry over the past 40 years. Thermal degradation of PVC leads to formation of many toxic pollutants such as HCl, aromatic and volatile organic carbon vapors. Thermal degradation of PVC and PVC in the present of copper, cupric oxide and copper(II chloride were investigated in this study using a laboratory scale electrical furnace. HCl and Cl- ion were analyzed by a Dionex ion chromatograph and VOCs compounds were analyzed using GC or GC-MS. The results showed that HCl plus Cl- ion and benzene formed about 99% and 80% respectively in the first step of thermal degradation under air atmosphere. The presence of cupric oxide increases the percentage of short chain hydrocarbons more than 184% and decreases the amount of the major aromatic hydrocarbon and HCl plus Cl- ion to 90% and 65% respectively. The total aromatic hydrocarbon emitted less than when atmosphere was air and difference was statistically significant (Pvalue<0.000

  3. Perbandingan Penggunaan Topikal Spray Benzidamin HCl 0,15% dan Gel Lidokain 2% pada Pipa Endotrakeal terhadap Kejadian Nyeri Tenggorok Pascaintubasi Endotrakeal

    Directory of Open Access Journals (Sweden)

    Maulana Muhammad

    2015-08-01

    Full Text Available Postoperative sore throat is common and unpleasant after endotracheal anesthesia. This study was conducted to determine whether the use of benzydamine hcl 0.15% can further reduce the incidence of sore throat compared to lidocaine gel 2% in patients under endotracheal anesthesia. This experimental study was a randomized control trial (RCT in 90 patients with ASA physical status I–II, aged 18–60 years who underwent elective surgery in the central surgical operating room of Dr. Hasan Sadikin General Hospital during the period of June to August 2014. Patients were divided in benzydamine group, lidocaine group, and NaCl group. The hemodynamic changes were noted during surgery. The endotracheal tube cuff pressure was maintained below 25 mmHg and a graded scale for sore throat was performed at 2 hours, 6 hours, and 24 hours (T2, T6, T24 after surgery. Statistical tests using t-test, Kruskal-Wallis, and chi-square test were conducted. From the results, the incidence of sore throat in the benzydamine HCL group was significantly lower than in the lidoccaine HCL group at 6 hours after surgery (T6; p<0.05. It is concluded that benzydamin HCL 0.15% spray is able to reduce the incidence of postoperative sore throat when compared to lidocaine 2% gel.

  4. Coating of Silk Fabric Using PVA/Ciprofloxacin Hcl Nanofibers for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Somaye Baghersad

    2016-05-01

    Full Text Available In recent years, fabrication of polymeric antibacterial wound dressing has gained most attention in controlling wound infections. Silk is also a member of the broad family of protein-based polmers. The silk produced by the lepidopteran insect Bombyx mori is a highly accepted material due to its long history as a very valuable textile fiber. Recently, additional applications have been developed for silk, mainly in the field of biotechnology. Regarding its importance in wound healing, silk fabric was incorporated with ciprofloxacin, as an antibiotic, on its surface coated with electro-spun PVA/ciprofloxacin nanofibers. Before coating, degumming was carried out using autoclave technique and properties of the silk fabric, before and after degumming process, was investigated by SEM, FTIR, mechanical properties and moisture absorbance measurement. The results of all analyses showed a reduction in fibers diameter, mechanical strength and moisture absorption after degumming process. Electrospinning condition was optimized and diameter of the nanofibers, with and without drug, was measured before coating. The results showed that addition of the drug increased electrical conductivity of electrospinning solution and resulted in finer nanofibers. Antibacterial test was performed using "disk diffusion method" with Escherichia coli (EC and Staphylococcus aureus (SA bacteria to compare the antibacterial properties of degummed and non-degummed silk fabrics alone and coated with nanofibers. Measurement of bacterial inhibition zone diameter showed no antibacterial activity for degummed and non-degummed silk fabrics alone. However, the sample coated with PVA/ciprofloxacin showed antibacterial activity. The antibacterial property for SA in both cases was the same, but for EC, the antibacterial activity of degummed silk fabric was more than that of non-degummed material.

  5. Catalytic destruction of perchlorate in ferric chloride and hydrochloric acid solution with control of temperature, pressure and chemical reagents

    Science.gov (United States)

    Gu, Baohua; Cole, David R.; Brown, Gilbert M.

    2004-10-05

    A method is described to decompose perchlorate in a FeCl.sub.3 /HCl aqueous solution such as would be used to regenerate an anion exchange resin used to remove perchlorate. The solution is mixed with a reducing agent, preferably an organic alcohol and/or ferrous chloride, and can be heated to accelerate the decomposition of perchlorate. Lower temperatures may be employed if a catalyst is added.

  6. Bulk monocrystal growth, optical, dielectric, third order nonlinear, thermal and mechanical studies on HCl added L-alanine: An organic NLO material

    Energy Technology Data Exchange (ETDEWEB)

    Shkir, Mohd, E-mail: shkirphysics@gmail.com [Advanced Functional Materials & Optoelectronic Laboratory (AFMOL), Physics Department, Faculty of Science, King Khalid University, Abha (Saudi Arabia); Yahia, I.S., E-mail: dr_isyahia@yahoo.com [Advanced Functional Materials & Optoelectronic Laboratory (AFMOL), Physics Department, Faculty of Science, King Khalid University, Abha (Saudi Arabia); Nano-Science & Semiconductor Labs, Physics Department, Faculty of Education, Ain Shams University, Roxy, Cairo (Egypt); Al-Qahtani, A.M.A. [Advanced Functional Materials & Optoelectronic Laboratory (AFMOL), Physics Department, Faculty of Science, King Khalid University, Abha (Saudi Arabia)

    2016-12-01

    In the current work, good quality bulk size (∼32 mm × 23 mm × 10 mm) single crystals of HCl added L-alanine with well-defined morphology are successfully grown using slow evaporation technique. Crystal structure and other structural parameters were evaluated from X-ray diffraction data. Vibrational assessment of the grown crystal was done by FT-Raman analysis. The presence of chlorine and good quality of the grown crystal was confirmed by SEM/EDX analysis. Solid state UV–Vis–NIR diffused reflectance was measured and direct and indirect optical band gap was calculated using Kubelka-Munk relation and found to be 5.64 and 5 eV respectively. Dielectric measurement was carried out in high frequency range. Third order nonlinear optical susceptibility value was found to be enhanced from 1.91 × 10{sup −6} (pure) to 8.6 × 10{sup −6} esu (LAHCl). Good thermal stability of grown crystals was confirmed from DSC analysis. The enhancement in mechanical strength and crystalline perfection was also observed. - Highlights: • Bulk size (32 mm × 23 mm × 10 mm), good crystalline perfection HCl added L-alanine monocrystal is grown. • The shift in X-ray diffraction and vibrational peaks confirms the interaction of HCl. • The high optical transparency and band gap confirms its application in optoelectronic devices. • Third order NLO properties are found to be enhanced in HCl added L-alanine crystals. • The mechanical strength of the grown crystals is found to be enhanced due HCl addition.

  7. Extraction of niobium and tantalum isotopes using organophosphorus compounds. Pt. 1. Extraction of 'carrier-free' metal concentrations from HCl solutions

    International Nuclear Information System (INIS)

    Gates, J.M.; California Univ., Berkeley, CA; Sudowe, R.; Stavsetra, L.

    2009-01-01

    The extraction of niobium (Nb) and tantalum (Ta) from hydrochloric acid media by bis(2-ethylhexyl) hydrogen phosphate (HDEHP) and bis(2-ethylhexyl) hydrogen phosphite (BEHP) was studied. The goal of the experiments is to find a system that demonstrates selectivity between the members of group five of the Periodic Table and is also suitable for the study of dubnium (Db, Z=105). Experiments were performed at the trace level (10 -16 M Nb or Ta) using hydrochloric acid with concentrations ranging from 1-11 M and short-lived isotopes of Nb and Ta produced in nuclear reactions. When HDEHP was used as the extractant, the Nb extraction yield decreased with increasing acid concentrations above 6 M, while the amount of Ta extracted remained over 75% for all acid concentrations studied. Tantalum was found to be extracted by BEHP at acid concentrations above 6 M, while niobium was not significantly extracted. The data obtained are used as the basis to discuss the speciation of Nb and Ta under the conditions studied and to evaluate possible extraction mechanisms. (orig.)

  8. The interfacial tension of the mercury —1 M HClO4− solution interface at high potentials; comparison with double-layer capacitance measurements

    NARCIS (Netherlands)

    Sluyters-Rehbach, M.; Woittiez, W.J.A.; Sluyters, J.H.

    Interfacial tension values have been measured in order to calculate the electrical charge density as a function of potential. The results are in accordance with those obtained from double-layer capacitance data reported earlier2,3, also at highly positive potentials.

  9. Modified spectrophotometer for multi-dimensional circular dichroism/fluorescence data acquisition in titration experiments: application to the pH and guanidine-HCI induced unfolding of apomyoglobin.

    Science.gov (United States)

    Ramsay, G; Ionescu, R; Eftink, M R

    1995-01-01

    In a previous paper (Ramsay and Eftink, Biophys. J. 66:516-523) we reported the development of a modified spectrophotometer that can make nearly simultaneous circular dichroism (CD) and fluorescence measurements. This arrangement allows multiple data sets to be collected during a single experiment, resulting in a saving of time and material, and improved correlation between the different types of measurements. The usefulness of the instrument was shown by thermal melting experiments on several different protein systems. This CD/fluorometer spectrophotometer has been further modified by interfacing with a syringe pump and a pH meter. This arrangement allows ligand, pH, and chemical denaturation titration experiments to be performed while monitoring changes in the sample's CD, absorbance, fluorescence, and light scattering properties. Our data acquisition program also has an ability to check whether the signals have approached equilibrium before the data is recorded. For performing pH titrations we have developed a procedure which uses the signal from a pH meter in a feedback circuit in order to collect data at evenly spaced pH intervals. We demonstrate the use of this instrument with studies of the unfolding of sperm whale apomyoglobin, as induced by acid pH and by the addition of guanidine-HCI. Images FIGURE 2 PMID:8527683

  10. Labeling by ( sup 3 H)1,3-di(2-tolyl)guanidine of two high affinity binding sites in guinea pig brain: Evidence for allosteric regulation by calcium channel antagonists and pseudoallosteric modulation by sigma ligands

    Energy Technology Data Exchange (ETDEWEB)

    Rothman, R.B.; Reid, A.; Mahboubi, A.; Kim, C.H.; De Costa, B.R.; Jacobson, A.E.; Rice, K.C. (National Institute of Mental Health, Bethesda, MD (USA))

    1991-02-01

    Equilibrium binding studies with the sigma receptor ligand ({sup 3}H)1,3-di(2-tolyl)guanidine (({sup 3}H)DTG) demonstrated two high affinity binding sites in membranes prepared from guinea pig brain. The apparent Kd values of DTG for sites 1 and 2 were 11.9 and 37.6 nM, respectively. The corresponding Bmax values were 1045 and 1423 fmol/mg of protein. Site 1 had high affinity for (+)-pentazocine, haloperidol, (R)-(+)-PPP, carbepentane, and other sigma ligands, suggesting a similarity with the dextromethorphan/sigma 1 binding site described by Musacchio et al. (Life Sci. 45:1721-1732 (1989)). Site 2 had high affinity for DTG and haloperidol (Ki = 36.1 nM) and low affinity for most other sigma ligands. Kinetic experiments demonstrated that ({sup 3}H)DTG dissociated in a biphasic manner from both site 1 and site 2. DTG and haloperidol increased the dissociation rate of ({sup 3}H)DTG from site 1 and site 2, demonstrating the presence of pseudoallosteric interactions. Inorganic calcium channel blockers such as Cd2+ selectively increased the dissociation rate of ({sup 3}H)DTG from site 2, suggesting an association of this binding site with calcium channels.

  11. Labeling by [3H]1,3-di(2-tolyl)guanidine of two high affinity binding sites in guinea pig brain: Evidence for allosteric regulation by calcium channel antagonists and pseudoallosteric modulation by sigma ligands

    International Nuclear Information System (INIS)

    Rothman, R.B.; Reid, A.; Mahboubi, A.; Kim, C.H.; De Costa, B.R.; Jacobson, A.E.; Rice, K.C.

    1991-01-01

    Equilibrium binding studies with the sigma receptor ligand [ 3 H]1,3-di(2-tolyl)guanidine ([ 3 H]DTG) demonstrated two high affinity binding sites in membranes prepared from guinea pig brain. The apparent Kd values of DTG for sites 1 and 2 were 11.9 and 37.6 nM, respectively. The corresponding Bmax values were 1045 and 1423 fmol/mg of protein. Site 1 had high affinity for (+)-pentazocine, haloperidol, (R)-(+)-PPP, carbepentane, and other sigma ligands, suggesting a similarity with the dextromethorphan/sigma 1 binding site described by Musacchio et al. [Life Sci. 45:1721-1732 (1989)]. Site 2 had high affinity for DTG and haloperidol (Ki = 36.1 nM) and low affinity for most other sigma ligands. Kinetic experiments demonstrated that [ 3 H]DTG dissociated in a biphasic manner from both site 1 and site 2. DTG and haloperidol increased the dissociation rate of [ 3 H]DTG from site 1 and site 2, demonstrating the presence of pseudoallosteric interactions. Inorganic calcium channel blockers such as Cd2+ selectively increased the dissociation rate of [ 3 H]DTG from site 2, suggesting an association of this binding site with calcium channels

  12. Interaction of indium trichloride with calcium carbonate in aqueous solutions

    International Nuclear Information System (INIS)

    Kochetkova, N.V.; Toptygina, G.M.; Soklakova, O.V.; Evdokimov, V.I.

    1991-01-01

    Interaction of indium trichloride with calcium carbonate in aqueous solutions was studied, using methods of potentiometry, isothermal solubility and physicochemical computer simulating. The Gibb's energy value for crystal indium trihydroxide formation was calculated on the basis of experimental data on In(OH) 3 solubility. The value obtained was used for estimating equilibrium composition of InCl 3 -HCl-CaCO 3 -CO 2 -H 2 O system at a temperature of 25 deg C and carbon dioxide partial pressure of 0.05 to 1 at

  13. Role of Metal Cations on the corrosion behaviour of 8090-T851 in a pH 2.0 solution

    DEFF Research Database (Denmark)

    Murthy, K.S.N.; Ambat, Rajan; Dwarakadasa, E.S.

    1994-01-01

    The influence of cations such as Cu2+, Al3+ and Li+ on the corrosion behaviour of 8090-T851(Al-Li) alloy in a pH 2.0 HCl solution was investigated by weight loss and polarisation techniques. Weight loss experiments showed that the effect of cation is a strong function of its nature...

  14. Formation of fine solid particles from aqueous solutions of sodium chloropalladate by gamma-ray irradiation

    International Nuclear Information System (INIS)

    Hatada, Motoyoshi; Fujita, Iwao; Korekawa, Kei-ichi.

    1994-10-01

    Studies have been carried out on the radiation chemical formation of palladium fine particles in argon saturated aqueous solutions of sodium chloropalladate without organic stabilizer. The solutions were irradiated with gamma-rays from a cobalt gamma-ray source and the irradiated solutions were subjected to the dynamic light scattering analysis for the particle diameter measurements, and to the UV-visible optical absorption spectroscopy for the measurements of turbidity (absorption at 700 nm) and remaining chloropalladate ion concentrations in the solution. In the solution of pH = 1.95 by HCl, the turbidity increased after the irradiation and then decreased with time. The concentration of remaining palladate ion in the solution decreased by the irradiation, but it gradually increased with time after the irradiation. These phenomena were qualitatively explained by the reaction scheme in that a precursor to the solid particles still exists in the solution after the irradiation was terminated, and that intermediates including the precursor reacted with chloride ion to re-form chloropalladate ions. The average diameter of the particles after the irradiation was ca. 20 nm and it increased with time to 40 nm at 2.75 kGy, and to 80 nm at 8.25 kGy absorption of radiation. The solution of pH = 0.65 by HCl was found to give lower yields of particles than those observed for the solution of pH = 1.95, and to give the particles of diameters about 150-200 nm. In the solution containing HClO 4 instead of HCl, palladium particles were also formed by the irradiation, whereas no backward reaction after the irradiation was observed due to the low concentration of chloride ion in the solution. The average diameter of the particles after the irradiation was about 300 nm and increased with time after the irradiation to a final values which was found to depend on pH of the solution and dose. (author)

  15. Nanoethosomes for transdermal delivery of tropisetron HCl: multi-factorial predictive modeling, characterization, and ex vivo skin permeation.

    Science.gov (United States)

    Abdel Messih, Hanaa A; Ishak, Rania A H; Geneidi, Ahmed S; Mansour, Samar

    2017-06-01

    The aim of the present work is to exclusively optimize and model the effect of phospholipid type either egg phosphatidylcholine (EPC) or soybean phosphatidylcholine (SPC), together with other formulation variables, on the development of nano-ethosomal systems for transdermal delivery of a water-soluble antiemetic drug. Tropisetron HCl (TRO) is available as hard gelatin capsules and IV injections. The transdermal delivery of TRO is considered as a novel alternative route supposing to improve BAV as well as patient convenience. TRO-loaded ethanolic vesicular systems were prepared by hot technique. The effect of formulation variables were optimized through a response surface methodology using 3 × 2 2 -level full factorial design. The concentrations of both PC (A) and ethanol (B) and PC type (C) were the factors, while entrapment efficiency (Y 1 ), vesicle size (Y 2 ), polydispersity index (Y 3 ), and zeta potential (Y 4 ) were the responses. The drug permeation across rat skin from selected formulae was studied. Particle morphology, drug-excipient interactions, and vesicle stability were also investigated. The results proved the critical role of all formulation variables on ethosomal characteristics. The suggested models for all responses showed good predictability. Only the concentration of phospholipid, irrespective to PC type, had a significant effect on the transdermal flux (p transdermal TRO delivery.

  16. Evaluation of Ocimum basilicum L. seed mucilage as rate controlling matrix for sustained release of propranolol HCl

    Directory of Open Access Journals (Sweden)

    Majid Saeedi

    2015-01-01

    Full Text Available Polysaccharide mucilage derived from the seeds of Ocimum basilicum L. (family Lamiaceae was investigated for use in matrix formulations containing propranolol hydrochloride. Basil mucilage was extracted and several tablets were formulated. The effect of mucilage on drug release rate was evaluated in comparison with tablets containing two kinds of hydroxypropyl methylcellulose (HPMC K4M and HPMC K100M as standard polymer. The release data were fitted to several models for kinetic evaluation. The results showed that hardness decreased and friability of tablets increased as the concentration of mucilage increased. The rate of release of propranolol HCl from O. basilicm mucilage matrices was mainly controlled by the drug: mucilage ratio. Drug release was slower from the HPMC K4M and HPMCK100M containing tablets compared to the mucilage containing matrices than the drug release from matrices containing O. basilicum seed mucilage in similar ratios.  Formulations containing O. basilicm mucilage were found to exhibit suitable release pattern. The results of kinetic analysis showed that in tablets containing O. basilicm mucilage the highest correlation coefficient was achieved with the zero order model. The swelling and erosion studies revealed that, as the proportion of mucilage in tablets was increased, there was a corresponding increase in percent swelling and a decrease in percent erosion of tablets.

  17. Modeling study of vibrational photochemical isotope enrichment. [HBr + Cl/sub 2/; HCl + Br/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Badcock, C.C.; Hwang, W.C.; Kalsch, J.F.

    1978-09-29

    Chemical kinetic modeling studies of vibrational-photochemical isotope enrichment have been performed on two systems: Model (I), H/sup 79/Br(H/sup 81/Br) + Cl/sub 2/ and, Model (II), H/sup 37/Cl(H/sup 35/Cl) + Br. Pulsed laser excitation was modeled to the first excited vibrational level of H/sup 79/Br in Model I and the first and second excited vibrational levels of both HCl isotopes in Model II. These are prototype systems of exoergic (Model I) and endoergic (Model II) reactions. The effects on enrichment of varying the external parameters (pressure, laser intensity) and the internal parameters (rate constants for V-V exchange and excited-state reactions) were examined. Studies of these prototype systems indicate that a favorable reaction for enrichment, with isotopically-specific excitation and a significantly accelerated vibrationally-excited-state reaction should have the following properties: the reaction from v = 0 should be only moderately exoergic, and the most favorable coreactant should be a polyatomic species, such as alkyl radical. Direct excitation of the reacting vibrational level is at least an order of magnitude more favorable for enrichment than is population by energy transfer. Enrichment of the minor isotope by these processes is more effective than is major isotope enrichment. Within limits, increased laser intensity is beneficial. However, for sequential excitation of a second vibrational level, major isotope enrichment can be diminished by high populations of the first vibrational level.

  18. Ultrasound-assisted HCl-NaCl leaching of lead-rich and antimony-rich oxidizing slag.

    Science.gov (United States)

    Zhang, Rong Liang; Zhang, Xiao Fei; Tang, Shu Zhen; Huang, Ai Dong

    2015-11-01

    Lead-rich and antimony-rich oxidizing slag was subjected to regular HCl-NaCl leaching, with the experimental conditions optimized under which ultrasound was introduced. After only 15 min of ultrasound-assisted leaching, the leaching rate of Sb resembled that after 45 min of regular leaching. Ultrasonic treatment considerably elevated the leaching rates of Sb and Pb, and shortened the leaching time. With the decrease of particle size, the leaching rate of Sb and Pb increased gradually. Especially, as the particle size of the slag was greater than 0.217 mm, the ultrasonic leaching effects of Sb and Pb were significantly higher than that of regular leaching effects. The temperature exhibited great effect on ultrasonic leaching performance. As the temperature increased, the leaching rates of Sb and Pb increased step by step. In case the temperature was higher than 85°C, the increasing speed of the leaching rates for Sb and Pb tended to be slow. Increasing ultrasonic power could augment the leaching rate or accelerate the procedure till the same leaching rate. However, since ultrasound failed to energize the formation of new reaction pathways, the maximum leaching rates of Sb and Pb were determined by their phase compositions rather than by ultrasonic field. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Semiclassical study of the collision of a highly excited Rydberg atom with the molecules HF and HCl

    International Nuclear Information System (INIS)

    Kimura, M.; Lane, N.F.

    1990-01-01

    The semiclassical impact-parameter method is applied to the processes of state changing and energy transfer in the collision of a highly excited Rydberg atom (n≥20) with the polar molecules HF and HCl. The relative motion of the molecule and atomic nucleus is taken to be rectilinear; the electron-molecule and ion core-molecule interactions are represented by cutoff dipole forms. Cross sections for transitions involving quantum numbers n and l of the atom and rotational quantum number j of the molecule are obtained for a range of collision energies and initial atomic and molecular states. Comparisons are made with the results of earlier classical studies and with the quantum-mechanical impulse approximation. Collision rates are calculated and compared with experimental values for l mixing and n and j changing. The agreement between experiment and theory is shown to be satisfactory, within the uncertainties of both the measurements and the theory. Cases of agreement and disagreement between various theories are examined. One finding of the present work is that the quantum-mechanical impulse approximation appears to significantly overestimate the values of various state-changing cross sections when the internal energy defect is small. The validity of the impulse approximation for collisions of Rydberg atoms with polar molecules is discussed

  20. Determination of clemastine hydrogen fumarate, desloratadine, losartan potassium and moxepril HCl through binary complex formation with eosin

    Directory of Open Access Journals (Sweden)

    Soad S. Abd El-Hay

    2016-09-01

    Full Text Available A simple and sensitive spectrophotometric method has been established for the determination of clemastine hydrogen fumarate (I, desloratadine (II, losartan potassium(III and moxepril HCl(IV based on binary complex formation with eosin. The method does not involve solvent extraction through the use of a non-ionic surfactant (methylcellulose. The color of the produced complex was measured at 552, 549 nm for (I, (II while was measured at 540 nm for (III and (IV. Appropriate conditions were established for the color reaction between eosin and the studied drugs to obtain maximum sensitivity. Under the proposed conditions, the method is applicable over concentration range of 1.25–11.25, 0.31–2.81, 2.5–20 and 1.25–15 μg/ml for (I, (II, (III and (IV, respectively. The molar absorptivity (ε, sandell sensitivity, detection (LOD and quantitation limits (LOQ are calculated. Unlike other reported ion-pair techniques, the suggested methods have the advantage of being applicable for the determination of the four drugs in their pharmaceutical dosage forms without prior extraction with excellent recoveries.

  1. Molecular dynamic and quantum chemical calculations for phthalazine derivatives as corrosion inhibitors of mild steel in 1 M HCl

    Energy Technology Data Exchange (ETDEWEB)

    Musa, Ahmed Y., E-mail: AMUSA6@UWO.CA [Department of Chemistry, University of Western Ontario, 1151 Richmond Street, London, Ontario, N6A 5B7 (Canada); Department of Chemical and Process Engineering, Universiti Kebangsaan Malaysia, Bangi, 43600 Selangor (Malaysia); Jalgham, Ramzi T.T.; Mohamad, Abu Bakar [Department of Chemical and Process Engineering, Universiti Kebangsaan Malaysia, Bangi, 43600 Selangor (Malaysia)

    2012-03-15

    Highlights: Black-Right-Pointing-Pointer The inhibition of three phthalazine derivatives was studied. Black-Right-Pointing-Pointer The inhibition efficiency increased in the following order: PTD < PT < PTO. Black-Right-Pointing-Pointer The adsorption energies were calculated using molecular dynamics simulations. Black-Right-Pointing-Pointer Quantum chemical parameters were calculated using the AM1, MNDO and PM3 methods. Black-Right-Pointing-Pointer The adsorption of phthalazine derivatives obeys the Langmuir adsorption isotherm. - Abstract: The abilities of phthalazine derivatives, including phthalazine (PT), phthalazone (PTO) and phthalhydrazide (PTD), to inhibit the corrosion of mild steel in 1 M HCl at 30 Degree-Sign C were studied using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements. Theoretical calculations were performed to investigate the electronic structures of the PT derivatives. Our results showed that the inhibition efficiencies of these derivatives improved with increases in concentration. The data also showed that PTD < PT < PTO in terms of the inhibiting efficiency. Theoretical calculations also revealed that PTO is expected to be the best inhibitor among the studied phthalazine derivatives.

  2. Identification and characterization of the HCl-DMS gas phase molecular complex via infrared spectroscopy and electronic structure calculations.

    Science.gov (United States)

    Bork, Nicolai; Du, Lin; Kjaergaard, Henrik G

    2014-02-27

    Models of atmospheric aerosol formation are dependent on accurate Gibbs free binding energies (ΔG°) of gaseous acids and bases, but for most acid–base pairs, only ab initio data are available. We report a combined experimental and theoretical study of the gaseous molecular complex of dimethylsulfide (DMS) and HCl. On the basis of infrared spectroscopy and anharmonic local mode calculations, we determine ΔG(295K)° to be between 6.2 and 11.1 kJ mol(–1). We test the performance of MP2 and five often used DFT functionals with respect to this result. M06-2X performs the best, but also the MP2 prediction is within the experimental range. We find that coupled cluster corrections to the electronic energy improves ΔG° estimates if and only if triple excitations are included. These estimates may be further improved by applying vibrational scaling factors to account for anharmonicity. Hereby, all but the PW91 based predictions are within the experimental range.

  3. The importance of binder moisture content in Metformin HCL high-dose formulations prepared by moist aqueous granulation (MAG

    Directory of Open Access Journals (Sweden)

    Hiroshi Takasaki

    2015-01-01

    Full Text Available The aim of this study was to evaluate binders to improve the flowability of granulates and compactibility of Metformin HCL (Met using the moist aqueous granulation (MAG process. The effect of the binder moisture content on granulate and tablet quality was also evaluated. Vinylpyrrolidone–vinyl acetate copolymer (Kollidon VA64 fine: VA64, polyvidone (Povidone K12: PVP, hydroxypropyl cellulose (HPC SSL SF: HPC and hydroxypropyl methylcellulose (Methocel E5 LV: HPMC were evaluated as binders. These granulates, except for HPMC, had a lower yield pressure than Met active pharmaceutical ingredient (API. HPMC Met was not sufficiently granulated with low water volume. No problems were observed with the VA64 Met granulates during the tableting process. However, HPC Met granulates had a bowl-forming tendency, and PVP Met granulates had the tendency to stick during the tableting process. These bowl-forming and sticking tendencies may have been due to the low moisture absorbency of HPC and the high volume of bound water of PVP, respectively. VA64 Met granulates had the highest ambient moisture content (bulk water, bound water and moisture absorbency. It was concluded that the type of binder used for the Met MAG process has an impact on granulate flow and compactibility, as well as moisture absorbency and maintenance of moisture balance.

  4. Thermodynamic and morphological analysis of eutectic formation of CBZ-L-Asp and L-PheOMe.HCl mixtures

    International Nuclear Information System (INIS)

    Kim, Hyun Jung; Kim, Jong Hoon; Youn, Sung Hun; Shin, Chul Soo

    2006-01-01

    The eutectic melting of a CBZ-L-Asp/L-PheOMe.HCl model mixture was investigated in kinetic, thermal, thermodynamic, rheological, and morphological aspects. From TX-phase diagrams, the eutectic composition was determined to be 0.55 M fraction of CBZ-L-Asp. The highest melting rate and the lowest apparent viscosity in the range of 55-75 deg. C were obtained at the eutectic composition. Using Arrhenius plots of melting rates and apparent viscosities, minimum activation energies in the range of 60-80 deg. C were obtained at the eutectic composition, whereas maximum values were attained below 60 deg. C. At the eutectic composition, the maximum heat of fusion, the lowest excess free energy, and the highest excess entropy values were observed by differential scanning calorimetry (DSC). A highly homogeneous morphology due to rearrangement of molecules was observed in the eutectic mixture via scanning electron microscopy and X-ray diffraction analysis. IR spectra revealed that hydrogen bonding in the mixture increases during eutectic melting

  5. The interfacial capacitance of an oxidised polycrystalline gold electrode in an aqueous HClO4 electrolyte

    International Nuclear Information System (INIS)

    Grdeń, M.

    2013-01-01

    The interfacial capacitance of a polycrystalline gold electrode electrochemically oxidised in an aqueous 0.1 M HClO 4 electrolyte has been investigated by means of the electrochemical impedance spectroscopy. From 1.3 to 3 monolayers of Au atoms were oxidised under constant potential conditions and for various oxidation times. The capacitance of the oxidised layers was analysed as a function of the electrode potential and the extent of the surface oxidation. It was found that the interfacial capacitance decreases upon surface oxidation. The components of the interfacial capacitance of the oxidised layer: the double layer capacitance and the capacitance of the oxidised layer; have been separated. The capacitance of the double layer of the oxidised surface was found to be comparable to the capacitance measured for the metallic surface. - Highlights: • The impedance spectra for thin layers of Au oxides/hydroxides were acquired. • Separate determination of the double layer and the oxide capacitances of oxidised Au • The double layer capacitances of oxidised and non-oxidised Au surfaces are comparable

  6. A kinetic study of the depyritization of oil shale HCl-kerogen concentrate by Thiobacillus ferrooxidans at different temperatures

    Directory of Open Access Journals (Sweden)

    OLGA CVETKOVIC

    2003-05-01

    Full Text Available The results of kinetic studies of bacterial depyritization of HCl-kerogen concentrate of Aleksinac (Serbia oil shale by the chemolithoautotrophic thionic bacteria Thiobacillus ferrooxidans under discontinuous laboratory conditions at various temperatures (0, 20, 28 and 37°C at a pH of ca. 1.5 are presented in this paper. Low pH prevents the occurrence of the precipitation of iron(III-ion hydrolysis products on the substrate particles and thereby reduces the process efficiency. Bacterial depyritization is developed as per kinetics of the first order. The activation energy which points to a successive mechanism of pyrite biooxidation, was computed from the Arrhenius plot. The biochemical kinetics indicators point to a high affinity of the bacteria toward pyrite but small values of Vmax, which are probably the result of decelerated metabolic processes due to the low pH value of the environment resp. the large difference of the pH between the external medium and the cell interior.

  7. Investigations of an excimer laser working with a four-component gaseous mixture He-Kr:Xe-HCl

    Science.gov (United States)

    Iwanejko, Leszek; Pokora, Ludwik J.

    1991-08-01

    The paper presnts working conditions of an XCI excimer laser untypical gas mixture based on KrzXe instead of pure Xe. Such a choice was influenced by the necessity of Findin9 the way to replace imported and expensive Xe by gaseous components accesible in Poland. Determining the range of changes of laser extrnal parameters which enables its proper work with the new gas mixture was the aim of same investigations results of which are presented in this paper. The laser pulse output energy and the pulse duration as a Function of supply voltage and the mixture composition are presented. The range of proper conditions for the laser working with the new mixture He-Kr:Xe--HC1 was determined. The analysis of experimental results showed that using the new mixture ensures value of energy and pulse duration comparable with the ones obtained for the mixture He-''Xe--HCl. Spectral investigations showed the lack of influence of Kr presence in the mixture on the generation spectrum of the laser. L.

  8. Soil Solution

    NARCIS (Netherlands)

    Sonneveld, C.; Voogt, W.

    2009-01-01

    The characteristics of the soil solution in the root environment in the greenhouse industry differ much from those for field grown crops. This is caused firstly by the growing conditions in the greenhouse, which strongly differ from those in the field and secondly the function attributed to the soil

  9. Seeding Solutions

    International Development Research Centre (IDRC) Digital Library (Canada)

    The Crucible Group operates on the basis of good faith –– producing best effort non-consensus texts. ..... science and technology-based solutions to agricultural production constraints, it is ...... In 1997 researchers at Case Western Reserve Medical School in Ohio (US) ...... Is there a need to update the system-wide IP audit?

  10. Circular Solutions

    NARCIS (Netherlands)

    Annevelink, E.; Bos, H.L.; Meesters, K.P.H.; Oever, van den M.J.A.; Haas, de W.; Kuikman, P.J.; Rietra, R.P.J.J.; Sikirica, N.

    2016-01-01

    The fifth part of this report on Circular Solutions is about the circular principle From Waste to Resource. The purpose of this study is to select promising options for the implementation of this circular principle and to elaborate these options further.

  11. Podcast solutions

    CERN Document Server

    Geoghegan, Michael W

    2005-01-01

    Podcasting is the art of recording radio show style audio tracks, then distributing them to listeners on the Web via podcasting software such as iPodder. From downloading podcasts to producing a track for fun or profit, ""Podcast Solutions"" covers the entire world of podcasting with insight, humor, and the unmatched wisdom of experience.

  12. Comparison of hemodynamic effects of lidocaine, prilocaine and mepivacaine solutions without vasoconstrictor in hypertensive patients

    Directory of Open Access Journals (Sweden)

    Bahadir Ezmek

    2010-08-01

    Full Text Available OBJECTIVE: Local anesthetic solutions with vasoconstrictors are not contraindicated in hypertensive patients, but due to their hemodynamic effects, local anesthetics without vasoconstrictors are mainly preferred by the clinicians. The aim of this study was to compare hemodynamic effects of three different local anesthetics without vasoconstrictors during tooth extraction in hypertensive patients. MATERIAL AND METHODS: Sixty-five mandibular molars and premolars were extracted in 60 hypertensive patients (29 females and 31 males; mean age: 66.95 ± 10.87 years; range: 38 to 86 years old. Inferior alveolar and buccal nerve blocks were performed with 2% lidocaine hydrochloride (HCl, 2% prilocaine HCl or 3% mepivacaine HCl without vasoconstrictor. Hemodynamic parameters namely systolic blood pressure (SBP, diastolic blood pressure (DBP, mean arterial pressure (MAP, heart rate (HR, saturation rate (SR, rate pressure product (RPP and pressure rate quotient (PRQ were investigated before and at different intervals after anesthetic injection. RESULTS: The hemodynamic effects of the three agents were similar to each other, although some significance was observed for DBP, MAP, RPP and PRQ values in the lidocaine, prilocaine and mepivacaine groups. CONCLUSION: Lidocaine, prilocaine and mepivacaine solutions without vasoconstrictor can be safely used in hypertensive patients. It is advisable that dental practitioners select anesthetic solutions for hypertensive patients considering their cardiovascular effects in order to provide patient comfort and safety.

  13. Solution Prototype

    DEFF Research Database (Denmark)

    Efeoglu, Arkin; Møller, Charles; Serie, Michel

    2013-01-01

    This paper outlines an artifact building and evaluation proposal. Design Science Research (DSR) studies usually consider encapsulated artifact that have relationships with other artifacts. The solution prototype as a composed artifact demands for a more comprehensive consideration in its systematic...... environment. The solution prototype that is composed from blending product and service prototype has particular impacts on the dualism of DSR’s “Build” and “Evaluate”. Since the mix between product and service prototyping can be varied, there is a demand for a more agile and iterative framework. Van de Ven......’s research framework seems to fit this purpose. Van de Ven allows for an iterative research approach to problem solving with flexible starting point. The research activity is the result between the iteration of two dimensions. This framework focuses on the natural evaluation, particularly on ex...

  14. Excited-state dynamics of a ruthenium(II) catalyst studied by transient photofragmentation in gas phase and transient absorption in solution

    Energy Technology Data Exchange (ETDEWEB)

    Imanbaew, D.; Nosenko, Y. [Fachbereich Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 52–54, 67663 Kaiserslautern (Germany); Forschungszentrum OPTIMAS, Erwin-Schrödinger-Str. 46, 67663 Kaiserslautern (Germany); Kerner, C. [Fachbereich Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 52–54, 67663 Kaiserslautern (Germany); Chevalier, K.; Rupp, F. [Fachbereich Physik, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 46, 67663 Kaiserslautern (Germany); Riehn, C., E-mail: riehn@chemie.uni-kl.de [Fachbereich Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 52–54, 67663 Kaiserslautern (Germany); Forschungszentrum OPTIMAS, Erwin-Schrödinger-Str. 46, 67663 Kaiserslautern (Germany); Thiel, W.R. [Fachbereich Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 52–54, 67663 Kaiserslautern (Germany); Diller, R. [Fachbereich Physik, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 46, 67663 Kaiserslautern (Germany)

    2014-10-17

    Graphical abstract: - Highlights: • Ultrafast dynamics of new Ru(II) catalysts investigated in gas phase and solution. • Catalyst activation (HCl loss) achieved in ion trap by UV photoexcitation. • Electronic relaxation proceeds by IVR and IC followed by ground state dissociation. • No triplet formation in contrast to other Ru-polypyridine complexes. • Solvent prohibits catalyst activation in solution by fast vibrational cooling. - Abstract: We report studies on the excited state dynamics of new ruthenium(II) complexes [(η{sup 6}-cymene)RuCl(apypm)]PF{sub 6} (apypm=2-NR{sub 2}-4-(pyridine-2-yl)-pyrimidine, R=CH{sub 3} (1)/H (2)) which, in their active form [1{sup +}-HCl] and [2{sup +}-HCl], catalyze the transfer hydrogenation of arylalkyl ketones in the absence of a base. The investigations encompass femtosecond pump–probe transient mass spectrometry under isolated conditions and transient absorption spectroscopy in acetonitrile solution, both on the cations [(η{sup 6}-cymene)RuCl(apypm)]{sup +} (1{sup +}, 2{sup +}). Gas phase studies on mass selected ions were performed in an ESI ion trap mass spectrometer by transient photofragmentation, unambiguously proving the formation of the activated catalyst species [1{sup +}-HCl] or [2{sup +}-HCl] after photoexcitation being the only fragmentation channel. The primary excited state dynamics in the gas phase could be fitted to a biexponential decay, yielding time constants of <100 fs and 1–3 ps. Transient absorption spectroscopy performed in acetonitrile solution using femtosecond UV/Vis and IR probe laser pulses revealed additional deactivation processes on longer time scales (∼7–12 ps). However, the formation of the active catalyst species after photoexcitation could not be observed in solution. The results from both studies are compared to former CID investigations and DFT calculations concerning the activation mechanism.

  15. A comment on "Ab initio study: the potential energy curves and ro-vibrational spectrum of low-lying excited states of HCl+ cation"

    Science.gov (United States)

    Liu, Ya-Jun; Cheng, Xin-Lu; Chen, Hua-Jun; Cheng, Jun-Xia; Song, Xiao-Shu

    2018-02-01

    Since the 2Π state in HCl+ is an inverted doublet, the energy of the 2Π1/2 state is higher than the 2Π3/2. Therefore, the larger value of intensity correspond to the transition of 2Π3/2. We calculated the Einstein A coefficients and radiation lifetimes for the A2Σ+-X2Π transition. Our results are in good agreement with the experimental data and theoretical values. Then the ro-vibrational line intensities of the 1-0 band were calculated for the 2Π3/2 and 2Π1/2 states of HCl+. Employing the RKR potential, the predicted band origins for Δν=1-0 are 2569.3 and 2568.55 cm-1 for 2Π3/2 and 2Π1/2, respectively.

  16. Molecular-beam epitaxial growth of insulating AlN on surface-controlled 6H-SiC substrate by HCl gas etching

    International Nuclear Information System (INIS)

    Onojima, Norio; Suda, Jun; Matsunami, Hiroyuki

    2002-01-01

    Insulating AlN layers were grown on surface-controlled 6H-SiC subtrates by molecular-beam epitaxy (MBE) using elemental Al and rf plasma-excited nitrogen (N*). HCl gas etching was introduced as an effective pretreatment method of substrate for MBE growth of AlN. 6H-SiC substrates pretreated by HCl gas etching had no surface polishing scratches and an atomically flat surface. In addition, evident ( 3 √x 3 √)R30 deg. surface reconstruction was observed even before thermal cleaning. AlN layers grown on this substrate had no defects related to surface polishing scratches and excellent insulating characteristics

  17. Gas-particle interactions above a Dutch heathland: I. Surface exchange fluxes of NH3, SO2, HNO3 and HCl

    Directory of Open Access Journals (Sweden)

    E. Nemitz

    2004-01-01

    Full Text Available A field measurement campaign was carried out over a Dutch heathland to investigate the effect of gas-to-particle conversion and ammonium aerosol evaporation on surface/atmosphere fluxes of ammonia and related species. Continuous micrometeorological measurements of the surface exchange of NH3, SO2, HNO3 and HCl were made and are analyzed here with regard to average fluxes, deposition velocities (Vd, canopy resistances (Rc and canopy compensation point for NH3. Gradients of SO2, HNO3 and HCl were measured with a novel wet-denuder system with online anion chromatography. Measurements of HNO3 and HCl indicate an Rc of 100 to 200 s m-1 during warm daytime periods, probably at least partly due to non-zero acid partial pressures above NH4NO3 and NH4Cl on the leaf surfaces. Although it is likely that this observation is exacerbated by the effect of the evaporation of airborne NH4+ on the gradient measurements, the findings nevertheless add to the growing evidence that HNO3 and HCl are not always deposited at the maximum rate. Ammonia (NH3 fluxes show mainly deposition, with some periods of significant daytime emission. The net exchange could be reproduced both with an Rc model (deposition fluxes only using resistance parameterizations from former measurements, as well as with the canopy compensation point model, using parameterizations derived from the measurements. The apoplastic ratio of ammonium and hydrogen concentration (Γs=[NH4+]/[H+] of 1200 estimated from the measurements is large for semi-natural vegetation, but smaller than indicated by previous measurements at this site.

  18. Gas-particle interactions above a Dutch heathland: I. Surface exchange fluxes of NH3, SO2, HNO3 and HCl

    Science.gov (United States)

    Nemitz, E.; Sutton, M. A.; Wyers, G. P.; Jongejan, P. A. C.

    2004-07-01

    A field measurement campaign was carried out over a Dutch heathland to investigate the effect of gas-to-particle conversion and ammonium aerosol evaporation on surface/atmosphere fluxes of ammonia and related species. Continuous micrometeorological measurements of the surface exchange of NH3, SO2, HNO3 and HCl were made and are analyzed here with regard to average fluxes, deposition velocities (Vd), canopy resistances (Rc) and canopy compensation point for NH3. Gradients of SO2, HNO3 and HCl were measured with a novel wet-denuder system with online anion chromatography. Measurements of HNO3 and HCl indicate an Rc of 100 to 200 s m-1 during warm daytime periods, probably at least partly due to non-zero acid partial pressures above NH4NO3 and NH4Cl on the leaf surfaces. Although it is likely that this observation is exacerbated by the effect of the evaporation of airborne NH4+ on the gradient measurements, the findings nevertheless add to the growing evidence that HNO3 and HCl are not always deposited at the maximum rate. Ammonia (NH3) fluxes show mainly deposition, with some periods of significant daytime emission. The net exchange could be reproduced both with an Rc model (deposition fluxes only) using resistance parameterizations from former measurements, as well as with the canopy compensation point model, using parameterizations derived from the measurements. The apoplastic ratio of ammonium and hydrogen concentration (Γs=[NH4+]/[H+]) of 1200 estimated from the measurements is large for semi-natural vegetation, but smaller than indicated by previous measurements at this site.

  19. Maintenance of high HCl/Cly and NOx/NOy in the Antarctic vortex: A chemical signature of confinement during spring

    International Nuclear Information System (INIS)

    Michelsen, H. A.; Webster, C. R.; Manney, G. L.; Scott, D. C.; Margitan, J. J.; May, R. D.; Irion, F. W.; Gunson, M. R.; Russell, J. M. III; Spivakovsky, C. M.

    1999-01-01

    Observations made in the 1994 Antarctic vortex show that Cl y recovered completely into HCl following conversion of Cl y reservoir species to active radicals, and NO x constituted a 4-5 times higher fraction of NO y inside the vortex than outside. Measurements made in October and November from the Airborne Southern Hemisphere Ozone Expedition/Measurements of the Atmospheric Effects of Stratospheric Aircraft (ASHOE/MAESA) ER-2 aircraft mission, the third Atmospheric Laboratory for Applications and Science (ATLAS-3) space shuttle mission, and the Upper Atmosphere Research Satellite (UARS) demonstrate that this unusual partitioning of Cl y and NO y was maintained for at least 4 weeks in the springtime vortex. In response to severe ozone loss, abundances of HCl and NO x remained high despite temperatures low enough to reactivate Cl y and convert NO x to HNO 3 via heterogeneous processes. Thus, under severely ozone depleted conditions, high HCl and NO x abundances in the vortex are maintained until the vortex breaks up or an influx of ozone-rich extravortex air is entrained into the vortex. These observations suggest that the flux of extravortex air entering the core of the lower stratospheric vortex was small or negligible above ∼400 K during late spring, despite weakening of the vortex during this time period. Results of a photochemical model constrained by the measurements suggest that extravortex air entrained into the vortex during October and early November made up less than 5% of the vortex core air at 409 K. The model results also show that heterogeneous chemistry has little effect on the Cl y and NO y partitioning once high abundances of HCl have been attained under ozone depleted conditions, even when aerosol loading is high. (c) 1999 American Geophysical Union

  20. The effect of N-2-cyano-ethylamphetamine. HCl on total lipid contents of placenta and some material and fetal tissues of the rat.

    Science.gov (United States)

    Kulay, L; Oliveira-Filho, R M; Siciliano, S F; Kulay, M N

    1978-12-01

    Female rats received 1.25 mg/kg body weight of N-2-cyano-ethylamphetamine. HCl (Fenproporex chlorhydrate) by oral route, once daily from the 5th to the 21st day of pregnancy, and compared to untreated pregnant rats, showed an increased total lipid content in maternal blood and fetal hearts; liver and heart have had total lipids decrease, while in placenta and fetal livers they were not observed significant differences.

  1. Nqrs Data for C3H2Cl10N2PSb[C3HCl4N2P·Cl6HSb](Subst. No. 0601)

    Science.gov (United States)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C3H2Cl10N2PSb [C3HCl4N2P·Cl6HSb] (Subst. No. 0601)

  2. Influence of the composition of the aqueous phase on the behavior of the system FeCl3-HCl-DPE

    International Nuclear Information System (INIS)

    Ramirez, F. de M.; Jimenez-Reyes, M.

    1981-07-01

    We studied the influence of the aqueous phase composition upon an extraction system in which, at room temperature (20 0 C +- 3 0 C) using the dissolvents FeCl 3 -HCl-di-isopropyl ether the third phase phenomena is present after one minute of agitation. Our results showed that principally the hydrochloric acid dissolvent produced each of the three phases at given concentration levels as well as determined the nature of the chemical composition in each phase. (author)

  3. Quasi-Classical Trajectory Dynamics Study of the Cl(2P) + C2H6 → HCl(v,j) + C2H5 Reaction. Comparison with Experiment.

    Science.gov (United States)

    Espinosa-Garcia, Joaquin; Martinez-Nuñez, Emilio; Rangel, Cipriano

    2018-03-15

    To understand and simulate the dynamics behavior of the title reaction, QCT calculations were performed on a recently developed global analytical potential energy surface, PES-2017. These calculations combine the classical description of the dynamics with pseudoquantization in the reactants and products to perform a theoretical/experimental comparison on the same footing. Thus, in the products a series of constraints are included to analyze the HCl(v = 0,j) product, which is experimentally detected. At collision energies of 5.5 and 6.7 kcal mol -1 the largest fraction of available energy is deposited as translation, 67%, while the ethyl radical shows significant internal energy, 27%, and so it does not act as a spectator of the reaction, thus reproducing recent experimental evidence. The HCl(v=0, j) rotational distribution is cold, peaking at j = 2, only one unit hotter than experiment, which represents an error of 0.12 kcal mol -1 . At a collision energy of 5.5 kcal mol -1 product translational distribution is slightly hotter than experiment, but at 6.7 kcal mol -1 agreement with recent experiments is practically quantitative, suggesting that the first experiments should be revised. In addition, we observe that the HCl(v=0, j) scattering distribution shifts from isotropic at low values of j to backward at high values of j, which is in agreement with experimental data. Finally, no evidence was found for the "chattering" mechanism suggested to explain the low translational energy of the HCl product in the backward scattering region. In sum, agreement with experiments of a series of sensible dynamic properties permits us to be optimistic on the quality and accuracy of the theoretical tools used in the present work, QCT and PES-2017.

  4. Simultaneous HPLC Determination of Chlordiazepoxide and Mebeverine HCl in the Presence of Their Degradation Products and Impurities

    Directory of Open Access Journals (Sweden)

    Rania N. El-Shaheny

    2015-01-01

    Full Text Available A simple, rapid, and sensitive RP-HPLC method was developed and validated for the simultaneous determination of chlordiazepoxide (CDO and mebeverine HCl (MBV in the presence of CDO impurity (2-amino-5-chlorobenzophenone, ACB and MBV degradation product (veratric acid, VER. Separation was achieved within 9 min on a BDS Hypersil phenyl column (4.5 mm × 250 mm, 5 µm particle size using a mobile phase consisting of acetonitrile: 0.1 M potassium dihydrogen phosphate: triethylamine (35 : 65 : 0.2, v/v/v in an isocratic mode at a flow rate of 1 mL/min. The pH of the mobile phase was adjusted to 4.5 with orthophosphoric acid and UV detection was set at 260 nm. A complete validation procedure was conducted. The proposed method exhibited excellent linearity over the concentration ranges of 1.0–100.0, 10.0–200.0, 2.0–40.0, and 2.0–40.0 µg/mL for CDO, MBV, VER, and ACB, respectively. The proposed method was applied for the simultaneous determination of CDO and MBV in their coformulated tablets with mean percentage recoveries of 99.75 ± 0.62 and 98.61 ± 0.38, respectively. The results of the proposed method were favorably compared with those of a comparison HPLC method using Student t-test and the variance ratio F-test. The chemical structure of MBV degradation product was ascertained by mass spectrometry and IR studies.

  5. Hydrophilic interaction liquid chromatography in analysis of granisetron HCl and its related substances. Retention mechanisms and method development.

    Science.gov (United States)

    Maksić, Jelena; Tumpa, Anja; Stajić, Ana; Jovanović, Marko; Rakić, Tijana; Jančić-Stojanović, Biljana

    2016-05-10

    In this paper separation of granisetron and its two related substances in HILIC mode is presented. Separation was done on silica column derivatized with sulfoalkylbetaine groups (ZIC-HILIC). Firstly, retention mechanisms were assessed whereby retention factors of substances were followed in wide range of acetonitrile content (80-97%), at constant concentration of aqueous buffer (10mM) as well as at constant pH value of 3.0. Further, in order to developed optimal HILIC method, Design of Experiments (DoE) methodology was applied. For optimization full factorial design 3(2) was employed. Influence of acetonitrile content and ammonium acetate concentration were investigated while pH of the water phase was kept at 3.3. Adequacy of obtained mathematical models was confirmed by ANOVA. Optimization goals (α>1.15 and minimal run time) were accomplished with 94.7% of acetonitrile in mobile phase and 70 mM of ammonium acetate in water phase. Optimal point was in the middle of defined Design Space. In the next phase, robustness was experimetally tested by Rechtschaffen design. The investigated factors and their levels were: acetonitrile content (±1%), ammonium acetate molarity in water phase (±2 mM), pH value of water phase (±0.2) and column temperature (±4 °C). The validation scope included selectivity, linearity, accuracy and precision as well as determination of limit of detection (LOD) and limit of quantification (LOQ) for the related substances. Additionally, the validation acceptance criteria were met in all cases. Finally, the proposed method could be successfully utilized for estimation of granisetron HCl and its related substances in tablets and parenteral dosage forms, as well as for monitoring degradation under various stress conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Formulation, release characteristics, and bioavailability study of gastroretentive floating matrix tablet and floating raft system of Mebeverine HCl.

    Science.gov (United States)

    El Nabarawi, Mohamed A; Teaima, Mahmoud H; Abd El-Monem, Rehab A; El Nabarawy, Nagla A; Gaber, Dalia A

    2017-01-01

    To prolong the residence time of dosage forms within the gastrointestinal tract until all drug is released at the desired rate is one of the real challenges for oral controlled-release drug delivery systems. This study was designed to develop a controlled-release floating matrix tablet and floating raft system of Mebeverine HCl (MbH) and evaluate different excipients for their floating behavior and in vitro controlled-release profiles. Oral pharmacokinetics of the optimum matrix tablet, raft system formula, and marketed Duspatalin ® 200 mg retard as reference were studied in beagle dogs. The optimized tablet formula (FT-10) and raft system formula (FRS-11) were found to float within 34±5 sec and 15±7 sec, respectively, and both remain buoyant over a period of 12 h in simulated gastric fluid. FT-10 (Compritol/HPMC K100M 1:1) showed the slowest drug release among all prepared tablet formulations, releasing about 80.2% of MbH over 8 h. In contrast, FRS-11 (Sodium alginate 3%/HPMC K100M 1%/Precirol 2%) had the greatest retardation, providing sustained release of 82.1% within 8 h. Compared with the marketed MbH product, the C max of FT-10 was almost the same, while FRS-11 maximum concentration was higher. The t max was 3.33, 2.167, and 3.0 h for marketed MbH product, FT-10, and FRS-11, respectively. In addition, the oral bioavailability experiment showed that the relative bioavailability of the MbH was 104.76 and 116.01% after oral administration of FT-10 and FRS-11, respectively, compared to marketed product. These results demonstrated that both controlled-released floating matrix tablet and raft system would be promising gastroretentive delivery systems for prolonging drug action.

  7. Innovation of novel 'Tab in Tab' system for release modulation of milnacipran HCl: optimization, formulation and in vitro investigations.

    Science.gov (United States)

    Parejiya, Punit B; Barot, Bhavesh S; Patel, Hetal K; Shelat, Pragna K; Shukla, Arunkumar

    2013-11-01

    The study was aimed toward development of modified release oral drug delivery system for highly water soluble drug, Milnacipran HCl (MH). Novel Tablet in Tablet system (TITs) comprising immediate and extended release dose of MH in different parts was fabricated. The outer shell was composed of admixture of MH, lactose and novel herbal disintegrant obtained from seeds of Lepidium sativum. In the inner core, MH was matrixed with blend of hydrophilic (Benecel®) and hydrophobic (Compritol®) polymers. 3² full factorial design and an artificial neuron network (ANN) were employed for correlating effect of independent variables on dependent variables. The TITs were characterized for pharmacopoeial specifications, in vitro drug release, SEM, drug release kinetics and FTIR study. The release pattern of MH from batch A10 containing 25.17% w/w Benecel® and 8.21% w/w of Compritol® exhibited drug release pattern close proximal to the ideal theoretical profile (t(50%) = 5.92 h, t(75%) = 11.9 h, t(90%) = 18.11 h). The phenomenon of drug release was further explained by concept of percolation and the role of Benecel® and Compritol® in drug release retardation was studied. The normalized error obtained from ANN was less, compared with the multiple regression analysis, and exhibits the higher accuracy in prediction. The results of short-term stability study revealed stable chataracteristics of TITs. SEM study of TITs at different dissolution time points confirmed both diffusion and erosion mechanisms to be operative during drug release from the batch A10. Novel TITs can be a succesful once a day delivery system for highly water soluble drugs.

  8. Performance of new 400-MHz HTS power-driven magnet NMR technology on typical pharmaceutical API, cinacalcet HCl.

    Science.gov (United States)

    Silva Elipe, Maria Victoria; Donovan, Neil; Krull, Robert; Pooke, Donald; Colson, Kimberly L

    2018-04-17

    After years towards higher field strength magnets, nuclear magnetic resonance (NMR) technology in commercial instruments in the past decade has expanded at low and high magnetic fields to take advantage of new opportunities. At lower field strengths, permanent magnets are well established, whereas for midrange and high field, developments utilize superconducting magnets cooled with cryogenic liquids. Recently, the desire to locate NMR spectrometers in nontypical NMR laboratories has created interest in the development of cryogen-free magnets. These magnets require no cryogenic maintenance, eliminating routine filling and large cryogen dewars in the facility. Risks of spontaneous quenches and safety concerns when working with cryogenic liquids are eliminated. The highest field commercially available cryogen-free NMR magnet previously reported was at 4.7 T in 2013. Here we tested a prototype cryogen-free 9.4-T power-driven high-temperature-superconducting (HTS) magnet mated to commercial NMR spectrometer electronics. We chose cinacalcet HCl, a typical active pharmaceutical ingredient, to evaluate its performance towards structure elucidation. Satisfactory standard 1D and 2D homonuclear and heteronuclear NMR results were obtained and compared with those from a standard 9.4-T cryogenically cooled superconducting NMR instrument. The results were similar between both systems with minor differences. Further comparison with different shims and probes in the HTS magnet system confirmed that the magnet homogeneity profile could be matched with commercially available NMR equipment for optimal results. We conclude that HTS magnet technology works well providing results comparable with those of standard instruments, leading us to investigate additional applications for this magnet technology outside a traditional NMR facility. Copyright © 2018 John Wiley & Sons, Ltd.

  9. Effect of oral coadministration of drugs on the disposition of (14C)-celiprolol HCl in rats

    International Nuclear Information System (INIS)

    Town, C.; Knipe, J.; Taft, C.; Tantillo, N.; Klunk, L.; Grebow, P.

    1986-01-01

    Celiprolol HCL (C) is a cardioselective β-blocker undergoing clinical trials as an antihypertensive agent. Studies with rats indicated that the oral coadministration of 2.5 mg/kg of chlorthalidone (CT) caused a 40% decrease in the urinary excretion of radioactivity from a 40 mg/kg dose of ( 14 C)-C(C). In order to further understand the nature of this interaction, groups of 6 rats were given 40 mg/kg of (C) alone and, one week later,/sub R.(C) pluse the drug to be tested. The vehicle was 0.5% Methocel. After each dosing, urine was collected for 96 hours from each rat and the amount of total radioactivity excreted was compared between treatments. The results showed that oral coadministration of 2.5 mg/kg hydrochlorothiazide, 2.5 mg/kg furosemide, 2.5 mg/kg indapamide, 5.0 mg/kg cimetidine, 10.0 mg/kg theophylline, and 1.0 mg/kg digoxin were without effect on the disposition of orally administered (C). Conversely, 2.5 mg/kg CT, 2.5 mg/kg acetazolamide (AZ) and 5.0 mg/kg hydralazine (H) caused a significant (p < 0.05) decrease in the urinary excretio of orally administered (C). CT and AZ are both potent inhibitors of carbonic anhydrase and their action on this enzyme may cause the effect on the disposition of (C). The action of H may be due to its pharmacologic action and warrants further study

  10. Pilot-plant for NOx, SO2, HCl removal from flue-gas of municipal waste incinerator by electron beam irradiation

    International Nuclear Information System (INIS)

    Doi, Takeshi; Suda, Shoichi; Morishige, Atsushi; Tokunaga, Okihiro; Aoki, Yasushi; Sato, Shoichi; Komiya, Mikihisa; Hashimoto, Nobuo; Nakajima, Michihiro.

    1992-01-01

    A pilot-Plant for NO x , SO 2 and HCl removal from flue-gas of municipal waste incinerator by electron beam irradiation was designed and its construction at Matsudo City Waste Disposal Center was planned. The flue-gas of 1,000 Nm 3 /hr is guided from the waste incinerator flue-gas line of 30,000 Nm 3 /hr to the Pilot-Plant to be processed by spraying Ca(OH) 2 slurry (NKK-LIMAR Process) and irradiating high-energy electron beam of an accelerator. NO x , SO 2 and HCl are removed simultaneously from the flue-gas by the enhanced reaction with Ca(OH) 2 under irradiation. According to the basic research performed using a small size reactor at TRCRE of JAERI, the electron beam irradiation process was proved to be very effective for these harmful gases removal. Based on this result, the Pilot-Plant was designed for the demonstration of NO x , SO 2 and HCl removal performance using electron accelerator of maximum energy 0.95 MeV and maximum power 15 kW. The designing and planning were promoted by NKK in cooperation with JAERI and Matsudo City. (author)

  11. Use of cationites for separation of transplutonium elements from other elements from aqueous and aqua-alcohol solutions of hydrochloric and nitric acids

    International Nuclear Information System (INIS)

    Guseva, L.I.; Tikhomirova, G.S.

    1984-01-01

    The behaviour of Am, Cm, Pu and certain fragment elements (Cs, Sr, Y, Zr, Nb, Ru, Eu) on cationite dauex-50 in aqueous and aqueous-alcohol solutions of HCl and HNO 3 has been studied. Dependences of distribution coefficients and separation factors of the elements on the acid concentration and alcohol content in the solutions are presented. The sorption of TPE by cationite from HCl and HNO 3 solutions in the presence of alcohol is shown to increase over the range of concentrations studied (from 0.5 mol/L to 4-5 mol/L), which is explained by the salting-out effect of alcohol. The distribution coefficients of TPE in the solutions, containing >= 50% alcohol, constitute >= 10 2 . The distribution coefficients of the fragment elements in the presence of alcohol also increase, but to a considerably lesser extent, which results in a better separation. The study of the washing-out curves has shown that, to separate TPE from fragment elements on cationites, both HCl and HNO 3 solutions can be used, at that, in the case of aqueous solutions a better separation is attained at acid concentration, equal to 1 mol/L, and in the case of eluating by aqueous-alcohol solutions a good separation is achieved at hig-her concentrations of the acids as well

  12. Comparison of the carcinogenic effectiveness in mouse skin of methyl- and ethylnitrosourea, nitrosourethane and nitrosonitro-guanidine and the effect of deuterium labeling

    International Nuclear Information System (INIS)

    Lijinsky, W.

    1982-01-01

    The carcinogenic activities of a number of directly acting methylating and ethylating agents have been compared by mouse skin painting in acetone solution. Nitrosomethylurethane and nitrosoethylurethane failed to induce tumors after greater than 60 weeks treatment. Nitrosomethylurea was somewhat more effective than nitrosoethylurea, as measured by the longer latent period than nitrosoethylurea, as measured Nitrosomethylnitroguanidine, by the same measure, was a weaker carcinogen than nitrosoethylnitroguanidine at both dose levels used (0.02 M and 0.008 M); the latter compound was the most potent skin carcinogen of those examined. There was no significant difference in carcinogenic effectiveness when the alkyl group of the nitrosoureas or the nitronitrosoguanidines contained deuterium instead of hydrogen, which supports the concept that alkylation of cellular macromolecules by the intact alkyl group is responsible for carcinogenesis by these compounds

  13. Synthesis and Characterization of TiO2(B Nanotubes Prepared by Hydrothermal Method Using [Ti8O12(H2O24]Cl8.HCl.7H2O as Precursor

    Directory of Open Access Journals (Sweden)

    Hari Sutrisno

    2010-04-01

    Full Text Available Low-dimension TiO2-related material has been synthesized by hydrothermal treatment of [Ti8O12(H2O24]Cl8.HCl.7H2O crystal as precursor in a 10 M NaOh aqueous solution at 150 C for 24 h. Characterization of the obtained product was carried out by a range of techniques including X-ray diffraction (XRD, high resolution scanning electron microscopy (HRSEM, high resolution transmission electron microscopy (HRTEM, Raman spectroscopy and nitrogen adsorption-desorption isotherm (Brunauer-Emmett-Teller (BET-Barret-Joyner-Halender (BJH. From HRTEM, XRD and Raman spectra showed that the obtained product has a TiO2(B structure. According to HRTEM observations, it was found that TiO2(B has nanotubular structure with approximately 5-8 nm in outer and 3-6 nm in inner diameter. The BET surface area of TiO2(B nanotubes is quiet large, values of 418.3163 m2/g being obtained. Pore structure analyisis by the BJH method showed that the average pore diameter of TiO2(B nanotubes has 5.5781 nm.

  14. Heterogeneous kinetics of H2O, HNO3 and HCl on HNO3 hydrates (α-NAT, β-NAT, NAD) in the range 175-200 K

    Science.gov (United States)

    Iannarelli, Riccardo; Rossi, Michel J.

    2016-09-01

    standard heats of evaporation ΔHev0 of H2O and HNO3 for α- and β-NAT, respectively, led to an estimate for the relative standard enthalpy difference between α- and β-NAT of -6.0 ± 20 kJ mol-1 in favor of β-NAT, as expected, despite a significantly larger value of Eev for HNO3 in α-NAT. This in turn implies a substantial activation energy for HNO3 accommodation in α- compared to β-NAT where Eacc(HNO3) is essentially zero. The kinetic (α(HCl), Jev(HCl)) and thermodynamic (Peq(HCl)) parameters of HCl-doped α- and β-NAT have been determined under the assumption that HCl adsorption did not significantly affect α(H2O) and α(HNO3) as well as the evaporation flux Jev(H2O). Jev(HCl) and Peq(HCl) on both α- and β-NAT are larger than the corresponding values for HNO3 across the investigated temperature range but significantly smaller than the values for pure H2O ice at T < 200 K.

  15. Corrosion Behaviour of Sn-based Lead-Free Solders in Acidic Solution

    Science.gov (United States)

    Nordarina, J.; Mohd, H. Z.; Ahmad, A. M.; Muhammad, F. M. N.

    2018-03-01

    The corrosion properties of Sn-9(5Al-Zn), Sn-Cu and SAC305 were studied via potentiodynamic polarization method in an acidic solution of 1 M hydrochloric acid (HCl). Sn-9(5Al-Zn) produced different polarization profile compared with Sn-Cu and SAC305. The morphological analysis showed that small, deep grooves shaped of corrosion product formed on top of Sn-9(5Al-Zn) solder while two distinctive structures of closely packed and loosely packed corrosion product formed on top of Sn-Cu and SAC305 solder alloys. Phase analysis revealed the formations of various corrosion products such as SnO and SnO2 mainly dominant on surface of solder alloys after potentiodynamic polarization in 1 M hydrochloric acid (HCl).

  16. Adsorption and inhibitive properties of sildenafil (Viagra) for zinc in hydrochloric acid solution

    Science.gov (United States)

    Fouda, A. S.; Ibrahim, H.; Atef, M.

    Sildenafil (Viagra) was investigated as corrosion inhibitor for Zn in 1 M HCl solution using chemical and electrochemical methods at 25 °C. Electrochemical results showed that this drug is efficient inhibitor for Zn in HCl and the inhibition efficiency (IE) reached to 91% at 300 ppm. The IE increases with the drug concentration and decreases with increasing temperature. The adsorption of this drug on Zn surface follows Langmuir adsorption isotherm. The polarization plots revealed that Sildenafil acts as a mixed-type inhibitor. The thermodynamic parameters of activation and adsorption were calculated and discussed. The surface morphology of the Zn specimens was evaluated using scanning electron microscope (SEM), energy dispersive X-ray (EDX), atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR) techniques.

  17. Comparison of the analgesic efficacy of dexketoprofen trometamol and meperidine HCl in the relief of renal colic.

    Science.gov (United States)

    Ay, Mehmet Oguzhan; Sebe, Ahmet; Kozaci, Nalan; Satar, Salim; Acikalin, Ayca; Gulen, Muge; Acehan, Selen

    2014-01-01

    In this study, the analgesic effects of dexketoprofen trometamol and meperidine hydrochloride were compared in patients diagnosed with renal colic. This study was a prospective, randomized, double-blind study. Fifty-two patients, between the ages of 18 and 70 years who were diagnosed with renal colic, were enrolled in the study after obtaining ethics committee approval. Before drug injection, dexketoprofen trometamol and meperidine hydrochloride were placed in closed envelopes, and the patients were randomly given a single dose of intravenous infusion for 20 minutes. Severity of pain and symptoms was evaluated with the numerical rating scale and renal colic symptom score for each patient immediately before administration of drugs and 30 minutes after the end of the application. At the same time, systolic arterial blood pressure, diastolic arterial pressure, respiratory rate, heart rate, nausea, vomiting, and reactions due to drug administration were recorded before and after drug administration. In statistical methods, t test, analysis of variance, and repeated measure analysis were used for the analysis of normally distributed continuous variables and the Mann-Whitney U, Kruskal-Wallis and Friedman tests were used for analysis of not-normally distributed continuous variables. In the analysis of discrete variables, the χ test was used. In both groups, a significant decrease was found in numerical rating scale values measured 30 minutes after drug administration, but the decline in dexketoprofen trometamol group (P = 0.02) was found to be more. Although a significant decrease was found in the renal colic symptom score (P dexketoprofen trometamol group, no significant decrease was found in the meperidine HCl (P = 0.058) group. After drug administration, a statistically significant decrease was found in the systolic arterial blood pressure, heart rate, and respiratory rate in both groups. Also, a statistically significant decrease was found in the diastolic arterial

  18. Probing the interactions of bromchlorbuterol-HCl and phenylethanolamine A with HSA by multi-spectroscopic and molecular docking technique

    International Nuclear Information System (INIS)

    Bi, Shuyun; Zhao, Tingting; Zhou, Huifeng; Wang, Yu; Li, Zhihong

    2016-01-01

    Highlights: • Molecular docking showed that BCB/PEA was bound at sub-domain IIA of HSA. • Fluorescence lifetimes indicated that the quenching was a static quenching. • CD spectra showed that BCB/PEA changed the conformation of HSA. • The competitive binding between site markers and BCB/PEA was studied. • The mutual influence on the two drugs binding HSA was studied. - Abstract: Using fluorescence quenching, fluorescence lifetime, (UV + vis) absorption, circular dichroism (CD) and molecular docking technique, the interactions of human serum albumin (HSA) with bromchlorbuterol-HCl (BCB) and phenylethanolamine A (PEA) were investigated. The quenching rate constants and binding constants for BCB/PEA with HSA were determined at T = (292.15, 302.15 and 312.15) K respectively, which were all decreased with the increase of the temperature, showing not a dynamic quenching. The fluorescence lifetime of HSA with BCB/PEA had changed little compared to that of HSA alone (τ_0), further confirming that BCB/PEA quenching of intrinsic fluorescence of HSA is a static quenching. The effects of K"+, Ca"2"+, Cu"2"+, Zn"2"+ and Fe"3"+ on the binding were studied. The analysis of the thermodynamic parameters for BCB/(PEA + HSA) showed that BCB/PEA could bind to HSA via hydrophobic force. The binding distances were determined as 2.90 and 4.11 nm for (BCB + HSA) and (PEA + HSA) based on the Förster’s non-radiative energy transfer theory (FRET). Synchronous fluorescence and CD spectra indicated that the conformation of HSA was changed by BCB/PEA. The competitive studies for the drug with site marker suggested that both BCB and PEA were bound at Sudlow’s sites I (sub-domain IIA, also known as indometacin binding site) in HSA, and the results of the study of molecular docking also leads to the same conclusion. The competitive binding experiments for the two drugs were also performed, which further indicates that PEA and BCB could share the same binding site, and PEA has a much

  19. Combined experimental and numerical kinetic characterization of NR vulcanized with sulphur, N terbutyl, 2 benzothiazylsulphenamide and N,N diphenyl guanidine

    Energy Technology Data Exchange (ETDEWEB)

    Milani, G., E-mail: gabriele.milani@polimi.it [Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan (Italy); Hanel, T.; Donetti, R. [Pirelli Tyre, Via Alberto e Piero Pirelli 25, 20126 Milan (Italy); Milani, F. [Chem. Co, Via J.F.Kennedy 2, 45030 Occhiobello (Italy)

    2016-06-08

    The paper presents the final results of a comprehensive experimental and numerical analysis aimed at deeply investigating the behavior of Natural Rubber (NR) vulcanized with sulphur in presence of different accelerators during standard rheometer tests. NR in presence of sulphur and two different accelerators (DPG and TBBS) in various concentrations is investigated, changing the curing temperature in the range 150-180°C and obtaining rheometer curves with a step of 10°C. Sulphur-TBBS concentrations considered are 1-1, 1-3, 3-3 and 3-1, with DPG at 1-4 phr respectively. A total of 48 experimental rheometer curves is so obtained. To fit experimental data, the general reaction scheme proposed by Han and co-workers for vulcanized sulphur NR is re-adapted and suitably modified taking into account the single contributions of the different accelerators. Chain reactions initiated by the formation of macro-compounds responsible for the formation of the unmatured crosslinked polymer are accounted for. In presence of two accelerators, reactions are assumed to proceed in parallel, making the practically effective hypothesis that there is no interaction between the two accelerators. From the simplified kinetic scheme adopted, a closed form solution is found for the crosslink density, with the only limitation that the induction period is excluded from computations. For each experimented case on the same blend, reaction kinetic constants provided by the model are utilized to deduce their trend in the Arrhenius space, also outside the temperature range inspected. Rather close linearity is found in the majority of the cases. A comparative analysis is carefully conducted among the constants at the different concentrations of S, TBBS and DPG investigated, allowing a prediction of curing behavior at any vulcanization temperature and with concentrations not experimentally tested, without the need of addition costly experimentation.

  20. Combined experimental and numerical kinetic characterization of NR vulcanized with sulphur, N terbutyl, 2 benzothiazylsulphenamide and N,N diphenyl guanidine

    International Nuclear Information System (INIS)

    Milani, G.; Hanel, T.; Donetti, R.; Milani, F.

    2016-01-01

    The paper presents the final results of a comprehensive experimental and numerical analysis aimed at deeply investigating the behavior of Natural Rubber (NR) vulcanized with sulphur in presence of different accelerators during standard rheometer tests. NR in presence of sulphur and two different accelerators (DPG and TBBS) in various concentrations is investigated, changing the curing temperature in the range 150-180°C and obtaining rheometer curves with a step of 10°C. Sulphur-TBBS concentrations considered are 1-1, 1-3, 3-3 and 3-1, with DPG at 1-4 phr respectively. A total of 48 experimental rheometer curves is so obtained. To fit experimental data, the general reaction scheme proposed by Han and co-workers for vulcanized sulphur NR is re-adapted and suitably modified taking into account the single contributions of the different accelerators. Chain reactions initiated by the formation of macro-compounds responsible for the formation of the unmatured crosslinked polymer are accounted for. In presence of two accelerators, reactions are assumed to proceed in parallel, making the practically effective hypothesis that there is no interaction between the two accelerators. From the simplified kinetic scheme adopted, a closed form solution is found for the crosslink density, with the only limitation that the induction period is excluded from computations. For each experimented case on the same blend, reaction kinetic constants provided by the model are utilized to deduce their trend in the Arrhenius space, also outside the temperature range inspected. Rather close linearity is found in the majority of the cases. A comparative analysis is carefully conducted among the constants at the different concentrations of S, TBBS and DPG investigated, allowing a prediction of curing behavior at any vulcanization temperature and with concentrations not experimentally tested, without the need of addition costly experimentation.

  1. On the stabilization of NbV-solutions by ZrIV and HfIV

    International Nuclear Information System (INIS)

    Soerensen, E.; Bjerre, A.B.

    1987-11-01

    Niobium cannot be separated from zirconium or hafnium when these elements occur together in solution with common anions such as Cl- and SO 4 --. This is ascribed to the copolymerisation of Nb v and the hydrolyzed ionic species of Zr IV v and Hf IV by which the colloidal particles are masked as Zr- and Hf-compounds. In HCl the particles are positively charged as opposed to when they are in sulphate solution where the Zr- and Hf- sulphate complexes confer a negative charge. The two cases are considered separately. (author)

  2. Studies on removal of plutonium from oxalic acid containing hydrochloric acid solutions

    Energy Technology Data Exchange (ETDEWEB)

    Ghadse, D R; Noronha, D M; Joshi, A R [Fuel Chemistry Division, Bhabha Atomic Research Centre, Mumbai (India)

    1994-06-01

    Solution containing hydrochloric acid, oxalic acid and considerable quantities of plutonium may be generated while recycling of scrap produced during the metallic fuel fabrication. Plutonium from such waste is normally recovered by anion exchange method after the destruction of oxalic acid using suitable oxidising agent. Solvent extraction and ion exchange methods are being explored in this laboratory for recovery of Pu from oxalic acid containing HCl solutions without prior destruction of oxalic acid. This paper describes the results on the determination of distribution ratios for extraction of Pu(IV) from hydrochloric acid using Aliquot-336 or HDEHP under varying experimental conditions. (author). 5 refs., 5 tabs.

  3. Studying titanium-molybdenum-zirconium alloys of increased corrosion resistance in acid solutions

    International Nuclear Information System (INIS)

    Tomashov, N.D.; Kazarin, V.I.; Mikheev, V.S.; Goncharenko, B.A.; Sigalovskaya, T.M.; Kalyanova, M.P.

    1977-01-01

    New promising Ti-Mo-Nb-Zr system alloys, possessing good workability and a high corrosion resistance in non-oxidizing solutions of acids, have been developed. The alloys may be recommended as structural materials for equipment operating in severely agressive acid media, such as hydrochloric, sulphuric and phosphoric acids. The corrosion resistance of alloys of the above system in solutions of H 2 SO 4 , HCl and H 3 PO 4 acids may be maximized by increasing the overall alloying to 42% (keeping the ratio of the alloying components Mo/Nb/Zr=4/1/1 unchanged), while retaining sufficiently good plasticity and workability

  4. Monitoring corrosion and corrosion control of iron in HCl by non-ionic surfactants of the TRITON-X series - Part II. Temperature effect, activation energies and thermodynamics of adsorption

    International Nuclear Information System (INIS)

    Amin, Mohammed A.; Ahmed, M.A.; Arida, H.A.; Arslan, Taner; Saracoglu, Murat; Kandemirli, Fatma

    2011-01-01

    Research highlights: → TX-305 exhibits inhibiting properties for iron corrosion more than TX-165 and TX 100. → Inhibition efficiency increases with temperature, suggesting chemical adsorption. → The three tested surfactants act as mixed-type inhibitors with cathodic predominance. → Validation of corrosion rates measured by Tafel extrapolation method is confirmed. - Abstract: The inhibition characteristics of non-ionic surfactants of the TRITON-X series, namely TRITON-X-100 (TX-100), TRITON-X-165 (TX-165) and TRITON-X-305 (TX-305), on the corrosion of iron was studied in 1.0 M HCl solutions as a function of inhibitor concentration (0.005-0.075 g L -1 ) and solution temperature (278-338 K). Measurements were conducted based on Tafel extrapolation method. Electrochemical frequency modulation (EFM), a non-destructive corrosion measurement technique that can directly give values of corrosion current without prior knowledge of Tafel constants, is also presented. Experimental corrosion rates determined by the Tafel extrapolation method were compared with corrosion rates obtained by the EFM technique and an independent method of chemical analysis. The chemical method of confirmation of the corrosion rates involved determination of the dissolved cation, using ICP-AES (inductively coupled plasma atomic emission spectrometry). The aim was to confirm validation of corrosion rates measured by the Tafel extrapolation method. Results obtained showed that, in all cases, the inhibition efficiency increased with increase in temperature, suggesting that chemical adsorption occurs. The adsorptive behaviour of the three surfactants followed Temkin-type isotherm. The standard free energies of adsorption decreased with temperature, reflecting better inhibition performance. These findings confirm chemisorption of the tested inhibitors. Thermodynamic activation functions of the dissolution process were also calculated as a function of each inhibitor concentration. All the results

  5. Acoustic and volumetric properties of betaine hydrochloride drug in aqueous D(+)-glucose and sucrose solutions

    International Nuclear Information System (INIS)

    Ryshetti, Suresh; Gupta, Akash; Tangeda, Savitha Jyostna; Gardas, Ramesh L.

    2014-01-01

    Highlights: • Density and speed of sound are measured for B.HCl drug in aq. D(+)-glucose and sucrose. • Solvation behavior of B.HCl drug studied in aqueous D(+)-glucose and sucrose. • Cosphere overlap model is used to understand the transfer partial molar volume. • Hepler’s constant indicated structure making ability of B.HCl drug in studied systems. - Abstract: The densities (ρ) and speeds of sound (u) of betaine hydrochloride (B.HCl) drug (0.01 to 0.06) mol · kg −1 in (0.10, 0.20 and 0.30) mol · kg −1 aqueous D(+)-glucose and sucrose solutions are reported as a function of temperature at T = (293.15 to 313.15) K and atmospheric pressure. The values of density (ρ) and speed of sound (u) are obtained with high precision. These values have been used to estimate the apparent molar volume (V 2,ϕ ), partial molar volume (V 2 ∞ ), transfer partial molar volume (Δ t V 2 ∞ ), apparent molar isentropic compressibility (K s,2,ϕ ), partial molar isentropic compressibility (K s,2 ∞ ), transfer partial molar compressibility (Δ t K s,2 ∞ ), hydration number (N H ), partial molar expansion (E 2 ∞ ) and Hepler’s constant (∂ 2 V 2 ∞ /∂T 2 ) P . Furthermore, pair (V AB and K AB ) and triplet (V ABB and K ABB ) interaction coefficients have been computed from the values of Δ t V 2 ∞ and Δ t K s,2 ∞ . The co-sphere overlap model is used to understand the values of Δ t V 2 ∞ and Δ t K s,2 ∞ . The positive values of (∂ 2 V 2 ∞ /∂T 2 ) P indicate structure making ability of betaine hydrochloride in aqueous D(+)-glucose and sucrose solutions at the temperatures and compositions investigated

  6. Behaviour of trivalent actinides and lanthanide elements in chloride solution; Comportement des lanthanides et transuraniens trivalents en milieu chlorhydrique

    Energy Technology Data Exchange (ETDEWEB)

    Marin, B [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1969-07-01

    The aim of this work is to compare the complexation in chloride solutions of trivalent lanthanides and actinides. We have first studied the solvatation of these cations without complexation. We found a difference between Am, Cm and Rare Earths (we can separate lanthanides into Light and Heavy Rare Earths). For studying the complexation we choose the technic of electrophoresis on paper after establishing a simple theory of mobilities in complex solutions. The hydrolysis of these cations was studied and compared in chloride solutions. We have then studied the complexation with the Cl{sup -} ligand in some solutions: HCl, NH{sub 4}Cl, CaCl{sub 2}, CeCl{sub 3}, LiCl. We have established that the complexation is the same in dilute HCl solutions but in concentrated solutions the trivalent actinides are more complexed. This difference is sharper in LiCl solutions. We also proposed the different models of complex in these solutions. (author) [French] Le but de ce travail est de comparer les transuraniens et lanthanides trivalents au point de vue de leur complexation en solution chlorhydrique. Nous avons ete amenes tout d'abord a etudier la solvatation de ces cations non complexes. C'est ainsi que nous pouvons constater une difference entre Am, Cm et les lanthanides. Ces derniers pouvant se separer en lanthanides legers et lanthanides lourds. Pour etudier la complexation nous avons utilise l'electrophorese sur papier apres avoir donne une theorie simple des mobilites en milieu complexant. Apres avoir etudie et compare l'hydrolyse de ces divers cations en solution chlorhydrique, nous avons etudie leur complexation avec l'ion Cl{sup -} dans dans divers milieux: HCl, NH{sub 4}Cl, CaCl{sub 2}, CeCl{sub 3}, LiCl. ous avons note qu'en solution HCl les deux series se comportent de la meme facon pour des concentrations faibles en Cl{sup -} mais que les transuraniens se complexent plus fortement dans les solutions concentrees. Cette difference s'accroit encore dans les milieux

  7. Spectrographic determination of strontium in yttrium-90 solutions; Determinacion espectrografica de estroncio en soluciones de itrio-90

    Energy Technology Data Exchange (ETDEWEB)

    Roca, M; Capdevila, C

    1970-07-01

    The copper spark method has been used for determining strontium in the concentration range 1-100 g/ml in yttrium-90 solutions containing 0,5 % or thereabouts of ammonium citrate. The influence of the citric acid as well as the ammonium citrate with regard to 2N HCL solutions has been studied: the citric acid enhances the line intensities of strontium. The employment of either barium or lanthanum as reference element compensates for this enhancement. Because of the increase in sensitivity mentioned above, the study of influence of the citric acid has been extended and several impurities usually determined in radioisotope solutions have been considered. (Author) 4 refs.

  8. Effect of chloride ions on the corrosion behavior of low-alloy steel containing copper and antimony in sulfuric acid solution

    Science.gov (United States)

    Park, Sun-Ah; Kim, Seon-Hong; Yoo, Yun-Ha; Kim, Jung-Gu

    2015-05-01

    The influence of the addition of HCl on the corrosion behavior of low-alloy steel containing copper and antimony was investigated using electrochemical (potentiodynamic and potentiostatic polarization tests, and electrochemical impedance spectroscopy) and weight loss tests in a 1.6M H2SO4 solution with different concentrations of hydrochloric acid (0.00, 0.08, 0.15 and 0.20 M HCl) at 60 °C. The result showed that the corrosion rate decreased with increasing HCl by the formation of protective layers. SEM, EDS and XPS examinations of the corroded surfaces after the immersion test indicated that the corrosion production layer formed in the solution containing HCl was highly comprised of metallic Cu, Cu chloride and metallic (Fe, Cu, Sb) compounds. The corrosion resistance was improved by the Cu-enriched layer, in which chloride ions are an accelerator for cupric ion reduction during copper deposition. Furthermore, cuprous and antimonious chloride species are complex salts for cuprous ions adsorbed on the surface during copper deposition.

  9. Recovery of copper and cyanide from waste cyanide solutions using emulsion liquid membrane with LIX 7950 as the carrier.

    Science.gov (United States)

    Xie, Feng; Wang, Wei

    2017-08-01

    The feasibility of using emulsion liquid membranes (ELMs) with the guanidine extractant LIX 7950 as the mobile carrier for detoxifying copper-containing waste cyanide solutions has been determined. Relatively stable ELMs can be maintained under suitable stirring speed during mixing ELMs and the external solution. Effective extraction of copper cyanides by ELMs only occurs at pH below 11. High copper concentration in the external phase and high volume ratio of the external phase to ELMs result in high transport rates of copper and cyanide. High molar ratio of cyanide to copper tends to suppress copper extraction. The presence of thiocyanate ion significantly depresses the transport of copper and cyanide through the membrane while the thiosulfate ion produces less impact on copper removal by ELMs. Zinc and nickel cyanides can also be effectively extracted by ELMs. More than 90% copper and cyanide can be effectively removed from alkaline cyanide solutions by ELMs under suitable experimental conditions, indicating the effectiveness of using the designed ELM for recovering copper and cyanide from waste cyanide solutions.

  10. Facile synthesis of dendritic Cu by electroless reaction of Cu-Al alloys in multiphase solution

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ying; Liang, Shuhua, E-mail: liangxaut@gmail.com; Yang, Qing; Wang, Xianhui

    2016-11-30

    Highlights: • Nano- or micro-scale fractal dendritic copper (FDC) was synthesized by electroless immersing of Cu-Al alloys in CuCl{sub 2} + HCl. • FDC size increases with the increase of Al content in Cu-Al alloys immersed in CuCl{sub 2} + HCl solution. • Nanoscale Cu{sub 2}O was found at the edge of FDC. Nanoporous copper (NPC) can also be obtained by using Cu{sub 17}Al{sub 83} alloy. • The potential difference between CuAl{sub 2} and α-Al phase and the replacement reaction in multiphase solution are key factors. - Abstract: Two-dimensional nano- or micro-scale fractal dendritic coppers (FDCs) were synthesized by electroless immersing of Cu-Al alloys in hydrochloric acid solution containing copper chloride without any assistance of template or surfactant. The FDC size increases with the increase of Al content in Cu-Al alloys immersed in CuCl{sub 2} + HCl solution. Compared to Cu{sub 40}Al{sub 60} and Cu{sub 45}Al{sub 55} alloys, the FDC shows hierarchical distribution and homogeneous structures using Cu{sub 17}Al{sub 83} alloy as the starting alloy. The growth direction of the FDC is <110>, and all angles between the trunks and branches are 60°. Nanoscale Cu{sub 2}O was found at the edge of FDC. Interestingly, nanoporous copper (NPC) can also be obtained through Cu{sub 17}Al{sub 83} alloy. Studies showed that the formation of FDC depended on two key factors: the potential difference between CuAl{sub 2} intermetallic and α-Al phase of dual-phase Cu-Al alloys; a replacement reaction that usually occurs in multiphase solution. The electrochemical experiment further proved that the multi-branch dendritic structure is very beneficial to the proton transfer in the process of catalyzing methanol.

  11. Cementation of the solid radioactive waste with polymer-cement solutions using the method of impregnation

    International Nuclear Information System (INIS)

    Gorbunova, O.

    2015-01-01

    Cementation of solid radioactive waste (SRW), i.e. inclusion of solid radioactive waste into cement matrix without cavities - is one of the main technological processes used for conditioning low and intermediate level radioactive waste. At FSUE 'Radon' the industrialized method of impregnation has been developed and since 2003 has been using for cementation of solid radioactive waste. The technology is that the polymer-cement solution, having high penetrating properties, is supplied under pressure through a tube to the bottom of the container in which solid radioactive waste has preliminarily been placed. The polymer-cement solution is evenly moving upwards through the channels between the particles of solid radioactive waste, fills the voids in the bulk volume of the waste and hardens, forming a cement compound, the amount of which is equal to the original volume. The aim of the investigation was a selection of a cement solution suitable for SRW impregnation (including fine particles) without solution depletion and bottom layers stuffing. It has been chosen a polymer: PHMG (polyhexamethylene-guanidine), which is a stabilizing and water-retaining component of the cement solution. The experiments confirm that the polymer increases the permeability of the cement solution by a 2-2.5 factor, the viscosity by a 1.2 factor, the stability of the consistency by a 1.5-1.7 factor, and extends the operating range of the W/C ratio to 0.5-1.1. So it is possible to penetrate a volume of SRW bigger by a 1.5-2.0 factor. It has been proved, that PHMG polymer increases strength and frost-resistance of the final compounds by a 1.8-2.7 factor, and contributes to fast strength development at the beginning of hardening and it decreases Cs-137 leashing rate by a 1.5-2 factor

  12. Olive (Olea europaea) leaf methanolic extract prevents HCl/ethanol-induced gastritis in rats by attenuating inflammation and augmenting antioxidant enzyme activities.

    Science.gov (United States)

    Al-Quraishy, Saleh; Othman, Mohamed S; Dkhil, Mohamed A; Abdel Moneim, Ahmed Esmat

    2017-07-01

    Gastritis is preponderantly characterized by inflammation of the lining epithelial layer and the chronic gastritis is considered as a pre-cancer lesion. For many centuries olive (Olea europaea) leaf has been used for its putative health potential, nonetheless, to date, the gastroprotective effects of olive leaves have not been studied yet. Hence, in this study we investigated whether olive leaf extract (OLE) could protect gastric mucosa against HCl/ethanol-induced gastric mucosal damage in rats. Hcl/ethanol administration caused significant damage to the gastric mucosa, as confirmed by gastric ulcer index and histological evaluation. However, this damage was largely prevented by pre-administering 20mg/kg omeprazole or 100mg/kg OLE. Interestingly, the damage was completely prevented by pre-administering 200 and 300mg/kg OLE. Moreover, OLE attenuated the inflammatory response by decreasing nuclear factor-κB (NF-κB), cycloxygenase-2 (COX-2) and tumor necrosis factor-α (TNF-α) expressions, and down-regulating inducible nitric oxide synthase (iNOS) and interleukin-1β (IL-1β) in gastric mucosa. The gastroprotective mechanism of OLE involved the promotion of enzymatic and nonenzymatic molecules (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glutathione reduced form), promoting nuclear factor erythroid 2-related factor 2 (Nrf2) mRNA expression, halting lipid peroxidation and preventing the overproduction of nitric oxide. Together, our findings clearly demonstrated that OLE could prevent HCl/ethanol-induced gastritis by attenuating inflammation and oxidant/antioxidant imbalance. Indeed, OLE could potentially be useful as a natural therapy for gastritis. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  13. Unimolecular HCl and HF elimination reactions of 1,2-dichloroethane, 1,2-difluoroethane, and 1,2-chlorofluoroethane: assignment of threshold energies.

    Science.gov (United States)

    Duncan, Juliana R; Solaka, Sarah A; Setser, D W; Holmes, Bert E

    2010-01-21

    The recombination of CH(2)Cl and CH(2)F radicals generates vibrationally excited CH(2)ClCH(2)Cl, CH(2)FCH(2)F, and CH(2)ClCH(2)F molecules with about 90 kcal mol(-1) of energy in a room temperature bath gas. New experimental data for CH(2)ClCH(2)F have been obtained that are combined with previously published studies for C(2)H(4)Cl(2) and C(2)H(4)F(2) to define reliable rate constants of 3.0 x 10(8) (C(2)H(4)F(2)), 2.4 x 10(8) (C(2)H(4)Cl(2)), and 1.9 x 10(8) (CH(2)ClCH(2)F) s(-1) for HCl and HF elimination. The product branching ratio for CH(2)ClCH(2)F is approximately 1. These experimental rate constants are compared to calculated statistical rate constants (RRKM) to assign threshold energies for HF and HCl elimination. The calculated rate constants are based on transition-state models obtained from calculations of electronic structures; the energy levels of the asymmetric, hindered, internal rotation were directly included in the state counting to obtain a more realistic measure for the density of internal states for the molecules. The assigned threshold energies for C(2)H(4)F(2) and C(2)H(4)Cl(2) are both 63 +/- 2 kcal mol(-1). The threshold energies for CH(2)ClCH(2)F are 65 +/- 2 (HCl) and 63 +/- 2 (HF) kcal mol(-1). These threshold energies are 5-7 kcal mol(-1) higher than the corresponding values for C(2)H(5)Cl or C(2)H(5)F, and beta-substitution of F or Cl atoms raises threshold energies for HF or HCl elimination reactions. The treatment presented here for obtaining the densities of states and the entropy of activation from models with asymmetric internal rotations with high barriers can be used to judge the validity of using a symmetric internal-rotor approximation for other cases. Finally, threshold energies for the 1,2-fluorochloroethanes are compared to those of the 1,1-fluorochloroethanes to illustrate substituent effects on the relative energies of the isomeric transition states.

  14. Study on HCl Driving Force for the Reaction of NaCl-Maleic Acid Mixing Single Droplet Using Micro-FTIR Spectroscopy

    Science.gov (United States)

    He, Xiang; Zhang, Yunhong

    2016-04-01

    Chemical aging is the one of the most important physicochemical process in atmospheric aerosols. Mixing of sea salt and water-soluble organic components has profound effects on the volatile characteristic and evolving chemical composition of the anthropogenic origin aerosols, which are poorly understood. In this study, the chemical reaction behavior of the mixture of NaCl and maleic acid (H2MA) micron-level single droplet was investigated using a gas-flow system combined with microscopic Fourier transform infrared (micro-FTIR) spectrometer over the range of relative humidity (63˜95% RH) for the first time. The results showed that the mixture of NaCl and H2MA single droplet could react to form monosodium maleate salt (NaHMA) at the constant RH from the characterization of the FTIR. The reaction is a result of an acid displacement reaction R1, which is driven by high volatility of the HCl product. NaCl(aq)+H2MA(aq)=NaHMA(aq)+HCl(aq,g) (R1) According to the change tendency of the absorbance values of 1579 cm-1 COO- stretching band of the NaHMA dependent upon reaction times at different RHs, the growth range of the trend which could lead to the faster reaction rate was obvious at lower RH. The water content of the droplet was also more likely to reduce rapidly with the loss of the RH from the absorbance changes of 3400 cm-1H2O stretching band dependent upon reaction times. These may be due to irreversible evaporation of HCl gas which is the main driving force for this type of reaction and the NaHMA is a less hygroscopic component compared to H2MA. And the HCl gas is more likely to evaporate faster from the single droplet and promote the reaction rate and the consumption of water content at lower RH. These results could help in understanding the chemical conversion processes of water-soluble dicarboxylic acids to dicarboxylate salts, as well as the consumption of Cl in sea salt aerosols by organic acids in the atmosphere.

  15. Formulation of a modified release metformin. HCl matrix tablet: influence of some hydrophilic polymers on release rate and in-vitro evaluation

    Directory of Open Access Journals (Sweden)

    John Rojas

    2011-09-01

    Full Text Available Metformin hydrochloride is an antidiabetic agent which improves glucose tolerance in patients with type 2 diabetes and reduces basal plasma levels of glucose. In this study, a simplex centroid experimental design with 69 runs was used to select the best combination of some hydrophilic polymers that rendered a 24 h in-vitro release profile of metformin.HCl. The Korsmeyer-Peppas model was used to model the dissolution profiles since it presented the best fit to the experimental data. Further, a cubic model predicted the best formulation of metformin.HCl containing polyvinyl pyrrolidone, ethyl cellulose, hydroxypropyl methyl cellulose, carrageenan, sodium alginate, and gum arabic at 6.26, 68.7, 6.26, 6.26, 6.26 and 6.26 % levels, respectively. The validation runs confirmed the accuracy of the cubic model with six components for predicting the best set of components which rendered a once-a-day modified release hydrophilic matrix tablet in compliance with the USP specifications.O cloridrato de metformina é um agente antidiabético que melhora a tolerância à glicose em pacientes com diabetes tipo 2 e reduz os níveis plasmáticos basais de glicose. Neste estudo, um projeto experimental do tipo "centróide simplex" com 69 tomadas foi usado para selecionar a melhor combinação de alguns polímeros hidrofílicos que gerou um perfil de liberação da metformina.HCl de 24 horas. O modelo Korsmeyer-Peppas foi usado para modelar os perfis de dissolução, uma vez que apresentou os melhores ajustes aos dados experimentais. Além disso, um modelo cúbico previu a melhor formulação de metformina.HCl sendo aquela contendo polivinilpirrolidona, etilcelulose, hidroxipropilmetil celulose, carragena, alginato de sódio e goma arábica nos níveis 6.26, 68.7, 6.26, 6.26, 6.26 e 6.26 %, respectivamente. As corridas de validação confirmaram a precisão do modelo cúbico com os seis componentes para prever o melhor conjunto de componentes que originou uma

  16. A Chemical Activation Study of the Unimolecular Reactions of CD3CD2CHCl2 and CHCl2CHCl2 with Analysis of the 1,1-HCl Elimination Pathway.

    Science.gov (United States)

    Larkin, Allie C; Nestler, Matthew J; Smith, Caleb A; Heard, George L; Setser, Donald W; Holmes, Bert E

    2016-10-03

    Chemically activated C2D5CHCl2 molecules were generated with 88 kcal mol-1 of vibrational energy by the recombination of C2D5 and CHCl2 radicals in a room temperature bath gas. The competing 2,1-DCl and 1,1-HCl unimolecular reactions were identified by the observation of the CD3CD=CHCl and CD3CD=CDCl products. The initial CD3CD2C-Cl carbene product from 1,1-HCl elimination rearranges to CD3CD=CDCl under the conditions of the experiments. The experimental rate constants were 2.7 x107 and 0.47 x107 s-1 for 2,1-DCl and 1,1-HCl elimination reactions, respectively, which corresponds to branching fractions of 0.84 and 0.16. The experimental rate constants were compared to calculated statistical rate constants to assign threshold energies of 54 and ≈ 66 kcal mol-1 for the 1,2-DCl and 1,1-HCl reactions, respectively. The statistical rate constants were obtained from models developed from electronic-structure calculations for the molecule and its transition states. The rate constant (5.3 x 107 s-1) for the unimolecular decomposition of CHCl2CHCl2 molecules formed with 82 kcal mol-1 of vibrational energy by the recombination of CHCl2 radicals also is reported. Based upon the magnitude of the calculated rate constant, 1,1-HCl elimination must contribute less than 15% to the reaction; 1,2-HCl elimination is the major reaction and the threshold energy is 59 kcal mol-1. Calculations also were done to analyze previously published rate constants for chemically activated CD2Cl-CHCl2 molecules with 86 kcal mol-1 of energy in order to obtain a better overall description of the nature of the 1,1-HCl pathway for 1,1-dichloroalkanes. The interplay of the threshold energies for the 2,1-HCl and 1,1-HCl reactions and the available energy determines the product branching fractions for individual molecules. The unusual nature of the transition state for 1,1-HCl elimination is discussed.

  17. Sorption of Pb(II) from aqueous solution by konjac glucomannan beads

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Konjac glucomannan beads have been investigated as metal biosorbent for Pb(II) from aqueous solu-tions. The effect of contact time, solution pH, initial metal concentration, and desorption were studied in batch experiments at 20℃±2℃. Maximum mental sorption was found to occur at initial pH 4.0―5.5. Kinetic studies revealed that the initial uptake was rapid and equilibrium was established in 3 h and that the data followed the prseudo-second order reaction. The equilibrium sorption data at initial pH 4.0 were described by the Langmuir and Freundlich isotherm models; however, Langmuir isotherm model has been found to provide the best correlation. The highest value of Langmuir maximum uptake (qmax) was found to be 105.71 mg·g-1. Similar Freundlich empirical constant (KF) was obtained to be 1.98 for lead. Adsorption-complexation may be involved in the sorption process of lead. Desorption experi- ments showed evidence that after two contacts neither HCl nor EDTA solutions were able to desorb lead from the konjac glucomannan beads, but the desorbtion efficacy of HCl solution was higher than EDTA solution. The results obtained show that konjac glucomannan beads may be used for the treat-ment of wastewater contaminated with lead.

  18. Partial molar volume of paracetamol in water, 0.1 M HCl and 0.154 M NaCl at T = (298.15, 303.15, 308.15 and 310.65) K and at 101.325 kPa

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, Muhammad Javed [Department of Chemistry, Quaid-i-Azam University, Islamabad, Capital 54320 (Pakistan)]. E-mail: mjiqauchem@yahoo.com; Malik, Qaisar Mahmood [Department of Chemistry, Quaid-i-Azam University, Islamabad, Capital 54320 (Pakistan)]. E-mail: qaisar_@hotmail.com

    2005-12-15

    The apparent molar volume of paracetamol (4-acetamidophenol) in water, 0.1 M HCl and 0.154 M NaCl as solvents at (298.15, 303.15, 308.15 and 310.65) K temperatures and at a pressure of 101.325 kPa were determined from the density data obtained with the help of a vibrating-tube Anton Paar DMA-48 densimeter. The partial molar volume, V {sub m}, of paracetamol in these solvents at different temperatures was evaluated by extrapolating the apparent molar volume versus molality plots to m = 0. In addition, the partial molar expansivity, E {sup .}, the isobaric coefficient of thermal expansion, {alpha} {sub p}, and the interaction coefficient, S {sub v}, have also been computed. The expansivity data show dependence of E {sup .} values on the structure of the solute molecules.

  19. Partial molar volume of paracetamol in water, 0.1 M HCl and 0.154 M NaCl at T = (298.15, 303.15, 308.15 and 310.65) K and at 101.325 kPa

    International Nuclear Information System (INIS)

    Iqbal, Muhammad Javed; Malik, Qaisar Mahmood

    2005-01-01

    The apparent molar volume of paracetamol (4-acetamidophenol) in water, 0.1 M HCl and 0.154 M NaCl as solvents at (298.15, 303.15, 308.15 and 310.65) K temperatures and at a pressure of 101.325 kPa were determined from the density data obtained with the help of a vibrating-tube Anton Paar DMA-48 densimeter. The partial molar volume, V m , of paracetamol in these solvents at different temperatures was evaluated by extrapolating the apparent molar volume versus molality plots to m = 0. In addition, the partial molar expansivity, E . , the isobaric coefficient of thermal expansion, α p , and the interaction coefficient, S v , have also been computed. The expansivity data show dependence of E . values on the structure of the solute molecules

  20. Thermodynamic modeling of ternary and quaternary (liquid + liquid) systems containing water, FeCl3, HCl and diisopropyl ether

    NARCIS (Netherlands)

    Milosevic, M.; Hendriks, I.; Smits, R.E.R.; Schuur, B.; Haan, de A.B.

    2013-01-01

    Liquid–liquid extraction using ethers as solvents is a potentially energy saving alternative for the concentration of aqueous ferric chloride solutions. Adequate thermodynamic models that describe the behavior of the resulting quaternary systems (FeCl3, ether, acid and water) are not available in