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Sample records for hydrochloric acid auth

  1. Hydrochloric acid recycling from chlorinated hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Sowieja, D. [Sulzer Escher Wyss GmbH, Ravensburg (Germany); Schaub, M. [Sulzer Chemtech Ltd., Winterthur (Switzerland)

    1993-12-31

    Chlorinated hydrocarbons present a major ecological hazard since most of them are only poorly biodegradable. Incineration is an economical process for their destruction, however the usually recovered sodium or calcium chlorides do not present a value and their disposal may even be very costly. Recovery of hydrochloric acid may therefore present an economical solution, mainly were large quantities of highly chlorinated compounds can be processed (author) 6 refs., 4 figs., 1 tab.

  2. Hydrochloric acid for treating metabolic alkalosis.

    Science.gov (United States)

    Korkmaz, A; Yildirim, E; Aras, N; Ercan, F

    1989-09-01

    Six patients with severe metabolic alkalosis were treated with intravenous hydrochloric acid (HCl) infusion. HCl was given through a central venous catheter, at a concentration of 0.1 mEq per ml. At least two of the following criteria were considered for initiation of the therapy: An arterial pH of greater than 7.45, a base excess (BE) of greater than +7 mmol/L, a PaCO2 of greater than 50 mmHg. The HCl amount was calculated using the BE formula, however, two thirds was infused for avoiding excessive acid loading. Patients were monitored by the blood gases, serum electrolytes, hemoglobin, hematocrit, bilirubin determinations and blood smear findings. While a significant decrease was noticed in pH and BE values, moderate changes were detected in PaCO2 due to different ventilatory status of the cases. All laboratory test results remained within normal limits and no complication was encountered. The advantage of the therapy is that less volume is needed for the correction of alkalosis, particularly in the cases requiring fluid restriction. HCl therapy, moreover, is a safe and time-saving method because of having rapid response to the treatment in the critically ill surgical patients.

  3. HYDROXYLAMMONIUM [ON 111 AQUEOUS HYDROCHLORIC ACID

    African Journals Online (AJOL)

    octacyanomolybdateiv) anion by hydroxylammonium ion has been studied in aqueous hydrochloric ... of substrates have been investigated in aqueous solution (1-7). The results of ... (4) and nitrogen was identified as described previously (8).

  4. An unusual presentation of hydrochloric acid ingestion: a mystery unraveled.

    Science.gov (United States)

    Ganapathy, Vinod Prabhu; Das, Rashmi Ranjan; Chinnakkannan, Selvakumar; Panda, Shasanka Shekhar

    2015-03-01

    Unintentional acid ingestion is less commonly encountered than alkali ingestion. The injury develops for hours to days after ingestion and often results in progressively increasing difficulty in airway management. However, gastric perforation is rare. A 3-year-old boy presented to us with an orotonsillopharyngeal membrane and severe upper airway obstruction. Subsequently, he was diagnosed with a case of gastric perforation due to unintentional hydrochloric acid ingestion. He was treated with partial gastrectomy and feeding jejunostomy, and the recovery was good. Unintentional hydrochloric acid ingestion is rare in children. The manifestations masquerade many other clinical conditions, and the diagnosis is difficult in cases in which history of ingestion is not available. Treatment is symptomatic, and emergency surgery is indicated in case of gastrointestinal perforation.

  5. Kinetic study of free fatty acid esterification reaction catalyzed by recoverable and reusable hydrochloric acid.

    Science.gov (United States)

    Su, Chia-Hung

    2013-02-01

    The catalytic performance and recoverability of several homogeneous acid catalysts (hydrochloric, sulfuric, and nitric acids) for the esterification of enzyme-hydrolyzed free fatty acid (FFA) and methanol were studied. Although all tested catalysts drove the reaction to a high yield, hydrochloric acid was the only catalyst that could be considerably recovered and reused. The kinetics of the esterification reaction catalyzed by hydrochloric acid was investigated under varying catalyst loading (0.1-1M), reaction temperature (303-343K), and methanol/FFA molar ratio (1:1-20:1). In addition, a pseudo-homogeneous kinetic model incorporating the above factors was developed. A good agreement (r(2)=0.98) between the experimental and calculated data was obtained, thus proving the reliability of the model. Furthermore, the reusability of hydrochloric acid in FFA esterification can be predicted by the developed model. The recoverable hydrochloric acid achieved high yields of FFA esterification within five times of reuse.

  6. Accidental intoxication with hydrochloric acid and hydrofluoric acid mixture

    Directory of Open Access Journals (Sweden)

    Anna Smędra-Kaźmirska

    2014-08-01

    Full Text Available The paper describes a fatal case of accidental ingestion of a mixture of hydrochloric acid and hydrofluoric acid. The man was admitted to hospital, where appropriate treatment, adequate to his condition, was instituted. Numerous ventricular fibrillation episodes, for which the patient was defibrillated repeatedly, were observed during the period of hospitalization. The patient was in a critical condition, with progressive symptoms of hypovolemic shock and multiorgan failure. On the next day after admission, signs of electromechanical dissociation progressing to asystole were noted. The instituted resuscitation procedure proved ineffective and the patient died. Autopsy revealed brownish discoloration of the esophageal, gastric, and small intestinal mucous membranes. Numerous ulcerations without signs of perforation were found both in the esophagus and in the stomach. The mucous membrane of the small intestine demonstrated focal rubefactions, whereas no focal lesions of the large intestinal mucosa were seen. Microscopic investigation of the biopsy specimens collected from the stomach, duodenum and small intestine revealed mucous membrane necrosis foci, reaching the deeper layers of the wall of these organs. The mucous membrane of the large intestine was congested. Bioptates obtained from the lungs indicated the presence of hemorrhagic infarcts and focal extravasations. Poisoning with the aforementioned acids with consequent necrosis of the esophageal, gastric, duodenal and small intestinal walls with hemorrhages to the gastrointestinal tract, as well as extravasations and hemorrhagic infarcts in the lungs was considered to be the cause of death.

  7. Accidental intoxication with hydrochloric acid and hydrofluoric acid mixture.

    Science.gov (United States)

    Smędra-Kaźmirska, A; Kędzierski, M; Barzdo, M; Jurczyk, Ap; Szram, S; Berent, J

    2014-01-01

    The paper describes a fatal case of accidental ingestion of a mixture of hydrochloric acid and hydrofluoric acid. The man was admitted to hospital, where appropriate treatment, adequate to his condition, was instituted. Numerous ventricular fibrillation episodes, for which the patient was defibrillated repeatedly, were observed during the period of hospitalization. The patient was in a critical condition, with progressive symptoms of hypovolemic shock and multiorgan failure. On the next day after admission, signs of electromechanical dissociation progressing to asystole were noted. The instituted resuscitation procedure proved ineffective and the patient died. Autopsy revealed brownish discoloration of the esophageal, gastric, and small intestinal mucous membranes. Numerous ulcerations without signs of perforation were found both in the esophagus and in the stomach. The mucous membrane of the small intestine demonstrated focal rubefactions, whereas no focal lesions of the large intestinal mucosa were seen. Microscopic investigation of the biopsy specimens collected from the stomach, duodenum and small intestine revealed mucous membrane necrosis foci, reaching the deeper layers of the wall of these organs. The mucous membrane of the large intestine was congested. Bioptates obtained from the lungs indicated the presence of hemorrhagic infarcts and focal extravasations. Poisoning with the aforementioned acids with consequent necrosis of the esophageal, gastric, duodenal and small intestinal walls with hemorrhages to the gastrointestinal tract, as well as extravasations and hemorrhagic infarcts in the lungs was considered to be the cause of death.

  8. Laboratory investigation of three distinct emissions monitors for hydrochloric acid.

    Science.gov (United States)

    Dene, Charles E; Pisano, John T; Durbin, Thomas D; Bumiller, Kurt; Crabbe, Keith; Muzio, Lawrence J

    2016-12-01

    The measurement of hydrochloric acid (HCl) on a continuous basis in coal-fired plants is expected to become more important if HCl standards become implemented as part of the Federal Mercury and Air Toxics Standards (MATS) standards that are under consideration. For this study, the operational performance of three methods/instruments, including tunable diode laser absorption spectroscopy (TDLAS), cavity ring down spectroscopy (CRDS), and Fourier transform infrared (FTIR) spectroscopy, were evaluated over a range of real-world operating environments. Evaluations were done over an HCl concentration range of 0-25 ppmv and temperatures of 25, 100, and 185 °C. The average differences with respect to temperature were 3.0% for the TDL for values over 2.0 ppmv and 6.9% of all concentrations, 3.3% for the CRDS, and 4.5% for the FTIR. Interference tests for H2O, SO2, and CO, CO2, and NO for a range of concentrations typical of flue gases from coal-fired power plants did not show any strong interferences. The possible exception was an interference from H2O with the FTIR. The instrument average precision over the entire range was 4.4% for the TDL with better precision seen for concentrations levels of 2.0 ppmv and above, 2.5% for the CRDS, and 3.5% for the FTIR. The minimum detection limits were all on the order of 0.25 ppmv, or less, utilizing the TDL values with a 5-m path. Zero drift was found to be 1.48% for the TDL, 0.88% for the CRDS, and 1.28% for the FTIR. This study provides an evaluation of the operational performance of three methods/instruments, including TDL absorption spectroscopy (TDLAS), cavity ring down spectroscopy (CRDS), and FTIR spectroscopy, for the measurement of hydrochloric acid (HCl) over a range of real-world operating environments. The results showed good instrument accuracy as a function of temperature and no strong interferences for flue gases typical to coal-fired power plants. The results show that these instruments would be viable for the

  9. Comparison between phosphoric acid and hydrochloric acid in microabrasion technique for the treatment of dental fluorosis

    OpenAIRE

    Mahshid Mohammadi Bassir; Golnaz Bagheri

    2013-01-01

    Purpose: To compare the effectiveness of phosphoric acid (H 3 PO 4 )-pumice compound with conventional hydrochloric acid (HCl)-pumice compound in treating different severities of dental fluorosis with the microabrasion technique. Materials and Methods: Sixty-seven anterior teeth from seven patients with different severities of dental fluorosis were treated. In each patient, half of the teeth were treated with HCl-pumice compound and the other half with H 3 PO 4 -pumice compound (split-mou...

  10. Camphor Sulfonic Acid-hydrochloric Acid Codoped Polyaniline/polyvinyl Alcohol Composite: Synthesis and Characterization

    OpenAIRE

    Jorge Enrique Osorio-Fuente; Carlos Gómez-Yáñez; María de los Ángeles Hernández-Pérez; Fidel Pérez-Moreno

    2014-01-01

    A complementary dopant system formed by hydrochloric and camphor sulfonic (CSA) acids was used in the in-situ synthesis of a polyaniline (PANi)/polyvinyl alcohol (PVA) composite. The conductivity measurements showed that the use of CSA either as single dopant or codopant caused a decrement up to 2 orders of magnitude on the overall conductivity as well as an improvement on thermal stability. The PANi/PVA composites were characterized by spectroscopic and thermal analysis. Conducting emeraldin...

  11. Selenium dioxide catalysed oxidation of acetic acid hydrazide by bromate in aqueous hydrochloric acid medium

    Indian Academy of Sciences (India)

    R S Yalgudre; G S Gokavi

    2012-07-01

    Selenium dioxide catalysed acetic acid hydrazide oxidation by bromate was studied in hydrochloric acid medium. The order in oxidant concentration, substrate and catalyst were found to be unity. Increasing hydrogen ion concentration increases the rate of the reaction due to protonation equilibria of the oxidant. The mechanism of the reaction involves prior complex formation between the catalyst and substrate, hydrazide, followed by its oxidation by diprotonated bromate in a slow step. Acetic acid was found to be the oxidation product. Other kinetic data like effect of solvent polarity and ionic strength on the reaction support the proposed mechanism.

  12. Superficial performance and pore structure of palygorskite treated by hydrochloric acid

    Institute of Scientific and Technical Information of China (English)

    LIU Yi-xin; DAI Wei-wei; Wang Ting; TAO Yong

    2006-01-01

    In order to amend the superficial performance of palygorskite and improve its application, the natural palygorskite(NP) was treated in the dipping and ionic exchanging experiments using 6 mol/L hydrochloric acid treatment. The performance and pore structure of the treated palygorskite(TP) were investigated by means of microscope analyses, FT-IR, XRF, BET-SSA and full hole distribution analytical techniques. The results show that the hydrochloric acid treatment can make the gracile and aggregating compact crystal bundles inside palygorskite clay broken and dispersed, the roughness of microcrystalline surface increases, which not only can dissolve or remove dolomite but vary the superficial performance of palygorskite to some degree. The specific surface area and pore volume increase a lot, while the mean pore size decreases. The pore structure of TP changes remarkably compared with that of NP after 6 mol/L hydrochloric acid treatment, and the relevant physicochemical performance can be improved.

  13. Extraction of Alumina from high-silica bauxite by hydrochloric acid leaching using preliminary roasting method

    Science.gov (United States)

    Valeev, D. V.; Mansurova, E. R.; Bychinskii, V. A.; Chudnenko, K. V.

    2016-02-01

    A process of dissolution Severoonezhsk deposit boehmite-kaolinite bauxite by hydrochloric acid, as well as the processes that occur during open-air calcination, were investigated. A dehydration process has been studied, and the basic phase transformation temperatures were identified. Temperature and time of calcination influence on bauxite dehydration speed were determined. It is shown that the preliminary calcination increases the extraction ratio of alumina into solution up to 89%. Thermodynamic modelling of physical and chemical processes of bauxite decomposition by hydrochloric acid and the basic forms of aluminium speciation in solution were obtained.

  14. Extraction Mechanism of La3+ from Hydrochloric Acid Solution Using Cyanex 302

    Institute of Scientific and Technical Information of China (English)

    乌东北; 牛春吉; 李德谦

    2004-01-01

    The solvent extraction of La3+ from hydrochloric acid solutions was investigated using bis(2, 4, 4-trimethylpentyl) monothiophosphinic acid(Cyanex 302, HL) as an extractant. The effect of equilibrium of aqueous acidity on extraction of La3+ using Cyanex 302 in different diluents was discussed. The effects of extractant concentration and chloride ion on the extraction reaction were also studied. Stoichiometry of the extraction reactions and the nature of metal complexes formed were determined using slope analysis technique and IR measurement.

  15. Acidification of formula with citric acid is equally effective and better tolerated than acidification with hydrochloric acid.

    Science.gov (United States)

    Mehall, John R; Saltzman, Daniel A; Jackson, Richard J; Smith, Samuel D

    2002-08-01

    To determine whether acidification of formula with citric acid is equally protective against bacterial translocation and gut colonization but better tolerated than acidification with hydrochloric acid in neonatal rabbits. Paired animal model with control. Animal laboratory. Premature neonatal New Zealand rabbit pups. A standard neonatal rabbit model in two versions, a bacterial challenge and a no bacterial challenge model, was used to assess bacterial translocation and gut colonization. Two hundred forty-six rabbit pups were delivered by cesarean section 1 day premature and randomly placed into two groups sorted by type of formula acidification (hydrochloric acid or citric acid). Pups were gavage fed pH 3 kitten formula every 12 hrs. Ranitidine hydrochloride at 20 mg x kg(-1) x day(-1) was added to all formula. Bacterial challenge animals were given 1 x 10(6) colony-forming units/mL of Enterobacter cloacae with the third feeding. Animals in the no bacterial challenge group received no bacterial challenge. Animals were killed on day of life 3, and the liver, spleen, mesenteric lymph nodes, and cecum were sequentially harvested and cultured. Organs were qualitatively judged for growth, whereas cecal cultures were quantified as colony-forming units/gram. Stomach biopsies were performed to look for mucosal damage. Long-term tolerance was assessed in 48 pups fed formula acidified to pH 3 with either hydrochloric acid or citric acid and 20 animals fed pH 7 formula without ranitidine. Weight gain and mortality rate were followed for 14 days. Gut colonization and bacterial translocation to liver, spleen, and mesenteric lymph nodes were equivalent between citric acid and hydrochloric acid in both bacterial challenge and no bacterial challenge models. Long term, citric acid animals exceeded hydrochloric acid animals in daily weight gain and survival (p formula with citric acid is equally protective against bacteria but better tolerated than acidification with hydrochloric

  16. Influence of Formazan Derivatives on Corrosion Inhibition of Mild Steel in Hydrochloric Acid Medium

    OpenAIRE

    Venkatesan, P.; Anand, B.; P. Matheswaran

    2009-01-01

    Formazan of benzaldehyde (FB) and formazan of p-dimethyl amino benzaldehyde (FD) were synthesized. These compounds were studied as corrosion inhibitor for mild steel in 1.11 N hydrochloric acid by weight loss method. The result showed that the corrosion inhibition efficiency of these compounds was found to vary with the temperature and acid concentration. Also, it was found that the corrosion inhibition behaviour of FD is greater than that of FB. The kinetic treatment of the results gave firs...

  17. Inhibitory effect of some carbazides on corrosion of aluminium in hydrochloric acid and sodium hydroxide solutions

    Energy Technology Data Exchange (ETDEWEB)

    Fouda, A.S. [El-Mansoura Univ. (Egypt). Dept. of Chemistry; Madkour, L.H. [Tanta Univ. (Egypt). Dept. of Chemistry; Elshafei, A.A. [El-Mansoura Univ. (Egypt). Dept. of Chemistry; Elasklany, A.H. [El-Mansoura Univ. (Egypt). Dept. of Chemistry

    1995-06-01

    The dissolution of aluminium in hydrochloric acid and sodium hydroxide solutions in the presence of semicarbazide, thiosemicarbazide and sym.diphenylcarbazide as corrosion inhibitors has been studied using thermometric, weight-loss and polarization methods. The three methods gave consistent results. The higher inhibition efficiency of these compounds in acidic than in alkaline madia may be due to the less negative potential of aluminium in hydrochloric acid solution, favouring adsorption of the additive. The adsorption of these compounds were found to obey Frumkin adsorption isotherm. Cathodic polarization measurements showed that these compounds are cathodic inhibitors and their adsorption in the double layer does not change the mechanism of the hydrogen evolution reaction. The results are analysed in terms of both molecular and cationic adsorption. (orig.)

  18. Rare earth elements recycling from waste phosphor by dual hydrochloric acid dissolution.

    Science.gov (United States)

    Liu, Hu; Zhang, Shengen; Pan, Dean; Tian, Jianjun; Yang, Min; Wu, Maolin; Volinsky, Alex A

    2014-05-15

    This paper is a comparative study of recycling rare earth elements from waste phosphor, which focuses on the leaching rate and the technical principle. The traditional and dual dissolution by hydrochloric acid (DHA) methods were compared. The method of dual dissolution by hydrochloric acid has been developed. The Red rare earth phosphor (Y0.95Eu0.05)2O3 in waste phosphor is dissolved during the first step of acid leaching, while the Green phosphor (Ce0.67Tb0.33MgAl11O19) and the Blue phosphor (Ba0.9Eu0.1MgAl10O17) mixed with caustic soda are obtained by alkali sintering. The excess caustic soda and NaAlO2 are removed by washing. The insoluble matter is leached by the hydrochloric acid, followed by solvent extraction and precipitation (the DHA method). In comparison, the total leaching rate of the rare earth elements was 94.6% by DHA, which is much higher than 42.08% achieved by the traditional method. The leaching rate of Y, Eu, Ce and Tb reached 94.6%, 99.05%, 71.45%, and 76.22%, respectively. DHA can decrease the consumption of chemicals and energy. The suggested DHA method is feasible for industrial applications.

  19. Experimental and quantum chemical studies on corrosion inhibition performance of fluconazole in hydrochloric acid solution

    Indian Academy of Sciences (India)

    P Malekmohammadi Nouri; M M Attar

    2015-04-01

    The corrosion inhibition effect of fluconazole (FLU) was investigated on steel in 1 M hydrochloric acid solution. Weight loss measurements and atomic force microscope analysis were utilized to investigate the corrosion inhibition properties and film formation behaviour of FLU. Quantum chemical approach was also used to calculate some electronic properties of the molecule in neutral and protonated form in order to find any correlation between the inhibition effect and molecular structure of FLU molecule. The results showed that FLU can act as a good corrosion inhibitor for steel in hydrochloric acid solution at different temperatures and it can inhibit steel corrosion up to 95%. The adsorption followed the Langmuir isotherm and the thermodynamic parameters were also determined and discussed. Quantum chemical studies showed that in adsorption process of FLU molecules, nitrogen and oxygen atoms and benzene ring act as active centres.

  20. Pretreatment of corn stover for sugar production using dilute hydrochloric acid followed by lime.

    Science.gov (United States)

    Zu, Shuai; Li, Wen-zhi; Zhang, Mingjian; Li, Zihong; Wang, Ziyu; Jameel, Hasan; Chang, Hou-min

    2014-01-01

    In this study, a two stage process was evaluated to increase the sugar recovery. Firstly, corn stover was treated with diluted hydrochloric acid to maximize the xylose yield, and then the residue was treated with lime to alter the lignin structure and swell the cellulose surface. The optimal condition was 120 °C and 40 min for diluted hydrochloric acid pretreatment followed by lime pretreatment at 60 °C for 12h with lime loading at 0.1 g/g of substrate. The glucose and xylose yield was 78.0% and 97.0%, respectively, with cellulase dosage at 5 FPU/g of substrate. The total glucose yield increased to 85.9% when the cellulase loading was increased to 10 FPU/g of substrate. This two stage process was effective due to the swelling of the internal surface, an increase in the porosity and a decrease in the degree of polymerization.

  1. A Concentrated Hydrochloric Acid-based Method for Complete Recovery of DNA from Bone.

    Science.gov (United States)

    Huynen, Leon; Lambert, David M

    2015-11-01

    The successful extraction of DNA from historical or ancient animal bone is important for the analysis of discriminating genetic markers. Methods used currently rely on the digestion of bone with EDTA and proteinase K, followed by purification with phenol/chloroform and silica bed binding. We have developed a simple concentrated hydrochloric acid-based method that precludes the use of phenol/chloroform purification and can lead to a several-fold increase in DNA yield when compared to other commonly used methods. Concentrated hydrochloric acid was shown to dissolve most of the undigested bone and allowed the efficient recovery of DNA fragments <100 bases in length. This method should prove useful for the recovery of DNAs from highly degraded animal bone, such as that found in historical or ancient samples.

  2. ANTICORROSION POTENTIAL OF HYDRALAZINE FOR CORROSION OF MILD STEEL IN 1M HYDROCHLORIC ACID SOLUTION

    Directory of Open Access Journals (Sweden)

    B. M. Prasanna

    2015-05-01

    Full Text Available Anticorrosion potential of mild steel by Hydralazine as corrosion inhibitor for mild steel in 1M hydrochloric acid was investigated by chemical and electrochemical measurements at 303-333 K temperature. The maximum inhibition efficiency of inhibitor by Weight loss method is around 90%, Tafel polarization method is around 85%; electrochemical impedance spectroscopy measurement around 90% at 1250 ppm of Hydralazine in. The result shows that the inhibition efficiency increases with I 1M hydrochloric acid. Hydralazine acts as a mixed type inhibitor which inhibits the corrosion of mild steel due to the adsorption on metal surface. This adsorption system obeys the Langmuir adsorption isotherm.Activation parameters explains the effect of temperature with inhibition efficiency of inhibitor molecule.SEM images of inhibited mild steel strips shows a formation of passive protective film over the surface.

  3. Acid hydrolysis of corn stover using hydrochloric acid: Kinetic modeling and statistical optimization

    Directory of Open Access Journals (Sweden)

    Sun Yong

    2014-01-01

    Full Text Available The hydrolysis of corn stover using hydrochloric acid was studied. The kinetic parameters of the mathematical models for predicting the yields of xylose, glucose, furfural and acetic acid were obtained, and the corresponding xylose generation activation energy of 100 kJ/mol was determined. The characterization of corn stover using with different techniques during hydrolysis indicated an effective removal of xylan and the slightly alteration on the structures of cellulose and lignin. A 23five levels Central Composite Design (CCD was used to develop a statistical model for the optimization of process variables including acid concentration, pretreatment temperature and time. The optimum conditions determined by this model were found to be 108ºC for 80 minutes with acid concentration of 5.8%. Under these conditions, the maximised results are the following: xylose 19.93 g/L, glucose 1.2 g/L, furfural 1.5 g/L, acetic acid 1.3 g/L. The validation of the model indicates a good agreement between the experimental results and the predicted values.

  4. Inhibition of Mild Steel Corrosion in Hydrochloric Acid Solution by Ciprofloxacin Drug

    OpenAIRE

    2013-01-01

    The inhibition of mild steel corrosion in hydrochloric acid solution by ciprofloxacin drug as an eco-friendly and commercially available inhibitor was studied at room temperature by weight loss technique. It was found that the test drug has a promising inhibitory action against corrosion of mild steel in the medium investigated. The inhibition efficiency was found to increase with a corresponding increase in the concentration of the inhibitor. It was also found that the adsorption as well as ...

  5. Corrosion Inhibition Synergism between Lanthanum(Ⅲ) Ion and 8-Hydroxyquinoline for Zinc in Hydrochloric Acid

    Institute of Scientific and Technical Information of China (English)

    木冠南; 唐丽斌; 李学铭

    2002-01-01

    The effects of La3+ ion and chelate reagent 8-hydroxyquinoline on the corrosion rate of zinc in hydrochloric acid were investigated by using weight loss method and electrochemical method. It is found that in a specific concentration range of La3+ ion and 8-hydroxyquinoline, the obvious corrosion inhibition synergism is obtained. The mechanism of corrosion inhibition synergism was discussed on basis of adsorption theory.

  6. Kinetics of Sawdust Hydrolysis with Dilute Hydrochloric Acid and Ferrous Chloride

    Institute of Scientific and Technical Information of China (English)

    袁传敏; 颜涌捷; 任铮伟; 李庭琛; 曹建勤

    2004-01-01

    With dilute hydrochloric acid as catalyst and promoted by ferrous chloride, hydrolysis of waste sawdust to produce monosaccharides was conducted by using an one-step method in a batch-wise operation reactor. Based on the model of first order consecutive irreversible reactions, the kinetics equation incorporating the term of catalyst concentration was obtained that is suitable for describing the hydrolysis of sawdust. Activation energies were calculated for hydrolysis of sawdust and decomposition of monosaccharides.

  7. Effect of dentifrices against hydrochloric acid-induced erosion.

    Science.gov (United States)

    Messias, Danielle Cristine; Maeda, Fernando Akio; Turssi, Cecilia Pedroso; Serra, Mônica Campos

    2011-01-01

    This in vitro investigation assessed whether different dentifrices would be capable of controlling the enamel erosion progression caused by HCl. Sixty bovine enamel slabs were covered with acid-resistant varnish, except for a 2.5-mm2 circular area on the labial surface. According to a complete block design, the experimental units were immersed in HCl solution (pH 1.2; 0.1M). After storage in artificial saliva for 1 h, specimens (n = 15) were exposed to different dentifrices: Sensodyne Cool Gel (1100 ppm F), Sensodyne ProNamel (1450 ppm F), and PrevDent 5000 (5000 ppm F). The control group was immersed in deionised water. Following five cycles of erosive challenge, the slabs were prepared for porosity evaluation using solutions of copper sulfate and rubeanic acid. ANOVA demonstrated no difference in the enamel porosity as a function of the dentifrice employed (P = 0.5494). The damage caused by a simulated intrinsic erosive challenge seems unable to be controlled by fluoridated dentifrices, even when this ion is found in elevated concentrations.

  8. Corrosion inhibition of iron in hydrochloric acid by polyacrylamide

    Directory of Open Access Journals (Sweden)

    DRAGICA CHAMOVSKA

    2007-07-01

    Full Text Available The corrosion protection and/or adsorption of polyacrylamide (PAA of number average molecular weight, , between 15,000 – 1,350,000 g mol-1 on mild steel and iron (99.99 % Fe in 3 M HCl at room temperature was studied using spectrophotometry (the phenanthroline method, the weight loss method and EIS (Electrochemical Impedance Spectroscopy. It was found that the corrosion protect­tion efficiency of the PAA – adsorbed layers strongly depends on both the molar concentration of PAA in the solution and its molecular weight, reaching limiting values between 85 and 96 %. Simultaneously, it was also concluded that a relatively high surface coverage could be obtained with very low PAA concentrations (0.5 – 2 ppm, indicating the good adsorption characteristics of PAA on mild steel and iron in hydrochloride acid. The experimentally obtained results follow a Lan­gmuir adsorption isotherm. According to the best fitting parameters, the adsorption coef­f­i­cient B ranged between 2×107 and 4×108 mol-1 and depended strongly on the mole­cular weight of the PAA: B = k (for a ≈ 0.67 and k = 2.95×104 or the size of the polymer coil. As was found by EIS, the thickness of the adsorbed PAA layer was approx. 1.1 nm (for er = 15 and corresponded only to the polymer segments attached to the metal surface. On the other hand, as was found by ellipsometry, the limiting layer of the adsorbed PAA molecules was highly voluminous and relatively thick (100 – 200 nm, containing entangled polymer coils.

  9. Investigating the Acid Failure of Aluminium Alloy in 2 M Hydrochloric Acid Using Vernonia amygdalina

    Directory of Open Access Journals (Sweden)

    Olugbenga A. Omotosho

    2012-04-01

    Full Text Available The acid failure of aluminium alloy in 2 M hydrochloric acid solution in the presence of Vernonia amygdalina extract was investigated using gasometric technique. Aluminium alloy coupons of dimension 4 cm by 1 cm were immersed in test solutions of free acid and also those containing extract volumes of 2, 3, 4 and 5 cm3 at ambient temperature for 30 minutes. The volumes of hydrogen gas evolved as a result of the rate of reaction were recorded and analyzed. Analysis revealed that maximum inhibitor efficiency which corresponds to the lowest corrosion rate was obtained at optimum inhibitor volumes of 5 cm3, with reduction in the corrosion rate observed to follow in order of increasing extract volumes. Adsorption study revealed that Temkin isotherm best described the metal surface interaction with the extract phytochemicals, with 12 minutes becoming the best exposure time for the phytochemicals to adsorb to the metal surface at all volumes. Statistical modelling of the corrosion rate yielded an important relationship suitable for estimating corrosion rate values once volumes of the extract is known. Microstructural studies, showed an indirect relationship between crack growth rates and extract volumes, while consistency of the irregular intermetallic phases increases with increasing extract volumes.

  10. Thermodynamics and kinetics of lutetium extraction with HEH(EHP) in hydrochloric acid medium

    Institute of Scientific and Technical Information of China (English)

    DONG Jinshi; XU Yang; WANG Liangshi; HUANG Xiaowei; LONG Zhiqi; WU Shengxi

    2016-01-01

    Solvent extraction has been the most widely used technique for rare earths separation. In this study, thermodynamics and kinetics of lutetium extraction with HEH (EHP) in hydrochloric acid medium were investigated. The extraction mechanism and the relevant parameters were determined by experiment research which can guide the practical extraction process. The data indicated that chloride ion had no effect on lutetium extraction, the rate constant increased when stirring speed was enhanced. Effects of temperature, HEH (EHP) concentration, acidity, and chloride concentration were also studied. Thickness of the diffusion film was also calculated to be 4.66×10–3 cm at 150 r/min.

  11. Influence of Formazan Derivatives on Corrosion Inhibition of Mild Steel in Hydrochloric Acid Medium

    Directory of Open Access Journals (Sweden)

    P. Venkatesan

    2009-01-01

    Full Text Available Formazan of benzaldehyde (FB and formazan of p-dimethyl amino benzaldehyde (FD were synthesized. These compounds were studied as corrosion inhibitor for mild steel in 1.11 N hydrochloric acid by weight loss method. The result showed that the corrosion inhibition efficiency of these compounds was found to vary with the temperature and acid concentration. Also, it was found that the corrosion inhibition behaviour of FD is greater than that of FB. The kinetic treatment of the results gave first order kinetics. The relative corrosion inhibition efficiency of these compounds has been explained on the basis of structure dependent - electron donor properties of the inhibitors.

  12. Formation of linear polyenes in poly(vinyl alcohol) films catalyzed by phosphotungstic acid, aluminum chloride, and hydrochloric acid

    Science.gov (United States)

    Tretinnikov, O. N.; Sushko, N. I.; Malyi, A. B.

    2016-07-01

    Formation of linear polyenes-(CH=CH)n-via acid-catalyzed thermal dehydration of polyvinyl alcohol in 9- to 40-µm-thick films of this polymer containing hydrochloric acid, aluminum chloride, and phosphotungstic acid as dehydration catalysts was studied by electronic absorption spectroscopy. The concentration of long-chain ( n ≥ 8) polyenes in films containing phosphotungstic acid is found to monotonically increase with the duration of thermal treatment of films, although the kinetics of this process is independent of film thickness. In films containing hydrochloric acid and aluminum chloride, the formation rate of polyenes with n ≥ 8 rapidly drops as film thickness decreases and the annealing time increases. As a result, at a film thickness of less than 10-12 µm, long-chain polyenes are not formed at all in these films no matter how long thermal duration is. The reason for this behavior is that hydrochloric acid catalyzing polymer dehydration in these films evaporates from the films during thermal treatment, the evaporation rate inversely depending on film thickness.

  13. Effect of beverages on bovine dental enamel subjected to erosive challenge with hydrochloric acid.

    Science.gov (United States)

    Amoras, Dinah Ribeiro; Corona, Silmara Aparecida Milori; Rodrigues, Antonio Luiz; Serra, Mônica Campos

    2012-01-01

    This study evaluated by an in vitro model the effect of beverages on dental enamel previously subjected to erosive challenge with hydrochloric acid. The factor under study was the type of beverage, in five levels: Sprite® Zero Low-calorie Soda Lime (positive control), Parmalat® ultra high temperature (UHT) milk, Ades® Original soymilk, Leão® Ice Tea Zero ready-to-drink low-calorie peach-flavored black teaand Prata® natural mineral water (negative control). Seventy-five bovine enamel specimens were distributed among the five types of beverages (n=15), according to a randomized complete block design. For the formation of erosive wear lesions, the specimens were immersed in 10 mL aqueous solution of hydrochloric acid 0.01 M for 2 min. Subsequently, the specimens were immersed in 20 mL of the beverages for 1 min, twice daily for 2 days at room temperature. In between, the specimens were kept in 20 mL of artificial saliva at 37ºC. The response variable was the quantitative enamel microhardness. ANOVA and Tukey's test showed highly significant differences (penamel exposed to hydrochloric acid and beverages. The soft drink caused a significantly higher decrease in microhardness compared with the other beverages. The black tea caused a significantly higher reduction in microhardness than the mineral water, UHT milk and soymilk, but lower than the soft drink. Among the analyzed beverages, the soft drink and the black tea caused the most deleterious effects on dental enamel microhardness.

  14. Determination of uranium isotopes in environmental samples by anion exchange in sulfuric and hydrochloric acid media.

    Science.gov (United States)

    Popov, L

    2016-09-01

    Method for determination of uranium isotopes in various environmental samples is presented. The major advantages of the method are the low cost of the analysis, high radiochemical yields and good decontamination factors from the matrix elements, natural and man-made radionuclides. The separation and purification of uranium is attained by adsorption with strong base anion exchange resin in sulfuric and hydrochloric acid media. Uranium is electrodeposited on a stainless steel disk and measured by alpha spectrometry. The analytical method has been applied for the determination of concentrations of uranium isotopes in mineral, spring and tap waters from Bulgaria. The analytical quality was checked by analyzing reference materials.

  15. Inhibition of Mild Steel Corrosion in Hydrochloric Acid Solution by Ciprofloxacin Drug

    Directory of Open Access Journals (Sweden)

    Inemesit A. Akpan

    2013-01-01

    Full Text Available The inhibition of mild steel corrosion in hydrochloric acid solution by ciprofloxacin drug as an eco-friendly and commercially available inhibitor was studied at room temperature by weight loss technique. It was found that the test drug has a promising inhibitory action against corrosion of mild steel in the medium investigated. The inhibition efficiency was found to increase with a corresponding increase in the concentration of the inhibitor. It was also found that the adsorption as well as the inhibition process followed a first-order kinetics and obeyed Langmuir’s adsorption isotherm.

  16. Effect of molecular structure of aniline-formaldehyde copolymers on corrosion inhibition of mild steel in hydrochloric acid solution.

    Science.gov (United States)

    Zhang, Yan; Nie, Mengyan; Wang, Xiutong; Zhu, Yukun; Shi, Fuhua; Yu, Jianqiang; Hou, Baorong

    2015-05-30

    Aniline-formaldehyde copolymers with different molecular structures have been prepared and investigated for the purpose of corrosion control of mild steel in hydrochloric acid. The copolymers were synthesized by a condensation polymerization process with different ratios of aniline to formaldehyde in acidic precursor solutions. The corrosion inhibition efficiency of as-synthesized copolymers for Q235 mild steel was investigated in 1.0 mol L(-1) hydrochloric acid solution by weight loss measurement, potentiodynamic polarization, and electrochemical impedance spectroscopy, respectively. All the results demonstrate that as-prepared aniline-formaldehyde copolymers are efficient mixed-type corrosion inhibitors for mild steels in hydrochloric acid. The corrosion inhibition mechanism is discussed in terms of the role of molecular structure on adsorption of the copolymers onto the steel surface in acid solution.

  17. Recovery of Co(Ⅱ) and Ni(Ⅱ) from hydrochloric acid solution of alloy scrap

    Institute of Scientific and Technical Information of China (English)

    SHEN Yong-feng; XUE Wen-ying; NIU Wen-yong

    2008-01-01

    A hydrometallurgical process was developed for recovery of nickel and cobalt from the hydrochloric acid leaching solution of alloy scraps. The process consists of five major unit operations: 1) leaching with 6 mol/L hydrochloric acid under the L/S ratio of 10:1 at 95 ℃ for 3 h; 2) copper replacement by iron scraps under pH value of 2.0 at 80 ℃, and stirring for 1 h; 3) removal of iron and chromium by chemical precipitation: iron removal under pH value of 2.0 at 90 ℃ by dropwise addition of sodium chlorate and 18% sodium carbonate solution, then chromium removal under pH value of 4.0 at 70 ℃ by addition of nickel carbonate solution, stirred by air flow for 2 h; 4) selective separation of cobalt from nickel by extraction using 30% trialkyl amine+50% kerosene (volume fraction) and tri-n-butylphosphate (TBP) as a phase modifier with the O/A ratio of 2:1, and stripping of cobalt with 0.01 mol/L HC1; 5) crystallization of nickel chloride and electrodeposition of cobalt. It is found that the nickel recovery of 95% and the cobalt recovery of approximately 60% with purity over 99.9% are obtained by this process.

  18. Kinetic Aspects of Leaching Zinc from Waste Galvanizing Zinc by Using Hydrochloric Acid Solutions

    Science.gov (United States)

    Sminčáková, Emília; Trpčevská, Jarmila; Pirošková, Jana

    2017-10-01

    In this work, the results of acid leaching of flux skimmings coming from two plants are presented. Sample A contained two phases, Zn(OH)Cl and NH4Cl. In sample B, the presence of three phases, Zn5(OH)8Cl2·H2O, (NH4)2(ZnCl4) and ZnCl2(NH3)2, was proved. The aqueous solution of hydrochloric acid and distilled water was used as the leaching medium. The effects of the leaching time, temperature and concentration of the leaching medium on the zinc extraction were investigated. The apparent activation energy, E a = 4.61 kJ mol-1, and apparent reaction order n = 0.18 for sample A, and the values E a = 6.28 kJ mol-1 and n = 0.33 for sample B were experimentally determined. Zinc leaching in acid medium is a diffusion-controlled process.

  19. Kinetic Aspects of Leaching Zinc from Waste Galvanizing Zinc by Using Hydrochloric Acid Solutions

    Science.gov (United States)

    Sminčáková, Emília; Trpčevská, Jarmila; Pirošková, Jana

    2016-10-01

    In this work, the results of acid leaching of flux skimmings coming from two plants are presented. Sample A contained two phases, Zn(OH)Cl and NH4Cl. In sample B, the presence of three phases, Zn5(OH)8Cl2·H2O, (NH4)2(ZnCl4) and ZnCl2(NH3)2, was proved. The aqueous solution of hydrochloric acid and distilled water was used as the leaching medium. The effects of the leaching time, temperature and concentration of the leaching medium on the zinc extraction were investigated. The apparent activation energy, E a = 4.61 kJ mol-1, and apparent reaction order n = 0.18 for sample A, and the values E a = 6.28 kJ mol-1 and n = 0.33 for sample B were experimentally determined. Zinc leaching in acid medium is a diffusion-controlled process.

  20. Direct Spectroscopic Determination of Europium(Ⅱ) Concentration During Europium(Ⅲ) Electro-Reduction in Hydrochloric Acid Medium

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    UV-Vis spectroscopy was used to directly determine the concentration of Eu(Ⅱ) during electroreduction of Eu(Ⅲ) in hydrochloric acid medium. Electroreduction was carried out in a flow type electrolyzer with glassy carbon cathode at the constant potential of -800 mV vs. Ag/AgCl. The effects of oxygen and concentration of hydrochloric acid on the system were investigated. For 0.01 mol·L-1 hydrochloric acid, calibration curves for Eu(Ⅱ) absorption bands at 248 and 320 nm were constructed. Molar absorption coefficients were estimated to be 2016 and 648 L·mol-1·cm-1, respectively. The absorbance strongly decreased with decrease in pH of the solution, whereas concentration of chloride had only a negligible effect.

  1. The Comparison of Hydrochloric Acid and Phosphoric Acid Treatments in the Preparation of Montmorillonite Catalysts for RNA Synthesis

    Science.gov (United States)

    Aldersley, Michael Frank; Joshi, Prakash C.; Huang, Yixing

    2017-02-01

    The treatment of clay minerals with a preliminary acid wash and titration to pH 7 has proven to generate catalysts for the most interesting of oligomerization reactions in which activated RNA-nucleotides generate oligomers up to 40-mers. Significantly, not all clay minerals become catalytic following this treatment and none are catalytic in the absence of such treatment. The washing procedure has been modified and explored further using phosphoric acid and the outcomes are compared to those obtained when clay samples are prepared following a hydrochloric acid wash.

  2. Integrated Computational and Experimental Protocol for Understanding Rh(III) Speciation in Hydrochloric and Nitric Acid Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Samuels, Alex C.; Boele, Cherilynn A.; Bennett, Kevin T.; Clark, Sue B.; Wall, Nathalie; Clark, Aurora E.

    2014-12-01

    A combined experimental and theoretical approach has investigated the complex speciation of Rh(III) in hydrochloric and nitric acid media, as a function of acid concentration. This has relevance to the separation and isolation of Rh(III) from dissolved spent nuclear fuel, which is an emergent and attractive alternative source of platinum group metals, relative to traditional mining efforts.

  3. EDTA and hydrochloric acid effects on mercury accumulation by Lupinus albus.

    Science.gov (United States)

    Rodríguez, Luis; Alonso-Azcárate, Jacinto; Villaseñor, José; Rodríguez-Castellanos, Laura

    2016-12-01

    The efficiency of white lupine (Lupinus albus) to uptake and accumulate mercury from a soil polluted by mining activities was assessed in a pot experiment with chemically assisted phytoextraction. The mobilizing agents tested were ethylenediaminetetracetic acid (EDTA) and hydrochloric acid (HCl). Two doses of each amendment were used (0.5 and 1.0 g of amendment per kg of soil), and unamended pots were used as a control. Addition of HCl to the soil did not negatively affect plant biomass, while the use of EDTA led to a significant decrease in plant growth when compared to that found for non-treated pots, with plants visually showing symptoms of toxicity. The addition of hydrochloric acid increased root, shoot and total plant Hg uptake of white lupine by 3.7 times, 3.1 times and 3.5 times, respectively, in relation to non-amended plants. The greatest efficiency was obtained for the highest HCl dose. EDTA led to higher concentrations of total plant Hg than that found with the control, but, due to the aforementioned decrease in plant biomass, the Hg phytoextraction yield was not significantly increased. These results were attributed to the capability of both amendments to form stable Hg complexes. The concentration of Hg in the water of the soil pores after the phytoextraction experiment was very low for all treatments, showing that risks derived from metal leaching could be partially avoided by using doses and chemicals suitable to the concentration of metal in the soil and plant performance.

  4. Anomalous spin polarization in the photoreduction of chromone-2-carboxylic acid with alcohol induced by hydrochloric acid

    Science.gov (United States)

    Ohara, Keishi; Mukai, Kazuo

    2000-02-01

    The addition effect of hydrochloric acid (HCl) on the photoreduction of chromone-2-carboxylic acid (CRCA) is studied by time-resolved EPR. The EPR lines of CRCA ketyl radical show an enhanced absorption in the presence of HCl, while without HCl these show an emissive character. On the other hand, the lines of the CRCA alkyl type radical show an emissive character whether HCl is included or not. The simultaneous reactions of the closely-lying two excited triplet states (T 1 and T 2) of CRCA may induce the above anomalous CIDEP behavior.

  5. Comparison of sulfuric and hydrochloric acids as catalysts in hydrolysis of Kappaphycus alvarezii (cottonii).

    Science.gov (United States)

    Meinita, Maria Dyah Nur; Hong, Yong-Ki; Jeong, Gwi-Taek

    2012-01-01

    In this study, hydrolysis of marine algal biomass Kappaphhycus alvarezii using two different acid catalysts was examined with the goal of identifying optimal reaction conditions for the formation of sugars and by-products. K. alvarezii were hydrolyzed by autoclave using sulfuric acid or hydrochloric acid as catalyst with different acid concentrations (0.1-1.0 M), substrate concentrations (1.0-13.5%), hydrolysis time (10-90 min) and hydrolysis temperatures (100-130 (°)C). A difference in galactose, glucose, reducing sugar and total sugar content was observed under the different hydrolysis conditions. Different by-product compounds such as 5-hydroxymethylfurfural and levulinic acid were also observed under the different reaction conditions. The optimal conditions for hydrolysis were achieved at a sulfuric acid concentration, temperature and reaction time of 0.2 M, 130 °C and 15 min, respectively. These results may provide useful information for the development of more efficient systems for biofuel production from marine biomass.

  6. Detection of anhydrous hydrochloric acid, HCl, in IRC+10216 with the Herschel SPIRE and PACS spectrometers

    CERN Document Server

    Cernicharo, J; Barlow, M J; Agundez, M; Royer, P; Vandenbussche, B; Wesson, R; Polehampton, E T; De Beck, E; Blommaert, J A D L; Daniel, F; De Meester, W; Exter, K M; Feuchtgruber, H; Gear, W K; Goicoechea, J R; Gomez, H L; Groenewegen, M A T; Hargrave, P C; Huygen, R; Imhof, P; Ivison, R J; Jean, C; Kerschbaum, F; Leeks, S J; Lim, T L; Matsuura, M; Olofsson, G; Posch, T; Regibo, S; Savini, G; Sibthorpe, B; Swinyard, B M; Vandenbussche, B; Waelkens, C

    2010-01-01

    We report on the detection of anhydrous hydrochloric acid (hydrogen chlorine, HCl) in the carbon-rich star IRC+10216 using the spectroscopic facilities onboard the Herschel satellite. Lines from J=1-0 up to J=7-6 have been detected. From the observed intensities, we conclude that HCl is produced in the innermost layers of the circumstellar envelope with an abundance relative to H2 of 5x10^-8 and extends until the molecules reach its photodissociation zone. Upper limits to the column densities of AlH, MgH, CaH, CuH, KH, NaH, FeH, and other diatomic hydrides have also been obtained.

  7. Hydrochloric acid recovery from rare earth chloride solutions by vacuum membrane distillation

    Institute of Scientific and Technical Information of China (English)

    TANG Jianjun; ZHOU Kanggen

    2006-01-01

    The possibility of the recovery of hydrochloric acid from rare earth (RE) chloride solutions was first experimentally studied by batch vacuum membrane distillation (VMD). The recovery by continuous VMD was also studied to devise methods that enabled the operation of VMD setup in a stable condition as well as to increase the membrane-operating life The results indicated that HCl separation with RE by VMD was possible, and the recovery ratio of 80% could be achieved by batch VMD. In continuous VMD, when the temperature of circular solutions, circular rate, and downstream pressure was62-63℃, 5.4 cm/s, and 9.33 kPa, respectively, the HCl concentration in circular solutions and the processing capacity per membrane area were obtained. The mathematical results were in accordance with the experimental ones.

  8. Molecular Structure of Phenylthiourea as a Corrosion Inhibitor for Mild Steel in Hydrochloric Acid

    Institute of Scientific and Technical Information of China (English)

    Anees A, Khadom

    2011-01-01

    The application of statistical analysis and quantum chemical models on the corrosion inhibition of mild steel in hydrochloric acid in presence of phenylthiourea (PTU) as corrosion inhibitor have been investigated. Two mathematical models were used, second order polynomial model and Arrhenius type equation model. STATISTICA software based on Levenberg-Marquardt estimation method was used to evaluate the coefficients of two Models. It follows that the two models were suitable to represent the corrosion rate data at different conditions. The correlation coefficient of second order polynomial model was 0.973, while for the Arrhenius type model was 0.919. The structure of inhibitor was optimized by ArgusLab 4.0.1 package. The quantum chemical parameters (EHoMO, ELUMO, AE, and dipole moment μ) were estimated by PM3-SCF method.

  9. Use of hydrochloric acid for determinining solid-phase arsenic partitioning in sulfidic sediments.

    Science.gov (United States)

    Wilkin, Richard T; Ford, Robert G

    2002-11-15

    We examined the use of room-temperature hydrochloric acid (1-6 M) and salt solutions of magnesium chloride, sodium carbonate, and sodium sulfide for the removal of arsenic from synthetic iron monosulfides and contaminated sediments containing acid-volatile sulfides (AVS). Results indicate that acid-soluble arsenic reacts with H2S released from AVS phases and precipitates at low pH as disordered orpiment or alacranite. Arsenic sulfide precipitation is consistent with geochemical modeling in that conditions during acid extraction are predicted to be oversaturated with respect to orpiment, realgar, or both. Binding of arsenic with sulfide at low pH is sufficiently strong that 6 M HCl will not keep spiked arsenic in the dissolved fraction. Over a wide range of AVS concentrations and molar [As]/[AVS] ratios, acid extraction of arsenic from sulfide-bearing sediments will give biased results that overestimate the stability or underestimate the bioavailability of sediment-bound arsenic. Alkaline solutions of sodium sulfide and sodium carbonate are efficient in removing arsenic from arsenic sulfides and mixed iron-arsenic sulfides because of the high solubility of arsenic at alkaline pH, the formation of stable arsenic complexes with sulfide or carbonate, or both.

  10. Cellulose acetate layer effect toward aluminium corrosion rate in hydrochloric acid media

    Science.gov (United States)

    Andarany, K. S.; Sagir, A.; Ahmad, A.; Deni, S. K.; Gunawan, W.

    2017-09-01

    Corrosion occurs due to the oxidation and reduction reactions between the material and its environment. The oxidation reaction defined as reactions that produce electrons and reduction is between two elements that bind the electrons. Corrosion cannot be inevitable in life both within the industry and household. Corrosion cannot eliminate but can be control. According to the voltaic table, Aluminum is a metal that easily corroded. This study attempts to characterize the type of corrosion by using a strong acid media (HCl). Experiment using a strong acid (HCl), at a low concentration that occurs is pitting corrosion, whereas at high concentrations that occurs is corrosion erosion. One of prevention method is by using a coating method. An efforts are made to slow the rate of corrosion is by coating the metal with “cellulose acetate” (CA). cellulose acetate consisted of cellulose powder dissolved in 99% acetic acid, and then applied to the aluminum metal. Soaking experiments using hydrochloric acid, cellulose acetate is able to slow down the corrosion rate of 47 479%.

  11. Extraction of gold from hydrochloric acid solutions by Alamine 336 and Alkylaniline

    Directory of Open Access Journals (Sweden)

    Natalya Dolgova

    2013-09-01

    Full Text Available The extraction of gold with 336 Alamin and Alkylaniline from hydrochloric acid solutions was studied. Shown that Alamin extracts gold quantitatively in the field of acidity of the aqueuous phase pH=3,0 – СHCl=3,5 M when used as diluents of kerosene and higher carboxylic acids in admixture with paraffin. The time of quantitative extraction of gold: with Alamin – 3 minutes, with Alkylaniline – 5 minutes, regardless of the choice of diluent. The composition of the extracted complex and scheme of  gold extraction process with Alamin was proposed. Extraction of gold with 5%- Alamin-HCA-paraffin can be used for development of a combined extraction -  X-ray fluorescence technique for determination of gold because the resulting solids extracts meet the requirements imposed on emitters samples in X-ray fluorescence analysis. Calibration characteritstic is linear in the range of gold content in the samples emitters 0,006-0,17 wt%.

  12. Enhanced Blood Compatibility of Metallocene Polyethylene Subjected to Hydrochloric Acid Treatment for Cardiovascular Implants

    Directory of Open Access Journals (Sweden)

    Saravana Kumar Jaganathan

    2014-01-01

    Full Text Available Blood compatibility of metallocene polyethylene (mPE was investigated after modifying the surface using hydrochloric acid. Contact angle of the mPE exposed to HCl poses a decrease in its value which indicates increasing wettability and better blood compatibility. Surface of mPE analyzed by using FTIR revealed no significant changes in its functional groups after treatment. Furthermore, scanning electron microscope images supported the increasing wettability through the modifications like pit formations and etching on the acid rendered surface. To evaluate the effect of acid treatment on the coagulation cascade, prothrombin time (PT and activated partial thromboplastin time (APTT were measured. Both PT and APTT were delayed significantly (P<0.05 after 60 min exposure implying improved blood compatibility of the surfaces. Hemolysis assay of the treated surface showed a remarkable decrease in the percentage of lysis of red blood cells when compared with untreated surface. Moreover, platelet adhesion assay demonstrated that HCl exposed surfaces deter the attachment of platelets and thereby reduce the chances of activation of blood coagulation cascade. These results confirmed the enhanced blood compatibility of mPE after HCl exposure which can be utilized for cardiovascular implants like artificial vascular prostheses, implants, and various blood contacting devices.

  13. Quantitative Leaching of a Spent Cell Phone Printed Circuit Board by Hydrochloric acid

    Directory of Open Access Journals (Sweden)

    Alafara A. Baba

    2014-07-01

    Full Text Available This paper presents a kinetic data on the hydrometallurgical recovery of some metal ions from a printed circuit board (PCB of a spent cell phone by hydrochloric acid leaching. The effects of acid concentration, temperature and particle diameter on the dissolution efficiency at various leaching time intervals were examined. The results of the leaching investigations showed that the powdered cell phone dissolution increases with increasing acid concentration, system temperature with decreasing particle diameter at 360 rpm. With 2M HCl solution, about 88.49% of the sample was dissolved within 120 minutes using 0.075-0.112 mm particle diameter at 800 C. The results of the study indicated that the dissolution reaction could be represented by a shrinking core model with surface chemical reaction. A value of 0.61, 60.67 kJ/mol and 12.9s-1 were calculated as reaction order, activation energy and frequency factor, respectively for the dissolution process.

  14. Surface chemical compositions and dispersity of starch nanocrystals formed by sulfuric and hydrochloric acid hydrolysis.

    Science.gov (United States)

    Wei, Benxi; Xu, Xueming; Jin, Zhengyu; Tian, Yaoqi

    2014-01-01

    Surface chemical compositions of starch nanocrystals (SNC) prepared using sulfuric acid (H2SO4) and hydrochloric acid (HCl) hydrolysis were analyzed by X-ray photoelectron spectroscopy (XPS) and FT-IR. The results showed that carboxyl groups and sulfate esters were presented in SNC after hydrolysis with H2SO4, while no sulfate esters were detected in SNC during HCl-hydrolysis. TEM results showed that, compared to H2SO4-hydrolyzed sample, a wider size distribution of SNC prepared by HCl-hydrolysis were observed. Zeta-potentials were -23.1 and -5.02 mV for H2SO4- and HCl-hydrolyzed SNC suspensions at pH 6.5, respectively. Nevertheless, the zeta-potential values decreased to -32.3 and -10.2 mV as the dispersion pH was adjusted to 10.6. After placed 48 h at pH 10.6, zeta-potential increased to -24.1 mV for H2SO4-hydrolyzed SNC, while no change was detected for HCl-hydrolyzed one. The higher zeta-potential and relative small particle distribution of SNC caused more stable suspensions compared to HCl-hydrolyzed sample.

  15. Surface chemical compositions and dispersity of starch nanocrystals formed by sulfuric and hydrochloric acid hydrolysis.

    Directory of Open Access Journals (Sweden)

    Benxi Wei

    Full Text Available Surface chemical compositions of starch nanocrystals (SNC prepared using sulfuric acid (H2SO4 and hydrochloric acid (HCl hydrolysis were analyzed by X-ray photoelectron spectroscopy (XPS and FT-IR. The results showed that carboxyl groups and sulfate esters were presented in SNC after hydrolysis with H2SO4, while no sulfate esters were detected in SNC during HCl-hydrolysis. TEM results showed that, compared to H2SO4-hydrolyzed sample, a wider size distribution of SNC prepared by HCl-hydrolysis were observed. Zeta-potentials were -23.1 and -5.02 mV for H2SO4- and HCl-hydrolyzed SNC suspensions at pH 6.5, respectively. Nevertheless, the zeta-potential values decreased to -32.3 and -10.2 mV as the dispersion pH was adjusted to 10.6. After placed 48 h at pH 10.6, zeta-potential increased to -24.1 mV for H2SO4-hydrolyzed SNC, while no change was detected for HCl-hydrolyzed one. The higher zeta-potential and relative small particle distribution of SNC caused more stable suspensions compared to HCl-hydrolyzed sample.

  16. Impact of α-amylase combined with hydrochloric acid hydrolysis on structure and digestion of waxy rice starch.

    Science.gov (United States)

    Li, Hongyan; Zhu, Yanqiao; Jiao, Aiquan; Zhao, Jianwei; Chen, Xiaoming; Wei, Benxi; Hu, Xiuting; Wu, Chunsen; Jin, Zhengyu; Tian, Yaoqi

    2013-04-01

    The structure and in vitro digestibility of native waxy rice starch by the combined hydrolysis of α-amylase and hydrochloric acid were investigated in this study. The combined hydrolysis technique generated higher hydrolysis rate and extent than the enzymatic hydrolysis. The granular appearance and chromatograph profile demonstrated that α-amylase and hydrochloric acid exhibited different patterns of hydrolysis. The rise in the ratio of absorbance 1047/1022cm(-1), the melting temperature range (Tc-To), and the melting enthalpy (ΔH) were observed during the combined hydrolysis. These results suggest that α-amylase simultaneously cleaves the amorphous and crystalline regions, whereas the amorphous regions of starch granules are preferentially hydrolyzed during the acid hydrolysis. Furthermore, the combined hydrolysis increased rapidly digestible starch (RDS) while decreased slowly digestible starch (SDS) and resistant starch (RS), indicating that the hydrolysis mode affected the digestion property of native waxy rice starch.

  17. Effect of foods and drinks on primary tooth enamel after erosive challenge with hydrochloric acid.

    Science.gov (United States)

    Mesquita-Guimarães, Késsia Suênia Fidelis de; Scatena, Camila; Borsatto, Maria Cristina; Rodrigues-Júnior, Antonio Luiz; Serra, Mônica Campos

    2015-01-01

    The aim of this study was to evaluate the effect of industrialised foods and drinks on primary tooth enamel previously eroded with hydrochloric acid (HCl). The crowns of one hundred two specimens were subjected to an erosive challenge with HCl and randomly divided into six groups (n = 17): Chocolate Milk (Toddynho® - Pepsico) - negative control; Petit Suisse Yogurt (Danoninho® - Danone); Strawberry Yogurt (Vigor); Apple puree (Nestlé); Fermented Milk (Yakult® - Yakult); and Home Squeezed Style Orange Juice (del Valle) - positive control. The 28-day immersion cycles for the test products were performed twice daily and were interspersed with exposure of the test substrate to artificial saliva. Measurements of enamel surface microhardness (SMH) were performed initially, after immersion in HCl and at 7, 14, 21 and 28 days of experimentation. A two-way ANOVA, according to a split-plot design, followed by the sum of squares decomposition and Tukey's test, revealed a significant effect for the interaction between Foods and Drinks and Length of Exposure (p < 0.00001). Orange juice resulted in greater mineral loss of enamel after 28 days. None of the test products was associated with recovery of tooth enamel microhardness.

  18. Two pyrazine derivatives as inhibitors of the cold rolled steel corrosion in hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Deng Shuduan, E-mail: dengshuduan@163.co [Faculty of Wood Science and Decoration Technology, Southwest Forestry University, Kunming 650224 (China); Li Xianghong; Fu Hui [Department of Fundamental Courses, Southwest Forestry University, Kunming 650224 (China)

    2011-02-15

    Research highlights: Two pyrazine derivatives of 2-aminopyrazine (AP) and 2-amino-5-bromopyrazine (ABP) are good inhibitors for the corrosion of steel in 1.0 M HCl solution. The inhibition efficiency follows the order: ABP > AP. The substitution Br of ABP is the additional centre of adsorption and increases the electron density of pyrazine ring, which can facilitate its adsorption on the metal surface. For either ABP or AP, the adsorption obeys Langmuir adsorption isotherm. Both ABP and AP act as mixed-type inhibitors. - Abstract: The inhibition effect of two pyrazine derivatives of 2-aminopyrazine (AP) and 2-amino-5-bromopyrazine (ABP) on the corrosion of cold rolled steel (CRS) in 1.0 M hydrochloric acid (HCl) was studied by weight loss, potentiodynamic polarization curves, and electrochemical impedance spectroscopy (EIS) methods. The results show that both AP and ABP are good inhibitors, and inhibition efficiency follows the order: ABP > AP. The adsorption of each inhibitor on CRS surface obeys Langmuir adsorption isotherm. Potentiodynamic polarization curves show that two pyrazine derivatives act as mixed-type inhibitors. EIS spectra exhibit one capacitive loop and confirm the inhibitive ability.

  19. Effect of foods and drinks on primary tooth enamel after erosive challenge with hydrochloric acid

    Directory of Open Access Journals (Sweden)

    Késsia Suênia Fidelis de MESQUITA-GUIMARÃES

    2015-01-01

    Full Text Available The aim of this study was to evaluate the effect of industrialised foods and drinks on primary tooth enamel previously eroded with hydrochloric acid (HCl. The crowns of one hundred two specimens were subjected to an erosive challenge with HCl and randomly divided into six groups (n = 17: Chocolate Milk (Toddynho® - Pepsico - negative control; Petit Suisse Yogurt (Danoninho® - Danone; Strawberry Yogurt (Vigor; Apple puree (Nestlé; Fermented Milk (Yakult® - Yakult; and Home Squeezed Style Orange Juice (del Valle - positive control. The 28-day immersion cycles for the test products were performed twice daily and were interspersed with exposure of the test substrate to artificial saliva. Measurements of enamel surface microhardness (SMH were performed initially, after immersion in HCl and at 7, 14, 21 and 28 days of experimentation. A two-way ANOVA, according to a split-plot design, followed by the sum of squares decomposition and Tukey’s test, revealed a significant effect for the interaction between Foods and Drinks and Length of Exposure (p < 0.00001. Orange juice resulted in greater mineral loss of enamel after 28 days. None of the test products was associated with recovery of tooth enamel microhardness.

  20. Heavy metal removal from sewage sludge ash by thermochemical treatment with gaseous hydrochloric acid.

    Science.gov (United States)

    Vogel, Christian; Adam, Christian

    2011-09-01

    Sewage sludge ash (SSA) is a suitable raw material for fertilizers due to its high phosphorus (P) content. However, heavy metals must be removed before agricultural application and P should be transferred into a bioavailable form. The utilization of gaseous hydrochloric acid for thermochemical heavy metal removal from SSA at approximately 1000 °C was investigated and compared to the utilization of alkaline earth metal chlorides. The heavy metal removal efficiency increased as expected with higher gas concentration, longer retention time and higher temperature. Equivalent heavy metal removal efficiency were achieved with these different Cl-donors under comparable conditions (150 g Cl/kg SSA, 1000 °C). In contrast, the bioavailability of the P-bearing compounds present in the SSA after thermal treatment with gaseous HCl was not as good as the bioavailability of the P-bearing compounds formed by the utilization of magnesium chloride. This disadvantage was overcome by mixing MgCO(3) as an Mg-donor to the SSA before thermochemical treatment with the gaseous Cl-donor. A test series under systematic variation of the operational parameters showed that copper removal is more depending on the retention time than the removal of zinc. Zn-removal was declined by a decreasing ratio of the partial pressures of ZnCl(2) and water.

  1. Direct anodic hydrochloric acid and cathodic caustic production during water electrolysis

    Science.gov (United States)

    Lin, Hui-Wen; Cejudo-Marín, Rocío; Jeremiasse, Adriaan W.; Rabaey, Korneel; Yuan, Zhiguo; Pikaar, Ilje

    2016-02-01

    Hydrochloric acid (HCl) and caustic (NaOH) are among the most widely used chemicals by the water industry. Direct anodic electrochemical HCl production by water electrolysis has not been successful as current commercially available electrodes are prone to chlorine formation. This study presents an innovative technology simultaneously generating HCl and NaOH from NaCl using a Mn0.84Mo0.16O2.23 oxygen evolution electrode during water electrolysis. The results showed that protons could be anodically generated at a high Coulombic efficiency (i.e. ≥ 95%) with chlorine formation accounting for 3 ~ 5% of the charge supplied. HCl was anodically produced at moderate strengths at a CE of 65 ± 4% together with a CE of 89 ± 1% for cathodic caustic production. The reduction in CE for HCl generation was caused by proton cross-over from the anode to the middle compartment. Overall, this study showed the potential of simultaneous HCl and NaOH generation from NaCl and represents a major step forward for the water industry towards on-site production of HCl and NaOH. In this study, artificial brine was used as a source of sodium and chloride ions. In theory, artificial brine could be replaced by saline waste streams such as Reverse Osmosis Concentrate (ROC), turning ROC into a valuable resource.

  2. Removing hydrochloric acid exhaust products from high performance solid rocket propellant using aluminum-lithium alloy.

    Science.gov (United States)

    Terry, Brandon C; Sippel, Travis R; Pfeil, Mark A; Gunduz, I Emre; Son, Steven F

    2016-11-05

    Hydrochloric acid (HCl) pollution from perchlorate based propellants is well known for both launch site contamination, as well as the possible ozone layer depletion effects. Past efforts in developing environmentally cleaner solid propellants by scavenging the chlorine ion have focused on replacing a portion of the chorine-containing oxidant (i.e., ammonium perchlorate) with an alkali metal nitrate. The alkali metal (e.g., Li or Na) in the nitrate reacts with the chlorine ion to form an alkali metal chloride (i.e., a salt instead of HCl). While this technique can potentially reduce HCl formation, it also results in reduced ideal specific impulse (ISP). Here, we show using thermochemical calculations that using aluminum-lithium (Al-Li) alloy can reduce HCl formation by more than 95% (with lithium contents ≥15 mass%) and increase the ideal ISP by ∼7s compared to neat aluminum (using 80/20 mass% Al-Li alloy). Two solid propellants were formulated using 80/20 Al-Li alloy or neat aluminum as fuel additives. The halide scavenging effect of Al-Li propellants was verified using wet bomb combustion experiments (75.5±4.8% reduction in pH, ∝ [HCl], when compared to neat aluminum). Additionally, no measurable HCl evolution was detected using differential scanning calorimetry coupled with thermogravimetric analysis, mass spectrometry, and Fourier transform infrared absorption. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Inhibition of the corrosion of mild steel in hydrochloric acid by isatin and isatin glycine

    Directory of Open Access Journals (Sweden)

    B.I. Ita

    2006-12-01

    Full Text Available The inhibition of corrosion of mild steel in hydrochloric acid by isatin glycine (ING and isatin (IN at 30-60 oC and concentrations of 0.0001 M to 0.0005 M was studied via weight loss method. At the highest inhibitor concentration studied ING exhibited inhibition efficiency of 87% while IN exhibited 84% at 60 oC. A chemical adsorption mechanism was proposed on the basis of the temperature effect and obtained average activation energy values of 143.9 kJ/mol for ING and 118.5 kJ/mol for IN. The two inhibitors were confirmed to obey the Langmuir adsorption isotherm equation at the concentrations studied. Also a first-order type of mechanism was proposed from the kinetic treatment of the result. The difference in the inhibitory properties of the inhibitors was explained in terms of the difference in their molecular structures and solubility rather than difference in molecular weights alone.

  4. Adsorption of Methylene Blue from Aqueous Solution onto Hydrochloric Acid-modified Rectorite

    Institute of Scientific and Technical Information of China (English)

    ZHANG Gaoke; LIU Guanfeng; GUO Yadan

    2011-01-01

    H+-rectorite clay,which was prepared by modifying the raw rectorite with 10% hydrochloric acid at 60 ℃C for 24 h,was used as an absorbent for removal of methyl blue (MB) from aqueous solutions.The morphology and the structure and crystallinity of the pristine rectorite and the H+-rectorite were characterized by scanning electron microscopy (SEM) technique and X-ray diffraction (XRD) technique,respectively.The results showed that the H+-rectorite exhibited high adsorption ability than the raw rectorite,and it was found that the removal percentage of MB increased with increasing in adsorbents dose,whereas the adsorption amount q,(mg/g) decreased.The equilibrium was attained within 30 min in adsorption process,and the maximum adsorption capacity of H+-rectorite for methylene blue reached as high as 37 mg/g.Besides,the effect of temperature on the adsorption of MB with H+-rectorite was investigated and the equilibrium data were well fitted to Freundlich equations.The H+-rectorite absorbent saturated with MB can be regenerated by calcinating at 400 ℃ for 2 h and the regenerated absorbent still showed higher percentage removal of MB.

  5. Eclipta Alba as Corrosion Pickling Inhibitor on Mild Steel in Hydrochloric Acid

    Institute of Scientific and Technical Information of China (English)

    M. Shyamala; A. Arulanantham

    2009-01-01

    Due to ease of application, cost effectiveness and environmentally safe, in this study, the corrosion inhibition effect of aqueous extract of Eclipta alba in 1 N hydrochloric acid has been investigated by weight loss, potentiodynamic polarization and impedance methods and the extracts of Eclipta alba were found to be effective corrosion pickling inhibitor. The effect of immersion time and temperature revealed that the extracts of Eclipta alba with an optimum concentration of 8.0% v/v showed maximum inhibition efficiency of 99.6% at 3 h immersion time and 30℃. Arrhenius plots for mild steel immersed in 1 N HCI solution in the absence and presence of optimum concentration (8.0% in v/v) of Eclipta alba extract showed the effect of temperature. Polarization studies indicate that this plant extract acts as a mixed type inhibitor. The adsorption of Eclipta alba follows Langmuir adsorption isotherm. The inhibition action may be due to the presence of the Wedelactone and also the alkaloid Ecliptine present in the leaves of Eclipta alba.

  6. Establishment of hydrochloric acid/lipopolysaccharide-induced pelvic inflammatory disease model.

    Science.gov (United States)

    Oh, Yeonsu; Lee, Jaehun; Kim, Hyeon-Cheol; Hahn, Tae-Wook; Yoon, Byung-Il; Han, Jeong-Hee; Kwon, Yong-Soo; Park, Joung Jun; Koo, Deog-Bon; Rhee, Ki-Jong; Jung, Bae Dong

    2016-09-30

    Pelvic inflammatory disease (PID), which is one of the most problematic complications experienced by women with sexually transmitted diseases, frequently causes secondary infections after reproductive abnormalities in veterinary animals. Although the uterus is self-protective, it becomes fragile during periods or pregnancy. To investigate PID, bacteria or lipopolysaccharide (LPS) extracted from gram negative bacteria has been used to induce the disease in several animal models. However, when LPS is applied to the peritoneum, it often causes systemic sepsis leading to death and the PID was not consistently demonstrated. Hydrochloric acid (HCl) has been used to induce inflammation in the lungs and stomach but not tested for reproductive organs. In this study, we developed a PID model in mice by HCl and LPS sequential intracervical (i.c.) administration. The proinflammatory cytokines, interleukin (IL)-1β, IL-6 and tumor necrosis factor-α, were detected in the mouse uterus by western blot analysis and cytokine enzyme-linked immunosorbent assay after HCl (25 mg/kg) administration i.c. followed by four LPS (50 mg/kg) treatments. Moreover, mice exhibited increased infiltration of neutrophils in the endometrium and epithelial layer. These results suggest that ic co-administration of HCl and LPS induces PID in mice. This new model may provide a consistent and reproducible PID model for future research.

  7. Studies on the inhibition of mild steel corrosion in hydrochloric acid solution by atenolol drug

    Directory of Open Access Journals (Sweden)

    G. Karthik

    2016-06-01

    Full Text Available The inhibition performance of atenolol on mild steel in 1 M hydrochloric acid solution was studied by weight loss and electrochemical methods. The results show the inhibition efficiency was found to increase with increasing the concentration of the inhibitor from 50 to 300 ppm. The maximum inhibition efficiency 93.8% was observed in the presence of 300 ppm inhibitor (in case of potentiodynamic polarization. The inhibition action of atenolol was explained in terms of adsorption on the mild steel surface. The adsorption process follows Langmuir isotherm via physical adsorption. Electrochemical Impedance spectroscopic technique (EIS exhibits one capacitive loop indicating that, the corrosion reaction is controlled by charge transfer process. Polarization measurements showed that the inhibitor is of a mixed type. The results obtained from the different methods are in good agreement. The surface morphologies of mild steel were examined by Fourier-transform infrared (FT-IR spectroscopy, scanning electron microscope (SEM. Further, the computational calculations are performed to find a relation between their electronic and structural properties.

  8. Dissolution Process of Palladium in Hydrochloric Acid: A Route via Alkali Metal Palladates

    Science.gov (United States)

    Kasuya, Ryo; Miki, Takeshi; Morikawa, Hisashi; Tai, Yutaka

    2015-12-01

    To improve the safety of the Pd recovery processes that use toxic oxidizers, dissolution of Pd in hydrochloric acid with alkali metal palladates was investigated. Alkali metal palladates were prepared by calcining a mixture of Pd black and alkali metal (Li, Na, and K) carbonates in air. Almost the entire amount of Pd was converted into Li2PdO2 after calcination at 1073 K (800 °C) using Li2CO3. In contrast, PdO was obtained by calcination at 1073 K (800 °C) using Na and K carbonates. Our results indicated that Li2CO3 is the most active reagent among the examined alkali metal carbonates for the formation of palladates. In addition, dissolution of the resulting Li2PdO2 in HCl solutions was evaluated under various conditions. In particular, Li2PdO2 rapidly dissolved in diluted (0.1 M) HCl at ambient temperature. Solubility of Pd of Li2PdO2 was found to be 99 pct or larger after dissolution treatment at 353 K (80 °C) for 5 minutes; in contrast, PdO hardly dissolved in 0.1 M HCl. The dissolution mechanism of Li2PdO2 in HCl was also elucidated by analysis of crystal structures and particulate properties. Since our process is completely free from toxic oxidizers, the dissolution process via alkali metal palladates is much safer than currently employed methods.

  9. The inhibitive effect of bipyrazolic derivatives on the corrosion of steel in hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Tebbji, K. [Laboratoire de Chimie des Eaux et Corrosion, Faculte des Sciences, B.P. 717, Oujda (Morocco); Hammouti, B. [Laboratoire de Chimie des Eaux et Corrosion, Faculte des Sciences, B.P. 717, Oujda (Morocco); Oudda, H. [Laboratoire des Procedes de Separation, Faculte des Sciences, Kenitra (Morocco); Ramdani, A. [Laboratoire de Chimie Organique-Physique, Faculte des Sciences, B.P. 717, Oujda (Morocco); Benkadour, M. [Laboratoire de Chimie des Eaux et Corrosion, Faculte des Sciences, B.P. 717, Oujda (Morocco)

    2005-12-15

    The effect of two pyrazole-type organic compounds, namely ethyl 5,5'-dimethyl-1'H-1,3'-bipyrazole-3 carboxylate (P1) and 3,5,5'-trimethyl-1'H-1,3'-bipyrazole (P2) on the corrosion behaviour of steel in 1 M hydrochloric acid (HCl) solution is investigated at 308 K by weight loss measurements, potentiodynamic polarisation and impedance spectroscopy (EIS) methods. The inhibition efficiencies obtained from cathodic Tafel plots, gravimetric and EIS methods are in good agreement. Results obtained show that the compound P2 is the best inhibitor and its efficiency reaches 84% at 10{sup -3} M. Potentiodynamic polarisation studies show that pyrazolic derivatives are cathodic-type inhibitors and these compounds act on the cathodic reaction without changing the mechanism of the hydrogen evolution reaction. The inhibition efficiency of P2 is temperature-dependent in the range from 308 to 353 K and the associated activation energy has been determined. P2 adsorbs on the steel surface according to Langmuir adsorption model. The calculation of the total partial charge of inhibitor atoms is computed.

  10. The thermal, rheological and structural properties of cassava starch granules modified with hydrochloric acid at different temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Beninca, Cleoci; Colman, Tiago Andre Denck [State University of Ponta Grossa - UEPG, Av. Carlos Cavalcanti, 4748, ZIP 84030-900, Ponta Grossa, PR (Brazil); Lacerda, Luiz Gustavo; Filho, Marco Aurelio Silva Carvalho [Positivo University, Curitiba, PR (Brazil); Bannach, Gilbert [Paulista State University - UNESP, Bauru, SP (Brazil); Schnitzler, Egon, E-mail: egons@uepg.br [State University of Ponta Grossa - UEPG, Av. Carlos Cavalcanti, 4748, ZIP 84030-900, Ponta Grossa, PR (Brazil)

    2013-01-20

    Highlights: Black-Right-Pointing-Pointer Untreated cassava starch was modified with standard hydrochloric acid at 20 and 50 Degree-Sign C by 8 h. Black-Right-Pointing-Pointer DSC curves allowed to verify increase in the gelatinization enthalpy in agreement with high temperature. Black-Right-Pointing-Pointer Pasting properties of the studied starches were inversely proportional to the acid treatment and increased temperature. Black-Right-Pointing-Pointer The morphology of granules as well as average size and average roughness were calculated by NC-AFM. - Abstract: Starch is arguably one of the most actively investigated biopolymer in the world. In this study, the native (untreated) cassava starch granules (Manihot esculenta, Crantz) were hydrolyzed by standard hydrochloric acid solution at different temperatures (30 Degree-Sign C and 50 Degree-Sign C) and the hydrolytic transformations were investigated by the following techniques: simultaneous thermogravimetry-differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), as well as non-contact atomic force microscopy (NC-AFM), X-ray diffraction (XRD) powder patterns, and rapid viscoamylographic analysis (RVA). After the treatment with hydrochloric acid at different temperatures, the thermal stability, a gradual loss of pasting properties (viscosity), alterations in the gelatinization enthalpy ({Delta}H{sub gel}), were observed. The use of NC-AFM and XRD allowed the observation of the surface morphology and topography of the starch granules and changes in crystallinity of the granules, respectively.

  11. The Effect of Temperature and Acid Concentration on Corrosion of Low Carbon Steel in Hydrochloric Acid Media

    Directory of Open Access Journals (Sweden)

    Anees A. Khadom

    2009-01-01

    Full Text Available Problem statement: The effect of different temperatures and acid concentrations on the corrosion of low carbon steel in hydrochloric acid were addressed in this study. Approach: The effect of temperature was explained by application of Arrhenius equation and transition state theory, while the acid concentration effect was explained using reaction kinetic equations. The combined effect of temperature and acid concentration then modeled using a nonlinear regression method. Results: A detail of thermodynamic parameters of activation (E, ΔH* and ΔS* and kinetic studies for the corrosion reaction were obtained. Nonlinear corrosion rates as a function of temperature and acid concentration equation were estimated with a good prediction corrosion rates values. Conclusion: The values of activation energy E and enthalpy of activation ΔH* decrease with increase in acid concentration indicating the increasing in reaction rate. Entropy of activation ΔS* tend to lower values with increasing in acid concentration which indicated that the activated complex was more orderly relative to the initial state. The corrosion reaction was approximately firs order reaction. The observed corrosion rate values from the experimental data were in a good agreement with that predicated by the mathematical equation.

  12. Hydrochloric acid infusion for treatment of metabolic alkalosis associated with respiratory acidosis.

    Science.gov (United States)

    Brimioulle, S; Berre, J; Dufaye, P; Vincent, J L; Degaute, J P; Kahn, R J

    1989-03-01

    Hypercapnia due to respiratory failure can be more severe when accompanied by coexistent metabolic alkalosis. We therefore tested the hypothesis that hydrochloric acid (HCl) infusion could improve PaCO2 in 15 critically ill patients admitted with mixed respiratory acidosis and metabolic alkalosis, and a pH of between 7.35 and 7.45. HCl was infused at a constant rate of 25 mmol/h until the bicarbonate concentration decreased less than 26 mmol/L, or until the pH decreased less than 7.35 (initial pH greater than 7.40) or 7.30 (initial pH less than 7.40). Administration of 170 +/- 53 mmol of HCl decreased the bicarbonate concentration from 34 +/- 3 to 25 +/- 2 mmol/L (p less than .001), the pH from 7.41 +/- 0.03 to 7.33 +/- 0.02 (p less than .001), and the PaCO2 from 54 +/- 8 to 48 +/- 8 torr (p less than .001). Postinfusion PaCO2 could be predicted accurately from the initial status of the patients (r = .95, p less than .001) except in one patient with fixed hypercapnia. PaCO2 increased from 77 +/- 19 to 94 +/- 24 torr (p less than .001) and PaO2/PAO2 increased from 59 +/- 17 to 66 +/- 17% (p less than .001). The effects of HCl were still present 12 h after the end of the infusion. No complications related to the acid infusion were noted. These results indicate that, even in the absence of alkalemia, active correction of metabolic alkalosis by HCl infusion can improve CO2 and oxygen exchange in critically ill patients with mixed respiratory acidosis and metabolic alkalosis.

  13. Removing hydrochloric acid exhaust products from high performance solid rocket propellant using aluminum-lithium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Terry, Brandon C., E-mail: terry13@purdue.edu [School of Aeronautics and Astronautics, Purdue University, Zucrow Laboratories, 500 Allison Rd, West Lafayette, IN 47907 (United States); Sippel, Travis R. [Department of Mechanical Engineering, Iowa State University, 2025 Black Engineering, Ames, IA 50011 (United States); Pfeil, Mark A. [School of Aeronautics and Astronautics, Purdue University, Zucrow Laboratories, 500 Allison Rd, West Lafayette, IN 47907 (United States); Gunduz, I.Emre; Son, Steven F. [School of Mechanical Engineering, Purdue University, Zucrow Laboratories, 500 Allison Rd, West Lafayette, IN 47907 (United States)

    2016-11-05

    Highlights: • Al-Li alloy propellant has increased ideal specific impulse over neat aluminum. • Al-Li alloy propellant has a near complete reduction in HCl acid formation. • Reduction in HCl was verified with wet bomb experiments and DSC/TGA-MS/FTIR. - Abstract: Hydrochloric acid (HCl) pollution from perchlorate based propellants is well known for both launch site contamination, as well as the possible ozone layer depletion effects. Past efforts in developing environmentally cleaner solid propellants by scavenging the chlorine ion have focused on replacing a portion of the chorine-containing oxidant (i.e., ammonium perchlorate) with an alkali metal nitrate. The alkali metal (e.g., Li or Na) in the nitrate reacts with the chlorine ion to form an alkali metal chloride (i.e., a salt instead of HCl). While this technique can potentially reduce HCl formation, it also results in reduced ideal specific impulse (I{sub SP}). Here, we show using thermochemical calculations that using aluminum-lithium (Al-Li) alloy can reduce HCl formation by more than 95% (with lithium contents ≥15 mass%) and increase the ideal I{sub SP} by ∼7 s compared to neat aluminum (using 80/20 mass% Al-Li alloy). Two solid propellants were formulated using 80/20 Al-Li alloy or neat aluminum as fuel additives. The halide scavenging effect of Al-Li propellants was verified using wet bomb combustion experiments (75.5 ± 4.8% reduction in pH, ∝ [HCl], when compared to neat aluminum). Additionally, no measurable HCl evolution was detected using differential scanning calorimetry coupled with thermogravimetric analysis, mass spectrometry, and Fourier transform infrared absorption.

  14. Extraction of trace thorium from hydrochloric acid media by 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone

    Institute of Scientific and Technical Information of China (English)

    YANG Wei-Fan; YUAN Shuang-Gui; XU Yan-Bing; XIAO Yong-Hou; XIONG Bing

    2003-01-01

    The paper describes the solvent extraction of trace thorium from hydrochloric acid media by1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) using a radioactive tracer technique. The percent extraction ofthorium was studied as a function of acidity, PMBP concentration and equilibrium time. The back-extraction behaviorof thorium from the organic phase was also tested. Separation of thorium was performed from fission products pro-duced in 14 MeV neutron bombardment of natural uranium by employing the PMBP extraction procedure. Thegamma-ray spectra of the separated thorium fractions show that thorium can be separated from most of fission prod-ucts and a large amount of uranium.

  15. Content Determination of Hydrochloric Acid Ephedrine and Hydrochloric Acid Pseudoephedrine inTongxuanlifei Granules%通宣理肺颗粒中麻黄碱含量测定方法研究

    Institute of Scientific and Technical Information of China (English)

    肖斯婷; 付欣彤; 常增荣

    2011-01-01

    目的 采用高效液相色谱法测定建立通宣理肺颗粒中盐酸麻黄碱与盐酸伪麻黄碱含量,建立其质量标准.方法 采用Phenomenex Synerg 4u Polar-RP 80A(250mm× 4.6mm,4 μm)色谱柱,流动相:甲醇:0.092%磷酸溶液(含0.04%三乙胺和0.02%二正丁胺)=1:99;检测波长:210 nm.结果 该法测定通宣理肺颗粒中盐酸麻黄碱3个浓度回收率分另为102.44%、100.93%、97.73%,RSD分别为1.30%、0.38%、1.77%(n=3);盐酸伪麻黄碱回收率分别为99.98%、96.01%、100.91%,RSD分别为1.65%、0.65%、1.91%(n=3).本品按标示量计算,含麻黄以盐酸麻黄碱与盐酸伪麻黄碱的总量计0.6 ~3 mg/袋.结论 本方法操作简便,结果可靠,准确,能有效地控制通宣理肺颗粒的质量.%Objective To establish the quality standard for Tongxuanlifei Granules (Hydrochloric acid ephedrine & Hydrochloric acid pseudoephedrine). Methods The contents of Hydrochloric acid ephedrine and Hydrochloric acid pseudoephedrine were determined on the Phenomenex Synerg 4u Polar-RP 80A (250 mm× 4.6 mm, 4 μm) column, with MeOH :0.092% Phosphoric acid solution (with 0.04% Triethylamine and 0.02% Two butyl amine)=l : 99 elution as mobile phase and detective wavelength at 210 nm. Results The average recovery of Hydrochloric acid ephedrine of there concentration was 102.44%, 100.93%, 97.73%, and RSD was 1.30%, 0.38%, 1.77% (n=3). The average recovery of Hydrochloric acid pseudoephedrine was 99.98%, 96.01%, 100.91%, and RSD was 1.65%, 0.65%, 1.91% (n=3). The detection quantity should be within 0.6 - 3 mg labeled weight. Conclusion The method is simple, reliable, accurate and can be applied to the quality control of Tongxuanlifei Granules.

  16. Characterization of Polyamide 66 membranes prepared by phase inversion using formic acid and hydrochloric acid such as solvents

    Directory of Open Access Journals (Sweden)

    Patrícia Poletto

    2011-12-01

    Full Text Available The membranes properties prepared from water/formic acid (FA/ polyamide 66 (PA66 and water/hydrochloric acid (HCl/polyamide 66 (PA 66 systems has been studied. The different solvents interact distinctly with the polymer, affecting the membrane morphology. The asymmetric structure of the membranes showed a dense top layer and a porous sublayer. The membranes M-HCl prepared from HCl/PA 66 system showed a larger dense layer (around 23 μm in compared to those prepared from FA/PA 66 system (M-FA (around 10 μm. The membrane morphology was a determinant factor in results of water absorption, porosity and pure water flux. The lower thickness of dense layer in M-FA membranes resulted in a higher water absorption and, consequently, porosity, approximately 50%, compared with M-HCl membranes, approximately 15%. The same trend was observed to permeate flux, the lower thickness of dense layer higher pure water flux.

  17. Thermal decomposition of ethylenediaminetetraacetic acid in the presence of 1,2-phenylenediamine and hydrochloric acid

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jingwen [Yancheng Institute of Technology, Yancheng (China); Gao, Jinhao [Nanjing Univ., Nanjing (China). Coordination Chemistry Institute. State Key Lab. of Coordination Chemistry; Wang, Xiaoyong [Nanjing Univ., Nanjing (China). School of Life Science. State Key Lab. of Pharmaceutical Biotechnology]. E-mail: boxwxy@nju.edu.cn

    2006-09-15

    Based on the reaction products of ethylenediaminetetraacetic acid (EDTA) with 1,2- phenylenediamine (o-PDA), a novel thermal decomposition pathway of EDTA is proposed. The strong acidic medium and the presence of o-PDA facilitate the decomposition of EDTA as evidenced by the relatively lower reaction temperature. In addition to the steps described in literatures, rearrangement process is involved in the decomposition reaction. The rearranged intermediates condense with o-PDA, forming an unexpected biologically active compound 2,2,4- trimethyl-3H-5-hydro-1,5-benzodiazepine, thus provides the possibility to explore an alternative decomposition mechanism for this widely used chelator. (author)

  18. The effects of pharmaceutically active compound doxycycline on the corrosion of mild steel in hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Shukla, Sudhish Kumar [Department of Applied Chemistry, Institute of Technology, Banaras Hindu University, Varanasi 221 005, Uttar Pradesh (India); Quraishi, M.A. [Department of Applied Chemistry, Institute of Technology, Banaras Hindu University, Varanasi 221 005, Uttar Pradesh (India)], E-mail: maquraishi.apc@itbhu.ac.in

    2010-02-15

    Corrosion inhibition of mild steel in hydrochloric acid solution by doxycycline has been studied by weight loss measurements, polarization resistance, Tafel polarization and electrochemical impedance spectroscopy. The inhibitor showed more than 95% inhibition efficiency at optimum concentration 9.02 x 10{sup -4} M. Potentiodynamic polarization suggests that it is a mixed type of inhibitor. Electrochemical impedance spectroscopy was used to investigate the mechanism of corrosion inhibition. Thermodynamic parameters were calculated to investigate mechanism of inhibition. The compound follows Langmuir adsorption isotherm. AFM studies of mild steel surface with and without inhibitor were performed and calculated roughness also supported the inhibition data.

  19. Leaching lithium from the anode electrode materials of spent lithium-ion batteries by hydrochloric acid (HCl).

    Science.gov (United States)

    Guo, Yang; Li, Feng; Zhu, Haochen; Li, Guangming; Huang, Juwen; He, Wenzhi

    2016-05-01

    Spent lithium-ion batteries (LIBs) are considered as an important secondary resource for its high contents of valuable components, such as lithium and cobalt. Currently, studies mainly focus on the recycling of cathode electrodes. There are few studies concentrating on the recovery of anode electrodes. In this work, based on the analysis result of high amount of lithium contained in the anode electrode, the acid leaching process was applied to recycle lithium from anode electrodes of spent LIBs. Hydrochloric acid was introduced as leaching reagent, and hydrogen peroxide as reducing agent. Within the range of experiment performed, hydrogen peroxide was found to have little effect on lithium leaching process. The highest leaching recovery of 99.4wt% Li was obtained at leaching temperature of 80°C, 3M hydrochloric acid and S/L ratio of 1:50g/ml for 90min. The graphite configuration with a better crystal structure obtained after the leaching process can also be recycled.

  20. Corrosion and Inhibition Effects of Mild Steel in Hydrochloric Acid Solutions Containing Organophosphonic Acid

    Directory of Open Access Journals (Sweden)

    Manish Gupta

    2013-01-01

    Full Text Available A study has been made on the mechanism of corrosion of mild steel and the effect of nitrilo trimethylene phosphonic (NTMP acid as a corrosion inhibitor in acidic medium, that is, 10% HC1 using the weight loss method and electrochemical techniques, that is, potentiodynamic and galvanostatic polarization measurements. Although corrosion is a long-time process, but it takes place at a faster rate in the beginning which goes on decreasing with due course of time. The above-mentioned methods of corrosion rate determination furnish an average value for a long-time interval. Looking at the versatility and minimum detection limit of the voltammetric method, the authors have developed a new voltammetric method for the determination of corrosion rate at short-time intervals. The results of corrosion of mild steel in 10% HC1 solution with and without NTMP inhibitor at short-time intervals have been reported. The corrosion inhibition efficiency of NTMP is 93% after 24 h.

  1. Separation of metal ions by anion exchange in mixtures of hydrochloric acid and hydrofluoric acid

    Energy Technology Data Exchange (ETDEWEB)

    Faris, J.P.

    1978-12-01

    Distribution coefficients were determined for the adsorption of more than 40 elements on anion-exchange resins from mixtures of HCl (0.1 to 12M) and HF (0.1-8M). Two resins, Dowex 1 x 10, 200 to 400 mesh and Dowex 1 x 4, 100 to 200 mesh, were used. Distribution coefficients were also determined for the adsorption of many elements on both resins from 0.1 to 12M HCl and 0.1 to 12M HF. Anion exchange in the presence of HF was found useful for separating impurities from various materials for their subsequent determination, and specific procedures used in our spectrochemical laboratory for this purpose are outlined. The results of a literature search on the use of anion exchange in hydrofluoric acid and fluoride-containing media are presented in an extensive bibliography. 404 references, 9 tables.

  2. Analysis on a cracking accident of hydrochloric acid storage tank caused by vacuum%稀盐酸储槽抽裂事故的分析

    Institute of Scientific and Technical Information of China (English)

    王欣荣

    2012-01-01

    分析了盐酸脱吸工序中稀盐酸储槽抽裂事故产生的原因;通过稀盐酸储槽的压力式液位计DCS历史曲线记录来间接分析稀盐酸储槽内压力变化情况,剖析负压的形成过程。结果表明:脱吸塔产生较大的负压是因为系统急停、温度下降后在略低于盐酸溶液恒沸点时发生冷凝相变而引起的。%Reasons for a cracking accident of hydrochloric acid storage tank caused by vacuum in hydrochloric acid desorption process were analyzed. Pressure changes inside dilute hydrochloric acid storage tank were indirectly analyzed according to DCS historical graph record of the pressure type level meter for the hydrochloric acid storage tank, and the negative pressure formation process was also discussed. The results showed that the formation of large negative pressure in desorption col- umn was caused by phase transition of condensation occurred whlie the temperature of system was a little less than the constant boiling point of hydrochloric acid solution, which was caused by emer- gency shutdown of system and temperature falling.

  3. Growth and membrane fluidity of food-borne pathogen Listeria monocytogenes in the presence of weak acid preservatives and hydrochloric acid

    Directory of Open Access Journals (Sweden)

    Ioannis eDiakogiannis

    2013-06-01

    Full Text Available This study addresses a major issue in microbial food safety, the elucidation of correlations between acid stress and changes in membrane fluidity of the pathogen Listeria monocytogenes. In order to assess the possible role that membrane fluidity changes play in L. monocytogenes tolerance to antimicrobial acids (acetic, lactic, hydrochloric acid at low pH or benzoic acid at neutral pH, the growth of the bacterium and the gel-to-liquid crystalline transition temperature point (Tm of cellular lipids of each adapted culture was measured and compared with unexposed cells. The Tm of extracted lipids was measured by Differential Scanning Calorimetry (DSC. A trend of increasing Tm values but not of equal extent was observed upon acid tolerance for all samples and this increase is not directly proportional to each acid antibacterial action. The smallest increase in Tm value was observed in the presence of lactic acid, which presented the highest antibacterial action. In the presence of acids with high antibacterial action such as acetic, hydrochloric acid or low antibacterial action such as benzoic acid, increased Tm values were measured. The Tm changes of lipids were also correlated with our previous data about fatty acid changes to acid adaptation. The results imply that the fatty acid changes are not the sole adaptation mechanism for decreased membrane fluidity (increased Tm. Therefore, this study indicates the importance of conducting an in-depth structural study on how acids commonly used in food systems affect the composition of individual cellular membrane lipid molecules.

  4. Corrosion inhibition of C38 steel in 1 M hydrochloric acid medium by alkaloids extract from Oxandra asbeckii plant

    Energy Technology Data Exchange (ETDEWEB)

    Lebrini, M. [Laboratoire Materiaux et Molecules en Milieu Amazonien, CNRS 8172-UMR ECOFOG, Campus Trou Biran, Cayenne 97337, French Guiana (France); Robert, F.; Lecante, A. [Laboratoire Materiaux et Molecules en Milieu Amazonien, UAG-UMR ECOFOG, Campus Trou Biran, Cayenne 97337, French Guiana (France); Roos, C., E-mail: christophe.roos@guyane.univ-ag.f [Laboratoire Materiaux et Molecules en Milieu Amazonien, UAG-UMR ECOFOG, Campus Trou Biran, Cayenne 97337, French Guiana (France)

    2011-02-15

    Research highlights: The inhibition effect of alkaloid extract of Oxandra asbeckii plant on the corrosion of C38 steel in 1 M hydrochloric acid solution has been investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Oxandra asbeckii extract examined acted as an efficient corrosion inhibitor in 1 M HCl. Polarization studies showed that Oxandra asbeckii extract was a mixed-type inhibitor and its inhibition efficiency increased with the inhibitor concentration. - Abstract: The inhibition effect of alkaloids extract from Oxandra asbeckii plant (OAPE) on the corrosion of C38 steel in 1 M hydrochloric acid solution has been investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The corrosion inhibition efficiency increases on increasing plant extracts concentration. Cathodic and anodic polarization curves show that OAPE is a mixed-type inhibitor. The effect of temperature on the corrosion behavior of C38 steel in 1 M HCl with and without addition of plant extract was studied in the temperature range 25-55 {sup o}C. The thermodynamic functions of dissolution and adsorption processes were calculated from experimental polarization data and the interpretation of the results are given. The adsorption of this plant extract on the C38 steel surface obeys the Langmuir adsorption isotherm. Surface analysis (Raman) was also carried out to establish the corrosion inhibitive property of this plant extract in HCl solution.

  5. Hydrochloric acid alters the effect of L-glutamic acid on cell viability in human neuroblastoma cell cultures.

    Science.gov (United States)

    Croce, Nicoletta; Bernardini, Sergio; Di Cecca, Stefano; Caltagirone, Carlo; Angelucci, Francesco

    2013-07-15

    l-Glutamic acid (l-glutamate) is used to induce excitotoxicity and test neuroprotective compounds in cell cultures. However, because l-glutamate powder is nearly insoluble in water, many manufacturers recommend reconstituting l-glutamate in hydrochloric acid (HCl) prior to successive dilutions. Nevertheless, HCl, even at low concentrations, may alter the pH of the cell culture medium and interfere with cell activity. Thus, the aim of this study was to evaluate whether the reconstitution of l-glutamate powder in HCl alters its capacity to induce neurotoxicity in different human neuroblastoma cell lines. SH-SY5Y, IMR-32 and SK-N-BE(2) cells were exposed to various concentrations of l-glutamate, which was either reconstituted in HCl (1M) or post re-equilibrated to the pH of the culture medium (7.5). After 24 and 48h of incubation, changes in the cell viability of treated versus untreated cells were evaluated. The effect of an identical amount of HCl present in the l-glutamate dilutions on neuroblastoma cell survival was also investigated. Our data showed that the neurotoxicity of glutamate reconstituted in HCl was comparable to that of HCl alone. Moreover, the pH variations induced by glutamate or HCl in the culture medium were similar. When the pH of the glutamate stock solution was re-equilibrated, l-glutamate induced variation in cell viability to a lower extent and after a longer incubation time. This study demonstrated that HCl used to reconstitute l-glutamate powder might alter the effect of glutamate itself in neuroblastoma cell cultures. Thus, this information might be useful to scientists who use l-glutamate to induce excitotoxicity or to test neuroprotective agents.

  6. Selective liquid-liquid extraction of antimony(III from hydrochloric acid media by N-n-octylaniline in xylene

    Directory of Open Access Journals (Sweden)

    M. A. ANUSE

    2004-04-01

    Full Text Available N-n-Octylaniline in xylene was used for the extraction separation of antimony(III from hydrochloric acid media. Antimony(III was extracted quantitatively with 10 mL 4 % N-n-octylaniline in xylene. It was stripped from the organic phase with 0.5 M ammonia and estimated photometrically by the iodide method. The effect of metal ion, acid, reagent concentration and various foreign ions was investigated. The method affords binary and ternary separation of antimony(III from tellurium(IV, selenium(IV, lead(II, bismuth(III, tin(IV, germanium(IV, copper(II, gold(III, iron(III and zinc(II. The method is applicable for the analysis of synthetic mixtures, alloys and semiconductor thin films. It is fast, accurate and precise.

  7. A Study of N,N-Diethylammonium O,O′-Di(p-methoxyphenyldithiophosphate as New Corrosion Inhibitor for Carbon Steel in Hydrochloric Acid Solution

    Directory of Open Access Journals (Sweden)

    Chuan Lai

    2016-01-01

    Full Text Available N,N-Diethylammonium O,O′-di(p-methoxyphenyldithiophosphate (EAPP as a new corrosion inhibitor was synthesized in the present work. The corrosion inhibition of EAPP in hydrochloric acid for carbon steel was evaluated by potentiodynamic polarization measurements, electrochemical impedance spectroscopy, weight loss measurements, and scanning electron microscopy. The results indicate that the EAPP is mixed type inhibitor, and the adsorption of EAPP on carbon steel surface obeys Langmuir isotherm. In addition, the inhibition efficiency increases with increasing the concentration of inhibitor and decreases with increasing the hydrochloric acid concentration, temperature, and storage time.

  8. Hydrodechlorination of Silicon Tetrachloride to Trichlorosilane Over Ordered Mesoporous Carbon Catalysts: Effect of Pretreatment of Oxygen and Hydrochloric Acid.

    Science.gov (United States)

    Kwak, Do-Hwan; Akhtar, M Shaheer; Kim, Ji Man; Yang, O Bong

    2016-02-01

    This paper reports on the catalytic reaction for the conversion of silicon tetrachloride (STC) to trichlorosilane (TCS) over pretreated ordered mesoporous carbon (OMC) catalysts by oxygen (denoted as OMC-O2) and hydrochloric acid (denoted as OMC-HCl) at 300 degrees C under N2 atmosphere. The OMC-O2 shows significantly improved the surface area (1341.2 m2/g) and pore volume (1.65 cm3/g), which results in the highest conversion rate of 7.3% as compared to bare OMC (4.3%) and OMC-HCI (5.7%). It is found that the conversion rate of STC to TCS is proportional to the number of Si-O bond over OMC catalysts, which suggests that Si-O-C bond formation is crucial to the reaction as active sites. The O2 pretreatment seems to promote the generation of oxygenated species for the formation of Si-O-C.

  9. Electrochemical study on inhibitory effect of Aspirin on mild steel in 1 M hydrochloric acid

    Directory of Open Access Journals (Sweden)

    B.M. Prasanna

    2017-02-01

    Full Text Available Aspirin was investigated as a good corrosion inhibitor for mild steel in 1 M hydrochloric acid at a temperature region from 303 to 333 K. The computed inhibition efficiency increases by increasing the inhibitor concentration and decreases by increasing the temperature. The investigation was done by weight loss, electrochemical measurements such as Tafel polarization and electrochemical impedance spectroscopy. Inhibition effect is attributed to the adsorption of inhibitor on the surface of the mild steel. The Tafel method reveals that the Aspirin acts as a mixed type inhibitor. Activation parameters suggest that the adsorption process is exothermic in nature. SEM photographs of mild steel in the absence and presence of inhibitor visualize the adsorption layer on the surface of the mild steel.

  10. Growth and membrane fluidity of food-borne pathogen Listeria monocytogenes in the presence of weak acid preservatives and hydrochloric acid.

    Science.gov (United States)

    Diakogiannis, Ioannis; Berberi, Anita; Siapi, Eleni; Arkoudi-Vafea, Angeliki; Giannopoulou, Lydia; Mastronicolis, Sofia K

    2013-01-01

    This study addresses a major issue in microbial food safety, the elucidation of correlations between acid stress and changes in membrane fluidity of the pathogen Listeria monocytogenes. In order to assess the possible role that membrane fluidity changes play in L. monocytogenes tolerance to antimicrobial acids (acetic, lactic, hydrochloric acid at low pH or benzoic acid at neutral pH), the growth of the bacterium and the gel-to-liquid crystalline transition temperature point (T m) of cellular lipids of each adapted culture was measured and compared with unexposed cells. The T m of extracted lipids was measured by differential scanning calorimetry. A trend of increasing T m values but not of equal extent was observed upon acid tolerance for all samples and this increase is not directly proportional to each acid antibacterial action. The smallest increase in T m value was observed in the presence of lactic acid, which presented the highest antibacterial action. In the presence of acids with high antibacterial action such as acetic, hydrochloric acid or low antibacterial action such as benzoic acid, increased T m values were measured. The T m changes of lipids were also correlated with our previous data about fatty acid changes to acid adaptation. The results imply that the fatty acid changes are not the sole adaptation mechanism for decreased membrane fluidity (increased T m). Therefore, this study indicates the importance of conducting an in-depth structural study on how acids commonly used in food systems affect the composition of individual cellular membrane lipid molecules.

  11. [Butanol extraction combined with dilute hydrochloric acid dissolution-atomic fluorescence spectrometric method for indirect determination of molybdenum in Chinese herbal medicine].

    Science.gov (United States)

    Lu, Jian-Ping; Geng, Guo-Xing; Tang, Yan-Kui; Lu, Zhi-Yong

    2012-12-01

    A method for indirectly determining the molybdenum in Chinese herbal medicine by butanol extraction and dilute hydrochloric acid dissolution was established for atomic fluorescence spectrometry. The molybdoarsenate heteropoly acid, formed in the presence of As(V) and ammonium molybdate in 0.3 mol x L(-1) sulphuric acid medium, was separated and enriched in the organic solvent, then the evaporation of organic reagent was implemented and the left residue was dissolved in dilute hydrochloric acid in which the arsenic content was determined on behalf of molybdenum. In the optimum experimental conditions, molybdenum content in 0-15 microg x L(-1) range depicts a good linear relationship, the detection limit and relative standard deviation of 0.44 microg x L(-1) and 1.1% were obtained, respectively. Spiked Chinese herbal medicine samples were determined with the proposed method, and recoveries of 95.6%-101.3% were achieved.

  12. A New Solid Sorbent System for Rapid Monitoring of Dehydrogenated Nicotine by Using Furfural-hydrochloric Acid

    Institute of Scientific and Technical Information of China (English)

    B. AMBADE; E. K. JANGHEL; M. K. RAI; G. L. MUNDHARA

    2006-01-01

    A new solid sorbent system is developed for the monitoring of dehydrogenated nicotine in the environment. The reagent system for the indicator tube consists of furfural-hydrochloric acid and phosphoric acid impregnated over a cellulose fibre (cotton) and a humectant calcium chloride. The reagent system has also been used for the preparation of reagent paper. After exposing the indicator tubes and test paper to dehydrogenated nicotine, for a constant time, the red-violet colour developed could be compared with those obtained from standards. Alternatively the coloured compound was extracted in water and the absorbance measured at 540 nm. The lower limit of detection is 0.03 μg/m3 of nicotine for the reagent papers and indicator tubes. The lower limit of determination by spectrophotometric procedure is 0.001 μg/m3 of air.The preparation of indicator tubes, test papers and their applications for the detection and determination of nicotine in environmental tobacco smoke (ETS), mainstream smoke (MS), side stream smoke (SS) and biological samples is described in this paper.

  13. The influence of long term use of inhibitors in hydrochloric acid pickling baths on hydrogen induced stress corrosion cracking

    Energy Technology Data Exchange (ETDEWEB)

    Feser, R.; Friedrich, A.; Scheide, F. [Fachhochschule Suedwestfalen, University of Applied Science, Frauenstuhlweg 31, D-58644 Iserlohn (Germany)

    2002-09-01

    The influence of commercially available inhibitors on the absorption of hydrogen by steel (St 52, StE 460, StE 690, 42CrMo4) in 15% hydrochloric acid was studied. The pickling bath aged continuously due to the chemical reaction with oxidized steel sheets. The H{sup +}- and inhibitor concentration decreased with time. The influence of this ageing process on hydrogen-induced stress corrosion cracking was tested by in-situ tensile tests in the bath solution. With increasing ageing of the bath, the reduction in fracture area was reduced and approached the values measured for non-inhibited acid baths. Furthermore hydrogen permeation was investigated. Permeation current densities rose with increasing ageing of the pickling solution. (Abstract Copyright[2002], Wiley Periodicals, Inc.) [German] Der Einfluss von kommerziell erhaeltlichen Inhibitoren auf die Wasserstoffabsorption von Stahl (St 52, StE 460, StE 690, 42CrMo4) wurde in Salzsaeure untersucht. Die Beizbaeder wurden kontinuierlich durch die chemische Reaktion mit oxidierten Stahlblechen gealtert. Die H{sup +}- und Inhibitorkonzentration nahm mit der Zeit ab. Der Einfluss dieses Alterungsprozesses auf die wasserstoffinduzierte Spannungsrisskorrosion wurde durch in-situ Zugversuche mit Badloesung untersucht. Mit zunehmender Alterung des Bades nahm die Brucheinschnuerung ab und erreichte Werte wie sie auch in der nicht inhibierten Saeure erreicht werden. Weiterhin wurde die Wasserstoff-Permeation untersucht. Die Permeationsstromdichte steigt mit zunehmender Alterung der Beizloesung. (Abstract Copyright[2002], Wiley Periodicals, Inc.)

  14. Interaction between amylose and 1-butanol during 1-butanol-hydrochloric acid hydrolysis of normal rice starch.

    Science.gov (United States)

    Hu, Xiuting; Wei, Benxi; Zhang, Bao; Li, Hongyan; Xu, Xueming; Jin, Zhengyu; Tian, Yaoqi

    2013-10-01

    The aim of this study was to examine the interaction between amylose and 1-butanol during the 1-butanol-hydrochloric acid (1-butanol-HCl) hydrolysis of normal rice starch. The interaction model between amylose and 1-butanol was proposed using gas chromatography-mass spectrometry (GC-MS), (13)C cross polarization and magic angle spinning NMR analysis ((13)C CP/MAS NMR), differential scanning calorimetry (DSC), and thermalgravimetric analysis (TGA). GC-MS data showed that another form of 1-butanol existed in 1-butanol-HCl-hydrolyzed normal rice starch, except in the form of free molecules absorbed on the starch granules. The signal of 1-butanol-HCl-hydrolyzed starch at 100.1 ppm appeared in the (13)C CP/MAS NMR spectrum, indicating that the amylose-1-butanol complex was formed. DSC and TGA data also demonstrated the formation of the complex, which significantly affected the thermal properties of normal rice starch. These findings revealed that less dextrin with low molecular weight formed might be attributed to resistance of this complex to acid during 1-butanol-HCl hydrolysis.

  15. Preliminary study on concrete corrosion of hydrochloric acid%盐酸对混凝土的腐蚀研究

    Institute of Scientific and Technical Information of China (English)

    焦瑞敏

    2011-01-01

    In this paper,ordinary Portland cement concrete and modified concrete were corroded by hydrochloric acid which pH=1.After 60 days of corrosion,the cube compressive strength of every sample is reduced in different degree,from which we can know that amount of fly ash and fume can increase the resistance ability to acid corrosion to some degree but the styrene-butadiene latices reduced this ability of concrete.%对普通硅酸盐水泥混凝土以及改性混凝土进行pH=1的盐酸腐蚀,在腐蚀60d后,各种混凝土的立方体抗压强度均有不同程度的降低。适量的粉煤灰和硅灰可以一定程度地提高混凝土的抗酸性腐蚀性能,而丁苯胶乳的加入却会降低混凝土的这种抗酸性腐蚀性能。

  16. Electrochemical and quantum chemical studies of new thiadiazole derivatives adsorption on mild steel in normal hydrochloric acid medium

    Energy Technology Data Exchange (ETDEWEB)

    Lebrini, M. [Laboratoire de Cristallochimie et Physicochimie du Solide, CNRS UMR 8012, ENSCL, B.P. 108, F-59652 Villeneuve d' Ascq Cedex (France); Lagrenee, M. [Laboratoire de Cristallochimie et Physicochimie du Solide, CNRS UMR 8012, ENSCL, B.P. 108, F-59652 Villeneuve d' Ascq Cedex (France); Vezin, H. [Laboratoire de Chimie Organique et Macromoleculaire, CNRS UMR 8009, USTL Bat C3, F-59655 Villeneuve d' Ascq Cedex (France); Gengembre, L. [Laboratoire de Catalyse Heterogene et Homogene, CNRS UMR 8010, Bat C3, USTL, F-59655 Villeneuve d' Ascq Cedex (France); Bentiss, F. [Laboratoire de Cristallochimie et Physicochimie du Solide, CNRS UMR 8012, ENSCL, B.P. 108, F-59652 Villeneuve d' Ascq Cedex (France)]. E-mail: f.bentiss@pop.ensc-lille.fr

    2005-02-01

    In this work, a new class of thiadiazole derivatives, namely 3,5-bis(2-thienyl)-1,3,4-thiadiazole (2-TTH) and 3,5-bis(3-thienyl)-1,3,4-thiadiazole (3-TTH), have been studied as possible corrosion inhibitors for mild steel in molar hydrochloric acid (1 M HCl). Weight loss measurements, polarisation curves and AC impedance methods have been used. These studies have shown that the thiadiazole derivatives were very good inhibitors for mild steel in 1 M HCl. Comparison of results showed that 3-TTH was the best inhibitor. The potential of zero charge (PZC) of mild steel was studied by AC impedance method, and the mechanism of adsorption has been predicted. X-ray photoelectron spectroscopy surface analysis with thiadiazole derivatives shows that it chemisorbed at the mild steel/HCl interface. The adsorption of these inhibitors followed Langmuir's adsorption isotherm. The electronic properties of 2-TTH and 3-TTH, obtained using the AM1 semi-empirical quantum chemical approach, were correlated with their experimental efficiencies using the linear resistance model (LR). These inhibitors are considered as non-cytotoxic substances.

  17. Enhanced corrosion resistance of mild steel in hydrochloric acid solution by new thiadiazole derivatives: Electrochemical, theoretical and XPS studies

    Energy Technology Data Exchange (ETDEWEB)

    Bentiss, Fouad; Lebrini, Mounim; Lagrenee, Michel [Laboratoire de Cristallochimie et Physicochimie du Solide, CNRS UMR 8012, ENSCL, BP. 108, F-59652 Villeneuve d' Ascq Cedex (France); Herve, Vezin [Laboratoire de Chimie Organique et Macromoleculaire, CNRS UMR 8009, USTL Bat C3, F-59655 Villeneuve d' Ascq Cedex (France)

    2004-07-01

    In this work, a new class of thiadiazole derivatives, namely 3,5-bis(2-thienyl)-1,3,4-thiadiazole (2-TTH) and 3,5-bis(3-thienyl)-1,3,4-thiadiazole (3-TTH), have been studied as possible corrosion inhibitors for mild steel in molar hydrochloric acid (1M HCl). Polarisation curves and AC impedance methods have been used. These studies have shown that the thiadiazole derivatives were very good inhibitors for mild steel in 1M HCl. Comparison of results showed that 3-TTH was the best inhibitor. The potential of zero charge (PZC) of mild steel was studied by ac impedance method, and the mechanism of adsorption has been predicted. X-ray photoelectron spectroscopy surface analysis with thiadiazole derivatives shows that it chemisorbed at the mild steel/HCl interface. The adsorption of these inhibitors followed Langmuir's adsorption isotherm. The electronic properties of 2-TTH and 3-TTH, obtained using the AM1 semi-empirical quantum chemical approach, were correlated with their experimental efficiencies using the linear resistance model (LR). (authors)

  18. Electrochemical and theoretical investigation on the corrosion inhibition of mild steel by thiosalicylaldehyde derivatives in hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Behpour, M. [Department of Chemistry, Faculty of Science, University of Kashan, Kashan (Iran, Islamic Republic of)], E-mail: m.behpour@kashanu.ac.ir; Ghoreishi, S.M.; Soltani, N.; Salavati-Niasari, M.; Hamadanian, M.; Gandomi, A. [Department of Chemistry, Faculty of Science, University of Kashan, Kashan (Iran, Islamic Republic of)

    2008-08-15

    Inhibitory effect of three Schiff bases 2-{l_brace}[(2-sulfanylphenyl)imino]methyl{r_brace}]phenol (A), 2-{l_brace}[(2)-1-(4-methylphenyl)methylidene]amino{r_brace}-1-benznethiol (B), and 2-[(2-sulfanylphen-yl)ethanimidoyl)]phenol (C) on corrosion of mild steel in 15% HCl solution has been studied using weight loss measurements, polarization and electrochemical impedance spectroscopy (EIS) methods. The results of the investigation show that the compounds A and B with mean efficiency of 99% at 200 mg/L additive concentration have fairly good inhibiting properties for mild steel corrosion in hydrochloric acid, and they are as mixed inhibitor. All measurements show that inhibition efficiencies increase with increase in inhibitor concentration. This reveals that inhibitive actions of inhibitors were mainly due to adsorption on mild steel surface. Adsorption of these inhibitors follows the Langmuir adsorption isotherm. Thermodynamic adsorption parameters (K{sub ads}, {delta}G{sub ads}) of studied Schiff bases were calculated using the Langmuir adsorption isotherm. Activation parameters of the corrosion process such as activation energies, E{sub a}, activation enthalpies, {delta}H{sup *}, and activation entropies, {delta}S{sup *}, were calculated by the obtained corrosion currents at different temperatures. Obvious correlation was found between the corrosion inhibition efficiency and the calculated parameters. The obtained theoretical results have been adapted with the experimental data.

  19. Inhibition of Aluminium Corrosion in Hydrochloric Acid Using Nizoral and the Effect of Iodide Ion Addition

    Directory of Open Access Journals (Sweden)

    I. B. Obot

    2010-01-01

    Full Text Available The effect of nizoral (NZR on the corrosion inhibition of aluminium alloy AA 1060 in 2 M HCl solution was investigated using the mylius thermometric technique. Results of the study revealed that nizoral acts as corrosion inhibitor for aluminium in the acidic medium. In general, at constant acid concentration, the inhibition efficiency increases with increase in the inhibitor concentration. The addition of KI to the inhibitor enhanced the inhibition efficiency to a considerable extent. The adsorption of nizoral onto the aluminium surface was found to obey the Fruendlich adsorption isotherm. The value of the free energy for the adsorption process shows that the process is spontaneous.

  20. N-methyl-2-(2-nitrobenzylidene) hydrazine carbothioamide-A new corrosion inhibitor for mild steel in 1 mol·L-1 hydrochloric acid

    Institute of Scientific and Technical Information of China (English)

    K Krishnaveni; K Sampath; J Ravichandran; C Jayabalakrishnan

    2015-01-01

    The corrosion inhibition of mild steel in 1 mol·L−1 hydrochloric acid by N-methyl-2-(2-nitrobenzylidene) hydrazine carbothioamide (MNBHC) was studied using weight loss and electrochemical studies. Results obtained indicate that the inhibitor is effective in hydrochloric acid medium and the efficiency decreases with increase in temperature. Added halide additives improve the efficiency of the inhibitor. The AC impedance studies reveal that the process of inhibition is through charge transfer. Polarization studies indicate the mixed nature of the in-hibitor. From the thermodynamic, spectral and surface analyses the nature of adsorption has been found out. The adsorption of the inhibitor on mild steel follows the Langmuir isotherm.

  1. Extraction of Gold(III) from Hydrochloric Acid Solutions with a PVC-based Polymer Inclusion Membrane (PIM) Containing Cyphos® IL 104

    OpenAIRE

    2015-01-01

    Abstract: Poly(vinyl chloride) (PVC) based polymer inclusion membranes (PIMs), with different concentrations of Cyphos® IL 104 as the membrane extractant/carrier, were studied for their ability to extract Au(III) from hydrochloric acid solutions. Some of the PIMs also contained one of the following plasticizers or modifiers: 2-nitrophenyloctyl ether, dioctylphthalate, 1-dodecanol, 1-tetradecanol, or tri(2-ethylhexyl) phosphate. The best performance, in terms of extraction rate and amount of A...

  2. Effect of ethylenediamine tetraacetic acid disodium on the corrosion of cold rolled steel in the presence of benzotriazole in hydrochloric acid

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Qing [Department of Chemistry, Yunnan University, Kunming 650091 (China)]. E-mail: quqing58@yahoo.com.cn; Jiang, Shuan [Department of Chemistry, Yunnan University, Kunming 650091 (China); Bai, Wei [Department of Chemistry, Yunnan Nationalities University, Kunming 650092 (China); Li, Lei [Laboratory for Conservation and Utilization of Bio-Resources, Yunnan University, Kunming 650091 (China)

    2007-08-01

    The inhibition behavior of cold rolled steel in 0.1 M hydrochloric acid (HCl) by ethylenediamine tetraacetic acid disodium (EDTA) in the absence and presence of benzotriazole (BTA) was investigated with Tafel polarization curve and electrochemical impedance spectroscopy (EIS). The polarization curve results show that the single EDTA acts as an anodic type inhibitor while the combination of EDTA and BTA acts as mixed type inhibitor and mainly inhibits anodic reaction. All impedance spectra in EIS tests exhibit one capacitive loop which indicates that the corrosion reaction is controlled by charge transfer process. Inhibition efficiencies obtained from Tafel polarization, charge transfer resistance (R {sub t}) are consistent. The corrosion of cold rolled steel in 0.1 M HCl is obviously reduced by EDTA in combination with lower concentrations of BTA. Fourier transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM) were used to characterize the corrosion surface of cold rolled steel. Probable mechanisms are present to explain the experimental results.

  3. Effect of triamcinolone acetonide ammonia bromine joint hydrochloric acid on patients with secretory otitis media and on body's inflammatory factor and cellular immunologic parameters

    Institute of Scientific and Technical Information of China (English)

    Quan-Fu Hu; Shao-Ji Ouyang; Rong-Wei Yao; Xue-Jiang Xu; Jin-Hua He; Li-Li Zhang

    2016-01-01

    Objective:To explore the clinical effect of triamcinolone acetonide ammonia bromine joint hydrochloric acid on patients with secretory otitis media and the influences on the body's inflammatory factors and cellular immunologic parameters.Methods:A total of 40 cases of single ear secretory otitis media patients of the same period in our hospital were randomly selected as experimental group, using triamcinolone acetonide ammonia bromine joint hydrochloric acid treatment; And 40 cases of single ear secretory otitis media patients of the same period were randomly selected as control group, using dexamethasone treatment. To observe the clinical efficacy of two groups of patients and detect the inflammatory factors and cellular immune index level of the two groups of patients before and after treatment.Results:The total effective rate(90%) of treatment group is significantly higher than that (80%) of control group (P0.05). After treatment, the serum and ear effusion inflammatory cytokines levels of the two groups were significantly lower than that before treatment (P0.05); The CD4+/CD8+ levels of experimental group were significantly higher than the control group (P0.05). Conclusions: The triamcinolone acetonide ammonia bromine joint hydrochloric acid treatment is more conducive to improve the immune function of the secretory otitis media patients and treatment effect, which has important clinical significance on the treatment of secretory otitis media patients.

  4. Kinetic study of the prehydrolysis of bagasse pith with hydrochloric acid in an agitated system

    Energy Technology Data Exchange (ETDEWEB)

    Villan Guerra, J.; Iglesias, R.G.; Lopez Planes, R.

    1981-01-01

    The hydrolysis of bagasse pith at 90-100 degrees with 0.25 N HCl gave sugar in 22% yield after 120 min. With 0.5 N HCl, the yield was 28% after 240 min. The specific constants of pentosan decomposition and of sugar formation were calculated, and the kinetic parameters (frequency factor, activation energy, and order of acid concentration) were determined. The pentosan decomposition constants were higher and the activation energies lower than literature values for hydrolysis with H/sub 2/SO/sub 4/.

  5. 硫铁矿烧渣双酸酸解工艺研究%Study on decomposition process of pyrite cinder with hydrochloric acid and sulfuric acid

    Institute of Scientific and Technical Information of China (English)

    左大学; 王仁宗

    2012-01-01

    The decomposition process of pyrite cinder with hydrochloric acid and sulfuric acid , and its influence factors are studied. Through orthogonal test, the optimum process conditions are confirmed including: the consumption factor of hydrochloric acid with w(HC1) of 37% is 0.12; the consumption factor of sulfuric acid with w(H2SO4) of 65%-70% is 0.95, the reaction temperature is of 125 ℃, the reaction time is of 4h. The decomposition rate of pyrite cinder can reach to above 95%, and the product ferric sulfate solution can be used to produce polymeric ferric sulfate and iron oxide pigments.%研究了硫铁矿烧渣双酸酸解工艺及影响酸解的因素。通过正交实验,找到最适宜的工艺条件:w(HCl)37%,盐酸用量系数为0.12,硫酸用量系数为0.95,硫酸W(H2SO4)为65%~70%,反应温度为125℃,反应时间为4h,酸解率可达95%以上,制得的硫酸铁盐溶液可用作生产聚合硫酸铁及氧化铁系颜料的原料。

  6. Seed Extract of Psidium guajava as Ecofriendly Corrosion Inhibitor for Carbon Steel in Hydrochloric Acid Medium

    Institute of Scientific and Technical Information of China (English)

    K.P.Vinod Kumar; M. Sankara Narayana Pillai; G. Rexin Thusnavis

    2011-01-01

    The anticorrosion characteristics of the seeds of Psidium guajava (P. Guajava) fruits on carbon steel in acid medium were examined with weight loss data and subsequently thermodynamic factors such as heat of adsorption of the inhibitor on the metal surface (Q), change in entropy (△S), change in free energy of the reaction (△G), corrosion rate (CR) and energy of activation for corrosion reaction of carbon steel (E) were also evaluated. Adsorption isotherm was plotted to study the adsorption of the inhibitor on the metal surface with increasing concentration of the inhibitor. The functional groups responsible for inhibition were investigated using Fourier transform infrared (FT-IR) spectra. Electrochemical parameters were evaluated through the potentiodynamic Tafel polarization and impedance spectral studies. Scanning electron microscopy (SEM) micrographs were recorded to investigate the change in surface morphology. The complete study reveals the efficiency of seed extract of P. Guajava as a safe, ecofriendly and alternate corrosion inhibitor for carbon steel in acid medium.

  7. Punica granatum leave extract as green corrosion inhibitor for mild steel in Hydrochloric acid

    Directory of Open Access Journals (Sweden)

    Abboud Y.

    2013-09-01

    Full Text Available Leave of Punica granatum extract (LPGE as green inhibitor for the corrosion of mild steel in 1M HCl solution was studied using weight-loss and potentiodynamic polarization measurements. The results obtained revealed that LPGE has fairly good inhibiting properties for mild steel corrosion in 1M HCl solution, with efficiency of around 94 % at a concentration of 1 g/l. The inhibition was of a mixed anodic–cathodic nature. The film which is formed over the metal surface was analysed by FT-IR spectroscopy. Further examination using X-ray diffraction confirms the role of LPGE as an effective corrosion inhibitor for mild steel in acid media.

  8. Thallium extraction from hydrochloric acid media into a deep eutectic solvent using bis(2-ethylhexyl) phosphate

    Science.gov (United States)

    Tran, Kate; Volia, Merinda; Tereshatov, Evgeny; Folden, Charles, III

    2016-09-01

    The chemical properties of superheavy elements are relatively unknown due to their short half-lives and difficulty of production. In preparation for a future experiment to study the chemical properties of element 113, separation techniques have been used to study the behavior of its homologs, In and Tl. Previous work studied the liquid-liquid extraction of radioactive 201Tl (t1 / 2 = 3 . 04 d) from various concentrations of HCl into a mixture of menthol and lauric acid that formed a so-called deep eutectic solvent (DES). This work focuses on the effects of adding an extraction agent, bis(2-ethylhexyl) phosphate (HDEHP), to the DES on the efficiency of thallium extraction. The extraction of Tl(I) was generally poor, both with and without HDEHP added. In contrast, 111In (t1 / 2 = 2 . 80 d) showed significant extraction using HDEHP added to the same DES. This difference in behavior could potentially be exploited in a future experiment on the chemistry of element 113. National Science Foundation.

  9. Formation of Hydrogen-Ion in Isomolar Solution of Hydrochloric and Hydrobromic Acids and Their Salts

    Directory of Open Access Journals (Sweden)

    M.A. Kovaleva

    2016-09-01

    Full Text Available Despite the presence of a large amount of factual material on thermodynamic parameters of complexation of agents in different solvents, including mixed ones, obtained knowledge is specific in nature. In order to identify more general patterns, studies are relevant that would allow to interpret the obtained data taking into account the interaction between chemical forms in solutions. This paper presents a general approach to studying weak ionic interactions in solutions that allows to simultaneously determine the constants of these interactions and the parameters characterizing the influence of changes in the ionic environment on these constants by the example of chlorides and bromides of alkali metals. The obtained constants for hydrosulfate-ion formation and the imperfection parameters can be a reference material for more accurate calculation of the concentration of hydrogen ions in sulfuric acid solutions. The developed approach and patterns identified in the work can be used to study the balanced states for formation of low and medium stable complexes.

  10. Effect of commercial fluoride dentifrices against hydrochloric acid in an erosion-abrasion model.

    Science.gov (United States)

    Passos, Vanara Florêncio; de Vasconcellos, Andréa Araújo; Pequeno, José Heriberto Pinheiro; Rodrigues, Lidiany Karla Azevedo; Santiago, Sérgio Lima

    2015-01-01

    This study assessed the effect of three commercial dentifrices with different fluoride-containing compounds in controlling the progression of dentin loss using an in vitro erosion-abrasion model. Dentin specimens were randomized into four groups (n = 10): control (no F), Elmex (1,400 ppm AmF), Meridol (1,400 ppm AmF/SnF2), and Crest Pro-Health (1,100 ppm SnF2). The dentin specimens were submitted to cycles of demineralization (HCl 0.01 M for 60 s), remineralization (artificial saliva for 60 min), and immersion in 1:3 w/w of dentifrice/artificial saliva, followed by toothbrushing (150 brushing strokes). The cycle was repeated three times daily for 5 days. Surface loss was quantified by stylus profilometry. Data were submitted to one-way ANOVA and Tukey's tests (p fluoride can strengthen dental tissue against erosive acid damage. However, the beneficial effect of different fluorides present in commercial dentifrices is questionable. Thus, a determination of an effective fluoride dentifrice may be beneficial in the reduction of the erosive process in patients with gastric disorders.

  11. 盐酸浸出赤泥回收铝的研究%Study on Aluminum Recovery from Red Mud with Hydrochloric Acid

    Institute of Scientific and Technical Information of China (English)

    王克勤; 王皓; 李生虎

    2012-01-01

    The hydrochloric acid leaching process of aluminum from Bayer red mud was studied. The effects of temperature, time, ratio of liquid to solid (L/S) and concentration of hydrochloric acid on aluminum leaching rate were investigated. The industrial experiment of aluminum recovery from red mud was conducted. The results show that factors affecting the rate of aluminum extraction in sequence are temperature, L/S, hydrochloric acid concentration and leaching time. The leaching rate and recovery rate of aluminum from red mud is 88. 13% and 80. 26% respectively after two-step leached at 80℃, evaporation, de-titanium, de-calcium, neutralization and dissolving with sodium hydroxide solution.%研究了盐酸浸出拜耳法赤泥中铝的过程.考察浸出温度、浸出时间、液固比和酸度对铝浸出率的影响,并进行了赤泥回收铝的工业化试验.结果表明,影响铝浸出率的主次因素依次是浸出温度、液固比、盐酸浓度和浸出时间.赤泥在80℃下进行两段浸出,再经蒸发、除钛、除钙、中和及氢氧化钠溶液溶出,铝浸出率为88.13%,回收率为80.26%.

  12. Inhibition Behaviour of Some Isonicotinic Acid Hydrazides on the Corrosion of Mild Steel in Hydrochloric Acid Solution

    Directory of Open Access Journals (Sweden)

    M. P. Chakravarthy

    2013-01-01

    Full Text Available New corrosion inhibitors, namely, isonicotinic acid (1H-indol-3-yl-methylenehydrazide (INIMH and isonicotinic acid (1H-pyrrol-2-yl-methylenehydrazide (INPMH, have been synthesized, and their inhibitive characteristics for the corrosion of mild steel in 0.5 M HCl were investigated by mass loss and electrochemical techniques. The structures of the synthesized compounds were confirmed using spectral studies. Potentiodynamic polarization studies revealed that the investigated inhibitors are of mixed type. Various thermodynamic parameters were evaluated. Langmuir adsorption isotherm was found to be the best description for both inhibitors. FTIR spectra, energy dispersive X-ray spectroscopy (EDX, and scanning electron microscopy (SEM were performed to characterize the passive film on the metal surface.

  13. A two-stage pretreatment process using dilute hydrochloric acid followed by Fenton oxidation to improve sugar recovery from corn stover.

    Science.gov (United States)

    Li, Wenzhi; Liu, Qiyu; Ma, Qiaozhi; Zhang, Tingwei; Ma, Longlong; Jameel, Hasan; Chang, Hou-Min

    2016-11-01

    A two-stage pretreatment process is proposed in this research in order to improve sugar recovery from corn stover. In the proposed process, corn stover is hydrolyzed by dilute hydrochloric acid to recover xylose, which is followed by a Fenton reagent oxidation to remove lignin. 0.7wt% dilute hydrochloric acid is applied in the first stage pretreatment at 120°C for 40min, resulting in 81.0% xylose removal. Fenton reagent oxidation (1g/L FeSO4·7H2O and 30g/L H2O2) is performed at room temperature (about 20°C) for 12 has a second stage which resulted in 32.9% lignin removal. The glucose yield in the subsequent enzymatic hydrolysis was 71.3% with a very low cellulase dosage (3FPU/g). This two-stage pretreatment is effective due to the hydrolysis of hemicelluloses in the first stage and the removal of lignin in the second stage, resulting in a very high sugar recovery with a low enzyme loading. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Studies on quality improvement in wheat gluten's physical and chemical properties by hydrochloric acid treatment%盐酸处理对谷朊粉理化性质改良的研究

    Institute of Scientific and Technical Information of China (English)

    张德欣

    2012-01-01

    利用盐酸处理改善谷朊粉的溶解度、乳化性、起泡性等理化性质,研究盐酸与谷朊粉的相对浓度、反应温度、反应时间、盐酸浓度对谷朊粉理化性质的影响.结果表明,盐酸处理改良谷朊粉理化性质的最佳条件:谷朊粉质量百分比为8%,盐酸:谷朊粉为3.5:100(质量比),反应温度65℃.试验证明,盐酸处理对谷朊粉的溶解度、乳化性及其稳定性、起泡性及其稳定性都有显著作用.%Using hydrochloric acid treatment improves the gluten's physical and chemical properties of solubility-, emulsiftcation, foaming ability ami etc. The effects of several physical and chemical properties were researched, of hydrochloric acid and gluten relative concentration, reaction temperature, reaction time, hydrochloric acid coticentratioa on gluten. Test results showed that the rn-odified gluten hydrochloric acid treatiment for the optimum conditions of the physical and chemical properties were;mass contest of gluten %%, Hydrochloric acid to gluten 3. 5 · 100 (mass), reaction temperature 65℃, The.experiments proved! that Hydrochloric acid treatment on the gluten's solubility, emulsification and its stability, foaming ability are significantly.

  15. Extraction of Sm(IIIand Nd(III with N,N,N’,N’-tetrabutyl-3-oxy-diglycolamidefrom hydrochloric acid

    Directory of Open Access Journals (Sweden)

    Yang J.H.

    2013-01-01

    Full Text Available The extraction behavior of Sm(III and Nd(III with N,N,N’,N’-tetrabutyl-3-oxa-diglycolamide (TBDGA in 70% kerosene-30% n-octanol from hydrochloride acid wasstudied. The effect of hydrochloric acid concentration, extractant concentration,and temperature on the distribution of rare earth elementswas investigated. The extraction mechanism was established and the stoichiometry of the main extracted species was confirm to be SmCl3•2TBDGA and NdCl3•2TBDGA for Sm(III and Nd(III, respectively. The extraction distribution ratio decreases with an increase in temperature, which demonstrates that the extraction reaction is exothermic. The IR spectra of the loaded organic phase and free extractant were recorded and discussed.

  16. Ethanol-based organosolv treatment with trace hydrochloric acid improves the enzymatic digestibility of Japanese cypress (Chamaecyparis obtusa) by exposing nanofibers on the surface.

    Science.gov (United States)

    Hideno, Akihiro; Kawashima, Ayato; Endo, Takashi; Honda, Katsuhisa; Morita, Masatoshi

    2013-03-01

    The effects of adding trace acids in ethanol based organosolv treatment were investigated to increase the enzymatic digestibility of Japanese cypress. A high glucose yield (60%) in the enzymatic hydrolysis was obtained by treating the sample at 170 °C for 45 min in 50% ethanol liquor containing 0.4% hydrochloric acid. Moreover, the enzymatic digestibility of the treated sample was improved to ∼70% by changing the enzyme from acremonium cellulase to Accellerase1500. Field emission scanning electron microscopy revealed the presence of lignin droplets and partial cellulose nanofibers on the surface of the treated sample. Simultaneous saccharification and fermentation of the treated samples using thermotolerant yeast (Kluyveromyces marxianus NBRC1777) was tested. A high ethanol concentration (22.1 g/L) was achieved using the EtOH50/W50/HCl0.4-treated sample compared with samples from other treatments.

  17. Pharmacokinetics and tissue residues of hydrochloric acid albendazole sulfoxide and its metabolites in crucian carp (Carassius auratus) after oral administration.

    Science.gov (United States)

    Li, Zaijian; Chen, Cuilan; Ai, Diyun; Wang, Chunmei; Li, Jing; Qi, Yuanhua; Yi, Weixue; Shen, Hongchun; Cao, Jiyue

    2012-03-01

    The pharmacokinetics and residues elimination of hydrochloric acid albendazole sulfoxide (ABZSO) and its metabolites were studied in healthy crucian carp (Carassius auratus, 250 ± 30 g) kept at water temperatures of 10 °C and 25 °C. The concentrations of ABZSO and its metabolites concentration in plasma and tissues were determined using high-performance liquid chromatography (HPLC) using an ultraviolet detector. The results revealed that the plasma concentration of ABZSO in plasma was significantly higher than that of albendazole sulfone (ABZSO(2)), whereas albendazole-2-aminosulfone (ABZ-SO(2)NH(2)) was not detected. The plasma concentrations of ABZSO and its main metabolite ABZSO(2) concentration-time data were fitted using a single-compartment model at 10 °C and 25 °C. The absorption half-life (t₁/₂ka) of ABZSO was 3.86 h at 10 °C and 1.29 h at 25 °C, whereas the elimination half-life (t₁/₂ke) was 16.34 h at 10 °C and 6.72 h at 25 °C; the maximum plasma concentration (C(max)) and the time-point of maximum plasma concentration (T(p)) were calculated as 3.20 μg mL(-1) and 10.58 h at 10 °C, 4.39 μg mL(-1) and 3.80 h at 25 °C. The distribution volume (V(d)/F) of ABZSO was estimated to be 1.99 L kg(-1) at 10 °C and 1.53 L kg(-1) at 25 °C; the total body clearance (CL(b)) of ABZSO were computed as 0.08 and 0.19 L/(h kg) at 10 and 25 °C, respectively; the areas under the concentration-time curve (AUC) was 118.22 μg mL(-1)h at 10 °C and 63.12 μg mL(-1)h at 25 °C. The [Formula: see text] of ABZSO(2) was found to be 6.39 °C at 10 °C and 3.73 h at 25 °C, whereas the [Formula: see text] was 12.86 h at 10 °C and 6.56 h at 25 °C; the C(max) and T(p) of ABZSO(2) was calculated as 0.78 μg mL(-1) and 12.82 h at 10 °C, 1.03 μg mL(-1) and 7.04 h at 25 °C, respectively; the V(d)/F of ABZSO(2) were estimated to be 6.43 L kg(-1) at 10 °C and 4.61 Lkg(-1) at 25 °C; the CL(b) of ABZSO(2) were computed as 0.34 and 0.49 L/(h kg) at 10 °C and 25

  18. Electrochemical measurements for the corrosion inhibition of mild steel in 1 M hydrochloric acid by using an aromatic hydrazide derivative

    Directory of Open Access Journals (Sweden)

    P. Preethi Kumari

    2017-07-01

    Full Text Available The influence of an aromatic hydrazide derivative, 2-(3,4,5-trimethoxybenzylidene hydrazinecarbothioamide (TMBHC as corrosion inhibitor on mild steel in 1 M hydrochloric acid was studied by Tafel polarization and electrochemical impedance spectroscopy (EIS technique. The results showed that the inhibition efficiency (% IE of TMBHC increased with increasing inhibitor concentrations and also with increase in temperatures. TMBHC acted as a mixed type of inhibitor and its adsorption on mild steel surface was found to follow Langmuir’s adsorption isotherm. The evaluation of thermodynamic and activation parameters indicated that the adsorption of TMBHC takes place through chemisorption. The formation of protective film was further confirmed by scanning electron microscopy (SEM.

  19. Study on the inhibition of mild steel corrosion by 1,3-bis-(morpholin-4-yl-phenyl-methyl-thiourea in hydrochloric acid medium

    Directory of Open Access Journals (Sweden)

    Devaraj Karthik

    2014-12-01

    Full Text Available 1,3-Bis-(morpholin-4-yl-phenyl-methyl-thiourea (MBT was synthesized and their influence on the inhibition of corrosion on mild steel in various hydrochloric acid concentrations has been investigated by weight loss, potentiodynamic polarization, electrochemical impedance (EI, Tafel polarization, scanning electron microscope (SEM and FT-IR methods. The result of weight loss study shows that the corrosion inhibition efficiency (IE is directly proportional to the concentration of the inhibitor and inversely proportional to the temperature. Electrochemical study proved that the inhibitor acts as a mixed type inhibitor. SEM shows the formation of a protective film of the inhibitor on the mild steel. The IR data also provide evidence for the anticorrosion effect of the inhibitor.

  20. Experimental and theoretical study for corrosion inhibition of mild steel in normal hydrochloric acid solution by some new macrocyclic polyether compounds

    Energy Technology Data Exchange (ETDEWEB)

    Lebrini, M. [Unite de Catalyse et de Chimie du Solide, CNRS UMR 8181, ENSCL, BP 90108, F-59652 Villeneuve d' Ascq Cedex (France); Lagrenee, M. [Unite de Catalyse et de Chimie du Solide, CNRS UMR 8181, ENSCL, BP 90108, F-59652 Villeneuve d' Ascq Cedex (France); Vezin, H. [Laboratoire de Chimie Organique et Macromoleculaire, CNRS UMR 8009, USTL Bat C4, F-59655 Villeneuve d' Ascq Cedex (France); Traisnel, M. [Laboratoire des Procedes d' Elaboration des Revetements Fonctionnels, PERF UMR 8008, ENSCL, BP 90108, F-59652 Villeneuve d' Ascq Cedex (France); Bentiss, F. [Laboratoire de Chimie de Coordination et d' Analytique, Faculte des Sciences, Universite Chouaib Doukkali, BP 20, M-24000 El Jadida (Morocco)]. E-mail: f.bentiss@pop.ensc-lille.fr

    2007-05-15

    New macrocyclic polyether compounds containing a 1,3,4-thiadiazole moiety have been prepared to study the corrosion inhibitive effect of mild steel in normal hydrochloric acid solutions. The salient features obtained from weight loss and electrochemical impedance spectroscopy (EIS) have been discussed. The results of these investigations have shown enhancement in inhibition efficiencies with the extent of the polyethylene glycol unit that forms a cavity. Data obtained from EIS show a frequency distribution and therefore a modelling element with frequency dispersion behaviour, a constant phase element (CPE) has been used. Display Omitted Adsorption of n-MCTH was found to follow the Langmuir's adsorption isotherm. The thermodynamic functions of adsorption process were calculated from experimental ac impedance data and the interpretation of the results are given. Molecular modelling has been conducted in an attempt to correlate the corrosion inhibition properties with the calculated quantum chemical parameters.

  1. Thermodynamic characterization of metal dissolution and inhibitor adsorption processes in mild steel/2,5-bis(n-thienyl)-1,3,4-thiadiazoles/hydrochloric acid system

    Energy Technology Data Exchange (ETDEWEB)

    Bentiss, F. [Laboratoire de Cristallochimie et Physicochimie du Solide, CNRS UMR 8012 ENSCL, BP 90108, F-59652 Villeneuve d' Ascq Cedex (France); Laboratoire de Chimie de Coordination et d' Analytique, Universite Chouaib Doukkali, Faculte des Sciences, B.P. 20, El Jadida (Morocco); Lebrini, M. [Laboratoire de Cristallochimie et Physicochimie du Solide, CNRS UMR 8012 ENSCL, BP 90108, F-59652 Villeneuve d' Ascq Cedex (France); Lagrenee, M. [Laboratoire de Cristallochimie et Physicochimie du Solide, CNRS UMR 8012 ENSCL, BP 90108, F-59652 Villeneuve d' Ascq Cedex (France)]. E-mail: michel.lagrenee@ensc-lille.fr

    2005-12-15

    The corrosion inhibition of mild steel in 1 M hydrochloric acid solution by some 2,5-bis(n-thienyl)-1,3,4-thiadiazoles (n-TTH) has been studied in relation to the concentration of the inhibitors as well as the temperature using chemical (weight loss) and electrochemical (ac impedance and dc polarisation) techniques. All the methods employed are in reasonable agreement. The protection efficiency increases with increasing inhibitors concentration and with increasing temperature. The thermodynamic functions of dissolution and adsorption processes were calculated from experimental polarisation data and the interpretation of the results are given. Adsorption of n-TTH was found to follow the Langmuir's adsorption isotherm and the ability of the molecule to chemisorb on the steel surface was dependent on the position of the sulphur atom on the thienyl substituent.

  2. Effect of optimized structure and electronic properties of some benzimidazole derivatives on corrosion inhibition of mild steel in hydrochloric acid medium: Electrochemical and theoretical studies

    Indian Academy of Sciences (India)

    Alokdut Dutta; Sujit Sankar Panja; M M Nandi; Dipankar Sukul

    2015-05-01

    The corrosion inhibitive action of a few benzimidazole derivatives namely 2-(benzamido) ethylbenzimidazole (BAEBI), 2-(-benzenesulphonamido) ethylbenzimidazole (BSAEBI), 2-(benzamido) methylbenzimidazole (BAMBI) and 2-(-benzenesulphonamido) methylbenzimidazole (BSAMBI), towards mild steel in hydrochloric acid has been studied using potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) methods. The results show that these compounds get adsorbed on the mild steel surface following Temkin adsorption isotherm, and act as mixed-type inhibitors. The inhibition efficiencies are found to follow the order, BAEBI > BSAEBI > BAMBI > BSAMBI. This observation is explained in terms of chain length, relative effects of amido and sulphonamido groups, possible structural factors, spatial orientations, energy gap between the frontier molecular orbitals, different intrinsic molecular parameters, like, global hardness and softness, and number of electrons transferred.

  3. Extraction of Gold(III) from Hydrochloric Acid Solutions with a PVC-based Polymer Inclusion Membrane (PIM) Containing Cyphos(®) IL 104.

    Science.gov (United States)

    Bonggotgetsakul, Ya Ya Nutchapurida; Cattrall, Robert W; Kolev, Spas D

    2015-12-08

    Poly(vinyl chloride) (PVC) based polymer inclusion membranes (PIMs), with different concentrations of Cyphos® IL 104 as the membrane extractant/carrier, were studied for their ability to extract Au(III) from hydrochloric acid solutions. Some of the PIMs also contained one of the following plasticizers or modifiers: 2-nitrophenyloctyl ether, dioctylphthalate, 1-dodecanol, 1-tetradecanol, or tri(2-ethylhexyl) phosphate. The best performance, in terms of extraction rate and amount of Au(III) extracted, was exhibited by a PIM consisting of 25 wt% Cyphos(®) IL 104, 5 wt% 1-dodecanol, and 70 wt% PVC. An almost complete back-extraction of the Au(III) extracted from this membrane was achieved by using a 0.10 mol L(-1) Na₂SO₃ receiver solution at pH 8. The stoichiometry of the extracted Au(III)/Cyphos® IL 104 adduct was determined as [P]⁺ [AuCl₄](-) H⁺ [PO₂](-) where [P]⁺ and [PO₂](-) represent trihexyl(tetradecyl) phosphonium and bis(2,4,4-trimethylpentyl) phosphinate ions, respectively. Back-extraction of Au(III) is suggested to occur by reduction of Au(III) to Au(I), with the formation of the species [Au(SO₃)₂](3-) in the aqueous receiver solution. Loss of 1-dodecanol from the newly developed PIM to the aqueous solutions in contact with it was observed, which indicated that this membrane was suitable for single use in the efficient recovery of Au(III) from hydrochloric acid solutions of electronic scrap or recycled jewelry.

  4. Inhibition Performance of Furfural on Carbon Steel in Hydrochloric Acid%糠醛对碳钢在盐酸中的缓蚀性能研究

    Institute of Scientific and Technical Information of China (English)

    杨昌炎; 杨光宏; 刘东; 丁一刚; 吴元欣; 戢峻; 李姝

    2011-01-01

    As a corrosion inhibitor, the corrosion inhibition of furfural obtained from straws by microwave pyrolysis was investigated in hydrochloric acid solution. The weight loss and electrochemistry polarization evaluation, and the absorbance of furfural on carbon steel was preliminary discussed. The results showed that furfural, as a complex inhibitor, gives nice inhibition efficiency on carbon steel in hydrochloric acid medium. The inhibition efficiency of furfural was up to 91. 3 % when the mass fraction of furfural reaches 0.7 % at room temperature. It can also reduce the activation energy of corrosion reaction. This results in a decrease of corrosion rate. The inhibition performance of furfural is affected by temperature, and its absorbance behaviors can be expressed by the equation of Langmuir model.%以秸秆催化热解制得的糠醛作为盐酸酸洗缓蚀剂,其缓蚀效率采用失重法和电化学极化法进行了评价,初步探讨其吸附性能.结果表明:糠醛属于混合型缓蚀剂,在盐酸介质中缓蚀作用良好,室温下糠醛添加量为0.7%时,其缓蚀效率可达91.3%,能使碳钢的腐蚀反应活化能降低,腐蚀速率明显下降,同时其缓蚀效率受温度的影响较大,其吸附符合Langmuir吸附规律.

  5. 植物细胞有丝分裂实验中盐酸浓度对实验效果影响的研究%Effective research on different concentrations of hydrochloric acid in plant cell mitosis experiment

    Institute of Scientific and Technical Information of China (English)

    归改霞

    2015-01-01

    目的:探讨有丝分裂实验中盐酸浓度对实验效果的影响。方法:通过使用不同浓度的盐酸做为解离液进行实验,从中选取最适合的盐酸浓度,从而达到最理想的实验效果。结果:通过实验比较,解离液中盐酸的浓度为25%比较合适。结论:植物细胞有丝分裂实验,在选材、培养、取材均为最优条件下,解离液中盐酸的浓度是实验成功的关键。当盐酸的浓度为25%时,实验成功率最高,能达到最佳效果。%Objective: To investigate effects of different concentrations of hydrochloric acid in plant cell mitosis experiment. Methods: In order to achieve the best experimental results, the most suitable concentration of hydrochloric acid was selected in experiments. Results: Based on experimental comparison, concentration of hydrochloric acid of 25% in dissociation solution is suitable. Conclusion: When other conditions are the best, concentration of hydrochloric acid is the key in plant cell mitosis experiment. When concentration of hydrochloric acid was 25%, there was highest efficiency and the best result.

  6. Electrochemical Study on Corrosion Inhibition of Copper in Hydrochloric Acid Medium and the Rotating Ring-Disc Voltammetry for Studying the Dissolution

    Directory of Open Access Journals (Sweden)

    A. K. Satpati

    2011-01-01

    Full Text Available Dissolution characteristics of copper in hydrochloric acid medium and the effect of 4-amino 1,2,4-triazole (ATA on the corrosion process have been studied using conventional electrochemical techniques and rotating ring-disc electrodes (RRDEs. Corrosion potential (corr and corrosion current density (corr were obtained by Tafel extrapolation methods. Charge transfer resistance (ct and double-layer capacitance (dl were obtained from the electrochemical impedance spectroscopy (EIS. ATA was shown to be an effective inhibitor for the copper-corrosion inhibition in acid medium. The corrosion rate was retarded in presence of inhibitors mainly because of the adsorption of the inhibitor on the electrode surface. Adsorption of the inhibitor on the metal surface was found to follow the Langmuir adsorption isotherm. Standard free energy change of the adsorption process (Δ0ad was calculated to be −54.3 kJ mol−1; such a large negative value of Δ0ad suggests the prescence of a chemisorption process.

  7. Inhibition performance of thiourea on carbon steel in hydrochloric acid%氢氟酸中硫脲对碳钢缓蚀性能的研究

    Institute of Scientific and Technical Information of China (English)

    韩成利

    2013-01-01

    The adsorption and corrosion inhibition of thiourea on carbon steel in hydrochloric acid has been investigated by weight-loss method.The experimental data have been treated with adsorption theory and sekine method.The result showed that thiourea has efficiently inhibited the corrosion of iron in hydrofluoric acid solution, the adsorption rule of thiourea on the surface of iron obeyed Langmuir isotherm.%采用失质量法研究了硫脲在氢氟酸中对碳钢的吸附及缓蚀作用,并应用吸附理论Sekine方法对实验数据进行处理。结果表明,硫脲对氢氟酸体系中碳钢的腐蚀有良好的抑制作用,硫脲在碳钢片表面产生了吸附,且低浓度下吸附基本符合Langmuir等温式。

  8. Corrosion inhibition of 6061 Al-15 vol. pct. SiC(p) composite and its base alloy in a mixture of sulphuric acid and hydrochloric acid by 4-(N,N-dimethyl amino) benzaldehyde thiosemicarbazone

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, Geetha Mable [Department of Chemistry, National Institute of Technology Karnataka, Surathkal, Srinivasnagar 575 025, Mangalore, Karnataka (India); Nayak, Jagannath [Department of Metallurgical and Materials Engineering, National Institute of Technology Karnataka, Surathkal, Srinivasnagar 575 025, Karnataka (India); Shetty, A. Nityananda, E-mail: nityashreya@gmail.com [Department of Chemistry, National Institute of Technology Karnataka, Surathkal, Srinivasnagar 575 025, Mangalore, Karnataka (India)

    2011-02-15

    Research highlights: {yields} Corrosion inhibition of Al-SiC composite. {yields} DMABT as corrosion inhibitor. {yields} Inhibition through physisorption of DMABT. - Abstract: The corrosion inhibition characteristics of 4-(N,N-dimethylamino) benzaldehyde thiosemicarbazone (DMABT) on the corrosion behavior of 6061 Al-15 vol. pct. SiC(p) composite and its base alloy were studied at different temperatures in acid mixture medium containing varying concentrations of hydrochloric acid and sulphuric acid using Tafel extrapolation technique and ac impedance spectroscopy (EIS). The effect of inhibitor concentration, temperature and concentration of the acid mixture media on the inhibitor action was investigated. It was found that inhibition efficiencies increase with the increase in inhibitor concentration, but decrease with the increase in temperature and with the increase in concentration of the acid media. Thermodynamic parameters for dissolution process were determined. The adsorption of DMABT on both the composite and base alloy was found to be through physisorption obeying Freundlich adsorption isotherm.

  9. Hydrothermal synthesis of highly crystalline RuS{sub 2} nanoparticles as cathodic catalysts in the methanol fuel cell and hydrochloric acid electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yanjuan [Key Laboratory of Marine Chemistry Theory and Technology, Minisry of Education Ocean University of China, Qingdao, 266100 (China); College of Material Science and Engineering, Key Laboratory of Automobile Materials of Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Li, Nan, E-mail: lin@jlu.edu.cn [College of Material Science and Engineering, Key Laboratory of Automobile Materials of Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Yanagisawa, Kazumichi [Research Laboratory of Hydrothermal Chemistry, Kochi University, Kochi 780-8520 (Japan); Li, Xiaotian [College of Material Science and Engineering, Key Laboratory of Automobile Materials of Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Yan, Xiao [Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012 (China)

    2015-05-15

    Highlights: • Highly crystalline RuS{sub 2} nanoparticles have been first synthesized by a “one-step” hydrothermal method. • The product presents a pure cubic phase of stoichiometric ratio RuS{sub 2} with average particle size of 14.8 nm. • RuS{sub 2} nanoparticles were used as cathodic catalysts in methanol fuel cell and hydrochloric acid electrolysis. • The catalyst outperforms commercial Pt/C in methanol tolerance and stability towards Cl{sup −}. - Abstract: Highly crystalline ruthenium sulfide (RuS{sub 2}) nanoparticles have been first synthesized by a “one-step” hydrothermal method at 400 °C, using ruthenium chloride and thiourea as reactants. The products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy/energy disperse spectroscopy (SEM/EDS), thermo gravimetric-differential thermal analyze (TG-DTA), transmission electron microscopy equipped with selected area electron diffraction (TEM/SAED). Fourier transform infrared spectra (IR), and X-ray photoelectron spectroscopy (XPS). XRD result illustrates that the highly crystalline product presents a pure cubic phase of stoichiometric ratio RuS{sub 2} and the average particle size is 14.8 nm. SEM and TEM images display the products have irregular shape of 6–25 nm. XPS analyst indicates that the sulfur exists in the form of S{sub 2}{sup 2−}. Cyclic voltammetry (CV), rotating disk electrode (RDE), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) measurements are conducted to evaluate the electrocatalytic activity and stability of the highly crystalline RuS{sub 2} nanoparticles in oxygen reduction reaction (ORR) for methanol fuel cell and hydrochloric acid electrolysis. The results illustrate that RuS{sub 2} is active towards oxygen reduction reaction. Although the activity of RuS{sub 2} is lower than that of Pt/C, the RuS{sub 2} catalyst outperforms commercial Pt/C in methanol tolerance and stability towards Cl{sup −}.

  10. 盐酸改性粉煤灰净化低温低浊水的试验研究%The Experimental Research on Purifying Low Temperature and Low Turbidity Water by Hydrochloric Acid Modified Fly Ash

    Institute of Scientific and Technical Information of China (English)

    刘书贤; 魏晓刚; 王伟; 杜平; 肖利萍

    2012-01-01

    由于粉煤灰具有良好的吸附性能且富含硅、铝和铁等元素,将其作为助凝剂,用盐酸对粉煤灰改性后与聚合硫酸铁PFS联合使用处理低温低浊水.在用盐酸对粉煤灰进行改性时,研究了振荡时间、振荡速度、盐酸浓度等试验因素对改性粉煤灰吸附助凝效果的影响,得出盐酸改性粉煤灰的最佳试验条件为:振荡器振荡速度80 r/min,100 mL 3.6 mol/L盐酸与5g预处理粉煤灰混合振荡3h,试验温度25℃.改性后粉煤灰的比表面积明显增加,并且粉煤灰中部分硅、铝和铁等元素溶出,转变成具有很好絮凝作用的Al3+、Fe3+和H2SiO3,粘附于粉煤灰表面,在处理低温低浊水的过程中能较好地发挥吸附助凝效果.%Becaouse of the excellent adsorption performance and high containing of silicon, aluminum and iron and other elements, fly ash by hydrochloric acid modified was used as a coagulant to purify low temperature and low turbidity water with reagent PFS. When the fly ash were modified by hydrochloric acid, the experimental factors just as duration of oscillation, speed of oscillation and hydrochloric acid concentration were researched. The best experimental conditions of hydrochloric acid modification were follows: the speed of oscillation 80r/min, 100 mL 3.6 mol/L of hydrochloric acid and 5 g the coal fly ash mixed in the oscillator for about 3 h, the experiment temperature 25 ℃. The specific surface of modified fly ash increased significantly, the elements such as silicon, aluminum and iron dissolved from fly ash and they turned into Al3+, Fe3+ and H2SiO3 (adhesion on the surface of fly ash) whose flocculation were strong. In the process of purifying low temperature and low turbidity water by hydrochloric acid modified fly ash, the adsorptive property can be exerted effectively.

  11. Role of temperature and hydrochloric acid on the formation of chlorinated hydrocarbons and polycyclic aromatic hydrocarbons during combustion of paraffin powder, polymers, and newspaper.

    Science.gov (United States)

    Takasuga, Takumi; Umetsu, Norihito; Makino, Tetsuya; Tsubota, Katsuya; Sajwan, Kenneth S; Kumar, Kurunthachalam Senthil

    2007-07-01

    Formation of chlorinated hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) were determined using a laboratory-scale incinerator when combusting materials at different temperatures, different concentrations of hydrochloric acid (HCl), and when combusting various types of polymers/newspaper. Polychlorobenzenes (PCBz), polychlorophenols (PCPhs), polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and their toxic equivalency (TEQ) and PAHs were highlighted and reported. Our results imply maximum formation of chlorinated hydrocarbons at 400 degrees C in the following order; PCBz>or=PCPhs>PCDFs>PCDDs>TEQ on a parts-per-billion level. Similarly, a maximum concentration of chlorinated hydrocarbons was noticed with an HCl concentration at 1000 ppm with the presence of paraffin powder in the following order; PAHs>PCBz>or=PCPhs>PCDFs>PCDDs>TEQ an a parts-per-billion level. PAHs were not measured at different temperatures. Elevated PAHs were noticed with different HCl concentrations and paraffin powder combustion (range: 27-32 microg/g). While, different polymers and newspaper combusted, nylon and acrylonitrile butadiene styrene (ABS) produced the maximum hydrogen cyanide (HCN) concentration, concentrations of PCDD/FS, dioxin-like polychlorinated biphenyls (DL-PCBs), and TEQ were in a decreasing order: polyvinylchloride (PVC)newspapernewspapernewspaper newspapernewspaper

  12. Improve the Properties of p-i-n α-Si:H Thin-Film Solar Cells Using the Diluted Hydrochloric Acid-Etched GZO Thin Films

    Directory of Open Access Journals (Sweden)

    Fang-Hsing Wang

    2013-01-01

    Full Text Available Gallium-doped zinc oxide (GZO thin films were deposited on glass, and the process parameters are RF power of 50 W and working pressure of 5 mTorr, and the substrate temperature was changed from room temperature to 300°C. At first, the thickness was around 300 nm by controlling the deposition time. The effects of substrate temperature on the crystallinity, lattice constant (c, carrier mobility, carrier concentration, resistivity, and optical transmission rate of the GZO thin films were studied. The 200°C-deposited GZO thin films had the best crystallinity, the larger carrier concentration and carrier mobility, and the lowest resistivity. For that, the thickness of the GZO thin films was extended to around 1000 nm. Hydrochloric (HCl acid solutions with different concentrations (0.1%, 0.2%, and 0.5% were used to etch the surfaces of the GZO thin films, which were then used as the substrate electrodes to fabricate the p-i-n α-Si:H thin-film solar cells. The haze ratio of the GZO thin films increased with increasing HCl concentration, and that would effectively enhance light trapping inside the absorber material of solar cells and then improve the efficiency of the fabricated thin-film solar cells.

  13. 盐酸浓度对酸解玉米淀粉结晶结构和性能的影响%Effects of hydrochloric acid concentration on crystalline structure and properties of corn starch

    Institute of Scientific and Technical Information of China (English)

    左迎峰; 张彦华; 杨龙; 谭海彦; 顾继友

    2013-01-01

    以玉米淀粉为原料,用盐酸对其酸解制备酸解玉米淀粉.考虑盐酸浓度对酸解玉米淀粉结构和性能的影响.通过抽滤洗涤法、X射线衍射(XRD)、旋转粘度计、差示扫描量热法(DSC)和热重分析(TGA)对酸解淀粉的回收率、结晶度、糊化粘度、糊化温度和热性能进行分析.结果表明,酸解玉米淀粉的回收率、结晶度和糊化温度随盐酸浓度的增大,先增大后减小,盐酸浓度为0.5 mol/L时,回收率、结晶度和糊化温度都达到最大值;糊化粘度随盐酸浓度的增大而迅速减小;酸解改性对玉米淀粉的热稳定性影响较小.%Acid hydrolysis corn starch was prepared by hydrochloric acid method to study the effects of hydrochloric acid concentrations on the structure and properties of acid hydrolysis com starch.. The crystallinity, gelatinization viscosity, gelatinization temperature and thermal performance of acid hydrolysis starch were analyzed by using filtration washing method, X-ray diffraction, rotational viscometer, differential scanning calorimetry and thermo gravimetric analysis, respectively. The results show that the recovery yield, crystallinity and gelatinization temperature increased first and then decreased with the increase of hydrochloric acid concentration, and reached the maximum values when hydrochloric acid concentration was 0.5 mol/L; the gelatinization viscosity rapidly decreased with increase of hydrochloric acid concentration. So the acid modification had small effect on thermal stability of corn starch.

  14. 没食子酸在含盐酸高温液态水中的稳定性%Stability of Gallic Acid in High Temperature Water with Hydrochloric Acid

    Institute of Scientific and Technical Information of China (English)

    张迎杰; 傅杰; 刘林; 吕秀阳

    2013-01-01

    The stability of gallic acid in high temperature water with hydrochloric acid was studied in a high-pressure batch reactor.The effects of initial concentration of gallic acid,concentration of hydrochloric acid and reaction temperature on the stability of gallic acid were investigated.The results indicated that HC1 concentration was an important factor to the stability of gallic acid,in which the stability of gallic acid decreased as the concentration of HC1 increased.Reaction temperature influenced the stability of gallic acid significantly.As the temperature increased,the conversion of gallic acid increased rapidly,whereas the stability of gallic acid decreased remarkably.Below 413.15 K,gallic acid was relatively stable in HC1 solutions.The kinetic data of the study obtained at different hydrochloric acid concentrations and reaction temperatures were fitted with a pesudo-first-order kinetic equation.The apparent activation energy for the decarboxylation of gallic acid at different hydrochloric acid concentration was obtained by Arrhenius equation.All the obtained apparent activation energy values were close to 112 kJ/mol and not sensitive to the HCl concentration.%采用间歇高压反应釜研究了没食子酸在含盐酸高温液态水中的稳定性.在数据重现性研究基础上,考察了没食子酸初始浓度、盐酸浓度和反应温度等对没食子酸稳定性的影响.结果表明:盐酸浓度对没食子酸的稳定性有较显著的影响,且随着盐酸浓度的增加,稳定性下降:温度对没食子酸稳定性影响十分显著,随着温度的升高,没食子酸转化速率快速增加,稳定性显著降低,但在413.15 K以下没食子酸在盐酸溶液中有较好的稳定性.采用拟一级反应动力学方程,拟合得到了不同盐酸浓度和反应温度下的反应速率常数,进而利用Arrhenius方程得到了不同盐酸浓度没食子酸脱羧反应的表观活化能,表明在盐酸存在下,没食子酸脱羧反

  15. Synthesis and characterization of a novel eco-friendly corrosion inhibition for mild steel in 1 M hydrochloric acid.

    Science.gov (United States)

    Al-Amiery, Ahmed A; Binti Kassim, Fatin A; Kadhum, Abdul Amir H; Mohamad, Abu Bakar

    2016-01-22

    The acid corrosion inhibition process of mild steel in 1 M HCl by azelaic acid dihydrazide has been investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, open circuit potential (OCP) and electrochemical frequency modulation (EFM). Azelaic acid dihydrazide was synthesized, and its chemical structure was elucidated and confirmed using spectroscopic techniques (infrared, nuclear magnetic resonance and mass spectroscopy). Potentiodynamic polarization studies indicate that azelaic acid dihydrazide is a mixed-type inhibitor. The inhibition efficiency increases with increased inhibitor concentration and reaches its maximum of 93% at 5 × 10(-3) M. The adsorption of the inhibitor on a mild steel surface obeys Langmuir's adsorption isotherm. The effect of te perature on corrosion behavior in the presence of 5 × 10(-3) M inhibitor was studied in the temperature range of 30-60 °C. The results indicated that inhibition efficiencies were enhanced with an increase in concentration of inhibitor and decreased with a rise in temperature. To inspect the surface morphology of inhibitor film on the mild steel surface, scanning electron microscopy (SEM) was used before and after immersion in 1.0 M HCl.

  16. Operational aspect of hot water style 2-in-1 graphite hydrochloric acid furnace%热水型二合一石墨盐酸炉的运行情况

    Institute of Scientific and Technical Information of China (English)

    吕旭琦; 冯海平

    2012-01-01

    通过改造传统工艺盐酸炉为热水型二合一石墨盐酸炉,回收盐酸生产中产生的热量制热水。采用热水型溴化锂制冷机组制7℃水供生产用。工艺改造后,达到了节能减排预期目标。%The tradition graphite hydrochloric acid furnace was transformed into hot water style 2-in-1 graphite hydrochloric acid furnace.The hot water was used to produce 7℃ water.After process transformation,the ammonia refrigerating machine was stoped and the power consumption reduced,the energy conservation goals were achieved.

  17. Kinetic Approach to the Mechanism of Redox Reaction of Pyrocatechol Violet and Nitrite Ion in Aqueous Hydrochloric Acid

    Directory of Open Access Journals (Sweden)

    A. Adetoro

    2011-10-01

    Full Text Available The kinetics of the oxidation of Pyrocatechol violet (PCVH by nitrite ion (NO2- in aqueous acidic medium has been studied at 24±1ºC, I = 0.50 mol/dm3(NaCl, [H+] = 1.0×10-3 mol/dm3. The reaction is first order to [PCVH] and half order to [NO2-]. The redox reaction displayed a 1:1 stoichiometry and obeys the rate law: d[PCVH]/dt = (a + b[H+] [PCVH][NO2-]½. The second-order rate constant increases with increase in acid concentration and ionic strength. This system displayed positive salt effect while spectroscopic investigation and Michaelis-Menten plot showed evidence of intermediate complex formation in the course of the reaction. A plausible mechanism has been proposed for the reaction.

  18. 盐酸法提取污泥中蛋白质过程的研究%Study on the Processes of Protein Extraction from Sludge by Hydrochloric Acid

    Institute of Scientific and Technical Information of China (English)

    秦晓; 刘勇

    2012-01-01

    为了探索剩余污泥中蛋白质的提取方法,采用盐酸和氢氧化钠对污泥中蛋白质进行了提取,并对提取液进行了紫外光谱分析.结果证明盐酸提取法更有利于污泥中蛋白质的提取操作,并可以保证蛋白质质量.随后,实验考察了温度、污泥浓度、盐酸浓度以及操作时间对提取液中蛋白质浓度的影响情况.结果表明:蛋白质浓缩随温度呈先慢后快的增加趋势,随污泥浓度呈线性增加趋势,随盐酸浓度呈先快后慢增加趋势,适当延长时间有利于提升提取液中的蛋白质浓度.%In order to explore the methods of protein extraction from sludge, firstly, hydrochloric acid and sodium hydroxide were used to extract protein in this paper, and then the extracts were analyzed by UV spectrum. The results showed that hydrochloric acid extraction method was more conducive to the protein extraction and could ensure the protein quality. Subsequently, the effects of temperature, sludge concentration, hydrochloric acid concentration and operating time on protein concentration in the extract were experimentally investigated in detail. The results show that: the change trend of the protein concentration in the extract with temperature is slow after fast, with sludge concentration is linear, with hydrochloric acid is fast before slow, and appropriate extension of time will help to enhance the protein concentration in the extract.

  19. 盐酸戊乙奎醚治疗有机磷农药中毒临床分析%Clinical Analysis of Hydrochloric Acid Penehyclidine in Treatmentof Organophosphorus Pesticide Poisoning

    Institute of Scientific and Technical Information of China (English)

    曹振强; 汪显琪

    2012-01-01

    Objective: To investigate the efficacy and clinical significance of hydrochloric acid penehyclidine in the treatment of organophosphorus pesticide poisoning. Method: Chosing 126 cases of organophosphorus pesticide poisoning patients. Then explored the comprehensive methods of hydrochloric acid penehyclidine treatment. Result: After 3 to 5 days of comprehensive hydrochloric acid penehyclidine treatment, 122 patients escaped from danger successfully and 4 patients died. Another 15 patients responded with dry mouth , flushing face and so on, and then was cured slowly after stopping the treatment. Conclusion: Hydrochloric acid penehyclidine is characteristic of long-lasting time, simple operation and so on. It is of better clinical utility and safety, and can obviously speed up the level of consciousness, reduce treatment time and improve the treatment success rate for organophosphorus pesticide poisoning patients.%目的:探讨盐酸戊乙奎醚治疗有机磷农药中毒病症的疗效及临床意义.方法:选取我院急诊科126例有机磷农药中毒患者,探讨盐酸戊乙奎醚治疗的综合方法,并结合实际分析其效果.结果:经盐酸戊乙奎醚综合治疗3-5d后,122例患者成功脱险,死亡4例.有15例出现口干、面红等不良反应,停药后自行缓解.结论:盐酸戊乙奎醚具有持续时间长、操作简便等特点,具有更好的临床实用性和安全性,对于有机磷农药中毒患者能明显加快清醒程度,缩短时间,提高救治成功率.

  20. Formation of super-concentrated hydrochloric acid in the third phase in tertiary amine N235-PtCl62--HCl system and its influences on the Pt microemulsion extraction

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper,we have investigated the formation of the third-phase in tertiary amine(N235)-PtCl62--HCl system and the microscopic phase structural evolution of platinum-loaded organic phases before and after the occurrence of the third-phase.The third-phase is characterized by various spectroscopic techniques,and the small angle X-ray scattering(SAXS) experiments demonstrate the appearance of nano-aggregates,i.e.,water-in-oil reversed micelles,in the third phase.The experimental results indicate that(1) formation of the third phase is related to the aggregation behaviors of nano-reversed micelles in which a super-concentrated hydrochloric acid formed with the H+ to H2O molar ratio being much higher than that of the conventional 37 wt% saturated hydrochloric acid.(2) The occurrence of the super-concentrated HCl results in a great amount of H+ and Cl-ions enriched and confined within the nano-water pools of W/O reversed micelles in third phase.Therefore,the coordination behaviors of platinum complex ions in that super-concentrated hydrochloric acid are very different from their corresponding behaviors in bulk aqueous solutions.It is possible that H+ ions participate in the formation of such complexes as HmPtCl6z+ in the super-concentrated hydrochloric acid.(3) The relative contents of various HmPtCl6z+ complexes are different corresponding to the H+ ion concentrations in confined nanowater pools.The association ability of the acidified tertiary amine N235 molecules(R3NH+) with various HmPtCl6z+ complexes plays an important role in affecting the platinum extraction behaviors.

  1. Chemical Polymerization Kinetics of Poly-O-Phenylenediamine and Characterization of the Obtained Polymer in Aqueous Hydrochloric Acid Solution Using K2Cr2O7 as Oxidizing Agent

    Directory of Open Access Journals (Sweden)

    S. M. Sayyah

    2014-01-01

    Full Text Available The oxidative chemical polymerization of o-phenylenediamine (OPDA was studied in hydrochloric acid solution using potassium dichromate as oxidant at 5°C. The effects of potassium dichromate, hydrochloric acid, and monomer concentrations on the polymerization reaction were investigated. The order of reaction with respect to potassium dichromate, hydrochloric acid, and monomer concentration was found to be 1.011, 0.954, and 1.045, respectively. Also, the effect of temperature on the polymerization rate was studied and the apparent activation energy of the polymerization reaction was found to be 63.658 kJ/mol. The obtained polymer was characterized using XPS, IR, UV-visible, and elemental analysis. The surface morphology of the obtained polymers was characterized by X-ray diffraction and transmission electron microscopy (TEM. The TGA analysis was used to confirm the proposed structure and number of water molecules in each polymeric chain unit. The ac conductivity (σac of (POPDA was investigated as a function of frequency and temperature. The ac conductivity was interpreted as a power law of frequency. The frequency exponent (s was found to be less than unity and decreased with the increase of temperature, which confirms that the correlated barrier hopping model was the dominant charge transport mechanism.

  2. Treasure of the Past VI: Standard Potential of the Silver-Silver-Chloride Electrode from 0° to 95° C and the Thermodynamic Properties of Dilute Hydrochloric Acid Solutions.

    Science.gov (United States)

    Bates, R G; Bower, V E

    2001-01-01

    From electromotive-force measurements of the cell without liquid junction: [Formula: see text]through the range 0° to 95° C, calculations have been made of (1) the standard potential of the silver-silver-chloride electrode, (2) the activity coefficient of hydrochloric acid in aqueous solutions from m (molality) =0 to m=0.1 and from 0° to 90° C, (3) the relative partial molal heat content of hydrochloric acid, and (4) the relative partial molal heat capacity of hydrochloric acid. The extrapolations were made by the method of least squares with the aid of punch-card techniques. Data from at least 24 cells were analyzed at each temperature, and 81 cells were studied at 25° C. The value of the standard potential was found to be 0.22234 absolute volt at 25° C, and the standard deviation was 0.02 millivolt at 0° C, 0.01 millivolt at 25° C, and 0.09 millivolt at 95° C. The results from 0° to 60° C are compared with earlier determinations of the standard potential and other quantities derived from the electromotive force.

  3. A novel triazole-based cationic gemini surfactant: synthesis and effect on corrosion inhibition of carbon steel in hydrochloric acid

    Energy Technology Data Exchange (ETDEWEB)

    Qiu Lingguang [School of Chemistry and Chemical Engineering, Anhui University, Hefei 230039 (China)]. E-mail: lgahu@163.com; Xie Anjian [School of Chemistry and Chemical Engineering, Anhui University, Hefei 230039 (China); Shen Yuhua [School of Chemistry and Chemical Engineering, Anhui University, Hefei 230039 (China)

    2005-06-15

    A triazole-based cationic gemini surfactant, 3,5-bis(methylene octadecyl dimethylammonium chloride)-1,2,4-triazole (18-triazole-18) has been synthesized, and its effect on corrosion inhibition of A{sub 3} steel in 1 M HCl has been studied using the weight-loss method. The result showed that 18-triazole-18 acted as an excellent inhibitor in 1 M HCl. It was found that the adsorption mechanism of 18-triazole-18 on the steel surface in acid medium was quite different from that of cationic gemini surfactants containing dimethylene as a spacer, as well as that of conventional cationic single-chained surfactants, which is due to unique molecular structure of 18-triazole-18. 18-Triazole-18 may be adsorbed on the steel surface in acid medium through a maximum of four atoms or groups, i.e., the two nitrogen atoms of triazole ring and two quaternary ammonium head groups. Four regions of surfactant concentration could be divided to illustrate the adsorption of 18-triazole-18 on the steel surface, and four different adsorption mechanisms may take place in different regions of surfactant concentration.

  4. Trapping of hydrochloric and hydrofluoric acid at vacancies on and underneath the ice I(h) basal-plane surface.

    Science.gov (United States)

    Pinheiro Moreira, Pedro Augusto Franco; de Koning, Maurice

    2013-10-31

    We investigate the uptake of HCl and HF at lattice vacancies in ice Ih as a function of their distance to the basal-plane surface layer using density-functional theory calculations. The results for HCl display large dispersions in the binding-energy results due to the appearance of distinct dissociation states. The layer-averaged results suggest that the uptake of HCl is most favorable in the two layers just below the surface, which is consistent with available experimental indications. The behavior of HF is found to be manifestly different due to the fact that it is a weaker acid. The dispersion in the binding-energy values is significantly less compared to the case of HCl, and the average values are essentially equal to the bulk value, regardless of layer position. This suggests that, in contrast to the case of HCl, there should not be any tendency for accumulation of HF near the surface.

  5. Corrosion inhibition efficiency and surface activity of benzothiazol-3-ium cationic Schiff base derivatives in hydrochloric acid

    Energy Technology Data Exchange (ETDEWEB)

    Negm, N.A., E-mail: nabelnegm@hotmail.co [Petrochemicals Department, Egyptian Petroleum Research Institute, Nasr City, Cairo (Egypt); Elkholy, Y.M.; Zahran, M.K. [Chemistry Department, Faculty of Science, Helwan University, Helwan (Egypt); Tawfik, S.M. [Petrochemicals Department, Egyptian Petroleum Research Institute, Nasr City, Cairo (Egypt)

    2010-10-15

    Research highlights: {yields} Benzothiazolium inhibitors show high corrosion inhibition for carbon steel. {yields} Weight loss and corrosion rates decrease by increasing inhibitor dose. {yields} Inhibition mechanism suggested as physisorption mechanism supported by adsorption free energy values. {yields} The adsorption of the inhibitors obeys Langmuir isotherm. {yields} Side chains have ascending order on the corrosion inhibition of the different inhibitors. - Abstract: Two series of cationic Schiff base surfactants namely: 2-(benzylideneamino)-3-(2-oxo-2-alkoxyethyl)-1,3-benzothiazol-3-ium bromide and 2-[(4-methoxybenzylidene)amino]-3-(2-oxo-2-alkoxyethyl)-1, 3-benzothiazol-3-ium bromide were prepared and confirmed using elemental analysis, FTIR, and {sup 1}H NMR spectra. The surface activity of the synthesized Schiff bases showed their tendency towards adsorption at the interfaces. The prepared compounds were evaluated as corrosion inhibitors for carbon steel in 0.5 M HCl solution using gravimetric and polarization measurements. By fitting the gravimetric data, some thermodynamic and kinetic parameters were estimated. The adsorption of the inhibitors on the carbon steel surface obeyed Langmuir adsorption isotherm and had a physical mechanism. Polarization measurements showed that the synthesized inhibitors act as mixed inhibitors for carbon steel in the acidic media. The results of the corrosion inhibition using two different methods showed narrow differences in the obtained values between the two methods within 5%.

  6. Preparation of Butyl Chloride from Butanol and Hydrochloric Acid Using Ionic Liquids as Catalyst%离子液体催化丁醇与盐酸反应制备丁基氯

    Institute of Scientific and Technical Information of China (English)

    孙爱军; 聂毅; 李春喜; 王子镐

    2008-01-01

    The catalytic performance of some quaternary ammonium salts for the liquid phase reaction of butanol and hydrochloric acid at different conditions was studied experimentally and compared with the traditional catalyst (ZnC12). The organic ammonium catalysts investigated include ionic liquids N-butyl-N-methyl imidazolium fluobo-rate ([BMIM][BF4]) and N-butyl-N-methylimidazolium chloride ([BMIM]Cl) as well as hydrochloric salts of N-methylimidazol ([HMIM]Cl), pyridine ([Hpy]Cl) and triethylamine ([HEt3N]Cl). It is shown that the intrinsic catalytic performance of all organic ammonium salts except [Het3N]Cl is slightly superior to ZnCl2, while the se-lectivity of butyl chloride is nearly at the same level around 96%. The conversion of butanol increases slightly with temperature and the catalyst amount added while the variation of selectivity is not obvious. Based on the recycle experiments, the ionic liquids as catalyst for the reaction of butanol and hydrochloric acid can be used more than 5 times, which suggests great potential of using ionic liquids as novel catalyst for such reactions.

  7. [Suicidal poisoning due to hydrogen sulfide produced by mixing a liquid bath essence containing sulfur and a toilet bowl cleaner containing hydrochloric acid].

    Science.gov (United States)

    Kobayashi, Kanya; Fukushima, Hirofumi

    2008-04-01

    A 21-year-old man was found dead in a car. There were 9 empty bottles of 610HAP (a 440 g bottle of a liquid bath essence containing 160-195 g/kg sulfur) and 10 of Sunpole (a 500 mL bottle of a toilet bowl cleaner containing 9.5% HCl) in the car. The car doors were sealed with tape, and there was a strong smell of sulfur in and around the car. GC/MS analysis showed 0.66 microg/mL sulfide and 0.14 micromol/mL thiosulfate in the blood sample. The concentration of thiosulfate in the urine sample was normal. Police investigation concluded that the man killed himself by aspirating hydrogen sulfide that had been produced by mixing 610 HAP and Sunpole. To examine the amount of hydrogen sulfide produced, small portions of these liquids were mixed in a 560-mL volume flask. The results showed that 0.1 mL of each liquid produced 4,950 ppm of hydrogen sulfide, and 0.2 mL of each produced 10,800 ppm. According to these results, if the cabin volume is assumed to be 3,300 L, mixing 120 mL of each liquid produces a lethal level of hydrogen sulfide, i.e., 1,000 ppm. This was a rare suicide case, and it revealed the hazards of mixing of liquid bath essences containing sulfur and toilet bowl cleaners containing hydrochloric acid.

  8. 萃取净化盐酸法制备磷酸工艺研究%Study of Preparation Phosphoric Acid Process by Extraction and Purification of Hydrochloric Acid Process

    Institute of Scientific and Technical Information of China (English)

    杨站平; 闫小玲; 张树帜; 王长锐

    2014-01-01

    Based on preparation crude phosphoric acid by acid hydrolysis of ground phosphate rocks with hydrochloric acid , using process of combination of tributyl phosphate and kerosene mixed solvent extraction with chemical precipitation process to carry out purification treatment for crude phosphoric acid , after refine , concentration , removal of impurities and decolorization , food grade phosphoric product is obtained . Research results show that mass fraction of prepared product phosphoric acid is 85.2%, all indicators achieved not only meet standard requirements of industrial grade phosphoric acid , but also reach qualifications of food grade phosphoric acid .%以盐酸酸解磷矿粉制得粗磷酸为基础,采用磷酸三丁酯和煤油混合溶剂萃取与化学沉淀法相结合的工艺对粗磷酸进行净化处理,通过精制、浓缩、除杂、脱色后可制得食品级磷酸产品。研究结果表明:试验制得的产品磷酸质量分数为85.2%,各项指标不仅达到了工业级磷酸标准要求,而且达到了食品级磷酸标准要求。

  9. Microstructures of Al7.5Cr22.5Fe35Mn20Ni15 High-Entropy Alloy and Its Polarization Behaviors in Sulfuric Acid, Nitric Acid and Hydrochloric Acid Solutions

    Directory of Open Access Journals (Sweden)

    Chun-Huei Tsau

    2016-08-01

    Full Text Available This paper investigates the microstructures and the polarization behaviors of Al7.5Cr22.5Fe35Mn20Ni15 high-entropy alloy in 1M (1 mol/L deaerated sulfuric acid (H2SO4, nitric acid (HNO3, and hydrochloric acid (HCl solutions at temperatures of 30–60 °C. The three phases of the Al7.5Cr22.5Fe35Mn20Ni15 high-entropy alloy are body-centered cubic (BCC dendrites, face-centered cubic (FCC interdendrites, and ordered BCC precipitates uniformly dispersed in the BCC dendrites. The different phases were corroded in different acidic solutions. The passivation regions of the Al7.5Cr22.5Fe35Mn20Ni15 alloy are divided into three and two sub-regions in the solutions of H2SO4 and HNO3 at 30–60 °C, respectively. The passivation region of the Al7.5Cr22.5Fe35Mn20Ni15 alloy is also divided into two sub-domains in 1M deaerated HCl solution at 30 °C. The Al7.5Cr22.5Fe35Mn20Ni15 alloy has almost equal corrosion resistance in comparison with 304 stainless steel (304SS in both the 1M H2SO4 and 1M HCl solutions. The polarization behaviors indicated that the Al7.5Cr22.5Fe35Mn20Ni15 alloy possessed much better corrosion resistance than 304SS in 1M HNO3 solution. However, in 1M NaCl solution, the corrosion resistance of the Al7.5Cr22.5Fe35Mn20Ni15 alloy was less than 304SS.

  10. Sequential soil washing techniques using hydrochloric acid and sodium hydroxide for remediating arsenic-contaminated soils in abandoned iron-ore mines.

    Science.gov (United States)

    Jang, Min; Hwang, Jung Sung; Choi, Sang Il

    2007-01-01

    Sequential washing techniques using single or dual agents [sodium hydroxide (NaOH) and hydrochloric acid (HCl) solutions] were applied to arsenic-contaminated soils in an abandoned iron-ore mine area. We investigated the best remediation strategies to maximize arsenic removal efficiency for both soils and arsenic-containing washing solution through conducting a series of batch experiments. Based on the results of a sequential extraction procedure, most arsenic prevails in Fe-As precipitates or coprecipitates, and iron exists mostly in the crystalline forms of iron oxide. Soil washing by use of a single agent was not effective in remediating arsenic-contaminated soils because arsenic extractions determined by the Korean standard test (KST) methods for washed soils were not lower than 6mg kg(-1) in all experimental conditions. The results of X-ray diffraction (XRD) indicated that iron-ore fines produced mobile colloids through coagulation and flocculation in water contacting the soils, containing dissolved arsenic and fine particles of ferric arsenate-coprecipitated silicate. The first washing step using 0.2M HCl was mostly effective in increasing the cationic hydrolysis of amorphous ferrihydrite, inducing high removal of arsenic. Thus, the removal step of arsenic-containing flocs can lower arsenic extractions (KST methods) of washed soils. Among several washing trials, alternative sequential washing using 0.2M HCl followed by 1M HCl (second step) and 1M NaOH solution (third step) showed reliable and lower values of arsenic extractions (KST methods) of washed soils. This washing method can satisfy the arsenic regulation of washed soil for reuse or safe disposal application. The kinetic data of washing tests revealed that dissolved arsenic was easily readsorbed into remaining soils at a low pH. This result might have occurred due to dominant species of positively charged crystalline iron oxides characterized through the sequential extraction procedure. However

  11. Effects of chopping, and soaking in water, hydrochloric acidic and calcium hydroxide solutions on the nutritional value of Acacia villosa for goats

    Energy Technology Data Exchange (ETDEWEB)

    Wina, E. [Research Institute for Animal Production, Bogor (Indonesia)]. E-mail: winabudi@yahoo.com; Tangendjaja, B.; Susana, I.W.R. [Research Institute for Animal Production, Bogor (Indonesia)

    2005-08-19

    Acacia villosa, a thornless shrub legume, has potential as a feed supplement for ruminants if anti-nutritional factors, especially tannins, can be overcome. The effects of chopping and soaking the leaves on the amounts of tannin in the extracting solution and that left in the recovered leaves were studied. The tannin and non-tannin phenolics were solubilized in the extracting solution and the amount was increased with the soaking time. Soaking in calcium hydroxide solution, hydrochloric acid or water removed 41-76% of tannin and total phenolics removed from the recovered leaves. Soaking of the leaves also removed fermentable materials and reduced the gas production. In the first of two digestibility experiments, three groups of goats received one of these diets, those were: (1) sugar cane tops: unsoaked Acacia leaves (7:3), (2) sugar cane tops: water soaked Acacia leaves (7:3) and (3) sugar cane tops: water soaked Acacia leaves (7:3) + 100 g/day of cassava flour. Live weight of goats was measured every 2 weeks and a large increase in average daily gain was obtained for goats fed diet containing water soaked leaves and cassava flour (71 g/day) compared to those fed diet containing unsoaked leaves and water soaked leaves (38.9 and 44.7 g/day, respectively) (P < 0.05). In the second digestibility experiment, the three diets were: (1) sugar cane tops: unsoaked Acacia (7:3), (2) sugar cane tops water soaked Acacia (7:3), (3) sugar cane tops: calcium hydroxide soaked Acacia (7:3). A supplement of 100 g/day of cassava flour was added to each of these three diets. In both digestibility experiments, soaking improved intake and digestibility of Acacia leaves, and cassava flour increased the intake, but when all the diets contained cassava flour, there was no significant difference (P > 0.05) found in intake or digestibility between unsoaked and soaked leaves. In conclusion, soaking reduced tannin in Acacia leaves, improved digestibility and intake of Acacia leaves. In the

  12. Effect of a low-viscosity adhesive resin on the adhesion of metal brackets to enamel etched with hydrochloric or phosphoric acid combined with conventional adhesives.

    Science.gov (United States)

    Yetkiner, Enver; Ozcan, Mutlu; Wegehaupt, Florian Just; Wiegand, Annette; Eden, Ece; Attin, Thomas

    2013-12-01

    This study investigated the effect of a low-viscosity adhesive resin (Icon) applied after either hydrochloric (HCl) or phosphoric acid (H3PO4) on the adhesion of metal brackets to enamel. Failure types were analyzed. The crowns of bovine incisors (N = 20) were sectioned mesio-distally and inciso-gingivally, then randomly assigned to 4 groups according to the following protocols to receive mandibular incisor brackets: 1) H3PO4 (37%)+TransbondXT (3M UNITEK); 2) H3PO4 (37%)+Icon+TransbondXT; 3) HCl (15%)+Icon (DMG)+TransbondXT 4) HCl (15%)+Icon+Heliobond (Ivoclar Vivadent)+TransbondXT. Specimens were stored in distilled water at 37°C for 24 h and thermocycled (5000x, 5°C to 55°C). The shear bond strength (SBS) test was performed using a universal testing machine (1 mm/min). Failure types were classified according to the Adhesive Remnant Index (ARI). Contact angles of adhesive resins were measured (n = 5 per adhesive) on ceramic surfaces. No significant difference in SBS was observed, implying no difference between combinations of adhesive resins and etching agents (p = 0.712; ANOVA). The Weibull distribution presented significantly lower Weibull modulus (m) of group 3 (m = 2.97) compared to other groups (m = 5.2 to 6.6) (p group 1 (45.4 ± 7.9) > group 2 (44.2 ± 10.6) > group 3 (42.6 ± 15.5). While in groups 1, 3, and 4 exclusively an ARI score of 0 (no adhesive left on tooth) was observed, in group 2, only one specimen demonstrated score 1 (less than half of adhesive left on tooth). Contact angle measurements were as follows: Icon (25.86 ± 3.81 degrees), Heliobond (31.98 ± 3.17 degrees), TransbondXT (35 ± 2.21 degrees). Icon can be safely used with the conventional adhesives tested on surfaces etched with either HCl or H3PO4.

  13. Estudios Cinéticos de la Disolución de Hidroboracita en Soluciones de Acido Clorhídrico y Acido Sulfúrico Dissolution Kinetics of Hydroboracite in Hydrochloric Acid and Sulphuric Acid Solutions

    Directory of Open Access Journals (Sweden)

    Graciela V Morales

    2008-01-01

    Full Text Available Se realizan estudios cinéticos de la disolución de hidroboracita en soluciones de ácido clorhídrico y ácido sulfúrico en un reactor tanque agitado discontinuo de acero inoxidable, a presión atmosférica. Se investiga el efecto de la temperatura, el tamaño de partícula, la relación sólido/líquido y la concentración de ácido sobre la velocidad de disolución. Los resultados experimentales permiten observar que la velocidad de disolución aumenta con el incremento de la concentración del ácido y de la temperatura, y disminuye con el aumento del tamaño de partícula y con la relación sólido/líquido. La energía de activación aparente calculada para la disolución de hidroboracita en soluciones de ácido clorhídrico es 44.9 kJ/mol, lo cual no permite inferir cual es la etapa controlante del proceso; mientras que la energía de activación aparente calculada para la disolución de hidroboracita en soluciones de ácido sulfúrico es 14.6 kJ/mol, lo cual permite inferir que el proceso ocurre con control difusivo.The dissolution kinetics of hydroboracite in hydrochloric acid and sulphuric acid solutions was investigated. The experiments were carried out in a steel batch reactor equipped with a mechanical stirrer, at atmospheric pressure. The effect of reaction temperature, particle size, solid/liquid ratio and acid concentration on the dissolution rate was determined. It was found that the dissolution rate increased with increasing the acid concentration and reaction temperature. However, the increase of particle size and solid/liquid ratio decreased the dissolution rate. The activation energy for the hydroboracite dissolution in hydrochloric acid was calculated as 44.9 kJ/mol, which does not permit to know the process controlling step. The activation energy for the hydroboracite dissolution in sulphuric acid was found to be 14.6 kJ/mol, which indicates that the dissolution is a diffusion controlled process.

  14. Limonene as Green Inhibitor for Steel Corrosion in Hydrochloric Acid Solutions%盐酸溶液中钢铁腐蚀的绿色缓蚀剂柠檬油精

    Institute of Scientific and Technical Information of China (English)

    CHAIEB E.; BOUYANZER A.; HAMMOUTI B.; BERRABAH M.

    2009-01-01

    The inhibition of steel corrosion in hydrochloric acid solutions by limonene, which was extracted from citrus and orange fruit, was studied using measurements of mass loss, electrochemical polarisation and electrochemical impedance spectroscopy (EIS) methods. Naturally, the substance reduced the rate of corrosion. The linearity of the cathodic curves for all concentrations indicated that the law of Tafel was followed. The effectiveness of inhibition increased with the increase in concentration of limonene and this exceeded 72% at 0.220 g. L-1. The inhibition efficiency is temperature independent in the temperature range of 298-328 K. Adsorption of the substance on the surface of steel obeys the Frumkin isotherm model.

  15. Investigation of adsorption and inhibitive effect of acid red GRE (183 dye on the corrosion of carbon steel in hydrochloric acid media

    Directory of Open Access Journals (Sweden)

    M. Abd El-raouf

    2015-09-01

    Full Text Available The adsorption and corrosion inhibitive effect of acid red GRE (183 dye on carbon steel alloy in 1 M HCl solutions was studied using various techniques. Results of weight loss, Tafel polarization measurements and electrochemical impedance spectroscopy (EIS techniques show that this compound has fairly good inhibiting properties for steel corrosion in acidic bath; with efficiency around 96% at a concentration of 50 ppm. The inhibition is of a mixed anodic–cathodic nature. Factors affecting the corrosion process have been calculated and discussed. Acid red GRE (183 dye was shown to be an inhibitor in the acidic corrosion. Inhibition efficiency increased with acid red GRE (183 dye concentration but decreased with rise in temperature, corrosion inhibition is attributed to the adsorption of acid red GRE (183 dye on the carbon steel surface via a physical adsorption mechanism. Langmuir isotherm is found to provide an accurate description of the adsorption behavior of the investigated azo compound. The nature of the protective film was investigated using SEM and EDX techniques.

  16. Influence of several nonferrous metals in the treatment of residual liquors from hydrochloric acid pickling processes. Influencia de diversos metales no ferreos en el tratamiento de lejias residuales de decapado con acido clorhidrico

    Energy Technology Data Exchange (ETDEWEB)

    Negro, C.; Cobos, M.A.; Latorre, R.; Dufour, J.; Formoso, A.; Lopez, F.

    1994-01-01

    In the oxiprecipitation of waste liquors from siderurgical processes of pickling with hydrochloric acid, several kinds of iron oxides and oxihydroxides are obtained: alpha-FeOOH, gamma-FeOOH, Fe[sub 3]O[sub 4], gamma-Fe[sub 2]O[sub 3]. Fe[sub 2]O[sub 3].1,2H[sub 2]O, etc. These products can be used like pigments in the painting industry and like raw materials for the obtaining of ferrites. Varying the operation conditions, the presence of these products can be changed greatly, obtaining different mixtures of them. The presence of non-ferrous metals catalyzes and modifies the mechanism of the reaction, yielding pure products. This simplifies their later industrial applications. The aim of this work is to determine the influence of Cu(II), Zn(II), Mo(VI) and Al(III) on the oxiprecipitation of residual liquors from hydrochloric acid pickling processes, selecting the most favourable operation conditions at which it is possible to obtain products for industrial applications.

  17. Cell cycle profiling by image and flow cytometry: The optimised protocol for the detection of replicational activity using 5-Bromo-2′-deoxyuridine, low concentration of hydrochloric acid and exonuclease III

    Science.gov (United States)

    Konečný, Petr; Frydrych, Ivo; Koberna, Karel

    2017-01-01

    The approach for the detection of replicational activity in cells using 5-bromo-2′-deoxyuridine, a low concentration of hydrochloric acid and exonuclease III is presented in the study. The described method was optimised with the aim to provide a fast and robust tool for the detection of DNA synthesis with minimal impact on the cellular structures using image and flow cytometry. The approach is based on the introduction of breaks into the DNA by the low concentration of hydrochloric acid followed by the subsequent enzymatic extension of these breaks using exonuclease III. Our data showed that the method has only a minimal effect on the tested protein localisations and is applicable both for formaldehyde- and ethanol-fixed cells. The approach partially also preserves the fluorescence of the fluorescent proteins in the HeLa cells expressing Fluorescent Ubiquitin Cell Cycle Indicator. In the case of the short labelling pulses that disabled the use of 5-ethynyl-2′-deoxyuridine because of the low specific signal, the described method provided a bright signal enabling reliable recognition of replicating cells. The optimized protocol was also successfully tested for the detection of trifluridine, the nucleoside used as an antiviral drug and in combination with tipiracil also for the treatment of some types of cancer. PMID:28426799

  18. Cell cycle profiling by image and flow cytometry: The optimised protocol for the detection of replicational activity using 5-Bromo-2'-deoxyuridine, low concentration of hydrochloric acid and exonuclease III.

    Science.gov (United States)

    Ligasová, Anna; Konečný, Petr; Frydrych, Ivo; Koberna, Karel

    2017-01-01

    The approach for the detection of replicational activity in cells using 5-bromo-2'-deoxyuridine, a low concentration of hydrochloric acid and exonuclease III is presented in the study. The described method was optimised with the aim to provide a fast and robust tool for the detection of DNA synthesis with minimal impact on the cellular structures using image and flow cytometry. The approach is based on the introduction of breaks into the DNA by the low concentration of hydrochloric acid followed by the subsequent enzymatic extension of these breaks using exonuclease III. Our data showed that the method has only a minimal effect on the tested protein localisations and is applicable both for formaldehyde- and ethanol-fixed cells. The approach partially also preserves the fluorescence of the fluorescent proteins in the HeLa cells expressing Fluorescent Ubiquitin Cell Cycle Indicator. In the case of the short labelling pulses that disabled the use of 5-ethynyl-2'-deoxyuridine because of the low specific signal, the described method provided a bright signal enabling reliable recognition of replicating cells. The optimized protocol was also successfully tested for the detection of trifluridine, the nucleoside used as an antiviral drug and in combination with tipiracil also for the treatment of some types of cancer.

  19. Study of Temperature Effect on the Corrosion Inhibition of C38 Carbon Steel Using Amino-tris(Methylenephosphonic Acid in Hydrochloric Acid Solution

    Directory of Open Access Journals (Sweden)

    Najoua Labjar

    2011-01-01

    Full Text Available Tafel polarization method was used to assess the corrosion inhibitive and adsorption behaviours of amino-tris(methylenephosphonic acid (ATMP for C38 carbon steel in 1 M HCl solution in the temperature range from 30 to 60∘C. It was shown that the corrosion inhibition efficiency was found to increase with increase in ATMP concentration but decreased with temperature, which is suggestive of physical adsorption mechanism. The adsorption of the ATMP onto the C38 steel surface was found to follow Langmuir adsorption isotherm model. The corrosion inhibition mechanism was further corroborated by the values of kinetic and thermodynamic parameters obtained from the experimental data.

  20. Alteration of the phospho- or neutral lipid content and fatty acid composition in Listeria monocytogenes due to acid adaptation mechanisms for hydrochloric, acetic and lactic acids at pH 5.5 or benzoic acid at neutral pH.

    Science.gov (United States)

    Mastronicolis, Sofia K; Berberi, Anita; Diakogiannis, Ioannis; Petrova, Evanthia; Kiaki, Irene; Baltzi, Triantafillia; Xenikakis, Polydoros

    2010-10-01

    This study provides a first approach to observe the effects on Listeria monocytogenes of cellular exposure to acid stress at low or neutral pH, notably how phospho- or neutral lipids are involved in this mechanism, besides the fatty acid profile alteration. A thorough investigation of the composition of polar and neutral lipids from L. monocytogenes grown at pH 5.5 in presence of hydrochloric, acetic and lactic acids, or at neutral pH 7.3 in presence of benzoic acid, is described relative to cells grown in acid-free medium. The results showed that only low pH values enhance the antimicrobial activity of an acid. We suggest that, irrespective of pH, the acid adaptation response will lead to a similar alteration in fatty acid composition [decreasing the ratio of branched chain/saturated straight fatty acids of total lipids], mainly originating from the neutral lipid class of adapted cultures. Acid adaptation in L. monocytogenes was correlated with a decrease in total lipid phosphorus and, with the exception of cells adapted to benzoic acid, this change in the amount of phosphorus reflected a higher content of the neutral lipid class. Upon acetic or benzoic acid stress the lipid phosphorus proportion was analysed in the main phospholipids present: cardiolipin, phosphatidylglycerol, phosphoaminolipid and phosphatidylinositol. Interestingly only benzoic acid had a dramatic effect on the relative quantities of these four phospholipids.

  1. Comparative study on solubilities of bismuth, bismuth oxide,and bismuth sulfide in hydrochloric acid-thiourea%铋、氧化铋、硫化铋在盐酸-硫脲中溶解性的比较研究

    Institute of Scientific and Technical Information of China (English)

    马哈亚·艾斯江; 巴哈尔古丽·别克吐尔逊

    2012-01-01

    在盐酸介质中及55℃加热条件下,铋与硫脲形成黄色络合物,从而建立了用分光光度法比较铋、氧化铋、硫化铋在盐酸-硫脲中溶解性的新方法.研究了反应介质、试剂浓度、加热时间、加热温度、震荡速率等因素的影响.在最佳实验条件下,溶液的质量浓度为0.04~0.24 mg/mL时符合比尔定律.相关系数R=0.999 9,检出限为1.05×10-2 μg/mL,标准偏差SD=0.003 5,相对标准偏差RSD=2.42%,摩尔吸收系数为1.515×105 L/(mol·cm),加标回收率为96.7%~98.8%.实验结果表明,铋、氧化铋、硫化铋的溶解性顺序大小为:铋>氧化铋>硫化铋.%A yellow complex is formed from bismuth and thiourea in hydrochloric acid under the heated condition of 55 °C. Thus a new method is set up to compare the solubilities of bismuth, bismuth oxide, and bismuth sulfide in hydrochloric acid-thiourea by using spectrophotometry.Effects of factors, such as reaction medium, reagent concentration, heating time, heating temperature, and oscillation speed,were studied respectively .Under the optimum experimental conditions, mass concentration of the solution is in line with Beer's law, when it is within the range of 0.04-0.24 mg/mL.The correlation coefficient (R) is 0.999 9.The detection limit is 1.05xl0-2μg/mL.The standard deviation is 0.003 5.The relative standard deviation (RSD) is 2.42%.The molar absorption coefficient is 1.515xl05 L/(mol-cm).The recovery rate of standard addition is at 96.7%~98.8%. Experimental result showed that the solubilities of bismuth,bismuth oxide,and bismuth sulfide in hydrochloric acid-thiourea is in order by size as following: Bi>Bi2O3>Bi2S3.

  2. Characteristics of the Carbon Nanotube Coated with Polyaniline Doped with Hydrochloric Acid and Dodecylbenzene Sulfonic Acid%盐酸与DBSA共掺杂聚苯胺修饰碳纳米管性能的研究

    Institute of Scientific and Technical Information of China (English)

    张爱波; 刘刚; 薛艳丽; 郑亚萍; 赵纯颖

    2011-01-01

    The MWNTs/polyaniline composites were prepared via in-situ emulsion polymerization using hydrochloric acid and dodecylbenzene sulfonic acid as dopants. The FTIR spectra, TEM and TGA were used to characterize the morphology and performance of the composites. The TEM results show that the surface of MWNTs are coated by polyaniline composites and the thickness of the coating layer is 10~20nm. The solubility is increased in DMF, THF and chloroform. The thermal stability of the composite is highly improved at 520~750℃ and the encapsulation rate is 15.16%. The conductivity of the sample is increased from 10-7S/cm to 10-3S/cm.%采用原位乳液聚合法制备了盐酸与十二烷基苯磺酸(DBSA)共掺杂聚苯胺/MWNTs复合材料.利用FTIR、TEM和TG等对复合材料的形貌和性能进行了表征.TEM结果表明苯胺共聚物包覆于碳纳米管表面,包覆厚度为10~20nm.复合材料在DMF、THF和氯仿中的溶解性大幅度提高,在520~750℃的热稳定性明显提高,包覆率为15.16%,电导率从聚苯胺的10-7A/cm增大到10-3S/cm.

  3. 氯化法回收废钯-氧化铝催化剂中的钯%Recovery of Palladium from Spent Pd-Al2O3 Catalyst by Hydrochloric Acid Leaching

    Institute of Scientific and Technical Information of China (English)

    李骞; 胡龙; 饶雪飞; 悟永斌; 徐斌; 姜涛

    2015-01-01

    惣悦化铝为载体的某含钯废催化剂为原料,采用恿酸介质中添加悦化助浸剂的方案对钯恒择性浸出,并考察了焙烧,还原,浸出过程的适惚工惤条件。结果表明,钯的回收率可惣达到98%惣上。%Palladium was recovered from spent alumina-supported catalyst by the process of selective leaching using hydrochloric acid with an oxidant. The optimized conditions of roasting, reduction, leaching processes were also investigated. The results showed that the palladium recovery ratio was over 98% in the optimum condition.

  4. Experimental Investigation and Characterization of Fe and Al from Red Mud by Hydrochloric Acid%赤泥酸浸出铁、铝的工艺条件研究及其表征

    Institute of Scientific and Technical Information of China (English)

    吴烈善; 苏翠翠; 吕宏虹; 曾冬梅; 莫小荣

    2014-01-01

    The systematic study of leaching red mud with hydrochloric acid is carried out .The microstructure and phase transformation of red mud is analyzed by means of SEM and XRD .The experiment results show that the leaching ratios of Fe and Al are 82% and 30 .5% respectively under the condition that reaction temperature 80℃ ,liquid to solid ratio 6 ,hy-drochloric acid concentration 7mol/L and reaction time 3h .Microstructure of red mud is transformed from granular into layer frame shape after been leached by HCl .The hematite in red mud has been totally leached by HCl .%对广西某铝厂的赤泥进行了盐酸浸出铁、铝的工艺条件研究,并利用扫描电镜和X-衍射对赤泥酸溶前后的形貌特征及矿物物像、化学成分进行分析表征,研究结果表明,赤泥在温度为80℃、液固比为6、浓度为7 mol/L的盐酸中反应3 h ,Fe和Al的浸出率分别为82%和30.5%;酸溶前后赤泥形貌由团粒状转变为层架状,赤泥中赤铁矿矿物相被盐酸充分溶出。

  5. Synthesis of imidazoline-based dissymmetric bis-quaternary ammonium gemini surfactant and its inhibition mechanism on Q235 steel in hydrochloric acid medium

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J.; Gong, X.L.; Song, W.W.; Jiang, B.; Du, M. [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao, Shandong Province (China)

    2012-07-15

    An imidazoline-based dissymmetric bis-quaternary ammonium gemini surfactant has been synthesized. Its surface active properties at equilibrium in water at 25 C were determined. The inhibitive effect of the compound on Q235 steel in 1 M hydrochloric solution was investigated by the weight-loss method, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) analysis, and quantum chemical calculations. The results indicate that the compound has high surface properties and the inhibition efficiency (IE) increases with the increase in inhibitor concentration, which attain the maximum value around the CMC value. The imidazoline-based dissymmetric bis-quaternary ammonium acts as a mixed type inhibitor mainly inhibiting the cathodic processes and does not change the mechanism of either hydrogen evolution reaction or mild steel dissolution. The best IE is obtained at the immersion time of 144 h. The adsorption of the studied inhibitor on Q235 steel can be fitted to a Langmuir isotherm and the adsorption process is a spontaneous chemical adsorption. Quantum chemistry calculation results show that the imidazoline ring and heteroatoms of N, O, are the active sites of the inhibitors. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. dLocAuth: a dynamic multifactor authentication scheme for mCommerce applications using independent location-based obfuscation

    Science.gov (United States)

    Kuseler, Torben; Lami, Ihsan A.

    2012-06-01

    This paper proposes a new technique to obfuscate an authentication-challenge program (named LocProg) using randomly generated data together with a client's current location in real-time. LocProg can be used to enable any handsetapplication on mobile-devices (e.g. mCommerce on Smartphones) that requires authentication with a remote authenticator (e.g. bank). The motivation of this novel technique is to a) enhance the security against replay attacks, which is currently based on using real-time nonce(s), and b) add a new security factor, which is location verified by two independent sources, to challenge / response methods for authentication. To assure a secure-live transaction, thus reducing the possibility of replay and other remote attacks, the authors have devised a novel technique to obtain the client's location from two independent sources of GPS on the client's side and the cellular network on authenticator's side. The algorithm of LocProg is based on obfuscating "random elements plus a client's data" with a location-based key, generated on the bank side. LocProg is then sent to the client and is designed so it will automatically integrate into the target application on the client's handset. The client can then de-obfuscate LocProg if s/he is within a certain range around the location calculated by the bank and if the correct personal data is supplied. LocProg also has features to protect against trial/error attacks. Analysis of LocAuth's security (trust, threat and system models) and trials based on a prototype implementation (on Android platform) prove the viability and novelty of LocAuth.

  7. Analysis of twenty phenolic compounds in human urine: hydrochloric acid hydrolysis, solid-phase extraction based on K2CO 3-treated silica, and gas chromatography tandem mass spectrometry.

    Science.gov (United States)

    Lu, Dasheng; Feng, Chao; Wang, Dongli; Lin, Yuanjie; Ip, Ho Sai Simon; She, Jianwen; Xu, Qian; Wu, Chunhua; Wang, Guoquan; Zhou, Zhijun

    2015-05-01

    This study developed a new method for the analysis of 20 phenolic compounds in human urine. The urine samples were prepared by hydrochloric acid (HCl) hydrolysis, liquid-liquid extraction (LLE), and solid-phase extraction (SPE) cleanup. We found that HCl hydrolysis is of similar effectiveness to, and much cheaper than, the traditional enzymatic method. Vanillic acid was co-eluted with butyl paraben and interfered with the determination of butyl paraben in urine. K2CO3-treated-silica-gel SPE was designed to efficiently eliminate interference from the endogenous organic acids (especially vanillic acid) in urine. After derivatization, the samples were analyzed by large-volume-injection gas chromatography-tandem mass spectrometry (LVI-GC-MS-MS). Good linearity (R (2) ≥ 0.996) was established in the range 0.1-100 ng mL(-1) for all analytes. Method detection limits (MDLs) were 0.7-9.8 pg mL(-1). Intraday (n = 5) and interday (n = 5 days) validation was performed, with satisfactory accuracy (recovery: 70-126 % and 73-107 %, respectively) and precision (RSD ≤ 19 %) at two levels (low: 0.1 and 0.5 ng mL(-1); high: 5 and 10 ng mL(-1)). The method was used in a population study and achieved more than 85 % detection for most analytes; mean analyte concentrations were in the range 0.01-185 ng mL(-1). The method is suitable for the analysis of multiple phenolic metabolites in human urine.

  8. Analytical correlation between varying corrosion parameters and corrosion rate of Al-4.5Cu/10%ZrSiO{sub 4} composite in hydrochloric acid by rare earth chloride

    Energy Technology Data Exchange (ETDEWEB)

    Oloche, O.B.; Yaro, S.A. [Department of Metallurgical Engineering Ahmadu Bello University, Zaria (Nigeria); Okafor, E.G. [Department of Metallurgical Engineering Ahmadu Bello University, Zaria (Nigeria)], E-mail: ekeneokafor@yahoo.com

    2009-03-20

    The effect of varying temperature, time and inhibitor concentration on the corrosion rate of Al-4.5Cu/ZrSiO{sub 4} composite in 0.5 M hydrochloric acid without and with lanthanide chloride salt have been investigated. 10%ZrSiO{sub 4} was used for the production of the Al-4.5Cu/zircon sand composite. The time, temperature and concentration of inhibitor were varied in the range of 6-10 h at 2 h interval, 30-75 deg. C at 15 deg. C interval and 250-1000 ppm at 250 ppm interval respectively. Factorial design, standard deviation, effect of variables at 95% confidence interval and Arrhenius kinetics approach were used to correlate the corrosion parameter and corrosion rate. Results show that increase in temperature, inhibitor concentration above 250 ppm and decrease in time enhance corrosion rate. Also, temperature and anti-corrosion agent concentration are the most important control parameters. The kinetic and statistical approaches were in good agreement.

  9. Synthesis and characterization of a novel eco-friendly corrosion inhibition for mild steel in 1 M hydrochloric acid

    Science.gov (United States)

    Al-Amiery, Ahmed A.; Binti Kassim, Fatin A.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar

    2016-01-01

    The acid corrosion inhibition process of mild steel in 1 M HCl by azelaic acid dihydrazide has been investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, open circuit potential (OCP) and electrochemical frequency modulation (EFM). Azelaic acid dihydrazide was synthesized, and its chemical structure was elucidated and confirmed using spectroscopic techniques (infrared, nuclear magnetic resonance and mass spectroscopy). Potentiodynamic polarization studies indicate that azelaic acid dihydrazide is a mixed-type inhibitor. The inhibition efficiency increases with increased inhibitor concentration and reaches its maximum of 93% at 5 × 10−3 M. The adsorption of the inhibitor on a mild steel surface obeys Langmuir’s adsorption isotherm. The effect of temperature on corrosion behavior in the presence of 5 × 10−3 M inhibitor was studied in the temperature range of 30–60 °C. The results indicated that inhibition efficiencies were enhanced with an increase in concentration of inhibitor and decreased with a rise in temperature. To inspect the surface morphology of inhibitor film on the mild steel surface, scanning electron microscopy (SEM) was used before and after immersion in 1.0 M HCl. PMID:26795066

  10. Synthesis and characterization of a novel eco-friendly corrosion inhibition for mild steel in 1 M hydrochloric acid

    Science.gov (United States)

    Al-Amiery, Ahmed A.; Binti Kassim, Fatin A.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar

    2016-01-01

    The acid corrosion inhibition process of mild steel in 1 M HCl by azelaic acid dihydrazide has been investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, open circuit potential (OCP) and electrochemical frequency modulation (EFM). Azelaic acid dihydrazide was synthesized, and its chemical structure was elucidated and confirmed using spectroscopic techniques (infrared, nuclear magnetic resonance and mass spectroscopy). Potentiodynamic polarization studies indicate that azelaic acid dihydrazide is a mixed-type inhibitor. The inhibition efficiency increases with increased inhibitor concentration and reaches its maximum of 93% at 5 × 10-3 M. The adsorption of the inhibitor on a mild steel surface obeys Langmuir’s adsorption isotherm. The effect of temperature on corrosion behavior in the presence of 5 × 10-3 M inhibitor was studied in the temperature range of 30-60 °C. The results indicated that inhibition efficiencies were enhanced with an increase in concentration of inhibitor and decreased with a rise in temperature. To inspect the surface morphology of inhibitor film on the mild steel surface, scanning electron microscopy (SEM) was used before and after immersion in 1.0 M HCl.

  11. The Formation of Mathematical Model for CaCl2 Derived from The Reaction of Ulexite and Hydrochloric Acid by Using Full Factorial Desing Method

    OpenAIRE

    DURAK, Halil; GENEL, Yasar; BASHIROV, Novruz; KERIMOV, Genber

    2011-01-01

    One of the significant boron compounds which are common substance in nature is ulexite. Ulexite is a sodium calcium boron hydrate, its chemical formula is Na2O2CaO5B2O316H2O , and it is thick with in Turkey. Lots of products are derived from boron minerals. One of them is boric acid. CaCl2 is used in many fields and this compound can be obtained by different processes. The aim of this study is producing CaCl2 by forming mathematical model for CaCl2 composing in the wake of the interaction of ...

  12. The Formation of Mathematical Model for CaCl2 Derived from The Reaction of Ulexite and Hydrochloric Acid by Using Full Factorial Desing Method

    OpenAIRE

    DURAK, Halil; GENEL, Yasar; BASHIROV, Novruz; KERIMOV, Genber

    2013-01-01

    One of the significant boron compounds which are common substance in nature is ulexite. Ulexite is a sodium calcium boron hydrate, its chemical formula is Na2O2CaO5B2O316H2O , and it is thick with in Turkey. Lots of products are derived from boron minerals. One of them is boric acid. CaCl2 is used in many fields and this compound can be obtained by different processes. The aim of this study is producing CaCl2 by forming mathematical model for CaCl2 composing in the wake of the interaction of ...

  13. Application of Stabilized Silver Nanoparticles as Thin Films as Corrosion Inhibitors for Carbon Steel Alloy in 1 M Hydrochloric Acid

    Directory of Open Access Journals (Sweden)

    Ayman M. Atta

    2013-01-01

    Full Text Available Nanometer scaled materials have attracted tremendous interest as corrosion protective films due to their high ability to form self-assembled films on the metal surfaces. It is well known that the silver nanoparticles have higher reactivity towards aqueous acidic solution. The present work aims to prepare coated silver nanoparticles to protect carbon steel alloys from aqueous acidic corrosive media. In this respect, Ag nanoparticles colloid solutions were produced through reducing AgNO3 separately with trisodium citrate in an aqueous solution or in the presence of stabilizer such as poly(ethylene glycol thiol and poly(vinyl pyrrolidone. The morphology of the modified silver nanoparticles was investigated by TEM and DLS. UV-Vis absorption spectrum was used to study the effect of HCl on the stability of the dispersed silver nanoparticles. The corrosion inhibition efficiency of the poly (ethylene glycolthiol, the self-assembled monolayers of Ag nanoparticles, was determined by polarization method and electrochemical impedance spectroscopy (EIS. Polarization curves indicated that the coated silver poly (ethylene glycolthiol acted as a mixed type inhibitor. The data of inhibition efficiencies obtained measured by polarization measurements are in good agreement with those obtained with electrochemical impedance.

  14. Electrochemical, quantum chemical and SEM investigation of the inhibiting effect and mechanism of ciprofloxacin, norfloxacin and ofloxacin on the corrosion for mild steel in hydrochloric acid

    Institute of Scientific and Technical Information of China (English)

    PANG XueHui; GUO Wenduan; LI WeiHua; XIE dianDong; HOU BaoRong

    2008-01-01

    The inhibiting effect and mechanism of 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylicacid(ciprofloxacin), 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid (norfloxacin) and (-)-(S)-9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7oxo-7 H-pyrido(1,2,3-de)-1,4-benzoxazine-6 carboxylic acid (ofloxacin) on the corrosion of mild steel in 1 mol/L HCl have been studied using electrochemical method, quantum chemical method and SEM at 303 K. The potentiodynamic results showed that these compounds suppressed both cathodic and anodic processes of mild steel corrosion in 1 mol/L HCl. The impedance spectroscopy showed that Rp values increased, and Cdl values decreased with the rising of the working concentration. Quantum chemical calculation showed that there was a positive correlation between some inhibitors structure properties and the inhibitory efficiency. The inhibitors function through adsorption followed Langmuir isotherm, and chemisorption made more contribution to the adsorption of the inhibitors on the steel surface compared with physical adsorption. SEM analysis suggested that the metal had been protected from aggressive corrosion because of the addition of the inhibitors.

  15. Electrochemical, quantum chemical and SEM investigation of the inhibiting effect and mechanism of ciprofloxacin, norfloxacin and ofloxacin on the corrosion for mild steel in hydrochloric acid

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The inhibiting effect and mechanism of 1-cyclopropyl-6-fluoro-1,4-dihydro -4-oxo-7-(1-piperazinyl) -3- quinoline carboxylicacid(ciprofloxacin), 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid (norfloxacin) and (?)-(S)-9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7- oxo-7 H-pyrido(1,2,3-de)-1,4- benzoxazine-6 carboxylic acid (ofloxacin) on the corrosion of mild steel in 1 mol/L HCl have been studied using electrochemical method, quantum chemical method and SEM at 303 K. The potentiodynamic results showed that these compounds suppressed both cathodic and an-odic processes of mild steel corrosion in 1 mol/L HCl. The impedance spectroscopy showed that Rp values increased, and Cdl values decreased with the rising of the working concentration. Quantum chemical calculation showed that there was a positive correlation between some inhibitors structure properties and the inhibitory efficiency. The inhibitors function through adsorption followed Langmuir isotherm, and chemisorption made more contribution to the adsorption of the inhibitors on the steel surface compared with physical adsorption. SEM analysis suggested that the metal had been protected from aggressive corrosion because of the addition of the inhibitors.

  16. The water soluble composite poly(vinylpyrrolidone–methylaniline: A new class of corrosion inhibitors of mild steel in hydrochloric acid media

    Directory of Open Access Journals (Sweden)

    R. Karthikaiselvi

    2017-02-01

    Full Text Available In recent years poly methyl aniline has been reported as one of the efficient corrosion inhibitors of mild steel in acidic media. In view of the major limitation of the insolubility of polymethyl aniline PMA, we propose to convert PMA into a water soluble composite using supporting polymer polyvinylpyrrolidone to get higher solubility and corrosion inhibition efficiency. The water soluble composite poly(vinylpyrrolidone-methyl aniline was synthesized by chemical oxidative polymerization and its inhibitive effect on mild steel in 1 M HCl has been investigated using weight loss and electrochemical techniques (potentiodynamic polarization studies and impedance spectroscopy. SEM and EDX analyses are carried out to establish a protective film formation on the metal surface.

  17. Inhibition Effects of a Synthesized Novel 4-Aminoantipyrine Derivative on the Corrosion of Mild Steel in Hydrochloric Acid Solution together with Quantum Chemical Studies

    Directory of Open Access Journals (Sweden)

    Abu Bakar Mohamad

    2013-06-01

    Full Text Available 1,5-Dimethyl-4-((2-methylbenzylideneamino-2-phenyl-1H-pyrazol-3(2H-one (DMPO was synthesized to be evaluated as a corrosion inhibitor. The corrosion inhibitory effects of DMPO on mild steel in 1.0 M HCl were investigated using electrochemical impedance spectroscopy (EIS, potentiodynamic polarization, open circuit potential (OCP and electrochemical frequency modulation (EFM. The results showed that DMPO inhibited mild steel corrosion in acid solution and indicated that the inhibition efficiency increased with increasing inhibitor concentration. Changes in the impedance parameters suggested an adsorption of DMPO onto the mild steel surface, leading to the formation of protective films. The novel synthesized corrosion inhibitor was characterized using UV-Vis, FT-IR and NMR spectral analyses. Electronic properties such as highest occupied molecular orbital energy, lowest unoccupied molecular orbital energy (EHOMO and ELUMO, respectively and dipole moment (μ were calculated and discussed. The results showed that the corrosion inhibition efficiency increased with an increase in the EHOMO values but with a decrease in the ELUMO value.

  18. A Comparative Study of the Inhibitory Effect of Gum Exudates from Khaya senegalensis and Albizia ferruginea on the Corrosion of Mild Steel in Hydrochloric Acid Medium

    Directory of Open Access Journals (Sweden)

    Paul Ocheje Ameh

    2015-01-01

    Full Text Available A comparative study of the inhibitory potentials of gum exudates from Albizia ferruginea (AF and Khaya senegalensis (KS on the corrosion of mild steel in HCl medium was investigated using weight loss and gasometric method. The active chemical constituents of the gum were elucidated using GC-MS while FTIR was used to identify the bonds/functional groups in the gums. The two gum exudates were found to be good corrosion inhibitors for mild steel in acidic medium. On comparison, maximum inhibition efficiency was found in Khaya senegalensis with 82.56% inhibition efficiency at 0.5% g/L concentration of the gum. This may be due to the fact that more compounds with heteroatoms were identified in the GCMS spectrum of KS gum compared to the AF gum. The presence of such compounds may have enhanced their adsorption on the metal surface and thereby blocking the surface and protecting the metal from corrosion. The adsorption of the inhibitors was found to be exothermic and spontaneous and fitted the Langmuir adsorption model.

  19. Inhibition effects of a synthesized novel 4-aminoantipyrine derivative on the corrosion of mild steel in hydrochloric acid solution together with quantum chemical studies.

    Science.gov (United States)

    Junaedi, Sutiana; Al-Amiery, Ahmed A; Kadihum, Abdulhadi; Kadhum, Abdul Amir H; Mohamad, Abu Bakar

    2013-06-04

    1,5-Dimethyl-4-((2-methylbenzylidene)amino)-2-phenyl-1H-pyrazol-3(2H)-one (DMPO) was synthesized to be evaluated as a corrosion inhibitor. The corrosion inhibitory effects of DMPO on mild steel in 1.0 M HCl were investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, open circuit potential (OCP) and electrochemical frequency modulation (EFM). The results showed that DMPO inhibited mild steel corrosion in acid solution and indicated that the inhibition efficiency increased with increasing inhibitor concentration. Changes in the impedance parameters suggested an adsorption of DMPO onto the mild steel surface, leading to the formation of protective films. The novel synthesized corrosion inhibitor was characterized using UV-Vis, FT-IR and NMR spectral analyses. Electronic properties such as highest occupied molecular orbital energy, lowest unoccupied molecular orbital energy (EHOMO and ELUMO, respectively) and dipole moment (μ) were calculated and discussed. The results showed that the corrosion inhibition efficiency increased with an increase in the EHOMO values but with a decrease in the ELUMO value.

  20. Effects from pretreatment of stannous fluoride versus sodium fluoride on enamel exposed to 0.1 M or 0.01 M hydrochloric acid.

    Science.gov (United States)

    Willumsen, Tiril; Ogaard, Bjørn; Hansen, Bjørn Frode; Rølla, Gunnar

    2004-10-01

    Preventing enamel erosions caused by acidic soft drinks or from vomiting during eating disorders is a challenge in current dental research. The aim of this study was to examine whether pretreatment of dental enamel with a solution of 0.4% SnF2 could prevent dissolution of human enamel exposed to solutions of 0.1 M HCl, pH 1.2 or 0.01 M HCl at pH 2.2. Human enamel was pretreated for 18 h with a solution of 0.4% SnF2 and with control solutions of 2% NaF or distilled water, and then exposed to HCl solutions. Similar experiments were performed with teeth treated for 2 min SnF2 and then 4 min HCl. The effect was monitored by scanning electron microscopy (SEM) and by chemical analysis. At pH 2.2, NaF and water treatments showed minor inhibition of enamel dissolution, whereas SnF2 inhibited demineralization significantly also after 2 min pretreatment and 4 min HCl exposure. At pH 1.2, SEM showed severe dissolution of the enamel surfaces regardless of pretreatment. As pH of stomach vomit is usually > 1.5, SnF2 may be an interesting agent for use in the treatment and prevention of dental erosions even in patients with frequent vomiting episodes.

  1. Synergistic inhibition effect of L-phenylalanine and rare earth Ce(IV) ion on the corrosion of copper in hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Daquan, E-mail: zhangdaquan@shiep.edu.cn [Department of Environmental Engineering, Shanghai University of Electric Power, Shanghai 200090 (China); Wu Huan; Gao Lixin [Department of Environmental Engineering, Shanghai University of Electric Power, Shanghai 200090 (China)

    2012-04-16

    Highlights: Black-Right-Pointing-Pointer Synergistic effect of L-phenylalanine (L-Phe) and Ce(SO{sub 4}){sub 2} on the corrosion of copper on the corrosion inhibition of copper in 0.5 M HCl solution. Black-Right-Pointing-Pointer Structure of the complex film formed by the interaction of L-phenylalanine (L-Phe) and Ce(SO{sub 4}){sub 2} on the copper surface. Black-Right-Pointing-Pointer Mechanism of the improvement of the inhibition property of amino acids by the addition of rare earth compound. - Abstract: The synergistic inhibition effect of L-phenylalanine (L-Phe) and Ce(SO{sub 4}){sub 2} on the corrosion of copper in 0.5 M HCl solution was investigated by weight-loss, electrochemical methods and surface analysis. The electrochemical results showed that L-Phe has definite inhibition effects for copper, while Ce(IV) promoted the anodic process of copper corrosion. The combination L-Phe with Ce(IV) ion produced strong synergistic effect on corrosion inhibition for copper. The maximum inhibition efficiency was 82.7% for 5 mM L-Phe + 2 mM Ce(IV). The results of EIS and potentiodynamic polarization are in good agreement. SEM showed that L-Phe and Ce(IV) can form a dense protective film on the copper surface.

  2. 304 Cu抗菌不锈钢盐酸基酸洗工艺的研究%Research on hydrochloric acid-based pickling process of 304Cu antibacterial stainless steel

    Institute of Scientific and Technical Information of China (English)

    王冬; 邹德宁; 韩英; 薛清连

    2016-01-01

    为了明确盐酸基酸洗液对含Cu抗菌不锈钢表面氧化层的酸洗行为,采用正交试验法研究以盐酸为基础,Fe3+、H2 O2和HNO3为氧化剂的304Cu抗菌不锈钢酸洗工艺.并运用扫描电镜、透射电镜及电化学等手段分析经最佳配方酸洗后试样的表面形貌、成分及酸洗机理.结果表明:最佳酸洗工艺配方为HCl (36%~38%)120 ml/L、H2O2(30%)80 ml/L、FeCl3·6H2 O 20g/L、HNO310 ml/L,酸洗温度30℃,酸洗时间15 min.经该配方酸洗后材料表面平整度和光亮度较好,具有抗菌性能的点状ε-Cu相在基体上弥散分布.材料经酸洗去除氧化层后,仍具有足够含量的抗菌元素Cu存在.酸洗脱除氧化层过程由电荷传递过程控制,该酸洗液对不锈钢具有孔蚀诱导性,酸洗时间不宜过长.%In order to clarify pickling process of hydrochloric acid lotion against Cu⁃contained surface oxide layer of antibacterial stainless steel, the pickling process of 304Cu antibacterial stainless steel by using Fe3+, H2 O2 and HNO3 as the oxidants and taking hydrochloric acid as basis was studied by orthogonal experiment. And the surface morphology, composition and pickling mechanism of samples were analyzed by scanning electron microscopy, transmission electron microscopy and electrochemical after the best recipe pickling. The results show that the best pickling recipe is HCl (36%~38%) 120 ml/L, H2O2(30%) 80 ml/L, FeCl3· 6H2 O 20 g/L , HNO3 10 ml/L, pickling temperature is 30 ℃ and pickling for 15 min. The flatness and brightness of material surface are better after pickling, and antimicrobial properties of dot ε-Cu phase is dispersed on the substrate. After pickling to remove oxide layer of material, it still has enough content of antibacterial element Cu. Pickling process of removing oxide layer is controlled by the charge transfer process, the pickling solution of stainless steel with pitting corrosion

  3. Newly synthesized salicylidene-4,4′-dimorpholine (SDM) assembled on nickel oxide nanoparticles (NiONPs) and its inhibitive effect on mild steel in 2 N hydrochloric acid

    Energy Technology Data Exchange (ETDEWEB)

    Wadhwani, Poonam M. [Department of Chemistry, School of Sciences, Gujarat University, Ahmedabad 380009, Gujarat (India); Panchal, Vikram K., E-mail: vikram60panchal@gmail.com [R.G. Shah Science College, Vasna, Ahmedabad 382170, Gujarat (India); Shah, Nisha K. [Department of Chemistry, School of Sciences, Gujarat University, Ahmedabad 380009, Gujarat (India)

    2015-03-15

    Graphical abstract: - Highlights: • Nanoparticles with inhibitor were found to be better corrosion inhibitor than only organic compound. • A strong binding mechanism was confirmed by FTIR, PXRD. • Inhibition efficiency increases drastically for SDM assembled on NiONPs as compared to SDM. • The adsorption model obeys Langmuir adsorption isotherm. • The protective layer over the surface of mild steel has been confirmed by AFM analysis. - Abstract: Corrosion inhibition of mild steel in hydrochloric acid solution by salicylidene-4,4′-dimorpholine (SDM) and SDM assembled on nickel oxide nanoparticles (NiONPs) has been studied with gravimetric, electrochemical impedance spectroscopy (EIS) and polarization techniques. Inhibition was found to increase with increasing concentration of the inhibitors. While studying the temperature effect on corrosion behaviour of SDM and SDM assembled on NiONPs, the inhibition efficiency decreases for SDM only but increases for SDM assembled on NiONPs. The adsorption of both the inhibitors on the mild steel surface obeys the Langmuir adsorption isotherm. The activation energy as well as other thermodynamic parameters (ΔH* and ΔS*) for the inhibition process was calculated. EIS analysis results showed that the capacitive loops for SDM assembled on NiONPs were far away from blank when compared with SDM only. Polarization curve shows that the inhibitors are of mixed type. Further, the protective layer formation was confirmed from atomic force microscopy (AFM) results. Various methods such as EIS-MS, {sup 1}H NMR, XRD, FTIR, and DLS were performed for the confirmation of the structure, interaction of SDM with NiONPs and size of NiONPs.

  4. ac impedance, X-ray photoelectron spectroscopy and density functional theory studies of 3,5-bis(n-pyridyl)-1,2,4-oxadiazoles as efficient corrosion inhibitors for carbon steel surface in hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Outirite, Moha; Lagrenee, Michel; Lebrini, Mounim [Unite de Catalyse et de Chimie du Solide, UMR-CNRS 8181, ENSCL, B.P. 90108, F-59652 Villeneuve d' Ascq Cedex (France); Traisnel, Michel; Jama, Charafeddine [Laboratoire des Procedes d' Elaboration des Revetements Fonctionnels, PERF UMR-CNRS 8008, ENSCL, B.P. 90108, F-59652 Villeneuve d' Ascq Cedex (France); Vezin, Herve [Laboratoire de Chimie Organique et Macromoleculaire, UMR-CNRS 8009, USTL Bat C4, F-59655 Villeneuve d' Ascq Cedex (France); Bentiss, Fouad, E-mail: fbentiss@enscl.f [Laboratoire de Chimie de Coordination et d' Analytique, Faculte des Sciences, Universite Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco)

    2010-02-01

    The corrosion inhibition properties of a new class of oxadiazole derivatives, namely 3,5-bis(n-pyridyl)-1,2,4-oxadiazoles (n-DPOX) for C38 carbon steel corrosion in 1 M HCl medium were analysed by electrochemical impedance spectroscopy (EIS). An adequate structural model of the interface was used and the values of the corresponding parameters were calculated and discussed. The experimental results showed that these compounds are excellent inhibitors for the C38 steel corrosion in acid solution and that the protection efficiency increased with increasing the inhibitors concentration. Electrochemical impedance data demonstrate that the addition of the n-DPOX derivatives 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. Adsorption of these inhibitors on the steel surface obeys to the Langmuir adsorption isotherm. X-ray photoelectron spectroscopy (XPS) and the thermodynamic data of adsorption showed that inhibition of steel corrosion in normal hydrochloric solution by n-DPOX is due to the formation of a chemisorbed film on the steel surface. Quantum chemical calculations using the Density Functional Theory (DFT) and the Quantitative Structure Activity Relationship (QSAR) approach were performed on n-DPOX derivatives to determine the relationship between molecular structure and their inhibition efficiencies. The results of the quantum chemical calculations and experimental inhibition efficiency were subjected to correlation analysis and indicate that their inhibition effect is closely related to E{sub HOMO}, E{sub LUMO}, and dipole moment (mu).

  5. 桑叶提取物中槲皮素和山萘酚的含量测定%Determination of quercetin and kaempferol in folium mori extract after hydrolysis by hydrochloric acid

    Institute of Scientific and Technical Information of China (English)

    蒋立娣; 宣贵达; 吴好好; 李丽萍

    2009-01-01

    To establish an method to determine the contents of quercetin and kaempferol in folium mori extract by HPLC,the flavones in folium mori extract were hydrolyted into quercetin and kaempferol with the mixed solution of methanol-hydrochloric acid.The contents of quercetin and kaempferol were determined by HPLC method,performed on Diamonsil C_u column with the mobile phase consisted of methanol -0.20% phosphoric acid solution (63·37).The flow rate was 1.0 mL·min~(-1),the UV wavelength was set at 370 nm.The linear ranges of quercetin and kaempferol were 0.84-26.8 μg·mL~(-1),0.44-14.2 μg · mL~(-1),respectively.The average recoveries of quercetin and kaempferol were 101.3%,99.5%.The method was accurate,reliable and with good reappearance for the determination of quercetin and kaempferol in folium mori extract.%建立HPLC法测定桑叶提取物中水解槲皮素和山萘酚的含量.先用甲醇-盐酸混合液(甲醇终浓度50%,盐酸终浓度2.0 mol·L~(-1))水解桑叶提取物中的黄酮类成分成槲皮素和山萘酚,以HPLC法测定槲皮素和山萘酚含量.色谱柱为Diamonsil钻石C18柱,流动相为甲醇-0.2%磷酸(63∶37,体积分数),流速为1.0 mL·min~(-1),检测波长为370 nm.结果表明槲皮素在0.84~26.8 mg·L~(-1)之间,山萘酚在0.44~14.2 mg·L~(-1)之间呈良好的线性关系,平均回收率分别为101.3%和99.5%.该测定方法准确、重复性好,可用于桑叶提取物中槲皮素和山萘酚的含量测定.

  6. 响应面法优化红薯渣果胶的提取条件%Optimization of hydrochloric acid-mediated extraction of pectin from yam pulpusing response surface methodology

    Institute of Scientific and Technical Information of China (English)

    张允; 王响; 陈劲春

    2012-01-01

    This study examined variables that influence the hydrochloric acid-extraction of pectins from yam pulp. An initial screening study tested the main parameters influencing yield and uronic acid content by one-factor-at-a-time experimental design. The solid-to-liquid ratio was determined to be 1:16. The studies of the relationship between the GalA yield and the three variables including extraction pH, temperature and the length of extraction time used response surface methodology using a Box-Behnken design. A mathematical model representing the relationship was constructed using quadratic regression orthogonal rotation combination design, and the effects of pairwise cross-interactions among the above factors on GalA yield were evaluated by response surface analysis. The optimal extraction conditions for the extraction of pectin from yam pulp were determined to be pH 1.5 at 90 % for 90 min. Under these optimal conditions, the yield of pectin reached up to 6.50%. In industry this study provide the basis of the extraction of pectins from yam pulp.%果胶提取以红薯渣为原料,果胶生产常用酸盐酸作为提取用酸,在单因素试验基础上,确定料液比为1:20,对提取液pH值,提取温度T,提取时间t3个因素采用响应面方法进行了工艺优化研究。经过响应面分析了因素之间的相互影响并建立了3因素与果胶提取率的二次回归模型。结果表明:盐酸提取果胶的最优工艺参数为:温度87℃、pH1.33、时间92min,在此最优提取条件下果胶的提取率为6.24%。这为工业利用红薯渣生产果胶提供了依据。

  7. Leachability of nitrided ilmenite in hydrochloric acid

    CSIR Research Space (South Africa)

    Swanepoel, JJ

    2010-10-01

    Full Text Available Titanium nitride in upgraded nitrided ilmenite (bulk of iron removed) can selectively be chlorinated to produce titanium tetrachloride. Except for iron, most other components present during this low temperature (ca. 200 °C) chlorination reaction...

  8. Propanoyl(1Z-N-(2,6-dimethylphenyl-2-oxopropanehydrazonoate as inhibitor for corrosion of 6061 Al alloy15 % (v SiC(p composite in hydrochloric acid media

    Directory of Open Access Journals (Sweden)

    Achutha Kini U

    2012-10-01

    Full Text Available ABSTRACT: The corrosion inhibition effect of Propanoyl(1Z-N-(2,6-dimethylphenyl-2-oxopropanehydrazonoate (PDOH in the corrosion of 6061 Aluminium alloy-15%(v SiC(p composite in 0.5 and 1M hydrochloric acid medium at four different temperatures (30, 40, 50 and 60 ⁰C was investigated using potentio-static polarization (Tafel extrapolation and Linear polarization and weight loss methods. The results obtained reveal that PDOH is an efficient corrosion inhibitor with around 96% inhibition efficiency within the range of temperature studied. Leftward and downward shifts in Tafel plots were observed with the addition of the inhibitor, indicating that PDOH inhibits the corrosion process effectively, and that it is a cathodic inhibitor. Corrosion rate increases and inhibition efficiency decreases with increase in temperature. Results obtained by Tafel extrapolation, linear polarization, and weight loss methods are in agreement. The adsorption of the inhibitor onto the surface of the 6061 Al alloy 15 % (v SiC(p composite is found to obey Temkins' adsorption isotherm that verifies the assumption of mono-layer adsorption on a uniform homogeneous composite surface with an interaction in the adsorption layer. The inhibition is therefore governed by the physisorption mechanism.ABSTRAK: Kesan perencatan kakisan Propanoyl(1Z-N-(2,6-dimethylphenyl-2-oxopropanehydrazonoate (PDOH ke atas kakisan komposit aloi Al 6061-15%(v SiC(p dalam media asid hidroklorik 0.5 dan 1M pada suhu-suhu yang berbeza (30, 40, 50 dan 60⁰C telah dikaji menggunakan polarisasi statik-upaya (extrapolarisasi Tafel dan polarisasi Linear dan kaedah kehilangan berat. Keputusan diperolehi menunjukkan PDOH adalah perencat yang efisien dengan 96 % keupayaan perencatan bagi julat suhu yag dikaji. Anjakan ke kiri dan ke bawah plot Tafel dapat dilihat dengan penambahan perencat, menunjukkan PDOH merencatkan proses kakisan dengan berkesan, dan ia adalah perencat katodik. Dengan peningkatan suhu

  9. Corrosion resistance and its mechanism of Ni-Cu-P coating and 316L stainless steel in hot hydrochloric acid solution%Ni-Cu-P镀层和316L不锈钢在热盐酸溶液中的耐蚀性及机制

    Institute of Scientific and Technical Information of China (English)

    薛亚军

    2013-01-01

    Effect of temperature and concentration on the corrosion behavior of Ni-Cu-P coating and 316L stainless steel was studied by mass loss method.The results show that the corrosion resistance of Ni-Cu-P coating is better than that of 316L stainless steel in hot hydrochloric acid solution.The effect of hydrochloric acid concentration on the corrosive rate of 316L stainless steel is greater than that of Ni-Cu-Pcoating.The corrosive rates of 316L stainless steel and Ni-Cu-P coating increase 2.7 and 0.6 times respectively while increasing hydrochloric acid concentration from 5% to 20%.For the Ni-Cu-P coating,the uniform corrosion occurs in the hydrochloric acid solution.However,the selective corrosion mechanism is found for 316L stainless steel,and the higher temperature and concentration of corrosion medium,the more serious selective corrosion.%采用质量损失法研究了温度和浓度对化学镀Ni-Cu-P镀层和316L不锈钢在盐酸溶液中的腐蚀行为.结果表明,在高温盐酸溶液中,Ni-Cu-P镀层的耐蚀性优于316L不锈钢,盐酸浓度对316L不锈钢腐蚀速率的影响大于Ni-Cu-P镀层,盐酸浓度由5%升高到20%,316L不锈钢和Ni-Cu-P镀层的腐蚀速率分别增大了2.7倍和0.6倍;在盐酸溶液中,Ni-Cu-P镀层发生均匀腐蚀,316L不锈钢发生选择性腐蚀,且温度和浓度越高,选择性腐蚀越严重.

  10. Spectrophotometric Determination of Scandium in Hydrochloric Acid Leaching Solution of Red Mud%赤泥盐酸浸出液中钪的分光光度测定

    Institute of Scientific and Technical Information of China (English)

    邓海霞; 王克勤; 王皓; 李爱秀; 张风林; 陈津

    2011-01-01

    考察了温度、时间、显色剂用量、酸度对待测溶液吸光度的影响,结果表明:温度对吸光度值不产生大的影响,在室温下测试即可;溶液显色在前8min内不稳定,其显色时间一定要达到10 min,溶液颜色保持16h不发生太大的变化;显色剂氯代磺酚C和Sc(Ⅲ)1∶1络合稳定,其溶液加入量确定为3ml;酸度对吸光度有较大的影响,待测溶液的pH值为2.0时吸光度值最大,且稳定.溶液最大吸光度波长为649 nm,工作曲线回归方程为y=0.03839x -0.0002,相关系数的平方为0.9993,Sc(Ⅲ)的质量浓度在0~1.2 mg·L-1范围内符合朗伯-比尔定律,表观摩尔吸光系数为7.78×105 L·mol -1·cm-1.本法测定赤泥盐酸浸出液中的钪,结果比较稳定,RSD(n =6)为1.45%~4.16%,加标回收率为98%~ 102%,灵敏度高、结果较满意.%The effects of temperature, time, reagent dosage, solution pH on absorbance showed that: the temperature had little effect on the absorbance, the solution could be tested at room temperature; the determination result was not stable within the first 8 min, the solution should achieve a coloration time for 10 mins, the solution color maintained 16 h did not change much; reagent chlorosulpho-phenol C and Sc( IB) 1:1 complex stability, the solution was added 3 ml; acidity had great influence on the absorbance with pH value of 2.0, the maximum absorbance, and stability. Hie maximum absorbance of solution was at 649 nm, and the standard curve regression equation: y = 0.03839* - 0.0002, the square of correlation coefficient was 0.9993, Lambert-Beer law was obeyed for Sc (JE ) in the range of 0 -1.2 rag-L"' and the apparent molar absorptivity was 7.78 xlO3 L-mol~1>cm~l. The method was applied to the determination of Sc( HI) in hydrochloric acid leaching solution of red mud, the result was stable with high sensitivity and satisfactory, RSD ( n = 6) was 1.45%-4.16% and the recovery of Sc( I) was 98% to 102%.

  11. Synthesis of N - Alkyl Benzimidazoles as Corrosion Inhibitors for Acidification in Hydrochloric Acid and Evaluation of Their Inhibition Performance%N-烷基苯并咪唑酸化缓蚀剂的合成及性能

    Institute of Scientific and Technical Information of China (English)

    杨鹏辉; 冀生辉

    2013-01-01

    Four kinds of N - alkyl benzimidazole corrosion inhibitors were synthesized by alkylation of 2 - methyl benzimidazole or 2 - ethyl benzimidazole. The corrosion inhibition performance of as - synthesized inhibitors was evaluated by static state weight loss test and dynamic potential scanning polarization curve measurement. It was found that properly extending carbon chain of benzimidazole helped to improve the anticorrosion ability of benzimidazoles, and corrosion inhibitor N - hexadecyl - 2 - ethyl benzimidazole showed the best corrosion inhibition performance. Besides, at 60 ℃ in 15% hydrochloric acid, the corrosion rate of N80 steel decreased with increasing concentration of the corrosion inhibitor; and the corrosion rate of the steel at a corrosion inhibitor concentration of 1.0% was 1.73g/(m2 · h) , which indicated that corrosion inhibitor N-hexadecyl-2-ethyl benzimidazole was advantageous over the first-class corrosion inhibitor for acidification. Moreover, as-synthesized corrosion inhibitors were a class of mixed-type inhibitors dominated by cathode inhibition, but their inhibition performance in HCl with a concentration of above 20 % or at a temperature of above 70 ℃ was undesirable.%苯并咪唑是一类环境友好的缓蚀剂,将其衍生物用作油气田酸化缓蚀剂的报道较少.通过烷基化反应在2-甲基苯并咪唑和2-乙基苯并咪唑的1-氮原子上分别引入十二烷基和十六烷基,合成了4种N-烷基苯并咪唑,并以其为主剂制成缓蚀剂,用静态失重法和动电位扫描极化曲线对4种复配缓蚀剂在盐酸溶液中的缓蚀性能进行了评价.结果表明:适当延长1位烷基碳链,有助于提高苯并咪唑衍生物的缓蚀能力;合成的4种N-烷基苯并咪唑中,以N-十六烷基-2-乙基苯并咪唑为主剂制成缓蚀剂d的缓蚀性能最好;在60℃,15%HCl中,N80钢的腐蚀速率随缓蚀剂d用量的增大而减小,其用量为1.0%时,N80钢腐蚀速率为1.73 g/(m2·h),优于

  12. 盐酸介质中N,N′-二(二苯基膦基)-1-苯乙胺对碳钢的缓蚀性能研究%Investigation on Corrosion Inhibition of N,N′-Bis(diphenylphosphino)-1-phenylethylamine for Carbon Steel in Hydrochloric Acid Solution

    Institute of Scientific and Technical Information of China (English)

    魏健; 谢斌; 赖川; 李玉龙; 邹立科; 樊义康

    2016-01-01

    目的:对N,N′-二(二苯基膦基)-1-苯乙胺( NPM)的合成、结构表征及其在盐酸介质中对碳钢的缓蚀性能进行研究。方法用红外光谱、元素分析和熔点测试等方法对NPM的结构进行表征,采用静态失重法、动电位极化曲线法和电化学阻抗法研究NPM在盐酸介质中对碳钢的缓蚀作用,研究腐蚀体系温度、HCl浓度、NPM浓度和腐蚀体系静置时间对NPM缓蚀率的影响,探讨NPM在碳钢表面上的吸附机理。结果动电位极化曲线法研究结果表明NPM是一种混合型缓蚀剂。 NPM的缓蚀率随NPM浓度的增加而增大,当NPM的质量浓度为140 mg/L时,NPM在25℃的1.0 mol/L HCl 溶液中的缓蚀率达到94.71%;NPM的缓蚀率随腐蚀体系温度的升高而降低,随HCl浓度的增大而减小,但随腐蚀体系静置时间的延长缓蚀率逐渐增大。 NPM在碳钢表面的吸附符合Langmuir吸附等温方程式,属于自发进行的物理和化学吸附。结论所合成的化合物NPM是一种高效的混合型有机缓蚀剂。%Objective To study the synthesis, structure characterization and inhibition performance of N,N′-bis( di-phenylphos-phino)-1-phenylethylamine ( NPM) on carbon steel in hydrochloric acid solution. Methods The structure of synthesized NPM was characterized by means of infrared spectroscopy, elemental analysis and melting point test. And the inhibitive efficiency of NPM on carbon steel in hydrochloric acid solution was investigated using the static weight loss method, potentiodynamic polarization curve and electrochemical impedance. The influences of the corrosion system temperature, NPM concentration, hydrochloric acid concen-tration and standing time of the corrosion system on the corrosion inhibition efficiency of NPM on carbon steel were studied, and the adsorption mechanism of NPM on carbon steel surface was also discussed. Results The potentiodynamic polarization curves indica-ted that NMP acted as a mixed-type inhibitor

  13. Experimental carcinogenesis on the oropharyngeal mucosa of rats with hydrochloric acid, sodium nitrate and pepsin Carcinogênese experimental na mucosa orofaríngea de ratos com ácido clorídrico, nitrato de sódio e pepsina

    Directory of Open Access Journals (Sweden)

    André Del Negro

    2008-08-01

    Full Text Available PURPOSE: To investigate the carcinogenic action of hydrochloric acid, pepsin and sodium nitrate on the oropharyngeal mucosa of rats, simulating the reflux of gastric contents. METHODS: Eighty-two Wistar rats were divided in seven groups and submitted to 2 or 3 weekly applications of hydrochloric acid, pepsin and sodium nitrate on the pharyngeal mucosa during six months. Study groups comprised 12 animals each. Rats in groups I and II were submitted to 2 (GI or 3 (GII weekly applications of 0.1N hydrochloric acid. Groups III and IV were submitted to 2 (GIII or 3 (GIV weekly applications of 0.1N hydrochloric acid solution with pepsin. Groups V and VI were submitted to 2 (GV or 3 (GVI weekly applications of 0.1N hydrochloric acid and treated with daily nitrate diluted in water. Group VII consisted of 10 animals submitted to 2 weekly applications of filtered water. RESULTS: No dysplasia, intra-epithelial neoplasia or invasive carcinomas were detected. Inflammatory changes were observed in varying degrees and mast cells were more common in Groups V and VI (p=0.006. CONCLUSION: The data of the current study could not corroborate the hypothesis that gastroesophageal and pharyngolaryngeal refluxes are carcinogenic factors to the laryngopharyngeal mucosa, and more studies are necessary in the future.OBJETIVO: Investigar a ação carcinogênica do ácido clorídrico, pepsina e nitrato de sódio na mucosa orofaríngea de ratos, simulando o refluxo do conteúdo gástrico à mucosa do faringo-laringea. MÉTODOS: Oitenta e dois ratos Wistar foram divididos em 7 grupos e submetidos a 2 ou 3 aplicações semanais de ácido clorídrico, pepsina e nitrato de sódio na mucosa orofaríngea durante 6 meses. Os grupos de estudo envolveram 12 animais cada. Os ratos nos grupos I e II foram submetidos à 2 (GI ou 3 (GII aplicações semanais de ácido clorídrico 0,1N. Nos grupos III e IV foram 2 (GIII ou 3 (GIV aplicações semanais de ácido clorídrico e pepsina. Nos

  14. Design of pH Measurement and Control System Using in Process of NdFeB Waste With Hydrochloric Acid%盐酸优溶法处理NdFeB废料pH测控系统的设计

    Institute of Scientific and Technical Information of China (English)

    周雄军; 逄启寿

    2014-01-01

    The leaching principle of NdFeB waste using hydrochloric acid is introduced .The pH controlling mathematical model for acid dissolving and neutralizating process are established based on leaching mechanism .The overall designing scheme of pH control system in leaching process is put forwarded .%介绍了盐酸优溶法处理NdFeB废料的原理。结合浸出机制,建立了酸溶、中和过程的pH控制数学模型,提出了浸出过程中pH控制系统的整体设计方案。

  15. 盐酸解析与水碱洗系统的酸、水生产平衡%Hydrochloric acid analysis and alkali washing system acid, water production balance

    Institute of Scientific and Technical Information of China (English)

    林涛海; 刘胜军

    2012-01-01

    以40万t/a PVC为例,对氯化氢的消耗量与盐酸的解析量进行了物料衡算。%Take 400 kt/a PVC as an example, calculating material balance between consumption of hydrogen chloride gas and resolving amount of hydrogen acid.

  16. 机械通气与盐酸氨溴索联合治疗老年急性呼吸窘迫综合症的临床效果%Mechanical Ventilation with Hydrochloric Acid Ammonia Bromine Cable Joint is the Clinical Effect of Treatment of Senile Acute Respiratory Distress Syndrome

    Institute of Scientific and Technical Information of China (English)

    张鹏

    2016-01-01

    目的:客观评价机械通气与盐酸氨溴索联合治疗老年急性呼吸窘迫综合症的临床效果。方法随机选择该院2012年1月—2015年12月接收的55例老年急性呼吸窘迫综合症患者(A组),同期选择55例老年急性呼吸窘迫综合症患者(B组)作对照,分别予以机械通气与盐酸氨溴索联合治疗、机械通气单纯治疗。结果 A组入选患者有效率81.82%,B组54.55%(P﹤0.05)。结论就老年急性呼吸窘迫综合症患者而言,选择机械通气与盐酸氨溴索联合治疗方案效果突出。%Objective To objectively evaluate mechanical ventilation with hydrochloric acid ammonia bromine cable joint is the clinical effect of treatment of senile acute respiratory distress syndrome. Methods Random selection etween January 2012 and December 2015 received 55 cases of elderly patients with acute respiratory distress syndrome (group A), at the same time choose 55 cases of elderly patients with acute respiratory distress syndrome (group B) were compared, respective-ly to mechanical ventilation with hydrochloric acid ammonia bromine cable joint treatment, mechanical ventilation therapy alone. Results In group A patients effective rate was 81.82%, 54.55% in group B (P﹤ 0.05). Conclusion In terms of el-derly patients with acute respiratory distress syndrome, mechanical ventilation and hydrochloric acid ammonia bromine joint treatment effect is prominent.

  17. Study of nano-Ti02 thin films prepared by sol-gel in the ethanol-hydrochloric acid-water system%乙醇-盐酸-水体系中溶胶-凝胶法制备纳米TiO2薄膜的研究

    Institute of Scientific and Technical Information of China (English)

    孟丹; 王和义; 刘秀华; 丁兰岚

    2011-01-01

    以Ti (OBu)4为前驱体,设计单因素优选实验,通过溶胶凝胶-浸渍提拉法在玻璃基片上制备TiO2纳米薄膜,研究了无水乙醇、浓盐酸、超纯水对其结构和性能的影响,获得了纳米TiO2薄膜的最佳制备条件.%The nano-Ti02 films on glass was prepared from Ti( OBu)4 precursor via the sol-gel and dip-coating method. The effects of anhydrous ethanol, hydrochloric acid and ultra-pure water on structures and performances of TiO2 films were investigated by single factor optimization,and the optimum preparation conditions of TiO2 thin films were obtained.

  18. 基于差分吸收激光雷达的一种新的对流层臭氧浓度反演算法%Butanol Extraction Combined with Dilute Hydrochloric Acid Dissolution-Atomic Fluorescence Spectrometric Method for Indirect Determination of Molybdenum in Chinese Herbal Medicine

    Institute of Scientific and Technical Information of China (English)

    范广强; 刘建国; 刘文清; 陆亦怀; 张天舒; 董云升; 赵雪松

    2012-01-01

    A method for indirectly determining the molybdenum in Chinese herbal medicine by butanol extraction and dilute hydrochloric acid dissolution was established for atomic fluorescence spectrometry. The molybdoarsenate heteropoly acid, formed in the presence of As( V) and ammonium molybdate in 0. 3 mol · L-1 sulphuric acid medium, was separated and enriched in the organic solvent, then the evaporation of organic reagent was implemented and the left residue was dissolved in dilute hydrochloric acid in which the arsenic content was determined on behalf of molybdenum. In the optimum experimental conditions, molybdenum content in 0~15 μg · L-1 range depicts a good linear relationship, the detection limit and relative standard deviation of 0. 44 μg · L-1 and 1.1% were obtained, respectively. Spiked Chinese herbal medicine samples were determined with the proposed method, and recoveries of 95. 6%—101. 3% were achieved.%差分吸收激光雷达探测对流层臭氧浓度时,气溶胶的干扰会造成较大的误差.提出了一种算法,该算法能够同时反演得到对流层臭氧浓度和气溶胶消光系数,减少气溶胶对反演结果的影响.使用实验数据,分析计算了气溶胶雷达比,气溶胶波长指数、标定点气溶胶后向散射比各种变化参数对反演结果的误差.结果表明,1km以下,各种变化参数造成的反演误差小于8%,1km以上臭氧浓度误差主要来源于信号和背景噪声,各种参数反演误差小于3%.最后给出了利用该算法得到对流层臭氧浓度和气溶胶的消光系数垂直廓线,并和传统的双波长差分算法反演结果作了比较分析.实验结果表明该算法是可行的,该算法可以减少气溶胶对差分吸收激光雷达测量结果引起的误差.

  19. Complex Leaching Process of Scheelite in Hydrochloric and Phosphoric Solutions

    Science.gov (United States)

    Liu, Liang; Xue, Jilai; Liu, Kang; Zhu, Jun; Wang, Zengjie

    2016-09-01

    The complex leaching process of synthetic scheelite and scheelite concentrate in hydrochloric and phosphoric solutions has been investigated for improving process efficiency. A higher leaching rate, compared with the classic acid leaching process, can be obtained through the synergy of HCl and H3PO4 with appropriate W/P mole ratio, temperature, and acid concentration. For synthetic scheelite, the optimum leaching conditions were W/P mole ratio 7:1, temperature 50°C, HCl 0.72 mol/L, and stirring speed 600 rpm; for scheelite concentrate, W/P mole ratio 7:1, temperature 80°C, HCl 2.16 mol/L, and stirring speed 1000 rpm. The leaching rates under the optimized conditions can reach up to 98% or even higher. FTIR spectra analysis confirmed that the leachate composition remained as H3[PW12O40] in the range of varying W/P mole ratios, so the PO4 3- in acidic solution and phosphorus content in the leaching product could be better controlled. The function 1 - (1 - X)1/3 against leaching time was applied to fit the experimental data, and the apparent activation energy, E a, was calculated as 60.65 kJ/mol. The results would be valuable for effectively using scheelite as a raw material resource for sustainable tungsten production.

  20. Dissolution kinetics of aluminum and iron from coal mining waste by hydrochloric acid☆

    Institute of Scientific and Technical Information of China (English)

    Li Cui; Yanxia Guo; Xuming Wang; Zhiping Du; Fangqin Cheng

    2015-01-01

    The extraction of aluminum from coal mining waste (CMW) is an important industrial process. The two major problems in applications are low aluminum dissolution efficiency and high iron content in the raw material, which affect the quantity and quality of products. To improve the aluminum recovery process, the leaching kinet-ics of CMW with hydrochloric acid was studied. A shrinking core model was used to investigate aluminum and iron dissolution kinetics. Based on the kinetic characteristics, a process for recovering aluminum was proposed and tested experimental y. It is found that the aluminum leaching reaction is controlled by surface reaction at low temperatures (40–80 °C) and by diffusion process at higher temperatures (90–106 °C). The iron dissolution process is dominated by surface reaction at 40–100 °C. The results show that iron could be dissolved or separated by concentrated hydrochloric acid. Fine grinding wil improve aluminum dissolution significantly.

  1. A study of the clinical effect of combining use of budesonide and hydrochloric acid ammonia bromine using of ultrasonic atomization inhalation on treatment of infantile capillary bronchitis%布地奈德和盐酸氨溴索联合使用超声雾化吸入治疗婴幼儿毛细支气管炎的疗效观察

    Institute of Scientific and Technical Information of China (English)

    王海丽

    2014-01-01

    Objective To study the clinical effect of combining use of budesonide and hydrochloric acid ammonia bromine using ultrasonic atomization on treatment of infantile capillary bronchitis. Methods 80 cases of patients in our hospital were selected,randomly divided into experimental group and control group,each 40 cases,the experimental group were given basic treatment plus budesonide and ambroxol hydrochloride using ultrasonic atomizing inhalation,Compared the disappeared time of clinical symptoms and signs and the cure rate of the two groups. Results The time of clinical symptoms and signs in the experimental group were shorter than that of the observation group,the cure rate in the experimental group was significantly higher than the control group. Conclusion Using budesonide and hydrochloric acid ammonia bromine with ultrasonic atomization inhalation on treatment of infantile capillary bronchitis,can effectively shorten the time of dyspnea,suppress wheezing (such as clinical symptoms and signs of time,and improve the cure rate.The clinical application of the treatment is safe and convenient,is worth to clinical promotion.%目的:探讨布地奈德和盐酸氨溴索合用使用超声雾化治疗婴幼儿毛细支气管炎的临床效果。方法选80例来我院就诊的患儿随机分为实验组和对照组,各40例,实验组在采取基础治疗外加用布地奈德+盐酸氨溴索使用超声雾化吸入治疗,对比两组患儿临床症状、体征消失时间以及治愈率。结果实验组临床症状、体征时间均比观察组时间短,并且治愈率也明显高于对照组。结论布地奈德和盐酸氨溴索联合使用超声雾化吸入治疗婴幼儿毛细支气管炎,可以有效缩短患儿呼吸困难、憋喘等临床症状和体征缓解时间,并且提高治愈率,对于临床应用安全方便,值得临床推广。

  2. Response Surface Methodology for Optimization of Extraction Process for Soluble Dietary Fiber from Grape Pomace with Hydrochloric Acid%响应面法优化葡萄皮渣中可溶性膳食纤维的酸法提取工艺

    Institute of Scientific and Technical Information of China (English)

    杜彬; 李凤英; 范长军; 朱凤妹

    2011-01-01

    目的:利用响应面法对葡萄皮渣中可溶性膳食纤维的酸法提取工艺进行优化。方法:在单因素试验基础上选取试验因素与水平,根据Box-Behnken试验设计原理采用四因素三水平的响应面分析法,依据回归分析确定各工艺条件的影响因素,以可溶性膳食纤维得率为响应值作响应面和等高线图。结果:在分析各个因素的显著性和交互作用后,得出葡萄皮渣可溶性膳食纤维提取的最佳工艺为盐酸的浓度0.40mol/L、提取温度75℃、提取时间90min、料液比1:12(g/mL),在此工艺条件下可溶性膳食纤维得率为47.56mg/g。结论:响应面回归方程与实验结果拟合性好,此模型合理可靠,可用于实际预测。%Objective: To optimize the extraction of soluble dietary fiber(SDF) from grape pomace with hydrochloric acid.Methods: One-factor-at-a-time experiments,mathematical modeling based on Box-Behnken experimental design and multiple regression analysis and response surface analysis were carried out to investigate the individual and interactive effects of various process conditions on extraction yield of SDF and their significance.Response surface and contour plots were drawn with extraction yield of SDF as a function.Results: The optimal conditions for SDF extraction were 0.40 mol/L hydrochloric acid as extraction solvent at a material-to-liquid ratio of 1:12(g/mL) and 75 ℃ for an extraction duration of 90 min.Under the optimal extraction conditions,the yield of SDF was up to 47.56 mg/g,which was close to the model-predicted value.Conclusion: The developed regression equation can be well fitted with experimental results and is reasonable,reliable and applicable for actual prediction.

  3. Research on Application of HPLC in Measuring Concentration of Hydrochloric Acid Palmatine in Rat Serum%高效液相色谱-荧光检测法在大鼠血清中盐酸黄藤素浓度测定中的应用研究

    Institute of Scientific and Technical Information of China (English)

    周小虎

    2015-01-01

    目的:建立大鼠血清中盐酸黄藤素浓度的反相高效液相色谱-荧光检测方法,并应用于大鼠口服盐酸黄藤素制剂后药物体内药动学过程测定。方法色谱条件:Diamonsil C18柱流动相:0.01mol/L 磷酸二氢钾缓冲液-乙腈(40:60);流速:1.0mL/min;荧光检测波长:λEx =310 nm,λEm =360 nm。动物实验:给予6只 wistar 大鼠口服盐酸黄藤素片,尾静脉取血测定血药浓度,数据经3P97药动学软件包处理,计算药物体内药动学参数。结果黄藤素线性回归方程为:C =6.1050A ×10-4+7.3×10-3(r =0.9997),盐酸黄藤素血清浓度在0.04mg/L -0.4mg/L 范围内与峰面积呈良好的线性关系。低、中、高3个浓度日内及日间精密度试验 RSD 均小于10%。稳定性良好(RSD =1.77%)。盐酸黄藤素在大鼠体内表现为两室模型药动学过程。按30mg/kg 剂量灌胃给药,测得血药浓度达峰时间为(0.30±0.04)h,血药峰浓度为15.27μg/L,消除速率常数为0.2031(1/h)。结论本研究建立的高效液相色谱-荧光检测大鼠血清中盐酸黄藤素浓度方法灵敏度高,专属性强,稳定性好,能快速、准确地测定大鼠血清中盐酸黄藤素浓度,适用于盐酸黄藤素新制剂大鼠体内过程实验的血清药物浓度测定。%s:Objective Establish reversed -phase high -performance liquid chromatography – fluorescence detection method of the hy -drochloric acid palmatine concentration in rat serum , and apply it in measuring the pharmacokinetics process in the medicine after the rat takes the hydrochloric acid palmatine preparations orally .Methods Chromatographic condition: Diamonsil C18 , mobile phase: 0.01mol /L monopotassium phosphate buffer solution :acetonitrile (40:60); flow velocity: 1.0mL/min; fluorescence detection wave length :λEx =310nm,λEm =360nm.Animal experiment: let 6 wistar rats

  4. Determination of silver in miscellaneous copper materials in hydrochloric acid medium by ammonia leaching-flame atomic absorption spectrometry%氨水浸取-盐酸介质火焰原子吸收光谱法测定杂铜物料中的银

    Institute of Scientific and Technical Information of China (English)

    肖红新

    2014-01-01

    The sample is dissolved in aqua regia and silver is leached by ammonia ,most other metallic elements are precipitated at the same time ,eliminating the interference .In 10%hydrochloric acid medium ,under the set equip-ment working conditions ,silver content was determined by flame atomic absorption spectrometry .The relatively stand-ard deviation of the determination results is less than 1 %.%采用王水溶解样品,氨水浸取银,同时沉淀分离大部分其他金属元素,消除其他元素干扰;在10%的盐酸介质中,在设定的仪器工作条件下,采用火焰原子吸收光谱法测定杂铜物料中的银。该方法简单快速、准确可靠,测定结果相对标准偏差小于1%。

  5. Modification of HZSM- 5 Zeolite by Hydrochloric Acid and Catalytic Performance of Mo - based Catalyst for Methane Dehydroaromatization Reaction%盐酸改性HZSM-5及Mo-基催化剂的MDA反应活性

    Institute of Scientific and Technical Information of China (English)

    王红霞; 赵婷婷

    2012-01-01

    采用盐酸溶液在303K对HZSM-5分子筛进行预处理,并以处理后的分子筛制备相应的Mo-基催化剂.分子筛和催化剂采用XRD和NH3-TPD等手段进行表征,利用甲烷无氧芳构化(MDA)反应评价Mo-基催化剂的催化活性.结果表明,指定实验条件下的盐酸处理在一定程度上降低了分子筛的结晶度,降低了分子筛上的B酸量,改性后的Mo-基催化剂在MDA反应中表现很好的稳定性.%The pretreatment with HC1 solution at 303 K was applied to modify HZSM -5 zeolite, and the Mobased catalysts were prepared by using the modified HZSM -5 zeolite as support and tested for catalytic performance of methane dehydroaromatization reaction. The modified Mo - based catalysts show a higher stability than that of Mo/HZSM - 5 catalyst prepared with unmodified with HZSM - 5 zeolite. The effect of acid treatment on the structure and acidity of HZSM - 5 zeolite and Mo - based catalysts were studied by XRD and NH3 - TPD methods. The results show that the acid treatment to HZSM - 5 at given experimental conditions led to a decrease in the crystallinity of HZSM -5 zeolite and the number of the Brnsted acid sites to a certain degree.

  6. 盐酸介质磷钒钼黄直接光度法快速测定钒浸出液中的磷%Rapid phosphorus analysis in vanadium- leached solution using direct absorbance measurement in hydrochloric acid media phosphorus - vanadium - molybdenum yellow system

    Institute of Scientific and Technical Information of China (English)

    刘继宁; 马庆; 刘忠文; 党岚

    2001-01-01

    Compared with analytical characteristics and interfering factors for different media, hydrochloric acid was chosen as media in direct absorbance measurement to analyse phosphorus of Vanadium - leached solution.In this method, ammonium sodium was chosen as chromogenic agent, under the conditions that: the coloration acidity is 1.2 N, λ = 430 nm, ε = 1 300. We concluded that when phosphorus content is between 0 ~ 400 μg,Beer' s law is obeyed; when phosphorus content is lower limit 1.67 μg(3s), the coexistence components don' t interfere with phosphorus; when phosphorus content is 50 ~ 350 μg, the adding standard sample rate of recovery is 97.76% ~ 102. 1%; when phosphorus content is 100 μg, eleven times analyses are made and given. RSD =1.52% and X = 100. 48 μ-g.%研究了不同介质中钒钼黄法的分析特性和干扰因素,选定盐酸介质建立了快速分析钒浸出液中磷的直接光度法.该方法用钼酸钠作显色剂,显色酸度1.2 N,λ=430 nm,ε=1300,0~400μg线性良好;检测下限1.67μg(3s),共存组分无干扰,50~350μg加标回收率97.6%~102.1%,100μg中重复11次分析,RSD=1.52%,X=100.48μg.

  7. 盐酸液中钇(Ⅲ)和铕(Ⅲ)的P507溶剂萃取平衡分析%Equilibrium analysis of solvent extraction of yttrium(Ⅲ)and europium(Ⅲ)from hydrochloric acid with P507

    Institute of Scientific and Technical Information of China (English)

    付念新; 隋智通; Mikiya TANAKA

    2011-01-01

    为了精确预测非理想条件下稀土金属溶剂萃取的平衡分配比,研究了溶于Shellsol D70中的P507溶剂对盐酸液中钇(Ⅲ)和铕(Ⅲ)的萃取平衡,建立化学基模型,并通过非线性最小二乘法确定萃取平衡常数.所建模型涉及了在低酸度区的离子交换反应和高酸度区的溶剂化萃取反应;模型还考虑了稀土金属与Cl-的配位反应,并用萃取剂的有效浓度代替[(HR)2],进而分别对水相和有机相(HR2)的非理想性加以修正.对稀土单元体系,在较宽的初始浓度范围内(稀土浓度最高至0.1 mol/L,盐酸浓度0.07-3.00 mol/L,萃取剂浓度0.25-1.00 mol/L),由模型计算的稀土分配比与实验测得的数据吻合良好,验证了模型的有效性.对于稀土二元体系,该模型能以良好的精度对平衡分配比进行工程预测.%For the accurate prediction of equilibrium distribution ratios of rare earth metals during solvent extraction under non-ideal conditions,the extraction equilibria of yttrium(Ⅲ)and europium(Ⅲ)from the hydrochloric acid solutions with P507 in Shellsoi D70 were studied.A chemically-based model was established and the extraction equilibrium constants were determined by the nonlinear least squares method.The proposed model involves the cation exchange reaction and the solvation extraction in the low and high acidity regions,respectively.In the model,the nonideality of the aqueous phase and(HR)2 was corrected by considering the complexation of the metals with(Cl-)and by replacing[(HR)2]with its effective concentration,respectively.This model was verified by fair agreement between the calculated metal distribution ratios and those experimentally obtained in the single metal systems.The feed concentrations for the systems are in wide ranges of the metal(up to 0.1 mol/L),hydrochloric acid(0.07-3.00 mol/L)and the extractant(0.25-1.00 mol/L).The model enables the engineering prediction of the equilibrium distribution ratios with good

  8. Effect of Schiff base as corrosion inhibitor on AZ31 magnesium alloy in hydrochloric acid solution%席夫碱作为缓蚀剂对盐酸溶液中AZ31镁合金的影响

    Institute of Scientific and Technical Information of China (English)

    S. THIRUGNANASELVI; S. KUTTIRANI; Amali Roseline EMELDA

    2014-01-01

    Schiff base derived from the condensation reaction of analar grade 1-amino-2-naphthol 4-sulphonic acid with cinnamaldehyde was prepared under microwave condition. The Schiff base was analysed by infrared spectroscopy. This Schiff base as a corrosion inhibitor of AZ31 magnesium alloy in 0.05 mol/L HCl solution was studied. The inhibition effect of the Schiff base compound (4Z)-4-(3-phenyl allylidene amino)-3-hydroxy naphthalene-1-sulfonic acid (AC) on AZ31 magnesium alloy corrosion was studied using mass loss, potentiodynamic polarization technique, electrochemical impedance spectroscopy methods. The potentiodynamic polarization curve shows that Schiff base AC inhibits both anodic and cathodic reactions at all concentration, which indicates it is a mixed type inhibitor. EIS results indicate that as the additive concentration is increased, the polarization resistance increases whereas double-layer capacitance decreases. The adsorption of AC on the AZ31 magnesium alloy surface in 0.05 mol/L HCl obeys the Langmuir adsorption isotherm.%在微波条件下,通过高纯度1-氨基-2萘酚4-磺酸与肉桂醛的缩合反应制备席夫碱(4Z)-4-(3-苯基烯丙叉氨基)-3-羟基萘-1-磺酸(AC)。采用红外光谱对制备的席夫碱进行分析。研究席夫碱作为缓蚀剂对AZ31镁合金在0.05 mol/L 盐酸中的缓蚀作用。通过质量损失法、动电位极化法和电化学交流阻抗谱(EIS)研究席夫碱化合物在 AZ31镁合金腐蚀过程中的抑制作用。动电位极化曲线表明:席夫碱在所有浓度下能抑制阳极和阴极反应,是一种混合型缓蚀剂。EIS结果表明:随着添加剂浓度的增加,极化电阻增加而双电层电容减少。在0.05 mol/L盐酸中,席夫碱AC对AZ31镁合金表面的吸附符合Langmuir吸附等温式。

  9. 胺碘酮和普罗帕酮治疗阵发性室上性心动过速的疗效对照研究%Controlled study on effect of amiodarone and hydrochloric acid propafenone on paroxysmal supraventricular tachycardia

    Institute of Scientific and Technical Information of China (English)

    霍秋玉

    2012-01-01

    Objective To observe the clinical efficacy and safety of intravenous amiodarone and hydrochloric acid propafenone in treating paroxysmal supraventricular tachycardia. Methods Eighty patients with paroxysmal supraventricular tachycardia were divieded into group A and B randomly (40 cases in each group). Group A received amiodarone, while group B received hydrochloric acid propafenone. The effective rate of cardioversion, cardioversion time, adverse reactions and the heart rate change were compared. Results The effective rate in group A was higher than that in group B, but the difference was not statistically significant. The cardioversion time in group A was obviously longer than that in group B (P<0. 01). The heart rates in the two groups after treatment decreased obviously (P<0.01), while the heart rate in group A was obviously lower than that in group B (P<0. 01). The incidence of adverse reactions in group A was lower than that in group B, but the difference was not statistically significant. Conclusion There are advantages of both amiodarone and propafenone in the treatment of paroxysmal supraventricular tachycardia. Propafenone is applicable to acute tachycardia, but adverse reactions should be taken into consideration. The amiodarone is effective in the treatment of paroxysmal supraventricular tachycardia in spite of the slow onset.%目的 比较静脉注射胺碘酮和普罗帕酮治疗阵发性室上心动过速的临床疗效及安全性.方法 将80例室上心动过速患者随机分为A、B 2组,各40例,A组给予胺碘酮注射液治疗,B组给予普岁帕酮注射液治疗,比较2组复律成功率、复律时间、不良反应及用药前后心率的变化.结果 A组复律成功率高于B组,但差异无统计学意义(P>0.05),而复律时间显著长于B组(P<0.01);2组治疗后心率均较治疗前显著下降(P<0.01),但治疗后A组心率显著低于B组(P<0.01).A组不良反应发生率低于B组,但差异无统计学意义.结论

  10. 脂肪胺类化合物在盐酸介质中对工业纯铝缓蚀作用的研究%An investigation on the inhibition effect of aliphatic amines for aluminium in hydrochloric acid

    Institute of Scientific and Technical Information of China (English)

    帅长庚; 邓淑珍; 宋玉苏; 银继伟

    2001-01-01

    The corrosion of industrial pure aluminium in 1.0 mol.dm-3hydrochloride acid is investigated in the absence and presence of various amines,both by weight loss and electrochemistry.To begin with,the inhibition efficiency is found to follow the order: Hexamethylenetetramine>Diethylamine>n-Butylamine. With the increasing of the dipping time, the inhibition efficiency decreases gradually. The three amines, as the mixed inhibitors, has a great effect on the progress of cathodal and anodic corrosion of Al and can form a film by the adsorption on the surface of Al to protect Al from corrosion.%通过失重法、电化学方法分别研究了正丁胺、二乙胺、乌洛托品在1.0mol.dm-3HCl中对铝的缓蚀作用,并对其机理进行了探讨.研究结果表明:3种化合物对工业纯铝均具有一定的缓蚀作用.缓蚀效果:乌洛托品>二乙胺>正丁胺,随着时间的延长,它们的缓蚀效率逐渐降低.3种化合物均可在工业纯铝表面吸附成膜,抑制铝的腐蚀,为混合型缓蚀剂.

  11. Evaluation of Chromogenic Reaction Ability of Hydrochloric Acid (Sulfuric Acid)-vanillin by the Colorimetry for Determining Tea Catechins Aggregates%茶叶儿茶素总量比色测定的盐酸(硫酸)香草醛显色反应能力评价

    Institute of Scientific and Technical Information of China (English)

    单虹丽; 卿钰; 杜晓; 刘东娜

    2012-01-01

    Chromogenic reaction level of catechins from the green tea and the black tea with hydrochloric acid (sulfuric acid-vanillin)-vanillin was determined in this paper. By determining and comparing the reaction coefficient, accuracy and precision, the color reaction ability of catechins reacted with acid vanillin was evaluated. The results showed that the reaction system was sensitive to catechins with a high linear correlation(R2HA =0.9976 ±0.001 4, R2SA =0.9978 ±0.001 8). It was also seen that the chromogenic reaction coefficients from both systems were less than the Roberts coefficient (145.68) obtained from the empirical formula for calculating catechins aggregates. The recoveries from both system were more than 94.22 % and all the variation coefficient of precision were less than 0.08 %. This showed that both systems could determinate tea catechins aggregates. The chromogenic capability of tea catechins from different sources with acid-Vanillin was very different from each other (F = 37. 434 > F0.01(1,5) =6.61). This results showed that two kinds of reaction systems could objectively reflect tea catechins aggregates. However, both recoveries and variation coefficient from the empirical formula were instable and the total catechins aggregates was higher than the reality.%测定了茶叶儿茶素及绿茶、红茶中的儿茶素与盐酸(硫酸)-香草醛的显色反应水平,通过对反应系数、准确度、精密度测定和比较,评价了儿茶素与酸性香草醛的显色反应能力.结果表明:两种酸性体系对儿茶素反应灵敏,且呈高度线性相关(R2盐酸=0.9976±0.0014,R2硫酸=0.9978±0.0018);显色反应系数上,盐酸法为34.77±10.00(绿茶)、83.83±20.13(红茶);硫酸法为39.65±8.97(绿茶)、86.68±19.87(红茶),均低于茶叶儿茶素总量经验计算公式中Roberts系数(145.68).盐酸-香草醛显色反应体系的回收率为94.22%±3.33%(绿茶)、99.71%±1.39%(红茶),精密度的变异系数为0.08

  12. Effects of hydrochloric acid modification on the channel characteristics, composition, surface potential and cation exchange behavior of natural clinoptilolite%盐酸改性对天然斜发沸石孔道特征、成分、表面电位及阳离子交换性能的影响

    Institute of Scientific and Technical Information of China (English)

    霍汉鑫; 林海; 董颖博; 刘泉利; 曹丽霞; 程皝; 汪涵; 傅川

    2015-01-01

    采用不同浓度盐酸对天然斜发沸石进行改性,并系统地研究了改性沸石的孔道特征、化学成分、表面电位及阳离子交换性能的变化.盐酸改性后,沸石晶体结构破坏较小,表面变得疏松粗糙,K+、Na+、Ca2+和Mg2+元素含量均小幅下降;表面负电荷增加,阳离子交换容量减小;比表面积和总孔体积均有所提高,最高分别从原沸石的35.97 m2·g -1和0.0761 m3·g-1提高至64.46 m2·g-1和0.1156 m3·g-1.盐酸改性对沸石微孔、介孔和大孔的分布影响明显.从迟滞回线形状判断沸石孔道类型均为不均匀狭缝型孔道,盐酸改性不会改变沸石孔道类型.%ABSTRACT Natural clinoptilolite was modified by different concentrations of hydrochloric acid. Systemic investigations were performed on the channel characteristics, chemical composition, surface potential, and cation exchange behavior of the modified clinoptilolite. It is found that the surface of the modified clinoptilolite becomes loose and rough, the contents of K+, Na+, Ca2+, and Mg2+ slightly decrease, the surface negative charges increases, and the cation exchange capacity decreases to some extent. The specif-ic surface area and total pore volume are improved and the maximum values of them increase from 35.97 m2·g-1 and 0.0761 m3·g-1 to 64.46 m2·g-1 and 0.1156 m3·g-1 , respectively. The distribution of micropores, mesopores, and macropores is obviously impacted, and the type of zeolite cavities is determined to be uneven slits by the hysteresis loop shape, indicating that this acid modification cannot change zeolite cavities.

  13. On-line Determination of Hydrochloric Acid in Process Effluent ...

    African Journals Online (AJOL)

    Prof Van Staden

    The results obtained with the proposed system were compared with the results obtained from ..... The null hypothesis which assumes that the quantities from two different ... 14 R.H. Taylor, J. Ruzicka and G.D. Christian, Talanta, 1992, 39, 285.

  14. Determination of aluminum in aluminum electrolyte by EDTA back titration with ethanol-cuprous chloride-ammonium chloride-hydrochloric acid complex solvent separation%乙醇-氯化亚铜-氯化铵-盐酸复合溶剂分离-EDTA返滴定法测定铝电解质中单质铝

    Institute of Scientific and Technical Information of China (English)

    蒲秋梅; 任凤莲; 曹福悦

    2011-01-01

    新型低温铝电解质体系物相组成复杂,单质铝的分离测定尤为困难.本文采用高选择性复合溶剂乙醇-氯化亚铜-氯化铵-盐酸(ECAH)直接分离后测定铝电解质中单质铝,成功解决了单质铝与其它铝的化合物分离困难的问题,有效降低了铝电解质溶样时铝的氟化物的微溶效应带来的误差,为铝电解质中单质铝的物相分析提供了可靠的研究方案.采用经典ED-TA络合返滴定法测得铝电解质样品中单质铝含量,加标回收率在97%~103%之间,RSD(n=6)为1.1%和1.5%.测定结果和Al-CAS-OP-CPC四元络合光度法测定结果进行比对,结果一致.%It was particularly difficult to separate and determine aluminum in new low-temperature aluminum electrolyte system because of its complicated components. In this paper, aluminum in aluminum electrolyte was directly separated and determined using high-selectivity ethanol -cuprous chlorideammomum chloride-hydrochloric acid (ECAH) as complex solvent. This method successfully settled the problem of difficult separation of aluminum from aluminum compounds, effectively reduced the determination error introduced by slight soluble effect of fluoride of aluminum during the dissolution of aluminum electrolyte, and provided a reliable research method for the phase analysis of aluminum in aluminum electrolyte. Aluminum in aluminum electrolyte samples was determined by classic EDTA complexing back titration method. The standard addition recoveries were 97%-103 %, and the relative standard deviations (RSD, n=6) were 1. 1 % and 1. 5 %, respectively. The determination results were in good agreement with those obtained by Al-CAS-OP-CPC quaternary complex photometry.

  15. Quantification of Multi Elements in Geological Samples by Inductively Coupled Plasma-Mass Spectrometry with Pressurized Decomposition-Hydrochloric Acid Extraction%封闭压力酸溶-盐酸提取-电感耦合等离子体质谱法测定地质样品中的多元素

    Institute of Scientific and Technical Information of China (English)

    张保科; 温宏利; 王蕾; 马生凤; 巩爱华

    2011-01-01

    Rock, soil, sediments and other geological samples can be effectively decomposed by acid under high temperature and pressure, and be measured by Inductively Coupled Plasma-Mass Spectrometry ( ICP-MS ). The recoveries of most elements were satisfactory, except for the results of Zr, Hf, REEs, Rb, Th, and U. In this paper, the traditional pressurized acid digestion method has been improved as the sample was extracted by hydrochloric acid instead of nitric acid. 46 elements in the National Standard Materials of rock, soil and sediments can be accurately determined by this improved method. Sample weight was increased from 25 mg to 100m and digestion time was extended from 12 h to 48 h,which effectively resolved the problems including the representation of the samples and inadequate results for Rb, Sr, REEs and other elements dissolved by HN03. The results of many experiments showed that the 44 elements measured were consistent with standard values except for As and V elements, according to Cl interference in ICP-MS. Detection limits of the improved method were 0. 01 -0. 85 μg/g, with a precision RSD( n = 10 ) of 0. 73% -13. 1% and an accuracy RE( n = 10 )of less than 10%. The improved method is accurate, reliable and suitable for avariety of different types of geological samples.%高温、高压封闭压力酸溶可有效分解岩石、土壤、沉积物等地质样品,采用电感耦合等离子体质谱法(ICP-MS)进行测定,大部分元素可得到满意的回收率;但Zr、Hf、REEs、Rb、Th、U等元素用硝酸复溶困难,测定结果不准确.本文对传统的封闭压力酸溶方法进行改进,用盐酸复溶提取代替硝酸复溶提取,ICP-MS法测定岩石、土壤、沉积物等国家一级标准物质中Li、Be、Cr、Mn、Co、Ni、Cu、Zn、Ga、Rb、Sr、Mo、Cd、In、Cs、Ba、Ti、Zr、Nb、Sn、Sb、W、Hf、Ta、Tl、Pb、Bi、Th、U以及稀土元素(REEs)等46个元素.将原方法中的称样量25 mg加大至100 mg,溶样时间由12 h

  16. Expression of NGF in the respiratory tract mucosa of the repetitive oesphageal stimulation by hydrochloric acid in guinea pig%神经生长因子在多次盐酸灌注食管气道高反应豚鼠肺组织中的表达

    Institute of Scientific and Technical Information of China (English)

    李芹子; 孔灵菲; 张宝辉; 张姝娜; 孙淑华

    2010-01-01

    目的 观察多次盐酸灌注豚鼠食管对呼吸道黏膜内神经生长因子(nerve growth factor,NGF)物质表达的影响.方法 将20只豚鼠按随机数字表法分为2组,每组10只.①模型组:用盐酸氯胺酮将豚鼠轻度麻醉,将5F胃管插入豚鼠食管至食管中下端,灌注含0.5%胃蛋白酶的盐酸(0.1 mol/L,8滴/min,20 min/d),连续灌注14 d;②对照组:用PBS代替盐酸灌注食管,方法同上.用免疫组织化学方法测定两组豚鼠肺组织NGF的免疫反应变化;用免疫印迹法(Western blotting)检测肺组织NGF的免疫反应变化;Metamoph图像分析系统对结果进行分析.结果 免疫组织化学结果显示(染色反应强度用灰度值表示):模型组豚鼠气管和细支气管黏膜内NGF物质阳性反应的平均灰度值明显地低于对照组[(108.46±9.89)vs(135.86±4.01)](P<0.01).Western blotting显示NGF在模型组豚鼠的肺内平均相对光密度值明显强于对照组[(1.415±0.155)vs(0.550±0.039)](P<0.01).结论 多次盐酸灌注豚鼠食管后呼吸道黏膜内NGF物质表达明显增多,提示NGF可能参与胃食管反流性呼吸系统疾病的发病过程.%Objective To observe the expression of nerve growth factor(NGF)in respiratory tract mueosa of the repetitive esophageal stimulation by hydrochloric acid(HCl)in guinea pigs.Methods Twenty adult guinea pigs were randomly divided into two groups(n=10):①HCl model group:On the day of experimentation,guinea pigs were maintained under ketamine anesthesia.A 5F catheter was inserted through the mouth and into the lumen of the middle and lower oesophagus.The oesophagus of each animal was perfused with HCl-P for 20 min/d for 14 d.②PBS control group:The oesophagus of each animal was perfused with PBS.The alterations of NGF immunoreactivity were investigated by immunohistochemical and Western blotting method and analyzed by the Metamoph analysisi system.Results Immunohistochemistry demonstrated that the mean grey values of NGF positive

  17. Preparation, spectroscopic and acidity properties of two hydrazones: an organic lab experiment

    Energy Technology Data Exchange (ETDEWEB)

    Rezende, Marcos Caroli; Pizarro, Claudia; Millan, Daniela [Universidad de Santiago, Santiago (Chile). Facultad de Quimica y Biologia]. E-mail: mcaroli@lauca.usach.cl

    2007-01-15

    An undergraduate organic lab experiment is described based on the preparation of two readily accessible hydrazones. The UVvisible spectra of these N-H acids and of their conjugate bases are employed to illustrate the importance of through-conjugation in determining their acid strength and their internal charge-transfer-band transitions. (auth0008.

  18. Recovery of Pd(II) from hydrochloric solution using polyallylamine hydrochloride-modified Escherichia coli biomass.

    Science.gov (United States)

    Park, Jiyeong; Won, Sung Wook; Mao, Juan; Kwak, In Seob; Yun, Yeoung-Sang

    2010-09-15

    A new type of biosorbent able to bind anionic metals was developed by cross-linking of waste biomass Escherichia coli with polyallylamine hydrochloride (PAH). The PAH-modified biomass was investigated for the removal and recovery of Pd(II), in the chloro-complex form, from aqueous solution. The performance of the PAH-modified biomass was evaluated in terms of the following parameters: the solution pH, contact time and initial metal concentration. In the pH edge experiments, the uptake of Pd(II) increased with increasing pH. Pd(II) biosorption proceeded rapidly in the first 10 min, with almost complete equilibrium being achieved within 60 min. Moreover, the isotherm data showed that the maximum uptakes of Pd(II) were 265.3mg/g at pH 3 and 212.9 mg/g at pH 2, respectively. After incineration of the Pd-loaded PAH-modified biomass, metallic palladium was recovered in the ash. X-ray photoelectron spectroscopy (XPS) results confirmed that the palladium was recovered in two valency states: zero-valent and divalent palladium (as PdO). Therefore, we concluded that PAH-modified biomass is a useful and cost-effective biosorbent for the recovery of anionic precious metals as chloro-complex solutions containing hydrochloric acid produced from metal refining processes.

  19. 49 CFR 173.158 - Nitric acid.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Nitric acid. 173.158 Section 173.158... Nitric acid. (a) Nitric acid exceeding 40 percent concentration may not be packaged with any other material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid as...

  20. DILUTE SOLUTION BEHAVIOR OF CHITOSAN IN DIFFERENT ACID SOLVENTS

    Institute of Scientific and Technical Information of China (English)

    WANG Wei; WANG Lihua; QIN Wen

    1994-01-01

    Dilute solution behavior of chitosan was studied in formic acid, acetic acid,lactic acid and hydrochloric acid aqueous solution under different pH values. The reduced viscosities, ηsp/C,of chitosan solutions were dependent on the properties of acid and pH value of solvents. For a given chitosan concentration, ηsp/C decreased with the increase of acid concentration, or decreasing pH of solvent, indicating shielding effect of excessive acid similar to adding salt into solution. The stabilities of dilute chitosan solution in formic acid and lactic acid were better than that in acetic acid and hydrochloric acid.

  1. Application of hydrochloric cyclopentolate eye drops in the mydriasis test and optometry for children with hyperopia

    Directory of Open Access Journals (Sweden)

    Hong-Ping Yin

    2016-02-01

    Full Text Available AIM:To observe and study the comprehensive application effect of hydrochloric cyclopentolate eye drops in the mydriasis test and optometry for children with hyperopia.METHODS:Eighty-four children with hyperopia who were intervened with mydriasis test and optometry in our hospital from February 2014 to March 2015 were selected as the research object,and they were intervened with mydriasis test and optometry by tropicamide or hydrochloric cyclopentolate eye drops. The diopter, pupil diameter and residual regulation before administration and at different time after administration of the two methods were compared,and the detected results of the two groups with different severity degree were compared too.RESULTS:The diopter, pupil diameter and residual regulation before administration of the two eye drops had no significant differences(all P>0.05,while the residual regulation after using hydrochloric cyclopentolate eye drops at 20, 40, 60min and 24h were all smaller than those after using tropicamide(all PP>0.05. The pupil diameter of the two groups at 48h after administration both had no significant differences to those before administration(all P>0.05.CONCLUSION:The comprehensive application effect of hydrochloric cyclopentolate eye drops in the mydriasis test and optometry of children with hyperopia is better,and its paralysis effect for ciliaris is obvious.

  2. Ab initio investigations of the dynamic and thermodynamic properties of atmospherically relevant strong acids

    OpenAIRE

    Partanen, Lauri

    2017-01-01

    Sulfuric and hydrochloric acids participate in several important chemical processes occurring in the atmosphere. Due to its tendency to react with water molecules, sulfuric acid is an important factor in cloud formation and related phenomena. Hydrochloric acid is heavily implicated in stratospheric ozone depletion because of its role as a temporary reservoir for chlorine radicals. In this thesis, the thermodynamics and dynamics of these two acids are investigated. The dynamic part focuse...

  3. Hafnium extraction from acidic chloride solutions by Cyanex 923

    Energy Technology Data Exchange (ETDEWEB)

    El-Ammouri, E.; Distin, P.A. [McGill Univ., Montreal (Canada)

    1996-08-01

    Hafnium extraction from hydrochloric acid/lithium chloride solutions into Cyanex 923 in kerosene has been studied. Variables investigated were hydrochloric acid, total chloride and hafnium concentrations in the aqueous phase, and extractant/modifier (isodecanol) levels in the organic phase. Hafnium is considered to load as the tetrachloride complex forming a disolvate with Cyanex 923. Results are compared with equivalent data for zirconium extraction. 14 refs., 7 figs., 2 tabs.

  4. Corrosão de cerâmicas à base de Si3N4 em soluções aquosas de HCl 0,1 N Corrosion of Si3N4 ceramics in 0.1 N hydrochloric acid solution

    Directory of Open Access Journals (Sweden)

    F. Vernilli Júnior

    1999-06-01

    Full Text Available O comportamento à corrosão de cerâmicas à base de Si3N4 contendo misturas de Y2O3/SiO2 e RE2O3/SiO2 como aditivos nas proporções de 14 e 21% em volume ambos na estequiometria dos dissilicatos Y2Si2O7 e RE2Si2O7, respectivamente, foi estudado em soluções aquosas de HCl 0,1N a 100 °C. A resistência à corrosão foi avaliada pela perda de massa das amostras e análise química das soluções após os testes. As análises por microscopia eletrônica das amostras atacadas revelou que basicamemte a fase vítrea intergranular foi dissolvida pela solução ácida, deixando um esqueleto de grãos de b-Si3N4 entrelaçados.The corrosion resistance of Si3N4 ceramics with 14 and 21 vol.% of Y2O3/SiO2 and RE2O3/SiO2 mixtures as additive, both in the stoichiometry of disilicates Y2 Si2O7 and RE2Si2O7, respectively, has been investigated in 0.1N HCl solutions. Samples were prepared by a two step gas pressure sintering process, under a final N2 pressure of 10 MPa and a maximum temperature of 1850 °C for 30 min. The corrosion resistance was evaluated by the mass change of polished samples and chemical analysis of the solutions after the tests. Analysis by electron microscopy showed that the glassy intergranular phase is dissolved by the acid solution, leaving a skeleton of interlinked b -Si3N4 grains.

  5. 46 CFR 151.50-76 - Hydrochloric acid, spent (NTE 15%).

    Science.gov (United States)

    2010-10-01

    ... two fitted flame screens as described in § 151.03-25. Neither a shut-off valve nor a frangible disk... gaskets. (c) Where special arrangements are approved by the Commandant (CG-522) to permit a pump...

  6. 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.

  7. Inhibition of Mild Steel Corrosion in Hydrochloric Acid Solution by New Coumarin

    Directory of Open Access Journals (Sweden)

    Abdul Amir H. Kadhum

    2014-06-01

    Full Text Available A new coumarin derivative, N,N′-((2E,2′E-2,2′-(1,4-phenylenebis (methanylylidenebis(hydrazinecarbonothioylbis(2-oxo-2H-chromene-3-carboxamide PMBH, was synthesized and its chemical structure was elucidated and confirmed using spectroscopic techniques (Infrared spectroscopy IR, Proton nuclear  magnetic resonance, 1H-NMR and carbon-13 nuclear magnetic resonance 13C-NMR. The corrosion inhibition effect of PMBH on mild steel in 1.0 M HCl was investigated using corrosion potential (ECORR, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS, and electrochemical frequency modulation (EFM measurements. The obtained results indicated that PMBH has promising inhibitive effects on the corrosion of mild steel in 1.0 M HCl across all of the conditions examined. Scanning electron microscopy (SEM was used to investigate the morphology of the mild steel before and after immersion in 1.0 M HCl solution containing 0.5 mM of PMBH. Surface analysis revealed improvement of corrosion resistance in presence of PMBH.

  8. Punica granatum leave extract as green corrosion inhibitor for mild steel in Hydrochloric acid

    OpenAIRE

    Abboud Y.; Chagraoui A.; Tanane O.; El Bouari A.; Hannache H.

    2013-01-01

    Leave of Punica granatum extract (LPGE) as green inhibitor for the corrosion of mild steel in 1M HCl solution was studied using weight-loss and potentiodynamic polarization measurements. The results obtained revealed that LPGE has fairly good inhibiting properties for mild steel corrosion in 1M HCl solution, with efficiency of around 94 % at a concentration of 1 g/l. The inhibition was of a mixed anodic–cathodic nature. The film which is formed over the metal surface was analysed by FT-IR spe...

  9. Inhibition of copper corrosion in aerated hydrochloric acid solution by heterocyclic compounds containing a mercapto group

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Daquan; Gao Lixin; Zhou Guoding

    2004-12-01

    Inhibition of copper corrosion by benzotriazole (BTA), 2-mercapto benzoxazole (MBO) and 2-mercapto benzimidazole (MBI) in 0.5 mol L{sup -1} HCl was investigated by weight-loss measurements, potentiodynamic polarization curves and electrochemical impedance spectroscopy. MBI was shown to be the most effective inhibitor among those tested. Potentiodynamic polarization results revealed that the three compounds acted as anodic inhibitors, particularly MBI strongly suppressed anodic current densities. Molecular structure parameters of BTA, MBO and MBI were obtained by using an MM2 forcefield program and PPP-SCF quantum chemical calculation. It was found that MBI has higher levels of HOMO and LUMO energy and the larger {pi}-electron density.

  10. Simultaneous Recovery of Hydrogen and Chlorine from Industrial Waste Dilute Hydrochloric Acid

    Directory of Open Access Journals (Sweden)

    N. Paidimarri

    2016-01-01

    Full Text Available Recovery of chlorine from byproduct HCl has inevitable commercial importance in industries lately because of insufficient purity or too low concentration to recycle it. Instead it is being neutralized in industries before disposing to meet stringent environmental conditions. Although recovery through catalytic oxidation processes is studied since the 19th century, their high operating conditions combined with sluggish reaction kinetics and low single pass conversions make electrolysis a better alternative. The present motive of this work is to develop a novel electrolysis process which in contrast to traditional processes effectively recovers both hydrogen and chlorine from dilute HCl. For this, an electrolytic cell with an Anionic Exchange Membrane has been designed which only allows the passage of chlorine anions from catholyte to anolyte separating the gasses in a single step. The catholyte can be as low as 3.59 wt% because of fixed anolyte concentration of 1.99 wt% which minimizes oxygen formation. Preliminary results show that the simultaneous recovery of hydrogen and chlorine is possible with high conversion up to 98%. The maximum current density value for 4.96 cm2 membrane surface area (70% active surface area is 2.54 kAm−2, which is comparable with reported commercial processes. This study is expected to be useful for process intensification of the same in a continuous process environment.

  11. The reduction of l-cystine in hydrochloric acid at mercury drop electrodes

    OpenAIRE

    Ralph, T.R.; Hitchman, M.L.; Millington, J.P.; Walsh, F.C.

    2006-01-01

    The reduction of L-cystine in 0.1 mol dm3 HCl at 298 K has been studied at mercury electrodes. Dropping mercury electrode (DME), static mercury drop electrode (SMDE) and hanging mercury drop electrode (HMDE) modes were used with normal, sampled d.c. and differential pulse polarographic detection. The charge transfer kinetics for the irreversible reduction of L-cystine were complicated by reactant and product adsorption, by the formation of cysteinate complexes between mercury and the product ...

  12. Kinetics of Rare Earth Extraction from Baotou Bastnaesite in Hydrochloric Acid and Aluminum Chloride

    Science.gov (United States)

    Zhang, Xiao-Wei; Li, Mei; Liu, Zhao-Gang; Hu, Yan-Hong; Wang, Mi-Tang

    2017-06-01

    In this paper, the leaching kinetics of rare earth from Baotou bastnaesite in a HCl-AlCl3 solution was investigated. In addition, the effects of the HCl and AlCl3 concentrations, liquid to solid ratio, stirring speed, temperature, and time spent on the rare earth extraction were determined. The results indicated that the extraction was nearly independent of the stirring speed when it did not exceed 300 rpm, and the rate of leaching increased with increases in the HCl and AlCl3 concentrations, liquid to solid ratio, temperature, and time. The optimum dissolution conditions were determined under five experimental conditions. After leaching occurred, the progressive dissolution of the bastnaesite phase could be determined. The leaching kinetics was analyzed with a new variant of the shrinking core model in which both the interfacial transfer and diffusion across the product layer affected the rare earth extraction. The apparent activation energy was 35.57 kJ/mol, and the Arrhenius constant was 341.58 min-1. An empirical equation was derived to describe the extraction process of rare earth minerals.

  13. Electrochemical Study on Newly Synthesized Chlorocurcumin as an Inhibitor for Mild Steel Corrosion in Hydrochloric Acid

    Directory of Open Access Journals (Sweden)

    Ahmed A. Al-Amiery

    2013-11-01

    Full Text Available A new curcumin derivative, i.e., (1E,4Z,6E-5-chloro-1,7-bis(4-hydroxy-3-methoxyphenylhepta-1,4,6-trien-3-one (chlorocurcumin, was prepared starting with the natural compound curcumin. The newly synthesized compound was characterized by elemental analysis and spectral studies (IR, 1H-NMR and 13C-NMR. The corrosion inhibition of mild steel in 1 M HCl by chlorocurcumin has been studied using potentiodynamic polarization (PDP measurements and electrochemical impedance spectroscopy (EIS. The inhibition efficiency increases with the concentration of the inhibitor but decreases with increases in temperature. The potentiodynamic polarization reveals that chlorocurcumin is a mixed-type inhibitor. The kinetic parameters for mild steel corrosion were determined and discussed.

  14. A new online exhaust gas monitoring system in hydrochloric acid regeneration of cold rolling mills.

    Science.gov (United States)

    Tuo, Long; Zheng, Xiang; Chen, Xiong

    2015-07-07

    Measuring the content of hydrogen chloride (HCl) in exhaust gas used to take time and energy. In this paper, we introduce a new online monitoring system which can output real-time data to the monitoring center. The system samples and cools exhaust gas, and after a series of processing, it will be analyzed by a specific instrument. The core part of this system is remote terminal unit (RTU) which is designed on Cortex-A8 embedded architecture. RTU runs a scaled-down version of Linux which is a good choice of OS for embedded applications. It controls the whole processes, does data acquisition and data analysis, and communicates with monitoring center through Ethernet. In addition, through a software developed for windows, the monitoring process can be remotely controlled. The new system is quite beneficial for steel industry to do environment monitoring.

  15. Corrosion Behavior of Ni3(Si,Ti in Hydrochloric Acid Solution

    Directory of Open Access Journals (Sweden)

    Gadang Priyotomo

    2013-06-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} The corrosion behaviour of the intermetallic compounds Ni3(Si,Ti (L12: single phase, has been investigated using an immersion test, electrochemical method, scanning electron microscope in 0.5 kmol/m3 HCl at 303 K. In addition, the corrosion behaviour of austenitic stainless steel type 304 and C276 was studied under the same experimental conditions as references. It was found that the intergranular attack was observed for Ni3(Si,Ti in the immersion test. From the immersion test and polarization curves, Ni3(Si,Ti had the moderate corrosion resistance, while the corrosion resistances of C 276 and type 304 were the highest and the lowest. Ni3(Si,Ti and type 304 were difficult to form a stable passive film, but not for C276. A further experiment must be conducted to clarify the stability of film for Ni3(Si,Ti in detail.

  16. Corrosion inhibition of mild steel in hydrochloric acid solution by some double Schiff bases

    Energy Technology Data Exchange (ETDEWEB)

    Soltani, N. [Payame Noor University (PNU), Shahin Shahr Branch, Isfahan (Iran, Islamic Republic of)], E-mail: N.Soltani@kashanu.ac.ir; Behpour, M.; Ghoreishi, S.M.; Naeimi, H. [Department of Chemistry, Faculty of Science, University of Kashan, Kashan (Iran, Islamic Republic of)

    2010-04-15

    The inhibition effect of four double Schiff bases on the corrosion of mild steel in 2 M HCl has been studied by polarization, electrochemical impedance spectroscopy (EIS) and weight loss measurements. The inhibitors were adsorbed on the steel surface according to the Langmuir adsorption isotherm model. From the adsorption isotherm, some thermodynamic data for the adsorption process were calculated and discussed. Kinetic parameters activation such as E{sub a}, {delta}H*, {delta}S* were evaluated from the effect of temperature on corrosion and inhibition processes. Quantum chemical calculations have been performed and several quantum chemical indices were calculated and correlated with the corresponding inhibition efficiencies.

  17. Interactions of some Schiff base compounds with mild steel surface in hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Bayol, Emel [Department of Chemistry, Faculty of Science and Art, Nigde University, Nigde 51200 (Turkey); Guerten, Tijen [Department of Chemistry, Faculty of Science and Art, Cukurova University, Adana 01330 (Turkey); Guerten, A. Ali [Department of Chemistry, Faculty of Science and Art, Nigde University, Nigde 51200 (Turkey)], E-mail: agurten@nigde.edu.tr; Erbil, Mehmet [Department of Chemistry, Faculty of Science and Art, Cukurova University, Adana 01330 (Turkey)

    2008-12-01

    The inhibition effect of the Schiff bases N,N'-bis(salicylidene)-1,2-ethylenediamine (Salen), N,N'-bis(5-methoxysalicylidene)-1,2-ethylenediamine (MeO-Salen) and N,N'-bis(5-nitrosalicylidene)-1,2-ethylenediamine (NO{sub 2}-Salen) on the corrosion of the mild steel in 1.0 M HCl has been studied by electrochemical impedance spectroscopy (EIS), linear polarisation resistance (LPR) and Tafel polarisation measurements. Maximum inhibition for MeO-Salen was obtained. Results showed that the inhibition efficiency have increased when the concentration of the Schiff bases have increased. Polarisation curves revealed that the Schiff bases acted as anodic inhibitors. The surface adsorption of the Schiff bases has lead to a decrease in the double layer capacitance and to an increase in polarisation resistance. The inhibitor performance depended strongly on the type of functional groups on benzene ring. The adsorption process is spontaneous one and follows Langmuir adsorption isotherm model. Scanning electron microscopy (SEM) has been applied to identify the surface morphology of the mild steel both in the absence and presence of the Schiff base molecules.

  18. Performance of Different Acids on Sandstone Formations

    Directory of Open Access Journals (Sweden)

    M. A. Zaman

    2013-12-01

    Full Text Available Stimulation of sandstone formations is a challenging task, which involves several chemicals and physical interactions of the acid with the formation. Some of these reactions may result in formation damage. Mud acid has been successfully used to stimulate sandstone reservoirs for a number of years. It is a mixture of hydrofluoric (HF and hydrochloric (HCl acids designed to dissolve clays and siliceous fines accumulated in the near-wellbore region. Matrix acidizing may also be used to increase formation permeability in undamaged wells. The change may be up to 50% to 100% with the mud acid. For any acidizing process, the selection of acid (Formulation and Concentration and the design (Pre-flush, Main Acid, After-flush is very important. Different researchers are using different combinations of acids with different concentrations to get the best results for acidization. Mainly the common practice is combination of Hydrochloric Acid – Hydrofluoric with Concentration (3% HF – 12% HCl. This paper presents the results of a laboratory investigation of Orthophosphoric acid instead of hydrochloric acid in one combination and the second combination is Fluoboric and formic acid and the third one is formic and hydrofluoric acid. The results are compared with the mud acid and the results calculated are porosity, permeability, and FESEM Analysis and Strength tests. All of these new combinations shows that these have the potential to be used as acidizing acids on sandstone formations.

  19. High School Forum: "Invitations to Enquiry": The Calcite/Acid Reaction.

    Science.gov (United States)

    Herron, J. Dudley, Ed.; Driscoll, D. R.

    1979-01-01

    Describes a high school chemistry experiment which involves the reaction between calcite and hydrochloric and sulfuric acids. This reaction can be carried out as a projected demonstration and on an individual basis. (HM)

  20. New Acid Combination for a Successful Sandstone Acidizing

    Science.gov (United States)

    Shafiq, M. U.; Mahmud, H. K. B.; Rezaee, R.

    2017-05-01

    With the development of new enhanced oil recovery techniques, sandstone acidizing has been introduced and played a pivotal role in the petroleum industry. Different acid combinations have been applied, which react with the formation, dissolve the soluble particles; thus increase the production of hydrocarbons. To solve the problems which occurred using current preflush sandstone acidizing technology (hydrochloric acid); a new acid combination has been developed. Core flooding experiments on sandstone core samples with dimensions 1.5 in. × 3 in. were conducted at a flow rate of 2 cm3/min. A series of hydrochloric-acetic acid mixtures with different ratios were tested under 150°F temperature. The core flooding experiments performed are aimed to dissolve carbonate, sodium, potassium and calcium particles from the core samples. These experiments are followed by few important tests which include, porosity-permeability, pH value, Inductively Coupled Plasma (ICP) analysis and Nuclear Magnetic Resonance (NMR measurements). All the results are compared with the results of conventional hydrochloric acid technology. NMR and porosity analysis concluded that the new acid combination is more effective in creating fresh pore spaces and thus increasing the reservoir permeability. It can be seen from the pore distribution before and after the acidizing. Prior applying acid; the large size of pores appears most frequently in the pore distribution while with the applied acid, it was found that the small pore size is most the predominant of the pore distribution. These results are validated using ICP analysis which shows the effective removal of calcium and other positive ions from the core sample. This study concludes that the combination of acetic-hydrochloric acid can be a potential candidate for the preflush stage of sandstone acidizing at high temperature reservoirs.

  1. Acid-base strengths in pyridine

    NARCIS (Netherlands)

    Bos, M.; Dahmen, E.A.M.F.

    1971-01-01

    Although pyridine is a solvent with a low dielectric constant, spectrophotometric determinations show simple dissociation without ion pairs as intermediates for some sulfonphthaleins and polynitrophenols in pyridine. The salts of a number of amines and hydrochloric acid, perchloric acid and picric

  2. Facile synthesis of improved room temperature gas sensing properties of TiO2 nanostructures: Effect of acid treatment

    CSIR Research Space (South Africa)

    Tshabalala, Zamaswazi P

    2016-03-01

    Full Text Available TiO2 nanoparticles were synthesized via a simple hydrothermal method in a sodium hydroxide (NaOH) aqueous solution and washed with distilled water and different concentrations of hydrochloric acid which acted as the morphological...

  3. Performance Comparison of New Combinations of Acids with Mud Acid in Sandstone Acidizing

    Directory of Open Access Journals (Sweden)

    Mian Umer Shafiq

    2014-01-01

    Full Text Available The aim of this research is to find the best suitable acid to acidize undamaged low permeable sandstone formation Stimulation of sandstone formations is a challenging task, which involves several chemicals and physical interactions of the acid with the formation. Mud acid has been successfully used to stimulate sandstone reservoirs for a number of years. Matrix acidizing may also be used to increase formation permeability in undamaged wells. The change may be up to 50 to 100% with the mud acid. For any acidizing process, the selection of acid (Formulation and Concentration and the design (Pre-flush, Main Acid, After-flush is very important. Different researchers are using different combinations of acids with different concentrations to get the best results for acidization. Mainly the common practice is combination of Hydrochloric Acid- Hydrofluoric with Concentration (3% HF-12% HCl. This study presents the results of a laboratory investigation of Orthophosphoric acid instead of hydrochloric acid in one combination and the second combination is Fluoboric and formic acid and the third one is formic and hydrofluoric acid. The results are compared with the mud acid and the results analyzed are porosity, permeability, strength, color change and FESEM Analysis. All of these new combinations shows that these have the potential to be used as acidizing acids on sandstone formations.

  4. Influence of the use of acids and films in post-harvest lychee conservation

    Directory of Open Access Journals (Sweden)

    Danielle Fabíola Pereira da Silva

    2012-12-01

    Full Text Available Lychee (Litchi chinensis Sonn. has a high commercial value; however, it has a short shelf-life because of its rapid pericarp browning. The objective of this study was to evaluate the shelf-life of 'Bengal' lychee fruits stored after treatment with hydrochloric acid and citric acid, associated with cassava starch and plastic packaging. Uniformly red pericarp fruits were submitted to treatments: 1-(immersion in citric acid 100 mM for 5 minutes + cassava starch 30 g L-1 for 5 minutes, 2-(immersion in hydrochloric acid 1 M for 2 minutes + starch cassava 30 g L-1 for 5 minutes, 3-(immersion in citric acid 100 mM for 5 minutes + polyvinyl chloride film (PVC, 14 µm thick and 4-(immersion in hydrochloric acid 1 M for 2 minutes + PVC film. During 20 days, the fruits were evaluated for mass loss, pericarp color, pH, soluble solids and titratable acidity, vitamin C of the pulp and pericarp and activities of polyphenol oxidase and peroxidase of the pericarp. The treatment with hydrochloric acid associated with PVC was the most effective in maintaining the red color of the pericarp for a period of 20 days and best preservation of the fruit. The cassava starch associated with citric acid, and hydrochloric acid did not reduce the mass loss and did not prevent the browning of lychee fruit pericarp.

  5. Role of membrane-bound enzymes in an early response of aleurone tissue to gibberellic acid

    Energy Technology Data Exchange (ETDEWEB)

    Varner, J.E. (Washington Univ., St. Louis); Ben-Tal, Y.

    Treatment of aleurone layers of barley seed with gibberellic acid increases the observable phosphorylcholine glyceride transferase activity in a membrane fraction prepared from extracts of the aleurone cells. This gibberellic acid-dependent increase in glyceride transferase activity requires neither RNA synthesis nor protein synthesis. Membrane fractions prepared from mixtures of extracts of gibberellic acid-treated layers and control layers have a specific activity of glyceride transferase higher than expected on the basis of simple addition of the activities from the two sources. Therefore, some kind of activation is occurring. (auth)

  6. Isolation of living Algae growing in the shells of Molluscs and Barnacles with EDTA (ethylenediaminetetraacetic acid)

    NARCIS (Netherlands)

    Prud’homme van Reine, W.F.; Hoek, van den C.

    1966-01-01

    Several decalcifying mixtures or aqueous solutions of inorganic or organic acids are generally used for releasing algae growing in the shells of molluscs and barnacles, for instance dilute hydrochloric, nitric, citric, or acetic acid (4), a mixture of nitric acid, chromic acid and alcolhol (1), nitr

  7. Isolation of living Algae growing in the shells of Molluscs and Barnacles with EDTA (ethylenediaminetetraacetic acid)

    NARCIS (Netherlands)

    Prud’homme van Reine, W.F.; Hoek, van den C.

    1966-01-01

    Several decalcifying mixtures or aqueous solutions of inorganic or organic acids are generally used for releasing algae growing in the shells of molluscs and barnacles, for instance dilute hydrochloric, nitric, citric, or acetic acid (4), a mixture of nitric acid, chromic acid and alcolhol (1),

  8. A Comparative Study on Corrosion Inhibition of Mild Steel Using Piper Nigrum L. in Different Acid Medium

    Directory of Open Access Journals (Sweden)

    B. Anand

    2010-01-01

    Full Text Available The inhibition of corrosion of mild steel using Piper nigrum L in different acid medium by weight loss method was investigated. The corrosion inhibition was studied in hydrochloric acid and sulphuric acid by weight loss method at different time interval at room temperature. The result showed that the corrosion inhibition efficiency of this compound was found to vary with different time interval and different acid concentration. Also, it was found that the corrosion inhibition behavior of Piper nigrum L is greater in sulphuric acid than hydrochloric acid. So, Piper nigrum L can be used as a good inhibitor for preventing mild steel material.

  9. Dissolving Carboxylic Acids and Primary Amines on the Overhead Projector

    Science.gov (United States)

    Solomon, Sally D.; Rutkowsky, Susan A.

    2010-01-01

    Liquid carboxylic acids (or primary amines) with limited solubility in water are dissolved by addition of aqueous sodium hydroxide (or hydrochloric acid) on the stage of an overhead projector using simple glassware and very small quantities of chemicals. This effective and colorful demonstration can be used to accompany discussions of the…

  10. KINETICS OF DISSOLUTION OF PHOSPHORITE IN ACID MIXTURES

    African Journals Online (AJOL)

    The effect of hydrochloric acid on the dissolution of fluorapatite by sulphuric acid was studied at various H2SO_,_:HCl volume ratios ranging from 100 to 0 volume % of the ... Indeed only diffusion controlled processes are affected by the stirring speed [27]. ... surface area of the dissolving mineral [30], in this case fluorapatite.

  11. Ion exchange equilibria in simultaneous extraction of platinum(II, IV) and rhodium(III) from hydrochloric solutions

    Science.gov (United States)

    Mel'nikov, A. M.; Kononova, O. N.; Pavlenko, N. I.; Krylov, A. S.

    2012-06-01

    Regularities of sorption extraction of platinum(II, IV) and rhodium(III) by anion exchangers of various physical and chemical structure in the presence of hydrochloric media were studied. It is established that AM-2B, Purolite A 500, and Purolite S 985 ionites adsorb complex anions of platinum metals employing mixed mechanism. A high affinity of the studied anionites for the studied complex anions of platinum and rhodium is established.

  12. Reactivity of clay minerals with acids and alkalies

    Science.gov (United States)

    Carroll, D.; Starkey, H.C.

    1971-01-01

    One-g samples of a montmorillonite, a metabentonite, an illite, two kaolinites, and three halloysites were treated with 50 ml of hydrochloric acid (6??45 N, 1:1), acetic acid (4??5 N, 1:3), sodium hydroxide (2??8 N), sodium chloride solution (pH 6??10; Na = 35???; Cl = 21??5???), and natural sea water (pH 7??85; Na = 35??5???; Cl = 21??5???) for a 10-day period in stoppered plastic vials. The supernatant solutions were removed from the clay minerals and analyzed for SiO2, Al2O3, CaO, MgO, Na2O, and K2O. All the solutions removed some SiO2, Al2O3, and Fe2O3 from the samples, but the quantities were small. Sodium hydroxide attacked the kaolin group minerals more strongly than it did montmorillonite, metabentonite, or illite. Halloysite was more strongly attacked by hydrochloric acid than was any of the other experimental minerals. Hydrochloric acid removed iron oxide coatings from soil clay minerals, but acetic acid did not remove them completely. The samples most strongly attacked by HCl and NaOH were examined by X-ray diffraction. Acid treatment did not destroy the structure of the clays, but the halloysite structure was partially destroyed. Sodium hydroxide attacked the halloysite structure, as shown by chemical analysis and X-ray diffraction. These experiments show that treatment in dilute acids has no harmful effect in the preparation of clays for X-ray diffraction. Acetic acid is preferred to hydrochloric acid for this purpose. Hydrochloric acid cleans clay minerals by removing free iron oxide from the surface; acetic acid is less effective. ?? 1971.

  13. Capsella bursa-pastoris extract as an eco-friendly inhibitor on the corrosion of Q235 carbon steels in 1 mol·L-1 hydrochloric acid☆

    Institute of Scientific and Technical Information of China (English)

    Qin Hu; Yubing Qiu; Guoan Zhang; Xingpeng Guo

    2015-01-01

    The corrosion inhibition effect of Capsel a bursa-pastoris extracts (CBE) for Q235 carbon steels in 1 mol·L−1 hy-drochloric acid solution was studied using electrochemical methods, environmental scanning electron microsco-py (SEM) and Raman microscopy analysis. The polarization plots indicate that CBE serves as an effective, mixed-type inhibitor. Linear polarization resistance shows that increasing CBE concentration and temperature results in increased inhibition efficiency. The highest inhibition efficiency can reach 97%when adding 60 mg·L−1 CBE, which is better than some reported plant extracts under the similar environment. The adsorption of CBE molecules is found to obey the Langmuir adsorption isotherm. Some thermodynamic and kinetic parameters for the adsorption process, such as the adsorption equilibrium constant (K), free energy of adsorption (ΔGads), ac-tivation energy of corrosion reaction (Ea) and the heat of adsorption (Q ads), are calculated and discussed. SEM and Raman microscopy analysis also demonstrate the formation of a CBE inhibition film on the metal surface.

  14. Adsorption properties and inhibition of mild steel corrosion in hydrochloric solution by some newly synthesized diamine derivatives: Experimental and theoretical investigations

    Energy Technology Data Exchange (ETDEWEB)

    Herrag, L.; Hammouti, B.; Elkadiri, S.; Aouniti, A. [Laboratoire de Chimie Appliquee et Environnement, LCAE-URAC18, Faculte des Sciences, Universite Mohammed Premier, B.P. 717, M-6000 Oujda (Morocco); Jama, C. [Unite Materiaux et Transformations (UMET), Ingenierie des Systemes Polymeres, CNRS UMR 8207, ENSCL, B.P. 90108, F-59652 Villeneuve d' Ascq Cedex (France); Vezin, H. [Laboratoire de Spectrochimie Infrarouge et Raman (LASIR), UMR-CNRS 8516, Universite des Sciences et Technologies de Lille, Batiment C5, F-59655 Villeneuve d' Ascq Cedex (France); Bentiss, F., E-mail: fbentiss@enscl.f [Laboratoire de Chimie de Coordination et d' Analytique (LCCA), Faculte des Sciences, Universite Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco)

    2010-09-15

    New diamine derivatives, namely 2-[{l_brace}2-[bis-(2-hydroxyethyl)amino]ethyl{r_brace}(2-hydroxyethyl)amino]ethanol (DAME) and 2-[{l_brace}2-[bis-(2-hydroxyethyl)amino]ethyl{r_brace}(2-hydroxyethyl)amino]propanol (DAMP) were synthesised and their inhibitive action against the corrosion of mild steel in 1 M HCl solution were investigated at 308 K. The detailed study of DAME is given using gravimetric measurements and polarization curves method. Results show that DAME is a good inhibitor and inhibition efficiency reaches 91.7% at 10{sup -3} M. Tafel polarization study revealed that DAME acts as a mixed-type inhibitor. The inhibitor adsorption process in mild steel/DAME/hydrochloric acid system was studied at different temperatures (308-353 K) by means of weight loss measurements. The adsorption of DAME on steel surface obeyed Langmuir's adsorption isotherm. The kinetic and thermodynamic parameters for mild steel corrosion and inhibitor adsorption, respectively, were determined and discussed. The comparative study of inhibitive performance of the two diamine derivatives revealed that DAME is more effective than DAMP. Quantitative Structure-Activity Relationship (QSAR) approach has been conducted in attempt to correlate the corrosion inhibition properties of these diamine derivatives with their calculated quantum chemical parameters.

  15. STUDY ON THE EFFECTS OF ACID ETCHING ON AFFECTED ENAMEL

    Directory of Open Access Journals (Sweden)

    Simona Stoleriu

    2011-12-01

    Full Text Available The purpose of the study was to establish and compare the effects of ortophosphoric and hydrochloric acids on the enamel affected by incipient carious lesions with different evolution. Materials and method. 20 teeth with acute and chronic non-cavitary carious lesions were considered for the study. The teeth were sectioned in two halves through the middle of the non-cavitary lesions. The halves of 5 white spot-type lesions and of 5 brown spot-type ones were analyzed as to their surface roughness, on an atomic force microscope (AFM. 5 halves with white spot-type lesions and 5 halves with brown spot-type ones were subjected to acid etching with 37% ortophosphoric acid (Scotchbond etchant gel, 3M ESPE, and an equal number of samples was subjected to the action of 15% hydrochloric acid (ICON-etch, DMG Dental Products Ltd for 2 min, then washed with water and analyzed by AFM. Results. The initial surface roughness of the enamel was higher in the white spot–type carious lesions, comparatively with the brown spot-type ones. For both types of carious non-cavitary lesions, acid etching with phosphoric and hydrochloric acid significantly increased the surface roughness of the enamel, comparatively with the status of the enamel surface prior to etching. The hydrochloric acid led to a surface roughness significantly higher than in the case of ortophosphoric acid, in both acute and chronic non-cavitary carious lesions. The roughness values obtained through etching with ortophosphoric and hydrochloric acid were higher in the white spot-type carious lesions, comparatively with the brown spot-type ones. Conclusions. Both the 37% ortophosphoric acid and the 15% hydrochloric acid determined a significantly higher surface roughness of the enamel affected by acute and chronic non-cavitary carious lesions. The surface condition of the brown spot-type carious lesions was less significantly modified, comparatively with that of the white spot-type lesions, by the

  16. Effect of roxatidine acetate on daytime and night-time peptone-stimulated gastric acid secretion.

    Science.gov (United States)

    Hagenmüller, F

    1988-01-01

    A double-blind, randomised, crossover study in 12 healthy volunteers was performed to assess the effects of roxatidine acetate 75 mg or placebo administered at 8 am and 9 pm on peptone-stimulated hydrochloric acid secretion. In comparison to placebo, roxatidine acetate produced an average reduction of daytime hydrochloric acid output of 86% and 32%, respectively, for the 4- to 6-hour and 10- to 12-hour post-drug administration phases. In addition, roxatidine acetate produced reductions in nocturnal hydrochloric acid output of 75 to 92% with an associated rise in intragastric pH of around 2 units compared to placebo. No side effects or clinically significant alterations in haematological or biochemical values were reported following roxatidine acetate administration. These results suggest that roxatidine acetate is a potent and effective inhibitor of day and night-time intragastric acid secretion.

  17. Solvent extraction of metals with hydroxamic acids.

    Science.gov (United States)

    Vernon, F; Khorassani, J H

    1978-07-01

    Solvent extraction with hydroxamic acids has been investigated. with comparison of aliphatic and aromatic reagents for the extraction of iron, copper, cobalt and nickel. Caprylohydroxamic acid has been evaluated for use in extraction systems for titanium, vanadium, chromium, molybdenum and uranium, both in terms of acidity of aqueous phase and oxidation state of the metal. It has been established that caprylohydroxamic acid in 1-hexanol is a suitable extractant for the removal of titanium(IV), vanadium(V), chromium(VI), molybdenum(VI) and uranium(VI) from 6M hydrochloric acid.

  18. Effect of three component (aniline–formaldehyde and piperazine polymer on mild steel corrosion in hydrochloric acid medium

    Directory of Open Access Journals (Sweden)

    K.R. Ansari

    2015-10-01

    Full Text Available Polymeric Schiff base containing aniline, formaldehyde and piperazine (AFPP was synthesized and investigated as corrosion inhibitor for mild steel in 1 M HCl by weight loss measurements, electrochemical impedance spectroscopy (EIS and potentiodynamic polarization techniques. Experimental results showed that AFPP is an effective inhibitor for mild steel in 1 M HCl and exhibited 98% inhibition efficiency. Potentiodynamic polarization studies showed that AFPP is a mixed-type inhibitor predominantly cathodic type. The adsorption of inhibitor on the mild steel surface followed Langmuir adsorption isotherm. Activation energy (Ea, standard energy of adsorption (ΔG°ads, enthalpy of activation (ΔH∗, and entropy of activation (ΔS∗ of corrosion process were calculated and discussed.

  19. 40 CFR 63.1218 - What are the standards for hydrochloric acid production furnaces that burn hazardous waste?

    Science.gov (United States)

    2010-07-01

    ... discharge or cause combustion gases to be emitted into the atmosphere that contain: (1) For dioxins and... discharge or cause combustion gases to be emitted into the atmosphere that contain: (1) For dioxins and... Emissions Standards and Operating Limits for Incinerators, Cement Kilns, and Lightweight Aggregate Kilns...

  20. [Changes in the ultrastructure of the stomach mucous membrane parietal cells caused by inhibitors of hydrochloric acid secretion].

    Science.gov (United States)

    Dondukova, G V; Morozov, I A

    2002-01-01

    The study of the action of phamotidine and omeprazol on the stomach parietal cells in patients with duodenal ulcer has shown that phamotidin results in changes of secretory membrane of the parietal cells increasing its secretory potential while omeprazol reduces energetic metabolism of the lining cell by the impact on its mitochondrial apparatus. Both in children and adults with duodenal ulcer more developed mitochondrial cell activity was found after omeprazol treatment.

  1. Impact of quality parameters on the recovery of putrescine and cadaverine in fish using methanol-hydrochloric acid solvent extraction.

    Science.gov (United States)

    Richard, Nicole L; Pivarnik, Lori F; Ellis, P Christopher; Lee, Chong M

    2011-01-01

    Methanol (MeOH) extraction by AOAC Official Method 996.07 has resulted in low amine recoveries in fresh fish tissue. Addition of 25% 0.4 M HCl to the 75% methanol-water extraction solvent resulted in higher recoveries of putrescine and cadaverine. Average putrescine recovery increased from 55 to 92% in flounder, scup, bluefish, and salmon; from 92 to 98% in mackerel; and from 83 to 107% in processed mackerel. Average cadaverine recovery increased from 57 to 95% in flounder, scup, bluefish, and salmon; from 91 to 97% in mackerel; and from 92 to 108% in processed mackerel. Fish stored on ice for 12 days also showed differences between background concentrations determined with the two solvents. However, the values decreased with storage time, indicating that degradation of the protein matrix may cause more comparable measurements between the two solvents. However, consistently higher putrescine and cadaverine measurements were determined using MeOH-HCl. Although significant differences in the extraction of amines from the high-fat fish tissue were not seen between MeOH and MeOH-HCl, it would be ideal to have one solvent for biogenic amine extraction. This study confirms that MeOH-HCl is a better solvent for complete extraction and recovery of putrescine and cadaverine in fresh and processed fish tissues.

  2. Berberine as an Environmental-Friendly Inhibitor for Hot-Dip Coated Steels in Diluted Hydrochloric Acid

    Institute of Scientific and Technical Information of China (English)

    Hong Ju; Yulin Ju; Yan Li

    2012-01-01

    The inhibition effect of an excellent environmental-friendly corrosion inhibitor--berberine on hot-dip coated steels in the diluted HCI has been investigated by using quantum chemistry analysis, mass-loss tests, elec- trochemical measurements and scanning electron microscopy (SEM) observation. Calculation results show that berberine has a nearly planar structure with a number of active centers. The value of Mulliken charge, and the distribution of the highest occupied molecular orbital (HOMO) and the lower unoccupied molecular orbital (LUMO) imply that berberine has a good ability of electron exchange with metal surface. The test results indicate that inhibition efficiency (IE%) increases with the inhibitor concentration and the highest IE can reach 99%. Adsorption of berberine on the coating surface follows Langmuir adsorption isotherm with a single molecular layer by chemisorption.

  3. Corrosion Inhibition by Tithonia diversifolia (Hemsl) A. Gray leaves extract for 304 SS in hydrochloric acid solution

    Science.gov (United States)

    Firdausi, S.; Kurniawan, F.

    2016-04-01

    The inhibition effect of Tithonia diversifolia (Hemsl) A. Gray leaves extract on the corrosion phenomena of 304 SS in 1 M HCl has been studied by polarization potentiodynamic. The powder of T. diversifolia was extracted by demineralized water which was cultivated in East Java, Indonesia. The extract was characterized by FTIR spectrophotometer. The presence of T. diversifolia can inhibit the corrosion rate of 304 SS. The efficiency inhibition value of 2 g/L T. diversifolia leaves extract reached up to 77.27% at room temperature.

  4. Effect of Chemical Passivation Treatment and Flow on the Corrosion of 304 Stainless Steel in Hydrochloric Acid Solution

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Jie; Cheng, Cong Qian; Cao, Tie Shan [Dalian University of Technology, Dalian (China)

    2015-12-15

    Effects of passive film quality by chemical passivation and solution flow on the corrosion behavior of 304 stainless steel in HCl solution were investigated using a coloration indicator, and by corrosion weight loss, electrochemical polarization and element dissolution measurements. A high redness degree suggests a low passive-film integrity for 304 stainless steel following air exposure, while the minimum redness degree for the samples after chemical passivation suggests a high passive-film integrity. In the static condition, samples subjected to air exposure exhibited a high corrosion rate and preferential dissolution of Fe. Chemical passivation inhibited the corrosion rate due to the intrinsically high structural integrity of the passive film and high concentrations of Cr-rich oxides and hydroxide. Solution flow accelerated corrosion by promoting both the anodic dissolution reaction and the cathodic reaction. Solution flow also altered the preferential dissolution to fast uniform dissolution of metal elements.

  5. Synthesis of Four Triazole Compounds and Their Corrosion Inhibitive Effect on Carbon Steel in Hydrochloric Acid Medium

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-Ru; XU Min-Hua; ZHANG Shu-Sheng

    2008-01-01

    Four new 1,2,3-triazoles (3a, 3b, 4a and 4b) have been synthesized selectively via click chemistry approach and characterized by elemental analysis, IR, 1H NMR, 13C NMR and single crystal X-ray crystallographic analysis. The inhibiting action of these compounds against the corrosion of carbon steel in 1.0 mol/L HCI solution was investigated by electrochemical techniques including polarization and electrochemical impedance spectroscopy (EIS), both results of which indicate that these compounds act as good anodic inhibitors. The electrochemical study also shows that 4b is the best inhibitor among the four compounds in this work and its efficiency increases with concentration.The obtained highest IE (inhibition efficiency) of 4b is around 97%.

  6. Theoretical Study of Chloro-N-(4-methoxybenzylideneaniline Derivatives as Corrosion Inhibitors for Zinc in Hydrochloric Acid

    Directory of Open Access Journals (Sweden)

    S. Kumar

    2013-01-01

    Full Text Available The density functional theory (DFT was used to investigate the corrosion inhibition of three inhibitors on zinc. Quantum chemical parameters such as the energy of highest occupied molecular orbital (EHOMO, the energy of lowest unoccupied molecular orbital (ELUMO, energy gap (ΔE, hardness (η, softness (σ, electrophilicity index (ω, the fraction of electrons transferred (ΔN from inhibitor molecule to the metal surface, energy change when both processes occur, namely, charge transfer to the molecule and backdonation from the molecule (ΔEbackdonation, natural charge (qN, and Fukui functions have been calculated by using B3LYP/6-31+G(d basis set. The relation between the inhibition efficiency and quantum chemical parameters has been discussed in order to elucidate the inhibition mechanism of the chloro-N-(4-methoxybenzylideneaniline derivatives.

  7. Studies on adsorption and corrosion inhibitive properties of quinoline derivatives on N80 steel in 15% hydrochloric acid

    Directory of Open Access Journals (Sweden)

    K.R. Ansari

    2016-12-01

    Full Text Available This paper deals with the N80 steel corrosion protection study in 15% HCl which was carried by three quinoline derivatives namely 3-acetyl-1-(4-methylbenzylideneamino quinolin-2-one (AQ-1, 3-acetyl-1-(4 hydroxy benzylideneamino quinolin-2-one (AQ-2, 3-acetyl-1-(3-nitrobenzylideneamino quinolin-2(1H-one (AQ-3 using gravimetric, electrochemical, and quantum chemical studies. Tafel polarization showed that AQs are mixed type inhibitors but dominantly affect cathodic reaction more. The observed results reveal that AQ-1 is the best inhibitor. All the three inhibitors were found to obey the Langmuir adsorption isotherm. Scanning electron microscopy (SEM micrographs supports the protection of the N80 steel by AQs. Quantum chemical study reveals that the inhibitors have a tendency to get protonated and this protonated form has greater tendency to get adsorbed onto the N80 steel surface.

  8. Oxidative leaching process with cupric ion in hydrochloric acid media for recovery of Pd and Rh from spent catalytic converters.

    Science.gov (United States)

    Nogueira, C A; Paiva, A P; Oliveira, P C; Costa, M C; da Costa, A M Rosa

    2014-08-15

    The recycling of platinum-group metals from wastes such as autocatalytic converters is getting growing attention due to the scarcity of these precious metals and the market pressure originated by increase of demand in current and emerging applications. Hydrometallurgical treatment of such wastes is an alternative way to the most usual pyrometallurgical processes based on smelter operations. This paper focuses on the development of a leaching process using cupric chloride as oxidising agent, in HCl media, for recovery of palladium and rhodium from a spent catalyst. The chloride media allows the adequate conditions for oxidising and solubilising the metals, as demonstrated by equilibrium calculations based on thermodynamic data. The experimental study of the leaching process revealed that Pd solubilisation is clearly easier than that of Rh. The factors temperature, time, and HCl and Cu(2+) concentrations were significant regarding Pd and Rh leaching, the latter requiring higher factor values to achieve the same results. Leaching yields of 95% Pd and 86% Rh were achieved under optimised conditions (T = 80 °C, t = 4h, [HCl] = 6M, [Cu(2+)] = 0.3M).

  9. Oxidative leaching process with cupric ion in hydrochloric acid media for recovery of Pd and Rh from spent catalytic converters

    Energy Technology Data Exchange (ETDEWEB)

    Nogueira, C.A., E-mail: carlos.nogueira@lneg.pt [Laboratório Nacional de Energia e Geologia, I.P., Campus do Lumiar, 1649-038 Lisboa (Portugal); Paiva, A.P., E-mail: appaiva@fc.ul.pt [Centro de Química e Bioquímica, Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade de Lisboa, 1749-016 Lisboa (Portugal); Oliveira, P.C. [Laboratório Nacional de Energia e Geologia, I.P., Campus do Lumiar, 1649-038 Lisboa (Portugal); Costa, M.C., E-mail: mcorada@ualg.pt [Centro de Ciências do Mar, Departamento de Química e Farmácia, Faculdade de Ciências e de Tecnologia, Campus de Gambelas, 8005-139 Faro (Portugal); Costa, A.M. Rosa da, E-mail: amcosta@ualg.pt [Centro de Investigação em Química do Algarve, Departamento de Química e Farmácia, Faculdade de Ciências e de Tecnologia, Campus de Gambelas, 8005-139 Faro (Portugal)

    2014-08-15

    Highlights: • A new leaching process based on Cu{sup 2+}/HCl media for recovering Pd and Rh from spent autocatalytic converters is presented. • Palladium and rhodium were efficiently leached, with attained maximum yields of 95% and 86%, respectively. • Temperature, time, and HCl and Cu{sup 2+} concentrations were found to be significant factors in the leaching of Pd and Rh. - Abstract: The recycling of platinum-group metals from wastes such as autocatalytic converters is getting growing attention due to the scarcity of these precious metals and the market pressure originated by increase of demand in current and emerging applications. Hydrometallurgical treatment of such wastes is an alternative way to the most usual pyrometallurgical processes based on smelter operations. This paper focuses on the development of a leaching process using cupric chloride as oxidising agent, in HCl media, for recovery of palladium and rhodium from a spent catalyst. The chloride media allows the adequate conditions for oxidising and solubilising the metals, as demonstrated by equilibrium calculations based on thermodynamic data. The experimental study of the leaching process revealed that Pd solubilisation is clearly easier than that of Rh. The factors temperature, time, and HCl and Cu{sup 2+} concentrations were significant regarding Pd and Rh leaching, the latter requiring higher factor values to achieve the same results. Leaching yields of 95% Pd and 86% Rh were achieved under optimised conditions (T = 80 °C, t = 4 h, [HCl] = 6 M, [Cu{sup 2+}] = 0.3 M)

  10. Kinetics study of leaching arsenic from Ni-Mo ore roasting in dust mixture of hydrochloric and sulfuric acids

    Institute of Scientific and Technical Information of China (English)

    侯晓川; 杨润德; 李贺; 曾理; 肖连生

    2014-01-01

    The kinetics of leaching arsenic from Ni-Mo ore roasting dust was investigated. The effects including leaching temperature, particle size of the smelter dust, stirring speed, the coefficientβ(the molar ratio of sodium chlorate to arsenic in the smelter dust) and the initial H+ concentration on leaching arsenic were studied. The results indicate that the leaching of arsenic increases sharply with the decrease of particle size. The orders of reaction with respect to H+ concentration and particle size are determinted to be 1.136 and-1.806, respectively.The leaching of arsenic reaches 99% under experimental conditions, the apparent activation energy is determined to be 11.157 kJ/mol, which is consistent with the values of activation energy for diffusion model. The kinetics equation of leaching arsenic from the roasting dust could be expressed by a semi-empirical equation as 1-2/3η-(1-η)2/3=k0(c[H+])1.136r0-1.806exp[(-11157/RT)t].

  11. Electrochemical and quantum chemical studies of some indole derivatives as corrosion inhibitors for C38 steel in molar hydrochloric acid

    Energy Technology Data Exchange (ETDEWEB)

    Lebrini, M. [Laboratoire Materiaux et Molecules en Milieu Amazonien, CNRS 8172-UMR ECOFOG, Campus Trou Biran, Cayenne 97337, French Guiana (France); Robert, F. [Laboratoire Materiaux et Molecules en Milieu Amazonien, UAG-UMR ECOFOG, Campus Trou Biran, Cayenne 97337, French Guiana (France); Vezin, H. [Laboratoire de Chimie Organique et Macromoleculaire, UMR-CNRS 8009, USTL BatC4 F-59655 Villeneuve d' Ascq Cedex (France); Roos, C., E-mail: christophe.roos@guyane.univ-ag.f [Laboratoire Materiaux et Molecules en Milieu Amazonien, UAG-UMR ECOFOG, Campus Trou Biran, Cayenne 97337, French Guiana (France)

    2010-10-15

    A comparative study of 9H-pyrido[3,4-b]indole (norharmane) and 1-methyl-9H-pyrido[3,4-b]indole (harmane) as inhibitors for C38 steel corrosion in 1 M HCl solution at 25 {sup o}C was carried out. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques were applied to study the metal corrosion behavior in the absence and presence of different concentrations of these inhibitors. The OCP as a function of time were also established. Cathodic and anodic polarization curves show that norharmane and harmane are a mixed-type inhibitors. Adsorption of indole derivatives on the C38 steel surface, in 1 M HCl solution, follows the Langmuir adsorption isotherm model. The {Delta}G{sub ads}{sup o} values were calculated and discussed. The potential of zero charge (PZC) of the C38 steel in inhibited solution was studied by the EIS method, and a mechanism for the adsorption process was proposed. Raman spectroscopy confirmed that indole molecules strongly adsorbed onto the steel surface. The electronic properties of indole derivates, obtained using the AM1 semi-empirical quantum chemical approach, were correlated with their experimental efficiencies using the linear resistance model (LR).

  12. The use of Euphorbia falcata extract as eco-friendly corrosion inhibitor of carbon steel in hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    El Bribri, A. [Laboratoire de Chimie Organique, Bioorganique et Environnement, Faculté des Sciences, Université Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco); Tabyaoui, M., E-mail: hamidtabyaoui@yahoo.fr [Laboratoire de Chimie Organique, Bioorganique et Environnement, Faculté des Sciences, Université Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco); Laboratoire des Matériaux, Nanoparticules et Environnement, Université Mohamed V Agdal, Faculté des Sciences, 4 Av. Ibn Battouta, B.P. 1014 RP, M-10000 Rabat (Morocco); Tabyaoui, B. [Laboratoire de Chimie Organique, Bioorganique et Environnement, Faculté des Sciences, Université Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco); El Attari, H.; Bentiss, F. [Laboratoire de Catalyse et de Corrosion des Matériaux (LCCM), Faculté des Sciences, Université Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco)

    2013-08-15

    Euphorbia falcata L. extract (EFE) was investigated as eco-friendly corrosion inhibitor of carbon steel in 1 M HCl using gravimetric, ac impedance, polarization and scanning electron microscopy (SEM) techniques. The experimental results show that EFE is good corrosion inhibitor and the protection efficiency is increased with the EEF concentration. The results obtained from weight loss and ac impedance studies were in reasonable agreement. Impedance experimental data revealed a frequency distribution of the capacitance, simulated as constant phase element. Polarization curves indicated that EFE is a mixed inhibitor. The corrosion inhibition was assumed to occur via adsorption of EFE molecules on the metal surface. The adsorption of the E. falcata extract was well described by the Langmuir adsorption isotherm. The calculated ΔG{sub ads}{sup o} value showed that the corrosion inhibition of the carbon steel in 1 M HCl is mainly controlled by a physisorption process. - Graphical abstract: Display Omitted - Highlights: • EFE is a good eco-friendly inhibitor for the corrosion of carbon steel in 1 M HCl. • EFE acts as mixed-type inhibitor in 1 M HCl medium. • Weight loss, ac impedance and polarization methods are in reasonable agreement. • The adsorption of EFE is well described by the Langmuir adsorption isotherm.

  13. Quinoxaline derivatives as corrosion inhibitors for mild steel in hydrochloric acid medium: Electrochemical and quantum chemical studies

    Science.gov (United States)

    Olasunkanmi, Lukman O.; Kabanda, Mwadham M.; Ebenso, Eno E.

    2016-02-01

    The corrosion inhibition potential of four quinoxaline derivatives namely, 1-[3-(4-methylphenyl)-5-(quinoxalin-6-yl)-4,5-dihydropyrazol-1-yl]butan-1-one (Me-4-PQPB), 1-(3-(4-methoxyphenyl)-5-(quinoxalin-6-yl)-4,5-dihydropyrazol-1-yl)butan-1-one (Mt-4-PQPB), 1-[3-(3-methoxyphenyl)-5-(quinoxalin-6-yl)-4,5-dihydropyrazol-1-yl]butan-1-one (Mt-3-PQPB) and 1-[3-(2H-1,3-benzodioxol-5-yl)-5-(quinoxalin-6-yl)-4,5-dihydropyrazol-1-yl]butan-1-one (Oxo-1,3-PQPB) was studied for mild steel corrosion in 1 M HCl solution using electrochemical, spectroscopic techniques and quantum chemical calculations. The results of both potentiodynamic polarization and electrochemical impedance spectroscopic studies revealed that the compounds are mixed-type inhibitors and the order of corrosion inhibition efficiency at 100 ppm is Me-4-PQPB>Mt-3-PQPB>Oxo-1,3-PQPB>Mt-4-PQPB. Fourier transform infrared (FTIR) and ultraviolet-visible (UV-vis) spectroscopic analyses confirmed the presence of chemical interactions between the inhibitors and mild steel surface. The adsorption of the inhibitor molecules on mild steel surface was found to be both physisorption and chemisorption but predominantly chemisorption. The experimental data obey Langmuir adsorption isotherm. Scanning electron microscopy studies revealed the formation of protective films of the inhibitors on mild steel surface. Quantum chemical parameters obtained from density functional theory (DFT) calculations support experimental results.

  14. Electrochemical impedance study on the corrosion of Al-Pure in hydrochloric acid solution using Schiff bases

    Indian Academy of Sciences (India)

    A S Patel; V A Panchal; N K Shah

    2012-04-01

    The inhibition effect of newly synthesized Schiff bases -benzylidene benzylamine (A) and benzenemethanamine--methyl--(phenylmethylene) (B) on the corrosion behaviour of Al-Pure in 1.0 M HCl was studied using galvanostatic polarization and electrochemical impedance spectroscopy (EIS) and adsorption studies. The effects of inhibitor concentration, temperature and surface coverage are investigated. The effect of inhibitor concentration and other parameters are evaluated for different inhibitor concentrations and the probable mechanism was also proposed. The results show that (A) and (B) possess excellent inhibiting effect for the corrosion of Al-Pure and the inhibitors act as mixed type inhibitors. The inhibitors do not affect the mechanism of the electrode processes and inhibit corrosion by blocking the reaction sites. The high inhibition efficiency of (A) and (B) were due to the adsorption of inhibitor molecules on the metal surface. The decrease of surface area available for electrode reactions to take place is due to the formation of a protective film. Activation energy and free energy of adsorption have been calculated.

  15. Tested Demonstrations: Buffer Capacity of Various Acetic Acid-Sodium Acetate Systems: A Lecture Experiment.

    Science.gov (United States)

    Donahue, Craig J.; Panek, Mary G.

    1985-01-01

    Background information and procedures are provided for a lecture experiment which uses indicators to illustrate the concept of differing buffer capacities by titrating acetic acid/sodium acetate buffers with 1.0 molar hydrochloric acid and 1.0 molar sodium hydroxide. A table with data used to plot the titration curve is included. (JN)

  16. Microtensile strength of spruce pine after exposure to acids and bases

    Science.gov (United States)

    Floyd G. Manwiller; Paul R. Godfrey

    1972-01-01

    Earlywood and latewood microtensile specimens from 12 trees of Pinus glabra Wal. were subjected to 10-percent solution of 5 acids and 3 bases at 90oC for up to 3 hours. Hydrochloric and sulfuric acids were the most damaging, lowering maximum tensile strength 27 and 17 percent in earlywood and 36 and 39 percent in latewood; they...

  17. Formation of Linear Polyenes in Thermal Dehydration of Polyvinyl Alcohol, Catalyzed by Phosphotungstic Acid

    Science.gov (United States)

    Tretinnikov, O. N.; Sushko, N. I.

    2015-01-01

    In order to obtain linear polyenes in polyvinyl alcohol films via acid-catalyzed thermal dehydration of the polyvinyl alcohol, we used phosphotungstic acid as the catalyst: a safe and heat-stable solid chemical compound. We established that phosphotungstic acid, introduced as solid nanoparticles into polyvinyl alcohol films, is a more effective dehydration catalyst than hydrochloric acid, since in contrast to HCl it does not evaporate from the film during heat treatment.

  18. Flow Injection Analysis of Acid and Base using Thermo-Sensitive Resistance Coils

    OpenAIRE

    1995-01-01

    A flow injection analysis of acid-base by detecting neutralization heat is proposed. A injected sample (acid or base), combined with a carrier (deionized water), was mixed with a reagent (base or acid) stream. A change in the solution temperature was detected by passing the solution, immediately after mixing, through a stainless steel capillary tube around which a thermo-sensitive resistance was coiled. The temperature of carrier was used as a reference Hydrochloric acid solutions of 0.003 to...

  19. Determination of the base composition of deoxyribonucleic acid by measurement of the adenine/guanine ratio

    Science.gov (United States)

    Kirk, J. T. O.

    1967-01-01

    A method is described for determination of the base composition (as guanine+cytosine or adenine+thymine content) of DNA by accurate measurement of the adenine/guanine ratio. The DNA is hydrolysed with 0·03n-hydrochloric acid for 40min. to release the purines. The hydrolysate is subjected to ion-exchange chromatography on Zeo-Karb 225. Apurinic acids are eluted with 0·03n-hydrochloric acid and then guanine and adenine are eluted separately with 2n-hydrochloric acid. Guanine and adenine are each collected as a single fraction, and the amount of base in each case is determined by measuring the volume and the extinction at suitable wavelengths. For use in the calculations, millimolar extinction coefficients in 2n-hydrochloric acid of 12·09 for adenine at 262mμ, and 10·77 for guanine at 248mμ, were determined with authentic samples of bases. The method gives extremely reproducible results: from 12 determinations with calf thymus DNA the adenine/guanine molar ratio had a standard deviation of 0·011; this corresponds to a standard deviation in guanine+cytosine content of 0·2% guanine+cytosine. PMID:5626094

  20. Determination of the base composition of deoxyribonucleic acid by measurement of the adenine-granine ratio.

    Science.gov (United States)

    Kirk, J T

    1967-11-01

    A method is described for determination of the base composition (as guanine+cytosine or adenine+thymine content) of DNA by accurate measurement of the adenine/guanine ratio. The DNA is hydrolysed with 0.03n-hydrochloric acid for 40min. to release the purines. The hydrolysate is subjected to ion-exchange chromatography on Zeo-Karb 225. Apurinic acids are eluted with 0.03n-hydrochloric acid and then guanine and adenine are eluted separately with 2n-hydrochloric acid. Guanine and adenine are each collected as a single fraction, and the amount of base in each case is determined by measuring the volume and the extinction at suitable wavelengths. For use in the calculations, millimolar extinction coefficients in 2n-hydrochloric acid of 12.09 for adenine at 262mmu, and 10.77 for guanine at 248mmu, were determined with authentic samples of bases. The method gives extremely reproducible results: from 12 determinations with calf thymus DNA the adenine/guanine molar ratio had a standard deviation of 0.011; this corresponds to a standard deviation in guanine+cytosine content of 0.2% guanine+cytosine.

  1. Polarography of an acidic degradation product from cephalexin.

    Science.gov (United States)

    Nuñez-Vergara, L J; Squella, J A; Silva, M M

    1982-02-01

    2-Hydroxy-3-phenyl-6-methylpyrazine is identified as the product obtained by acidic degradation of cephalexin in the presence of formaldehyde. In 5M hydrochloric acid this product gives a well-defined reduction wave with a half-wave potential of -0.45 V vs. SCE. The wave is irreversible and diffusion-controlled. The diffusion current shows a linear relation with the cephalexin concentration and can be used for determination of cephalexin in plasma.

  2. Corrosion behaviour of WC-VC-Co hardmetals in acidic media

    CSIR Research Space (South Africa)

    Konadu, DS

    2010-09-01

    Full Text Available The effect of increasing vanadium carbide (VC) content on the corrosion behaviour of tungsten carbide – 10 wt% cobalt hard metals was investigated in 1 M hydrochloric (HCl), and sulphuric (H2SO4) acids solutions. Increasing VC content makes the open...

  3. Estimation of interfacial acidity of sodium dodecyl sulfate micelles

    Indian Academy of Sciences (India)

    Arghya Dey; G Naresh Patwari

    2011-11-01

    An enhancement in the excited state proton transfer (ESPT) processes of coumarin-102 (C-102) dye was observed upon addition of salicylic acid and hydrochloric acid in sodium dodecyl sulfate (SDS) micellar solution. The phenomenon was observed only in the micellar medium of anionic surfactant SDS and not in case of cationic (CTAB) or neutral (Trition X -100) surfactants. ESPT of C-102 was also observed in aqueous solutions but on addition of very high concentrations of hydrochloric acid. However, on comparing the ratio of the protonated species from the emission spectra in the presence and absence of SDS micelle, a conclusive estimation of the local proton concentration at the Stern layer of SDS micelles could be evaluated.

  4. The role of acid anion on the inhibition of the acidic corrosion of steel by lupine extract

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Gaber, A.M. [Chemistry Department, Faculty of Science, Alexandria University, Ibrahimia, P.O. Box 426, Alexandria 21321 (Egypt)], E-mail: ashrafmoustafa@yahoo.com; Abd-El-Nabey, B.A.; Saadawy, M. [Chemistry Department, Faculty of Science, Alexandria University, Ibrahimia, P.O. Box 426, Alexandria 21321 (Egypt)

    2009-05-15

    The inhibitive effect of lupine (Lupinous albus L.) extract on the corrosion of steel in aqueous solution of 1 M sulphuric and 2 M hydrochloric acids was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. Potentiodynamic polarization curves indicated that the lupine extract acts as a mixed-type inhibitor. EIS measurements showed that the dissolution process is under activation control. The inhibition efficiency of the extract obtained from impedance and polarization measurements was in a good agreement and was found to increase with increasing concentration of the extract. The obtained results showed that, the lupine extract could serve as an effective inhibitor for the corrosion of steel in acid media and the extract was more effective in case of hydrochloric acid. Theoretical fitting of the corrosion data to the kinetic-thermodynamic model was tested to show the nature of adsorption.

  5. Mucosal acid causes gastric mucosal microcirculatory disturbance in nonsteroidal anti-inflammatory drug-treated rats.

    Science.gov (United States)

    Funatsu, Toshiyuki; Chono, Koji; Hirata, Takuya; Keto, Yoshihiro; Kimoto, Aishi; Sasamata, Masao

    2007-01-01

    The mechanism by which nonsteroidal anti-inflammatory drugs (NSAIDs) suppress gastric mucosal blood flow is not fully understood, although the depletion of mucosal prostaglandin E2 has been proposed as one possible explanation. We investigated the role of gastric acid on gastric mucosal blood flow in NSAID-treated rats. A rat stomach was mounted in an ex vivo chamber, and gastric mucosal blood flow was measured sequentially in a 5-mm2 area of the gastric corpus using a scanning laser Doppler perfusion image system. Results showed that diclofenac (5 mg/kg s.c.) and indomethacin (10 mg/kg s.c.) did not affect gastric mucosal blood flow, although both strongly decreased mucosal prostaglandin E2 when saline was instilled into the gastric chamber. On replacement of the saline in the chamber with 100 mM hydrochloric acid, these drugs caused a decrease in gastric mucosal blood flow levels within 30 min. The specific cyclooxygenase (COX)-2 inhibitors celecoxib (50 mg/kg s.c.) and rofecoxib (25 mg/kg s.c.) did not affect mucosal prostaglandin E2 level, nor did they decrease gastric mucosal blood flow, even when hydrochloric acid was added to the chamber. Furthermore, measurement of vasoconstrictive factors present in the mucosa showed that endothelin-1 levels increased after administration of diclofenac s.c. in the presence of intragastric hydrochloric acid. This indicates that the presence of mucosal hydrochloric acid plays an important role in the NSAID-induced decrease in gastric mucosal blood flow, while the COX-1-derived basal prostaglandin E2, which is unlikely to control gastric mucosal blood flow itself, protects microcirculatory systems from mucosal hydrochloric acid.

  6. Exploring the Ideal Gas Law through a Quantitative Gasometric Analysis of Nitrogen Produced by the Reaction of Sodium Nitrite with Sulfamic Acid

    Science.gov (United States)

    Yu, Anne

    2010-01-01

    The gasometric analysis of nitrogen produced in a reaction between sodium nitrite, NaNO[superscript 2], and sulfamic acid, H(NH[superscript 2])SO[superscript 3], provides an alternative to more common general chemistry experiments used to study the ideal gas law, such as the experiment in which magnesium is reacted with hydrochloric acid. This…

  7. Exploring the Ideal Gas Law through a Quantitative Gasometric Analysis of Nitrogen Produced by the Reaction of Sodium Nitrite with Sulfamic Acid

    Science.gov (United States)

    Yu, Anne

    2010-01-01

    The gasometric analysis of nitrogen produced in a reaction between sodium nitrite, NaNO[superscript 2], and sulfamic acid, H(NH[superscript 2])SO[superscript 3], provides an alternative to more common general chemistry experiments used to study the ideal gas law, such as the experiment in which magnesium is reacted with hydrochloric acid. This…

  8. A Comparative Study on Corrosion Inhibition of Mild Steel Using Piper Nigrum L. in Different Acid Medium

    OpenAIRE

    Anand, B.; Balasubramanian, V

    2010-01-01

    The inhibition of corrosion of mild steel using Piper nigrum L in different acid medium by weight loss method was investigated. The corrosion inhibition was studied in hydrochloric acid and sulphuric acid by weight loss method at different time interval at room temperature. The result showed that the corrosion inhibition efficiency of this compound was found to vary with different time interval and different acid concentration. Also, it was found that the corrosion inhibition behavior of Pipe...

  9. THE EFFECT OF MEDIUM ON ADSORPTION OF FREE ACID BY CROSSLINKED CHITOSAN RESIN

    Institute of Scientific and Technical Information of China (English)

    PANYufang; CHENBingren; 等

    2000-01-01

    The adsorption of free acid of low concentration by crosslinked chitosan resin was followed by electrochemical experimental technique.The effect of acid concentration and the media on adsorption was discussed.The experimental results show that both the apparent rate constant and the interaction energy between the adsorbent and adsorbate are decreased while the concentration of hydrochloric acid is increased.In the adsorption system.the adsorption was effected by addiiton of organic solvent.

  10. Electrochemical Synthesis of Dendritic Polyaniline in BrФnsted Acid Ionic Liquids

    Institute of Scientific and Technical Information of China (English)

    刘宝友; 许丹倩; 徐振元

    2005-01-01

    BrФnsted acid ionic liquids were successfully applied to the electrochemical synthesis of polyaniline films on platinum electrode surfaces by using cyclic voltammetry. The scanning electron micrographs showed distinct changes in morphological structures. The films exhibited quite dense packing and good ordering of polymer dendrite as compared with those prepared using conventional hydrochloric acid, indicating that Bronsting acid ionic liquids might be promising alternatives to dual medium-dopants in the synthesis of conducting polymers.

  11. Biodiesel Production from Spent Fish Frying Oil Through Acid-Base Catalyzed Transesterification

    OpenAIRE

    Abdalrahman B. Fadhil; Mohammed M. Dheyab; Kareem M. Ahmed; Marwa H. Yahya

    2012-01-01

    Biodiesel fuels were prepared from a special type of frying oil namely spent fish frying oil through two step transesterification viz. acid-base catalyzed transesterification. Hydrochloric acid and potassium hydroxide with methanol were used for this purpose. The oil was pre-treated with (1.0 wt% HCl) and methanol to reduce free fatty acids content of the oil. Then, conditions of the base catalyzed step such as base concentration, reaction temperature, methanol to oil molar ratio and reaction...

  12. The influence of pH adjusted with different acids on the dyeability of polyester fabric

    Directory of Open Access Journals (Sweden)

    Miljkovic Milena N.

    2014-12-01

    Full Text Available The influence of using formic, oxalic, citric, tartaric, hydrochloric, nitric, sulphuric and phosphoric acid for dyebath pH adjustment was investigated upon the dyeing of polyester fabric with CI Disperse Yellow 60. The positions of colour in CIELab coordinates of the samples dyed with the addition of tested acids were assessed and compared to those dyed with the addition of acetic acid. It was found that the differences in dyeabilities obtained with the addition of citric, oxalic, hydrochloric, nitric and sulphuric acid are entirely acceptable according to both M&S 83A and CMC (2:1 standards in comparison to the dyeability obtained with the addition of acetic acid.

  13. Effects of organic acids on thermal inactivation of acid and cold stressed Enterococcus faecium.

    Science.gov (United States)

    Fernández, Ana; Alvarez-Ordóñez, Avelino; López, Mercedes; Bernardo, Ana

    2009-08-01

    In this study the adaptative response to heat (70 degrees C) of Enterococcus faecium using fresh and refrigerated (at 4 degrees C for up to 1 month) stationary phase cells grown in Brain Heart Infusion (BHI) buffered at pH 7.4 (non-acid-adapted cells) and acidified BHI at pH values of 6.4 and 5.4 with acetic, ascorbic, citric, lactic, malic and hydrochloric acids (acid-adapted cells) was evaluated. In all cases, the survival curves obtained were concave upward. A mathematical model based on the Weibull distribution accurately described the inactivation kinetic. The results indicate that previous adaptation to a low pH increased the bacterial heat resistance, whereas the subsequent cold storage of cells reduced E. faecium thermal tolerance. Fresh acid-adapted cells showed t(2.5)-values (time needed to obtain an inactivation level of 2.5 log10 cycles) ranging from 2.57 to 9.51 min, while non-acid-adapted cells showed t(2.5)-values of 1.92 min. The extent of increased heat tolerance varied with the acid examined, resulting in the following order: citric > or = acetic > malic > or = lactic > hydrochloric > or = ascorbic. In contrast, cold storage progressively decreased E. faecium thermal resistance. The t(2.5) values found at the end of the period studied were about 2-3-fold lower than those corresponding to non-refrigerated cells, although this decrease was more marked (about 5-fold) when cells were grown in buffered BHI and BHI acidified at pH 5.4 with hydrochloric acid. These findings highlight the need for a better understanding of microbial response to various preservation stresses in order to increase the efficiency of thermal processes and to indicate the convenience of counterbalancing the benefits of the hurdle concept.

  14. Facile synthesis of improved room temperature gas sensing properties of TiO2 nanostructures: Effect of acid treatment

    CSIR Research Space (South Africa)

    Tshabalala, Zamaswazi P

    2016-03-01

    Full Text Available TiO(sub2) nanoparticles were synthesized via a simple hydrothermal method in a sodium hydroxide (NaOH) aqueous solution and washed with distilled water and different concentrations of hydrochloric acid which acted as the morphological...

  15. Mitotic apparatus: the selective extraction of protein with mild acid.

    Science.gov (United States)

    Bibring, T; Baxandall, J

    1968-07-26

    The treatment of isolated mitotic apparatus with mild (pH 3) hydrochloric acid results in the extraction of less than 10 percent of its protein, accompanied by the selective morphological disappearance of the microtubules. The same extraction can be shown to dissolve outer doublet microtubules from sperm flagella. A protein with points of similarity to the flagellar microtubule protein is the major component of the extract from mitotic apparatus.

  16. The NH4+-NO3--Cl--SO42--H2O aerosol system and its gas phase precursors at a pasture site in the Amazon Basin: How relevant are mineral cations and soluble organic acids?

    NARCIS (Netherlands)

    Trebs, I.; Metzger, S.; Meixner, F.X.; Helas, G.N.; Hoffer, A.; Rudich, Y.; Falkovich, A.H.; Moura, M.A.L.; Silva, da R.S.; Artaxo, P.; Slanina, J.; Andreae, M.O.

    2005-01-01

    Real-time measurements of ammonia, nitric acid, hydrochloric acid, sulfur dioxide and the water-soluble inorganic aerosol species, ammonium, nitrate, chloride, and sulfate were performed at a pasture site in the Amazon Basin (Rondônia, Brazil). The measurements were made during the late dry season (

  17. [Survival of Vibrio parahaemolyticus serovar O3:K6 strains under acidic conditions].

    Science.gov (United States)

    Hasegawa, Junko; Hara-Kudo, Yukiko; Nishina, Tokuhiro; Konuma, Hirotaka; Kumagai, Susumu

    2002-04-01

    The survival of Vibrio parahaemolyticus serovar O3:K6 strains and other serovars in the presence of acetic, citric and hydrochloric acids were studied. There were no differences in resistance to these acids between serovar O3:K6 and the other serovars. At pH 5.6, citric acid was more effective in reducing the number of viable cells of V. parahaemolyticus than acetic acid. However, at pH 4.5, acetic acid was more effective than citric acid. The number of viable cells decreased quickly in the presence of rice vinegar or wine vinegar at pH 4.0.

  18. Experimental study on interaction between simulated sandstone and acidic fluid

    Institute of Scientific and Technical Information of China (English)

    Zhang Yongwang; Zeng Jianhu; Yu Bingsong

    2009-01-01

    In order to investigate the controlling mechanism of temperature, fluid and other factors on water-rock interaction in the diagenetic process, we performed a series of simulated experiments on the interaction between two kinds of fluids with different salinity and a composite mineral system (simulated sandstone), which contains albite, K-feldspar and other minerals. The experimental results showed that acidity was the most important factor that affected the dissolution of minerals in the composite mineral system. The lower the pH value, the more easily the minerals dissolved. At the same pH value, the dissolution abilities of different acids for various mineral components were also different. Compared to hydrochloric acid (inorganic acid), oxalic acid (organic acid) was more able to dissolve aluminosilicate minerals. However, the dissolution ability of oxalic acid for carbonate minerals was lower than that of hydrochloric acid. In the process of fluid-rock interaction,dissolution of feldspar was relatively complicated. Increase of temperature would accelerate the dissolution of feldspar. Under acidic conditions, albite had a higher dissolution rate than K-feldspar. K-feldspar could dissolve and convert into montmorillonite and kaolinite, while albite could dissolve and convert into kaolinite both at 40℃ and 80℃. Presence of organic acid, and decrease of pH value and water salinity were all favorable for the dissolution of feldspar, but weakened the ability to form clay minerals.

  19. Characterization and Photocatalytic Activity ofMixed Nanocrystalline TiO2 Powders Prepared by Xerogel-Hydrothermal Method in Different Acid Solutions

    Institute of Scientific and Technical Information of China (English)

    刘翠萍; 于涛; 谭欣

    2016-01-01

    TiO2 nanoparticles(NPs)were prepared via the hydrothermal route of TiO2 xerogel in nitric acid, hy-drochloric acid and acetic acid. The physico-chemical properties of the powders were characterized by X-ray dif-fraction(XRD)and N2 adsorption desorption techniques. The effects of the different acids on the structure(crystal phase)and texture(primary particle size and porosity)of the TiO2 powders were explored. Results indicated that acetic acid facilitated the formation and stability of pure anatase phase. On the other hand, nitric acid and hydro-chloric acid led to the transformation from anatase to rutile. The catalyst synthesized via the hydrothermal route of TiO2 xerogel in the low concentration hydrochloric acid solution(Ti-HCl-0.15)had the highest photocatalytic activ-ity than the catalysts obtained in the other two acid solutions. The effects of the different acids were discussed in terms of acid strength, chelating effect and the thermal stability of the adsorbed acidic anions.

  20. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; comparison of a nitric acid in-bottle digestion procedure to other whole-water digestion procedures

    Science.gov (United States)

    Garbarino, John R.; Hoffman, Gerald L.

    1999-01-01

    A hydrochloric acid in-bottle digestion procedure is used to partially digest wholewater samples prior to determining recoverable elements by various analytical methods. The use of hydrochloric acid is problematic for some methods of analysis because of spectral interference. The inbottle digestion procedure has been modified to eliminate such interference by using nitric acid instead of hydrochloric acid in the digestion. Implications of this modification are evaluated by comparing results for a series of synthetic whole-water samples. Results are also compared with those obtained by using U.S. Environmental Protection Agency (1994) (USEPA) Method 200.2 total-recoverable digestion procedure. Percentage yields that use the nitric acid inbottle digestion procedure are within 10 percent of the hydrochloric acid in-bottle yields for 25 of the 26 elements determined in two of the three synthetic whole-water samples tested. Differences in percentage yields for the third synthetic whole-water sample were greater than 10 percent for 16 of the 26 elements determined. The USEPA method was the most rigorous for solubilizing elements from particulate matter in all three synthetic whole-water samples. Nevertheless, the variability in the percentage yield by using the USEPA digestion procedure was generally greater than the in-bottle digestion procedure, presumably because of the difficulty in controlling the digestion conditions accurately.

  1. The corrosion behaviour of WC-VC-Co hardmetals in acidic media

    Energy Technology Data Exchange (ETDEWEB)

    Konadu, D.S.; Merwe, J. van der [DST/NRF Centre of Excellence in Strong Materials, School of Chemical and Metallurgical Engineering, University of the Witwatersrand, P.O. Private Bag 3, WITS 2050 (South Africa); Potgieter, J.H. [School of Biology, Chemistry and Health Sciences, Division of Chemistry and Materials, Manchester Metropolitan University, Oxford Road, Manchester M 1 5GD (United Kingdom); Potgieter-Vermaak, S. [School of Chemistry, University of the Witwatersrand, P.O. Private Bag 3, WITS 2050 (South Africa); Machio, C.N., E-mail: cmachio@csir.co.z [Council for Scientific and Industrial Research (CSIR), Materials Science and Manufacturing, P.O. Box 395, PRETORIA 0001 (South Africa)

    2010-09-15

    The effect of increasing vanadium carbide (VC) content on the corrosion behaviour of tungsten carbide - 10 wt% cobalt hardmetals was investigated in 1 M hydrochloric (HCl), and sulphuric (H{sub 2}SO{sub 4}) acids solutions. Increasing VC content makes the open circuit potential (OCP) in the test solutions more negative than the base alloy. Specimens exhibited pseudo passivation in all the test solutions. Increasing VC led to decreasing corrosion current density. However, the corrosion current densities during chronoamperometric tests were lower for 0 wt% VC. XRD and Raman spectroscopy showed that hydrated WO{sub 3} formed in the surface films of all specimens in hydrochloric acid (HCl), while hydrated vanadyl sulphate also formed for higher VC content specimens in sulphuric acid (H{sub 2}SO{sub 4}).

  2. Cellulose with a High Fractal Dimension Is Easily Hydrolysable under Acid Catalysis

    Directory of Open Access Journals (Sweden)

    Mariana Díaz

    2017-05-01

    Full Text Available The adsorption of three diverse amino acids couples onto the surface of microcrystalline cellulose was studied. Characterisation of modified celluloses included changes in the polarity and in roughness. The amino acids partially break down the hydrogen bonding network of the cellulose structure, leading to more reactive cellulose residues that were easily hydrolysed to glucose in the presence of hydrochloric acid or tungstophosphoric acid catalysts. The conversion of cellulose and selectivity for glucose was highly dependent on the self-assembled amino acids adsorbed onto the cellulose and the catalyst.

  3. Acid Activation of Natural Zeolite with High Content of Iron Oxides in Creation of Selective Sorbents and Catalysts

    Directory of Open Access Journals (Sweden)

    Kadirbekov Kairat

    2017-01-01

    Full Text Available The paper studies the influence of the nature of modifying acids (mineral, organic and heteropolyacids, and their combination on the composition and structure of the iron oxide rich clinoptilolit from Shankanay field in Kazakhstan for creation of selective catalysts in hydracarbon processing and sorbents for extracting ions of lanthanide and actinide elements. It is shown that sequential processing of natural zeolite in optimal conditions, by hydrochloric and sulfosalicylic acids lead to intensive decationization and dealumination, as well as maximum removal of iron ions from the zeolite framework without destroying it. It is found that the combination of activated clinoptilolite with hydrochloric acid and phosphotungstic heteropolyacid contributes to obtain catalyst system with high surface area and acidity.

  4. Corrosion Behavior of Nickel Alloys in Wet Hydrofluoric Acid

    Energy Technology Data Exchange (ETDEWEB)

    Rebak, R B

    2004-02-06

    Hydrofluoric acid is a water solution of hydrogen fluoride (HF). Hydrofluoric acid is used widely in diverse types of industrial applications; traditionally, it is used in pickling solutions in the metal industry, in the fabrication of chlorofluorocarbon compounds, as an alkylation agent for gasoline and as an etching agent in the industry of glass. In recent years, hydrofluoric acid has extensively been used in the manufacture of semiconductors and microelectronics during the wet chemical cleaning of silicon wafers. Hydrofluoric acid can be considered a reducing acid and although it is chemically classified as weaker than, for example, sulfuric or hydrochloric acids, it is extremely corrosive. This acid is also particularly toxic and poses greater health hazard than most other acids. The corrosion behavior of metals in hydrofluoric acid has not been as systematic studied in the laboratory as for other common inorganic acids. This is largely because tests using hydrofluoric acid cannot be run in standard equipment and because of the toxic nature of this acid. Moreover, short-term weight loss laboratory corrosion tests in hydrofluoric acid can be frustrating since the results are not as highly reproducible as in the case of other acids such as sulfuric or hydrochloric. One of the reasons is because hydrofluoric acid commonly attacks the coupons used for testing in a non-uniform manner. That is, the corrosive power of this acid is not aimed to uniform thinning but mostly to localized penetration below the skin of the metal in the form of thin cracks, voids, pits, trenches and sometimes intergranular attack. Figure 1 shows the cross section of a coupon of Alloy 600 (N06600) exposed for 336 h to the vapor phase of a solution of 20% HF at 93 C. In cases where internal penetration occurs such as in Figure 1, it may not be recommended to use corrosion rates based on weight loss for material selection.

  5. AUTH Regional Climate Model Contributions to EURO-CORDEX. Part II

    Science.gov (United States)

    Katragkou, E.; Gkotovou, I.; Kartsios, S.; Pavlidis, V.; Tsigaridis, K.; Trail, M.; Nazarenko, L.; Karacostas, Theodore S.

    2017-01-01

    Regional climate downscaling techniques are being increasingly used to provide higher-resolution climate information than is available directly from contemporary global climate models. The Coordinated Regional Climate Downscaling Experiment (CORDEX) initiative was build to foster communication and knowledge exchange between regional climate modelers. The Department of Meteorology and Climatology of the Aristotle University of Thessaloniki has been contributing to the CORDEX initiative since 2010, with regional climate model simulations over the European domain (EURO-CORDEX). Results of this work are presented here, including two hindcasts and a historical simulation with the Weather Research Forecasting model (WRF), driven by ERA-interim reanalysis and the NASA Earth System Goddard Institute for Space Studies (GISS) ModelE2, respectively. Model simulations are evaluated with the EOBS climatology and the model performance is assessed.

  6. AUTH Regional Climate Model Contributions to EURO-CORDEX. Part II

    Science.gov (United States)

    Katragkou, E.; Gkotovou, I.; Kartsios, S.; Pavlidis, V.; Tsigaridis, K.; Trail, M.; Nazarenko, L.; Karacostas, Theodore S.

    2017-01-01

    Regional climate downscaling techniques are being increasingly used to provide higher-resolution climate information than is available directly from contemporary global climate models. The Coordinated Regional Climate Downscaling Experiment (CORDEX) initiative was build to foster communication and knowledge exchange between regional climate modelers. The Department of Meteorology and Climatology of the Aristotle University of Thessaloniki has been contributing to the CORDEX initiative since 2010, with regional climate model simulations over the European domain (EURO-CORDEX). Results of this work are presented here, including two hindcasts and a historical simulation with the Weather Research Forecasting model (WRF), driven by ERA-interim reanalysis and the NASA Earth System Goddard Institute for Space Studies (GISS) ModelE2, respectively. Model simulations are evaluated with the EOBS climatology and the model performance is assessed.

  7. Effects of organic and inorganic acids on phosphorus release from municipal sludge.

    Science.gov (United States)

    Pakdil, N B; Filibeli, A

    2007-01-01

    This paper reports on the effects of inorganic acids (sulphuric acid, hydrochloric acid, nitric acid) and organic acids (citric acid, oxalic acids) for phosphorus recovery from sludge and struvite precipitation results. It was observed that both inorganic acid and organic acids were effective at phosphorus release. The studies on precipitation of released phosphorus from sludge as magnesium ammonium phosphate (struvite) were also done using nitric and oxalic acids. Phosphorus and heavy metals of leachate were analyzed before and after precipitation. It was observed that heavy metal concentrations in the extracted samples decrease after precipitation. Precipitation was accomplished by using extract derived with nitric acid; however, in oxalic acid applications, it was not achieved. When the chemical constituents of the dried material were examined oxygen, sodium and nitrogen were found to be the major elements.

  8. Fatty acids in female’s gonads of the Red Sea fish Rhabdosargus sarba during the spawning season

    OpenAIRE

    Suhaila Qari; Samia Moharram; Safaa Alowaidi

    2014-01-01

    Objective: To determine the fatty acids profiles in female fish, Rhabdosargus sarba (R. sarba) from the Red Sea during the spawning season. Methods: Monthly individual R. sarba were obtained from Bangalah market in Jeddah, Red Sea and transported to the laboratory in ice aquarium. The total length, standard length and weight were measured, fishes were dissected. Ovaries were removed, weighed and 10 mL of concentrated hydrochloric acid were added to 10 g of the ovary in a conica...

  9. Effect of acid concentration and treatment time on acid-alcohol modified jackfruit seed starch properties.

    Science.gov (United States)

    Dutta, Himjyoti; Paul, Sanjib Kumar; Kalita, Dipankar; Mahanta, Charu Lata

    2011-09-15

    The properties of starch extracted from jackfruit (Artocarpus heterophyllus Lam.) seeds, collected from west Assam after acid-alcohol modification by short term treatment (ST) for 15-30min with concentrated hydrochloric acid and long term treatment (LT) for 1-15days with 1M hydrochloric acid, were investigated. Granule density, freeze thaw stability, solubility and light transmittance of the treated starches increased. A maximum decrease in the degree of polymerisation occurred in ST of 30min (2607.6). Jackfruit starch had 27.1±0.04% amylose content (db), which in ST initially decreased and then increased with the severity of treatment; in LT the effect was irregular. The pasting profile and granule morphology of the treated samples were severely modified. Native starch had the A-type crystalline pattern and crystalline structure increased on treatment. FTIR spectra revealed slight changes in bond stretching and bending. Colour measurement indicated that whiteness increased on treatment. Acid modified jackfruit seed starch can have applications in the food industry.

  10. Method for determination of uranium isotopes in environmental samples by liquid-liquid extraction with triisooctylamine/xylene in hydrochloric media and alpha spectrometry.

    Science.gov (United States)

    Popov, L

    2012-10-01

    Alternative method for determination of uranium isotopes in various environmental samples is presented. The method is based on total decomposition of the solid materials and preconcentration of liquid samples. The separation of uranium from interfering radionuclides and stable matrix elements is attained by liquid-liquid extraction with triisooctylamine/xylene in hydrochloric media. After the additional removal of stable iron by extraction with diisopropyl ether, purified uranium is electrodeposited on stainless steel disks and measured by alpha spectrometry. The analytical method has been successfully applied to the determination of uranium isotopes in water and bottom sediments from the rivers Danube, Ogosta and Tzibritza in Northwestern Bulgaria. The analytical quality was checked by analyzing reference materials with different matrices.

  11. Effect of Morinda Tinctoria Leaves Extract on the Corrosion Inhibition of Mild Steel in Acid Medium

    Institute of Scientific and Technical Information of China (English)

    K.Krishnaveni; J.Ravichandran; A.Selvaraj

    2013-01-01

    The Morinda tinctoria (MT) plant leaves extract was prepared in aqueous and hydrochloric acid media and was used as corrosion inhibitor for mild steel in hydrochloric acid medium.MT is found to be an efficient inhibitor at room temperature and the efficiency decreases with increase in temperature.Results from colorimetric studies predict the amount of iron present in the test solution and the percentage inhibition efficiency values calculated from this data fit well with the weight loss experiments.The AC impedance studies reveal that the mild steel surface is positively charged and the process of inhibition is through charge transfer.Polarisation studies indicate the mixed nature of the inhibitor.Thermodynamic parameters obtained predict that the process of inhibition is a spontaneous one.

  12. Acid etching process for fabrication of Bi2Sr2CaCu2O8+x stack

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jie; CHEN Jian; WU JingBo; KANG Lin; XU WeiWei; WU PeiHeng

    2007-01-01

    We adopted a new method, acid etching process, to fabricate the intrinsic Josephson junctions based on the Bi2Sr2CaCu2O8+x single crystals. By soaking the crystals into the dilute hydrochloric acid, we fabricated a junction stack successfully, and meantime made the surrounding area insulated. A certain concentration of hydrochloric acid was used to maintain the roughness of the modified layer. The current-voltage characteristic was achieved through the four terminal measurement. We could control the junctions' number by changing the concentration and the soaking time. We also found that the thickness of the stack was equal to the average height of the insulation layer. Such a simple, convenient and controllable fabrication method with a high yield might widen the applications of the intrinsic Josephson junctions.

  13. An Effective Acid Combination for Enhanced Properties and Corrosion Control of Acidizing Sandstone Formation

    Science.gov (United States)

    Umer Shafiq, Mian; Khaled Ben Mahmud, Hisham

    2016-03-01

    To fulfill the demand of the world energy, more technologies to enhance the recovery of oil production are being developed. Sandstone acidizing has been introduced and it acts as one of the important means to increase oil and gas production. Sandstone acidizing operation generally uses acids, which create or enlarge the flow channels of formation around the wellbore. In sandstone matrix acidizing, acids are injected into the formation at a pressure below the formation fracturing pressure, in which the injected acids react with mineral particles that may restrict the flow of hydrocarbons. Most common combination is Hydrofluoric Acid - Hydrochloric with concentration (3% HF - 12% HCl) known as mud acid. But there are some problems associated with the use of mud acid i.e., corrosion, precipitation. In this paper several new combinations of acids were experimentally screened to identify the most effective combination. The combinations used consist of fluoboric, phosphoric, formic and hydrofluoric acids. Cores were allowed to react with these combinations and results are compared with the mud acid. The parameters, which are analyzed, are Improved Permeability Ratio, strength and mineralogy. The analysis showed that the new acid combination has the potential to be used in sandstone acidizing.

  14. 盐酸二甲双胍致不良反应1例%The hydrochloric acid two armor biguanides send respond 1 example

    Institute of Scientific and Technical Information of China (English)

    林莉莉

    2010-01-01

    糖尿病是一种常见病及多发病,往往需要终身治疗,随着糖尿病发病率的不断上升,占糖尿病患者总数90%以上的2型糖尿病患者,治疗方案较多,在药物选择原则上,除了安全性和有效性外,盐酸二甲双胍是治疗糖尿病药物中最经济的品种之一,盐酸二甲双胍不仅能降血糖,且有调节血脂、改变患者对胰岛素敏感性等作用,药物不经肝脏代谢,以原型经尿排出体外,在体内易消除,且能保护心血管免受损害,而且不会引起低血糖.因此,盐酸二甲双胍是治疗2型糖尿病的良好药物.盐酸二甲双胍(Metformin hydrochloride,MFH)是双胍类抗糖尿病药,为目前治疗Ⅱ型糖尿病的首选药物.MFH在胃肠道的吸收不完全,主要吸收部位在小肠.

  15. Electrochemical and quantum chemical calculations on 4,4-dimethyloxazolidine-2-thione as inhibitor for mild steel corrosion in hydrochloric acid

    Science.gov (United States)

    Musa, Ahmed Y.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar; Rahoma, Abdalhamid Ahmad B.; Mesmari, Hussein

    2010-04-01

    The inhibition ability of 4,4-dimethyloxazolidine-2-thione (DMT) for mild steel corrosion in a 1 M HCl solution at 30 °C was studied by means of potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) technique, and scanning electron microscopy (SEM). Quantum chemical calculation based on PM3 method was performed on DMT. The molecule structural parameters, such as the frontier molecular orbital energy HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital), the charge distribution and the fraction of electrons (Δ N) transfer from inhibitor to mild steel were calculated and discussed. Results showed that DMT performed as good inhibiting effect for the corrosion of mild steel in a 1 M HCl solution and inhibition efficiency is higher than 82% at 4 × 10 -3 M DMT. Results indicate that the inhibition efficiencies increased with the concentration of DMT and the area containing S atom is most possible site for bonding the mild steel surface by donating electrons to the metal. Adsorption of the inhibitor on the mild steel surface followed Langmuir adsorption isotherm and the value of the free energy of adsorption Δ G○ads indicated that the adsorption of DMT molecule was a spontaneous process and was typical of chemisorptions.

  16. THE COMBINATION OF GELATIN WITH HYDROCHLORIC ACID : II. NEW DETERMINATIONS OF THE ISOELECTRIC POINT AND COMBINING CAPACITY OF A PURIFIED GELATIN.

    Science.gov (United States)

    Hitchcock, D I

    1929-03-20

    1. Cooper's gelatin purified according to Northrop and Kunitz exhibited a minimum of osmotic pressure and a maximum of opacity at pH 5.05 +/-0.05. The pH of solutions of this gelatin in water was also close to this value. It is inferred that such gelatin is isoelectric at this pH and not at pH 4.70. 2. Hydrogen electrode measurements with KCl-agar junctions were made with concentrated solutions of this gelatin in HCl up to 0.1 M. The combination curve calculated from these data is quite exactly horizontal between pH 2 and 1, indicating that 1 gm. of this gelatin can combine with a maximum of 9.35 x 10(-4) equivalents of H(+). 3. Conductivity titrations of this gelatin with HCl gave an endpoint at 9.41 (+/-0.05) x 10(-4) equivalents of HCl per gram gelatin. 4. E.M.F. measurements of the cell without liquid junction, Ag, AgCl, HCl + gelatin, H(2), lead to the conclusion that this gelatin in 0.1 M HCl combines with a maximum of 9.4 x 10(-4) equivalents of H(+) and 1.7 x 10(-4) equivalents of Cl(-) per gram gelatin.

  17. 啤酒中戊聚糖的测定--地衣酚-盐酸法%Orcinol Hydrochloric Acid Method for Determination of Pentosans in Beer

    Institute of Scientific and Technical Information of China (English)

    李胤; 陆健; 顾国贤

    2003-01-01

    研究了地衣酚-盐酸法测定啤酒及麦汁中的戊聚糖,探讨了实验条件,建立了以双波长吸光度差值的方法测定啤酒和麦汁中的戊聚糖.当参加反应的3.0 mL的溶液中木糖的含量为0~200 μg时,反应液吸光度的变化符合比摩尔定律,标样的回收率在91.9%~106.9%之间.用此法测得的市售啤酒中戊聚糖含量在906~2 121 mg/L之间.

  18. SYNERGISM OF CORROSION INHIBITION OF SDEDTC AND BAA FOR STEEL IN HYDROCHLORIC ACID MEDIUM%SDEDTC和BAA对钢的缓蚀协同效应研究

    Institute of Scientific and Technical Information of China (English)

    范洪波; 胡勇有; 郑家燊

    2005-01-01

    采用电子探针微观测试手段探讨了金属表面膜的特征,得到了丰富的表面膜微观信息;利用静态挂片、极化曲线和交流阻抗测量的结果,发现氨荒酸盐化合物二乙基二硫代氨基甲酸钠(Sodium Diethyl Dithiocarbamate,SDEDTC)和2-苯甲酰基-3-羟基-1-丙烯(2-Benzoylallyl Alcohol,BAA)存在缓蚀协同效应.

  19. Electrochemical and theoretical investigation of the inhibitory effect of two Schiff bases of benzaldehyde for the corrosion of aluminium in hydrochloric acid

    Science.gov (United States)

    Naik, U. J.; Jha, P. C.; Lone, M. Y.; Shah, R. R.; Shah, N. K.

    2016-12-01

    The corrosion inhibition effect of o-Aminophenol-N-Benzylidene (o-AmphNB) and o-Anisidene-N-Benzylidene (o-AnsNB) for pure Aluminium in 1 M HCl at different concentrations of two different inhibitors were investigated by means of weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The values of Δ Gadso revealed that the adsorption mechanism of these molecules on aluminium surface is competitive phenomenon between chemical and physical adsorption. Potentiodynamic polarization parameters revealed the mixed mode of inhibition with predominance of cathodic inhibition. The impedance results showed that with increase in concentration of inhibitor, charge transfer resistance increases while double layer capacitance decreases. Quantum chemical calculations based on density functional theory (DFT) method were performed on o-AmphNB and o-AnsNB to determine the relationship between molecular structures and their inhibition efficiencies. Correlation analysis concluded that the inhibition effect of inhibitors could be explained in terms of electronic properties.

  20. A Comparative Study of the Inhibitory Effect of the Extracts of Ocimum sanctum, Aegle marmelos, and Solanum trilobatum on the Corrosion of Mild Steel in Hydrochloric Acid Medium

    Directory of Open Access Journals (Sweden)

    M. Shyamala

    2011-01-01

    Full Text Available A comparative study of the inhibitory effect of plant extracts, Ocimum sanctum, Aegle marmelos, and Solanum trilobatum, on the corrosion of mild steel in 1N HCl medium was investigated using weightloss method, electrochemical methods, and hydrogen permeation method. Polarization method indicates plant extracts behave as mixed-type inhibitor. The impedance method reveals that charge-transfer process mainly controls the corrosion of mild steel. On comparison, maximum inhibition efficiency was found in Ocimum sanctum with 99.6% inhibition efficiency at 6.0% v/v concentration of the extract. The plant extracts obey Langmuir adsorption isotherm. The SEM morphology of the adsorbed protective film on the mild steel surface has confirmed the high performance of inhibitive effect of the plant extracts. From hydrogen permeation method, all the plant extracts were able to reduce the permeation current. The reason for the reduced permeation currents in presence of the inhibitors may be attributed to the slow discharge step followed by fast electrolytic desorption step. Results obtained in all three methods were very much in good agreement in the order Ocimum sanctum > Aegle marmelos > Solanum trilobatum.

  1. Application of electrochemical frequency modulation for monitoring corrosion and corrosion inhibition of iron by some indole derivatives in molar hydrochloric acid

    Energy Technology Data Exchange (ETDEWEB)

    Khaled, K.F. [Electrochemistry Research Laboratory, Chemistry Department, Faculty of Education, Ain Shams University, Roxy, Cairo (Egypt)], E-mail: khaled@asunet.shams.edu.eg

    2008-11-15

    The corrosion inhibition effect of four indole derivatives, namely indole (IND), benzotriazole (BTA), benzothiazole (BSA) and benzoimidazole (BIA), have been used as possible corrosion inhibitors for pure iron in 1 M HCl. In this study, electrochemical frequency modulation, EFM was used as an effective method for corrosion rate determination in corrosion inhibition studies. By using EFM measurements, corrosion current density was determined without prior knowledge of Tafel slopes. Corrosion rates obtained using EFM, were compared to that obtained from other chemical and electrochemical techniques. The results obtained from EFM, EIS, Tafel and weight loss measurements were in good agreement. Tafel polarization measurements show that indole derivatives are cathodic-type inhibitors. Molecular simulation studies were applied to optimize the adsorption structures of indole derivatives. The inhibitor/iron/solvent interfaces were simulated and the adsorption energies of these inhibitors were calculated. Quantum chemical calculations have been performed and several quantum chemical indices were calculated and correlated with the corresponding inhibition efficiencies.

  2. "De Novo"-synthesis of chlorinated biphenyls, dibenzofurans and dibenzo-p-dioxins in the fly ash catalyzed reaction of toluene with hydrochloric acid

    NARCIS (Netherlands)

    Leer, E.W.B. de; Lexmond, R.J.; Zeeuw, M.A. de

    1989-01-01

    Toluene is converted into benzaldehyde and halogenated aromatic oxidation products in an air atmosphere at 425 °C with fly ash from a municipal waste incineration plant as the catalyst. Several halogenated products such as chlorinated and brominated benzenes, biphenyls and traces of PCDDs/PCDFs coul

  3. "De Novo"-synthesis of chlorinated biphenyls, dibenzofurans and dibenzo-p-dioxins in the fly ash catalyzed reaction of toluene with hydrochloric acid

    NARCIS (Netherlands)

    Leer, E.W.B. de; Lexmond, R.J.; Zeeuw, M.A. de

    1989-01-01

    Toluene is converted into benzaldehyde and halogenated aromatic oxidation products in an air atmosphere at 425 °C with fly ash from a municipal waste incineration plant as the catalyst. Several halogenated products such as chlorinated and brominated benzenes, biphenyls and traces of PCDDs/PCDFs

  4. Effect of f-electron configurations on the adsorption of trivalent f-elements on tertiary pyridine resin in hydrochloric acid/alcohol mixed solvents

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Atsushi; Suzuki, Tatsuya; Aida, Masao; Ohtake, Kouhei; Fujii, Yasuhiko; Itoh, Keisuke; Hara, Mitsuo; Mitsugashira, Toshiaki

    2004-07-14

    The separation of trivalent actinides (An) from lanthanides (Ln) is difficult because of their chemical similarities although it is necessary for various fields such as nuclear fuel-cycle process. In the present study, it was observed that the trivalent An (Am{sup 3+}, Cm{sup 3+} and Cf{sup 3+}) were adsorbed on tertiary pyridine type resins far more strongly than the Ln in HCl (LiCl solution)/methanol mixed solvents and the An were separated from the Ln by using a single separation process. On the other hand, the Dowex 1 x 8 showed no adsorption in the same conditions. Therefore, there is a possibility that the adsorption of An and Ln cations is caused by the complexation of the cations with the tertiary pyridine groups of the resins, not by the ionic interaction. There seems to be some relationship between the distribution coefficients (K{sub d}) of trivalent f-elements (i.e. An and Ln) and the f-electron configurations of their cations, and their ionic size.

  5. A thermodynamical, electrochemical and surface investigation of Bis (indolyl methanes as Green corrosion inhibitors for mild steel in 1 M hydrochloric acid solution

    Directory of Open Access Journals (Sweden)

    Chandrabhan Verma

    2016-10-01

    Full Text Available The influence of three Bis (indolyl methanes (BIMs namely, 3,3′-((4-nitrophenyl methylene bis (1H-indole (BIM-1, 3,3′-(phenyl methylene bis (1H-indole (BIM-2 and 4-((1H-indol-2-yl(1H-indol-3-yl methyl phenol (BIM-3 on the mild steel corrosion in 1 M HCl was studied by weight loss, electrochemical, scanning electron microscopy (SEM, and dispersive X-ray spectroscopy (EDX methods. Results showed that BIM-3 shows maximum inhibition efficiency of 98.06% at 200 mg L−1 concentration. Polarization study revealed that the BIMs act as mixed type inhibitors. Adsorption of BIMs on the mild steel surface obeyed the Langmuir adsorption isotherm. The weight loss and electrochemical results were well supported by SEM and EDX studies.

  6. The Effects of Various Acid Catalyst on the Esterification of Jatropha Curcas Oil based Trimethylolpropane Ester as Biolubricant Base Stock

    OpenAIRE

    Noor Hafizah Arbain; Jumat Salimon

    2011-01-01

    Biolubricant production of trimethylolpropane ester (ET) was conducted via esterification of fatty acid (FA) of Jatropha curcas oil with trimethylolpropane (TMP). The condition for this reaction was as follows: temperature was 150 °C, time of reaction was 3 hours, molar ratio of FA: TMP was 4:1 and 2% wt/wt concentrated catalyst (based on weight of FA). Different catalyst was used in this reaction such as perchloric acid, sulfuric acid, p-toluenesulfonic acid, hydrochloric acid and nitric aci...

  7. Inhibition of the Corrosion of Mild Steel in Acid Media by Naturally Occurring Acacia Senegal

    Directory of Open Access Journals (Sweden)

    Urvija Garg

    2010-01-01

    Full Text Available The inhibition of corrosion of mild steel in HCl solution by naturally occurring Acacia Senegal has been studied in relation to the concentration of inhibitor and concentration of corrosive medium. It has been observed that the Acacia Senegal alcoholic extract acts as a good corrosion inhibitor in hydrochloric acid solution and the adsorption of the extract provides a good protection against mild steel corrosion.

  8. Evaluation of ventilatory therapy for acid aspiration.

    Science.gov (United States)

    Flint, L; Gosdin, G; Carrico, C J

    1975-10-01

    Aspiration of hydrochloric acid in experimental animals results in severe, progressive hypoxia which is due to intrapulmonary shunting and depressed cardiac output. This preparation is useful therefore in studying the therapy of hypoxia. Mongrel dogs were subjected to acid aspiration and the effects of several ventilatory patterns on intrapulmonary shunt fractions and lung water accumulation observed. The combination of large tidal volumes (30 c.c. per kilogram) with positive end-expiratory pressure was effective in preventing intrapulmonary shunting and other ventilatory patterns were ineffective. Pulmonary edema uniformly followed acid aspiration and was not affected by ventilatory therapy. When ventilatory therapy was delayed for 4 hours, the progression of shunting apparently was limited, but the existing shunt was not reduced.

  9. Simultaneous hydrolysis-esterification of wet microalgal lipid using acid.

    Science.gov (United States)

    Takisawa, Kenji; Kanemoto, Kazuyo; Kartikawati, Muliasari; Kitamura, Yutaka

    2013-12-01

    This research demonstrated hydrolysis of wet microalgal lipid and esterification of free fatty acid (FFA) using acid in one-step process. The investigation of simultaneous hydrolysis-esterification (SHE) of wet microalgal lipid was conducted by using L27 orthogonal design and the effects of water content, volume of sulphuric acid, volume of methanol, temperature and time on SHE were examined. As a result, water content was found to be the most effective factor. The effects of various parameters on fatty acid methyl ester (FAME) content and equilibrium relation between FAME and FFA were also examined under water content 80%. Equimolar amounts of sulphuric acid and hydrochloric acid showed similar results. This method has great potential in terms of biodiesel production from microalgae since no organic solvents are used.

  10. New Development of Acid Regeneration in Steel Pickling Plants

    Institute of Scientific and Technical Information of China (English)

    W F Kladnig

    2008-01-01

    For acid pickling heat treated mild steel and steel products,up to the middle of the last century,sulfuric acid was primarily in use,which has been replaced stepwise by hydrochloric acid since the sixties.During this time,the pickling of high alloyed steel with hydrofluoric acid or mixtures for hydrofluoric acid together with nitric acid has also been applied on industrial scale.The technologies used by several plant contractors hereby show considerable differences in their engineering.The study provides a survey of the progress in the state of art of regeneration technology as well as the use of different pickling media in the form of a review on existing technologies as well as improvements done within the recent years in the area.

  11. Investigation of Gas-Sensing Property of Acid-Deposited Polyaniline Thin-Film Sensors for Detecting H2S and SO2

    Directory of Open Access Journals (Sweden)

    Xingchen Dong

    2016-11-01

    Full Text Available Latent insulation defects introduced in manufacturing process of gas-insulated switchgears can lead to partial discharge during long-time operation, even to insulation fault if partial discharge develops further. Monitoring of decomposed components of SF6, insulating medium of gas-insulated switchgear, is a feasible method of early-warning to avoid the occurrence of sudden fault. Polyaniline thin-film with protonic acid deposited possesses wide application prospects in the gas-sensing field. Polyaniline thin-film sensors with only sulfosalicylic acid deposited and with both hydrochloric acid and sulfosalicylic acid deposited were prepared by chemical oxidative polymerization method. Gas-sensing experiment was carried out to test properties of new sensors when exposed to H2S and SO2, two decomposed products of SF6 under discharge. The gas-sensing properties of these two sensors were compared with that of a hydrochloric acid deposited sensor. Results show that the hydrochloric acid and sulfosalicylic acid deposited polyaniline thin-film sensor shows the most outstanding sensitivity and selectivity to H2S and SO2 when concentration of gases range from 10 to 100 μL/L, with sensitivity changing linearly with concentration of gases. The sensor also possesses excellent long-time and thermal stability. This research lays the foundation for preparing practical gas-sensing devices to detect H2S and SO2 in gas-insulated switchgears at room temperature.

  12. Removal of Chloroform from Hydrochloride Acid Solution Using Fine Powder of Polymer as Adsorbent

    Institute of Scientific and Technical Information of China (English)

    LU,Yingzhou; QUE,Yong; LI,Chunxi; MENG,Hong; WANG,Zihao

    2009-01-01

    In order to choose a suitable adsorbent for the removal of chloroform from its hydrochloric acid solution,the adsorptive ability of some polymer adsorbents was investigated in terms of their adsorption curves in water and 20% hydrochloric acid solutions at 298.15 K,and compared with that of active carbon (AC) and solid paraffin (SP).The adsorbents studied include the fine powders of chlorinated rubber (CR),polypropylene (PP),chlorinated polypropylene (CPP) and polyvinylchloride (PVC).The results showed that the adsorption behavior followed the Langmuir equation and the adsorption ability of these adsorbents followed the order AC > PVC > CR > PP > CPP> SP.This order is basically in line with the decrease of chloro-content of the adsorbents from PVC to SP.The adsorptivity of PVC and CR was nearly equivalent to that of AC with their saturated adsorption being about 1.4 g-CHCl3 (g-absorbent) -1.For all adsorbents studied,the adsorption capacity always decreases with the increase of hydrochloric acid concentration.It is showed that the commercial polymer powder of PVC or CR can be used as an efficient absorbent for the removal of chloroform from its aqueous solution for its low cost,good adsorption ability and ease of thermal desorption for recycling.

  13. 盐酸消旋山莨菪碱在产程中的应用体会%Experience in the Application Hydrochloric Raceanisodamide during Childbirth

    Institute of Scientific and Technical Information of China (English)

    石爱辉; 舒敏; 张屏

    2013-01-01

    Objective To observe application ef ect of hydrochloric Raceanisodamide during childbirth. Methods:There are 512 cases of vaginal delivery without contraindications,which divided into A and B groups,each of 256 cases. During childbirth,primiparas of A group were injected slowly in the vein hydrochloride raceanisodamine 10mg,B group was injected 2% lidocaine in single point or multi-point of cervical edema.There are cervix time required, mode of childbirth, cervical laceration,postpartum hemorrhage,neonatal asphyxia and other projects to be compared. Results:A group with a short time,the cesarean section rate,cervical laceration rate,postpartum hemorrhage rate and neonatal asphyxia rate were significantly lower than group B. Conclusion:the active phase of cervical edema application hydrochloric Raceanisodamide can significantly shorten the active period,reduce the cesarean section rate,reduce the incidence of complications.%目的:观察产程中盐酸消旋山莨菪碱的应用效果。方法将512例无阴道分娩禁忌症的初产妇随机分为 A组和B组,各256例。在产程中A组给予盐酸消旋山莨菪碱10mg静脉缓慢注射,B组给予2%利多卡因宫颈水肿部位注射封闭或多点封闭。比较两组宫口开全所需时间、分娩方式、宫颈裂伤、产后出血、新生儿窒息率。结果 A组用时短,剖宫产率、宫颈裂伤、产后出血及新生儿窒息率明均显低于B组。结论产程活跃期发生宫颈水肿应用盐酸消旋山莨菪碱可明显缩短活跃期,降低剖宫产率、减少并发症的发生。

  14. Assessment of morphological changes and DNA quantification: An in vitro study on acid-immersed teeth

    Directory of Open Access Journals (Sweden)

    K Sowmya

    2013-01-01

    Full Text Available Context: Acid immersion of victim′s body is one of the methods employed to subvert identification of the victim, and hence of the perpetrator. Being hardest and chemically the most stable tissue in the body, teeth can be an important forensic investigative medium in both living and nonliving populations. Teeth are also good reservoirs of both cellular and mitochondrial DNA; however, the quality and quantity of DNA obtained varies according to the environment the tooth has been subjected to. DNA extraction from acid-treated teeth has seldom been reported. Aims: The objectives of the present study were to assess the morphological changes along with DNA recovery from acid-immersed teeth. Materials and Methods: Concentrated hydrochloric acid, nitric acid, and sulfuric acid were employed for tooth decalcification. DNA was extracted on an hourly basis using phenol-chloroform method. Quantification of extracted DNA was done using a spectrophotometer. Results: Results showed that hydrochloric acid had more destructive capacity compared to other acids. Conclusion: Sufficient quantity of DNA was obtainable till the first 2 hours of acid immersion and there was an inverse proportional relation between mean absorbance ratio and quantity of obtained DNA on an hourly basis.

  15. Effects of Inorganic acid catalysts on liquefaction of wood In phenol

    Institute of Scientific and Technical Information of China (English)

    Zhang Qiuhui; Zhao Guangjie; Chen Jinpeng

    2006-01-01

    In order to obtain the effects of acid catalysts on wood liquefaction in phenol, we investigated the liquefaction of wood powder from Chinese fir (Cunninghamia lanceolata) and poplar (Triploid Populus tomentosa Carr) in the presence of phenol with the following weak inorganic acids as catalysts: phosphoric acid (85%),sulfuric acid (36%),hydrochloric acid (37%)and oxalic acid (99.5%).Results show that phosphoric acid (85%) and sulfuric acid (36%) are better than the other catalysts.It was found that lower residue ratios can be obtained under defined reaction conditions: phenol/wood ratio is 4,a 10% catalyst based on the weight of phenol,a temperature of 150℃ for 2 h and phosphoric or sulfuric acid.The residue ratios are 3.2% and 4.0%,respectively.

  16. Lactic Acid Permeabilizes Gram-Negative Bacteria by Disrupting the Outer Membrane

    OpenAIRE

    Alakomi, H.-L.; Skyttä, E.; Saarela, M; Mattila-Sandholm, T.; Latva-Kala, K.; Helander, I M

    2000-01-01

    The effect of lactic acid on the outer membrane permeability of Escherichia coli O157:H7, Pseudomonas aeruginosa, and Salmonella enterica serovar Typhimurium was studied utilizing a fluorescent-probe uptake assay and sensitization to bacteriolysis. For control purposes, similar assays were performed with EDTA (a permeabilizer acting by chelation) and with hydrochloric acid, the latter at pH values corresponding to those yielded by lactic acid, and also in the presence of KCN. Already 5 mM (pH...

  17. Inhibition of Mild Steel Corrosion in Acidic Medium by Aqueous Extract of Tridax procumbens L.

    Directory of Open Access Journals (Sweden)

    G. Ilayaraja

    2011-01-01

    Full Text Available The inhibition efficiency (IE of an aqueous extract of Tridax procumbens L. in controlling corrosion of mild steel has been investigated by weight loss method in the absence and presence of corrosion inhibitor at different time interval at room temperature. The result showed that the corrosion inhibition efficiency of these compounds was found to vary with different time interval and different acid concentration. Also, it was found that the corrosion inhibition behavior of Tridax procumbens L. is greater in sulphuric acid than hydrochloric acid medium. So Tridax procumbens L. can be used as a good inhibitor for preventing mild steel material.

  18. Mathematical model formation of the process of deriving boric acid from ulexite mineral by full factorial design method

    OpenAIRE

    DURAK, Halil; GENEL, Yasar; BASHIROV, Novruz; KERIMOV, Genber

    2012-01-01

    Ulexite is a sodium calcium boron hydrate used in producing compounds, its chemical formula is Na2O2CaO5B2O3.16H2O, and it superabounds in Turkey. One of the significant boron compounds derived from boron minerals is boric acid. The aim of this study is producing boric acid in the wake of interaction of ulexite with hydrochloric acid solution, and offering an alternative process to producing boric acid by forming the mathematical model of this processing. F...

  19. Mathematical model formation of the process of deriving boric acid from ulexite mineral by full factorial design method

    OpenAIRE

    DURAK, Halil; GENEL, Yasar; BASHIROV, Novruz; KERIMOV, Genber

    2013-01-01

    Ulexite is a sodium calcium boron hydrate used in producing compounds, its chemical formula is Na2O2CaO5B2O3.16H2O, and it superabounds in Turkey. One of the significant boron compounds derived from boron minerals is boric acid. The aim of this study is producing boric acid in the wake of interaction of ulexite with hydrochloric acid solution, and offering an alternative process to producing boric acid by forming the mathematical model of this processing. Full factorial de...

  20. Synthesis and characterization of a novel temperature-pH responsive copolymer of 2-hydroxypropyl acrylate and aminoethyl methacrylate hydrochloric salt

    Directory of Open Access Journals (Sweden)

    2009-02-01

    Full Text Available In this investigation, a novel temperature-pH responsive copolymer was prepared by the radical copolymerization between 2-hydroxypropyl acrylate (HPA and aminoethyl methacrylate hydrochloric salt (AMHS. The molecular structure of the corresponding copolymer has been confirmed by 1H NMR and FTIR measurements. The results indicated that the lower critical solution temperature (LCST of the resulting copolymer has shown a considerable dependence on the monomer ratio and pH value in the medium. When the molar ratio of HPA to AMHS unit on polymer chain was fixed at 1.56, 2.25, and 3.01, the LCSTs of copolymers were observed at 36.5, 28.2 and 17.8°C, respectively. For the effect of additive salts, the LCST change of the copolymer was affected by both cations and anions in the following order of Al(NO33 > KNO3 > Mg(NO32 > NaNO3 and KCl ≈KSCN > KBr > KNO3 > KI. The copolymer seems to be useful as a candidate for the controlled-drug release carrier by pH and temperature external stimuli.

  1. Preparation of Highly Crystalline TiO2 Nanostructures by Acid-assisted Hydrothermal Treatment of Hexagonal-structured Nanocrystalline Titania/Cetyltrimethyammonium Bromide Nanoskeleton

    Directory of Open Access Journals (Sweden)

    Sakai Hideki

    2010-01-01

    Full Text Available Abstract Highly crystalline TiO2 nanostructures were prepared through a facile inorganic acid-assisted hydrothermal treatment of hexagonal-structured assemblies of nanocrystalline titiania templated by cetyltrimethylammonium bromide (Hex-ncTiO2/CTAB Nanoskeleton as starting materials. All samples were characterized by X-ray diffraction (XRD and transmission electron microscopy (TEM. The influence of hydrochloric acid concentration on the morphology, crystalline and the formation of the nanostructures were investigated. We found that the morphology and crystalline phase strongly depended on the hydrochloric acid concentrations. More importantly, crystalline phase was closely related to the morphology of TiO2 nanostructure. Nanoparticles were polycrystalline anatase phase, and aligned nanorods were single crystalline rutile phase. Possible formation mechanisms of TiO2 nanostructures with various crystalline phases and morphologies were proposed.

  2. Experimental study of the influence of acid wash on cellulose pyrolysis

    Institute of Scientific and Technical Information of China (English)

    WANG Shurong; LIAO Yanfen; LIU Qian; LUO Zhongyang; CEN Kefa

    2007-01-01

    The analysis of microstructure and polymerization degree showed that acid wash altered the cellulose morphology and decreased the polymerization degree significantly.A series of experiments were done to study the effect of acid wash on cellulose rapid pyrolysis.Experimental results showed that under acid pretreatment,the yield of biooil decreased while the production of gas and char increased.With an increase in acid concentration,this trend would be further enhanced.Sulphuric acid limited the formation of bio-oil more effectively than hydrochloric acid and phosphoric acid.According to the GC-MS analysis of bio-oil,high-concentration acid wash restrained the formation of levoglucosan by catalyzing dehydration process and cross linking reaction.

  3. A Comparative Study of Different Acids used for Sandstone Acid Stimulation: A Literature Review

    Science.gov (United States)

    Van Hong, Leong; Ben Mahmud, Hisham

    2017-07-01

    Matrix acidizing is an effective well stimulation technique, in which acids are injected at a pressure below the formation fracture pressure. The application of sandstone matrix acidizing has been widely used in the oil and gas industry for many decades. The application of mud acid, which is a combination of Hydrofluoric acid and Hydrochloric acid (HF:HCl) in well stimulation, has gained its popularity in improving the porosity and permeability of reservoir formation. In fact, this is driven by the effectiveness of HF in dissolving minerals in sandstone and HCl in controlling precipitation. Nonetheless, high temperature matrix acidizing approach is in growing need since many wells nowadays are producing from much deeper and hotter reservoir, with a temperature higher than 200°F. In such conditions, mud acid causes rapid reaction rates, hence becoming less efficient as the acids are consumed too early. Furthermore, mud acid is hazardous and very corrosive. On the contrary, previous studies had shown that Fluoroboric Acid (HBF4) and Phosphoric acid (H3PO4) offered numerous advantages in comparison to the conventional mud acid. HBF4 can hydrolyze to form HF whereas H3PO4 acts as a buffer acid; which is able to penetrate deeper into the formation before spending. Likewise, both acids cause more increase in the permeability, less change in the strength of core samples and significantly less corrosive. This paper had critically reviewed the experimental works which had been done on different types of acids. The advantages and disadvantages of these acids are evaluated. Therefore, a new acid combination (HBF4:H3PO4) is developed and the future work which can be done on it is proposed.

  4. Microscopic residues of bone from dissolving human remains in acids.

    Science.gov (United States)

    Vermeij, Erwin; Zoon, Peter; van Wijk, Mayonne; Gerretsen, Reza

    2015-05-01

    Dissolving bodies is a current method of disposing of human remains and has been practiced throughout the years. During the last decade in the Netherlands, two cases have emerged in which human remains were treated with acid. In the first case, the remains of a cremated body were treated with hydrofluoric acid. In the second case, two complete bodies were dissolved in a mixture of hydrochloric and sulfuric acid. In both cases, a great variety of evidence was collected at the scene of crime, part of which was embedded in resin, polished, and investigated using SEM/EDX. Apart from macroscopic findings like residual bone and artificial teeth, in both cases, distinct microscopic residues of bone were found as follows: (partly) digested bone, thin-walled structures, and recrystallized calcium phosphate. Although some may believe it is possible to dissolve a body in acid completely, at least some of these microscopic residues will always be found. © 2015 American Academy of Forensic Sciences.

  5. Photo-crosslinked hyaluronic acid coated upconverting nanoparticles

    Science.gov (United States)

    Mrazek, Jiri; Kettou, Sofiane; Matuska, Vit; Svozil, Vit; Huerta-Angeles, Gloria; Pospisilova, Martina; Nesporova, Kristina; Velebny, Vladimir

    2017-02-01

    Hyaluronic acid (HA)-coated inorganic nanoparticles display enhanced interaction with the CD44 receptors which are overexpressed in many types of cancer cells. Here, we describe a modification of core-shell β-NaY0.80Yb0.18Er0.02F4@NaYF4 nanoparticles (UCNP) by HA derivative bearing photo-reactive groups. UCNP capped with oleic acid were firstly transferred to aqueous phase by an improved protocol using hydrochloric acid or lactic acid treatment. Subsequently, HA bearing furanacryloyl moieties (HA-FU) was adsorbed on the nanoparticle surface and crosslinked by UV irradiation. The crosslinking resulted in stable HA coating, and no polymer desorption was observed. As-prepared UCNP@HA-FU show a hydrodynamic diameter of about 180 nm and are colloidally stable in water and cell culture media. The cellular uptake by normal human fibroblasts and MDA MB-231 cancer cell line was investigated by upconversion luminescence imaging.

  6. Drug: D04390 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D04390 Drug Dilute hydrochloric acid (JP16); Hydrochloric acid lemonade (JP16); Dil...ute hydrochloric acid (TN) Therapeutic category: 2335 ATC code: A09AB03 B05XA13 Hydrochloric acid [DR:D02057...nts D04390 Dilute hydrochloric acid (JP16); Hydrochloric acid lemonade (JP16) Anatomical Therapeutic Chemica...ESTIVES, INCL. ENZYMES A09AB Acid preparations A09AB03 Hydrochloric acid D04390 D...ilute hydrochloric acid (JP16); Hydrochloric acid lemonade (JP16) B BLOOD AND BLOOD FORMING ORGANS B05 BLOOD

  7. Effect of Thermal Treatment and Acid Leaching Process on Pore Characteristics of Nanometer Porous Glass

    Institute of Scientific and Technical Information of China (English)

    HAN Jianjun; XU Feng; LIU Jiandang; ZHAO Xiujian

    2007-01-01

    Porous glass was prepared by thermally treating sodium borosilicate glass for different time,the effect of thermal treatment on pore size distribution was discussed and the pore size of the prepared porous glass was measured by scanning electron microscopy (SEM) and differential thermal analysis (DTA). The results show that the optimum porous glass with an average diameter of 80 nm can be prepared by thermal treatment at 600 ℃ for 12 h and then acid treatment for 12 h in 2 mol· L-1 hydrochloric acid solution.

  8. [Interaction between NSAIDs and acetylsalicylic acid disregarded

    NARCIS (Netherlands)

    Vollaard, E.J.; Kramers, C.; Brouwers, J.R.B.J.

    2014-01-01

    In 2013 the European Medicines Agency declared that diclofenac is contraindicated in patients with arterial thrombotic complications, based on a meta-analysis of randomised controlled trials on the adverse reactions of NSAIDs. The same decision was taken for coxibs some years earlier. The Dutch auth

  9. Influence of acid leaching and calcination on iron removal of coal kaolin

    Institute of Scientific and Technical Information of China (English)

    Pei-wang Zhu; Wei-qiang Zeng; Xiu-lin Xu; Le-ming Cheng; Xiao Jiang; Zheng-lun Shi

    2014-01-01

    Calcination and acid leaching of coal kaolin were studied to determine an effective and economical preparation method of calcined kaolin. Thermogravimetric-differential thermal analysis (TG-DTA) and X-ray diffraction (XRD) demonstrated that 900°C was the suitable temperature for the calcination. Leaching tests showed that hydrochloric acid was more effective for iron dissolution from raw coal kaolin (RCK), whereas oxalic acid was more effective on iron dissolution from calcined coal kaolin (CCK). The iron dissolution from CCK was 28.78wt%, which is far less effective than the 54.86wt% of RCK under their respective optimal conditions. Through analysis by using Mössbauer spectroscopy, it is detected that nearly all of the structural ferrous ions in RCK were removed by hydrochloric acid. However, iron sites in CCK changed slightly by oxalic acid leaching because nearly all ferrous ions were transformed into ferric species after firing at 900°C. It can be concluded that it is difficult to remove the structural ferric ions and ferric oxides evolved from the structural ferrous ions. Thus, iron removal by acids should be conducted prior to calcination.

  10. 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.

  11. ACID RESISTANCE OF FLYASH BASED GEOPOLYMER MORTAR UNDER AMBIENT CURING AND HEAT CURING

    Directory of Open Access Journals (Sweden)

    V.Sreevidya

    2012-02-01

    Full Text Available An Experimental study was conducted to assess the Acid resistance of flyash based geopolymer mortar specimens of size 50x50x50mm with a ratio of flyash to sand as 1:3.The ratio between solution(Sodiumhydroxide and Sodium silicate solution to flyash were 0.376,0.386,0.396 and 0.416. After casting the specimens were subjected to both ambient curing and heat curing. In heat curing the specimens were kept continuously at 60oC for 24 hrs. Durability of specimens was assessed by immersing them in 5% of sulfuric acid and 5%hydrochloric acid for a period of 14 weeks. Evaluation of its resistance in terms of change in weight, compressive strength and visual appearance at regular intervals was carried out. After exposure in the acid solutions for 14 weeks, the samples showed very low weight loss. Results obtained from the present study indicate that Geopolymers are highly resistance to sulfuric acid and hydrochloric acid.

  12. Effect of acids on the teeth and its relevance in postmortem identification

    Directory of Open Access Journals (Sweden)

    Kiran Jadhav

    2009-01-01

    Full Text Available Background: The nature of crime is changing day by day and the forensic scientist is always facing new problems in the process of identification. For example, difficult though it may be to believe, criminals are now-a-days using acids to destroy bodies in order to avoid any personal identification. This is a matter of great interest to the forensic scientist. Is it possible to destroy the human body completely in an acid? If so, are there any means to identify the body? Objectives: The aim of this study was to identify the agent (acid that is most likely to be used in such crimes and to find out if the morphological changes in the teeth could be used to deduce the approximate duration of time elapsed after immersion of a body in an acid. Since the natural teeth are most resistant to destruction they can persist for long after other skeletal structures have been destroyed by physical agents. The objective of study was to observe the morphological changes occurring in natural human teeth when they were kept immersed in an acid solution. Materials and Methods: Teeth were kept in 25 ml of aqueous solutions of three different acids and observed periodically for morphological changes. Results: The results showed that teeth could be completely dissolved in 37% hydrochloric acid (HCl after 15 h of immersion, whereas in 65% nitric acid 20 h was required for complete dissolution. In the case of 96% sulphuric acid, the teeth reacted in a different manner. There was a residual precipitate observed at the bottom of the container after 144 h. It was possible to identify the characteristic morphological changes in the tooth until an advanced stage of degradation. Conclusion: Hydrochloric acid, nitric acid and sulfuric acid cause changes in the teeth and it is possible to deduce the approximate duration for which a body has been immersed in acid based on the charges observed.

  13. Effect of Acid Dissolution Conditions on Recovery of Valuable Metals from Used Plasma Display Panel Scrap

    Directory of Open Access Journals (Sweden)

    Kim Chan-Mi

    2017-06-01

    Full Text Available The objective of this particular study was to recover valuable metals from waste plasma display panels using high energy ball milling with subsequent acid dissolution. Dissolution of milled (PDP powder was studied in HCl, HNO3, and H2SO4 acidic solutions. The effects of dissolution acid, temperature, time, and PDP scrap powder to acid ratio on the leaching process were investigated and the most favorable conditions were found: (1 valuable metals (In, Ag, Mg were recovered from PDP powder in a mixture of concentrated hydrochloric acid (HCl:H2O = 50:50; (2 the optimal dissolution temperature and time for the valuable metals were found to be 60°C and 30 min, respectively; (3 the ideal PDP scrap powder to acid solution ratio was found to be 1:10. The proposed method was applied to the recovery of magnesium, silver, and indium with satisfactory results.

  14. Adsorption of uranyl ion on acid-modified zeolitic mineral clinoptilolite

    Directory of Open Access Journals (Sweden)

    Matijašević Srđan D.

    2009-01-01

    Full Text Available In this paper, the results of adsorption of uranyl ion on acid-modified zeolitic mineral clinoptilolite are presented. Adsorption was investigated at different amounts of solid phase in suspension, as well as at different pH values. The modified clinoptilolite samples were obtained by treatment of clinoptilolite with acids: hydrochloric, oxalyc and citric. Starting and modified clinoptilolites were characterized by chemical analysis, thermal (DT/TG analysis and by determination of cation exchange capacity, while starting and nonadsorbed amounts of uranyl ion were determined by fluorometric method. Uranyl ion adsorption experiments on natural unmodified zeolitic mineral showed that uranyl ion adsorption was low (29.2% and that treatment of clinoptilolite with acids significantly increases the adsorption of uranyl ion (>90%. In the case of acid treated clinoptilolites, the highest adsorption of uranyl ion was achieved on clinoptilolite modified with hydrochloric acid. Kinetics of adsorption showed that adsorption of uranyl ion begins very fast and that the most of uranyl ion was adsorbed in first 30 min. Practically, there were no changes in uranyl ion adsorption within next 72 h.

  15. Flame retardant wool using zirconium oxychloride in various acidic media optimized by RSM

    Energy Technology Data Exchange (ETDEWEB)

    Forouharshad, M., E-mail: Forouharmahdi@gmail.com [Textile Department, Islamic Azad University South Tehran Branch, Tehran (Iran, Islamic Republic of); Montazer, M., E-mail: tex5mm@aut.ac.ir [Textile Department, Center of Excellence, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Moghadam, M.B. [Department of Statistics, Allameh-Tabataba' i University, Tehran (Iran, Islamic Republic of); Saligheh, O. [Textile Department, Islamic Azad University South Tehran Branch, Young Researchers Club, Tehran (Iran, Islamic Republic of)

    2011-03-20

    Research highlights: {yields} We investigate effect of ZrOCl{sub 2} and HCl on the flame retardancy of wool fabric. {yields} The response surface methodology uses for the experimental plan with. {yields} The thermal degradation studies by thermal analysis, LOI and vertical flame test. {yields} The fabric surfaces observe by SEM. {yields} Results show an increase in the decomposition temperature, residual mass and LOI. - Abstract: The flame retardant wool was prepared using zirconium oxychloride with various acids. The thermal degradation of wool treated with the flame retardant synergistic system, zirconium oxychloride, citric acid and hydrochloric acid, was studied by thermal analysis, mass loss, limiting oxygen index (LOI) and vertical flame test. The fabric surfaces were also observed by SEM. The wool treated with the flame-retardant shows an increase in the decomposition temperature, residual mass and LOI. Also the wool treated with hydrochloric acid showed improved flame retardant properties compared to the use of formic acid. The response surface methodology (RSM) was also used for the experimental plan with four variables on the results of flame retardancy. The statistical analysis confirms the optimum conditions obtained by the experimental results.

  16. Lactic acid permeabilizes gram-negative bacteria by disrupting the outer membrane.

    Science.gov (United States)

    Alakomi, H L; Skyttä, E; Saarela, M; Mattila-Sandholm, T; Latva-Kala, K; Helander, I M

    2000-05-01

    The effect of lactic acid on the outer membrane permeability of Escherichia coli O157:H7, Pseudomonas aeruginosa, and Salmonella enterica serovar Typhimurium was studied utilizing a fluorescent-probe uptake assay and sensitization to bacteriolysis. For control purposes, similar assays were performed with EDTA (a permeabilizer acting by chelation) and with hydrochloric acid, the latter at pH values corresponding to those yielded by lactic acid, and also in the presence of KCN. Already 5 mM (pH 4.0) lactic acid caused prominent permeabilization in each species, the effect in the fluorescence assay being stronger than that of EDTA or HCl. Similar results were obtained in the presence of KCN, except for P. aeruginosa, for which an increase in the effect of HCl was observed in the presence of KCN. The permeabilization by lactic and hydrochloric acid was partly abolished by MgCl(2). Lactic acid sensitized E. coli and serovar Typhimurium to the lytic action of sodium dodecyl sulfate (SDS) more efficiently than did HCl, whereas both acids sensitized P. aeruginosa to SDS and to Triton X-100. P. aeruginosa was effectively sensitized to lysozyme by lactic acid and by HCl. Considerable proportions of lipopolysaccharide were liberated from serovar Typhimurium by these acids; analysis of liberated material by electrophoresis and by fatty acid analysis showed that lactic acid was more active than EDTA or HCl in liberating lipopolysaccharide from the outer membrane. Thus, lactic acid, in addition to its antimicrobial property due to the lowering of the pH, also functions as a permeabilizer of the gram-negative bacterial outer membrane and may act as a potentiator of the effects of other antimicrobial substances.

  17. Role of potassium in acid secretion

    Institute of Scientific and Technical Information of China (English)

    John P Geibel

    2005-01-01

    Potassium (K+) ions are critical for the activation and catalytic cycle of the gastric H+,K+-ATPase, resulting in the secretion of hydrochloric acid into the parietal cell canaliculus. As both symptom, severity and esophageal mucosal damage in gastro-esophageal reflux disease (GERD) are related to the degree of acid exposure, K+ is a logical target for approaches to inhibit acid production.The probable K+ binding site on the gastric H+,K+-ATPase has recently been described and studies are elucidating how K+ activates the enzyme. K+ channels in the apical membrane of the parietal cell are implicated in the recycling of K+ and, to date, three potential K+ channels (KCNQ1, Kir2.1 and Kir4.1) have been identified. The channels represent theoretical sites for agents to control acid secretion but it will be difficult to develop selective blockers. An alternative strategy is to prevent K+ from activating gastric H+,K+-ATPase; the potassiumcompetitive acid blocker (P-CAB) class inhibits acidsecretion by binding at or near the K+ binding site.Ongoing research is further defining the role of K+ in the functioning of the gastric H+,K+-ATPase, as well as determining the clinical utility of agents directed toward this important cation.

  18. Are teeth evidence in acid environment

    Directory of Open Access Journals (Sweden)

    Makesh Raj

    2013-01-01

    Full Text Available Aim: Teeth are the most durable structures that resist destruction more than skeletal tissue Commercially available acids can be used to destroy the body or a part, to mask human identification. The present study examines the effect of caustic acids on human dentition. Materials and Methods: Ten upper anterior teeth each were immersed in 37% hydrochloric acid (conc. HCl, 65% nitric acid (conc. HNO 3 and 96% sulfuric acid (conc. H 2 SO 4 . Teeth were retrieved, washed in distilled water, dried, photographed and radiographed at intervals of 15 min, 30 min, 1 hr, 3 hr, 5 hr and 8 hr. Results: Teeth placed in conc. HCl and conc. HNO 3 dissolved completely after 8 hours, while that placed in conc. H 2 SO 4 retained its morphology and radiographic dimension even after 8 hours. Conclusion: Hence teeth can serve as a tool in identification (age estimation and sex determination of the victim when in contact with conc. H 2 SO 4 .

  19. Reactivities of acid and/or tetralin pretreated Wandoan coal for a Curie point flash pyrolysis; Sanzen shori, tetralin yobaimae shori Wandoan tan no kyusoku netsubunkai

    Energy Technology Data Exchange (ETDEWEB)

    Kishino, M.; Sakanishi, K.; Korai, Y.; Mochida, I. [Kyushu University, Fukuoka (Japan). Institute of Advanced Material Study

    1996-10-28

    Discussions were given on effects of acid pretreatment and tetralin swelling in Wandoan coal on a Curie point flash pyrolysis (which used a Curie point pyrolyzer). Residue yield loss effects were obtained at 3.9% in hydrochloric acid pretreatment, and 6.2% in acetic acid pretreatment. The effects of tetralin swelling pretreatment were compared in the similar manner in terms of the residue yield loss. The effects were 4.0% in untreated coal, 2.0% in the hydrochloric acid pretreatment, and 0.6% in the acetic acid pretreatment. It is thought that components that can be activated by acetic acid have already been activated, but the remaining components would not be activated by tetralin. Average microporosity (area) in the remaining particle as a whole shows very little difference both in acetic acid pretreated coal and untreated coal. However, with the acetic acid pretreatment, pores smaller than 4{mu}m{sup 2} disappeared, and pores as large as 205 to 411{mu}m{sup 2} increased largely. This phenomenon was observed as an increase in foaming degree under microscopic observation, even if the average microporosity remains equal. Thermoplasticity of the coal increased, and so did volatilization reactivity as a result of the acetic acid pretreatment, resulting in appearance of a large number of large pores. 6 refs., 2 figs., 2 tabs.

  20. Effect of Ammonium- and Phosphonium-Based Ionic Liquids on the Separation of Lactic Acid by Supported Ionic Liquid Membranes (SILMs).

    Science.gov (United States)

    Matsumoto, Michiaki; Panigrahi, Abhishek; Murakami, Yuuki; Kondo, Kazuo

    2011-05-13

    Biodegradable polymers have attracted much attention from an environmental point of view. Optically pure lactic acid that can be prepared by fermentation is one of the important raw materials for biodegradable polymer. The separation and purification of lactic acid from the fermentation broth are the major portions of the production costs. We proposed the application of supported ionic liquid membranes to recovering lactic acid. In this paper, the effect of ionic liquids, such as Aliquat 336, CYPHOS IL-101, CYPHOS IL-102, CYPHOS IL-104, CYPHOS IL-109 and CYPHOS IL-111 on the lactic acid permeation have been studied. Aliquat 336, CYPHOS IL-101 and CYPHOS IL-102 were found to be the best membrane solvents as far as membrane stability and permeation of lactic acid are concerned. CYPHOS IL-109 and CYPHOS IL-111 were found to be unsuitable, as they leak out from the pores of the supported liquid membrane (SLM), thereby allowing free transport of lactic acid as well as hydrochloric acid. CYPHOS IL-102 was found to be the most adequate (Permeation rate = 60.41%) among these ionic liquids as far as the separation of lactic acid is concerned. The permeation mechanisms, by which ionic liquid-water complexes act as the carrier of lactate and hydrochloric acid, were proposed. The experimental permeation results have been obtained as opposed to the expected values from the solution-diffusion mechanism.

  1. Effect of Ammonium- and Phosphonium-Based Ionic Liquids on the Separation of Lactic Acid by Supported Ionic Liquid Membranes (SILMs

    Directory of Open Access Journals (Sweden)

    Kazuo Kondo

    2011-05-01

    Full Text Available Biodegradable polymers have attracted much attention from an environmental point of view. Optically pure lactic acid that can be prepared by fermentation is one of the important raw materials for biodegradable polymer. The separation and purification of lactic acid from the fermentation broth are the major portions of the production costs. We proposed the application of supported ionic liquid membranes to recovering lactic acid. In this paper, the effect of ionic liquids, such as Aliquat 336, CYPHOS IL-101, CYPHOS IL-102, CYPHOS IL-104, CYPHOS IL-109 and CYPHOS IL-111 on the lactic acid permeation have been studied. Aliquat 336, CYPHOS IL-101 and CYPHOS IL-102 were found to be the best membrane solvents as far as membrane stability and permeation of lactic acid are concerned. CYPHOS IL-109 and CYPHOS IL-111 were found to be unsuitable, as they leak out from the pores of the supported liquid membrane (SLM, thereby allowing free transport of lactic acid as well as hydrochloric acid. CYPHOS IL-102 was found to be the most adequate (Permeation rate = 60.41% among these ionic liquids as far as the separation of lactic acid is concerned. The permeation mechanisms, by which ionic liquid-water complexes act as the carrier of lactate and hydrochloric acid, were proposed. The experimental permeation results have been obtained as opposed to the expected values from the solution-diffusion mechanism.

  2. Quartz crystal microbalance and spectroscopy measurements for acid doping in polyaniline films

    Directory of Open Access Journals (Sweden)

    Mohamad M Ayad and Eman A Zaki

    2008-01-01

    Full Text Available We investigated the doping of thin polyaniline (PANI films, prepared by the chemical oxidation of aniline, with different acids. The initial step in the investigation is the preparation of PANI films from aqueous hydrochloric acid solution. This is followed by dedoping with ammonia to obtain a PANI base, which is subsequently doped with strong acids (e.g. hydrochloric, sulfuric, phosphoric and trichloroacetic acids and with a weak acid (acetic acid. The dopant weight fraction (w, which is connected with the gain of mass during the doping of PANI, was determined in situ using a quartz crystal microbalance (QCM. The behavior of PANI upon doping with different anions derived from strong acids indicates that both proton and the anion uptake into the polymer chains occur sharply, rapidly, completely, and reversibly. However the uptake in the case in acetic acid is characterized by slow diffusion. The doping was studied at different concentrations of acetic acid. A second cycle of dedoping–redoping was also performed. The kinetics of the doping reaction is dominated by Fickian diffusion kinetics. The diffusion coefficients (D of the dopant ions into the PANI chains were determined using the QCM and by UV–Vis absorption spectroscopy in the range of (0.076–1.64× 10−15 cm2 s−1. It was found that D in the second cycle of doping is larger than that evaluated from the first cycle of doping for high concentrations of acetic acid. D for the diffusion and for the dopant ion expulsion from the PANI chains was also determined during the redoping process. It was found that D for acetic acid ions in the doping process is larger than that calculated for the dedoping process.

  3. Recovery of calcium carbonate from steelmaking slag and utilization for acid mine drainage pre-treatment.

    Science.gov (United States)

    Mulopo, J; Mashego, M; Zvimba, J N

    2012-01-01

    The conversion of steelmaking slag (a waste product of the steelmaking process) to calcium carbonate (CaCO(3)) was tested using hydrochloric acid, ammonium hydroxide and carbon dioxide via a pH-swing process. Batch reactors were used to assess the technical feasibility of calcium carbonate recovery and its use for pre-treatment of acid mine drainage (AMD) from coal mines. The effects of key process parameters, such as the amount of acid (HCl/calcium molar ratio), the pH and the CO(2) flow rate were considered. It was observed that calcium extraction from steelmaking slag significantly increased with an increase in the amount of hydrochloric acid. The CO(2) flow rate also had a positive effect on the carbonation reaction rate but did not affect the morphology of the calcium carbonate produced for values less than 2 L/min. The CaCO(3) recovered from the bench scale batch reactor demonstrated effective neutralization ability during AMD pre-treatment compared with the commercial laboratory grade CaCO(3).

  4. 含氢氟酸和盐酸的混合酸的回收利用方法%Technologies of Recycling the Mixture Composed of Hydrofluoric acid and Hydrochloric acid

    Institute of Scientific and Technical Information of China (English)

    张丽红

    2010-01-01

    简要综述了含氢氟酸和盐酸的混合酸回收利用方法.分别介绍了用含氢氟酸和盐酸的混合酸生产氟化钙、氟化镁、氟化锂、氟化氢钠和氟硅酸钾,同时产生盐酸或氯化物的方法.得到的产品质量好、成本低,对氟资源的综合利用和环境保护具有积极意义.

  5. Synthesis and Performance of Mannich Base Quaternary Ammonium Salt Acidizing Corrosion Inhibitor%曼尼希碱季铵盐酸化缓蚀剂的合成及性能

    Institute of Scientific and Technical Information of China (English)

    赵顺强; 孙永涛; 马增华; 付朝阳

    2014-01-01

    合成了一种新型的曼尼希碱季铵盐(BMQA)酸化缓蚀剂,通过静态失重法测试了缓蚀剂在不同浓度盐酸中的缓蚀性能。结果表明,90℃下,缓蚀剂 BMQA 在15%盐酸中加入0.1%,18%盐酸中加入0.2%,28%盐酸中加入0.5%,N80钢的腐蚀速率都能小于4 g·m-2·h-1。极化曲线测试表明该缓蚀剂是抑制阳极为主的混合型缓蚀剂,遵循 Langmuir 吸附等温式,能自发在金属表面进行化学吸附。%A new type of Mannich base quaternary ammonium salt was synthesized as an acidification corrosion inhibitor.The inhibition performance of this corrosion inhibitor was evaluated in hydrochloric acid with different concentrations by static weight loss method.The results showed that with 0.1% inhibitor in 15% hydrochloric acid, 0.2% inhibitor in 18% hydrochloric acid and 0.5% inhibitor in 28% hydrochloric acid,the corrosion rates of steel N80 were all lower than 4 g·m-2 ·h-1 at 90℃.Polarization curves indicate that the corrosion inhibitor is a mixed inhibitor but mainly prohibits the anodic corrosion process,obeys the Langmuir adsorption isothermal equation and can spontaneously absorb on the steel surface by chemisorption.

  6. Chemical polymerization of aniline in phenylphosphinic acid

    Directory of Open Access Journals (Sweden)

    NICOLETA PLESU

    2005-10-01

    Full Text Available The chemical polymerization of aniline was performed in phenylphosphinic acid (APP medium using ammonium peroxidisulfate as the oxidizing agent, at 0 ºC and 25 ºC. The yield of polyaniline (PANI was about 60–69 %. The polymerization process required an induction time 8–10 times greater than in other acids (hydrochloric, sulfuric. The average density of the obtained polymer was 1.395 g cm-3 for PANI-salt and 1.203 g cm-3 for PANI-base. The acid capacity of PANI depends on the synthesis parameters and the maximum value was 15.02 meq/g polymer. The inherent viscosity of PANI was 0.662 dl/g at aniline/oxidant molar ratios >2 and 0 ºC. The oxidation state was a function of the synthesis parameters and lay between 0.553–0.625, as determined from UV-VIS and titration with TiCl3 data. The PANI samples were characterized by measurements of their density, inherent viscosity, conductivity, acid capacity, FTIR and UV-VIS spectrum, and thermogravimetric data.

  7. Corrosion Inhibition and Adsorption Behavior of Clove Oil on Iron in Acidic Medium

    Directory of Open Access Journals (Sweden)

    Archana Saxena

    2012-01-01

    Full Text Available Corrosion behavior of iron in hydrochloric acid solution was studied using weight loss as well Scanning electron microscopy study without and with clove oil. The percentage inhibition efficiency increases with increasing clove oil concentration. All the data revel that the oil acts as an excellent inhibitor for the corrosion of iron in HCl solution. Thermodynamic, kinetic parameters and equilibrium constant for adsorption process were calculated from the experimental data. The adsorption of clove oil on experimental metals was found to follow the Langmuir adsorption isotherm at all the concentration studies. Scanning electron microscope (SEM, investigations also indicate that clove oil greatly lowers the dissolution currents.

  8. Inhibiting Effects of Rabeprazole Sulfide on the Corrosion of Mild Steel in Acidic Chloride Solution

    Directory of Open Access Journals (Sweden)

    M. K. Pavithra

    2013-01-01

    Full Text Available The corrosion inhibition effect of Rabeprazole sulfide (RS on mild steel in 1 M hydrochloric acid (HCl was investigated using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS, and chronoamperometric measurements. Protection efficiency of RS increases with the concentration and decreases with the rise in temperature. Adsorption of RS on mild steel surface in 1 M HCl follows Langmuir adsorption isotherm. The kinetic and thermodynamic parameters governing the adsorption process were calculated and discussed. The polarization results suggest that RS performed as an excellent mixed-type inhibitor for mild steel corrosion in 1 M HCl.

  9. Lactic-acid stress causes vacuolar fragmentation and impairs intracellular amino-acid homeostasis in Saccharomyces cerevisiae.

    Science.gov (United States)

    Suzuki, Toshihiro; Sugiyama, Minetaka; Wakazono, Kenta; Kaneko, Yoshinobu; Harashima, Satoshi

    2012-04-01

    To gain more insight into adaptation response to lactic-acid stress in yeast, a genome-wide screening for genes whose disruption caused hypersensitivity to 4.0% l-lactic acid (pH 2.8) was performed using the gene deletion collection of Saccharomyces cerevisiae. We identified 107 genes that contributed significantly to the ability of yeast cells to adapt lactic-acid stress. More than 30% of the genes identified in this screening were newly identified to be involved in mechanisms for adaptation response to lactic acid. We found that protein urmylation by Uba4 and N-terminal acetylation by Nat3 were involved in lactic acid adaptation mechanisms. Functional categorization of the genes followed by microscopic analysis revealed that a variety of cellular functions were involved in adaptation response to lactic acid and function associated with vacuolar transport played important roles in adaptation response to lactic acid. We also found that vacuole fragmented immediately upon exposure to lactic- and hydrochloric-acid stress. In addition, our analysis revealed that lactic-acid stress significantly reduced the amount of intracellular amino acids. Amino acid supplementation recovered the adaptation deficiency to lactic acid, suggesting that intracellular amino-acid homeostasis plays important roles in adaptation response to lactic-acid stress. These data suggest that enhancing vacuolar integrity, as well as maintaining intracellular amino-acid homeostasis may be an efficient approach to confer resistance to lactic-acid stress. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  10. Electrochemical and XPS studies of decylamides of {alpha}-amino acids adsorption on carbon steel in acidic environment

    Energy Technology Data Exchange (ETDEWEB)

    Olivares, O. [Programa de Ingenieria Molecular, Competencia de Quimica Aplicada, Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas No. 152, San Bartolo Atepehuacan, Mexico 07730, DF (Mexico); Instituto Politecnico Nacional-ESIQIE, Departamento de Ingenieria de Materiales y Metalurgia, Apdo. Postal 75-874, Mexico 07300, DF (Mexico); Likhanova, N.V. [Programa de Ingenieria Molecular, Competencia de Quimica Aplicada, Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas No. 152, San Bartolo Atepehuacan, Mexico 07730, DF (Mexico)]. E-mail: nvictoro@imp.mx; Gomez, B. [Programa de Ingenieria Molecular, Competencia de Quimica Aplicada, Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas No. 152, San Bartolo Atepehuacan, Mexico 07730, DF (Mexico); Navarrete, J. [Programa de Ingenieria Molecular, Competencia de Quimica Aplicada, Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas No. 152, San Bartolo Atepehuacan, Mexico 07730, DF (Mexico); Llanos-Serrano, M.E. [Programa de Ingenieria Molecular, Competencia de Quimica Aplicada, Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas No. 152, San Bartolo Atepehuacan, Mexico 07730, DF (Mexico); Arce, E. [Instituto Politecnico Nacional-ESIQIE, Departamento de Ingenieria de Materiales y Metalurgia, Apdo. Postal 75-874, Mexico 07300, DF (Mexico); Hallen, J.M. [Instituto Politecnico Nacional-ESIQIE, Departamento de Ingenieria de Materiales y Metalurgia, Apdo. Postal 75-874, Mexico 07300, DF (Mexico)

    2006-02-15

    Corrosion inhibition of steel in hydrochloric acid by decylamides of {alpha}-amino acids derivatives was studied using gravimetric and electrochemical techniques. Protection efficiencies of 90% were obtained with 100 ppm of tyrosine and glycine derivatives, while alanine and valine derivatives reached only 80%. The order of increasing inhibition efficiency was correlated with the modification of the molecular structure of inhibitors. Potentiodynamic polarization curves indicated that both the decylamide of tyrosine and glycine acted primarily as anodic type inhibitors, whereas the decylamide of alanine and valine were of the cathodic type. Thermodynamic parameters and Flory-Huggins adsorption isotherms described the experimental findings. The number of active sites, equilibrium constant, enthalpy and change of free energy were computed for all inhibitors studied. This information suggested that organic molecules were adsorbed and displaced water molecules from the steel surface. X-ray photoelectron spectroscopy confirmed that species of N, C and O interacted with steel to form a continuous protective film.

  11. Effect of strong acids on red mud structural and fluoride adsorption properties.

    Science.gov (United States)

    Liang, Wentao; Couperthwaite, Sara J; Kaur, Gurkiran; Yan, Cheng; Johnstone, Dean W; Millar, Graeme J

    2014-06-01

    The removal of fluoride using red mud has been improved by acidifying red mud with hydrochloric, nitric and sulphuric acid. The acidification of red mud causes sodalite and cancrinite phases to dissociate, confirmed by the release of sodium and aluminium into solution as well as the disappearance of sodalite bands and peaks in infrared and X-ray diffraction data. The dissolution of these mineral phases increases the amount of available iron and aluminium oxide/hydroxide sites that are accessible for the adsorption of fluoride. However, concentrated acids have a negative effect on adsorption due to the dissolution of these iron and aluminium oxide/hydroxide sites. The removal of fluoride is dependent on the charge of iron and aluminium oxide/hydroxides on the surface of red mud. Acidifying red mud with hydrochloric, nitric and sulphuric acid resulted in surface sites of the form ≡SOH2(+) and ≡SOH. Optimum removal is obtained when the majority of surface sites are in the form ≡SOH2(+) as the substitution of a fluoride ion does not cause a significant increase in pH. This investigation shows the importance of having a low and consistent pH for the removal of fluoride from aqueous solutions using red mud.

  12. Drug: D02057 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D02057 Drug Hydrochloric acid (JP16/NF) HCl 35.9767 36.4609 D02057.gif Pharmaceutic... Miscellaneous 7190 Miscellaneous D02057 Hydrochloric acid (JP16/NF) Anatomical T.... ENZYMES A09A DIGESTIVES, INCL. ENZYMES A09AB Acid preparations A09AB03 Hydrochloric acid D02057 Hydrochloric...USION SOLUTIONS B05X I.V. SOLUTION ADDITIVES B05XA Electrolyte solutions B05XA13 Hydrochloric acid D02057 Hydrochloric

  13. Research on Direct and Accurate Titration of Strong Acid Strong-Weak Acid Mixture%强酸-弱酸混合体系中准确滴定强酸的研究

    Institute of Scientific and Technical Information of China (English)

    马荔; 张卫; 陈虹锦; 梁竹梅; 谢少艾; 李梅

    2011-01-01

    In order to gain accurately the concentration of the strong acid in strong-weak acid mixture by acid-base titration ,the concentration of the weak acid in the mixture need to be considered at different accuracy demand condition.Based on the analysis of the two sources of the end point error(TE) in the titration process, this article proposed a new method of calculating the end point error in the mixture by acid-base titration. It calculated the concentration range demands of acetate acid and hexamethylenetetramine in hydrochloric acid-acetate acid mixture and hydrochloric acid-hexamethylenetetramine acid mixture respectively at the different appointed TE demands and strong acid concentration ranges. Along with the increasing pH values of change color point of the acid-base indicators, the upper limits of the two weak acid concentrations are decreasing gradually. When the concentrations of acetate acid and hexamethylenetetramine are lower than 1. 18 and 0. 135 mmol/dm3 respectively at the | TE| = 1% demand, the hydrochloric acid content in 0.1 mol/dm3 concentration range can be titrated accurately by using any acidic acid-base indicator. As the concentrations of the two weak acids are lower than 10.6 and 10.5 mmol/dm3 respectively at the same TE demand ,the hydrochloric acid content in 1.0 mol/dm3 concentration range can be titrated accurately by using any acidic acid-base indicator.%为准确滴定出强酸-弱酸混合体系中所含强酸的量,需考虑在不同的准确度要求条件下,混合酸体系中弱酸的浓度范围要求.基于混合酸滴定过程终点误差的2个来源分析,提出了混合酸体系中终点误差(TE)计算的新方法.在指定的终点误差要求和强酸的浓度范围条件下,计算了HCl-HAe、HCl-六次甲基四胺盐两种混合酸体系中HAc、六次甲基四胺盐浓度范围要求,随着各酸碱指示剂变色点pH值的增大,两弱酸浓度的上限要求逐渐减小.在lTEl=1%条件下,当HAc、六次甲

  14. 普瑞巴林联合盐酸羟考酮治疗癌性神经病理痛33例%Therapeutic Effects of Pregabalin Combined with Hydrochloric Oxycodone on 33 Casesof Malignant Neuropathic Pain

    Institute of Scientific and Technical Information of China (English)

    章必成; 章志怀; 王俊; 王志刚; 吴婷婷; 饶智国; 高建飞

    2015-01-01

    Objective To evaluate the effects of pregabalin combined with hydrochloric oxycodone on patients with ma-lignant neuropathic pain (MNP). Methods A total of 66 patients with MNP was divided into control group or treatment group randomly. The patients in control group received only hydrochloric oxycodone, and treatment group were treated with the combina-tion of pregabalin and hydrochloric oxycodone. Numeric rating scale (NRS) score was used to evaluate the analgesic effects. Med-ical outcomes study sleep scale (MOS-SS,Chinese version) was used to evaluate the improvement of sleep disorder. The changes of depression or anxiety were investigated by 17-item Hamilton Depression Rating Scale (HAMD-17) or Hamilton Anxiety Scale (HAMA), respectively. Side effects were accessed by Acute and Subacute Toxicity Grading Criteria of Anticancer Drugs (WHO). Results The pain control rate of treatment group was 87. 1% , which was superior to that of control group (58. 6% ) (P<0. 05). The improvement of sleep interference, and the quality and quantity of sleep in treatment group were also superior to that in control group (P<0. 05). After the treatment, depression and anxiety was attenuated in both groups, and the improvement degree in treatment group was higher than that in control group (P<0. 05). No obvious side effects were found in either groups. Conclusion The combination therapy of pregabalin and hydrochloric oxycodone is the better way to treat MNP.%目的:评价普瑞巴林联合盐酸羟考酮治疗癌性神经病理痛(MNP)的疗效。方法将66例 MNP 患者随机分为两组各33例,对照组接受盐酸羟考酮治疗,治疗组接受盐酸羟考酮+普瑞巴林治疗。采用数字评估法(NRS)评分比较两组患者的止痛效果,采用 MOS-SS 睡眠量表(中文版)评价和比较两组患者的睡眠改善情况,采用17项汉密尔顿抑郁量表(HAMD-17)及汉密尔顿焦虑量表(HAMA)分别评定和比较两组患者的抑郁、焦虑状态,按

  15. Single-stranded regions in transforming deoxyribonucleic acid after uptake by competent Haemophilus influenzae

    Energy Technology Data Exchange (ETDEWEB)

    Sedgwick, B.; Setlow, J.K.

    1976-02-01

    About 15% of donor deoxyribonucleic acid (DNA) is single stranded immediately after uptake into competent Haemophilus influenzae wild-type cells, as judged by its sensitivity to S1 endonuclease. This amount decreases to 4 to 5% by 30 min after uptake. Mutants which are defective in the covalent association of recipient and donor DNA form little or no S1 endonuclease-sensitive donor. At 17 C donor DNA taken up by the wild type contains single-stranded regions although there is no observable association, either covalent or noncovalent. The single-stranded regions are at the ends of donor DNA molecules, as judged by the unchanged sedimentation velocity after S1 endonuclease digestion. The amount of single-stranded donor remains constant at 17 C for more than 60 min after uptake, suggesting that the decrease observed at 37 C is the result of association of single-stranded ends with single-stranded regions of recipient cell DNA. Three sequential steps necessary for the integration of donor DNA into recipient DNA are proposed: the synthesis of single-stranded regions in recipient DNA, the interaction of donor DNA with recipient DNA resulting in the production of single-stranded ends on donor DNA, and the stable pairing of homologous single-stranded regions. (auth)

  16. Solution of rocks and refractory minerals by acids at high temperatures and pressures. Determination of silica after decomposition with hydrofluoric acid

    Science.gov (United States)

    May, I.; Rowe, J.J.

    1965-01-01

    A modified Morey bomb was designed which contains a removable nichromecased 3.5-ml platinium crucible. This bomb is particularly useful for decompositions of refractory samples for micro- and semimicro-analysis. Temperatures of 400-450?? and pressures estimated as great as 6000 p.s.i. were maintained in the bomb for periods as long as 24 h. Complete decompositions of rocks, garnet, beryl, chrysoberyl, phenacite, sapphirine, and kyanite were obtained with hydrofluoric acid or a mixture of hydrofluoric and sulfuric acids; the decomposition of chrome refractory was made with hydrochloric acid. Aluminum-rich samples formed difficultly soluble aluminum fluoride precipitates. Because no volatilization losses occur, silica can be determined on sample solutions by a molybdenum-blue procedure using aluminum(III) to complex interfering fluoride. ?? 1965.

  17. Ethanol and xylitol production by fermentation of acid hydrolysate from olive pruning with Candida tropicalis NBRC 0618.

    Science.gov (United States)

    Mateo, Soledad; Puentes, Juan G; Moya, Alberto J; Sánchez, Sebastián

    2015-08-01

    Olive tree pruning biomass has been pretreated with pressurized steam, hydrolysed with hydrochloric acid, conditioned and afterwards fermented using the non-traditional yeast Candida tropicalis NBRC 0618. The main aim of this study was to analyse the influence of acid concentration on the hydrolysis process and its effect on the subsequent fermentation to produce ethanol and xylitol. From the results, it could be deduced that both total sugars and d-glucose recovery were enhanced by increasing the acid concentration tested; almost the whole hemicellulose fraction was hydrolysed when 3.77% was used. It has been observed a sequential production first of ethanol, from d-glucose, and then xylitol from d-xylose. The overall ethanol and xylitol yields ranged from 0.27 to 0.38kgkg(-1), and 0.12 to 0.23kgkg(-1) respectively, reaching the highest values in the fermentation of the hydrolysates obtained with hydrochloric acid 2.61% and 1.11%, respectively.

  18. Selection of refractory materials for acid tanks at the CSN continuous pickling line; Selecao de materiais refratarios para tanques de acido das linhas de decapagem continua da CSN

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Sidiney Nascimento; Marques, Oscar Rosa; Bueno, Mauricio Chaves [Companhia Siderurgica Nacional, Volta Redonda, RJ (Brazil); Longo, Elson; Silva Pinheiro, Adriano da [Sao Carlos Univ., SP (Brazil). Dept. de Quimica

    1997-12-31

    Aiming at the revamping of the CSN continuous pickling line 4 acid tanks, a Post Mortem study of the refractory lining was carried out. The collected samples were characterized through techniques such as chemical analysis, mercury porosimetry, X-ray diffraction and scanning electronic microscopy. Trying to reproduce the operational conditions closely, laboratorial simulations were carried out. Such simulations lead to the addition of some alterations on the test method proposed by ABNT. Primarily, the sulfuric acid was substituted by hydrochloric acid (30%), containing iron in solution (130g/l). As result, it was concluded that acid resistant refractories containing a smaller alumina and /or corundum and mullite concentrations, presenting a smaller open porosity and average pore diameter, have a better performance face to corrosion due to hydrochloric acid solution. In addition, abrasion wear resistance tests, according to the ASTM-G65-85 standard were carried out in order to select different materials to the acid tanks cells. (author) 3 refs., 5 figs., 12 tabs.

  19. Improving clarity and stability of skim milk powder dispersions by dissociation of casein micelles at pH 11.0 and acidification with citric acid.

    Science.gov (United States)

    Pan, Kang; Zhong, Qixin

    2013-09-25

    Casein micelles in milk cause turbidity and have poor stability at acidic conditions. In this study, skim milk powder dispersions were alkalized to pH 10.0 or 11.0, corresponding to reduced particle mass. In the following acidification with hydrochloric or citric acid, the re-formation of casein particles was observed. The combination of treatment at pH 11.0 and acidification with citric acid resulted in dispersions with the lowest turbidity and smallest particles, which enabled translucent dispersions at pH 5.5-7.0, corresponding to discrete nanoparticles. The concentration of ionic calcium was lower when acidified with citric acid than hydrochloric acid, corresponding to smaller particles with less negative zeta potential. The pH 11.0 treatment followed by acidification with citric acid also resulted in smaller particles than the simple chelating effects (directly implementing sodium citrate). The produced casein nanoparticles with reduced dimensions can be used for beverage and other novel applications.

  20. A hydrometallurgical process for the recovery of terbium from fluorescent lamps: Experimental design, optimization of acid leaching process and process analysis.

    Science.gov (United States)

    Innocenzi, Valentina; Ippolito, Nicolò Maria; De Michelis, Ida; Medici, Franco; Vegliò, Francesco

    2016-12-15

    Terbium and rare earths recovery from fluorescent powders of exhausted lamps by acid leaching with hydrochloric acid was the objective of this study. In order to investigate the factors affecting leaching a series of experiments was performed in according to a full factorial plan with four variables and two levels (4(2)). The factors studied were temperature, concentration of acid, pulp density and leaching time. Experimental conditions of terbium dissolution were optimized by statistical analysis. The results showed that temperature and pulp density were significant with a positive and negative effect, respectively. The empirical mathematical model deducted by experimental data demonstrated that terbium content was completely dissolved under the following conditions: 90 °C, 2 M hydrochloric acid and 5% of pulp density; while when the pulp density was 15% an extraction of 83% could be obtained at 90 °C and 5 M hydrochloric acid. Finally a flow sheet for the recovery of rare earth elements was proposed. The process was tested and simulated by commercial software for the chemical processes. The mass balance of the process was calculated: from 1 ton of initial powder it was possible to obtain around 160 kg of a concentrate of rare earths having a purity of 99%. The main rare earths elements in the final product was yttrium oxide (86.43%) following by cerium oxide (4.11%), lanthanum oxide (3.18%), europium oxide (3.08%) and terbium oxide (2.20%). The estimated total recovery of the rare earths elements was around 70% for yttrium and europium and 80% for the other rare earths.

  1. In vitro thermal profile suitability assessment of acids and bases for thermochemical ablation: underlying principles.

    Science.gov (United States)

    Freeman, Laura A; Anwer, Bilal; Brady, Ryan P; Smith, Benjamin C; Edelman, Theresa L; Misselt, Andrew J; Cressman, Erik N K

    2010-03-01

    To measure and compare temperature changes in a recently developed gel phantom for thermochemical ablation as a function of reagent strength and concentration with several acids and bases. Aliquots (0.5-1 mL) of hydrochloric acid or acetic acid and sodium hydroxide or aqueous ammonia were injected for 5 seconds into a hydrophobic gel phantom. Stepwise increments in concentration were used to survey the temperature changes caused by these reactions. Injections were performed in triplicate, measured with a thermocouple probe, and plotted as functions of concentration and time. Maximum temperatures were reached almost immediately in all cases, reaching 75 degrees C-110 degrees C at the higher concentrations. The highest temperatures were seen with hydrochloric acid and either base. More concentrated solutions of sodium hydroxide tended to mix incompletely, such that experiments at 9 M and higher were difficult to perform consistently. Higher concentrations for any reagent resulted in higher temperatures. Stronger acid and base combinations resulted in higher temperatures versus weak acid and base combinations at the same concentration. Maximum temperatures obtained are in a range known to cause tissue coagulation, and all combinations tested therefore appeared suitable for further investigation in thermochemical ablation. Because of the loss of the reaction chamber shape at higher concentrations of stronger agents, the phantom does not allow complete characterization under these circumstances. Adequate mixing of reagents to maximize heating potential and avoid systemic exposure to unreacted acid and base must be addressed if the method is to be safely employed in tissues. In addition, understanding factors that control lesion shape in a more realistic tissue model will be critical. Copyright 2010 SIR. Published by Elsevier Inc. All rights reserved.

  2. Acidic deposition ("acid rain")

    Science.gov (United States)

    Schreiber, R. Kent; LaRoe, Edward T.; Farris, Gaye S.; Puckett, Catherine E.; Doran, Peter D.; Mac, Michael J.

    1995-01-01

    Acidic deposition, or "acid rain," describes any form of precipitation, including rain, snow, and fog, with a pH of 5.5 or below (Note: pH values below 7 are acidic; vinegar has a pH of 3). It often results when the acidity of normal precipitation is increased by sulfates and nitrates that are emitted into the atmosphere from burning fossil fuels. This form of airborne contamination is considered harmful, both directly and indirectly, to a host of plant and animal species.Although acid rain can fall virtually anywhere, ecological damages in environmentally sensitive areas downwind of industrial and urban emissions are a major concern. This includes areas that have a reduced capacity to neutralize acid inputs because of low alkalinity soils and areas that contain species with a low tolerance to acid conditions. To determine the distribution of acidic deposition and evaluate its biological effects, research and monitoring are being conducted by the federal government with support from states, universities, and private industry.            The national extent of the acid rain problem has been estimated by sampling water from 3,000 lakes and 500 streams (Irving 1991), representing more than 28,000 lakes and 56,000 stream reaches with a total of 200,000 km (125,000 mi). Some particularly sensitive areas, such as the Adirondack Mountain region, have been more intensively sampled and the biota examined in detail for effects from acidity.         To identify trends in aquatic ecosystems, present and historical survey data on water chemistry and associated biota are compared. In lakes, the chemical and biological history and pH trends may be inferred or reconstructed in some cases by examining assemblages of fossil diatoms and aquatic invertebrates in the sediment layers. In terrestrial ecosystems, vegetation damage is surveyed and effects of acidic deposition to plants and animals are determined from laboratory and field exposure experiments. Natural

  3. Oral hygiene products and acidic medicines.

    Science.gov (United States)

    Hellwig, E; Lussi, A

    2006-01-01

    Acidic or EDTA-containing oral hygiene products and acidic medicines have the potential to soften dental hard tissues. The low pH of oral care products increases the chemical stability of some fluoride compounds, favors the incorporation of fluoride ions in the lattice of hydroxyapatite and the precipitation of calcium fluoride on the tooth surface. This layer has some protective effect against an erosive attack. However, when the pH is too low or when no fluoride is present these protecting effects are replaced by direct softening of the tooth surface. Xerostomia or oral dryness can occur as a consequence of medication such as tranquilizers, anti-histamines, anti-emetics and anti-parkinsonian medicaments or of salivary gland dysfunction e.g. due to radiotherapy of the oral cavity and the head and neck region. Above all, these patients should be aware of the potential demineralization effects of oral hygiene products with low pH and high titratable acids. Acetyl salicylic acid taken regularly in the form of multiple chewable tablets or in the form of headache powder as well chewing hydrochloric acids tablets for treatment of stomach disorders can cause erosion. There is most probably no direct association between asthmatic drugs and erosion on the population level. Consumers, patients and health professionals should be aware of the potential of tooth damage not only by oral hygiene products and salivary substitutes but also by chewable and effervescent tablets. Additionally, it can be assumed that patients suffering from xerostomia should be aware of the potential effects of oral hygiene products with low pH and high titratable acids.

  4. 供水井酸处理井壁管防腐效果实验及分析%Experiment and Analysis on Preservative Treatment of Casing Pipes in Water-Supply Well Acidizing

    Institute of Scientific and Technical Information of China (English)

    韩超亚

    2011-01-01

    供水井酸处理井壁管防腐处理好坏,直接影响供水井寿命及实际效益.然而,该问题一直没有得到很好的解决.通过进行大量实验,肯定了过去供水井酸处理中井壁管防腐方法,并得到一些新的实验结论.分析认为,在盐酸中加入甲醛是目前供水井酸处理最经济有效的防腐方法,且尽可能使用稀盐酸进行供水井酸处理,浓度32%和10%盐酸在原酸中分别加入原酸重量的2%和1%甲醛溶液,能发挥最佳防腐效果.%Water-supply benefit and effect are directly affected by preservative treatment effect of casing pipes in water-supply well acidizing. However,this issue has not been well solved Through many experiments, the previous preservative treatment method was verified and some new experimental conclusions were proposed: for casing pipes in water-supply well acidizing,adding formaldehyde in hydrochloric acid is the most economical and effective preservative treatment method. In order to achieve the greatest anticorro-sion effect, well acid treatment should use dilute hydrochloric acid. Moreover, the optimum amount of formaldehyde added to hydrochloric acid with concentration of 32% and 10%,are 2% and 1% of the original acid weight,respectively.

  5. Low positive end-expiratory pressure does not exacerbate nebulized-acid lung injury in dogs.

    Science.gov (United States)

    Pellett, Andrew A; Welsh, David A; deBoisblanc, Bennett P; Lipscomb, Gary; Johnson, Royce W; Lord, Kevin C; Levitzky, Michael G

    2005-03-01

    It is not clear if low end-expiratory pressures contribute to ventilator-induced lung injury in large animals. We sought to determine whether ventilation with a low level of positive end-expiratory pressure (PEEP) worsens preexisting permeability lung injury in dogs. Lung injury was initiated in 20 mongrel dogs by ventilating with nebulized 3N hydrochloric acid until a lower inflection point (LIP) appeared on the respiratory system pressure-volume loop. One group of 10 dogs was then ventilated for 4 hours with PEEP set below the LIP (low PEEP), whereas the remaining group of dogs was ventilated for the same time period with similar tidal volumes but with PEEP set above the LIP (high PEEP). We found histologic evidence of reduced alveolar volumes in the low-PEEP animals. However, there were no differences in neutrophil infiltration, lung lobe weights, pulmonary capillary hemorrhage or congestion, or arterial endothelin-1 concentration between the 2 protocol groups. In conclusion, we were unable to demonstrate that ventilation with PEEP set below the LIP exacerbates hydrochloric acid-induced lung injury in dogs.

  6. Electrochemical Corrosion Behavior of Nd-Fe-B Sintered Magnets in Different Acid Solutions

    Institute of Scientific and Technical Information of China (English)

    Zheng Jingwu; Jiang Liqiang; Chen Qiaoling

    2006-01-01

    Electrochemical corrosion behavior of Nd-Fe-B sintered magnets in nitric acid, hydrochloric acid, sulfuric acid, phosphate acid and in oxalic acid was studied.Potentiodynamic polarization curves and immersion time dependence of corrosion rates of Nd-Fe-B sintered magnets in different acid solutions were tested.Microstructures of corroded Nd-Fe-B sintered magnets were investigated by means of SEM and AFM.The results indicate that in strong acid solutions of similar hydrogen ion concentration, the corrosion current increases in the order of HCl>H2SO4>HNO3 solution and Nd-Fe-B sintered magnets are passivated in phosphate acid and oxalic acid.Within 25 min, the corrosion rates of Nd-Fe-B sintered magnets in H2SO4 and H3PO4 solutions show a declining trend with immersion time, while in HNO3 and HCl solutions the corrosion rates are rising.And in H2C2O4 solution, weight of the magnets increases.The brim of Nd-Fe-B sintered magnets is corroded rather seriously and the size of the magnets changed greatly in nitric acid.The surfaces of the corroded magnets in the above mentioned acid solutions are all coarse.

  7. Theoretical stusy of the reaction between 2,2',4' - trihydroxyazobenzene-5-sulfonic acid and zirconium

    Science.gov (United States)

    Fletcher, Mary H.

    1960-01-01

    Zirconium reacts with 2,2',4'-trihydroxyazobenzene-5-sulfonic acid in acid solutions to Form two complexes in which the ratios of dye to zirconium are 1 to 1 and 2 to 1. Both complexes are true chelates, with zirconium acting as a bridge between the two orthohydroxy dye groups. Apparent equilibrium constants for the reactions to form each of the complexes are determined. The reactions are used as a basis for the determination of the active component in the dye and a graphical method for the determination of reagent purity is described. Four absorption spectra covering the wave length region from 350 to 750 mu are given, which completely define the color system associated with the reactions in solutions where the hydrochloric acid concentration ranges from 0.0064N to about 7N.

  8. Synergistic extraction of praseodymium with 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinoline

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qian; WU Dong-bei; BAO Bo-rong

    2009-01-01

    The synergistic extraction of Pr3+ from hydrochloric medium using mixture of 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (P507, HL) and 8-Hydroxyquinoline (HQ) in heptane was investigated. The effect of equilibrium of aqueous acidity on extraction of Pr3+ was discussed. The effect of extractant concentraction, different diluents, equilibrium time and acetate ion concentration on extraction reaction were also studied. With a method of double-logarithmic slope, composition of the extracted species on 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinolinc was derived. The result shows that the synergistic extraction system not only overcomes emulsification of 8-Hydroxyquinoline, but also shows perfect capacity of synergistic extraction. The largest synergistic enhancement factor can be calculated to be 5.49 at pH 3.6 for Pr3+.

  9. Tetranitroacetimidic acid: a high oxygen oxidizer and potential replacement for ammonium perchlorate.

    Science.gov (United States)

    Vo, Thao T; Parrish, Damon A; Shreeve, Jean'ne M

    2014-08-27

    Considerable work has been focused on developing replacements for ammonium perchlorate (AP), a primary choice for solid rocket and missile propellants, due to environmental concerns resulting from the release of perchlorate into groundwater systems [corrected]. Additionally, the generation of hydrochloric acid contributes to high concentrations of acid rain and to ozone layer depletion. En route to synthesizing salts that contain cationic FOX-7, a novel, high oxygen-containing oxidizer, tetranitroacetimidic acid (TNAA), has been synthesized and fully characterized. The properties of TNAA were found to be exceptional, with a calculated specific impulse exceeding that of AP, leading to its high potential as a replacement for AP. TNAA can be synthesized easily in a one-step process by the nitration of FOX-7 in high yield (>93%). The synthesis, properties, and chemical reactivity of TNAA have been examined.

  10. A New Green Ionic Liquid-Based Corrosion Inhibitor for Steel in Acidic Environments

    Directory of Open Access Journals (Sweden)

    Ayman M. Atta

    2015-06-01

    Full Text Available This work examines the use of new hydrophobic ionic liquid derivatives, namely octadecylammonium tosylate (ODA-TS and oleylammonium tosylate (OA-TS for corrosion protection of steel in 1 M hydrochloric acid solution. Their chemical structures were determined from NMR analyses. The surface activity characteristics of the prepared ODA-TS and OA-TS were evaluated from conductance, surface tension and contact angle measurements. The data indicate the presence of a double bond in the chemical structure of OA-TS modified its surface activity parameters. Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS measurements, scanning electron microscope (SEM, Energy dispersive X-rays (EDX analysis and contact angle measurements were utilized to investigate the corrosion protection performance of ODA-TS and OA-TS on steel in acidic solution. The OA-TS and ODA-TS compounds showed good protection performance in acidic chloride solution due to formation of an inhibitive film on the steel surface.

  11. Characterization of the products formed by the reaction of trichlorocyanuric acid with 2-propanol.

    Science.gov (United States)

    Sandercock, P Mark L; Barnett, Julie S

    2009-11-01

    We report a recent investigation into the death of a cat that was initially thought to involve intentionally burning the animal via the use of an ignitable liquid. The exposure of the animal to flame was ruled out. Instead, forensic investigation revealed the intentional mixing together of a common outdoor swimming pool chlorinator, trichlorocyanuric acid (TCCA), and 2-propanol (aka, isopropyl alcohol or rubbing alcohol). The reaction of these two chemicals resulted in the formation of cyanuric acid residue, hydrochloric acid, and the evolution of a significant volume of chlorine gas. Further alpha-chlorination side reactions also occurred between 2-propanol and TCCA to produce a variety of chlorinated 2-propanone species that were detected on the submitted evidence. The identification of the products of both the main reaction and the side reactions allowed the authors to determine what chemicals were originally mixed together by the culprit.

  12. Removal of fluoride ion from aqueous solution by a cerium-poly(hydroxamic acid) resin complex.

    Science.gov (United States)

    Haron, M J; Yunus, W M

    2001-05-01

    A cerium-loaded poly(hydroxamic acid) chelating ion exchanger was used for fluoride ion removal from aqueous solution. The resin was effective in decreasing the fluoride concentration from 5 mM down to 0.001 mM in acidic pH between 3 and 6. The sorption followed a Langmuir model with a maximum capacity of 0.5 mmol/g. The removal is accomplished by an anion exchange mechanism. The rate constant for the sorption was found to be 9.6 x 10(-2) min-1. A column test shows that the fluoride ion was retained on the column until breakthrough point and the fluoride sorbed in the column can be eluted with 0.1 M NaOH. The column can be reused after being condition with hydrochloric acid at pH 4. The resin was tested and found to be effective for removal of fluoride from actual industrial wastewater.

  13. Soil washing of chromium- and cadmium-contaminated sludge using acids and ethylenediaminetetra acetic acid chelating agent.

    Science.gov (United States)

    Gitipour, Saeid; Ahmadi, Soheil; Madadian, Edris; Ardestani, Mojtaba

    2016-01-01

    In this research, the effect of soil washing in the removal of chromium- and cadmium-contaminated sludge samples collected from Pond 2 of the Tehran Oil Refinery was investigated. These metals are considered as hazardous substances for human health and the environment. The carcinogenicity of chromate dust has been established for a long time. Cadmium is also a potential environmental toxicant. This study was carried out by collecting sludge samples from different locations in Pond 2. Soil washing was conducted to treat the samples. Chemical agents, such as acetic acid, ethylenediaminetetra acetic acid (EDTA) and hydrochloric acid, were used as washing solutions to remove chromium and cadmium from sludge samples. The results of this study indicated that the highest removal efficiencies from the sludge samples were achieved using a 0.3 M HCl solution with 82.69% and 74.47% for chromium and cadmium, respectively. EDTA (0.1 M) in the best condition extracted 66.81% of cadmium and 72.52% of chromium from the sludges. The lowest efficiency values for the samples, however, were achieved using 3 M acetic acid with 41.7% and 46.96% removals for cadmium and chromium, respectively. The analysis of washed sludge indicated that the heavy metals removal decreased in the order of 3 M acetic acid acid appears to offer a greater potential as a washing agent in remediating the sludge samples.

  14. Inhibition of acidic corrosion of aluminum by triazoline derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Khamis, E. (Alexandria Univ., Ibrahimia (Egypt). Dept. of Chemistry); Atea, M. (Alexandria Univ., Ibrahimia (Egypt). Dept. of Materials Science)

    1994-02-01

    Inhibition of the corrosion of aluminum (Al) in hydrochloric acid (HCl) by some triazoline derivatives was studied in relation to the concentration of the inhibitors using gasometry, the weight-loss method, and the potentiodynamic technique. All compounds investigated were found to be inhibitors of the mixed type. The inhibitory character of the additives depended upon the +R (resonance) and +I (inductive) powers of alkyl or aryl groups of the triazoline derivatives. Inhibition was ascribed to the adsorption of the inhibitor onto the metal oxide surface following the Flory-Huggins isotherm. The compounds were adsorbed on the metal surface. Each molecule of the inhibitors occupied an average of 3.8 active sites on the metal surface. The values of activation free energies varied between [minus]30 kJ/mol and [minus]45 kJ/mol.

  15. Iron extraction from pyrite cinder by mixed acid%双酸法提取硫铁矿烧渣中铁

    Institute of Scientific and Technical Information of China (English)

    刘培; 江健; 刘宗宽; 张磊; 贺延龄

    2013-01-01

    Extraction of iron from pyrite cinder by mixed acid of sulfuric acid and hydrochloric acid,and main factors influencing iron leaching rate were investigated.In order to analyze feasibility of extraction of iron from pyrite cinder,the main elements were determined by using X-ray fluorescence spectrum analyzer (XRF).The crystal type of iron oxide in the pyrite cinder was also analyzed by X-ray diffraction (XRD) to understand the presence forms of iron in pyrite cinder.First,10 g dried pyrite cinder were added to a 250 ml three-necked flask.Then,sulfuric acid and hydrochloric acid of specified concentration and quantity were gradually added into the flask under proper stirring,and were kept at a specific temperature for several hours.After filtration,the solution was diluted to 250 ml with distilled water.The diluted solution was used for determination of iron content in leacheate using the stannous chloride-mercury chloridepotassium dichromate method.At last extraction conditions were optimized.The results showed that the significances of each factor on iron extraction were as follows:concentration of sulfuric acid>hydrochloric acid amount>reaction time>sulfuric acid over-dose coefficient.Iron extraction rate increased with higher reaction temperature and increasing amount of hydrochloric acid.However,there existed an optimum combination of sulfuric acid concentration,reaction time and sulfuric acid over-dose coefficient.The optimal conditions were reaction temperature 118-125℃,reaction time 3 h,sulfuric acid concentration 50%-60%,and hydrochloric acid 0.25 ml · (g pyrite cinder)-1,sulfuric acid over-dose coefficient 1.2.Under these conditions,the extraction yield of iron was 93.1%,much higher than that by a single acid.So,the process can improve utilization of iron resource.%应用硫酸-盐酸混酸浸出回收硫铁矿烧渣中的铁,探讨了主要因素对铁浸取率的影响,确定了最佳浸取条件.结果表明,各因素对铁浸取率影

  16. Enhanced conductivity of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) film by acid treatment for indium tin oxide-free organic solar cells

    Science.gov (United States)

    Lin, Chun-Chiao; Huang, Chih-Kuo; Hung, Yu-Chieh; Chang, Mei-Ying

    2016-08-01

    An acid treatment is used in the enhancement of the conductivity of the conducting polymer poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) thin film, which is often used as the anode in organic solar cells. There are three types of acid treatment for PEDOT:PSS thin film: hydrochloric, sulfuric, and phosphoric acid treatments. In this study, we examine and compare these three ways with each other for differences in conductivity. Hydrochloric acid results in the highest conductivity enhancement, from 0.3 to 1109 S/cm. We also discuss the optical transmittance, conductivity, surface roughness, surface morphology, and stability, as well as the factors that can influence device efficiency. The devices are fabricated using an acid-treated PEDOT:PSS thin film as the anode. The highest power conversion efficiency was 1.32%, which is a large improvement over that of the unmodified organic solar cell (0.21%). It is comparable to that obtained when using indium tin oxide (ITO) as an electrode, ca. 1.46%.

  17. Selection of suitable mineral acid and its concentration for biphasic dilute acid hydrolysis of the sodium dithionite delignified Prosopis juliflora to hydrolyze maximum holocellulose.

    Science.gov (United States)

    Naseeruddin, Shaik; Desai, Suseelendra; Venkateswar Rao, L

    2016-02-01

    Two grams of delignified substrate at 10% (w/v) level was subjected to biphasic dilute acid hydrolysis using phosphoric acid, hydrochloric acid and sulfuric acid separately at 110 °C for 10 min in phase-I and 121 °C for 15 min in phase-II. Combinations of acid concentrations in two phases were varied for maximum holocellulose hydrolysis with release of fewer inhibitors, to select the suitable acid and its concentration. Among three acids, sulfuric acid in combination of 1 & 2% (v/v) hydrolyzed maximum holocellulose of 25.44±0.44% releasing 0.51±0.02 g/L of phenolics and 0.12±0.002 g/L of furans, respectively. Further, hydrolysis of delignified substrate using selected acid by varying reaction time and temperature hydrolyzed 55.58±1.78% of holocellulose releasing 2.11±0.07 g/L and 1.37±0.03 g/L of phenolics and furans, respectively at conditions of 110 °C for 45 min in phase-I & 121 °C for 60 min in phase-II.

  18. Synthesis and antiulcer activity evaluation of conjugates of amino acids with N-aroyl- N, N'-dicyclohexyl urea

    Directory of Open Access Journals (Sweden)

    Subudhi Bharat

    2011-12-01

    Full Text Available Abstract Amino acids are safe molecules with variable efficacy against ulceration. Considering the good antioxidant potential of N-aroyl- N, N'-dicyclohexyl urea and antiulcer activities of amino acids, a series of amino acid conjugates of N-aroyl- N, N'-dicyclohexyl urea was synthesized and the effect against ulceration in albino rats induced by pyloric ligation was screened. All these compounds were found to be safe and active. Reduction of ulcer index was significant for all compounds. Conjugates of methionine and histidine exhibited enhanced antiulcer activity comparable to omeprazole in terms of inhibition of release of gastric juice, hydrochloric acid and neutralization activity. The promising efficacy and safety of these compounds is interesting for further investigation.

  19. Novel technology for sewage sludge utilization: preparation of amino acids chelated trace elements (AACTE) fertilizer.

    Science.gov (United States)

    Liu, Yangsheng; Kong, Sifang; Li, Yaqiong; Zeng, Hui

    2009-11-15

    This study developed a novel technology for sewage sludge utilization. The bacteria proteins in the sewage sludge were extracted to produce the amino acid chelated trace elements (AACTE) fertilizer by virtue of several chemical processes. Firstly, the sewage sludge was hydrolyzed under hot hydrochloric acid solution to obtain protein solution. The effects of hydrolysis temperature, reaction time and pH on the extraction ratio of protein from the sewage sludge were investigated. Secondly, the protein solution was further hydrolyzed into amino acids under hot acid condition. The effects of the HCl dosage, hydrolysis temperature and reaction time on the yields of amino acids were investigated in detail. Thirdly, the raw amino acids solution was purified by activated carbon decolorization and glacial acetic acid dissolution. Finally, the purified amino acids were used to produce the AACTE fertilizer by chelating with trace elements. Results showed that, under optimum hydrolysis conditions, 78.5% of protein was extracted from the sewage sludge and the amino acids yield was 10-13 g per 100g of dry sludge. The AACTE fertilizer produced was in accordance with China Standard for Amino Acids Foliar Fertilizer. This novel technology is more environmentally friendly compared with the conventional sludge treatments.

  20. Lactic acid demineralization of shrimp shell and chitosan synthesis

    Directory of Open Access Journals (Sweden)

    Alewo Opuada AMEH

    2015-05-01

    Full Text Available The use of lactic acid was compared to hydrochloric acid for shrimp shell demineralization in chitosan synthesis. Five different acid concentrations were considered for the study: 1.5M, 3.0M, 4.5M, 6.0M and 7.5M. After demineralization, the shrimp shell were deproteinized and subsequently deacetylated to produce chitosan using sodium hydroxide solution. The synthesized chitosan samples were characterized using solubility, FTIR, SEM, XRD and viscosity. The SEM, FTIR and XRD analysis indicated that chitosan was synthesized with a high degree of deacetylation (83.18±2.11 when lactic acid was used and 84.2±5.00 when HCl was used. The degree of deacetylation and the molecular weight of the chitosan samples were also estimated. ANOVA analysis (at 95% confidence interval indicated that acid type and concentration did not significantly affect the solubility, degree of deacetylation, viscosity and molecular weight of the chitosan within the range considered.

  1. 饲用酸化剂中甲酸、乙酸、丙酸、乳酸、柠檬酸的同步测定%Determination of formic acid, acetic acid, propionic acid, lactic acid, citric acid in feed acidifier

    Institute of Scientific and Technical Information of China (English)

    索德成; 李兰; 樊霞

    2012-01-01

    A method of the simultaneous determination of the contents of formic acid, acetic acid, propionic acid, lactic acid, citric acid in feed acidifier by HPLC was established. The separation was performed on Grom-Silorg acid(250 mm×4.6 mm, 5 μm) with the mobile phase of hydrochloric acid solution (pH 2.5)/The detection wave length was 210 nm.The flow rate was 1,0 ml/min and the column temperature was 30 ℃.Good linearities of five acid were showed. The average recoveries were greater than 85% respectively, RSD was less than 10.0%.The result of real sample have been shown: the method was simple, rapid and reliable for the simultaneous determination of formic acid, acetic acid, propionic acid, lactic acid, citric acid in organic acids.%实验建立利用高效液相色谱同时测定饲用酸化剂中甲酸、乙酸、丙酸、乳酸、柠檬酸含量的方法.采用Grom-Sil org acid柱(250 mm×2.1 mm,5μm)进行分析.流动相为pH值2.5磷酸水溶液;流速为1.0 ml/min;检测波长为210 nm;柱温为30℃.在此色谱条件下,5种有机酸分离良好.平均回收率均大于85%,RSD小于10.0%.对实际样品的检测结果表明:该方法操作简便易行,准确可靠.

  2. Effects of Acidic Compounds on SO2 Absorption and Desorption Property of 1,4-bis(2-hydroxypropyl)piperazine Aqueous Solution%酸性组分对 N,N′-二(2-羟丙基)哌嗪吸收/解吸 SO2性能的影响

    Institute of Scientific and Technical Information of China (English)

    崔鹏; 刘建芳; 王琪; 王婷婷

    2013-01-01

      Effects of SO3, HCl and HF acidic gases on the SO2 absorption and desorption performance of 1,4-bis(2-hydroxypropyl)piperazine (HPP) was investigated respectively by adding sulphuric acid, hydrochloric acid and hydrofluoric acid into the simulated solution. The results indicate that with increasing sulphuric acid, hydrochloric acid or hydrofluoric acid concentration in the absorption solution, the saturated absorption capacity and the absorption efficiency of SO2 decrease gradually, and the desorption ratio of absorption solution increases gradually. The effects of the same concentration of sulphuric acid and hydrochloric on the SO2 absorption performance of HPP solution show similar trends, and more pronounce than that of the same concentration of hydrofluoric acid. Adding 0.5 mol sulphuric acid or 1 mol hydrochloric acid into 1 mol absorption solution, the saturated absorption capacity reduces 0.47 mol⋅mol−1, while adding 1 mol hydrofluoric acid into 1 mol absorption solution, the saturated absorption capacity reduces 0.44 mol⋅mol−1. The errors of saturated absorption capacities between the theoretical calculation and experimental values are less than ±1%.%  通过添加硫酸、盐酸和氢氟酸模拟研究了 SO3、HCl 和 HF 三种酸性气体对 N,N’-二(2-羟丙基)哌嗪(HPP)吸收解吸 SO2性能的影响。研究结果表明,随着吸收液中硫酸、盐酸和氢氟酸的浓度逐渐增大,吸收液的饱和吸收量和脱硫率逐渐降低,解吸率逐渐增大。添加相同浓度 H+的硫酸和盐酸对 HPP 吸收 SO2性能的影响效果基本相当,且大于相同浓度H+的氢氟酸。每摩尔吸收液中添加0.5 mol 硫酸或1 mol 盐酸,吸收液饱和吸收量减少0.47 mol⋅mol−1;每摩尔吸收液中添加1 mol 氢氟酸,饱和吸收量减少0.44 mol⋅mol−1,饱和吸收量的理论计算值与实验值偏差率小于±1%。

  3. Thermal degradation kinetics of polylactic acid/acid fabricated cellulose nanocrystal based bionanocomposites.

    Science.gov (United States)

    Monika; Dhar, Prodyut; Katiyar, Vimal

    2017-11-01

    Cellulose nanocrystals (CNC) are fabricated from filter paper (as cellulosic source) by acid hydrolysis using different acids such as sulphuric (H2SO4), phosphoric (H3PO4), hydrochloric (HCl) and nitric (HNO3) acid. The resulting acid derived CNC are melt mixed with Polylactic acid (PLA) using extruder at 180°C. Thermogravimetric (TGA) result shows that increase in 10% and 50% weight loss (T10, T50) temperature for PLA-CNC film fabricated with HNO3, H3PO4 and HCl derived CNC have improved thermal stability in comparison to H2SO4-CNC. Nonisothermal kinetic studies are carried out with modified-Coats-Redfern (C-R), Ozawa-Flynn-Wall (OFW) and Kissinger method to predict the kinetic and thermodynamic parameters. Subsequently prediction of these parameter leads to the proposal of thermal induced degradation mechanism of nanocomposites using Criado method. The distribution of Ea calculated from OFW model are (PLA-H3PO4-CNC: 125-139 kJmol(-1)), (PLA-HNO3-CNC: 126-145 kJmol(-1)), (PLA-H2SO4-CNC: 102-123 kJmol(-1)) and (PLA-HCl-CNC: 140-182 kJmol(-1)). This difference among Ea for the decomposition of PLA-CNC bionanocomposite is probably due to various acids used in this study. The Ea calculated by these two methods are found in consonance with that observed from Kissinger method. Further, hyphenated TG-Fourier transform infrared spectroscopy (FTIR) result shows that gaseous products such as CO2, CO, lactide, aldehydes and other compounds are given off during the thermal degradation of PLA-CNC nanocomposite. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Characteristic of synergistic extraction of oxalic acid with system from rare earth metallurgical wastewater

    Institute of Scientific and Technical Information of China (English)

    QIU

    2010-01-01

    Large amount of high concentration acidic wastewater would be produced in the conversion process of chloride rare earth into oxide rare earth.It was a mixed solution of oxalic acid and hydrochloric acid,so the recycling use was very difficult.The method of liquid-liquid extraction was proposed in this paper to achieve wastewater treatment and reclamation.The mechanism of extraction of oxalic acid from the wastewater with the systems of 50% TOB+45% kerosene and 5% 2-ethyl hexanol was investigated.The composition and structure of the extracted species and the establishment of the mathematical model of the oxalic acid extraction were determined by the use of saturation method,equimolar series method.The results showed that extraction of oxalic acid by TOB was a neutral association extraction,oxalic acid existed mainly in a molecular form in the organic phase,and the extraction combination ratio was 2:1.The duality extraction system composed of extractant TOB and TOC had synergistic extraction effect on oxalic acid and chlorhydric acid,and the extraction dislribution ratio was improved greatly.The optimum volume fiaction of TOB was 0.6-0.8.

  5. Catalytic Conversion of Glucose into 5-Hydroxymethylfurfural by Hf(OTf4 Lewis Acid in Water

    Directory of Open Access Journals (Sweden)

    Junjie Li

    2015-12-01

    Full Text Available A series of Lewis acidic metal salts were used for glucose dehydration to 5-hydroymethylfurfural (HMF in water. Effect of valence state, ionic radii of Lewis acidic cation, and the type of anions on the catalytic performance have been studied systematically. The experimental results showed that the valence state played an important role in determining catalytic activity and selectivity. It was found that a higher glucose conversion rate and HMF selectivity could be obtained over high valent Lewis acid salts, where the ionic radii of these Lewis acidic metal salts are usually relatively small. Analysis on the effect of the anions of Lewis acid salts on the catalytic activity and the selectivity suggested that a higher glucose conversion and HMF selectivity could be readily obtained with Cl−. Furthermore, the recyclability of high valence state Lewis acid salt was also studied, however, inferior catalytic performance was observed. The deactivation mechanism was speculated to be the fact that high valence state Lewis acid salt was comparatively easier to undergo hydrolysis to yield complicated metal aqua ions with less catalytic activity. The Lewis acidic activity could be recovered by introducing a stoichiometric amount of hydrochloric acid (HCl to the catalytic before the reaction.

  6. Effect of different carbon fillers and dopant acids on electrical properties of polyaniline nanocomposites

    Indian Academy of Sciences (India)

    E Johny Jelmy; S Ramakrishnan; Murali Rangarajan; Nikhil K Kothurkar

    2013-02-01

    Electrically conducting nanocomposites of polyaniline (PANI) with carbon-based fillers have evinced considerable interest for various applications such as rechargeable batteries, microelectronics, sensors, electrochromic displays and light-emitting and photovoltaic devices. The nature of both the carbon filler and the dopant acid can significantly influence the conductivity of these nanocomposites. This paper describes the effects of carbon fillers like carbon black (CB), graphite (GR) and muti-walled carbon nanotubes (MWCNT) and of dopant acids like methane sulfonic acid (MSA), camphor sulfonic acid (CSA), hydrochloric acid (HCl) and sulfuric acid (H2SO4) on the electrical conductivity of PANI. The morphological, structural and electrical properties of neat PANI and carbon–PANI nanocomposites were studied using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT–IR), UV–Vis spectroscopy and the four-point probe technique, respectively. Thermogravimetric analysis (TGA) and X-ray diffraction (XRD) studies were also conducted for different PANI composites. The results show that PANI and carbon–PANI composites with organic acid dopants show good thermal stability and higher electrical conductivity than those with inorganic acid dopants. Also, carbon–PANI composites generally show higher electrical conductivity than neat PANI, with highest conductivities for PANI–CNT composites. Thus, in essence, PANI–CNT composites prepared using organic acid dopants are most suitable for conducting applications.

  7. 双室浮动床酸碱耗高的原因分析及对策%Reason Analysis and Countermeasure of to Consume High of Hydrochloric Acid and Sodium Hydroxide in the Two Room Floats Bed

    Institute of Scientific and Technical Information of China (English)

    李苏

    2012-01-01

    The arrice introduced Chuang in the stone house east hot electicity.incorporated company hot give or get an electric shock four factories three expect an engineering double double room to float system general situation of seethe the bed and work priniple , craft characteristics and try a luck circumstance, and to a pair of problem that the layer floats a bed to try emergence in luck take into analytical resolve, float design manufacturing and movement of bed to put forward a beneficial suggestion to the double room.%文章介绍了石家庄东方热电股份有限公司热电四厂三期工程双室浮动床的系统概况、工作原理、工艺特点及试运情况,并针对双室双层浮动床出现的问题加以分析解决,对双室浮动床的设计制造及运行提出有益建议。

  8. 采用盐酸溶液从废旧锂离子电池正极还原浸取钴%Reductive leaching of cobalt using hydrochloric acid from cathodes of spent lithium-ion batteries

    Institute of Scientific and Technical Information of China (English)

    乔秀丽; 田军; 马松艳; 赵东江

    2009-01-01

    采用盐酸和双氧水体系为浸取液对废旧锂离子电池正极进行还原处理.正交实验表明,影响Co2+浸出率几种因素强度顺序为:HCl浓度>固液比>H2O2-HCl体积比>反应温度>反应时间.最佳浸取条件为:HCl浓度为3 mol/L,H2O2-HCl体积比为1 ∶ 15,反应时间90 min,反应温度80 ℃,固-液比(g/mL)为1 ∶ 50.此时,Co2+浸出率达到99.6%.

  9. Enhanced corrosion resistance of mild steel in molar hydrochloric acid solution by 1,4-bis(2-pyridyl)-5H-pyridazino[4,5-b]indole: Electrochemical, theoretical and XPS studies

    Energy Technology Data Exchange (ETDEWEB)

    Bentiss, F. [Laboratoire de Cristallochimie et Physicochimie du Solide, CNRS UMR 8012 ENSCL, BP 90108, F-59652 Villeneuve d' Ascq Cedex (France); Laboratoire de Chimie de Coordination et d' Analytique, Universite Chouaib Doukkali, Faculte des Sciences, B.P. 20, El Jadida (Morocco); Gassama, F. [Laboratoire de Chimie Organique EA 2692, Bat. C4, USTL, F-59652 Villeneuve d' Ascq Cedex (France); Barbry, D. [Laboratoire de Chimie Organique EA 2692, Bat. C4, USTL, F-59652 Villeneuve d' Ascq Cedex (France); Gengembre, L. [Laboratoire de Catalyse, CNRS UMR 80100, Bat. C3, USTL, F-59652 Villeneuve dAscq Cedex (France); Vezin, H. [Laboratoire de Chimie Organique et Macromoleculaire, CNRS UMR 8009, USTL Bat C3, F-59655 Villeneuve d' Ascq Cedex (France); Lagrenee, M. [Laboratoire de Cristallochimie et Physicochimie du Solide, CNRS UMR 8012 ENSCL, BP 90108, F-59652 Villeneuve d' Ascq Cedex (France); Traisnel, M. [Laboratoire des Procedes d' Elaboration des Revetements Fonctionnels, UPRES EA 1040 ENSCL, BP 90108, F-59652 Villeneuve d' Ascq Cedex (France)]. E-mail: Michel.Traisnel@ensc-lille.fr

    2006-02-15

    The inhibition effect of the new pyridazine derivative, namely 1,4-bis(2-pyridyl)-5H-pyridazino[4,5-b]indole (PPI) against mild steel corrosion in 1 M HCl solutions was evaluated using weigh loss and electrochemical techniques (potentiodynamic polarisation curves and impedance spectroscopy). The experimental results suggest that PPI is a good corrosion inhibitor and the inhibition efficiency increased with the increase of PPI concentration, while the adsorption followed the Langmuir isotherm. X-ray photoelectron spectroscopy (XPS) and theoretical calculation of electronic density were carried out to establish the mechanism of corrosion inhibition of mild steel with PPI in 1 M HCl medium. The inhibition action of this compound was, assumed to occur via adsorption on the steel surface through the active centres contained of the molecule. The corrosion inhibition is due to the formation of a chemisorbed film on the steel surface.

  10. Scanning electronic microscope observation of the action of lidocaine hydrochloric acid to human sperm in vitro%盐酸利多卡因体外对精子作用的扫描电镜观察

    Institute of Scientific and Technical Information of China (English)

    丁贤胜; 高晓勤; 倪佳

    2010-01-01

    目的 探讨盐酸利多卡因(LHA)体外对人精子形态结构改变的机制.方法 选择健康生育男性8名,年龄23~32岁,禁欲3~7 d后,手淫取精.分为对照组(A组),实验B组(LHA终浓度为5 mg/mL)、实验C组(LHA终浓度为15 mg/mL).体外孵育1、2 h后,采用S3400N扫描电镜观察各组精子形态的改变.结果 与A组相比,实验B组1 h后精子形态结构改变差异无统计学意义(P>0.05),2 h后差异有统计学意义(P<0.05);实验C组1 h后差异有统计学意义(P<0.05),2 h后差异更为明显(P<0.01).结论 随着LHA终浓度的增加和孵育时间的延长,LHA对精子形态结构改变越来越明显.

  11. 地衣酚——盐酸法测定燕麦β葡聚糖中的戊聚糖含量%Orcinol Hydrochloric Acid Method for Determination of Pentosans in Oat β-glucan

    Institute of Scientific and Technical Information of China (English)

    李昊力; 李家林; 张雪飞

    2014-01-01

    目前国内外对从植物提取葡聚糖和戊聚糖的方法较为相似.文章以地衣酚——盐酸法为基础,根据己糖与戊糖混合体系的反应液在吸收光谱670 nm与580 nm处存在最大差谱,进行燕麦β-葡聚糖中戊聚糖的测定.通过精确度和回收率试验验证了该方法进行可行性.

  12. 地衣酚-盐酸测定小麦中戊聚糖含量的研究%Study on Determining the Content of Pentosan in Wheat with Orcinol-hydrochloric acid Method

    Institute of Scientific and Technical Information of China (English)

    冯焱; 佟建明

    2004-01-01

    对2002-2003年华北地区具有代表性的8个小麦品种的戊聚糖进行了测定.不同品种小麦中戊聚糖的平均含量变化范围为6%~9%.不同生态条件下小麦中戊聚糖含量均有很大差异.采用地衣酚-盐酸法测定小麦中戊聚糖的含量,为小麦更好地用作畜禽饲料提供理论依据.

  13. Determination of the mixture in a reaction of glycerol with hydrochloric acid by gas chromatography%气相色谱法测定甘油与盐酸反应过程的混合物

    Institute of Scientific and Technical Information of China (English)

    尤小姿; 李华荣; 罗正鸿

    2009-01-01

    采用气相色谱方法分析了甘油与盐酸反应过程中的主要物质. 使用KB-WAX毛细管柱及FID检测器, 以乙二醇作内标和甲醇定容, 并用内标法计算. 结果表明, 在程序升温下, 气相色谱内标法能使GLY, DCP, CPD等几种物质达到基线分离, 该方法能满足测试要求.%In this paper, a simple gas chromatographic method for the identification of glycerol (GLY), 1,3-dichloropropanol-2-propanol,(DCP) and 3-chloro-1,2-propandiol (CPD) in GLY chlorination reaction is described. The results are detected by KB-WAX capillary column with a flame ionization detector (FID) and calculated by an internal stand method. Glycol is used as an internal standard, and the samples are diluted with methanol. This method is simple, rapid and the results are reliable.

  14. 盐酸米诺环素治疗慢性牙周炎疗效观察%The hydrochloric acid Minuo link element treatment chronic parodontitis curative effect observation

    Institute of Scientific and Technical Information of China (English)

    刘志成; 伍立志

    2008-01-01

    目的:观察盐酸米诺环素治疗慢性牙周炎的疗效.方法:将65例慢性牙周炎患者随机分为两组.对照组应用常规牙周洁治治疗;治疗组在此基础上加用盐酸米诺环素软膏局部使用.观察并对比两组治疗前后牙龈红肿情况、菌斑指数(PLI)、龈沟出血指数(SBI)、牙周袋深度(PD)、牙周附着水平(AL)和牙齿松动度(MD)等情况.结果:治疗组总有效率为87.9%,对照组为71.9%,治疗组疗效高于对照组(P<0.05).两组治疗后PLI、SBI、PD、AL、MD均较治疗前改善(P<0.05或P<0.01);但治疗组的改善情况明显优于对照组(P<0.05或P<0.01).结论:盐酸米诺环素是治疗慢性牙周炎的安全、有效的方法.

  15. Corrosion Inhibition of Yushania Polytricha Leaves Extract for Aluminum in Hydrochloric Acid Media%滑竹叶提取物在盐酸介质中对铝的缓蚀性能

    Institute of Scientific and Technical Information of China (English)

    李向红; 邓书端; 付惠

    2012-01-01

    The inhibition effect of Yushania polytricha leaves extract (YPLE) on the corrosion of aluminum in 1.0 mol/L HC1 media was studied by mass loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy, Fourier transform infrared spectroscopy, ultraviolet spectrophotometry and scanning electron microscope methods. The results show that YPLE is a good inhibitor, and the inhibition efficiency increases with the inhibitor concentration. The adsorption of YPLE on aluminum surface obeys Langmuir adsorption isotherm. YPLE behaves as a cathodic inhibitor. EIS spectra exhibit one capacitive loop at high frequencies followed by an inductive one at low frequency values, and the impedance value increases with the inhibitor concentration. SEM results confirm the corrosion of aluminum is retarded remarkably by the addition of YPLE.%采用失重法、动电位极化曲线、电化学阻抗谱、红外光谱、紫外光谱和扫描电子显微镜研究了滑竹叶提取物(YPLE)在1.0mol/L HCl介质中对铝的缓蚀作用.结果表明,YPLE对铝具有良好的缓蚀作用,缓蚀率随其浓度的增加而增大,且在铝表面的吸附符合Langmuir吸附等温式.YPLE为阴极抑制型缓蚀剂;电化学阻抗谱在高频区呈容抗弧,在低频区呈感抗弧,添加YPLE后,阻抗值显著增大.SEM表明,添加YPLE对铝的腐蚀产生了明显的抑制作用.

  16. Extraction chromatographic separation of uranium (VI) with amberlite LA-1 from malonic acid

    Energy Technology Data Exchange (ETDEWEB)

    Narayanan, P.; Khopkar, S.M.

    1985-12-01

    Uranium(VI) was extracted between pH 2.5 to 6.0 from 0.01 mol dm/sup -3/ malonic acid on a column of silica gel with Aberlite LA-1 as the extractant. It was stripped from the column with 1-2 mol dm/sup -3/ of hydrochloric, sulfuric, and nitric acids. Uranium(VI) was separated from alkali, alkaline earths, manganese, iron, cobalt, nickel, zinc, yttrium, lanthanum, cerium in binary mixtures by exploiting the difference in the pH of formation of malonato complexes. Uranium was separated from zirconium, hafnium, thorium, scandium, and titanium by taking its advantage of stability of chloro or sulfato complexes. The method was tested for the standard reference rock samples. 15 references, 4 figures, 1 table.

  17. Reduction of Ash Content in Raw Coal Using Acids and Alkali

    Directory of Open Access Journals (Sweden)

    K. H. Shivaprasad

    2010-01-01

    Full Text Available Ash, an inorganic matter present in coal is amenable for dissolution using suitable reagents. Thus the dissolution of ash and its subsequent removal reduces the release of many toxic elements into the environment by coal based industries. Removal of ash also enhances the calorific value. In the present investigation an attempt has been made to reduce the ash content of raw coal obtained from nearest thermal power by using hydrochloric acid, sulfuric acid and sodium hydroxide. A series of leaching experiments were conducted on coal of different size fractions by varying the parameters like concentration, temperature and time of leaching. The results indicate that it is possible to remove nearly 75% of ash from coal sample by leaching.

  18. Dealloying of Cu-Based Metallic Glasses in Acidic Solutions: Products and Energy Storage Applications

    Directory of Open Access Journals (Sweden)

    Zhifeng Wang

    2015-04-01

    Full Text Available Dealloying, a famous ancient etching technique, was used to produce nanoporous metals decades ago. With the development of dealloying techniques and theories, various interesting dealloying products including nanoporous metals/alloys, metal oxides and composites, which exhibit excellent catalytic, optical and sensing performance, have been developed in recent years. As a result, the research on dealloying products is of great importance for developing new materials with superior physical and chemical properties. In this paper, typical dealloying products from Cu-based metallic glasses after dealloying in hydrofluoric acid and hydrochloric acid solutions are summarized. Several potential application fields of these dealloying products are discussed. A promising application of nanoporous Cu (NPC and NPC-contained composites related to the energy storage field is introduced. It is expected that more promising dealloying products could be developed for practical energy storage applications.

  19. THE EFFECT OF THE ACID CATALYST ON THE PREPARATION OF MQ SILICONE RESINS

    Institute of Scientific and Technical Information of China (English)

    Wei Huang; Ying Huang; Yun-zhao Yu

    1999-01-01

    MQ silicone resins were prepared through hydrolytic condensation of ethyl polysilicate or tetraethoxysilane and hexamethyl disiloxane. The unit ratio of the MQ resins was determined by 29Si-NMR.The relationship of the unit ratio of the product resins with that in the feed was studied. When the reaction was catalyzed by aqueous hydrochloric acid, and the unit ratio of M to Q in the feed was more than 1, the unit ratio of the product was usually lower than that of the feed. The MQ silicon with an unit ratio of M/Q>2 could not be obtained. However, if the reaction was catalyzed by concentrated sulfuric acid and the reverse hydrolysis process was employed, MQ silicone resin with very high M/Q ratio was successfully prepared.

  20. Acid stress management by Cronobacter sakazakii.

    Science.gov (United States)

    Alvarez-Ordóñez, Avelino; Cummins, Conor; Deasy, Thérèse; Clifford, Tanya; Begley, Máire; Hill, Colin

    2014-05-16

    Cronobacter sakazakii is a foodborne pathogenic microorganism associated with sporadic cases of neonatal meningitis, necrotising enterocolitis, septicaemia, bloody diarrhoea and brain abscesses acquired through the consumption of contaminated powdered infant formula (PIF). This study aimed to investigate the growth of C. sakazakii DPC6529, a particularly stress tolerant clinical isolate, in acidified laboratory media and PIF. The possibility of a stationary-phase acid tolerance response (ATR) was also investigated. C. sakazakii DPC6529 grew in LB broth acidified to pH4.2 with hydrochloric acid (HCl) and was capable of relatively fast growth in PIF acidified to pH5.0 with HCl, representing the stomach pH reported for newborns and infants. Moreover, bacterial growth in LB broth supplemented with 1% (w/v) glucose gave rise to a stationary-phase ATR which resulted in enhanced survival against a subsequent acid challenge at pH3.0. A transposon mutagenesis approach was used to shed light on some of the molecular mechanisms involved in the response C. sakazakii DPC6529 to normally lethal acid exposures. The data suggests that repairing damage in proteins and nucleic acids, posttranscriptional modification of tRNA molecules and maintenance of the integrity of the cellular envelope are key processes in the defence against acid stress. Clones carrying transposon insertions in genes encoding the envelope stress response regulators CpxR and OmpR were identified as acid-sensitive mutants. Further analyses of the ompR defective mutant and its complemented counterpart evidenced that OmpR is a key player in the response of C. sakazakii to acid stress, although it was not essential to mount an active stationary-phase ATR, at least under the tested conditions. The ability of C. sakazakii DPC6529 to grow in acid environments and to develop an adaptive stationary-phase ATR may allow for its survival or even proliferation within the infant gastrointestinal tract after consumption of

  1. Hexavalent chromium recovery by liquid–liquid extraction with 2-octylaminopyridine from acidic chloride media and its sequential separation from other heavy toxic metal ions

    OpenAIRE

    C.P. Mane; S.V. Mahamuni; S. S. Kolekar; Han, S. H.; M. A. ANUSE

    2016-01-01

    A systematic study of extraction of chromium(VI) with 2-octylaminopyridine (2-OAP) in xylene at room temperature has been conducted. Quantitative extraction of chromium(VI) was observed in the 0.4–0.8 M concentration range of hydrochloric acid. From the extracted complex species in the organic phase, chromium(VI) was back extracted with 7 N ammonia (3 × 10 mL), and was determined by spectrophotometric method. Various parameters such as 2-OAP concentration, equilibrium period, effect of variou...

  2. Experiments on solubility of different acidizing fluids to Syrian limestone%不同酸液条件下叙利亚灰岩溶蚀能力的实验研究

    Institute of Scientific and Technical Information of China (English)

    高翔; 蒋建方; 吴川; 刘光普; 李龙; 蒋睿

    2015-01-01

    文章根据 SY/T 6526-2002《盐酸与碳酸盐岩动态反应速率测定方法》,利用高温高压酸岩反应仪进行了普通盐酸、有机盐酸、胶凝酸、乳化酸和地面交联酸与叙利亚灰岩粉末在两个目的层温度95℃和150℃下2.0 h的溶蚀实验。结果显示,五种酸液2.0 h 的酸溶解率都在90%以上,普通盐酸、有机盐酸的溶蚀能力高于胶凝酸、乳化酸和地面交联酸三种缓速酸;95℃下乳化酸和地面交联酸溶解慢、溶解率低,而150℃下是地面交联酸和胶凝酸;适当条件下,“多相隔离”对 H +抑制作用要比高粘度溶液强,而且随着酸液内部高分子之间链接复杂程度的提高,H +被束缚的程度也增大;温度提高增大了酸溶解率,对乳化酸、地面交联酸和胶凝酸影响比较显著,对普通盐酸和有机盐酸不明显。%Acidizing stimulation treatment always plays a very important role in enhancement of the produc-tion of oil and gas wells.Whether the characteristics of the chosen acid fluids used in the acidizing treatment meet the quality of formation determines success of the treatment.With development for more than half cen-tury,it has already evolved from conventional acids including normal hydrochloric acid and mud acid to re-tarded acids including multicomponent acid fluid,emulsified acid fluid,gelled acid fluid and surface cross-linked acid fluid.However,many of the unconventional oil and gas reservoirs are buried very deep,which leads to the reaction temperature between acid and formation rock becomes higher.This can fasten the reac-tion rate of acid and rock,decrease the effective distance of live acid,and lower the efficient acid fluids.The final result is the stimulation treatment cannot remove the damage of near well-bore,increase the production of oil and gas wells and reach the aim of deep-penetration.To solve the problems above,many researchers made character evaluation of only 1 to 2 acid fluids and the

  3. Quantification of total fatty acids in microalgae: comparison of extraction and transesterification methods.

    Science.gov (United States)

    Cavonius, Lillie R; Carlsson, Nils-Gunnar; Undeland, Ingrid

    2014-11-01

    Determination of microalgaes' fatty acid content is often done with chloroform and methanol according to the Bligh and Dyer extraction, though faster methods exist. A number of comparisons between the Bligh and Dyer and faster methods have resulted in contradicting data, possibly due to differences in algae used and the different versions of the Bligh and Dyer method applied. Here, various forms of direct-transesterification (D-TE) and two-step transesterification (2-TE), including three versions developed in our lab, are compared with the original Bligh and Dyer (Can J Biochem Physiol 37: 911-917, 1959) extraction and two modifications thereof (Lee et al. J AOAC Int 79:487-492, 1996, and our own acidified version) on microalgae with different cell walls: Isochrysis galbana, Nannochloropsis oculata, and Phaeodactylum tricornutum. In total, fatty acid extracts from 11 methods were separated and quantified by gas chromatography with mass spectrometry. Results show that, for N. oculata and P. tricornutum, methods based on chloroform-methanol underestimated the fatty acid content compared with the 2-TE and D-TE methods, which gave similar results. Moreover, D-TE methods are faster than chloroform-methanol methods and use chemicals that are less toxic. Of the D-TE methods, the ones using hydrochloric acid and sulfuric acid recovered the most fatty acids, while boron trifluoride recovered slightly less. The main qualitative difference between the fatty acids recovered was that the chloroform-methanol methods recovered less saturated fatty acids in P. tricornutum.

  4. [Spectrophotometric determination of aromatic amino compounds with J-acid].

    Science.gov (United States)

    Yin, Xiao-hang; Shi, Wen-jian; Shen, Xin; Ma, Jun-tao; Li, Liang

    2015-01-01

    The problems such as chromogenic reaction selectivity, reaction rate, sensitivity and water-solubility of azo compounds were considered. The molecular structures of coupling components were theoretically designed and screened in the present research The reaction conditions and methods of chromogenic reaction were investigated. J-Acid (2-amino-5-naphthol-7-sulfonic acid) as a coupling reagent to determine aromatic amino compounds was established. In the presence of potassium bromide, at room temperature, nitrite reacted with aromatic amino compounds in the medium of thin hydrochloric acid. Then diazonium salt reacted with J-Acid in the aqueous solution of sodium carbonate, forming coloured azo dye, which had a maximum adsorption at 480 nm. The molar adsorption coeffcients of aniline, 4-aminobenzene sulfonic acid and 1-naphthylamine were 3. 95 X 10(4), 3. 24 X 10(4) and 3. 91 X 10(4) L . mol-1 . cm-1 , respectively. Experimental results showed that common coexisting ions on the surface water did not affect the results of determination. J-Acid of spectrophotometry was used to determine the samples of Shanghai Fu Xing Dao canal. Meanwhile, recovery experiments by standard addition method were done. Experiment results showed that the recoveries of aniline were in the range of 98. 5%-102. 1%, and RSD was 2. 08%. J-Acid is a common organic reagent. It is soluble in water and low volatile, and its toxicity is much lower than N-ethylenediamine. spectrophotometric determination of aromatic amino compounds by J-Acid has the advantage of high sensitivity, good selectivity, simple rapid operation and accurate results, and thus it can be used for the determination of trace aromatic amino compounds in the environmental water.

  5. Inorganic acid emission factors of semiconductor manufacturing processes.

    Science.gov (United States)

    Chein, HungMin; Chen, Tzu Ming; Aggarwal, Shankar Gopala; Tsai, Chuen-Jinn; Huang, Chun-Chao

    2004-02-01

    A huge amount of inorganic acids can be produced and emitted with waste gases from integrated circuit manufacturing processes such as cleaning and etching. Emission of inorganic acids from selected semiconductor factories was measured in this study. The sampling of the inorganic acids was based on the porous metal denuders, and samples were then analyzed by ion chromatography. The amount of chemical usage was adopted from the data that were reported to the Environmental Protection Bureau in Hsin-chu County according to the Taiwan Environmental Protection Agency regulation. The emission factor is defined as the emission rate (kg/month) divided by the amount of chemical usage (L/month). Emission factors of three inorganic acids (i.e., hydrofluoric acid [HF], hydrochloric acid [HCl], and sulfuric acid [H2SO4]) were estimated by the same method. The emission factors of HF and HCl were determined to be 0.0075 kg/L (coefficient of variation [CV] = 60.7%, n = 80) and 0.0096 kg/L (CV = 68.2%, n = 91), respectively. Linear regression equations are proposed to fit the data with correlation coefficient square (R2) = 0.82 and 0.9, respectively. The emission factor of H2SO4, which is in the droplet form, was determined to be 0.0016 kg/L (CV = 99.2%, n = 107), and its R2 was 0.84. The emission profiles of gaseous inorganic acids show that HF is the dominant chemical in most of the fabricators.

  6. 采用酸浸法从废旧锂离子电池中回收金属钴%The Recovery of Cobalt from the Spent Lithium-ion Batteries Using Acid Leaching Method

    Institute of Scientific and Technical Information of China (English)

    乔秀丽; 田军; 马松艳; 赵东江

    2011-01-01

    The metal cobalt in lithium-ion battery cathode material is recycled by hydrochloric acid-hydrogen peroxide, sulfuric acid-hydrogen peroxide and nitric acid-hydrogen peroxide as the leaching solution, respectively.The influences of concentration, temperature, amount of hydrogen peroxide, reaction time, solid-liquid ratio on leaching efficiency of cobalt ion are studied. Experimental results have shown that the hydrochloric acid-hydrogen peroxide system is the most appropriate leaching solution. The optimum process conditions are 4.0 mol/L of hydrochloric acid concentration, 5:1 of hydrochloric acid-hydrogen peroxide volume ratio, 61 min of reaction time,73℃of reaction temperature and 1:30.3 of solid-liquid ratio (g/mL). Under these conditions, leaching rate of cobalt ion is 99.8%.%分别采用盐酸-30%过氧化氢、硫酸-30%过氧化氢和硝酸-30%过氧化氢为浸取液,回收锂离子电池正极材料中的金属钴,研究了浓度、温度、30%过氧化氢的量、反应时间、固-液比等对钴浸取率的影响.经响应面分析实验结果表明,盐酸-30%过氧化氢最适宜做浸取液,最佳工艺条件为:盐酸浓度为4.0 mol/L,盐酸-30%过氧化氢体积比为5:1,反应时间61 min,反应温度73℃,固-液比(g/mL)为1:30.3,在此条件下,Co2+浸出率达到99.8%.

  7. Amino Acids Composition and Nutritional Functions Analysis of Royal Jelly%蜂王浆中氨基酸含量的测定

    Institute of Scientific and Technical Information of China (English)

    赵丽

    2014-01-01

    To research the amino acids composition and nutritional functions of market sell royal jelly products , we test the 17 amino acids contents by hydrochloric acid hydrolysis pretreatment method and amino acids analyzer, as well as studied the nutritional and physiological functions.%研究市场上热销的不同蜂王浆产品中氨基酸的含量和组成,将市场购置的6种蜂产品经盐酸水解法处理后,用氨基酸自动分析仪同时测定17种氨基酸的含量,并对其氨基酸的组成和生理功效进行分析。

  8. Determination of trace copper in water samples by flame atomic absorption spectrometry after preconcentration on a phosphoric acid functionalized cotton chelator

    Directory of Open Access Journals (Sweden)

    XINGYAN LIU

    2008-02-01

    Full Text Available This paper reports the preparation of a phosphorylated cotton chelator (PCC by solid phase esterification of phosphoric acid (PA onto defatted cotton fibres using urea as the catalyst. The synthesized PCC was employed for the preconcentration of copper from water samples prior to its determination by flame atomic absorption spectrometry (FAAS. The preconcentration of copper was studied under both batch and column techniques. The pH range for the quantitative preconcentration of copper was 4.0–7.0. The sorption time required for each sample was less than 30 min by the batch method. The copper sorption capacity of the PCC was found to be 15.3 mg/g at the optimum pH value. Elution with 1.0 mol dm-3 hydrochloric acid was found to be quantitative. Feasible flow rates of the copper solution for quantitative sorption onto the column packed with PCC were 0.5–4.0 ml min-1, whereas the optimum flow rate of the hydrochloric acid solution for desorption was less than 1.5 ml min-1. An 80-fold preconcentration factor could be achieved under the optimum column conditions. The tolerance limits for common metal ions on the preconcentration of copper and the number of times of column reuse were investigated. The proposed method was successfully applied for the preconcentration and determination of trace copper in natural and drinking water samples by FAAS.

  9. 盐酸副玫瑰苯胺法测定葡萄酒中二氧化硫的方法探讨%The Method Complementarity of Sulfite in Imported Wines by Hydrochloric Para-Roanilin Method

    Institute of Scientific and Technical Information of China (English)

    李小那

    2012-01-01

    This paper reinforced the GB/T 5009.34-2003〈The Determination of Sulphite in Foods〉,to exploringthe inspection method of sulfite dioxide content in imported wines by hydrochloric para-soanilin colormetrymethod.The different amount activated carbon on the middle speed filter paper was used to eliminating theinterference of the fake positive substance in imported wines.The relia-bility of this method was testified bylabeling the rate of recovery and RSD(%).The method is accurate and sensitive with recovery rate of 90.4%-101.2%,RSD(%)2%.It can be used to the inspection batch-bulk imported wines.%对GB/T 5009.34-2003《食品中亚硫酸盐的测定》中盐酸副玫瑰苯胺比色法检验葡萄酒中二氧化硫含量的方法进行探讨。通过加入不同质量的活性炭于中速滤纸过滤的方法消除葡萄酒中假阳性物质对二氧化硫测定干扰,并测定样品的不同浓度点的加标回收率情况,多次试验结果表明,回收率在90.4%~101.2%,相对偏差均小于2%,可以用此方法于进口葡萄酒的批量检验中。

  10. Antioxidative Peptides Derived from Enzyme Hydrolysis of Bone Collagen after Microwave Assisted Acid Pre-Treatment and Nitrogen Protection

    Directory of Open Access Journals (Sweden)

    Jin Sun

    2010-11-01

    Full Text Available This study focused on the preparation method of antioxidant peptides by enzymatic hydrolysis of bone collagen after microwave assisted acid pre-treatment and nitrogen protection. Phosphoric acid showed the highest ability of hydrolysis among the four other acids tested (hydrochloric acid, sulfuric acid and/or citric acid. The highest degree of hydrolysis (DH was 9.5% using 4 mol/L phosphoric acid with a ratio of 1:6 under a microwave intensity of 510 W for 240 s. Neutral proteinase gave higher DH among the four protease tested (Acid protease, neutral protease, Alcalase and papain, with an optimum condition of: (1 ratio of enzyme and substrate, 4760 U/g; (2 concentration of substrate, 4%; (3 reaction temperature, 55 °C and (4 pH 7.0. At 4 h, DH increased significantly (P < 0.01 under nitrogen protection compared with normal microwave assisted acid pre-treatment hydrolysis conditions. The antioxidant ability of the hydrolysate increased and reached its maximum value at 3 h; however DH decreased dramatically after 3 h. Microwave assisted acid pre-treatment and nitrogen protection could be a quick preparatory method for hydrolyzing bone collagen.

  11. Fundamental study of the mechanism and kinetics of cellulose hydrolysis by acids and enzymes. Progress report, June 1, 1975--December 31, 1975

    Energy Technology Data Exchange (ETDEWEB)

    Tsao, G T

    1976-02-01

    This project deals with acidic and enzymatic hydrolysis of cellulosic materials. Highlights of the first eight months of out project are as follows. (1) Essentially homogeneous C/sub 1/, C/sub x/, and Cellobiase enzyme have been isolated from Cellulase-Onozuka of Trichodeima viride origin. Besides the 3 major components, one protein of a molecular weight of 10,000 was purified, which has strong C/sub x/ activity and also another (M.W. 23,000) with strong C/sub 1/ activity. (2) Kinetics of Cellobiase has been investigated and its kinetics constant accurately determined. Immobilization of this enzyme on porous glass was successful. (3) Absorption of SO/sub 2/ at atmospheric pressure increased digestibility of delignated cellulose but not the natural materials such as corn stalk. A pressurizable absorption unit is being built. (4) Kinetics models for purified C/sub 1/ and C/sub x/ are postulated and equations derived. Experimental tests will be made when sufficient quantities of purified C/sub 1/ and C/sub x/ enzyme are prepared. (5) A lignin digesting, white-rot fungus, Pleurotus ostreatus, has cultivated in our laboratory. It has grown well and heavy. (6) A number of electron micrographs were made with untreated cellulosic materials, which showed that the method of drying the specimens for electromicroscopy is important. Ordinary drying procedures will alter their physical structures. A technique, critical point drying, is being practiced, which will not change the structure. (auth)

  12. Dephosphorization of Steelmaking Slag by Leaching with Acidic Aqueous Solution

    Science.gov (United States)

    Qiao, Yong; Diao, Jiang; Liu, Xuan; Li, Xiaosa; Zhang, Tao; Xie, Bing

    2016-09-01

    In the present paper, dephosphorization of steelmaking slag by leaching with acidic aqueous solution composed of citric acid, sodium hydroxide, hydrochloric acid and ion-exchanged water was investigated. The buffer solution of C6H8O7-NaOH-HCl system prevented changes in the pH values. Kinetic parameters including leaching temperature, slag particle size and pH values of the solution were optimized. The results showed that temperature has no obvious effect on the dissolution ratio of phosphorus. However, it has a significant effect on the dissolution ratio of iron. The dephosphorization rate increases with the decrease of slag particle size and the pH value of the solution. Over 90% of the phosphorus can be dissolved in the solution while the corresponding leaching ratio of iron was only 30% below the optimal condition. Leaching kinetics of dephosphorization follow the unreacted shrinking core model with a rate controlled step by the solid diffusion layer, the corresponding apparent activation energy being 1.233 kJ mol-1. A semiempirical kinetic equation was established. After leaching, most of the nC2S-C3P solid solution in the steelmaking slag was selectively dissolved in the aqueous solution and the iron content in the solid residue was correspondingly enriched.

  13. Dissolution of Metal Supported Spent Auto Catalysts in Acids

    Directory of Open Access Journals (Sweden)

    Fornalczyk A.

    2016-03-01

    Full Text Available Metal supported auto catalysts, have been used in sports and racing cars initially, but nowadays their application systematically increases. In Metal Substrate (supported Converters (MSC, catalytic functions are performed by the Platinum Group Metals (PGM: Pt, Pd, Rh, similarly to the catalysts on ceramic carriers. The contents of these metals make that spent catalytic converters are valuable source of precious metals. All over the world there are many methods for the metals recovery from the ceramic carriers, however, the issue of platinum recovery from metal supported catalysts has not been studied sufficiently yet. The paper presents preliminary results of dissolution of spent automotive catalyst on a metal carrier by means of acids: H2SO4, HCl, HNO3, H3PO4. The main assumption of the research was the dissolution of base metals (Fe, Cr, Al from metallic carrier of catalyst, avoiding dissolution of PGMs. Dissolution was the most effective when concentrated hydrochloric acid, and 2M sulfuric acid (VI was used. It was observed that the dust, remaining after leaching, contained platinum in the level of 0.8% and 0.7%, respectively.

  14. Valproic Acid

    Science.gov (United States)

    ... acid is in a class of medications called anticonvulsants. It works by increasing the amount of a ... older (about 1 in 500 people) who took anticonvulsants such as valproic acid to treat various conditions ...

  15. Amino acids

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002222.htm Amino acids To use the sharing features on this page, please enable JavaScript. Amino acids are organic compounds that combine to form proteins . ...

  16. Obeticholic Acid

    Science.gov (United States)

    Obeticholic acid is used alone or in combination with ursodiol (Actigall, Urso) to treat primary biliary cholangitis (PBC; a ... were not treated successfully with ursodiol alone. Obeticholic acid is in a class of medications called farnesoid ...

  17. Ascorbic Acid

    Science.gov (United States)

    Ascorbic acid is used to prevent and treat scurvy, a disease caused by a lack of vitamin C in ... Ascorbic acid comes in extended-release (long-acting) capsules and tablets, lozenges, syrup, chewable tablets, and liquid drops to ...

  18. Mefenamic Acid

    Science.gov (United States)

    Mefenamic acid is used to relieve mild to moderate pain, including menstrual pain (pain that happens before or during a menstrual period). Mefenamic acid is in a class of medications called NSAIDs. ...

  19. Acid mucopolysaccharides

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003368.htm Acid mucopolysaccharides To use the sharing features on this page, please enable JavaScript. Acid mucopolysaccharides is a test that measures the amount ...

  20. Ethacrynic Acid

    Science.gov (United States)

    Ethacrynic acid, a 'water pill,' is used to treat swelling and fluid retention caused by various medical problems. It ... Ethacrynic acid comes as a tablet to take by mouth. It is usually taken once or twice a day ...

  1. Aminocaproic Acid

    Science.gov (United States)

    Aminocaproic acid is used to control bleeding that occurs when blood clots are broken down too quickly. This type ... the baby is ready to be born). Aminocaproic acid is also used to control bleeding in the ...

  2. Aspartic acid

    Science.gov (United States)

    ... body work. It plays a role in: Hormone production and release Normal nervous system function Plant sources of aspartic acid include: avocado, asparagus, and molasses. Animal sources of aspartic acid include: ...

  3. Study on stabilities and electrochemical behavior of V(V) electrolyte with acid additives for vanadium redox flow battery

    Institute of Scientific and Technical Information of China (English)

    Gang; Wang; Jinwei; Chen; Xueqin; Wang; Jing; Tian; Hong; Kang; Xuejing; Zhu; Yu; Zhang; Xiaojiang; Liu; Ruilin; Wang

    2014-01-01

    Several acid compounds have been employed as additives of the V(V) electrolyte for vanadium redox flow battery(VRB) to improve its stability and electrochemical activity. Stability of the V(V) electrolyte with and without additives was investigated with ex-situ heating/cooling treatment at a wide temperature range of-5 ?C to 60 ?C. It was observed that methanesulfonic acid, boric acid, hydrochloric acid, trifluoroacetic acid,polyacrylic acid, oxalic acid, methacrylic acid and phosphotungstic acid could improve the stability of the V(V) electrolyte at a certain range of temperature. Their electrochemical behaviors in the V(V) electrolyte were further studied by cyclic voltammetry(CV), steady state polarization and electrochemical impedance spectroscopy(EIS). The results showed that the electrochemical activity, including the reversibility of electrode reaction, the diffusivity of V(V) species, the polarization resistance and the flexibility of charge transfer for the V(V) electrolyte with these additives were all improved compared with the pristine solution.

  4. Study on ultrasonically enhanced extraction of phytic acid from rice bran%超声波强化提取米糠中植酸研究

    Institute of Scientific and Technical Information of China (English)

    胡爱军; 田玲玲; 郑捷; 孙连立; 王豪

    2012-01-01

      As a native food additive,phytic acid has strong anti–corrosive and antioxidative properties. With rice bran as raw materials,ultrasound was used to improve the extraction yield of phytic acid. The influence of some factors on the extraction yield of phytic acid were investigated,including ultrasonication time,extraction temperature,the ratio of raw material to solvent and hydrochloric acid concentration. and the orthogonal experiment was conducted to optimize the extraction process using HPLC to analyze phytic acid. The results showed that the optimal extraction conditions were ultrasonication time at 8 min,extraction temperature at 40℃,the ratio of raw material to solven at 1∶8 and concentration hydrochloric acid at 0.10 mol/L,under above conditions,the extraction yield of phytic acid was 87.13%.%  植酸是一种天然食品添加剂,具有强烈防腐、抗氧化能力.该实验以米糠为原料,利用超声波强化提取植酸,研究超声时间、提取温度、料液比及盐酸浓度对植酸提取率影响;通过正交试验对提取工艺进行优化,并采用高效液相色谱法对植酸样品进行分析.结果表明,提取米糠中植酸最优工艺为:盐酸浓度0.10 mol/L、料液比(g/mL)1∶8、提取温40℃、超声时间8 min;在上述条件下,对米糠中植酸提取率为87.13%.

  5. Synthesis and Characterization of Modified Epoxy Resins by Silicic Acid Tetraethyl Ester and Nano-SiO2

    Institute of Scientific and Technical Information of China (English)

    李海燕; 张之圣

    2004-01-01

    A kind of modified epoxy resins was obtained by condensation of epoxy resin with silicic acid tetraethyl ester(TEOS) and nano-SiO2. The reactions were performed with hydrochloric acid as a catalyst at 63 °C.The structure, thermal stability and morphological characteristics of the modified epoxy resins were studied through infrared spectra(FT-IR) analysis, thermogravimetric (TG) analysis and scanning electron microscopy respectively. It has been found from the IR and TG study that modified epoxy resins have greater thermal stability than epoxy resins, and its thermal stability has been improved by the formation of inter-crosslinked network structure. The modified epoxy resins exhibit heterogeneous morphology and heterogeneity increases with more TEOS feeding, which in turn confirms the formation of inter-crosslinked network structure in modified epoxy resins.

  6. Indium recovery from acidic aqueous solutions by solvent extraction with D2EHPA: a statistical approach to the experimental design

    Directory of Open Access Journals (Sweden)

    Fortes M.C.B.

    2003-01-01

    Full Text Available This experimental work presents the optimization results of obtaining a high indium concentration solution and minimum iron poisoning by solvent extraction with D2EHPA solubilized in isoparaffin and exxsol. The variables studied in the extraction step were D2EHPA concentration, acidity of the aqueous phase and time of contact between phases. Different hydrochloric and sulfuric acid concentrations were studied for the stripping step. The optimum experimental conditions resulted in a solution with 99% indium extraction and less than 4% iron. The construction of a McCabe-Thiele diagram indicated two theoretical countercurrent stages for indium extraction and at least six stages for indium stripping. Finally, the influence of associated metals found in typical sulfate leach liquors from zinc plants was studied. Under the experimental conditions for maximum indium extraction, 96% indium extraction was obtained, iron extraction was about 4% and no Ga, Cu and Zn were co-extracted.

  7. Comparative NH 3-sensing characteristic studies of PANI/TiO II nanocomposite thin films doped with different acids

    Science.gov (United States)

    Tai, Huiling; Jiang, Yadong; Xie, Guangzhong; Yu, Junsheng; Ying, Zhihua; Chen, Xuan

    2008-02-01

    Polyaniline/titanium dioxide (PANI/TiO II) nanocomposite thin films were synthesized by in-situ self-assembly method, which were doped with p-toluene sulphonic acid (p-TSA) and hydrochloric acid (HCl), respectively. The thin films were characterized by using UV-Vis absorption spectroscopy and scanning electron microscope (SEM), and the NH 3 gas sensitive properties of the thin films were investigated at room temperature. The results showed that the PANI/TiO II thin film doped with HCl was superior to that doped with p-TSA in terms of response-recovery characteristics. The surface morphology characterization of the thin films were performed to explain the different gas-sensing properties.

  8. [Technological process of cell disruption for extracting astaxanthin from Phaffia rhodozyma by acid method under autoclave conditions].

    Science.gov (United States)

    Lu, Baoju; Xiao, Anfeng; Lil, Lijun; Ni, Hui; Cai, Huinong; Su, Wenjin

    2008-07-01

    Phaffia rhodozyma is one of the organisms for production of astaxanthin, and the key process for extracting intracellular astaxanthin is cell disruption. In this work, cell disruption for extracting astaxanthin from Phaffia rhodozyma was studied with autoclave method at low acid concentration. The optimum disrupting conditions were: autoclave pressure 0.1 MPa, 121 degrees C; hydrochloric acid concentration 0.5 mol/L; liquid to material ratio (V/W) 30 mL/g dry cell weight and disruption time 2 min. Under the optimum conditions, medium scale experiment showed that astaxanthin and total carotenoids recovery from Phaffia rhodozyma were (84.8 +/- 3.2)% and (93.3 +/- 2)%, respectively. This new method can lead to no poisonous residues and get high extraction yield, which have good prospects to be put into industrial production.

  9. The Effect of Various Acids on Properties of Microcrystalline Cellulose (MCC) Extracted from Rice Husk (RH)

    Science.gov (United States)

    Nur Hanani, A. S.; Zuliahani, A.; Nawawi, W. I.; Razif, N.; Rozyanty, A. R.

    2017-05-01

    Microcrystalline cellulose (MCC) was successfully extracted from rice husk (RH) via acid hydrolysis process using nitric acid (HNO3) in comparison with sulphuric acid (H2SO4) and hydrochloric acid (HCl). MCC-RH extracted using HNO3 produced the highest percentage yield at 83.5% as compared to H2SO4 and HCl at 80.6% and 81.8% respectively. Analysis of Fourier Transform Infrared (FTIR) spectroscopy affirmed the successive elimination of non-cellulosic material from RH cellulose resulting highly purified MCC-RH. X-ray Diffraction (XRD) analysis showed MCC-RH treated with HCl gives the highest crystallinity index value of 54.2% while HNO3 and H2SO4 produced comparable results of 52.4% and 49.7% respectively. The results indicate successive extraction of MCC-RH using HNO3 that has great potential to replace strong acid such as H2SO4 and HCl in acid hydrolysis.

  10. A sulfuric-lactic acid process for efficient purification of fungal chitosan with intact molecular weight.

    Science.gov (United States)

    Naghdi, Mitra; Zamani, Akram; Karimi, Keikhosro

    2014-02-01

    The most recent method of fungal chitosan purification, i.e., two steps of dilute sulfuric acid treatment, pretreatment of cell wall at room temperature for phosphate removal and extraction of chitosan from the phosphate free cell wall at high temperature, significantly reduces the chitosan molecular weight. This study was aimed at improvement of this method. In the pretreatment step, to choose the best conditions, cell wall of Rhizopus oryzae, containing 9% phosphate, 10% glucosamine, and 21% N-acetyl glucosamine, was treated with sulfuric, lactic, acetic, nitric, or hydrochloric acid, at room temperature. Sulfuric acid showed the best performance in phosphate removal (90%) and cell wall recovery (89%). To avoid depolymerisation of chitosan, hot sulfuric acid extraction was replaced with lactic acid treatment at room temperature, and a pure fungal chitosan was obtained (0.12 g/g cell wall). Similar pretreatment and extraction processes were conducted on pure shrimp chitosan and resulted in a chitosan recovery of higher than 87% while the reduction of chitosan viscosity was less than 15%. Therefore, the sulfuric-lactic acid method purified the fungal chitosan without significant molecular weight manipulation.

  11. Influence of various acids on the physico–mechanical properties of pozzolanic cement mortars

    Indian Academy of Sciences (India)

    S Türkel; B Felekoǧlu; S Dulluç

    2007-12-01

    Acidic attack represents a topic of increasing significance, owing to the spread of damages of concrete structures in both urban and industrial areas. Cement type is an important factor affecting performance of cement based materials in an aggressive environment. The goal of this study was to compare the acid resistance of a pozzolanic cement (CEM IV-A/32·5) with Portland cement (CEM I 32·5) that was made from the same clinker. For this purpose, 50 mm mortar cubes were prepared with two different kinds of cement according to TS EN 196-1. After 28 days of hardening, the samples were immersed into four different concentrations of hydrochloric, nitric and sulfuric acid solutions for a period of 120 days. The changes in weight loss and compressive strength values for each acid solution within the test period were recorded. The acid resistance of mortars made from Portland cement was better than the pozzolanic cement incorporated samples after 120 days of acid attack.

  12. Fatty acids - trans fatty acids

    Science.gov (United States)

    The data supporting a negative effect of dietary trans fatty acids on cardiovascular disease risk is consistent. The primary dietary sources of trans fatty acids include partially hydrogenated fat and rudiment fat. The adverse effect of trans fatty acids on plasma lipoprotein profiles is consisten...

  13. 酸改性沸石去除高浓度甲醛废水的研究%Removal Formaldehyde from High Concentration Wastewater by Acid Modified Zeolite

    Institute of Scientific and Technical Information of China (English)

    柯振刚; 祁翠翠

    2011-01-01

    The acid modified zeolite were prepared by hydrochloric acid and natural zeolite.The adsorption of acid modified zeolite to formaldehyde was studied through static experiments.The results indicated that when pH was 6.5,the statically saturated adsorption capacity was 255 mg/g at 293 K.It spent 2 h to reach adsorption equilibrium.%用盐酸对天然沸石进行改性得到酸改性沸石,通过静态吸附实验研究了酸改性沸石对废水中甲醛的吸附性能。研究表明在293 K时,酸改性沸石对甲醛的平衡吸附量为255 mg/g,最佳吸附pH值为6.5,吸附平衡时间为2 h。

  14. Green synthesis in acid water of 5,7,3’,4’-O-tetramethylquercetin

    Directory of Open Access Journals (Sweden)

    Zhong-lei WANG

    2014-04-01

    Full Text Available Objective: To synthesize 5,7,3′,4′-O-tetramethylrutin. Methods: With absolute N,N-dimethylformamide as the solvent, rutin and methyl iodide were stirring reaction at room temperature for 48h in the presence of potassium carbonate to obtain 5,7,3′,4′-O-tetramethylrutin, after filtering, rinsing with acetone and concentration under reduced pressure. The concentrate was heated and refluxed for about 1h in 0.50% hydrochloric acid, and then cooled and filtered. The precipitation was washed to neutral with distilled water. Results: The synthesis of 5,7,3′,4′-O-tetramethylquercetin was achieved through the steps above, and it has the same anti-influenza virus effect with oseltamivir, the yield was 92.2%. Conclusion: This method owns the characteristics of high yield, simple process, stable and feasible.

  15. Effect of cathodic charging on Al-32Si-2Cu alloy in acidic solution

    Directory of Open Access Journals (Sweden)

    Antonyraj Arockiasamy

    2010-09-01

    Full Text Available Samples of Al-32Si-2Cu intermetallic was subjected to electrochemical cathodic charging and corrosion test in hydrochloric acid (HCl solution of concentrations ranging from 0.1 to 3.0 M. The influence of cathodic charging current density and time on changing the surface morphology, phase transformation, compositions, and fracture mode has been investigated using X-ray diffraction (XRD and scanning electron microscope (SEM coupled with energy dispersive spectroscopy (EDS. A considerable drop in Vickers microhardness value with increasing cathodic charging time of the specimen was observed. Electrochemical polarization facilitates the formation of simple and mixed salt (AlCl3, Al5Cl3(OH12.2H2O over the alloy surface by chloride inclusion in the major corrosion product of hydroxides or oxides of Al.

  16. Amino Acid Composition of an Organic Brown Rice Protein Concentrate and Isolate Compared to Soy and Whey Concentrates and Isolates

    Directory of Open Access Journals (Sweden)

    Douglas S. Kalman

    2014-06-01

    Full Text Available A protein concentrate (Oryzatein-80™ and a protein isolate (Oryzatein-90™ from organic whole-grain brown rice were analyzed for their amino acid composition. Two samples from different batches of Oryzatein-90™ and one sample of Oryzatein-80™ were provided by Axiom Foods (Los Angeles, CA, USA. Preparation and analysis was carried out by Covance Laboratories (Madison, WI, USA. After hydrolysis in 6-N hydrochloric acid for 24 h at approximately 110 °C and further chemical stabilization, samples were analyzed by HPLC after pre-injection derivitization. Total amino acid content of both the isolate and the concentrate was approximately 78% by weight with 36% essential amino acids and 18% branched-chain amino acids. These results are similar to the profiles of raw and cooked brown rice except in the case of glutamic acid which was 3% lower in the isolate and concentrate. The amino acid content and profile of the Oryzatein-90™ isolate was similar to published values for soy protein isolate but the total, essential, and branched-chain amino acid content of whey protein isolate was 20%, 39% and 33% greater, respectively, than that of Oryzatein-90™. These results provide a valuable addition to the nutrient database of protein isolates and concentrates from cereal grains.

  17. Acidization of shales with calcite cemented fractures

    Science.gov (United States)

    Kwiatkowski, Kamil; Szymczak, Piotr; Jarosiński, Marek

    2017-04-01

    wormholes is the strongest when coating thickness is a few times larger than the initial aperture of the fracture. This leads to formation of favorable complex networks of wormholes which provide adequate transport of reactive fluids to fracture surfaces and - at the same time - are capable of supporting fracture surfaces. As a conclusion, acidization of the reactivated fractures with hydrochloric acid seems to be an attractive treatment to apply at fracking stage or later on as EGR. The results contribute to the discussion on the use of acidization to enhance the gas production in the shale reservoirs. This communication stresses the importance of the dissolution of calcite cement in natural fractures in shale formations, which are initially sealed and become reactivated during fracking. While this research is based on the analysis of fractures in the Pomeranian shale basin its results are general enough to be applicable to different formations worldwide.

  18. Evolution of water chemistry in natural acidic environments in Yangmingshan, Taiwan.

    Science.gov (United States)

    Ezoe, Yuka; Lin, Cheng-Huang; Noto, Masami; Watanabe, Yoshihiro; Yoshimura, Kazuhisa

    2002-08-01

    In Yangmingshan National Park, located in the northern part of the Taiwan Island, there is a very rare area where fish (Channa asiatica) live in spite of acid environments. The origin of the acid in local acid ponds and rivers and the evolution of the water chemistry are discussed on the basis of sulfur stable isotope ratios and chemical equilibria. One of the sources of the acid is sulfuric acid, which is derived from the oxidation of hydrogen sulfide in volcanic gas gushing out from fumaroles around the area and from acid deposition supplied from Taipei City. It is also derived from the oxidation of pyrite: the sulfur stable isotope ratios of delta 34S of +1@1000 to +4@1000 (relative to CDT) of sulfate in acid pond waters (pH 3-4) could be related to those of hydrogen sulfide in volcanic gas, pyrite in local pond sediments and soils, and sulfate in rain water. One acid source is sulfuric and hydrochloric acids arising in springs from geothermal activity: the delta 34S values were characterised by +13@1000 to +17@1000 sulfate-S, which was provided by a disproportionation reaction of sulfur dioxide in the depths. Another acid source could be the oxidation of iron(II). Under acidic conditions, the water-rock reaction gives rise to high concentrations of aluminium and iron. While flowing down surface streams, iron(II) is oxidised to iron(III) and then hydrolysed to cause further acidification under oxic conditions. The concentrations of iron and aluminium are controlled by redox and dissolution equilibria.

  19. Polymorphic transformation of antibiotic clarithromycin under acidic condition.

    Science.gov (United States)

    Noguchi, Shuji; Takiyama, Kei; Fujiki, Sadahiro; Iwao, Yasunori; Miura, Keiko; Itai, Shigeru

    2014-02-01

    Clarithromycin (CAM) is a 14-membered semisynthetic macrolide antibiotic used to treat the infection of various bacteria including Helicobacter pylori. The polymorphic transformation of CAM form II crystals under acidic conditions is, however, still unclear, and was investigated using X-ray powder diffraction method. Gel of CAM, which was immediately formed by mixing form II crystals with the hydrochloric acid solution, transformed at first to unstable form A crystals and then to form B crystals. Both forms A and B crystals are hydrochloride salts. Analyses using Hancock-Sharp equation revealed that the mechanism of form B formation was three-dimensional growth of nuclei. The rate constant of the transformation indicated that the times for 95% of form A transforming to form B at 37 °C are 0.69, 1.90, and 3.79 h at pH 1.5, 2.5, and 3.4, respectively. These suggest that the transformation from form II to form B via gel and form A could occur on the surface of form II formulation of prolonged gastric residence time, in the case that the pH in stomach stays low. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association.

  20. Glutamine Attenuates Acute Lung Injury Caused by Acid Aspiration

    Directory of Open Access Journals (Sweden)

    Chih-Cheng Lai

    2014-08-01

    Full Text Available Inadequate ventilator settings may cause overwhelming inflammatory responses associated with ventilator-induced lung injury (VILI in patients with acute respiratory distress syndrome (ARDS. Here, we examined potential benefits of glutamine (GLN on a two-hit model for VILI after acid aspiration-induced lung injury in rats. Rats were intratracheally challenged with hydrochloric acid as a first hit to induce lung inflammation, then randomly received intravenous GLN or lactated Ringer’s solution (vehicle control thirty min before different ventilator strategies. Rats were then randomized to receive mechanical ventilation as a second hit with a high tidal volume (TV of 15 mL/kg and zero positive end-expiratory pressure (PEEP or a low TV of 6 mL/kg with PEEP of 5 cm H2O. We evaluated lung oxygenation, inflammation, mechanics, and histology. After ventilator use for 4 h, high TV resulted in greater lung injury physiologic and biologic indices. Compared with vehicle treated rats, GLN administration attenuated lung injury, with improved oxygenation and static compliance, and decreased respiratory elastance, lung edema, extended lung destruction (lung injury scores and lung histology, neutrophil recruitment in the lung, and cytokine production. Thus, GLN administration improved the physiologic and biologic profiles of this experimental model of VILI based on the two-hit theory.

  1. Synthesis of (E)-9-Oxo-2-decenoic acid (the queen substance of honeybee) from methyl 3-formylpropionate; 3-horumiruporopion san mechiru wo mochiita (E)-9-okiso-2-desen san (Mitsubachi joo busshitsu) no gosei

    Energy Technology Data Exchange (ETDEWEB)

    Tsukasa, H. [Toyotama Koryo Co. Ltd., Tokyo (Japan)

    1997-05-20

    The queen substance, (E)-9-oxo-2-decenoic acid (1) is a pheromone secreted by queen honeybee (Apis mellifera) and inhibits reproductive ability of worker bees. Several synthesese have been reported. It was synthesized starting from methyl-3-formylpropionate this time. Methyl 7,7-ethylenedioxy-4-oxooctanoate was prepared by radical addition reaction from (2) and 2-methyl-2-vinyl-1,3-dioxolane and reduced to an ethyelenedioxy carboxylic acid with hydrazine and KOH. This compound was converted to an alcohol by reduction with sodium bis(2-methoxyethoxy)aluminum hydride, followed by oxidation with pyridinium chlorochromate to an acetal aldehyde, which was condensed with malonic acid and (1) was obtained after the hydrolysis with hydrochloric acid. 7 refs., 1 tab.

  2. Determination of Stability Constant of Neutral Amino Acid with Bjerrum's Half-integer Formation Function Method%半整数生成函数法测定中性氨基酸的稳定常数

    Institute of Scientific and Technical Information of China (English)

    张云; 王越; 房淑宁; 顾丽凤

    2013-01-01

    The method of Bjerrum's half-integer formation function and potentiometric titration was applied for determination of stability constants of eight kinds of neutral amino acids,including threonine, glycine,alanine,serine, valine, phenylalanine,leucine and isoleucine. The applied ways of titration include direct titrations by sodium hydroxide and hydrochloric acid, back titration by sodium hydroxide, as well as back titration by hydrochloric acid. The results were conformity with those reported in literature.%用电位滴定法作为实验手段,半整数生成函数法作为数据处理方法,分别采用氢氧化钠溶液和盐酸溶液直接滴定、氢氧化钠溶液返滴定、盐酸溶液返滴定等3种形式,对苏氨酸、甘氨酸、丙氨酸、丝氨酸、缬氨酸、苯丙氨酸、亮氨酸及异亮氨酸8种中性氨基酸的各级条件稳定常数进行了测定,所得结果与文献值吻合.

  3. Precipitation of sodium acid urate from electrolyte solutions

    Science.gov (United States)

    Füredi-Milhofer, Helga; Babić-Ivaniĉić, Vesna; Milat, Ognjen; Brown, Walter E.; Gregory, Thomas M.

    1987-07-01

    The precipitation of soduim urate from solutions containing uric acid, soduim hydroxide, hydrochloric acid, sodium chloride and water was investigated at constant pH (7.5±0.1) and temperature (308 K). Precipitates were observed by lights and electron microscopy and characterized by electron and X-ray diffraction. The results are presented in the form of "precipitation" and "chemical potential" diagrams, the latter giving the soduim-to-urate molar ratios of the precipitates. Two types of precipitation boundaries were observed, both of which had indicated soduim-to-urate moral ratios of 1:1. The ion activity product, (Na +)(HU -), associated with boundary I was AP I=(4.8±1.1)×10 -5 and with boundary II was with boundary II was AP II=(6.5±0.4)×10 -4. The supersaturation, S, at boundary II was S=AP II/ Ksp=12.3, in which Ksp is the solubility product of soduim acid urate monohydrate. The latter precipitated as well-formed crystals at supersaturations of 12.3 and above. The ion activity product associated with boundary I is approximately equal to the solubility product of soduim acid urate monohydrate. Small amounts of several morphologically different sodium urate crystals formed in the range of supersaturations (1≤ S≤12.3). Crystals formed in this range may include the monohydrate of sodium acid urate and possibly a higher hydrate. The findings have relevance to pathological renal stone formation and gouty arthritis.

  4. Quantification of glycated N-terminal peptide of hemoglobin using derivatization for multiple functional groups of amino acids followed by liquid chromatography/tandem mass spectrometry.

    Science.gov (United States)

    Sakaguchi, Yohei; Kinumi, Tomoya; Yamazaki, Taichi; Takatsu, Akiko

    2016-02-01

    A novel method of amino acid analysis using derivatization of multiple functional groups (amino, carboxyl, and phenolic hydroxyl groups) was applied to measure glycated amino acids in order to quantify glycated peptides and evaluate the degree of glycation of peptide. Amino and carboxyl groups of amino acids were derivatized with 1-bromobutane so that the hydrophobicities and basicities of the amino acids, including glycated amino acids, were improved. These derivatized amino acids could be detected with high sensitivity using LC-MS/MS. In this study, 1-deoxyfructosyl-VHLTPE and VHLTPE, which are N-terminal peptides of the β-chains of hemoglobin, were selected as target compounds. After reducing the peptide sample solution with sodium borohydride, the obtained peptides were hydrolyzed with hydrochloric acid. The released amino acids were then derivatized with 1-bromobutane and analyzed with LC-MS/MS. The derivatized amino acids, including glycated amino acids, could be separated using an octadecyl silylated silica column and good sharp peaks were detected. We show a confirmatory experiment that the proposed method can be applied to evaluate the degree of glycation of peptides, using mixtures of glycated and non-glycated peptide.

  5. 某化工厂废氯磺酸处置工艺设计实例%Engineering Example of Waste Chlorosulfonic Acid Treatment

    Institute of Scientific and Technical Information of China (English)

    马永飞

    2016-01-01

    江苏某化工厂现有废氯磺酸约100t,氯磺酸含量65.2%,难以直接利用,属危险废物,需安全处置。本文将废氯磺酸加入到90%的硫酸进行分解,在妥善处置氯磺酸的同时,可以副产盐酸、硫酸,实现了废酸的综合利用。%An chemical company in Jiangsu province has about 100 tons of waste chlorosulfonic acid now. The content of waste chlorosulfonic acid is 65. 2% . So the waste chlorosulfonic acid is difficult to be used directly. The waste chlorosulfonic acid is hazardous waste which need safe disposal. 90% sulfuric acid is used to decompose the waste chlorosulfonic acid. This method which can gain By - product sulfuric acid and By - product hydrochloric acid is a safe ultimate disposition protocol of waste chlorosulfonic acid. This method realized the comprehensive utilization of the waste chlorosulfonic acid.

  6. Simultaneous determination of acidic pesticides in vegetables and fruits by liquid chromatography--tandem mass spectrometry.

    Science.gov (United States)

    Shida, Shizuka S; Nemoto, Satoru; Matsuda, Rieko

    2015-01-01

    A sensitive and efficient method has been developed for the simultaneous determination of 73 multi-class acidic pesticides, such as phenoxy acid and sulfonylurea herbicides, in vegetables and fruits. The sample preparation procedure was carefully optimized for the efficient removal of co-extracted matrix components. The method involves extraction of acidic pesticides with acetonitrile containing hydrochloric acid, removal of water from crude extract by salting out, and sequential cleanup by octadecylsilyl silica gel and silica gel columns. For samples containing high amounts of pigments, such as spinach, additional cleanup using a graphitized carbon column was performed prior to liquid chromatography-mass spectrometry (LC-MS/MS) analysis. Recovery tests were performed for five times for each sample of cabbage, spinach, potato, eggplant, orange, and apple fortified at 0.01 mg kg-1. Out of the 73 tested pesticides, 70 for cabbage, 67 for spinach, 69 for potato, 67 for eggplant, 64 for orange, and 70 for apple were within the range of 70-120%, with relative standard deviations below 25%. Nitenpyram and pyrasulfotole showed low recoveries for all the samples tested, probably due to low recoveries from silica gel column. The developed method effectively removed co-extracted matrix components and was highly selective, with no interfering peaks found in the chromatograms of blank samples. The overall results indicate that the developed method is suitable for the quantitative analysis of acidic pesticide residues in vegetables and fruits.

  7. Kinetic modeling of cement slurry synthesized with Henna extract in oil well acidizing treatments

    Directory of Open Access Journals (Sweden)

    Amir Hossein Aghajafari

    2016-06-01

    Full Text Available Acidizing treatment in petroleum reservoirs is a short-term and viable strategy to preserve the productivity of a well. There is a major concern for the degradation of cement sheath integrity, leading to poor zonal isolation and environmental issues. Therefore, it is essential to understand how the cement behaves when attacked by hydrochloric acid. In this study, a cement slurry by incorporation of the Henna extract, as an environmentally friendly cement additive, was synthesized as a potential solution to solve this problem. The characteristics of the treated cement slurry were compared with a reference slurry (w/c = 0.44 which is composed of only cement and water. A kinetic study was carried out to evaluate the adsorption behavior of the cement slurries exposed to an acid solution with 0.1 M HCl in a range of 25 to 55 °C conditions. The features of the cement slurries were evaluated by multiple analytical techniques such as XRD, FTIR, TG, and DSC analysis. From the experimental data, it is concluded that the second-order Lagergren kinetic model revealed to be the best in describing kinetic isotherms taken, because the margin between experimental and calculated values was minor for this model. The results of the characterization and HCl interaction kinetic studies underlined the prominent protective role of Henna extract-modified cement slurry in the enhancement of the cement resistance against acid attack and utilization in environmentally favorable oil well acidizing treatments.

  8. Preparation of manganese sulfate from low-grade manganese carbonate ores by sulfuric acid leaching

    Institute of Scientific and Technical Information of China (English)

    Qing-quan Lin; Guo-hua Gu; Hui Wang; Ren-feng Zhu; You-cai Liu; and Jian-gang Fu

    2016-01-01

    In this study, a method for preparing pure manganese sulfate from low-grade ores with a granule mean size of 0.47 mm by direct acid leaching was developed. The effects of the types of leaching agents, sulfuric acid concentration, reaction temperature, and agitation rate on the leaching efficiency of manganese were investigated. We observed that sulfuric acid used as a leaching agent provides a similar leach-ing efficiency of manganese and superior selectivity against calcium compared to hydrochloric acid. The optimal leaching conditions in sul-furic acid media were determined; under the optimal conditions, the leaching efficiencies of Mn and Ca were 92.42% and 9.61%, respec-tively. Moreover, the kinetics of manganese leaching indicated that the leaching follows the diffusion-controlled model with an apparent ac-tivation energy of 12.28 kJ·mol−1. The purification conditions of the leaching solution were also discussed. The results show that manganese dioxide is a suitable oxidant of ferrous ions and sodium dimethyldithiocarbamate is an effective precipitant of heavy metals. Finally, through chemical analysis and X-ray diffraction analysis, the obtained product was determined to contain 98% of MnSO4·H2O.

  9. Co-production of functional xylooligosaccharides and fermentable sugars from corncob with effective acetic acid prehydrolysis.

    Science.gov (United States)

    Zhang, Hongyu; Xu, Yong; Yu, Shiyuan

    2017-06-01

    A novel and green approach for the coproduction of xylooligosaccharides (XOS), in terms of a series of oligosaccharide components from xylobiose to xylohexose, and fermentable sugars was developed using the prehydrolysis of acetic acid that was fully recyclable and environmentally friendly, followed by enzymatic hydrolysis. Compared to hydrochloric acid and sulfuric acid, acetic acid hydrolysis provided the highest XOS yield of 45.91% and the highest enzymatic hydrolysis yield. More than 91% conversion of cellulose was achieved in a batch-hydrolysis using only a cellulase loading of 20FPU/g cellulose and even a high solid loading of 20% without any special strategies. The acetic acid pretreated corncob should be washed adequately before saccharification to achieve complete hydrolysis. Consequently, a mass balance analysis showed that 139.8g XOS, 328.1g glucose, 25.1g cellobiose, and 147.8g xylose were produced from 1000g oven dried raw corncob. Copyright © 2017. Published by Elsevier Ltd.

  10. Mechanism and Kinetics for the Dissolution of Apatitic Materials in Acid Solutions

    Directory of Open Access Journals (Sweden)

    Calmanovici C.E.

    1997-01-01

    Full Text Available Abstract - This work concerns the study of the digestion step in the production process of phosphoric acid. Some qualitative experiments indicate that the difference between the pH at the surface of the phosphate and that in the bulk of the solution is negligible and that the dissolution is controlled by diffusion of products away from the phosphate particle. In further experiments, to isolate the dissolution phenomenon from the formation of calcium sulfate, the sulfuric acid normally used industrially is replaced by hydrochloric acid. The phosphate material used in our experiments is a model apatitic material: synthetic hydroxyapatite (HAP. The dissolution of calcium hydroxyapatite was studied with increasing amounts of calcium and phosphate at different temperatures. A simple method was developed for this observation based on the time required for complete dissolution of the HAP powder. The results confirm that the dissolution is controlled by a diffusional process through an interface of calcium and phosphate ions released from the solid surface. A kinetic model for the dissolution of apatitic materials is proposed which assumes a shrinking particle behaviour controlled by diffusion of calcium ions. The experimental results are fitted to this model to determine the mass transfer constant for HAP dissolution in acid solutions. The activation energy of the reaction is about 14kJ/mol. This study was carried on in conditions similar to the industrial ones for the production of phosphoric acid by the dihydrate-process

  11. Folic Acid

    Science.gov (United States)

    ... damage. 10 Do I need folic acid after menopause? Yes. Women who have gone through menopause still need 400 micrograms of folic acid every ... United States: 2003–2006 . American Journal of Clinical Nutrition; 91(1): 231–237. Hamner, H.C., Cogswell, ...

  12. [Evaluation on contribution rate of each component total salvianolic acids and characterization of apparent oil/water partition coefficient].

    Science.gov (United States)

    Yan, Hong-mei; Chen, Xiao-yun; Xia, Hai-jian; Liu, Dan; Jia, Xiao-bin; Zhang, Zhen-hai

    2015-02-01

    The difference between three representative components of total salvianolic acids in pharmacodynamic activity were compared by three different pharmacological experiments: HUVECs oxidative damage experiment, 4 items of blood coagulation in vitro experiment in rabbits and experimental myocardial ischemia in rats. And the effects of contribution rate of each component were calculated by multi index comprehensive evaluation method based on CRITIC weights. The contribution rates of salvianolic acid B, rosmarinic acid and Danshensu were 28.85%, 30.11%, 41.04%. Apparent oil/water partition coefficient of each representative components of total salvianolic acids in n-octyl alcohol-buffer was tested and the total salvianolic acid components were characterized based on a combination of the approach of self-defined weighting coefficient with effects of contribution rate. Apparent oil/water partition coefficient of total salvianolic acids was 0.32, 1.06, 0.89, 0.98, 0.90, 0.13, 0.02, 0.20, 0.56 when in octanol-water/pH 1.2 dilute hydrochloric acid solution/ pH 2.0, 2.5, 5.0, 5.8, 6.8, 7.4, 7.8 phosphate buffer solution. It provides a certain reference for the characterization of components.

  13. Bagasse hydrolyzates from Agave tequilana as substrates for succinic acid production by Actinobacillus succinogenes in batch and repeated batch reactor.

    Science.gov (United States)

    Corona-González, Rosa Isela; Varela-Almanza, Karla María; Arriola-Guevara, Enrique; Martínez-Gómez, Álvaro de Jesús; Pelayo-Ortiz, Carlos; Toriz, Guillermo

    2016-04-01

    The aim of this work was to obtain fermentable sugars by enzymatic or acid hydrolyses of Agave tequilana Weber bagasse in order to produce succinic acid with Actinobacillus succinogenes. Hydrolyses were carried out with mineral acids (sulfuric and hydrochloric acids) or a commercial cellulolytic enzyme, and were optimized statistically by a response surface methodology, having as factors the concentration of acid/enzyme and time of hydrolysis. The concentration of sugars obtained at optimal conditions for each hydrolysis were 21.7, 22.4y 19.8g/L for H2SO4, HCl and the enzymatic preparation respectively. Concerning succinic acid production, the enzymatic hydrolyzates resulted in the highest yield (0.446g/g) and productivity (0.57g/Lh) using A. succinogenes in a batch reactor system. Repeated batch fermentation with immobilized A. succinogenes in agar and with the enzymatic hydrolyzates resulted in a maximum concentration of succinic acid of 33.6g/L from 87.2g/L monosaccharides after 5 cycles in 40h, obtaining a productivity of 1.32g/Lh.

  14. DL-天冬氨酸的绿色合成%Green Synthesis and Characterization of DL-Aspartic Acid

    Institute of Scientific and Technical Information of China (English)

    崔建兰; 徐春彦; 曹端林

    2003-01-01

      The process of synthesizing DL-Aspartic acid with maleic acid and ammonia as raw materials was improved in this paper. It realizes the green synthesis at a low cost and less pollution, when maleic acid was used instead of traditional hydrochloric acid in the acidification process. The yield of DL-Aspartic acid was up to 75% above and purity 98.9%. The product DL-Aspartic acid was characterized by IR, the amino-acid automatic analyzing instrument, nuclear magnetic resonance.%  本文对以顺丁烯二酸与氨水为原料合成DL-天冬氨酸的方法进行了改进,在酸化后处理过程中,以顺丁烯二酸代替传统的盐酸,反应平均收率提高到75%以上,纯度达98.9%,实现了绿色合成,减少了污染,降低了成本,并通过红外光谱、核磁共振、氨基酸自动分析仪等对产品进行了表征.

  15. Food engineering residues: amino acid composition of hydrolysates and application for the decontamination of metal polluted soils

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, K. (GSF-Forschungszentrum, Inst. fuer Oekologische Chemie, Oberschleissheim (Germany) TU Muenchen, Lehrstuhl fuer Oekologische Chemie, Freising-Weihenstephan (Germany)); Riemschneider, P. (GSF-Forschungszentrum, Inst. fuer Oekologische Chemie, Oberschleissheim (Germany)); Bieniek, D. (GSF-Forschungszentrum, Inst. fuer Oekologische Chemie, Oberschleissheim (Germany)); Kettrup, A. (GSF-Forschungszentrum, Inst. fuer Oekologische Chemie, Oberschleissheim (Germany) TU Muenchen, Lehrstuhl fuer Oekologische Chemie, Freising-Weihenstephan (Germany))

    1994-11-01

    Several residues of the brewing industry and slaughtering offals were investigated in order to evaluate their potential as raw materials for the hydrolytic preparation of amino acid containing solutions, applicable as extractants in amelioration processes for metal polluted soils. The residues were hydrolysed with 6 mol/L hydrochloric acid and the hydrolysates were analysed for their total nitrogen, TOC, amino acid and heavy metal contents. Then, the leaching capacities of the hydrolysates were examined in a series of batch tests with a contaminated soil. High amino acid yields in relation to the weight of the air-dried raw materials were achieved with blood meal (72.5%) and poultry feather meal (56.6%). The portion of the detected amino acids of the total organic carbon content of the hydrolysates ranged from 38.9% (brewer's spent grain) to 93.6% (blood meal). In extraction tests with hydrolysates adjusted to a total amino acid concentration of 60 mmol/L and to a pH value of 7.0, maximum extraction yields of 50.3% for copper (soil content 279 mg kg[sup -1]) and 38.7% for nickel (soil content 54 mg kg[sup -1]) were reached. An increase of the hydrolysate concentration and of the pH of an amino acid mixture resulted in higher solubilisation of the metals. (orig.)

  16. Effects of Different Solvents on the Surface Acidic Oxygen-containing Functional Groups on Xanthoceras sorbifolia Shell

    Directory of Open Access Journals (Sweden)

    Linan Liu

    2014-03-01

    Full Text Available This study reports the preparation of a novel biomaterial from a forestry residue - Xanthoceras sorbifolia shell (XSS - by solvent modification. The effects of acid and base (hydrochloric acerbic, acetic acid, sodium hydroxide, ammonia water and some organic solvents (ethanol, acetone, ethyl acetate, chloroform, petroleum ether, and n-hexane on the surface acidic functional groups (SAFGs on XSS were investigated. The amount of SAFGs was quantified using acid and alkali chemical titration methods, and the characteristics of virgin XSS were compared with treated ones by FT-IR spectroscopy. It was found that acid solutions can increase the concentration of SAFGs, while alkaline solutions reduce it. The XSS treated in 0.5 M HCl has the largest number of total acidic functional groups and phenolic hydroxyl groups. The shell extracted with 2 M acetic acid has the highest concentration of carboxyl. The SAFG contents were remarkably increased by treatments with ethanol and acetone, due to the outstanding enhancement of phenolic hydroxyl. These changes in the SAFGs of XSS brought about by treatments with various solutions could be a theoretical foundation for modifying this residue to create a new type of highly efficient absorbent material.

  17. The Effects of Various Acid Catalyst on the Esterification of Jatropha Curcas Oil based Trimethylolpropane Ester as Biolubricant Base Stock

    Directory of Open Access Journals (Sweden)

    Noor Hafizah Arbain

    2011-01-01

    Full Text Available Biolubricant production of trimethylolpropane ester (ET was conducted via esterification of fatty acid (FA of Jatropha curcas oil with trimethylolpropane (TMP. The condition for this reaction was as follows: temperature was 150 °C, time of reaction was 3 hours, molar ratio of FA: TMP was 4:1 and 2% wt/wt concentrated catalyst (based on weight of FA. Different catalyst was used in this reaction such as perchloric acid, sulfuric acid, p-toluenesulfonic acid, hydrochloric acid and nitric acid. The composition of ET was determined by Gas Chromatography (GC-FID. The ester group was confirmed by Fourier Transform Infrared Spectroscopy (FTIR and the structure was confirmed by proton and carbon Nuclear Magnetic Resonance (1H-NMR and 13C-NMR spectra. 70% of ET was successfully synthesized using perchloric acid in this research. The pour point of the product was observed as low as –23 °C, flash point is >300 °C and viscosity index is 150.

  18. Acidic digestion in a teleost: postprandial and circadian pattern of gastric pH, pepsin activity, and pepsinogen and proton pump mRNAs expression.

    Directory of Open Access Journals (Sweden)

    Manuel Yúfera

    Full Text Available Two different modes for regulation of stomach acid secretion have been described in vertebrates. Some species exhibit a continuous acid secretion maintaining a low gastric pH during fasting. Others, as some teleosts, maintain a neutral gastric pH during fasting while the hydrochloric acid is released only after the ingestion of a meal. Those different patterns seem to be closely related to specific feeding habits. However, our recent observations suggest that this acidification pattern could be modified by changes in daily feeding frequency and time schedule. The aim of this study was to advance in understanding the regulation mechanisms of stomach digestion and pattern of acid secretion in teleost fish. We have examined the postprandial pattern of gastric pH, pepsin activity, and mRNA expression for pepsinogen and proton pump in white seabream juveniles maintained under a light/dark 12/12 hours cycle and receiving only one morning meal. The pepsin activity was analyzed according to the standard protocol buffering at pH 2 and using the actual pH measured in the stomach. The results show how the enzyme precursor is permanently available while the hydrochloric acid, which activates the zymogen fraction, is secreted just after the ingestion of food. Results also reveal that analytical protocol at pH 2 notably overestimates true pepsin activity in fish stomach. The expression of the mRNA encoding pepsinogen and proton pump exhibited almost parallel patterns, with notable increases during the darkness period and sharp decreases just before the morning meal. These results indicate that white seabream uses the resting hours for recovering the mRNA stock that will be quickly used during the feeding process. Our data clearly shows that both daily illumination pattern and feeding time are involved at different level in the regulation of the secretion of digestive juices.

  19. Diana Auth, Eva Buchholz, Stefanie Janczyk (Hg.: Selektive Emanzipation. Analysen zur Gleichstellungs- und Familienpolitik. Opladen u.a.: Verlag Barbara Budrich 2010.

    Directory of Open Access Journals (Sweden)

    Maria Wersig

    2010-07-01

    Full Text Available Im vorliegenden Sammelband wird die Gleichstellungs- und Familienpolitik der Großen Koalition aus feministisch-politikwissenschaftlichen Perspektiven analysiert. Die Beiträge geben einen Überblick über wichtige politische Entwicklungslinien der letzten Jahre und bieten kritische Perspektiven auf der Grundlage unterschiedlicher methodischer und theoretischer Zugänge. Im Zentrum stehen die Auswirkungen politischer Reformen auf unterschiedliche Gruppen von Frauen und Männern sowie Analysen der Bedeutung der Geschlechterverhältnisse im Zusammenwirken mit anderen Diskriminierungskategorien in politischen Prozessen. Ergänzt werden die Auseinandersetzungen mit dem deutschen Status quo durch drei Beiträge, welche europäische Entwicklungen in ihre Überlegungen einbeziehen.The collected volume at hand analyses equality and family politics of the Grand Coalition from the perspective of feminism and political science. The contributions provide an overview of the important political developments charted in recent years and offer critical perspectives that are based on different methodological and theoretical approaches. Central to the volume are the effects of political reforms on different groups of women and men as well as analyses of the meaning of gender relations in conjunction with other categories of discrimination in political processes. The volume expands on the examination of the German status quo in three contributions, which include also European developments in their considerations.

  20. Folic acid

    Science.gov (United States)

    ... taking a specific nutritional supplement, containing vitamin B3 (nicotinamide), a compound isolated from grains (azelaic acid), zinc, ... lung cancer in most people. A type of skin cancer called melanoma. Limited research suggests that taking ...

  1. Folic Acid

    Science.gov (United States)

    ... B-complex vitamin needed by the body to manufacture red blood cells. A deficiency of this vitamin ... prepared from dried yeast, fruit, and fresh leafy green vegetables to increase the folic acid in your ...

  2. Profiling Amino Acids of Jordanian Scalp Hair as a Tool for Diabetes Mellitus Diagnosis: A Pilot Study.

    Science.gov (United States)

    Rashaid, Ayat H B; Harrington, Peter de B; Jackson, Glen P

    2015-07-21

    Hair analysis is an area of increasing interest in the fields of medical and forensic sciences. Human scalp hair has attractive features in clinical studies because hair can be sampled easily and noninvasively from human subjects, and unlike blood and urine samples, it contains a chronological record of medication use. Keratin protein is the major component of scalp hair shaft material and it is composed of 21 amino acids. The method used herein for the amino acid determination in hair included keratin protein acid hydrolysis using 6 M hydrochloric acid (HCl), followed by amino acids derivatization using N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA), and the determination of derivatized amino acids by gas chromatography/mass spectrometry (GC/MS). Amino acid profiles of scalp hair of 27 Jordanian subjects (15 diabetes mellitus (DM) type 2 patients and 12 control subjects) were analyzed. A fuzzy rule-building expert system (FuRES) classified the amino acid profiles into diabetic and control groups based on multivariate analyses of the abundance of 14 amino acids. The sensitivity and specificity were 100% for diabetes detection using leave-one-individual-out cross-validation. The areas under the receiver operative characteristics (ROC) curves were 1.0, which represents a highly sensitive and specific diabetes test. The nonessential amino acids Gly and Glu, and the essential amino acid Ile were more abundant in the scalp hair of diabetic patients compared to the hair of control subjects. The associations between the abundance of amino acids of human hair and health status may have clinical applications in providing diagnostic indicator or predicting other chronic or acute diseases.

  3. Development and validation of dissolution testings in acidic media for rabeprazole sodium delayed-release capsules.

    Science.gov (United States)

    Tan, Yinhe; Si, Xiaoqing; Zhong, Lulu; Feng, Xin; Yang, Xinmin; Huang, Min; Wu, Chuanbin

    2016-10-01

    Rabeprazole sodium (RAB) dissolved in acidic media is accompanied by its degradation in the course of dissolution testing. To develop and establish the accumulative release profiles of ACIPHEX(®) Sprinkle (RAB) delayed-release capsules (ACIPHEX(®) Sprinkle) in acidic media using USP apparatus 2 (paddle apparatus) as a dissolution tester, the issues of determination of accumulative release amount of RAB in these acidic media and interference of hydroxypropylmethyl cellulose phthalate were solved by adding appropriate hydrochloric acid (HCl) into dissolution samples coupled with centrifugation so as to remove the interference and form a solution of degradation products of RAB, which is of a considerably stable ultraviolet (UV) absorbance at the wavelength of 298 nm within 2.0 h. Therefore, the accumulative release amount of RAB in dissolution samples at each sample time points could be determined by UV-spectrophotometry, and the accumulative release profiles of ACIPHEX(®) Sprinkle in the media of pH 1.0, pH 6.0, and pH 6.8 could be established. The method was validated per as the ICH Q2 (R1) guidelines and demonstrated to be adequate for quality control of ACIPHEX(®) Sprinkle and the accumulative release profiles can be used as a tool to guide the formulation development and quality control of a generic drug for ACIPHEX(®) Sprinkle.

  4. Application of acid-catalyzed hydrolysis of dispersed organic solvent in developing new microencapsulation process technology.

    Science.gov (United States)

    Lee, Honghwa; Lee, Sunhwa; Bhattacharjee, Himanshu; Sah, Hongkee

    2012-01-01

    The aim of this study was to evaluate a new microencapsulation technology employing an acid-catalyzed solvent extraction method in conjunction to an emulsion-based microencapsulation process. Its process consisted of emulsifying a dispersed phase of poly(D,L-lactide-co-glycolide) and isopropyl formate in an aqueous phase. This step was followed by adding hydrochloric acid to the resulting oil-in-water emulsion, in order to initiate the hydrolysis of isopropyl formate dissolved in the aqueous phase. Its hydrolysis caused the liberation of water-soluble species, that is, isopropanol and formic acid. This event triggered continual solvent leaching out of emulsion droplets, thereby initiating microsphere solidification. This new processing worked well for encapsulation of progesterone and ketoprofen that were chosen as a nonionizable model drug and a weakly acidic one, respectively. Furthermore, the structural integrity of poly(D,L-lactide-co-glycolide) was retained during microencapsulation. The new microencapsulation technology, being conceptually different from previous approaches, might be useful in preparing various polymeric particles.

  5. Durability improvement assessment in different high strength bacterial structural concrete grades against different types of acids

    Indian Academy of Sciences (India)

    Ramin Andalib; M Zaimi Abd Majid; A Keyvanfar; Amirreza Talaiekhozan; Mohd Warid Hussin; A Shafaghat; Rosli Mohd Zin; Chew Tin Lee; Mohammad Ali Fulazzaky; Hasrul Haidar Ismail

    2014-12-01

    This paper provides an insight into a new biotechnological method based on calcite precipitation for achieving high strength bio-concrete durability. It is very clear that mineral precipitation has the potential to enhance construction material resistance towards degradation procedures. The appropriate microbial cell concentration (30 * 105 cells/ml) was introduced onto different structural concrete grades (40, 45 and 50 MPa) by mixing water. In order to study the durability of structural concrete against aggressive agents, specimens were immersed in different types of acids solution (5% H2SO4 and HCl) to compare their effects on 60th, 90th and 120th day. In general, sulphuric acid and hydrochloric acid are known to be the most aggressive natural threats from industrial waters which can penetrate concrete to transfer the soluble calcium salts away from the cement matrix. The experimental results demonstrated that bio-concrete has less weight and strength losses when compared to the ordinary Portland cement concrete without microorganism. It was also found that maximum compressive strength and weight loss occurred during H2SO4 acid immersion as compared to HCl immersion. The density and uniformity of bio-concrete were examined using ultrasonic pulse velocity (UPV) test. Microstructure chemical analysis was also quantified by energy dispersive spectrometer (EDS) to justify the durability improvement in bacterial concrete. It was observed that less sulphur and chloride were noticed in bacterial concrete against H2SO4 and HCl, respectively in comparison to the ordinary Portland cement concrete due to calcite deposition.

  6. EFFECTS OF SURFACTANT AND ACID TYPE ON PREPARATION OF CHITOSAN MICROCAPSULES

    Institute of Scientific and Technical Information of China (English)

    Zhenqiu Yang; Baozhen Song; Qiaoxia Li; Honglei Fan; Fan Ouyang

    2004-01-01

    Chitosan microcapsules were prepared by a method involving emulsification and crosslinking. The effects of surfactants and acid type for dissolving chitosan on the characteristics of chitosan microcapsules were investigated.The results showed that the mixed surfactant consisting of Span80 and Tween60 had an obvious effect on reducing the size of the microcapsules. The two-surfactant complex, formed on the basis of hydrogen bonding, strengthened the interfacial membrane in the emulsion, thus decreasing not only the size of the microcapsules but also the coalescence of dispersed chitosan liquid drops. In the case of monoacid such as hydrochloric acid or acetic acid for dissolving chitosan,the chitosan microcapsules obtained were spherical in shape with smooth surfaces. For diacids or triacid, the chitosan microcapsules obtained were also spherical, but their surfaces were covered by folds and crinkles. The number of carboxyl groups in the acids used influenced the chemical crosslinking between chitosan and the crosslinker (glutaraldehyde) as well as the morphology of the particles. For diacids or triacid, physical crosslinking occured due to electrostatic force, accompanied by substantial decrease of covalent crosslinking, leading to decreased strength of the microcapsules as shown by the collapse of microcapsule walls and the formation of multiple folds and crinkles on their surfaces.

  7. Determination of herbicides paraquat, glyphosate, and aminomethylphosphonic acid in marijuana samples by capillary electrophoresis.

    Science.gov (United States)

    Lanaro, Rafael; Costa, José L; Cazenave, Silvia O S; Zanolli-Filho, Luiz A; Tavares, Marina F M; Chasin, Alice A M

    2015-01-01

    In this work, two methods were developed to determine herbicides paraquat, glyphosate, and aminomethylphosphonic acid (AMPA) in marijuana samples by capillary electrophoresis. For paraquat analysis, sample was extracted with aqueous acetic acid solution and analyzed by capillary zone electrophoresis with direct UV detection. The running electrolyte was 50 mmol/L phosphate buffer (pH 2.50). For glyphosate and AMPA, indirect UV/VIS detection was used, as these substances do not present chromophoric groups. Samples were extracted with 5 mmol/L hydrochloric acid. The running electrolyte was 10 mmol/L gallic acid, 6 mmol/L TRIS, and 0.1 mmol/L CTAB (pH = 4.7). The methods presented good linearity, precision, accuracy, and recovery. Paraquat was detected in 12 samples (n = 130), ranging from 0.01 to 25.1 mg/g. Three samples were positive for glyphosate (0.15-0.75 mg/g), and one sample presented AMPA as well. Experimental studies are suggested to evaluate the risks of these concentrations to marijuana user.

  8. Preparation of a Novel Acid Doped Polyaniline Adsorbent for Removal of Anionic Pollutant from Wastewater

    Institute of Scientific and Technical Information of China (English)

    LI Jiajia; WANG Qizhao; BAI Yan; JIA Yongming; SHANG Pan; HUANG Haohao; WANG Fangping

    2015-01-01

    Polyaniline (PANI) was one of the most extensively studied adsorbents due to its low cost and good environmental stability. The objective of the current study was to improve the selective capabilities of PANI for anionic dyes. We found that the acid doped PANI prepared with hydrochloric acid and p-toluenesulfonic acid (PTSA) could selectively adsorb anionic dyes. It exhibited very good selectivity for OG dye, the mechanism was proposed based on the chemical interaction of PANI with the sulfonate group of the dyes. The effects of solution pH, initial dye concentration, and different HCl/PTSA mole ratios on the adsorption capacity of OG have been investigated. Kinetic simulations indicated that the adsorption process could be well represented by pseudo-second-order kinetic plots. The isothermal adsorption curve iftting also showed that the adsorption process could be well described by the Langmuir isothermal equation. The results showed that acid doped PANI could be employed as a promising adsorbent for anion removal from dye wastewater.

  9. Durability to Chemical Attack by Acids of Epoxy Microconcretes by Comparison to Cementitious Ones

    Directory of Open Access Journals (Sweden)

    Elhem Ghorbel

    2016-01-01

    Full Text Available This research deals with the durability of micropolymer concrete (MPC obtained by mixing an epoxy resin with fine and coarse sand particles. In particular the resistance of the micropolymer concrete to chemical solutions (citric acid C6H8O7, sulfuric acid H2SO4, and hydrochloric acid HCl is investigated and compared to this of Portland cement microconcrete. Two MPC are tested. The first is formulated with 9% mass fraction of epoxy polymer whereas calcareous fillers have been incorporated in the second formulation in order to reduce the percentage of the epoxy binder. It is shown that a microconcrete designed with 7% of epoxy, 10% of fillers, and 83% of aggregates is characterized by higher physical and mechanical properties than those of the MPC formulated with 9% of epoxy binder. The mechanical properties of the resulting materials after their exposure to the three selected acid solutions at different durations were studied through compressive, three points bending and ultrasonic wave propagation tests. The obtained results are compared to those of microcement concretes (MCC tested under the same conditions as MPC. The results show that both microepoxy polymer concretes exhibit better mechanical properties and highest resistance to chemical attack than the microcement concrete.

  10. Rare earth extraction from wet process phosphoric acid by emulsion liquid membrane

    Institute of Scientific and Technical Information of China (English)

    张利昌; 陈前林; 康超; 马昕; 杨尊良

    2016-01-01

    The recovery of rare earths (RE) during the wet processing of phosphoric acid is very important, the method of emul-sion liquid membrane (ELM) with di(2-ethylhexly) phosphate (D2EHPA) as carrier has the high selectivity while cannot provide a satisfactory extraction rate. Here novel method of emulsion liquid membrane (ELM) using Aniline as carrier to extract RE from the feed solution was proposed. The method could increase the extraction rate of RE in the real sample to 93%. The effects of dif-ferent parameters such as type and concentration of carrier and surfactant, hydrochloric acid concentration, organic to internal phase volume ratio, membrane to external phase volume ratio on extraction of RE3+ were investigated. Quantitative extraction (>93%) of RE3+ was observed with 6 vol.% Aniline and 4 vol.% T154 liquid membrane at external to internal phase volume ratio of 10 for the feed solution. The proposed method of ELM using Aniline as carrier can be expected to provide a practical, efficient, and economical method for extracting RE from phosphate leach solution with high acidity in the industry of wet process phospho-ric acid.

  11. Corrosion resistance of the composite materials: nanocrystalline powder – polymer type in acid environment

    Directory of Open Access Journals (Sweden)

    B. Ziębowicz

    2009-10-01

    Full Text Available Purpose: The paper presents corrosion resistance of composite materials Fe73.5Cu1Nb3Si13.5B9 – PEHD type in sulphuric acid and hydrochloric acid environments.Design/methodology/approach: Composite materials Fe73.5Cu1Nb3Si13.5B9 – PEHD type were manufactured by one-sided uniaxal pressing. The amount of polymer matrix was 2.5%, 5.0%, 7.5%, wt. Powder of the Fe73.5Cu1Nb3Si13.5B9 was made by the high-energy grinding in the shaker type 8000SPEX CertiPrep Mixer/Mill for 1 h, 3 h, 5 h. Composite materials were placed in a corrosive environment and two tests were carried out as specified below: test at the temperature of 25°C, 0.1 M solution of hydrochloric acid HCl, time 348 h; test temperature 25°C, 0.1 M solution of sulphuric acid H2SO4, time 348 h, test temperature 25°C.Findings: Obtained results of corrosion resistance allow to evaluate corrosion wear of composite materials FINEMET (Fe73.5Cu1Nb3Si13.5B9 – PEHD in acidic solutions of 0.1M HCl and 0.1M H2SO4. It was found that the composite materials with 7.5% wt. of polyethylene portion show the best corrosion resistance.Research limitations/implications: Composite materials Fe73.5Cu1Nb3Si13.5B9– PEHD type manufacturing greatly expand the application possibilities of soft magnetic materials nanocrystalline powders however further examination to obtain improved properties of magnetic composite materials and investigations of new machines and devices constructions with these materials elements are still needed.Originality/value: Results allow to complete data concerning composite materials nanocrystalline powder – polymer type which are an attractive alternative for traditional materials with specific magnetic properties. Results are the base for further investigations of the impact of corrosion environment on the magnetic properties such composite materials.

  12. Ibotenic acid and thioibotenic acid

    DEFF Research Database (Denmark)

    Hermit, Mette B; Greenwood, Jeremy R; Nielsen, Birgitte

    2004-01-01

    with the conformations preferred by the ligands upon docking to mGlu1 and models of the other mGlu subtypes, we propose that unlike other subtypes, group III mGlu receptor binding sites require a ligand conformation at an energy level which is prohibitively expensive for ibotenic acid, but not for thioibotenic acid....... These studies demonstrate how subtle differences in chemical structures can result in profound differences in pharmacological activity....

  13. Inhibition of acidic corrosion of carbon steel by some mono and bis azo dyes based on 1,5 dihydroxynaphihalene.

    Science.gov (United States)

    Abdallah, Metwally; Moustafa, Moustafa E

    2004-01-01

    Inhibition of the corrosion of carbon steel in hydrochloric acid solution by some mono- and bis-azo dyes based on 1,5-dihydroxynaphthalene was studied in relation to the concentration of inhibitors using weight loss and potentiostatic polarization techniques. The percentage inhibition efficiency calculated from two methods is in a good agreement with each other. The inhibition mechanism of the additives was ascribed to the formation of complex compound adsorbed on the metal surface. The adsorption process follows Freundlich adsorption isotherm. The formation of the complex compound was studied by conductometric and potentiometric titrations. The stability constants of the Fe-complexes were determined using the latter technique and related to the inhibition efficiency.

  14. Kinetics of Corrosion Inhibition of Aluminum in Acidic Media by Water-Soluble Natural Polymeric Pectates as Anionic Polyelectrolyte Inhibitors

    Directory of Open Access Journals (Sweden)

    Refat M. Hassan

    2013-06-01

    Full Text Available Corrosion inhibition of aluminum (Al in hydrochloric acid by anionic polyeletrolyte pectates (PEC as a water-soluble natural polymer polysaccharide has been studied using both gasometric and weight loss techniques. The results drawn from these two techniques are comparable and exhibit negligible differences. The inhibition efficiency was found to increase with increasing inhibitor concentration and decrease with increasing temperature. The inhibition action of PEC on Al metal surface was found to obey the Freundlich isotherm. Factors such as the concentration and geometrical structure of the inhibitor, concentration of the corrosive medium, and temperature affecting the corrosion rates were examined. The kinetic parameters were evaluated and a suitable corrosion mechanism consistent with the kinetic results is discussed in the paper.

  15. Study and analysis of two semi-humid flue acid gas industrial treatment processes and study of an adsorption process of gaseous mercury on active carbon; Etude et analyse de deux dispositifs industriels de traitement d'effluents gazeux acide par voie semi-humide et etude d'un procede d'elimination du mercure gazeux par adsorption sur charbon actif

    Energy Technology Data Exchange (ETDEWEB)

    Anki, F.

    1998-07-01

    During the process of waste incineration, gaseous pollutants contained in fumes such as hydrochloric acid or mercury have to be removed before being discharged in air. A study has then been conducted on incineration plant fumes (municipal and industrial wastes). Four alkaline reagents have been tested in two semi-humid fume treatment processes for neutralizing hydrochloric acid. The reagents are: hydrated lime, sodium hydroxide, sodium bicarbonate and sodium carbonate. The alkaline solutions, pulverized in thin droplets, absorb and neutralize thus HCl and lead to the formation of a solid residue. On the other hand, a study of the adsorption of gaseous mercury on a coconut-based activated carbon has been conducted with a pilot fixed bed reactor. The taken incineration fume (flow rate: 2000 L/H) is introduced in the reactor at temperatures between 150 and 200 degrees Celsius. Different exposure times are tested to determine the saturation of the activated carbon by mercury. An evaporation model and an absorption model are applied; they represent the experimental evolution of the HCl absorption rates in terms of the liquid flow or of the stoichiometric factor. A model of mercury adsorption by the activated carbon is applied for determining the total transfer coefficient and the adsorption equilibrium constant. (O.M.)

  16. Impact of acid and alkaline pretreatments on the molecular network of wheat gluten and on the mechanical properties of compression-molded glassy wheat gluten bioplastics.

    Science.gov (United States)

    Jansens, Koen J A; Lagrain, Bert; Brijs, Kristof; Goderis, Bart; Smet, Mario; Delcour, Jan A

    2013-10-02

    Wheat gluten can be converted into rigid biobased materials by high-temperature compression molding at low moisture contents. During molding, a cross-linked protein network is formed. This study investigated the effect of mixing gluten with acid/alkali in 70% ethanol at ambient temperature for 16 h followed by ethanol removal, freeze-drying, and compression molding at 130 and 150 °C on network formation and on types of cross-links formed. Alkaline pretreatment (0-100 mmol/L sodium hydroxide or 25 mmol/L potassium hydroxide) strongly affected gluten cross-linking, whereas acid pretreatment (0-25 mmol/L sulfuric acid or 25 mmol/L hydrochloric acid) had limited effect on the gluten network. Molded alkaline-treated gluten showed enhanced cross-linking but also degradation when treated with high alkali concentrations, whereas acid treatment reduced gluten cross-linking. β-Elimination of cystine and lanthionine formation occurred more pronouncedly at higher alkali concentrations. In contrast, formation of disulfide and nondisulfide cross-links during molding was hindered in acid-pretreated gluten. Bioplastic strength was higher for alkali than for acid-pretreated samples, whereas the flexural modulus was only slightly affected by either alkaline or acid pretreatment. Apparently, the ratio of disulfide to nondisulfide cross-links did not affect the mechanical properties of rigid gluten materials.

  17. Acid Rain

    Science.gov (United States)

    Bricker, Owen P.; Rice, Karen C.; Dietrich, W.E.; Sposito, Garrison

    1997-01-01

    Acid deposition, or acid rain as it is more commonly referred to, has become a widely publicized environmental issue in the U.S. over the past decade. The term usually conjures up images of fish kills, dying forests, "dead" lakes, and damage to monuments and other historic artifacts. The primary cause of acid deposition is emission of S02 and NOx to the atmosphere during the combustion of fossil fuels. Oxidation of these compounds in the atmosphere forms strong acids - H2SO4 and HNO3 - which are returned to the Earth in rain, snow, fog, cloud water, and as dry deposition.Although acid deposition has only recently been recognized as an environmental problem in the U.S., it is not a new phenomenon (Cogbill & Likens 1974). As early as the middle of the 17th century in England, the deleterious effects of industrial emissions on plants, animals, and humans, and the atmospheric transport of pollutants between England and France had become issues of concern (Evelyn 1661, Graunt 1662). It is interesting that well over three hundred years ago in England, recommendations were made to move industry outside of towns and build higher chimneys to spread the pollution into "distant parts." Increasing the height of smokestacks has helped alleviate local problems, but has exacerbated others. In the U.S. the height of the tallest smokestack has more than doubled, and the average height of smokestacks has tripled since the 1950s (Patrick et al 1981). This trend occurred in most industrialized nations during the 20th century and has had the effect of transforming acid rain from a local urban problem into a problem of global scale.

  18. Vitamin B2 content determination in liver paste by using acid and acid-enzyme hydrolysis

    Directory of Open Access Journals (Sweden)

    Basić Zorica

    2007-01-01

    Full Text Available Background/Aim. Vitamin B2 is available in foodstuff in the form of coenzyme and in free form. For its content determination a few procedures should be performed (deliberation from a complex, extraction of free and deliberated form and detection, identification and quantification. There is a particular problem in determination of vitamin B2 in the meat products. For a determination of total vitamin B2 content in liver paste two preparation procedures are compared: acid and acid-enzymatic hydrolysis. The aim of this study thus, was to compare the effectiveness of these two different procedures for vitamin B2 content determination in liver paste. Methods. High pressure liquid chromatography (HPLC method with fluorescence detector, as specific and adequately sensitive for the foodstuff of a complex composition with a natural vitamin content, was used for determination of vitamin B2 in liver paste. Acid hydrolysis was performed with the application 0.1 M hydrochloric acid in a pressure cooker, and enzymatic hydrolysis was performed with the 10% takadiastase on 45 ºC within four hours. Ten samples of liver paste from the supply of the Serbian Army were examined. Separation was performed on the analytical column Nucleosil 50−5 C18 with mobile phase 450 ml CH3OH + 20 ml 5 mM CH3COONH4, and detection on the fluorescent detector with the variable wave length. Both methods were validated: examining a detection limit, quantification limit, specificity (because of a possible B2 vitamin interference with reagents, linearity of a peak area and standard concentration of B2 vitamin ratio in the range from 0.05 μg/ml to 2 μg/ml, precision for the 0.05 μg/ml concentration and recovery. Results. All the previously examined parameters validated both methods as specific, precise and reproductive, with a high recovery (98.5% for acid and 98.2% for acid - enzymatic hydrolysis, as well as linearity in a range that significantly superseded the expected content in

  19. Simultaneous determination of arsenic, cadmium, calcium, chromium, cobalt, copper, iron, lead, magnesium, manganese, molybdenum, nickel, selenium, and zinc in fertilizers by microwave acid digestion and inductively coupled plasma-optical emission spectrometry detection: single-laboratory validation of a modification and extension of AOAC 2006.03.

    Science.gov (United States)

    Webb, Sharon; Bartos, James; Boles, Rhonda; Hasty, Elaine; Thuotte, Ethel; Thiex, Nancy J

    2014-01-01

    A single-laboratory validation study was conducted for the simultaneous determination of arsenic, cadmium, calcium, cobalt, copper, chromium, iron, lead, magnesium, manganese, molybdenum, nickel, selenium, and zinc in all major types of commercial fertilizer products by microwave digestion and inductively coupled plasma-optical emission spectroscopy analysis. This validation study proposes an extension and modification of AOAC 2006.03. The extension is the inclusion of calcium, copper, iron, magnesium, manganese, and zinc, and the modification is incorporation of hydrochloric acid in the digestion system. This dual acid digestion utilizes both hydrochloric and nitric acids in a 3 to 9 mL volume ratio/100 mL. In addition to 15 of the 30 original validation materials used in the 2006.03 collaborative study, National Institute of Standards and Technology Standard Reference Material 695 and Magruder 2009-06 were incorporated as accuracy materials. The main benefits of this proposed method are a significant increase in laboratory efficiency when compared to the use of both AOAC Methods 965.09 and 2006.03 to achieve the same objective and an enhanced recovery of several metals.

  20. Perfluorooctanoic acid

    NARCIS (Netherlands)

    de Voogt, P.; Wexler, P.

    2014-01-01

    Perfluorooctanoic acid (PFOA, 335-67-1) is used in fluoropolymer production and firefighting foams and persists in the environment. Human exposure to PFOA is mostly through the diet. PFOA primarily affects the liver and can cause developmental and reproductive toxic effects in test animals.