WorldWideScience

Sample records for quaternary ammonium salts

  1. Synthesis of Chitosan Quaternary Ammonium Salts

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A series of N-alkyl or N-aryl chitosan quaternary ammonium salts were prepared via Schiffs base intermediates. Quaternization of N-substituted chitosan derivatives was carried out using methyl iodide to produce water-soluble cationic chitosan quaternary ammonium salt. The products were characterized by IR, 1HNMR and elemental analysis. The degree of substitution of chitosan quaternary ammonium salt was calculated by elemental analysis.

  2. Antimicrobial Polymeric Materials with Quaternary Ammonium and Phosphonium Salts

    Directory of Open Access Journals (Sweden)

    Yan Xue

    2015-02-01

    Full Text Available Polymeric materials containing quaternary ammonium and/or phosphonium salts have been extensively studied and applied to a variety of antimicrobial-relevant areas. With various architectures, polymeric quaternary ammonium/phosphonium salts were prepared using different approaches, exhibiting different antimicrobial activities and potential applications. This review focuses on the state of the art of antimicrobial polymers with quaternary ammonium/phosphonium salts. In particular, it discusses the structure and synthesis method, mechanisms of antimicrobial action, and the comparison of antimicrobial performance between these two kinds of polymers.

  3. Mutagenicity of quaternary ammonium salts containing carbohydrate moieties

    Energy Technology Data Exchange (ETDEWEB)

    Dmochowska, Barbara [Department of Carbohydrate Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Piosik, Jacek; Woziwodzka, Anna [Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Kladki 24, 80-822 Gdansk (Poland); Sikora, Karol; Wisniewski, Andrzej [Department of Carbohydrate Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Wegrzyn, Grzegorz, E-mail: wegrzyn@biotech.univ.gda.pl [Department of Molecular Biology, University of Gdansk, Kladki 24, 80-822 Gdansk (Poland)

    2011-10-15

    Highlights: {yields} A series of quaternary ammonium salts containing carbohydrate moieties, with configuration D-galacto, D-gluco and D-manno, was synthesized and characterized. {yields} The quaternary ammonium salts containing carbohydrate moieties revealed potent mutagenic activities, as assessed by using the Vibrio harveyi bioluminescence mutagenicity test. {yields} The N-[2-(D-glycopyranosyloxy)ethyl]-N,N,N-trimethylaminium salts were of the highest activity in the mutagenicity assay. {yields} We suggest that quaternary ammonium salts may be more hazardous than previously supposed. - Abstract: Quaternary ammonium salts are widely used in industrial, agricultural, healthcare and domestic applications. They are believed to be safe compounds, with little or no health hazard to humans. However, in this report, we demonstrate that a series of newly synthesized quaternary ammonium salts containing carbohydrate moieties reveal potent mutagenic activities, as assessed by using the Vibrio harveyi bioluminescence mutagenicity test. D-Gluco- and D-galacto-derivatives were found to have a higher mutagenic potential than D-manno-derivatives. Among the former groups of compounds, the N-[2-(D-glycopyranosyloxy)ethyl]-N,N,N-trimethylaminium salts were of the highest activity in the mutagenicity assay. These results suggest that the safety of quaternary ammonium salts may be lower than previously supposed, indicating a need for testing such compounds for their mutagenicity.

  4. The biological activity of quaternary ammonium salts (QASs

    Directory of Open Access Journals (Sweden)

    Ewa Obłąk

    2010-04-01

    Full Text Available Quaternary ammonium salts (QASs, especially those of cationic surfactant character, are applied as antibacterial and antifungal disinfectants. QASs affect lipid-enveloped viruses, including human immunodeficiency virus (HIV and hepatitis B virus (HBV, but not non-enveloped viruses. These compounds are extensively used in domestic (as ingredients of shampoos, hair conditioners, agricultural (as fungicides, pesticides, insecticides, healthcare (as medications, and industrial applications (as biocides, fabric softeners, corrosion inhibitors. The extensive use of quaternary ammonium disinfectants in recent years has led to the development of resistance in microorganisms to these drugs. Thus [i]Staphylococcus[/i] [i]aureus[/i] strains contain the plasmid-carrying genes [i]qacA[/i] and [i]qacB [/i]encoding resistance to quaternary ammonium compounds and acriflavine. The membrane proteins QacA and QacB confer multidrug resistance by exporting the compound by the proton motive force which is generated by the transmembrane electrochemical proton gradient.

  5. [The biological activity of quaternary ammonium salts (QASs)].

    Science.gov (United States)

    Obłak, Ewa; Gamian, Andrzej

    2010-04-19

    Quaternary ammonium salts (QASs), especially those of cationic surfactant character, are applied as antibacterial and antifungal disinfectants. QASs affect lipid-enveloped viruses, including human immunodeficiency virus (HIV) and hepatitis B virus (HBV), but not non-enveloped viruses. These compounds are extensively used in domestic (as ingredients of shampoos, hair conditioners), agricultural (as fungicides, pesticides, insecticides), healthcare (as medications), and industrial applications (as biocides, fabric softeners, corrosion inhibitors). The extensive use of quaternary ammonium disinfectants in recent years has led to the development of resistance in microorganisms to these drugs. Thus Staphylococcus aureus strains contain the plasmid-carrying genes qacA and qacB encoding resistance to quaternary ammonium compounds and acriflavine. The membrane proteins QacA and QacB confer multidrug resistance by exporting the compound by the proton motive force which is generated by the transmembrane electrochemical proton gradient.

  6. Mutagenic activity of quaternary ammonium salt derivatives of carbohydrates

    Science.gov (United States)

    Sikora, Karol; Woziwodzka, Anna; Piosik, Jacek; Podgórska, Beata

    2016-01-01

    Summary This paper presents a study on a series of quaternary ammonium salt (QAS) derivatives of glucopyranosides with an elongated hydrophobic hydrocarbon chain. The new N-[6-(β-D-glucopyranosyloxy)hexyl]ammonium bromides and their O-acetyl derivatives were analyzed via 1H and 13C NMR spectroscopy. The mutagenic activity of the newly synthesized QAS was investigated using two different techniques: The Vibrio harveyi luminescence assay and the Ames test. The obtained results support previous findings contesting QAS safety and indicate that QAS, specifically pyridinium derivatives, might be mutagenic. PMID:27559394

  7. Mutagenic activity of quaternary ammonium salt derivatives of carbohydrates

    Directory of Open Access Journals (Sweden)

    Barbara Dmochowska

    2016-07-01

    Full Text Available This paper presents a study on a series of quaternary ammonium salt (QAS derivatives of glucopyranosides with an elongated hydrophobic hydrocarbon chain. The new N-[6-(β-D-glucopyranosyloxyhexyl]ammonium bromides and their O-acetyl derivatives were analyzed via 1H and 13C NMR spectroscopy. The mutagenic activity of the newly synthesized QAS was investigated using two different techniques: The Vibrio harveyi luminescence assay and the Ames test. The obtained results support previous findings contesting QAS safety and indicate that QAS, specifically pyridinium derivatives, might be mutagenic.

  8. Studies on a Cationically Modified Quaternary Ammonium Salt of Lignin

    Institute of Scientific and Technical Information of China (English)

    YANG Ai-li; JIANG Wen-ju

    2007-01-01

    A new quaternary ammonium salt monomer was synthesized and a quaternary amination of lignin( noted as QL),with the monomer was carried out by grafting copolymerization. The products were characterized by Fourier Transform Infrared spectroscopy(FTIR). The experimental results indicate that the yield of the monomer was 99.06%, and the conversion of the monomer and the grafting yield of QL were 93.69% and 185.78%, respectively. The feasibility of QL as the fiocculant to be applied in color removal of five artificial dyes, eriochrome black T( dye A), gongo red( dye B), direct fast black G (dye C), cuprofix blue green B (dye D), and acid black ATT (dye E) was examined.Results show that QL exhibits the favorable flocculation performance and high stability.

  9. Evaluation of chitosan quaternary ammonium salt-modified resin denture base material.

    Science.gov (United States)

    Song, Rong; Zhong, Zhaohua; Lin, Lexun

    2016-04-01

    Chitosan quaternary ammonium salt displays good antioxidant and antibacterial characteristics and it shows appreciable solubility in water. When added to the traditional denture material to form a resin base, it could promote good oral health by improving the oral environment. In this study, chitosan quaternary ammonium salt was added to the denture material following two different methods. After three months of immersion in artificial saliva, the specimens were tested for tensile strength and were scanned by electron microscope. The murine fibroblast cytotoxicity and antibacterial properties were also tested. The result showed no significant differences in the tensile strength and in the proliferation of murine L929 fibroblast cells. The two structures of chitosan quaternary ammonium salt-modified denture material had different degrees of corrosion resistance and antimicrobial properties. These results indicate that chitosan quaternary ammonium salt-modified resin denture base material has the potential to become a new generation oral denture composite material.

  10. Effect of quaternary ammonium salts on flotation behavior of aluminosilicate minerals

    Institute of Scientific and Technical Information of China (English)

    ZHAO Sheng-gui; ZHONG Hong; LIU Guang-yi

    2007-01-01

    The electrokinetic properties and flotation of diaspore, kaolinite, pyrophyllite and illite with quaternary ammonium salts collectors were studied. The results of flotation tests show that the collecting ability of quaternary ammonium salts for the four minerals is in the order(from strong to weak) of octadecyl dimethyl benzyl ammonium chloride(ODBA), cetyl trimethyl ammonium bromide(CTAB), dodecyl trimethyl ammonium chloride(DTAC). Under the condition of alkalescence, it is possible to separate the diaspore from the silicate minerals such as kaolinite, illite and pyrophyllite using quaternary ammonium salts as collector. Isoelectric points (IEP) of diaspore, kaolinite, pyrophyllite and illite are pH=6.0, 3.4, 2.3 and 3.2, respectively. Quaternary ammonium salts can change ζ-potential of the aluminosilicate minerals obviously. The flotation mechanisms were explained by ζ-potential and Fourier transform infrared spectrum (FT-IR) measurements. The results demonstrate that only electrostatic interaction takes place between aluminosilicate minerals (diaspore, kaolinite, pyrophyllite and illite) and quaternary ammonium salts.

  11. Quaternary ammonium salt derivatives of allylphenols with peripheral analgesic effect

    Directory of Open Access Journals (Sweden)

    A. B de Oliveira

    1991-01-01

    Full Text Available Ammonium salt derivatives of natural allylphenols were synthesized with the purpose of obtaining potential peripheral analgesics. These drugs, by virtue of their physicochemical properties, would not be able to cross the blood brain barrier. Their inability to enter into the central nervous system (CNS should prevent several adverse effects observed with classical opiate analgesics (Ferreira et al., 1984. Eugenol (1 O-methyleugenol (5 and safrole (9 were submitted to nitration, reduction and permethylation, leading to the ammonium salts 4, 8 and 12. Another strategy applied to eugenol (1, consisting in its conversion to a glycidic ether (13, opening the epoxide ring with secondary amines and methylation, led to the ammonium salts 16 and 17. All these ammonium salts showed significant peripheral analgesic action, in modified version of the Randall-Sellito test (Ferreira et al. 1978, at non-lethal doses. The ammonium salt 8 showed an activity comparable to that of methylnalorphinium, the prototype of an ideal peripheral analgesic (Ferreira et al., 1984.

  12. Synthesis and Spectroscopic Characterisation of N-Alkyl Quaternary Ammonium Salts Typical Precursors of Cyanines

    OpenAIRE

    Almeida, P; Reis, L. V.; SANTOS, P.F.; Ramos, S. S.; Pardal, A. C.

    2002-01-01

    The synthesis and spectroscopic characterisation of some representative N-alkylsubstituted quaternary ammonium salts derived from benzothiazole, benzoxazole, benzoselenazole, indole and quinoline are described. These heterocyclic salts, bearing an activated methyl group in the 2-position in relation to the nitrogen atom and N-methyl, -pentyl, -hexyl and -decyl chains, are typical precursors of cyanine dyes.

  13. Synthesis and Spectroscopic Characterisation of N-Alkyl Quaternary Ammonium Salts Typical Precursors of Cyanines

    Directory of Open Access Journals (Sweden)

    P. Almeida

    2002-03-01

    Full Text Available The synthesis and spectroscopic characterisation of some representative N-alkylsubstituted quaternary ammonium salts derived from benzothiazole, benzoxazole, benzoselenazole, indole and quinoline are described. These heterocyclic salts, bearing an activated methyl group in the 2-position in relation to the nitrogen atom and N-methyl, -pentyl, -hexyl and -decyl chains, are typical precursors of cyanine dyes.

  14. Superoxide Anion Radical Scavenging Ability of Quaternary Ammonium Salt of Chitosan

    Institute of Scientific and Technical Information of China (English)

    Xiao Yan ZHU; Jian Min WU; Zhi Shen JIA

    2004-01-01

    A series of N-alkyl or N-aryl chitosan quaternary ammonium salt were prepared using 96% deacetylated chitosan. Their scavenging activities against superoxide anion radical were investigated by chemiluminescence. The IC50 values of these compounds range from 280 to 880 μg/mL, which should be attributed to their different substitutes.

  15. 40 CFR 721.9075 - Quaternary ammonium salt of fluorinated alkylaryl amide.

    Science.gov (United States)

    2010-07-01

    ... fluorinated alkylaryl amide. 721.9075 Section 721.9075 Protection of Environment ENVIRONMENTAL PROTECTION... amide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as quaternary ammonium salt of fluorinated alkylaryl amide (PMN No. P-92-688)...

  16. Synthesis and biological activity of quaternary ammonium salt-type agents containing cholesterol and terpenes.

    Science.gov (United States)

    Novotná, Eva; Waisser, Karel; Kuneš, Jiří; Palát, Karel; Buchta, Vladimír; Stolaříková, Jiřina; Beckert, Rainer; Wsól, Vladimír

    2014-06-01

    New quaternary ammonium salt-type compounds with lipophilic cholesterol and terpene moieties were synthesized. The compounds showed promising antibacterial and antimycobacterial activities. Those compounds containing the cholesterol moiety showed significant activity against Staphylococcus aureus, Staphylococcus epidermidis, and Enterococcus faecium. On the contrary, the antimycobacterial activity increased with the presence of the terpene unit in the molecule.

  17. Polyamide 6 Nanocomposites with Inorganic Particles Modified with Three Quaternary Ammonium Salts

    Directory of Open Access Journals (Sweden)

    Hélio de Lucena Lira

    2011-11-01

    Full Text Available The purpose of this study was to obtain polyamide 6 nanocomposites with national organically modified clay with three quaternary ammonium salts. The obtained results confirm the intercalation of molecules of salt in the clay layers, and a good interaction with the polymer, showing the formation of intercalated and/or partially exfoliated structures. The nanocomposites showed similar thermal stability compared to pure polymer, and the mechanical properties presented interesting and promising results.

  18. Mechanisms of flotation separation of diaspore and kaolinite by quaternary ammonium salt DTAL

    Institute of Scientific and Technical Information of China (English)

    陈湘清; 胡岳华; 王毓华

    2004-01-01

    The FTIR spectroscopy indicates that the adsorption of quaternary ammonium salt DTAL on the diaspore and kaolinite is physical adsorption. The adsorption of cationic surfactants measured by two-phase titration shows that the adsorption on the kaolinite is notably more than that on diaspore. The adsorption isotherm on kaolinte is linear while that of DTAL on diaspore is two-step flat form. The analysis on the cationic ions of kaolinite supernatants shows that kaolinite releases plenty of crystalloid structure ions which countervail the crystalloid charge because of the adsorption of the cationic surfactant. The mechanisms of the quaternary ammonium salt DTAL on flotation separation of diaspore and kaolinite include ion exchange interaction as well as electrostatic force.

  19. SN2-type ring opening of substituted--tosylaziridines with zinc (II) halides: Control of racemization by quaternary ammonium salt

    Indian Academy of Sciences (India)

    Manas K Ghorai; Deo Prakash Tiwari; Amit Kumar; Kalpataru Das

    2011-11-01

    Quaternary ammonium salt mediated highly regioselective ring opening of aziridines with zinc(II) halides to racemic and non-racemic -halo amines in excellent yield and selectivity is described. The reaction proceeds via an SN2-type pathway and the partial racemization of the starting substrate and the product was effectively controlled by using quaternary ammonium salts to afford the enantioenriched products (er up to 95:5).

  20. Effect of quaternary ammonium salts in the process of extracting oil filled rubber from latex

    Directory of Open Access Journals (Sweden)

    N. S. Nikulina

    2016-01-01

    Full Text Available Currently, much attention is paid to the improvement of production technology of synthetic rubber. Much attention is given to rubber is produced by emulsion polymerization. This is due to the fact that rubbers produced by emulsion polymerization have a number of positive characteristics, and are widely used in the tire and rubber industry, in composite formulations for various purposes. In recent years, the technology of production of synthetic rubbers are widely used quaternary ammonium salts which are produced on an industrial scale. Application low and high molecular weight quaternary ammonium salts to reduce pollution of environ-mental protection, exclude the use of mineral salts without significant changes in the process flowsheet. It is found that quaternary ammonium salts react with the components of the emulsion system to form insoluble complexes, which are captured produced rubber crumb. However, Applications, quaternary salts in the manufacture of oil-filled rubber in the literature sources have not been given due attention. The study presents the results of research on the effect of the concentration of a coagulating agent, tempera tours and concentration of the dispersed phase in the process of coagulation of latex in the preparation of oil-filled rubber stamps SCS-30 ARKM-15. The concentration of the coagulating agent does not significantly affect the process of separation of the rubber from the latex. The process of isolation rubber latex is advantageously carried out at a reduced temperature. The concentration of the dispersed phase also provides material effect on the coagulation process. The lead researches mouthestablished that produced rubber, rubber compounds and vulcanizates based on these indicators correspond to their requirements.

  1. Flotation and adsorption of quaternary ammonium salts collectors on kaolinite of different particle size

    Institute of Scientific and Technical Information of China (English)

    Jiang Hao; Liu Guorong; Hu Yuehua; Xu Longhua; Yu Yawen; Xie Zhen; Chen Haochuan

    2013-01-01

    The flotation behaviors of decyltrimethylammonium (103C),dodecyltrimethylammonium chloride (DTAC),tetradecyltrimethylammonium chloride (TTAC) and cetyltrimethylammonium chloride (CTAC) on kaolinite of different particle size fraction were studied.The adsorbed amount and adsorption isotherms of collectors on kaolinite were determined for painstaking investigation into the adsorption of quaternary amines at kaolinite-water interface by ultraviolet spectrophotometer methods.The flotation results show that the flotation recovery of kaolinite of different particle fraction increases with an increase in pH when 103C,DTAC,TrAC and CTAC are used as collectors.As the concentration of collectors increases,the flotation recovery increases.Particle size of kaolinite has a strong effect on flotation.The flotation recovery of fine kaolinite decreases with the carbon chain of quaternary ammonium salts collectors increasing,while coarse kaolinite is on the contrary.The adsorbed amount tests and adsorption isotherms show that adsorbed amount increases when the particle size of kaolinite increases or when the carbon chain length of quaternary ammonium salts increases.Within the range of flotation collector concentration,the longer the hydrocarbon chain,the more probable to be absolutely adsorbed by fine kaolinite particles and then the lower the collector concentration in the bulk,which leds to lower flotation recovery.

  2. Bio-based ionic liquid crystalline quaternary ammonium salts: properties and applications.

    Science.gov (United States)

    Sasi, Renjith; Rao, Talasila P; Devaki, Sudha J

    2014-03-26

    In the present work, we describe the preparation, properties, and applications of novel ionic liquid crystalline quaternary ammonium salts (QSs) of 3-pentadecylphenol, a bio-based low-cost material derived from cashew nut shell liquid. Amphotropic liquid crystalline phase formation in QSs was characterized using a combination of techniques, such as DSC, PLM, XRD, SEM, and rheology, which revealed the formation of one, two, and three dimensionally ordered mesophases in different length scales. On the basis of these results, a plausible mechanism for the formation of specific modes of packing in various mesophases was proposed. Observation of anisotropic ionic conductivity and electrochemical stability suggests their application as a solid electrolyte.

  3. Dimethyl carbonate synthesis via transesterification catalyzed by quaternary ammonium salt functionalized chitosan

    Institute of Scientific and Technical Information of China (English)

    Yuan Zhao; Liang Nian He; Yuan Yi Zhuang; Jin Quan Wang

    2008-01-01

    A quaternary ammonium salt covalently linked to chitosan was first used as a catalyst for dimethyl carbonate (DMC) synthesis by the transesterification of propylene carbonate (PC) with methanol. The effects of various reaction variables like reaction time, temperature and pressure on the catalytic performance were also investigated. 54% DMC yield and 71% PC conversion were obtained under the optimal reaction conditions. Notably, the catalyst was able to be reused with retention of high catalytic activity and selectivity. Consequently, the process presented here has great potential for industrial application due to its advantages such as stability, easy preparation from renewable biopolymer, and simple separation from products.

  4. Quaternary ammonium salt N-(dodecyloxycarboxymethyl)-N,N,N-trimethyl ammonium chloride induced alterations in Saccharomyces cerevisiae physiology

    Indian Academy of Sciences (India)

    EWA OBŁĄK; AGATA PIECUCH; EWA MACIASZCZYK-DZIUBIŃSKA; DONATA WAWRZYCKA

    2016-12-01

    We investigated the influence of the quaternary ammonium salt (QAS) called IM (N-(dodecyloxycarboxymethyl)-N,N,N-trimethyl ammonium chloride) on yeast cells of the parental strain and the IM-resistant mutant (EO25 IMR)growth. The phenotype of this mutant was pleiotropic. The IMR mutant exhibited resistance to ethanol, osmotic shockand oxidative stress, as well as increased sensitivity to UV. Moreover, it was noted that mutant EO25 appears to havean increased resistance to clotrimazole, ketoconazole, fluconazole, nystatin and cycloheximide. It also toleratedgrowth in the presence of crystal violet, DTT and metals (selenium, tin, arsenic). It was shown that the presence ofIM decreased ergosterol level in mutant plasma membrane and increased its unsaturation. These results indicatechanges in the cell lipid composition. Western blot analysis showed the induction of Pma1 level by IM. RT-PCRrevealed an increased PMA1 expression after IM treatment.

  5. Polydimethylsiloxane-polymethacrylate block copolymers tethering quaternary ammonium salt groups for antimicrobial coating

    Science.gov (United States)

    Qin, Xiaoshuai; Li, Yancai; Zhou, Fang; Ren, Lixia; Zhao, Yunhui; Yuan, Xiaoyan

    2015-02-01

    Block copolymers PDMS-b-PDMAEMA were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization involving N,N-dimethylaminoethyl methacrylate (DMAEMA) by using poly(dimethylsiloxane) (PDMS) macro-chain transfer agent. And, the tertiary amino groups in PDMAEMA were quaternized with n-octyliodide to provide quaternary ammonium salts (QPDMAEMA). The well-defined copolymers generated composition variation and morphology evolvement on film surfaces, which were characterized by X-ray photoelectron spectroscopy, atomic force microscopy, and contact angle measurements. The results indicated that the enrichment of QPDMAEMA brought about lower elemental ratios of Si/N on the film surfaces. The surface morphologies evolved with the variations of QPDMAEMA content, and the variation trend of film roughness was exactly opposite to that of water contact angle hysteresis. With regard to structure-antimicrobial relationships, the copolymer films had more evident antimicrobial activity against Gram-positive, Bacillus subtilis, and the surfaces with heterogeneous morphology and higher N+ content presented better antimicrobial activity. The functionalized copolymers based PDMS and quaternary ammonium salts materials have the potential applications as antimicrobial coatings.

  6. Polydimethylsiloxane-polymethacrylate block copolymers tethering quaternary ammonium salt groups for antimicrobial coating

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Xiaoshuai; Li, Yancai; Zhou, Fang; Ren, Lixia; Zhao, Yunhui, E-mail: zhaoyunhui@tju.edu.cn; Yuan, Xiaoyan

    2015-02-15

    Highlights: • A series of PDMS-b-QPDMAEMA block copolymers were synthesized via RAFT polymerization. • The composition and morphology of the copolymer films strongly depended on the content of QPDMAEMA. • Migration of QPDMAEMA blocks toward surface was promoted when contacting with water. • Heterogeneous film surfaces with higher N{sup +} content exhibited more obvious antimicrobial activity. - Abstract: Block copolymers PDMS-b-PDMAEMA were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization involving N,N-dimethylaminoethyl methacrylate (DMAEMA) by using poly(dimethylsiloxane) (PDMS) macro-chain transfer agent. And, the tertiary amino groups in PDMAEMA were quaternized with n-octyliodide to provide quaternary ammonium salts (QPDMAEMA). The well-defined copolymers generated composition variation and morphology evolvement on film surfaces, which were characterized by X-ray photoelectron spectroscopy, atomic force microscopy, and contact angle measurements. The results indicated that the enrichment of QPDMAEMA brought about lower elemental ratios of Si/N on the film surfaces. The surface morphologies evolved with the variations of QPDMAEMA content, and the variation trend of film roughness was exactly opposite to that of water contact angle hysteresis. With regard to structure-antimicrobial relationships, the copolymer films had more evident antimicrobial activity against Gram-positive, Bacillus subtilis, and the surfaces with heterogeneous morphology and higher N{sup +} content presented better antimicrobial activity. The functionalized copolymers based PDMS and quaternary ammonium salts materials have the potential applications as antimicrobial coatings.

  7. Tetramethylammonium tetrafluoroborate: The smallest quaternary ammonium tetrafluoroborate salt for use in electrochemical double layer capacitors

    Science.gov (United States)

    Park, Sieun; Kim, Ketack

    2017-01-01

    Tetramethylammonium (TMA) ion is the smallest quaternary ammonium ion (QAI) that can be used in electrochemical double layer capacitor (EDLC) applications. Small ions improve the capacitance of EDLCs by increasing the adsorbed ionic density. Herein, we first report the utilization of TMA BF4 in EDLCs and the properties of the smallest QAI are investigated. However, because of the poor solubility of TMA BF4, it must be combined with another salt, forming a binary-salt electrolyte. In this study, the maximum TMA BF4 concentration used was 5 mol%. These binary salt mixtures contain a conventional electrolyte salt such as tetraethylammonium BF4, trimethylethylammonium BF4, or spiro-bipyrrolidinium BF4. In addition, 4-5 mol% TMA BF4 was added to the conventional salt solution and a binary-salt electrolyte was obtained, leading to 12-13% increase in the capacitance compared to that of a 100 mol% conventional electrolyte at 10 A g-1. This work proposes a new method to improve the performance of EDLCs by using binary-salt electrolytes.

  8. Green methodology for the recovery of Cr (VI from tannery effluent using newly synthesized quaternary ammonium salt

    Directory of Open Access Journals (Sweden)

    K.S. Yoganand

    2017-02-01

    Full Text Available Leather tanning industries release effluents into the river through various canals. These effluents contain chromium (VI contaminating the river and the ground water as well. To fix a solution for this issue a simple and selective solvent extraction method has been applied by using a newly synthesized quaternary ammonium salt viz 2-benzoylethylheptyldimethylammonium bromide. By varying the parameters such as quaternary ammonium salts, sulfuric acid, pH, solvents, equilibration time and aqueous organic ratio the extraction efficiency has been determined.

  9. Porous polymers bearing functional quaternary ammonium salts as efficient solid catalysts for the fixation of CO2 into cyclic carbonates

    Science.gov (United States)

    Cai, Sheng; Zhu, Dongliang; Zou, Yan; Zhao, Jing

    2016-07-01

    A series of porous polymers bearing functional quaternary ammonium salts were solvothermally synthesized through the free radical copolymerization of divinylbenzene (DVB) and functionalized quaternary ammonium salts. The obtained polymers feature highly cross-linked matrices, large surface areas, and abundant halogen anions. These polymers were evaluated as heterogeneous catalysts for the synthesis of cyclic carbonates from epoxides and CO2 in the absence of co-catalysts and solvents. The results revealed that the synergistic effect between the functional hydroxyl groups and the halide anion Br- afforded excellent catalytic activity to cyclic carbonates. In addition, the catalyst can be easily recovered and reused for at least five cycles without significant loss in activity.

  10. Formation and shape-control of hierarchical cobalt nanostructures using quaternary ammonium salts in aqueous media

    Science.gov (United States)

    Deshmukh, Ruchi; Mehra, Anurag

    2017-01-01

    Aggregation and self-assembly are influenced by molecular interactions. With precise control of molecular interactions, in this study, a wide range of nanostructures ranging from zero-dimensional nanospheres to hierarchical nanoplates and spindles have been successfully synthesized at ambient temperature in aqueous solution. The nanostructures reported here are formed by aggregation of spherical seed particles (monomers) in presence of quaternary ammonium salts. Hydroxide ions and a magnetic moment of the monomers are essential to induce shape anisotropy in the nanostructures. The cobalt nanoplates are studied in detail, and a growth mechanism based on collision, aggregation, and crystal consolidation is proposed based on a electron microscopy studies. The growth mechanism is generalized for rods, spindles, and nearly spherical nanostructures, obtained by varying the cation group in the quaternary ammonium hydroxides. Electron diffraction shows different predominant lattice planes on the edge and on the surface of a nanoplate. The study explains, hereto unaddressed, the temporal evolution of complex magnetic nanostructures. These ferromagnetic nanostructures represent an interesting combination of shape anisotropy and magnetic characteristics.

  11. Properties of new low melting point quaternary ammonium salts with bis(trifluoromethanesulfonyl)imide anion

    Science.gov (United States)

    Kärnä, Minna; Lahtinen, Manu; Kujala, Anna; Hakkarainen, Pirkko-Leena; Valkonen, Jussi

    2010-11-01

    Eight new monocationic quaternary ammonium (QA) salts with the bis(trifluoromethanesulfonyl)imide (TFSI) anion were prepared by metathesis using our previously reported QA halides as precursors. New salts were characterized both in liquid and solid state using 1H and 13C NMR techniques, mass spectroscopy and elemental analysis together with X-ray diffraction and thermoanalytical methods. In addition, residual water content, viscosity and conductivity measurements were made for three of the room-temperature ionic liquids (RTILs). The crystal structures of three compounds were determined by X-ray single crystal diffraction. Powder diffraction was used to study the crystallinity of the solid salts and to compare structural similarities between the single crystals and the microcrystalline bulk powders. Three of the salts are liquid below room temperature, having broad liquid ranges (˜300 °C), and in total five out of eight salts melt below 100 °C. Moreover, powder diffraction data of the two RTILs were able to be measured at sub-ambient temperatures using in situ low-temperature powder X-ray diffraction revealing high crystallinity on both RTILs below their freezing point. The RTILs presented relatively high conductivities (˜0.1-0.2 S m -1) and moderate to relatively low viscosities. The determined physicochemical properties of the reported ILs suggest their applicability on various applications such as heat transfer fluids, high temperature synthesis and lubricants.

  12. Biotreatment on cellulose fluff pulp: quaternary ammonium salts finish and grafting with beta-cyclodextrin.

    Science.gov (United States)

    Ghemati, Djamila; Oudia, Atika; Aliouche, Djamel; Lamouri, Saad

    2009-11-01

    For its potential performances to be expanded, cellulose needs to be processed in different ways. Therefore, an object of the present work was to provide a chemical modification of cellulose through: a specific finish with two quaternary ammonium salts (namely Aliquat 336 and Aliquat 1529, respectively). Chemical grafting of beta-cyclodextrin derivative (beta-CD) onto fibers followed by the inclusion of benzoic acid in the grafted CD cavities as a probe chemical. Physicochemical properties and performances of the untreated and treated fibers have been determined with infrared spectra, microscopy, swelling measurements, antimicrobial finishing tests, and dye adsorption. Our results show that cellulose fibers can be efficiently modified with no significant changes in its structural and surface properties; the treated fibers show an attractive behavior in swelling, dye adsorption and antibacterial activity.

  13. Organometallics and quaternary ammonium salts affect calcium ion desorption from lecithin liposome membranes

    Energy Technology Data Exchange (ETDEWEB)

    Kral, T.E.; Kuczera, J.; Przestalski, S. [Dept. of Physics and Biophysics, Agricultural Univ., Wroclaw (Poland)

    2001-06-01

    The objective of the present work was to compare the effects of groups of tin and lead organometallic compounds and their mixtures with amphiphilic quaternary ammonium salts (QAS) on the process of calcium ion desorption from lecithin liposome membranes, as dependent on the properties of the hydrophilic and hydrophobic parts of QAS. In the investigations the method of radioactive labels was applied. Synergism and antagonism in the action of both groups of compounds were found. The effectiveness of the cooperation depended more on chain length of QAS compounds than on the size and polarity of their hydrophobic parts. The most effective of all compounds studied was a the mixture of benzyldimethylammonium chloride in a mixture with tripropyltin. Since the rate of calcium desorption proved to be a good measure of efficacy of biologically active surfactants, it seems that the conclusions reached in this paper may be useful for choosing compounds which are able to decontaminate the environment polluted with heavy metals. (orig.)

  14. Influence of alkyl group of imidazolinyl-quaternary-ammonium-salt on corrosion inhibition efficiency

    Institute of Scientific and Technical Information of China (English)

    SHI Shun-cun; WANG Xue-ye; YI Ping-gui; CAO Chen-zhong; DENG Tong-tong; SU Jie-shu

    2006-01-01

    The action between imidazolinyl-quaternary-ammonium-salt(IQAS) molecule and Fe atom was studied,and the influence of the alkyl group connected with N atom of imidazoline ring on corrosion inhibition efficiency was explored. Quantum chemical methods, HF/6- 31 G and HF/Lan L2 dz, were applied successively to calculate the parameters such as front molecular orbit energy of IQAS Ⅰ-Ⅳ and chemical adsorption for IQAS Ⅰ-Ⅳ and Fe atom.The corrosion inhibition efficiency was measured with the weight loss method of carbon steel samples in acidic solution and oil field sewage. Based on the theoretical analyses and experimental results, it is concluded that N-Fe coordination bond is formed between IQAS molecule and Fe atom, corrosion inhibition efficiency is decreased in the following order(from large to small): IQAS Ⅳ, IQAS Ⅲ, IQAS Ⅱ , IQAS Ⅰ.

  15. Organometallics and quaternary ammonium salts affect calcium ion desorption from lecithin liposome membranes.

    Science.gov (United States)

    Kral, T E; Kuczera, J; Przestalski, S

    2001-01-01

    The objective of the present work was to compare the effects of groups of tin and lead organometallic compounds and their mixtures with amphiphilic quaternary ammonium salts (QAS) on the process of calcium ion desorption from lecithin liposome membranes, as dependent on the properties of the hydrophilic and hydrophobic parts of QAS. In the investigations the method of radioactive labels was applied. Synergism and antagonism in the action of both groups of compounds were found. The effectiveness of the cooperation depended more on chain length of QAS compounds than on the size and polarity of their hydrophobic parts. The most effective of all compounds studied was a the mixture of benzyldimethylammonium chloride in a mixture with tripropyltin. Since the rate of calcium desorption proved to be a good measure of efficacy of biologically active surfactants, it seems that the conclusions reached in this paper may be useful for choosing compounds which are able to decontaminate the environment polluted with heavy metals.

  16. Quaternary ammonium salts with tetrafluoroborate anion: Phytotoxicity and oxidative stress in terrestrial plants

    Energy Technology Data Exchange (ETDEWEB)

    Biczak, Robert, E-mail: r.biczak@ajd.czest.pl

    2016-03-05

    Highlights: • The level of oxidative stress in mono- and dicotyledonous plants was comparable. • Chlorophyll content in the plants was correlated with QAS concentration in the soil. • POD activity increased in plants cultivated in soil with high QAS content. - Abstract: This paper discusses the impact of four quaternary ammonium salts (QAS) such as tetraethylammonium tetrafluoroborate [TEA][BF{sub 4}], tetrabutylammonium tetrafluoroborate [TBA][BF{sub 4}], tetrahexylammonium tetrafluoroborate [THA][BF{sub 4}], and tetraoctylammonium tetrafluoroborate [TOA][BF{sub 4}] on the growth and development of spring barley and common radish. Analogous tests were performed with the inorganic salt ammonium tetrafluoroborate [A][BF{sub 4}] for comparison purposes. Results indicated that the phytotoxicity of the QAS applied is dependent on the concentration of the substance and their number of carbon atoms. The most toxic compound was [TBA][BF{sub 4}], causing the greatest drop in fresh weight of both study plants, similar to the phytotoxic effects of [A][BF{sub 4}]. All the tested compounds caused oxidative stress in spring barley and common radish seedlings due to a drop in the chlorophyll content. Stress was also observed in plants, which was indicated by the increased level of ROS (reactive oxygen species) such as H{sub 2}O{sub 2} and lipid peroxidation of MDA (malondialdehyde). Due to the stress, both plants displayed changes in the activity of antioxidative enzymes such as superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD). Based on the results of the study, it was concluded that changes in chlorophyll levels and peroxidase activity are the best biomarkers to determine oxidative stress in plants.

  17. Investigation of melamine derived quaternary as ammonium salt potential shale inhibitor

    Science.gov (United States)

    Yu, Hongjiang; Hu, Weimin; Guo, Gang; Huang, Lei; Li, Lili; Gu, Xuefan; Zhang, Zhifang; Zhang, Jie; Chen, Gang

    2017-06-01

    Melamine, sodium chloroacetate and sodium hydroxide were used as raw materials to synthesize a kind of neutral quaternary ammonium salt (NQAS) as potential clay swelling inhibitor and water-based drilling fluid additive, and the reaction conditions were screened based on the linear expansion rate of bentonite. The inhibitive properties of NQASs were investigated by various methods, including montmorillonite (MMT) linear expansion test, mud ball immersing test, particle distribution measurement, thermogravimetric analysis and scanning electron microscopy etc. The results indicate that NQAS can inhibit expansion and dispersion of clay in water effectively. At the same condition, the bentonite linear expansion rate in NQAS-6 solution is much lower than those of others, and the hydration expansion degree of the mud ball in 0.5% NQAS-6 solution is appreciably weaker than the control test. The compatibility test indicates NQAS-6 could be compatible with the conventional additives in water-based drilling fluids, and the temperature resistance of modified starch was improved effectively. Meanwhile, the inhibitive mechanism was discussed through the particle distribution measurement.

  18. CO2 capture from simulated fuel gas mixtures using semiclathrate hydrates formed by quaternary ammonium salts.

    Science.gov (United States)

    Park, Sungwon; Lee, Seungmin; Lee, Youngjun; Seo, Yongwon

    2013-07-02

    In order to investigate the feasibility of semiclathrate hydrate-based precombustion CO2 capture, thermodynamic, kinetic, and spectroscopic studies were undertaken on the semiclathrate hydrates formed from a fuel gas mixture of H2 (60%) + CO2 (40%) in the presence of quaternary ammonium salts (QASs) such as tetra-n-butylammonium bromide (TBAB) and fluoride (TBAF). The inclusion of QASs demonstrated significantly stabilized hydrate dissociation conditions. This effect was greater for TBAF than TBAB. However, due to the presence of dodecahedral cages that are partially filled with water molecules, TBAF showed a relatively lower gas uptake than TBAB. From the stability condition measurements and compositional analyses, it was found that with only one step of semiclathrate hydrate formation with the fuel gas mixture from the IGCC plants, 95% CO2 can be enriched in the semiclathrate hydrate phase at room temperature. The enclathration of both CO2 and H2 in the cages of the QAS semiclathrate hydrates and the structural transition that results from the inclusion of QASs were confirmed through Raman and (1)H NMR measurements. The experimental results obtained in this study provide the physicochemical background required for understanding selective partitioning and distributions of guest gases in the QAS semiclathrate hydrates and for investigating the feasibility of a semiclathrate hydrate-based precombustion CO2 capture process.

  19. Modification of a Brazilian smectite clay with different quaternary ammonium salts

    Directory of Open Access Journals (Sweden)

    Maria Flávia Delbem

    2010-01-01

    Full Text Available In this work, a smectite clay from the State of Paraiba, Brazil, was treated with six different types of ammonium salts, which is an usual method to enhance the affinity between the clay and polymer for the preparation of nanocomposites. The clays, before and after modification, were characterized by X ray diffraction. The conformation of the salts within the platelets of the clay depended on the number of long alkyl chains of the salt. The thermal stability of the clays was also studied. The ammonium salts thermal decomposition was explained in light of their position within the organoclays.

  20. Synthesis and Spectroscopic Characterisation of 2,3-Epoxy/3-Chloro-2-hydroxy Propyl Derivatives of Quaternary Ammonium Salts: Useful Cationic Fixing Agents

    Institute of Scientific and Technical Information of China (English)

    SHARIF Saima; AHMAD Saeed; IZHAR-UL-HAQ Mian Muhammad

    2008-01-01

    Eight mono-reactive and four bis-reactive 2,3-epoxy/3-chloro-2-hydroxy propyl derivatives of quaternary ammonium salts have been synthesised by reacting epichlorohydrin with suitable tertiary amines and diamines.Mono-reactive derivatives also contain cyano and carboxylic groups in addition to 2,3-epoxy/3-chloro-2-hydroxy propyl groups. The structures of these quaternary ammonium salts have been characterised using IR and 1H NMR spectroscopic techniques. These quaternary ammonium chlorides have been applied to the cotton fabrics as pretreatments and aftertreatments and promising results have been obtained.

  1. Incorporation of quaternary ammonium salts containing different counterions to improve the performance of inverted perovskite solar cells

    Science.gov (United States)

    Yan, Po-Ruei; Huang, Wei-Jie; Yang, Sheng-Hsiung

    2017-02-01

    In this research, three quaternary ammonium salts containing different counterions, including tetrabutylammonium bromide (TBABr), tetrabutylammonium tetrafluoroborate (TBABF4), and tetrabutylammonium hexafluorophosphate (TBAPF6), were incorporated into [6,6]-phenyl-C61 butyric acid methyl ester (PCBM) as electron transporting layer (ETL). These salts-doped PCBM films revealed higher electron mobility and Fermi levels compared with the un-doped one. Better charge transfer at the interface between perovskite and salts-doped PCBM was also obtained from PL quenching experiments. Inverted perovskite solar cells with the configuration of ITO/PEDOT:PSS/CH3NH3PbI3/PCBM + salts/Ag were fabricated, and the JSC and FF of devices were significantly enhanced using salts-doped PCBM as ETL. The best device based on TBABF4-doped PCBM delivered a power conversion efficiency (PCE) up to 13.41%, which was superior to the one with undoped PCBM layer (PCE = 8.77%).

  2. Fluorosilicone multi-block copolymers tethering quaternary ammonium salt groups for antimicrobial purpose

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Fang; Qin, Xiaoshuai; Li, Yancai; Ren, Lixia; Zhao, Yunhui, E-mail: zhaoyunhui@tju.edu.cn; Yuan, Xiaoyan

    2015-08-30

    Highlights: • QAS-containing fluorosilicone multi-block copolymers were synthesized. • The block length of PHFBMA in the copolymers was tailored via RAFT polymerization. • Surface roughness of the copolymers decreased with the increased PHFBMA content. • A certain length of PHFBMA block enhanced C−N{sup +} percentage on the surface. - Abstract: Symmetrically structured fluorosilicone multi-block copolymers containing poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) and poly(hexafluorobutyl methacrylate) (PHFBMA) were sequentially synthesized via reversible addition–fragmentation chain transfer polymerization, using a polydimethylsiloxane (PDMS) chain transfer agent with dithiocarbonate groups at both ends. Then, the CBABC-type block copolymers were quaternized with n-octyliodide to tether quaternary ammonium salt (QAS) groups in the PDMAEMA blocks for the antimicrobial use. The obtained fluorosilicone copolymers showed clear variations in the C-N{sup +} composition and surface morphology on their films depending on the content of the PHFBMA blocks, which were characterized by X-ray photoelectron spectroscopy and atomic force microscopy, respectively. The results indicated that the symmetrical CBABC structure favored PDMS and QAS tethered blocks migrating to the film surface. With the mass percentage of the PHFBMA increased from 0 to 32.5%, the surface roughness of the copolymer film decreased gradually with a tendency to form a smooth surface. Owing to the surface properties, fluorosilicone multi-block copolymers containing a certain amount of PHFBMA with higher C-N{sup +} content and relatively smooth morphology demonstrated obvious antimicrobial activity against Gram-positive bacteria, Bacillus subtilis and Gram-negative bacteria, Escherichia coli. The functionalized multi-block copolymers based on fluorosilicone and QAS groups would have potential applications in antimicrobial coatings.

  3. Substituted Quaternary Ammonium Salts Improve Low-Temperature Performance of Double-Layer Capacitors

    Science.gov (United States)

    Brandon, Erik J.; Smart, Marshall C.; West, William C.

    2011-01-01

    Double-layer capacitors are unique energy storage devices, capable of supporting large current pulses as well as a very high number of charging and discharging cycles. The performance of doublelayer capacitors is highly dependent on the nature of the electrolyte system used. Many applications, including for electric and fuel cell vehicles, back-up diesel generators, wind generator pitch control back-up power systems, environmental and structural distributed sensors, and spacecraft avionics, can potentially benefit from the use of double-layer capacitors with lower equivalent series resistances (ESRs) over wider temperature limits. Higher ESRs result in decreased power output, which is a particular problem at lower temperatures. Commercially available cells are typically rated for operation down to only 40 C. Previous briefs [for example, Low Temperature Supercapacitors (NPO-44386), NASA Tech Briefs, Vol. 32, No. 7 (July 2008), p. 32, and Supercapacitor Electrolyte Solvents With Liquid Range Below 80 C (NPO-44855), NASA Tech Briefs, Vol. 34, No. 1 (January 2010), p. 44] discussed the use of electrolytes that employed low-melting-point co-solvents to depress the freezing point of traditional acetonitrile-based electrolytes. Using these modified electrolyte formulations can extend the low-temperature operational limit of double-layer capacitors beyond that of commercially available cells. This previous work has shown that although the measured capacitance is relatively insensitive to temperature, the ESR can rise rapidly at low temperatures, due to decreased electrolyte conductance within the pores of the high surface- area carbon electrodes. Most of these advanced electrolyte systems featured tetraethylammonium tetrafluoroborate (TEATFB) as the salt. More recent work at JPL indicates the use of the asymmetric quaternary ammonium salt triethylmethylammonium tetrafluoroborate (TEMATFB) or spiro-(l,l')-bipyrrolidium tetrafluoroborate (SBPBF4) in a 1:1 by volume solvent

  4. Humidity Sensitive Properties of a Coplymer of Quaternary Ammonium Salt with Polyether-salt Complex

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    1 Results Humidity sensors have been widely used in meteorology, process controlling, agriculture and manufacturing. In recent year, more attention has been paid to resistive-type polymeric humidity sensors. Polyelectrolytes are the most usually used materials for their advantages of high sensitivity, fast response, easy preparation, low cost, etc[1,2]. In this paper quaternized and salt-doped copolymer of 2-(dimethylamino) ethylmethacrylate (DMAEMA) with poly(ethylene glycol) methyl ether methacrylate ...

  5. The association effect of quaternary ammonium salt on carboxymethyl cellulose and its analytical applications.

    Science.gov (United States)

    Wang, Yanhua; Gao, Chanjuan; Yang, Shengke

    2015-01-01

    Sodium carboxymethyl cellulose (CMC) has been extensively used in petroleum, geology, common household chemicals, food, medicine and other industries, owing to its excellent water-soluble, emulsifying, water retention and film forming properties. It is known as 'industrial monosodium glutamate'. However, the research of the test method on CMC is far behind the research of its actual application value. This study showed that, weak acid or weak basic medium, the carboxyl groups dissociated from CMC, existing as a big negative ion, which can form ion-association complexes with some quaternary ammonium cations through electrostatic and hydrophobic interactions. The absorption spectrum changes and Triton-X100 can increase the sensitivity of the system. The maximum absorption wavelengths are, respectively, about 256 nm for dodecyl trimethyl ammonium bromide (LTAB), 244 nm for tetradecyltrimethyl ammonium bromide (TTAB) and 240 nm for cetyltrimethyl ammonium bromide (CTAB) with CMC. The reactions show very high sensitivities and the maximum molar absorption coefficients are 1.10 × 10(4) L/(mol·cm) for LTAB system, 1.24 × 10(6) L/(mol·cm) for TTAB system and 1.78 × 10(6) L/(mol·cm) for CTAB system. This method is simple and rapid, and can be applied for the spectrophotometric determination of trace CMC in the supernatant of centrifuged drilling mud.

  6. 聚硅氧烷季铵盐的合成及应用研究进展%Progress on Preparation and Application of Polysiloxane Quaternary Ammonium Salts

    Institute of Scientific and Technical Information of China (English)

    黄良仙; 肖波; 杨军胜; 安秋凤

    2013-01-01

    Four synthetic methods for preparations of polysiloxane quaternary ammonium salts were summarized , i. e. quaternization reaction of amino silane (amino silicone) with quaternary ammonium reagent, substituted reaction of halogen allcyl silane with tertiary amine, hydrosilylation and quaternization reaction of the hydrogen silicone oil with unsaturated compounds containing active group, and the equilibrium polymerization or condensation reaction of methyl silicone oil and quaternary ammonium salt. The application of the polysiloxane quaternary ammonium salts were introduced in the fabric finishing, daily chemical products, pesticides , sewage treatment and other applications. In the end, the development trends of polysiloxane quaternary ammonium salt were proposed.%阐述了聚硅氧烷季铵盐的4种合成方法:氨基硅烷(油)与季铵化试剂的季铵化反应法、卤烃基硅烷与叔胺的取代反应法、含氢硅油(烷)与含活性基团的不饱和化合物的硅氢加成及季铵化反应法、甲基硅油与氨基硅烷、季铵盐的平衡反应法,介绍了其在织物整理、日化产品、农药、污水处理等方面的应用,并对其发展前景进行了展望.

  7. [Synthesis of a nano-antibacterial inorganic filler containing a quaternary ammonium salt with long chain alkyl and its effect on dental resin composites].

    Science.gov (United States)

    Junling, Wu; Kaiyun, Zhou; Ting, Zhu; Chuanjian, Zhou

    2014-10-01

    This study aimed to synthesize a novel nano-antibacterial inorganic filler that contains a quaternary ammonium salt with long chain alkyl and to report the antibacterial property of dental resin composites. A novel nano-antibacterial inorganic filler that contains a quaternary ammonium salt with long chain alkyl was synthesized based on previous research. The antibacterial property of the filler was measured. The surface of the novel nano-antibacterial inorganic filler was modified by a coupling agent to achieve a good interfacial bonding between the filler and the resin matrix. Infrared spectrum analysis was carried out. The modified novel nano-antibacterial inorganic fillers were then incorporated into the dental resin matrix. The dispersion of the fillers was observed and compared with those incorporated into Tetric N-Ceram, a commercial resin composite, under a scanning electron microscope. Streptococcus mutans was used in testing the antibacterial property of the dental resin composites. A quaternary ammonium salt with a long chain alkyl was successfully grafted onto the surface of nano-silica particles. The novel nano-antibacterial inorganic filler that contains quaternary ammonium salt with a long chain alkyl showed stronger antibacterial efficacy than the antibacterial inorganic filler that contains quaternary ammonium salt with a short chain alkyl. The modified novel antibacterial inorganic fillers displayed a homogeneous dispersion in the resin composite bulk and combined closely with the resin matrix, similar to the Tetric N-Ceram. The resin composites that contain novel antibacterial inorganic fillers showed stronger antibacterial effect on Streptococcus mutans compared with the control group. The novel nano-antibacterial inorganic filler that contains a quaternary ammonium salt with long chain alkyl showed a strong antibacterial property. It also exhibited good compatibility with the dental resin matrix after undergoing coupling treatment.

  8. Perfluorinated quaternary ammonium salts of polyoxometalate anions: Fluorous biphasic oxidation catalysis with and without fluorous solvents

    Energy Technology Data Exchange (ETDEWEB)

    Maayan, Galia; Fish, Richard H.; Neumann, Ronny

    2003-05-28

    Perfluorinated quaternary ammonium cations, [CF{sub 3}(CF{sub 2}){sub 7}(CH{sub 2}){sub 3}]{sub 3}CH{sub 3}N{sup +} (RFN{sup +}), were synthesized and used as counter cations for the [WZnM{sub 2}(H{sub 2}O){sub 2}(ZnW{sub 9}O{sub 34}){sub 2}]{sup 12-} (M = Mn(II), Zn(II)), polyoxometalate. The (RFN{sup +}){sub 12}[WZnM{sub 2}(H{sub 2}O){sub 2}(ZnW9O{sub 34}){sub 2}] compounds were fluorous biphasic catalysts for alcohol and alkenol oxidation, and alkene epoxidation with aqueous hydrogen peroxide. Reaction protocols with or without a fluorous solvent were tested. The catalytic activity and selectivity was affected both by the hydrophobicity of the solvent and the substrate.

  9. Halogenated solvent interactions with N,N-dimethyltryptamine: formation of quaternary ammonium salts and their artificially induced rearrangements during analysis.

    Science.gov (United States)

    Brandt, Simon D; Martins, Cláudia P B; Freeman, Sally; Dempster, Nicola; Riby, Philip G; Gartz, Jochen; Alder, John F

    2008-07-04

    The psychoactive properties of N,N-dimethyltryptamine (DMT) 1a are known to induce altered states of consciousness in humans. This particular attribute attracts great interest from a variety of scientific and also clandestine communities. Our recent research has confirmed that DMT reacts with dichloromethane (DCM), either as a result of work-up or storage to give a quaternary N-chloromethyl ammonium salt 2a. Furthermore, this was observed to undergo rearrangement during analysis using gas chromatography-mass spectrometry (GC-MS) with products including 3-(2-chloroethyl)indole 3 and 2-methyltetrahydro-beta-carboline 4 (2-Me-THBC). This study further investigates this so far unexplored area of solvent interactions by the exposure of DMT to other halogenated solvents including dibromomethane and 1,2-dichloroethane (DCE). The N-bromomethyl- and N-chloroethyl quaternary ammonium derivatives were subsequently characterised by ion trap GC-MS in electron and chemical ionisation tandem MS mode and by NMR spectroscopy. The DCE-derived derivative formed at least six rearrangement products in the total ion chromatogram. Identification of mass spectrometry generated by-products was verified by conventional or microwave-accelerated synthesis. The use of deuterated DCM and deuterated DMT 1b provided insights into the mechanism of the rearrangements. The presence of potentially characteristic marker molecules may allow the identification of solvents used during the manufacture of controlled substances, which is often neglected since these are considered inert.

  10. Chromatographic retention behaviour, modelling and separation optimisation of the quaternary ammonium salt isometamidium chloride and related compounds on a range of reversed-phase liquid chromatographic stationary phases.

    Science.gov (United States)

    Schad, Gesa J; Euerby, Melvin R; Skellern, Graham G; Tettey, Justice N A

    2012-07-01

    This paper describes the reversed-phase liquid chromatographic behaviour of the trypanocidal quaternary ammonium salt isometamidium chloride and its related compounds on a range of liquid chromatographic phases possessing alkyl and phenyl ligands on the same inert silica. In a parallel study with various extended polar selectivity phases which possessed different hydrophobic/silanophilic (hydrogen bonding) activity ratios, the chromatographic retention/selectivities of the quaternary ammonium salts was shown to be due to a co-operative mechanism between hydrophobic and silanophilic interactions. The highly aromatic and planar isometamidium compounds were found to be substantially retained on stationary phases containing aromatic functionality via strong π-π interactions. The chemometric approach of principal component analysis was used to characterise the chromatographic behaviour of the isometamidium compounds on the differing phases and to help identify the dominant retention mechanism(s). Two-dimensional (temperature/gradient) retention modelling was employed to develop and optimise a rapid liquid chromatography method for the separation of the six quaternary ammonium salts within 2.5 min which would be suitable for bioanalysis using liquid chromatography-mass spectrometry. This is the first reported systematic study of the relationship between stationary phase chemistries and retention/selectivity for a group of quaternary ammonium salts.

  11. The physiological and morphological phenotype of a yeast mutant resistant to the quaternary ammonium salt N-(dodecyloxycarboxymethyl)-N,N,N-trimethyl ammonium chloride.

    Science.gov (United States)

    Obłak, Ewa; Gamian, Andrzej; Adamski, Ryszard; Ułaszewski, Stanisław

    2010-06-01

    We investigated the action of the quaternary ammonium salt (QAS) called IM (N-(dodecyloxycarboxymethyl)-N,N,N-trimethyl ammonium chloride) on Saccharomyces cerevisiae yeast cells. Changes in the yeast cell ultrastructure were confirmed by electron microscopy. We treated resistant mutant cells with QAS, and confirmed destruction of the mutant cytoplasm, an increase in the thickness of the cell wall, separation of the cell wall from the cytoplasm, and the accumulation of numerous lipid droplets. We also observed a relatively high production of lipids in the cells of the parental wild-type strain Sigma1278b and in its IM-resistant (IM(R)) mutant in the presence of the QAS. The IM(R) mutant showed increased sensitivity to CaCl(2) and SDS, and resistance to ethidium bromide, chloramphenicol, erythromycin and osmotic shock. It also tolerated growth at low pH. We suggest that the resistance to IM could be connected with the level of permeability of the cell membrane because the IM(R) mutant was sensitive to this compound in vivo in the presence of SDS and guanidine hydrochloride, which cause increased permeability of the cell plasma membrane.

  12. Studies on the Extraction of Gold(I) Cyanide by Quaternary Ammonium Salt Using 198Au as Tracer

    Institute of Scientific and Technical Information of China (English)

    ZHANGTianxi; CHENJing; 等

    2002-01-01

    The solvent extraction of KAu(CN)2 from alkaline solution by quaternary ammonium salts (trialkylmethylammonium chloride or cetyltrimethylammonium bromide) waw investigated by means of 198Au radioactive tracer method. Various parameters,such as the gold (I) concentration in aqueous phase,the modiffer,emulsifiation at the interface of two phases, and phase ratio used in the extraction of gold (I) were studied. The results demonstrate that almost all gold (I) in the aqueous phase was practically extracted into the organic phase. The water content in the organic phase decreased significantly with increase of gold (I) concentration using long chain alcohol as modifier,in contrast with the system with tributyl phosphate (TBP) as modifier. Emulsification at the interface of two phases decreases with an increase of modifier concentration in the organic phase or with the addition of a small amount of lysozyme into the aqueous phase. The method with 198Au tracer can be directly used to determine the Au(I) concentration both in aqueous and organic phases, which is especially suitable for the low concentration of Au(I).

  13. Quaternary ammonium salt containing soybean oil: an efficient nanosize gene delivery carrier for halophile green microalgal transformation.

    Science.gov (United States)

    Akbari, Fariba; Yari Khosroushahi, Ahmad; Yeganeh, Hamid

    2015-01-01

    Dunaliella salina, a halophile green microalga, is considered a robust photobioreactor and a remarkable cost beneficial system for the production of therapeutic recombinant proteins. In this study, with low overall cost, a proper cationic lipid was synthesized from renewable soybean oil as an efficient gene delivery carrier for D. salina cells to create appropriate protein-producing transformed cell lines. To obtain an effective carrier, quaternary ammonium salt containing soybean oil (QASSO) was synthesized through the ring opening reaction of the epoxy groups of epoxidized soybean oil with diethylamine. QASSO was characterized using nuclear magnetic resonance and Fourier-transform infrared instruments. QASSO was used to prepare nanolipoplex construct using plasmid DNA molecules containing green fluorescent protein (GFP) as reporter gene. These nanolipoplexes (QASSO-pGFP, N/P=3) and QASSO had diameter of 63.62 and 110.63 nm, and zeta potential of -68.89 and 48.25 mV at pH 7.0, respectively. Results indicated the GFP gene expression and cytoplasmic accumulation of GFP protein in the transformants after incubation under desirable conditions for 48 h and 1 week. The transformation efficiency was quantitatively assayed by flow cytometry, which yielded transformations of 58.87% and 48.34% for QASSO and 38.32% and a negligible percentage for Polyfect® after 48 h and 1 week incubation, respectively.

  14. Electrochemical oxidation of quaternary ammonium electrolytes : Unexpected side reactions in organic electrochemistry

    NARCIS (Netherlands)

    Nouri Nigjeh, Eslam; de Vries, Marcel; Bruins, Andries P.; Bischoff, Rainer; Permentier, Hjalmar P.

    2012-01-01

    Quaternary ammonium salts are among the most widely used electrolytes in organic electrochemistry, but there is little known about their unwanted side oxidation reactions. We have, therefore, studied the constant potential oxidation products of quaternary ammonium electrolytes using mass spectrometr

  15. Electrochemical oxidation of quaternary ammonium electrolytes : Unexpected side reactions in organic electrochemistry

    NARCIS (Netherlands)

    Nouri Nigjeh, Eslam; de Vries, Marcel; Bruins, Andries P.; Bischoff, Rainer; Permentier, Hjalmar P.

    Quaternary ammonium salts are among the most widely used electrolytes in organic electrochemistry, but there is little known about their unwanted side oxidation reactions. We have, therefore, studied the constant potential oxidation products of quaternary ammonium electrolytes using mass

  16. Antibacterial effects of quaternary bis-phosphonium and ammonium salts of pyridoxine on Staphylococcus aureus cells: A single base hitting two distinct targets?

    Science.gov (United States)

    Nikitina, Elena V; Zeldi, Marina I; Pugachev, Mikhail V; Sapozhnikov, Sergey V; Shtyrlin, Nikita V; Kuznetsova, Svetlana V; Evtygin, Vladimir E; Bogachev, Mikhail I; Kayumov, Airat R; Shtyrlin, Yurii G

    2016-01-01

    We studied the effects of quaternary bis-phosphonium and bis-ammonium salts of pyridoxine with lipophilic substituents on the survival and morphology of Staphylococcus aureus cells. We found that, while originating from the same base, they exhibit considerably different antimicrobial mechanisms. In the presence of Ca(2+) ions the MIC and MBC values of ammonium salt increased 100-fold, suggesting that Ca(2+) ions can successfully impede the membrane Ca(2+) ions exchange required for ammonium salt incorporation. In contrast, in the presence of quaternary phosphonium salt, the artificial capsular-like material was formed around the cells and the filamentous and chain-like growth of the cells was observed suggesting the disruption of the cell division mechanisms. Altogether, both pyridoxine derivatives successfully inhibited the growth of gram-positive bacteria (Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis) and Escherichia coli considerably, while demonstrated nearly no effect against Klebsiella pneumoniae and Pseudomonas aeruginosa. We suggest that due to their effects on distinct and likely complementary targets the derivatives of pyridoxine represent potentially perspective antibacterials with complicated adaptation and thus with lower risk of drug resistance development.

  17. Influence quaternary ammonium salt in the organophilization of an bentonite; Influencia de um sal quaternario de amonio na organofilizacao de uma argila bentonitica

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, S.V.; Alves, G.P.; Wanderley, A.S.D.; Araujo, E.M., E-mail: saraveruscadeoliveira@yahoo.com.br [Universidade Federal de Campina Grande (UFCG), Campina Grande, PB (Brazil). Depto de Engenharia de Materiais

    2011-07-01

    Clays are natural materials, earthy, fine-grained particles with diameters generally less than 2μm, and formed by chemically hydrated silicates of aluminum, iron and magnesium. The clays have a range of applications, both in pottery and in other technology areas. This work aimed to study the influence of a quaternary ammonium salt to increase the basal distance of a bentonite clay powder obtained thereby promoting to a new structural profile characteristic with organoclay. The bentonite clay was treated with salt Praepragem WB. The following methods were used: X-ray diffraction (XRD) and X-ray fluorescence (XRF). The results indicated the intercalation of ammonium ions of the salt studied within the layers of silicate and expansion of basal spacing d{sub 001}, ie the clay in the study showed 2θ angle shifts to smaller angles, indicating that the clay was organophilization. (author)

  18. Synthesis, characterization and antibacterial properties of dihydroxy quaternary ammonium salts with long chain alkyl bromides.

    Science.gov (United States)

    Liu, Wen-Shuai; Wang, Chun-Hua; Sun, Ju-Feng; Hou, Gui-Ge; Wang, Yu-Peng; Qu, Rong-Jun

    2015-01-01

    Five N-methyl-N-R-N,N-bis(2-hydroxyethyl) ammonium bromides (R = -benzyl (chloride, BNQAS), -dodecyl (C12QAS), -tetradecyl (C14QAS), -hexadecyl (C16QAS), -octadecyl (C18QAS)) were prepared based on N-methyldiethanolamine (MDEA) and halohydrocarbon. Five QAS were characterized by FTIR, NMR, and MS. BNQAS, C12QAS, C14QAS, and C16QAS were confirmed by X-ray single-crystal diffraction. Their antibacterial properties indicated good antibacterial abilities against E. coli, S. aureus, B. subtilis, especially C12QAS with the best antibacterial ability (100% to E. coli, 95.65% to S. aureus, and 91.41% to B. subtilis). In addition, C12QAS also displayed the best antifungal activities than BNQAS and C18QAS against Cytospora mandshurica, Botryosphaeria ribis, Physalospora piricola, and Glomerella cingulata with the ratio of full marks. The strategy provides a facile way to design and develop new types of antibacterial drugs for application in preventing the fruit rot, especially apple. © 2014 John Wiley & Sons A/S.

  19. Reporter-free potentiometric sensing of boronic acids and their reactions by using quaternary ammonium salt-functionalized polymeric liquid membranes.

    Science.gov (United States)

    Wang, Xuewei; Yue, Dengfeng; Lv, Enguang; Wu, Lei; Qin, Wei

    2014-02-18

    The tremendous applications of boronic acids (BAs) in chemical sensing, medical chemistry, molecular assembly, and organic synthesis lead to an urgent demand for developing effective sensing methods for BAs. This paper reports a facile and sensitive potentiometric sensor scheme for heterogeneous detection of BAs based on their unexpected potential responses on quaternary ammonium salt-doped polymeric liquid membranes. (11)B NMR data reveal that a quaternary ammonium chloride can trigger the hydrolysis of an electrically neutral BA in an aprotic solvent. Using the quaternary ammonium salt as the receptor, the BA molecules can be extracted from the sample solution into the polymeric membrane phase and undergo the concomitant hydrolysis. Such salt-triggered hydrolysis generates H(+) ions, which can be coejected into the aqueous phase with the counterions (e.g., Cl(-)) owing to their high hydrophilicities. The perturbation on the ionic partition at the sample-membrane interface changes the phase boundary potential and thus enables the potentiometric sensing of BAs. In contrast to other transduction methods for BAs, for which labeled or separate reporters are exclusively required, the present heterogeneous sensing scheme allows the direct detection of BAs without using any reporter molecules. This technique shows superior detection limits for BAs (e.g., 1.0 × 10(-6) M for phenylboronic acid) as compared to previously reported methods based on colorimetry, fluorimetry, and mass spectrometry. The proposed sensing strategy has also been successfully applied to potentiometric indication of the BA reactions with hydrogen peroxide and saccharides, which allows indirect and sensitive detection of these important species.

  20. Selective detection of carbohydrates and their peptide conjugates by ESI-MS using synthetic quaternary ammonium salt derivatives of phenylboronic acids.

    Science.gov (United States)

    Kijewska, Monika; Kuc, Adam; Kluczyk, Alicja; Waliczek, Mateusz; Man-Kupisinska, Aleksandra; Lukasiewicz, Jolanta; Stefanowicz, Piotr; Szewczuk, Zbigniew

    2014-06-01

    We present new tags based on the derivatives of phenylboronic acid and apply them for the selective detection of sugars and peptide-sugar conjugates in mass spectrometry. We investigated the binding of phenylboronic acid and its quaternary ammonium salt (QAS) derivatives to carbohydrates and peptide-derived Amadori products by HR-MS and MS/MS experiments. The formation of complexes between sugar or sugar-peptide conjugates and synthetic tags was confirmed on the basis of the unique isotopic distribution resulting from the presence of boron atom. Moreover, incorporation of a quaternary ammonium salt dramatically improved the efficiency of ionization in mass spectrometry. It was found that the formation of a complex with phenylboronic acid stabilizes the sugar moiety in glycated peptides, resulting in simplification of the fragmentation pattern of peptide-derived Amadori products. The obtained results suggest that derivatization of phenylboronic acid as QAS is a promising method for sensitive ESI-MS detection of carbohydrates and their conjugates formed by non-enzymatic glycation or glycosylation.

  1. A Novel Surface Structure Consisting of Contact-active Antibacterial Upper-layer and Antifouling Sub-layer Derived from Gemini Quaternary Ammonium Salt Polyurethanes

    Science.gov (United States)

    He, Wei; Zhang, Yi; Li, Jiehua; Gao, Yunlong; Luo, Feng; Tan, Hong; Wang, Kunjie; Fu, Qiang

    2016-08-01

    Contact-active antibacterial surfaces play a vital role in preventing bacterial contamination of artificial surfaces. In the past, numerous researches have been focused on antibacterial surfaces comprising of antifouling upper-layer and antibacterial sub-layer. In this work, we demonstrate a reversed surface structure which integrate antibacterial upper-layer and antifouling sub-layer. These surfaces are prepared by simply casting gemini quaternary ammonium salt waterborne polyurethanes (GWPU) and their blends. Due to the high interfacial energy of gemini quaternary ammonium salt (GQAS), chain segments containing GQAS can accumulate at polymer/air interface to form an antibacterial upper-layer spontaneously during the film formation. Meanwhile, the soft segments composed of polyethylene glycol (PEG) formed the antifouling sub-layer. Our findings indicate that the combination of antibacterial upper-layer and antifouling sub-layer endow these surfaces strong, long-lasting antifouling and contact-active antibacterial properties, with a more than 99.99% killing efficiency against both gram-positive and gram-negative bacteria attached to them.

  2. Efficient adsorption of both methyl orange and chromium from their aqueous mixtures using a quaternary ammonium salt modified chitosan magnetic composite adsorbent.

    Science.gov (United States)

    Li, Kun; Li, Pei; Cai, Jun; Xiao, Shoujun; Yang, Hu; Li, Aimin

    2016-07-01

    A quaternary ammonium salt modified chitosan magnetic composite adsorbent (CS-CTA-MCM) was prepared by combination of Fe3O4 nanoparticles. Various techniques were used to characterize the molecular structure, surface morphology, and magnetic feature of this composite adsorbent. CS-CTA-MCM was employed for the removal of Cr(VI) and methyl orange (MO), an anionic dye, from water in respective single and binary systems. Compared with chitosan magnetic adsorbent (CS-MCM) without modification, CS-CTA-MCM shows evidently improved adsorption capacities for both pollutants ascribed to the additional quaternary ammonium salt groups. Based on the adsorption equilibrium study, MO bears more affinity to CS-CTA-MCM than Cr(VI) causing a considerable extent of preferential adsorption of dye over metal ions in their aqueous mixture. However, at weak acidic solutions, Cr(VI) adsorption is evidently improved due to more efficient Cr(VI) forms, i.e. dichromate and monovalent chromate, binding to this chitosan-based adsorbent. Thus chromium could be efficient removal together with MO at suitable pH conditions. The adsorption isotherms and kinetics indicate that adsorptions of Cr(VI) and MO by CS-CTA-MCM both follow a homogeneous monolayer chemisorption process. This magnetic adsorbent after saturated adsorption could be rapidly separated from water and easily regenerated using dilute NaOH aqueous solutions then virtually reused with little adsorption capacity loss.

  3. [Dental plaque microcosm biofilm behavior on a resin composite incorporated with nano-antibacterial inorganic filler containing long-chain alkyl quaternary ammonium salt].

    Science.gov (United States)

    Junling, Wu; Qiang, Zhang; Ruinan, Sun; Ting, Zhu; Jianhua, Ge; Chuanjian, Zhou

    2015-12-01

    To develop a resin composite incorporated with nano-antibacterial inorganic filler containing long-chain alkyl quaternary ammonium salt, and to measure its effect on human dental plaque microcosm biofilm. A novel nano-antibacterial inorganic filler containing long-chain alkyl quaternary ammonium salt was synthesized according to methods introduced in previous research. Samples of the novel nano-antibacterial inorganic fillers were modified by a coupling agent and then added into resin composite at 0%, 5%, 10%, 15% or 20% mass fractions; 0% composite was used as control. A flexural test was used to measure resin composite mechanical properties. Results showed that a dental plaque microcosm biofilm model with human saliva as inoculum was formed. Colony-forming unit (CFU) counts, lactic acid production, and live/dead assay of biofilm on the resin composite were calculated to test the effect of the resin composite on human dental plaque microcosm biofilm. The incorporation of nano-antibacterial inorganic fillers with as much as 15% concentration into the resin composite showed no adverse effect on the mechanical properties of the resin composite (P > 0.05). Resin composite containing 5% or more nano-antibacterial inorganic fillers significantly inhibited the metabolic activity of dental plaque microcosm biofilm, suggesting its strong antibacterial potency (P resin composite exhibited a strong antibacterial property upon the addition of up to 5% nano-antibacterial inorganic fillers, thereby leading to effective caries inhibition in dental application.

  4. Assessment by X-ray diffraction the process of bentonite organophilization using a different quaternary ammonium salts; Avaliacao por difracao de raios X do processo de organofilizacao de uma bentonita utilizando diferentes sais quaternarios de amonio

    Energy Technology Data Exchange (ETDEWEB)

    Silva, L.A. da; Rosario, J.A. do; Lima, R.B.; Milioli, C.C.; Gusatti, M.; Linhares, R.H.; Kuhnen, N.C.; Riella, H.G., E-mail: lasqmc@hotmail.co [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Campus Reitor Joao David Ferreira Lima; Cumbane, A.J. [Universidade Eduardo Mondlane (UEM), Maputo (Mozambique)

    2010-07-01

    The process was conducted in an organophilization Bentonite originated from the Company of Industrial Minerals of Mozambique Ltd. (Mimoc). The transformation of bentonite organophilic clay were performed in laboratory procedures that aim to mechanochemical exchange of Na{sup +} and Ca{sup 2+} from the interlayer space of clay minerals by cations of quaternary ammonium salts. In this study we used two types of salts, which are: the cetyl trimethyl ammonium chloride and alkyl dimethyl benzyl ammonium chloride at different concentrations (30, 50, 80, 100 meq/100 g clay). The natural bentonite and organophilic clay samples were characterized by X-ray diffraction (XRD) to obtain the mineralogical constituents and analysis phases of the increase in interlayer distance confirming the incorporation of quaternary ammonium salts in the structure of clays. (author)

  5. Surface Functionalization of Polyethersulfone Membrane with Quaternary Ammonium Salts for Contact-Active Antibacterial and Anti-Biofouling Properties

    Directory of Open Access Journals (Sweden)

    Xiao Hu

    2016-05-01

    Full Text Available Biofilm is a significant cause for membrane fouling. Antibacterial-coated surfaces can inhibit biofilm formation by killing bacteria. In this study, polyethersulfone (PES microfiltration membrane was photografted by four antibiotic quaternary ammonium compounds (QACs separately, which were synthesized from dimethylaminoethyl methacrylate (DMAEMA by quaternization with butyl bromide (BB, octyl bromide (OB, dodecyl bromide (DB, or hexadecyl bromide (HB. XPS, ATR-FTIR, and SEM were used to confirm the surfaces’ composition and morphology. After modification, the pores on PES-g-DMAEMA-BB and PES-g-DMAEMA-OB were blocked, while PES-g-DMAEMA-DB and PES-g-DMAEMA-HB were retained. We supposed that DMAEMA-BB and DMAEMA-OB aggregated on the membrane surface due to the activities of intermolecular or intramolecular hydrogen bonds. Bacteria testing found the antibacterial activities of the membranes increased with the length of the substituted alkyl chain. Correspondingly, little bacteria were observed on PES-g-DMAEMA-DB and PES-g-DMAEMA-HB by SEM. The antifouling properties were investigated by filtration of a solution of Escherichia coli. Compared with the initial membrane, PES-g-DMAEMA-DB and PES-g-DMAEMA-HB showed excellent anti-biofouling performance with higher relative flux recovery (RFR of 88.3% and 92.7%, respectively. Thus, surface functionalization of the PES membrane with QACs can prevent bacteria adhesion and improve the anti-biofouling activity by the contact-active antibacterial property.

  6. Synthesis and Antibacterial Activity of Novel Quaternary Ammonium Pyridoxine Derivatives.

    Science.gov (United States)

    Shtyrlin, Nikita V; Sapozhnikov, Sergey V; Koshkin, Sergey A; Iksanova, Alfiya G; Sabirov, Arthur H; Kayumov, Airat R; Nureeva, Aliya A; Zeldi, Marina I; Shtyrlin, Yurii G

    2015-01-01

    A series of 26 quaternary ammonium pyridoxine derivatives were synthesized and their cytotoxicity and antibacterial activities against clinically relevant bacterial strains were tested in vitro. The antibacterial activity of mono-ammonium salts increased with the rise of the lipophilicity and compound 3,3,5-trimethyl-8,8-dioctyl-1,7,8,9-tetrahydro-[1,3]dioxino[5,4-d]pyrrolo[3,4-b]pyridin-8-ium chloride (2d) reaches a maximum among them. Bis-ammonium salt of pyridoxine 4 with two dimethyloctylamine groups also demonstrated high antibacterial activity despite lower lipophilicity. The results of MTT assay indicated that HEK 293 cells were more sensitive than HSF to quaternary ammonium pyridoxine derivatives. Compounds 2d and 4 did not induce the damage of the DNA and might be of interest in the development of new antimicrobials.

  7. In vitro antibacterial activity of a novel resin-based pulp capping material containing the quaternary ammonium salt MAE-DB and Portland cement.

    Directory of Open Access Journals (Sweden)

    Yanwei Yang

    Full Text Available BACKGROUND: Vital pulp preservation in the treatment of deep caries is challenging due to bacterial infection. The objectives of this study were to synthesize a novel, light-cured composite material containing bioactive calcium-silicate (Portland cement, PC and the antimicrobial quaternary ammonium salt monomer 2-methacryloxylethyl dodecyl methyl ammonium bromide (MAE-DB and to evaluate its effects on Streptococcus mutans growth in vitro. METHODS: The experimental material was prepared from a 2 : 1 ratio of PC mixed with a resin of 2-hydroxyethylmethacrylate, bisphenol glycerolate dimethacrylate, and triethylene glycol dimethacrylate (4 : 3 : 1 containing 5 wt% MAE-DB. Cured resin containing 5% MAE-DB without PC served as the positive control material, and resin without MAE-DB or PC served as the negative control material. Mineral trioxide aggregate (MTA and calcium hydroxide (Dycal served as commercial controls. S. mutans biofilm formation on material surfaces and growth in the culture medium were tested according to colony-forming units (CFUs and metabolic activity after 24 h incubation over freshly prepared samples or samples aged in water for 6 months. Biofilm formation was also assessed by Live/Dead staining and scanning electron microscopy. RESULTS: S. mutans biofilm formation on the experimental material was significantly inhibited, with CFU counts, metabolic activity, viability staining, and morphology similar to those of biofilms on the positive control material. None of the materials affected bacterial growth in solution. Contact-inhibition of biofilm formation was retained by the aged experimental material. Significant biofilm formation was observed on MTA and Dycal. CONCLUSION: The synthesized material containing HEMA-BisGMA-TEGDMA resin with MAE-DB as the antimicrobial agent and PC to support mineralized tissue formation inhibited S. mutans biofilm formation even after aging in water for 6 months, but had no inhibitory effect on

  8. N,N-Dimethyltryptamine and dichloromethane: rearrangement of quaternary ammonium salt product during GC-EI and CI-MS-MS analysis.

    Science.gov (United States)

    Brandt, Simon D; Martins, Cláudia P B; Freeman, Sally; Dempster, Nicola; Wainwright, Mark; Riby, Philip G; Alder, John F

    2008-05-12

    N,N-Dimethyltryptamine (DMT) 1 is a simple tryptamine derivative with powerful psychoactive properties. It is abundant in nature and easily accessible through a variety of synthetic routes. Most work-up procedures require the use of organic solvents and halogenated representatives are often employed. DMT was found to be reactive towards dichloromethane, either during work-up or long term storage therein, which led to the formation of the quaternary ammonium salt N-chloromethyl-DMT chloride 2. Analysis of this side-product by gas chromatography ion trap mass spectrometry (GC-MS), both in electron and chemical ionisation tandem MS modes, gave only degradation products. For example, 2 could not be detected but appeared to have rearranged to 3-(2-chloroethyl)indole 3 and 2-methyltetrahydro-beta-carboline 4, whereas HPLC analysis enabled the detection of 2. GC-MS is a standard tool for the fingerprinting of drug products. The identification of a particular synthetic route is based on the analysis of impurities, provided these side products can be established to be route-specific. The in situ detection of both 3 and 4 within a DMT sample may have led to erroneous conclusions with regards to the identification of the synthetic route.

  9. Cr(VI) sorption behavior from aqueous solutions onto polymeric microcapsules containing a long-chain quaternary ammonium salt: Kinetics and thermodynamics analysis

    Energy Technology Data Exchange (ETDEWEB)

    Barassi, Giancarlo; Valdes, Andrea; Araneda, Claudio; Basualto, Carlos; Sapag, Jaime; Tapia, Cristian [Laboratorio de Operaciones Unitarias, Facultad de Ciencias Quimicas y Farmaceuticas, Universidad de Chile, Av. Vicuna Mackenna 20, Santiago (Chile); Valenzuela, Fernando, E-mail: fvalenzu@uchile.cl [Laboratorio de Operaciones Unitarias, Facultad de Ciencias Quimicas y Farmaceuticas, Universidad de Chile, Av. Vicuna Mackenna 20, Santiago (Chile)

    2009-12-15

    This work studies the adsorption of Cr(VI) ions from an aqueous acid solution on hydrophobic polymeric microcapsules containing a long-chain quaternary ammonium salt-type extractant immobilized in their pore structure. The microcapsules were synthesized by adding the extractant Aliquat 336 during the in situ radical copolymerization of the monomers styrene (ST) and ethylene glycol dimethacrylate (EGDMA). The microcapsules, which had a spherical shape with a rough surface, behaved as efficient adsorbents for Cr(VI) at the tested temperatures. The results of kinetics experiments carried out at different temperatures showed that the adsorption process fits well to a pseudo-second-order with an activation energy of 82.7 kJ mol{sup -1}, confirming that the sorption process is controlled by a chemisorption mechanism. Langmuir's isotherms were found to represent well the experimentally observed sorption data. Thermodynamics parameters, namely, changes in standard free energy ({Delta}G{sup 0}), enthalpy ({Delta}H{sup 0}), and entropy ({Delta}S{sup 0}), are also calculated. The results indicate that the chemisorption process is spontaneous and exothermic. The entropy change value measured in this study shows that metal adsorbed on microcapsules leads to a less chaotic system than a liquid-liquid extraction system.

  10. PRN 88-2: Clustering of Quaternary Ammonium Compounds

    Science.gov (United States)

    This Notice announces that EPA has clustered the Quaternary Ammonium Compounds into four groups for the purpose of testing chemicals to build a database that will support continued registration of the entire family of quaternary ammonium compounds

  11. Preparation of chitosan quaternary ammonium salt in ionic liquid and its flocculating effect%离子液体中制备壳聚糖季铵盐及其絮凝效果研究

    Institute of Scientific and Technical Information of China (English)

    张聪璐; 胡筱敏; 祝雷; 王芳

    2013-01-01

    Ionic liquid of glycine hydrochloride has been synthesized through one-step synthesis.And chitosan quaternary ammonium salt has been made from quaternary ammonium reaction of 2,3-epoxypropyltrimethyl ammonium chloride and chitosan,with glycine hydrochloride aqueous solution as medium.Then it is applied to the treatment of traditional Chinese medicine wastewater.The effects of various reaction parameters,such as reaction temperature,reaction time,mass ratio of reactants and concentration of ionic liquid on the substitution degree of quatemary ammonium salt,as well as the effects of quaternary ammonium salt dosage,pH,stirring time on flocculating efficacy are investigated.The results show that both of the reaction efficacy of quaternary ammonium in ionic liquid and the degree of substitution of the product are higher than that of conventional non-homogeneous reaction.Chitosan quaternary ammonium salt could effectively remove the turbidity and COD from traditional Chinese medicine wastewater.%采用一步合成法制备了离子液体甘氨酸盐酸盐,以其水溶液为反应介质,壳聚糖与2,3-环氧丙基三甲基氯化铵进行季铵化反应,得到壳聚糖季铵盐,并将其用于中药废水的絮凝处理.考察了温度、时间、反应物配比及离子液体浓度对季铵盐取代度的影响,以及季铵盐加入量、pH、搅拌时间对絮凝效果的影响.实验结果表明,在离子液体中进行的季铵化反应效率及产品取代度均高于常规的非均相反应,壳聚糖季铵盐能够有效去除中药废水的浊度和COD.

  12. QSAR modeling of mono- and bis-quaternary ammonium salts that act as antagonists at neuronal nicotinic acetylcholine receptors mediating dopamine release.

    Science.gov (United States)

    Zheng, Fang; Bayram, Ersin; Sumithran, Sangeetha P; Ayers, Joshua T; Zhan, Chang-Guo; Schmitt, Jeffrey D; Dwoskin, Linda P; Crooks, Peter A

    2006-05-01

    Back-propagation artificial neural networks (ANNs) were trained on a dataset of 42 molecules with quantitative IC50 values to model structure-activity relationships of mono- and bis-quaternary ammonium salts as antagonists at neuronal nicotinic acetylcholine receptors (nAChR) mediating nicotine-evoked dopamine release. The ANN QSAR models produced a reasonable level of correlation between experimental and calculated log(1/IC50) (r2=0.76, r(cv)2=0.64). An external test for the models was performed on a dataset of 18 molecules with IC50 values >1 microM. Fourteen of these were correctly classified. Classification ability of various models, including self-organizing maps (SOM), for all 60 molecules was also evaluated. A detailed analysis of the modeling results revealed the following relative contributions of the used descriptors to the trained ANN QSAR model: approximately 44.0% from the length of the N-alkyl chain attached to the quaternary ammonium head group, approximately 20.0% from Moriguchi octanol-water partition coefficient of the molecule, approximately 13.0% from molecular surface area, approximately 12.6% from the first component shape directional WHIM index/unweighted, approximately 7.8% from Ghose-Crippen molar refractivity, and 2.6% from the lowest unoccupied molecular orbital energy. The ANN QSAR models were also evaluated using a set of 13 newly synthesized compounds (11 biologically active antagonists and two biologically inactive compounds) whose structures had not been previously utilized in the training set. Twelve among 13 compounds were predicted to be active which further supports the robustness of the trained models. Other insights from modeling include a structural modification in the bis-quinolinium series that involved replacing the 5 and/or 8 as well as the 5' and/or 8' carbon atoms with nitrogen atoms, predicting inactive compounds. Such data can be effectively used to reduce synthetic and in vitro screening activities by eliminating

  13. 21 CFR 172.165 - Quaternary ammonium chloride combination.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Quaternary ammonium chloride combination. 172.165... HUMAN CONSUMPTION Food Preservatives § 172.165 Quaternary ammonium chloride combination. The food additive, quaternary ammonium chloride combination, may be safely used in food in accordance with...

  14. Synthesis and Solution Properties of Adamantane Containing Quaternary Ammonium Salt-type Cationic Surfactants: Hydrocarbon-based, Fluorocarbonbased and Bola-type.

    Science.gov (United States)

    Yoshimura, Tomokazu; Okada, Mari; Matsuoka, Keisuke

    2016-10-01

    Quaternary ammonium salt-type cationic surfactants with an adamantyl group (hydrocarbon-type; CnAdAB, fluorocarbon-type; Cm(F)C3AdAB, bola-type; Ad-s-Ad, where n, m and s represent hydrocarbon chain lengths of 8-16, fluorocarbon chain lengths of 4-8, and spacer chain length of 10-12) were synthesized via quaternization of N, N-dimethylaminoadamantane and n-alkyl bromide or 1, n-dibromoalkane. Conductivity and surface tension were measured to characterize the solution properties of the synthesized adamantyl group-containing cationic surfactants. In addition, the effects of hydrocarbon and fluorocarbon chain lengths and spacer chain length between headgroups on the measured properties were evaluated by comparison with those of conventional cationic surfactants. The critical micelle concentration (CMC) of CnAdAB and Ad-s-Ad was 2/5 of that for the corresponding conventional surfactants CnTAB and bola-type surfactants with similar number of carbons in the alkyl or alkylene chain; this was because of the increased hydrophobicity due to the adamantyl group. A linear relationship between the logarithm of CMC and the hydrocarbon chain length for CnAdAB was observed, as well as for CnTAB. The slope of the linear correlation for both surfactants was almost the same, indicating that the adamantyl group does not affect the CMC with variations in the hydrocarbon chain length. Similar to conventional surfactants CnTAB, the hydrocarbon-type CnAdAB is highly efficient in reducing the surface tension of water, despite the large occupied area per molecule resulting from the relatively bulky structure of the adamantane skeleton. On the other hand, the bola-type Ad-s-Ad resulted in increased surface tension compared to CnAdAB, indicating that the curved chain between adamantyl groups leads to poor adsorption and orientation at the air-water interface.

  15. CO2/pH-Controllable Viscoelastic Nanostructured Fluid Based on Stearic Acid Soap and Bola-Type Quaternary Ammonium Salt.

    Science.gov (United States)

    Zhang, Yongmin; Kong, Weiwei; An, Pengyun; He, Shuai; Liu, Xuefeng

    2016-03-15

    Fatty acid soaps such as sodium stearate (NaOSA) represent a class of cheap, environmentally friendly surfactants; however, their poor solubility seriously challenges their application in various fields. Herein, we describe a CO2/pH-controllable viscoelastic nanostructured fluid, which was developed by simple mixing of the commodity soap NaOSA with a bola-type quaternary ammonium salt (Bola2be) in a 2:1 molar ratio without the need for complex organic synthesis. The introduction of Bola2be increased NaOSA solubility and promoted micelle growth by forming a noncovalent pseudo-Gemini structure, 2NaOSA-Bola2be. Long aggregates are formed with increases in concentration, and these become entangled into a three-dimensional network at 10 times that of the critical micelle concentration (0.057 mM), showing strong thickening ability. Micellar branching occurs above 22.38 mM, as deduced by rheology and verified by cryo-transmission electron microscopy. The worm-based fluid formed from the noncovalent pseudo-Gemini surfactant is highly thermosensitive, and features a higher flow activation energy of 399.76 kJ·mol(-1) compared with common worm systems. Because of the pH-sensitivity of NaOSA, the viscoelastic fluid can respond to common pH stimuli or green CO2 gas, and shows a transition between a gel-like wormlike micellar network and a water-like dispersion with precipitate. However, the CO2-responsive behavior is irreversible.

  16. 超支化聚酯季铵盐的合成与表征%Synthesis and characterization of quaternary ammonium salt of hyperbranched polyester

    Institute of Scientific and Technical Information of China (English)

    杜英英; 陈倩兰; 邢彦军; 戴瑾瑾

    2011-01-01

    In the presence of alkaline catalyst sodium hydroxide, quaternary ammonium salt of hyperbranched polyester (GTA-H20) was prepared by the modification of hyperbranched polyester Boltorn H20 with glycidyltrimethylammonium chloride (GTA).The influences of reaction conditions on the yield of product were studied.The results showed that under the conditions of n(H20):n(GTA)=1 :16, n(NaOH)/n(H20-OH)=0.5, 50 ℃ of reaction temperature and 24 h of reaction time, the product 61.11 % of yield was obtained.The element analysis indicated that the substitution degree of GTA was 22.32%, and the structure of the product was characterized by iH NMH,FT-IR and 13C NMR.%在氢氧化钠催化条件下,利用缩水甘油三甲基氯化铵(GTA)对端羟基超支化聚酯Boltom H20进行季铵化改性,得到了超支化聚酯季铵盐GTA-H20,研究了反应条件对产率的影晌,结果表明:当n(H20):n(GTA)=1:16,n(NaOH)/n(H20-OH)=0.5,50℃反应24h,产率为61.11%.元素分析结果表明:此时GTA的取代度为22.32%,并用(1)H NMR、FF-IR和(13)C NMR谱图对GTA-H20进行了表征.

  17. Combinatorial materials research applied to the development of new surface coatings XV: an investigation of polysiloxane anti-fouling/fouling-release coatings containing tethered quaternary ammonium salt groups.

    Science.gov (United States)

    Majumdar, Partha; Crowley, Elizabeth; Htet, Maung; Stafslien, Shane J; Daniels, Justin; VanderWal, Lyndsi; Chisholm, Bret J

    2011-05-09

    As part of ongoing efforts aimed at the development of extensive structure−property relationships for moisture-curable polysiloxane coatings containing tethered quaternary ammonium salt (QAS) moieties for potential application as environmental friendly coatings to combat marine biofouling, a combinatorial/high-throughput (C/HT) study was conducted that was focused on four different compositional variables. The coatings that were investigated were derived from solution blends of a silanol-terminated polydimethylsiloxane (HO-PDMS-OH), QAS-functional alkoxysilane, and methyltriacetoxysilane. The compositional variables investigated were alkoxysilane functionality of the QAS-functional silane, chain length of the monovalent alkyl group attached to the QAS nitrogen atom, concentration of the QAS-functional alkoxysilane, and molecular weight of the HO-PDMS-OH. Of these variables, the composition of the alkoxysilane functionality of the QAS-functional silane was a unique variable that had not been previously investigated. The antifouling (AF) and fouling-release (FR) characteristics of the 24 unique coating compositions were characterized using HT assays based on three different marine microorganisms, namely, the two bacteria, Cellulophaga lytica and Halomonas pacifica, and the diatom, Navicula incerta. Coatings surfaces were characterized by surface energy, water contact angle hysteresis, and atomic force microscopy (AFM). A wide variety of responses were obtained over the compositional space investigated. ANOVA analysis showed that the compositional variables and their interactions significantly influenced AF/FR behaviors toward individual marine microorganisms. It was also found that utilization of the ethoxysilane-functional QASs provided enhanced AF character compared to coatings based on methoxysilane-functional analogues. This was attributed to enhanced surface segregation of QAS groups at the coating-air interface and confirmed by phase images using AFM.

  18. Determination of aluminium in water samples by adsorptive cathodic stripping voltammetry in the presence of pyrogallol red and a quaternary ammonium salt.

    Science.gov (United States)

    Arancibia, Verónica; Muñoz, Carolina

    2007-09-30

    A fast, sensitive and selective method for the determination of aluminium based on the reaction of the metal with pyrogallol red (PR) in the presence of tetrabutylammonium tetrafluoroborate (TBATFB) to form an Al(PR)(3)x9TBATFB complex which is adsorbed on the mercury electrode is presented. Under these conditions complexation of aluminium is rapid and no waiting period or heating of the sample is required. The reduction current of the accumulated complex is measured by scanning the potential in the cathodic direction. The variation of peak current with pH, adsorption time, adsorption potential, ligand and quaternary ammonium salt concentration, and some instrumental parameters, such as stirring rate in the accumulation stage, and step amplitude, pulse amplitude and step duration while obtaining the square wave voltamperograms were optimized. The best experimental parameters were pH 8.5, (NH(4)Ac-NH(3) buffer), C(PR)=25mumolL(-1), C(TBATFB) over 75mumolL(-1), t(ads)=60s, and E(ads)=-0.60V versus Ag/AgCl. A linear response is observed over the 0.0-30.0mugL(-1) concentration range, with a detection limit of 1.0mugL(-1). Reproducibility for 9.0mugL(-1) aluminium solution was 2.3% (n=6). Synthetic sea water and sea water reference material CRM-SW were used for validation measurements. Aluminium in urine samples of a volunteer who ingested 800mg of Al(OH)(3) was analyzed.

  19. Antibacterial activity of a modified unfilled resin containing a novel polymerizable quaternary ammonium salt MAE-HB

    Science.gov (United States)

    Huang, Li; Yu, Fan; Sun, Xiang; Dong, Yan; Lin, Ping-ting; Yu, Hao-han; Xiao, Yu-hong; Chai, Zhi-guo; Xing, Xiao-dong; Chen, Ji-hua

    2016-01-01

    Resins with strong and long-lasting antibacterial properties are critical for the prevention of secondary dental caries. In this study, we evaluated the antibacterial effect and the underlying mechanism of action of an unfilled resin incorporating 2-methacryloxylethyl hexadecyl methyl ammonium bromide (MAE-HB) against Streptococcus mutans UA159 (S. mutans UA159). MAE-HB was added into unfilled resin at 10 mass%, and unfilled resin without MAE-HB served as the control. Bacterial growth was inhibited on 10%-MAE-HB unfilled resin compared with the control at 1 d, 7 d, 30 d, or 180 d (P  0.05). No significant differences in the antibacterial activities of eluents from control versus 10%-MAE-HB unfilled resins were observed at any time point (P > 0.05). The number of bacteria attached to 10%-MAE-HB unfilled resin was considerably lower than that to control. Fe-SEM and CLSM showed that 10%-MAE-HB unfilled resin disturbed the integrity of bacterial cells. Expression of the bacterial glucosyltransferases, gtfB and gtfC, was lower on 10%-MAE-HB unfilled resin compared to that on control (P S. mutans. PMID:27659279

  20. 低碳链季铵盐定量分析方法的改进%Improvement of quantitative analysis method for short-carbon-chain quaternary ammonium salt

    Institute of Scientific and Technical Information of China (English)

    吴文桢; 屈撑囤; 张世君; 杨志刚

    2009-01-01

    In order to make quantitative analysis for the short-carbon-chain quaternary ammonium salt, the method of "dodecyl dimethyl ammonium chloride quantitative analysis" in the standard(HG/T2230-2006)was improved and investigated by adopting the sodium tetraphenyl boron back titrimetry. Based on gravimetric method, the accuracy of the analysis results was inspected. According to the error analysis of the measuring results, the reproducibility of this improved method was discussed. Meanwhile, the different-carbon-chain quaternary ammonium salt was quantitatively analyzed. The result shows that as the mass fraction of short-carbon-chain quaternary ammonium salt molecular is more than 0.1%, the sodium tetraphenyl boron back titrimetry that improves the method in HG/T2230-2006 has good accuracy and repeatability, the accuracy rate of analysis result is above 99.5 %.%为了对低碳链季铵盐进行定量分析,应用四苯硼钠返滴定法对(HG/T 2230-2006)标准中低碳链季铵盐质量分数进行了分析改进研究.以重量法为基准对分析结果的准确性进行了检验,通过测定结果的误差分析,对方法的重现性进行了探讨,同时对不同碳链季铵盐进行了定量分析.结果表明,当低碳链季铵盐分子的质量分数在0.1%以上时,应用(HG/T 2230-2006)标准分析低碳链季铵盐质量分数的改进方法重现性好,准确率为99.5%以上.

  1. 季铵盐-高岭石系列插层复合物的制备及结构表征%Preparation and Structural Characterization of Kaolinite Intercalation Compounds with Series of Quaternary Ammonium Salt

    Institute of Scientific and Technical Information of China (English)

    刘钦甫; 王定; 郭鹏; 张帅; 程宏飞; 李晓光; 张士龙

    2015-01-01

    通过多次置换插层反应,以高岭石/甲醇插层复合物为中间体,将不同链长季铵盐分子插入高岭石层间,对其结构、形貌和插层机理进行了探讨。结果表明:季铵盐分子在高岭石层间主要以全反转式构形存在,季铵盐碳链长度对其插层复合体的结构和形貌具有明显控制作用。碳原子数小于8的季铵盐在高岭石层间以单层平卧形式存在,其形成的高岭石插层复合体晶形仍为片状;碳原子数大于等于8的季铵盐在高岭石层间呈石蜡型倾斜双层形式排列,且碳链与高岭石(001)晶面的夹角随碳原子数增大而减小。碳原子数大于等于8的季铵盐进入高岭石层间,将导致高岭石晶层的卷曲,形成纳米卷或管,且随季铵盐碳链长度增加,高岭石片层卷曲程度加深,纳米卷的数量增多。%Kaolinite intercalation compounds with series quaternary ammonium salt prepared through displacement intercalation were characterized.The intercalation mechanism, the arrangement of quaternary ammonium salts between kaolinite layers and the thermal stability and morphology of intercalation complexes were investigated. The results show that the quaternary ammonium salts between kaolinite layers mainly arrange as all-trans configuration, and their carbon chain length has a significant effect on the structure and morphology of intercalation complexes. The quaternary ammonium slats with short carbon chains (i.e., the carbon number was<8) mainly form a monolayer structure in kaolinite interlayer, and the morphology of intercalation complexes remains flat. When the quaternary ammonium salts with relative longer carbon chains (i.e., the carbon number was ³8) mainly arrange in a paraffin-type bilayer structure, the angle between the carbon chain and (001) plane of kaolinite gradually decreases with the increase of the carbon number. In addition, kaolinite platelet beginsto crimp and even develops to

  2. 壳聚糖季铵盐的制备及其在纺织品上的应用进展%Preparation of quaternary ammonium salt of chitosan and its latest application development in textiles

    Institute of Scientific and Technical Information of China (English)

    何雪梅; 张孟龙

    2011-01-01

    介绍了壳聚糖季铵盐的制备方法以及在纺织品上的应用进展.壳聚糖季铵盐衍生物克服了壳聚糖自身溶解性差的缺点,具有典型季铵盐的性质如抗萄抑菌性、固色匀染性、吸湿保湿性等,因其价廉、无毒、生物相容性良好、易降解等,在纺织品加工领域有着潜在的应用价值.%The preparation methods of quaternary ammonium salt of chitosan and its application in textiles were introduced.Quaternary chitosan derivatives overcome the shortcoming of poor water solubility of chitosan,have typical properties of quaternary ammonium salt including anti-bacterial, fixing and level-dyeing property,moisture absorption and retention properly.Chitosan had potential application value in textile processing field due to its low cost, nontoxicity, good biocompatibility and biodegradability.

  3. κ-阿片受体激动剂U50 488H的季胺化改造%Structural transformation of κ-opioid receptor agonist (US0 488H) to quaternary ammonium salt

    Institute of Scientific and Technical Information of China (English)

    王倩梅; 贾敏; 冯娜; 张淑苗; 李娟; 樊荣; 王跃民; 裴建明

    2013-01-01

    AIM: To reduce the potential addiction of U50 488H, a κ-opioid receptor agonist, by structurally transforming it to its quaternary ammonium salt incapable of going through the blood-brain barrier. METHODS: U50 488H was transformed to its quaternary ammonium salt, which was identified with mass spectrometry. The concentrations of U50 488H and its quaternary ammonium salt in serum and brain tissue were determined by chromatography. RESULTS: The quaternary ammonium salt of U50 488H was a faint yellow powder and mass spectrometry proved it to be C20H29Cl2IN2O, with remarkably increased solubility than U50 488H. Chromatography detected U50 488H in both serum and brain tissue fluid of the rats after i. v. injection. However, quaternary ammonium salt of U50 488H was detected only in serum and not in brain tissue. CONCLUSION: The structural transformation of U50 488H to its quaternary ammonium salt incapable of going through the blood-brain barrier reduces the potential addiction of U50 488H.%目的:通过对κ-阿片受体激动剂U50 488H的结构进行季胺化改造,使其不能通过血脑屏障,从而消除可能存在的成瘾和依赖性.方法:对U50 488H进行季胺化改造,使用质谱法确认该季胺化产物,使用高效液相色谱法对比测定U50 488H及改造后的季胺化U50 488H在血清和脑中的浓度.结果:季胺化后的U50 488H呈淡黄色粉末样,经质谱分析,确认所得产物为U50 488H的碘甲烷季铵盐C20 H29 Cl2IN2O.后者溶解度较U50 488H明显增大.分别静脉注射U50 488H或季胺化U50 488H后,经色谱分析在血清中均可检测到所注射的药物;而在脑组织液中可以检测到U50 488H,却检测不到季胺化U50 488H.结论:成功改造获得一种新的化合物季胺化U50 488H,该物质不能通过血脑屏障,可以避免因U50 488H通过血液循环进入脑组织引起的成瘾和依赖性.

  4. Improved method for the determination of trace quaternary ammonium salt by high performance liquid chromatography%高效液相色谱法测定微量季铵盐的改进方法

    Institute of Scientific and Technical Information of China (English)

    卢姝; 纪然

    2011-01-01

    利用季铵盐与间硝基酚反应生成溶于有机溶剂的络合物,该络合物可以用紫外检测器进行定量分析,建立了一种高效液相色谱测定微量季铵盐的改进方法.该方法的线性范围为0.60~99.40 mg/L,最低检出限可达0.4mg/L,平均回收率为94.97%~104.02%,相对标准偏差为3.41%.该方法稳定、简便且灵敏度高,适于测定锅炉循环冷却水、工业废水及水处理药剂中季铵盐类阳离子表面活性剂的含量.%Quaternary ammonium salt and 3-nitrophenol have been used for preparing the complex compound which is soluble in organic solvent. The complex compound can be determined quantitatively with UV detector. An improved method for the determination of trace quaternary ammonium salt by the high performance liquid chromatography is established. The linear range of the method is 0.60-99.40 mg/L. Its lowest detection limit 0.4 mg/L, average recovery rate 94.97%-104.02% and relative standard deviation 3.41%. The method is rapid, convenient and highly sensitive. It is suitable for the determination of the content of cationic surfactant of quaternary ammonium salts in circulating cooling water, industrial wastewater and water treatment agents.

  5. 镉试剂分光光度法测定季铵盐型阳离子表面活性剂%Spectrophotometric determination of quaternary ammonium salt type cationic surfactants with cadion NPPAPT

    Institute of Scientific and Technical Information of China (English)

    李美蓉; 孙方龙; 郭长会; 刘慧英; 黄银; 刘晓青

    2012-01-01

    基于季铵盐型阳离子表面活性剂与1 -(4-硝基苯基)-3-[4-(苯基偶氮)苯基]三氮烯(镉试剂,NPPAPT)发生显色反应,建立了一种镉试剂分光光度法测定聚环氧丙烷季铵盐型表面活性剂(CP - 60)的方法.测试结果表明,测定的最大吸收波长为382 nm,CP - 60的质量浓度在0~0.13 mg·L-1内,符合比尔定律;将该方法直接应用于相对分子质量较小的十二烷基二甲基苄基氯化铵(1227)和十六烷基溴化吡啶(CPB)的测定,同样获得了满意的结果.%Based on chromogenic reaction of quaternary ammonium salt type cationic surfactants with 1 - (4 -nitrophenyl) -3 - (4 - phenylazophenyl) triazene (cadion NPPAPT) ,a new method for spectrophotometric determination of polypropylene oxide quaternary ammonium salt type cationic surfactant ( CP - 60) was established. Test results showed that the maximum wavelength is 382 nm. Within range of mass concentration of surfactant solution 0 ~ 0. 13 mg · L-1, the relationship between the absorption and the concentration follows Beer's law. This method was directly applied to quaternary ammonium salt type cationic surfactants of the smaller relative molecular weight such as dodecyldimethylbenzylammonium chloride ( 1227 ) and cetylpyridinium bromide (CPB) ,and satisfactory results were also obtained.

  6. Capacitive Properties of Polyaniline Electrodes Doped with Quaternary Ammonium Salts%季铵盐掺杂聚苯胺电极的电容性能

    Institute of Scientific and Technical Information of China (English)

    张淑英; 温柳青; 武克忠

    2013-01-01

    Polyaniline electrodes doped with quaternary ammonium salts [CnH2n+1N (CH3) 3] Cl (n =12,14,16,18) were prepared by cyclic voltammetry.The surface morphology and the structures of composite electrodes were characterized by scanning electron microscope (SEM) and Fourier transform infrared spectroscopy(FTIR).The electrochemical properties of electrodes and the capacitive behavior of the resulting capacitors were systematically studied using cyclic voltammetry(CV),electrochemical impedance spectroscopy (EIS) and constant current charge discharge tests.The specific capacitance of polyaniline electrode doped with [C18H37N(CH3) 3] CI exhibits a value as high as 329.6 F/g,higher than the value of 199.0 F/g for the PANI electrode at a constant current of 2 × 10-3 A.Moreover,the PANI/C18C3 electrodes retain good stability over 30 charge-discharge tests with a specific capacitance of 252.4 F/g.%采用循环伏安法,在铂电极表面聚合制备了季铵盐[CnH2n+1N(CH3)3]Cl(n=12,14,16,18)掺杂的聚苯胺修饰电极.利用扫描电子显微镜、红外光谱以及X射线衍射对复合电极的表面形貌和结构进行了表征.用循环伏安法、交流阻抗和恒电流充放电测试对电极的电化学性质和电容行为进行了系统研究.结果表明,其中[C18H37N(CH3)3]Cl季铵盐掺杂的聚苯胺复合电极比表面积大,电容性能好,在2×10-3 A的充电电流下,初始比电容高达329.6 F/g,未掺杂电极比电容为199.0 Wg.而且,复合电极的循环稳定性良好,经30次循环后比电容保持为252.4 F/g.

  7. Synthesis of novel quaternary ammonium surfactants containing adamantane

    Institute of Scientific and Technical Information of China (English)

    Jian Wei Guo; Xing Zhong; Hua Zhu; Li Juan Feng; Ying De Cui

    2012-01-01

    A series of novel quaternary ammonium surfactants containing adamantane were designed and synthesized from 1-adamantanecarboxylic acid.The structures of target surfactants were confirmed by 1H NMR,elements analysis and FTIR.Surface properties of these surfactants were investigated.Due to the lipophilicity of adamantane,the critical micelle concentration (CMC) and C20 values of the synthesized quaternary ammonium surfactants are lower than that of conventional quaternary ammonium surfactants.

  8. Efficient cellulose solvent: quaternary ammonium chlorides.

    Science.gov (United States)

    Kostag, Marc; Liebert, Tim; El Seoud, Omar A; Heinze, Thomas

    2013-10-01

    Pure quaternary tetraalkylammonium chlorides with one long alkyl chain dissolved in various organic solvents constitute a new class of cellulose solvents. The electrolytes are prepared in high yields and purity by Menshutkin quaternization, an inexpensive and easy synthesis route. The pure molten tetraalkylammonium chlorides dissolve up to 15 wt% of cellulose. Cosolvents, including N,N-dimethylacetamide (DMA), may be added in large excess, leading to a system of decreased viscosity. Contrary to the well-established solvent DMA/LiCl, cellulose dissolves in DMA/quaternary ammonium chlorides without any pretreatment. Thus, the use of the new solvent avoids some disadvantages of DMA/LiCl and ionic liquids, the most extensively employed solvents for homogeneous cellulose chemistry.

  9. Quaternary ammonium compounds – New occupational hazards

    Directory of Open Access Journals (Sweden)

    Agnieszka Lipińska-Ojrzanowska

    2014-10-01

    Full Text Available Quaternary ammonium compounds (QACs, quats belong to organic ionic chemical agents which display unique properties of both surfactants and disinfectants. Their wide distribution in the work environment and also in private households brings about new occupational hazards. This paper reviews reports about the health effects of QACs. QACs could play a role of sensitizers and irritants to the skin and mucous membranes. It is suspected that particular QACs can display an immunologic crossreactivity between each other and with other chemical compounds containing ammonium ion, such as muscle relaxants widely used in anesthesia. They may promote the development of airway allergy, however, the background mechanisms are still unclear and need to be further investigated. Until now, a few cases of occupational asthma induced by QACs have been described and their involvement in contact dermatitis has been documented. The possibility of anaphylaxis due to QACs cannot be excluded as well. Med Pr 2014;65(5:675–682

  10. Temperature influencing study on germicidal efficacy of quaternary ammonium salt disinfectants to bacterial spores%温度对季铵盐消毒液杀灭细菌芽孢效果影响的研究

    Institute of Scientific and Technical Information of China (English)

    陈越英; 吴晓松; 张伟; 范晶晶; 谈智; 王嵬; 徐燕

    2016-01-01

    Objective To study temperature influencing germicidal efficacy of quaternary ammonium salt disinfectants to spores of bacteria. Methods Suspension quantitative germicidal test was used to observe the efficacy of quaternary ammo-nium salt disinfectants to spores of Bacillus subtilis var. niger under different temperature. Results The quaternary ammoni-um salt disinfectants have no efficacy in killing spores of Bacillus subtilis var. niger when the temperature≤40℃. The ger-micidal efficacy of these three quaternary ammonium salt disinfectants to spores of Bacillus subtilis var. niger were gradually and significantly improved while the temperature increased from 40℃ to 60℃. The average reduction logarithm value of spores of Bacillus subtilis var. niger exposed to nutmeg and didoctyl for 2 and 3 hours were all>5 when the temperature in-creased to 80℃,which met the high-efficacy disinfectant standard. Conclusion The germicidal efficacy of these three quaternary ammonium salt disinfectants to spores of Bacillus subtilis var. niger are significantly increased when temperature increasing above 40℃.%目的:研究温度对季铵盐类消毒液杀灭细菌芽孢效果的影响。方法采用悬液定量杀菌试验方法,观察不同温度条件下季铵盐消毒液对枯草杆菌黑色变种芽孢杀灭效果。结果季铵盐消毒液在≤40℃时,对枯草杆菌黑色变种芽孢几乎无杀灭作用。三种季铵盐消毒液在温度升到60℃时,对悬液内枯草杆菌黑色变种芽孢杀灭效果逐渐达到明显提升。将作用温度升到80℃时作用2 h和3 h,肉豆蔻和双辛葵基对悬液内枯草杆菌黑色变种芽孢杀灭对数值均>5.0,达到高效消毒要求;而十二烷基在相同条件下对枯草杆菌黑色变种芽孢杀灭对数值仅为3.87。结论三种季铵盐类消毒液在作用温度升到40℃以上,随着温度升高对枯草杆菌黑色变种芽孢的杀灭效果均明显增强。

  11. Synthesis and characterization of chitosan based dye containing quaternary ammonium group.

    Science.gov (United States)

    Tang, Ruilin; Zhang, Ying; Zhang, Yang; Yu, Zhiming

    2016-03-30

    A new antimicrobial biopolymer dye was synthesized by reaction of quaternary ammonium salt of chitosan and reactive red x-3b. And quaternary ammonium salt of chitosan was produced by grafting glycidyltrimethylammonium chloride on chitosan. The synthesized materials were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), solubility test and antimicrobial test. Results show that the antimicrobial biopolymer dye was combined by N(+)(CH3)3 of quaternary ammonium salt of chitosan and sulfonic group of reactive red x-3b. Water solubility of chitosan biopolymer dye was increased as well as pH value. In addition, antibacterial property of new synthesized dye was excellent, whose antibacterial rates of Staphylococcus and Escherichia coli were both bigger than 99%. These results may provide new perspectives on improving the decorative properties and antimicrobial properties in wood industry.

  12. Effect of Boron Quaternary Ammonium Salt on Improving Coke Thermal Property%新型含硼季铵盐对焦炭热态性能的改善研究

    Institute of Scientific and Technical Information of China (English)

    张泽志; 李龙; 王留成; 王福安

    2011-01-01

    The effect of spraying boron quaternary ammonium salt(which was as a new type deterioration inhibitor) on coke thermal property was investigated.The structure and morphology of coke were scanned for explaining boron quaternary ammonium salt's inhibition mechanism to coke by SEM.The results indicate that the coke reactivity index(CRI) is decreased by 8.69% and the coke strength after reaction(CSR) is improved by 7.94% when spraying 1.0% boron quaternary ammonium salt on coke samples.The SEM scanning results show that the coke surface pore diameter and the depth decrease,this helps to reduce CO2 to erode coke.%以含硼季铵盐(N-甲基溴代十二烷基二乙醇胺硼酸酯)作为新型焦炭劣化抑制剂,考察其对焦炭的热态性能改善影响,并对焦炭结构和形貌进行表征,初步探讨了含硼季铵盐改善焦炭热态性能的机理。结果表明:喷洒含硼季铵盐溶液后焦炭热态性能指标得到明显改善,1.0%的含硼季铵盐能使焦炭反应性CRI降低8.69%,反应后强度CSR提高7.94%,焦炭表面积、气孔直径和深度显著减小,减弱了二氧化碳对焦炭的侵蚀劣化作用,这为改善焦炭性能指标开拓了新途径。

  13. Hydration Structure of the Quaternary Ammonium Cations

    KAUST Repository

    Babiaczyk, Wojtek Iwo

    2010-11-25

    Two indicators of the hydropathicity of small solutes are introduced and tested by molecular dynamics simulations. These indicators are defined as probabilities of the orientation of water molecules\\' dipoles and hydrogen bond vectors, conditional on a generalized distance from the solute suitable for arbitrarily shaped molecules. Using conditional probabilities, it is possible to distinguish features of the distributions in close proximity of the solute. These regions contain the most significant information on the hydration structure but cannot be adequately represented by using, as is usually done, joint distance-angle probability densities. Our calculations show that using our indicators a relative hydropathicity scale for the interesting test set of the quaternary ammonium cations can be roughly determined. © 2010 American Chemical Society.

  14. Synthesis of aluminophosphate molecular sieves in quaternary ammonium salts and pentaerythritol eutectic mixture%季铵盐-季戊四醇低共熔混合物中合成磷酸铝分子筛

    Institute of Scientific and Technical Information of China (English)

    裴仁彦; 田志坚; 于海斌; 张耀日; 霍志萍

    2013-01-01

    Aluminophosphate molecular sieves were synthesized in eutectic mixtures consisted of quaternary ammonium salts and pentaerythritol.The as-synthesized products were characterized by X-ray diffraction,scanning electron microscopy,thermal gravimetric analysis and NMR spectroscopy.The results showed that A1PO4-16 and A1PO4-5 molecular sieves were synthesized in the eutectic mixture of tetraethylammonium chloride and choline chloride,while a cristobalite dense phase was formed in the eutectic mixture of tetrapropylammonium bromide and tetrabutylammonium bromide.The structuredirecting abilities of the quaternary ammonium cation was subject to its charge density.The smaller the charge density of the quanternary ammonium was,the weaker structure-directing ability it had.%在4种季铵盐和季戊四醇的低共融混合物中合成了磷酸铝分子筛,并通过X射线衍射、扫描电子显微镜、热重分析以及核磁共振技术进行表征.结果表明,在氯化胆碱和四乙基氯化铵的低共熔混合物中分别合成了ALPO4-16和AlPO4-5分子筛,而在四丙基溴化铵和四丁基溴化铵低共熔混合物中仅得到方石英致密相.表明在实验条件下,季铵盐阳离子的电荷密度影响结构导向能 力,电荷密度越小,结构导向能力越弱.

  15. 硅藻土负载壳聚糖季铵盐处理甲基橙染料废水%Study on Methyl Orange Waste Water Treatment through Diatomite Loading Quaternary Ammonium Salt of Chitosan

    Institute of Scientific and Technical Information of China (English)

    李小芳; 冯小强; 杨声

    2012-01-01

    利用硅藻土负载壳聚糖季铵盐处理甲基橙染料废水,考察了季铵盐取代度、添加量、温度、甲基橙初始浓度、pH值和作用时间对甲基橙脱色率的影响.结果表明,壳聚糖季铵盐的季铵化取代度为55.6%时,硅藻土/HACC2对甲基橙的脱色效果最好.当pH值为2.6,20℃下搅拌90 min,硅藻土负载壳聚糖季铵盐添加量为350 mg时,对50 mL质量浓度为0.05 mg/mL的甲基橙染料去除率达95.3%.%This paper examined the adsorption of diatomite loading quaternary ammonium salt of chitosan treating methyl orange, from the aspects of degree of substitution, adsorbent dosage, temperature, initial concentration of methyl orange, pH value and mixing time. The results showed that D/HACC2 had the best decolonization effect towards methyl orange, while the substitution degree of chitosan quaternary ammonium salt was 55.6%. The decolorization rate of methyl orange in 50 mL is 95.3 %, when the pH value is 2.6, stirring time is 90 min, adsorbent dosage is 350 mg and the initial concentration of methyl orange is 0.05 mg/mL.

  16. EVALUATION OF THE ANTIMICROBIAL EFFECTS OF NEW HETEROCYCLIC BIS-QUATERNARY AMMONIUM COMPOUNDS ON BIOFILMS

    Directory of Open Access Journals (Sweden)

    OANA E. CONSTANTIN

    2016-07-01

    Full Text Available Considering the well-known mechanism of adaptable resistance of microorganisms to chemical compounds through biofilms formation and the widespread use of N-heterocyclic quaternary ammonium salts (QAC as disinfectants, in this study we have evaluate the effect of 8 newly synthesized symmetrical and unsymmetrical diquaternary ammonium salts of 1,2-bis-(4-pyridil-ethane on bacterial biofilms produced by three different bacterial strains. The effect of the exposure to quaternary ammonium salts on biofilm communities was investigated within biofilms obtained in a conventional testing system, on stainless steel and glass surfaces. Differential plate counts were used to characterize the developed communities and the effects of QAC exposure and the results were correlated with epifluorescence microphotographs. The data obtained revealed a significant reduction of bacterial cells in the biofilms tested with 4-7 log CFU for all the QAC.

  17. ANTIBACTERIAL ACTIVITY OF SINGLE AND MIXED AMMONIUM AND PHOSPHONIUM SALTS GRAFTED ON “GEL—TYPE” SYYRENE—DIVINYLBENZENE COPOLYMERS

    Institute of Scientific and Technical Information of China (English)

    AdrianaPOPA; Corneliu-MircesaDAVIDESCU; 等

    2000-01-01

    A systematic study on the synthesis and antibacterial activity of the quaternary"onium" salts grafted on an insoluble"gel-type" stryene-7% divinylbenzene copolymer by polymer-analogous reactions is showed.Antibacterial activity of quaternary ammonium and/or phosphonium salts grafted on polymer-supports has been studied against staphylococcus aureus and Escherichia coli.A wide variety of "onium" salts bound to macromolecular supports with different quaternary groups and different quaternary chain length substituents were examined.The antibacterial activity of mixed "onium" salts increases as a consequence of the association of ammonium and phosphonium salts grafted on the same polymeric support.

  18. ARE QUATERNARY AMMONIUM ANTIBACTERIALS SUITABLE FOR DENTAL COMPOSITE RESINS?

    Directory of Open Access Journals (Sweden)

    Iman MOHAMMADZADEH

    2016-06-01

    Full Text Available The objective of this study was to answer the following question: are quaternary ammonium antibacterials suitable for dental materials? Reviewing the literature on quaternary ammonium compounds evidenced that this type of compounds is soluble in water. Our own findings also showed that they are well soluble in water and that their application as dental composites requires to check their solubility level in water.

  19. Efeito de sais quaternários de amônio na organofilização de uma argila bentonita nacional Effect of quaternary ammonium salts on the organophilization of national bentonite clay

    Directory of Open Access Journals (Sweden)

    R. Barbosa

    2006-12-01

    Full Text Available A bentonita, composta predominantemente pelo argilomineral montmorilonita que lhe confere as propriedades físicas concentra a maior parte das reservas nacionais (62% no Estado da Paraíba. A transformação da bentonita em argila organofílica consiste em um procedimento laboratorial simples e pode ser realizada através de reação de troca dos cátions (Na+ ou Ca2+ presentes na superfície e no espaço interlamelar dos argilominerais, por cátions de sais quaternários de amônio. Neste trabalho as bentonitas organofílicas foram preparadas utilizando quatro tipos diferentes de sais quaternários de amônio, tais como: cloreto de alquil dimetil benzil amônio (Dodigen, cloreto de estearil dimetil amônio (Praepagen, cloreto de cetil trimetil amônio (Genamin e brometo de cetil trimetil amônio (Cetremide. As argilas organofilizadas foram caracterizadas por termogravimetria, difração de raios X, análise química e por fluorescência de raios X. Os resultados confirmaram a incorporação dos sais quaternários de amônio na estrutura da argila e mostraram que dois dos quatro sais quaternários utilizados, o Praepagen e o Cetremide apresentaram uma faixa maior de estabilidade térmica.Bentonite clay, mainly composed by montmorillonite that provides the physical properties, concentrates the majority of the national reserve (62% in the Paraíba State. The transformation of bentonite clay to organoclay is made with a simple laboratory procedure and this modification can be obtained by cation (Na+ or Ca2+ exchange reaction that are present on the surface and in the interlayer space of the mineral clays by quaternary ammonium salts. In this, the organoclays bentonite were preparedwith four different types of quaternary ammonium salts such as alkyldimethylbenzylammonium chloride (Dodigen, esthearildimethylammonium chloride (Praepagen, cethyltrimethylammonium chloride (Genamin and cethyltrimethylammonium bromide (Cetremide. The organoclays were

  20. 四苯硼钠-季胺盐法测定KCl中K+含量的研究%K+ Measurement in KCl by Sodium Tetraphenylborate- Quaternary Ammonium Salt Method

    Institute of Scientific and Technical Information of China (English)

    姜旭敏; 李凤英; 史忠录

    2012-01-01

    文章介绍了用四苯硼钠-季胺盐法测定氯化钾中钾离子含量的方法,测定的试样数据与GB6549 - 1996《氯化钾》中规定的四苯硼钾重量法的数据采用方差分析,得出两方法间无显著性差异,采用该方法测定结果准确,测定速度快,适用于青海格尔木察尔汗盐湖氯化钾生产企业化工分析的需要.%Method of K + measurement in KC1 by sodium tetraphenylborate - quaternary ammonium salt method is introduced in the article. The measure data are compared with the data which are measured by sodium tetraphenylborate gravimetric method according to GB 6549-1996 《potassium chloride》by variance analysis. It is hardly diferent between them. The measure data are accurate and the measure speed is rapid. It can meet the requirement to measure K + in KCl lor the potassium chloride production enterprise in Chaerhan Salt Lake Area in Golmud of Qinghai.

  1. 壳聚糖季铵盐包裹甲状旁腺激素相关肽制备纳米缓释颗粒%Quaternary ammonium salt chitosan nanoparticles encapsulate parathyroid hormone-related peptide nanoparticles

    Institute of Scientific and Technical Information of China (English)

    罗菊英; 郭卫春; 赵胜豪; 赵正据; 唐谨; 余铃

    2011-01-01

    BACKGROUND: Small-scale studies have shown that low-dose, intermittent application of parathyroid hormone related peptide can effectively treat osteoporosis in postmenopausal women. But it is disadvantageous due to prone to degrade, short half-life and expensive cost, therefore it is necessary to modulate the release speed of parathyroid hormone related peptide using controlled-release system and to improve the biological efficiency.OBJECTIVE: To prepare a novel nanoparticles for carrying drugs, and to investigate encapsulation efficiency and in vitro release characteristics of parathyroid hormone-related peptide.METHODS: Quaternary ammonium salt of chitosan nanoparticles were prepared based on ionic gelation, and the characteristics were observed by fourier transform infrared spectroscopy and transmission electron microscopy, and the encapsulation efficiency and release characteristics in vitro of the nanoparticles were determined.RESULTS AND CONCLUSION: Chitosan quaternary ammonium salt and sodium tripolyphosphate were mixed to form the nanoparticles when the quantity of chitosan quaternary ammonium salt and sodium tripolyphosphate was 5:1-2:1 under stirring at room temperature. The nanoparticles size was about 100-180 nm, regular sphere. With the increase of the parathyroid hormone-related peptide concentration, the drug encapsulation efficiency increased but the loading capacity reduced. The drug-loading nanoparticles showed slow release characteristics in PBS solution in vitro.%背景:小范围研究显示,低剂量、间歇性应用甲状旁腺激素相关肽能有效治疗绝经后妇女骨质疏松症.但其存在着易变性、半衰期短、价格昂贵等缺陷,因此研制应用缓释系统控制甲状旁腺激素相关肽的释放速度,提高其生物利用效率极为必要.目的:制备一种新型纳米载药颗粒,探讨其对甲状旁腺激素相关肽的包封及体外释放特性.方法:采用离子交联法制备壳聚糖季

  2. 醚-酯型季铵盐阳离子表面活性剂的合成及性能%SYNTHESIS AND PROPERTIES OF ETHER-ESTER TYPE QUATERNARY AMMONIUM SALT CATIONIC SURFACTANTS

    Institute of Scientific and Technical Information of China (English)

    孟小华

    2013-01-01

    以硬脂醇、金属钠及3-氯-2-羟基丙基三甲基氯化铵为原料合成了3-烷氧基-2-羟基丙基三甲基氯化铵(OPAC),进一步与硬脂酰氯反应后得到醚-酯型双长链季铵盐阳离子表面活性剂3-烷氧基-2-酰氧基丙基三甲基氯化铵.正交实验确定的最佳合成条件为:1,4-二氧六环为溶剂,用量40 mL,n(OPAC)∶n(硬脂酰氯)∶n(吡啶)=1∶1∶1,回流加热反应5h,收率为93.0%.产物结构通过红外及核磁共振氢谱表征.产物表面活性较高,具备良好的织物柔软性及酸碱稳定性.%3-Alkoxy-2-hydroxypropyl trimethyl ammonium chloride (OPAC) was synthesized by stearyl alcohol,metal sodium and 3-chloro-2-hydroxypropyl trimethyl ammonium chloride.Double long chain ether-ester quaternary ammonium salt cationic surfactants 3-alkoxy-2-acyloxy trimethyl ammonium chloride was further synthesized with OPAC and stearyl chloride.Through orthogonally arranged experiments,the optimal esterification conditions were obtained as follows:40 mL 1,4-dioxane was used as solvent,n(OPAC) ∶ n(stearyl chloride) ∶ n(pyridine)=l ∶ 1 ∶ 1 and refluxing time was 5 h.The yield of end product was 93.0%.The structure was confirmed by IR and 1H NMR.Performance results show that the product has high surface activity,good fabric softness and pH stability.

  3. Antibacterial activity of reactive quaternary ammonium compounds in solution and in nonleachable coatings

    NARCIS (Netherlands)

    Gozzelino, G.; Romero Tobar, D.E.; Chaitiemwong, N.; Hazeleger, W.C.; Beumer, R.R.

    2011-01-01

    Antibacterial polymers suitable for coating applications without leaching of the biocidal component have been obtained by UV copolymerization of acrylic resins with acrylic monomers containing quaternary ammonium moieties. Suitable reactive biocides, based on quaternary ammonium monomers (QAMs), end

  4. Studies on the Extraction of Gold (Ⅰ) Cyanide by Quaternary Ammonium Salt Using 198Au as Tracer%用198Au示踪法研究季铵盐体系萃取金

    Institute of Scientific and Technical Information of China (English)

    张天喜; 周维金; 高宏成; 陈景; 吴瑾光

    2002-01-01

    The solvent extraction of KAu(CN)2 from alkaline solution by quaternary ammonium salts (trialkylmethylammonium chloride or cetyltrimethylammonium bromide) was investigated by means of 198Au radioactive tracer method. Various parameters, such as the gold (Ⅰ) concentration in aqueous phase, the modifier, emulsification at the interface of two phases, and phase ratio used in the extraction of gold (Ⅰ) were studied. The results demonstrate that almost all gold (Ⅰ) in the aqueous phase was practically extracted into the organic phase. The water content in the organic phase decreased significantly with increase of gold (Ⅰ) concentration using long chain alcohol as modifier, in contrast with the system with tributyl phosphate (TBP) as modifier. Emulsification at the interface of two phases decreases with an increase of modifier concentration in the organic phase or with the addition of a small amount of lysozyme into the aqueous phase. The method with 198Au tracer can be directly used to determine the Au(Ⅰ) concentration both in aqueous and organic phases, which is especially suitable for the low concentration of Au(Ⅰ).

  5. PREPARATION AND PHOTOSENSITIVITY OF WATER SOLUBLE PHENOLIC RESINS CONTAINING ACRYLOYL AND QUATERNARY AMMONIUM CHLORIDE GROUPS

    Institute of Scientific and Technical Information of China (English)

    Xiao-ming Tan; Hong-quan Xie; Nai-yu Huang

    2002-01-01

    New water soluble and photocrosslinkable prepolymers containing acrylate and quaternary ammonium salt groups were synthesized from epoxy phenolic resin via ring-opening reaction with acrylic acid and with aqueous solution of triethylamine hydrochloride successively. The second reaction needs no phase transfer catalyst to accelerate, since the product formed can act as a phase transfer catalyst. The prepolymer obtained contains both photocrosslinkable acrylate groups and hydrophilic quaternary ammonium salt groups. Optimum conditions for these reactions were studied. The photosensitivity of the prepolymer was also investigated. The effects of different photoinitiators, different crosslinkable diluent monomers and amine accelerator on the photosensitivity of the prepolymer were compared. The photoinitiator of hydrogen abstraction type is still effective without using amine or alcohol as accelerator, because the prepolymer contains α H beside the OH groups formed in the ring-opening reactions.

  6. 含氟季铵盐表面活性剂的合成与应用研究进展%Research progress of synthesis and application of fluorinated quaternary ammonium salt surfactants

    Institute of Scientific and Technical Information of China (English)

    徐运欢; 郑成; 林璟; 毛桃嫣; 黄武欢

    2013-01-01

      Fluorinated quaternary ammonium salts are novel surfactants, which exhibit some unusual physico-chemical properties, such as high surface activity, high thermally chemical stability, hydro-oleophobicity. The synthesis methods of cationic fluorinated surfactants are reviewed and categorized according to the characteristics of different molecular structures. Especially the surfactants with some specific functions, such as diallyl, hydroxyl, gemini and amino groups, are presented. Their applications in phase transfer catalyst, supercritical carbon dioxide additive, metal corrosion inhibitor, foam extinguishing agent, textile finishing agent, and antibacterial agent are discussed. The current problems and developing trends of fluorinated quaternary ammonium surfactants are analyzed and prospected.%  含氟季铵盐表面活性剂是一类具有高表面活性、高耐热稳定性、高化学稳定性和憎水、憎油等特殊性能的新型表面活性剂。本文系统综述了含氟季铵盐表面活性剂的合成路线和方法,并按照其不同的分子结构特点进行了分类比较,着重介绍了含二烯丙基、羟基、双子、胺基等一些特定功能基团的含氟季铵盐表面活性剂的合成和特性,并阐述了其在相转移催化剂、超临界 CO2助剂、金属腐蚀抑制剂、泡沫灭火剂、织物整理剂、抗菌剂等方面的应用。最后,分析了含氟季铵盐表面活性剂目前存在的问题及对其发展趋势进行了展望。

  7. Preparation and antibacterial activity of quaternary ammonium salt monomers%牙科季铵盐类单体的制备及其抗菌作用的研究

    Institute of Scientific and Technical Information of China (English)

    肖玉鸿; 陈吉华; 方明; 邢晓东; 李芳; 柴治国

    2008-01-01

    目的 制备3种季铵盐类单体,比较其对口腔常见细菌的作用,为牙科抗菌材料的研制提供基础依据.方法 制备3种季铵盐类单体[甲基丙烯酰氧乙基-苄基-二甲基氯化铵(methacryloxylethyl benzyl dimethyl ammonium chloride,DMAE-BC)、甲基丙烯酰氧乙基-间氯苄基-二甲基氯化铵(methacryloxylethyl m-chloro benzyl dimethyl ammonium chloride,DMAE-m-CBC)、甲基丙烯酰氧乙基-正十六烷基-二甲基氯化铵(methacryloxylethyl cetyl dimethyl ammonium chloride,DMAE-CB)],采用液体稀释法比较其对变形链球菌、血链球菌、牙龈卟啉单胞菌、产黑普氏菌的抗菌作用.结果 3种季铵盐类单体中DMAE-CB的抗菌效果最强,对4种口腔细菌的最低抑菌浓度值为1.2至4.8 mg/L,而另外两种单体对4种细菌的最低抑菌浓度值为1562.5至3125.0 ms/L.结论 3种季铵盐类单体对变形链球菌、血链球菌、牙龈卟啉单胞菌、产黑普氏菌均有不同程度的抗菌作用,其中DMAE-CB的抗菌活性最强.%Objective To prepare three quaternary ammonium salt (QAS) monomers, and to compare their antibacterial activities against four oral bacterial strains. Methods Three antibacterial monomers [ methacryloxylethyl benzyl dimethyl ammonium chloride(DMAE-BC) , methacryloxylethyl m-chloro benzyl dimethyl ammonium chloride( DMAE-m-CBC ), methacryloxylethyl cetyl dimethyl ammonium chloride (DMAE-CB) ] were synthesized according to the general structure of target monomers. Their antibacterial effects were investigated using the broth dilution test on Gram-positive and Gram-negative bacterial strains ( Streptococcus mutans ,Streptococcus sanguis, Porphyromonas gingivalis, Prevotella melaninogenica). Results Three different monomers were successfully obtained. All the tested bacterial strains were susceptible to the three monomers, among which DMAE-CB exhibited the lowest minimal inhibitory concentrations (MIC) ranging from 1.2 to 4. 8 mg/L Conclusions All these three

  8. 新型腰果基季铵盐表面活性剂的合成及表面性能研究%Synthesis and Surface Properties of New Type Cashew Quaternary Ammonium Salt Surfactant

    Institute of Scientific and Technical Information of China (English)

    沈国鹏; 刘九竹; 吴鸣建; 黄强

    2013-01-01

    A new type of cardanol based quaternary ammonium salt surfactant,i.e.3-cardanol-oxy-2-hydroxy) propyl-N,N,N-trimethyl ammonium chloride as raw materials,was synthesized with a yield of about 72% by using cashew phenol and glycidyl trimethyl ammonium chloride(GTA) which was a kind of active intermediate.The aimed product' s superficial characteristics was identified with high performance liquid chromatography,infrared spectroscopy and high resolution mass spectrometry.The cationic group was found in the product through bromophenol blue inspection.It showed good foaming capacity and foam stability through foam performance measurement.The surface activities of the product were preliminarily measured.The results showed that the critical micelle concentration (CMC) of the products was 6.38 mmol/L,surface tension at CMC (γCMC) was 38.86 mN/m.The new products shows excellent emulsifying ability.%以活性中间体缩水甘油基三甲基氯化铵(GTA)和腰果酚为原料,制备了新型腰果基季铵盐表面活性剂——(3-腰果酚氧基-2-羟基)丙基-N,N,N-三甲基氯化铵,产物收率约为72%,采用高效液相色谱、红外光谱和高分辨质谱对产物进行了表征,溴酚蓝检验证实产品含有阳离子基团,泡沫性能测定显示产品具有良好的起泡及稳泡能力.同时初步测试了其表面活性,结果表明,25℃下,产品的临界胶束浓度(CMC)为6.38 mmol/L,临界胶束浓度下的表面张力(γCMC)为38.86 mN/m,新型腰果基季铵盐还具有良好的乳化作用.

  9. 新型含氟季铵盐表面活性剂的合成与表面性能%Synthesis and surface properties of a novel perfluoroalkyl-containing quaternary ammonium salt

    Institute of Scientific and Technical Information of China (English)

    徐运欢; 郑成; 林璟; 毛桃嫣; 黄武欢; 甘茵

    2014-01-01

    A novel perfluoroalkyl-containing quaternary ammonium salt was synthesized from N-methyl diethanolamine (MDEA) and perfluorinated hexyl ethyl iodide. The effects of solvent, reaction temperature,reactant molar ratio,solvent volume and reaction time on reaction on conversion rate were studied. The optimal process parameters for synthesizing product were obtained by orthogonal experiment,which are 8 mL n-butyl alcohol,90℃ reaction temperature,42 h reaction time,2.5∶1 molar ratio of perfluorinated hexyl ethyl iodide and MDEA. The conversion rate of MDEA was 93.75%. The structure of product was characterized by Fourier transform infrared spectroscopy,mass spectrometry and nuclear magnetic resonance spectrum. The surface properties of the surfactant were studied by measuring the surface tension of the product aqueous solution. The results showed that the critical micellar concentration (CMC) of the above perfluoroalkyl-containing quaternary ammonium salt was 1.518 mmol/L,theγCMC was 9.3 mN/m. The single molecule saturated adsorption,single molecule average areas on the saturated adsorption layer,and the micellization standard free energy were 0.354×10-10 mol/cm2,4.69 nm2,and-26.03 kJ/mol,respectively. Compared with similar products,the product exhibited excellent surface properties.%以N-甲基二乙醇胺(MDEA)和全氟己基乙基碘为主要原料,合成了一种新型的含氟季铵盐表面活性剂。通过单因素和正交实验,考察了溶剂、反应温度、反应物摩尔比、溶剂体积和反应时间对MDEA转化率的影响,探讨优化出最佳工艺条件:溶剂为正丁醇,反应温度90℃,n(全氟己基乙基碘)∶n(MDEA)=2.5∶1,溶剂体积为8 mL,反应时间为42 h,转化率达到93.75%。通过傅里叶红外吸收光谱、质谱和核磁共振谱对目标产物进行表征,并通过测定其水溶液的表面张力研究了产物的表面活性。其临界胶束浓度(CMC)为1.518 mmol/L,临界胶束浓

  10. 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.

  11. Enhancement of the luminescence efficiency of europium(III) tris(β-diketonato) complex in organic media by quaternary ammonium salts with anionic ligands.

    Science.gov (United States)

    Katano, Hajime; Uematsu, Kohei; Tsukatani, Toshihide

    2011-01-01

    Benzyldimethyltetradecylammonium (BA14(+)) salts with anionic ligands (X(-)), such as bis(2-ethylhexyl)sulfosuccinate, bis(2-ethylhexyl)phosphate (BEHP(-)), and benzotriazole (BTA(-)) anions, were prepared. These salts were soluble in various organic solvents. The luminescence emission spectra of organic solutions of a red luminescent, tris(1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-4,6-octadionato)europium(III) complex in the presence of the BA14X's were recorded. The emission intensity of the Eu(III) complex was increased remarkably by the addition of BA14X (X(-) = BEHP(-) and BTA(-)). This effect can be attributed to the formation of 1:1 X(-)-adducts of the Eu(III) complex, in which the asymmetry of the ligand field is increased so as to enhance the emission efficiency of the (5)D(0)→(5)F(2) transition. The enhancement effect by BA14X was higher than that of charge-neutral ligands, such as tri-n-octylphosphine oxide and 1,10-phenanthroline, which have been used as second ligands to enhance the emission efficiency of tris(β-diketonato)europium(III) complexes.

  12. Quaternary ammonium room-temperature ionic liquid including an oxygen atom in side chain/lithium salt binary electrolytes: ab initio molecular orbital calculations of interactions between ions.

    Science.gov (United States)

    Tsuzuki, Seiji; Hayamizu, Kikuko; Seki, Shiro; Ohno, Yasutaka; Kobayashi, Yo; Miyashiro, Hajime

    2008-08-14

    Interactions of the lithium bis(trifluoromethylsulfonyl)amide (LiTFSA) complex with N, N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium (DEME), 1-ethyl-3-methylimidazolium (EMIM) cations, neutral diethylether (DEE), and the DEMETFSA complex were studied by ab initio molecular orbital calculations. An interaction energy potential calculated for the DEME cation with the LiTFSA complex has a minimum when the Li atom has contact with the oxygen atom of DEME cation, while potentials for the EMIM cation with the LiTFSA complex are always repulsive. The MP2/6-311G**//HF/6-311G** level interaction energy calculated for the DEME cation with the LiTFSA complex was -18.4 kcal/mol. The interaction energy for the neutral DEE with the LiTFSA complex was larger (-21.1 kcal/mol). The interaction energy for the DEMETFSA complex with LiTFSA complex is greater (-23.2 kcal/mol). The electrostatic and induction interactions are the major source of the attraction in the two systems. The substantial attraction between the DEME cation and the LiTFSA complex suggests that the interaction between the Li cation and the oxygen atom of DEME cation plays important roles in determining the mobility of the Li cation in DEME-based room temperature ionic liquids.

  13. 一种单方双长链季铵盐消毒剂性能的研究%STUDY ON PROPERTIES OF A LONG-DOUBLE-CHAIN QUATERNARY AMMONIUM SALT DISINFECTANT

    Institute of Scientific and Technical Information of China (English)

    王嵬; 吴晓松; 孙巍; 谈智; 陈越英; 张伟; 徐燕

    2012-01-01

    Objective To Study the disinfection properties of a long-double-chain quaternary ammonium salt composed with didecyl dimethyl ammonium chloride. Methods Physicochemical examination, disinfectant properties related examination were used to carry out in laboratory to study the properties of the disinfectant. Results The killing logarithms of Escherichia coli , Staphylococcus aureus and Pseudomonas aeruginosa in suspension exposed to the water solution containing the disinfectant 460 mg/L for 0.5 min attained higher than 5.0.The killing logarithm of Candida albicans in suspension exposed to the water solution containing the disinfectant 460 mg/L for 1 rain attained higher than 4.0. The average killing logarithms of natural bacteria on surface was 〉1.0 by the disinfection solution containing 460 mg/L for 5 minutes. Immersion in the disinfection solution containing 460 mg/L for 72 h caused essentially no corrosion of stainless steel and copper coupon, and light corrosion of aluminum coupon and carbon steel. Conclusion The disinfectant was stable, low corrosion and has good efficacy in killing vegetative forms of bacteria and yeast.%目的研究一种以二癸基二甲基氯化铵为主要成分的单方双长链季铵盐消毒剂的消毒性能。方法用理化测定方法、消毒性能相关检验方法,对该消毒剂性能进行了试验。结果该单方二癸基二甲基氯化铵消毒剂使用浓度为460mg/L,对金黄色葡萄球菌、大肠杆菌、铜绿假单胞茵作用O.5min,杀灭对数值〉5.00;对白色念珠茵作用1Omin,杀灭对数值〉4.00。该消毒剂对物体表面作用5min,对自然茵平均杀灭对数值均大于10,对不锈钢片和铜片基本无腐蚀,对铝片和碳钢片轻度腐蚀。结论该单方二癸基二甲基氯化铵消毒剂储存性能稳定,腐蚀性低,对细茵繁殖体和酵母茵杀灭效果好。

  14. Synthesis of reactive chitosan quaternary ammonium salt and antibacterial properties of modified cotton fabric%反应性壳聚糖季铵盐的合成及其改性棉织物的抗菌性能

    Institute of Scientific and Technical Information of China (English)

    张伟; 戴新兰; 周静洁; 朱刚; 徐洵; 黄颖霞; 王笃杰

    2016-01-01

    In order to improve the water- solubility of chitosan and strengthen its binding force with the cotton fiber, 2- hydroxypropyltrimethyl ammonium chloride chitosan (HTCC) was synthesized using chitosan and 2,3- epoxypropyltrimethyl ammonium chloride, then HTCC was reacted with N- (hydroxymethyl)- acryl⁃amide, and the water- soluble O- methyl acrylamide quaternary ammonium salt of chitosan (NMA- HTCC) with fiber reactive groups was synthesized. FT- IR and 1H- NMR were used to characterize the synthesized NMA- HTCC, which was then applied on the antibacterial finish of cotton fabrics. The antibacterial properties of cotton fabrics before and after treatment were tested by oscil ation flask method to explore the optimum process conditions of cotton fabric treated with NMA- HTCC. The results showed that when the concentration of NMA- HTCC was 7 g/L, the mass fraction of NaHCO3 was 2%, treated at 60 ℃ for 50 min, cured at 160 ℃for 3 min, the inhibition rate of cotton fabrics to Staphylococcus aureus and Escherichia coli were the best and stil higher than 90%after 30 times of soaping.%为了提高壳聚糖的水溶性,增强其与棉纤维的结合力,将壳聚糖与2,3-环氧丙基三甲基氯化铵反应,合成2-羟丙基三甲基氯化铵壳聚糖(HTCC),HTCC再与N-羟甲基丙烯酰胺反应,合成带有纤维反应性基团的水溶性O-甲基丙烯酰胺壳聚糖季铵盐(NMA-HTCC)。用FT-IR和1H-NMR对NMA-HTCC进行表征,并将其应用到棉织物的抗菌整理中,采用振荡烧瓶法对整理前后棉织物的抗菌性进行了测试,探索较佳整理工艺。结果表明:当NMA-HTCC质量浓度为7 g/L,NaHCO3用量为2%,处理温度为60℃,处理时间为50 min,焙烘温度为160℃,焙烘时间为3 min时,棉织物对金黄色葡萄球菌和大肠杆菌的抑菌率最好,且皂洗30次后,抑菌率仍高于90%。

  15. Synthesis of quarternary ammonium salts with dithiocarbamate moiety and their antifungal activities against Helminthosporium oryzae

    Indian Academy of Sciences (India)

    Mandeep Singh; Anita Garg; Anjali Sidhu; Vineet Kumar

    2013-05-01

    Quaternary ammonium salts containing dithiocarbamate moiety were synthesized and evaluated for their antifungal activities against Helminthosporium oryzae. All the synthesized compounds showed moderate to promising fungitoxicity against the test. Some of the synthesized compounds inflicted antifungal activity greater than the standard fungicide.

  16. 季铵盐型洗手液的制备及其抗菌性能研究%Preparation and performance of a quaternary ammonium salt based antibacterial hand sanitizer

    Institute of Scientific and Technical Information of China (English)

    黎敏珊; 郑成; 毛桃嫣; 周虹谷; 欧志荣

    2016-01-01

    By selecting and optimizing the formulation of components,a quaternary ammonium salt based antibacterial hand sanitizer was prepared. The formulation (expressed as mass fraction)consists of 0. 75%sodium ethoxylated dodecyl alcohol sulfate (AES),2. 25% tetradecylmethyldihydroxyethylammonium bromide (TMDAB),20% cocamidopropyl betaine (CAB - 35),0. 25% disodium ethoxylated alcohol succinic acid monoester sulfonate (MES),1. 5% coconut acid diethanolamide (6501),1% glycerin,0. 1% dimethylol dimethyl hydantoin (DMDMH),a little amount of fragrance and colorant,as well as a small amount of citric acid for adjusting pH value. The balance is distilled water. Test results of the product showed that the sterilization efficacy for Escherichia coli and Staphylococcus aureus achieves 99. 99% and 100% respectively. The stability and foaming performance of the product are well. Besides,its production cost is rather low. As comparing with some liquid hand cleaners from the market,the prepared product shows somewhat better antibacterial efficacy.%通过对原料的选择和配方的优化,制备了一种季铵盐型抗菌洗手液。该洗手液配方(以质量分数计)由0.75%十二烷基聚氧乙烯醚硫酸钠(AES),2.25%十四烷基甲基二羟乙基溴化铵(TMDAB),20%椰油酰胺丙基甜菜碱(CAB -35),0.25%醇醚磺基琥珀酸单酯二钠盐(MES),1.5%椰子油二乙醇酰胺(6501),1%甘油,0.1%二羟甲基海因(DMDMH),少量香精及色素,少量柠檬酸调pH和余量的蒸馏水组成。经过测试表明该洗手液对大肠杆菌和金黄色葡萄球菌的杀菌率达到99.99%和100%,产品稳定性、起泡性好,生产成本较低,与市售的某些抗菌洗手液相比,该洗手液显示出一定的优越性。

  17. Quaternary ammonium biocides as antimicrobial agents protecting historical wood and brick.

    Science.gov (United States)

    Rajkowska, Katarzyna; Koziróg, Anna; Otlewska, Anna; Piotrowska, Małgorzata; Nowicka-Krawczyk, Paulina; Brycki, Bogumił; Kunicka-Styczyńska, Alina; Gutarowska, Beata

    2016-01-01

    Quaternary ammonium compounds (QACs) are widely used in disinfection of water, surfaces and instruments as well as in textile, leather and food industries because of their relatively low toxicity, broad antimicrobial spectrum, non-volatility and chemical stability. Due to these advantages, QACs are also used in restoration and can be applied on historical material. The aim of this study was to determine the usefulness of biocides based on quaternary ammonium salts and containing various excipients in the protection of historical materials against microbial growth. The study determined the antimicrobial activity of three biocides against bacteria: Pseudomonas fluorescens, Staphylococcus equorum, Bacillus cereus, Bacillus muralis, Sporosarcina aquimarina and Rhodococcus fascians, and moulds: Chaetomium globosum, Penicillium citreonigrum, Cladosporium cladosporioides I, Acremonium strictum, Aspergillus fumigatus and Cladosporium cladosporioides II, all isolated from historical wood and brick. Staphylococcus equorum, Bacillus cereus, Sporosarcina aquimarina and Rhodococcus fascians bacteria, and Cladosporium cladosporioides I and Acremonium strictum moulds showed high sensitivity to quaternary ammonium biocides. Historical wood can be effectively disinfected by three applications of biocide A (30% v/v) containing dodecyl dimethyl ammonium chloride (DDAC), citric acid, propiconazole and propanol. Disinfection of historical brick can be carried out by three applications of 6% v/v solutions of biocide B (based on DDAC and ethylenediaminetetraacetic acid - EDTA) or biocide C (containing a non-ionic surfactant, DDAC and EDTA). Effective protection of historical building materials against microbial growth for a period of seven days can be achieved by the application of biocide A (30% v/v) on the wood surface and biocide B (6% v/v) on the brick surface.

  18. 40 CFR 721.10154 - Quaternary ammonium compounds, dicoco alkyldimethyl, chlorides, reaction products with silica.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Quaternary ammonium compounds, dicoco alkyldimethyl, chlorides, reaction products with silica. 721.10154 Section 721.10154 Protection of Environment... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10154 Quaternary ammonium...

  19. 氟哌啶醇季铵盐衍生物对冠状动脉作用的研究%Effect of Quaternary Ammonium Salt Derivation of Haloperidol on Coronary Artery

    Institute of Scientific and Technical Information of China (English)

    石刚刚; 郑锦鸿; 李长潮; 陈锦香; 庄学煊; 陈少刚; 刘幸平

    2000-01-01

    Objective: To observe the effect of quaternary ammonium salt derivation of haloperidol on coronary artery. Method: By using the model of adverse reaction of extrapyramidal system induced by haloperidol ip on mice, to observe the behavior effect of its derivation(F3)on same dose and administration. Using the bioassay of porcine coronary artery strips, F3(10-6, 10-5 and 10-4moL/L)were added into the bath medium prior to KCl(10~40mmoL/L)administration to observe the effect of F3 on dose-response curve of contraction induced by KCl, and the block action of F3(10-4moL/L)on the contraction induced by KCl respectively; Using the Langendorff perfusion, to observe the effect of F3(10-6 , 5×10-6, 10-5moL/L)on reduction of coronary artery flow of guinea-pig induced by pituitrin. Results: Haloperidol induced Parkinsons like syndrome, but F3 could not induce the same effect. F3 decreased coronary artery strips contraction curve induced by KCl in dose-dependent manner. F3 also blocked the contraction induced by KCl. F3 antagonized the reduction of coronary flow induced by pituitrin on isolated heart of guinea-pig in dose-dependent manner. Conclusion: F3 caused coronary artery dilation as haloperidol , and did not cause any adverse reaction of extrapyramidal system as it.%目的:观察氟哌啶醇季铵盐衍生物对冠状动脉的作用.方法:利用氟哌啶醇所致小鼠锥体外系不良反应模型,观察其衍生物(F3)的作用;利用猪冠状动脉条生物鉴定,观察F3(10-6,10-5 and 10-4moL/L)对KCl(10~40mmoL/L)诱导的冠脉条收缩的拮抗作用,阻断由KCl(40mmoL/L)诱导的冠脉条的收缩;利用豚鼠离体心脏灌流,观察F3(10-6, 5×10-6, 10-5moL/L)拮抗脑垂体后叶素所致冠脉流量减少的作用.结果:氟哌啶醇可致小鼠产生类帕金森氏综合征,而在F3各剂量组中没有出现同样的作用.F3量效依赖地拮抗由KCl所致的冠脉条收缩,并阻断较大剂量KCl所致的冠脉条的痉挛.F3 可以量效依赖

  20. 啶虫脒--木质素季铵盐--膨润土缓释剂的制备及性能%Preparation and performance of acetaniprid-lignin quaternary ammonium salt-bentonite slow release formulation

    Institute of Scientific and Technical Information of China (English)

    田金玲; 任世学; 方桂珍

    2015-01-01

    为了提高木质素产品的附加值,以木质素季铵盐为改性剂、钠基膨润土为原料,制备了不同季铵盐载量的膨润土。通过FTIR表征改性膨润土结构,并采用XRD分析其底面间距。以啶虫脒为药物释放的对象、改性膨润土作为释放的主要载体,利用浸渍吸附的方法制备出了啶虫脒缓释剂,并研究其缓释性能。结果表明:啶虫脒在改性膨润土上的吸附量随着木质素季铵盐载量的增加而先增大后减少。当木质素季铵盐载量相当于膨润土阳离子交换容量(CEC)的0.8倍时制备的改性膨润土(L-0.8Bt)对啶虫脒的吸附效果最佳,最大吸附量为315 mg/g。制备啶虫脒缓释剂的最佳工艺条件为L-0.8Bt用量0.02 g、吸附时间4 h、啶虫脒质量浓度500 mg/L、pH值6。药水比例和温度对载药L-0.8Bt的缓释快慢有一定影响。%In order to increase the added value of lignin products, bentonites with different loading dosages of lignin quaternary ammonium salt ( LQAS ) were synthesized with sodium-based bentonite as the raw material and LQAS as the modification agent. The morphological structure of bentonite was modified by FTIR, and the basal spacing of modified bentonite was analyzed with XRD. Acetaniprid was selected as the research object for release, and the modified bentonite as main carrier for the release. Acetaniprid slow-release formulation was prepared by means of leaching and adsorption, and its performance was studied. The results showed that with the increase of LQAS dosage, the adsorption capacity of acetaniprid in modified bentonite first increased and then decreased. The adsorption effect of modified bentonite ( L-0. 8Bt) was optimum with the maximum adsorption capacity of 315 mg/g when L-0. 8Bt prepared with dosage of LQAS was 0. 8 times cation exchange capacity ( CEC) in bentonite. The optimal preparation conditions for the acetaniprid slow-release formulation were:L-0. 8Bt dosage 0. 02 g

  1. Antibacterial effect of composite resins containing quaternary ammonium polyethyleneimine nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Yudovin-Farber, Ira [Hebrew University of Jerusalem, Department of Medicinal Chemistry and Natural Products, School of Pharmacy, Faculty of Medicine (Israel); Beyth, Nurit; Weiss, Ervin I. [Hebrew University of Jerusalem, Department of Prosthodontics, Faculty of Dentistry (Israel); Domb, Abraham J., E-mail: avid@ekmd.huji.ac.i [Hebrew University of Jerusalem, Department of Medicinal Chemistry and Natural Products, School of Pharmacy, Faculty of Medicine (Israel)

    2010-02-15

    Quaternary ammonium polyethyleneimine (QA-PEI)-based nanoparticles were synthesized by crosslinking with dibromopentane followed by N-alkylation with various alkyl halides and further N-methylation with methyl iodide. Insoluble pyridinium-type particles were prepared by suspension polymerization of 4-vinyl pyridine followed by N-alkylation with alkyl halides. Polyamine-based nanoparticles embedded in restorative composite resin at 1% w/w were tested for antibacterial activity against Streptococcus mutans using direct contact test. Activity analysis revealed that the alkyl chain length of the QA-PEI nanoparticles plays a significant role in antibacterial activity of the reagent. The most potent compound was octyl-alkylated QA-PEI embedded in restorative composite resin at 1% w/w that totally inhibited S. mutans growth in 3-month-aged samples. This data indicates that restorative composite resin with antibacterial properties can be produced by the incorporation of QA-PEI nanoparticles.

  2. Antibacterial effect of composite resins containing quaternary ammonium polyethyleneimine nanoparticles

    Science.gov (United States)

    Yudovin-Farber, Ira; Beyth, Nurit; Weiss, Ervin I.; Domb, Abraham J.

    2010-02-01

    Quaternary ammonium polyethyleneimine (QA-PEI)-based nanoparticles were synthesized by crosslinking with dibromopentane followed by N-alkylation with various alkyl halides and further N-methylation with methyl iodide. Insoluble pyridinium-type particles were prepared by suspension polymerization of 4-vinyl pyridine followed by N-alkylation with alkyl halides. Polyamine-based nanoparticles embedded in restorative composite resin at 1% w/w were tested for antibacterial activity against Streptococcus mutans using direct contact test. Activity analysis revealed that the alkyl chain length of the QA-PEI nanoparticles plays a significant role in antibacterial activity of the reagent. The most potent compound was octyl-alkylated QA-PEI embedded in restorative composite resin at 1% w/w that totally inhibited S. mutans growth in 3-month-aged samples. This data indicates that restorative composite resin with antibacterial properties can be produced by the incorporation of QA-PEI nanoparticles.

  3. Synthesis and Antibacterial Property of Heteropoly Acid Quaternary Ammonium Salt Antimicrobial Agent with Double Active Center%杂多酸季铵盐双活性中心抗菌剂的合成及抑菌性能研究

    Institute of Scientific and Technical Information of China (English)

    杨万丽; 王丽艳; 王清文

    2013-01-01

    Phosphomolybdic heteropolyacid salt with Keggin structure with transition elements V, Fe, Co and Ni as substituted atom were synthesized by the stereoselective synthesis method. Four new Keggin type complexes with polyoxoanions and quaternary ammonium cation were obtained from phosphormolybdic heteropolyacid salt and dodecyltrimethylammonium bromide under hydrothermal condition. The structures of all the polyoxoanions and organic composite were characterized by the infrared (FT-IR) spectra, the ultraviolet visible (UV-Visible) spectra, thermogravimetry (TG), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM). The antibacterial activities of composite were tested for staphylococcus aureus, bacillus subtilis and escherichia coli by the inhibition zone method. The results indicated that the complexes have higher decomposition temperature than quaternary ammonium salt with 200℃ increment. The antibacterial activities of complexes is 2~3 times of quaternary ammonium salt.%本文采取立体选择法合成以过渡元素V、Fe、Co和Ni为取代原子的Keggin结构的取代型磷钼杂多酸盐,在水热条件下与十二烷基三甲基溴化铵进行化合,得到了4种新的基于Keggin型多酸阴离子和季铵阳离子的复合物.通过红外(FT-IR)、紫外(UV-Visible)、热重(TG)、X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)等手段进行了结构表征,并采用抑菌圈法对金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌进行了抑菌活性研究.结果表明,所合成的复合物的分解温度较季铵盐提高了200℃;复合物的抑菌效果是季铵盐的2~3倍.

  4. Avaliação da estabilidade térmica de sais quaternários de amônio para uso em argilas organofílicas nacionais: Parte I Evaluation of thermal stability of quaternary ammonium salts for use in national organoclays: Part I

    Directory of Open Access Journals (Sweden)

    R. Barbosa

    2010-12-01

    Full Text Available A grande propagação da nanotecnologia nos tempos atuais requer estudos cada vez mais específicos para entender a evolução desses materiais. A obtenção de boas propriedades em nanocompósitos polímero/argila faz com que estudos mais aprofundados sejam realizados sobre a estabilidade térmica dos surfactantes nas temperaturas de processamento destes materiais. Neste trabalho, a estabilidade térmica de quatro sais quaternários de amônio, tais como brometo de hexadeciltrimetil amônio, cloreto de alquildimetilbenzil amônio, cloreto de estearildimetil amônio e cloreto de hexadeciltrimetil amônio foi avaliada, visando sua posterior intercalação em argilas bentoníticas nacionais, com o propósito de torná-las organofílicas para uso em nanocompósitos poliméricos. Os sais foram caracterizados termicamente por calorimetria exploratória diferencial e termogravimetria sob Ar e N2. Os resultados indicaram que os sais à base do ânion cloreto se degradaram em temperaturas similares e o sal à base do ânion brometo se degradou em temperatura superior. Além disso, este estudo indicou que o sal cloreto de estearildimetil amônio provavelmente terá sucesso na utilização como surfactante para o uso em nanocompósitos.The large propagation of nanotechnology in modern times requires more studies to meet their specific development. For obtaining good properties of polymer/clay nanocomposites more comprehensive studies on the thermal stability of surfactants in the processing temperatures of these materials are necessary. In this work, the thermal stability of four quaternary ammonium salts such as hexadecyltrimethyl ammonium bromide, alkyldimethylbenzyl ammonium chloride, esthearildimethyl ammonium chloride and hexadecyltrimethyl ammonium chloride was evaluated for their intercalation into national bentonite clay, with the aim to enable organophilic for using in polymer nanocomposites. The salts were thermally characterized by differential

  5. Aqueous two-phase system based on natural quaternary ammonium compounds for the extraction of proteins.

    Science.gov (United States)

    Zeng, Chao-Xi; Xin, Rui-Pu; Qi, Sui-Jian; Yang, Bo; Wang, Yong-Hua

    2016-02-01

    Aqueous two-phase systems, based on the use of natural quaternary ammonium compounds, were developed to establish a benign biotechnological route for efficient protein separation. In this study, aqueous two-phase systems of two natural resources betaine and choline with polyethyleneglycol (PEG400/600) or inorganic salts (K2 HPO4 /K3 PO4 ) were formed. It was shown that in the K2 HPO4 -containing aqueous two-phase system, hydrophobic interactions were an important driving force of protein partitioning, while protein size played a vital role in aqueous two-phase systems that contained polyethylene glycol. An extraction efficiency of more than 90% for bovine serum albumin in the betaine/K2 HPO4 aqueous two-phase system can be obtained, and this betaine-based aqueous two-phase system provided a gentle and stable environment for the protein. In addition, after investigation of the cluster phenomenon in the betaine/K2 HPO4 aqueous two-phase systems, it was suggested that this phenomenon also played a significant role for protein extraction in this system. The development of aqueous two-phase systems based on natural quaternary ammonium compounds not only provided an effective and greener method of aqueous two-phase system to meet the requirements of green chemistry but also may help to solve the mystery of the compartmentalization of biomolecules in cells.

  6. POLYMER—SUPPORTED SINGLE AND MIXED AMMONIUM AND PHOSPHONIUM SALTS AS CATALYSTS FOR PHASE—TRANSFER REACTIONS

    Institute of Scientific and Technical Information of China (English)

    POPAAdrian; PARVULESCUViorica; 等

    2001-01-01

    In this study was to investigate,by phase-transfer catalysis,the activity of single and mixed ammonium and phosphonium salts grafted on a "gel-type" stryene-7% divinylbenzene copolymer in the oxidation of benzyl alcohol with hydrogen peroxide.A wide variety of catalysts with different quaternary groups and different quaternary chain length substitutents were examined.The activity of single"onium"salts increases as a consequence of the association of ammonium and phosphonium salts grafted onn the same polymeric support.The activity of polymer-supported ammonium and phosphonium salts increases with the number of carbon atoms contained in the alkyl radicals of the -onium and of the functionalization degree with phosphonium groups.

  7. POLYMER-SUPPORTED SINGLE AND MIXED AMMONIUM AND PHOSPHONIUM SALTS AS CATALYSTS FOR PHASE-TRANSFER REACTIONS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In this study was to investigate, by phase-transfer catalysis, the activity of single and mixed ammonium and phosphonium salts grafted on a "gel-type" styrene-7% divinylbenzene copolymer in the oxidation of benzyl alcohol with hydrogen peroxide.A wide variety of catalysts with different quaternary groups and different quaternary chain length substituents were examined.The activity of single "onium" salts increases as a consequence of the association of ammonium and phosphonium salts grafted on the same polymeric support. The activity of polymer-supported ammonium and phosphonium salts increases with the number of carbon atoms contained in the alkyl radicals of the -onium and of the functionalization degree with phosphonium groups.

  8. Quaternary ammonium derivatives as spasmolytics for irritable bowel syndrome.

    Science.gov (United States)

    Evangelista, S

    2004-01-01

    Quaternary ammonium derivatives such as cimetropium, n-butyl scopolammonium, otilonium and pinaverium bromide have been discovered and developed as potent spasmolytics of the gastrointestinal tract. Their pharmacological activity has been proven in both "in vivo" and "in vitro" studies of hypermotility. "In vitro" experiments showed that they possess antimuscarinic activity at nM level but only pinaverium and otilonium are endowed with calcium channel blocker properties. These latter compounds relaxed the gastrointestinal smooth muscle mainly through a specific inhibition of calcium ion influx through L-type voltage operated calcium channels. Molecular pharmacology trials have indicated that pinaverium and otilonium can bind specific subunits of the calcium channel in the external surface of the plasma membrane and in this way they block the machinery of the contraction. Recent evidence showed that otilonium is able to bind tachykinin NK(2) receptors and not only inhibits one of the major contractile agents but can reduce the activation of afferent nerves devoted to the passage of sensory signals from the periphery to the central nervous system. Thanks to their typical physico-chemical characteristics, they are poorly absorbed by the systemic circulation and generally remain in the gastrointestinal tract where they exert the muscle relaxant activity by a local activity. Some differences exists in the absorption among these compounds: both n-butyl scopolammonium and cimetropium are partially taken up in the bloodstream, pinaverium has a low absorption (8-10 %) but is endowed with an excellent hepato-biliary excretion and otilonium, which has the lowest absorption (3 %), is almost totally excreted by faeces. Quaternary ammonium derivatives are widely used for the treatment of irritable bowel syndrome and recent meta-analyses have supported their efficacy in this disease. Due to its therapeutic index, the use of n-butyl scopolammonium is more indicated to treat acute

  9. Effects of quaternary ammonium silane coatings on mixed fungal and bacterial biofilms on tracheoesophageal shunt prostheses

    NARCIS (Netherlands)

    Oosterhof, JJH; Buijssen, KJDA; Busscher, HJ; van der Laan, BFAM; van der Mei, HC

    2006-01-01

    Two quaternary ammonium silanes (QAS) were used to coat silicone rubber tracheoesophageal shunt prostheses, yielding a positively charged surface. One QAS coating [(trimethoxysilyl)-propyidimethylocta-decylammonium chloride] was applied through chemical bonding, while the other coating, Biocidal ZF,

  10. Antibacterial Activity of Dental Cements Containing Quaternary Ammonium Polyethylenimine Nanoparticles

    Directory of Open Access Journals (Sweden)

    Nurit Beyth

    2012-01-01

    Full Text Available Glass ionomer cements (GICs are commonly used for cementing full cast crown restorations. Regrettably, although the dental cements fill the gap between the tooth and the crown, bacterial microleakage may occur, resulting in secondary caries. As microleakage cannot be completely prevented, GICs possessing antibacterial properties are in demand. In the present study the antibacterial activity of insoluble, cross-linked quaternary ammonium polyethylenimine (QPEI nanoparticles incorporated at 1% w/w in two clinically available GICs were studied. The antibacterial activity was tested against Streptococcus mutans and Lactobacillus casei using the direct contact test (DCT and the agar diffusion test (ADT. Using the direct contact test, antibacterial activity (<0.05 was found in both tested GICs with incorporated QPEI nanoparticles, the effect lasting for at least one month. However, the ADT showed no inhibition halo in the test bacteria, indicating that the antimicrobial nanoparticles do not diffuse into the agar. The results show that the incorporation of QPEI nanoparticles in glass ionomer cements has a long-lasting antibacterial effect against Streptococcus mutans and Lactobacillus casei. Changing the antibacterial properties of glass ionomer cements by incorporating QPEI antibacterial nanoparticles may prolong the clinical performance of dental crowns.

  11. Quaternary ammonium sulfanilamide: a membrane-impermeant carbonic anhydrase inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Henry, R.P.

    1987-05-01

    A novel carbonic anhydrase (CA) inhibitor, quaternary ammonium sulfanilamide (QAS), was tested for potency as a CA inhibitor and for its ability to be excluded from permeating biological membranes. Inhibitor titration plots of QAS vs. pure bovine CA II and CA from the gills of the blue crab, Callinectes sapidus, yielded K/sub i/ values of approx. 15 ..mu..M; thus QAS is a relatively weak but effective CA inhibitor. Permeability of the QAS was directly tested by two independent methods. The inhibitor was excluded from human erythrocytes incubated in 5 mM QAS for 24 h as determined using an /sup 18/O-labeled mass spectrometer CA assay for intact cells. Also QAS injected into the hemolymph of C. sapidus (1 or 10 mM) did not cross the basal membrane of the gill. The compound was cleared from the hemolymph by 96 h after injection, and at no time during that period could the QAS be detected in homogenates of gill tissue. Total branchial CA activity was only slightly reduced following the QAS injection. These data indicate that QAS is a CA inhibitor to which biological membranes are impermeable and that can be used in vivo and in vitro in the study of membrane-associated CA.

  12. Interaction of ochratoxin A with quaternary ammonium beta-cyclodextrin.

    Science.gov (United States)

    Poór, Miklós; Kunsági-Máté, Sándor; Szente, Lajos; Matisz, Gergely; Secenji, Györgyi; Czibulya, Zsuzsanna; Kőszegi, Tamás

    2015-04-01

    Ochratoxin A (OTA) is a widely spread nephrotoxic food contaminant mycotoxin. Unfortunately, attenuation or prevention of the toxic effects of OTA is still an unresolved problem. Molecular inclusion of OTA by cyclodextrins (CDs) results in complexes with low stability. In the human organism, OTA exists mostly in the dianionic state (OTA(2-)). Therefore, our major goal was to develop a chemically modified cyclodextrin which gives a more stable complex with OTA than the previously published derivatives and which shows stronger preference towards OTA(2-). In our fluorescence spectroscopic study we demonstrate that quaternary ammonium beta-cyclodextrin (QABCD) fulfils both of these requirements. The calculated stability constant of the QABCD-OTA(2-) complex was 28,840 M(-1) (about 200-fold higher than that of the β-CD-OTA(2-) complex). We hypothesize, that QABCD may be a suitable tool for the decontamination of different OTA-contaminated drinks; furthermore, for alleviation of the toxic effects of OTA, such complex formation may reduce its absorption from the intestine.

  13. Synthesis of a nano-antibacterial inorganic filler containing a quaternary ammonium salt with long chain alkyl and ;its effect on dental resin composites%含长链烷基季铵盐的纳米抗菌无机填料的合成及其在牙科复合树脂中的应用研究

    Institute of Scientific and Technical Information of China (English)

    吴峻岭; 周凯运; 朱婷; 周传健

    2014-01-01

    目的:设计合成新型的含长链烷基季铵盐的纳米抗菌无机填料,以赋予牙科复合树脂更优良的抗菌性能。方法在分子设计和筛选的基础上,制备了长链烷基季铵盐修饰的纳米抗菌二氧化硅填料,并对填料的抗菌性能进行评价。为进一步提高抗菌填料与树脂的结合力,采用硅烷偶联剂对抗菌填料表面进行了处理,并用红外光谱法对其结构特征进行分析;然后将新型纳米抗菌无机填料加入牙科复合树脂中,观察其在复合树脂基体中的分散情况,同时与商品化的TetricN-Ceram纳米瓷化复合树脂进行对比;并以变异链球菌为对象,研究复合树脂的抗菌性能。结果长链烷基季铵盐成功接枝到纳米二氧化硅颗粒表面;新型纳米抗菌无机填料的抗菌性能优于含短链烷基季铵盐的抗菌无机填料;偶联处理后的纳米抗菌无机填料在树脂基体中分散均匀,与树脂结合紧密,与TetricN-Ceram纳米瓷化复合树脂类似;改性后的复合树脂抗菌性能良好。结论含长链烷基季铵盐的纳米抗菌无机填料抗菌性能良好,经过表面偶联处理后可以很好地与牙科复合树脂共混,提高了牙科复合树脂的抗菌性能。%Objective This study aimed to synthesize a novel nano-antibacterial inorganic filler that contains a quaternary ammonium salt with long chain alkyl and to report the antibacterial property of dental resin composites. Methods A novel nano-antibacterial inorganic filler that contains a quaternary ammonium salt with long chain alkyl was synthesized based on previous research. The antibacterial property of the filler was measured. The surface of the novel nano-antibacterial inorganic filler was modified by a coupling agent to achieve a good interfacial bonding between the filler and the resin matrix. Infrared spectrum analysis was carried out. The modified novel nano-antibacterial inorganic fillers were

  14. Synthesis of Main-Chain Chiral Quaternary Ammonium Polymers for Asymmetric Catalysis Using Quaternization Polymerization

    Directory of Open Access Journals (Sweden)

    Md. Masud Parvez

    2012-06-01

    Full Text Available Main-chain chiral quaternary ammonium polymers were successfully synthesized by the quaternization polymerization of cinchonidine dimer with dihalides. The polymerization occurred smoothly under optimized conditions to give novel type of main-chain chiral quaternary ammonium polymers. The catalytic activity of the polymeric chiral organocatalysts was investigated on the asymmetric benzylation of N-(diphenylmethylideneglycine tert-butyl ester.

  15. Synthesis of his-quaternary ammonium peroxotungstates (peroxomolybdates)and their catalytic activity in oxidation of alcohols by aqueous H2O2

    Institute of Scientific and Technical Information of China (English)

    SHI Xianying; WEI Junfa

    2007-01-01

    Three kinds of bis-quaternary ammonium salts of peroxotungstate and peroxomolybdate,such as PhCH2NO(O2)2(C2O4)] and PhCH2N(CH2)6NCH2Ph [MoO(O2)2(C2Oa)],have been synthesized and characterized.Their catalytic activity in the oxidation of cyclohexanol and benzyl alcohol was investigated with only aqueous 30% hydrogen peroxide.The results show that the bis-quaternary ammonium peroxotungstates are excellent catalysts in the oxidation of benzyl alcohol and cyclohexanol under moderate conditions.However,the catalytic ability of bis-quaternary ammonium peroxomolybadates is relatively poor.The yields of benzyl acid,benzaldehyde,and cyclohexanone reached up to 93.0%,93.6%,and 91.7%,respectively.

  16. Cationic nanoparticles with quaternary ammonium-functionalized PLGA-PEG-based copolymers for potent gene transfection

    Science.gov (United States)

    Wang, Yan-Hsung; Fu, Yin-Chih; Chiu, Hui-Chi; Wang, Chau-Zen; Lo, Shao-Ping; Ho, Mei-Ling; Liu, Po-Len; Wang, Chih-Kuang

    2013-11-01

    The objective of the present work was to develop new cationic nanoparticles (cNPs) with amphiphilic cationic copolymers for the delivery of plasmid DNA (pDNA). Cationic copolymers were built on the synthesis of quaternary ammonium salt compounds from diethylenetriamine (DETA) to include the positively charged head group and amphiphilic multi-grafts. PLGA- phe-PEG- qDETA (PPD), phe-PEG- qDETA-PLGA (PDP), and PLGA- phe-PEG- qDETA-PLGA (PPDP) cationic copolymers were created by this moiety of DETA quaternary ammonium, heterobifunctional polyethylene glycol (COOH-PEG-NH2), phenylalanine ( phe), and poly(lactic- co-glycolic acid) (PLGA). These new cNPs were prepared by the water miscible solvent displacement method. They exhibit good pDNA binding ability, as shown in a retardation assay that occurred at a particle size of 217 nm. The zeta potential was approximately +21 mV when the cNP concentration was 25 mg/ml. The new cNPs also have a better buffering capacity than PLGA NPs. However, the pDNA binding ability was demonstrated starting at a weight ratio of approximately 6.25 cNPs/pDNA. Gene transfection results showed that these cNPs had transfection effects similar to those of Lipofectamine 2000 in 293T cells. Furthermore, cNPs can also transfect human adipose-derived stem cells. The results indicate that the newly developed cNP is a promising candidate for a novel gene delivery vehicle.

  17. Cationic nanoparticles with quaternary ammonium-functionalized PLGA–PEG-based copolymers for potent gene transfection

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yan-Hsung [Kaohsiung Medical University, School of Dentistry, College of Dental Medicine (China); Fu, Yin-Chih [Kaohsiung Medical University, Graduate Institute of Medicine, College of Medicine (China); Chiu, Hui-Chi [Kaohsiung Medical University, Department of Medicinal and Applied Chemistry, College of Life Science (China); Wang, Chau-Zen [Kaohsiung Medical University, Department of Physiology, College of Medicine (China); Lo, Shao-Ping [Kaohsiung Medical University, Department of Medicinal and Applied Chemistry, College of Life Science (China); Ho, Mei-Ling [Kaohsiung Medical University, Department of Physiology, College of Medicine (China); Liu, Po-Len [Kaohsiung Medical University, Department of Respiratory Therapy, College of Medicine (China); Wang, Chih-Kuang, E-mail: ckwang@kmu.edu.tw [Kaohsiung Medical University, Department of Medicinal and Applied Chemistry, College of Life Science (China)

    2013-11-15

    The objective of the present work was to develop new cationic nanoparticles (cNPs) with amphiphilic cationic copolymers for the delivery of plasmid DNA (pDNA). Cationic copolymers were built on the synthesis of quaternary ammonium salt compounds from diethylenetriamine (DETA) to include the positively charged head group and amphiphilic multi-grafts. PLGA-phe-PEG-qDETA (PPD), phe-PEG-qDETA-PLGA (PDP), and PLGA-phe-PEG-qDETA-PLGA (PPDP) cationic copolymers were created by this moiety of DETA quaternary ammonium, heterobifunctional polyethylene glycol (COOH-PEG-NH{sub 2}), phenylalanine (phe), and poly(lactic-co-glycolic acid) (PLGA). These new cNPs were prepared by the water miscible solvent displacement method. They exhibit good pDNA binding ability, as shown in a retardation assay that occurred at a particle size of ∼217 nm. The zeta potential was approximately +21 mV when the cNP concentration was 25 mg/ml. The new cNPs also have a better buffering capacity than PLGA NPs. However, the pDNA binding ability was demonstrated starting at a weight ratio of approximately 6.25 cNPs/pDNA. Gene transfection results showed that these cNPs had transfection effects similar to those of Lipofectamine 2000 in 293T cells. Furthermore, cNPs can also transfect human adipose-derived stem cells. The results indicate that the newly developed cNP is a promising candidate for a novel gene delivery vehicle.

  18. Direct esterification of ammonium salts of carboxylic acids

    Science.gov (United States)

    Halpern, Yuval

    2003-06-24

    A non-catalytic process for producing esters, the process comprising reacting an ammonium salt of a carboxylic acid with an alcohol and removing ammonia from the reaction mixture. Selectivities for the desired ester product can exceed 95 percent.

  19. Synthesis and antibacterial activity screening of quaternary ammonium derivatives of triazolyl pyranochromenones

    Indian Academy of Sciences (India)

    PREETI YADAV; BIPUL KUMAR; HEMANT K GAUTAM; SUNIL K SHARMA

    2017-02-01

    A series of quaternary ammonium derivatives of triazolyl pyranochromen-2-ones have been synthesized and characterized; their antibacterial potential were investigated against two gram negative (Pseudomonas aeruginosa and Escherichia coli) and two gram positive bacterial strains (Bacillus cereus and Staphylococcus aureus). In order to develop structure-activity relationship (SAR), the effect of varying the substituent (R) at the C-10 position of pyranochromen-2-one as well as the length of the spacer (n) between the triazolyl pyranochromen-2-ones and quaternary ammonium group, on the antibacterial activity of compoundshas been evaluated. Some of the screened compounds exhibited antibacterial potential against the studied strains in the microgram range.

  20. 天然高分子改性异喹啉季铵盐对SRB杀菌性能及机理的研究%A Study of Bactericidal Effect of Natural Polymeric Modified Isoquinoline Quaternary Ammonium Salt on Sulfate Reducing Bacteria(SRB) and Mechanism

    Institute of Scientific and Technical Information of China (English)

    潘碌亭; 肖锦

    2001-01-01

    The bactericidal effect of natural polymeric modified isoquinoline quaternary ammonium salt(FIQ-C)on sulfate reducing bacteria (SRB) was studied using the vanishing- dilution method. Factors affecting the bactericidal ef- ficiency were investigated, the bectericidal ability of FIQ-C was compared with that of 1227, and the bactericidal mechanism of FIQ-C was approached. The result shows that FIQ - C has a good bactericidal effect on the SRB in sim- ulated oil field waste water and that when the addition of FIQ - C is 5 mg/L, the bactericidal rate may be 99.9% or higher.%采用绝迹稀释法研究了天然高分子改性异喹啉季铵盐(FIQ-C)对硫酸盐还原菌(SRB)的杀灭性能。考察了各种因素对杀菌性能的影响,比较了药剂FIQ-C与1227的杀菌能力,探讨了FIQ-C的杀菌机理。结果表明,药FIQ-C对模拟油田废水中SRB有良好的杀灭性能,当FIQ-C投加量为5 mg/L时,杀菌率可达99.9%以上。

  1. DESIGN, SYNETHESIS, DYE-LOADING AND HOST-GUEST COLORING APPLICATION OF AMPHIPHILIC HYPERBRANCHED POLY (QUATERNARY AMMONIUM SALT) S%两亲性全季铵盐超支化聚合物的设计与合成及主-客体超分子着色应用研究

    Institute of Scientific and Technical Information of China (English)

    唐爱金; 韩金; 翁祝林; 高超

    2013-01-01

    A novel AB2-type monomer with one azide group and two alkyne groups and two quaternary ammonium salt units was synthesized via highly efficient thiol-yne click chemistry and Menschutkin reaction. The synthetic protocol includes three steps; (1) 4-oxo-4-( prop-2-ynyloxy ) butanoic acid 1 reacts with 3-( dimethylamino) -1-propanethiol via thiol-yne click chemistry to obtain intermediate 2 containing one carboxyl group and two dimethyamino groups with high yield ( ~97. 5% ) , (2) esterification between carboxyl group of 2 and 2-azidoethanol to afford intermediate 3,(3) fast click-like Menschutkin quaterization of the two dimethylamino groups of 3 with propargyl bromide to give the final AB2-type monomer 4 possessing one azide group,two alkyne groups and two quaternary ammonium salt units. The monomer structure was confirmed by NMR,FT-IR and MS. The subsequent click polymerization of 4 gave rise to quaternary ammonium salt-type hyperbranched polymers. End-capping the polymers with azide-terminated alkyl long chains resulted in amphiphilic hyperbranched polymers ( AHPs ) with hydrophilic quaternary ammonium salt core and hydrophobic alkyl shell. The AHPs were characterized by H-NMR,FTIR, and gel permeation chromatography ( GPC ) measurements. The AHPs have number-average molecular weights ( Mn ) of 3800 ~ 5300 and narrow polydispersity index (PDI,1. 17 ~ 1. 27) . The host-guest dye-encapsulation property of AHPs was investigated using congo red ( CR ) , methyl orange ( MO ) , methyl violet ( MV ) , methyl blue ( MB ) , eosin Y ( EY ) , iluorescein sodium (FS) and rose Bengal (RB) as guests with UV-Vis spectrometer. The AHPs exhibited high capabilities to load water-soluble dyes due to their polarity difference between core and shell, and the dye-transfer percentage from water to chloroform phase reached 93% ~99% for MO,MV,FS,and EY,and 71% ~ 76% for RB and CR. The average numbers of dye molecules trapped per macromolecule achieved 0. 5 ~ 0. 6 for MO

  2. Epoxidation of Alkenes with Aqueous Hydrogen Peroxide and Quaternary Ammonium Bicarbonate Catalysts

    DEFF Research Database (Denmark)

    Mielby, Jerrik Jørgen; Kegnæs, Søren

    2013-01-01

    A range of solid and liquid catalysts containing bicarbonate anions were synthesised and tested for the epoxidation of alkenes with aqueous hydrogen peroxide. The combination of bicarbonate anions and quaternary ammonium cations opens up for new catalytic systems that can help to overcome...

  3. Synthesis of hierarchical zeolites using an inexpensive mono-quaternary ammonium surfactant as mesoporogen.

    Science.gov (United States)

    Zhu, Xiaochun; Rohling, Roderigh; Filonenko, Georgy; Mezari, Brahim; Hofmann, Jan P; Asahina, Shunsuke; Hensen, Emiel J M

    2014-12-04

    A simple amphiphilic surfactant containing a mono-quaternary ammonium head group (N-methylpiperidine) is effective in imparting substantial mesoporosity during synthesis of SSZ-13 and ZSM-5 zeolites. Highly mesoporous SSZ-13 prepared in this manner shows greatly improved catalytic performance in the methanol-to-olefins reaction compared to bulk SSZ-13.

  4. Complete genome sequence of Campylobacter jejuni RM1246-ERRC that exhibits resistance to Quaternary Ammonium Compounds

    Science.gov (United States)

    Campylobacter jejuni strain RM1246-ERRC is a clinical isolate. In laboratory experiments RM1246-ERRC exhibited resistance to the antimicrobial effects of quaternary ammonium compounds (QACs) when compared to other C. jejuni strains. The chromosome of RM1246-ERRC was determined to be 1,659,694 bp w...

  5. Mechanism of Osmotic Activation of the Quaternary Ammonium Compound Transporter (QacT) of Lactobacillus plantarum

    NARCIS (Netherlands)

    Glaasker, Erwin; Heuberger, Esther H.M.L.; Konings, Wil N.; Poolman, Bert

    1998-01-01

    The accumulation of quaternary ammonium compounds in Lactobacillus plantarum is mediated via a single transport system with a high affinity for glycine betaine (apparent Km of 18 μM) and carnitine and a low affinity for proline (apparent Km of 950 μM) and other analogues. Mutants defective in the

  6. Long alkyl chain bis-quaternary ammonium-based ionic liquids as biologically active xanthene dyes

    Energy Technology Data Exchange (ETDEWEB)

    Pernak, Juliusz; Swierczynska, Anna; Walkiewicz, Filip [Poznan Univ. of Technology, Poznan (Poland). Faculty of Chemical Technology; Krystkowiak, Ewa [A. Mickiewicz University, Poznan, (Poland). Faculty of Chemistry; Maciejewski, Andrzej [A. Mickiewicz University, Poznan (Poland). Centre of Ultrafast Laser Spectroscopy

    2009-07-01

    New examples of air- and moisture-stable, hydrophobic and hydrophilic bis-quaternary ammonium derived ionic liquids have been prepared. These ionic liquids have been proposed to act as biological active dyes with characteristic unique physicochemical properties, providing alternatives to some conventional anionic xanthene dyes such as eosine Y, fluorescein and erythrosine. (author)

  7. Different virucidal activities of hyperbranched quaternary ammonium coatings on poliovirus and influenza virus

    NARCIS (Netherlands)

    Tuladhar, E.; Koning, M.C. de; Fundeanu, I.; Beumer, R.; Duizer, E.

    2012-01-01

    Virucidal activity of immobilized quaternary ammonium compounds (IQACs) coated onto glass and plastic surfaces was tested against nveloped influenza A (H1N1) virus and nonenveloped poliovirus Sabin1. The IQACs tested were virucidal against the influenza virus within 2 min, but no virucidal effect ag

  8. Different virucidal activities of hyperbranched quaternary ammonium coatings on poliovirus and influenza virus

    NARCIS (Netherlands)

    Tuladhar, E.; Koning, de M.C.; Fundeanu, I.; Beumer, R.R.; Duizer, E.

    2012-01-01

    Virucidal activity of immobilized quaternary ammonium compounds (IQACs) coated onto glass and plastic surfaces was tested against enveloped influenza A (H1N1) virus and nonenveloped poliovirus Sabin1. The IQACs tested were virucidal against the influenza virus within 2 min, but no virucidal effect

  9. A Synthetic Route to Quaternary Pyridinium Salt-Functionalized Silsesquioxanes

    Directory of Open Access Journals (Sweden)

    Nataliya Kostenko

    2012-01-01

    Full Text Available A synthetic route to potentially biocidal silsesquioxanes functionalized by quaternary pyridinium functionalities has been developed. N-Alkylation reactions of the precursor compounds 4-(2-(trimethoxysilylethyl-pyridine (5 and 4-(2-trichloro-silylethylpyridine (6 with iodomethane, n-hexylbromide, and n-hexadecylbromide cleanly afforded the corresponding N-alkylpyridinium salts (7–10. The synthesis of a 4-(2-ethylpyridine POSS derivative (2 was achieved by capping of the silsesquioxane trisilanol Cy7Si7O9(OH3 (1 via two different preparative routes. Attempts to use compound 2 as precursor for quaternary pyridinium salt-functionalized POSS derivatives were met with only partial success. Only the reaction with iodomethane cleanly afforded the new N-methylpyridinium salt 12 in high yield, whereas n-hexylbromide and n-hexadecylbromide failed to react with 2 even under forcing conditions.

  10. 75 FR 14082 - Ammonium Salts of Fatty Acids (C8

    Science.gov (United States)

    2010-03-24

    ... diet of humans, animals, and plants and currently have Food and Drug Administration and EPA approved.../kg/day (6 times the limit dose of 1,000 mg/kg/day) on days 2 to 13 of pregnancy and musculo-skeletal... plants. Ammonium salts of fatty acid are not likely to persist in the environment and are expected to...

  11. Hydrolysis of cellulose catalyzed by quaternary ammonium perrhenates in 1-allyl-3-methylimidazolium chloride.

    Science.gov (United States)

    Wang, Jingyun; Zhou, Mingdong; Yuan, Yuguo; Zhang, Quan; Fang, Xiangchen; Zang, Shuliang

    2015-12-01

    Quaternary ammonium perrhenates were applied as catalyst to promote the hydrolysis of cellulose in 1-allyl-3-methylimidazolium chloride ([Amim]Cl). The quaternary ammonium perrhenates displayed good catalytic performance for cellulose hydrolysis. Water was also proven to be effective to promote cellulose hydrolysis. Accordingly, 97% of total reduced sugar (TRS) and 42% of glucose yields could be obtained under the condition of using 5mol% of tetramethyl ammonium perrhenate as catalyst, 70μL of water, ca. 0.6mmol of microcrystalline cellulose (MCC) and 2.0g of [Amim]Cl as solvent under microwave irradiation for 30min at 150°C (optimal conditions). The influence of quaternary ammonium cation on the efficiency of cellulose hydrolysis was examined based on different cation structures of perrhenates. The mechanism on perrhenate catalyzed cellulose hydrolysis is also discussed, whereas hydrogen bonding between ReO4 anion and hydroxyl groups of cellulose is assumed to be the key step for depolymerization of cellulose. Copyright © 2015. Published by Elsevier Ltd.

  12. 含咪唑环不对称双季铵盐的合成及缓蚀性能研究%synthesis and corrosion inhibition performance of the asymmetric bis Quaternary ammonium salt containinG imidaZole rinG

    Institute of Scientific and Technical Information of China (English)

    余宗学; 梁灵; 何毅; 马瑜; 李飞; 陈映晓

    2014-01-01

    成功合成了含咪唑环不对称双季铵盐,通过失重法、电化学阻抗谱、动电位扫描极化曲线、扫描电镜对合成产物在3% NaCl的饱和二氧化碳溶液中的缓蚀效率进行研究。结果表明,其在饱和二氧化碳溶液中对钢铁有着良好的缓蚀作用,缓蚀效率接近90%;运用Langmuir吸附等温式对吸附行为进行了拟合,表明其吸附类型符合Lang-muir吸附模型,吸附方式为化学吸附。%The asymmetric bis quaternary ammonium salt containing imidazole ring was synthesised suc-cessfully. And weight-loss method,electrochemical impedance spectroscopy,potentiodynamic polarization curve,scanning electron microscopy was used to study on the inhibition efficiency of this product in sodi-um chloride solutions(3. 00%)bubbled with CO2-saturated. The result shows that it has good corrosion inhibition for the P110 steel in this solution,and the corrosion inhibition efficiency is closed to 90%. The adsorption behavior was fitted using the Langmuir adsorption isotherm,and showed that the adsorption type conforms to the Langmuir adsorption isotherm,its adsorption mode is chemical adsorption.

  13. β-CD assisted dissolution of quaternary ammonium permanganates in aqueous medium.

    Science.gov (United States)

    Bank, Suraj Prakash; Guru, Partha Sarathi; Dash, Sukalyan

    2014-10-13

    The non-polar internal cavity of β-cyclodextrin (β-CD) has been exploited for the entrapment of the hydrophobic tails of two water insoluble quaternary ammonium permanganates (QAPs): cetyltrimethylammonium permanganate (CTAP) and tetrabutylammonium permanganate (TBAP), for solubilization in aqueous medium. The solubilization and organizational behavior of the QAPs in aqueous β-CD solution have been determined from the comparison of their rates of self-oxidation in presence and in absence of β-CD. Effect of QAP concentration on their observed rate constants (k(obs)) at a fixed β-CD concentration, phase solubility analysis in varying β-CD concentration, impact of quaternary ammonium bromides (QABs) on the kobs values of CTAP and TBAP at fixed QAP and β-CD concentrations, and the temperature effect have been reported. A scheme to explain the solvation of QAPs in aqueous β-CD has been proposed based on dynamic light scattering (DLS) analysis of the samples.

  14. Synthesis and surface-active property of bis-quaternary ammonium-sodium sulfate Gemini surfactant

    Institute of Scientific and Technical Information of China (English)

    Zhao Qiuling; Gao Zhinong

    2006-01-01

    N,N-dimethyldodecylamine,hydrochloride and epichlorohydrin (molar ration is 2:1:1) were used to synthesize bis-quaternary ammonium Gemini surfactant with a hydroxyl in its spacer group by the one-pot method.This hydroxyl was sulfonated by chlorosulfonic acid and then neutralized to bis-quaternary ammonium-sodium sulfate zwitterionic Gemini surfactant.The yield of the final product was 78%,and the melting point was 231-233℃.Its structure was characterized by IR,1H-NMR,MS,and elemental analyses.The critical micelle concentration (cmc)and surface tension of the novel zwitterionic Gemini surfactant in aqueous solution at 15℃ are 7.2×10-5 mol/L and 34.5 mN/m,respectively.

  15. Simultaneous adsorption/desorption of quaternary ammonium herbicides by acid vineyard soils

    Science.gov (United States)

    Conde Cid, Manuel; Paradelo Núñez, Remigio; Fernández Calviño, David; Nóvoa Muñoz, Juan Carlos; Arias Estévez, Manuel

    2017-04-01

    Competitive adsorption and desorption of three quaternary ammonium herbicides (paraquat, diquat, and difenzoquat) have been studied in four sandy-loam acid vineyard soils from NW Spain and Portugal. The soils present organic matter contents between 3 and 48 g kg-1 and copper contents ranging from 25 to 107 mg kg-1. Adsorption has been studied under equilibrium conditions in batch experiments, and kinetics were studied in a stirred-flow chamber. Adsorption and desorption followed a Freundlich model and kinetics were well described by the pseudo-first-order model. The retention capacity for the pesticides by the four soils followed the sequence: paraquat > diquat > difenzoquat. The different adsorption capacities of each soil were not related to pH, clay or organic matter contents, as could be expected, but rather to soil copper content. The results show that competition with copper for adsorption sites is an important factor in quaternary ammonium herbicides retention in soils with these characteristics.

  16. Anti-Caries Effects of Dental Adhesives Containing Quaternary Ammonium Methacrylates with Different Chain Lengths

    OpenAIRE

    Qi Han; Bolei Li; Xuedong Zhou; Yang Ge; Suping Wang; Mingyun Li; Biao Ren; Haohao Wang; Keke Zhang; Hockin H. K. Xu; Xian Peng; Mingye Feng; Michael D. Weir; Yu Chen; Lei Cheng

    2017-01-01

    The objectives of this study were to investigate the effects of dental adhesives containing quaternary ammonium methacrylates (QAMs) with different alkyl chain lengths (CL) on ecological caries prevention in vitro. Five QAMs were synthesized with a CL = 3, 6, 9, 12, and 16 and incorporated into adhesives. Micro-tensile bond strength and surface charge density were used to measure the physical properties of the adhesives. The proportion change in three-species biofilms consisting of Streptococ...

  17. Preparation of Quaternary Ammonium Salt Modified Graphene Oxide and Its Properties%季铵盐改性氧化石墨烯的制备及其性能研究

    Institute of Scientific and Technical Information of China (English)

    惠昱晨; 马晓燕; 陈智群; 张皋; 宋颖; 侯秀璋

    2013-01-01

    本论文采用改进的Hummers法制备了氧化石墨烯(GO),并将氧化石墨烯用十二烷基二甲基苄基氯化铵(1227)进行修饰,得到1227非共价改性的氧化石墨烯(GO-1227).用拉曼光谱、漫反射红外光谱分析、X-射线光电子表面能谱技术表征了其化学结构;用X-射线衍射分析、扫描电子显微镜与透射电子显微镜观察了其剥离情况和微观形貌;分析了它们在不同溶剂中的分散性.结果表明,季铵盐改性后,1227阳离子通过静电作用插入到GO片层之间,使GO片层进一步剥离,且在极性较弱的有机溶剂中的溶解性增加.热失重分析表明,GO-1227的初始分解温度提高了约70℃.将GO-1227与聚甲基丙烯酸甲酯与苯乙烯的嵌段共聚物(PMMA-b-PS)凝胶聚电解质复合,制备了纳米复合凝胶聚合物电解质(NGPE),并用交流阻抗法测试其电性能,发现占聚电解质总质量2%的GO-1227可以将其离子电导率提高8.6倍.%Graphene oxide (GO) was prepared by the modified Hummers method,and modified by dodecyl dimethyl benzyl ammonium chloride (1227) to produce 1227 non-covalent modified graphene oxide (GO-1227). Raman spectrum, Diffuse reflection infrared spectroscopy and X-ray photoelectron spectroscopy were used to characterize the chemical structure of GO-1227. X-ray diffraction was used to observe the exfoliated morphology of GO-1227. It is found that the layers of GO became more complete disordered and exfoliated after modified by 1227. Scanning electron microscope and Transmission electron microscope was used to characterize the micro structure of GO-1227. The results show that GO-1227 presented curling and folded layer structure. The disperse property of GO-1227 was measured and thermal stability of GO and GO-1227 was compared by thermogravimetry analysis. The solubility of GO-1227 was enhanced in the relatively weak polar solvent since the 1227 cations surround the layers of GO, and thermal stability of GO was

  18. 铵盐功能化氧化石墨烯的制备及其吸附性能%Synthesis and adsorption properties of quaternary ammonium salts functionalized graphene oxide

    Institute of Scientific and Technical Information of China (English)

    王会才; 赵修青; 姚晓霞; 马振华; 王建伟; 柴秀琴

    2015-01-01

    Graphene oxide prepared by Hummers method was firstly washed by alkali solution to remove oxide debris ad-hered on the surface, then was modified through protonation with hydrochloric acid, silanization reaction with (3-aminopropyl)triethoxysilane and quaternization reaction with N-butyl bromide to produce positive charged primary amine salt functionalized graphene oxide (PAS-bwGO). PAS-bwGO was characterized and analyzed by Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, field emission scanning electron microscopy and transmission electron microscopy, and was used preliminary for removal of chromium(VI) in aqueous solution. Results showed that the prepared PAS-bwGO had a high capacity of chromi-um(VI) adsorption, and the maximum adsorption capacity could reach 102 mg/g.%对Hummers法制备的氧化石墨烯进行碱处理去除表面的氧化碎片,经盐酸质子化和3-氨丙基三乙氧基硅烷硅烷化,与溴代正丁烷反应制备出表面带正电荷的铵盐功能化氧化石墨烯(PAS-bwGO),通过傅里叶红外光谱、拉曼光谱、X射线光电子能谱、场发射扫描电镜、透射电镜对其进行表征分析,并初步用于去除水中六价铬Cr(VI)的研究.结果表明,制备的铵盐功能化氧化石墨烯对Cr(VI)有很高的吸附性能,初步测得其饱和吸附量达到102 mg/g.

  19. A Shape-Adaptive, Antibacterial-Coating of Immobilized Quaternary-Ammonium-Compounds Tethered on Hyperbranched Polyurea and its Mechanism of Action

    NARCIS (Netherlands)

    Asri, Lia; Crismaru, Mihaela; Roest, Steven; Chen, Yun; Ivashenko, Oleksii; Rudolf, Petra; Tiller, Joerg C.; van der Mei, Henny C.; Loontjens, Ton J.A.; Busscher, Henk J. Busscher

    2014-01-01

    Quaternary-ammonium-compounds are potent cationic antimicrobials used in everyday consumer products. Surface-immobilized, quaternary-ammonium-compounds create an antimicrobial contact-killing coating. We describe the preparation of a shape-adaptive, contact-killing coating by tethering quaternary-am

  20. 一种松香基双季铵盐和CTAB共混模板介孔SiO2的制备%Preparation of mesoporous silica using a rosin-based bis-quaternary ammonium salt and CTAB as the blend template

    Institute of Scientific and Technical Information of China (English)

    韩世岩; 李淑君; 王威; 宋湛谦

    2013-01-01

    Using a mixture of a rosin-based bis-quaternary ammonium salt and CTAB as a template and tetraethyl orthosilicate as silica source,four kinds of silica materials SiA,SiB,SiC and SiD were prepared based on the alkaline hydrolysis with different proportion of the two surfactants.Their calcination temperature was 550 C,which was determined by TGA.SEM observation showed that SiC and SiD were more homogeneous-dispersed spheroidal particles without agglomeration than SiA and SiB were.According to TEM photographs,SiC and SiD were spheroidal particles with mesoporous structure.FT-IR spectrogram identified the structure of SiC and SiD before and after calcination.Nitrogen adsorption-desorption analysis showed that the pore sizes of SiC and SiD were mainly at 3.8nm,surface areas and cumulative pore volumes of SiC and SiD were 685.29m2/g,1.22cm3/g and 609.73m2/g,0.93cm3/g,respectively.%以一种松香基双季铵盐和CTAB为共混模板,正硅酸乙酯为硅源,通过调节两种表面活性剂的不同用量,在碱性条件下水解制备了SiA、SiB、SiC、SiD 4种SiO2材料.采用TGA确定煅烧温度为550℃;SEM照片分析可知SiC、SiD的微观形貌优于SiA、SiB,且为分散均匀的球形颗粒,无团聚;TEM照片分析可知,SiC、SiD为具有介孔结构的球形颗粒;FT-IR确证了SiC、SiD煅烧前后的基本结构;经氮气吸附-脱附实验分析,结果表明,SiC、SiD的孔径主要集中在3.8nm处,比表面积和累积孔体积分别为685.29m2/g、1.22cm3/g和609.73m2/g、0.93cm3/g.

  1. Enhanced water-solubility, antibacterial activity and biocompatibility upon introducing sulfobetaine and quaternary ammonium to chitosan.

    Science.gov (United States)

    Chen, Yuxiang; Li, Jianna; Li, Qingqing; Shen, Yuanyuan; Ge, Zaochuan; Zhang, Wenwen; Chen, Shiguo

    2016-06-05

    Chitosan (CS) has attracted much attention due to its good antibacterial activity and biocompatibility. However, CS is insoluble in neutral and alkaline aqueous solution, limiting its biomedical application to some extent. To circumvent this drawback, we have synthesized a novel N-quaternary ammonium-O-sulfobetaine-chitosan (Q3BCS) by introducing quaternary ammonium compound (QAC) and sulfobetaine, and its water-solubility, antibacterial activity and biocompatibility were evaluated compare to N-quaternary ammonium chitosan and native CS. The results showed that by introducing QAC, antibacterial activities and water-solubilities increase with degrees of substitution. The largest diameter zone of inhibition (DIZ) was improved from 0 (CS) to 15mm (N-Q3CS). And the water solution became completely transparent from pH 6.5 to pH 11; the maximal waters-solubility was improved from almost 0% (CS) to 113% at pH 7 (N-Q3CS). More importantly, by further introducing sulfobetaine, cell survival rate of Q3BCS increased from 30% (N-Q3CS) to 85% at 2000μg/ml, which is even greater than that of native CS. Furthermore, hemolysis of Q3BCS was dropped sharply from 4.07% (N-Q3CS) to 0.06%, while the water-solution and antibacterial activity were further improved significantly. This work proposes an efficient strategy to prepare CS derivatives with enhanced antibacterial activity, biocompatibility and water-solubility. Additionally, these properties can be finely tailored by changing the feed ratio of CS, glycidyl trimethylammonium chloride and NCO-sulfobetaine.

  2. Critical Coalescence Concetration (CCC as a parameter for evaluation of selected quaternary ammonium compounds

    Directory of Open Access Journals (Sweden)

    Danuta Szyszka

    2013-10-01

    Full Text Available The objective of this paper was to determine the Critical Coalescence Concentration (CCC of surfactants such as N(dodecyloxycarboxymethyl N,N,N-(trimethylammonium bromide (DMGM- 12, N-[2-(dodecyoxycarboxyethyl] N,N,N-(trimethylammonium bromide (DMALM-12 and N-[3- (dodecanoyloxycarboxyprophyl] N,N,N-(trimethylammonium bromide (DMPM-11. The surfactants used represent quaternary ammonium compounds containing a hydrophobic moiety with an ester group (commonly known as “esterquats”. The CCC value was determined by analysis of the relationship between concentration of surfactant and average air bubble diameter. The values of the critical coalescence concentration (CCC were estimated using a graphical method.

  3. Resistance of Pseudomonas to Quaternary Ammonium Compounds. I. Growth in Benzalkonium Chloride Solution

    Science.gov (United States)

    Adair, Frank W.; Geftic, Sam G.; Gelzer, Justus

    1969-01-01

    Resistant cells of Pseudomonas aeruginosa and a waterborne Pseudomonas sp. (strain Z-R) were able to multiply in nitrogen-free minimal salts solution containing various concentrations of commercially prepared, ammonium acetate-buffered benzalkonium chloride (CBC), a potent antimicrobial agent. As the CBC concentration increased, growth increased until a point was reached at which the extent of growth leveled off or was completely depressed. Minimal salts solutions of pure benzalkonium chloride (PBC) containing no ammonium acetate did not support bacterial growth. When ammonium acetate was added to PBC solutions in the same concentrations found in CBC solutions, growth patterns developed that were comparable to those found with CBC. Likewise, (NH4)2SO4 added to PBC solutions supported growth of both organisms. P. aeruginosa was initially resistant to CBC levels of 0.02% and it was adapted to tolerate levels as high as 0.36%. Strain Z-R was naturally resistant to 0.4% CBC. Since ammonium acetate, carried over by the CBC used in drug formulations and disinfectant solutions, has the potential to support the growth of resistant bacteria and thus make possible the risk of serious infection, it is suggested that regulations allowing the presence of ammonium acetate in CBC solution be reconsidered. PMID:4984761

  4. High durability and low toxicity antimicrobial coatings fabricated by quaternary ammonium silane copolymers.

    Science.gov (United States)

    Li, Hairui; Bao, Hongqian; Bok, Ke Xin; Lee, Chi-Ying; Li, Bo; Zin, Melvin T; Kang, Lifeng

    2016-02-01

    Adhesion and subsequent growth of microorganisms on material surfaces are a major concern in many biomedical applications. Currently, various polymers are immobilized on material surfaces to prevent microbial colonization. However, there are several challenges with regard to the coating materials, including their inability to kill microorganisms, complexity of surface grafting, limited durability and toxicity towards humans. To address these challenges, we synthesize a novel quaternary ammonium silane (QAS) antimicrobial copolymer to confer the antimicrobial effect via a simple thermal-curing coating process. The QAS copolymers were less toxic to 3 human cell lines than a commercial antimicrobial QAS monomeric agent, namely, dimethyloctadecyl[3-(trimethoxysilyl) propyl]ammonium chloride (DTPAC). Moreover, the QAS coatings demonstrated superior antimicrobial efficacy and durability than those of the DTPAC coatings. In conclusion, the novel QAS copolymers are useful to prevent substrates from microbial infections, yet with low toxicity to humans and long durability. In addition, the synthetic process is potentially scalable for industrial applications.

  5. 40 CFR 721.6540 - Acrylamide, polymers with tetraalkyl ammonium salt and polyalkyl, aminoalkyl meth-a-cryl-a-mide...

    Science.gov (United States)

    2010-07-01

    ... ammonium salt and polyalkyl, aminoalkyl meth-a-cryl-a-mide salt. 721.6540 Section 721.6540 Protection of... with tetraalkyl ammonium salt and polyalkyl, aminoalkyl meth-a-cryl-a-mide salt. (a) Chemical... as acrylamide, polymers with tetraalkyl ammonium salt and poly-al-kyl, amino alkyl...

  6. Studies on Biquaternary Ammonium Salt Algaecide for Removing Red Tide Algae

    Institute of Scientific and Technical Information of China (English)

    刘洁生; 张珩; 杨维东; 高洁; 柯琼

    2004-01-01

    The paper deals with the removal and control of red tide algae, Phaeoecystis globosa and Alexandrium tamarense by biquaternary ammonium salt algaecide. The results show that the efficient concentration of biquaternary ammonium salt to control the two algaes in 96 h is 0.8 mg · L-1 and 0.4 mg · L-1, respectively. It is found that biquaternary ammonium salt has high efficiency and longer duration of action in the removal and control of algae.Biquaternary ammonium salt might be an excellent algaecide to control HAB.

  7. Reversible hemostatic properties of sulfabetaine/quaternary ammonium modified hyperbranched polyglycerol.

    Science.gov (United States)

    Wen, Jiying; Weinhart, Marie; Lai, Benjamin; Kizhakkedathu, Jayachandran; Brooks, Donald E

    2016-04-01

    A library of hyperbranched polyglycerols (HPGs) functionalized with different mole fractions of zwitterionic sulfabetaine and cationic quaternary ammonium ligands was synthesized and characterized. A post-polymerization method was employed that utilized double bond moieties on the dendritic HPG for the coupling of thiol-terminated ligands via UV initiated thiol-ene "click" chemistry. The proportions of different ligands were precisely controlled by varying the ligand concentration during the irradiation process. The effect of the polymer library on hemostasis was investigated using whole human blood. It was found that polymer with ≥40% of alkenes converted to positive charges and the remainder to sulfabetaines caused hemagglutination at ≥1 mg/mL, without causing red blood cell lysis. The quaternary ammonium groups can interact with the negative charged sites on the membranes of erythrocytes, which provides the bioadhesion. The zwitterionic sulfabetaine evidently provides a hydration layer to partially mask the adverse effects that are likely to be caused by cationic moieties. The polymer was also found able to enhance platelet aggregation and activation in a concentration and positive charge density-dependent manner, which would contribute to initiating hemostasis. In a variety of other assays the material was found to be largely biocompatible. The polymer-induced hemostasis is obtained by a process independent of the normal blood clotting cascade but dependent on red blood cell agglutination, where the polymers promote hemostasis by linking erythrocytes together to form a lattice to entrap the cells.

  8. Random quaternary ammonium Diels-Alder poly(phenylene) copolymers for improved vanadium redox flow batteries

    Science.gov (United States)

    Largier, Timothy D.; Cornelius, Chris J.

    2017-06-01

    This study analyzes the effect of quaternary ammonium homopolymer (AmPP) and ionic and non-ionic random unit copolymerization (AmPP-PP) of Diels-Alder poly(phenylene)s on electrochemical and transport properties, vanadium redox flow battery performance, and material stability. AmPP-PP materials were synthesized with IEC's up to 2.2 meq/g, displaying a carbonate form ion conductivity of 17.3 mS/cm and water uptake of 57.3%. Vanadium ion permeability studies revealed that the random copolymers possess superior charge carrier selectivity. For materials of comparable ion content, at 10 mA/cm2 the random copolymer displayed a 14% increase in coulombic efficiency (CE) corresponding to a 7% increase in energy efficiency. All quaternary ammonium materials displayed ex situ degradation in a 0.5 M V5+ + 5 M H2SO4 solution, with the rate of degradation appearing to increase with IEC. Preliminary studies reveal that the neutralizing counter-ion has a significant effect on VRB performance, proportional to changes in vanadium ion molecular diffusion.

  9. Partial delignification of wood and membrane preparation using a quaternary ammonium ionic liquid

    Science.gov (United States)

    Miao, Jiaojiao; Yu, Yongqi; Jiang, Zeming; Tang, Lan; Zhang, Liping

    2017-01-01

    This work determined that southern yellow pine wood can almost be completely dissolved in the quaternary ammonium ionic liquid tetrabutylammonium acetate with dimethyl sulfoxide (in a 2:8 mass ratio), after minimal grinding, upon heating at 85 °C for three dissolution/reconstitution cycles, each 1.5 h. Approximately 34.6% of the native lignin and 67.4% of the native carbohydrates present in the original wood can subsequently be extracted, respectively, and were assessed. A gradual decrease in lignin with increased extraction cycles resulted in increased crystallinity index of the cellulose II in the cellulose-rich residue, as confirmed by X-ray diffraction. An increasingly homogeneous macrostructure in the cellulose-rich residue was also evident from scanning electron microscopy images. Membranes cast directly from either wood or cellulose-rich residue solutions in the same tetrabutylammonium acetate/dimethyl sulfoxide system, were prepared using a papermaking-like process. Morphological and mechanical studies indicated that lignin extraction made the membranes more uniform and flexible. Systematic increases in the fibril lengths and orientations of the recovered materials were also found with decreasing lignin contents on the basis of atomic force microscopy analysis. This work demonstrates that relatively efficient partial separation of pine wood and subsequent membrane preparation are possible using a quaternary ammonium ionic liquid. PMID:28266507

  10. Partial delignification of wood and membrane preparation using a quaternary ammonium ionic liquid

    Science.gov (United States)

    Miao, Jiaojiao; Yu, Yongqi; Jiang, Zeming; Tang, Lan; Zhang, Liping

    2017-03-01

    This work determined that southern yellow pine wood can almost be completely dissolved in the quaternary ammonium ionic liquid tetrabutylammonium acetate with dimethyl sulfoxide (in a 2:8 mass ratio), after minimal grinding, upon heating at 85 °C for three dissolution/reconstitution cycles, each 1.5 h. Approximately 34.6% of the native lignin and 67.4% of the native carbohydrates present in the original wood can subsequently be extracted, respectively, and were assessed. A gradual decrease in lignin with increased extraction cycles resulted in increased crystallinity index of the cellulose II in the cellulose-rich residue, as confirmed by X-ray diffraction. An increasingly homogeneous macrostructure in the cellulose-rich residue was also evident from scanning electron microscopy images. Membranes cast directly from either wood or cellulose-rich residue solutions in the same tetrabutylammonium acetate/dimethyl sulfoxide system, were prepared using a papermaking-like process. Morphological and mechanical studies indicated that lignin extraction made the membranes more uniform and flexible. Systematic increases in the fibril lengths and orientations of the recovered materials were also found with decreasing lignin contents on the basis of atomic force microscopy analysis. This work demonstrates that relatively efficient partial separation of pine wood and subsequent membrane preparation are possible using a quaternary ammonium ionic liquid.

  11. [Qualitative and quantitative analysis of ammonium salts of hexamethylenetetramine and 1,10-phenanthroline].

    Science.gov (United States)

    Bernatoniene, Rūta; Stankeviciene, Laimute; Stankevicius, Antanas; Janusiene, Laima

    2003-01-01

    By use of chemical and physicochemical methods the qualitative and quantitative analysis of bacteriostatic agents N-carbamoylmethylhexamethylenetetraamonium chloride (U-77) and 1-propyl-1,10-phenanthrolinium iodide (X-50) was carried out. The color reactions of these salts with various agents, e. g., concentrated acids, precipitants, oxidizers, indicators, ninhydrin, salts of heavy metals were assesssed. Some characteristic color reactions were found for analysis of quaternary ammonium salts. Experimental results indicate that interaction of N-carbamoylmethyhexamethylenetetraammonium chloride with silver nitrate leads to precipitate of the free silver in the form of a mirror under the proper conditions. It is a result of degradation of hexamethylenetetramine to formaldehyde and its oxidation, which is accompanied by reduction of silver ion to free silver. By use of thin-layer chromatography and ultraviolet spectrophotometry the physicochemical properties of compounds were tested. The suitability of qualitative methods, such as argentometry, mercurimetry, iodometry, extraction photometric analysis was detected. The results suggest, that the most suitable and precise method is argentometry.

  12. Effect of double quaternary ammonium groups on micelle formation of partially fluorinated surfactant.

    Science.gov (United States)

    Matsuoka, Keisuke; Chiba, Nagisa; Yoshimura, Tomokazu; Takeuchi, Emi

    2011-04-15

    To investigate the effect of divalency on the micelle properties, we synthesized divalent cationic surfactants composed of fluorocarbons and double quaternary ammonium groups N,N-dimethyl-N-[2-(N'-trimethylammonium)ethyl]-1-(3-perfluoroalkyl-2-hydroxypropyl) ammonium bromide [C(n)(F)C(3)-2Am; where n (=8 or 10) represents the number of carbon atoms in the fluorocarbon chain]. The double quaternary ammonium groups are continuously combined by the ethylene spacer in the surfactant head group, which clearly distinguishes the molecular design of the surfactant from those of the other typical divalent surfactants, bolaform and gemini types. The presence of the divalent head group results in an advantageous increase in their solubility [i.e., rise in the critical micelle concentration (cmc)]; however, the extra electrostatic repulsion between divalent cations decreases the surface activity in comparison with monovalent homologous fluorinated surfactants. The cmc, surface tension at cmc, and area occupied by a surfactant molecule in aqueous solution at 298.2K are 4.32 mM, 30.6 mN m(-1), and 0.648 nm(2 )molecule(-1), respectively, for C(8)(F)C(3)-2Am, and 1.51 mM, 30.4 mN m(-1), and 0.817 nm(2) molecule(-1), respectively, for C(10)(F)C(3)-2Am. The micellar size and shape were investigated by dynamic light scattering and freeze-fracture transmission electron microscopy (TEM). The TEM micrographs show that C(n)(F)C(3)-2Am (n=8 and 10) mainly forms ellipsoidal micelles approximately 10-100 nm in size for n=8 and approximately 10-20 nm in size for n=10. The degree of counterion binding to micelle was determined by selective electrode potential measurements, and the results of 0.7-0.8 agree with the average values for conventional monovalent ionic surfactants.

  13. Virucidal activity of a quaternary ammonium compound disinfectant against feline calicivirus: a surrogate for norovirus.

    Science.gov (United States)

    Jimenez, Luis; Chiang, Michael

    2006-06-01

    Norovirus, formerly known as Norwalk virus, is an important cause of gastroenteritis outbreaks in hospitals, food services, schools, and cruise ships. Infection control practices by using disinfectants to eliminate noroviruses from surfaces and environmental samples reduce the morbidity and spread of virus outbreaks. There are not many commercial disinfectants effective against norovirus. Noroviruses cannot be cultivated in vitro. However, feline calicivirus can be used as a surrogate to determine disinfectant efficacy against noroviruses. Feline calicivirus was used in a virucidal effectiveness test protocol as a surrogate for norovirus to determine the virucidal efficacy of R-82, a quaternary ammonium compound disinfectant cleaner. Feline calicivirus suspensions containing at least 5% fetal bovine serum were dried on carriers and treated with 1:256 dilutions of R-82 disinfectant in water, with a hardness of 400 ppm as calcium carbonate, for 10 minutes. Hypochlorite concentrations of 100 +/- 10 and 1,000 +/- 10 ppm, respectively, were also analyzed as internal control standards. After contact period, the test agents were neutralized with 2 mL of appropriate neutralizer, and mixtures were scraped from carrier surfaces with a cell scraper. Selected dilutions of the neutralized inoculum/test agent mixtures were added to cultured cell monolayers of appropriate host cells. Postincubation, the infectious feline calicivirus was scored microscopically by observing virus-specific cytopathic effects produced by replicating infectious virus. The performance criterion was a minimum of 4-log(10) reduction in cytopathic effects of feline calicivirus. After a 10-minute contact time, formulation R-82 diluted 1:256 showed a 6.6- and 6.4-log(10) reductions in cytopathic effects of feline calicivirus during initial and confirmatory testing, respectively, demonstrating complete inactivation of the virus. A hypochlorite solution of 1,000 ppm exhibited similar log(10) reductions to the

  14. Survival of adhering staphylococci during exposure to a quaternary ammonium compound evaluated by using atomic force microscopy imaging

    NARCIS (Netherlands)

    Crismaru, Mihaela; Asri, Lia ATW; Loontjens, Jacobus; Krom, Bastiaan P; de Vries, Jacob; van der Mei, Henderina; Busscher, Hendrik

    2011-01-01

    Effects of a quaternary ammonium compound (QAC) on the survival of adhering staphylococci on a surface were investigated using atomic force microscopy (AFM). Four strains with different minimal inhibitory concentrations (MIC) and minimal bactericidal concentrations (MBC) for the QAC were exposed to

  15. Defect passivation in hybrid perovskite solar cells using quaternary ammonium halide anions and cations

    Science.gov (United States)

    Zheng, Xiaopeng; Chen, Bo; Dai, Jun; Fang, Yanjun; Bai, Yang; Lin, Yuze; Wei, Haotong; Zeng, Xiao Cheng; Huang, Jinsong

    2017-07-01

    The ionic defects at the surfaces and grain boundaries of organic-inorganic halide perovskite films are detrimental to both the efficiency and stability of perovskite solar cells. Here, we show that quaternary ammonium halides can effectively passivate ionic defects in several different types of hybrid perovskite with their negative- and positive-charged components. The efficient defect passivation reduces the charge trap density and elongates the carrier recombination lifetime, which is supported by density-function-theory calculation. The defect passivation reduces the open-circuit-voltage deficit of the p-i-n-structured device to 0.39 V, and boosts the efficiency to a certified value of 20.59 ± 0.45%. Moreover, the defect healing also significantly enhances the stability of films in ambient conditions. Our findings provide an avenue for defect passivation to further improve both the efficiency and stability of solar cells.

  16. Preparation and Characterization of Montmorillonite Intercalation Compounds with Quaternary Ammonium Surfactant: Adsorption Effect of Zearalenone

    Directory of Open Access Journals (Sweden)

    Yujin Li

    2014-01-01

    Full Text Available Montmorillonite (Mt was used as the original material to prepare intercalation compounds with quaternary ammonium surfactant (QAS. The adsorption of zearalenone (ZEA onto Mt and organomodified Mt was investigated in vitro. Effects of QAS in binding ZEA were studied. By the method of intercalation with dioctadecylmethylbenzylammonium chloride (DOMBAC, the sample exhibited the highest adsorption rate of ZEA (93.2% which was much higher than that of Mt (10.5%. Several methods were adopted to characterize samples, including XRD, TG/DSC, N2 adsorption/desorption, and FTIR. Adsorption isotherm parameters were obtained from Langmuir and Freundlich and the adsorption data fitted better to Langmuir. All results indicate that organomodified Mt has great potential to be a high-performance material to control ZEA contamination.

  17. Quaternary ammonium silane-functionalized, methacrylate resin composition with antimicrobial activities and self-repair potential

    Science.gov (United States)

    Gong, Shi-qiang; Niu, Li-na; Kemp, Lisa K.; Yiu, Cynthia K.Y.; Ryou, Heonjune; Qi, Yi-pin; Blizzard, John D.; Nikonov, Sergey; Brackett, Martha G.; Messer, Regina L.W.; Wu, Christine D.; Mao, Jing; Brister, L. Bryan; Rueggeberg, Frederick A.; Arola, Dwayne D.; Pashley, David H.; Tay, Franklin R.

    2012-01-01

    Design of antimicrobial polymers for enhancing healthcare issues and minimizing environmental problems is an important endeavor with both fundamental and practical implications. Quaternary ammonium silane-functionalized methacrylate (QAMS) represents an example of antimicrobial macromonomers synthesized by a sol-gel chemical route; these compounds possess flexible Si-O-Si bonds. In present work, a partially-hydrolyzed QAMS copolymerized with bis-GMA is introduced. This methacrylate resin was shown to possess desirable mechanical properties with both a high degree of conversion and minimal polymerization shrinkage. Kill-on-contact microbiocidal activities of this resin were demonstrated using single-species biofilms of Streptococcus mutans (ATCC 36558), Actinomyces naeslundii (ATCC 12104) and Candida albicans (ATCC 90028). Improved mechanical properties after hydration provided the proof-of-concept that QAMS-incorporated resin exhibits self-repair potential via water-induced condensation of organic modified silicate (ormosil) phases within the polymerized resin matrix. PMID:22659173

  18. Determination of residues of quaternary ammonium disinfectants in food products by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    van Bruijnsvoort, Michel; Rooselaar, Joop; Stern, Alfred G; Jonker, Klaas M

    2004-01-01

    A liquid chromatography-tandem mass spectrometry method has been developed for the determination of residues of alkylbenzyldimethylammonium, didecyldimethylammonium, didodecyldimethylammonium, and benzyldodecylhydroxyethylammonium compounds in various food matrixes. These quaternary ammonium compounds (QAs) are used in the food industry as disinfectants. According to the Dutch Food Law, the total mass (expressed as cetyltrimethylammonium chloride) of QAs in food products shall not exceed the legislative limit of 0.5 mg/kg. Samples were extracted by a simple salting-out procedure, using acetonitrile and sodium chloride; about 100 samples could be prepared and analyzed daily. Special care had to be taken to thoroughly homogenize samples and to avoid the use of contaminated labware. The method was validated by a procedure in compliance with EU Directive 2002/657. From the matrixes of ice cream and minced meat, recoveries of more than 95% with a relative standard deviation of about 3% were obtained by 3 different analysts (n = 54). Detection limits were in the low microg/kg range. The decision limit (CCalpha) was determined to be 0.55 mg/kg. Dairy and meat products, collected in The Netherlands, were analyzed (761 samples). In 1% of the meat samples, 2% of the ice cream and milkshake samples, and 24% of the whipped cream samples, the Dutch legislative limit was exceeded. Over 2000 injections could be performed on a single column without deterioration of the peak shapes or recoveries.

  19. Ion-pair hollow-fiber liquid-phase microextraction of the quaternary ammonium surfactant dicocodimethylammonium chloride.

    Science.gov (United States)

    Hultgren, Sofie; Larsson, Niklas; Nilsson, Bo F; Jönsson, Jan Ake

    2009-02-01

    A two-phase hollow-fiber (HF) liquid-phase microextraction (LPME) method was developed for determination of a quaternary ammonium compound surfactant, dicocodimethylammonium chloride, in aqueous samples. The porous HF was fixed on a metal rod support and was impregnated with approximately 6.6 microL of organic extractant, which was immobilized in the HF pores. Surfactant extraction was facilitated by addition of carboxylic acid to the sample forming neutral ion pairs with the quaternary ammonium compound. After extraction, the analyte was transferred from the organic extractant in the fiber pores by dissolving the 1-octanol into 100 microL methanol. The methanol extract was analyzed by liquid chromatography-mass spectrometry. The method was optimized (with optimized parameters in brackets) with regard to type of organic extractant (1-octanol), fiber length (2 cm), choice and concentration of anionic carrier (600 microg L(-1) octanoate), procedure of transfer to methanol (15-min sonication), sample volume (250 mL), extraction time (17 h), pH (10), and ionic strength (50 mM carbonate). Aspects influencing repeatability in LPME of (quaternary ammonium) surfactants are discussed. The enrichment factor achieved in 250-mL carbonate buffer was around 400. Due to matrix effects, the enrichment factors achieved when industrial process water was analyzed were 120 or about 30% of that in carbonate buffer. Detection limits of 0.3 microg L(-1) in carbonate buffer and 0.9 microg L(-1) in industrial process water were obtained. If the studied compound is seen as a model substance representing quaternary dialkylated dimethylated ammonium surfactants in general, the developed method may be applied to other quaternary ammonium surfactants.

  20. Inhibition of biofouling by modification of forward osmosis membrane using quaternary ammonium cation.

    Science.gov (United States)

    Park, Kang-Hee; Yu, Sang-Hyun; Kim, Han-Shin; Park, Hee-Deung

    2015-01-01

    In the operation of the forward osmosis (FO) process, biofouling of the membrane is a potentially serious problem. Development of an FO membrane with antibacterial properties could contribute to a reduction in biofouling. In this study, quaternary ammonium cation (QAC), a widely used biocidal material, was conjugated with a silane coupling agent (3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride) and used to modify an FO membrane to confer antibacterial properties. Fourier transform infrared spectroscopy (FT-IR) demonstrated that the conjugated QAC was successfully immobilized on the FO membrane via covalent bonding. Bacterial viability on the QAC-modified membrane was confirmed via colony count method and visualized via bacterial viability assay. The QAC membrane decreased the viability of Escherichia coli to 62% and Staphylococcus aureus to 77% versus the control membrane. Inhibition of biofilm formation on the QAC modified membrane was confirmed via anti-biofilm tests using the drip-flow reactor and FO unit, resulting in 64% and 68% inhibition in the QAC-modified membrane against the control membrane, respectively. The results demonstrate the effectiveness of the modified membrane in reducing bacterial viability and inhibiting biofilm formation, indicating the potential of QAC-modified membranes to decrease operation costs incurred by biofouling.

  1. Determination of homologues of quaternary ammonium surfactants by capillary electrophoresis using indirect UV detection.

    Science.gov (United States)

    Liu, Hsueh-Ying; Ding, Wang-Hsien

    2004-02-06

    This investigation describes the simultaneous separation of two major non-chromophoric quaternary ammonium surfactants, alkyltrimethyl- and dialkyldimethylammonium compounds (ATMACs and DADMACs, respectively), by capillary electrophoresis (CE) using indirect UV detection. The most effective separation conditions was 10 mM phosphate buffer with 57.5% tetrahydrofuran and 3 mM sodium dodecyl sulfate (SDS) at pH 4.3, and the sample hydrodynamic injection of up to 20 s at 1 psi (approximately 60 nl), and an applied voltage of 25 kV (1 psi = 6.9 kPa). Specially, the selection of an appropriate chromophore and an internal standard (I.S.) to improve the peak identification and quantitation was systematically investigated. Decylbenzyldimethyl ammonium chloride (C10-BDMA+C-) as a chromophore with 3 mM sodium dodecyl sulfate provided the best detectability for all homologues. The reproducibility of the migration time and quantitative analysis can be improved by using tetraoctyl ammonium ion as an internal standard, giving the relative standard deviation (R.S.D.) less than 0.8% for the relative migration times, and 2.5-5.5% for the relative peak areas. A good linearity of CE analysis was obtained in the range of 1.0-20 microg/ml with r2 values of above 0.999. The analysis of cationic surfactants in commercial products of hair conditioners and fabric softeners was also performed. Electrospray mass spectrometric method was applied to evaluate the CE method, and the compatible results were obtained.

  2. 13C NMR and XPS characterization of anion adsorbent with quaternary ammonium groups prepared from rice straw, corn stalk and sugarcane bagasse

    Science.gov (United States)

    Cao, Wei; Wang, Zhenqian; Zeng, Qingling; Shen, Chunhua

    2016-12-01

    Despite amino groups modified crop straw has been intensively studied as new and low-cost adsorbent for removal of anionic species from water, there is still a lack of clear characterization for amino groups, especially quaternary ammonium groups in the surface of crop straw. In this study, we used 13C NMR and XPS technologies to characterize adsorbents with quaternary ammonium groups prepared from rice straw, corn stalk and sugarcane bagasse. 13C NMR spectra clearly showed the presence of quaternary ammonium groups in lignocelluloses structure of modified crop straw. The increase of nitrogen observed in XPS survey spectra also indicated the existence of quaternary ammonium group in the surface of the adsorbents. The curve fitting of high-resolution XPS N1s and C1s spectra were conducted to probe the composition of nitrogen and carbon contained groups, respectively. The results showed the proportion of quaternary ammonium group significantly increased in the prepared adsorbent's surface that was dominated by methyl/methylene, hydroxyl, quaternary ammonium, ether and carbonyl groups. This study proved that 13C NMR and XPS could be successfully utilized for characterization of quaternary ammonium modified crop straw adsorbents.

  3. Ambient and laboratory observations of organic ammonium salts in PM1.

    Science.gov (United States)

    Schlag, P; Rubach, F; Mentel, T F; Reimer, D; Canonaco, F; Henzing, J S; Moerman, M; Otjes, R; Prévôt, A S H; Rohrer, F; Rosati, B; Tillmann, R; Weingartner, E; Kiendler-Scharr, A

    2017-08-24

    Ambient measurements of PM1 aerosol chemical composition at Cabauw, the Netherlands, implicate higher ammonium concentrations than explained by the formation of inorganic ammonium salts. This additional particulate ammonium is called excess ammonium (eNH4). Height profiles over the Cabauw Experimental Site for Atmospheric Research (CESAR) tower, of combined ground based and airborne aerosol mass spectrometric (AMS) measurements on a Zeppelin airship show higher concentrations of eNH4 at higher altitudes compared to the ground. Through flights across the Netherlands, the Zeppelin based measurements furthermore substantiate eNH4 as a regional phenomenon in the planetary boundary layer. The excess ammonium correlates with mass spectral signatures of (di-)carboxylic acids, making a heterogeneous acid-base reaction the likely process of NH3 uptake. We show that this excess ammonium was neutralized by the organic fraction forming particulate organic ammonium salts. We discuss the significance of such organic ammonium salts for atmospheric aerosols and suggest that NH3 emission control will have benefits for particulate matter control beyond the reduction of inorganic ammonium salts.

  4. CHARACTERISTICS OF QUATERNARY AMMONIUM RESISTANT BACTERIA FROM A FINE PAPERMACHINE SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Hweig Wang; ChiYu Huang; ChunHan Ko

    2004-01-01

    To evaluate the biocide effect of quaternary ammonium chloride (QAC), a whitewater sample was taken from a fine papermachine headbox. By plate spreading method, 51 strains of facultative anaerobe were isolated morphologically. Then the strains were separately transferred to basal medium and were incubated before the beginning of log phase. To identify strains with different QAC resistance, 30-120 ppm of N-Alkyl-benzyl-dimethyl ammonium chloride were added to basal medium.Biocide effect was investigated by comparison of bacterial growth, which can be monitored by 600 nm light absorbance of basal medium suspension. Among 51 strains, only 2 strains can Survive for QAC concentration up to 120 ppm. API20E aud 16S rRNA gene sequencing technique were applied to identify two strains with highest (120 ppm)QAC resistance. One strain (HB22)was identified as Morganella morganii. HB22 can resist QAC concentration up to 150 ppm. HB22 is Gram-negative rod, motile with flagella, catalase positive, oxidase negative, Indole positive, H2S production negative, facultative anaerobe. HB22 has optimum growth condition of 35℃ and pH 7.0.HB22 can catabolize only glucose and D (+)-Mannose.The other (HB45) was identified with high similarity among Pseudomonas cf. monteili or Pseudomonas mosselii or Pseudomonas putida. HB45 can resist QAC concentration up to 200 ppm.HB45 is Gram-negative rod, motile with flagella,catalase positive, oxidase negative, Indole negative,H2S production negative, aerobe. HB45 has optimum growth condition of 30℃ and pH 7.4. HB45 can catabolize L-Arabinose, L(+)-Rhanmose, D (+)-Mannose, Glucose, Glycerol, Lactose, Maltose,Raffmose, Xylose, Cellulose and Xylan. The implication of this work to paper industry is also discussed.

  5. CHARACTERISTICS OF QUATERNARY AMMONIUM RESISTANT BACTERIA FROM A FINE PAPERMACHINE SYS-TEM

    Institute of Scientific and Technical Information of China (English)

    HweigWang; ChiYuHuang; ChunHanKo

    2004-01-01

    To evaluate the biocide effect of quaternary ammonium chloride (QAC), a whitewater sample wastaken from a fine papermachine headbox. By platespreading method, 51 strains of facultative anaerobewere isolated morphologically. Then the strains wereseparately transferred to basal medium and were incubated before the beginning of log phase. To identify strains with different QAC resistance, 30-120 ppmof N-Alkyl-benzyl-dimethyl ammonium chloridewere added to basal medium.Biocide effect was investigated by comparison of bacterial growth, whichcan be monitored by 600 nm light absorbance ofbasal medium suspension. Among 51 strains, only 2strains can Survive for QAC concentration up to 120ppm. API20E aud 16S rRNA gene sequencing technique were applied to identify two strains with highest (120 ppm)QAC resistance. One strain (HB22)was identified as Morganella morganii. HB22 can resist QAC concentration up to 150 ppm. HB22 isGram-negative rod, motile with flagella, catalasepositive, oxidase negative, Indole positive, H2S production negative, facultative anaerobe. HB22 has op-timum growth condition of 35C and pH 7.0.HB22can catabolize only glucose and D (+)-Mannose.The other (HB45) was identified with high similarityamong Pseudomonas cf. monteili or Pseudomonas mosselii or Pseudomonas putida. HB45can resist QAC concentration up to 200 ppm.HB45 is Gram-negative rod, motile with flagella,catalase positive, oxidase negative, Indole negative,H2S production negative, aerobe. HB45 has optimum growth condition of 30~C and pH 7.4. HB45can catabolize L-Arabinose, L (+)-Rhanmose, D(+)-Mannose, Glucose, Glycerol, Lactose, Maltose,Raffmose, Xylose, Cellulose and Xylan. The implication of this work to paper industry is also discussed.

  6. Superhydrophobic cotton fabric coating based on a complex layer of silica nanoparticles and perfluorooctylated quaternary ammonium silane coupling agent

    Science.gov (United States)

    Yu, Minghua; Gu, Guotuan; Meng, Wei-Dong; Qing, Feng-Ling

    2007-01-01

    A superhydrophobic complex coating for cotton fabrics based on silica nanoparticles and perfluorooctylated quaternary ammonium silane coupling agent (PFSC) was reported in this article. The complex thin film was prepared through a sol-gel process using cotton fabrics as a substrate. Silica nanoparticles in the coating made the textile surface much rougher, and perfluorooctylated quaternary ammonium silane coupling agent on the top layer of the surface lowered the surface free energy. Textiles coated with this coating showed excellent water repellent property, and water contact angle (CA) increased from 133° on cotton fabrics treated with pure PFSC without silica sol pretreatment up to 145°. The oil repellency was also improved and the contact angle of CH 2I 2 droplet on the fabric surface reached to 131°. In contrast, the contact angle of CH 2I 2 on the fabric surface treated with pure PFSC was only 125°.

  7. In-Water Treatment of Biofouling in Internal Systems: Field Validation of Quaternary Ammonium Compound (QAC) Chemical Treatment Protocols

    Science.gov (United States)

    2013-06-01

    joined the Environmental Research and Biotechnology Group in 2010. After completed his PhD in Marine Ecology and Ecotoxicology from the University of New...subsequent potential impacts on non- target marine organisms. QACs are not metabolized by aquatic organisms; they are accumulated in the consumable parts...Britton, D.K. and S. Dingman, Use of quaternary ammonium to control the spread of aquatic invasive species by wildland fire equipment Aquatic

  8. Antimicrobial activity of a quaternary ammonium methacryloxy silicate-containing acrylic resin: a randomised clinical trial

    Science.gov (United States)

    Liu, Si-ying; Tonggu, Lige; Niu, Li-na; Gong, Shi-qiang; Fan, Bing; Wang, Liguo; Zhao, Ji-hong; Huang, Cui; Pashley, David H.; Tay, Franklin R.

    2016-01-01

    Quaternary ammonium methacryloxy silicate (QAMS)-containing acrylic resin demonstrated contact-killing antimicrobial ability in vitro after three months of water storage. The objective of the present double-blind randomised clinical trial was to determine the in vivo antimicrobial efficacy of QAMS-containing orthodontic acrylic by using custom-made removable retainers that were worn intraorally by 32 human subjects to create 48-hour multi-species plaque biofilms, using a split-mouth study design. Two control QAMS-free acrylic disks were inserted into the wells on one side of an orthodontic retainer, and two experimental QAMS-containing acrylic disks were inserted into the wells on the other side of the same retainer. After 48 hours, the disks were retrieved and examined for microbial vitality using confocal laser scanning microscopy. No harm to the oral mucosa or systemic health occurred. In the absence of carry-across effect and allocation bias (disks inserted in the left or right side of retainer), significant difference was identified between the percentage kill in the biovolume of QAMS-free control disks (3.73 ± 2.11%) and QAMS-containing experimental disks (33.94 ± 23.88%) retrieved from the subjects (P ≤ 0.001). The results validated that the QAMS-containing acrylic exhibits favourable antimicrobial activity against plaque biofilms in vivo. The QAMS-containing acrylic may also be used for fabricating removable acrylic dentures. PMID:26903314

  9. Antibacterial Activity, in Vitro Cytotoxicity, and Cell Cycle Arrest of Gemini Quaternary Ammonium Surfactants.

    Science.gov (United States)

    Zhang, Shanshan; Ding, Shiping; Yu, Jing; Chen, Xuerui; Lei, Qunfang; Fang, Wenjun

    2015-11-10

    Twelve gemini quaternary ammonium surfactants have been employed to evaluate the antibacterial activity and in vitro cytotoxicity. The antibacterial effects of the gemini surfactants are performed on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) with minimum inhibitory concentrations (MIC) ranging from 2.8 to 167.7 μM. Scanning electron microscopy (SEM) analysis results show that these surfactants interact with the bacterial cell membrane, disrupt the integrity of the membrane, and consequently kill the bacteria. The data recorded on C6 glioma and HEK293 human kidney cell lines using an MTT assay exhibit low half inhibitory concentrations (IC50). The influences of the gemini surfactants on the cell morphology, the cell migration ability, and the cell cycle are observed through hematoxylin-eosin (HE) staining, cell wound healing assay, and flow cytometric analyses, respectively. Both the values of MIC and IC50 decrease against the growth of the alkyl chain length of the gemini surfactants with the same spacer group. In the case of surfactants 12-s-12, the MICs and IC50s are found to decrease slightly with the spacer chain length changing from 2 to 8 and again to increase at higher spacer length (s = 10-12). All of the gemini surfactants show great antibacterial activity and cytotoxicity, and they might exhibit potential applications in medical fields.

  10. Plasma-enhanced synthesis of bactericidal quaternary ammonium thin layers on stainless steel and cellulose surfaces.

    Science.gov (United States)

    Jampala, Soujanya N; Sarmadi, M; Somers, E B; Wong, A C L; Denes, F S

    2008-08-19

    We have investigated bottom-up chemical synthesis of quaternary ammonium (QA) groups exhibiting antibacterial properties on stainless steel (SS) and filter paper surfaces via nonequilibrium, low-pressure plasma-enhanced functionalization. Ethylenediamine (ED) plasma under suitable conditions generated films rich in secondary and tertiary amines. These functional structures were covalently attached to the SS surface by treating SS with O 2 and hexamethyldisiloxane plasma prior to ED plasma treatment. QA structures were formed by reaction of the plasma-deposited amines with hexyl bromide and subsequently with methyl iodide. Structural compositions were examined by electron spectroscopy for chemical analysis and Fourier transform infrared spectroscopy, and surface topography was investigated with atomic force microscopy and water contact angle measurements. Modified SS surfaces exhibited greater than a 99.9% decrease in Staphylococcus aureus counts and 98% in the case of Klebsiella pneumoniae. The porous filter paper surfaces with immobilized QA groups inactivated 98.7% and 96.8% of S. aureus and K. pneumoniae, respectively. This technique will open up a novel way for the synthesis of stable and very efficient bactericidal surfaces with potential applications in development of advanced medical devices and implants with antimicrobial surfaces.

  11. Sinorhizobium meliloti chemotaxis to quaternary ammonium compounds is mediated by the chemoreceptor McpX.

    Science.gov (United States)

    Webb, Benjamin A; Karl Compton, K; Castañeda Saldaña, Rafael; Arapov, Timofey D; Keith Ray, W; Helm, Richard F; Scharf, Birgit E

    2017-01-01

    The bacterium Sinorhizobium meliloti is attracted to seed exudates of its host plant alfalfa (Medicago sativa). Since quaternary ammonium compounds (QACs) are exuded by germinating seeds, we assayed chemotaxis of S. meliloti towards betonicine, choline, glycine betaine, stachydrine and trigonelline. The wild type displayed a positive response to all QACs. Using LC-MS, we determined that each germinating alfalfa seed exuded QACs in the nanogram range. Compared to the closely related nonhost species, spotted medic (Medicago arabica), unique profiles were released. Further assessments of single chemoreceptor deletion strains revealed that an mcpX deletion strain displayed little to no response to these compounds. Differential scanning fluorimetry showed interaction of the isolated periplasmic region of McpX (McpX(PR) and McpX34-306 ) with QACs. Isothermal titration calorimetry experiments revealed tight binding to McpX(PR) with dissociation constants (Kd ) in the nanomolar range for choline and glycine betaine, micromolar Kd for stachydrine and trigonelline and a Kd in the millimolar range for betonicine. Our discovery of S. meliloti chemotaxis to plant-derived QACs adds another role to this group of compounds, which are known to serve as nutrient sources, osmoprotectants and cell-to-cell signalling molecules. This is the first report of a chemoreceptor that mediates QACs taxis through direct binding.

  12. Novel Amino-Pyridine Functionalized Chitosan Quaternary Ammonium Derivatives: Design, Synthesis, and Antioxidant Activity.

    Science.gov (United States)

    Li, Qing; Zhang, Caili; Tan, Wenqiang; Gu, Guodong; Guo, Zhanyong

    2017-01-18

    Chemical modification of chitosan is increasingly studied for its potential of providing new applications of chitosan. Here, a group of novel chitosan quaternary ammonium derivatives containing pyridine or amino-pyridine were designed and successfully synthesized through chemical modification of chitosan. Pyridine and amino-pyridine were used as functional groups to improve the antifungal activity of chitosan derivatives. The chitosan derivatives' antioxidant activity against hydroxyl-radical and 1,1-Diphenyl-2-picrylhydrazyl (DPPH)-radical was tested in vitro. The results showed that chitosan derivatives had better water solubility and stronger antioxidant activity compared with chitosan in all assays. Especially, compounds 3C and 3E (with 3-amino pyridine and 2,3-diamino pyridine as substitute respectively) exhibited stronger hydroxyl-radical and DPPH-radical scavenging ability than other synthesized compounds. These data demonstrated that the synergistic effect of the amino group and pyridine would improve the antioxidant activity of chitosan derivatives, and the position of the amino group on pyridine could influence the antioxidant property of chitosan derivatives.

  13. Effect of Electrolyte Impurities within Starch on the Adhesion of Quaternary Ammonium Starch to Fibers

    Institute of Scientific and Technical Information of China (English)

    ZHU Zhi-feng; CHENG Zhe-qiong; GUO La-mei

    2008-01-01

    Influences of some electrolyte impurities within starch and starch cationization on the adhesion of quaternary ammonium cornstarch to cotton and polyester fibers were investigated. The electrolytes considered included NaCl, Na2SO44, NaH2PO4 and Na2HPO4. The adhesion to fibers was evaluated in terms of maximum strength "and work-to-break of the roving sized with the starch pastes containing electrolytes. It was found that the cationization showed a positive effect on the adhesion to both fibers whereas the electrolytes gave an adverse effect and reduced the adhesion. The adverse effect depends on the type and amount of electrolytes. The influence of electrolytes on the adhesion can be ranked in a series of NaH2 >PO4 > Na2 HPO4 > Na2SO4 > NaCl. The adhesion enhances as the modification extent increases and the electrolyte content decreases. Furthermore, the adverse effect can be compensated by the positive effect of the starch modification even at a low modification extent. If the electrolytes are fully eliminated, the cationic starch can increase the adhesion strength by more than 10% for both fibers.

  14. Alkaline stability of quaternary ammonium cations for alkaline fuel cell membranes and ionic liquids.

    Science.gov (United States)

    Marino, M G; Kreuer, K D

    2015-02-01

    The alkaline stability of 26 different quaternary ammonium groups (QA) is investigated for temperatures up to 160 °C and NaOH concentrations up to 10 mol L(-1) with the aim to provide a basis for the selection of functional groups for hydroxide exchange membranes in alkaline fuel cells and of ionic-liquid cations stable in basic conditions. Most QAs exhibit unexpectedly high alkaline stability with the exception of aromatic cations. β-Protons are found to be far less susceptible to nucleophilic attack than previously suggested, whereas the presence of benzyl groups, nearby hetero-atoms, or other electron-withdrawing species promote degradation reactions significantly. Cyclic QAs proved to be exceptionally stable, with the piperidine-based 6-azonia-spiro[5.5]undecane featuring the highest half-life at the chosen conditions. Absolute and relative stabilities presented herein stand in contrast to literature data, the differences being ascribed to solvent effects on degradation.

  15. Novel Amino-Pyridine Functionalized Chitosan Quaternary Ammonium Derivatives: Design, Synthesis, and Antioxidant Activity

    Directory of Open Access Journals (Sweden)

    Qing Li

    2017-01-01

    Full Text Available Chemical modification of chitosan is increasingly studied for its potential of providing new applications of chitosan. Here, a group of novel chitosan quaternary ammonium derivatives containing pyridine or amino-pyridine were designed and successfully synthesized through chemical modification of chitosan. Pyridine and amino-pyridine were used as functional groups to improve the antifungal activity of chitosan derivatives. The chitosan derivatives’ antioxidant activity against hydroxyl-radical and 1,1-Diphenyl-2-picrylhydrazyl (DPPH-radical was tested in vitro. The results showed that chitosan derivatives had better water solubility and stronger antioxidant activity compared with chitosan in all assays. Especially, compounds 3C and 3E (with 3-amino pyridine and 2,3-diamino pyridine as substitute respectively exhibited stronger hydroxyl-radical and DPPH-radical scavenging ability than other synthesized compounds. These data demonstrated that the synergistic effect of the amino group and pyridine would improve the antioxidant activity of chitosan derivatives, and the position of the amino group on pyridine could influence the antioxidant property of chitosan derivatives.

  16. Quaternary ammonium compounds (QACs): a review on occurrence, fate and toxicity in the environment.

    Science.gov (United States)

    Zhang, Chang; Cui, Fang; Zeng, Guang-ming; Jiang, Min; Yang, Zhong-zhu; Yu, Zhi-gang; Zhu, Meng-ying; Shen, Liu-qing

    2015-06-15

    Quaternary ammonium compounds (QACs) are widely applied in household and industrial products. Most uses of QACs can be expected to lead to their release to wastewater treatment plants (WWTPs) and then dispersed into various environmental compartments through sewage effluent and sludge land application. Although QACs are considered to be aerobically biodegradable, the degradation is affected by its chemical structures, dissolved oxygen concentration, complexing with anionic surfactants, etc. High abundance of QACs has been detected in sediment and sludge samples due to its strong sorption and resistance to biodegradation under anoxic/anaerobic conditions. QACs are toxic to a lot of aquatic organisms including fish, daphnids, algae, rotifer and microorganisms employed in wastewater treatment systems. And antibiotic resistance has emerged in microorganisms due to excessive use of QACs in household and industrial applications. The occurrence of QACs in the environment is correlated with anthropogenic activities, such as wastewater discharge from WWTPs or single source polluters, and sludge land application. This article also reviews the analytical methods for determination of QACs in environmental compartments including surface water, wastewater, sewage sludge and sediments. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. An operationally flexible fuel cell based on quaternary ammonium-biphosphate ion pairs

    Science.gov (United States)

    Lee, Kwan-Soo; Spendelow, Jacob S.; Choe, Yoong-Kee; Fujimoto, Cy; Kim, Yu Seung

    2016-09-01

    Fuel cells are promising devices for clean power generation in a variety of economically and environmentally significant applications. Low-temperature proton exchange membrane (PEM) fuel cells utilizing Nafion require a high level of hydration, which limits the operating temperature to less than 100 ∘C. In contrast, high-temperature PEM fuel cells utilizing phosphoric acid-doped polybenzimidazole can operate effectively up to 180 ∘C however, these devices degrade when exposed to water below 140 ∘C. Here we present a different class of PEM fuel cells based on quaternary ammonium-biphosphate ion pairs that can operate under conditions unattainable with existing fuel cell technologies. These fuel cells exhibit stable performance at 80-160 ∘C with a conductivity decay rate more than three orders of magnitude lower than that of a commercial high-temperature PEM fuel cell. By increasing the operational flexibility, this class of fuel cell can simplify the requirements for heat and water management, and potentially reduce the costs associated with the existing fully functional fuel cell systems.

  18. Anti-Caries Effects of Dental Adhesives Containing Quaternary Ammonium Methacrylates with Different Chain Lengths

    Directory of Open Access Journals (Sweden)

    Qi Han

    2017-06-01

    Full Text Available The objectives of this study were to investigate the effects of dental adhesives containing quaternary ammonium methacrylates (QAMs with different alkyl chain lengths (CL on ecological caries prevention in vitro. Five QAMs were synthesized with a CL = 3, 6, 9, 12, and 16 and incorporated into adhesives. Micro-tensile bond strength and surface charge density were used to measure the physical properties of the adhesives. The proportion change in three-species biofilms consisting of Streptococcus mutans, Streptococcus sanguinis, and Streptococcus gordonii was tested using the TaqMan real-time polymerase chain reaction. Lactic acid assay, MTT [3-(4,5-dimethyl-thiazol-2-yl-2,5-diphenyltetrazolium bromide] assay, exopolysaccharide staining, live/dead staining, scanning electron microscopy (SEM, and transverse microradiography (TMR were performed to study the anti-biofilm and anti-demineralization effects of the dental adhesives. The results showed that incorporating QAMs with different alkyl chain lengths into the adhesives had no obvious effect on the dentin bond strength. The adhesives containing QAMs with a longer alkyl chain developed healthier biofilms. The surface charge density, anti-biofilm, and anti-demineralization effects of the adhesives increased with a CL of the QAMs from 3 to 12, but decreased slightly with a CL from 12 to 16. In conclusion, adhesives containing QAMs with a tailored chain length are promising for preventing secondary caries in an “ecological way”.

  19. Characterization of sodium bentonites: effect of treatment with ammonium salt- free organic surfactant; Caracterizacao de bentonitas sodicas: efeito do tratamento com surfactante organico livre de sal de amonio

    Energy Technology Data Exchange (ETDEWEB)

    Morita, R. Y.; Barbosa, R. V.; Kloss, J.R., E-mail: julianaweber@utfpr.edu.br [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil). Dartamento de Quimica e Biologia

    2015-07-15

    Bentonite, which the main clay mineral is montmorillonite, are commercially attractive because of its abundance in nature. The clays can be modified by ion exchange reactions of ions contained in the interlayer region with cationic surfactants that include ammonium or phosphonium salts. The clays origin and the type of surfactants (modifiers) are the main factors in the alteration of physical and chemical properties of these materials. This study aims to characterize and compare the results of natural bentonite commercially available and the effect of treatments with quaternary ammonium salt and an organic compound free of ammonium salt. The FTIR and XRD results indicate the process of organophilization of clays after treatment with the surfactants. These treatments have altered the average particle size, suggesting the formation of agglomerates, which was showed in the SEM images. The results of surface area and particle size data indicated the presence of larger particles. Although the two surfactants have shown similarities in the investigated properties, the organoclays free of ammonium salt are more promising in terms of its use as well as for their preparation and solubility. (author)

  20. Formation and transformation of metastable double salts from the crystallization of mixed ammonium nitrate and ammonium sulfate particles.

    Science.gov (United States)

    Ling, Tsz Yan; Chan, Chak K

    2007-12-01

    Ammonium nitrate (AN) and ammonium sulfate (AS) are ubiquitous components of atmospheric aerosols. Thermodynamic models predict formation of pure (AN and AS) and double salts (3AN. AS and 2AN. AS) for the AN/AS system. Because of the high supersaturation at which a droplet crystallizes, metastable crystal formation is possible. In this study, the identity of the crystals formed from the crystallization of equimolar AN/AS mixed droplets was investigated in an electrodynamic balance coupled with a Raman spectroscopic system. Raman spectra of bulk AN/AS double salts possibly formed in this system are first reported for comparison with the single particle Raman results. The double-salt 3AN. AS, not predicted from thermodynamics, was observed in the freshly crystallized single particles. The degree of metastability can be different among several crystallization processes of the same particles. The metastable salt 3AN. AS gradually transformed into stable 2AN. AS, and the rate of such transformation increased with increasing relative humidity. This study illustrates the possibility of occurrence of metastable salts in atmospheric aerosols.

  1. Molecular dynamics simulation of secondary sorption behavior of montmorillonite modified by single chain quaternary ammonium cations.

    Science.gov (United States)

    Zhao, Qian; Burns, Susan E

    2012-04-03

    Organoclays synthesized from single chain quaternary ammonium cations (QAC) ((CH(3))(3)NR(+)) exhibit different mechanisms for the sorption of nonpolar organic compounds as the length of the carbon chain is increased. The interaction between a nonpolar sorbate and an organoclay intercalated with small QACs has been demonstrated to be surface adsorption, while partitioning is the dominant mechanism in clays intercalated with long chain surfactants. This study presents the results of a molecular dynamics (MD) simulation performed to examine the sorption mechanisms of benzene in the interlayer of three organoclays with chain lengths ranging from 1 to 16 carbons: tetramethylammonium (TMA) clay; decyltrimethylammonium (DTMA) clay; and hexadecyltrimethylammonium (HDTMA) clay. The basis of the overall simulation was a combined force field of ClayFF and CVFF. In the simulations, organic cations were intercalated and benzene molecules were introduced to the interlayer, followed by whole system NPT and NVT time integration. Trajectories of all the species were recorded after the system reached equilibrium and subsequently analyzed. Simulation results confirmed that the arrangement of the surfactants controlled the sorption mechanism of organoclays. Benzene molecules were observed to interact directly with the clay surface in the presence of TMA cations, but tended to interact with the aliphatic chain of the HDTMA cation in the interlayer. The simulation provided insight into the nature of the adsorption/partitioning mechanisms in organoclays, and explained experimental observations of decreased versus increased uptake capacities as a function of increasing total organic carbon (TOC) for TMA clay and HDTMA clay, respectively. The transition of sorption mechanisms was also quantified with simulation of DTMA clay, with a chain length between that of TMA and HDTMA. Furthermore, this study suggested that at the molecular level, the controlling factor for the ultimate sorption

  2. Tolerance to quaternary ammonium compound disinfectants may enhance growth of Listeria monocytogenes in the food industry.

    Science.gov (United States)

    Møretrø, Trond; Schirmer, Bjørn C T; Heir, Even; Fagerlund, Annette; Hjemli, Pernille; Langsrud, Solveig

    2017-01-16

    The antibacterial effect of disinfectants is crucial for the control of Listeria monocytogenes in food processing environments. Tolerance of L. monocytogenes to sublethal levels of disinfectants based on quaternary ammonium compounds (QAC) is conferred by the resistance determinants qacH and bcrABC. The presence and distribution of these genes have been anticipated to have a role in the survival and growth of L. monocytogenes in food processing environments where QAC based disinfectants are in common use. In this study, a panel of 680 L. monocytogenes from nine Norwegian meat- and salmon processing plants were grouped into 36 MLVA profiles. The presence of qacH and bcrABC was determined in 101 isolates from the 26 most common MLVA profiles. Five MLVA profiles contained qacH and two contained bcrABC. Isolates with qacH and bcrABC showed increased tolerance to the QAC Benzalkonium chloride (BC), with minimal inhibitory concentrations (MICs) of 5-12, 10-13 and monocytogenes when the sample BC levels were high (>100ppm). A sample with lower BC concentrations (14ppm of chain length C-12 and 2.7ppm of chain length C-14) inhibited growth of L. monocytogenes not containing bcrABC or qacH, compared to strains with these genes. The study has shown that L. monocytogenes harbouring the QAC resistance genes qacH and bcrABC are prevalent in the food industry and that residuals of QAC may be present in concentrations after sanitation in the industry that result in a growth advantage for bacteria with such resistance genes. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  3. Copper and quaternary ammonium cations exert synergistic bactericidal and antibiofilm activity against Pseudomonas aeruginosa.

    Science.gov (United States)

    Harrison, Joe J; Turner, Raymond J; Joo, Daniel A; Stan, Michelle A; Chan, Catherine S; Allan, Nick D; Vrionis, Helen A; Olson, Merle E; Ceri, Howard

    2008-08-01

    Biofilms are slimy aggregates of microbes that are likely responsible for many chronic infections as well as for contamination of clinical and industrial environments. Pseudomonas aeruginosa is a prevalent hospital pathogen that is well known for its ability to form biofilms that are recalcitrant to many different antimicrobial treatments. We have devised a high-throughput method for testing combinations of antimicrobials for synergistic activity against biofilms, including those formed by P. aeruginosa. This approach was used to look for changes in biofilm susceptibility to various biocides when these agents were combined with metal ions. This process identified that Cu(2+) works synergistically with quaternary ammonium compounds (QACs; specifically benzalkonium chloride, cetalkonium chloride, cetylpyridinium chloride, myristalkonium chloride, and Polycide) to kill P. aeruginosa biofilms. In some cases, adding Cu(2+) to QACs resulted in a 128-fold decrease in the biofilm minimum bactericidal concentration compared to that for single-agent treatments. In combination, these agents retained broad-spectrum antimicrobial activity that also eradicated biofilms of Escherichia coli, Staphylococcus aureus, Salmonella enterica serovar Cholerasuis, and Pseudomonas fluorescens. To investigate the mechanism of action, isothermal titration calorimetry was used to show that Cu(2+) and QACs do not interact in aqueous solutions, suggesting that each agent exerts microbiological toxicity through independent biochemical routes. Additionally, Cu(2+) and QACs, both alone and in combination, reduced the activity of nitrate reductases, which are enzymes that are important for normal biofilm growth. Collectively, the results of this study indicate that Cu(2+) and QACs are effective combinations of antimicrobials that may be used to kill bacterial biofilms.

  4. Copper and Quaternary Ammonium Cations Exert Synergistic Bactericidal and Antibiofilm Activity against Pseudomonas aeruginosa▿

    Science.gov (United States)

    Harrison, Joe J.; Turner, Raymond J.; Joo, Daniel A.; Stan, Michelle A.; Chan, Catherine S.; Allan, Nick D.; Vrionis, Helen A.; Olson, Merle E.; Ceri, Howard

    2008-01-01

    Biofilms are slimy aggregates of microbes that are likely responsible for many chronic infections as well as for contamination of clinical and industrial environments. Pseudomonas aeruginosa is a prevalent hospital pathogen that is well known for its ability to form biofilms that are recalcitrant to many different antimicrobial treatments. We have devised a high-throughput method for testing combinations of antimicrobials for synergistic activity against biofilms, including those formed by P. aeruginosa. This approach was used to look for changes in biofilm susceptibility to various biocides when these agents were combined with metal ions. This process identified that Cu2+ works synergistically with quaternary ammonium compounds (QACs; specifically benzalkonium chloride, cetalkonium chloride, cetylpyridinium chloride, myristalkonium chloride, and Polycide) to kill P. aeruginosa biofilms. In some cases, adding Cu2+ to QACs resulted in a 128-fold decrease in the biofilm minimum bactericidal concentration compared to that for single-agent treatments. In combination, these agents retained broad-spectrum antimicrobial activity that also eradicated biofilms of Escherichia coli, Staphylococcus aureus, Salmonella enterica serovar Cholerasuis, and Pseudomonas fluorescens. To investigate the mechanism of action, isothermal titration calorimetry was used to show that Cu2+ and QACs do not interact in aqueous solutions, suggesting that each agent exerts microbiological toxicity through independent biochemical routes. Additionally, Cu2+ and QACs, both alone and in combination, reduced the activity of nitrate reductases, which are enzymes that are important for normal biofilm growth. Collectively, the results of this study indicate that Cu2+ and QACs are effective combinations of antimicrobials that may be used to kill bacterial biofilms. PMID:18519726

  5. The selectivity of different external binding sites for quaternary ammonium ions in cloned potassium channels.

    Science.gov (United States)

    Jarolimek, W; Soman, K V; Brown, A M; Alam, M

    1995-09-01

    Tetraethylammonium (TEA) is thought to be the most effective quaternary ammonium (QA) ion blocker at the external site of K+ channels, and small changes to the TEA ion reduce its potency. To examine the properties of the external QA receptor, we applied a variety of QA ions to excised patches from human embryonic kidney cells or Xenopus oocytes transfected with the delayed rectifying K+ channels Kv 2.1 and Kv 3.1. In outside-out patches of Kv 3.1, the relative potencies were TEA > tetrapropylammonium (TPA) > tetrabutylammonium (TBA). In contrast to Kv 3.1, the relative potencies in Kv 2.1 were TBA > TEA > TPA. In Kv 3.1 and Kv 2.1, external tetrapentylammonium (TPeA) blocked K+ currents in a fast, reversible and, in contrast to TEA, time-dependent manner. The external binding of TPeA appeared to be voltage independent, unlike the effects of TPeA applied to inside-out patches. External n-alkyl-triethylammonium compounds (C8, C10 chain length) had a lower affinity than TEA in Kv 3.1, but a higher affinity than TEA in Kv 2.1. In Kv 3.1, the decrease in QA affinity was large when one or two methyl groups were substituted for ethyl groups in TEA, but minor when propyl groups replaced ethyl groups. Changes in the free energy of binding could be correlated to changes in the free energy of hydration of TEA derivatives calculated by continuum methodology. These results reveal a substantial hydrophobic component of external QA ion binding to Kv 2.1, and to a lesser degree to Kv 3.1, in addition to the generally accepted electrostatic interactions. The chain length of hydrophobic TEA derivatives affects the affinity for the hydrophobic binding site, whereas the hydropathy of QA ions determines the electrostatic interaction energy.

  6. Synthesis and structure-activity study of quaternary ammonium functionalized beta-cyclodextrin-carboxymethylcellulose polymers.

    Science.gov (United States)

    Bonenfant, Danielle; Bourgeois, François-René; Mimeault, Murielle; Monette, Frédéric; Niquette, Patrick; Hausler, Robert

    2011-01-01

    Carboxymethylcellulose (CMC) and beta-cyclodextrin (beta-CD)-based polymers functionalized with two types of quaternary ammonium compounds (QACs), the alkaquat DMB-451 (N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride) (DMD-451) named polymer DMB-451, and FMB 1210-8 (a blend of 32 w% N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride and 48 w% of didecyldimethylammonium chloride) named polymer FMB 1210-8, were synthethized and characterized by Fourier transform infrared spectroscopy. The antimicrobial activities of these polymers against Eschericia coli were also evaluated at 25 degrees C in wastewater. The results have indicated that the polymer FMB 1210-8 possesses a high-affinity binding with bacterial cells that induces a rapid disinfection process. Moreover, in the same experimental conditions of disinfection (mixture of 1.0 g of polymer and 100 mL of wastewater), the polymer FMB 1210-8 has a higher antimicrobial efficiency (99.90%) than polymer DMB-451 (92.8%). This phenomenon might be associated to a stronger interaction with bacterial cells due to stronger binding affinity for E. coli cells and greater killing efficiency of the C10 alkyl chains QAC of polymer FMB 1210-8 to disrupt the bacterial cell membrane as compared to N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride. Together, these results suggest that the polymer FMB 1210-8 could constitute a good disinfectant against Escherichia coli, which could be advantageously used in wastewater treatments due to the low toxicity of beta-CD and CMC, and moderated toxicity of FMB 1210-8 to human and environment.

  7. Experimental investigation and DFT calculation of different amine/ammonium salts adsorption on kaolinite

    Science.gov (United States)

    Chen, Jun; Min, Fan-fei; Liu, Lingyun; Liu, Chunfu; Lu, Fangqin

    2017-10-01

    The adsorption of four different amine/ammonium salts of DDA (Dodecyl amine), MDA (N-methyldodecyl amine), DMDA (N,N-dimethyldodecyl amine) and DTAC (Dodecyl trimethyl ammonium chloride) on kaolinite particles was investigated in the study through the measurement of contact angles, zeta potentials, aggregation observation, adsorption and sedimentation. The results show that different amine/ammonium salts can adsorb on the kaolinite surface to enhance the hydrophobicity and reduce the electronegativity of kaolinite particle surface, and thus induce a strong hydrophobic aggregation of kaolinite particles which promotes the settlement of kaolinite. To explore the adsorption mechanism of these four amine/ammonium salts on kaolinite surfaces, the adsorptions of DDA+, MDA+, DMDA+ and DTAC+ on kaolinite (001) surface and (00 1 bar) surface are calculated with DFT (Density functional theory). The DFT calculation results indicate that different amine/ammonium cations can strongly adsorbed on kaolinite (001) surface and (00 1 bar) surface by forming Nsbnd H⋯O strong hydrogen bonds or Csbnd H⋯O weak hydrogen bonds, and there are strongly electrostatic attractions between different amine/ammonium cations and kaolinite surfaces. The main adsorption mechanism of amine/ammonium cations on kaolinite is hydrogen-bond interaction and electrostatic attraction.

  8. Biodegradability and aquatic toxicity of quaternary ammonium-based gemini surfactants: Effect of the spacer on their ecological properties.

    Science.gov (United States)

    Garcia, M Teresa; Kaczerewska, Olga; Ribosa, Isabel; Brycki, Bogumił; Materna, Paulina; Drgas, Małgorzata

    2016-07-01

    Aerobic biodegradability and aquatic toxicity of five types of quaternary ammonium-based gemini surfactants have been examined. The effect of the spacer structure and the head group polarity on the ecological properties of a series of dimeric dodecyl ammonium surfactants has been investigated. Standard tests for ready biodegradability assessment (OECD 310) were conducted for C12 alkyl chain gemini surfactants containing oxygen, nitrogen or a benzene ring in the spacer linkage and/or a hydroxyethyl group attached to the nitrogen atom of the head groups. According to the results obtained, the gemini surfactants examined cannot be considered as readily biodegradable compounds. The negligible biotransformation of the gemini surfactants under the standard biodegradation test conditions was found to be due to their toxic effects on the microbial population responsible for aerobic biodegradation. Aquatic toxicity of gemini surfactants was evaluated against Daphnia magna. The acute toxicity values to Daphnia magna, IC50 at 48 h exposure, ranged from 0.6 to 1 mg/L. On the basis of these values, the gemini surfactants tested should be classified as toxic or very toxic to the aquatic environment. However, the dimeric quaternary ammonium-based surfactants examined result to be less toxic than their corresponding monomeric analogs. Nevertheless the aquatic toxicity of these gemini surfactants can be reduced by increasing the molecule hydrophilicity by adding a heteroatom to the spacer or a hydroxyethyl group to the polar head groups.

  9. The modifition of hyperbranched polymers with quaternary ammonium salt and its application on kapok fiber reactive dyeing%超支化聚合物的季铵盐修饰及其在木棉纤维活性染料染色中的应用

    Institute of Scientific and Technical Information of China (English)

    丁颖; 高群艳; 张召阳; 蔡再生; 徐丽慧; 沈勇

    2016-01-01

    The water soluble amino-terminated hyperbranched polymer (HBP-NH2) was synthesized with Methacrylate and Diethylenetriamine. Then the quaternary ammonium hyperbranched polymers (HBP-HDC) was prepared with self-made cationic modification and hyperbranched polymers. The Infrared spectroscopy analysis confirmed the synthesis of HBP-NH2and the NMR spectrum analysis confirmed that cationic modification was successfully grafted onto HBP-NH2. The Modification process of kapok fiber with HBP-HDC is as following: the composition ratio of cationic modification and hyperbranched polymer 4∶1, HBP-HDC concentration 4 g/L, modification temperature 50 ℃, bath ratio1∶100, pH=9 and modification time 30 min. After the modification, the dyed fabric showed obvious improvement on the dyeing properties compared to the control one, with the dye uptake 98%, fixation rate 78%, K/Svalue 7.98 and washing fastness 4~5 grades.%以丙烯酸甲酯和二乙烯三胺为原料,合成了水溶性端氨基超支化聚合物(HBP-NH2),并将其与自制的阳离子改性剂接枝合成了季铵盐超支化聚合物(HBP-HDC)。通过红外分光光度计对产品进行了表征,确证了HBP-NH2的制备成功;通过核磁共振谱图确证了HBP-NH2与阳离子改性剂接枝成功。HBP-HDC改性木棉纤维的工艺:阳离子改性剂与超支化聚合物的合成比为4∶1;HBP-HDC的质量浓度为4 g/L,温度50℃,浴比1∶100,改性液pH=9,改性时间30 min。活性染料Novacron RED FN-R在改性后木棉纤维上的上染率约98%,固色率约78%,K/S值为7.98,耐水洗色牢度4~5级,均较未改性木棉有较大的提高。

  10. Enhanced Selectivity of the Separation of CO2 from N2 during Crystallization of Semi-Clathrates from Quaternary Ammonium Solutions

    Directory of Open Access Journals (Sweden)

    Herri J.-M.

    2014-09-01

    Full Text Available CO2 mitigation is crucial environmental problem and a societal challenge for this century. CO2 capture and sequestration is a route to solve a part of the problem, especially for the industries in which the gases to be treated are well localized. CO2 capture by using hydrate is a process in which the cost of the separation is due to compression of gases to reach the gas hydrate formation conditions. Under pressure, the water and gas forms a solid that encapsulates preferentially CO2. The gas hydrate formation requires high pressures and low temperatures, which explains the use of thermodynamic promoters to decrease the operative pressure. Quaternary ammoniums salts represent an interesting family of components because of their thermodynamic effect, but also because they can generate crystals that are easily handled. In this work, we have made experiments concerning the equilibrium of (CO2, N2 in presence of Tetra-n-Butyl Ammonium Bromide (TBAB which form a semi-clathrate hydrate. We propose equilibrium data (pressure, temperature in presence of TBAB at different concentrations and we compare them to the literature. We have also measured the composition of the hydrate phase in equilibrium with the gas phase at different CO2 concentrations. We observe that the selectivity of the separation is dramatically increased in comparison to the selectivity of the pure water gas clathrate hydrate. We observe also a benefice on the operative pressure which can be dropped down to the atmospheric pressure.

  11. The potential/pH diagram of silver in aqueous ammonium salt solution

    NARCIS (Netherlands)

    Sluyters, J.H.; Wijnen, M.D.; Hul, H.J. van den

    1961-01-01

    The potential/pH diagram of silver in aqueous ammonium salt solution at 25°C has been calculated and verified experimentally. Calculations were carried out on the basis of the standard potential of the silver/silver-ion couple, the dissociation constants of the silver mono- and di-ammonia

  12. Detection of singly- and doubly-charged quaternary ammonium drugs in equine urine by liquid chromatography/tandem mass spectrometry.

    Science.gov (United States)

    Ho, Emmie N M; Kwok, W H; Wong, April S Y; Wan, Terence S M

    2012-01-13

    Quaternary ammonium drugs (QADs) are anticholinergic agents some of which are known to have been abused or misused in equine sports. A recent review of literature shows that the screening methods reported thus far for QADs mainly cover singly-charged QADs. Doubly-charged QADs are extremely polar substances which are difficult to be extracted and poorly retained on reversed-phase columns. It would be ideal if a comprehensive method can be developed which can detect both singly- and doubly-charged QADs. This paper describes an efficient liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for the simultaneous detection and confirmation of 38 singly- and doubly-charged QADs at sub-parts-per-billion (ppb) to low-ppb levels in equine urine after solid-phase extraction. Quaternary ammonium drugs were extracted from equine urine by solid-phase extraction (SPE) using an ISOLUTE(®) CBA SPE column and analysed by LC/MS/MS in the positive electrospray ionisation mode. Separation of the 38 QADs was achieved on a polar group embedded C18 LC column with a mixture of aqueous ammonium formate (pH 3.0, 10 mM) and acetonitrile as the mobile phase. Detection and confirmation of the 38 QADs at sub-ppb to low-ppb levels in equine urine could be achieved within 16 min using selected reaction monitoring (SRM). Matrix interference of the target transitions at the expected retention times was not observed. Other method validation data, including precision and recovery, were acceptable. The method was successfully applied to the analyses of drug-administration samples.

  13. 40 CFR 180.1284 - Ammonium salts of higher fatty acids (C8-C18 saturated; C8-C12 unsaturated); exemption from the...

    Science.gov (United States)

    2010-07-01

    ... Ammonium salts of higher fatty acids (C8-C18 saturated; C8-C12 unsaturated); exemption from the requirement of a tolerance. Ammonium salts of C8-C18 saturated and C8-C12 unsaturated higher fatty acids are... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Ammonium salts of higher fatty...

  14. Review and phylogenetic analysis of qac genes that reduce susceptibility to quaternary ammonium compounds in Staphylococcus species

    DEFF Research Database (Denmark)

    Wassenaar, Trudy M; Ussery, David; Nielsen, Lene Nørby;

    2015-01-01

    The qac genes of Staphylococcus species encode multidrug efflux pumps: membrane proteins that export toxic molecules and thus increase tolerance to a variety of compounds such as disinfecting agents, including quaternary ammonium compounds (for which they are named), intercalating dyes and some...... described in the literature for qac detection may miss particular qac genes due to lack of DNA conservation. Despite their resemblance in substrate specificity, the Qac proteins belonging to the two protein families have little in common. QacA and QacB are highly conserved in Staphylococcus species, while...... variation, despite their short length, even within the Staphylococcus genus. Phylogenetic analysis of these genes identified similarity to a large number of other SMR members, found in staphylococci as well as in other genera. A number of phylogenetic trees of SMR Qac proteins are presented here, starting...

  15. QSAR study on maximal inhibition (Imax) of quaternary ammonium antagonists for S-(-)-nicotine-evoked dopamine release from dopaminergic nerve terminals in rat striatum.

    Science.gov (United States)

    Zheng, Fang; McConnell, Matthew J; Zhan, Chang-Guo; Dwoskin, Linda P; Crooks, Peter A

    2009-07-01

    Maximal inhibition (I(max)) of the agonist effect is an important pharmacological property of inhibitors that interact with multiple receptor subtypes that are activated by the same agonist and which elicit the same functional response. This report represents the first QSAR study on a set of 66 mono- and bis-quaternary ammonium salts that act as antagonists at neuronal nicotinic acetylcholine receptors mediating nicotine-evoked dopamine release, conducted using multi-linear regression (MLR) and neural network (NN) analysis with the maximal inhibition (I(max)) values of the antagonists as target values. The statistical results for the generated MLR model were: r(2)=0.89, rmsd=9.01, q(2)=0.83 and loormsd=11.1; the statistical results for the generated NN model were: r(2)=0.89, rmsd=8.98, q(2)=0.83 and loormsd=11.2. The maximal inhibition values of the compounds exhibited a good correlation with the predictions made by the QSAR models developed, which provide a basis for rationalizing selection of compounds for synthesis in the discovery of effective and selective second generation inhibitors of nAChRs mediating nicotine-evoked dopamine release.

  16. Quaternary ammonium-functionalized silica sorbents for the solid-phase extraction of aromatic amines under normal phase conditions.

    Science.gov (United States)

    Vidal, Lorena; Robin, Orlane; Parshintsev, Jevgeni; Mikkola, Jyri-Pekka; Riekkola, Marja-Liisa

    2013-04-12

    Quaternary ammonium-functionalized silica materials were synthesized and applied for solid-phase extraction (SPE) of aromatic amines, which are classified as priority pollutants by US Environmental Protection Agency. Hexamethylenetetramine used for silica surface modification for the first time was employed as SPE sorbent under normal phase conditions. Hexaminium-functionalized silica demonstrated excellent extraction efficiencies for o-toluidine, 4-ethylaniline and quinoline (recoveries 101-107%), while for N,N-dimethylaniline and N-isopropylaniline recoveries were from low to moderate (14-46%). In addition, the suitability of 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica as SPE sorbent was tested under normal phase conditions. The recoveries achieved for the five aromatic amines ranged from 89 to 99%. The stability of the sorbent was evaluated during and after 150 extractions. Coefficients of variation between 4.5 and 10.2% proved a high stability of the synthesized sorbent. Elution was carried out using acetonitrile in the case of hexaminium-functionalized silica and water for 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica sorbent. After the extraction the analytes were separated and detected by liquid chromatography ultraviolet detection (LC-UV). The retention mechanism of the materials was primarily based on polar hydrogen bonding and π-π interactions. Comparison made with activated silica proved the quaternary ammonium-functionalized materials to offer different selectivity and better extraction efficiencies for aromatic amines. Finally, 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica sorbent was successfully tested for the extraction of wastewater and soil samples.

  17. Enhancing biodegradation of C16-alkyl quaternary ammonium compounds using an oxygen-based membrane biofilm reactor.

    Science.gov (United States)

    Lai, YenJung Sean; Ontiveros-Valencia, Aura; Ilhan, Zehra Esra; Zhou, Yun; Miranda, Evelyn; Maldonado, Juan; Krajmalnik-Brown, Rosa; Rittmann, Bruce E

    2017-10-15

    Quaternary ammonium compounds (QACs) (e.g., hexadecyltrimethyl-ammonium bromide, CTAB) are emerging contaminants with widespread use as surfactants and disinfectants. Because the initial step of QAC biodegradation is mono-oxygenation, QAC degraders require O2, but normal aeration leads to serious foaming. Here, we developed and tested an oxygen-based membrane biofilm reactor (O2-MBfR) that delivers O2 by diffusion through the walls of hollow-membranes to a biofilm accumulating on the outer surface of membranes. The O2-MBfR sustained QAC biodegradation even with high and toxic QAC input concentrations, up to 400 mg/L CTAB. Bubbleless O2 transfer completely eliminated foaming, and biofilm accumulation helped the QAC biodegraders resist toxicity. Pseudomonas, Achromobacter, Stenotrophomonas, and members of the Xanthomonadaceae family were dominant in the biofilm communities degrading CTAB, and their proportions depended on the O2-delivery capacity of the membranes. Bacteria capable of biodegrading QACs often harbor antibiotic resistance genes (ARGs) that help them avoid QAC toxicity. Gene copies of ARGs were detected in biofilms and liquid, but the levels of ARGs were 5- to 35-fold lower in the liquid than in the biofilm. In summary, the O2-MBfR achieved aerobic biodegradation of CTAB with neither foaming nor toxicity, and it also minimized the spread of ARGs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Synthesis, characterization and thermal properties of new aromatic quaternary ammonium bromides: precursors for ionic liquids and complexation studies

    Science.gov (United States)

    Busi, Sara; Lahtinen, Manu; Ropponen, Jarmo; Valkonen, Jussi; Rissanen, Kari

    2004-10-01

    Series of new aromatic R2R‧2N+Br- (R=benzyl, 4-methylbenzyl, 2-phenylethyl, 3-phenylpropyl; R‧=ethyl, methyl, isopropyl) or RR‧2NH+Br--type (R=benzyl, R‧=isopropyl) quaternary ammonium bromides were prepared by using novel synthetic route in which a formamide (N,N-diethylformamide, N,N-dimethylformamide, N,N-diisopropylformamide) is treated with aralkyl halide in presence of a weak base. The compounds were characterized by 1H-NMR and 13C-NMR spectroscopy and mass spectrometry. Structures of the crystalline compounds were determined by X-ray single crystal diffraction, and in addition the powder diffraction method was used to study the structural similarities between the single crystal and microcrystalline bulk material. Three of the compounds crystallized in monoclinic, two in orthorhombic and one in triclinic crystal system, showing ion pairs, which are interconnected by weak hydrogen bonds and weak π - π interactions between the phenyl rings. Three of the compounds appeared as viscous oil or waxes. Finally, TG/DTA and DSC methods were used to analyze thermal properties of the prepared compounds. The lowest melting points were obtained for diethyldi-(2-phenylethyl)ammonium bromide (122.2 °C) and for diethyldi-(3-phenylpropyl)-ammonium bromide (109.1 °C). In general, decomposition of the compounds started at 170-190 °C without identifiable cleavages, thus liquid ranges of 30-70 °C were observed for some of the compounds.

  19. Benzalkonium chloride (BAC) and dimethyldioctadecyl-ammonium bromide (DDAB), two common quaternary ammonium compounds, cause genotoxic effects in mammalian and plant cells at environmentally relevant concentrations.

    Science.gov (United States)

    Ferk, F; Misík, M; Hoelzl, C; Uhl, M; Fuerhacker, M; Grillitsch, B; Parzefall, W; Nersesyan, A; Micieta, K; Grummt, T; Ehrlich, V; Knasmüller, S

    2007-11-01

    Quaternary ammonium compounds (QACs) are cationic surfactants that are widely used as disinfectants. In the present study, we tested two important representatives, namely, benzalkonium chloride (BAC) and dimethyldioctadecyl-ammonium bromide (DDAB) in four genotoxicity tests, namely, in the Salmonella/microsome assay with strains TA 98, TA 100 and TA 102, in the single-cell gel electrophoresis (SCGE) assay with primary rat hepatocytes and in micronucleus (MN) assays with peripheral human lymphocytes and with root tip cells of Vicia faba. In the bacterial experiments, consistently negative results were obtained in the dose range between 0.001 and 110 microg per plate in the presence and absence of metabolic activation while significant induction of DNA migration was detected in the liver cells. With BAC, a moderate but significant effect was found with an exposure concentration of 1.0 mg/l while DDAB caused damage at lower doses (0.3 mg/l). The effects were not altered when the nuclei were treated with formamidopyridine glycosylase, indicating that they are not due to formation of oxidized purines. The MN assays with blood cells were carried out under identical conditions to the SCGE experiments and a significant increase was seen at the highest dose levels (BAC: 1.0 and 3.0 mg/l; DDAB: 1 mg/l). Both compounds also caused significant induction of MN as well as inhibition of cell division in plant cells, the lowest effective levels were 1.0 and 10 mg/l for DDAB and BAC, respectively. Our findings show that both chemicals induce moderate but significant genotoxic effects in eukaryotic cells at concentrations which are found in wastewaters and indicate that their release into the environment may cause genetic damage in exposed organisms. Furthermore, the direct contact of humans to QAC-containing detergents and pharmaceuticals that contain substantially higher concentrations than those which were required to cause effects in eukaryotic cells in the present study should

  20. Leaching of lead by ammonium salts and EDTA from Salvinia minima biomass produced during aquatic phytoremediation

    Energy Technology Data Exchange (ETDEWEB)

    Nunez-Lopez, Roberto Aurelio [Centro de Investigacion y Desarrollo Tecnologico en Electroquimica (CIDETEQ), Parque Tecnologico Queretaro, Sanfandila, Pedro Escobedo Qro., 76700 Mexico (Mexico)], E-mail: ndahi2000@yahoo.com; Meas, Yunny [Centro de Investigacion y Desarrollo Tecnologico en Electroquimica (CIDETEQ), Parque Tecnologico Queretaro, Sanfandila, Pedro Escobedo Qro., 76700 Mexico (Mexico)], E-mail: yunnymeas@cideteq.mx; Citlalli Gama, Silvia; Ortega Borges, Raul [Centro de Investigacion y Desarrollo Tecnologico en Electroquimica (CIDETEQ), Parque Tecnologico Queretaro, Sanfandila, Pedro Escobedo Qro., 76700 Mexico (Mexico); Olguin, Eugenia J. [Instituto de Ecologia (INECOL), Apdo. Postal 63, Xalapa, Veracruz 91000 (Mexico)

    2008-06-15

    Plant biomass harvested after heavy-metal phytoremediation must be considered as a hazardous waste that should be contained or treated appropriately before disposal or reuse. As a potential method to detoxify the biomass and to convert this material to a suitable fertilizer or mulch, leaching of lead (Pb) from Salvinia minima biomass was studied by testing water, several aqueous ammonium salts, and EDTA solution as lead extractants. The research was carried out in two phases: (i) a leaching study to determine the lead-extraction efficiency of the different leachants, and (ii) a thermodynamic analysis to identify the likely reactions and stable Pb(II) species formed in the leaching systems of the most efficient leachants. Experimentally, lead concentrations measured in leached biomass and in leachates were significantly different among the various leachants. It was determined that the extraction strength of the leachants followed the order: EDTA > ammonium oxalate > water {approx} ammonium nitrate > ammonium acetate, achieving Pb extraction efficiencies of 99%, 70%, 7.2%, 6.9% and 1.3%, respectively, in single-stage extractions. The thermodynamic study indicated that the dominant species produced by the leaching process should be the soluble species PbEDTA{sup 2-} for EDTA system, and the insoluble Pb(COO){sub 2S} precipitate for the oxalate system.

  1. Physical and chemical properties of an antimicrobial Bis-GMA free dental resin with quaternary ammonium dimethacrylate monomer.

    Science.gov (United States)

    Huang, Qi-ting; He, Jing-wei; Lin, Zheng-mei; Liu, Fang; Lassila, Lippo V J; Vallittu, Pekka K

    2016-03-01

    The objective of this study was to evaluate the antibacterial activity, physicochemical properties of the quaternary ammonium dimethacrylate monomer N,N-bis[2-(3-(methacryloyloxy)propanamido)-ethyl]-N-methylhexadecyl ammonium bromide (IMQ-16) containing diurethane dimethacrylate (UDMA)/tricyclodecane dimethanol diacrylate (SR833s) resin system and compare with bisphenylglycidyl dimethacrylate (Bis-GMA)/triethylene glycol dimethacrylate (TEGDMA) resin system. It was hypothesized that the physical and chemical properties of the experimental polymers would be comparable with Bis-GMA/TEGDMA polymer and IMQ-16 monomer could endow the UDMA/SR833s resin with antibacterial activity. Double bond conversion (DC) was measured using Fourier transform infrared spectroscopy (FTIR). Mechanical properties including flexural strength (FS) and flexural modulus (FM) were measured by three-point bending test with bars of 2mm×2mm×25mm. Water sorption (WS) and solubility (WSL) were also investigated. Antibacterial activity of obtained polymers against Streptococcus mutans Ingbitt (S. mutans) was tested through direct contact test (DCT). The presence of antibacterial activity due to soluble components was also investigated by agar diffusion test (ADT). All of the polymers containing IMQ-16 exhibited improvements in WS and WSL, while maintaining equivalent DC and FS relative to the Bis-GMA/TEGDMA control system. Incorporation of 17% and 20% of IMQ-16 into UDMA/SR833s resin reduced the viable counts of S. mutans after incubation on the surface of the materials and produced no inhibition zones around the cured discs in ADT. UDMA/SR833s resin system is promising to formulate an antibacterial polymer with equivalent or even higher physicochemical properties relative to Bis-GMA/TEGDMA formulation. IMQ-16 is capable to endow UDMA/SR833s resin system with significant antibacterial activity when the mass ratio is 17% or 20%.

  2. MODIFICATION OF EPOXY RESIN WITH POLYSILOXANE BEARING PENDANT QUATERNARY AMMONIUM GROUPS

    Institute of Scientific and Technical Information of China (English)

    Zuo-xin Huang; Ying Huang; Yun-zhao Yu

    2002-01-01

    Polysiloxane bearing pendant quatemary ammonium groups (PSI) was used to modify the surface properties ofepoxy resins. In the cured resin, PSI formed the dispersed phase. Remarkable enrichment and gradient distribution ofpolysiloxane on the surface region of the epoxy resins were demonstrated by XPS analysis. The composition and propertiesof the surface of PSI-modified epoxy resin, which is in contact with the mold, are dependent on the material of the mold.Through the incorporation of PSI, epoxy resins with low surface energy and low friction coefficient were obtained.Polysiloxane with lower ionic group content shows a higher degree of enrichment on the resin surface and leads to a highercontact angle against water, while the polysiloxane having optimum compatibility with the epoxy resin shows a greater effectin reducing the static friction coefficient of the resin against glass.

  3. The toxicity of the quaternary ammonium compound benzalkonium chloride alone and in mixtures with other anionic compounds to bacteria in test systems with Vibrio fischeri and Pseudomonas putida.

    Science.gov (United States)

    Sütterlin, H; Alexy, R; Kümmerer, K

    2008-10-01

    Mixtures of chemicals are present in the aquatic environment but standard testing methods assess only single compounds. One aspect of this question is the importance of the formation of ionic pairs, for example from quaternary ammonium compounds with organic anions, and the significance of the ionic pairs for bacterial toxicity in the aquatic environment. The aim of the present study was to investigate the toxicity of the cationic quaternary ammonium compound benzalkonium chloride (BAC) against aquatic bacteria in the presence of substances commonly found in wastewater, such as the anionic surfactant linear alkylbenzene sulfonate (LAS), naphthalene sulfonic acid (NSA), sodium dodecylsulfonate (SDS), and benzene sulfonic acid (BSA). The growth inhibition test with Pseudomonas putida and the Vibrio fischeri luminescent inhibition test were used to determine the toxicity of single compounds and compound mixtures. The results found in this study indicate that ion pair formation is of minor significance under the test conditions applied here.

  4. Integrating conjugative elements as vectors of antibiotic, mercury, and quaternary ammonium compound resistance in marine aquaculture environments.

    Science.gov (United States)

    Rodríguez-Blanco, Arturo; Lemos, Manuel L; Osorio, Carlos R

    2012-05-01

    The presence of SXT/R391-related integrating conjugative elements (ICEs) in bacterial strains isolated from fish obtained from marine aquaculture environments in 2001 to 2010 in the northwestern Iberian Peninsula was studied. ICEs were detected in 12 strains taxonomically related to Vibrio scophthalmi (3 strains), Vibrio splendidus (5 strains), Vibrio alginolyticus (1 strain), Shewanella haliotis (1 strain), and Enterovibrio nigricans (2 strains), broadening the known host range able to harbor SXT/R391-like ICEs. Variable DNA regions, which confer element-specific properties to ICEs of this family, were characterized. One of the ICEs encoded antibiotic resistance functions in variable region III, consisting of a tetracycline resistance locus. Interestingly, hot spot 4 included genes providing resistance to rifampin (ICEVspPor2 and ICEValPor1) and quaternary ammonium compounds (QACs) (ICEEniSpa1), and variable region IV included a mercury resistance operon (ICEVspSpa1 and ICEEniSpa1). The S exclusion group was more represented than the R exclusion group, accounting for two-thirds of the total ICEs. Mating experiments allowed ICE mobilization to Escherichia coli strains, showing the corresponding transconjugants' rifampin, mercury, and QAC resistance. These results show the first evidence of ICEs providing rifampin and QAC resistances, suggesting that these mobile genetic elements contribute to the dissemination of antimicrobial, heavy metal, and QAC resistance determinants in aquaculture environments.

  5. UV-Vis spectrophotometric studies of self-oxidation/dissociation of quaternary ammonium permanganates (QAP) - impact of solvent polarity

    Science.gov (United States)

    Bank, Suraj Prakash; Guru, Partha Sarathi; Dash, Sukalyan

    2015-05-01

    Self-oxidation/dissociation of some quaternary ammonium permanganates (QAPs), such as cetyltrimethylammonium permanganate (CTAP) and tetrabutylammonium permanganate (TBAP), have been studied spectrophotometrically in six different organic solvent media of different polarities wherein the compounds show good solubility and stability. The optical densities of the substrates at zero time (ODo) and first-order rate constants of dissociation (k1) have been determined from their successive scanning for 40 min. At comparable experimental conditions, absorption capabilities of the substrates are compared from the ODo values in various organic media; the stability of the solutions is compared from the successive scan spectra in those media. The ODo values and the k1 values have been plotted against some solvent parameters to understand their effects on the absorbance and reactivity of the QAPs. These data are also subjected to multiple regression analysis to explain the influence of various solvent parameters on the ion-pairing properties of the substrates, thus elucidating their effects on the process of self-oxidation/dissociation of the substrates.

  6. Performance properties and antibacterial activity of crosslinked films of quaternary ammonium modified starch and poly(vinyl alcohol).

    Science.gov (United States)

    Sekhavat Pour, Zahra; Makvandi, Pooyan; Ghaemy, Mousa

    2015-09-01

    There has been a growing interest in developing antibacterial polymeric materials. In the present work, novel antibacterial cross-linked blend films were prepared based on polyvinyl alcohol (PVA) and quaternary ammonium starch (ST-GTMAC) using citric acid (CA) as plasticizer and glutaraldehyde (GA) as cross-linker. The ST-GTMAC was successfully synthesized from reaction between water-soluble oxidized starch and glycidyltrimethylammonium chloride (GTMAC). The effect of ST-GTMAC, CA and GA contents on the swelling, solubility, mechanical and thermal properties of the films was investigated. It was found that incorporation of ST-GTMAC reduced UV-transmittance and provided antibacterial properties, increasing GA content increased tensile strength and decreased solubility and swelling degree of the films, while CA acted as plasticizer when its concentration was above 10 wt%. The results showed that ST-GTMAC/PVA/CA/GA film has fair antibacterial activity against Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. These results suggest that the prepared film might be used as potential antibacterial material in medical and packaging applications.

  7. Characterisation and discrimination of various types of lac resin using gas chromatography mass spectrometry techniques with quaternary ammonium reagents.

    Science.gov (United States)

    Sutherland, K; del Río, J C

    2014-04-18

    A variety of lac resin samples obtained from artists' suppliers, industrial manufacturers, and museum collections were analysed using gas chromatography mass spectrometry (GCMS) and reactive pyrolysis GCMS with quaternary ammonium reagents. These techniques allowed a detailed chemical characterisation of microgram-sized samples, based on the detection and identification of derivatives of the hydroxy aliphatic and cyclic (sesquiterpene) acids that compose the resin. Differences in composition could be related to the nature of the resin, e.g. wax-containing (unrefined), bleached, or aged samples. Furthermore, differences in the relative abundances of aliphatic hydroxyacids appear to be associated with the biological source of the resin. The diagnostic value of newly characterised lac components, including 8-hydroxyacids, is discussed here for the first time. Identification of derivatised components was aided by AMDIS deconvolution software, and discrimination of samples was enhanced by statistical evaluation of data using principal component analysis. The robustness of the analyses, together with the minimal sample size required, make these very powerful approaches for the characterisation of lac resin in museum objects. The value of such analyses for enhancing the understanding of museum collections is illustrated by two case studies of objects in the collection of the Philadelphia Museum of Art: a restorer's varnish on a painting by Luca Signorelli, and a pictorial inlay in an early nineteenth-century High Chest by George Dyer. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Equilibrium adsorption of caffeic, chlorogenic and rosmarinic acids on cationic cross-linked starch with quaternary ammonium groups.

    Science.gov (United States)

    Simanaviciute, Deimante; Klimaviciute, Rima; Rutkaite, Ramune

    2017-02-01

    In the present study, the equilibrium adsorption of caffeic acid (CA) and its derivatives, namely, chlorogenic (CGA) and rosmarinic (RA) acids on cationic cross-linked starch (CCS) with degree of substitution of quaternary ammonium groups of 0.42 have been investigated in relation to the structure and acidity of phenolic acids. The Langmuir, Freundlich and Dubinin-Radushkevich adsorption models have been used to describe the equilibrium adsorption of CA, CGA and RA from their initial solutions and solutions having the equimolar amount of NaOH at different temperatures. In the case of adsorption from the initial solutions of acids the values of adsorption parameters were closely related to the dissociation constants of investigated acids. According to the increasing effectiveness of adsorption, phenolic acids could be arranged in the following order: CA

  9. Leveling effects of ammonium salts on thermal stabilities of polyethylene glycols.

    Science.gov (United States)

    Xia, Juan; Song, Le Xin; Liu, Wei; Teng, Yue

    2013-10-28

    In this work, the thermal stabilities of a series of polyethylene glycols (PEG 4000, 6000 and 10000) were investigated after compositing with different kinds of inorganic salts, such as ammonium molybdate tetrahydrate (AMT), NH4VO3, (NH4)2SO4, NH4NO3, Na2SO4, Na2MoO4. It was first observed that all the ammonium salts exerted leveling effects for the thermal stabilities of the PEGs. In other words, the presence of the ammonium salts caused the occurrence of the maximum decomposition rates of the PEGs with the same repeat sequence but different chain lengths at almost the same temperatures. Leveling effects were defined by three parameters: leveling spans, leveling degrees and dispersion degrees of leveling. Further experiments revealed that leveling effects also occur in similar types of polymers: polypropylene glycols (PPG 2000, 3000 and 4000). A series of independent experiments including Fourier transformation infrared spectroscopy, Raman spectroscopy, differential scanning calorimetry, time-of-flight mass spectrometry, conductivity and field-emission scanning electron microscopy were performed to explore the origin of leveling effects. We consider that the interaction between inorganic ions and polymer molecules and the Hofmeister effect of ions in solution are two important factors affecting the stability of salt–polymer composites, because they can contribute to decrease the interaction between the polymer chains, leading to changes in the conformation and pyrolysis mode of polymers. We believe that the finding of leveling effects would be significant for both basic and applied research of soft matter.

  10. Research Progress on Analytical Methods of Quaternary Ammonium Compounds%季铵盐类消毒剂及其检测方法的研究进展

    Institute of Scientific and Technical Information of China (English)

    杨艳伟; 朱英

    2011-01-01

    季铵盐类消毒剂是一类重要的化学消毒剂,广泛应用于各个领域,其有关研究和进展一直受到广泛关注.该研究介绍了季铵盐类消毒剂的结构特点、杀菌机制及其影响因素,重点介绍并分析了其主要分析方法(包括滴定法、紫外-可见分光光度法、离子色谱法、液相色谱法和气相色谱质谱法)的测定原理、应用范围及优缺点.%Quaternary ammonium disinfectant is one of important chemical disinfectants and widely used in various fields. Its reaserch as well as development had attracted wide acttentions. In this article the structural features, sterilizing mechanism and influencing factors of quaternary ammonium disinfectant were presented. Several analytical methods of quaternary ammonium compounds including diphasic titration, ultra violet -visible spectrophotometry, ion chromatography,liquid chromatography and gas chromatography-mass spectrometry were introduced in detail. Moreover, the principle, application range, advantage and disadvantage of different methods were discussed.

  11. New Diethyl Ammonium Salt of Thiobarbituric Acid Derivative: Synthesis, Molecular Structure Investigations and Docking Studies

    OpenAIRE

    Assem Barakat; Abdullah Mohammed Al-Majid; Saied M. Soliman; Gehad Lotfy; Ghabbour, Hazem A; Hoong-Kun Fun; Abdul Wadood; Ismail Warad; Joseph C. Sloop

    2015-01-01

    The synthesis of the new diethyl ammonium salt of diethylammonium(E)-5-(1,5-bis(4-fluorophenyl)-3-oxopent-4-en-1-yl)-1,3-diethyl-4,6-dioxo-2-thioxohexaydropyrimidin-5-ide 3 via a regioselective Michael addition of N,N-diethylthiobarbituric acid 1 to dienone 2 is described. In 3, the carboanion of the thiobarbituric moiety is stabilized by the strong intramolecular electron delocalization with the adjacent carbonyl groups and so the reaction proceeds without any cyclization. The molecular stru...

  12. The Influence of Interfering Substances on the Antimicrobial Activity of Selected Quaternary Ammonium Compounds

    Directory of Open Access Journals (Sweden)

    Paula A. Araújo

    2013-01-01

    Full Text Available Standard cleaning processes may not remove all the soiling typically found in food industry, such as carbohydrates, fats, or proteins. Contaminants have a high impact in disinfection as their presence may reduce the activity of disinfectants. The influence of alginic acid, bovine serum albumin, yeast extract, and humic acids was assessed on the antimicrobial activities of benzalkonium chloride and cetyltrimethyl ammonium bromide against Bacillus cereus vegetative cells and Pseudomonas fluorescens. The bacteria (single and consortium were exposed to surfactants (single and combined in the absence and presence of potential disinfection interfering substances. The antimicrobial effects of the surfactants were assessed based on the bacterial respiratory activity measured by oxygen uptake rate due to glucose oxidation. The tested surfactants were efficient against both bacteria (single and consortium with minimum bactericidal concentrations ranging from 3 to 35 mg·L−1. The strongest effect was caused by humic acids that severely quenched antimicrobial action, increasing the minimum bactericidal concentration of the surfactants on P. fluorescens and the consortium. The inclusion of the other interfering substances resulted in mild interferences in the antibacterial activity. This study clearly demonstrates that humic acids should be considered as an antimicrobial interfering substance in the development of disinfection strategies.

  13. The Influence of Interfering Substances on the Antimicrobial Activity of Selected Quaternary Ammonium Compounds.

    Science.gov (United States)

    Araújo, Paula A; Lemos, Madalena; Mergulhão, Filipe; Melo, Luís; Simões, Manuel

    2013-01-01

    Standard cleaning processes may not remove all the soiling typically found in food industry, such as carbohydrates, fats, or proteins. Contaminants have a high impact in disinfection as their presence may reduce the activity of disinfectants. The influence of alginic acid, bovine serum albumin, yeast extract, and humic acids was assessed on the antimicrobial activities of benzalkonium chloride and cetyltrimethyl ammonium bromide against Bacillus cereus vegetative cells and Pseudomonas fluorescens. The bacteria (single and consortium) were exposed to surfactants (single and combined) in the absence and presence of potential disinfection interfering substances. The antimicrobial effects of the surfactants were assessed based on the bacterial respiratory activity measured by oxygen uptake rate due to glucose oxidation. The tested surfactants were efficient against both bacteria (single and consortium) with minimum bactericidal concentrations ranging from 3 to 35 mg·L(-1). The strongest effect was caused by humic acids that severely quenched antimicrobial action, increasing the minimum bactericidal concentration of the surfactants on P. fluorescens and the consortium. The inclusion of the other interfering substances resulted in mild interferences in the antibacterial activity. This study clearly demonstrates that humic acids should be considered as an antimicrobial interfering substance in the development of disinfection strategies.

  14. Salt diapirs in the Dead Sea basin and their relationship to Quaternary extensional tectonics

    Science.gov (United States)

    Al-Zoubi, A.; ten Brink, U.S.

    2001-01-01

    Regional extension of a brittle overburden and underlying salt causes differential loading that is thought to initiate the rise of reactive diapirs below and through regions of thin overburden. We present a modern example of a large salt diapir in the Dead Sea pull-apart basin, the Lisan diapir, which we believe was formed during the Quaternary due to basin transtension and subsidence. Using newly released seismic data that are correlated to several deep wells, we determine the size of the diapir to be 13 x 10 km. its maximum depth 7.2 km. and its roof 125 m below the surface. From seismic stratigraphy, we infer that the diapir started rising during the early to middle Pleistocene as this section of the basin underwater rapid subsidence and significant extension of the overburden. During the middle to late Pleistocene, the diapir pierced through the extensionally thinned overburden, as indicated by rim synclines, which attest to rapid salt withdrawal from the surrounding regions. Slight positive topography above the diapir and shallow folded horizons indicate that it is still rising intermittently. The smaller Sedom diapir, exposed along the western bounding fault of the basin is presently rising and forms a 200 m-high ridge. Its initiation is explained by localized E-W extension due monoclinal draping over the edge of a rapidly subsiding basin during the early to middle Pleistocene, and its continued rise by lateral squeezing due to continued rotation of the Amazyahu diagonal fault. ?? 2001 Elsevier Science Ltd. All rights reserved.

  15. separation of strontium and cesium from ternary and quaternary lithium chloride-potassium chloride salts via melt crystallization

    Directory of Open Access Journals (Sweden)

    Ammon N. Williams

    2015-12-01

    Full Text Available Separation of cesium chloride (CsCl and strontium chloride (SrCl2 from the lithium chloride-potassium chloride (LiCl-KCl salt was studied using a melt crystallization process similar to the reverse vertical Bridgeman growth technique. A ternary SrCl2-LiCl-KCl salt was explored at similar growth rates (1.8–5 mm/h and compared with CsCl ternary results to identify similarities. Quaternary experiments were also conducted and compared with the ternary cases to identify trends and possible limitations to the separations process. In the ternary case, as much as 68% of the total salt could be recycled per batch process. In the quaternary experiments, separation of Cs and Sr was nearly identical at the slower rates; however, as the growth rate increased, SrCl2 separated more easily than CsCl. The quaternary results show less separation and rate dependence than in both ternary cases. As an estimated result, only 51% of the total salt could be recycled per batch. Furthermore, two models have been explored to further understand the growth process and separation. A comparison of the experimental and modeling results reveals that the nonmixed model fits reasonably well with the ternary and quaternary data sets. A dimensional analysis was performed and a correlation was identified to semipredict the segregation coefficient.

  16. Enhanced water-solubility and antibacterial activity of novel chitosan derivatives modified with quaternary phosphonium salt.

    Science.gov (United States)

    Zhu, Dan; Cheng, Honghao; Li, Jianna; Zhang, Wenwen; Shen, Yuanyuan; Chen, Shaojun; Ge, Zaochuan; Chen, Shiguo

    2016-04-01

    Chitosan (CS) has been widely recognized as an important biomaterial due to its good antimicrobial activity, biocompatibility and biodegradability. However, CS is insoluble in water in neutral and alkaline aqueous solution due to the linear aggregation of chain molecules and the formation of crystallinity. This is one of the key factors that limit its practical applications. Therefore, improving the solubility of CS in neutral and alkaline aqueous solution is a primary research direction for biomedical applications. In this paper, a reactive antibacterial compound (4-(2,5-Dioxo-pyrrolidin-1-yloxycarbonyl)-benzyl)-triphenyl-phosphonium bromide (NHS-QPS) was synthesized for chemical modification of CS, and a series of novel polymeric antimicrobial agents, N-quaternary phosphonium chitosan derivatives (N-QPCSxy, x=1-2,y=1-4) were obtained. The water solubilities and antibacterial activities of N-QPCSxy against Escherichia coli and Staphylococcus aureus were evaluated compare to CS. The water solubility of N-QPCSxy was all better than that of CS at neutral pH aqueous solution, particularly, N-QPCS14 can be soluble in water over the pH range of 3 to 12. The antibacterial activities of CS derivatives were improved by introducing quaternary phosphonium salt, and antibacterial activity of N-QPCSxy increases with degree of substitution. Overall, N-QPCS14 represents a novel antibacterial polymer material with good antibacterial activity, waters solubility and low cytotoxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Potential Impact of the Resistance to Quaternary Ammonium Disinfectants on the Persistence of Listeria monocytogenes in Food Processing Environments

    Science.gov (United States)

    Martínez-Suárez, Joaquín V.; Ortiz, Sagrario; López-Alonso, Victoria

    2016-01-01

    The persistence of certain strains of Listeria monocytogenes, even after the food processing environment has been cleaned and disinfected, suggests that this may be related to phenomena that reduce the concentration of the disinfectants to subinhibitory levels. This includes (i) the existence of environmental niches or reservoirs that are difficult for disinfectants to reach, (ii) microorganisms that form biofilms and create microenvironments in which adequate concentrations of disinfectants cannot be attained, and (iii) the acquisition of resistance mechanisms in L. monocytogenes, including those that lead to a reduction in the intracellular concentration of the disinfectants. The only available data with regard to the resistance of L. monocytogenes to disinfectants applied in food production environments refer to genotypic resistance to quaternary ammonium compounds (QACs). Although there are several well-characterized efflux pumps that confer resistance to QACs, it is a low-level resistance that does not generate resistance to QACs at the concentrations applied in the food industry. However, dilution in the environment and biodegradation result in QAC concentration gradients. As a result, the microorganisms are frequently exposed to subinhibitory concentrations of QACs. Therefore, the low-level resistance to QACs in L. monocytogenes may contribute to its environmental adaptation and persistence. In fact, in certain cases, the relationship between low-level resistance and the environmental persistence of L. monocytogenes in different food production chains has been previously established. The resistant strains would have survival advantages in these environments over sensitive strains, such as the ability to form biofilms in the presence of increased biocide concentrations. PMID:27199964

  18. One-year water-ageing of calcium phosphate composite containing nano-silver and quaternary ammonium to inhibit biofilms

    Institute of Scientific and Technical Information of China (English)

    Lei Cheng; Ke Zhang; Chen-Chen Zhou; Michael D Weir; Xue-Dong Zhou; Hockin HK Xu

    2016-01-01

    Dental composites are commonly used restorative materials; however, secondary caries due to biofilm acids remains a major problem. The objectives of this study were (1) to develop a composite containing quaternary ammonium dimethacrylate (QADM), nanoparticles of silver (NAg), and nanoparticles of amorphous calcium phosphate (NACP), and (2) to conduct the first investigation of the mechanical properties, biofilm response and acid production vs water-ageing time from 1 day to 12 months. A 4 × 5 design was utilized, with four composites (NACP-QADM composite, NACP-NAg composite, NACP-QADM-NAg composite, and a commercial control composite), and five water-ageing time periods (1 day, and 3, 6, 9, and 12 months). After each water-ageing period, the mechanical properties of the resins were measured in a three-point flexure, and antibacterial properties were tested via a dental plaque biofilm model using human saliva as an inoculum. After 12 months of water-ageing, NACP-QADM-NAg had a flexural strength and elastic modulus matching those of the commercial control (P40.1). Incorporation of QADM or NAg into the NACP composite greatly reduced biofilm viability, metabolic activity and acid production. A composite containing both QADM and NAg possessed a stronger antibacterial capability than one with QADM or NAg alone (Po0.05). The anti-biofilm activity was maintained after 12 months of water-ageing and showed no significant decrease with increasing time (P40.1). In conclusion, the NACP-QADM-NAg composite decreased biofilm viability and lactic acid production, while matching the load-bearing capability of a commercial composite. There was no decrease in its antibacterial properties after 1 year of water-ageing. The durable antibacterial and mechanical properties indicate that NACP-QADM-NAg composites may be useful in dental restorations to combat caries.

  19. One-year water-ageing of calcium phosphate composite containing nano-silver and quaternary ammonium to inhibit biofilms.

    Science.gov (United States)

    Cheng, Lei; Zhang, Ke; Zhou, Chen-Chen; Weir, Michael D; Zhou, Xue-Dong; Xu, Hockin H K

    2016-09-29

    Dental composites are commonly used restorative materials; however, secondary caries due to biofilm acids remains a major problem. The objectives of this study were (1) to develop a composite containing quaternary ammonium dimethacrylate (QADM), nanoparticles of silver (NAg), and nanoparticles of amorphous calcium phosphate (NACP), and (2) to conduct the first investigation of the mechanical properties, biofilm response and acid production vs water-ageing time from 1 day to 12 months. A 4 × 5 design was utilized, with four composites (NACP-QADM composite, NACP-NAg composite, NACP-QADM-NAg composite, and a commercial control composite), and five water-ageing time periods (1 day, and 3, 6, 9, and 12 months). After each water-ageing period, the mechanical properties of the resins were measured in a three-point flexure, and antibacterial properties were tested via a dental plaque biofilm model using human saliva as an inoculum. After 12 months of water-ageing, NACP-QADM-NAg had a flexural strength and elastic modulus matching those of the commercial control (P>0.1). Incorporation of QADM or NAg into the NACP composite greatly reduced biofilm viability, metabolic activity and acid production. A composite containing both QADM and NAg possessed a stronger antibacterial capability than one with QADM or NAg alone (P0.1). In conclusion, the NACP-QADM-NAg composite decreased biofilm viability and lactic acid production, while matching the load-bearing capability of a commercial composite. There was no decrease in its antibacterial properties after 1 year of water-ageing. The durable antibacterial and mechanical properties indicate that NACP-QADM-NAg composites may be useful in dental restorations to combat caries.

  20. Effects of quaternary ammonium chain length on the antibacterial and remineralizing effects of a calcium phosphate nanocomposite

    Institute of Scientific and Technical Information of China (English)

    Ke Zhang; Lei Cheng; Michael D Weir; Yu-Xing Bai; Hockin HK Xu

    2016-01-01

    Composites containing nanoparticles of amorphous calcium phosphate (NACP) remineralize tooth lesions and inhibit caries. A recent study synthesized quaternary ammonium methacrylates (QAMs) with chain lengths (CLs) of 3–18 and determined their effects on a bonding agent. This study aimed to incorporate these QAMs into NACP nanocomposites for the first time to simultaneously endow the material with antibacterial and remineralizing capabilities and to investigate the effects of the CL on the mechanical and biofilm properties. Five QAMs were synthesized: DMAPM (CL3), DMAHM (CL6), DMADDM (CL12), DMAHDM (CL16), and DMAODM (CL18). Each QAM was incorporated into a composite containing 20% NACP and 50% glass fillers. A dental plaque microcosm biofilm model was used to evaluate the antibacterial activity. The flexural strength and elastic modulus of nanocomposites with QAMs matched those of a commercial control composite (n 5 6; P . 0.1). Increasing the CL from 3 to 16 greatly enhanced the antibacterial activity of the NACP nanocomposite (P , 0.05); further increasing the CL to 18 decreased the antibacterial potency. The NACP nanocomposite with a CL of 16 exhibited biofilm metabolic activity and acid production that were 10-fold lesser than those of the control composite. The NACP nanocomposite with a CL of 16 produced 2-log decreases in the colony-forming units (CFU) of total microorganisms, total streptococci, and mutans streptococci. In conclusion, QAMs with CLs of 3–18 were synthesized and incorporated into an NACP nanocomposite for the first time to simultaneously endow the material with antibacterial and remineralization capabilities. Increasing the CL reduced the metabolic activity and acid production of biofilms and caused a 2-log decrease in CFU without compromising the mechanical properties. Nanocomposites exhibiting strong anti-biofilm activity, remineralization effects, and mechanical properties are promising materials for tooth restorations that inhibit

  1. Versatile methods for synthesizing organic acid salts of quaternary berberine-type alkaloids as anti-ulcerative colitis agents.

    Science.gov (United States)

    Zhang, Zhi-Hui; Li, Jing; Zhang, Hai-Jing; Deng, An-Jun; Wu, Lian-Qiu; Li, Zhi-Hong; Song, Hong-Rui; Wang, Wen-Jie; Qin, Hai-Lin

    2016-06-01

    Two versatile methods to synthesize kinds of organic acid salts of quaternary berberine-type alkaloids were investigated in order to determine which is more efficient to improve the liposolubility of the target compounds and to explore the efficacy of the target compounds as anti-ulcerative colitis (UC) agents. Overall evaluation according to the reaction results and yields of the final products indicated that the synthetic method using tertiary (±)-8-acylmethyldihydroberberine-type alkaloids as key intermediates is superior to that of using tertiary dihydroberberine-type alkaloids as intermediates. Ten target compounds were synthesized using quaternary berberine chloride and quaternary coptisine chloride as starting materials, respectively, and the anti-UC activity of some target compounds was evaluated in an in vitro x-box-binding protein 1 (XBP1) transcriptional activity assay using dual luciferase reporter detection. At 10 μM, the tested compounds were found to activate the transcription of XBP1 target at almost the same level as that of quaternary coptisine chloride. The synthesized target compounds were also found to share higher liposolubility than the inorganic acid salts of quaternary berberine-type alkaloid.

  2. Low-temperature rapid syntheses of high-quality ZnO nanostructure arrays induced by ammonium salt

    Science.gov (United States)

    Zhao, Ying; Tang, Yang; Han, Zhihua

    2017-01-01

    We have developed a simple ammonium ion-assisted hydrothermal method for the fast preparation of high quality Zinc Oxide (ZnO) nanorod arrays. Ammonium salts were introduced into typically hydrothermal growth solutions formed from Zinc acetate (ZnAc2) and hexamethylenetetramine (HMTA). Scanning electron microscope (SEM), X-ray diffractometer (XRD), High resolution transmission electron microscopic (HRTEM) and photoluminescence (PL) measurements revealed that the growth rate of ZnO nanorods was promoted by adding ammonium salts and the as-grown ZnO nanostructure arrays showed remarkably low defect density. Upon addition of ammonium salt to the hydrothermal reaction solution, complex Zn(NH3)42+ was formed by Zn2+ capturing NH3 molecules dissociated from HMTA. The improvement of growth rate and optical property of the ZnO nanostructure arrays was attributed to positively charged Zn(NH3)42+ attracting oxygen rich OH- in the growth sites of ZnO for hydrolysis reaction and simultaneously inhibiting the defect. Our results demonstrated that ammonium salt can act as a new paradigm to control morphology and quality of the ZnO microstructures.

  3. Modes in the size distributions and neutralization extent of fog-processed ammonium salt aerosols observed at Canadian rural locations

    Directory of Open Access Journals (Sweden)

    X. H. Yao

    2012-02-01

    Full Text Available Among the 192 samples of size-segregated water-soluble inorganic ions collected using a Micro-Orifice Uniform Deposit Impactor (MOUDI at eight rural locations in Canada, ten samples were identified to have gone through fog processing. The supermicron particle modes of ammonium salt aerosols were found to be the fingerprint of fog processed aerosols. However, the patterns and the sizes of the supermicron modes varied with ambient temperature (T and particle acidity and also differed between inland and coastal locations. Under T > 0 °C condition, fog-processed ammonium salt aerosols were completely neutralized and had a dominant mode at 1–2 μm and a minor mode at 5–10 μm if particles were in neutral condition, and ammonium sulfate was incompletely neutralized and only had a 1–2 μm mode if particles were in acidic conditions. Under T < 0 °C at the coastal site, fog-processed aerosols exhibited a bi-modal size distribution with a dominant mode of incompletely-neutralized ammonium sulfate at about 3 μm and a minor mode of completely-neutralized ammonium sulfate at 8–9 μm. Under T < 0 °C condition at the inland sites, fog-processed ammonium salt aerosols were sometimes completely neutralized and sometimes incompletely neutralized, and the size of the supermicron mode was in the range from 1 to 5 μm. Overall, fog-processed ammonium salt aerosols under T < 0 °C condition were generally distributed at larger size (e.g., 2–5 μm than those under T > 0 °C condition (e.g., 1–2 μm.

  4. Synthesis and Antitumor Activity of Novel Castor Oil-based Quaternary Ammonium%新型蓖麻油基季铵盐的合成及其抑菌性能

    Institute of Scientific and Technical Information of China (English)

    谢友利; 张猛; 周永红; 杨晓慧

    2012-01-01

    Two kinds of novel castor oil-based quaternary ammonium were synthesized from the starting material of methyl ricinoleate by amidation reaction and quaternization reaction. Their structures were characterized by means of FTIR,1HNMR, 13CNMR and ESI( MS). The bactericidal activity of the novel castor oil-based quaternary ammonium salts was evaluated by inhibitory zone diameters against E. coli and S. aureus. It is found that they have antibacterial activity. The antibacterial activity of N, N-dimethyl-N-ethyl-castor oil acid amide propyl bromide is stronger than that of N-benzyl-N,N-dimethyl-castor oil acid amide propyl bromide.%以蓖麻油酸甲酯为起始原料,与N,N-二甲基-1,3-丙二胺和溴化苄、溴乙烷通过酰胺化反应和季铵化反应生成了新型蓖麻油基季铵盐,其结构经FTIR、1HNMR、13CNMR及ESI-MS进行了确证.采用抑菌圈直径法对目标产物的抑菌性能进行了测试,结果表明,两种季铵盐均有一定的抑菌活性,N,N-二甲基-N-乙基-蓖麻油酸酰胺丙基溴化铵的抑菌活性略强于N,N-二甲基-N-苄基-蓖麻油酸酰胺丙基溴化铵.

  5. Oxidative Leaching of metals from electronic waste with solutions based on quaternary ammonium salts

    OpenAIRE

    Pinheiro, Diana

    2009-01-01

    The treatment of electric and electronic waste (WEEE) is a problem which receives ever more attention. An inadequate treatment results in harmful products ending up in the environment. This project intends to investigate the possibilities of an alternative route for recycling of metals from printed circuit boards (PCBs) obtained from rejected computers. The process is based on aqueous solutions composed of an etchant, either 0.2 M CuCl2.2H2O or 0.2 M FeCl3.6H2O, and a quater...

  6. Quantitative analysis of ammonium salts in coking industrial liquid waste treatment process based on Raman spectroscopy

    Science.gov (United States)

    Cao, Ya-Nan; Wang, Gui-Shi; Tan, Tu; Cai, Ting-Dong; Liu, Kun; Wang, Lei; Zhu, Gong-Dong; Mei, Jiao-Xu

    2016-10-01

    Quantitative analysis of ammonium salts in the process of coking industrial liquid waste treatment is successfully performed based on a compact Raman spectrometer combined with partial least square (PLS) method. Two main components (NH4SCN and (NH4)2S2O3) of the industrial mixture are investigated. During the data preprocessing, wavelet denoising and an internal standard normalization method are employed to improve the predicting ability of PLS models. Moreover, the PLS models with different characteristic bands for each component are studied to choose a best resolution. The internal and external calibration results of the validated model show a mass percentage error below 1% for both components. Finally, the repeatabilities and reproducibilities of Raman and reference titration measurements are also discussed. Project supported by the National Natural Science Foundation of China (Grant Nos. 41405022 and 61475068).

  7. Fluorescence and physical properties of the organic salt 2-chloro-4-nitrobenzoate–3-ammonium-phenol

    Energy Technology Data Exchange (ETDEWEB)

    Mani, Rajaboopathi, E-mail: mrajaboopathi@gmail.com [Department of Physics, Periyar University, Salem 636 011, Tamilnadu (India); Rietveld, Ivo B.; Nicolaï, Béatrice [Laboratoire de Chimie Physique, Faculté de Pharmacie, Université Paris Descartes, 75006 Paris (France); Varadharajan, Krishnakumar, E-mail: vkrishna_kumar@yahoo.com [Department of Physics, Periyar University, Salem 636 011, Tamilnadu (India); Louhi-Kultanen, Marjatta [Department of Chemical Technology, Lappeenranta University of Technology, Lappeenranta 53851 (Finland); Narasimhan, Surumbarkuzhali [Department of Physics, Government Arts College (Autonomous), Salem 636 007, Tamilnadu (India)

    2015-09-08

    Highlights: • Organic salt of 2-chloro-4-nitrobenzoate–3-ammonium-phenol (CNBA{sup −} · AP{sup +}) was grown by solution growth technique. • Single crystal X-ray diffraction demonstrate that two molecules were linked via N{sup +}–H⋯O{sup −} interactions. • The narrow spatial overlap between HOMO and LUMO leads to low ΔE{sub ST} = 73 meV. • The fluorescence emission was observed at ≈338 nm with Stokes shift of 53 nm. • The melting point of CNBA{sup −} · AP{sup +} is 187 °C which is higher than the individual components. - Abstract: Organic salt 2-chloro-4-nitrobenzoate (CNBA{sup −}) 3-ammonium-phenol (AP{sup +}) exhibits fluorescence at 338 nm in solution and frontier molecular orbitals generated from TDDFT calculations indicate that the ground state and the excited state are physically separated on AP{sup +} and CNBA{sup −}. The crystal structure and physical–chemical properties of the CNBA{sup −} · AP{sup +} were investigated using X-ray single crystal and powder diffraction, SEM, FTIR, UV–Vis–NIR, and fluorescence spectrometry. X-ray diffraction demonstrates that the two molecules are linked via N{sup +}–H⋯O{sup −} ammonium–carboxylate interactions, as expected considering their interaction propensities. Proton transfer has been confirmed by FTIR analysis. The melting point of CNBA{sup −} · AP{sup +} was observed at 186 °C, which is higher than pure CNBA (140 °C) or AP (120 °C). The observation of a spatially separated HOMO and LUMO possessing a narrow ΔE{sub ST} = 73.3 meV and an emission in the blue region is promising as an alternative method for the production of OLED materials.

  8. Effect of a Novel Quaternary Ammonium Methacrylate Polymer (QAMP on Adhesion and Antibacterial Properties of Dental Adhesives

    Directory of Open Access Journals (Sweden)

    Yasmine M. Pupo

    2014-05-01

    Full Text Available This study investigated the resin–dentin bond strength (μTBS, degree of conversion (DC, and antibacterial potential of an innovative adhesive system containing a quaternary ammonium methacrylate polymer (QAMP using in situ and in vitro assays. Forty-two human third molars were flattened until the dentin was exposed and were randomly distributed into three groups of self-etching adhesive systems: Clearfil™ SE Bond containing 5% QAMP (experimental group, Clearfil™ Protect Bond (positive control and Clearfil™ SE Bond (negative control. After light curing, three 1 mm-increments of composite resin were bonded to each dentin surface. A total of thirty of these bonded teeth (10 teeth per group was sectioned to obtain stick-shaped specimens and tested under tensile stress immediately, and after 6 and 12 months of storage in distilled water. Twelve bonded teeth (4 teeth per group were longitudinally sectioned in a mesio-to-distal direction to obtain resin-bonded dentin slabs. In situ DC was evaluated by micro-Raman spectroscopy. In vitro DC of thin films of each adhesive system was measured using Fourier transform infrared spectroscopy. In vitro susceptibility tests of these three adhesive systems were performed by the minimum inhibitory/minimum bactericidal concentration (MIC/MBC assays against Streptococcus mutans, Lactobacillus casei, and Actinomyces naeslundii. No statistically significant difference in μTBS was observed between Clearfil™ SE Bond containing 5% QAMP and Clearfil™ SE Bond (p > 0.05 immediately, and after 6 and 12 months of water storage. However Clearfil™ Protect Bond showed a significant reduction of μTBS after 12 months of storage (p = 0.039. In addition, QAMP provided no significant change in DC after incorporating into Clearfil™ SE Bond (p > 0.05. Clearfil™ SE Bond containing 5% QAMP demonstrated MIC/MBC values similar to the positive control against L. casei and A. naeslundii and higher than the negative

  9. Effect of a novel quaternary ammonium methacrylate polymer (QAMP) on adhesion and antibacterial properties of dental adhesives.

    Science.gov (United States)

    Pupo, Yasmine M; Farago, Paulo Vitor; Nadal, Jessica M; Simão, Luzia C; Esmerino, Luís Antônio; Gomes, Osnara M M; Gomes, João Carlos

    2014-05-20

    This study investigated the resin-dentin bond strength (μTBS), degree of conversion (DC), and antibacterial potential of an innovative adhesive system containing a quaternary ammonium methacrylate polymer (QAMP) using in situ and in vitro assays. Forty-two human third molars were flattened until the dentin was exposed and were randomly distributed into three groups of self-etching adhesive systems: Clearfil™ SE Bond containing 5% QAMP (experimental group), Clearfil™ Protect Bond (positive control) and Clearfil™ SE Bond (negative control). After light curing, three 1 mm-increments of composite resin were bonded to each dentin surface. A total of thirty of these bonded teeth (10 teeth per group) was sectioned to obtain stick-shaped specimens and tested under tensile stress immediately, and after 6 and 12 months of storage in distilled water. Twelve bonded teeth (4 teeth per group) were longitudinally sectioned in a mesio-to-distal direction to obtain resin-bonded dentin slabs. In situ DC was evaluated by micro-Raman spectroscopy. In vitro DC of thin films of each adhesive system was measured using Fourier transform infrared spectroscopy. In vitro susceptibility tests of these three adhesive systems were performed by the minimum inhibitory/minimum bactericidal concentration (MIC/MBC) assays against Streptococcus mutans, Lactobacillus casei, and Actinomyces naeslundii. No statistically significant difference in μTBS was observed between Clearfil™ SE Bond containing 5% QAMP and Clearfil™ SE Bond (p>0.05) immediately, and after 6 and 12 months of water storage. However Clearfil™ Protect Bond showed a significant reduction of μTBS after 12 months of storage (p=0.039). In addition, QAMP provided no significant change in DC after incorporating into Clearfil™ SE Bond (p>0.05). Clearfil™ SE Bond containing 5% QAMP demonstrated MIC/MBC values similar to the positive control against L. casei and A. naeslundii and higher than the negative control for all

  10. Three-dimensional low symmetry mesoporous silica structures templated from tetra-headgroup rigid bolaform quaternary ammonium surfactant.

    Science.gov (United States)

    Shen, Shaodian; Garcia-Bennett, Alfonso E; Liu, Zheng; Lu, Qingyi; Shi, Yifeng; Yan, Yan; Yu, Chengzhong; Liu, Weichang; Cai, Ya; Terasaki, Osamu; Zhao, Dongyuan

    2005-05-11

    Two kinds of highly ordered mesoporous silica materials (FDU-11, FDU-13) with novel three-dimensional (3-D) tetragonal and orthorhombic structures were synthesized by using tetra-headgroup rigid bolaform quaternary ammonium surfactant [(CH(3))(3)NCH(2)CH(2)CH(2)N(CH(3))(2)CH(2)(CH(2))(11)OC(6)H(4)C(6)H(4)O(CH(2))(11)CH(2)N(CH(3))(2)CH(2)CH(2)CH(2)N(CH(3))(3).4Br] (C(3-12-12)(-)(3)) as a template under alkaline conditions. High-resolution transmission electron microscopy (HRTEM), small-angle X-ray scattering (SAXS), and X-ray diffraction (XRD) show that mesoporous silica FDU-11 has primitive tetragonal P4/mmm structure with cell parameters a = b = 8.46 nm, c = 5.22 nm, and c/a ratio = 0.617. N(2) sorption isotherms show that calcined FDU-11 has a high BET surface area of approximately 1490 m(2)/g, a uniform pore size of approximately 2.72 nm, and a pore volume of approximately 1.88 cm(3)/g. Mesoporous silica FDU-13 has primitive orthorhombic Pmmm structure. The cell parameters are a = 9.81, b = 5.67, and c = 3.66 nm. N(2) sorption isotherms show that calcined FDU-13 has a high BET surface area of 1210 m(2)/g, a uniform mesopore size of approximately 1.76 nm, and a large pore volume of approximately 1.83 cm(3)/g. Such low symmetries for 3-D mesostructures (tetragonal and orthorhombic system) have not been observed before even in amphiphilic liquid crystals, which maybe resulted from an oblate aggregation of the bolaform surfactant and its strong electrostatic interaction with inorganic precursor. A probable mechanism has been proposed for the formation of such a 3-D low symmetrical mesostructure. These results will further extend the synthesis of mesoporous materials and may open up new opportunities for their new applications in catalysis, separation, and nanoscience.

  11. Poly(vinyl alcohol) composite films with high percent elongation prepared from amylose-fatty ammonium salt inclusion complexes

    Science.gov (United States)

    Amylose inclusion complexes prepared from cationic fatty ammonium salts and jet-cooked high amylose starch were combined with poly(vinyl alcohol) (PVOH) to form glycerol-plasticized films. Their tensile properties were compared with similar films prepared previously with analogous anionic fatty acid...

  12. Biocidal quaternary ammonium resin

    Science.gov (United States)

    Janauer, G. E.

    1983-01-01

    Activated carbon (charcoal) and polymeric resin sorbents are widely used in the filtration and treatment of drinking water, mainly to remove dissolved organic and inorganic impurities and to improve the taste. Earlier hopes that activated carbon might "disinfect' water proved to be unfounded. The feasibility of protecting against microbial infestation in charcoal and resin beds such as those to be incorporated into total water reuse systems in spacecraft was investigated. The biocidal effect of IPCD (insoluable polymeric contact disinfectants) in combination with a representative charcoal was assessed. The ion exchange resins (IPCD) were shown to adequately protect charcoal and ion exchange beds.

  13. Chemical, biochemical, and microbiological aspects of chitosan quaternary salt as active coating on sliced apples

    Directory of Open Access Journals (Sweden)

    Douglas de Britto

    2012-09-01

    Full Text Available The biocompatibility of chitosan and chitosan quaternary salt coatings was evaluated for use as edible coatings for sliced apple. Measurement of water loss, color change, and fungal growth appearance were monitored as a function of time. A significant brownish effect was observed on chitosan coated slices, varying greatly from L* = 76.5 and Hue angle = 95.9° (t = 0 to L* = 45.3 and Hue angle = 69.8° (t = 3 days, whilst for TMC coated samples the variation was considerable lower (L* = 74.1; Hue angle = 95.0° to (L* = 67.0; Hue angle = 83.8° within the same period. The hydrosoluble derivative N,N,N-trimethylchitosan demonstrated good antifungal activity against P. expansum although highly dependent on the polymer properties such as degree of quaternization. The most efficient formulation was that prepared from derivative having a degree of quaternization of 45%, high solubility, and high viscosity. This formulation restrained fungus spreading up to 30%, while for the control it reached almost 80% of the total assessed surfaces during 7 days of storage.

  14. Cycloaddition Reaction of Carbon Dioxide to Epoxides Catalyzed by Polymer-Supported Quaternary Phosphonium Salts

    Directory of Open Access Journals (Sweden)

    Yubing Xiong

    2013-01-01

    Full Text Available Polymer-supported quaternary phosphonium salt (PS-QPS was explored as effective catalyst for the coupling reaction of carbon dioxide with epoxides. The results indicated that cyclic carbonates with high yields (98.6% and excellent selectivity (100% could be prepared at the conditions of 5 MPa CO2, 150°C, and 6 h without the addition of organic solvents or cocatalysts. The effects of various reaction conditions on the catalytic performance were investigated in detail. The catalyst is applicable to a variety of epoxides, producing the corresponding cyclic carbonates in good yields. Furthermore, the catalyst could be recovered easily and reused for five times without loss of catalytic activity obviously. A proposed mechanism for synthesis of cyclic carbonate in the presence of PS-QPS was discussed. The catalyst was characterized by thermogravimetric analysis (TGA, scanning electron microscopy (SEM, and Fourier transform infrared (FT-IR spectrum. It is believed that PS-QPS is of great potential for CO2 fixation applications due to its unusual advantages, such as easy preparation, high activity and selectivity, stability, low cost, and reusability.

  15. 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)

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

    Science.gov (United States)

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

    2016-11-01

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

  17. 季铵化溶胶稳定性影响因素及其抗菌性能%Factors affecting stability and antibacterial properties of quaternary ammonium sol

    Institute of Scientific and Technical Information of China (English)

    王学鑫; 王潮霞

    2009-01-01

    为改善棉织物的抗菌性能,采用溶胶-凝胶法将季铵盐整理到织物表面.以正硅酸乙酯、乙醇为原料,盐酸为催化剂,季铵盐为添加剂制备阳离子季铵化溶胶.探讨酸、水、溶剂乙醇与前驱体正硅酸乙酯的物质的量比和反应温度对阳离子溶胶稳定性的影响.结果表明:盐酸用量增大,反应温度升高,溶胶的黏度增大,离心稳定性降低;随着体系水量的增加,溶胶的黏度先增大后减小,离心稳定性先降低后升高;乙醇用量增大,溶胶的黏度降低,离心稳定性提高.经溶胶整理后的织物对金黄色葡萄球菌表现出良好的杀菌性能且具有较好的耐水洗性.%The cotton fabric was treated with quaternary ammonium salt by sol-gel method in order to improve its antibacterial property.Cationic quaternized sol was synthesized from tetraethoxysilane (TEOS),ethanol with hydrochloric acid as catalyst and quaternary ammonium salt as additive.The effects of the ratio of acid,water,solvent ethanol and TEOS,and reaction temperature on the stability of cationic sol were studied.The results showed that the increase of the acid concentration and temperature increased the viscosity of the sol and decreased its centrifugal stability.With the increase of water in the system,the viscosity of the sol firstly increased and then decreased,while the centrifugal stability firstly droped and then rose.The viscosity of the sol decreased and the centrifugal stability increased considerably with increasing of the amount of ethanol.The fabric treated with the sol showed good antibacterial activity against Escherichia coli and also remained good antibacterial effect after many washing cycles.

  18. Impact of hydrotreaters ammonium chloride salt deposition of refinery operations; Formacao de depositos de sais de amonio em Unidades de Hidrotramento (HDT'S)

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Nelmo Furtado; Cunha, Fabiana A.; Alvise, Paulo Pio [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    Fouling and consequent under deposit corrosion caused by ammonium salts, especially ammonium chloride, have serious impact on the reliability of operation of various process units. In hydrotreating units salt deposition on heat exchanger tubes causes a decrease in heat transfer efficiency, decrease hydrotreating efficiency, increased pressure drops, and corrosion. This paper will discuss the causes of ammonium chloride fouling,methods to help prevent and/or mitigate the fouling, and provide a case history demonstrating the effects of ammonium chloride formations in one refinery operation. (author)

  19. New Diethyl Ammonium Salt of Thiobarbituric Acid Derivative: Synthesis, Molecular Structure Investigations and Docking Studies

    Directory of Open Access Journals (Sweden)

    Assem Barakat

    2015-11-01

    Full Text Available The synthesis of the new diethyl ammonium salt of diethylammonium(E-5-(1,5-bis(4-fluorophenyl-3-oxopent-4-en-1-yl-1,3-diethyl-4,6-dioxo-2-thioxohexaydropyrimidin-5-ide 3 via a regioselective Michael addition of N,N-diethylthiobarbituric acid 1 to dienone 2 is described. In 3, the carboanion of the thiobarbituric moiety is stabilized by the strong intramolecular electron delocalization with the adjacent carbonyl groups and so the reaction proceeds without any cyclization. The molecular structure investigations of 3 were determined by single-crystal X-ray diffraction as well as DFT computations. The theoretically calculated (DFT/B3LYP geometry agrees well with the crystallographic data. The effect of fluorine replacement by chlorine atoms on the molecular structure aspects were investigated using DFT methods. Calculated electronic spectra showed a bathochromic shift of the π-π* transition when fluorine is replaced by chlorine. Charge decomposition analyses were performed to study possible interaction between the different fragments in the studied systems. Molecular docking simulations examining the inhibitory nature of the compound show an anti-diabetic activity with Pa (probability of activity value of 0.229.

  20. Direct Aqueous Mineral Carbonation of Waste Slate Using Ammonium Salt Solutions

    Directory of Open Access Journals (Sweden)

    Hwanju Jo

    2015-12-01

    Full Text Available The carbonation of asbestos-containing waste slate using a direct aqueous mineral carbonation method was evaluated. Leaching and carbonation tests were conducted on asbestos-containing waste slate using ammonium salt (CH3COONH4, NH4NO3, and NH4HSO4 solutions at various concentrations. The CH3COONH4 solution had the highest Ca-leaching efficiency (17%–35% and the NH4HSO4 solution had the highest Mg-leaching efficiency (7%–24% at various solid dosages and solvent concentrations. The CaCO3 content of the reacted materials based on thermogravimetric analysis (TGA was approximately 10%–17% higher than that of the as-received material for the 1 M CH3COONH4 and the 1 M NH4HSO4 solutions. The carbonates were precipitated on the surface of chrysotile, which was contained in the waste slate reacted with CO2. These results imply that CO2 can be sequestered by a direct aqueous mineral carbonation using waste slate.

  1. Influence of the ammonium salt anion on the synergistic solvent extraction of lanthanides with mixtures of thenoyltrifluoroacetone and tridecylamine

    Energy Technology Data Exchange (ETDEWEB)

    Dukov, I.L.; Jordanov, V.M. [Univ. of Chemical Technology and Metallurgy, Sofia (Bulgaria). Dept. of Inorganic Chemistry

    1998-08-01

    The synergistic solvent extraction of Pr, Gd and Yb with mixtures of thenoyltrifluoroacetone (HTTA) and primary ammonium salt (tridecylammonium chloride or perchlorate, TDAH(Cl, ClO{sub 4})) in C{sub 6}H{sub 6} has been studied. The composition of the extracted species have been determined as Ln(TTA){sub 3}TDAHA(A{sup {minus}} = Cl{sup {minus}} or ClO{sub 4}{sup {minus}}). The values of the equilibrium constant K{sub T,S} have been calculated. The influence of the ammonium salt anion on the extraction process has been discussed. The separation factors of the pairs Gd/Pr and Yb/Gd have been determined.

  2. Aging Effects on the Properties of Imidazolium-, Quaternary Ammonium-, Pyridinium-, and Pyrrolidinium-Based Ionic Liquids Used in Fuel and Energy Production

    Energy Technology Data Exchange (ETDEWEB)

    Fox, Elise B.; Smith, L. Taylor; Williamson, Tyler K.; Kendrick, Sarah E.

    2013-11-21

    Ionic liquids (ILs) are often cited for their excellent thermal stability, a key property for their use as solvents and in the chemical processing of biofuels. However, there has been little supporting data on the long-term aging effect of the temperature on these materials. Imizadolium-, quaternary ammonium-, pyridinium-, and pyrrolidnium-based ILs with the bis(trifluoromethylsulfonyl)imide and bis(perfluoroethylsulfonyl)imide anions were aged for 2520 h (15 weeks) at 200 °C in air to determine the effects of an oxidizing environment on their chemical structure and thermal stability over time. Finally, it was found that the minor changes in the cation chemistry could greatly affect the properties of the ILs over time.

  3. Optimizing the concentration of quaternary ammonium dimethacrylate monomer in bis-GMA/TEGDMA dental resin system for antibacterial activity and mechanical properties.

    Science.gov (United States)

    Liang, Xiaoxu; Söderling, Eva; Liu, Fang; He, Jingwei; Lassila, Lippo V J; Vallittu, Pekka K

    2014-05-01

    Four novel quaternary ammonium dimethacrylate monomers named IMQ (side alkyl chain length from 12 to 18) were synthesized with the aim to synthesize dental resin with antibacterial activity. All of IMQs were added into bis-GMA/TEGDMA dental resin system with a series of mass ratio (5, 10, and 20 wt%), double bond conversion (DC), flexural strength (FS), modulus of elasticity (FM) and biofilm formation inhibitory effect were studied. According to the results of DC, FS, FM, and the biofilm inhibitory effect, IMQ-16 containing polymer had the best comprehensive properties, and the optimal concentration of IMQ-16 in bis-GMA/TEGDMA dental resin would be in the range of 5-10 wt%.

  4. Synthesis of linear [5]catenanes via olefin metathesis dimerization of pseudorotaxanes composed of a [2]catenane and a secondary ammonium salt.

    Science.gov (United States)

    Iwamoto, Hajime; Tafuku, Shinji; Sato, Yoshihiko; Takizawa, Wataru; Katagiri, Wataru; Tayama, Eiji; Hasegawa, Eietsu; Fukazawa, Yoshimasa; Haino, Takeharu

    2016-01-01

    [5]Catenanes were synthesized by olefin metathesis dimerization. The reaction of pseudorotaxanes, which were derived from a [2]catenane and one equivalent of an ammonium salt bearing two terminal olefins in dichloromethane, with a catalytic amount of Grubbs catalyst afforded linear [5]catenanes in 12% yield. Intermolecular and intramolecular olefin metathesis reactions were controlled by the length of the alkyl chain of the ammonium salts.

  5. Catalyst used in 1,2-epoxyalkane preparation is obtained by heating tetraalkyl ammonium salts, tetraalkyl siloxanes and amines, calcining and treating with a tetraalkoxy compound

    DEFF Research Database (Denmark)

    2001-01-01

    NOVELTY - The catalyst, used in 1,2-epoxyalkane preparation, is obtained by heat treating an aqueous composition comprising tetraalkyl ammonium salts, tetraalkyl siloxanes and amines, removing the template by calcining and treating with a tetraalkoxy compound......NOVELTY - The catalyst, used in 1,2-epoxyalkane preparation, is obtained by heat treating an aqueous composition comprising tetraalkyl ammonium salts, tetraalkyl siloxanes and amines, removing the template by calcining and treating with a tetraalkoxy compound...

  6. EMERGENCE, GROWTH AND PRODUCTION OF SESAME UNDER SALT STRESS AND PROPORTIONS OF NITRATE AND AMMONIUM

    Directory of Open Access Journals (Sweden)

    ADAAN SUDARIO DIAS

    2017-01-01

    Full Text Available In arid and semi - arid regions, the quality of irrigation water varies in geographic terms and during the year, and the occurrence of water with high concentrations of salts is common. In this context, this study aimed to evaluate the emergence, growth and production of sesame, cultivar CNPA G3, irrigated with saline water and fertilized with N of different carrier proportions by the ratio of nitrate and ammonium ( NO 3 - - N and NH 4 + - N in an experiment conducted in lysimeters arranged in a greenhouse in the municipality of Campina Grande - PB, Brazil. The treatments were distributed into randomized blocks using a 5 × 5 factorial scheme relative to levels of irrigation water salinity (ECw; 0.6, 1.2, 1.8, 2.4 and 3.0 dS m - 1 and five proportions of NO 3 - - N/NH 4 + - N (200/0; 150/50; 100/100; 50/150 and 0/200 mg of N kg - 1 , with three replicates. The increase in ECw compromised the emergence, growth and production of sesame, cultivar CNPA G3, and the production components were the most sensitive variables. The highest growth in diameter was obtained with the proportion of 200/0 mg kg - 1 of NO 3 - - N /NH 4 + - N . An ECw level of 3.0 dS m - 1 and fertilization with 0/200 mg kg - 1 of NO 3 - - N /NH 4 + - N promoted deleterious effects on the total mass of sesame fruits and mass of seeds. The interaction between water salinity levels and NO 3 - /NH 4 + proportions significantly affected the number of leaves (at 50 and 70 days after sowing, the total mass of fruits and the mass of seeds.

  7. Synthesis and antimicrobial activity of chiral quaternary N-spiro ammonium bromides with 3',4'-dihydro-1'H-spiro[isoindoline-2,2'-isoquinoline] skeleton

    Directory of Open Access Journals (Sweden)

    Bielawski K

    2017-07-01

    Full Text Available Krzysztof Bielawski,1 Katarzyna Leszczyńska,2 Zbigniew Kałuża,3 Anna Bielawska,4 Olga Michalak,3 Tamara Daniluk,2 Olga Staszewska-Krajewska,3 Anna Czajkowska,4 Natalia Pawłowska,1 Agnieszka Gornowicz4 1Department of Synthesis and Technology of Drugs, 2Department of Microbiology, Medical University of Bialystok, Bialystok, 3Institute of Organic Chemistry, Polish Academy of Sciences, Warsaw, 4Department of Biotechnology, Medical University of Bialystok, Bialystok, Poland Abstract: A new class of highly functionalized tetrahydroisoquinolines with a quaternary carbon stereocenter was synthesized starting from an easily accessible l-tartaric acid. Nine strains of bacteria (Staphylococcus aureus, Streptococcus pyogenes, Streptococcus mutans, Streptococcus salivarius, Bacillus subtilis, Enterococcus faecalis, Moraxella catarrhalis, Escherichia coli, Campylobacter jejuni were used for the determination of minimal inhibitory concentration (MIC and minimal bactericidal concentration (MBC of synthesized compounds. The influence of analyzed compounds on viability and induction of apoptosis in human skin fibroblasts was determined. A majority of the synthesized compounds showed the strongest antibacterial properties toward some gram-negative bacteria (M. catarrhalis and C. jejuni with a high level of selectivity. High antibacterial compounds have bactericidal activity ratio MBC/MIC =4. Our studies also proved that the novel compounds do not possess cytotoxic and proapoptotic potential in normal cells. Keywords: quaternary ammonium compounds, tetrahydroisoquinolines, antimicrobial activity, antibiotic resistance 

  8. A systematic investigation of quaternary ammonium ions as asymmetric phase-transfer catalysts. Application of quantitative structure activity/selectivity relationships.

    Science.gov (United States)

    Denmark, Scott E; Gould, Nathan D; Wolf, Larry M

    2011-06-01

    Although the synthetic utility of asymmetric phase-transfer catalysis continues to expand, the number of proven catalyst types and design criteria remains limited. At the origin of this scarcity is a lack in understanding of how catalyst structural features affect the rate and enantioselectivity of phase transfer catalyzed reactions. Described in this paper is the development of quantitative structure-activity relationships (QSAR) and -selectivity relationships (QSSR) for the alkylation of a protected glycine imine with libraries of quaternary ammonium ion catalysts. Catalyst descriptors including ammonium ion accessibility, interfacial adsorption affinity, and partition coefficient were found to correlate meaningfully with catalyst activity. The physical nature of the descriptors was rationalized through differing contributions of the interfacial and extraction mechanisms to the reaction under study. The variation in the observed enantioselectivity was rationalized employing a comparative molecular field analysis (CoMFA) using both the steric and electrostatic fields of the catalysts. A qualitative analysis of the developed model reveals preferred regions for catalyst binding to afford both configurations of the alkylated product.

  9. Synthesis, photophysical and antimicrobial activity of new water soluble ammonium quaternary benzanthrone in solution and in polylactide film.

    Science.gov (United States)

    Staneva, Desislava; Vasileva-Tonkova, Evgenia; Makki, Mohamad Saleh I; Sobahi, Tariq Rashad; Abdеl-Rahman, Reda Mohamed; Asiri, Abdullah M; Grabchev, Ivo

    2015-02-01

    The synthesis of a new cationic water soluble fluorescent 1-[(7-oxo-7H-benzo[de]anthracen-3-ylcarbamoyl)-methyl]-triethylammonium chloride (B) has been described. Due to the presence of the quaternary amino group, the compound is soluble in water. Its photophysical characteristics in aqueous solution and organic solvents with different polarity have been determined using absorption and fluorescence spectroscopy. The photostability of compound B has been investigated in aqueous media. The newly synthesized compound has been tested in vitro for its antimicrobial activity against eight bacterial and two yeasts cultures. The results obtained suggest that the newly synthesized compound is effective in treating the relevant pathogens and is suitable in designing new effective antimicrobial preparations. The incorporation of the compound into thin polylactic acid film and its release into water solution has been also investigated. It was demonstrated that the compound released from the polymer polylactic acid matrix exhibited a prolonged good antibacterial activity. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. 一种双链复合季铵盐手消毒液消毒效果现场试验研究%FIELD TRIAL ON GERMICIDAL EFFICACY OF A DOUBLE-CHAIN QUATERNARY AMMONIUM CONPOUNDS HAND ANTISEPTIC AGENT

    Institute of Scientific and Technical Information of China (English)

    周炯; 李桂萍; 马小军

    2013-01-01

    Objective To evaluate the field disinfection efficacy on hands of a double - chain quaternary ammonium compounds, in order to provide the basis for clinical disinfection work. Methods The hands disinfection field trial was used to observe hands disinfection effect of double- chain quaternary ammonium compounds on 30 volunteers. Results After 2 min spray and lmin wipe disinfection using double - chain quaternary ammonium compounds on hands and forearm skin, the average killing rate of natural bacteria was 96.63%. Conclusion This double - chain quaternary ammonium compound has good germicidal effect on natural bacteria and has no skin irritation.%目的 评价一种双链复合季铵盐手消毒液现场消毒效果,为临床消毒实际应用提供依据.方法 采用现场消毒试验方法,对医院自愿受试者手进行现场消毒效果观察.结果 用该复合季铵盐消毒液在手和前臂皮肤上喷洒湿润作用2 min,再用该消毒液擦拭1 min,对皮肤上自然菌平均清除率为96.63%.结论 该双链复合季铵盐手消毒液对医务人员手上自然菌具有良好的消毒效果,对皮肤无刺激性.

  11. Simultaneous ammonium and phosphate removal by metal inorganic salt modification of natural zeolite

    OpenAIRE

    Ventosa i Capell, Blanca

    2015-01-01

    Nutrients discharge into receiving waters can cause an environmental problem capable of deathly altering ecosystems. Natural zeolites are low cost resources with ion exchange capacity that have been widely studied. This study deals with simultaneous adsorption of nutrients; viz. ammonium and phosphate, onto different modifications of natural zeolite, clinoptilolite. Research has been focused on the optimization of surface modification procedures to raise clinoptilolite efficien...

  12. Nickel-Catalyzed Cross Couplings of Benzylic Ammonium Salts and Boronic Acids: Stereospecific Formation of Diarylethanes via C–N Bond Activation

    Science.gov (United States)

    Maity, Prantik; Shacklady-McAtee, Danielle M.; Yap, Glenn P. A.; Sirianni, Eric R.; Watson, Mary P.

    2014-01-01

    We have developed a nickel-catalyzed cross coupling of benzylic ammonium triflates with aryl boronic acids to afford diarylmethanes and diarylethanes. This reaction proceeds under mild reaction conditions and with exceptional functional group tolerance. Further, it transforms branched benzylic ammonium salts to diarylethanes with excellent chirality transfer, offering a new strategy for the synthesis of highly enantioenriched diarylethanes from readily available chiral benzylic amines. PMID:23268734

  13. Novel quaternary ammonium microblock poly (p-phenylene-co-aryl ether ketone)s as anion exchange membranes for alkaline fuel cells

    Science.gov (United States)

    Dong, Xue; Xue, Boxin; Qian, Huidong; Zheng, Jifu; Li, Shenghai; Zhang, Suobo

    2017-02-01

    Using cation compounds as raw materials, three quaternized microblock poly(p-phenylene-co-aryl ether ketone)s (s-, m-, and l-QPP-co-PAEK) were synthesized using a nickel (0)-catalyzed coupling reaction. Hydrophilic and hydrophobic moieties were affixed using cationic quaternary ammonium (QA) groups attached to poly(p-phenylene) by a three-carbon interstitial spacer and nonionic dichloride monomers of various lengths, respectively. The morphology, water uptake, swelling ratio, mechanical properties, thermal stability, hydroxide conductivity and alkaline stability of these new membranes were investigated. Experimental results indicated that the membrane with the longest hydrophobic microblock exhibited high hydroxide conductivity (37.6 mS cm-1 at 80 °C) resulting from the aggregation of ionic clusters observed using TEM. The copolymers with longer hydrophobic nonionic segments exhibited improved alkaline stability, suggesting that the hydrophobic chain shields the QA groups and that the polymer chains pack in a manner that restricts rotation. Controlling the distribution of QA groups in poly(p-phenylene) moieties and tuning the block length of nonionic segments are demonstrated to be effective methods for improving the hydroxide conductivity and alkaline stability of anion exchange membranes.

  14. Quaternary ammonium oxidative demethylation: X-ray crystallographic, resonance Raman, and UV-visible spectroscopic analysis of a Rieske-type demethylase.

    Science.gov (United States)

    Daughtry, Kelly D; Xiao, Youli; Stoner-Ma, Deborah; Cho, Eunsun; Orville, Allen M; Liu, Pinghua; Allen, Karen N

    2012-02-08

    Herein, the structure resulting from in situ turnover in a chemically challenging quaternary ammonium oxidative demethylation reaction was captured via crystallographic analysis and analyzed via single-crystal spectroscopy. Crystal structures were determined for the Rieske-type monooxygenase, stachydrine demethylase, in the unliganded state (at 1.6 Å resolution) and in the product complex (at 2.2 Å resolution). The ligand complex was obtained from enzyme aerobically cocrystallized with the substrate stachydrine (N,N-dimethylproline). The ligand electron density in the complex was interpreted as proline, generated within the active site at 100 K by the absorption of X-ray photon energy and two consecutive demethylation cycles. The oxidation state of the Rieske iron-sulfur cluster was characterized by UV-visible spectroscopy throughout X-ray data collection in conjunction with resonance Raman spectra collected before and after diffraction data. Shifts in the absorption band wavelength and intensity as a function of absorbed X-ray dose demonstrated that the Rieske center was reduced by solvated electrons generated by X-ray photons; the kinetics of the reduction process differed dramatically for the liganded complex compared to unliganded demethylase, which may correspond to the observed turnover in the crystal.

  15. Ion distribution in quaternary-ammonium-functionalized aromatic polymers: effects on the ionic clustering and conductivity of anion-exchange membranes.

    Science.gov (United States)

    Weiber, E Annika; Jannasch, Patric

    2014-09-01

    A series of copoly(arylene ether sulfone)s that have precisely two, three, or four quaternary ammonium (QA) groups clustered directly on single phenylene rings along the backbone are studied as anion-exchange membranes. The copolymers are synthesized by condensation polymerizations that involve either di-, tri-, or tetramethylhydroquinone followed by virtually complete benzylic bromination using N-bromosuccinimide and quaternization with trimethylamine. This synthetic strategy allows excellent control and systematic variation of the local density and distribution of QA groups along the backbone. Small-angle X-ray scattering of these copolymers shows extensive ionic clustering, promoted by an increasing density of QA on the single phenylene rings. At an ion-exchange capacity (IEC) of 2.1 meq g(-1), the water uptake decreases with the increasing local density of QA groups. Moreover, at moderate IECs at 20 °C, the Br(-) conductivity of the densely functionalized copolymers is higher than a corresponding randomly functionalized polymer, despite the significantly higher water uptake of the latter. Thus, the location of multiple cations on single aromatic rings in the polymers facilitates the formation of a distinct percolating hydrophilic phase domain with a high ionic concentration to promote efficient anion transport, despite probable limitations by reduced ion dissociation. These findings imply a viable strategy to improve the performance of alkaline membrane fuel cells.

  16. Bifunctional quaternary ammonium compounds to inhibit biofilm growth and enhance performance for activated carbon air-cathode in microbial fuel cells

    Science.gov (United States)

    Li, Nan; Liu, Yinan; An, Jingkun; Feng, Cuijuan; Wang, Xin

    2014-12-01

    The slow diffusion of hydroxyl out of the catalyst layer as well as the biofouling on the surface of cathode are two problems affecting power for membrane-less air-cathode microbial fuel cells (MFCs). In order to solve both of them simultaneously, here we simply modify activated carbon air-cathode using a bifunctional quaternary ammonium compound (QAC) by forced evaporation. The maximum power density reaches 1041 ± 12 mW m-2 in an unbuffered medium (0.5 g L-1 NaCl), which is 17% higher than the control, probably due to the accelerated anion transport in the catalyst layer. After 2 months, the protein content reduced by a factor of 26 and the power density increases by 33%, indicating that the QAC modification can effectively inhibit the growth of cathodic biofilm and improve the stability of performance. The addition of NaOH and QAC epoxy have a negative effect on power production due to the clogging of pores in catalyst layer.

  17. Study of the activity of quaternary ammonium compounds in the mitigation of biofouling in heat exchangers-condensers cooled by seawater.

    Science.gov (United States)

    Trueba, Alfredo; Otero, Félix M; González, José A; Vega, Luis M; García, Sergio

    2013-01-01

    The effectiveness of two quaternary ammonium compounds (QACs) (non-oxidising biocides) to reduce the growth of biofilm adhering to the tubes of a heat exchanger-condenser cooled by seawater was evaluated. Their effectiveness was compared to that of a conventional oxidising biocide (sodium hypochlorite [NaOCl]) under the same testing conditions. Each biocide was applied intermittently (6 h on, 6 h off) in a first shock stage (1.5 ppm over 8 days) and a second stabilising stage (0.5 ppm over 20 days). The results showed that the antifouling effectiveness of the first of the QACs (fifth generation) was comparable to that shown by the oxidising power of NaOCl. Although the reaction time was longer than that of NaOCl, both the compounds removed the biofilm, and the tube was practically restored to its clean condition. Treatment with the second of the QACs (fourth generation) allowed for the stabilisation of biofilm growth, but not for its removal. Ecotoxicology studies classified the QACs as environmentally harmless under the testing conditions.

  18. Evaluation of aqueous and alcohol-based quaternary ammonium sanitizers for inactivating Salmonella spp., Escherichia coli O157:H7, and Listeria monocytogenes on peanut and pistachio shells.

    Science.gov (United States)

    McEgan, Rachel; Danyluk, Michelle D

    2015-05-01

    This study evaluated the efficacy of aqueous (aQUAT) and isopropyl alcohol-based quaternary ammonium (ipQUAT) sanitizers for reducing Salmonella spp., Escherichia coli O157:H7, or Listeria monocytogenes populations on peanut and pistachio shell pieces. Inoculated nutshells were mixed with QUAT sanitizers, water, or 70% ethanol and enumerated immediately or after incubation at 30 °C for 48 h. None of the treatments had any immediate effect on Salmonella or E. coli O157:H7 populations on the peanut or pistachio shells. L. monocytogenes populations declined immediately on the peanut and pistachio shells treated with aQUAT or ipQUAT. After incubation, Salmonella and E. coli O157:H7 populations increased significantly on the water- or aQUAT-treated peanut and pistachio shells. L. monocytogenes populations also increased significantly on the water- or aQUAT-treated peanut shells, but levels did not change on the water-treated pistachio shells and levels were just above the limit of detection on the aQUAT-treated pistachio shells. After treatment with ipQUAT and 48-h incubation, Salmonella and E. coli O157:H7 populations decreased to or below the limit of detection on both shell types; L. monocytogenes populations remained at or below the limit of detection on both shell types.

  19. One-pot synthesis of cyclic aldol tetramer and,β-unsaturated aldol from linear aldehydes using quaternary ammonium combined with sodium hydroxide as catalysts

    Institute of Scientific and Technical Information of China (English)

    许海峰; 钟宏; 王帅; 李方旭

    2015-01-01

    One-pot synthesis of cyclic aldol tetramer anda,β-unsaturated aldol from C3−C8 linear aldehydes using phase-transfer catalyst (PTC), quaternary ammonium, combined with sodium hydroxide as catalysts was investigated. Butanal was subjected for detail investigations to study the effect of parameters. It was found that the selectivity of cyclic aldol tetramer depends greatly on the operating conditions of the reaction, especially the PTC/butanal molar ratio. The average selectivity of 2-hydroxy-6-propyl-l, 3, 5-triethyl-3-cyclohexene-1-carboxaldehyde (HPTECHCA) was 54.41% using tetrabutylammonium chloride combined with 14% (mass fraction) NaOH as catalysts at 60 °C for 2 h with a PTC-to-butanal molar ratio of 0.09:1. Pentanal was more likely to generate cyclic aldol tetramer compared with other aldehydes under the optimum experimental conditions. Recovery of the PTC through water washing followed by adding enough sodium hydroxide from the washings was also demonstrated.

  20. Kalahari salt pans as sedimentary archives for reconstruction of Quaternary environments

    Science.gov (United States)

    Schüller, Irka; Belz, Lukas; Wilkes, Heinz; Wehrmann, Achim

    2015-04-01

    Environmental changes in southern Africa come along with variations in atmospheric and oceanic circulation as well as anthropogenic caused landuse changes. The reconstruction of the paleoenvironment is complicated by the fact that continuous geoarchives are rare in the semiarid to arid parts of this region. In the south-western Kalahari lacustrine systems with constant sedimentary records are absent due to the low precipitation. Salt pans are common geomorphological structures in the Kalahari which are temporarily flooded during summer season when isolated showers occur in their local catchment area. So, they are potential archives preserving environmental signals in phases of sedimentation. However, marginal dunes on their leeward sides represent phases of deflation. The principle processes in salt pan formation are complex and so far under discussion. Our study follows a multidisciplinary approach integrating sedimentological, geochemical and microbiological methods to understand the formation of salt pans as a prerequisite for using them as geoarchives in reconstruction of the paleoenvironmental condition during phases of sedimentation and erosion. Sediment cores from five salt pans were analysed using XRD, XRF and grain size analyses. Additionally, age models can be given for four salt pans, based on δ14C from bulk sediment TOC. As palynological material is lacking, different methods in organic geochemistry were applied (plant biomarkers, particularly leaf wax n-alkanes and n-alcohols and their stable carbon and hydrogen isotopic signatures) to reconstruct variations in local vegetation assemblages. Our results allow a better understanding of the sedimentology of salt pans and their interpretation as discontinuous archives.

  1. Polymer-Supported Cinchona Alkaloid-Derived Ammonium Salts as Recoverable Phase-Transfer Catalysts for the Asymmetric Synthesis of α-Amino Acids

    Directory of Open Access Journals (Sweden)

    Carmen Nájera

    2004-04-01

    Full Text Available Alkaloids such as cinchonidine, quinine and N-methylephedrine have been N-alkylated using polymeric benzyl halides or co-polymerized and then N-alkylated, thus affording a series of polymer-supported chiral ammonium salts which have been employed as phase-transfer catalysts in the asymmetric benzylation of an N-(diphenylmethyleneglycine ester. These new polymeric catalysts can be easily recovered by simple filtration after the reaction and reused. The best ee’s were achieved when Merrifield resin-anchored cinchonidinium ammonium salts were employed.

  2. Effect of ammonium-salt solutions on the surface properties of carbon fibers in electrochemical anodic oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Qian Xin, E-mail: qx3023@nimte.ac.cn [National Engineering Laboratory of Carbon Fiber Preparation Technology, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Wang Xuefei; Ouyang Qin; Chen Yousi; Yan Qing [National Engineering Laboratory of Carbon Fiber Preparation Technology, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Longitudinal grooves on the fiber surface became more well-defined and much deeper after surface treatment. Black-Right-Pointing-Pointer The concentration of oxygen and nitrogen on the fiber surface increased after surface treatment. Black-Right-Pointing-Pointer The intensity of oxidative reaction varied with the change of ammonium-salt solutions. Black-Right-Pointing-Pointer The higher the concentration of OH{sup -} ions in the electrolytes, the violent the oxidative reaction happened. - Abstract: The surfaces of polyacrylonitrile-based carbon fibers were treated by an electrochemical anodic method. Three different kinds of ammonium-salt solutions namely NH{sub 4}HCO{sub 3}, (NH{sub 4}){sub 2}CO{sub 3} and (NH{sub 4}){sub 3}PO{sub 4} were respectively chosen as the electrolytes. The effect of these electrolytes on the surface structure was studied by scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). The results showed that longitudinal grooves on the fiber surface became more well-defined and much deeper after surface treatment, and the root mean square roughness (RMS) of carbon fiber surface increased from 4.6 nm for untreated fibers to 13.5 nm for treated fibers in (NH{sub 4}){sub 3}PO{sub 4} electrolytes. The concentration of oxygen and nitrogen atomic on the fiber surface increased after surface treatment. The tensile strength of oxidized fibers had an obvious decrease, whereas the interlaminar shear strength (ILSS) value of corresponding carbon fiber reinforced polymers (CFRPs) increased in a large extent. The intensity of oxidative reaction varied with the change of ammonium-salt solutions and electrochemical oxidation in (NH{sub 4}){sub 3}PO{sub 4} electrolyte was of the most violence. The corresponding mechanism was also discussed and the result showed that the higher the concentration of OH{sup -} ions in the electrolytes, the violent the oxidative

  3. Water- and organo-dispersible gold nanoparticles supported by using ammonium salts of hyperbranched polystyrene: preparation and catalysis.

    Science.gov (United States)

    Gao, Lei; Nishikata, Takashi; Kojima, Keisuke; Chikama, Katsumi; Nagashima, Hideo

    2013-12-01

    Gold nanoparticles (1 nm in size) stabilized by ammonium salts of hyperbranched polystyrene are prepared. Selection of the R groups provides access to both water- and organo-dispersible gold nanoparticles. The resulting gold nanoparticles are subjected to studies on catalysis in solution, which include reduction of 4-nitrophenol with sodium borohydride, aerobic oxidation of alcohols, and homocoupling of phenylboronic acid. In the reduction of 4-nitrophenol, the catalytic activity is clearly dependent on the size of the gold nanoparticles. For the aerobic oxidation of alcohols, two types of biphasic oxidation are achieved: one is the catalyst dispersing in the aqueous phase, whereas the other is in the organic phase. The catalysts are reusable more than four times without loss of the catalytic activity. Selective synthesis of biphenyl is achieved by the homocoupling of phenylboronic acid catalyzed by organo-dispersible gold nanoparticles.

  4. New multilayer coating using quaternary ammonium chitosan and κ-carrageenan in capillary electrophoresis: application in fast analysis of betaine and methionine.

    Science.gov (United States)

    Vitali, Luciano; Della Betta, Fabiana; Costa, Ana Carolina O; Vaz, Fernando Antonio Simas; Oliveira, Marcone Augusto Leal; Vistuba, Jacqueline Pereira; Fávere, Valfredo T; Micke, Gustavo A

    2014-06-01

    The aim of this study was to develop a new multilayer coating with crosslinked quaternary ammonium chitosan (hydroxypropyltrimethyl ammonium chloride chitosan; HACC) and κ-carrageenan for use in capillary electrophoresis. A new semi-permanent multilayer coating was formed using the procedure developed and the method does not require the presence of polymers in the background electrolyte (BGE). The new capillary multilayer coating showed a cathodic electroosmotic flow (EOF) of around 30×10(-9) m(2) V(-1) s(-1) which is pH-independent in the range of pH 2 to 10. The enhanced EOF at low pH obtained contributed significantly to the development of a fast method of separation. The multilayer coating was then applied in the development of a fast separation method to determine betaine and methionine in pharmaceutical formulations by capillary zone electrophoresis (CZE). The BGE used to determine the betaine and methionine concentrations was composed of 10 mmol L(-1) tris(hydroxymethyl) aminomethane, 40 mmol L(-1) phosphoric acid and 10% (v/v) ethanol, at pH 2.1. A fused-silica capillary of 32 cm (50 µm ID×375 µm OD) was used in the experiments and samples and standards were analyzed employing the short-end injection procedure (8.5 cm effective length). The instrumental analysis time of the optimized method was 1.53 min (approx. 39 runs per hour). The validation of the proposed method for the determination of betaine and methionine showed good linearity (R(2)>0.999), adequate limit of detection (LOD <8 mg L(-1)) for the concentration in the samples and inter-day precision values lower than 3.5% (peak area and time migration). The results for the quantification of the amino acids in the samples determined by the CZE-UV method developed were statistically equal to those obtained with the comparative LC-MS/MS method according to the paired t-test with a confidence level of 95%.

  5. Chiral gels derived from secondary ammonium salts of (1R,3S-(+-camphoric acid

    Directory of Open Access Journals (Sweden)

    Tapas Kumar Adalder

    2010-09-01

    Full Text Available In order to have access to chiral gels, a series of salts derived from (1R,3S-(+-camphoric acid and various secondary amines were prepared based on supramolecular synthon rationale. Out of seven salts prepared, two showed moderate gelation abilities. The gels were characterized by differential scanning calorimetry, table top rheology, scanning electron microscopy, single crystal and powder X-ray diffraction. Structure property correlation based on X-ray diffraction techniques remain inconclusive indicating that some of the integrated part associated with the gelation phenomena requires a better understanding.

  6. Efficacy of Neutral Electrolyzed Water, Quaternary Ammonium and Lactic Acid-Based Solutions in Controlling Microbial Contamination of Food Cutting Boards Using a Manual Spraying Technique.

    Science.gov (United States)

    Al-Qadiri, Hamzah M; Ovissipour, Mahmoudreza; Al-Alami, Nivin; Govindan, Byju N; Shiroodi, Setareh Ghorban; Rasco, Barbara

    2016-05-01

    Bactericidal activity of neutral electrolyzed water (NEW), quaternary ammonium (QUAT), and lactic acid-based solutions was investigated using a manual spraying technique against Salmonella Typhimurium, Escherichia coli O157:H7, Campylobacter jejuni, Listeria monocytogenes and Staphylococcus aureus that were inoculated onto the surface of scarred polypropylene and wooden food cutting boards. Antimicrobial activity was also examined when using cutting boards in preparation of raw chopped beef, chicken tenders or salmon fillets. Viable counts of survivors were determined as log10 CFU/100 cm(2) within 0 (untreated control), 1, 3, and 5 min of treatment at ambient temperature. Within the first minute of treatment, NEW and QUAT solutions caused more than 3 log10 bacterial reductions on polypropylene surfaces whereas less than 3 log10 reductions were achieved on wooden surfaces. After 5 min of treatment, more than 5 log10 reductions were achieved for all bacterial strains inoculated onto polypropylene surfaces. Using NEW and QUAT solutions within 5 min reduced Gram-negative bacteria by 4.58 to 4.85 log10 compared to more than 5 log10 reductions in Gram-positive bacteria inoculated onto wooden surfaces. Lactic acid treatment was significantly less effective (P < 0.05) compared to NEW and QUAT treatments. A decline in antimicrobial effectiveness was observed (0.5 to <2 log10 reductions were achieved within the first minute) when both cutting board types were used to prepare raw chopped beef, chicken tenders or salmon fillets. © 2016 Institute of Food Technologists®

  7. pH-controlled quaternary ammonium herbicides capture/release by carboxymethyl-β-cyclodextrin functionalized magnetic adsorbents: Mechanisms and application

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chang; Wang, Peng [Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing 100193 (China); Shen, Zhigang [Zhong Nong Fa Seed Industry Group Co. Ltd, Beijing 600313 (China); Liu, Xueke; Zhou, Zhiqiang [Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing 100193 (China); Liu, Donghui, E-mail: liudh@cau.edu.cn [Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing 100193 (China)

    2015-12-11

    In our work, the pH-controlled magnetic solid phase extraction for the determination of paraquat and diquat was introduced firstly. Furthermore, to clarify the mechanism of carboxymethyl-β-cyclodextrin functionalized magnetic adsorbents, we studied the pH-responsive supramolecular interaction between carboxymethyl-β-cyclodextrin (CM-β-CD) and paraquat/diquat by ultraviolet–visible (UV–vis) spectroscopy and nuclear magnetic resonance (NMR) experiment, and the energy-minimized structures were also obtained. Then, the functional group CM-β-CD was modified on the surface of magnetic materials to synthesize the adsorbent. The Fourier transform infrared spectrum (FT-IR) results proved the successful modification of CM-β-CD. Thus, this absorbent was applied for the determination of paraquat and diquat in water. Under the optimal condition, limits of detection (LODs) of paraquat and diquat were 0.8 μg L{sup −1} and 0.9 μg L{sup −1}, relative standard deviations (RSD) and recoveries varied 0.7–4.6% and 86.5–106.6%, respectively. Good recoveries (70.2–100.0%) and low RSD (1.7–9.6%) were achieved in analyzing spiked water samples. Furthermore, with the capillary electrophoresis (CE) as the analyser, the whole analytical process did not need the attendance of organic solvents. - Highlights: • The carboxymethyl-β-cyclodextrin functionalized magnetic adsorbents were synthesized. • The adsorbents could capture or release quaternary ammonium herbicides by changing pH. • The adsorbents were applied in the analysis of real water samples. • There is no attendance of organic solvents in the whole analysis process.

  8. Increased water resistance of paper treated with amylose-fatty ammonium salt inclusion complexes

    Science.gov (United States)

    Amylose inclusion complexes were prepared from high amylose corn starch and the HCl salts of hexadecylamine and octadecylamine. Solutions of the complexes were applied to paper at concentrations of 2-4%. After the treated papers were dried, sodium hydroxide solution was applied to convert the adsorb...

  9. Some effects of ammonium salts on renal histology and function in the dog.

    Science.gov (United States)

    Orvell, B D; Wesson, L G

    1976-01-01

    NH4Cl was infused into the left renal artery of anesthetized dogs at 50-125 mum/kg/min for up to 110 min. Renal blood flow declined early then increased to supra-control levels during infusion. Kidneys perfused at 125 mum/kg/min for 90 min showed patchy to confluent mixtures of cortical necrosis and tubular necrosis. Experimental kidneys invariably showed lower urine osmolality than contralateral controls 48 h after perfusion. Kidneys with necrosis showed depressed creatinine clearance as well. Renal artery infusion of NH4 acetate or intravenous infusion of NaHCO3 during arterial infusion of NH4Cl prevented significant acidosis and caused minimal histological changes, but depression of urine osmolality was not prevented. It is concluded that renal ammonium concentrations up to 40 mum/liter for 90 min does not cause tubular necrosis but does impair urine concentration. Severe tissue damage followed renal exposure to high ammonium concentrations in the presence of metabolic or renal acidosis.

  10. A universal fixation method based on quaternary ammonium salts (RNAlater) for omics-technologies: Saccharomyces cerevisiae as a case study

    DEFF Research Database (Denmark)

    Eijsden, Rudy G. E. van; Stassen, Catherine; Daenen, Luk

    2013-01-01

    Genomics, transcriptomics, proteomics and fluxomics are powerful omics-technologies that play a major role in today’s research. For each of these techniques good sample quality is crucial. Major factors contributing to the quality of a sample is the actual sampling procedure itself and the way th...

  11. Non-leaching antimicrobial surfaces through polydopamine bio-inspired coating of quaternary ammonium salts or an ultrashort antimicrobial lipopeptide.

    OpenAIRE

    Shalev, Tel; Gopin, Anna; Bauer, Michael; Stark, Robert W.; Rahimipour, Shai

    2012-01-01

    Bacterial fouling on surfaces significantly increases the resistance of bacteria toward antibiotics, which leads to medical complications and a corresponding financial burden. Here, we report on a general and robust technique for facile modification of various surfaces with different antibacterial agents. Our approach in this study was inspired by the strong adhesion of mussel adhesion proteins (MAPs) to many types of surfaces, including metals, polymers, and inorganic materials. Thus, glass ...

  12. Microwave synthesis of delaminated acid saponites using quaternary ammonium salt or polymer as template. Study of pH influence

    NARCIS (Netherlands)

    Gebretsadik, Fiseha B.; Mance, Deni; Baldus, Marc; Salagre, Pilar; Cesteros, Yolanda

    2015-01-01

    Mesoporous saponites were prepared at pH8 and 13 without and with template (surfactant or polymer) at 453K and autogenic pressure using microwaves or conventional oven during the hydrothermal ageing treatment. Acidity was obtained by calcination of the NH4-form. The effect of dilution (H<

  13. Microwave synthesis of delaminated acid saponites using quaternary ammonium salt or polymer as template. Study of pH influence

    NARCIS (Netherlands)

    Gebretsadik, Fiseha B.; Mance, Deni; Baldus, Marc; Salagre, Pilar; Cesteros, Yolanda

    2015-01-01

    Mesoporous saponites were prepared at pH8 and 13 without and with template (surfactant or polymer) at 453K and autogenic pressure using microwaves or conventional oven during the hydrothermal ageing treatment. Acidity was obtained by calcination of the NH4-form. The effect of dilution

  14. Decomposition of diverse solid inorganic matrices with molten ammonium bifluoride salt for constituent elemental analysis

    Energy Technology Data Exchange (ETDEWEB)

    O' Hara, Matthew J.; Kellogg, Cyndi M.; Parker, Cyrena M.; Morrison, Samuel S.; Corbey, Jordan F.; Grate, Jay W.

    2017-09-01

    Ammonium bifluoride (ABF, NH4F·HF) is a well-known reagent for converting metal oxides to fluorides and for its applications in breaking down minerals and ores in order to extract useful components. It has been more recently applied to the decomposition of inorganic matrices prior to elemental analysis. Herein, a sample decomposition method that employs molten ABF sample treatment in the initial step is systematically evaluated across a range of inorganic sample types: glass, quartz, zircon, soil, and pitchblende ore. Method performance is evaluated across the two variables: duration of molten ABF treatment and ABF reagent mass to sample mass ratio. The degree of solubilization of these sample classes are compared to the fluoride stoichiometry that is theoretically necessary to enact complete fluorination of the sample types. Finally, the sample decomposition method is performed on several soil and pitchblende ore standard reference materials, after which elemental constituent analysis is performed by ICP-OES and ICP-MS. Elemental recoveries are compared to the certified values; results indicate good to excellent recoveries across a range of alkaline earth, rare earth, transition metal, and actinide elements.

  15. Prenyl Ammonium Salts - New Carriers for Gene Delivery: A B16-F10 Mouse Melanoma Model.

    Directory of Open Access Journals (Sweden)

    Emilia Grecka

    Full Text Available Prenyl ammonium iodides (Amino-Prenols, APs, semi-synthetic polyprenol derivatives were studied as prospective novel gene transfer agents.AP-7, -8, -11 and -15 (aminoprenols composed of 7, 8, 11 or 15 isoprene units, respectively were examined for their capacity to form complexes with pDNA, for cytotoxicity and ability to transfect genes to cells.All the carriers were able to complex DNA. The highest, comparable to commercial reagents, transfection efficiency was observed for AP-15. Simultaneously, AP-15 exhibited the lowest negative impact on cell viability and proliferation-considerably lower than that of commercial agents. AP-15/DOPE complexes were also efficient to introduce pDNA to cells, without much effect on cell viability. Transfection with AP-15/DOPE complexes influenced the expression of a very few among 44 tested genes involved in cellular lipid metabolism. Furthermore, complexes containing AP-15 and therapeutic plasmid, encoding the TIMP metallopeptidase inhibitor 2 (TIMP2, introduced the TIMP2 gene with high efficiency to B16-F10 melanoma cells but not to B16-F10 melanoma tumors in C57BL/6 mice, as confirmed by TIMP2 protein level determination.Obtained results indicate that APs have a potential as non-viral vectors for cell transfection.

  16. X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry characterization of aging effects on the mineral fibers treated with aminopropylsilane and quaternary ammonium compounds

    DEFF Research Database (Denmark)

    Zafar, Ashar; Schjødt-Thomsen, Jan; Sodhi, R.

    2012-01-01

    X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry were used to investigate the aging effects on the aminopropylsilane (APS) and quaternary ammonium surfactant-treated mineral fibers. APS-coated mineral fiber samples were treated with cationic surfactant...... (PCA) was applied to the time-of-flight secondary ion mass spectrometry spectra, and an increase in the intensities of APS characteristic peaks were observed after aging. The observed increase in the signals of APS originates from underlying silanized fibers after the removal of the surfactant...

  17. 'Remote' adiabatic photoinduced deprotonation and aggregate formation of amphiphilic N-alkyl-N-methyl-3-(pyren-1-yl)propan-1-ammonium chloride salts.

    Science.gov (United States)

    Abraham, Shibu; Weiss, Richard G

    2011-11-30

    The absorption and emission properties of a series of amphiphilic N-alkyl-N-methyl-3-(pyren-1-yl)propan-1-ammonium chloride salts were investigated in solvents of different polarities and over a wide concentration range. For example, at 10(-5) M concentrations in tetrahydrofuran (THF), salts with at least one N-H bond exhibited broad, structureless emissions even though time-correlated single photon counting (TCSPC) experiments indicated negligible static or dynamic intermolecular interactions. Salts with a butylene spacer or lacking an N-H bond showed no discernible structureless emission; their emission spectra were dominated by the normal monomeric fluorescence of a pyrenyl group and the TCSPC histograms could be interpreted on the basis of intramolecular photophysics. The broad, structureless emission is attributed to an unprecedented, rapid, adiabatic proton-transfer to the medium, followed by the formation of an intramolecular exciplex consisting of amine and pyrenyl groups. The proposed mechanism involves excitation of a ground-state conformer of the salts in which the ammonium group sits over the pyrenyl ring due to electrostatic stabilization. At higher concentrations, with longer N-alkyl groups, or in selected solvents, electronic excitation of the salts led to dynamic and static excimeric emissions. For example, whereas the emission spectrum of 10(-3) M N-hexyl-N-methyl-3-(pyren-1-yl)propan-1-ammonium chloride in THF consisted of comparable amounts of monomeric and excimeric emission, the emission from 10(-5) M N-dodecyl-N-methyl-3-(pyren-1-yl)propan-1-ammonium chloride in 1:9 (v:v) ethanol/water solutions was dominated by excimeric emission, and discrete particles near micrometer size were discernible from confocal microscopy and dynamic light scattering experiments. Comparison of the static and dynamic emission characteristics of the particles and of the neat solid of N-dodecyl-N-methyl-3-(pyren-1-yl)propan-1-ammonium chloride indicate that molecular

  18. Evaluation of polyacrylamide gels with accelerator ammonium salts for water shutoff in ultralow temperature reservoirs: Gelation performance and application recommendations

    Directory of Open Access Journals (Sweden)

    Hu Jia

    2016-03-01

    Full Text Available Water shutoff in ultralow temperature reservoirs has received great attention in recent years. In previous study, we reported a phenol-formaldehyde-based gel formula with ammonium salt which can provide a gelation time between 2 hrs and 2 days at 25 °C. However, systematic evaluation and field recommendations of this gel formula when encountering complex reservoirs environment are not addressed. In this paper, how and why such practical considerations as water composition, temperature, pH, weight ratio of formaldehyde to resorcinol and contaminant Fe3+ to affect the gelation performance are examined. Brookfield DV-III and scanning electron microscopy (SEM are employed respectively for viscosity measurement and microstructure analysis. SEM results further illustrate the mechanism of the effect of salinity on gelation performance. It reveals that crosslinking done by covalent bond has great advantage for gel stability under high salinity environment. The target gel formula can provide desirable gelation time below 60 °C, perfect for 15–45 °C, while it is unfeasible to use high salinity to delay gelation at 60 °C. We summarized the effect of salinity on gelation performance of different gel formulas from the present study and published literature. The summarized data can provide important guideline for gel formula design before conducting any kinds of experiments. The variation of gelation performance at different salinity may be dominated by the interaction between crosslinker-salt-polymer, not only limited to “charge-screening effect” and “ion association” proposed by several authors. We hope the analysis encouraging further investigations. Some recommendations for field application of this gel are given in the end of this paper.

  19. Ammoxidation of 2-methyl pyrazine on supported ammonium salt of 12-molybdophosphoric acid catalysts: The influence of nature of support

    Indian Academy of Sciences (India)

    Katabathini Narasimharao; B Hari Babu; N Lingaiah; P S Sai Prasad; Shaeel A Al-Thabaiti

    2014-03-01

    Influence of the nature of support on the formation of catalytically active species was investigated to clarify the key factor for the synthesis of supported ammonium salt of 12-molybdophosphoric acid (AMPA) catalyst which maintains the activity of ammoxidation during 2-methylpyrazine reaction.With this aim, different loadings of niobia-, silica- and alumina-, supported AMPA catalysts were prepared. The AMPA loading was varied in the range of 5-25 wt%. The synthesized solids were characterized by nitrogen adsorption for BET surface area, XRD and 31P MAS NMR techniques. All the AMPA-supported samples are poorly crystalline even after 25 wt% AMPA loading. Investigations using 31P MAS NMR spectroscopy of samples revealed that Keggin ion existed as at least five different species on the supports. The investigated properties were acidity of the support and amount of AMPA loading on the support. Active sites for the ammoxidation of MP on supported AMPA catalysts seem to be the interacted and/or the lacunary species.Maximum catalytic activity could be obtained at lower loadings with AMPA deposited on acidic supports whereas the less acidic supports require higher loading. It was found that in order to efficiently generate the active interactive species, the support must have an acidity which promotes the formation of support-AMPA interactive species. It is possible to enhance the catalytic activity of the supported AMPA catalyst for ammoxidation of 2-methylpyrazine by controlling the acidity of the support and AMPA loading on the support.

  20. Two di-alkyl-ammonium salts of 2-amino-4-nitro-benzoic acid: crystal structures and Hirshfeld surface analysis.

    Science.gov (United States)

    Wardell, James L; Jotani, Mukesh M; Tiekink, Edward R T

    2016-12-01

    The crystal structures of two ammonium salts of 2-amino-4-nitro-benzoic acid are described, namely di-methyl-aza-nium 2-amino-4-nitro-benzoate, C2H8N(+)·C7H5N2O4(-), (I), and di-butyl-aza-nium 2-amino-4-nitro-benzoate, C8H20N(+)·C7H5N2O4(-), (II). The asymmetric unit of (I) comprises a single cation and a single anion. In the anion, small twists are noted for the carboxyl-ate and nitro groups from the ring to which they are connected, as indicated by the dihedral angles of 11.45 (13) and 3.71 (15)°, respectively; the dihedral angle between the substituents is 7.9 (2)°. The asymmetric unit of (II) comprises two independent pairs of cations and anions. In the cations, different conformations are noted in the side chains in that three chains have an all-trans [(+)-anti-periplanar] conformation, while one has a distinctive kink resulting in a (+)-synclinal conformation. The anions, again, exhibit twists with the dihedral angles between the carboxyl-ate and nitro groups and the ring being 12.73 (6) and 4.30 (10)°, respectively, for the first anion and 8.1 (4) and 12.6 (3)°, respectively, for the second. The difference between anions in (I) and (II) is that in the anions of (II), the terminal groups are conrotatory, forming dihedral angles of 17.02 (8) and 19.0 (5)°, respectively. In each independent anion of (I) and (II), an intra-molecular amino-N-H⋯O(carboxyl-ate) hydrogen bond is formed. In the crystal of (I), anions are linked into a jagged supra-molecular chain by charge-assisted amine-N-H⋯O(carboxyl-ate) hydrogen bonds and these are connected into layers via charge-assisted ammonium-N-H⋯O(carboxyl-ate) hydrogen bonds. The resulting layers stack along the a axis, being connected by nitro-N-O⋯π(arene) and methyl-C-H⋯O(nitro) inter-actions. In the crystal of (II), the anions are connected into four-ion aggregates by charge-assisted amino-N-H⋯O(carboxyl-ate) hydrogen bonding. The formation of ammonium

  1. Crystal structure of the heptamolybdate(VI) (paramolybdate) ion, [Mo7O24]6-, in the ammonium and potassium tetrahydrate salts

    Science.gov (United States)

    Evans, H.T.; Gatehouse, B.M.; Leverett, P.

    1975-01-01

    The crystal structures of the isomorphous salts MI6 [Mo7O24],4H2O (M = NH4 or K) have been refined by three-dimensional X-ray diffraction methods. Unit cell dimensions of these monoclinic compounds, space group P21/C with Z = 4, are, ammonium salt: a = 8.3934 ?? 0.0008, b = 36.1703 ?? 0.0045, c = 10.4715 ?? 0.0011 A??, ?? = 115.958?? ?? 0.008??; and potassium salt: a = 8.15 ?? 0.02, b = 35.68 ?? 0.1, c = 10.30 ?? 0.02 A??, ?? = 115.2?? ?? 02??. By use of multiple Weissenberg patterns, 8197 intensity data (Mo-K?? radiation) for the ammonium compound and 2178 (Cu-K?? radiation) for the potassium compound were estimated visually and used to test and refine Lindqvist's proposed structure in the space group P21/c. Lindqvist's structure was confirmed and the full matrix least-squares isotropic refinement led to R 0.076 (ammonium) 0.120 (potassium), with direct unambiguous location of the cations and water molecules in the potassium compound.

  2. 原料乳中铵盐掺假检测方法%Raw milk adulteration detection method of ammonium salt

    Institute of Scientific and Technical Information of China (English)

    贺俊英; 贺月恩; 王丹慧; 刘美霞; 李梅

    2012-01-01

    Research in raw milk adulteration ammonium salt material qualitative detection method, through to the raw milk which artificial add quantitative ammonium salt test reagent, found through experiments, and the results show that this method is mainly used in the detection of raw milk of ammonium salt mass fraction in more than 0.025% have good maneuverability, and at the same time, methods the operation is simple, the result for observation, suitable for breeding, acquisitions, dairy products enterprise of raw milk quality acceptance inspection.%通过向原料乳中人为添加定量铵盐测试试剂,研究原料乳中铵盐掺假物质定性检测的方法。实验结果表明,该方法用于检测原料乳中铵盐质量分数在0.025%以上,具有良好的可操作性,同时方法操作简单,结果便于观察,适用于在养殖、收购、乳制品企业等进行原料乳质量验收检验。

  3. 新型有机硅季(鏻)盐的合成及应用%Preparation and application of new silicone quaternary phosphonium salt

    Institute of Scientific and Technical Information of China (English)

    王萌; 闵洁

    2012-01-01

    以三苯基膦和氯丙基三乙氧基硅烷为原料,通过SN2反应合成了新型有机硅季(鏻)盐,并采用红外光谱及磷谱对其结构进行表征.将试验合成的有机硅季(鏻)盐用于纯棉织物抗菌整理,其用量为10%时,整理织物对大肠埃希菌和金黄葡萄球菌的抑菌率可达到87.1%、99.7%,且具有一定的抗菌耐洗性.扫描电镜和EDS分析表明,有机硅季(鏻)盐还可提高织物的热稳定性,且对织物的其它服用性能影响不大.%A new silicone quaternary phosphonium salt is synthesized by SN2 reaction using triphenylphosphine and γ-chloropro-pyl triethoxysilane as the raw materials. The product is characterized by FTIR and 31P spectra. The finished cotton fabric with 10% quaternary phosphonium salt has excellent and durable antibacterial property with inhibition of escherichia coli of 87.1% and staphylococcus aureus of 99.7%. SEM analysis and EDC analysis indicate that the silicone quaternary phosphonium salt can improve the thermal stability of treated cotton fabric and have little effect on the wearability.

  4. Influence of the Salting-out Effect of Ammonium Sulfate on the Gas-Particle Partitioning of Organic Compounds in the Atmosphere

    Science.gov (United States)

    Wang, C.; Lei, Y. D.; Endo, S.; Wania, F.

    2014-12-01

    As one of the major salts in the atmosphere, ammonium sulfate ((NH4)2SO4) influences significantly the partitioning of organic compounds into atmospheric aqueous phases. This salting out effect has important implications regarding the reactivity, transport and fate of organic compounds in atmospheric waters, particularly in aerosol particles because of the relatively large amount of salts present. However, very few studies have quantified the salting out effect of (NH4)2SO4. For the first time, we measured salting-out coefficients (or Setschenow constants) (KS [M-1]) for a large and diverse group of organic compounds in (NH4)2SO4 solutions at a wide range of salt concentrations, providing a reliable database for model development. KS values for (NH4)2SO4 are correlated with and always higher than KS for sodium chloride (NaCl), suggesting a higher salting-out effect of (NH4)2SO4. Three modeling approaches: a poly-parameter linear free energy relationship (pp-LFER), the quantum-chemical COSMOtherm software and the group contribution method AIMOFAC, were calibrated and evaluated in terms of their capability to predict KS. Relative merits of the prediction methods were identified. These models can be applied to estimate Setschenow constants for atmospherically relevant compounds involved in secondary organic aerosol formation based on chemical structure alone.

  5. Electrochemical synthesis of nanocrystalline In2O3:Sn (ITO) in an aqueous system with ammonium acetate as conducting salt.

    Science.gov (United States)

    Veith, M; Rabung, B; Grobelsek, I; Klook, M; Wagner, F E; Quilitz, M

    2009-04-01

    Nanoscaled so called indium tin oxide In2O3:Sn (ITO) with a specific BET surface area of 50 m2/g to 60 m2/g was prepared via an electrochemical method in an aqueous system containing ammonium acetate as conductive salt. As an intermediate product of the synthesis nanocrystalline In(OH)3 is obtained which serves as a precursor for the subsequent calcinations accompanied by tin doping resulting in ITO powders with various tin concentrations. Its phase transitions and the reduction behaviour of hydroxide to oxide during the calcination process in air flow and forming gas atmosphere of N2 to H2 ratio of 95 to 5 respectively, have been investigated by high temperature X-ray diffraction, TG/DSC/MS, HRTEM and SEM analysis. Depending on the atmosphere dehydration of tin doped In(OH)3 started at 150 degrees C, cubic ITO solid solution formed between 190 degrees C and 300 degrees C. The total weight loss of the hydroxide of approx. 21% occurred mainly below 360 degrees C and the burn-out of organic components mainly between 308 degrees C and 316 degrees C. The results of DSC and MS analyses were in good agreement with the results of the X-ray diffraction. In addition, the products have been characterized by EDX associated with TEM, XPS, ICP-AES, BET analysis and 119Sn Mössbauer spectroscopy. Completely reacted samples of ITO have been processed to pellets, calcined and sintered in the temperature range between 900 degrees C and 1100 degrees C and characterized by measurements of the electrical conductivities of bulk and surface in the reduced as well as in the oxidized state giving values up to 1400 Scm(-1).

  6. STUDY ON BACTERICIDAL EFFICACY OF A QUATERNARY AMMONIUM COMPOUNDS DISINFECTANT TO LEGIONELLA PNEUMOPHILA%一种复方季铵盐类消毒液杀灭嗜肺军团菌效果的研究

    Institute of Scientific and Technical Information of China (English)

    蔡怡珊; 刘海涛; 黄金宝; 张柳; 周艳

    2011-01-01

    Objective To study the bactericidal efficacy and influencing factors of a quaternary ammonium compounds disinfectant to Legionella pneumophila. Methods Suspension quantitative bactericidal test was performed to observe the germicidal efficacy to L. pneumophila of didecyldimethylammonium chloride compounds disinfectant and the influencing factors. Results The killing log value of L. pneumophila was above 5.0 when the quaternary ammonium compounds disinfectant containing 59.2 mg/L active ingredient contact with 5 minutes. The bactericidal efficacy was enhanced with increasing disinfectant concentration and prolonging contact time. The bactericidal efficacy was decreased with the down of pH. Conclusion The quaternary ammonium compounds disinfectant can kill L. pneumophila at low concentration, but acidic pH can decrease its germicidal efficacy.%目的 研究一种复方季铵盐消毒剂对嗜肺军团菌杀灭效果及其影响因素.方法 应用悬液定量杀菌试验方法,对以二癸基二甲基氯化铵为杀菌成分的复方季铵盐消毒液杀灭嗜肺军团菌的效果及其影响因素进行了观察.结果 以活性物含量为59.2 mg/L的该复方季铵盐消毒剂对悬液内嗜肺军团菌作用5 min,平均杀灭对数值>5.0.该复方季铵盐消毒剂随浓度增加和作用时间延长,其杀菌作用增强;但其随消毒液pH值降低,杀菌作用减弱.结论 该复方季铵盐消毒剂在较低浓度下对嗜肺军团杆菌杀灭效果较好,但消毒液pH值偏酸性会降低其杀菌效果.

  7. NUCHLEOPHILIC SUBSTITUTION REACTION OF CYANIDE AND METHOXYDE IONS TO QUATERNARY MANNICH BASE FROM VANILLIN

    Directory of Open Access Journals (Sweden)

    Bambang Purwono

    2010-06-01

    Full Text Available The nucleophilic substitution reaction to quaternary Mannich base from vanillin has been investigated. Mannich reaction to vanillin was carried out by refluxing mixture of vanillin, formaldehyde and dimethyl amine. Quaternary ammonium halide salt was obtained from reaction of Mannich vanillin base with methyl iodide in THF solvents and yielded  93.28%. Nucleophilic substituion to the halide salts with cyanide nucleophile produced 4-hidroxy-3-methoxy-5-(cyanomethylbenzaldehyde in 54.39% yield, with methoxyde ion obtained  4-hidroxy- 3-methoxy-5-(methoxy-methyl-benzaldehide in 67.80% yield. The nucleophilic substitution reaction showed that substituen of trimethylamino quaternary Mannich base can act as a good leaving on nucleophilic reaction substitutions.   Keywords: Mannich Reaction, Vanillin, nucleophilic substitution.

  8. NUCLEOPHILIC SUBSTITUTION REACTION OF CYANIDE AND METHOXYDE IONS TO QUATERNARY MANNICH BASE FROM VANILLIN

    Directory of Open Access Journals (Sweden)

    Bambang Purwono

    2010-06-01

    Full Text Available The nucleophilic substitution reaction to quaternary Mannich base from vanillin has been investigated. Mannich reaction to vanillin was carried out by refluxing mixture of vanillin, formaldehyde and dimethyl amine. Quaternary ammonium halide salt was obtained from reaction of Mannich vanillin base with methyl iodide in THF solvents and yielded 93.28 %. Nucleophilic substituion to the halide salts with cyanide nucleophile produced 4-hidroxy-3-methoxy-5-(cyanomethylbenzaldehyde in 54.39% yield. Reaction with methoxyde ion yielded 4-hydroxy- 3-methoxy-5-(methoxy -methylbenzaldehyde in 67.80% yield. The nucleophilic substitution reaction showed that trimethylamino substituent of quaternary Mannich base can act as a good leaving group on nucleophilic substitution reactions. Keywords: Mannich reaction, vanillin, nucleophilic substitution

  9. Salting-out extraction of allicin from garlic (Allium sativum L.) based on ethanol/ammonium sulfate in laboratory and pilot scale.

    Science.gov (United States)

    Li, Fenfang; Li, Qiao; Wu, Shuanggen; Tan, Zhijian

    2017-02-15

    Salting-out extraction (SOE) based on lower molecular organic solvent and inorganic salt was considered as a good substitute for conventional polymers aqueous two-phase extraction (ATPE) used for the extraction of some bioactive compounds from natural plants resources. In this study, the ethanol/ammonium sulfate was screened as the optimal SOE system for the extraction and preliminary purification of allicin from garlic. Response surface methodology (RSM) was developed to optimize the major conditions. The maximum extraction efficiency of 94.17% was obtained at the optimized conditions for routine use: 23% (w/w) ethanol concentration and 24% (w/w) salt concentration, 31g/L loaded sample at 25°C with pH being not adjusted. The extraction efficiency had no obvious decrease after amplification of the extraction. This ethanol/ammonium sulfate SOE is much simpler, cheaper, and effective, which has the potentiality of scale-up production for the extraction and purification of other compounds from plant resources.

  10. X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry characterization of aging effects on the mineral fibers treated with aminopropylsilane and quaternary ammonium compounds

    DEFF Research Database (Denmark)

    Zafar, Ashar; Schjødt-Thomsen, Jan; Sodhi, R.

    2012-01-01

    -resolution spectra is also observed. These results indicate that the concentration of hydrocarbon groups decreases after aging due to the partial removal of the long hydrocarbon chains of the surfactant and mineral oil and/or hydrolysis and segregation of APS to the fiber surface. The principal component analysis......X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry were used to investigate the aging effects on the aminopropylsilane (APS) and quaternary ammonium surfactant-treated mineral fibers. APS-coated mineral fiber samples were treated with cationic surfactant...... and mineral oil and aged at 70 °C temperature and 95% humidity. From quantitative XPS measurements, an increase in the atomic composition of oxygen, nitrogen, and silicon is observed after aging. An increase in the protonated amino groups in the N1s high-resolution spectra and C–N group in the C1s high...

  11. The effect of number and position of P=O/P=S bridging units on cavitand selectivity toward methyl ammonium salts.

    Science.gov (United States)

    Menozzi, Daniela; Pinalli, Roberta; Massera, Chiara; Maffei, Francesca; Dalcanale, Enrico

    2015-03-10

    The present work reports the synthesis and complexation properties of five mixed bridge P=O/P=S cavitands toward N,N-methyl butyl ammonium chloride (1) as prototype guest. The influence of number and position of P=O and P=S groups on the affinity of phosphonate cavitands toward 1 is assessed via ITC titrations in DCE as solvent. Comparison of the resulting Kass values, the enthalpic and entropic contributions to the overall binding with those of the parent tetraphosphonate Tiiii and tetrathiophosphonate TSiiii cavitands allows one to single out the simultaneous dual H-bond between the cavitand and the salt as the major player in complexation.

  12. Two-dimensional hydrogen-bonded polymers in the crystal structures of the ammonium salts of phenoxyacetic acid, (4-fluorophenoxyacetic acid and (4-chloro-2-methylphenoxyacetic acid

    Directory of Open Access Journals (Sweden)

    Graham Smith

    2014-12-01

    Full Text Available The structures of the ammonium salts of phenoxyacetic acid, NH4+·C8H6O3−, (I, (4-fluorophenoxyacetic acid, NH4+·C8H5FO3−, (II, and the herbicidally active (4-chloro-2-methylphenoxyacetic acid (MCPA, NH4+·C9H8ClO3−·0.5H2O, (III have been determined. All have two-dimensional layered structures based on inter-species ammonium N—H...O hydrogen-bonding associations, which give core substructures consisting primarily of conjoined cyclic motifs. The crystals of (I and (II are isomorphous with the core comprising R12(5, R12(4 and centrosymmetric R42(8 ring motifs, giving two-dimensional layers lying parallel to (100. In (III, the water molecule of solvation lies on a crystallographic twofold rotation axis and bridges two carboxyl O atoms in an R44(12 hydrogen-bonded motif, creating two R43(10 rings, which together with a conjoined centrosymmetric R42(8 ring incorporating both ammonium cations, generate two-dimensional layers lying parallel to (100. No π–π ring associations are present in any of the structures.

  13. Secondary Organic Aerosol and Brown Carbon Formation in the Sunlit Aqueous Phase: Aldehyde Photooxidation in the Presence of Ammonium Salts and Amines

    Science.gov (United States)

    De Haan, D. O.; Galloway, M. M.; Sharp, K. D.; Jiménez, N. G.

    2014-12-01

    The chemistry of water-soluble carbonyl compounds in clouds is now acknowledged as an important source of secondary organic aerosol. These reactive carbonyl compounds are oxidized to carboxylic acids and form oligomers by radical-radical reactions and by "dark reactions" with ammonium salts (AS) and/or amines. The latter class of reactions also produces light-absorbing brown carbon compounds, especially reactions involving methylglyoxal or glyoxal and amines. However, recent work has found that UV light fades the color of glyoxal + AS and methylgyloxal + AS reaction mixtures. We recently studied aldehyde-AS-amine reactions in sunlight and in control vessels at the same temperature to determine the effects of solar radiation on the aqueous-phase production of brown carbon. In sunlight, methylglyoxal reaction mixtures lost their initial color and failed to brown, indicating the photolytic loss of reactants and/or pre-brown intermediates. In many other reactions, brown products are lost to photolysis, reducing the overall browning of solutions exposed to sunlight. In other experiments, hydrogen peroxide was added to generate OH radicals by photolysis. In the presence of OH radicals, some carbonyl compound mixtures (e.g. those containing hydroxyacetone or glycolaldehyde) browned more rapidly when exposed to sunlight. This indicates the existence of uncharacterized photooxidative browning pathways involving aqueous-phase OH radicals, carbonyls, ammonium salts, and/or amine compounds.

  14. Experiment on Development of 30% Glyphosate Ammonium Salt Water Aqua%30%草甘膦铵盐水剂研制试验

    Institute of Scientific and Technical Information of China (English)

    余洋

    2012-01-01

    30%草甘膦铵盐水剂研制试验结果表明,低含量草甘膦母液通过除甲醛、浓缩制得30%草甘膦铵盐水剂,经测定,研制的样品质量稳定,甲醛含量〈10 g/kg,热贮(54℃±2℃)14 d分解率〈5%,符合国家规定的30%草甘膦铵盐水剂标准。%The experiment on development of 30% glyphosate ammonium salt water aqua results showed that by removing the low content of glyphosate mother liquor of formaldehyde and concentration, 30% ammonium salt glyphosate water aqua was acquired. Storage stability tests showed that the decomposition rate of the active ingredient was less than 5% at (54±2)℃ for 14 days and formaldehyde content was less than 10 g/kg.The physical and chemical properties of the formulated product confirmed to the requirements of EW formulation.

  15. Headgroup effects on the Krafft temperatures and self-assembly of ω-hydroxy and ω-carboxy hexadecyl quaternary ammonium bromide bolaform amphiphiles: micelles versus molecular clusters?

    Science.gov (United States)

    Holder, Simon J; Sriskantha, Bruntha C; Bagshaw, Stephen A; Bruce, Ian J

    2012-02-01

    Eight bolaform amphiphiles were synthesised and characterised; 4 α,ω-hydroxy-alkane trialkyl (and pyridyl) ammonium bromides and 4 α,ω-carboxy-alkane trialkyl (and pyridyl) ammonium bromides where the alkyl groups were methyl, ethyl and propyl. Four of these represented new compounds. Overall the Krafft temperatures (T(K)) of the eight amphiphiles were high, with 6 of the eight possessing T(K)s greater than 45 °C. Thus most of the amphiphiles could only expect to find applications at raised temperatures limiting their potential utility. However in addition to the previously reported α,ω-hydroxy-hexadecyl triethylammonium bromide (2b) with a T(K) of 19.1 °C, another amphiphile, α,ω-carboxy-hexadecyl tripropylammonium bromide (2c) has been identified with a T(K) near ambient temperatures (T(K) of 22.1 °C). This provides an acid functional ammonium bolaform amphiphile that micellises at ambient temperatures to complement the hydroxyl derivative. A correlation between T(K) and the product of the enthalpies and T(m)s of the compounds was observed for 7 of the eight compounds. No correlation between the amphiphile critical micelle concentrations (cmc) and T(K)s was observed confirming previous reports that T(K) values are predominantly determined by crystalline stability rather than solubility. Considerable differences were observed between the various amphiphile T(K)s at different pHs but no clear trend was apparent for the various compounds (despite the degree to which the compounds' carboxylic acid and hydroxyl functionalities were likely to be ionised). The cmcs for the amphiphiles were an order of magnitude larger than those for analogous mono-ammonium amphiphiles with little difference in between the hydroxyl- and carboxy-functionalised compounds. The aggregation numbers (N(agg)) obtained for all compounds were very low (N(agg)bolaforms were in the range 1.0-1.4 nm whereas those for the carboxy-compounds were in the range 2.1-2.4 nm. These results

  16. Synthesis and Anticoagulant Activity of Quaternary Ammonium Cationic Starch Sulfates%阳离子淀粉硫酸酯的制备及其抗凝血活性

    Institute of Scientific and Technical Information of China (English)

    樊李红; 沈元; 徐咏梅; 江澜; 王晓东; 周月; 潘晓然

    2011-01-01

    Quaternary ammonium cationic starch sulfate(QACSS) was synthesized by chemical modification of quaternary ammonium cationic starch(QACS) with trisulfonated sodium amine(N(SO_3Na)_3).This sulfating agent was close to neutral,and synthesized by reaction of sodium bisulfite and sodium nitrite in aqueous solution.The reaction conditions for the sulfonation process were optimized through posttest-only control group design.The optimal pH value of the sulfating agent solution was 10.0,the optimal ratio of sulfating agent to QACS was 2.0/314.5(mol/g),the reaction temperature was 40 ℃,the reaction time was about 22 h,respectively.The DS of QACSS was measured by barium sulfate nephelometry method,and the biggest DS was 1.83.The molecular weight was determined as 2.51×104 by static light scattering.Anticoagulant activity of QACSS was investigated by APTT,TT and PT assays.The results showed that QACSS exhibited good anticoagulant activity.The results also showed that with the increase of DS and concentration,APTT increased significantly,but TT and PT do not increased obviously.APTT prolonged as the molecular weight rose firstly and then decreased slowly with further increase in molecular weight.The best molecular weight was around 2.51×104.In addition,the anticoagulant activity of QACSS was better than QACS.%采用由亚硫酸氢钠和亚硝酸钠在水溶液中合成的近似中性的酯化剂N(SO3Na)3在水溶液中对季铵型阳离子淀粉(QACS)进行改性处理,制备了季铵型阳离子淀粉硫酸酯(QACSS).通过单因素实验优化得到酯化反应的最佳反应条件:pH=10.0,酯化剂的摩尔量与QACS的质量之比2∶314.5(mol/g),反应温度40℃,反应时间为22 h.通过测定凝血酶原时间(PT)、凝血活酶时间(APTT)以及凝血酶时间(TT),证明了QACSS有较优的抗凝血活性.随着QACSS取代度和浓度的增加,APTT明显增长,而TT与

  17. The Effect of Number and Position of P=O/P=S Bridging Units on Cavitand Selectivity toward Methyl Ammonium Salts

    Directory of Open Access Journals (Sweden)

    Daniela Menozzi

    2015-03-01

    Full Text Available The present work reports the synthesis and complexation properties of five mixed bridge P=O/P=S cavitands toward N,N-methyl butyl ammonium chloride (1 as prototype guest. The influence of number and position of P=O and P=S groups on the affinity of phosphonate cavitands toward 1 is assessed via ITC titrations in DCE as solvent. Comparison of the resulting Kass values, the enthalpic and entropic contributions to the overall binding with those of the parent tetraphosphonate Tiiii and tetrathiophosphonate TSiiii cavitands allows one to single out the simultaneous dual H-bond between the cavitand and the salt as the major player in complexation.

  18. A Simple Halide-to-Anion Exchange Method for Heteroaromatic Salts and Ionic Liquids

    Directory of Open Access Journals (Sweden)

    Neus Mesquida

    2012-04-01

    Full Text Available A broad and simple method permitted halide ions in quaternary heteroaromatic and ammonium salts to be exchanged for a variety of anions using an anion exchange resin (A− form in non-aqueous media. The anion loading of the AER (OH− form was examined using two different anion sources, acids or ammonium salts, and changing the polarity of the solvents. The AER (A− form method in organic solvents was then applied to several quaternary heteroaromatic salts and ILs, and the anion exchange proceeded in excellent to quantitative yields, concomitantly removing halide impurities. Relying on the hydrophobicity of the targeted ion pair for the counteranion swap, organic solvents with variable polarity were used, such as CH3OH, CH3CN and the dipolar nonhydroxylic solvent mixture CH3CN:CH2Cl2 (3:7 and the anion exchange was equally successful with both lipophilic cations and anions.

  19. Selective sampling and measurement of Cr (VI) in water with polyquaternary ammonium salt as a binding agent in diffusive gradients in thin-films technique

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Hong, E-mail: redastar@163.com [College of Chemistry, Chemical Engineering and Food Safety, Bohai University (China); Research Institute of Food Science, Bohai University (China); Food Safety Key Lab of Liaoning Province, Jinzhou 121013 (China); Zhang, Yang-Yang; Zhong, Ke-Li; Guo, Lian-Wen [College of Chemistry, Chemical Engineering and Food Safety, Bohai University (China); Research Institute of Food Science, Bohai University (China); Food Safety Key Lab of Liaoning Province, Jinzhou 121013 (China); Gu, Jia-Li [College of Chemistry, Chemical Engineering and Food Safety, Bohai University (China); Bo, Le; Zhang, Meng-Han [College of Chemistry, Chemical Engineering and Food Safety, Bohai University (China); Research Institute of Food Science, Bohai University (China); Food Safety Key Lab of Liaoning Province, Jinzhou 121013 (China); Li, Jian-Rong, E-mail: lijianrong@zjgsu.edu.cn [College of Chemistry, Chemical Engineering and Food Safety, Bohai University (China); Research Institute of Food Science, Bohai University (China); Food Safety Key Lab of Liaoning Province, Jinzhou 121013 (China)

    2014-04-01

    Graphical abstract: - Highlights: • We develop a new DGT device for in situ sampling Cr (VI) in water. • Polyquaternary ammonium salt (PQAS) was used as binding agent of DGT device. • Cr (VI) can be accumulated in the PQAS binding phase whereas Cr (III) cannot. • The DGT performance was independent of pH 3–12 and ionic strength 1 × 10{sup −3}–1 mol L{sup −1}. - Abstract: A diffusive gradients in thin films (DGT) device with polyquaternary ammonium salt (PQAS) as a novel binding agent (PQAS DGT) combined with graphite furnace atomic absorption spectrometry (GFAAS) was developed for the selective sampling and measurement of Cr (VI) in water. The performance of PQAS DGT was independent of pH 3–12 and ionic strength from 1 × 10{sup −3} to 1 mol L{sup −1}. DGT validation experiments showed that Cr (VI) was measured accurately as well as selectively by PQAS DGT, whereas Cr (III) was not determined quantitatively. Compared with diphenylcarbazide spectrophotometric method (DPC), the measurement of Cr (VI) with PQAS DGT was agreement with that of DPC method in the industrial wastewater. PQAS-DGT device had been successfully deployed in local freshwater. The concentrations of Cr (VI) determined by PQAS DGT coupled with GFAAS in Nuer River, Ling River and North Lake were 0.73 ± 0.09 μg L{sup −1}, 0.50 ± 0.07 μg L{sup −1} and 0.61 ± 0.07 μg L{sup −1}, respectively. The results indicate that PQAS DGT device can be used for the selective sampling and measurement Cr (VI) in water and its detection limit is lower than that of DPC method.

  20. Characterisation of quaternary polymethacrylate films containing tartaric acid, metoprolol free base or metoprolol tartrate.

    Science.gov (United States)

    Glaessl, B; Siepmann, F; Tucker, I; Siepmann, J; Rades, T

    2009-11-01

    The aim of this study was to better understand the interactions between metoprolol tartrate and quaternary polymethacrylate (Eudragit RL and Eudragit RS) films. For reasons of comparison, polymeric films containing the free base metoprolol or free tartaric acid were also prepared. Systems containing various amounts of the free base, free acid and the salt were characterised using polarising light microscopy, X-ray powder diffraction, differential scanning calorimetry and mechanical analysis (puncture test). The free base is the most efficient plasticiser of the three species for Eudragit RL and Eudragit RS, but with limited solubility in the polymers. Due to its hydrophobicity, it can interact with the hydrophobic polymer backbones. In contrast, in salt containing films, ionic interactions between the positively charged quaternary ammonium groups and the negatively charged tartrate anions apparently occur, this being suggested by the different effects on Eudragit RL versus RS, which have different contents of quaternary ammonium groups. Importantly, the combination of acid and base as a salt avoids drug precipitation at higher metoprolol contents. The obtained new insight into the occurring drug-polymer interactions can help to facilitate the development/optimisation of this type of dosage forms.

  1. Synthesis of Novel Well-degraded Quaternary Ammonium Gemini Surfactant%新型易降解的季铵盐型Gemini表面活性剂的合成

    Institute of Scientific and Technical Information of China (English)

    姜小明; 赵濉; 宫清涛

    2012-01-01

    N,N-二甲基丙二胺与脂肪酸(癸酸、月桂酸或肉豆蔻酸)反应制得长链酰胺(3a ~ 3c);3与1,4-二溴丁烷反应合成了新型易降解的季铵盐型Gemini表面活性剂(1a ~1c),其结构经1H NMR和IR表征.测试结果表明,1具有极低的临界胶团浓度、较强的乳化和增溶能力.%The novel well-degraded quaternary ammonium Gemini surfactants (la ~ lc) with amide were synthesized by the reaction of 1,4-dibromobutane with W-long chain amides which were prepared by the reaction of N,N-dimethyl propyl diamine with aliphatic acid(decylie acid, lauric acid or tetra decanoic acid). The structures were characterized by 1H NMR and IR. The result showed that 1 ex hibited low critical micelle concentration and high emulsification function.

  2. Prospective cluster controlled crossover trial to compare the impact of an improved hydrogen peroxide disinfectant and a quaternary ammonium-based disinfectant on surface contamination and health care outcomes.

    Science.gov (United States)

    Boyce, John M; Guercia, Kerri A; Sullivan, Linda; Havill, Nancy L; Fekieta, Renee; Kozakiewicz, Janet; Goffman, David

    2017-09-01

    Quaternary ammonium-based (Quat) disinfectants are widely used, but they have disadvantages. This was a 12-month prospective cluster controlled crossover trial. On 4 wards, housekeepers performed daily cleaning using a disinfectant containing either 0.5% improved hydrogen peroxide (IHP) or Quat. Each month, 5-8 high-touch surfaces in several patient rooms on each ward were tagged with a fluorescent marker and cultured before and after cleaning. Hand hygiene compliance rates and antimicrobial usage on study wards were obtained from hospital records. Outcomes included aerobic colony counts (ACCs), percent of wiped surfaces yielding no growth after cleaning, and a composite outcome of incidence densities of nosocomial acquisition and infection caused by vancomycin-resistant enterococci, methicillin-resistant Staphylococcus aureus, and Clostridium difficile infection. Statistical analysis was performed using χ(2) test, Fisher exact test, Welch test, and logistic regression methods. Mean ACCs per surface after cleaning were significantly lower with IHP (14.0) than with Quat (22.2) (P = .003). The proportion of surfaces yielding no growth after cleaning was significantly greater with IHP (240/500; 48%) than with Quat (182/517; 35.2%) (P Compared with a Quat disinfectant, the IHP disinfectant significantly reduced surface contamination and reduced a composite colonization or infection outcome. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  3. 四氟硼酸螺环季铵盐生产最佳参数的确定%Determination of Optimal Parameters in Spiro Quaternary Ammonium Tetrafluoroborate Production

    Institute of Scientific and Technical Information of China (English)

    张成立

    2012-01-01

    在50 L反应釜内,利用四氢吡咯、1,4-二溴丁烷与四氟硼酸离子交换合成了超级电容器电解质四氟硼酸螺环季铵盐,进行了电化学表征,讨论了配比、温度、反应时间等参数对产率的影响,总结出反应的最佳条件,并对反应釜的放大效应进行了初步探讨。%Supercapacitor electrolyte,spiro quaternary ammonium tetrafluoroborate was prepared by ion exchange of pyrrolidine,1,4-dibromobutane and fluoboric acid in 50 L reactor.In order to obtain the reaction optimal parameters,electrochemical characterization was conducted to the products,and the reaction ratio,reaction temperature and reaction time as well as other parameters were discussed.And also the magnification effect of reactor was preliminarily estimated.

  4. 21 CFR 184.1138 - Ammonium chloride.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium chloride. 184.1138 Section 184.1138 Food... Specific Substances Affirmed as GRAS § 184.1138 Ammonium chloride. (a) Ammonium chloride (NH4Cl, CAS Reg. No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution....

  5. Research on Synthesis of Chiral Quinine Quaternary Ammonium Ligand and Its Catalyzing Activity for Darzens Reaction%手性奎宁季铵盐配体的制备及在Darzens 反应中的催化作用研究

    Institute of Scientific and Technical Information of China (English)

    何健兴; 苏晶; 林汉森; 李建组

    2013-01-01

      文章以奎宁碱为母体,利用一系列卤代烃与奎宁碱发生季铵化反应,生成一系列手性奎宁季铵盐配体,所合成的配体结构均经1H-NMR、IR、MS 确证。并考察了该系列催化剂在不对称相转移催化2-氯代苯乙酮和苯甲醛的 Darzens 缩合反应中的催化性能,发现其手性催化性能跟取代基的立体位阻及电负性大小有关,其中由2-氟-4-溴苄基与奎宁形成的手性季铵盐不对称催化效果最好,所得缩合产物的 ee 值最高为46%。%Through using a series of halogenated hydrocarbons and quinine alkaline quaternization reaction, a series of chiral quinine quaternary ammonium salt ligand were generated with quinine as base matrix and its synthesized ligand structure were confirmed by 1H-NMR, IR, MS. And catalytic performance of ligands in Darzens condensation reaction between 2- chloroacetophenone and benzaldehyde in the asymmetric catalytic condition was investigated, implying that the chiral catalytic properties were associated with the steric size of substituents. And the best enantioselectivity for 46 %was obtained.

  6. Synthesis and Antibacterial Study of Sulfobetaine/Quaternary Ammonium-Modified Star-Shaped Poly[2-(dimethylamino)ethyl methacrylate]-Based Copolymers with an Inorganic Core.

    Science.gov (United States)

    Pu, Yuji; Hou, Zheng; Khin, Mya Mya; Zamudio-Vázquez, Rubi; Poon, Kar Lai; Duan, Hongwei; Chan-Park, Mary B

    2017-01-09

    Cationic polymethacrylates are interesting candidates for bacterial disinfectants since they can be made in large-scale by various well-established polymerization techniques such as atom transfer radical polymerization (ATRP). However, they are usually toxic or ineffective in serum and various strategies to improve their biocompatibility or nonfouling property have often resulted in compromised bactericidal activity. Also, star-shaped polymers are less explored than linear polymers for application as antibacterial compounds. In this paper, star polymers with poly[2-(dimethylamino)ethyl methacrylate] (PDMA) as the arms and polyhedral oligomeric silsesquioxane (POSS) as the core (POSS-g-PDMA) were successfully synthesized by ATRP. The minimum inhibition concentrations (MICs) of the synthesized POSS-g-PDMA are in the range of 10-20 μg/mL. POSS-g-PDMA was further modified by various hydrophilization strategies in attempting to reduce hemolysis. With quaternization of POSS-g-PDMA, the antibacterial activities of the obtained quaternary polymers are almost unchanged and the copolymers become relatively nonhemolytic. We also copolymerized sulfobetaine (SB) with POSS-g-PDMA to obtain random and block PDMA-co-PSB arm structures, where the PDMA and poly(sulfobetaine) were the cationic and zwitterionic blocks, respectively. The random cationic-zwitterionic POSS-g-(PDMA-r-PSB) copolymers showed poor antibacterial activity, while the block POSS-g-(PDMA-b-PSB) copolymers retained the antibacterial and hemolytic activity of the pristine POSS-g-PDMA. Further, the block copolymers of POSS-g-(PDMA-b-PSB) showed enhanced antifouling property and serum stability as seen by their nanoparticle size stability in the presence of serum and reduced red blood cell aggregation; the POSS-g-(PDMA-b-PSB) also somewhat retained its MIC in blood unlike the quaternized or random zwitterionic copolymers. The antibacterial kinetics study showed that Escherichia coli can be killed within 30 min by

  7. Seasonally resolved ice core records from West Antarctica indicate a sea ice source of sea-salt aerosol and a biomass burning source of ammonium

    Science.gov (United States)

    Pasteris, Daniel R.; McConnell, Joseph R.; Das, Sarah B.; Criscitiello, Alison S.; Evans, Matthew J.; Maselli, Olivia J.; Sigl, Michael; Layman, Lawrence

    2014-07-01

    The sources and transport pathways of aerosol species in Antarctica remain uncertain, partly due to limited seasonally resolved data from the harsh environment. Here, we examine the seasonal cycles of major ions in three high-accumulation West Antarctic ice cores for new information regarding the origin of aerosol species. A new method for continuous acidity measurement in ice cores is exploited to provide a comprehensive, charge-balance approach to assessing the major non-sea-salt (nss) species. The average nss-anion composition is 41% sulfate (SO42-), 36% nitrate (NO3-), 15% excess-chloride (ExCl-), and 8% methanesulfonic acid (MSA). Approximately 2% of the acid-anion content is neutralized by ammonium (NH4+), and the remainder is balanced by the acidity (Acy ≈ H+ - HCO3-). The annual cycle of NO3- shows a primary peak in summer and a secondary peak in late winter/spring that are consistent with previous air and snow studies in Antarctica. The origin of these peaks remains uncertain, however, and is an area of active research. A high correlation between NH4+ and black carbon (BC) suggests that a major source of NH4+ is midlatitude biomass burning rather than marine biomass decay, as previously assumed. The annual peak in excess chloride (ExCl-) coincides with the late-winter maximum in sea ice extent. Wintertime ExCl- is correlated with offshore sea ice concentrations and inversely correlated with temperature from nearby Byrd station. These observations suggest that the winter peak in ExCl- is an expression of fractionated sea-salt aerosol and that sea ice is therefore a major source of sea-salt aerosol in the region.

  8. Prenyl Ammonium Salts – New Carriers for Gene Delivery: A B16-F10 Mouse Melanoma Model

    Science.gov (United States)

    Grecka, Emilia; Statkiewicz, Malgorzata; Gorska, Agnieszka; Biernacka, Marzena; Grygorowicz, Monika Anna; Masnyk, Marek; Chmielewski, Marek; Gawarecka, Katarzyna; Chojnacki, Tadeusz; Swiezewska, Ewa; Malecki, Maciej

    2016-01-01

    Purpose Prenyl ammonium iodides (Amino-Prenols, APs), semi-synthetic polyprenol derivatives were studied as prospective novel gene transfer agents. Methods AP-7, -8, -11 and -15 (aminoprenols composed of 7, 8, 11 or 15 isoprene units, respectively) were examined for their capacity to form complexes with pDNA, for cytotoxicity and ability to transfect genes to cells. Results All the carriers were able to complex DNA. The highest, comparable to commercial reagents, transfection efficiency was observed for AP-15. Simultaneously, AP-15 exhibited the lowest negative impact on cell viability and proliferation—considerably lower than that of commercial agents. AP-15/DOPE complexes were also efficient to introduce pDNA to cells, without much effect on cell viability. Transfection with AP-15/DOPE complexes influenced the expression of a very few among 44 tested genes involved in cellular lipid metabolism. Furthermore, complexes containing AP-15 and therapeutic plasmid, encoding the TIMP metallopeptidase inhibitor 2 (TIMP2), introduced the TIMP2 gene with high efficiency to B16-F10 melanoma cells but not to B16-F10 melanoma tumors in C57BL/6 mice, as confirmed by TIMP2 protein level determination. Conclusion Obtained results indicate that APs have a potential as non-viral vectors for cell transfection. PMID:27088717

  9. Prenyl Ammonium Salts--New Carriers for Gene Delivery: A B16-F10 Mouse Melanoma Model.

    Science.gov (United States)

    Grecka, Emilia; Statkiewicz, Malgorzata; Gorska, Agnieszka; Biernacka, Marzena; Grygorowicz, Monika Anna; Masnyk, Marek; Chmielewski, Marek; Gawarecka, Katarzyna; Chojnacki, Tadeusz; Swiezewska, Ewa; Malecki, Maciej

    2016-01-01

    Prenyl ammonium iodides (Amino-Prenols, APs), semi-synthetic polyprenol derivatives were studied as prospective novel gene transfer agents. AP-7, -8, -11 and -15 (aminoprenols composed of 7, 8, 11 or 15 isoprene units, respectively) were examined for their capacity to form complexes with pDNA, for cytotoxicity and ability to transfect genes to cells. All the carriers were able to complex DNA. The highest, comparable to commercial reagents, transfection efficiency was observed for AP-15. Simultaneously, AP-15 exhibited the lowest negative impact on cell viability and proliferation--considerably lower than that of commercial agents. AP-15/DOPE complexes were also efficient to introduce pDNA to cells, without much effect on cell viability. Transfection with AP-15/DOPE complexes influenced the expression of a very few among 44 tested genes involved in cellular lipid metabolism. Furthermore, complexes containing AP-15 and therapeutic plasmid, encoding the TIMP metallopeptidase inhibitor 2 (TIMP2), introduced the TIMP2 gene with high efficiency to B16-F10 melanoma cells but not to B16-F10 melanoma tumors in C57BL/6 mice, as confirmed by TIMP2 protein level determination. Obtained results indicate that APs have a potential as non-viral vectors for cell transfection.

  10. Monosilane obtained from disproportionation of trimethoxysilane catalyzed with quaternary ammonium hydroxide resin%季铵碱树脂催化三甲氧基硅烷制备甲硅烷

    Institute of Scientific and Technical Information of China (English)

    杨恺; 安茂忠; 杨春晖; 张磊; 胡成发; 葛士彬

    2012-01-01

    High purity monosilane was prepared from disproportionation of trimethoxysilane catalyzed with quaternary ammonium hydroxide resin.Crude monosilane was analyzed by pulse discharge helium ionization detector.By-product tetramethoxysilane rectified was analyzed with gas chromatography-mass spectrometry and inductively coupled plasma-mass spectrometry.Experimental results show that the reaction conditions is the temperature range of 30~50 ℃ and the pressure range of 0.2~0.3 MPa.Contents of H2,O2,Ar,N2,and CH4 of crude monosilane were 221.12,1.76,1.61,17.97 and 0.15 μg/L,respectively.Content of tetramethoxysilane was 99.9wt%,and total metal impurities of tetramethoxysilane was less than 0.15 μg/L.Furthermore,the tetramethoxysiane can be material of high purity silica sol.The disproportionation reaction of trimethoxysilane catalyzed with quaternary ammonium hydroxide resin was happen at mild reaction conditions,and conversation of trimethoxysilane was 96wt%,and yield of monosilane was 95wt%.Catalyst is easy to buy,and fixed bed reactor is easy to control the reaction,and easy to continuous feeding,and then the technology has industrial production value.%为制备高纯度甲硅烷气体,用强碱性季铵碱阴离子交换树脂催化三甲氧基硅烷溶液进行歧化反应.采用脉冲放电氦离子化检测器测试粗甲硅烷气体,用气相色谱-质谱联用仪、感应耦合等离子体质谱仪测试精馏提纯的副产物四甲氧基硅烷.实验结果表明:在30~50℃和0.2~0.3 MPa条件下反应制备的粗甲硅烷气体中,H2、O2、Ar、N2、CH4的质量浓度分别为221.12、1.76、1.61、17.97、0.15μg/L,纯度达到99.9%;副产物四甲氧基硅烷中,金属杂质总质量浓度低于0.15μg/L,可用来制备高纯度硅溶胶;季铵碱催化三甲氧基硅烷歧化反应,反应条件温和,三甲氧基硅烷转化率96%,硅烷产率95%.催化剂易于购买,采用固定床反应器易于控制反应,易于连续加料,此工艺具有工业化生产价值.

  11. Effects of quaternary ammonium cationic modification on the sizing property of starch phosphate sizing agents%季铵醚化阳离子改性对磷酸酯淀粉浆料上浆性能的影响

    Institute of Scientific and Technical Information of China (English)

    刘志军

    2015-01-01

    为提高磷酸酯淀粉浆料的使用性能,通过改变3-氯-2-羟丙基三甲基氯化铵醚化剂对磷酸酯淀粉的投料比,制备了一系列具有不同季铵阳离子取代度的磷酸型两性淀粉。研究了其浆液性能以及对棉纤维粘附性能的影响,探讨了淀粉浆料对纯棉经纱的上浆性能。结果表明:随着季铵阳离子取代度的增加,变性淀粉浆液的ζ电位升高,粘度明显提高;季铵阳离子化变性能够进一步改善磷酸酯淀粉对棉纤维的粘附性能,提高淀粉浆料对纯棉经纱的上浆性能。%In order to improve the serviceability of starch phosphate, a series of amphoteric phosphate starch with different substitution degree of quaternary ammonium groups were prepared through varying the feed ratio of 3-chloro-2-hydroxypropyltrimethylammonium chloride to phosphate starch. The size liquid behav⁃iors of phosphate amphoteric starch, adhesion and sizing properties for cotton warp yarns were discussed. The results demonstrated that ζ-potential and viscosity of the modified starch paste and the adhesion of phos⁃phate starch for cotton fibers increased with the degree of substitution of cationic groups increasing. The modi⁃fication was favorable to the improvement of sizing properties of starch size liquid for cotton warp yarns.

  12. Gemini alkyldeoxy-D-glucitolammonium salts as modern surfactants and microbiocides: synthesis, antimicrobial and surface activity, biodegradation.

    Science.gov (United States)

    Brycki, Bogumił; Szulc, Adrianna

    2014-01-01

    Dimeric quaternary alkylammonium salts possess a favourable surface and antimicrobial activity. In this paper we describe synthesis, spectroscopic analysis, surface and antimicrobial activity as well as biodegradability of polymethylene-α,ω-bis(N,N-dialkyl-N-deoxy-D-glucitolammonium iodides), a new group of dimeric quaternary ammonium salts. This new group of gemini surfactants can be produced from chemicals which come from renewable sources. The structure of products has been determined by the FTIR and (1)H and (13)C NMR spectroscopy. The biodegradability, surface activity and antimicrobial efficacy against Escherichia coli, Staphylococcus aureus, Candida albicans, Aspergillus niger and Penicillium chrysogenum were determined. The influence of the number of alkyl chains and their lengths on surface and antimicrobial properties has been shown. In general, dimeric quaternary alkyldeoxy-D-glucitolammonium salts with long alkyl substituents show favourable surface properties and an excellent antimicrobial activity.

  13. Gemini alkyldeoxy-D-glucitolammonium salts as modern surfactants and microbiocides: synthesis, antimicrobial and surface activity, biodegradation.

    Directory of Open Access Journals (Sweden)

    Bogumił Brycki

    Full Text Available Dimeric quaternary alkylammonium salts possess a favourable surface and antimicrobial activity. In this paper we describe synthesis, spectroscopic analysis, surface and antimicrobial activity as well as biodegradability of polymethylene-α,ω-bis(N,N-dialkyl-N-deoxy-D-glucitolammonium iodides, a new group of dimeric quaternary ammonium salts. This new group of gemini surfactants can be produced from chemicals which come from renewable sources. The structure of products has been determined by the FTIR and (1H and (13C NMR spectroscopy. The biodegradability, surface activity and antimicrobial efficacy against Escherichia coli, Staphylococcus aureus, Candida albicans, Aspergillus niger and Penicillium chrysogenum were determined. The influence of the number of alkyl chains and their lengths on surface and antimicrobial properties has been shown. In general, dimeric quaternary alkyldeoxy-D-glucitolammonium salts with long alkyl substituents show favourable surface properties and an excellent antimicrobial activity.

  14. Pulmonary effects of ultrafine and fine ammonium salts aerosols in healthy and monocrotaline-treated rats following short-term exposure

    NARCIS (Netherlands)

    Cassee, F.R.; Arts, J.H.E.; Fokkens, P.H.B.; Spoor, S.M.; Boere, A.J.F.; Bree, L. van; Dormans, J.A.M.A.

    2002-01-01

    In the present study the effects of a 3-day inhalation exposure to model compounds for ambient particulate matter were investigated: ammonium bisulfate, ammonium ferrosulfate, and ammonium nitrate, all components of the secondary aerosol fraction of ambient particulate matter (PM), and carbon black

  15. Selective sampling and measurement of Cr (VI) in water with polyquaternary ammonium salt as a binding agent in diffusive gradients in thin-films technique.

    Science.gov (United States)

    Chen, Hong; Zhang, Yang-Yang; Zhong, Ke-Li; Guo, Lian-Wen; Gu, Jia-Li; Bo, Le; Zhang, Meng-Han; Li, Jian-Rong

    2014-04-30

    A diffusive gradients in thin films (DGT) device with polyquaternary ammonium salt (PQAS) as a novel binding agent (PQAS DGT) combined with graphite furnace atomic absorption spectrometry (GFAAS) was developed for the selective sampling and measurement of Cr (VI) in water. The performance of PQAS DGT was independent of pH 3-12 and ionic strength from 1 × 10(-3) to 1 molL(-1). DGT validation experiments showed that Cr (VI) was measured accurately as well as selectively by PQAS DGT, whereas Cr (III) was not determined quantitatively. Compared with diphenylcarbazide spectrophotometric method (DPC), the measurement of Cr (VI) with PQAS DGT was agreement with that of DPC method in the industrial wastewater. PQAS-DGT device had been successfully deployed in local freshwater. The concentrations of Cr (VI) determined by PQAS DGT coupled with GFAAS in Nuer River, Ling River and North Lake were 0.73 ± 0.09 μg L(-1), 0.50 ± 0.07 μg L(-1) and 0.61 ± 0.07 μg L(-1), respectively. The results indicate that PQAS DGT device can be used for the selective sampling and measurement Cr (VI) in water and its detection limit is lower than that of DPC method. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Preparation of chitosan quaternary ammonium salt and its performance test%壳聚糖季铵盐的制备及性能测试

    Institute of Scientific and Technical Information of China (English)

    黎剑辉; 庄少玲

    2015-01-01

    以壳聚糖(CTS)作为季铵盐化改性原料,以环氧丙基三甲基氯化铵(GTA)作为改性剂,在CTS的C-2位氨基上定位接上季铵盐基团得到壳聚糖季铵盐(CTS-QTS).采用FTIR、13C NMR、H1NMR、热分析(TG)表征产物CTS-QTS的结构,采用莫尔滴定法研究CTS-QTS的DS,采用凝胶渗透色谱法测定CTS和CTS-QTS的分子量,采用琼脂平板法测定CTS和CTS-QTS对金黄色葡萄球菌(S.aureus)和大肠杆菌(E.coli)的最小抑菌浓度和杀菌率,通过测试CTS-QTS对雄性小鼠和雌性小鼠急性经口毒性试验来验证CTS-QTS是否毒性类材料.研究结果表明:在pH值为7的条件下,CTS和GTA可发生温和的取代反应生成CTS-QTS,其最优反应条件为反应时间8h、反应温度80℃、CTS与GTA的摩尔比为3.CTS改性生成CTS-QTS后分子链发生了降解,分子量下降.CTS-QTS在低于200℃时分子链几乎不发生降解,具有优良的高温稳定性.CTS-QTS对S.aureus和E.coli均有抑菌和杀菌作用,对S.aureus的抑菌和杀菌作用强于对E.coli.由CTS-QTS和CTS对S.aureus和E.coli的最低抑菌浓度可知,CTS-QTS对S.aureus和E.coli的抑菌活性大于CTS.CTS-QTS对雄性小鼠和雌性小鼠急性经口毒性试验结果显示,CTS-QTS属于无毒性类材料.

  17. Catalytic Synthesis of Benzoic Acid with Quaternary Ammonium Salt%季铵盐催化氧化制备苯甲酸的研究

    Institute of Scientific and Technical Information of China (English)

    邢孔强; 朱鸿

    2007-01-01

    在甲苯氧化制备苯甲酸的实验中,利用季铵盐氯化苄基三乙铵(TEBA)作为相转移催化剂,KMnO4 作为氧化剂.考察了TEBA用量、高锰酸钾用量、反应温度、反应时间对反应的影响.得出最佳反应条件:反应温度为 90℃,反应时间2小时,KMnO4 与甲苯的摩尔比为2.5:1,季铵盐TEBA与甲苯的摩尔比为1:10时,产率达72.1%.

  18. 新型溴化烷基取代吡啶类季铵盐的合成%Synthesis of Novel Alkyl Substituted Pyridium Bromide Quaternary Ammonium Salts

    Institute of Scientific and Technical Information of China (English)

    贾瑞虹; 李银涛; 卫星星; 贾钰霞

    2015-01-01

    以烟酰胺(1)为原料,分别与1-溴代辛烷(2a)和1-溴代癸烷经烷基化反应合成了两个新型的溴化烷基取代毗啶类季铵盐(3a和3b),其结构经1H NMR,13C NMR,IR和HR-MS(MALDI)表征.在最佳反应条件[乙醇为溶剂,1 10 mmol,n(2a)∶n(1)=1.2,于78℃反应4h]下,3a收率69%.

  19. Physicochemical properties and cytotoxicity of an experimental resin-based pulp capping material containing the quaternary ammonium salt and Portland cement.

    Science.gov (United States)

    Yang, Y W; Yu, F; Zhang, H C; Dong, Y; Qiu, Y N; Jiao, Y; Xing, X D; Tian, M; Huang, L; Chen, J H

    2017-04-04

    To evaluate in vitro the physicochemical properties, cytotoxicity and calcium phosphate nucleation of an experimental light-curable pulp capping material composed of a resin with antibacterial monomer (MAE-DB) and Portland cement (PC). The experimental material was prepared by mixing PC with a resin containing MAE-DB at a 2 : 1 ratio. Cured pure resin containing MAE-DB served as control resin. ProRoot MTA and Dycal served as commercial controls. The depth of cure, degree of monomer conversion, water absorption and solubility of dry samples, calcium release, alkalinizing activity, calcium phosphate nucleation and the cytotoxicity of materials were evaluated. Statistical analysis was carried out using anova followed by Tukey's HSD test (equal variance assumed) or Tamhane test (equal variance not assumed) and independent-samples t-tests. The experimental material had a cure depth of 1.19 mm, and the mean degree of monomer conversion was 70.93% immediately post-cure and 88.75% at 24 h post-cure. The water absorption of the experimental material was between those of MTA and Dycal, and its solubility was significantly less (P material exhibited continuous calcium release and an alkalinizing power between those of MTA and Dycal throughout the test period. Freshly set experimental material, control resin and all 24-h set materials had acceptable cytotoxicity. The experimental material, MTA and Dycal all exhibited the formation of apatite precipitates after immersion in phosphate-buffered saline. The experimental material possessed adequate physicochemical properties, low cytotoxicity and good calcium phosphate nucleation. © 2017 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  20. 阳离子瓜儿胶季铵盐的制备及应用%Preparation and Application of Cationic Guar Gum Quaternary Ammonium Salt

    Institute of Scientific and Technical Information of China (English)

    孟小华

    2015-01-01

    通过对阳离子瓜尔胶的制备方法、影响因素及其在洗发香波中应用的研究,得到有机溶剂法制备阳离子瓜尔胶的最佳工艺条件如下:以异丙醇作溶剂,瓜尔胶用量10 g, CTA用量2.5 g,氢氧化钠用量0.8 g,在80℃下,持续反应9 h,所得阳离子瓜尔胶的取代度为0.075,反应效率为73%。1.0%的阳离子瓜尔胶可以使洗发香波的粘度由1650 mPa・ s增至8150 mPa・ s,洗发后使毛发显著变得柔软光滑。%This experiment has systematically studied preparation method of the cationic guar, the influence factor and the application of cationic guar gum in shampoo.The best process conditions of organic solvent preparation of cationic guar gum were as follows:using isopropyl alcohol as solvent, the amount of guar gum was 10 g, CTA dosage was 1.5 g, sodium hydroxide dosage was 0.8 g, reaction temperature was 80 ℃, time was 9 h, the degree of substitution of the cationic guar gum was 0.075 , the reaction efficiency was 73%.The 1.0%Cationic Guar may enable shampoo’viscosity from 1650 mPa・ s to 8150 mPa・ s, and after washed with it the hair was softer and smoother remarkable.

  1. CO2 capture using semi-clathrates of quaternary ammonium salt: structure change induced by CO2 and N2 enclathration.

    Science.gov (United States)

    Chazallon, Bertrand; Ziskind, Michael; Carpentier, Yvain; Focsa, Cristian

    2014-11-26

    Semi-clathrates of tetrabutylammonium bromide (TBAB) are investigated for their potential application in the CO2 capture context based on hydrate technology. The three-phase lines of semi-clathrates of CO2-TBAB-H2O and N2-TBAB-H2O are established simultaneously with their structure using in situ Raman scattering performed at high pressure. The preferred crystal phase obtained at ambient pressure from solutions of 5 and 40 wt % TBAB initial concentrations is shown to change upon enclathration of CO2 or N2, or by applying a higher pressure on the system. Deep in the stability field, metastable hydrate phases are occurring at the onset of the formation and correspond to the ones expected under ambient pressure conditions. Depending on the pressure, they progressively transformed into the most stable ones when approaching equilibrium and dissociation points. Besides, it is shown that a 5 wt % TBAB original solution forms preferentially a mixed structure of both type B and type A at low gas pressure with CO2 as the guest gas. A new structure is spectroscopically characterized at pressures higher than ∼2 MPa CO2. Type A is demonstrated to be stable at 5 wt % initial TBAB concentration with N2 as the guest molecule and pressure between 8 and 12 MPa. These structural data address new insights on the relationship between the hydrophilic-anion and hydrophobic-cation intercalation with a guest gas producing hydrophobic interaction in a distorted water lattice.

  2. COPOLYMERIZATION OF CARBON DIOXIDE AND CYCLOHEXENE OXIDE CATALYZED BY ALUMINUM PORPHYRIN-QUATERNARY AMMONIUM SALT IN THE PRESENCE OF BULKY LEWIS ACID

    Institute of Scientific and Technical Information of China (English)

    Yu-sheng Qin; Xian-hong Wang; Xiao-jiang Zhao; Fo-song Wang

    2008-01-01

    Chloro(5,10,15,20-tetraphenyl-porphyrinato)-aluminum/tetraethylammonium bromide (Et4NBr) in combinationwith bulky Lewis acid was used for the copolymerization of CO2 and cyclohexene oxide (CHO). Bulky Lewis acid havingsubstituents at the ortho positions of the phenolate ligands, like methylaluminum bis(2,6-di-tert-butyl-4-methylphenolate),significantly shortened the induction period and raised the catalytic activity, the corresponding turnover frequency reached44.9 h-1 in 9 h, which was 23.8% higher than that from (TPP)AICI/EtaNBr binary catalyst. The resulting polycarbonate hascarbonate linkage over 93% with number average molecular weight of (4.5-6.5)×103 and polydispersity index below 1.10.

  3. 芳酮季铵盐光产碱剂的合成与表征%Synthesis of Quaternary Ammonium Salt Photobase Generator with Arone

    Institute of Scientific and Technical Information of China (English)

    钟荣; 杨建文; 曾兆华; 陈用烈

    2006-01-01

    以苯乙酮、对甲氧基苯乙酮、萘乙酮、4-甲基二苯甲酮生色团为母体、杂环叔胺三亚乙基二胺、吡啶、3-甲基吡啶和四苯硼盐为原料,合成了12个四苯硼季铵盐光产碱剂,产物经熔点测量、元素分析、FT-IR、1H NMR表征,考察了其吸收光谱等特性.

  4. Synthesis and biological activities of some homopiperazine quaternary ammonium%一些高哌嗪类季铵盐的合成及生物活性研究

    Institute of Scientific and Technical Information of China (English)

    农娟; 郑志兵; 苏桂发; 陶杰; 覃江克; 唐煌; 邓业成

    2012-01-01

    Eight 1-methylhomopiperazine quaternary ammoniums 4a ~4h were synthesized via the esterification of 10-hydroxy-2-de-cenoic acid with acetic anhydride, acylation with 1 -methylhomopiperazine, then quatemarization with halohydrocarbon. The structures of the synthesized compounds were confirmed by IR,NMR and MS. Their inhibitory activities on Acetylcholinesterase( AchE) and butyrylcholinesterase ( BuchE) , fungicidal activity against Staphylococcus aureus were investigated. The results indicated that compounds 4 were capable of inhibiting AchE and BuchE in vitro with moderate to good activities,among which 4c on AchE and 4g on BuchE had the highest inhibitory activities,with the /C50being 2. 56 and 6.62 μmol/L, respectively. In addition,compounds 4e and 4h possessed a fungicidal activity against Staphylococcus aureus at a test concentration of 0.25 g/L%将蜂王酸经醋酐酯化后与1-甲基高哌嗪发生酰化后再季铵化,合成了8个未见文献报道的高哌嗪类季铵盐4a~4h,所有化合物的结构经IR,1H NMR,13C NMR和MS分析确认.考察了这些化合物与乙酰胆碱酯酶(AchE)、丁酰胆碱酯酶(BuchE)、金黄色葡萄球菌的抑制作用,结果表明:化合物4对AchE和BuchE具有较好的抑制活性,其中4c对AchE的抑制效果最好,其IC50 =2.56 μmol/L;4g对BuchE的抑制效果最好,IC50 =6.62 μmol/L;化合物4e,4h在浓度为0.25g/L时对金黄色葡萄球菌(Staphylococcus aureus)的抑菌效果较好.

  5. Preparation of two ester-containing Gemini quaternary ammonium softener and its properties%双酯基Gemini季铵盐柔软剂的制备及性能

    Institute of Scientific and Technical Information of China (English)

    娄平均; 朱红军; 丁徽; 牛华

    2011-01-01

    A di-ester Gemini quaternary ammonium softener( DEGOS) is prepared with dimethyl stearic acid ethyl tertiary amine and 1,3-dichloro-2-propanol as raw materials. The optimum synthesis conditions ara determined via orthogonal experiments as follows∶reaction at 80 ℃ for 12 hours with n( 1 , 3-dichloro-2-propanol) ∶ n ( dimethyl stearic acid ethyl tertiary amine) = 1 ∶ 2.1and ethanol of 40% , and the yield reaches 89.3%. The product is characterized by FTIR, elemental analysis and 1H-NMR, and its application properties are studied. The results show that the product features good surface activity with surface tension of 35.9 mN/m, critical micelle concentration of 0.039 mmol/L and Krafft point of - 3.41 ℃, good softening property similar to that of commercial softener D1821, and good rewetting property and biodegradability, as well as low influence on whiteness of the fabric.%以二甲基硬脂酸乙酯基叔胺和l,3-二氯-2-丙醇为原料,合成了一种双酯基Gemini季铵盐织物柔软剂(DEGQS).通过正交试验考察了反应的影响因素,确定优化工艺条件为:n(1,3-二氯-2-丙醇):n(二甲基硬脂酸乙酯基叔胺)=1:2.1,反应温度80℃,W(乙醇)=40%(占反应物总量的质量分数),反应时间12 h,在该条件下目标产物的收率达到89.3%.通过FTIR、元素分析和1H-NMR对DEGQS进行表征,并研究其应用性能,结果表明,该柔软剂的表面张力35.9 mN/m,临界胶束浓度0.039 mmol/L,Krafft点为-3.41℃,表面活性较好,柔软性能与D1821基本相当,具有优良的再润湿性和生物降解性能,对织物的白度影响较小.

  6. Base stable quaternary ammonium ionic liquids

    OpenAIRE

    Lethesh, Kallidanthiyil Chellappan; Dehaen, Wim; Binnemans, Koen

    2014-01-01

    Ionic liquids with the bis(2-ethylhexyl)dimethylammonium cation, [BEDMA]+, were prepared by a halide-free route starting from the readily available secondary amine bis(2-ethylhexyl)amine. The following anions were considered: chloride, bromide, iodide, nitrate, hydrogensulphate, dihydrogenphosphate, formate, acetate, propionate, trifluoroacetate, methyl sulphate, methanesulphonate, tosylate, isonicotinate, nicotinate and picolinate. Several of the compounds are room-temperature ionic liquids,...

  7. 酱油中铵盐含量的监测与来源分析%Surveillance and analysis on the quantity and origin of ammonium salt in soy sauce

    Institute of Scientific and Technical Information of China (English)

    林崇昌; 司徒小玉; 邓秀燕; 吴灿斌

    2011-01-01

    Objective To investigate the quantity and origin of ammonium salt in soy sauce produced in Kaiping city,and provide references for the quality control of soy sauce production.Methods Detecting the contents of ammonium salt and amino acid nitrogen in soy sauce, calculating the proportion and the qualified rate of different types of ammonium salt,and detecting the contents of ammonia nitrogen in raw materials of caramel and ammonium salt in molasses.Results The difference between the qualified rate of ammonium salt in semi-finished products and end products of soy sauce ( 100% and 91.3% respectively) was of statistical significance (x2 = 4.3, 0.01 < P < 0.05 ).The difference on the qualified rate of ammonium salt between light soy sauce ( 100% ) and dark soy sauce (72.7% ) was of statistical significance (x2 = 17.7,P <0.01 ).Ammonia nitrogen contents in caramel were in the range of 0.02%-0.04% and all qualified, while ammonia nitrogen contents in molasses were 0.05-0.25 g/100 ml.Conclusion The contents of ammonia nitrogen in some species of soy sauce produced in Kaiping city were higher than the upper limits, which was the result of excessive ammonium salt in molasses.%目的 研究开平市产酱油中铵盐含量及其污染来源,为酱油生产过程质量控制提供参考依据.方法 检测酱油中的铵盐和氨基酸态氮含量,计算铵盐比率和合格率;检测原料焦糖色中氨氮含量和糖蜜中铵盐含量.结果 半成品酱油铵盐合格率(100%)和成品酱油铵盐合格率(91.3%)差异有统计学意义(x2=4.3,0.01<P<0.05);成品酱油中生抽酱油铵盐合格率(100%)和老抽酱油铵盐合格率(72.7%)差异有统计学意义(x2=17.7,P<0.01);焦糖色中氨氮含量在0.02%~0.04%之间,全部合格;糖蜜中铵盐含量在0.05~0.25g/100 ml之间.结论 开平市产部分酱油品种铵盐含量超标,是加入铵盐含量高的糖蜜导致.

  8. Synthesis of Tertiary and Quaternary Amine Derivatives from Wood Resin as Chiral NMR Solvating Agents

    Directory of Open Access Journals (Sweden)

    Tiina Laaksonen

    2015-11-01

    Full Text Available Chiral tertiary and quaternary amine solvating agents for NMR spectroscopy were synthesized from the wood resin derivative (+-dehydroabietylamine (2. The resolution of enantiomers of model compounds [Mosher’s acid (3 and its n-Bu4N salt (4] (guests by (+-dehydroabietyl-N,N-dimethylmethanamine (5 and its ten different ammonium salts (hosts was studied. The best results with 3 were obtained using 5 while with 4 the best enantiomeric resolution was obtained using (+-dehydroabietyl-N,N-dimethylmethanaminium bis(trifluoromethane-sulfonimide (6. The compounds 5 and 6 showed a 1:1 complexation behaviour between the host and guest. The capability of 5 and 6 to recognize the enantiomers of various α-substituted carboxylic acids and their n-Bu4N salts in enantiomeric excess (ee determinations was demonstrated. A modification of the RES-TOCSY NMR pulse sequence is described, allowing the enhancement of enantiomeric discrimination when the resolution of multiplets is insufficient.

  9. 季铵基吸附树脂的合成及其在甜菊甙提取分离中的应用%SYNTHESIS OF POLYMERIC ADSORBENTS WITH QUATERNARY AMMONIUM GROUPS AND THEIR APLICATION IN EXTRACTION AND SEPARATION OF STEVIA GLYCOSIDES

    Institute of Scientific and Technical Information of China (English)

    施荣富; 史作清; 范云鸽; 王春红; 路延龄; 何炳林

    2001-01-01

    研究了由工业二乙烯苯聚合得到的大孔树脂进行氯甲基化的可行性,考察了聚合物孔结构催化剂用量、反应温度和时间等因素对氯甲基化反应的影响,由氯甲基化树脂制备了强极性季铵基吸附剂。并研究了合成的季铵基吸附剂对甜叶菊提取物中甜菊甙及色素的吸附-脱附性能,发现该吸附剂对甜菊甙与色素的吸附-脱附性能完全不同,因而可用该吸附剂制备高品质的甜菊甙。%The feasibility of chloromethylation of macroporous resin madefrom technical divinylbenzene was studied. The factors that effect the chloromethylating reaction, such as the pore structure of the resin, the reaction condition and so on were investigated. Strongly basic adsorbents with quaternary ammonium group were prepared from the chloromethylated resin. The adsorbents with quaternary ammonium group possess definitely different adsorption-desorption property for stevia glycosides and coloring matters in the extract of stevia Rebaudiana Bertoni, and the adsorbents can be used to produce stevia glycosides with high quality.

  10. Synthesis, micellisation and interaction of novel quaternary ammonium compounds derived from l-Phenylalanine with 1,2-dipalmitoyl-sn-glycero-3-phosphocholine as model membrane in relation to their antibacterial activity, and their selectivity over human red blood cells.

    Science.gov (United States)

    Joondan, Nausheen; Caumul, Prakashanand; Akerman, Matthew; Jhaumeer-Laulloo, Sabina

    2015-02-01

    A series of quaternary ammonium compounds (QUATS) derived from l-Phenylalanine have been synthesized and their antibacterial efficiencies were determined against various strains of Gram-positive and Gram-negative bacteria. The antibacterial activity increased with increasing chain length, exhibiting a cut-off effect at C14 for Gram-positive and C12 for Gram-negative bacteria. The l-Phenylalanine QUATS displayed enhanced antibacterial properties with a higher cut-off point compared to their corresponding l-Phenylalanine ester hydrochlorides. The CMC was correlated with the MIC, inferring that micellar activity contributes to the cut-off effect in antibacterial activity. The hemolytic activities (HC50) of the QUATS against human red blood cells were also determined to illustrate the selectivity of these QUATS for bacterial over mammalian cells. In general, the MIC was lower than the HC50, and assessment of the micellar contribution to the antibacterial and hemolytic evaluation in TBS as a common medium confirmed that these QUATS can act as antibacterial, yet non-toxic molecules at their monomer concentrations. The interaction of the QUATS with the phospholipid vesicles (1,2-dipalmitoyl-sn-glycero-3-phosphocholine, DPPC) in the presence of 1-anilino-8-naphthalene sulfonate (ANS) and 1,6-diphenyl-1,3,5-hexatriene (DPH) as fluorescence probes showed that the presence of the quaternary ammonium moiety causes an increase in hydrophobic interactions, thus causing an increase in antibacterial activity.

  11. 新型双甲基丙烯酰季铵盐单体对基质金属蛋白酶活性的影响%Inhibitory effect of a novel crosslinking quaternary ammonium methacrylates on matrix metalloproteinases

    Institute of Scientific and Technical Information of China (English)

    刘宁; 李芳; 张凌; 陈宇江; 陈吉华

    2013-01-01

    目的 研究新型双甲基丙烯酰季铵盐单体对基质金属蛋白酶活性的影响,探索提高牙本质粘接耐久性的新方法.方法 使用荧光试剂盒检测质量分数分别为1%、3%、5%和7%的双甲基丙烯酰季铵盐单体[2-甲基丙烯酰氧乙基-正十二烷基-甲基溴化铵(2-methacryloxylethyl dodecylmethyl ammonium bromide,MAE-DB)]对游离型基质金属蛋白酶8(matrix metalloproteinase-8,MMP-8)活性的影响,用酶标仪每隔20 min检测荧光值至3h,以试剂盒提供的抑制剂1,10-二氮菲作为抑制剂对照组.将24颗离体牙制备的牙本质试件完全脱矿后获得胶原纤维试件,通过随机数字表法分成3组(每组50个),分别浸泡于人工唾液、含7% MAE-DB单体的人工唾液以及含2%氯己定的人工唾液中,经冷热循环5000和10 000次后,检测胶原纤维试件拉伸强度的变化,评价MAE-DB单体对结合型基质金属蛋白酶的作用.透射电镜观察冷热循环后各组胶原纤维试件的形态.结果 1 h 3% MAE-DB单体对MMP-8活性的抑制百分比为99.53%,显著高于抑制剂对照组(95.71%)(P<0.05).冷热循环5000次和10 000次后,含7% MAE-DB组胶原纤维试件的拉伸强度[分别为(10.66±2.12)和(8.89±1.89) MPa]分别显著高于人工唾液组[分别为(7.43±2.27)和(5.46±1.76) MPa]和含2%氯己定人工唾液组[分别为(9.34±2.53)和(7.67 ±2.20) MPa] (P<0.05).透射电镜显示7% MAE-DB组胶原纤维微观结构完整,而人工唾液组胶原纤维微观结构紊乱.结论 双甲基丙烯酰季铵盐单体MAE-DB可有效抑制MMP-8的活性,保护胶原纤维,降低胶原纤维在老化过程中的酶解.%Objective To evaluate the anti-matrix metalloproteinase (MMP) activity of a novel crosslinking quaternary ammonium methacrylates,2-methacryloxylethyl dodecylmethyl ammonium bromide (MAE-DB).Methods The effects of MAE-DB at different concentrations (1%,3%,5%,7%) on soluble matrix metalloproteinase-8

  12. Hydrothermal Synthesis of Mesoporous Nanocrystalline Tetragonal ZrO2 Using Dehydroabietyltrimethyl Ammonium Bromine

    Directory of Open Access Journals (Sweden)

    Peng Wang

    2015-01-01

    Full Text Available Mesoporous nanocrystalline tetragonal zirconias were successfully synthesized through a hydrothermal method using a novel bioresource-derived quaternary ammonium salt, dehydroabietyltrimethyl ammonium bromine (DTAB, as a templating agent. The templating agent provides a surface area (242.02 m2/g, high pore volume (0.53 cm3/g, and large average pore diameter (7.65 nm, which suggests that DTAB is a good candidate for mesostructure synthesis. The hydrothermal treatments give the materials improved thermal stabilities because of the generation of tetragonal nanocrystallites that are more stable than the bulk amorphous ones in the hydrothermal process. However, because of the absence of stabilizers, the sizes of the crystallites of the as-synthesized sample increase gradually with increasing calcination temperature. As the crystalline size of the sample rises to 25 nm, the nanocrystallites become too large to integrate well together, causing the well-organized mesostructure to collapse.

  13. Complete Conversion of PbI2 to Methyl Ammonium PbI3 Improves Perovskite Solar Cell Efficiency.

    Science.gov (United States)

    Wang, Lili; Lin, Wei-Chun; McCleese, Christopher; Kovalsky, Anton; Zhao, Yixin; Burda, Clemens

    2017-01-04

    One major disadvantage to the two-step deposition method of perovskite films is the incomplete conversion from PbI2 to perovskite resulting in the presence of a thick PbI2 layer, which hinders charge carrier transportation. In this study, a quaternary ammonium salt has been used to manipulate the crystallization of PbI2 in the first deposition step, which leads to facile incorporation of the methylammonium iodide into the Pb-I lattice and promotes the conversion of PbI2 to perovskite leading to improved device performance. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. 新型有机硅季鏻盐抗菌剂的合成及应用研究%Synthesis and application of novel silicone quaternary phosphonium salt antibacterial agent

    Institute of Scientific and Technical Information of China (English)

    王萌; 闵洁; 籍海燕

    2013-01-01

    R-chloropropyl triethoxysilane quaternary phosphonium salt was synthesized through SN2 reaction, using triphenylphosphine and γ-chloropropyl triethoxysilane as raw materials. The effects of the type and amount of solvent, reaction temperature, reaction time and the ratio of reactants on conversion rate of reaction were investigated. The product was characterized by the structure using FTIR and NMR. The results showed that the optimal reaction conditions were as follows: reaction medium was 40 ml_ benzyl alcohol, molar ratio of triphenylphosphine to γ-chloropropyl triethoxysilane was 1:1.1, reaction temperature was 135℃ and reaction time was 27 h. The cotton fabric was treated with quaternary phosphonium salt by padding method. The inhibition rates of the treated cotton fabric to E. coli and S. aureus were both more than 80%, which indicated that the quaternary phosphonium salt could increase the antibacterial property of the fabric. Furthermore, the results showed that the treated fabric had certain washing durability.%以三苯基膦和氯丙基三乙氧基硅烷为原料,通过SN2反应合成氯丙基三乙氧基硅烷季鏻盐.考察了溶剂种类和用量、反应温度、反应时间、反应物配比等因素对反应转化率的影响,采用红外光谱和核磁共振谱表征了产物.结果表明,合成有机硅季鏻盐的最佳工艺为:以40 mL苯甲醇为溶剂,n(三苯基膦)∶n(硅烷)=1∶1.1,135℃反应27 h.通过浸轧将产品用于棉织物的整理,测得整理织物对大肠杆菌和金黄色葡萄球菌的抑菌率均在80%以上,说明有机硅季鳞盐确实能够提高织物的抗菌性能.研究还表明,整理织物具有一定的耐洗性.

  15. Counterion influence on the vibrational wavenumbers in ternary and quaternary metal hydride salts, A2MH6 (A = alkali metal, alkaline earth, and lanthanides; M = Ir, Fe, Ru, Os, Pt, Mn).

    Science.gov (United States)

    Gilson, Denis F R; Moyer, Ralph O

    2012-02-06

    The wavenumbers of the ν(3) metal-hydrogen stretching mode (T(1u)) in the IR spectra of both ternary and quaternary hexahydrido salts of transition metals from groups 7 to 10 ([Mn(I)H(6)](5-), [Fe(II)H(6)](4-), [Ru(II)H(6)](4-), [Os(II)H(6)](4-), [Ir(III)H(6)](3-), and [Pt(IV)H(6)](2-)) depend linearly upon the ionization energies of the counterions (alkali metal, alkaline earth, and lanthanide) with a separate line for each metal. This relationship provides quantitative support for the charge-transfer mechanism for explaining the stabilities of these compounds.

  16. Ligand-enabled multiple absolute stereocontrol in metal-catalysed cycloaddition for construction of contiguous all-carbon quaternary stereocentres.

    Science.gov (United States)

    Ohmatsu, Kohsuke; Imagawa, Naomichi; Ooi, Takashi

    2014-01-01

    The development of a general catalytic method for the direct and stereoselective construction of contiguous all-carbon quaternary stereocentres remains a formidable challenge in chemical synthesis. Here, we report a highly enantio- and diastereoselective [3+2] annulation reaction of 5-vinyloxazolidinones and activated trisubstituted alkenes catalysed by a palladium complex bearing a newly devised phosphine ligand with a chiral ammonium salt component, which enables the single-step construction of three contiguous stereocentres, including vicinal all-carbon quaternary stereocentres, in a five-membered heterocyclic framework. This stereoselective cycloaddition protocol relies on the remarkable ability of the chiral ligand to rigorously control the absolute stereochemistry of each chiral centre associated with the multiple bond-forming events, and provides a reliable catalytic process for the asymmetric synthesis of densely functionalized pyrrolidines.

  17. Process optimization of rare earth and aluminum leaching from weathered crust elution-deposited rare earth ore with compound ammonium salts

    Institute of Scientific and Technical Information of China (English)

    何正艳; 张臻悦; 余军霞; 徐志高; 池汝安

    2016-01-01

    In order to intensify the leaching process of rare earth (RE) and reduce the impurities in the leachate, ammonium chloride (NH4Cl) and ammonium nitrate (NH4NO3) were mixed as a compound leaching agent to treat the weathered crust elution-deposited RE ore. Effects of molar ratio of NH4Cl and NH4NO3, ammonium (NH4+) concentration, leaching agent pH and flow rate on the leaching process of RE were studied and evaluated by the chromatographic plate theory. Leaching process of the main impurity alu-minium (Al) was also discussed in detail. Results showed that a higher initial ammonium concentration in a certain range could en-hance the mass transfer process of RE and Al by providing a driving force to overcome the resistance of diffusion. pH almost had no effects on the mass transfer efficiency of RE and Al in the range of 4 to 8. The relationship between the flow rate and height equiva-lent to a theoretical plate (HETP) could fit well with the Van Deemter equation, and the flow rate at the lowest HETP was determined. The optimum conditions of column leaching for RE and Al were 1:1 (molar ratio) of NH4Cl and NH4NO3, 0.2 mol/L of ammonium concentration, pH 4–8 of leaching agent and 0.5 mL/min of flow rate. Under this condition, the mass transfer efficiency of RE was improved, but no change was observed for Al compared with the most widely used ammonium sulfate. Moreover, the significant dif-ference value (around 20 mL) of retention volume at the peak concentration between RE and Al provided a possibility for their sepa-ration. It suggested the potential application of the novel compound leaching agent (NH4Cl/NH4NO3). It was found that the relative concentration of RE in the leachate could be easily obtained by monitoring the pH of leachate.

  18. Application of chitosan ammonium salt to inkjet printing of cotton fabric%壳聚糖季铵盐在棉织物喷墨印花中的应用

    Institute of Scientific and Technical Information of China (English)

    卜广玖; 朱锋; 王潮霞

    2011-01-01

    采用壳聚糖季铵盐对棉织物进行改性处理,探讨了改性处理对棉织物水性颜料墨水喷墨印花性能的影响.结果表明,经壳聚糖季铵盐改性后,棉纤维表面变得光滑,并形成一层薄膜;壳聚糖季铵盐改性可提高喷墨印花织物的K/S值,当壳聚糖季铵盐用量为0.8%时,K/S值由原先的3.20提高到4.87;喷墨印花的防渗化性能得到增强,印花清晰度提高,打印0.5 mm线条时,处理后织物经纬向的实际线宽清晰度分别提高16.5%和12.6%;改性后印花棉织物的弯曲刚度和弯曲滞后矩略有增加,织物手感略微变差.%Cotton fabric is modified with chitosan ammonium salt followed by pigment inkjet printing. Influence of modification on water-based pigment inkjet printing properties of cotton fabric is discussed. The results show that the fiber surface becomes smooth and is covered with a film after chitosan ammonium salt modification. K/S value of the cotton printings increases from 3.20 to 4.87 when modified with 0.8% of chitosan ammonium salt. Anti-flushing property is enhanced, printing definition is improved, and the accuracies of lines in warp and weft directions increase by 16.5% and 12.6% respectively when printing 0.5 mm line. The modified cotton printings feature a little increase in bending stiffness and lag bending moment and a slight decrease in handle.

  19. Salt-free dyeing properties of cotton fabric modified with reactive quaternary ammonium salt of chitosan (NMA-HTCC)%反应性壳聚糖季铵盐改性棉织物的无盐染色性能

    Institute of Scientific and Technical Information of China (English)

    张伟; 周静洁

    2014-01-01

    采用低分子质量壳聚糖与2,3-环氧丙基三甲基氯化铵反应,合成2-羟丙基三甲基氯化铵壳聚糖(HTCC),再将HTCC与N-羟甲基丙烯酰胺反应,合成带有反应性基团的水溶性O-甲基丙烯酰胺壳聚糖季铵盐(NMA-HTCC),可直接与棉纤维素形成共价键.基于NMA-HTCC良好的水溶性和反应活性,将其应用于棉织物的改性,探索改性的较佳工艺条件,并研究改性前后棉织物活性染料无盐染色性能.结果表明,NMA-HTCC改性棉织物的优化工艺为:NMA-HTCC 7 g/L,处理温度60℃,处理时间50 min,此时棉织物无盐染色的固色率和K/S值较好;NMA-HTCC有明显的促染作用,既能实现棉织物的无盐染色,又能在不降低水洗牢度和摩擦牢度的前提下改善织物的染色效果.

  20. 氧化镁铵盐法制备高纯过氧化镁%Preparation of High Purity Magnesium Peroxide by Magnesia and Ammonium Salt Solutions

    Institute of Scientific and Technical Information of China (English)

    朱海丽; 吴小王

    2011-01-01

    在氯化铵溶液体系中,以氧化镁,过氧化氢为原料,制备高纯过氧化镁。研究表明采用氧化镁活性大于100,氯化铵/氧化镁不小于10%,过氧化氢:氧化镁不小于4∶1,反应温度大于40℃情况下,反应时间不小于30 min,可制备出纯度大于90%的过氧化镁。%In ammonium chloride solution,magnesium oxide and hydrogen peroxide as raw material,high purity magnesium peroxide was prepared.The results showed that using magnesium oxide activity was greater than 100,ammonium chloride and magnesium oxide was not less than 10%,hydrogen peroxide to magnesium oxide was not less than 4:1,the reaction temperature was higher than 40 ℃,and the reaction time was not less than 30 min,with magnesium peroxide purity above 90%.

  1. A Composite Membrane of Caesium Salt of Heteropolyacids/Quaternary Diazabicyclo-Octane Polysulfone with Poly (Tetrafluoroethylene for Intermediate Temperature Fuel Cells

    Directory of Open Access Journals (Sweden)

    Keith Scott

    2012-07-01

    Full Text Available Inorganic-organic composite electrolyte membranes were fabricated from CsXH3−XPMo12O40 (CsPOMo and quaternary diazabicyclo-octane polysulfone (QDPSU using a polytetrafluoroethylene (PTFE porous matrix for the application of intermediate temperature fuel cells. The CsPOMo/QDPSU/PTFE composite membrane was made proton conducting by using a relatively low phosphoric acid loading, which benefits the stability of the membrane conductivity and the mechanical strength. The casting method was used in order to build a thin and robust composite membrane. The resulting composite membrane films were characterised in terms of the elemental composition, membrane structure and morphology by EDX, FTIR and SEM. The proton conductivity of the membrane was 0.04 S cm−1 with a H3PO4 loading level of 1.8 PRU (amount of H3PO4 per repeat unit of polymer QDPSU. The fuel cell performance with the membrane gave a peak power density of 240 mW cm−2 at 150 °C and atmospheric pressure.

  2. Catalytic Asymmetric Synthesis of Both Enantiomers of 4‑Substituted 1,4-Dihydropyridines with the Use of Bifunctional Thiourea-Ammonium Salts Bearing Different Counterions

    Directory of Open Access Journals (Sweden)

    Kohzo Yoshida

    2010-11-01

    Full Text Available Organoammonium salts composed of a Brønsted acid and an anilinothiourea promoted the Michael addition of β-keto esters and α,β-unsaturated aldehydes in the presence of primary amines to give functionalized 1,4-dihydropyridines enantioselectively. With the use of the different Brønsted acids such as DFA and HBF4 with the same bifunctional thiourea, both enantiomers of 4-substituted 1,4-dihydropyridine were synthesized from the same starting materials.

  3. 由铵盐制备高纯氟化钡的工艺研究%Preparation technology of high purity barium fluoride from ammonium salt

    Institute of Scientific and Technical Information of China (English)

    许春晓; 刘晓红; 柯春兰; 章小明

    2011-01-01

    以氟化铵和氯化钡为原料,采用沉淀法制备了氟化钡.反应温度为25℃,反应时间为60min,氯化钡初始质量分数为10%,氟化铵与氯化钡物质的量比为2.2,m(洗水):m(滤饼)=10:1,可制备出纯度达99%以上的氟化钡.XRD谱图表明,样品氟化钡的所有衍射峰均与标准立方相氟化钡吻合,属立方晶系.该工艺流程简单,经济效益好.%Barium fluoride (BaF2 ) was prepared by precipitation method with ammonium fluoride and barium chloride as raw materials. BaF2 with purity of more than 99% can be prepared when reaction temperature is 25 ℃ ,reaction time is 60 rnin,initial mass fraction of barium chloride is 10% ,amount-of-substance ratio of ammonium fluoride to barium chloride is 2.2,and the mass ratio of washing water amount to filter cake amount = 10: 1. XRD pattern showed that all the diffraction peaks of barium fluoride sample were consistent with the standard cubic barium fluoride. Therefore it belongs to the cubic crystal system. The technology has short flow route and good economic benefits.

  4. Synthesis and vulcanization activity of N-butylxanthate-tetramethyl quaternary ammonium ionic liquids as vulcanization accelerator%正丁基黄原酸-四甲基季铵盐离子液体的合成及硫化促进性能研究∗

    Institute of Scientific and Technical Information of China (English)

    游兴均; 周元林; 曾燕飞

    2014-01-01

    通过以正丁醇、CS2、NaOH 为原料,以水作溶剂合成正丁基黄原酸钠盐。再将合成的正丁基黄原酸钠盐溶解在甲醇中,加入四甲基氯化铵在室温条件下搅拌反应得到正丁基黄原酸-四甲基季铵盐离子液体(ILS),产物结构通过质谱(MS),元素分析,核磁(1 H-NMR)确定。将所得到的产品作为硫化促进剂用于天然橡胶(NR),讨论了不同的 ILS 用量、不同的硫化温度和不同的硫化时间对天然橡胶制品的性能的影响,并与传统硫化促进剂 TMTD,CBS 作了对比实验,结果表明正丁基黄原酸-四甲基季铵盐离子液体对天然橡胶(NR)具有较好的低温、高效的硫化促进效果。%Using n-butyl alcohol,CS2 and NaOH as starting materials,and water as a solvent,sodium n-butyx-anthate was synthesized.The synthetic Sodium n-butyxanthate was dissolved in methanol,afterward,tetram-ethylammonium chloride in methanol was added.After completion of the reaction,the N-butylxanthate-tetram-ethyl quaternary ammonium ionic liquids (ILS)will be obtained.The structure of the product was confirmed by mass spectrometry (MS),elemental analysis and 1 H-NMR.The product was used as a vulcanization accelerator of natural rubber (NR),and compared with the traditional vulcanization accelerator TMTD,CBS.The results show that the n-butyxanthate-tetramethyl quaternary ammonium ionic liquids has excellent performance as vul-canization accelerator for NR,worth of further investigation.

  5. Molten Salt Synthesis, Crystal Structure and Optical Properties of a Novel Quaternary Metal Selenide, K2AgIn3Se6

    Institute of Scientific and Technical Information of China (English)

    Guo, Hong-You(郭洪猷); Wang, Zhi-Xia(王志霞); Shu, Gui-Ming(舒桂明); Wang, Ru-Ji(王如骥); Zhang, Li-Dan(张丽丹); Wang, Ping(王平)

    2004-01-01

    K2AgIn3Se6 was synthesized by a molten-salt (alkali-metal polyselenide flux) reaction at 500 ℃. The orange red granular crystal crystallizes in monoclinic space group C2/c with cell parameters, a=1.16411(7) nm, b=1.16348(8) nm, c=2.14179(12) nm, V=2.8740(9) nm3, and Z=8. The crystal has a new two-dimensional structure containing 2∞[AgIn3Se6]2- anionic layers separated by K+ cations and the 2∞[AgIn3Se6]2- layer is constructed with corner-shared [AgSe4] and [InSe4] tetrahedra. The optical band gap of K2AgIn3Se6 was determined to be ca. 2.9 eV by UV/vis/NIR diffuse reflectance spectra.

  6. Singlet Mechanism for Trans → Cis Photoisomerization of Quaternary Salts of 4-Substituted 4'-Azastilbenes (R = CN, H, CH3, and OCH3) and their Quinolinium Analogues. VIII

    Science.gov (United States)

    Görner, H.; Fojtik, A.; Wróblewski, J.; Currell, L. J.

    1985-05-01

    The trans → cis photoisomerization of a series of substituted stilbazolium salts (At+X- , At+: trans-1-alkyl-4-[4-R-styryl]-pyridinium and -quinolinium, R = CN. H, CH3 and OCH3, X- = I and ClO4-) was studied by laser flash photolysis and steady state irradiation measurements. The quantum yields of cis ⇄ trans photoisomerization (ϕc → t and ϕt → c ) and of fluorescence of the trans isomers (ϕf) were determined in several solvents at room temperature and at low temperatures in mixtures of either 2-methyltetrahydrofuran-dichloromethane or ethanolmethanol (E-M). In polar solvents at room temperature ϕt → c is substantial ( ≧ 0.3) and ϕf is small (10-3-10-2). Competition of fluorescence and an activated step in the trans → cis pathway is indicated by the effects of temperature on ϕf and ϕt → c (activation energy: 2 - 3 kcal/mol). A transient, observed only at low temperatures (lifetime τT > 0.5 ms in E-M below -170°C), is assigned to the lowest triplet state with trans configuration. On the basis of the effects of temperature on ϕf, ϕt → c , and the triplet yield and those of quenchers on ϕf and ϕt → c , involvement of the triplet state in the twisting process at room temperature is excluded. Therefore, a singlet mechanism is suggested for the trans → cis photoisomerization of the stilbazolium salts examined. Significant reduction of ϕt → c for iodides in solvents of moderate polarity, where ion pairs are present, is accounted for by photoinduced electron transfer in competition to trans → cis photoisomerization.

  7. Equilibrium studies of sodium-ammonium potassium-ammonium, and calcium-ammonium exchanges on clinoptilolite zeolite

    Energy Technology Data Exchange (ETDEWEB)

    Jama, M.A.; Yuecel, H. (Middle East Technical Univ., Ankara (Turkey))

    1989-12-01

    Forward and reverse ion-exchange isotherms for the binary sodium-ammonium, potassium-ammonium, and calcium-ammonium systems on clinoptilolite have been measured in aqueous solutions at a total concentration of 0.1 equiv/dm{sup 3} and at 298 K. Prior to exchange experiments it was attempted to prepare homoionic forms of the zeolite by exhaustive treatments with appropriate salt solutions of cations. With no binary exchanges, full replacement of the cation by the ammonium ion is observed, which conflicts with some earlier work on clinoptilolite. Despite the observed partial exchange levels, clinoptilolite shows a very high preference for ammonium ion over sodium and calcium but not over potassium. Thermodynamic values for the exchanges were calculated and compared with data in the literature. Both the selectivity and thermodynamic affinity sequence, in agreement with previous work reported in the literature, are K{sup +} > NH{sub 4}{sup +} > Na{sup +} > Ca{sup 2+}.

  8. Modification of zeolities with ammonium fluoride

    Energy Technology Data Exchange (ETDEWEB)

    Rosinski, E.J.

    1988-05-17

    A method for enhancing the shape selectivity and adjusting catalytic activity of a crystalline zeolite, including a highly siliceous zeolite, is disclosed. Such a method involves contacting the zeolite with an ammonium fluoride solution in the absence of an aluminum source, optionally contacting the treated zeolite with a warm aqueous solution of an ammonium salt, and then calcining the fluoride and ammonium treated zeolite to produce a more shape selective zeolite material. Such treated zeolite are useful in catalysts which promote shape selective conversion of organic compounds including, for example, hydrocarbon cracking reactions.

  9. 季铵盐壳聚糖膜对水体中十二烷基苯磺酸钠吸附的研究%Adsorption of Sodium Dodecylbenzenesulfonate from Aqueous Solution by Quaternary Chitosan Salt Membranes

    Institute of Scientific and Technical Information of China (English)

    黄晓东; 徐国钦; 娄本勇

    2012-01-01

    The quaternary chitosan salt membrane (QCSM)was prepared as an adsorbent by using chitosan as raw material, and its adsorption behavior for sodium dodecylbenzenesulfonate (SDBS)was studied. Effect factors such as solution pH, adsorption time, concentration and temperature were investigated. Results showed that pH 4.0 and shaking time 120min were the optima] conditions for adsorption of SDBS. The adsorption process followed a pseudo-second order equation and the equilibrium isotherm may be described by Langmuir model rather than the Freundlich and Tempkin model. Thermodynamic studies indicated that adsorption process was spontaneous and endothermic with an increase in entropy.%以壳聚糖为原料,制备季铵盐壳聚糖膜(QCSM)吸附剂,研究吸附剂对十二烷基苯磺酸钠(SDBS)的吸附性能,考察了溶液pH值、吸附时间、浓度和温度的影响.结果表明,吸附适宜条件的为:pH 4.0,吸附时间120 min,吸附过程可以很好地用准二级动力学方程描述,吸附等温线用Langmuir方程的拟合效果优于Freundlich和Tempkin方程.在热力学研究表中,△G0<0,△H0>0,△S0>0,表明此吸附过程是自发、吸热和熵增加的过程.

  10. Wzrost pomidorów na pożywce azotanowej lub amonowej w obecności różnych form i zróżnicowanych ilości żelaza [The development of tomato plants growing on nutrient solutions containing either nitrates or ammonium salts, in presence of various forms and doses of iron

    Directory of Open Access Journals (Sweden)

    J. Stabrowsk

    2015-05-01

    Full Text Available In all the experiments the tomato plants seemed to grow better both in aerated and nonaerated cultures in the solutions containing nitrates, than in those with ammonium salts. The best development of plants was observed in aerated cultures containing a full dose of ferric citrate. The positive effect of ferric versenate was manifested rather in the nonaerated cultures containing lower doses of this compound.

  11. Antibacterial effects of a pit and fissure sealant incorporating a quaternary ammonium monomer%季铵盐单体改性窝沟封闭剂的抗菌性能研究

    Institute of Scientific and Technical Information of China (English)

    李锋; 陈吉华; 吴丹; 李芳; 高婧; 方明

    2011-01-01

    AIM: To incorporate an antihacterial monomer, methacryloxylethyl cetyl dimethyl ammonium chloride ( DMAE-CB) , into a pit and fissure sealant, and to evaluate the antibaccerial activity of this DMAE-CB-incorporated sealant against Streptococcus mutans.METHODS : DMAE-CB was incorporated into a clinically used sealant, Helioseal.Helioseal without DMAE-CB served as a negative control.Helioseal F, containing a fluoride-releasing resin, was used as a positive control.The effects of the cured sealants on the growth and adherence of S.mutans were determined by film contact test and absorbance measurement, respectively.The influence of aging treatment on the antibacterial efficiency of the modified sealant was evaluated.Moreover, the bacterial grwrh in the eluents of three different sealants was investigated.RESULTS: The cured DMAE-CB - incorporated sealant exhibjted inhibitory effect on the growth and atiherence of S.mutans ( P < 0.05) ; whereas its eluent didnt show detectable antibacterial activity.Moreover, after aging treatment, the DMAE-CB-incorporated sealant could still inhibit the growth and adherence of S.mutans significantly ( P <0.05).CONCLUSION: The DMAE-CB-incorporated sealam after polymerization showed a contact antibacterial effect against S.mutans, which could inhibit the haccerial growth and biofilm accumulation.The antibacterial activity could be maintained after aging process.%目的:将季铵盐抗菌单体甲基丙烯酰氧乙基一正十六烷基一二甲基氯化铵(DMAE-CB)添加到窝沟封闭剂中获得改性封闭剂,评价改性封闭剂对细菌生长、黏附的影响.方法:将DMAE-CB添加到商品窝沟封闭剂Helioseal中获得DMAE-CB改性封闭剂作为实验组;未添加抗菌单体的Helioseal则作为阴性对照,具备氟释放功能的窝沟封闭剂Helioseal F作为阳性对照,采用接触抑菌实验和黏附实验评价改性封闭剂的固化表面对变异链球菌生长和黏附的影响;研究老化处理对改性材

  12. Comparison Study on Extraction of Pectin from Orange Peel by Ammonium Oxalate and Mixing-Salting Out Method%草酸铵法和混合盐析法橘皮果胶提取工艺的对比研究

    Institute of Scientific and Technical Information of China (English)

    康莹; 唐艳; 陈凯; 黄磊; 姜敏

    2013-01-01

      以汉中地产橘皮为原料,进行草酸铵法和混合盐析法橘皮果胶提取工艺条件的对比研究。实验结果表明,草酸铵法在浸提温度80℃、草酸铵浓度0.8%、料液比1∶30、浸提时间1.5h的最佳工艺条件下,果胶产率为35.6%;混合盐析法在浸提温度80℃、混合盐比12∶1、浸提时间1.5h、pH3.8的最佳工艺条件下,果胶产率为8.1%。因此,我们建议工业上用草酸铵法来提取果胶。%Applied local orange peel in Hanzhong as experimental material, the comparison extracted research of pectin from orange peel by ammonium oxalate and mixing-salting out methods was carried out. The results showed that by ammonium oxalate method, un-der the best extraction process conditions of extraction temperature 80℃, ammonium oxalate mass fraction 0.8%, the ratio of solvent to material 1∶30 and extraction time 1.5h, the pectin yield was 35.6%, while the pectin extraction rate was 8.1%by mixing-salting out method under the extraction temperature 80℃, the ratio of mixing-salt 12∶1, solvent to material ratio 1∶30, extraction time 1.5h and pH value 7. So ammonium oxalate was suggested to be used in industrial extraction of pectin from orange peel.

  13. EFFECT OF AMMONIUM NITRATE SOLUTIONS ON ...

    African Journals Online (AJOL)

    1957; Ball 1967) but the effects of these salts on marine animals is less well known. .... The first clear result of the experiments is that concentrations of ammonium ... study it is useful to know the tolerance of different stages in the life history.

  14. Insensitive Ammonium Nitrate.

    Science.gov (United States)

    is reduced by replacing the ammonium nitrate with a solid solution of potassium nitrate in form III ammonium nitrate wherein the potassium nitrate...constitutes from more than zero to less than 50 weight percent of the solid solution . (Author)

  15. 邻氯苯基卟啉-奎宁季铵盐化合物的合成及表征%The synthesis and characterization of o-chlorophenyl porphyrin-quinine quaternary ammonium salt

    Institute of Scientific and Technical Information of China (English)

    吴银素; 刘彦钦; 韩士田

    2001-01-01

    为了寻找具有手性诱导、相转移和催化为一体的三功能卟啉催化剂,探讨氯取代基的空间位置对氯苯基卟啉-奎宁季铵盐催化性能、手性不对称诱导效应的影响,合成了邻氯苯基卟啉-奎宁季铵盐化合物,其结构用UV、IR、1HNMR、MS和元素分析得到确证,并研究了其荧光光谱性质.

  16. Synthesis of softener of di-tallow amido alkyl quaternary ammonium salt%双牛脂酰乙基羟乙基甲基硫酸早酯铵柔软剂单体的合成

    Institute of Scientific and Technical Information of China (English)

    魏代军; 韩明禹

    2009-01-01

    双牛脂酰乙基羟乙基甲基硫酸甲酯铵是一种性能优良的织物柔软剂单体,广泛应用于织物柔软剂的配方中.研究了以牛油脂肪酸为原料,通过与二乙烯三胺的酰胺化合成双酰胺,双酰胺再与环氧乙烷进行乙氧基化,最后与硫酸二甲酯进行季铵化的合成过程.

  17. STUDY ON SYNTHESIS OF p-NITROANISOLE USING QUATERNARY AMMONIUM SALTS AS PHASE TRANSFER CATALYST%季铵盐相转移催化合成对硝基苯甲醚工艺研究

    Institute of Scientific and Technical Information of China (English)

    章亚东; 高晓蕾; 蒋登高; 王朝进; 王自健

    2002-01-01

    在氢氧化钠碱性介质中,以氯化苄基三乙基铵(TEBA)为相转移催化剂,由对硝基氯苯(PCNB)和甲醇(CH3OH)反应合成了对硝基苯甲醚(PNA),研究了催化剂用量、催化剂结构、碱用量等对反应的影响,确立的适宜的反应条件为:n(PCNB):n(CH3OH):n(NaOH):n(TEBA)=1:3:3:0.025~0.05,反应温度约80℃,反应时间约7~8 h.该条件下,相转移催化反应为假一级反应,反应的活化能约为74.1 kJ/mol.产品PNA收率大于95%(按对氯硝基苯计算),经气相色谱分析,产品纯度为99.7%.

  18. 用植物胶粉改性咪唑啉季铵盐型缓蚀剂%Preparation and Corrosion Inhibition Performance of Imidazoline Quaternary Ammonium Salt Modified by Plant Gelatin Powder

    Institute of Scientific and Technical Information of China (English)

    王炜; 汪晓军; 李开明; 温勇; 杜建伟

    2009-01-01

    从环保、经济和应用角度,利用天然高分子F_(691)胶粉接枝阳离子咪唑啉季铵盐,对其进行改性,合成了一种新型高效酸缓蚀剂FNP-Ⅰ.结果表明,在1 mol/L盐酸,60℃条件下,投加25 mg/L FNP-Ⅰ,缓蚀率可达到97%以上,在3 mol/L盐酸,60℃条件下,投加2 000 mg/L,缓蚀率可达到93%以上.FNP-Ⅰ具有非常好的缓蚀性能,同时具有较高的性价比,市场应用前景良好.

  19. 反应性壳聚糖季铵盐改性桑蚕丝纤维的结构与性能%Structure and properties of B.mori silk fiber treated with reactive quaternary ammonium salt of chitosan

    Institute of Scientific and Technical Information of China (English)

    张伟; 戴新兰; 周静洁; 朱刚; 徐洵; 黄颖霞; 王笃杰

    2016-01-01

    基于反应性壳聚糖季铵盐良好的水溶性和反应活性,采用异相法将壳聚糖与2,3-环氧丙基三甲基氯化铵反应,合成2-羟丙基三甲基氯化铵壳聚糖(HTCC),再将HTCC与N-羟甲基丙烯酰胺反应,合成带有反应性基团的水溶性O-甲基丙烯酰胺壳聚糖季铵盐(NMA-HTCC),并将其应用于桑蚕丝纤维的改性,测定改性前后丝纤维微观形态和聚集态结构的变化.结果表明,NMA-HTCC大分子通过与丝纤维之间的交联反应而进入到纤维内部,使改性后丝纤维内部孔隙变小,结构变得更加紧密,结晶度提高,热稳定性增强.利用NMA-HTCC改性真丝纤维作为药物载体,对芦荟提取物蒽醌具有良好的承载及控制释放效果.

  20. 端氨基超支化聚合物及其季铵盐的制备与性能%Preparation and Properties of Amino-Terminated Hyperbranched Polymers and Its Quaternary Ammonium Salt

    Institute of Scientific and Technical Information of China (English)

    张峰; 陈宇岳; 张德锁; 华琰蓉; 赵兵

    2009-01-01

    以丙烯酸甲酯和二亚乙基三胺为原料,通过缩聚反应制备了一种水溶性端氨基超支化聚合物(HBP-NH2);并以2,3-环氧丙基三甲基氯化铵(EPTAC)为改性剂,在水溶液中继续与船HBP-NH2反应,制备了端氨基超支化聚合物季铵盐(HBP-HTC).分别采用红外光谱(FT-IR)、核磁共振(1H-NMR)和凝胶色谱(GPC)分析表征了产物的结构及分子量,同时研究了HBP-NH2和HBP-HTC的溶解性能、抗菌性能、紫外吸收性能及热性能等,为其在纺织加工中的应用提供依据.结果表明,HBP-NH2和HBP-HTC具有良好的抗菌性能和紫外吸收性能,同时在H2O,二甲基亚砜(DMSO),C2H5OH和CH3OH等极性溶剂中具有优异的溶解性能.

  1. Ammonium nitrate explosion hazards

    Directory of Open Access Journals (Sweden)

    Negovanović Milanka

    2015-01-01

    Full Text Available Ammonium nitrate (AN primarily is used as a fertilizer but it is also very important compound in the production of industrial explosives. The application of ammonium nitrate in the production of industrial explosives was related with the early era of Nobel dynamite and widely increased with the appearance of blasting agents such as ANFO and Slurry, in the middle of the last Century. Throughout the world millions of tons of ammonium nitrate are produced annually and handled without incident. Although ammonium nitrate generally is used safely, accidental explosions involving AN have high impact resulting in loss of lives and destruction of property. The paper presents the basic properties of ammonium nitrate as well as hazards in handling of ammonium nitrate in order to prevent accidents. Several accidents with explosions of ammonium nitrate resulted in catastrophic consequences are listed in the paper as examples of non-compliance with prescribed procedures.

  2. Susceptibility to disinfectants in antimicrobial-resistant and -susceptible isolates of Escherichia coli, Enterococcus faecalis and Enterococcus faecium from poultry-ESBL/AmpC-phenotype of E. coli is not associated with resistance to a quaternary ammonium compound, DDAC.

    Science.gov (United States)

    Wieland, N; Boss, J; Lettmann, S; Fritz, B; Schwaiger, K; Bauer, J; Hölzel, C S

    2017-06-01

    The spread of bacteria that are simultaneously resistant to disinfectants and antimicrobials would constitute an unsettling scenario. In order to explore an association between antimicrobial resistance and reduced susceptibility to biocides/microbicides (disinfectants) in agriculture, we investigated Escherichia coli (n = 438) and enterococci (n = 120) isolated from six different flocks of the same poultry farm with known history of antimicrobial treatment. Susceptibility to disinfectants (formic acid and a quaternary ammonium compound (QAC), didecyldimethylammoniumchloride-DDAC) was assessed by macrodilution according to guidelines of the German Veterinary Society. Escherichia coli, Enterococcus faecalis and Enterococcus faecium were screened (i) for reduced biocide susceptibility and (ii) for an association of biocide susceptibility and antimicrobial resistance including the production of extended-spectrum beta-lactamases (ESBL) and the hyperproduction of AmpC-type beta-lactamases. DDAC inhibited ESBL/AmpC(hyper)-producing E. coli (n = 53) from poultry at similar or slightly lower inhibitory concentrations, compared with non-ESBL/AmpC strains (median MIC = 0·36 vs 1·44 mg l(-1) ). In contrast, DDAC-MICs were positively correlated with several other antibiotic MICs (e.g. piperacillin and sulphamethoxazole + trimethoprim in E. coli, chloramphenicol in E. faecalis) and increased DDAC-MICs were statistically linked to high-level aminoglycoside resistance in enterococci (streptomycin high level). DDAC-MICs did not correlate with the presence of the integron marker qacEDelta1. This study provides indication that residual disinfectant might be able to select antimicrobial-resistant enterococci, but not ESBL-/AmpC (hyper)producing E. coli from poultry. While ESBL-/AmpC-E. coli were inhibited at disinfectant concentrations comparable to or lower than wildtype values, low concentrations of QACs might be able to select other antimicrobial-resistant E

  3. O-季铵化-N-(4-十二烷氧基)壳聚糖苯甲醛席夫碱的制备及胶束pH响应性%Preparation and micelle pH response ofO-quaternary ammonium-N-(4-dodecyloxy) chitosan benzaldehyde Schiff’s bass

    Institute of Scientific and Technical Information of China (English)

    林意华; 李明春; 辛梅华; 陈燕燕

    2015-01-01

    制备双亲性的O-季铵化-N-(4-十二烷氧基)壳聚糖苯甲醛席夫碱(QA-CS-DBA),采用FTIR、1H NMR及元素分析对产物进行表征。通过超声法制备QA-CS-DBA载酮洛芬胶束,考察胶束的临界胶束浓度、粒径、Zeta电位、载药量和包封率,并对胶束在不同 pH 值条件下的药物释放行为及 Zeta 电位变化进行研究。结果表明, QA-CS-DBA能将酮洛芬包载于胶束疏水内核,载药量为39.37%,包封率为46.04%,载药胶束粒径为341nm, Zeta电位为30.8mV。胶束Zeta电位及载药胶束的药物释放行为具有pH响应性。%AmphiphilicO-quaternary ammonium-N-(4-dodecyloxy) chitosan benzaldehyde Schiff’s base (QA-CS- DBA) was prepared. FTIR,1H NMR and EA were used to confirm its structure. The micelle of QA-CS-DBA carrying ketoprofen was made by ultrasounding. The CMC,size,Zeta potential,drug loading capacity and encapsulation efficiency were studied,especially the behavior of drug release and the change of Zeta potential in different PBS buffer solution with different pH. The result shows that QA-CS-DBA could form stable drug loading micelles carrying ketoprofen with the size about 341nm. The drug loading capacity and the encapsulation efficiency are 39.37% and 46.04% respectively and the Zeta potential is 30.8mV. With pH changing between 7.40 and 6.50,the micelle shows different Zeta potentials and different behaviors in drug release.

  4. A NEW METHOD FOR QUANTIFYING THE DEGREE OF SUBSTITUTION OF AMPHOTERIC STARCH WITH CARBOXYLIC GROUP AND QUATERNARY AMMONIUM GROUP IN PAPERMAKING:NEW COLLOID TITRATION METHOD%造纸用季铵盐羧酸型两性淀粉的阴、阳离子取代度的新测量方法:新胶体滴定法

    Institute of Scientific and Technical Information of China (English)

    罗明辉; 陆恩锡

    2008-01-01

    A new colloid titration method for analyzing the degree of substitute (DS) of amphoteric starch with carboxylic and quaternary ammonium groups is first developed in this work. The cationic or anionic desires will be measured while measuring the oxidized starches of known carboxylic DS or cationic starches of known cationic DS by back titration. The amphoteric starch′s DS will be reached by interpolation method while two calibration equations of the DSes and desires are obtained through the polynomial regression based on the analyzed data. The cationic and anionic DS in the traditional method are 0.032 and 0.022, respectively. Their DS in the New Colloid Titration are 0.033 and 0.018, respectively. In comparison with the traditional method, the new method avoids the variations of the cationic and anionic groups during the analyzing. Thus, when the starch′s complex mechanism is analyzed, the results obtained by the new method are more accurate and reflect the real degree of substitution of the amphoteric starch.%首次提出了用胶体滴定法测量季铵盐羧酸型两性淀粉的阴、阳离子取代度.通过测量已知羧基取代度的氧化淀粉或已知季铵盐取代度的阳离子淀粉的阳性需求量或阴性需求量,对其做出取代度与需求量的校正工作方程,使用内插法分别得出了该两性淀粉的阳离子取代度和阴离子取代度.在用传统测量方法测量该两性淀粉的阴、阳离子取代度分别为0.022和0.032的情况下,使用新胶体滴定法测量的结果分别为0.018和0.033.对比两种方法,使用新胶体滴定法避免了阴、阳离子基团在测量过程中的变化.通过机理分析,使用胶体滴定法测量该淀粉更准确、更符合实际情况.

  5. Chloride Ion Conductivity in a Plasticized Quaternary Ammonium Polymer.

    Science.gov (United States)

    1983-11-22

    C., 1980; pp. 67-76. 12. Stainer , M.; Hardy, L. C.; Whitmore, D. H.; Shriver, D. F. J. Electrochem. Soc., in press. 13. Arai, K.; Eisenberg, A. J...Dr. G. Goodman Department of Chemistry Johnson Controls California Institute of Technology 5757 North Green Bay Avenue Pasadena, California 91125

  6. Synthesis of Polymer-Bonded Quaternary Ammonium Type Metal Porphyrins

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The reaction of pyrrole with 4-hydroxybenzaldehyde and 4-pyridinecarboxaldehyde afforded new porphyrin ligand 1.Treatment of 1 with copper(Ⅱ) acetate, cobalt (Ⅱ) acetate gave complexes 2-3 respectively.2 and 3 reacted with Merrifield's peptide resin produced 4 and 5.Complexes 4 and 5 reacted with methyl iodide respectively gave 6-7.The new compounds 1-7 have been identified by 1H NMR, IR, MS and UV-visible spectra, elemental analysis and AES.

  7. Quaternary ammonium borohydride adsorption in mesoporous silicate MCM-48

    Energy Technology Data Exchange (ETDEWEB)

    Wolverton, Michael J [Los Alamos National Laboratory; Daemen, Luke L [Los Alamos National Laboratory; Hartl, Monika A [Los Alamos National Laboratory

    2010-01-01

    Inorganic borohydrides have a high gravimetric hydrogen density but release H2 only under energetically unfavorable conditions. Surface chemistry may help in lowering thermodynamic barriers, but inclusion of inorganic borohydrides in porous silica materials has proved hitherto difficult or impossible. We show that borohydrides with a large organic cation are readily adsorbed inside mesoporous silicates, particularly after surface treatment. Thermal analysis reveals that the decomposition thermodynamics of tetraalkylammonium borohydrides are substantially affected by inclusion in MCM-48. Inelastic neutron scattering (INS) data show that the compounds adsorb on the silica surface. Evidence of pore loading is supplemented by DSC/TGA, XRD, FTIR, and BET isotherm measurements. Mass spectrometry shows significant hydrogen release at lower temperature from adsorbed borohydrides in comparison with the bulk borohydrides. INS data measured for partially decomposed samples indicates that the decomposition of the cation and anion is likely simultaneous. Additionally, these data confirm the formation of Si-H bonds on the silica surface upon decomposition of adsorbed tetramethylammonium borohydride.

  8. Bacterial resistance to Quaternary Ammonium Compounds (QAC) disinfectants.

    Science.gov (United States)

    Bragg, Robert; Jansen, Arina; Coetzee, Marisa; van der Westhuizen, Wouter; Boucher, Charlotte

    2014-01-01

    Control of bacterial diseases has, for many years, been dependent on the use of antibiotics. Due to the high levels of efficacy of antibiotics in the past other disease control options have, to a large extent, been neglected. Mankind is now facing an increasing problem with antibiotic resistance. In an effort to retain some antibiotics for human use, there are moves afoot to limit or even ban the use of antibiotics in animal production. The use of antibiotics as growth promoters have been banned in the European Union and the USA. The potential ban on the use of antibiotics to treat diseases in production animals creates a dilemma for man-suffer significant problem with bacterial infection or suffer from a severe shortage of food! There are other options for the control of bacterial diseases. These include vaccine development, bacteriophage therapy, and improved biosecurity. Vaccine development against bacterial pathogens, particularly opportunistic pathogens, is often very challenging, as in many cases the molecular basis of the virulence is not always clearly understood. This is particularly true for Escherichia coli. Biosecurity (disinfection) has been a highly neglected area in disease control. With the ever-increasing problems with antibiotic resistance-the focus should return to improvements in biosecurity. As with antibiotics, bacteria also have mechanisms for resistance to disinfectants. To ensure that we do not replace one set of problems (increasing antibiotic resistance) with another (increasing resistance to disinfectants) we need to fully understand the modes of action of disinfectants and how the bacteria develop resistance to these disinfectants. Molecular studies have been undertaken to relate the presence of QAC resistance genes in bacteria to their levels of sensitivity to different generations of QAC-based products. The mode of action of QAC on bacteria has been studied using NanoSAM technology, where it was revealed that the QAC causes disruption of the bacterial cell wall and leaking of the cytoplasm out of the cells. Our main focus is on the control of bacterial and viral diseases in the poultry industry in a post-antibiotic era, but the principles remain similar for disease control in any veterinary field as well as in human medicine.

  9. Microbial community degradation of widely used quaternary ammonium disinfectants.

    Science.gov (United States)

    Oh, Seungdae; Kurt, Zohre; Tsementzi, Despina; Weigand, Michael R; Kim, Minjae; Hatt, Janet K; Tandukar, Madan; Pavlostathis, Spyros G; Spain, Jim C; Konstantinidis, Konstantinos T

    2014-10-01

    Benzalkonium chlorides (BACs) are disinfectants widely used in a variety of clinical and environmental settings to prevent microbial infections, and they are frequently detected in nontarget environments, such as aquatic and engineered biological systems, even at toxic levels. Therefore, microbial degradation of BACs has important ramifications for alleviating disinfectant toxicity in nontarget environments as well as compromising disinfectant efficacy in target environments. However, how natural microbial communities respond to BAC exposure and what genes underlie BAC biodegradation remain elusive. Our previous metagenomic analysis of a river sediment microbial community revealed that BAC exposure selected for a low-diversity community, dominated by several members of the Pseudomonas genus that quickly degraded BACs. To elucidate the genetic determinants of BAC degradation, we conducted time-series metatranscriptomic analysis of this microbial community during a complete feeding cycle with BACs as the sole carbon and energy source under aerobic conditions. Metatranscriptomic profiles revealed a candidate gene for BAC dealkylation, the first step in BAC biodegradation that results in a product 500 times less toxic. Subsequent biochemical assays and isolate characterization verified that the putative amine oxidase gene product was functionally capable of initiating BAC degradation. Our analysis also revealed cooperative interactions among community members to alleviate BAC toxicity, such as the further degradation of BAC dealkylation by-products by organisms not encoding amine oxidase. Collectively, our results advance the understanding of BAC aerobic biodegradation and provide genetic biomarkers to assess the critical first step of this process in nontarget environments.

  10. Clinoptilolite-based mixed matrix membranes for the selective recovery of potassium and ammonium

    NARCIS (Netherlands)

    Casadella, A.; Kuntke, P.; Schaetzle, O.; Loos, K.

    2016-01-01

    . A clinoptilolite-based mixed matrix membrane (MMM) was developed and studied for the selective recovery of ammonium and potassium. Adsorption of sodium (Na+), potassium (K+) and ammonium (NH4+) was investigated with single salt and equimolar salt solution under static and dynamic conditions. Furth

  11. Clinoptilolite-based mixed matrix membranes for the selective recovery of potassium and ammonium

    NARCIS (Netherlands)

    Casadella, A.; Kuntke, P.; Schaetzle, O.; Loos, K.

    2016-01-01

    . A clinoptilolite-based mixed matrix membrane (MMM) was developed and studied for the selective recovery of ammonium and potassium. Adsorption of sodium (Na+), potassium (K+) and ammonium (NH4+) was investigated with single salt and equimolar salt solution under static and dynamic conditions.

  12. Simultaneous Extraction and Determination of Three Quaternary Ammonium Compouds in Soil by Ultrasonic Exaction and Gas Chromatography-Mass Spectrometry%超声萃取-气相色谱/质谱法同时测定土壤中3种季胺盐化合物

    Institute of Scientific and Technical Information of China (English)

    向垒; 郑美洁; 王雄科; 李彦文; 莫测辉; 蔡全英; 黄献培; 吴小莲; 赵海明

    2014-01-01

    An analytical method was developed for the simultaneous extraction and determination of three quaternary ammonium compouds ( QACs) in soil samples using ultrasonic extraction and gas chromatography-mass spectrometry( GC-MS) . The qualitative and quantitative analysis of the three analytes dodecyltrimethyl ammonium chloride ( DTAC) , cetyltrimethyl ammonium bromide ( CTAB) and didodecyldimethyl ammonium chloride ( DDAC) were conducted by application of EI mass spectra and selected ion monioring ( SIM ) . Characteristic ions of the QACs were m/z 58 ( DTAC and CTAB) and m/z 212 ( DDAC) . To achieve optimum extraction efficiency, several impact factors including types of extractants, pH of extraction, concentration of linear alkylbenzene sulfonates ( LAS) , extraction times and content of purification column were investigated. Methanol with pH 3. 5 and 40 μg/L LAS solution were selected as extractant. Soil sample was extracted by treated methanol each 10 mL for 20 min every time. Extract of the soil sample was purified by neutral alumina column with 4 cm in length and 1cm in diameter, and then was determineted by GC-MS. Good linear relationships of all the three QACs were obtained in the range of 0. 02-2. 0 mg/L. The limits of determination (LOD, S/N=3) was 1. 2-4. 5 μg/kg. The method was used to analyse real soil samples ( paddy soil, lateritic red soil, and ore tailings) collected from a mining district in south China. Results of determination exhibited the concerntrations of the three analytes in real soil samples ranged from 0 . 24 mg/kg to 0. 41 mg/kg, and their recoveries ranged from 76% to 113% with relative standard deviations ( RSD) of 1. 1%-12. 9% in three different spiked concentrations of 0. 2, 0. 5 and 1. 0 mg/kg.%建立了超声萃取-气相色谱/质谱法同时测定土壤中3种典型季胺盐化合物十二烷基三甲基氯化胺(DTAC)、十六烷基三甲基溴化胺(CTAB)、双十二烷基二甲基氯化胺(DDAC)的分析

  13. Elevated ammonium levels

    DEFF Research Database (Denmark)

    Søgaard, Rikke; Novak, Ivana; MacAulay, Nanna

    2012-01-01

    ]glutamate uptake and glutamate transport currents but had no effect on EAAT2. The maximal EAAT3-mediated glutamate transport current was increased but the apparent affinities for glutamate and Na(+) were unaltered. Ammonium did not affect EAAT3-mediated transient currents, indicating that EAAT3 surface expression...... was not enhanced. The ammonium-induced stimulation of EAAT3 increased with increasing extracellular pH, suggesting that the gaseous form NH(3) mediates the effect. An ammonium-induced intracellular alkalinization was excluded as the cause of the enhanced EAAT3 activity because 1) ammonium acidified the oocyte...... cytoplasm, 2) intracellular pH buffering with MOPS did not reduce the stimulation, and 3) ammonium enhanced pH-independent cysteine transport. Our data suggest that the ammonium-elicited uptake stimulation is not caused by intracellular alkalinization or changes in the concentrations of cotransported ions...

  14. QUATERNARY GEOLOGY & GEOMORPHOLOGY

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20112526Bai Daoyuan (Hunan Institute of Geology Survey,Changsha 410011,China); Liu Bo Quaternary Tectonic-Sedimentary Characteristics and Environmental Evolution of Linli Sag,Dongting Basin (Journal of

  15. QUATERNARY GEOLOGY & GEOMORPHOLOGY

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20111129 Bai Daoyuan(Hunan Institute of Geological Survey,Changsha 410011,China);Li Chang’an Quaternary Tectonic-Sedimentary Characteristics and Environmental Evolution of Anxiang Sag in Dongting Basin and Its West Periphery(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,32(2),2010,p.120-129,6 illus.,1 table,48 refs.)Key words:Quaternary,sedimentary environment,structural evolution,Dongtinghu Basin Detailed geologic mapping and bore data was conducted to study on the Quaternary tectonic and sedimentary characteristics and environmental evolution of Anxiang Sag and its west periphery of Dongting Basin,which provided new materials for Quaternary geology of Jianghan-Dongting Basin.The sag trends north-south direction and is surrounded by normal faults.The thickness of Quaternary deposits in the sag is commonly 100~220 m with maximun thickness of 300 m,and from lower to upper,the Quaternary strata is composed of Early Pleistocene Huatian Formation and Miluo Formation,Middle Pleistocene Dongtinghu Formation

  16. Effect of quaternary ammonium methacrylates incorporation into a dental adhesive on the resistance of enzymatic degradation of resin-dentine interfaces%季铵盐单体改性粘接剂对牙本质粘接界面耐酶解能力的影响

    Institute of Scientific and Technical Information of China (English)

    刘宁; 李芳; 陈宇江; 窦祈; 沈丽娟; 陈吉华

    2013-01-01

    目的 研究季铵盐单体改性粘接剂对牙本质粘接界面耐酶解性能的影响,探索提高牙本质粘接耐久性的新方法.方法 30颗无龋人第三磨牙通过随机数字表法随机分为3组(每组10颗):季铵盐单体[2-甲基丙烯酰氧乙基-正十二烷基-甲基溴化铵(2-methacryloxylethyl dodecylmethyl ammonium bromide,MAE-DB)]改性的粘接剂(AdperTM Single Bond 2)组(简称MAE-DB组)、氯己定组和阴性对照组(AdperTM Single Bond 2粘接剂).全酸蚀粘接技术制作标准牙本质粘接试件,37℃水浴浸泡24 h后,制成微拉伸试件,浸泡于酶解液中0、24和120 h(每组每个时间点30个试件).检测各组试件粘接强度、断裂模式和纳米渗漏情况.结果 未经酶解处理的各组试件粘接强度差异无统计学意义(P>0.05).酶解处理24和120 h后,MAE-DB组的粘接强度分别为(31.13 ±8.77)和(24.14±6.64) MPa,分别显著高于阴性对照组相应时间点[(25.63±6.90)和(15.22±6.57) MPa](P<0.05).酶解处理后阴性对照组的断裂多发生于混合层底部,而氯己定组和MAE-DB组断裂多发生于混合层顶部.酶解处理前各组均可见少量的银离子沉积于混合层底部.酶解处理120 h后,扫描电镜显示,氯己定组和MAE-DB组混合层底部的纳米渗漏银离子比阴性对照组少,纳米渗漏分级计数差异有统计学意义(P<0.05).结论 MAE-DB改性牙本质粘接剂可有效提高牙本质粘接界面的耐酶解能力.%Objective To evaluate the effect of quaternary ammonium methacrylates incorporation into a dental adhesive on the resistance of enzymatic degradation of resin-dentine interfaces.Methods Thirty caries-free extracted human third molars were randomly divided into three groups (n =10):2-methacryloxylethyl dodecylmethyl ammonium bromide (MAE-DB) incorporated adhesive served as the experimental group,pre-treatment with chlorhexidine (CHX) served as a positive control,AdperTM Single Bond 2 served as a negative control

  17. 季铵盐阳离子表面活性剂对普通小球藻和斜生栅藻的急性毒性%Acute Toxicity of Quaternary Ammonium Cationic Surfactants to Chlorella vulgaris and Scenedesmus obliquus

    Institute of Scientific and Technical Information of China (English)

    喻方琴; 葛飞; 朱门君; 梁志杰; 刘燕

    2012-01-01

    Chlorella vulgaris and Scenedesmus obliquus, two green freshwater alga in environment, have been widely used to evaluate the impacts of xenobiotics duo to their sensitivity to contaminants. In this study, we investigated the acute toxicity of quaternary ammonium cationic surfactants(QACS) with different length of alkyl chain(CL=8~18) to C. vulgaris and S. obliquus. The results indicated that the 96 h-EC50 value of thirteen kinds of QACS on C. vulgaris and S. obliquus were 0.108~9.472 mg·L‐1 and 0.085~12.188 mg·L‐1, respectively. Furthermore, the acute toxicity of QACS with the same substituent group on the two species of algae gradually increased with the increasing of CL. However, the different substituent groups had little effect on the acute toxicity of QACS with the same CL to the two green algae. The relationship between acute toxicity[lg( I/EC50)] and octanol-water partition coefficients(lgKow), CL could be better fitted by parabola model than linear equation, and the fitting trends were same for the two green algae. The parabola equations for C. vulgaris and S. obliquus were lg( l/EC50)=-0.106 lgK2ow+0.746 lgKow,-0.830(R2=0.944), lg( 1/EC50)=-0.034 CL2+1.051 CL-7.725(R2=0.945) and lg( l/EC50=-0.l 19 lgK2ow +0.830 lgAow-0.812(R2=0.941), lg( l/EC50)=-0.039 CL2+1.218 CL-8.772(R2=0.945), respectively, which could provide references for the prediction of acute toxicity for similar compounds to freshwater algae.%以普通小球藻(Chlorella vulgaris)和斜生栅藻(Scenedesmus obliquus)为受试生物,采用批量培养方法研究了13种季铵盐阳离子表面活性剂(QACS,烷基链长度CL=8~18)对两种淡水藻的急性毒性.结果表明,13种QACS对普通小球藻和斜生栅藻的96h-EC50分别在0.108~9.472 mg· L-1和0.085~12.188 mg·L-1之间;且随着烷基链长度CL的增加,取代基相同的QACS对两种淡水藻的急性毒性逐渐增大.抛物线模型较线性方程能更好地拟合QACS的急性毒性参数lg(1/EC50)与辛醇/

  18. Discovery of a novel series of phenyl pyrazole inner salts based on fipronil as potential dual-target insecticides.

    Science.gov (United States)

    Jiang, Dingxin; Zheng, Xiaohua; Shao, Guang; Ling, Zhang; Xu, Hanhong

    2014-04-23

    A series of novel phenyl pyrazole inner salt derivatives based on fipronil were designed and synthesized in the search for dual-target insecticides. These compounds were designed to target two families of nicotinic acetylcholine receptors and γ-aminobutyric acid receptors. The insecticidal activities of the new compounds against diamondback moth (Plutella xylostella) were evaluated. The results of bioassays indicated that most of the inner salts showed moderate to high activities, of which the phenyl pyrazole inner salts containing quinoline had excellent biological activity. Previous structure-activity relationship studies revealed that a suitable structure of the quaternary ammonium salts was critical for the bioactivity of phenyl pyrazole inner salts, which contribute to exposing the cationic nitrogen to bind to the receptor (for instance, nicotinic acetylcholine receptors) and possibly interact with the receptor via hydrogen bonding and cooperative π-π interaction. The present work demonstrates that the insecticidal potency of phenyl pyrazole inner salts holds promise for the development new dual-target phenyl pyrazole insecticides.

  19. Electrochromic Salts, Solutions, and Devices

    Energy Technology Data Exchange (ETDEWEB)

    Burrell, Anthony K. (Los Alamos, NM); Warner, Benjamin P. (Los Alamos, NM); McClesky, T. Mark (Los Alamos, NM)

    2008-11-11

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

  20. Electrochromic Salts, Solutions, and Devices

    Energy Technology Data Exchange (ETDEWEB)

    Burrell, Anthony K. (Los Alamos, NM); Warner, Benjamin P. (Los Alamos, NM); McClesky, T. Mark (Los Alamos, NM)

    2008-10-14

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

  1. Electrochromic salts, solutions, and devices

    Energy Technology Data Exchange (ETDEWEB)

    Burrell, Anthony K. (Los Alamos, NM); Warner, Benjamin P. (Los Alamos, NM); McClesky,7,064,212 T. Mark (Los Alamos, NM)

    2006-06-20

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

  2. Synthesis of guanidine from ammonium thiocyanate in solid state

    OpenAIRE

    Zaia Dimas A. M.; Santana Henrique de; Toppan Rodrigo; Zaia Cássia T. B. V.

    2004-01-01

    Guanidine is an important substance for modern living beings as well as for the prebiotic chemistry. We studied the reaction between ammonium and thiocyanate species in solid state with different substances (river sand, kaolin, transition metals, salts of seawater) and temperatures (80, 120 and 150 ºC). The recoveries of thiocyanate and ammonium in the samples with river sand or kaolin at 150 ºC were statistically different (p

  3. Ammonium Lactate Topical

    Science.gov (United States)

    ... are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while using ammonium lactate, call your doctor.plan to avoid unnecessary or prolonged exposure to natural or artificial sunlight to the affected skin area and to ...

  4. Size-dependent reactions of ammonium bisulfate clusters with dimethylamine.

    Science.gov (United States)

    Bzdek, Bryan R; Ridge, Douglas P; Johnston, Murray V

    2010-11-04

    The reaction kinetics of ammonium bisulfate clusters with dimethylamine (DMA) gas were investigated using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). Clusters ranged in size from 1 to 10 bisulfate ions. Although displacement of the first several ammonium ions by DMA occurred with near unit efficiency, displacement of the final ammonium ion was cluster size dependent. For small clusters, all ammonium ions are exposed to incoming DMA molecules, allowing for facile exchange ("surface" exchange). However, with increasing cluster size, an ammonium ion can be trapped in an inaccessible region of the cluster ("core" exchange), thereby rendering exchange difficult. DMA was also observed to add onto existing dimethylaminium bisulfate clusters above a critical size, whereas ammonia did not add onto ammonium bisulfate clusters. The results suggest that as the cluster size increases, di-dimethylaminium sulfate formation becomes more favorable. The results of this study give further evidence to suggest that ambient sub-3 nm diameter particles are likely to contain aminium salts rather than ammonium salts.

  5. Second Quaternary dating workshop

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-11-01

    The second Quaternary dating methods workshop was held at Lucas Heights and sponsored by ANSTO and AINSE. Topics covered include, isotope and thermoluminescence dating, usage of accelerator and thermal ionisation mass spectrometry in environmental studies emphasizing on the methodologies used and sample preparation

  6. Construction techniques for adiabatic demagnetization refrigerators using ferric ammonium alum

    Science.gov (United States)

    Wilson, Grant W.; Timbie, Peter T.

    1999-07-01

    We describe techniques used to fabricate the cold stage of an adiabatic demagnetization refrigerator that uses the paramagnetic salt ferric ammonium alum. We discuss the design of a leak-tight housing for the salt as well as a technique for growing ferric ammonium alum crystals that results in a housing filled with >98% refrigerant. These techniques have proven to be reliable in creating robust single-stage refrigerators. Similar techniques can be used for the second stage of a dual-stage adiabatic demagnetization refrigerator.

  7. Performance and mechanisms of salt-torrent ANAMMOX process

    Institute of Scientific and Technical Information of China (English)

    WU Guo-dong

    2016-01-01

    [Abstract]Wide application of seawater made the biological denitrification in the saline wastewater treatment become a difficult problem, expounds the salt effect on anaerobic ammonium oxidation,summarizes the salt resistance of anaerobic ammonia oxidation microorganism acclimation, points out that the two kinds of mechanism of salt stress on the denitrification microbes,and to make a optimization strategy on salt stress.

  8. Synthesis of guanidine from ammonium thiocyanate in solid state

    Directory of Open Access Journals (Sweden)

    Zaia Dimas A. M.

    2004-01-01

    Full Text Available Guanidine is an important substance for modern living beings as well as for the prebiotic chemistry. We studied the reaction between ammonium and thiocyanate species in solid state with different substances (river sand, kaolin, transition metals, salts of seawater and temperatures (80, 120 and 150 ºC. The recoveries of thiocyanate and ammonium in the samples with river sand or kaolin at 150 ºC were statistically different (p<0.05 from the recoveries of thiocyanate and ammonium in the sample without them. The decomposition of ammonium thiocyanate in the samples river sand or kaolin at 150 ºC was about 40%. Kaolin showed to have more effect on the synthesis guanidine than river sand, because, the concentrations of guanidine in the samples with kaolin were always bigger than in the samples with river sand. The decomposition of ammonium thiocyanate in the samples with transition metals plus river sand at 120 ºC was about 30%. The salts of seawater or transition metals plus ammonium thiocyanate plus river sand (120 ºC showed to increase the concentration of thiourea (seawater: 538%; transition metals: 357% or guanidine (seawater: 393%, transition metals: 806% when they were compared to the samples without them. When the results obtained with sample of ammonium thiocyanate were compared to the samples of ammonium thiocyanate (at 120 ºC plus salts of seawater or transition metals also an increased on the production of thiourea (168% and guanidine (268% was obtained, respectively. The yield for the synthesis of guanidine showed in this paper is better than that obtained by other authors. Experiments showed that iron (III is involving in the formation of the yellow compound and Raman spectra showed this compound could be sulphur.

  9. Sensibilidade e resistência de amostras de Salmonella Typhimurium isoladas de suínos abatidos no Rio Grande do Sul/Brasil frente aos desinfetantes químicos quaternário de amônio e iodofor Sensitivity and resistance of samples of Salmonella Typhimurium isolated in slaughter swines in the state Rio Grande do Sul/Brazil, front to disinfectants quaternary ammonium and iodophor

    Directory of Open Access Journals (Sweden)

    Luciane Martins Borowsky

    2006-10-01

    of 96 Salmonella Typhimurium strains isolated from slaughter pigs in the state of Rio Grande do Sul, Brazil. The isolates were tested against quaternary ammonium and iodophor, which represent two commercial disinfectants commonly used in animal production. The tested disinfectants were used in the concentration recommended by the fabricant and in a sub-concentration in order to simulate a possible field situation. Dilution suspension tests were conducted, observing the inactivation of each S.Typhimurium isolate after 5, 15, 30 and 60 minutes of contact with each compound. All tested isolates were inactivated by the quaternary ammonium compound in both concentrations. Four isolates revealed resistant to iodophor in the recommended concentration and 59 isolates when a sub-concentration was tested. The testing of resistance against disinfectants in microorganisms present on farm and in food processing plants might be an important step on monitoring the effectiveness of adopted disinfections protocols.

  10. Chiral ammonium betaine-catalyzed asymmetric Mannich-type reaction of oxindoles

    Directory of Open Access Journals (Sweden)

    Masahiro Torii

    2016-09-01

    Full Text Available A highly diastereo- and enantioselective Mannich-type reaction of 3-aryloxindoles with N-Boc aldimines was achieved under the catalysis of axially chiral ammonium betaines. This catalytic method provides a new tool for the construction of consecutive quaternary and tertiary stereogenic carbon centers on biologically intriguing molecular frameworks with high fidelity.

  11. QUATERNARY GEOLOGY & GEOMORPHOLOGY

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    <正>20050939 An Chengbang (Key Lab. of Western Chinese Environment System, Ministry of Education, Lanzhou University, Lanzhou, Gansu 730000, China); Feng Zhaodong Humid Climate During 9-3. 8 KaBP in the Western Part of Chinese Loess Plateau (Marine Geology & Quaternary Geology, ISSN0256-1492, CN37-1117/P, 24 (3), 2004, p. 111-116, 3 illus. , 1 table, 40 refs. , with English abstract)

  12. Partitioning the Quaternary

    Science.gov (United States)

    Gibbard, Philip L.; Lewin, John

    2016-11-01

    We review the historical purposes and procedures for stratigraphical division and naming within the Quaternary, and summarize the current requirements for formal partitioning through the International Commission on Stratigraphy (ICS). A raft of new data and evidence has impacted traditional approaches: quasi-continuous records from ocean sediments and ice cores, new numerical dating techniques, and alternative macro-models, such as those provided through Sequence Stratigraphy and Earth-System Science. The practical usefulness of division remains, but there is now greater appreciation of complex Quaternary detail and the modelling of time continua, the latter also extending into the future. There are problems both of commission (what is done, but could be done better) and of omission (what gets left out) in partitioning the Quaternary. These include the challenge set by the use of unconformities as stage boundaries, how to deal with multiphase records in ocean and terrestrial sediments, what happened at the 'Early-Mid- (Middle) Pleistocene Transition', dealing with trends that cross phase boundaries, and the current controversial focus on how to subdivide the Holocene and formally define an 'Anthropocene'.

  13. Effects of Calcium Lignosulfonate and Silicic Acid on Ammonium Nitrate Degradation

    Directory of Open Access Journals (Sweden)

    Ahmet Ozan Gezerman

    2014-01-01

    Full Text Available Ammonium nitrate salts are the most commonly used nitrogenous fertilizers in industry. However, storage of ammonium nitrate is problematic, since its initial properties can decline because of environmental factors, leading to large economic losses. In this study, in order to prevent the caking and degradation of ammonium nitrate, an alternative composition with additional calcium lignosulfonate and silicic acid was studied. The resulting fertilizer was analyzed by screening analysis, ion chromatography, and electron microscopy methods.

  14. Novel carbohydrate-based chiral ammonium ionic liquids derived from isomannide

    DEFF Research Database (Denmark)

    Kumar, Vineet; Pei, Cao; Olsen, Carl E.

    2008-01-01

    This report describes the synthesis and characterization of novel carbohydrate-based chiral ammonium ionic liquids using isomannide as a biorenewable substrate. The diastereomeric interactions of these chiral ammonium ionic liquids with racemic Mosher's acid salt have been studied using NMR, whic...

  15. Cyanines Bearing Quaternary Azaaromatic Moieties

    OpenAIRE

    Sbliwa, Wanda; Matusiak, Grazyna; Bachowska, Barbara

    2006-01-01

    Selected cyanines bearing quaternary azaaromatic moieties are presented, showing their monomers, dimers and polymers, as well as their possible applications. Cyanines having NLO properties are also briefly described.

  16. Quaternary Organic Amines Inhibit Na,K Pump Current in a Voltage-dependent Manner

    OpenAIRE

    2004-01-01

    The effects of organic quaternary amines, tetraethylammonium (TEA) chloride and benzyltriethylammonium (BTEA) chloride, on Na,K pump current were examined in rat cardiac myocytes superfused in extracellular Na+-free solutions and whole-cell voltage-clamped with patch electrodes containing a high Na+-salt solution. Extracellular application of these quaternary amines competitively inhibited extracellular K+ (K+ o) activation of Na,K pump current; however, the concentration for half maximal inh...

  17. Novel Ammonium Metal Borohydrides

    DEFF Research Database (Denmark)

    Grinderslev, Jakob; Jepsen, Lars Haahr; Cerny, Radovan

    , it cannot store hydrogen reversibly. Recently, the first ammonium metal borohydride, NH4Ca(BH4)3 was published, which may be considered as substitution of K+ by NH4+ in KCa(BH4)3, due to the similar sizes of NH4+ and K+[1]. This compound successfully stabilizes NH4BH4. In the present work, a series of novel......, and the crystal structures and thermal decompositions are investigated. Mixtures of NH4BH4 - NaBH4 do not react, while solid solutions, K1-x(NH4)xBH4, are formed for NH4BH4 - KBH4. For the other composites, novel ammonium metal borohydrides are formed. Several of these structures have been solved from high...

  18. Magnetism of quaternary sediments

    Science.gov (United States)

    Heller, Friedrich

    Magnetism of Quaternary sediments was the topic of a well-attended symposium held during the 13th INQUA (International Union of Quaternary Research) congress in Beijing, China, August 2-9. More than 40 papers were delivered by scientists from Belgium, England, France, Germany, Japan, New Zealand, Sweden, Switzerland, Taiwan, the United States, the Soviet Union, Yugoslavia, and other countries. The host country contributed to a productive session that was part of the first large scientific meeting to take place in Beijing after the June 4, 1989, upheaval.Nearly half of the studies focused on paleomagnetic and rock magnetic properties of loess in Alaska, Central Asia, China, and New Zealand. Magnetostratigraphic polarity dating was done at some sections in the western (Shaw et al.) and central Chinese loess plateau (Bai and Hus; Wang and Evans; Yue). The interpretation of the polarity pattern found in the western loess plateau still is not unambiguous. In the central part, certain polarity boundaries, such as the Brunhes/Matuyama (B/M) boundary, are found in slightly different stratigraphic positions (Hus et al.; Yue). In deep-sea sediments the lock-in depth of natural remanent magnetization (NRM) at the B/M boundary seems to be a linear function of sedimentation rate (de Menocal et al.). Although the magnetization process in the Chinese loess is not well understood, detailed records of polarity transitions have been reported for the B/M and the Jaramillo R→N transition (Ma et al.; Rolph).

  19. 铵盐催化剂对木浆粘胶纤维热处理中结构与性能的影响%Effect of ammonium salt catalyst on structure and properties of wood-pulp viscose fiber during heat treatment

    Institute of Scientific and Technical Information of China (English)

    蔡蔚葵; 陈惠芳

    2016-01-01

    选择木浆粘胶纤维作为前驱体,采用催化剂硫酸铵[( NH4)2 SO4]和氯化铵( NH4 Cl)对粘胶纤维进行催化处理,制备粘胶基碳纤维。研究了催化剂对粘胶纤维在热处理过程中纤维结构与性能的影响。结果表明:( NH4)2 SO4和NH4 Cl均能有效降低纤维的初始热失重温度和失重率,NH4 Cl对失重温度降低的幅度较大,( NH4)2 SO4对失重率降低的幅度较大;在高温下铵盐催化剂均会与纤维素发生反应生成有机胺盐,达到催化的目的;在低温热处理过程中,随着温度的升高,纤维取向度先降低后升高,在210℃左右,取向度到达最低点;在热处理结束时,经( NH4)2 SO4处理的纤维的取向度要比经NH4 Cl处理的高,纤维内部结构排列更加有序,有利于后续碳化工艺的进行;( NH4)2 SO4的催化效果要比NH4 Cl的好。%Wood-pulp viscose fiber was used as a precursor and treated with ammonium sulfate ( NH4 ) 2 SO4 and ammonium chloride NH4 Cl catalysts to produce a rayon-based carbon fiber .The effects of the catalysts on the structure and properties of the viscose fiber were studied during heat treatment .The results showed that (NH4)2SO4 and NH4Cl could efficiently decrease the initial thermal weight loss temperature and weight loss rate;NH4 Cl caused the greater decrease of weight loss temperature when ( NH4 ) 2 SO4 caused the greater decrease of the weight loss rate;the ammonium salt catalysts provided the catalytic effect by reac-ting with cellulose to generate organic ammonium salt at high temperatures;the degree of orientation of the fiber was decreased to a minimum value at 210 ℃ and then increased while elevating the temperature during the low-temperature heat treatment; as compared with NH4Cl, (NH4)2SO4 contributed the higher degree of orientation and the more uniform internal structure arrange -ment to the fiber at the end of heat treatment , which was beneficial

  20. Reactive Uptake of Dimethylamine by Ammonium Sulfate and Ammonium Sulfate-Sucrose Mixed Particles.

    Science.gov (United States)

    Chu, Yangxi; Chan, Chak K

    2017-01-12

    Short-chain alkyl amines can undergo gas-to-particle partitioning via reactive uptake by ammonium salts, whose phases have been thought to largely influence the extent of amine uptake. Previous studies mainly focused on particles of single ammonium salt at either dry or wet conditions without any addition of organic compounds. Here we report the uptake of dimethylamine (DMA) by ammonium sulfate (AS) and AS-sucrose mixed particles at different relative humidities (RHs) using an electrodynamic balance coupled with in situ Raman spectroscopy. DMA is selected as a representative of short-chain alkyl amines, and sucrose is used as a surrogate of viscous and hydrophilic organics. Effective DMA uptake was observed for most cases, except for the water-limiting scenario at <5% RH and the formation of an ultraviscous sucrose coating at 10% RH and below. DMA uptake coefficients (γ) were estimated using the particle mass measurements during DMA uptake. Addition of sucrose can increase γ by absorbing water or inhibiting AS crystallization and decrease γ by elevating the particle viscosity and forming a coating layer. DMA uptake can be facilitated for crystalline AS or retarded for aqueous AS with hydrophilic viscous organics (e.g., secondary organic material formed via the oxidation of biogenic volatile organic compounds) present in aerosol particles.

  1. 21 CFR 573.914 - Salts of volatile fatty acids.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Salts of volatile fatty acids. 573.914 Section 573... Food Additive Listing § 573.914 Salts of volatile fatty acids. (a) Identity. The food additive is a... contains ammonium or calcium salts of volatile fatty acids and shall conform to the...

  2. Inorganic salt mixtures as electrolyte media in fuel cells

    Science.gov (United States)

    Angell, Charles Austen (Inventor); Belieres, Jean-Philippe (Inventor); Francis-Gervasio, Dominic (Inventor)

    2012-01-01

    Fuel cell designs and techniques for converting chemical energy into electrical energy uses a fuel cell are disclosed. The designs and techniques include an anode to receive fuel, a cathode to receive oxygen, and an electrolyte chamber in the fuel cell, including an electrolyte medium, where the electrolyte medium includes an inorganic salt mixture in the fuel cell. The salt mixture includes pre-determined quantities of at least two salts chosen from a group consisting of ammonium trifluoromethanesulfonate, ammonium trifluoroacetate, and ammonium nitrate, to conduct charge from the anode to the cathode. The fuel cell includes an electrical circuit operatively coupled to the fuel cell to transport electrons from the cathode.

  3. Adjusting ammonium uptake via phosphorylation.

    Science.gov (United States)

    Lanquar, Viviane; Frommer, Wolf B

    2010-06-01

    In plants, AMT/MEP/Rh superfamily mediates high affinity ammonium uptake. AMT/MEP transporters form a trimeric complex, which requires a productive interaction between subunits in order to be functional. The AMT/MEP C-terminal domain is highly conserved in more than 700 AMT homologs from cyanobacteria to higher plants with no cases found to be lacking this domain. AMT1;1 exists in active and inactive states, probably controlled by the spatial positioning of the C-terminus. Ammonium triggers the phosphorylation of a conserved threonine residue (T460) in the C-terminus of AMT1;1 in a time- and concentration-dependent manner. The T460 phosphorylation level correlates with a decrease of root ammonium uptake. We propose that ammonium-induced phosphorylation modulates ammonium uptake as a general mechanism to protect against ammonium toxicity.

  4. Ammonium assimilation in cyanobacteria.

    Science.gov (United States)

    Muro-Pastor, M Isabel; Reyes, Jose C; Florencio, Francisco J

    2005-01-01

    In cyanobacteria, after transport by specific permeases, ammonium is incorporated into carbon skeletons by the sequential action of glutamine synthetase (GS) and glutamate synthase (GOGAT). Two types of GS (GSI and GSIII) and two types of GOGAT (ferredoxin-GOGAT and NADH-GOGAT) have been characterized in cyanobacteria. The carbon skeleton substrate of the GS-GOGAT pathway is 2-oxoglutarate that is synthesized by the isocitrate dehydrogenase (IDH). In order to maintain the C-N balance and the amino acid pools homeostasis, ammonium assimilation is tightly regulated. The key regulatory point is the GS, which is controlled at transcriptional and posttranscriptional levels. The transcription factor NtcA plays a critical role regulating the expression of the GS and the IDH encoding genes. In the unicellular cyanobacterium Synechocystis sp. PCC 6803, NtcA controls also the expression of two small proteins (IF7 and IF17) that inhibit the activity of GS by direct protein-protein interaction. Cyanobacteria perceive nitrogen status by sensing the intracellular concentration of 2-oxoglutarate, a signaling metabolite that is able to modulate allosterically the function of NtcA, in vitro. In vivo, a functional dependence between NtcA and the signal transduction protein PII in controlling NtcA-dependent genes has been also shown.

  5. New Synthetic Approaches to Multifunctional Phenazinium Salt Derivatives

    Directory of Open Access Journals (Sweden)

    Vladimir N. Silnikov

    2003-06-01

    Full Text Available Two different approaches are offered for the synthesis under mild conditions of disubstituted phenazinium and benzo[a]phenazinium salts. Direct nucleophilic substitutions by primary and secondary amines in quaternary phenazinium salts containing an additional positive charge in the aliphatic part of the molecule were carried out. The substitution proceeds successively in positions 2 and 7, which allows selective introduction of different substituents into the heterocycle. Direct nucleophilic substitution in quaternary 2-N-alkyl-acetamidophenazinium and 5-alkoxy-benzo[a]phenazinium salts with different amines can also serve as a convenient method for the introduction of two different substituents.

  6. Acrylate Functionalized Tetraalkylammonium Salts with Ionic Liquid Properties

    Directory of Open Access Journals (Sweden)

    Silvia Janietz

    2012-05-01

    Full Text Available Acrylate functionalized ionic liquids based on tetraalkylammonium salts with terminal acrylates- and methylacrylates were synthesized. Melting points and ionic conductivity of twenty compounds in six groups were determined. Within one group the effect of three different counterions was investigated and discussed. The groups differ in cationic structure elements because of their functional groups such as acrylate and methacrylate, alkyl residues at the nitrogen and number of quaternary ammonium atoms within the organic cation. The effect of these cationic structure elements has been examined concerning the compiled parameters with a view to qualifying them as components for solid state electrolytes. The newly synthesized ionic liquids were characterized by NMR and FTIR analysis. The exchange of halide ions like bromide as counter ions to weakly coordinating [PF6], [OTf] or [TFSI] reduces the melting points significantly and leads to an ion conductivity of about 10−4 S/cm at room temperature. In the case of the dicationic ionic liquid, an ion conductivity of about 10−3 S/cm was observed.

  7. Application of Neesler reagent in the ammonium quantification used in the fermentations of biotechnology products

    Directory of Open Access Journals (Sweden)

    Dinorah Torres-Idavoy

    2015-08-01

    Full Text Available The ammonium salts are used in fermentations to supplement the deficient amounts of nitrogen and stabilize the pH of the culture medium. The excess ammonium ion exerts a detrimental effect on the fermentation process inhibiting microbial growth. An analytical method based on Neesler reagent was developed for monitoring and controlling the concentration of ammonium during the fermentation process. The test was standardized, by means of the selection of measuring equipment, and the reaction time as well as comparing standards of ammonium salts. The method was characterized with the evaluation of the next parameters: Specificity, Linearity and Range, Quantification Limit, Accuracy and Precision. The method proved to be specific. Two linear curves were defined in the ranges of concentrations of ammonium chloride salt (2-20 μg/ml and ammonium sulfate salt (5-30 μg/ml. The limits of quantification were the lowest points of each one. The method proved to be accurate and precise. This assay was applied to samples of the yeast culture and bacteria of the genus Saccharomyces and E. coli respectively. A novel method in micro plate for quantification and analytical control of ammonia was developed. This method is used to control this fundamental chemical component in the fermentations, to optimize the culture medium. Thus, an appropriate expression of recombinant proteins and proper vaccine candidates for clinical use are achieved

  8. Hydrolysed ginseng-saponin quaternary: a novel conditioning agent for hair care products.

    Science.gov (United States)

    Young-Dae, K; Chang-Kew, K; Chung-Nam, L; Byung-Jo, H

    1989-10-01

    Synopsis A new quaternary ammonium compound, hydrolysed ginseng-saponin quaternary (HGSQ), from Korean ginseng saponin and 2,3-epoxypropyltrimethyl ammonium chloride, has been developed as a conditioning agent for hair care products. This structure has a hydrophobic group from the aglycone of ginseng saponin which is biologically active and considered as the most important component of Korean ginseng. Its properties of surface tension, conductivity, critical micelle concentration (CMC), eye irritation, sorption onto hair, tensile strength for 20% extension and moisture retention effect were studied. Its cationic character allows the molecule to be more substantive than ginseng saponin. HGSQ had good physical properties and was safe enough as a cosmetic raw material. Also half-head tests of HGSQ-containing shampoo were carried out to evaluate the conditioning effects in shampoos. HGSQ showed good conditioning properties in a shampoo.

  9. Processo de organofilização de vermiculia brasileira com cloreto de cetiltrimetilamônio Organophilization process of Brazilian vermiculite with cetyltrimethyl ammonium chloride

    Directory of Open Access Journals (Sweden)

    E. V. D Gomes

    2010-03-01

    Full Text Available A vermiculita, argila da família dos aluminossilicatos 2:1 proveniente do estado de Goiás, Brasil, foi utilizada para a produção de uma argila organofílica. A vermiculita foi primeiramente submetida ao tratamento com cloreto de sódio para a obtenção de uma argila homoiônica sódica. A argila organofílica foi, então, obtida a partir da síntese com o sal de amônio quaternário, cloreto de cetiltrimetil amônio. As argilas, tratada com o sal orgânico e a não tratada, foram caracterizadas por espectrometria de fluorescência de raios X, espectroscopia de absorção na região do infravermelho, difração de raios X e análise termogravimétrica. Os resultados de fluorescência de raios X evidenciaram a mudança na composição química da vermiculita após as reações de troca com NaCl e sal orgânico. Os resultados obtidos por espectroscopia de absorção na região do infravermelho mostraram a presença dos grupos característicos do sal na argila e os de difração de raios X confirmaram sua intercalação entre as camadas da argila. Os resultados de análise termogravimétrica mostraram que a argila organofílica apresentou outras faixas de decomposição, além daquelas apresentadas pela vermiculita natural, correspondentes à decomposição do sal de amônio quaternário.The vermiculite (VMT, 2:1 aluminosilicate family clay from the state of Goiás, Brazil, was used for the production of an organophilic clay. First, the VMT was treated with sodium chloride to obtain the homo-ionic sodium clay. The organophilic clay was, then, obtained from the reaction with the quaternary ammonium salt, cetyltrimethyl ammonium chloride. The clay treated with organic salt and the untreated one were characterized by X-ray fluorescence spectrometry (XRF, Fourier transform infrared spectroscopy (FTIR, X-ray diffraction (XRD and thermogravimetric analysis (TGA. The results of XRF evidenced the change in the chemical composition of the VMT after the

  10. Ammonium diphosphitoindate(III

    Directory of Open Access Journals (Sweden)

    Farida Hamchaoui

    2013-04-01

    Full Text Available The crystal structure of the title compound, NH4[In(HPO32], is built up from InIII cations (site symmetry 3m. adopting an octahedral environment and two different phosphite anions (each with site symmetry 3m. exhibiting a triangular–pyramidal geometry. Each InO6 octahedron shares its six apices with hydrogen phosphite groups. Reciprocally, each HPO3 group shares all its O atoms with three different metal cations, leading to [In(HPO32]− layers which propagate in the ab plane. The ammonium cation likewise has site symmetry 3m.. In the structure, the cations are located between the [In(HPO32]− layers of the host framework. The sheets are held together by hydrogen bonds formed between the NH4+ cations and the O atoms of the framework.

  11. Synthesis, antimicrobial activity of lamotrigine and its ammonium derivatives

    Indian Academy of Sciences (India)

    Yong Qian; Peng-Cheng Lv; Lei Shi; Rui-Qin Fang; Zhong-Cheng Song; Hai-Liang Zhu

    2009-07-01

    Antiepileptic drug lamotrigine and its thirteen ammonium salt complexes (4a-4m) were synthesized and characterized by IR, elemental analysis, 1H-NMR, and MS spectral methods. Many of the ammonium salts (4a-4m) were first reported. Furthermore, the crystal structure of compound 3 was determined by single crystal X-ray diffraction analysis. All these complexes were tested in vitro for their antibacterial activity (Bacillus subtilis, Staphylococcus aureus, Enterococus faecalis, Escherichia coli, Pseudomonas aeruginosa and Enterobacter cloacae). The results indicated that most of the complexes showed good antibacterial activity against Gram-positive (B. subtilis, S. aureus and S. faecalis), but showed mild, even inactive against Gram-negative bacterial strains.

  12. Paleosols in central Illinois as potential sources of ammonium in groundwater

    Science.gov (United States)

    Glessner, J.J.G.; Roy, W.R.

    2009-01-01

    Glacially buried paleosols of pre-Holocene age were evaluated as potential sources for anomalously large concentrations of ammonium in groundwater in East Central Illinois. Ammonium has been detected at concentrations that are problematic to water treatment facilities (greater than 2.0 mg/L) in this region. Paleosols characterized for this study were of Quaternary age, specifically Robein Silt samples. Paleosol samples displayed significant capacity to both store and release ammonium through experiments measuring processes of sorption, ion exchange, and weathering. Bacteria and fungi within paleosols may significantly facilitate the leaching of ammonium into groundwater by the processes of assimilation and mineralization. Bacterial genetic material (DNA) was successfully extracted from the Robein Silt, purified, and amplified by polymerase chain reaction to produce 16S rRNA terminal restriction fragment length polymorphism (TRFLP) community analyses. The Robein Silt was found to have established diverse and viable bacterial communities. 16S rRNA TRFLP comparisons to well-known bacterial species yielded possible matches with facultative chemolithotrophs, cellulose consumers, nitrate reducers, and actinomycetes. It was concluded that the Robein Silt is both a source and reservoir for groundwater ammonium. Therefore, the occurrence of relatively large concentrations of ammonium in groundwater monitoring data may not necessarily be an indication of only anthropogenic contamination. The results of this study, however, need to be placed in a hydrological context to better understand whether paleosols can be a significant source of ammonium to drinking water supplies. ?? 2009 National Ground Water Association.

  13. Waterproofing Materials for Ammonium Nitrate

    Directory of Open Access Journals (Sweden)

    R.S. Damse

    2004-10-01

    Full Text Available This study explores the possibility of overcoming the problem of hygroscopicity of ammonium nitrate by coating the particles with selected waterproofing materials. Gravimetric analysis ofthe samples of ammonium nitrate coated with eight different waterproofing materials, vis-a-vis, uncoated ammonium nitrate, were conducted at different relative humidity and exposuretime. The results indicate that mineral jelly is the promising waterproofing material for ammonium nitrate among the materials tested, viz, calcium stearate, dioctyl phthalate, kaoline, diethylphthalate, dinitrotoluene, shelac varnish, and beeswax. Attempts were made to confirm the waterproofing ability of mineral jelly to ammonium nitrate using differential thermal analysisand x-ray diffraction patterns as an experimental tool. Suitability of mineral jelly as an additive for the gun propellant was also assessed on the basis of theoretical calculations using THERMprogram.

  14. Ammonium Perchlorate and Ammonium Perchlorate- Hydroxyl Terminated Polybutadiene Simulated Combustion

    Directory of Open Access Journals (Sweden)

    Rene Francisco Boschi Gonçalves

    2012-03-01

    Full Text Available The combustion simulation of ammonium perchlorate was carried out with the software Chemkin, in two steps: the burning behavior of pure ammonium perchlorate and the one of formulated ammonium perchlorate with hydroxyl terminated polybutadiene binder. In both cases, the room pressure varied in order to verify its influence in the system. The burning environment conditions were diverse. During the combustion process, the data obtained from the kinetic chemistry simulation software were compiled. The flame structure can be described by the molar fraction of the burning products and the temperature evolution from the surface of the material.

  15. Ammonium nitrate: a promising rocket propellant oxidizer

    Science.gov (United States)

    Oommen; Jain

    1999-06-30

    Ammonium nitrate (AN) is extensively used in the area of fertilizers and explosives. It is present as the major component in most industrial explosives. Its use as an oxidizer in the area of propellants, however, is not as extensive as in explosive compositions or gas generators. With the growing demand for environmental friendly chlorine free propellants, many attempts have been made of late to investigate oxidizers producing innocuous combustion products. AN, unlike the widely used ammonium perchlorate, produces completely ecofriendly smokeless products. Besides, it is one of the cheapest and easily available compounds. However, its use in large rocket motors is restricted due to some of its adverse characteristics like hygroscopicity, near room temperature phase transformation involving a volume change, and low burning rate (BR) and energetics. The review is an attempt to consolidate the information available on the various issues pertaining to its use as a solid propellant oxidizer. Detailed discussions on the aspects relating to phase modifications, decomposition chemistry, and BR and energetics of AN-based propellants, are presented. To make the review more comprehensive brief descriptions of the history, manufacture, safety, physical and chemical properties and various other applications of the salt are also included. Copyright 1999 Elsevier Science B.V.

  16. Volatile Corrosion Inhibitors Part III- Ammonium stearate and M-Dinitrobenezene

    Directory of Open Access Journals (Sweden)

    K. S. Rajagopalan

    1962-07-01

    Full Text Available In earlier studies while screening various chemical compound for their vapour phase inhibiting properties. Some ammonium salts and nitro-compounds had shown promising results. Of these, ammonium stearate and m-dinitrobenzene gave the best results in accelerated short term tests. In the present paper a more detailed investigation on the corrosion protection given by them has been made.Ammonium stearate and m-dinitrobenzene, both, have been found to perform satisfactorily under all test conditions except SOsub2 test where m-dinitrobenzene failed. Their indigenous availability, low cost and good corrosion inhibiting properties demands favorable consideration for their adoption as VCIs for general use.

  17. Headspace Analysis of Ammonium Nitrate

    Science.gov (United States)

    2017-01-25

    Naval Research Laboratory Washington, DC 20375-5320 NRL/MR/6110--17-9709 Headspace Analysis of Ammonium Nitrate January 25, 2017 Approved for public...TELEPHONE NUMBER (include area code) b. ABSTRACT c. THIS PAGE 18. NUMBER OF PAGES 17. LIMITATION OF ABSTRACT Headspace Analysis of Ammonium Nitrate G...isobutane reagent ion from analysis of ammonia desorbed from packed tungsten oxide sampling tube .................. 18 E-1 Executive Summary The

  18. Proposal to redefine the Quaternary

    Institute of Scientific and Technical Information of China (English)

    BradPillans

    2004-01-01

    The following proposal has been circulated, via the Executive of the International Union for Quaternary Research (INQUA), to all INQUA members for discussion. It also appears on the ICS web site (www.stratigraphy.org). Comments may be sent to John Clague, President of INQUA (jclague@sfu.ca), and Brad Pillans(brad.pillans@anu.edu.au).

  19. 21 CFR 184.1133 - Ammonium alginate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium alginate. 184.1133 Section 184.1133 Food... Specific Substances Affirmed as GRAS § 184.1133 Ammonium alginate. (a) Ammonium alginate (CAS Reg. No. 9005.... Ammonium alginate is prepared by the neutralization of purified alginic acid with appropriate pH...

  20. Synthesis of New N-Quaternary-3-benzamidoquinuclidinium Salts

    Directory of Open Access Journals (Sweden)

    Srdjanka Tomic

    2006-09-01

    Full Text Available The synthesis of racemic and enantiomerically pure N-p-methylbenzyl-3- and N-p-chlorobenzylbenzamidoquinuclidinium bromides (6-8 and 9-11, respectively is described. These compounds were prepared from racemic or enantiomerically pure 3-benzamidoquinuclidines 3-5 using the appropriate quaternization reagents: p-methyl- benzyl bromide (1 and p-chlorobenzyl bromide (2.

  1. 40 CFR 721.6183 - Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines...

    Science.gov (United States)

    2010-07-01

    ... - maleic anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine... Substances § 721.6183 Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow... anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine (PMN...

  2. The adsorption of alkyl-dimethyl-benzyl-ammonium chloride onto cotton nonwoven hydroentangled substrates at the solid-liquid interface is minimized by additive chemistries

    Science.gov (United States)

    Quaternary ammonium compounds, commonly referred to as quats, are cationic surfactants widely used as the active biocide ingredient for disposable disinfecting wipes. The cationic nature of quats results in a strong ionic interaction and adsorption onto wipes materials that have an anionic surface ...

  3. 2-羟丙基三甲基氯化铵壳聚糖的制备及其抗菌性分析%Characterization and Antimicrobial Activity of 2-Hydroxypropyltrimethyl Ammonium Chloride Chitosan

    Institute of Scientific and Technical Information of China (English)

    龚安华; 吴涛; 吴静; 钱琛

    2012-01-01

    The water-soluble quaternary ammonium salt of 2-hydroxypropyltrimethyl ammonium chloride chitosan (HTCC) was successfully prepared by the reaction of chitosan with 2, 3-epoxypropyl trimethyl ammonium chloride (CTA). The structure of HTCC was characterized by FTIR and 1H NMR, and in vitro antimicrobial activities of HTCC were investigated systematically. The results indicated that the non-woven fabrics which had been immersed in HTCC solution demonstrated good antimicrobial activity against Escherichia coli and Campylobacter jejuni. The minimum inhibitory concentration (MIC) of HTCC solution against C. Jejuni was 8 mg/mL. The results indicated that HTCC was a potential polymeric antimicrobial.%以2,3-环氧丙基三甲基氯化铵(GTA)和壳聚糖为原料制备水溶性的壳聚糖季铵盐2-羟丙基三甲基氯化铵壳聚糖(HTCC),采用傅立叶红外光谱仪(FTIR谱图)和核磁共振仪(1H-NMR图谱)表征HTCC的结构,并进行抗菌性研究.结果表明,HTCC溶液和浸泡过HTCC的无纺布对大肠杆菌(Escherichia coli)和空肠弯曲菌(Campylobacter jejuni)有抑菌效果,其中对空肠弯曲菌的最低抑菌浓度(MIC)为8mg/mL,说明HTCC是一种具有应用潜力的高分子抗菌剂.

  4. Fotodegradação de compósitos de poliestireno/argila montmorilonita: efeito do tipo de argila e presença de sal Photodegradation of polystyrene/montmorillonite clay: the effect of the type of clay and presence of salt

    Directory of Open Access Journals (Sweden)

    Camila F. de P. Oliveira

    2012-01-01

    Full Text Available Compósitos de poliestireno/montmorilonita (PS/MMT contendo 2,5% em peso de argila foram preparados com dois tipos de argila modificada com sais quaternários de amônio. Também foram preparadas amostras do PS + sal quaternário de amônio, utilizando-se proporção de sal semelhante à usada na modificação da argila. Todas as amostras foram expostas à radiação UV por períodos de até 12 semanas, e em seguida foram realizados testes para avaliar as modificações em massa molar, propriedades mecânicas (tração e impacto, estrutura química (FTIR e superfície de fratura (MEV dessas amostras. Os resultados mostraram que compostos metálicos existentes na argila catalisam o processo fotodegradativo do PS e a presença isolada do sal não altera significativamente o comportamento do PS frente à radiação UV.Composites of polystyrene/montmorillonite (PS/MMT containing 2.5 wt. (% clay were prepared with two types of clays modified with quaternary ammonium salts. Were also prepared samples of PS + quaternary ammonium salt, using the same amount employed in modifying the clay. All samples were exposed to UV radiation for up to 12 weeks, and then tests were conducted to evaluate the changes in molecular weight, mechanical properties (tensile and impact, chemical structure (FTIR and fracture surface (SEM of these samples. The results showed that metal compounds existing in clay catalyzes the photodegradation process of PS and the presence of salt alone does not significantly alter the behavior of PS under UV.

  5. Thermo gravimetric analysis of supramolecular complexes of p-tert-butylcalix[6]arene and ammonium cations: crystal structure of diethylammonium complex

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarotto, Marcio [Departamento de Quimica Organica, UFRGS, Av. Bento Goncalves 9500, CEP 91501 970, C.P. 15003, Porto Alegre, Rio Grande do Sul (Brazil)]. E-mail: marcio@iq.ufrgs.br; Nachtigall, Francine Furtado [Departamento de Quimica Organica, UFRGS, Av. Bento Goncalves 9500, CEP 91501 970, C.P. 15003, Porto Alegre, Rio Grande do Sul (Brazil); Schnitzler, Egon [Departamento de Quimica, Universidade Estadual de Ponta Grossa, Campus de Uvaranas, Av. General Carlos Cavalcanti 4748, CEP 84030 900 Ponta Grossa, Parana, Brazil. (Brazil); Castellano, Eduardo Ernesto [Departamento de Fisica, Universidade de Sao Paulo, Sao Carlos, Av. Trabalhador Saocarlense 400, Centro, CEP 13566-590, Sao Carlos, SP (Brazil)

    2005-05-01

    Thermo gravimetric analysis of ammonium-p-tert-butylcalix[6]arene salts were carried out to determine the stoichiometry of the inclusion compounds and the temperature of leaving of the ammonium cation, as amine, from the solid phase by a reverse proton transfer reaction to calixarene. The chain length of the amine molecules and their relative basicity order are the main factors which determine the decomplexation temperatures for the ammonium salts of piperidinium, diethylammonium, ethylenediammonium, morpholinium, s-butylammonium, butylammonium, hexylammonium and triethylammonium salts of p-tert-butylcalix[6]arene anion. The solid state structure of bis-diethylammonium-p-tert-butylcalix[6]arene dianion is reported. The calix moiety adopts a 1,2,3 alternate conformation, with one ammonium as exo-calix and other as endo-calix, with an intricate array of hydrogen bonds between phenol, phenolate and ammonium cations.

  6. Quaternary polymethacrylate-magnesium aluminum silicate films: molecular interactions, mechanical properties and tackiness.

    Science.gov (United States)

    Rongthong, Thitiphorn; Sungthongjeen, Srisagul; Siepmann, Juergen; Pongjanyakul, Thaned

    2013-12-15

    The aim of this study was to investigate the impact of the addition of magnesium aluminum silicate (MAS), a natural clay, on the properties of polymeric films based on quaternary polymethacrylates (QPMs). Two commercially available aqueous QPM dispersions were studied: Eudragit(®) RS 30D and Eudragit(®) RL 30D (the dry copolymers containing 5 and 10% quaternary ammonium groups, respectively). The composite QPM-MAS films were prepared by casting. Importantly, QPM interacted with MAS and formed small flocculates prior to film formation. Continuous films were obtained up to MAS contents of 19% (referred to the QPM dry mass). ATR-FTIR and PXRD revealed that the positively charged quaternary ammonium groups of QPM interacted with negatively charged SiO(-) groups of MAS, creating nanocomposite materials. This interaction led to improved thermal stability of the composite films. The puncture strength and elongation at break of dry systems decreased with increasing MAS content. In contrast, the puncture strength of the wet QPM-MAS films (upon exposure to acidic or neutral media) increased with increasing MAS content. Furthermore, incorporation of MAS into QPM films significantly decreased the latter's tackiness in the dry and wet state. These findings suggest that nanocomposite formation between QPM and MAS in the systems can enhance the strength of wet films and decrease their tackiness. Thus, MAS offers an interesting potential as novel anti-tacking agent for QPM coatings.

  7. Preparation of nanodispersed titania using stabilized ammonium nitrate melts

    KAUST Repository

    Raciulete, Monica

    2010-10-01

    An expedite one-step approach using simple precursors has been proposed to obtain metallic oxide compounds and exemplified by preparation of highly dispersed TiO2. The technique consists in heating to 400500 °C of molten ammonium nitrate stabilized with an organic nitrogen-containing compound (urea, melamine, ammonium oxalate) and containing dissolved metal salt precursor (TiOCl2). The crystallites of the resulting TiO2 demonstrated variable size and shape as a function of stabilizer used. Their activity in photocatalytic oxidation of formic acid also depends on the nature of the stabilizer. The catalysts as-prepared showed high photocatalytic performance, superior to that of the Degussa P25 reference. Nitrogen containing stabilizers play a double role of increasing the process safety and modifying the properties of the solid products. © 2010 Elsevier Inc. All rights reserved.

  8. Dimethyl-ammonium 3-carb-oxy-benzoate.

    Science.gov (United States)

    Siddiqui, Tausif; Koteswara Rao, Vandavasi; Zeller, Matthias; Lovelace-Cameron, Sherri R

    2012-06-01

    The asymmetric unit of the title organic salt, C(2)H(8)N(+)·C(8)H(5)O(4) (-), consists of two dimethyl-ammonium cations and two 3-carb-oxy-benzoate anions. The 3-carb-oxy-benzoate anions are linked via strong inter-molecular and nearly symmetrical O-H⋯O hydrogen bonds forming infinite chains parallel to [111]. Neighbouring chains are further connected by the dimethyl-ammonium cations via N-H⋯O bonds, resulting in a double-chain-like structure. The dihedral angles of all carboxylate groups with respect to the phenylene rings are in the range 7.9 (1)-20.48 (9)°.

  9. Preparation and characterization of ammonium-functionalized silica nanoparticle as a new adsorbent to remove methyl orange from aqueous solution

    Science.gov (United States)

    Liu, Jinshui; Ma, Shi; Zang, Lingjie

    2013-01-01

    Quaternary ammonium polyethylenimine (PEI) was successfully modified to silica nanoparticle (QPEI/SiO2) as a new adsorbent to remove methyl orange from aqueous solution. The isotherm and kinetics of dye adsorption were studied, which showed that Langmuir isotherm fit the experimental results well. The maximum adsorption capacity of QPEI/SiO2 for methyl orange is 105.4 mg/g. The equilibrium time for methyl orange adsorption onto QPEI/SiO2 was as short as 10 min, indicating that the adsorbent has a strong affinity for methyl orange. The adsorption capacities of the methyl orange are slightly influenced by the pH in the range of 3.2-9.6. The QPEI/SiO2 adsorbent can be used in the wide pH range, which is different from other adsorbent. This may attribute to the quaternary ammonium carrying positive charges in acidic and basic solution.

  10. Iodine catalyzed and tertiary butyl ammonium bromide promoted p reparation of b enzoxazaphosphininyl phenylboronates

    Directory of Open Access Journals (Sweden)

    K. R. Kishore K. Reddy,

    2009-05-01

    Full Text Available Benzoxazaphosphininyl Phenylboronates were prepared by O-Phosphorylation of potassium salt ofphenylboronic acid with cyclic phosphoromonochloridates in the presence of stoichiometric amount of Iodineand catalytic amount of tertiary butyl ammonium bromide at 50-60 °C in dry toluene.

  11. Chemical, biochemical, and microbiological aspects of chitosan quaternary salt as active coating on sliced apples Aspectos químicos, bioquímicos e microbiológicos de sais quaternários de quitosana para revestimento ativo de maçãs fatiadas

    Directory of Open Access Journals (Sweden)

    Douglas de Britto

    2012-09-01

    Full Text Available The biocompatibility of chitosan and chitosan quaternary salt coatings was evaluated for use as edible coatings for sliced apple. Measurement of water loss, color change, and fungal growth appearance were monitored as a function of time. A significant brownish effect was observed on chitosan coated slices, varying greatly from L* = 76.5 and Hue angle = 95.9° (t = 0 to L* = 45.3 and Hue angle = 69.8° (t = 3 days, whilst for TMC coated samples the variation was considerable lower (L* = 74.1; Hue angle = 95.0° to (L* = 67.0; Hue angle = 83.8° within the same period. The hydrosoluble derivative N,N,N-trimethylchitosan demonstrated good antifungal activity against P. expansum although highly dependent on the polymer properties such as degree of quaternization. The most efficient formulation was that prepared from derivative having a degree of quaternization of 45%, high solubility, and high viscosity. This formulation restrained fungus spreading up to 30%, while for the control it reached almost 80% of the total assessed surfaces during 7 days of storage.A biocompatibilidade de revestimentos baseados em quitosana e seus sais quaternários foi estudada visando seu emprego como revestimentos comestíveis de maçãs fatiadas. Medidas de perda de água, mudança de coloração e desenvolvimento de fungos foram monitoradas em função do tempo de estocagem. O efeito de escurecimento enzimático para fatias de maçãs recobertas com solução de quitosana foi bastante pronunciado, variando de L* = 76,5 e Ângulo de Hue = 95,9° (t = 0 a L* = 45,3 e Ângulo de Hue = 69,8° (t = 3 dias, ao passo que, para as amostras revestidas com TMC, a variação foi bem menor no mesmo período (L* = 74,1; Ângulo de Hue = 95,0° a (L* = 67,0; Ângulo de Hue = 83,8°. O derivado hidrossolúvel N,N,N-trimetilquitosana apresentou ótima atividade antifúngica contra P. expansum, mas muito dependente das propriedades do polímero como o grau de quaternização. A formula

  12. Enhanced sorption of polycyclic aromatic hydrocarbons to tetra-alkyl ammonium modified smectites via cation-pi interactions.

    Science.gov (United States)

    Qu, Xiaolei; Liu, Ping; Zhu, Dongqiang

    2008-02-15

    The objective of this study was to characterize molecular sorptive interactions of polycyclic aromatic hydrocarbons (PAHs) by organoclays modified with quaternary ammonium cations. Three PAHs, naphthalene (NAPH), phenanthrene (PHEN), and pyrene (PYR), and three chlorobenzenes, 1,2-dichlorobenzene (DCB), 1,2,4,5-tetrachlorobenzene (TeCB), and pentachlorobenzene (PtCB), were sorbed from aqueous solution to reference montmorillonite clays (SWy-2) exchanged respectively with tetramethyl ammonium (TMA), tetraethyl ammonium (TEA), tetra-n-butyl ammonium (TBA), and hexadecyltrimethyl ammonium (HDTMA) cations. Solute hydrophobicities are compared between PAHs and chlorobenzenes using the solute n-octanol-water partition coefficient, n-hexadecane-water partition coefficient, and polyethylene-water distribution coefficient. The PAHs show several- to more than 10-fold greater sorption than the chlorobenzenes having close hydrophobicities but fewer delocalized pi electrons (NAPH/DCB, PHEN/TeCB, and PYR/ PtCB) by TEA-, TBA-, and HDTMA-clays. Furthermore, the PAHs show greater trends of solubility enhancement than the compared chlorobenzenes by TMA, TEA, and TBA in aqueous solution. The enhanced sorption and aqueous solubility of PAHs are best described by cation-pi interactions between ammonium cations and PAHs relative to chlorobenzenes that are incapable of such interactions. Cation-pi complexation between PAHs and tetra-alkyl ammonium cations in chloroform was verified by ring-current-induced upfield chemical shifts of the alkyl groups of cations in the 1H NMR spectrum.

  13. Determination of ammonium in a buddingtonite sample by ion-chromatography

    Science.gov (United States)

    Klock, P.R.; Lamothe, P.J.

    1986-01-01

    An ion-chromatographic method for the direct determination of ammonium, potassium, and sodium in geologic materials is described. Samples are decomposed with a mixture of hydrofluoric and hydrochloric acids in a sealed polycarbonate bottle heated in a microwave oven. The ion-chromatograph separates the cations and determines them by conductivity measurement. The ammonium concentrations thus determined have been verified by use of an ammonia-specific electrode. A total of 32 analyses of ammonium salts by both techniques showed an average error of -4%, with a relative standard deviation (RSD) of 6%. The ammonium concentrations found in a buddingtonite sample had an RSD of 2.2% and their mean agreed with that obtained by the Kjeldahl method. By use of the prescribed dilution of the sample, detection limits of 0.1% can be achieved for all three cations. ?? 1986.

  14. 76 FR 62311 - Ammonium Nitrate Security Program

    Science.gov (United States)

    2011-10-07

    ... to best notify agents (AN Agents) when ammonium nitrate purchasers (AN Purchasers) submit those AN... directly to ammonium nitrate sellers (AN Sellers) when it is not possible for an AN Seller to verify the...

  15. Ammonium diamminesilver(I bis(5-chloro-2-hydroxybenzenesulfonate trihydrate

    Directory of Open Access Journals (Sweden)

    Zhao-Peng Deng

    2012-02-01

    Full Text Available The reaction of silver nitrate with 5-chloro-2-hydroxybenzenesulfonic acid in the presence of ammonia yielded the title salt, (NH4[Ag(NH32](C6H4ClO4S2·3H2O. The AgI ion shows linear coordination [N—Ag—N = 175.2 (1 °]. The ammonium and diamminesilver cations, the benzenesulfonate anion and the lattice water molecules interact through an intricate network of N—H...O and O—H...O hydrogen bonds to form a three-dimensional network.

  16. Advanced regeneration and fixed-bed study of ammonium and potassium removal from anaerobic digested wastewater by natural zeolite.

    Science.gov (United States)

    Guo, Xuejun; Zeng, Larry; Jin, Xin

    2013-05-01

    Highly efficient regeneration of natural zeolite was developed in conjunction with the removal of high concentrations of ammonia and potassium from the reverse osmosis effluent of anaerobic-digested wastewater by fixed-bed ion exchange. The elution and uptake behavior of ammonium and potassium in the fixed bed were studied. Both batch desorption tests and on-column regeneration were conducted to develop an optimum regeneration condition compatible with the wastewater requirements. The effectiveness of ammonium elution increased with increasing alkaline concentration. The increase of salt dose significantly enhanced the ammonium maximum in the elution solution. Complete ammonium elution was achieved in 6 bed volumes (BV) when the alkaline and salt concentrations were respectively 0.1 mol/L and 18.6 g/L at a flow rate of 2.5-3.0 BV/hr. Due to the higher affinity of potassium with natural clinoptilolite, complete potassium elution was not achieved in all cases.

  17. 21 CFR 582.7133 - Ammonium alginate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ammonium alginate. 582.7133 Section 582.7133 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Ammonium alginate. (a) Product. Ammonium alginate. (b) Conditions of use. This substance is...

  18. 21 CFR 582.1141 - Ammonium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ammonium phosphate. 582.1141 Section 582.1141 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1141 Ammonium phosphate. (a) Product. Ammonium phosphate (mono- and dibasic). (b)...

  19. 76 FR 11273 - Ammonium Nitrate From Russia

    Science.gov (United States)

    2011-03-01

    ... COMMISSION Ammonium Nitrate From Russia AGENCY: United States International Trade Commission. ACTION: Institution of a five-year review concerning the suspended investigation on ammonium nitrate from Russia... investigation on ammonium nitrate from Russia would be likely to lead to continuation or recurrence of...

  20. 76 FR 47238 - Ammonium Nitrate From Russia

    Science.gov (United States)

    2011-08-04

    ... COMMISSION Ammonium Nitrate From Russia Determination On the basis of the record \\1\\ developed in the subject... order on ammonium nitrate from Russia would be likely to lead to continuation or recurrence of material... Commission are contained in USITC Publication 4249 (August 2011), entitled Ammonium Nitrate from...

  1. Antibacterial activity and characteristics of modified ferrite powder coated with a gemini pyridinium salt molecule.

    Science.gov (United States)

    Shirai, Akihiro; Maeda, Takuya; Ohkita, Motoaki; Nagamune, Hideaki; Kourai, Hiroki

    2007-09-01

    This report describes the synthesis of an antibacterial material consisting of a gemini quaternary ammonium salt (gemini-QUAT) immobilized on ferrite powder, and its antibacterial activity. A gemini-QUAT containing two pyridinium residues per molecule, 4,4'-[1,3-(2,2-dihydroxylmethyl-1,3-dithiapropane)]bis (1-octylpyridinium bromide), was immobilized on ferrite powder by a reaction between the hydroxyl group of the QUAT and trimethoxysilane. Immobilization of the gemini-QUAT on ferrite (F-gemini-QUAT) was confirmed when the dye, bromophenol blue, was released from F-gemini-QUAT-dye after contact between ferrite and the dye. Elemental analysis of the QUAT-ferrite determined the molar amount of QUAT on the ferrite. The antibacterial effect of the ferrite was investigated using a batch treatment system, and this effect was compared with that of another QUAT-ferrite (F-mono-QUAT) binding a mono-QUAT, which possesses one pyridinium residue, prepared by the same immobilization method as F-gemini-QUAT. Results indicated the F-gemini QUAT possessed a higher bactericidal potency and broader antibacterial spectrum compared to F-mono-QUAT. In addition, this study suggested that gemini-QUATs possessed high bactericidal potency without being influenced by immobilization to materials, and the antibacterial activity and characteristics of F-gemini-QUAT could be attributed to the unique structure of the immobilized gemini-QUAT.

  2. Polymerization and photochromism of ammonium molybdate in porous glass

    Science.gov (United States)

    Pak, V. N.; Borisov, A. N.

    2016-08-01

    Modification of porous glass (PG) plates is carried out by impregnation with aqueous solutions of ammonium molybdate (NH4)2MoO4 with subsequent removal of water at 120°C. A long-wavelength shift of absorption spectra upon accumulation of the salt in PG indicates polymerization of MoO 4 2- anions at low concentrations of the encapsulated salt. Photochromism manifests itself as the anionic forms in PG become larger. UV irradiation of the modified plates causes enhancement of continuous absorption in the visible range. The proposed mechanism of photoreduction of the polianions in PG involves the removal of oxygen atoms from the bridging-Mo-O-Mo-bonds and stabilization of the colored forms by means of conjugation of the electrons released from the 4 d-levels of pentavalent molybdenum.

  3. Phase diagram of ammonium nitrate

    Science.gov (United States)

    Dunuwille, M.; Yoo, C. S.

    2014-05-01

    Ammonium Nitrate (AN) has often subjected to uses in improvised explosive devices, due to its wide availability as a fertilizer and its capability of becoming explosive with slight additions of organic and inorganic compounds. Yet, the origin of enhanced energetic properties of impure AN (or AN mixtures) is neither chemically unique nor well understood -resulting in rather catastrophic disasters in the past1 and thereby a significant burden on safety in using ammonium nitrates even today. To remedy this situation, we have carried out an extensive study to investigate the phase stability of AN at high pressure and temperature, using diamond anvil cells and micro-Raman spectroscopy. The present results confirm the recently proposed phase IV-to-IV' transition above 17 GPa2 and provide new constraints for the melting and phase diagram of AN to 40 GPa and 400 °C.

  4. Preparation and Properties of Antifouling Coatings Based on Quaternary Ammonium Salt Polymer/Blocked Polyurethane Blends%季铵盐聚合物/封端聚氨酯共混物防污涂料的制备与性能

    Institute of Scientific and Technical Information of China (English)

    李亮; 晏欣; 刘明光; 张梦; 王源升

    2015-01-01

    用溶液聚合法合成了甲基丙烯酸缩水甘油醚-甲基丙烯酸丁酯共聚物,然后通过共聚物中环氧基与盐酸和三甲胺的反应制备了相应的季铵盐聚合物(QASP),并制备了QASP/封端聚氨酯(BPU)共混物防污涂料.测试结果表明,随着共混物涂料中BPU用量的增加,涂层的拉伸强度下降,断裂伸长率增加,剪切强度增加;氧化亚铜能增强涂层的疏水性和降低涂层的表面能;防污涂料中铜离子渗出率保持在比较高的水平,防污性能比较明显.

  5. Washburn高度法对新型双季铵盐复配改性膨润土的润湿性研究%The Washburn Height Rise Method Used to Study the Wettability of Bentonite Modified by New Type Compounded Bis-Quaternary Ammonium Salts

    Institute of Scientific and Technical Information of China (English)

    胡昭朝; 高芒来; 谷峥; 罗忠新; 薛广海

    2013-01-01

    Washburn’s equation is a useful tool for studying the wettability of powder, but it has certain limitation in practice. In this paper, Washburn’s equation was transformed and its reliability was identified through the water and n-heptane wettability of bentonite modified by hexamethyl ethyl diammonium methylsulfate (EDAS) mixed with hexamethyl hexyl diammonium methylsulfate (HDAS). In addition, the effects of different concentrations and component ratios of the modifier on the wettability of modified bentonite were compared. The results show that the water wettability of modified bentonite is stronger than that of sodium bentonite, while the n-heptane wettability of modified bentonite is weaker. Meanwhile, the order of modifying has little effect on the water wettability of 50% HDAS, and the water wettability of bentonite modified with 25%HDAS and 75%HDAS are stronger than that of bentonite modified with any other component ratios. The oil water relative wettability coefficientβreaches its highest value when bentonite modified with 25%HDAS at 1.5 CEC, which indicates that the wettability of strong oil-wet rock can be converted by bentonite modified with such condition.%  Washburn方程是研究粉体对液体润湿性的有效工具,但实际使用存在一定的局限性。今对 Washburn方程进行了变换,并通过六甲基乙二铵二甲硫酸盐(EDAS)与六甲基己二铵二甲硫酸盐(HDAS)复配改性膨润土对水和正庚烷的润湿性验证了变换Washburn方程的可靠性,并比较了不同改性浓度及复配比例对膨润土润湿性的影响。结果表明,与钠土相比,改性膨润土对水的润湿性均有较大程度的增强,而对正庚烷的润湿性均有一定程度的减弱。50%复配比例下改性先后顺序对膨润土的水润湿性影响较小,25%HDAS和75%HDAS改性膨润土的水润湿性均较其他复配比例强。1.5CEC,25%HDAS的油水相对润湿系数β值最大,该条件下改性剂可使强亲油岩石润湿性发生改变。

  6. 反应性壳聚糖季铵盐的合成及其在柞丝绸抗菌整理上的应用%Synthesis of reactive quaternary ammonium salt of chitosan and its application on antibacterial finishing of tussah silk

    Institute of Scientific and Technical Information of China (English)

    路艳华; 刘治梅; 林杰

    2010-01-01

    为提高壳聚糖的水溶性,并增强其与纤维之间的结合力,采用壳聚糖与2,3-环氧丙基三甲基氯化铵反应,合成了水溶性的2-羟丙基三甲基氯化铵壳聚糖(壳聚糖季铵盐),再将壳聚糖季铵盐与N-羟甲基丙烯酰胺进一步反应,合成了带有纤维反应性基团的水溶性O-甲基丙烯酰胺壳聚糖季铵盐(反应性壳聚糖季铵盐),用傅里叶红外光谱表征了所合成的壳聚糖季铵盐、反应性壳聚糖季铵盐和处理前后柞蚕丝的结构,研究了经反应性壳聚糖季铵盐整理后柞丝绸的抗菌性能.结果表明:经整理的柞丝绸洗涤20次后,对金黄色葡萄球菌和大肠杆菌的抑菌率均高于90%.

  7. Dental plaque microcosm biofilm behavior on a resin composite incorporated with nano-antibacterial inorganic filler containing long-chain alkyl quaternary ammonium salt%含长链烷基季铵盐纳米抗菌无机填料的复合树脂对人牙菌斑生物膜的影响

    Institute of Scientific and Technical Information of China (English)

    吴峻岭; 张强; 孙睿男; 朱婷; 葛建华; 周传健

    2015-01-01

    目的 合成含长链烷基季铵盐纳米抗菌无机填料的复合树脂,探讨其对人牙菌斑生物膜的影响.方法 制备含长链烷基季铵盐的纳米抗菌二氧化硅填料,经表面偶联处理后,分别以0%、5%、10%、15%及20%的质量分数添加到复合树脂中,以0%组作为对照组,用三点弯曲试验来检测其力学性能.建立人牙菌斑生物膜体外模型,通过菌落计数、乳酸代谢分析及活/死细菌染色等手段来评价复合树脂对人牙菌斑生物膜的影响.结果 与对照组相比,当复合树脂纳米抗菌无机填料的质量分数小于15%时,其力学性能没有明显改变(p>0.05);当纳米抗菌无机填料的质量分数达到5%及以上时,复合树脂对人牙菌斑生物膜的代谢产生明显的抑制作用,显示出良好的抗菌性能(P<0.05).结论 当抗菌无机填料的质量分数达到5%时,复合树脂具有较强的抗菌防龋功能.

  8. The preparation of blend membrane about quaternary ammonium salt of chitosan/waterborne polyurethane and its waterproof and breathable properties%季铵盐壳聚糖/水性聚氨酯共混膜的制备及防水透湿性能

    Institute of Scientific and Technical Information of China (English)

    刘玉章; 尉霞; 章媛媛

    2011-01-01

    将季铵盐壳聚糖( HACC)与水性聚氨酯(WPU)进行共混,对共混膜进行了耐静水压、透湿量性能测试.讨论了HACC用量、共混时间、烘干温度对共混膜防水透湿性能的影响.结果表明,当HACC用量10%~15%,共混时间15~20min,烘干温度100~110℃时,制备的共混膜具有良好的防水透湿性能及共混性能.%In order to further enrich cashmere product category and utilize cashmere resource more rationally, a type of light and thin worsted blending fabric is successfully developed. It was used wool, mulberry silk fiber and cashmere fiber as raw materials, and mainly to the technological process and key techniques through the re-combing, spinning, weaving and finishing four parts to feasible treatment technology. This topic of research and development the superb properties of wool, mulberry silk fiber and cashmere fibers contribute to the superior quality of high count yarn, best quality and superior product performance reduce the consumption of raw material, improves the grade of the product.

  9. A Quaternary Polybenzimidazole Membrane for Intermediate Temperature Polymer Electrolyte Membrane Fuel Cells

    DEFF Research Database (Denmark)

    Xu, C.; Scott, K.; Li, Qingfeng

    2013-01-01

    A quaternary ammonium polybenzimidazole (QPBI) membrane was synthesized for applications in intermediate temperature (100–200 °C) hydrogen fuel cells. The QPBI membrane was imbibed with phosphoric acid to provide suitable proton conductivity. The proton conductivity of the membrane was 0.051 S cm–1...... at 150 °C with the PA acid loading level of 3.5 PRU (amount of H3PO4 per repeat unit of polymer QPBI). The QPBI membrane was characterized in terms of composition, structure and morphology by NMR, FTIR, SEM, and EDX. The fuel cell performance with the membrane gave peak power densities of 440 and 240 m...

  10. Novel Quaternary Quantum Decoder, Multiplexer and Demultiplexer Circuits

    Science.gov (United States)

    Haghparast, Majid; Monfared, Asma Taheri

    2017-05-01

    Multiple valued logic is a promising approach to reduce the width of the reversible or quantum circuits, moreover, quaternary logic is considered as being a good choice for future quantum computing technology hence it is very suitable for the encoded realization of binary logic functions through its grouping of 2-bits together into quaternary values. The Quaternary decoder, multiplexer, and demultiplexer are essential units of quaternary digital systems. In this paper, we have initially designed a quantum realization of the quaternary decoder circuit using quaternary 1-qudit gates and quaternary Muthukrishnan-Stroud gates. Then we have presented quantum realization of quaternary multiplexer and demultiplexer circuits using the constructed quaternary decoder circuit and quaternary controlled Feynman gates. The suggested circuits in this paper have a lower quantum cost and hardware complexity than the existing designs that are currently used in quaternary digital systems. All the scales applied in this paper are based on Nanometric area.

  11. Novel Quaternary Quantum Decoder, Multiplexer and Demultiplexer Circuits

    Science.gov (United States)

    Haghparast, Majid; Monfared, Asma Taheri

    2017-02-01

    Multiple valued logic is a promising approach to reduce the width of the reversible or quantum circuits, moreover, quaternary logic is considered as being a good choice for future quantum computing technology hence it is very suitable for the encoded realization of binary logic functions through its grouping of 2-bits together into quaternary values. The Quaternary decoder, multiplexer, and demultiplexer are essential units of quaternary digital systems. In this paper, we have initially designed a quantum realization of the quaternary decoder circuit using quaternary 1-qudit gates and quaternary Muthukrishnan-Stroud gates. Then we have presented quantum realization of quaternary multiplexer and demultiplexer circuits using the constructed quaternary decoder circuit and quaternary controlled Feynman gates. The suggested circuits in this paper have a lower quantum cost and hardware complexity than the existing designs that are currently used in quaternary digital systems. All the scales applied in this paper are based on Nanometric area.

  12. Augmenting laboratory rearing of stable fly (diptera: muscidae) larvae with ammoniacal salts

    Science.gov (United States)

    Stable flies are serious pests of livestock. The immature stages develop in decaying materials which frequently have high ammonium content. We added various ammonium salts to our laboratory stable fly rearing medium and measured their effect on size and survival as well as the physical properties o...

  13. 75 FR 40729 - Residues of Quaternary Ammonium Compounds, N-Alkyl (C12-14

    Science.gov (United States)

    2010-07-14

    ... ADBAC assessments (as well as the aggregate assessment in the RED) were developed by assuming that an... treated during washing and clothes treated with fabric spray), and humidifiers. The residential handler... ADBAC assessments (as well as the aggregate assessment in the RED) were developed by assuming that an...

  14. Study of cyclic quaternary ammonium bromides by B3LYP calculations, NMR and FTIR spectroscopies.

    Science.gov (United States)

    Brycki, Bogumił; Szulc, Adrianna; Kowalczyk, Iwona

    2010-08-16

    N,N-dioctyl-azepanium, -piperidinium and -pyrrolidinium bromides 1-3, have been obtained and characterized by FTIR and NMR spectroscopy. DFT calculations have also been carried out. The optimized bond lengths, bond angles and torsion angles calculated by B3LYP/6-31G(d,p) approach have been presented. Both FTIR and Raman spectra of 1-3 are consistent with the calculated structures in the gas phase. The screening constants for 13C and 1H atoms have been calculated by the GIAO/B3LYP/6-31G(d,p) approach and analyzed. Linear correlations between the experimental 1H and 13C chemical shifts and the computed screening constants confirm the optimized geometry.

  15. Study of Cyclic Quaternary Ammonium Bromides by B3LYP Calculations, NMR and FTIR Spectroscopies

    Directory of Open Access Journals (Sweden)

    Iwona Kowalczyk

    2010-08-01

    Full Text Available N,N-dioctyl-azepanium, -piperidinium and -pyrrolidinium bromides 1-3, have been obtained and characterized by FTIR and NMR spectroscopy. DFT calculations have also been carried out. The optimized bond lengths, bond angles and torsion angles calculated by B3LYP/6-31G(d,p approach have been presented. Both FTIR and Raman spectra of 1-3 are consistent with the calculated structures in the gas phase. The screening constants for 13C and 1H atoms have been calculated by the GIAO/B3LYP/6-31G(d,p approach and analyzed. Linear correlations between the experimental 1H and 13C chemical shifts and the computed screening constants confirm the optimized geometry.

  16. Studies on extraction of beryllium from thiocyanate solutions by quaternary ammonium halides.

    Science.gov (United States)

    El-Yamani, I S; El-Messieh, E N

    A 0.4M tricaprylmethylammonium chloride solution in n-hexane was used for the quantitative extraction of beryllium from hydrochloric acid (pH 3) and 5M potassium thiocyanate. Beryllium was stripped from the organic phase with 1M sodium hydroxide, then determined volumetrically with bismuthyl perchlorate and bromocresol green indicator. Beryllium was extracted in presence of a large number of elements which are usually associated with it in beryl and in fission products of nuclear fuel.

  17. Synthesis of new antibacterial quaternary ammonium monomer for incorporation into CaP nanocomposite

    NARCIS (Netherlands)

    Zhou, C.; Weir, M.D.; Zhang, K.; Deng, D.; Cheng, L.; Xu, H.H.K.

    2013-01-01

    Objectives Composites are the principal material for tooth cavity restorations due to their esthetics and direct-filling capabilities. However, composites accumulate biofilms in vivo, and secondary caries due to biofilm acids is the main cause of restoration failure. The objectives of this study wer

  18. Synthesis of quaternary ammonium coated surfaces : Physico-chemistry, bacterial killing and phagocytosis

    NARCIS (Netherlands)

    Roest, Steven

    2016-01-01

    The number one cause of failure of biomaterial implants and devices is the occurrence of biomaterial-associated infection. A universal method to create biomaterial implants and devices with intrinsic antimicrobial functionalities is difficult. Immobilizing antimicrobial coatings on existing biomater

  19. Ion Transport Properties of Mechanically Stable symmetric ABCBA Pentablock Copolymers with Quaternary Ammonium Functionalized Midblock

    Energy Technology Data Exchange (ETDEWEB)

    Ertem, S. Piril; Caire, Benjamin R.; Tsai, Tsung-Han; Zeng, Di; Vandiver, Melissa A.; Kusoglu, Ahmet; Seifert, Soenke; Hayward, Ryan C.; Weber, Adam Z.; Herring , Andrew M.; Coughlin, E. Bryan; Liberatore, Matthew W.

    2017-01-01

    Anion exchange membranes (AEMs) are a promising class of materials for applications that require selective ion transport, such as fuel cells, water purification, and electrolysis devices. Studies of structure–morphology–property relationships of ion-exchange membranes revealed that block copolymers exhibit improved ion conductivity and mechanical properties due to their microphase-separated morphologies with well-defined ionic domains. While most studies focused on symmetric diblock or triblock copolymers, here, the first example of a midblock quaternized pentablock AEM is presented. A symmetric ABCBA pentablock copolymer was functionalized to obtain a midblock brominated polymer. Solution cast films were then quaternized to obtain AEMs with resulting ion exchange capacities (IEC) ranging from 0.4 to 0.9 mmol/g. Despite the relatively low IEC, the polymers were highly conductive (up to 60 mS/cm Br2 at 90 8C and 95%RH) with low water absorption (<25 wt %) and maintained adequate mechanical properties in both dry and hydrated conditions. Xray scattering and transmission electron microscopy (TEM) revealed formation of cylindrical non-ionic domains in a connected ionic phase.

  20. Electrochemical membrane reactor: Synthesis of quaternary ammonium hydroxide from its halide by in situ ion substitution

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Mahendra; Tripathi, Bijay P.; Saxena, Arunima [Electro-membrane Processes Division, Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial Research (CSIR), G. B. Marg Bhavnagar 364002 (Gujrat) India (India); Shahi, Vinod K. [Electro-membrane Processes Division, Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial Research (CSIR), G. B. Marg Bhavnagar 364002 (Gujrat) India (India)], E-mail: vkshahi@csmcri.org

    2009-02-01

    Electrochemical membrane reactors (EMRs) with two compartments (EMR-2: anion-exchange membrane (AEM) separated catholyte and anolyte) and three compartments (EMR-3: three compartments separated by two AEMs to avoid contact between the product and the electrodes) were developed for the synthesis of tetrabutylammonium hydroxide (TBAOH) from tetrabutylammonium bromide (TBABr) by in situ ion substitution. In house prepared AEM with good physicochemical, electrochemical properties and excellent stabilities was used. Schematic diagrams are presented for the possible synthesis of TBAOH from TBABr by in situ ion substitution in EMR-2 and EMR-3. Synthesis of TBAOH using EMR-2 and EMR-3 was achieved under different experimental conditions and process parameters (rate of synthesis, current efficiency (CE) and energy consumption) were estimated. In EMR-2, relatively slow synthesis of TBAOH with low recovery was explained due to Hofmann elimination of TBAOH in contact with the electrode. While in EMR-3, relatively faster rate of TBAOH synthesis with its high recovery and current efficiency indicated practical application of the developed process for the efficient synthesis of TBAOH without the use of any additives or reagents.

  1. Quaternary Ammonium Ionic Liquids as a Less Flammable Electrolyte for Lithium Batteries

    Institute of Scientific and Technical Information of China (English)

    H.Matsumoto; Z.B.Zhou; H.Sakaebe; K.Tatsumi

    2007-01-01

    1 Results Less-flammability is one of the most valuable properties of ionic liquids (ILs) comprised of perfluoroanions such as BF-4,TFSI-([(CF3SO2)2N]-).Recently,such a unique liquid has been expected to use as an electrolyte in order to improve thermal stability and longevity of a lithium secondary battery,which have been increasingly required for an application especially to an electric vehicle and a hybrid car.We previously reported that PI13[TFSI] (PI13: N-methyl-N-propylpiperidinium) could be used ...

  2. Investigation on the Extraction Mechanism of Au (I) from Cyanide Solution with Quaternary Ammonium System

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The mechanism of Au (I) extraction has been characterized using 198Au radiometry, thermodynamic equilibrium, Karl-Fischer titration and FT-IR spectroscopy techniques. The results indicate that the extraction follows ionic combination and solvent interaction mechanism. The stoichiometry of the extracted species is 1:1:4:4 for TDMBA+: Au(CN)2- : TBP : H2O. The microstructure model of the extracted complex is a supramolecular structure via hydrogen bonding, ion dipole interaction and ionic combination. The extraction process can be described as micelles in the aqueous phase transfer into the organic phase and reversed micelles or microemulsion (W/O) form in the organic phase.

  3. 40 CFR 721.8658 - Modified polymer of vinyl acetate and quaternary ammonium compound (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Modified polymer of vinyl acetate and... Significant New Uses for Specific Chemical Substances § 721.8658 Modified polymer of vinyl acetate and.... (1) The chemical substance identified generically as modified polymer of vinyl acetate and...

  4. Syntheses of Poly(ethylene oxide) Macromonomers Carrying Tertiary Amine and Quaternary Ammonium End Groups

    National Research Council Canada - National Science Library

    Senyo, Takamichi; Atago, Yuji; Liang, Huanan; Shen, Renhua; Ito, Koichi

    2003-01-01

    p-Vinylbenzyl alcohol, partially alkoxidated with potassium naphthalene, was used successfully to initiate living polymerization of ethylene oxide to afford α-p-vinylbenzyl-ω-hydroxy poly(ethylene oxide) (PEO) macromonomers. The ω...

  5. Cardiovascular Effects and Fatality May Differ According to the Formulation of Glyphosate Salt Herbicide.

    Science.gov (United States)

    Moon, Jeong Mi; Chun, Byeong Jo; Cho, Yong Soo; Lee, Sung Do; Hong, Young Joon; Shin, Min Ho; Jung, Eu Jene; Ryu, Hyun Ho

    2017-06-13

    This study aimed to compare adverse cardiovascular events and fatalities and to identify the risk factors for fatalities associated with the glyphosate salt herbicide formulation. Additionally, we examined whether glyphosate ammonium salt herbicides increased serum ammonia levels. One hundred forty-seven patients were divided into an ammonium group (glyphosate ammonium salt herbicide) and an isopropylamine (IPA) group (glyphosate IPA salt herbicide) according to the type of glyphosate salt formulation ingested. Although no differences in the variables were observed between the groups, the IPA group had more fatalities, a higher incidence of QTc prolongation and a higher tendency for PR prolongation than the ammonium group. Additionally, the IPA group required a longer duration of vasopressor administration. PR prolongation and age were independently associated with fatalities in glyphosate IPA salt poisoning cases in the multivariate regression. Serum ammonia levels were higher at presentation and decreased continuously during the first 48 h after presentation in the ammonium group. This study is the first to suggest potentially different toxicities, especially cardiovascular effects, of glyphosate herbicide poisoning in humans based on the glyphosate salt herbicide formulation and to determine the association between PR prolongation and fatality in glyphosate IPA salt herbicide poisoning cases.

  6. An Electronic Tongue Designed to Detect Ammonium Nitrate in Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Inmaculada Campos

    2013-10-01

    Full Text Available An electronic tongue has been developed to monitor the presence of ammonium nitrate in water. It is based on pulse voltammetry and consists of an array of eight working electrodes (Au; Pt; Rh; Ir; Cu; Co; Ag and Ni encapsulated in a stainless steel cylinder. In a first step the electrochemical response of the different electrodes was studied in the presence of ammonium nitrate in water in order to further design the wave form used in the voltammetric tongue. The response of the electronic tongue was then tested in the presence of a set of 15 common inorganic salts; i.e.; NH4NO3; MgSO4; NH4Cl; NaCl; Na2CO3; (NH42SO4; MgCl2; Na3PO4; K2SO4; K2CO3; CaCl2; NaH2PO4; KCl; NaNO3; K2HPO4. A PCA plot showed a fairly good discrimination between ammonium nitrate and the remaining salts studied. In addition Fuzzy Art map analyses determined that the best classification was obtained using the Pt; Co; Cu and Ni electrodes. Moreover; PLS regression allowed the creation of a model to correlate the voltammetric response of the electrodes with concentrations of ammonium nitrate in the presence of potential interferents such as ammonium chloride and sodium nitrate.

  7. Buried Quaternary Valleys In NW Europe - Aquifers and Drilling Hazards

    Science.gov (United States)

    Huuse, M.; Lykke-Andersen, H.; Piotrowski, J.

    Buried Quaternary valleys are extremely widespread in the formerly glaciated, low- land areas of NW Europe (Huuse &Lykke-Andersen 2000, Fig. 4). The valleys may be several hundred metres deep, some kilometres across and few to several tens of kilometres long. Most of the deep valleys have irregular length profiles with sills and basins, unlike standard subaerial river systems. We interpret these as overdeepened valleys, formed mainly by subglacial meltwater erosion. Buried valleys located on- shore often provide sheltered reservoirs of clean groundwater, and much attention is presently focused on locating onshore valleys and quantifying their potential as groundwater aquifers. In nearshore areas, buried valleys may be a risk factor by pro- viding pathways of salt-water intrusion of onshore groundwater aquifers. Far offshore, buried valleys are located in the shallow subsurface above the prolific oil and gas fields of the central North Sea. Here, the valleys pose a risk for drilling operations by hosting shallow gas and potentially unstable sediments. The central North Sea is now largely covered by 3D seismic data, which often image the buried valleys in a level of de- tail much greater than that available onshore. Hence offshore valleys imaged by 3D seismic data may be used as analogues for groundwater reservoirs onshore NW Eu- rope. Here, we present examples of buried valleys from onshore, nearshore and far offshore locations, to illustrate how genetically and morphologically identical valleys may benefit or hamper the exploitation of subsurface accummulations of groundwater and hydrocarbons. Huuse, M. &Lykke-Andersen, H. 2000. Buried Quaternary valleys in the eastern Dan- ish North Sea: morphology and origin. Quaternary Science Reviews 19, 1233-1253.

  8. Phosphate salts

    Science.gov (United States)

    ... levels that are too high, and for preventing kidney stones. They are also taken for treating osteomalacia (often ... But intravenous phosphate salts should not be used. Kidney stones (nephrolithiasis). Taking potassium phosphate by mouth might help ...

  9. Salt cookbook

    CERN Document Server

    Saha, Anirban

    2015-01-01

    If you are a professional associated with system and infrastructure management, looking at automated infrastructure and deployments, then this book is for you. No prior experience of Salt is required.

  10. Treating ammonium-rich wastewater with sludge from water treatment plant to produce ammonium alum

    Directory of Open Access Journals (Sweden)

    Wen-Po Cheng

    2016-03-01

    Full Text Available This study applies a process to treat ammonium-rich wastewater using alum-generated sludge form water purification plant, and gain economic benefit by producing ammonium alum (Al(NH4(SO42·12H2O. The factors affecting production of ammonium alum include molar ratio of ammonium to aluminum concentration, sulfuric acid concentration, mixing speed, mixing time, standing time, and temperature. According to the equation for the ammonium removal reaction, the theoretical quantity of ammonium alum was calculated based on initial and final concentrations of ammonium. Then, the weight of ammonium alum crystal was divided by the theoretical weight to derive the recovery ratio. The optimum sludge and sulfuric acid dosage to treat about 17 g L−1 ammonium wastewater are 300 g L−1 and 100 mL L−1, respectively. The optimal dosage for wastewater is molar ratio of ammonium to aluminum of about 1 due to the aluminum dissolving in acidified wastewater. The ammonium removal efficiency is roughly 70% and the maximum recovery ratio for ammonium alum is 93% when the wastewater is mixed for 10 min at the mixing velocity gradient of 100 s−1. Ammonium alum production or ammonium removal can be enhanced by controlling the reaction at low temperatures.

  11. Transgenic Arabidopsis expressing osmolyte glycine betaine synthesizing enzymes from halophilic methanogen promote tolerance to drought and salt stress.

    Science.gov (United States)

    Lai, Shu-Jung; Lai, Mei-Chin; Lee, Ren-Jye; Chen, Yu-Hsuan; Yen, Hungchen Emilie

    2014-07-01

    Glycine betaine (betaine) has the highest cellular osmoprotective efficiency which does not accumulate in most glycophytes. The biosynthetic pathway for betaine in higher plants is derived from the oxidation of low-accumulating metabolite choline that limiting the ability of most plants to produce betaine. Halophilic methanoarchaeon Methanohalophilus portucalensis FDF1(T) is a model anaerobic methanogen to study the acclimation of water-deficit stresses which de novo synthesize betaine by the stepwise methylation of glycine, catalyzed by glycine sarcosine N-methyltransferase (GSMT) and sarcosine dimethylglycine N-methyltransferase. In this report, genes encoding these betaine biosynthesizing enzymes, Mpgsmt and Mpsdmt, were introduced into Arabidopsis. The homozygous Mpgsmt (G), Mpsdmt (S), and their cross, Mpgsmt and Mpsdmt (G × S) plants showed increased accumulation of betaine. Water loss from detached leaves was slower in G, S, and G × S lines than wild-type (WT). Pot-grown transgenic plants showed better growth than WT after 9 days of withholding water or irrigating with 300 mM NaCl. G, S, G × S lines also maintained higher relative water content and photosystem II activity than WT under salt stress. This suggests heterologously expressed Mpgsmt and Mpsdmt could enhance tolerance to drought and salt stress in Arabidopsis. We also found a twofold increase in quaternary ammonium compounds in salt-stressed leaves of G lines, presumably due to the activation of GSMT activity by high salinity. This study demonstrates that introducing stress-activated enzymes is a way of avoiding the divergence of primary metabolites under normal growing conditions, while also providing protection in stressful environments.

  12. Preparation of the pyridinium salts differing in the length of the N-alkyl substituent.

    Science.gov (United States)

    Marek, Jan; Stodulka, Petr; Cabal, Jiri; Soukup, Ondrej; Pohanka, Miroslav; Korabecny, Jan; Musilek, Kamil; Kuca, Kamil

    2010-03-19

    Quaternary pyridinium salts with chains ranging from C8 to C20 belong in the large group of cationic surfactants. In this paper, the preparation of such cationic surface active agents based on the pyridinium moiety and differing in the length of the N-alkyl chain is described. Additionally, HPLC technique was established to distinguish each prepared pyridinium analogue. This study represents universal method for preparation and identification of quaternary pyridinium detergents.

  13. Preparation of the Pyridinium Salts Differing in the Length of the N-Alkyl Substituent

    Directory of Open Access Journals (Sweden)

    Kamil Musilek

    2010-03-01

    Full Text Available Quaternary pyridinium salts with chains ranging from C8 to C20 belong in the large group of cationic surfactants. In this paper, the preparation of such cationic surface active agents based on the pyridinium moiety and differing in the length of the N-alkyl chain is described. Additionally, HPLC technique was established to distinguish each prepared pyridinium analogue. This study represents universal method for preparation and identification of quaternary pyridinium detergents.

  14. Influence of Salts on the Partitioning of 5-Hydroxymethylfurfural in Water/MIBK.

    Science.gov (United States)

    Mohammad, Sultan; Held, Christoph; Altuntepe, Emrah; Köse, Tülay; Sadowski, Gabriele

    2016-04-28

    This study investigates the influence of electrolytes on the performance of extracting 5-hydroxymethylfurfural (HMF) from aqueous media using methyl isobutyl ketone (MIBK). For that purpose, liquid-liquid phase equilibria (LLE) of quaternary systems containing HMF, water, MIBK and salts were measured at atmospheric pressure and 298.15 K. The salts under investigation were composed of one of the anions NO(3-), SO4(2-), Cl(-), or CH3COO(-) and of one of the alkali cations Li(+), Na(+), or K(+). On the basis of these LLE data, the partition coefficient of HMF between the aqueous and the MIBK phase KHMF was determined. It could be shown that KHMF significantly depends on the kind and concentration of the added salt. Weak electrolytes (e.g., sulfates, acetates) caused salting-out, whereas nitrates caused salting-in of HMF to the aqueous phase. Unexpectedly, LiCl caused salting-out at low LiCl concentrations and salting-in at LiCl concentrations higher than 3 mol/kgH2O. The model electrolyte perturbed-chain SAFT (ePC-SAFT) was used to predict the salt influence on the LLE in the quaternary systems water/MIBK/HMF/salt in good agreement with the experimental data. On the basis of ePC-SAFT, it could be concluded that the different salting-out/salting-in behavior of the various salts is mainly caused by their different tendency to form ion pairs in aqueous solutions.

  15. Late Quaternary changes in climate

    Energy Technology Data Exchange (ETDEWEB)

    Holmgren, K.; Karlen, W. [Stockholm Univ. (Sweden). Dept. of Physical Geography

    1998-12-01

    This review concerns the Quaternary climate with an emphasis on the last 200 000 years. The present state of art in this field is described and evaluated. The review builds on a thorough examination of classic and recent literature. General as well as detailed patterns in climate are described and the forcing factors and feed-back effects are discussed. Changes in climate occur on all time-scales. During more than 90% of the Quaternary period earth has experienced vast ice sheets, i.e. glaciations have been more normal for the period than the warm interglacial conditions we face today. Major changes in climate, such as the 100 000 years glacial/interglacial cycle, are forced by the Milankovitch three astronomical cycles. Because the cycles have different length climate changes on earth do not follow a simple pattern and it is not possible to find perfect analogues of a certain period in the geological record. Recent discoveries include the observation that major changes in climate seem to occur at the same time on both hemispheres, although the astronomical theory implies a time-lag between latitudes. This probably reflects the influence of feed-back effects within the climate system. Another recent finding of importance is the rapid fluctuations that seem to be a normal process. When earth warmed after the last glaciation temperature jumps of up to 10 deg C occurred within less than a decade and precipitation more than doubled within the same time. The forcing factors behind these rapid fluctuations are not well understood but are believed to be a result of major re-organisations in the oceanic circulation. Realizing that nature, on its own, can cause rapid climate changes of this magnitude put some perspective on the anthropogenic global warming debate, where it is believed that the release of greenhouse gases will result in a global warming of a few C. To understand the forcing behind natural rapid climate changes appears as important as to understand the role

  16. Astronomical Forcing of Salt Marsh Biogeochemical Cascades

    Science.gov (United States)

    Morris, J. T.; Sundberg, K.

    2008-12-01

    Astronomically forced changes in the hydroperiod of a salt marsh affect the rate of marsh primary production leading to a biogeochemical cascade. For example, salt marsh primary production and biogeochemical cycles in coastal salt marshes are sensitive to the 18.6-year lunar nodal cycle, which alters the tidal amplitude by about 5 cm. For marshes that are perched high in the tidal frame, a relatively small increase in tidal amplitude and flooding lowers sediment salinity and stimulates primary production. Porewater sulfide concentrations are positively correlated with tidal amplitude and vary on the same cycle as primary production. Soluble reactive phosphate and ammonium concentrations in pore water also vary on this 18.6- year cycle. Phosphate likely responds to variation in the reaction of sulfide with iron-phosphate compounds, while the production of ammonium in sediments is coupled to the activity of diazotrophs that are carbon- limited and, therefore, are regulated by primary productivity. Ammonium also would accumulate when sulfides block nitrification. These dependencies work as a positive feedback between primary production and nutrient supply and are predictive of the near-term effects of sea-level rise.

  17. 49 CFR 176.410 - Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures. 176.410 Section 176.410 Transportation Other Regulations Relating to... nitrate and ammonium nitrate mixtures. (a) This section prescribes requirements to be observed...

  18. 33 CFR 126.28 - Ammonium nitrate, ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Ammonium nitrate, ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate; general provisions. 126.28 Section 126...) WATERFRONT FACILITIES HANDLING OF DANGEROUS CARGO AT WATERFRONT FACILITIES § 126.28 Ammonium...

  19. Synthesis and application of a quaternary phosphonium polymer coagulant to avoid N-nitrosamine formation.

    Science.gov (United States)

    Zeng, Teng; Pignatello, Joseph J; Li, Russell Jingxian; Mitch, William A

    2014-11-18

    Quaternary ammonium cationic polymers, such as poly(diallyldimethylammonium chloride) (polyDADMAC) are widely used for coagulating and removing negatively charged particles and dissolved organic matter (DOM) from drinking water. Their use, however, has been linked to the formation of carcinogenic N-nitrosamines as byproducts during chloramine-based drinking water disinfection. In this study, a novel quaternary phosphonium cationic polymer, poly(diallyldiethylphosphonium chloride) (polyDADEPC), was synthesized such that the quaternary nitrogen atom of polyDADMAC was substituted with a phosphorus atom. Formation potential tests revealed that even under strong nitrosation conditions, polyDADEPC and related lower-order P-based compounds formed oxygenated and not nitrosated products. Bench-scale jar tests using three different source waters further demonstrated that polyDADEPC achieved coagulation performance comparable to commercial polyDADMACs for particle and DOM removals within the typical dose range used for drinking water treatment. This work highlights the potential use of a phosphonium coagulant polymer, polyDADEPC, as a viable alternative to polyDADMAC to avoid nitrosated byproduct formation during chloramination.

  20. Ammonium hydrogen bis[4-(2-phenyl-2H-tetrazol-5-ylbenzoate

    Directory of Open Access Journals (Sweden)

    Daron E. Janzen

    2016-10-01

    Full Text Available The title salt, NH4+·H+·2C14H9N4O2−, is composed of an ammonium cation with a strong intermolecular negatively charge-assisted hydrogen-bonded acid/conjugate base-pair monoanion. The carboxylic acid H atom is located on an inversion center, while the N atom of the ammonium cation is located on a twofold rotation axis. In the crystal, the N—H bonds of each ammonium cation act as donors with carboxylate O-atom acceptors to form chains along the a-axis direction. The chains are linked by offset π–π interactions [intercentroid distances = 3.588 (2 and 3.686 (2 Å], forming layers parallel to the ab plane.