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Sample records for butylamine

  1. N-butylamine functionalized graphene oxide for detection of iron(III) by photoluminescence quenching.

    Science.gov (United States)

    Gholami, Javad; Manteghian, Mehrdad; Badiei, Alireza; Ueda, Hiroshi; Javanbakht, Mehran

    2016-02-01

    An N-butylamine functionalized graphene oxide nanolayer was synthesized and characterized by ultraviolet (UV)-visible spectrometry, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. Detection of iron(III) based on photoluminescence spectroscopy was investigated. The N-butylamine functionalized graphene oxide was shown to specifically interact with iron (III), compared with other cationic trace elements including potassium (I), sodium (I), calcium (II), chromium (III), zinc (II), cobalt (II), copper (II), magnesium (II), manganese (II), and molybdenum (VI). The quenching effect of iron (III) on the luminescence emission of N-butylamine functionalized graphene oxide layer was used to detect iron (III). The limit of detection (2.8 × 10(-6)  M) and limit of quantitation (2.9 × 10(-5)  M) were obtained under optimal conditions.

  2. Determination of Total Acid in Palygorskite Chemically Modified by N-Butylamine Thermodesorption

    Directory of Open Access Journals (Sweden)

    Ruiz Juan A.C.

    2002-01-01

    Full Text Available The acid properties of palygorskite clay (R1 were studied using n-butylamine as probe molecule. A comparison was made of these properties in palygorskite clay (R1, in an acidified palygorskite (R2 and in acid palygorskite loaded with 2% of lanthanum (R3. The total acid properties were determined by FTIR (Fourier Transform Infrared and TG-DTA (thermogravimetry. The acidity increased as follows: R3>R2>R1. The acid strength sites were classified as physisorbed, weak, medium and strong. The acid treatment did not change the site distribution, apparently only removing channel impurities. The introduction of lanthanum created many more acid sites and increased the specific area. Both weak and strong sites, which increased significantly, were considered new active acid sites produced by the lanthanum.

  3. Synthesis of Nitrogen Incorporated Carbon Nanotubes with Different Diameters by Catalytic Pyrolysis of Butylamine

    Institute of Scientific and Technical Information of China (English)

    JIN Hai-ying; BING Nai-ci; WANG Ling-ling; WANG Li-jun

    2011-01-01

    Bamboo-like nitrogen-doped carbon(CNx)nanotubes were synthesized by chemical vapor deposition (CVD)at a high reaction temperature of 600-900 ℃.The butylamine and Fe/SBA-15 molecular sieve have been used as precursor and catalyst,respectively.Transmission electron microscopy(TEM)and high resolution transmission electron microscopy(HRTEM)observations show that the outer diameter and wall thickness as well as the inner diameter were increased with increasing reaction temperature in a temperature range of 600-800 ℃.A synergism mechanism of the growth through bulk diffusion and the competitive growth through surface diffusion functions during the synthesis of CNx nanotubes was proposed.

  4. Experimental determination of the isothermal (vapour + liquid) equilibria of binary aqueous solutions of sec-butylamine and cyclohexylamine at several temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Chiali-Baba Ahmed, Nouria [LATA2M, Laboratoire de Thermodynamique Appliquee et Modelisation Moleculaire, University AbouBekr Belkaid of Tlemcen, Post Office Box 119, Tlemcen 13000 (Algeria); Negadi, Latifa, E-mail: latifanegadi@yahoo.fr [LATA2M, Laboratoire de Thermodynamique Appliquee et Modelisation Moleculaire, University AbouBekr Belkaid of Tlemcen, Post Office Box 119, Tlemcen 13000 (Algeria); Mokbel, Ilham [LSA, Laboratoire des Sciences Analytiques, CNRS-UMR 5280, Universite Claude Bernard - Lyon I, 43, Bd du 11 Novembre 1918, Villeurbanne Cedex 69622 (France); Kaci, Ahmed Ait [Laboratoire de Thermodynamique et Modelisation Moleculaire, Universite des Sciences et de la Technologie Houari Boumediene, Post Office Box 32, El Alia 16111, Bab Ezzouar (Algeria); Jose, Jacques [LSA, Laboratoire des Sciences Analytiques, CNRS-UMR 5280, Universite Claude Bernard - Lyon I, 43, Bd du 11 Novembre 1918, Villeurbanne Cedex 69622 (France)

    2012-01-15

    Highlights: > Vapour pressures of sec-butylamine or cyclohexylamine and their aqueous solutions. > The investigated temperatures are 273 K and 363 K. > The (cyclohexylamine + water) mixture shows positive azeotropic behaviour. > The (sec-butylamine + water) or (cyclohexylamine + water) exhibit positive G{sup E}. - Abstract: The vapour pressures of (sec-butylamine + water), (cyclohexylamine + water) binary mixtures, and of pure sec-butylamine and cyclohexylamine components were measured by means of two static devices at temperatures between 293 (or 273) K and 363 K. The data were correlated with the Antoine equation. From these data, excess Gibbs functions (G{sup E}) were calculated for several constant temperatures and fitted to a fourth-order Redlich-Kister equation using the Barker's method. The (cyclohexylamine + water) system shows positive azeotropic behaviour for all investigated temperatures. The two binary mixtures exhibit positive deviations in G{sup E} for all investigated temperatures over the whole composition range.

  5. QCM Coated with Self-assembled Cystine-bearing 1,3-Bridged Calix[4]arenes for Recognizing Gas-phase Butylamines

    Institute of Scientific and Technical Information of China (English)

    LI Yuan-Yuan; YIN Hong-Zong; HE Xi-Wen; CHEN Lang-Xing; ZHANG Guo-Zhu; HE Jia-Qi

    2005-01-01

    Two cystine-bearing 1,3-bridged calix[4]arenes were used as the coatings of the quartz crystal microbalance (QCM) with gold electrodes. The two calix[4]arene derivatives were self-assembled onto the gold electrode surface by the covalent attachment between the di-sulfur and gold. The compound of cystine-bearing bi-phenylalanine 1,3-bridged calix[4]arene (CPC) with longer alkyl chain had better self-assembled capacity onto the fresh surfaces of gold electrode than that of cystine-bearing 1,3-bridged calix[4]arene (CC) with comparably shorter alkyl chain.The modified QCM sensors were used to recognize the butylamine isomers in gas. The results showed that the QCM coated with both compounds had preferential affinity to n-butylamine, then i-butylamine, t-butylamine in the range of low concentrations, indicating that in the recognition process, the steric hindrance effect played an important role when forming complex with guest molecules. When the concentrations of the analytes were increased, the polarity and the magnetism of the butylamine became determinative factors. The reversibility was improved greatly and the equilibrium time was much shorter on the self-assembled film than on the film obtained by dropping coating.

  6. Wafer-scale synthesis of thickness-controllable MoS2 films via solution-processing using a dimethylformamide/n-butylamine/2-aminoethanol solvent system.

    Science.gov (United States)

    Yang, Jaehyun; Gu, Yeahyun; Lee, Eunha; Lee, Hyangsook; Park, Sang Han; Cho, Mann-Ho; Kim, Yong Ho; Kim, Yong-Hoon; Kim, Hyoungsub

    2015-05-28

    The wafer-scale synthesis of two-dimensional molybdenum disulfide (MoS2) films, with high layer-controllability and uniformity, remains a significant challenge in the fields of nano and optoelectronics. Here, we report the highly thickness controllable growth of uniform MoS2 thin films on the wafer-scale via a spin-coating route. Formulation of a dimethylformamide-based MoS2 precursor solution mixed with additional amine- and amino alcohol-based solvents (n-butylamine and 2-aminoethanol) allowed for the formation of a uniform coating of MoS2 thin films over a 2 inch wafer-scale SiO2/Si substrate. In addition, facile control of the average number of stacking layers is demonstrated by simply manipulating the concentration of the precursor solution. Various characterization results reveal that the synthesized MoS2 film has wafer-scale homogeneity with excellent crystalline quality and a stoichiometric chemical composition. To further demonstrate possible device applications, a mostly penta-layered MoS2 thin film was integrated into a top-gated field-effect transistor as the channel layer and we also successfully transferred our films onto transparent/flexible substrates.

  7. The influence of conventional heating and microwave irradiation on the resolution of (RS)-sec-butylamine catalyzed by free or immobilized lipases

    Energy Technology Data Exchange (ETDEWEB)

    Pilissao, Cristiane; Nascimento, Maria da Graca, E-mail: maria.nascimento@ufsc.br [Departamento de Quimica, Universidade Federal de Santa Catarina, Florianopolis,SC (Brazil); Carvalho, Patricia de Oliveira [Curso de Farmacia, Universidade Sao Francisco, Braganca Paulista, SP (Brazil)

    2012-09-15

    The lipases CAL-B, PSL, PSL-C, PSL-D, and A. niger lipase, free or immobilized in starch (obtained from two types of yam, known in Brazil as 'cara' (Discorea alata L.) and 'inhame' (Colocasia esculenta (L.) Schott) or gelatin films, were used in the acylation of (RS)-sec-butylamine with different acyl donors in various organic solvents applying conventional heating (CH) or microwave (MW) irradiation. In the case of free A. niger lipase, the conversion degrees were three times higher using MW irradiation when compared to conventional heating at 35 deg C. Using free A. niger lipase, the (R)-amide was obtained with a conversion degree of 21%, resulting in ee{sub p}> 99% and E-value (enantioselectivity value) > 200, in 1 min of reaction under MW irradiation. When the A. niger lipase was immobilized in yam starch films, the (R)-amide was obtained in moderate conversions of 8-25% after 3 or 5 min of reaction under MW irradiation, but with higher selectivity (eep > 99% and E > 200) in comparison with the free form (conversion degree of 45%, eep 81% and E value of 18). (author)

  8. Synthesis, characterization, crystal structure and HSA binding of two new N,O,O-donor Schiff-base ligands derived from dihydroxybenzaldehyde and tert-butylamine

    Science.gov (United States)

    Khosravi, Iman; Hosseini, Farnaz; Khorshidifard, Mahsa; Sahihi, Mehdi; Rudbari, Hadi Amiri

    2016-09-01

    Two new o-hydroxy Schiff-bases compounds, L1 and L2, were derived from the 1:1 M condensation of 2,3-dihydroxybenzaldehyde and 2,4-dihydroxybenzaldehyde with tert-butylamine and were characterized by elemental analysis, FT-IR, 1H and 13C NMR spectroscopies. The crystal structure of L2 was also determined by single crystal X-ray analysis. The crystal structure of L2 showed that the compound exists as a zwitterionic form in the solid state, with the H atom of the phenol group being transferred to the imine N atom. It adopts an E configuration about the central Cdbnd N double bond. Furthermore, binding of these Schiff base ligands to Human Serum Albumin (HSA) was investigated by fluorescence quenching, absorption spectroscopy, molecular docking and molecular dynamics (MD) simulation methods. The fluorescence emission of HSA was quenched by ligands. Also, suitable models were used to analyze the UV-vis absorption spectroscopy data for titration of HSA solution by various amounts of Schiff bases. The spectroscopic studies revealed that these Schiff bases formed 1:1 complex with HSA. Energy transfer mechanism of quenching was discussed and the values of 3.35 and 1.57 nm as the mean distances between the bound ligands and the HSA were calculated for L1 and L2, respectively. Molecular docking results indicated that the main active binding site for these Schiff bases ligands is in subdomain IB. Moreover, MD simulation results suggested that this Schiff base complex can interact with HSA, with a slight modification of its tertiary structure.

  9. Construction of 1D SnO2-coated ZnO nanowire heterojunction for their improved n-butylamine sensing performances

    Science.gov (United States)

    Wang, Liwei; Li, Jintao; Wang, Yinghui; Yu, Kefu; Tang, Xingying; Zhang, Yuanyuan; Wang, Shaopeng; Wei, Chaoshuai

    2016-10-01

    One-dimensional (1D) SnO2-coated ZnO nanowire (SnO2/ZnO NW) N-N heterojunctions were successfully constructed by an effective solvothermal treatment followed with calcination at 400 °C. The obtained samples were characterized by means of XRD, SEM, TEM, Scanning TEM coupled with EDS and XPS analysis, which confirmed that the outer layers of N-type SnO2 nanoparticles (avg. 4 nm) were uniformly distributed onto our pre-synthesized n-type ZnO nanowire supports (diameter 80~100 nm, length 12~16 μm). Comparisons of the gas sensing performances among pure SnO2, pure ZnO NW and the as-fabricated SnO2/ZnO NW heterojunctions revealed that after modification, SnO2/ZnO NW based sensor exhibited remarkably improved response, fast response and recovery speeds, good selectivity and excellent reproducibility to n-butylamine gas, indicating it can be used as promising candidates for high-performance organic amine sensors. The enhanced gas-sensing behavior should be attributed to the unique 1D wire-like morphology of ZnO support, the small size effect of SnO2 nanoparticles, and the semiconductor depletion layer model induced by the strong interfacial interaction between SnO2 and ZnO of the heterojunctions. The as-prepared SnO2/ZnO NW heterojunctions may also supply other novel applications in the fields like photocatalysis, lithium-ion batteries, waste water purification, and so on.

  10. Construction of 1D SnO2-coated ZnO nanowire heterojunction for their improved n-butylamine sensing performances

    Science.gov (United States)

    Wang, Liwei; Li, Jintao; Wang, Yinghui; Yu, Kefu; Tang, Xingying; Zhang, Yuanyuan; Wang, Shaopeng; Wei, Chaoshuai

    2016-01-01

    One-dimensional (1D) SnO2-coated ZnO nanowire (SnO2/ZnO NW) N-N heterojunctions were successfully constructed by an effective solvothermal treatment followed with calcination at 400 °C. The obtained samples were characterized by means of XRD, SEM, TEM, Scanning TEM coupled with EDS and XPS analysis, which confirmed that the outer layers of N-type SnO2 nanoparticles (avg. 4 nm) were uniformly distributed onto our pre-synthesized n-type ZnO nanowire supports (diameter 80~100 nm, length 12~16 μm). Comparisons of the gas sensing performances among pure SnO2, pure ZnO NW and the as-fabricated SnO2/ZnO NW heterojunctions revealed that after modification, SnO2/ZnO NW based sensor exhibited remarkably improved response, fast response and recovery speeds, good selectivity and excellent reproducibility to n-butylamine gas, indicating it can be used as promising candidates for high-performance organic amine sensors. The enhanced gas-sensing behavior should be attributed to the unique 1D wire-like morphology of ZnO support, the small size effect of SnO2 nanoparticles, and the semiconductor depletion layer model induced by the strong interfacial interaction between SnO2 and ZnO of the heterojunctions. The as-prepared SnO2/ZnO NW heterojunctions may also supply other novel applications in the fields like photocatalysis, lithium-ion batteries, waste water purification, and so on. PMID:27734963

  11. Effect of protonation on the isomerization properties of n-butylamine Schiff base of isomeric retinal as revealed by direct HPLC analyses: selection of isomerization pathways by retinal proteins.

    Science.gov (United States)

    Koyama, Y; Kubo, K; Komori, M; Yasuda, H; Mukai, Y

    1991-09-01

    Alumina adsorption chromatography and ion-pair reversed-phase chromatography were developed to analyze the isomers of unprotonated and protonated n-butylamine Schiff base of retinal (RSB and PRSB), respectively. Photoisomerization starting from the all-trans, 11-cis and 13-cis isomers was traced for RSB in n-hexane, acetonitrile, methanol and 1-butanol, and for PRSB in methanol, acetonitrile and 1-butanol. The quantum yields of photoisomerization for the all-trans, 9-cis, 11-cis and 13-cis isomers were determined for RSB and PRSB in the above solvents except 1-butanol. On the other hand, photoisomerization of isomeric retinal bound (through Schiff base linkage) to bovine serum albumin (RBSA) in aqueous solution (pH 3, 7 and 12) as well as thermal isomerization of RSB (in n-hexane), PRSB (in methanol) and RBSA (in aqueous solution, pH 7) were traced starting from the all-trans, 11-cis, and 13-cis isomers. Protonation of RSB drastically changes the pathway of photoisomerization and increases the quantum yields of isomeric RSB. The solvent polarity increases the quantum yields of RSB differently depending on the configuration. Protonation enhances thermal isomerization also. The results of the above model systems are compared with those of retinal proteins to rationalize their selection of the particular isomerization pathways.

  12. Preparation of ASA Emulsions with Butylamine Modified Laponite and Its Sizing Performance%正丁胺改性锂皂石制备ASA Pickering乳液及其施胶性能的研究

    Institute of Scientific and Technical Information of China (English)

    丁鹏翔; 刘温霞

    2011-01-01

    固体微粒稳定的乳液可以避免表面活性剂的不利影响.以纳米尺寸的锂石颗粒为乳化剂,以正丁胺为锂皂石的改性剂,制备了稳定的ASA乳液,并对其施胶性能、水解稳定性进行了研究.结果表明,当水相pH值为6,锂皂石对ASA用量为1.5%,正丁胺对锂皂石用量为2%时,利用改性锂皂石可以制备稳定的ASA乳液.所制备的ASA乳液可以产生良好的施胶效果,但其水解稳定性较差.铝盐的加入可以显著提高ASA乳液的施胶性能,而且在高铝盐添加量下,即使不使用助留剂,ASA乳液也能产生很好的施胶效果.%Solid particles stabilized emulsions can avoid detrimental effects of surfactant. In this paper, ASA emulsions were prepared using nano-size Laponite particles, which were modified by n-butylamine, as emulsifier. Tie sizing performance and hydrolysis stability of the prepared emulsions were investigated. The results showed that stable ASA emulsion is obtained as the pH of aqueous phase, Laponite to ASA mass fraction, bulylamine to Laponite mass fraction are 6.0, 1.5% and 2.0%, respectively. The ASA emulsion shows good sizing performance but low hydrolysis stability. The addition of alum remarkably enhances the sizing efficiency of the ASA emulsion, and with high amount of alum the ASA emulsion can develop a rather high sizing degree for paper even in absence of retention aid.

  13. Effect of Butylamine roxatidine acetate on the apoptosis of ulcer edge mucosal cells in the rats with gastric ulcer%正丁胺基罗沙替丁乙酸酯对大鼠实验性胃溃疡边缘黏膜细胞凋亡的影响

    Institute of Scientific and Technical Information of China (English)

    余秋颖; 李新新; 郝伟; 陈魁敏

    2011-01-01

    OBJECTIVE To observe the effect of Butylamine roxatidine acetate(BRA) on the apoptosis and apoptosis - related gene Bcl -2 protein expression of the mucosal cells in the ulcer border of rats and to investigate the mechanism of the effect of BRA on rat gastric ulcer. METHODS The rat gastric ulcer model was prepared by acetic acid burn and was treated for 15 d with different doses of BRA to observe the apoptosis of ulcer edge mucosal cell and Bcl - 2 expression of apoptosis related genes. RESULTS BRA significantly inhibited gastric mucosal cell apoptosis compared with that of the model group and apoptosis gene Bcl -2 expression was increased significantly at the close of 14,28 mg BRA/kg rat. CONCLUSION Anti - ulcer mechanism of BRA may he related to inhibition of apoptosis and increased Bcl- 2 protein expression.%目的 观察正丁胺基罗沙替丁乙酸酯(BRA)对大鼠实验性胃溃疡边缘黏膜细胞凋亡及凋亡相关基因Bcl-2蛋白表达的影响,探讨其治疗胃溃疡的作用机制.方法 制备大鼠乙酸烧灼型胃溃疡模型,分别给予不同剂量BRA治疗15 d后,观察溃疡边缘黏膜细胞凋亡、凋亡相关基因Bcl-2的表达情况.结果 BRA能显著抑制胃溃疡边缘黏膜细胞凋亡,同时促进凋亡抑制基因Bcl-2的表达,与模型组相比较:14、28 mg·kg-1剂量组的效果更为显著.结论 BRA治疗胃溃疡的作用机制可能与抑制凋亡及增加Bcl-2蛋白表达有关.

  14. Unprecedented Catalytic Wet Oxidation of Glucose to Succinic Acid Induced by the Addition of n-Butylamine to a Ru(III) Catalyst.

    Science.gov (United States)

    Podolean, Iunia; Rizescu, Cristina; Bala, Camelia; Rotariu, Lucian; Parvulescu, Vasile I; Coman, Simona M; Garcia, Hermenegildo

    2016-09-08

    A new pathway for the catalytic wet oxidation (CWO) of glucose is described. Employing a cationic Ru@MNP catalyst, succinic acid is obtained in unprecedently high yield (87.5 %) for a >99.9 % conversion of glucose, most probably through a free radical mechanism combined with catalytic didehydroxylation of vicinal diols and hydrogenation of the resulted unsaturated intermediate.

  15. Field Evaluation of Solvent-Free Sampling with Di-n-butylamine for the Determination of Airborne Monomeric and Oligomeric 1,6-Hexamethylene Diisocyanate

    Science.gov (United States)

    2014-03-27

    in other organ systems . Acute exposure to high levels of HDI vapor has been linked to central nervous system effects including lightheadedness...Species Exposure Duration NOAEL LOAEL LD50 Acute Exposures Rats 6 hr 4-8 hr - 5 ppm 3 ppm 11 ppm 44 ppm - Guinea Pig 2-6 hr 0.5 ppm 1.8 ppm 4...sensitization in guinea pigs , rabbits, and mice. Although dermal absorption is thought to be slow, HDI reacts with the skin proteins to produce a

  16. Effect of Butylamine Roxatidine Acetas on gastric juice excretion in rats with gastric ulcer%正丁胺基罗沙替丁乙酸酯对胃溃疡大鼠胃液分泌的影响

    Institute of Scientific and Technical Information of China (English)

    符文双; 臧晋; 余秋颖

    2009-01-01

    目的:研究正丁胺基罗沙替丁乙酸酯(BRA)对幽门结扎型胃溃疡大鼠胃液成分的影响.方法:采用幽门结扎法制备胃溃疡模型,测定大鼠溃疡指数及胃液分泌量.结果:BRA组溃疡指数、胃液、胃酸分泌量明显降低,胃蛋白酶活性也降低(P<0.01).结论:BRA对实验性胃溃疡有促进溃疡愈合、保护胃黏膜的作用.

  17. 实验研究正丁胺基罗沙替丁乙酸酯治疗胃溃疡%Rats with gastric ulcer were treated by butylamine roxatidine acetas

    Institute of Scientific and Technical Information of China (English)

    陈向华

    2013-01-01

    目的 探讨正丁胺基罗沙替丁乙酸酯(BRA)对胃溃疡大鼠三叶因子2(trefoil factors2,TFF2)、血清脑肠肽(Ghrelin)、生长抑素(somatostatin,SOM)mRNA表达的影响.方法 Wistar大鼠60只随机分为对照组、雷尼替丁组、BRA组.雷尼替丁组、BRA组大鼠造模.对照组予生理盐水灌胃;雷尼替丁组予雷尼替丁灌胃;BRA组以BRA灌胃.ELISA法检测血清TFF2及Ghrelin水平,逆转录PCR(RT-PCR)法检测SOM mRNA的表达.结果 BRA组血清TFF2水平、SOM mRNA显著高于雷尼替丁组;治疗组Ghrelin水平低于雷尼替丁组P均<0.05.结论 BRA可提高胃黏膜组织再生及修复能力,保护胃黏膜促进胃溃疡愈合,为临床应用提供理论依据.

  18. 沙丁胺醇、布地耐德联合吸入治疗小儿毛细支气管炎疗效观察%The sand butylamine mellow,the cloth bears the German union inspiration to treat the young child capillarity bronchitis curative effect observation

    Institute of Scientific and Technical Information of China (English)

    叶红玲

    2010-01-01

    目的:观察沙丁胺醇雾化液与布地奈德混悬液联合雾化吸入治疗毛细支气管炎的疗效.方法:将60例毛细支气管炎患儿随机分为两组,治疗组30例,对照组30例.两组均予常规抗炎、吸氧、止咳、平喘、静脉补液等治疗.治疗组在此基础上加用沙丁胺醇0.03ml/kg+盐水至2ml氧气雾化吸入,间隔4-6小时后布地耐德1ml+盐水1ml氧气雾化吸入,每日二次.结果:治疗组的总有效率为93%,对照组为67%.两组比较差异有显著性(P < 0.05).结论:沙丁胺醇雾化液与布地奈德混悬液联合雾化吸入可尽快缓解喘憋症状,缩短毛细支气管炎的病程及住院时间.

  19. AED8801对小鼠脑缺血的保护作用及对自由基产生的影响%PROTECTION OF 3,4-DICHLOROPHENYL-PROPENOYL-SEC.-BUTYLAMINE AGAINST ANGINST CEREBRAL ISCHEMIA IN MICE AND ITS EFFECTS ON PRODUCTION OF OXYGEN FREE RADICAL IN VITRO

    Institute of Scientific and Technical Information of China (English)

    王迪; 赵艳杰; 陶成

    1999-01-01

    观察3,4-二氯苯丙烯酰另丁胺(AED8801)的脑缺血保护作用及探讨其在自由基方面的作用机制.不完全结扎小鼠双侧颈总动脉及双侧迷走神经引起小鼠脑缺血,观察缺血后6小时卒中指数、12小时存活时间及其死亡率;体外生成·OH和O-2.3,4-二氯苯丙烯酰另丁胺50,100和150mg.kg-1ip.可降低缺血小鼠的卒中指数、延长存活时间和降低死亡率,且呈一定的剂量依赖性,具有一定的脑缺血保护作用.体外实验表明,3,4-二氯苯丙烯酰另丁胺10-7~10-4mol. L-1对体外生成的·OH具有明显的清除作用;10-6~10-3mo1.L-1对体外生成的O2亦有一定的抑制作用.3,4-二氯苯丙烯酰另丁胺对脑缺血的保护作用可能与其对自由基的影响有关.

  20. 正丁胺罗沙替丁乙酸酯对动物实验性胃溃疡及急性毒性实验的影响%Effect of Butylamine Roxatidine Acetas on Experimental Gastric Ulcer and Its Acute Toxicity

    Institute of Scientific and Technical Information of China (English)

    余秋颖; 王媛; 郝伟

    2009-01-01

    目的 研究正丁胺基罗沙替丁乙酸酯(BRA)对动物实验性胃溃疡的影响.方法 应用大鼠醋酸烧灼法、幽门结扎法和小鼠水浸应激法制备胃溃疡模型,测定大鼠溃疡指数、溃疡抑制率,胃液分泌量,急性毒性实验测半数致死量.结果 BRA组溃疡指数、胃液、胃酸分泌量明显降低,减少胃蛋白酶活性.LD50=663.64mg·kg-1.结论 BRA对实验性胃溃疡有促进溃疡愈合,保护胃黏膜的作用.

  1. Influence of butylamine roxatidine acetate on seroactive fractions in rats with gastric ulcer%正丁胺基罗沙替丁乙酸脂对胃溃疡大鼠胃黏膜活性因子的影响

    Institute of Scientific and Technical Information of China (English)

    江敏; 张量; 余秋颖

    2009-01-01

    目的:观察BRA对乙酸烧灼型溃疡大鼠胃黏膜中活性成分的影响,探讨该药对实验性溃疡大鼠溃疡愈合的治疗作用.方法:采用冰醋酸烧灼法制备胃溃疡模型,连续药物治疗15 d后取血,生化指标检测NO、MD、SOD含量.结果:BRA各剂量组均能使胃黏膜NO含量升高;并提高胃黏膜SOD的含量,降低MDA水平,与模型对照组比较,差异有统计学意义(P<0.01).结论:BRA通过提高胃黏膜NO、SOD含量、降低MDA含量,减少溃疡黏膜损伤,促进溃疡愈合,对实验性胃溃疡有保护性治疗作用.

  2. Spectrophotometric Study of Adduct Formation Between [Co(Salen)PPh3]ClO4.H2O and [Co(7,7'-Dimethylsalen)PPh3]ClO4.H2O with Amines Donors in Acetonitrile

    OpenAIRE

    2010-01-01

    The equilibrium quotient of the adduct formation of [Co(Salen)PPh3]ClO4.H2O and [Co(7,7'-dimethylSalen)PPh3]ClO4.H2O, as acceptor with amines donors are studied by spectrophotometer. Thermodynamics of these pentacoordinate cobalt(III) Schiff-base complexes have been examined with n-butylamine, sec-butylamine, tert-butylamine, benzylamine and diethylamine in constant ionic strength of 0.1 M sodium perchlorate and acetonitrile solvent at room temperature. We aimed to investigate the effects of ...

  3. Preintercalation of Layered γ-Zirconium Phosphate for Preparation of Immobilized Hemoglobin

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Layeredγ-Zirconium phosphate (γ-ZrP) preintercalated with butylamine, tetra (n-butylammonium)hydroxide, dimethylamine respectively, or only ultrasonificated, for preparation of immobilized hemoglobin were investigated in this report.

  4. Fundamental Studies in the Molecular Basis of Laser Induced Retinal Damage

    Science.gov (United States)

    1988-01-01

    paper we apply SHG to compare the second harmonic properties of monolayers of retinal, retinylidene n-butylamine Schiff base (NRB) and protonated NRB...retinylidene butylamine Schiff base (NRB) was prepared as described before’. The molar concentrations of retinal, unprotonated and protonated NRB in...addition, the proton on the Schiff base notrogen of protonated NRB was found to be able to detach from the nitrogen. In order to avoid these problems, the

  5. Volumetric Properties of Chloroalkanes + Amines Mixtures: Theoretical Analysis Using the ERAS-Model

    Science.gov (United States)

    Tôrres, R. B.; Hoga, H. E.; Magalhães, J. G.; Volpe, P. L. O.

    2009-08-01

    In this study, experimental data of excess molar volumes of {dichloromethane (DCM), or trichloromethane (TCM) + n-butylamine (n-BA), or +s-butylamine (s-BA), or +t-butylamine (t-BA), or +diethylamine (DEA), or +triethylamine (TEA)} mixtures as a function of composition have been used to test the applicability of the extended real associated solution model (ERAS-Model). The values of the excess molar volume were negative for (DCM + t-BA, or +DEA, or +TEA and TCM + n-BA, or +s-BA, or +DEA, or +TEA) mixtures and present sigmoid curves for (DCM + n-BA, or +s-BA) mixtures over the complete mole-fraction range. The agreement between theoretical and experimental results is discussed in terms of cross-association between the components present in the mixtures.

  6. Symmetrical and Unsymmetrical Schiff Bases Derived from 3,4-Diaminobenzophenone: Synthesis and Thermodynamics of Five Coordinated Tertiaryphosphine Cobalt(III Complexes

    Directory of Open Access Journals (Sweden)

    Khosro Mohammadi

    2016-09-01

    Full Text Available Some new cobalt(III complexes described as [Co(Chel(PBu3]ClO4 × H2O where (Chel is the deprotonated form of a series of symmetric and unsymmetrical Schiff base ligands containing 3,4-diaminobenzophenone (3,4-DABP and substituted salicylaldehyde moieties and [Co(Chel(PMePh2]ClO4 × H2O where (Chel is [N’-(5-BrSalDABP] were synthesized and characterized by 1H NMR, IR, UV–Vis spectroscopy, and elemental analysis. The formation constants and the thermodynamic parameters were determined spectrophotometrically for 1: 1 adduct formation of the new complexes as acceptor with some aliphatic amines such as benzylamine, n-butylamine, sec-butylamine and tert-butylamine as donors in DMSO solvent in constant ionic strength (I = 0.1 M NaClO4. The formation constants change according to the following trend due to the steric and the electronic factors of the cobalt(III complexes: N’-5-OMe > N’-5-H > N’-5-Br > N’-5-Cl; N,N’-3-OMe > N,N’-4-Ome. The trend of the formation constants of cobalt(III Schiff base complexes toward a given donor according to the axial ligand is as follow: PBu3 > PMePh2. Also, the following binding trend of the donors toward a given cobalt(III Schiff base complex is obtained: benzylamine > n-butylamine > sec-butylamine > tert-butylamine. This work is licensed under a Creative Commons Attribution 4.0 International License.

  7. Fabrication of patterned mirror modules for generating laser line beams

    Science.gov (United States)

    Lee, Changyun; Kim, Taeggyum; Hong, Sangsu; Kim, Baekyun

    2008-02-01

    A method for fabricating Ag coated beam splitter is reported. This is showing specific patterned transmittance by immersing glass substrates in the mixture of H IISO 4 and H IIO II to make negatively charged oxygen sites at silica surface and then in ethanolic solutions of AgNO 3 and butylamine. We controlled the soaking time and molar ratios of the mixture of AgNO 3 and butylamine to pattern % transmittance of electroless coated glass surface. Finally, we made a functionalized beam splitters showing step function like transmittance and applied this to make multiple laser beams for display and laser machining.

  8. Preparation of lamellar compounds: synthesis of the crystalline zirconium hydrogenphosphate and its intercalation with amines. An experiment for undergraduate students; Preparacao de compostos lamelares: sintese do hidrogenofosfato de zirconio cristalino e sua intercalacao com aminas. Um experimento para estudantes de graduacao

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, William da Silva; Gushikem, Yoshitaka [Universidade Estadual de Campinas, SP (Brazil). Inst. de Quimica]. E-mail: gushikem@iqm.unicamp.br

    2005-07-15

    The present paper describes the synthesis of crystalline zirconium hydrogen phosphate by direct precipitation and its intercalation with pyridine and n-butylamine. The simple experiment was tested in the undergraduate inorganic chemistry laboratory course for chemistry students at IQ-UNICAMP using inexpensive reagents. The materials were characterized by powder X-ray diffraction and infrared analyses in order to obtain detailed information of the solid structure changes as a result of the intercalation process. Pyridine and n-butylamine are focused in this work as clear and elucidative examples leading to acid-base interactive processes that result in the well-formed infinite sequence of inorganic lamellar structures. (author)

  9. Short Synthesis of C-terminal Modified Peptides by a Series-connection Procedure

    Institute of Scientific and Technical Information of China (English)

    Gui Jie TIAN; Chuan Liang QIU; Zhe LIU; De Xin WANG

    2005-01-01

    Three peptide alcohols and four peptidyl N-akyl-amides were prepared by a series-connection procedure consisting of n-1 sequencial assembly on solid support followed by ammonolysis with glycinol, benzylamine or n-butylamine, and successive extractionelution through C-18 layer. All products were obtained from this procedure without further purification,in an overall yield of 75-86%.

  10. Validation of transferability of DBA derivatization and LC-MS/MS determination method for isocyanates via an interlaboratory comparison

    NARCIS (Netherlands)

    Bobeldijk, I.; Karlsson, D.; Pronk, A.; Gonsalves, J.; Hekman, M.; Lagemaat, D. van de; Preller, L.; Heederik, D.; Skarping, G.

    2008-01-01

    An adapted method for the quantitative determination of isocyanates in air was implemented and validated in-house. The method was based on air sampling using an impinger flask containing di-n-butylamine (DBA) in toluene and a glass fibre filter in series. The DBA derivatives were determined using li

  11. Odour sensitivity of antennal olfactory cells underlying grooved pegs of Anopheles gambiae s.s. and An. quadriannulatus

    NARCIS (Netherlands)

    van den Broek, IVF; den Otter, CJ

    2000-01-01

    In female mosquitoes of the anthropophilic species Anopheles gambiae Giles s.s. and the zoophilic An. quadriannulatus Theobald single sensillum recordings from grooved pegs were made. In both species, the majority of these sensilla responded to ammonium hydroxide, butylamine and propanoic acid, wher

  12. Epoxidation reaction of perfluoroalkenes with tert-amine N-oxide

    Institute of Scientific and Technical Information of China (English)

    Xing Wei Cai; Min Sha; Biao Jiang; Ren Ming Pan

    2012-01-01

    Straight-chain aliphatic tert-amine N-oxides were found to be useful oxidizing agent for epoxidation of tri-and tetra-substituted perfluoroalkenes under mild conditions in high yields.The process for epoxidation by employing tri-n-butylamine N-oxide gave the best result in the reagent survey.

  13. Preparation and permeability of ZSM-35 zeolite membranes on porous stainless steel tubes

    Institute of Scientific and Technical Information of China (English)

    ZHU Gang; WANG Jinqu; ZHANG Yan; LU Jinming; XIU Jinghai

    2007-01-01

    ZSM-35 zeolite membranes were prepared on porous stainless steel tubes with silica sol and tetraethoxysilane as silica source,and with 1-butylamine and ethylenediamine as templates,respectively.The characterization of X-ray diffraction(XRD)and scanning electron microscopy (SEM)showed that the membranes prepared with ethylene-diamine as the template displayed growth orientation with their crystal planes(h00)parallel to the support surface.The single-component permeability tests of H2,N2 and C3H8 showed that me membranes synthesized with ethylene-diamine as the template,compared with those witb 1-butylamine as the template,showed relatively higher permeation rates and ideal separation factors,and above their corresponding ideal Knudsen diflusion factors,Which might be attributed to the different growth orientation of zeolite membranes synthesized with different templates.

  14. Kinetics of proton transfer from tetra( m-trifluoromethylphenyl)dibenzotetraazaporphin to nitrogen-containing bases in a benzene-dimethyl sulfoxide system

    Science.gov (United States)

    Petrov, O. A.

    2015-02-01

    The acid-base interaction between tetra( m-trifluoromethylphenyl)dibenzotetraazaporphin with pyridine, 2-methylpyridine, morpholine, piperidine, n-butylamine, diethylamine, and triethylamine is studied in the benzene-dimethyl sulfoxide system. It is found that intermolecular transfer of protons of NH-groups from of tetra( m-trifluoromethylphenyl)dibenzotetraazaporphin to n-butylamine and piperidine is characterized by unusually low values of the rate constants. The effect the structure of tetra( m-trifluoromethylphenyl)dibenzotetraazaporphin, hexa( m-trifluoromethylphenyl)benzotetraazaporphin, and octa( m-trifluoromethylphenyl)tetraazaporphin has on the kinetic parameters of acid-base interaction is demonstrated, along with that of the nature of the base and solvent. A structure is proposed for the charge-transfer complexes of the substituted tetraazaporphyrins. It is found that they undergo destruction over time.

  15. A kinetic study of guest displacement reactions on a host-guest complex with a photoswitchable calixarene.

    Science.gov (United States)

    Letzel, Matthias C; Schäfer, Christian; Novara, Francesca R; Speranza, Maurizio; Rozhenko, Alexander B; Schoeller, Wolfgang W; Mattay, Jochen

    2008-11-01

    The displacement processes of several guests, incorporated in a calixarene host system, were investigated in the gas phase by electrospray ionization-Fourier transform-ion cyclotron resonance (ESI-FT-ICR) mass spectrometry. The complexes resulting from a resorcin[4]arene host with ammonia and sec-butylamine guests were isolated in an ICR-cell, separately using both states of the photoswitch as well as two reference systems for the open and closed forms of the photoswitchable host. The isolated complexes were forced to exchange the guest by using methylamine, ethylamine and sec-butylamine, resulting in different reaction rates for all the measured systems. Especially, the reaction rates of both states of the photoswitch are dependent on the provided guest. Potential side effects like proton exchanges were examined by an H/D-exchange experiment. The results were investigated and supported by quantum chemical calculations (DFT).

  16. Study on Solution Properties of Binary Mixtures of Some Industrially Important Solvents with Cyclohexylamine and Cyclohexanone at 298.15 K

    Science.gov (United States)

    Roy, Mahendra Nath; Das, Rajesh Kumar; Chanda, Riju

    2010-03-01

    Densities and viscosities were measured for the binary mixtures of cyclohexylamine and cyclohexanone with butyl acetate, butanone, butylamine, tert-butylamine, and 2-butoxyethanol at 298.15 K over the entire composition range. From density data, the values of the excess molar volume ( V E) have been calculated. The experimental viscosity data were correlated by means of the equation of Grunberg-Nissan. The density and viscosity data have been analyzed in terms of some semiempirical viscosity models. The results are discussed in terms of molecular interactions and structural effects. The excess molar volume is found to be either negative or positive depending on the molecular interactions and the nature of the liquid mixtures and is discussed in terms of molecular interactions and structural changes.

  17. Photocatalytic treatment of municipal wastewater using modified neodymium doped TiO(2) hybrid nanoparticles.

    Science.gov (United States)

    Shahmoradi, Behzad; Ibrahim, Ibrahim A; Sakamoto, Naonori; Ananda, Sannaiah; Somashekar, Rudrappa; Row, Tagur N Guru; Byrappa, Kullaiah

    2010-08-01

    Photocatalytic degradation of municipal wastewater was investigated using reagent grade TiO(2) and modified neodymium doped TiO(2) hybrid nanoparticles. For the first time, surface modification of Nd(3 +) doped TiO(2) hybrid nanoparticles were carried out with n-butylamine as surface modifier under mild hydrothermal conditions. The modified nanoparticles obtained were characterized by Powder XRD, FTIR, DLS, TEM, BET surface area, zeta potential and UV-Vis Spectroscopy. The characterization results indicated better morphology, particle size distribution and low agglomeration of the nanoparticles synthesized. It was found that photodegradation of wastewater using surface modified neodymium doped TiO(2) nanoparticles was more compared to pure TiO(2), which can be attributed to the doping and modification with n-butylamine.

  18. Halloysite nanotube supported Ag nanoparticles heteroarchitectures as catalysts for polymerization of alkylsilanes to superhydrophobic silanol/siloxane composite microspheres.

    Science.gov (United States)

    Li, Cuiping; Li, Xueyuan; Duan, Xuelan; Li, Guangjie; Wang, Jiaqiang

    2014-12-15

    Halloysite nanotube supported Ag nanoparticles heteroarchitectures have been prepared through a very simple electroless plating method. Robust Ag nanocrystals can be reproducibly fabricated by soaking halloysite nanotubes in ethanolic solutions of AgNO3 and butylamine. By simply adjusting the molar ratio of AgNO3 and butylamine, Ag nanoparticles with tunable size and quantity on halloysite nanotube are achieved. It reveals that the Ag nanoparticles are well-dispersed on the surface of halloysite nanotubes. The halloysite nanotube supported Ag nanoparticles heteroarchitectures can serve as active catalysts for the polymerization of an alkylsilane C18H37SiH3 with water to form silanol/siloxane composite microspheres and exhibit interesting superhydrophobicity ascribed to the micro/nanobinary structure.

  19. Evidence for covalent binding of epicocconone with proteins from synchronous fluorescence spectra and fluorescence lifetimes

    Indian Academy of Sciences (India)

    Debashis Panda; Anindya Datta

    2007-03-01

    Synchronous fluorescence and time-resolved fluorescence spectroscopic studies that reveal the interaction of epicocconone with human serum albumin is significantly different from its interaction with surfactant assemblies. This observation, along with steady-state fluorescence data, indicates groundstate interaction between the fluorophore epicocconone and the protein. Similarity in fluorescence properties with the adduct of the fluorophore with -butylamine indicates that bonding occurs at the Nterminus of the protein.

  20. Study on Synthesis and Intercalation Behavior of Layered Zirconium Proline-N-methylphosphonate-phosphate

    Institute of Scientific and Technical Information of China (English)

    Xiao Ping RAO; Xiang Kai FU; Kai RAO

    2004-01-01

    Zirconium proline-N-methylphosphonate-phosphate (α-ZPMPP) was prepared in the presence of HF for the first time. The α-ZPMPP sample is highly crystallized with interlayer distance of 1.52 nm. The interlayer distance of complex of α-ZPMPP with n-butylamine (α-ZPMPP-BA) is in 0.45 nm larger than that of α-ZPMPP. The α-ZPMPP possesses different intercalation behavior of host-guest compound from α-ZP.

  1. Environmental Compliance Assessment Army Reserve (ECAAR)

    Science.gov (United States)

    1993-09-01

    manufacturing processes: electric power generation; fertilizer/agricultural chemicals; food and related products/by- products; inorganic chemicals; iron and...2,3-cd)pyrene 100 U137 193-39-5 Iron , pentacarbonyl- 100 13463-40-06 iso-Arnyl acetate 5000 123-92-2 iso-Butyl acetate 5000 110-19-0 iso-Butylamine 1000...polystachion (Linnaeus) Schultes missiongrass, thin napiergrass Prosopis alpalaco R.A.Philippi Prosopis argentina Burkart Prosopis articulata

  2. 棉籽油脂肪酸正丁基酰胺的合成及表征%Synthesis and Characterization of Cottonseed Oil Fatty Acid Butylamide

    Institute of Scientific and Technical Information of China (English)

    陈玉成; 陈炜; 侯桂锋; 陈青青; 范培珠

    2012-01-01

    Fatty acid butylamide was synthesized with fatty acid from cottonseed oil and butylamine used as raw materials in this article. Synthetic conditions of fatty acid butylamide were researched through orthogonal experiment. The optimum technological conditions were as following: reaction temperature 125 ~C, reaction time 3.0 h, amount of catalyst 1.5%, molar ratio of fatty acid and butylamine 10: 7. Conversion rate of butylamine can reach 92.45% under optimum conditions. The'structure of product was confirmed by Fourier transform infrared spectrometer(FTIR) for identifvin~ the product as the taruet object.%以棉籽油脂肪酸和正丁胺为原料合成了棉籽油脂肪酸正丁基酰胺.通过正交试验,确定其合成的最佳工艺条件:反应温度为125℃、反应时间为3.0h、催化荆用量为1.5%、投料比(棉籽油脂肪酸与正丁胺摩尔比)10:7.在优化反应条件下正丁胺的转化率达92.45%,通过红外光谱进行结构表征,确定反应产物为目标产物.

  3. The effect of acidic and basic additives on the enantioseparation of basic drugs using polysaccharide-based chiral stationary phases.

    Science.gov (United States)

    Ye, Yun K; Stringham, Rodger W

    2006-08-01

    The enantioseparation of nine commercially available basic drugs was achieved on polysaccharide-based chiral stationary phases with the acidic additive ethanesulfonic acid and the basic additive butylamine. Seven different commercially available CSPs were used for the study (AD, AS, OD, OJ, OG, OB, and OC). Mobile phase additives have been proven to be essential in obtaining satisfactory enantio-resolution in terms of both efficiency and selectivity. Significantly improved selectivities were obtained for the basic probe drugs with the acidic additive, ethanesulfonic acid, rather than the basic additive, butylamine. This is best seen with Chiralpak AS CSP. No enantioseparation for the nine drugs was observed when butylamine was used as an additive; however, satisfactory enantioseparation for the nine drugs was achieved using ethanesulfonic acid. Higher column efficiencies were observed with the acidic additive, especially when isopropanol was used as a modifier. Higher sensitivity was also achieved with ethanesulfonic acid because of the significantly lower background at the UV detection wavelength. The acidic additive was demonstrated to be superior to the basic additive for the enantioseparation of basic drugs using seven different polysaccharide-based CSPs. These results are counterintuitive to the common "rule of thumb" in enantioseparation that states acidic additives work best for acidic analytes and basic additives work best for basic analytes. The beneficial effects of acidic additive in enantioseparations observed in this study could significantly improve the applicability of polysaccharide-based CSPs for the enantioseparation of basic analytes.

  4. Electrochemical Characterization of Protein Adsorption onto YNGRT-Au and VLGXE-Au Surfaces

    Directory of Open Access Journals (Sweden)

    Hanna Trzeciakiewicz

    2015-08-01

    Full Text Available The adsorption of the proteins CD13, mucin and bovine serum albumin on VLGXE-Au and YNGRT-Au interfaces was monitored by electrochemical impedance spectroscopy in the presence of [Fe(CN6]3−/4−. The hydrophobicity of the Au surface was tailored using specific peptides, blocking agents and diluents. The combination of blocking agents (ethanolamine or n-butylamine and diluents (hexanethiol or 2-mercaptoethanol was used to prepare various peptide-modified Au surfaces. Protein adsorption onto the peptide-Au surfaces modified with the combination of n-butylamine and hexanethiol produced a dramatic decrease in the charge transfer resistance, Rct, for all three proteins. In contrast, polar peptide-surfaces induced a minimal change in Rct for all three proteins. Furthermore, an increase in Rct was observed with CD13 (an aminopeptidase overexpressed in certain cancers in comparison to the other proteins when the VLGXE-Au surface was modified with n-butylamine as a blocking agent. The electrochemical data indicated that protein adsorption may be modulated by tailoring the peptide sequence on Au surfaces and that blocking agents and diluents play a key role in promoting or preventing protein adsorption. The peptide-Au platform may also be used for targeting cancer biomarkers with designer peptides.

  5. Si{endash}N linkage in ultrabright, ultrasmall Si nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Rogozhina, E.; Belomoin, G.; Smith, A.; Abuhassan, L.; Barry, N.; Akcakir, O.; Braun, P. V.; Nayfeh, M. H.

    2001-06-04

    Ultrabright ultrasmall ({similar_to}1 nm) blue luminescent Si{sub 29} nanoparticles are chlorinated by reaction with Cl{sub 2} gas. A Si{endash}N linkage is formed by the reaction of the chlorinated particles with the functional amine group in butylamine. Fourier transform infrared spectroscopy and x-ray photospectroscopy measurements confirm the N linkage and the presence of the butyl group, while emission, excitation, and autocorrelation femtosecond optical spectroscopy show that, after the linkage formation, the particles with the ultrabright blue luminescent remain, but with a redshift of 40 nm. {copyright} 2001 American Institute of Physics.

  6. Deriving static atomic multipoles from the electrostatic potential.

    Science.gov (United States)

    Kramer, Christian; Bereau, Tristan; Spinn, Alexander; Liedl, Klaus R; Gedeck, Peter; Meuwly, Markus

    2013-12-23

    The description of molecular systems using multipolar electrostatics calls for automated methods to fit the necessary parameters. In this paper, we describe an open-source software package that allows fitting atomic multipoles (MTPs) from the ab initio electrostatic potential by adequate atom typing and judicious assignment of the local axis system. By enabling the simultaneous fit of several molecules and/or conformations, the package addresses issues of parameter transferability and lack of sampling for buried atoms. We illustrate the method by studying a series of small alcohol molecules, as well as various conformations of protonated butylamine.

  7. Time-resolved energy transfer from single chloride terminated nanocrystals to graphene

    CERN Document Server

    Ajayi, O A; Cotlet, M; Petrone, N; Gu, T; Wolcott, A; Gesuele, F; Hone, J; Owen, J S; Wong, C W

    2014-01-01

    We examine the time-resolved resonance energy transfer of excitons from single n-butyl amine-bound, chloride-terminated nanocrystals to two-dimensional graphene through time-correlated single photon counting. The radiative biexponential lifetime kinetics and blinking statistics of the individual surface-modified nanocrystal elucidate the non-radiative decay channels. Blinking modification as well as a 4 times reduction in spontaneous emission were observed with the short chloride and n-butylamine ligands, probing the energy transfer pathways for the development of graphene-nanocrystal nanophotonic devices.

  8. Preparation of porous lanthanum phosphate with templates

    Energy Technology Data Exchange (ETDEWEB)

    Onoda, Hiroaki, E-mail: onoda@kpu.ac.jp [Department of Informatics and Environmental Sciences, Faculty of Life and Environmental Sciences, Kyoto Prefectural University, 1-5, Shimogamo Nakaragi-cyo, Sakyo-ku, Kyoto 606-8522 (Japan); Ishima, Yuya [Department of Applied Chemistry, Faculty of Life Sciences, Ritsumeikan University, 1-1-1, Nojihigashi, Kusatsu, Shiga 525-8577 (Japan); Takenaka, Atsushi [Department of Materials Science, Yonago National College of Technology, 4448, Hikona-cho, Yonago, Tottori 683-8502 (Japan); Tanaka, Isao [Department of Materials Science and Engineering, Faculty of Engineering, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan)

    2009-08-05

    Malonic acid, propionic acid, glycine, n-butylamine, and urea were added to the preparation of lanthanum phosphate from lanthanum nitrate and phosphoric acid solutions. All additives were taken into lanthanum phosphate particles. The additives that have a basic site were easy to contain in precipitates. The addition of templates improved the specific surface area of lanthanum phosphate. The amount of pore, with radius smaller than 4 nm, increased with the addition of templates. The remained additives had influence on the acidic properties of lanthanum phosphate.

  9. Secondary organic aerosol formation from primary aliphatic amines with NO3 radical

    Directory of Open Access Journals (Sweden)

    M. E. Erupe

    2008-07-01

    Full Text Available Primary aliphatic amines are an important class of nitrogen containing compounds found to be emitted from automobiles, waste treatment facilities and agricultural animal operations. A series of experiments conducted at the UC-Riverside/CE-CERT Environmental Chamber is presented in which oxidation of methylamine, ethylamine, propylamine, and butylamine with NO3 has been investigated. Very little aerosol formation is observed in the presence of O3 only. However, after addition of NO, and by extension NO3, large yields of aerosol mass loadings (~44% for butylamine are seen. Aerosol generated was determined to be organic in nature due to the small fraction of NO and NO2 in the total signal (<17% for all amines tested as detected by an aerosol mass spectrometer (AMS. We propose a reaction mechanism between carbonyl containing species and the parent amine leading to formation of particulate imine products. These findings can have significant impacts on rural communities and lead to elevated nighttime PM loadings, when significant levels on NO3 exist.

  10. Synthesis and Characterization of Cottonseed Oil Fatty Acid Butylamide%DM6446平台下车道线检测系统设计与实现

    Institute of Scientific and Technical Information of China (English)

    王晓栋; 严菲; 许华荣

    2012-01-01

    为了克服传统的“驾驶员一汽车一道路”闭环汽车驾驶模式中存在的缺点,提高车辆行驶安全,提出一种基于ARM+DSP架构的嵌入式实时车道线检测系统。介绍该系统的总体架构和异构双核处理器的数据处理流程及系统核心算法的实现和优化方法.同时提出了针对DM6446异构双核开发平台的系统实现方案,并通过实验验证了系统的有效性.%Fatty acid butylamide was synthesized with fatty acid from cottonseed oil and butylamine used as raw materials in this article. Synthetic conditions of fatty acid butylamide were researched through orthogonal experiment. The optimum technological conditions were as following: reaction temperature 125 ~C, reaction time 3.0 h, amount of catalyst 1.5%, molar ratio of fatty acid and butylamine 10: 7. Conversion rate of hutylamine can reach 92.45% under optimum conditions. The'structure of product was confirmed by Fourier transform infrared spectrometer( FrIR/for identifying, th ,~ I. L..__.

  11. Volumetric behaviour of binary mixtures of (trichloromethane + amines) at temperatures between T = (288.15 and 303.15) K at p = 0.1 MPa

    Energy Technology Data Exchange (ETDEWEB)

    Magalhaes, J.G. [Departamento de Fisico-Quimica, Instituto de Quimica, Universidade Estadual de Campinas, UNICAMP, C.P. 6145, 13083-970 Campinas, Sao Paulo (Brazil); Torres, R.B. [Departamento de Fisico-Quimica, Instituto de Quimica, Universidade Estadual de Campinas, UNICAMP, C.P. 6145, 13083-970 Campinas, Sao Paulo (Brazil); Departamento de Engenharia Quimica, Centro Universitario da FEI, 09850-901 Sao Bernardo do Campo, Sao Paulo (Brazil)], E-mail: belchior@fei.edu.br; Volpe, P.L.O. [Departamento de Fisico-Quimica, Instituto de Quimica, Universidade Estadual de Campinas, UNICAMP, C.P. 6145, 13083-970 Campinas, Sao Paulo (Brazil)

    2008-09-15

    In this work, densities of binary mixtures of {l_brace}trichloromethane (TCM) + n-butylamine (n-BA), or + s-butylamine (s-BA), or + diethylamine (DEA), or + triethylamine (TEA){r_brace} have been determined under atmospheric pressure as a function of composition and temperature using a vibrating-tube densimeter. The temperatures studied were T = (288.15, 293.15, 298.15, and 303.15) K. The excess molar volumes (V{sub m}{sup E}), calculated from density data are negative for all studied systems and the negative deviations follow the sequence: TEA > DEA > s-BA > n-BA. Negative values of V{sub m}{sup E} for binary mixtures were attributed to the formation of hydrogen bonding and of a charge transfer complex between TCM and amines and to structural effects. The partial molar volumes at infinite dilution of each component (V-bar{sub i}{sup oo}) have been determined using three different methods.

  12. Role of amine oxidase expression to maintain putrescine homeostasis in Rhodococcus opacus.

    Science.gov (United States)

    Foster, Alexander; Barnes, Nicole; Speight, Robert; Morris, Peter C; Keane, Mark A

    2013-04-10

    While applications of amine oxidases are increasing, few have been characterised and our understanding of their biological role and strategies for bacteria exploitation are limited. By altering the nitrogen source (NH4Cl, putrescine and cadaverine (diamines) and butylamine (monoamine)) and concentration, we have identified a constitutive flavin dependent oxidase (EC 1.4.3.10) within Rhodococcus opacus. The activity of this oxidase can be increased by over two orders of magnitude in the presence of aliphatic diamines. In addition, the expression of a copper dependent diamine oxidase (EC 1.4.3.22) was observed at diamine concentrations>1mM or when cells were grown with butylamine, which acts to inhibit the flavin oxidase. A Michaelis-Menten kinetic treatment of the flavin oxidase delivered a Michaelis constant (KM)=190μM and maximum rate (kcat)=21.8s(-1) for the oxidative deamination of putrescine with a lower KM (=60μM) and comparable kcat (=18.2s(-1)) for the copper oxidase. MALDI-TOF and genomic analyses have indicated a metabolic clustering of functionally related genes. From a consideration of amine oxidase specificity and sequence homology, we propose a putrescine degradation pathway within Rhodococcus that utilises oxidases in tandem with subsequent dehydrogenase and transaminase enzymes. The implications of PUT homeostasis through the action of the two oxidases are discussed with respect to stressors, evolution and application in microbe-assisted phytoremediation or bio-augmentation.

  13. Neighboring Hetero-Atom Assistance of Sacrificial Amines to Hydrogen Evolution Using Pt-Loaded TiO2-Photocatalyst

    Directory of Open Access Journals (Sweden)

    Masahide Yasuda

    2014-05-01

    Full Text Available Photocatalytic H2 evolution was examined using Pt-loaded TiO2-photocatalyst in the presence of amines as sacrificial agents. In the case of amines with all of the carbon attached to the hetero-atom such as 2-aminoethanol, 1,2-diamonoethane, 2-amino-1,3-propanediol, and 3-amino-1,2-propanediol, they were completely decomposed into CO2 and water to quantitatively evolve H2. On the other hand, the amines with both hetero-atoms and one methyl group at the β-positions (neighboring carbons of amino group such as 2-amino-1-propanol and 1,2-diaminopropane were partially decomposed. Also, the photocatalytic H2 evolution using amines without the hetero-atoms at the β-positions such as ethylamine, propylamine, 1-butylamine, 1,3-diaminopropane, 2-propylamine, and 2-butylamine was inefficient. Thus, it was found that the neighboring hetero-atom strongly assisted the degradation of sacrificial amines. Moreover, rate constants for H2 evolution were compared among amines. In conclusion, the neighboring hetero-atom did not affect the rate constants but enhanced the yield of hydrogen evolution.

  14. Yeast species utilizing uric acid, adenine, n-alkylamines or diamines as sole source of carbon and energy.

    Science.gov (United States)

    Middelhoven, W J; De Kievit, H; Biesbroek, A L

    1985-01-01

    Yeast strains utilizing uric acid, adenine, monoamines or diamines as sole source of carbon and energy were isolated from several soil samples by the enrichment culture method. The most common species was Trichosporon cutaneum. Strains of Candida catenulata, C. famata, C. parapsilosis, C. rugosa, Cryptococcus laurentii, Stephanoascus ciferrii and Tr. adeninovorans were also isolated. All strains utilizing uric acid as sole carbon source utilized some primary n-alkyl-l-amines, hydroxyamines or diamines as well. The ascomycetous yeast strains showing these characteristics all belonged to species known to assimilate hydrocarbons. Type strains of hydrocarbon-positive yeast species which were not found in the enrichment cultures generally assimilated putrescine, some type strains also butylamine or pentylamine, but none assimilated uric acid. Methanol-positive species were not isolated. Type strains of methanol-positive and of hydrocarbon-negative species did not assimilate uric acid, butylamine or putrescine. Assimilation of putrescine as sole source of carbon and energy may be a valuable diagnostic criterion in yeast taxonomy.

  15. Efficient chemo-enzymatic gluten detoxification: reducing toxic epitopes for celiac patients improving functional properties.

    Science.gov (United States)

    Ribeiro, Miguel; Nunes, Fernando M; Guedes, Sofia; Domingues, Pedro; Silva, Amélia M; Carrillo, Jose Maria; Rodriguez-Quijano, Marta; Branlard, Gérard; Igrejas, Gilberto

    2015-12-22

    Protein engineering of gluten, the exogenous effector in celiac disease, seeking its detoxification by selective chemical modification of toxic epitopes is a very attractive strategy and promising technology when compared to pharmacological treatment or genetic engineering of wheat. Here we present a simple and efficient chemo-enzymatic methodology that decreases celiac disease toxic epitopes of gluten proteins improving its technological value through microbial transglutaminase-mediated transamidation of glutamine with n-butylamine under reducing conditions. First, we found that using low concentrations of amine-nucleophile under non-reducing conditions, the decrease in toxic epitopes is mainly due to transglutaminase-mediated cross-linking. Second, using high amine nucleophile concentrations protein cross-linking is substantially reduced. Third, reducing conditions increase 7-fold the transamidation reaction further decreasing toxic epitopes amount. Fourth, using n-butylamine improves gluten hydrophobicity that strengthens the gluten network. These results open the possibility of tailoring gluten for producing hypoallergenic flours while still taking advantage of the unique viscoelastic properties of gluten.

  16. Secondary organic aerosol formation from primary aliphatic amines with NO3 radical

    Directory of Open Access Journals (Sweden)

    P. J. Silva

    2009-03-01

    Full Text Available Primary aliphatic amines are an important class of nitrogen containing compounds emitted from automobiles, waste treatment facilities and agricultural animal operations. A series of experiments conducted at the UC-Riverside/CE-CERT Environmental Chamber is presented in which oxidation of methylamine, ethylamine, propylamine, and butylamine with O3 and NO3 have been investigated. Very little aerosol formation is observed in the presence of O3 only. However, after addition of NO, and by extension NO3, large aerosol mass yields (~44% for butylamine are seen. Aerosol generated was determined to be organic in nature due to the small fraction of NO and NO2 in the total signal (<1% for all amines tested as detected by an aerosol mass spectrometer (AMS. We propose a reaction mechanism between carbonyl containing species and the parent amine leading to formation of particulate imine products. These findings can have significant impacts on rural communities with elevated nighttime PM loadings, when significant levels of NO3 exist.

  17. Pyrrole Hydrogenation over Rh(111) and Pt(111) Single-Crystal Surfaces and Hydrogenation Promotion Mediated by 1-Methylpyrrole: A Kinetic and Sum-Frequency Generation Vibrational Spectroscopy Study

    Energy Technology Data Exchange (ETDEWEB)

    Kliewer, Christopher J.; Bieri, Marco; Somorjai, Gabor A.

    2008-03-04

    Sum-frequency generation (SFG) surface vibrational spectroscopy and kinetic measurements using gas chromatography have been used to study the adsorption and hydrogenation of pyrrole over both Pt(111) and Rh(111) single-crystal surfaces at Torr pressures (3 Torr pyrrole, 30 Torr H{sub 2}) to form pyrrolidine and the minor product butylamine. Over Pt(111) at 298 K it was found that pyrrole adsorbs in an upright geometry cleaving the N-H bond to bind through the nitrogen evidenced by SFG data. Over Rh(111) at 298 K pyrrole adsorbs in a tilted geometry relative to the surface through the p-aromatic system. A pyrroline surface reaction intermediate, which was not detected in the gas phase, was seen by SFG during the hydrogenation over both surfaces. Significant enhancement of the reaction rate was achieved over both metal surfaces by adsorbing 1-methylpyrrole before reaction. SFG vibrational spectroscopic results indicate that reaction promotion is achieved by weakening the bonding between the N-containing products and the metal surface because of lateral interactions on the surface between 1-methylpyrrole and the reaction species, reducing the desorption energy of the products. It was found that the ring-opening product butylamine was a reaction poison over both surfaces, but this effect can be minimized by treating the catalyst surfaces with 1-methylpyrrole before reaction. The reaction rate was not enhanced with elevated temperatures, and SFG suggests desorption of pyrrole at elevated temperatures.

  18. A fiber-optic sensor to detect volatile organic compounds based on a porous silica xerogel film.

    Science.gov (United States)

    Echeverría, Jesús C; de Vicente, Pablo; Estella, Juncal; Garrido, Julián J

    2012-09-15

    Fiber-optic sensors are increasingly used for the determination of volatile organic compounds (VOCs) in air matrices. This paper provides experimental results on the sensitivity of a fiber-optic sensor that uses a film of a porous silica xerogel as the sensing element. This film was synthesized by the sol-gel process and affixed to the end of the optical fiber by the dip-coating technique. This intrinsic sensor works in reflection mode, and the transduction takes place in the light that travels through the core of the fiber. The VOCs included in this research cover a wide range of compounds with different functional groups and polarities. The highest sensitivity was for 2-propanol (13.1±1.4 M(-1) nm(-1)), followed by toluene (11.4±1.4 M(-1) nm(-1)), and 1-butylamine (9.5±0.4 M(-1) nm(-1)). Acetone and cyclohexane had the lowest sensitivity of all studied VOCs. Limits of detection varied between 9.1×10(-5) M for 1-butylamine and 1.6×10(-3) M for ethanol. Silanol groups on the xerogel surface act as weak acids and interact strongly with molecules that contain OH groups like alcohols, π-electrons like toluene, or a lone pair of electrons like toluene. Stronger interaction of methanol and ethanol with the silanol groups on the film led to some irreversible adsorption of these analytes at room temperature.

  19. Pyrolytic synthesis and characterization of N-doped carbon nanoflakes for electrochemical applications

    Energy Technology Data Exchange (ETDEWEB)

    Savilov, S.V., E-mail: savilov@chem.msu.ru [M.V. Lomonosov Moscow State University, Department of Chemistry, Leninskie gory, 1-3, Moscow 119991 (Russian Federation); N.S. Kurnakov Institute of General and Inorganic Chemistry Of Russian Academy of Sciences, Leninsky avenue, 31, Moscow 119991 (Russian Federation); Arkhipova, E.A. [M.V. Lomonosov Moscow State University, Department of Chemistry, Leninskie gory, 1-3, Moscow 119991 (Russian Federation); N.S. Kurnakov Institute of General and Inorganic Chemistry Of Russian Academy of Sciences, Leninsky avenue, 31, Moscow 119991 (Russian Federation); Ivanov, A.S.; Maslakov, K.I [M.V. Lomonosov Moscow State University, Department of Chemistry, Leninskie gory, 1-3, Moscow 119991 (Russian Federation); Shen, Z. [Nanyang Technological University, Centre for Disruptive Photonic Technologies, 637371 Singapore (Singapore); Aldoshin, S.M.; Lunin, V.V. [M.V. Lomonosov Moscow State University, Department of Chemistry, Leninskie gory, 1-3, Moscow 119991 (Russian Federation)

    2015-09-15

    Highlights: • Carbon nanoflakes doped with nitrogen were produced by a pyrolytic technique. • Quarternary, pyrrolic and pyridinic types of nitrogen are confirmed by XPS. • Nitrogen content depends on precursor used and temperature processed. • Specific surface area values decrease with increasing of synthesis duration. • N-doped carbon nanoflakes may be suitable for electrochemical applications. - Abstract: Nitrogen doped carbon nanoflakes, which are very important for many electrochemical applications, were synthesized by pyrolysis of nitrogen containing organic compounds over metal oxide template. Acetonitrile, pyridine and butylamine, which are of different volatility were tested as N-containing precursors. Morphology, structure and chemical composition of the as-synthesized materials were investigated by scanning electron microscopy (SEM), high resolution transmission electron microscopy (TEM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). It was found that materials are highly defective and consist of a few malformed graphene layers. X-ray photoelectron spectra reflect the dominant graphitic and pyridinic N-bonding configuration. It was also noted that specific surface area depends on the duration and temperature of the reaction. Increase in duration and temperature led to decrease of the specific surface area from 1000 to 160 m{sup 2}/g, 1170 to 210 m{sup 2}/g and 1180 to 480 m{sup 2}/g for acetonitrile, butylamine and pyridine precursors, respectively.

  20. Effects of synthetic conditions on the structure and morphology of open-ended vanadium oxide nanotubes and study of their growth mechanism

    Institute of Scientific and Technical Information of China (English)

    WEI Jia; ZHU Ying; ZHANG JingChang

    2007-01-01

    Vanadium oxide nanotubes (Vox-NTs) have been synthesized by using n-butylamine as structure- directing template and V2O5 as precursor under hydrothermal conditions. XRD, FTIR, SEM, TEM, BET and TG-DTA characterizations have been performed to both optimize the synthetic conditions and understand the growth mechanism of Vox-NTs. The results showed that open-ended Vox-NTs were obtained under the optimized conditions (hydrothermal temperature: 150-160°C, hydrothermal time: 5-7 d, the molar ratio of V2O5 to n-butylamine is 1:1) with diameters ranging from about 30 to 100 nm and several micrometers in length. The BET surface area and the desorption cumulative pore volume of pores of the as-synthesized sample were about 27.4609 m2/g and 0.191087 cm3/g, respectively. The result presents that the synthesis of Vox-NTs is controlled by the "rolling" mechanism and temperature is primary driving force for rolling.

  1. 2,3,6 Trioxypentafulrene, 5(1): reactivity to primary-amines, nucleophilic substitution and ring expansion; 2,3,6 trioxipentafulvenos, 5(1): reactividad frente a aminas primarias: sustitucion nucleofilica y expansion de anillo

    Energy Technology Data Exchange (ETDEWEB)

    Victory, P.; Alvarez-Larena, A.; Pinilla, J.F.; Germain, G.; Solar, E.; Munoz, M. [Departamento de Quimica Organica, Instituto Quimico de Sarria, Barcelona (Spain)

    1995-11-01

    The reaction between dimethyl 2,3,6-trihydroxypenta-fulvene-1,4-dicarboxylate and primary alkyl or cycloalkylamines (methylamine, butylamine, cyclooactylamine, cyclohexylamine) affords the corresponding 6-aminopentafulvenes (nucleophilic substitution of the C6 hydroxyl group by the amine) or dimethyl 5-amino-2,3-dihydroxyterephthalates (ring expansion) depending on the reaction conditions. For the two kinds of compounds both a spectroscopic study and a single crystal X-ray analysis have been carried out. Different hydrogen bondings have been observed. Only the substitution products are obtained in the reaction between dimethyl 2,3,6-trihydroxypentafulvene-1,4-dicarboxylate and primary aromatic amines (aniline, 4-sec-butylaniline, p-anisidine). When p-nitroaniline or p-aminobenzonitrile are used the reaction does not progress. 26 refs.

  2. Isopropylation of benzene with 2-propanol over substituted large pore aluminophosphate-based molecular sieves

    Indian Academy of Sciences (India)

    K Joseph Antony Raj; V R Vijayaraghavan

    2004-03-01

    Large pore aluminophosphate-based molecular sieves like AlPO4-5, MAPO-5, MnAPO-5 and ZAPO-5 were synthesised hydrothermally using triethylamine as a structure directing agent. These materials were characterised by X-ray diffraction (XRD), 27Al and 31P MAS-NMR, ICP-MS, -butylamine- TPD, BET and SEM. The catalytic performance of these materials was tested for isopropylation of benzene with 2-propanol at 250, 300, 350 and 400°C. The products were cumene, -DIPB (-diisopropylbenzene) and -DIPB (-diisopropylbenzene). MnAPO-5 was found to be more active than the other catalysts. Maximum conversion (20%) was noted at 350°C over MnAPO-5. The selectivity to DIPB was found to decrease with time on stream but the selectivity to cumene showed an increase after 3 h of time on stream.

  3. Porous Silicates Modified with Zirconium Oxide and Sulfate Ions for Alcohol Dehydration Reactions

    Directory of Open Access Journals (Sweden)

    Heriberto Esteban Benito

    2015-01-01

    Full Text Available Porous silicates were synthesized by a nonhydrothermal method, using sodium silicate as a source of silica and cetyltrimethylammonium bromide as a template agent. Catalysts were characterized using thermogravimetric analysis, N2 physisorption, X-ray diffraction, FTIR spectroscopy, pyridine adsorption, potentiometric titration with n-butylamine, scanning electronic microscopy, and transmission electronic microscopy. The surface area of the materials synthesized was greater than 800 m2/g. The introduction of zirconium atoms within the porous silicates increased their acid strength from −42 to 115 mV, while the addition of sulfate ions raised this value to 470 mV. The catalytic activity for the dehydration of alcohols yields conversions of up to 70% for ethanol and 30% for methanol.

  4. Solution-phase synthesis of nanomaterials at low temperature

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    This paper reviews the solution-phase synthesis of nanoparticles via some routes at low temperatures, such as room temperature route, wave-assisted synthesis (γ-irradiation route and sonochemical route), directly heating at low temperatures, and hydrothermal/solvothermal methods. A number of strategies were developed to control the shape, the size, as well as the dispersion of nanostructures. Using diethylamine or n-butylamine as solvent, semiconductor nanorods were yielded. By the hydrothermal treatment of amorphous colloids, Bi2S3 nanorods and Se nanowires were obtained. CdS nanowires were prepared in the presence of polyacrylamide. ZnS nanowires were obtained using liquid crystal. The polymer poly (vinyl acetate) tubule acted as both nanoreactor and template for the CdSe nanowire growth. Assisted by the surfactant of sodium dodecyl benzenesulfonate (SDBS), nickel nanobelts were synthesized. In addition, Ag nanowires, Te nanotubes and ZnO nanorod arrays could be prepared without adding any additives or templates.

  5. Coulometric titrations of bases in propylene carbonate and g-butyrolactone using hydroquinone as the depolarizer and a quinhydrone indicator electrode

    Directory of Open Access Journals (Sweden)

    Z. D. STANIC

    2000-08-01

    Full Text Available The application of hydroquinone for the coulometric generation of hydrogen ions in propylene carbonate (PC and g-butyrolactone (GBL is described. The current-potential curves recorded for theid sepolarizer, titrated bases, indicator and the solvents used showed that the investigated depolarizer is oxidized at lower potentials than the oxidation potentials of other components in the solution. the hydrogen ions generated by the oxidation of hydroquinone were used for the titration of organic bases (triethylamine, n-butylamine, pyridine, quinoline, aniline, N,N’-diphenylguanidine, piperidine, and 2,2’-bipiridine in PC and GBL with visual (Crystal Violet as indicator and potentiometric end-point detection using a quinhydrone electrode as the indicator electrode. The quinhydrone added to the to be analyzed solution served both as a source of hydrogen ions and, together with the immersed platinum electrode, as a quinhydrone electrode. The relative error of the determination of the bases was about 1 %.

  6. Self-Assembled PbSe Nanowire:Perovskite Hybrids.

    Science.gov (United States)

    Yang, Zhenyu; Yassitepe, Emre; Voznyy, Oleksandr; Janmohamed, Alyf; Lan, Xinzheng; Levina, Larissa; Comin, Riccardo; Sargent, Edward H

    2015-12-02

    Inorganic semiconductor nanowires are of interest in nano- and microscale photonic and electronic applications. Here we report the formation of PbSe nanowires based on directional quantum dot alignment and fusion regulated by hybrid organic-inorganic perovskite surface ligands. All material synthesis is carried out at mild temperatures. Passivation of PbSe quantum dots was achieved via a new perovskite ligand exchange. Subsequent in situ ammonium/amine substitution by butylamine enables quantum dots to be capped by butylammonium lead iodide, and this further drives the formation of a PbSe nanowire superlattice in a two-dimensional (2D) perovskite matrix. The average spacing between two adjacent nanowires agrees well with the thickness of single atomic layer of 2D perovskite, consistent with the formation of a new self-assembled semiconductor nanowire:perovskite heterocrystal hybrid.

  7. Carbon assimilation and extracellular antigens of some yeast-like fungi.

    Science.gov (United States)

    Middelhoven, W J; De Hoog, G S; Notermans, S

    1989-01-01

    Many yeast-like fungi assimilated n-hexadecane, butylamine and putrescine as sole carbon sources. Methanol was not assimilated. This points to a physiological similarity to endomycetous, hydrocarbon-utilizing yeasts. Stephanoascus ciferrii assimilated uric acid, adenine and allantoin as sole source of carbon and nitrogen. All strains of Geotrichum candidum and many other yeast-like fungi assimilated acetoin and butan-2,3-diol. Assimilation tests for adenine, uric acid, allantoin, acetoin and butan-2,3-diol were found to be suitable for taxonomic purposes. Extracellular antigens immunologically related to those produced by Geotrichum candidum were detected in the cell-free culture liquids of several yeast-like fungi. The extracellular antigen excreted by Stephanoascus ciferrii was species-specific.

  8. No cytotoxic nitrogen-doped carbon nanotubes as efficient metal-free electrocatalyst for oxygen reduction in fuel cells

    Science.gov (United States)

    Jin, Haiying; Zhu, Luping; Bing, Naicing; Wang, Lingling; Wang, Lijun

    2014-04-01

    Bamboo-like nitrogen-doped carbon nanotubes (NCNTs) with different nitrogen content have been synthesized by chemical vapor deposition (CVD) under different reaction temperature of 600-900 °C. The butylamine and FeY have been used as precursor and catalyst, respectively. The electrocatalytic property of the NCNTs catalyst in oxygen reduction was examined by cyclic voltammetry. The results revealed that the NCNTs catalyst has higher catalytic activity than the commonly used Pt/C catalyst (Pt-CNTs, 20% of Pt/C, BASF), suggesting potential applications in fuel cells. On the other hand, the cytotoxic effects of NCNTs materials showed no cytotoxic to SPCA-1 cells, of which Pt-CNTs and CNTs particles indicated notably high cytotoxic. From these results, more application fields might be found for NCNTs except for as cathodic catalyst in fuel cells (FCs).

  9. Synthesis and characterization of nano/micro structured crystalline germanium dioxide with novel morphology

    Institute of Scientific and Technical Information of China (English)

    WANG XiaoYan; DUAN Lian; DONG GuiFang; WEI Peng; WANG Wei; WANG LiDuo; QIU Yong

    2009-01-01

    Nano/micro-structured germanium oxide (GeO2) was prepared using GeCl4 and KOH by a simple solution method in alkalic alcoholic solution.Different morphologies of GeO2 were obtained by changing the reaction conditions.The effects of the reaction time,the concentration of the reactants,the reaction temperature and the dispersant upon the morphology of the deposited GeO2 have been investigated.The products were detected by X-ray diffraction (XRD),atomic force microscope (AFM),scanning electron microscope (SEM) and transmission electron microscope (TEM).Novel cross-like structures were obtained by using n-butylamine as the dispersant.The formation of the cross-like structures has been discussed and a solution-liquid-solid (SLS) mechanism was proposed.

  10. Dehydration of lactic acid to acrylic acid over lanthanum phosphate catalysts: the role of Lewis acid sites.

    Science.gov (United States)

    Guo, Zhen; Theng, De Sheng; Tang, Karen Yuanting; Zhang, Lili; Huang, Lin; Borgna, Armando; Wang, Chuan

    2016-09-14

    Lanthanum phosphate (LaP) nano-rods were synthesized using n-butylamine as a shape-directing agent (SDA). The resulting catalysts were applied in the dehydration of lactic acid to acrylic acid. Aiming to understand the nature of the active sites, the chemical and physical properties of LaP materials were studied using a variety of characterization techniques. This study showed that the SDA not only affected the porosity of the LaP materials but also modified the acid-base properties. Clearly, the modification of the acid-base properties played a more critical role in determining the catalytic performance than porosity. An optimized catalytic performance was obtained on the LaP catalyst with a higher concentration of Lewis acid sites. Basic sites showed negative effects on the stability of the catalysts. Good stability was achieved when the catalyst was prepared using the appropriate SDA/La ratio.

  11. Autoinduced catalysis and inverse equilibrium isotope effect in the frustrated Lewis pair catalyzed hydrogenation of imines.

    Science.gov (United States)

    Tussing, Sebastian; Greb, Lutz; Tamke, Sergej; Schirmer, Birgitta; Muhle-Goll, Claudia; Luy, Burkhard; Paradies, Jan

    2015-05-26

    The frustrated Lewis pair (FLP)-catalyzed hydrogenation and deuteration of N-benzylidene-tert-butylamine (2) was kinetically investigated by using the three boranes B(C6F5)3 (1), B(2,4,6-F3-C6H2)3 (4), and B(2,6-F2-C6H3)3 (5) and the free activation energies for the H2 activation by FLP were determined. Reactions catalyzed by the weaker Lewis acids 4 and 5 displayed autoinductive catalysis arising from a higher free activation energy (2 kcal mol(-1)) for the H2 activation by the imine compared to the amine. Surprisingly, the imine reduction using D2 proceeded with higher rates. This phenomenon is unprecedented for FLP and resulted from a primary inverse equilibrium isotope effect.

  12. Equilibria and kinetics for pH-dependent axial ligation of bromomethyl(aquo)cobaloxime by aliphatic amine ligands

    Indian Academy of Sciences (India)

    M Bhoopal; N Ravi Kumar Reddy; S Satyanarayana

    2003-04-01

    Kinetics and equilibria of axial ligation of bromomethyl(aquo) cobaloxime by a series of straight chain primary amines (methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine), cycloamines (cyclopentylamine, cyclohexylamine, cycloheptylamine) and secondary amines (N,N-dimethylamine, N,N-diethylamine) have been measured as functions of pH by spectrophotometric technique in aqueous solution, ionic strength 1 M (KCl) at 25°C. The rate of substitution of H2O varies with the Ka of incoming ligand, thus establishing nucleophilic participation of the ligand in the transition state. Binding and kinetic data are interpreted based on the basicity and steric influence of the entering ligand. To compare the rate constants of the entering ligands, pH independent second-order rate constants (on) are calculated.

  13. Research into aroma changes in irradiated foodstuffs. I.- Studies on Fish; Investigacion de Alteraciones de Aroma en alimentos irradiados. I Estudio sobre Pescado

    Energy Technology Data Exchange (ETDEWEB)

    Barreiro Pinero, R.; Gasco Sanchez, L.; Valverde Garcia, F.

    1972-07-01

    Radiolytic formation of volatile compounds have been investigated in fillets of hake, codfish and bonito gamma-irradiated at a dose range of 0.1-5 Mrads. Analytical methods have been developed by gas chromatography of functional group derivatives: carbonyls as 2,4,-dinitrophenyl hydrazones, primary and secondary amines as N-alkyl benzamides, and thiols as 2,4-dinitrophenyl alkyl thioethers. The main results are as follows: increasing with the integral dose of the whole carbonyls, the most significant components being acetaldehyde, propional dehyde and formaldehyde; no significant variations with the integral dose od the traces of ammonia, methylamine, trimethylamine, ethylamine, diethylamine, propylamine, butylamine and pentylamine found in unirradiated samples; and radiolytic formation of methanethiol and dimethyl disulfide. (Author) 98 refs.

  14. Self-Assembled PbSe Nanowire:Perovskite Hybrids

    KAUST Repository

    Yang, Zhenyu

    2015-12-02

    © 2015 American Chemical Society. Inorganic semiconductor nanowires are of interest in nano- and microscale photonic and electronic applications. Here we report the formation of PbSe nanowires based on directional quantum dot alignment and fusion regulated by hybrid organic-inorganic perovskite surface ligands. All material synthesis is carried out at mild temperatures. Passivation of PbSe quantum dots was achieved via a new perovskite ligand exchange. Subsequent in situ ammonium/amine substitution by butylamine enables quantum dots to be capped by butylammonium lead iodide, and this further drives the formation of a PbSe nanowire superlattice in a two-dimensional (2D) perovskite matrix. The average spacing between two adjacent nanowires agrees well with the thickness of single atomic layer of 2D perovskite, consistent with the formation of a new self-assembled semiconductor nanowire:perovskite heterocrystal hybrid.

  15. Purification and characterization of methylamine oxidase induced in Aspergillus niger AKU 3302.

    Science.gov (United States)

    Frébort, I; Matsushita, K; Toyama, H; Lemr, K; Yamada, M; Adachi, O

    1999-01-01

    Crude extract of Aspergillus niger AKU 3302 mycelia incubated with methylamine showed a single amine oxidase activity band in a developed polyacrylamide gel that weakly cross-reacted with the antibody against a copper/topa quinone-containing amine oxidase (AO-II) from the same strain induced by n-butylamine. Since the organism cannot grow on methylamine and the already known quinoprotein amine oxidases of the organism cannot catalyze oxidation of methylamine, the organism was forced to produce another enzyme that could oxidize methylamine when the mycelia were incubated with methylamine. The enzyme was separated and purified from the already known two quinoprotein amine oxidases formed in the same mycelia. The purified enzyme showed a sharp symmetric sedimentation peak in analytical ultracentrifugation showing S20,w0 of 6.5s. The molecular mass of 133 kDa estimated by gel chromatography and 66.6 kDa found by SDS-PAGE confirmed the dimeric structure of the enzyme. The purified enzyme was pink in color with an absorption maximum at 494 nm. The enzyme readily oxidized methylamine, n-hexylamine, and n-butylamine, but not benzylamine, histamine, or tyramine, favorite substrates for the already known two quinoprotein amine oxidases. Inactivation by carbonyl reagents and copper chelators suggested the presence of a copper/topa quinone cofactor. Spectrophotometric titration by p-nitrophenylhydrazine showed one reactive carbonyl group per subunit and redox-cyclic quinone staining confirmed the presence of a quinone cofactor. pH-dependent shift of the absorption spectrum of the enzyme-p-nitrophenylhydrazone (469 nm at neutral to 577 nm at alkaline pH) supported the identity of the cofactor with topaquinone. Nothern blot analysis indicated that the methylamine oxidase encoding gene is largely different from the already known amine oxidase in the organism.

  16. Preparation of Magnesium Hydroxide Flame Retardant with Additives%添加剂辅助制备氢氧化镁阻燃剂

    Institute of Scientific and Technical Information of China (English)

    张红进

    2012-01-01

    Magnesium hydroxide is a kind of flame retardant with high anti -flame effect, which is widely used in high polymer, such as plastic, rubber. In the experiment, synthesis reaction - hydrothermal treatment the flame - retardant magnesium hydroxide is prepared by the two -stpe way( ammonia synthesis reaction - hydrothermal treatment) with the help of additives and the products are detected by XRD, SEM and TEM methods. The results show that; ethylenediamine, n - butylamine and sodium stearate have enhancing effect on the preparation of Magnesium hydroxide , flame retardant, especially for the combination of n - butylamine and sodium stearate, and ethanol has no effect in this aspect.%氢氧化镁因具有良好的阻燃效果而被广泛应用于塑料、橡胶等高聚物中.实验使用两步法(氨水合成—水热处理法)在几种添加剂辅助条件下制备氢氧化镁阻燃剂粉体,对制备出的粉体进行了XRD、SEM和TEM表征.结果表明,加入有机添加剂对水热制备氢氧化镁阻燃剂影响较大,乙二胺、正丁胺、硬脂酸钠对制备阻燃型氢氧化镁具有促进作用,正丁胺和硬脂酸钠复合使用效果更佳,而无水乙醇未表现出促进作用.

  17. cine-Substitution reactions of metallabenzenes: an experimental and computational study.

    Science.gov (United States)

    Wang, Tongdao; Zhang, Hong; Han, Feifei; Long, Lipeng; Lin, Zhenyang; Xia, Haiping

    2013-08-12

    Alkali-resistant osmabenzene [(SCN)2(PPh3)2Os{CHC(PPh3)CHCICH}] (2) can undergo nucleophilic aromatic substitution with MeOH or EtOH to give cine-substitution products [(SCN)2(PPh3)2Os{CHC(PPh3)CHCHCR}] (R=OMe (3), OEt(4)) in the presence of strong alkali. However, the reactions of compound 2 with various amines, such as n-butylamine and aniline, afford five-membered ring species, [(SCN)2(PPh3)2Os{CH=C(PPh3)CH=C(CH=NHR')}] (R'=nBu(8), Ph(9)), in addition to the desired cine-substitution products, [(SCN)2(PPh3)2Os{CHC(PPh3)CHCHC(NHR')}] (R'=nBu(6), Ph(7)), under similar reaction conditions. The mechanisms of these reactions have been investigated in detail with the aid of isotopic labeling experiments and density functional theory (DFT) calculations. The results reveal that the cine-substitution reactions occur through nucleophilic addition, dissociation of the leaving group, protonation, and deprotonation steps, which resemble the classical "addition-of-nucleophile, ring-opening, ring-closure" (ANRORC) mechanism. DFT calculations suggest that, in the reaction with MeOH, the formation of a five-membered metallacycle species is both kinetically and thermodynamically less favorable, which is consistent with the experimental results that only the cine-substitution product is observed. For the analogous reaction with n-butylamine, the pathway for the formation of the cine-substitution product is kinetically less favorable than the pathway for the formation of a five-membered ring species, but is much more thermodynamically favorable, again consistent with the experimental conversion of compound 8 into compound 6, which is observed in an in situ NMR experiment with an isolated pure sample of 8.

  18. Effect of Modified Bentonite and Laponite Compound on AKD Emulsification and Sizing Performance of the AKD Emulsion on BCTMP%改性膨润土与改性锂皂石复配对AKD的乳化及乳液对BCTMP的施胶性能

    Institute of Scientific and Technical Information of China (English)

    刘宗印; 刘温霞

    2012-01-01

    The modification of laponite by n-butylamine as well as the emulsification and stabilization of the modified laponite together with NaF modified bentonite on AKD were investigated,meanwhile the sizing performance of the AKD emulsion on BCTMP was also studied in this paper.The results showed that when the dosages of modified bentonite,n-butylamine,laponite were 4wt%(based on AKD),6wt%(based on laponite),and 2.5wt%(based on AKD),respectively,AKD Pickering emulsion(O/W type) with better emulsion stability and sizing performance was obtained.%探讨了正丁胺对锂皂石的改性及与氟化钠改性膨润土进行复配对烷基烯酮二聚体(AKD)的乳化与稳定作用,同时研究了所制备的AKD乳液的浆内施胶性能。结果表明,当改性膨润土用量为4%(相对于AKD质量,下同)、正丁胺用量为6%(相对于锂皂石质量,下同)、锂皂石用量为2.5%(相对于AKD质量,下同)时,可将AKD乳化成水包油型Pickering乳液,并且所制备的乳液稳定性和施胶性能较好。

  19. Formation of simple biomolecules from alanine in ocean by impacts

    Science.gov (United States)

    Umeda, Y.; Sekine, T.; Furukawa, Y.; Kakegawa, T.; Kobayashi, T.

    2013-12-01

    phenylalanine) and four amines (methylamine, ethylamine, propylamine, and butylamine). The results in the presence of olivine have indicated the formation glycine, methylamine, ethylamine, propylamine, and butylamine. However, the results in the presence of Fe2O3 detect little glycine, methylamine, and ethylamine but no formation of propylamine and butylamine. Valine, and phenylalanine were not detected. The survival alanine as a function of pressure has been affected significantly by the oxygen fugacity, and there seems to be a threshold pressure of around 5.2 GPa. On the other hand, the glycine in alanine solution was below 5% being little variation. We have checked the solid run products by XRD. Peaks for olivine did not change, but past of Fe2O3 changed to Fe3O4. Thermodynamic calculation gives oxygen fugacities for these assemblies. These experimental results on alanine suggest that simple amino acid may be affected by pressure, oxygen fugacity, and chemical environments during impact.

  20. 1D coordination polymers with polychalcogenides as linkers between metal atoms

    Energy Technology Data Exchange (ETDEWEB)

    Kysliak, Oleksandr; Beck, Johannes, E-mail: j.beck@uni-bonn.de

    2013-07-15

    The reactions of zinc metal with elemental selenium and selenium/sulfur mixtures in liquid ammonia or methylamine under solvothermal conditions in closed glass ampoules at 50 °C lead within some days specifically to [Zn(NH{sub 3}){sub 2}Se{sub 4}]{sub n} (1), [Zn(MeNH{sub 2}){sub 2}Se{sub 4}]{sub n} (2), [Zn(NH{sub 3}){sub 2}Se{sub 2.23}S{sub 1.77}]{sub n} (3). From MnCl{sub 2}, Rb{sub 2}Se and excess Se in n-butylamine [Mn({sup n}BuNH{sub 2}){sub 4}Se{sub 6}]{sub n} (4) is obtained after prolonged reaction time at ambient temperature. The compounds are sensitive towards air and loss of NH{sub 3} or the amine ligands. The crystal structures were determined by single crystal diffraction at low temperatures. As a common structural feature, all compounds represent 1D coordination polymers with polychalcogenide chains as linkers between the metal atoms and consist of infinite [M–Ch{sub m}–]{sub n} chains (M=Zn, Mn; Ch{sub m}=Se{sub 4}, (S/Se){sub 4}, Se{sub 6}). The Zn central atoms in 1–3 have tetrahedral coordination with two amine ligands, the Mn atoms in 4 have octahedral coordination with four amine ligands and cis position of the two Se atoms. Raman spectra of 1–3 show the stretching mode vibrations of the Ch{sub 4} groups. The observation of S–S, S–Se, and Se–Se vibration bands in the spectrum of 3 indicates the presence of mixed S/Se polyanions. An optical band gap of 1.86(5) eV was determined for 2 by diffuse reflectance spectroscopy. - Graphical abstract: The reaction of Zn and Se in liquid methylamine yields dark red [Zn(NH{sub 2}CH{sub 3})Se{sub 4}], a 1D coordination polymer consisting of helical Zn–Se{sub 4}–Zn– chains. - Highlights: • A series of 1D coordination polymers consisting of metal amine complexes concatenated by polychalcogenide ions is presented. • Syntheses were performed as solvothermal reactions in liquid ammonia, liquid methylamine and n-butylamine. • Crystal structures are dominated by helices [M–Ch{sub m

  1. CCN activity of aliphatic amine secondary aerosol

    Science.gov (United States)

    Tang, X.; Price, D.; Praske, E.; Vu, D.; Purvis-Roberts, K.; Silva, P. J.; Cocker, D. R., III; Asa-Awuku, A.

    2014-01-01

    Aliphatic amines can form secondary aerosol via oxidation with atmospheric radicals (e.g. hydroxyl radical and nitrate radical). The particle composition can contain both secondary organic aerosol (SOA) and inorganic salts. The fraction of organic to inorganic materials in the particulate phase influences aerosol hygroscopicity and cloud condensation nuclei (CCN) activity. SOA formed from trimethylamine (TMA) and butylamine (BA) reactions with hydroxyl radical (OH) is composed of organic material of low hygroscopicity (single hygroscopicity parameter, κ ≤ 0.25). Secondary aerosol formed from the tertiary aliphatic amine (TMA) with N2O5 (source of nitrate radical, NO3), contains less volatile compounds than the primary aliphatic amine (BA) aerosol. TMA + N2O5 form semi-volatile organics in low RH conditions that have κ ~ 0.20, indicative of slightly soluble organic material. As RH increases, several inorganic amine salts are formed as a result of acid-base reactions. The CCN activity of the humid TMA-N2O5 aerosol obeys Zdanovskii, Stokes, and Robinson (ZSR) ideal mixing rules. Higher CCN activity (κ > 0.3) was also observed for humid BA+N2O5 aerosols compared with dry aerosol (κ ~ 0.2), as a result of the formation of inorganic salts such as NH4NO3 and butylamine nitrate (C4H11N · HNO3). Compared with TMA, BA+N2O5 reactions produce more volatile aerosols. The BA+N2O5 aerosol products under humid experiments were found to be very sensitive to the temperature within the stream-wise continuous flow thermal gradient CCN counter. The CCN counter, when set above a 21 °C temperature difference, evaporates BA+N2O5 aerosol formed at RH ≥ 30%; κ ranges from 0.4 to 0.7 and is dependent on the instrument supersaturation (ss) settings. The aerosol behaves non-ideally, hence simple ZSR rules cannot be applied to the CCN results from the primary aliphatic amine system. Overall, aliphatic amine aerosol systems κ ranges from 0.2 systems.

  2. CCN activity of aliphatic amine secondary aerosol

    Directory of Open Access Journals (Sweden)

    X. Tang

    2014-01-01

    Full Text Available Aliphatic amines can form secondary aerosol via oxidation with atmospheric radicals (e.g. hydroxyl radical and nitrate radical. The particle composition can contain both secondary organic aerosol (SOA and inorganic salts. The fraction of organic to inorganic materials in the particulate phase influences aerosol hygroscopicity and cloud condensation nuclei (CCN activity. SOA formed from trimethylamine (TMA and butylamine (BA reactions with hydroxyl radical (OH is composed of organic material of low hygroscopicity (single hygroscopicity parameter, κ ≤ 0.25. Secondary aerosol formed from the tertiary aliphatic amine (TMA with N2O5 (source of nitrate radical, NO3, contains less volatile compounds than the primary aliphatic amine (BA aerosol. TMA + N2O5 form semi-volatile organics in low RH conditions that have κ ~ 0.20, indicative of slightly soluble organic material. As RH increases, several inorganic amine salts are formed as a result of acid-base reactions. The CCN activity of the humid TMA-N2O5 aerosol obeys Zdanovskii, Stokes, and Robinson (ZSR ideal mixing rules. Higher CCN activity (κ > 0.3 was also observed for humid BA+N2O5 aerosols compared with dry aerosol (κ ~ 0.2, as a result of the formation of inorganic salts such as NH4NO3 and butylamine nitrate (C4H11N · HNO3. Compared with TMA, BA+N2O5 reactions produce more volatile aerosols. The BA+N2O5 aerosol products under humid experiments were found to be very sensitive to the temperature within the stream-wise continuous flow thermal gradient CCN counter. The CCN counter, when set above a 21 °C temperature difference, evaporates BA+N2O5 aerosol formed at RH ≥ 30%; κ ranges from 0.4 to 0.7 and is dependent on the instrument supersaturation (ss settings. The aerosol behaves non-ideally, hence simple ZSR rules cannot be applied to the CCN results from the primary aliphatic amine system. Overall, aliphatic amine aerosol systems κ ranges from 0.2 < κ < 0.7. This work indicates that

  3. 胺型离子液体催化合成乙酸己酯%Synthesis of hexyl acetate catalyzed by ammonium ionic liquid

    Institute of Scientific and Technical Information of China (English)

    叶庆华; 侯梦吟; 张文霞; 占晓友; 许映杰

    2011-01-01

    合成了硝酸正丁胺(N_4NO_3)、醋酸正丁胺(N_4AC)、醋酸正丙胺(N_3AC)和醋酸乙胺(N_2AC)4种胺型离子液体,采用~1HNMR对其结构进行了表征。以上述胺型离子液体为催化剂,冰醋酸和正己醇为原料,环己烷为带水剂,通过酯化反应制备了乙酸己酯。考察了催化剂种类、反应温度和反应时间等因素对乙酸己酯酯化率的影响,优化了反应工艺。最佳反应条件为:15mL环己烷为带水剂,n(冰醋酸):n(正己醇):n(N_4NO_3)=1:1.2:0.1,反应温度为95℃,反应时间为4.5h,乙酸己酯的酯化率可达90.52%。%Four ammonium ionic liquids,n-butylamine nitrate(N_4NO_3),n-butylamine acetate(N_4AC), n-propylamine acetate(N_3AC) and ethylamine acetate(N_2AC) were synthesized.Their structures were identified by ~1HNMR.The hexyl acetate was synthesized from n-hexanol and acetic acid using the ammonium ionic liquids as the catalyst by direct esterification.The influences of catalyst,reaction temperature and reaction time were investigated. The proper reactions condition was as follow:using 15mL cyclohexane as water carrier agent,n(acetic acid):n(n-hexanol):n(N_4NO_3)=1:1.2:0.1,the reaction temperature was 95℃and reaction time was 4.5h.The yield of the product was 90.5%.

  4. Aliphatic amines in Antarctic CR2, CM2, and CM1/2 carbonaceous chondrites

    Science.gov (United States)

    Aponte, José C.; McLain, Hannah L.; Dworkin, Jason P.; Elsila, Jamie E.

    2016-09-01

    Meteoritic water-soluble organic compounds provide a unique record of the processes that occurred during the formation of the solar system and the chemistry preceding the origins of life on Earth. We have investigated the molecular distribution, compound-specific δ13C isotopic ratios and enantiomeric compositions of aliphatic monoamines present in the hot acid-water extracts of the carbonaceous chondrites LAP 02342 (CR2), GRA 95229 (CR2), LON 94101 (CM2), LEW 90500 (CM2), and ALH 83100 (CM1/2). Analyses of the concentration of monoamines in these meteorites revealed: (a) the CR2 chondrites studied here contain higher concentrations of monoamines relative to the analyzed CM2 chondrites; (b) the concentration of monoamines decreases with increasing carbon number; and (c) isopropylamine is the most abundant monoamine in these CR2 chondrites, while methylamine is the most abundant amine species in these CM2 and CM1/2 chondrites. The δ13C values of monoamines in CR2 chondrite do not correlate with the number of carbon atoms; however, in CM2 and CM1/2 chondrites, the 13C enrichment decreases with increasing monoamine carbon number. The δ13C values of methylamine in CR2 chondrites ranged from -1 to +10‰, while in CM2 and CM1/2 chondrites the δ13C values of methylamine ranged from +41 to +59‰. We also observed racemic compositions of sec-butylamine, 3-methyl-2-butylamine, and sec-pentylamine in the studied carbonaceous chondrites. Additionally, we compared the abundance and δ13C isotopic composition of monoamines to those of their structurally related amino acids. We found that monoamines are less abundant than amino acids in CR2 chondrites, with the opposite being true in CM2 and CM1/2 chondrites. We used these collective data to evaluate different primordial synthetic pathways for monoamines in carbonaceous chondrites and to understand the potential common origins these molecules may share with meteoritic amino acids.

  5. Photoisomerization action spectrum of retinal protonated Schiff base in the gas phase

    Energy Technology Data Exchange (ETDEWEB)

    Coughlan, N. J. A.; Catani, K. J.; Adamson, B. D.; Wille, U.; Bieske, E. J., E-mail: evanjb@unimelb.edu.au [School of Chemistry, The University of Melbourne, Victoria 3010 (Australia)

    2014-04-28

    The photophysical behaviour of the isolated retinal protonated n-butylamine Schiff base (RPSB) is investigated in the gas phase using a combination of ion mobility spectrometry and laser spectroscopy. The RPSB cations are introduced by electrospray ionisation into an ion mobility mass spectrometer where they are exposed to tunable laser radiation in the region of the S{sub 1} ← S{sub 0} transition (420–680 nm range). Four peaks are observed in the arrival time distribution of the RPSB ions. On the basis of predicted collision cross sections with nitrogen gas, the dominant peak is assigned to the all-trans isomer, whereas the subsidiary peaks are assigned to various single, double and triple cis geometric isomers. RPSB ions that absorb laser radiation undergo photoisomerization, leading to a detectable change in their drift speed. By monitoring the photoisomer signal as a function of laser wavelength an action spectrum, extending from 480 to 660 nm with a clear peak at 615 ± 5 nm, is obtained. The photoisomerization action spectrum is related to the absorption spectrum of isolated retinal RPSB molecules and should help benchmark future electronic structure calculations.

  6. MALDI Matrix Research for Biopolymers

    Science.gov (United States)

    Fukuyama, Yuko

    2015-01-01

    Matrices are necessary materials for ionizing analytes in matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS). The choice of a matrix appropriate for each analyte controls the analyses. Thus, in some cases, development or improvement of matrices can become a tool for solving problems. This paper reviews MALDI matrix research that the author has conducted in the recent decade. It describes glycopeptide, carbohydrate, or phosphopeptide analyses using 2,5-dihydroxybenzoic acid (2,5-DHB), 1,1,3,3-tetramethylguanidinium (TMG) salts of p-coumaric acid (CA) (G3CA), 3-aminoquinoline (3-AQ)/α-cyano-4-hydroxycinnamic acid (CHCA) (3-AQ/CHCA) or 3-AQ/CA and gengeral peptide, peptide containing disulfide bonds or hydrophobic peptide analyses using butylamine salt of CHCA (CHCAB), 1,5-diaminonaphthalene (1,5-DAN), octyl 2,5-dihydroxybenzoate (alkylated dihydroxybenzoate, ADHB), or 1-(2,4,6-trihydroxyphenyl)octan-1-one (alkylated trihydroxyacetophenone, ATHAP). PMID:26819908

  7. Ionic liquid matrix-based dispersive liquid-liquid microextraction for enhanced MALDI-MS analysis of phospholipids in soybean.

    Science.gov (United States)

    Shrivas, Kamlesh; Tapadia, Kavita

    2015-09-15

    Ionic liquid matrix (ILM) is found to be a very versatile substance for analysis of broad range of organic molecules in matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) due to good solubility for a variety of analytes, formation of homogenous crystals and high vacuum stability of the matrix. In the present work, an ILM, cyno-4-hydroxycinnamic acid-butylamine (CHCAB) was employed in dispersive liquid-liquid microextraction (DLLME) as sample probe and matrix for extraction and ionization of phospholipids from food samples (soybean) prior to MALDI-MS analysis. With the employed technique, 8-125 fold improvement in signal intensity and limit of detection were achieved for the analysis of phospholipids. The best extraction efficiency of phospholipids in ILM-DLLME was obtained with 5min extraction time in presence 30mg/mL CHCAB and 1.2% NaCl using chloroform as an extracting solvent and methanol as a dispersing solvent. Further, the developed ILM-DLLME procedure has been successfully applied for the analysis of phospholipids in soybean samples in MALDI-MS.

  8. Silanization of Ag-deposited magnetite particles: an efficient route to fabricate magnetic nanoparticle-based Raman barcode materials.

    Science.gov (United States)

    Kim, Kwan; Choi, Jeong-Yong; Lee, Hyang Bong; Shin, Kuan Soo

    2010-07-01

    Silica-coated Ag nanostructures usable as magnetic nanoparticle-based Raman barcode materials were developed. Initially, 283 nm sized spherical magnetite particles composed of 13 nm sized superparamagnetic Fe(3)O(4) nanoparticles were synthesized, and silver deposition was conducted using butylamine as the reductant of AgNO(3) in ethanol. The Ag-deposited Fe(3)O(4) (Fe(3)O(4)@Ag) particles are found to be efficient surface-enhanced Raman scattering (SERS) substrates with the enhancement factor at 632.8 nm excitation to be about 3 x 10(6). After SERS markers such as benzenethiol, 4-mercaptotoluene, 4-aminobenzenethiol, and 4-nitrobenzenethiol were adsorbed onto the silver surface, poly(allylamine hydrochloride) (PAH) was coated onto them using the layer-by-layer deposition method such that a subsequent base-catalyzed silanization could readily form a 60 nm thick silica shell around the PAH layer by a biomimetic process. The cross-linked silica shells effectively prevented the SERS-marker molecules from being liberated from the surface of the Fe(3)O(4)@Ag particles. Although the gram magnetization decreased nearly to one-half of the initial value because of coating with silver and silica, the remaining magnetization was nonetheless strong enough for the silica-coated Fe(3)O(4)@Ag particles to be used as barcode materials operating via SERS.

  9. Sub-10 nm Platinum Nanocrystals with Size and Shape Control: Catalytic Study for Ethylene and Pyrrole Hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Tsung, Chia-Kuang; Kuhn, John N.; Huang, Wenyu; Aliaga, Cesar; Hung, Ling-I; Somorjai, Gabor A.; Yang, Peidong

    2009-03-02

    Platinum nanocubes and nanopolyhedra with tunable size from 5 to 9 nm were synthesized by controlling the reducing rate of metal precursor ions in a one-pot polyol synthesis. A two-stage process is proposed for the simultaneous control of size and shape. In the first stage, the oxidation state of the metal ion precursors determined the nucleation rate and consequently the number of nuclei. The reaction temperature controlled the shape in the second stage by regulation of the growth kinetics. These well-defined nanocrystals were loaded into MCF-17 mesoporous silica for examination of catalytic properties. Pt loadings and dispersions of the supported catalysts were determined by elemental analysis (ICP-MS) and H2 chemisorption isotherms, respectively. Ethylene hydrogenation rates over the Pt nanocrystals were independent of both size and shape and comparable to Pt single crystals. For pyrrole hydrogenation, the nanocubes enhanced ring-opening ability and thus showed a higher selectivity to n-butylamine as compared to nanopolyhedra.

  10. Quantification of Isoxicam in the Presence of Related Compounds by TLC-Densitometry.

    Science.gov (United States)

    Starek, Małgorzata; Krzek, Jan

    2012-06-01

    A simple, sensitive, selective and precise TLC-densitometric determination of isoxicam as a drug was developed and validated. The method employed TLC aluminium plates precoated with silica gel 60 F254 as a stationary phase. The mobile phase consisted of ethyl acetate : toluene : butylamine (2:2:1, v/v/v). The system was found to give good resolution for isoxicam (RF value of 0.56). Densitometric detection was carried out at λ = 350 nm. The calibration plots showed good linear relationship in the working concentration range of 0.7 to 2.2 µg per band. The method was validated for precision (RSD TLC retention times (RF values), absorption spectra and HPLC-MS/MS analysis. The developed TLC-densitometric method can be applied for identification and quantitation of isoxicam in drugs, and it can be using as a screening method in pharmaceutical research. As the TLC method can effectively separate the drug from its degradation products it can be employed as a stability-indicating one and can be utilized to investigate the kinetics of degradation process.

  11. Micropatterned ferrocenyl monolayers covalently bound to hydrogen-terminated silicon surfaces: effects of pattern size on the cyclic voltammetry and capacitance characteristics.

    Science.gov (United States)

    Fabre, Bruno; Pujari, Sidharam P; Scheres, Luc; Zuilhof, Han

    2014-06-24

    The effect of the size of patterns of micropatterned ferrocene (Fc)-functionalized, oxide-free n-type Si(111) surfaces was systematically investigated by electrochemical methods. Microcontact printing with amine-functionalized Fc derivatives was performed on a homogeneous acid fluoride-terminated alkenyl monolayer covalently bound to n-type H-terminated Si surfaces to give Fc patterns of different sizes (5 × 5, 10 × 10, and 20 × 20 μm(2)), followed by backfilling with n-butylamine. These Fc-micropatterned surfaces were characterized by static water contact angle measurements, ellipsometry, X-ray photoelectron spectroscopy (XPS), infrared reflection-absorption spectroscopy (IRRAS), atomic force microscopy (AFM), and scanning electron microscopy (SEM). The charge-transfer process between the Fc-micropatterned and underlying Si interface was subsequently studied by cyclic voltammetry and capacitance. By electrochemical studies, it is evident that the smallest electroactive ferrocenyl patterns (i.e., 5 × 5 μm(2) squares) show ideal surface electrochemistry, which is characterized by narrow, perfectly symmetric, and intense cyclic voltammetry and capacitance peaks. In this respect, strategies are briefly discussed to further improve the development of photoswitchable charge storage microcells using the produced redox-active monolayers.

  12. Cloud condensation nuclei (CCN) activity of aliphatic amine secondary aerosol

    Science.gov (United States)

    Tang, X.; Price, D.; Praske, E.; Vu, D. N.; Purvis-Roberts, K.; Silva, P. J.; Cocker, D. R., III; Asa-Awuku, A.

    2014-06-01

    Aliphatic amines can form secondary aerosol via oxidation with atmospheric radicals (e.g., hydroxyl radical and nitrate radical). The particle can contain both secondary organic aerosol (SOA) and inorganic salts. The ratio of organic to inorganic materials in the particulate phase influences aerosol hygroscopicity and cloud condensation nuclei (CCN) activity. SOA formed from trimethylamine (TMA) and butylamine (BA) reactions with hydroxyl radical (OH) is composed of organic material of low hygroscopicity (single hygroscopicity parameter, κ, ≤ 0.25). Secondary aerosol formed from the tertiary aliphatic amine (TMA) with N2O5 (source of nitrate radical, NO3) contains less volatile compounds than the primary aliphatic amine (BA) aerosol. As relative humidity (RH) increases, inorganic amine salts are formed as a result of acid-base reactions. The CCN activity of the humid TMA-N2O5 aerosol obeys Zdanovskii, Stokes, and Robinson (ZSR) ideal mixing rules. The humid BA + N2O5 aerosol products were found to be very sensitive to the temperature at which the measurements were made within the streamwise continuous-flow thermal gradient CCN counter; κ ranges from 0.4 to 0.7 dependent on the instrument supersaturation (ss) settings. The variance of the measured aerosol κ values indicates that simple ZSR rules cannot be applied to the CCN results from the primary aliphatic amine system. Overall, aliphatic amine aerosol systems' κ ranges within 0.2 systems.

  13. Determination of isocyanic acid in air.

    Science.gov (United States)

    Karlsson, D; Dalene, M; Skarping, G; Marand, A

    2001-08-01

    A method is presented for the determination of isocyanic acid (ICA), HNCO, in air samples as a di-n-butylamine (DBA) derivative. The method is based on sampling in midget impinger flasks containing 10 ml of 0.01 mol l-1 DBA in toluene. Quantification was made using liquid chromatography (LC) and electrospray mass spectrometry (MS) monitoring positive ions. The instrumental detection limit for the LC-MS was 10 fmol of ICA-DBA. ICA was generated by thermal decomposition of urea. A standard solution containing the DBA derivatives of ICA was prepared by collecting the emitted ICA in an impinger flask containing DBA. ICA in the reference solution was characterised by LC and time-of-flight (TOF) MS and quantified by LC chemiluminescent nitrogen detection (LC-CLND). The instrumental detection limit for the LC-CLND was 1 ng of nitrogen. ICA was emitted during thermal degradation of PFU resins and polyurethane (PUR) lacquers, from car metal sheets. ICA was the most dominant isocyanate and in PUR coating up to 8% of the total weight was emitted as ICA and for PFU resins up to 14% was emitted as ICA. When air samples were collected in an iron foundry during casting in sand moulds with furan resins, concentrations of ICA in the range 50-700 micrograms m-3 were found in the working atmosphere.

  14. Plasma Functionalized Multiwalled Carbon Nanotubes for Immobilization of Candida antarctica Lipase B: Production of Biodiesel from Methanolysis of Rapeseed Oil.

    Science.gov (United States)

    Rastian, Zahra; Khodadadi, Abbas Ali; Guo, Zheng; Vahabzadeh, Farzaneh; Mortazavi, Yadollah

    2016-03-01

    Surface modification of multiwalled carbon nanotubes (MWCNTs) through functionalization could improve the characteristics of these nanomaterials as support for enzymes. Carboxylation of MWCNTs (MWCNT-COOH) has been carried out in this study using the dielectric barrier discharge (DBD) plasma reactor through humidified air. The chemical method was also used for further functionalization of the MWCNT-COOH through which the amidation of the surfaces with either butylamine (MWCNT-BA) or octadecylamine (MWCNT-OA) was performed. By immobilization of Candida antarctica B lipase (CALB) on these nanoparticles, performance of the immobilized enzyme in catalyzing methanolysis of rapeseed oil was evaluated. The CALB loading on the MWCNT-BA and MWCNT-COOH was 20 mg protein/g, while the value for MWCNT-OA was 11 mg protein/g. The yield of biodiesel was determined as percentage of mass of fatty acid methyl ester (FAME) produced per initial mass of the oil, and the yield value for the two of these three supports namely, MWCNT-COOH and MWCNT-BA used for the CALB immobilization was similar at about 92 %, while 86 % was the yield for the reaction catalyzed by the lipase immobilized on MWCNT-OA. Thermal stability of the immobilized CALB and the catalytic ability of the enzyme in the repeated batch experiments have also been determined.

  15. Oxidation of amines by yeasts grown on 1-aminoalkanes or putrescine as the sole source of carbon, nitrogen and energy.

    Science.gov (United States)

    Middlehoven, W J; Hoogkamer-Te Niet, M C; De Laat, W T; Weijers, C; Bulder, C J

    1986-01-01

    The maximum growth rate of Trichosporon cutaneum CBS 8111 in chemostat cultures was 0.185 h-1 on ethylamine and 0.21 h-1 on butylamine, that of Candida famata CBS 8109 was 0.32 h-1 on putrescine. The amine oxidation pattern of the ascomycetous strains studied, viz. Candida famata CBS 8109, Stephanoascus ciferrii CBS 4856 and Trichosporon adeninovorans CBS 8244 was independent of the amine that had been used as the growth substrate. It resembled that of benzylamine/putrescine oxidase found in other ascomycetous yeasts. However, differences in pH optimum and substrate specificity were observed between the amine-oxidizing systems of these three species. The amine oxidation pattern of cell-free extracts of Trichosporon cutaneum CBS 8111 varied with the amine that was used as growth substrate. The enzyme system produced by Cryptococcus laurentii CBS 7140 failed to oxidize isobutylamine and benzylamine, and showed a high pH optimum. The synthesis of amine oxidase in the four yeast strains studied was not repressed by ammonium chloride and was weakly repressed by glucose but was strongly repressed if both compounds were present in the growth medium.

  16. Characterization of the microbial community structure and nitrosamine-reducing isolates in drinking water biofilters.

    Science.gov (United States)

    Wang, Wanfeng; Guo, Yanling; Yang, Qingxiang; Huang, Yao; Zhu, Chunyou; Fan, Jing; Pan, Feng

    2015-07-15

    Two biofilters were constructed using biological activated carbon (BAC) and nitrosamine-containing water from two drinking water treatment plants. The microbiome of each biofilter was characterized by 454 high-throughput pyrosequencing, and one nitrosamine-reducing bacterium was isolated. The results showed that nitrosamines changed the relative abundance at both the phylum and class levels, and the new genera were observed in the microbial communities of the two BAC filters after cultivation. As such, the genus Rhodococcus, which includes many nitrosamine-reducing strains reported in previous studies, was only detected in the BAC2 filter after cultivation. These findings indicate that nitrosamines can significantly affect the genus level in the microbial communities. Furthermore, the isolated bacterial culture Rhodococcus cercidiphylli A41 AS-1 exhibited the ability to reduce five nitrosamines (N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosodi-n-propylamine, N-nitrosopyrrolidine, and N-nitrosodi-n-butylamine) with removal ratios that ranged from 38.1% to 85.4%. The isolate exhibited a better biodegradation ability with nitrosamine as the carbon source when compared with nitrosamine as the nitrogen source. This study increases our understanding of the microbial community in drinking water biofilters with trace quantities of nitrosamines, and provides information on the metabolism of nitrosamine-reducing bacteria.

  17. Screening of reducing agents for the PEGylation of recombinant human IL-10.

    Science.gov (United States)

    Ambrogelly, Alexandre; Cutler, Collette; Paporello, Brittany

    2013-06-01

    PEGylation is a technology commonly used to enhance the bioavailability of therapeutic proteins in patients. Reductive alkylation of a protein amino terminal alpha amine in the presence of a polyethylene glycol (PEG) chain derivatized with propionaldehyde and a reducing agent, typically sodium cyanoborohydride, is one of the technologies available to achieve quantitative and site specific PEGylation. While cyanoborohydride has proven to be a robust and efficient reagent for this type of reaction, it generates aqueous cyanide as a reaction by-product (and its corollary, the very volatile hydrogen cyanide). We report here the screening of reducing agents such as dimethylamine borane, trimethylamine borane, triethylamine borane, tert-butylamine borane, morpholine borane, pyridine borane, 2-picoline borane, and 5-ethyl-2-methyl-pyridine borane as alternatives to cyanoborohydride for the PEGylation of recombinant human IL-10. The results of our study show that pyridine borane and 2-picoline borane promote rhIL-10 PEGylation at levels comparable to those observed with cyanoborohydride.

  18. Pure Cubic-Phase Hybrid Iodobismuthates AgBi2 I7 for Thin-Film Photovoltaics.

    Science.gov (United States)

    Kim, Younghoon; Yang, Zhenyu; Jain, Ankit; Voznyy, Oleksandr; Kim, Gi-Hwan; Liu, Min; Quan, Li Na; García de Arquer, F Pelayo; Comin, Riccardo; Fan, James Z; Sargent, Edward H

    2016-08-08

    Bismuth-based hybrid perovskites are candidates for lead-free and air-stable photovoltaics, but poor surface morphologies and a high band-gap energy have previously limited these hybrid perovskites. A new materials processing strategy to produce enhanced bismuth-based thin-film photovoltaic absorbers by incorporation of monovalent silver cations into iodobismuthates is presented. Solution-processed AgBi2 I7 thin films are prepared by spin-coating silver and bismuth precursors dissolved in n-butylamine and annealing under an N2 atmosphere. X-ray diffraction analysis reveals the pure cubic structure (Fd3m) with lattice parameters of a=b=c=12.223 Å. The resultant AgBi2 I7 thin films exhibit dense and pinhole-free surface morphologies with grains ranging in size from 200-800 nm and a low band gap of 1.87 eV suitable for photovoltaic applications. Initial studies produce solar power conversion efficiencies of 1.22 % and excellent stability over at least 10 days under ambient conditions.

  19. Ultrafast charge- and energy-transfer dynamics in conjugated polymer: cadmium selenide nanocrystal blends.

    Science.gov (United States)

    Morgenstern, Frederik S F; Rao, Akshay; Böhm, Marcus L; Kist, René J P; Vaynzof, Yana; Greenham, Neil C

    2014-02-25

    Hybrid nanocrystal-polymer systems are promising candidates for photovoltaic applications, but the processes controlling charge generation are poorly understood. Here, we disentangle the energy- and charge-transfer processes occurring in a model system based on blends of cadmium selenide nanocrystals (CdSe-NC) with poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene] (MDMO-PPV) using a combination of time-resolved absorption and luminescence measurements. The use of different capping ligands (n-butylamine, oleic acid) as well as thermal annealing allows tuning of the polymer-nanocrystal interaction. We demonstrate that energy transfer from MDMO-PPV to CdSe-NCs is the dominant exciton quenching mechanism in nonannealed blends and occurs on ultrafast time scales (<1 ps). Upon thermal annealing electron transfer becomes competitive with energy transfer, with a transfer rate of 800 fs independent of the choice of the ligand. Interestingly, we find hole transfer to be much less efficient than electron transfer and to extend over several nanoseconds. Our results emphasize the importance of tuning the organic-nanocrystal interaction to achieve efficient charge separation and highlight the unfavorable hole-transfer dynamics in these blends.

  20. Survivability and reactivity of glycine and alanine in early oceans: effects of meteorite impacts.

    Science.gov (United States)

    Umeda, Yuhei; Fukunaga, Nao; Sekine, Toshimori; Furukawa, Yoshihiro; Kakegawa, Takeshi; Kobayashi, Takamichi; Nakazawa, Hiromoto

    2016-01-01

    Prebiotic oceans might have contained abundant amino acids, and were subjected to meteorite impacts, especially during the late heavy bombardment. It is so far unknown how meteorite impacts affected amino acids in the early oceans. Impact experiments were performed under the conditions where glycine was synthesized from carbon, ammonia, and water, using aqueous solutions containing (13)C-labeled glycine and alanine. Selected amino acids and amines in samples were analyzed with liquid chromatography-mass spectrometry (LC/MS). In particular, the (13)C-labeled reaction products were analyzed to distinguish between run products and contaminants. The results revealed that both amino acids survived partially in the early ocean through meteorite impacts, that part of glycine changed into alanine, and that large amounts of methylamine and ethylamine were formed. Fast decarboxylation was confirmed to occur during such impact processes. Furthermore, the formation of n-butylamine, detected only in the samples recovered from the solutions with additional nitrogen and carbon sources of ammonia and benzene, suggests that chemical reactions to form new biomolecules can proceed through marine impacts. Methylamine and ethylamine from glycine and alanine increased considerably in the presence of hematite rather than olivine under similar impact conditions. These results also suggest that amino acids present in early oceans can contribute further to impact-induced reactions, implying that impact energy plays a potential role in the prebiotic formation of various biomolecules, although the reactions are complicated and depend upon the chemical environments as well.

  1. Linear energy relationships in ground state proton transfer and excited state proton-coupled electron transfer.

    Science.gov (United States)

    Gamiz-Hernandez, Ana P; Magomedov, Artiom; Hummer, Gerhard; Kaila, Ville R I

    2015-02-12

    Proton-coupled electron transfer (PCET) processes are elementary chemical reactions involved in a broad range of radical and redox reactions. Elucidating fundamental PCET reaction mechanisms are thus of central importance for chemical and biochemical research. Here we use quantum chemical density functional theory (DFT), time-dependent density functional theory (TDDFT), and the algebraic diagrammatic-construction through second-order (ADC(2)) to study the mechanism, thermodynamic driving force effects, and reaction barriers of both ground state proton transfer (pT) and photoinduced proton-coupled electron transfer (PCET) between nitrosylated phenyl-phenol compounds and hydrogen-bonded t-butylamine as an external base. We show that the obtained reaction barriers for the ground state pT reactions depend linearly on the thermodynamic driving force, with a Brønsted slope of 1 or 0. Photoexcitation leads to a PCET reaction, for which we find that the excited state reaction barrier depends on the thermodynamic driving force with a Brønsted slope of 1/2. To support the mechanistic picture arising from the static potential energy surfaces, we perform additional molecular dynamics simulations on the excited state energy surface, in which we observe a spontaneous PCET between the donor and the acceptor groups. Our findings suggest that a Brønsted analysis may distinguish the ground state pT and excited state PCET processes.

  2. STUDIES ON REVERSE OSMOSIS SEPARATION OF AQUEOUS ORGANIC SOLUTIONS BY PAA/PSF COMPOSITE MEMBRANE

    Institute of Scientific and Technical Information of China (English)

    Jun Fang; De-min Jia; Ji-cai Huang; Qun-hui Guo; Feng-lian Wu

    2000-01-01

    The reverse osmosis (RO) separation of aqueous organic solutions, such as alcohols, amines, aldehydes, acids,ketones, and esters etc., by PAA (polyacrylic acid)/PSF (polysulfone) composite membrane has been studied. It was found that the separation results for aliphatic alcohols, amines and aldehydes are satisfactory, the solute rejection (Ra) and the volume fluxes of solutions (Jr) for 1000 ppm ethanol, ethylamine and ethyl aldehyde are 66.2%, 61.0%, 84.0% and 0.90×alcohols, amines and aldehydes, and the Ra for n-amyl alcohol, n-butylamine and n-butyl aldehyde reached 94.3%, 88.6%and 96.0%, respectively. Satisfactory separation results (Ra>70%) for ketones, esters, phenols and polyols have been obtained with the PAA/PSF composite membrane. The effect of operating pressure on the properties of reverse osmosis has also been investigated. Analysis of experimental data with Spiegler-Kedem's transport model has been carried out and the membrane constants such as reflection coefficient σ, solute and hydraulic permeabilities ω and Lp for several organic solutes have been obtained.

  3. Volumetric Behavior of Binary Mixtures of Alkoxyethanols and Some Selected Amines at 298.15 K

    Directory of Open Access Journals (Sweden)

    Ayasen Jermaine Kemeakegha

    2015-01-01

    Full Text Available Densities of binary mixtures of 2-methoxyethanol (2-MeO-EtOH and 2-ethoxyethanol (2-EtO-EtOH with hexylamine (HLA, diethylamine (DEA, triethylamine (TEA, tert-butylamine (TBA, aniline (ANL, and benzylamine (BLA have been determined at varying compositions of the alkoxyalkanols at 298.15 K. The excess molar volumes, VE, of the binary mixtures were calculated from the experimental density data of the mixtures and the component single solvents. The calculated excess molar volumes were fitted into the Redlich-Kister polynomial to obtain the fitting coefficients and standard deviations. The excess molar volumes of the binary mixtures of all the solvent systems investigated were negative over the entire range of the solvents composition. The negative values were attributed to stronger hydrogen bond formations between the unlike molecules of mixtures than those between the like molecules of the pure components. The magnitude of the excess molar volumes of the binary mixtures of 2-methoxyethanol and the aliphatic amines were in the order TBA > TEA > DEA > HEA. For the two aromatic amines, the magnitudes were in the order BLA > ANL. For binary mixtures of the amines and 2-ethoxyethanol, the magnitudes were in the order DEA > TEA > TBA > HEA at compositions where the mole fraction of 2-EtO-EtOH was ≤0.5 and TBA > TEA > DEA > HEA above 0.5 mole fraction of 2-EtO-EtOH.

  4. Electrochemical characterization of platinum nanoparticles stabilized by amines

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez-Meneses, E., E-mail: esthervincent@yahoo.co [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, CICATA-IPN Unidad Altamira, Km 14.5 Carretera Tampico-Puerto Industrial, C.P. 89600 Altamira, Tamaulipas (Mexico); Dominguez-Crespo, M.A. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, CICATA-IPN Unidad Altamira, Km 14.5 Carretera Tampico-Puerto Industrial, C.P. 89600 Altamira, Tamaulipas (Mexico); Montiel-Palma, V. [Centro de Investigaciones Quimicas, Universidad Autonoma del Estado de Morelos, Av. Universidad 1001, Colonia Chamilpa, C.P. 62201 Cuernavaca, Morelos (Mexico); Chavez-Herrera, V.H. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, CICATA-IPN Unidad Altamira, Km 14.5 Carretera Tampico-Puerto Industrial, C.P. 89600 Altamira, Tamaulipas (Mexico); Gomez, E. [Instituto de Quimica-Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, C.P. 04510 Mexico, D.F. (Mexico); Hernandez-Tapia, G. [Gerencia de Catalizadores y Proceso, Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas norte 152, 07730 Mexico, D.F. (Mexico)

    2009-08-26

    In this work we present the synthesis by Chaudret approach of Pt nanoparticles stabilized by primary amine (-NH{sub 2}) compounds. Their electrochemical performance as cathodes in low temperature polymer electrolite fuel cells on the oxygen reduction reaction (ORR) is also presented. Transmission electron microscopy (TEM) images of the samples show Pt nanostructures with particle size varying from 10 to 100 nm depending on the kind of the stabilizer used during the catalyst preparation. In some cases well-dispersed isolated platinum nanoparticles were observed. The activity of the dispersed catalysts (Pt/C) with respect to the ORR was investigated using steady state polarization measurements. The kinetic parameters showed that although no significant differences between the Tafel slopes of the Pt catalysts exist, transfer coefficients and exchange current densities show higher activities when the Pt nanoparticles were stabilized by tert-butylamine (TBA). The performance with respect to the ORR of the Pt/C catalyst on vulcan carbon substrate is active and comparable to that reported in the literature for state-of-art electrocatalysts.

  5. NIOSH Manual of Analytical Methods (third edition). Fourth supplement

    Energy Technology Data Exchange (ETDEWEB)

    1990-08-15

    The NIOSH Manual of Analytical Methods, 3rd edition, was updated for the following chemicals: allyl-glycidyl-ether, 2-aminopyridine, aspartame, bromine, chlorine, n-butylamine, n-butyl-glycidyl-ether, carbon-dioxide, carbon-monoxide, chlorinated-camphene, chloroacetaldehyde, p-chlorophenol, crotonaldehyde, 1,1-dimethylhydrazine, dinitro-o-cresol, ethyl-acetate, ethyl-formate, ethylenimine, sodium-fluoride, hydrogen-fluoride, cryolite, sodium-hexafluoroaluminate, formic-acid, hexachlorobutadiene, hydrogen-cyanide, hydrogen-sulfide, isopropyl-acetate, isopropyl-ether, isopropyl-glycidyl-ether, lead, lead-oxide, maleic-anhydride, methyl-acetate, methyl-acrylate, methyl-tert-butyl ether, methyl-cellosolve-acetate, methylcyclohexanol, 4,4'-methylenedianiline, monomethylaniline, monomethylhydrazine, nitric-oxide, p-nitroaniline, phenyl-ether, phenyl-ether-biphenyl mixture, phenyl-glycidyl-ether, phenylhydrazine, phosphine, ronnel, sulfuryl-fluoride, talc, tributyl-phosphate, 1,1,2-trichloro-1,2,2-trifluoroethane, trimellitic-anhydride, triorthocresyl-phosphate, triphenyl-phosphate, and vinyl-acetate.

  6. Di-n-butylammonium 2-[(3,5-di-tert-butyl-4-hydroxybenzylsulfanyl]benzoate

    Directory of Open Access Journals (Sweden)

    Abeer A. Alhadi

    2010-09-01

    Full Text Available The title salt, C8H20N+·C22H27O3S−, is a proton-transfer compound derived from the recently reported parent carboxylic acid [Alhadi et al. (2010. Acta Cryst. E66, o1787] by the addition of a second equivalent of di-n-butylamine, yielding the di-n-butylammonium carboxylate salt. The structure of the carboxylate anion resembles that of the parent carboxylic acid. The main difference lies in the position of the H atom in the 4-hydroxy group. In the anion the O—H bond is perpendicular, rather than parallel, to the benzyl ring. This position appears to facilitate hydrogen bonding to an O atom of the carboxylate group of a symmetry-related anion. In addition, there are three N—H...O hydrogen bonds. In contrast, the neutral species hydrogen bonds via a carboxylic acid dimer. The dihedral angle between the benzene rings in the anion is 79.19 (7°.

  7. Ligand exchange in quaternary alloyed nanocrystals--a spectroscopic study.

    Science.gov (United States)

    Gabka, Grzegorz; Bujak, Piotr; Giedyk, Kamila; Kotwica, Kamil; Ostrowski, Andrzej; Malinowska, Karolina; Lisowski, Wojciech; Sobczak, Janusz W; Pron, Adam

    2014-11-14

    Exchange of initial, predominantly stearate ligands for pyridine in the first step and butylamine (BA) or 11-mercaptoundecanoic acid (MUA) in the second one was studied for alloyed quaternary Cu-In-Zn-S nanocrystals. The NMR results enabled us to demonstrate, for the first time, direct binding of the pyridine labile ligand to the nanocrystal surface as evidenced by paramagnetic shifts of the three signals attributed to its protons to 7.58, 7.95 and 8.75 ppm. XPS investigations indicated, in turn, a significant change in the composition of the nanocrystal surface upon the exchange of initial ligands for pyridine, which being enriched in indium in the 'as prepared' form became enriched in zinc after pyridine binding. This finding indicated that the first step of ligand exchange had to involve the removal of the surface layer enriched in indium with simultaneous exposure of a new, zinc-enriched layer. In the second ligand exchange step (replacement of pyridine with BA or MUA) the changes in the nanocrystal surface compositions were much less significant. The presence of zinc in the nanocrystal surface layer turned out necessary for effective binding of pyridine as shown by a comparative study of ligand exchange in Cu-In-Zn-S, Ag-In-Zn-S and CuInS2, carried out by complementary XPS and NMR investigations.

  8. The influence of the carrier molecule on amoxicillin recognition by specific IgE in patients with immediate hypersensitivity reactions to betalactams.

    Science.gov (United States)

    Ariza, Adriana; Mayorga, Cristobalina; Salas, María; Doña, Inmaculada; Martín-Serrano, Ángela; Pérez-Inestrosa, Ezequiel; Pérez-Sala, Dolores; Guzmán, Antonio E; Montañez, María I; Torres, María J

    2016-10-12

    The optimal recognition of penicillin determinants, including amoxicillin (AX), by specific IgE antibodies is widely believed to require covalent binding to a carrier molecule. The nature of the carrier and its contribution to the antigenic determinant is not well known. Here we aimed to evaluate the specific-IgE recognition of different AX-derived structures. We studied patients with immediate hypersensitivity reactions to AX, classified as selective or cross-reactors to penicillins. Competitive immunoassays were performed using AX itself, amoxicilloic acid, AX bound to butylamine (AXO-BA) or to human serum albumin (AXO-HSA) in the fluid phase, as inhibitors, and amoxicilloyl-poli-L-lysine (AXO-PLL) in the solid-phase. Two distinct patterns of AX recognition by IgE were found: Group A showed a higher recognition of AX itself and AX-modified components of low molecular weights, whilst Group B showed similar recognition of both unconjugated and conjugated AX. Amoxicilloic acid was poorly recognized in both groups, which reinforces the need for AX conjugation to a carrier for optimal recognition. Remarkably, IgE recognition in Group A (selective responders to AX) is influenced by the mode of binding and/or the nature of the carrier; whereas IgE in Group B (cross-responders to penicillins) recognizes AX independently of the nature of the carrier.

  9. Synthesis and characterization of zeolite Ti-V-ZSM-5 containing double heteroatoms%双杂原子Ti-V-ZSM-5分子筛的合成与表征

    Institute of Scientific and Technical Information of China (English)

    霍丽华; 赵经贵; 马淑杰

    2001-01-01

    The synthesis of zeolite Ti-V-ZSM-5 containing double heteroatoms with silica sol as Sisources, titanium sulfate and vandium oxisulfate as the starting materials and tetrapropyl ammonium bromide(TPABr), 1, 6-dihexamine(1,6-HDA) and n-butylamine as the templates, respectively was investigated for the first time in the absence of alkali metal ions. Some physical and chemical properties and the structure of the product were characterized by using XRD, SEM, TG-DTA, IR, UV-Vis spectra.%在无碱性离子存在下,以硅溶胶、硫酸钛、硫酸氧钒为原料,分别采用四丙基溴化胺(TPABr)、1,6-己二胺(1,6-HDA)及正丁胺(R-NH2)模板剂,首次合成了双杂原子Ti-V-ZSM-5分子筛,并对产物的物性与结构进行了表征。

  10. 双杂原子Ti-Mn-ZSM-5分子筛的合成与表征%Synthesis and characterization of zeolite Ti- Mn-ZSM-5 containing double heteroatoms

    Institute of Scientific and Technical Information of China (English)

    霍丽华; 赵经贵; 马淑杰

    2000-01-01

    在无碱性离子存在下,以硅溶胶、硫酸钛、硫酸锰为原料,分别采用四丙基溴化胺(TPABr)、1,6-己二胺(1,6-HDA)及正丁胺(R-NH2)模板剂,首次合成了双杂原子Ti-Mn-ZSM-5分子筛,并对产物的物性与结构进行了表征。%In the absence of alkali metal ions, the zeolite Ti-Mn-ZSM-5 containing double heteroatom, with silica sol as Si sources, titanium sulfate and manganese sulfate as the starting materials and tetrapropyl ammomium bromide(TPABr), 1, 6-dihexamine(l, 6-HDA) and n-butylamine (R-NH2) as the templates, respectively, was synthesized for the first time. Some physical and chemical properties and the structure of the product were characterized by using XRD, SEM, TG-DTA, IR and ESR methods.

  11. Electrodialytic membrane suppressors for ion chromatography make programmable buffer generators.

    Science.gov (United States)

    Chen, Yongjing; Srinivasan, Kannan; Dasgupta, Purnendu K

    2012-01-01

    The use of buffer solutions is immensely important in a great variety of disciplines. The generation of continuous pH gradients in flow systems plays an important role in the chromatographic separation of proteins, high-throughput pK(a) determinations, etc. We demonstrate here that electrodialytic membrane suppressors used in ion chromatography can be used to generate buffers. The generated pH, computed from first principles, agrees well with measured values. We demonstrate the generation of phosphate and citrate buffers using a cation-exchange membrane (CEM) -based anion suppressor and Tris and ethylenediamine buffers using an anion-exchange membrane (AEM) -based cation suppressor. Using a mixture of phosphate, citrate, and borate as the buffering ions and using a CEM suppressor, we demonstrate the generation of a highly reproducible (avg RSD 0.20%, n = 3), temporally linear (pH 3.0-11.9, r(2) > 0.9996), electrically controlled pH gradient. With butylamine and a large concentration (0.5 M) of added NaCl, we demonstrate a similar linear pH gradient of large range with a near-constant ionic strength. We believe that this approach will be of value for the generation of eluents in the separation of proteins and other biomolecules and in online process titrations.

  12. MOCVD of hexagonal boron nitride thin films on Si(100) using new single source precursors

    CERN Document Server

    Boo, J H; Yu, K S; Kim, Y S; Kim, Y S; Park, J T

    1999-01-01

    We have been carried out the growth of hexagonal boron nitride (h-BN) thin films on Si(100) substrates by low pressure metal-organic chemical vapor deposition (LPMOCVD) method using triethylborane tert-butylamine complex (TEBTBA), Et sub 3 BNH sub 2 ( sup t Bu), and triethylborane isopropylamine complex (TEBIPA), Et sub 3 BNH sub 2 ( sup t Pr) as a new single molecular precursors in the temperature range of 850 approx 1000 .deg. C. polycrystalline, crack-free h-BN film was successfully grown on Si(100) substrate at 850 .deg. C using TEBTBA. This growth temperature is very lower than those in previous reports. Carbon-rich polycrystalline BN was also obtained at 900 .deg. C from TEBIPA. With increasing substrate temperature to 1000 .deg. C, however, BC sub 4 N-like species are strongly formed along with h-BN and the BN films obtained from both TEBTBA and TEBIPA but almost polycrystalline. To our best knowledge, this is the first report of the growth of h-BN films formed with the new single source precursors of ...

  13. Separation and conductimetric detection of C1-C7 aliphatic monocarboxylic acids and C1-C7 aliphatic monoamines on unfunctionized polymethacrylate resin columns.

    Science.gov (United States)

    Ohta, Kazutoku; Towata, Atsuya; Ohashi, Masayoshi; Takeuchi, Toyohide

    2004-06-11

    The application of unfunctionized polymethacrylate resin (TSKgel G3000PWXL) as a stationary phase in liquid chromatography with conductimetric detection for C1-C7 aliphatic monocarboxylic acids (formic acid, acetic acid, propionic acid, butyric acid, isovaleric acid, valeric acid, 3,3-dimethylbutyric acid, 4-methylvaleric acid, hexanoic acid, 2-methylhexanoic acid, 5-methylhexanoic acid and heptanoic acid) and C1-C7 aliphatic monoamines (methylamine, ethylamine, propylamine, isobutylamine, butylamine, isoamylamine, amylamine, 1,3-dimethylbutylamine, hexylamine, 2-heptylamine and heptylamine) was attempted with C8 aliphatic monocarboxylic acids (2-propylvaleric acid, 2-ethylhexanoic acid, 2-methylheptanoic acid and octanoic acid) and C8 aliphatic monoamines (1,5-dimethylhexylamine, 2-ethylhexylamine, 1-methylheptylamine and octylamine) as eluents, respectively. Using 1 mM 2-methylheptanoic acid at pH 4.0 as the eluent, excellent separation and relatively high sensitive detection for these C1-C7 carboxylic acids were achieved on a TSKgel G3000PWXL column (150 mm x 6 mm i.d.) in 60 min. Using 2 mM octylamine at pH 11.0 as the eluent, excellent separation and relatively high sensitive detection for these C1-C7 amines were also achieved on the TSKgel G3000PWXL column in 60 min.

  14. Acetaldehyde behavior over platinum based catalyst in hydrogen stream generated by ethanol reforming

    Energy Technology Data Exchange (ETDEWEB)

    de Lima, Adriana F.F. [Laboratorio de Catalise, Instituto Nacional de Tecnologia, Av. Venezuela 82/507, 20081-310 Rio de Janeiro, RJ (Brazil); Instituto de Quimica e INOG (Instituto Nacional de Oleo Gas), UERJ-CNPq, FAPERJ, Universidade do Estado do Rio de Janeiro, Rua Sao Francisco Xavier, 524, 20550-900 Rio de Janeiro, RJ (Brazil); Colman, Rita C. [Departamento de Engenharia Quimica e de Petroleo, Universidade Federal Fluminense, Av. Passos da Patria, 156/bl E/240, 24210-240 Niteroi, RJ (Brazil); Zotin, Fatima M.Z. [Instituto de Quimica e INOG (Instituto Nacional de Oleo Gas), UERJ-CNPq, FAPERJ, Universidade do Estado do Rio de Janeiro, Rua Sao Francisco Xavier, 524, 20550-900 Rio de Janeiro, RJ (Brazil); CETEM-MCT, Av. Pedro Calmon, 900, Cidade Universitaria, 21941-908 Rio de Janeiro, RJ (Brazil); Appel, Lucia G. [Laboratorio de Catalise, Instituto Nacional de Tecnologia, Av. Venezuela 82/507, 20081-310 Rio de Janeiro, RJ (Brazil)

    2010-12-15

    Due to the greenhouse effect, hydrogen production from bioethanol reforming is a very important subject in heterogeneous catalysis research. Pt based catalysts are employed in H{sub 2} purification processes and also as electrocatalysts of PEM (''Proton Exchange Membrane'') fuel cells. Hydrogen obtained from ethanol reforming may contain, as contaminants, acetaldehyde and small amounts of CO. This aldehyde can be decarbonylated on Pt based catalysts generating carbon monoxide and methane, rendering the hydrogen purification more challenging. Moreover, acetaldehyde might also change the electrocatalyst behavior. Therefore, this contribution aims at studying the acetaldehyde behavior in the presence of platinum based catalysts in hydrogen atmosphere. The Pt/SiO{sub 2}, Pt/USY catalysts and an electrocatalyst were characterized by n-butylamine, H{sub 2} and CO{sub 2} adsorption, ATG/DTG measurements and cyclohexane dehydrogenation reaction. It was observed that the acid-basic properties of the supports promote condensation reactions. When in contact with Pt based catalysts, acetaldehyde undergoes C-C and C=O bond scissions. The former occurs at a wide range of temperatures, whereas the latter only at low temperatures (<200 C). The C-C bond scission (decarbonylation) produces methane and CO. The C=O bond scission generates carbon residues on the catalyst as well as oxygen species, which in turn is able to eliminate CO from the catalytic surface. The data also show that decarbonylation is not a structure-sensitive reaction. (author)

  15. Crystal structure of poly[bis(ammonium [bis(μ4-benzene-1,3,5-tricarboxylatodizincate] 1-methylpyrrolidin-2-one disolvate

    Directory of Open Access Journals (Sweden)

    Carlos Ordonez

    2016-05-01

    Full Text Available The title three-dimensional metal–organic framework (MOF compound, {(NH42[Zn2(C9H3O62]·2C5H9NO}n, features an anionic framework constructed from Zn2+ cations and benzene-1,3,5-tricarboxylate (BTC organic anions. Charge balance is achieved by outer sphere ammonium cations formed by degradation of di-n-butylamine in the solvothermal synthesis of the compound. Binuclear {Zn2(COO2} entities act as the framework's secondary building units. Each ZnII atom has a tetrahedral coordination environment with an O4 set of donor atoms. The three-dimensional framework adopts a rutile-type topology and channels are filled in an alternating fashion with ordered and disordered 1-methylpyrrolidin-2-one solvent molecules and ammonium cations. The latter are held in the channels via four N—H...O hydrogen bonds, including three with the benzene-1,3,5-tricarboxylate ligands of the anionic framework and one with a 1-methylpyrrolidin-2-one solvent molecule.

  16. Amine-functionalized, multi-arm star polymers: A novel platform for removing glyphosate from aqueous media.

    Science.gov (United States)

    Samuel, Lianna; Wang, Ran; Dubois, Geraud; Allen, Robert; Wojtecki, Rudy; La, Young-Hye

    2017-02-01

    We describe a novel method for efficiently removing glyphosate from aqueous media via adsorption onto highly functionalized star-shaped polymeric particles. These particles have a polystyrene core with more than 35 attached methacrylate polymer arms, each containing a plurality of pendant amines (poly(dimethylamino ethyl methacrylate): PDMAEMA) that are partially protonated in water. Kinetic studies demonstrate that these star-polymers successfully remove up to 93% of glyphosate present in aqueous solution (feed concentration: 5 ppm), within 10 min contact time, outperforming activated carbon, which removed 33% after 20 min. On these star-polymers, glyphosate adsorption closely follows the Langmuir model indicating monolayer coverage at most. Ionic interaction between the protonated amines and glyphosate's dissociated carboxylic and phosphoric acid groups lead to effective glyphosate capture even at feed concentrations below 1 ppm. Surface charge of these star polymers and dissociation of glyphosate are both influenced by pH, thus glyphosate removal efficiency increases from 63% to 93% when pH increases from 4.2 to 7.7. NMR studies conducted with butylamine as a proxy for these polymeric particles confirm that the amine group binds with both glyphosate's carboxylic and phosphoric acid groups when its concentrations are in a 2:1 or higher molar ratio with glyphosate.

  17. Synthesis of ZnS hollow nanospheres with holes using different amine templates

    Institute of Scientific and Technical Information of China (English)

    Eingang LI; Yu TANG; Yuanming ZHANG; Jun YANG; Biying DU

    2008-01-01

    ZnS hollow nanospheres with holes were prepared by reacting ZnSO4 with H2S, the sulfide source formed in the reaction of CS2 with ethylenediamine, 1,3-propylenediamine, butylamine or 2-(2-aminoethylamino) ethanol, which also acted as a template agent, at 50℃ under agitation. The shape, particle size of about 100-850 nm and hole size of about 150-600 nm of ZnS hollow nanospheres with holes were shown by SEM and TEM images. These ZnS nanospheres with β cubic ZnS phase and composed of 2-5 nm nanocrystals were characterized by XRD and HRTEM. The blue shift of maximum absorption in UV-vis displayed the effect of quantum size. The two amino groups of amine templates reacted favorably with Zn2+ to form uniform and relatively smooth ZnS nanospheres with holes, while hydroxyethyl played a disadvantageous role. A reason-able mechanism of hole formation by H2S rushing out is suggested.

  18. Development of a Validated LC Method for Separation of Process-Related Impurities Including the R-Enantiomer of S-Pramipexole on Polysaccharide Chiral Stationary Phases.

    Science.gov (United States)

    Ramisetti, Nageswara Rao; Kuntamukkala, Ramakrishna; Arnipalli, Manikanta Swamy

    2015-07-01

    Despite the availability of a few methods for individual separation of S-pramipexole from its process-related impurities, no common liquid chromatography (LC) method is reported so far in the literature. The present article describes the development of a single-run LC method for simultaneous determination of S-pramipexole and its enantiomeric and process-related impurities on a Chiralpak AD-H (150 x 4.6 mm, 5μm) column using n-hexane/ethanol/n-butylamine (75:25:0.1 v/v/v) as a mobile phase in an isocratic mode of elution at a flow rate of 1.2 ml/min at 30°C. The chromatographic eluents were monitored at a wavelength of 260 nm using a photodiode array detector. Excellent enantioseparation with good resolutions (Rs ≥ 2.88) and peak shapes (As ≤ 1.21) for all analytes was achieved. The proposed method was validated according to International Conference Harmonization (ICH) guidelines in terms of accuracy, precision, sensitivity, and linearity. Limits of quantification of impurities (0.25-0.55 μg/ml) indicate the highest sensitivity achievable by the proposed method. The method has an advantage of selectivity and suitability for routine determination of not only chiral impurity but also all possible related substances in active pharmaceutical ingredients of S-pramipexole.

  19. Silver-coated magnetite-carbon core-shell microspheres as substrate-enhanced SERS probes for detection of trace persistent organic pollutants.

    Science.gov (United States)

    An, Qiao; Zhang, Peng; Li, Jun-Mei; Ma, Wan-Fu; Guo, Jia; Hu, Jun; Wang, Chang-Chun

    2012-08-21

    Highly active surface-enhanced Raman scattering (SERS) substrates of Ag nanoparticle (Ag-NP) modified Fe(3)O(4)@carbon core-shell microspheres were synthesized and characterized. The carbon coated Fe(3)O(4) microspheres were prepared via a one-pot solvothermal method and were served as the magnetic supporting substrates. The Ag-NPs were deposited by in situ reduction of AgNO(3) with butylamine and the thickness of the Ag-NP layer was variable by controlling the AgNO(3) concentrations. The structure and integrity of the Fe(3)O(4)@C@Ag composite microspheres were confirmed by TEM, XRD, VSM and UV-visible spectroscopy. In particular, the Ag-NP coated Fe(3)O(4)@carbon core-shell microspheres were shown to be highly active for SERS detections of pentachlorophenol (PCP), diethylhexyl phthalate (DEHP) and trinitrotoluene (TNT). These analytes are representatives of environmentally persistent organic pollutants with typically low SERS activities. The results suggested that the interactions between the carbon on the microsphere substrates and the aromatic cores of the target molecules contributed to the facile pre-concentration of the analytes near the Ag-NP surfaces.

  20. Positronium formation in various polyimides

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Ken-ichi; Tanaka, Kazuhiro; Katsube, Mikio; Sueoka, Osamu; Ito, Yasuo (Yamaguchi Univ., Ube (Japan). Faculty of Engineering Tokyo Univ. (Japan). Research Center for Nuclear Science and Technology)

    1993-03-01

    Positronium (Ps) formation in various polyimides has been studied. It has been found that Ps yield is zero or small in the polyimides having pyromellitic dianhydride (PMDA) and 3,3[sup '],4,4[sup ']-benzophenonetetracarboxylic dianhydride (BTDA) as acid anhydride moiety, while those having 3,3[sup '],4,4[sup ']-biphenyltetracarboxylic dianhydride (BPDA) and 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) form Ps with intensities up to about 20%. This difference is well correlated with the electron affinity of these moieties: PMDA > BTDA > BPDA [approx] 6FDA. In another experiment o-Ps yields and its lifetimes were measured in benzene solutions of monomeric model compounds (imide compounds prepared from n-butylamine and the acid anhydrides). It has been found that the model compounds from PMDA and BTDA both inhibit Ps formation and quench o-Ps lifetimes but that those from BPDA and 6FDA have neither the inhibition nor the quenching effects. The results show that the spur model is applicable for Ps formation in the polyimides. (Author).

  1. Positronium formation in various polyimides

    Science.gov (United States)

    Okamoto, Ken-ichi; Tanaka, Kazuhiro; Katsube, Mikio; Sueoka, Osamu; Ito, Yasuo

    1993-03-01

    Positronium (Ps) formation in various polyimides has been studied. It has been found that Ps yield is zero or small in the polyimides having pyromellitic dianhydride (PMDA) and 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA) as acid anhydride moiety, while those having 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA) and 2,2- bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) form Ps with intensities up to about 20%. This difference is well correlated with the electron affinity of these moieties: PMDA > BTDA > BPDA ˜ 6FDA. In another experiment o-Ps yields and its lifetimes were measured in benzene solutions of monomeric model compounds (imide compounds prepared from n-butylamine and the acid anhydrides). It has been found that the model compounds from PMDA and BTDA both inhibit Ps formation and quench o-Ps lifetimes but that those from BPDA and 6FDA have neither the inhibition nor the quenching effects. The results show that the spur model is applicable for Ps formation in the polyimides.

  2. Efficient Visible Electroluminescence from Porous Silicon Diodes Passivated by Carbon Films

    Institute of Scientific and Technical Information of China (English)

    李宏建; 彭景翠; 瞿述; 颜永红; 许雪梅; 赵楚军

    2002-01-01

    By using n-butylamine as a carbon resource, carbon film is deposited on the p-n porous silicon (PS) surface with aradio-frequency glow discharge plasma system. Raman spectra and infrared reflection (IR) spectra of the carbonfilms indicate that there are amine-group and hydrogen atoms therein. The IR spectra of the passivated PSsamples exhibit that the PS surfaces are mainly covered with Si-C, Si-N and Si-O bonds. Electroluminescence(EL) spectra show that the EL intensity of the passivated PS diodes increases greatly and the blueshift of theEL peak occurs compared with the diodes without treatment. Both of these are stable while the passivateddiodes are exposed to the air indoors. The I-V characteristics reveal that the passivated diodes have a smallerseries resistance and a lower onset voltage. The influence of the carbon film passivation on EL properties of PShas also been discussed. The results have proven that carbon film passivation is a good way to enhance the PSluminescent intensity and stability.

  3. Synthesis and physicochemical characterization of titanium oxide and sulfated titanium oxide obtained by thermal hydrolysis of titanium tetrachloride

    Directory of Open Access Journals (Sweden)

    H. Esteban Benito

    2014-09-01

    Full Text Available This work reports the synthesis of titanium oxide (TiO2 and sulfated titanium oxide (TiO2-SO4(2- obtained by thermal hydrolysis of titanium tetrachloride. Titanium hydroxide synthesized by this method was impregnated with a 1 N H2SO4 solution, to give amounts of sulfate ions (SO4(2- of 3 and 7 wt%. The synthesized samples were dried at 120 °C during 24 h and then calcined for 3 h at 400 °C. Thermal analyses, X-ray diffraction, nitrogen physisorption, infrared spectroscopy, potentiometric titration with n-butylamine, U.V.-visible diffuse reflectance spectroscopy and scanning electron microscopy were used to characterize the materials. The results of physicochemical characterization revealed that a mixture of crystalline structures, anatase, brookite and rutile developed in the titanium oxide, stabilizing the anatase structure in the sulfated titanium oxides, and coexisting with a small amount of brookite structure. The synthesized mesoporous materials developed specific surface areas between 62 and 70 m² g-1, without detecting an important influence of sulfation on this parameter. The presence of sulfate ions improved the acidity of titanium oxide and modified the characteristics of light absorption in the 425-600 nm region, which suggests the possibility of using these materials in reactions assisted by visible light.

  4. Effect of membranes with various hydrophobic/hydrophilic properties on lipase immobilized activity and stability.

    Science.gov (United States)

    Chen, Guan-Jie; Kuo, Chia-Hung; Chen, Chih-I; Yu, Chung-Cheng; Shieh, Chwen-Jen; Liu, Yung-Chuan

    2012-02-01

    In this study, three membranes: regenerated cellulose (RC), glass fiber (GF) and polyvinylidene fluoride (PVDF), were grafted with 1,4-diaminobutane (DA) and activated with glutaraldehyde (GA) for lipase covalent immobilization. The efficiencies of lipases immobilized on these membranes with different hydrophobic/hydrophilic properties were compared. The lipase immobilized on hydrophobic PVDF-DA-GA membrane exhibited more than an 11-fold increase in activity compared to its immobilization on a hydrophilic RC-DA-GA membrane. The relationship between surface hydrophobicity and immobilized efficiencies was investigated using hydrophobic/hydrophilic GF membranes which were prepared by grafting a different ratio of n-butylamine/1,4-diaminobutane (BA/DA). The immobilized lipase activity on the GF membrane increased with the increased BA/DA ratio. This means that lipase activity was exhibited more on the hydrophobic surface. Moreover, the modified PVDF-DA membrane was grafted with GA, epichlorohydrin (EPI) and cyanuric chloride (CC), respectively. The lipase immobilized on the PVDF-DA-EPI membrane displayed the highest specific activity compared to other membranes. This immobilized lipase exhibited more significant stability on pH, thermal, reuse, and storage than did the free enzyme. The results exhibited that the EPI modified PVDF is a promising support for lipase immobilization.

  5. Performance of amines as silanol suppressors in reversed-phase liquid chromatography.

    Science.gov (United States)

    Calabuig-Hernández, S; García-Alvarez-Coque, M C; Ruiz-Angel, M J

    2016-09-23

    In reversed-phase liquid chromatography, cationic basic compounds yield broad and asymmetrical peaks, as a result of their ionic interaction with the anionic free silanol groups present in the silica-based stationary phases (commonly derivatised with C18 groups). A simple way to improve the peak shape is the addition to the hydro-organic mobile phase of a reagent (usually called additive) with cationic character. This associates with the stationary phase to prevent the access of analytes to the free silanol groups. Cationic additives may interact electrostatically with the anionic silanols. The hydrophobic region of the additive may also associate with the alkyl chains bound to the stationary phase, with the positive charge oriented towards the mobile phase. The access to the silanol groups is thus blocked, but in turn, the stationary phase is positively charged and will repel the protonated basic compounds, which unless their polarity is sufficiently low, will elute at very short times. In this work, a comparative study of the performance of a group of amines (butylamine, pentylamine, hexylamine, cyclopentylamine, cycloheptylamine, N,N-dimethyloctylamine and tributylmethylammonium chloride), as modifiers of the chromatographic behaviour of basic compounds, is carried out. The behaviour is compared with that obtained with the ionic liquids 1-butyl-3-methylimidazolium chloride and 1-hexyl-3-methylimidazolium chloride, used as additives. The study revealed that the performance of the cationic additives to block the silanol activity is mainly explained by the additive size and its ability to be adsorbed onto the stationary phase.

  6. Corrosion Inhibition Effect of Aliphatic Amines on Aluminum in HCl Solution%盐酸介质中脂肪胺类化合物对铝材的缓蚀作用

    Institute of Scientific and Technical Information of China (English)

    帅长庚; 邓淑珍; 宋玉苏; 银继伟

    2001-01-01

    用失重法和电化学方法研究了正丁胺、二乙胺、乌洛托品在1.0 mol/L HCl中对铝的缓蚀作用,并对其机理进行了探讨。研究结果表明:起初,3种化合物对铝均具有缓蚀作用,缓蚀效果:乌洛托品>二乙胺>正丁胺,随着时间的延长,缓蚀效率逐渐降低;3种化合物均为吸附型缓蚀剂,对铝腐蚀的阴极过程和阳极过程都有一定的抑制作用,其吸附符合兰格缪尔等温吸附方程。%The corrosion inhibition effect of aliphatic amines on industrial pure aluminum in 1.0 mol/L HCl solution was investigated by weightloss and electrochemical methods. The inhibition efficiency was found to decrease in following order hexamethylenetetramine >diethylamine>nbutylamine. The thermodynamic functions of adsorption ΔG0am and corrosion potential Ek were evaluated. The authors pointed out that the adsorption of amines followed Langmuir isothermal equation.

  7. Synthesis and characterization of Fe3O4@Ag core-shell: structural, morphological, and magnetic properties

    Directory of Open Access Journals (Sweden)

    Mahdi Ghazanfari

    2014-12-01

    Full Text Available This paper is a report on the synthesis of the Fe3O4@Ag core-shell with high saturation magnetization of magnetite nanoparticles as the core, by using polyol route and silver shell by chemical reduction. X-ray diffraction (XRD and Fourier transform infrared spectroscopy analyses confirmed that the particles so produced were monophase. The magnetic properties of the product were investigated by using a vibrating sample magnetometer. Magnetic saturation of magnetite was 91 emu/g that around about bulk magnetization. This high saturation magnetization can be attributed to the thin dead layer. By using polyethylene glycol as a surfactant to separate and restrict the growth of the particles, magnetostatic interactions are in good agreement with the remanence ratio analysis. Morphology and the average size of the particles were determined with field emission scanning electron microscope (FESEM. Spherical aggregates of Fe3O4 (size around 73 nm are composed of a small primary particle size of about 16 nm. Silver deposition was done using butylamine as the reductant of AgNO3 in ethanol with different ratio. The silver layers were estimated using statistical histogram images of FESEM. Silver-coated iron oxide nanohybrids have been used in a broad range of applications, including chemical and biological sensing, due to the broad absorption in the optical region associated with localized surface plasmon resonance.

  8. EFFECT OF VARIOUS PRETREATMENTS OF OIL PALM EMPTY FRUIT BUNCH FIBRES FOR SUBSEQUENT USE AS SUBSTRATE ON THE PERFORMANCE OF CELLULASE PRODUCTION BY ASPERGILLUS TERREUS

    Directory of Open Access Journals (Sweden)

    Mahdi Shahriarinour

    2011-02-01

    Full Text Available The possibility of using treated oil palm empty fruit bunch (OPEFB fibres as substrate for cellulase production by Aspergillus terreus was studied using shaking flask fermentation. The effect of different chemical pretreatments, i.e. formic acid, acetic acid, propylamine, phosphoric acid, and n-butylamine, on the suitability of OPEFB fibres as fermentation substrate was investigated. The findings revealed that pretreatment with these chemicals significantly (P<0.05 increased the cellulose and reduced the lignin contents prior to enzymatic hydrolysis. However, fermentation using OPEFB fibres pretreated with phosphoric acid gave the highest cellulase production, which was related to high cellulose content. Further improvement in cellulase production was obtained when the chemically pretreated OPEFB fibres were subsequently treated hydrothermally (autoclaved at 160oC for 10 min and then biologically (using effective microorganisms. The final activity of the three main components of cellulase (FPase, CMCase, and β-glucosidase obtained in fermentation by A. terreus using optimally treated OPEFB fibres was (0.77 U mL−1, 8.5 U mL-1, and 6.1 U mL-1, respectively. The production of all these three major components of cellulase using pretreated OPEFB fibres (i.e. chemical, hydrothermal, and biological were about three times higher than those obtained from fermentation using untreated OPEFB fibres.

  9. Synthesis of a resin monomer-soluble polyrotaxane crosslinker containing cleavable end groups.

    Science.gov (United States)

    Seo, Ji-Hun; Nakagawa, Shino; Hirata, Koichiro; Yui, Nobuhiko

    2014-01-01

    A resin monomer-soluble polyrotaxane (PRX) crosslinker with cleavable end groups was synthesized to develop degradable photosetting composite resins. The PRX containing 50 α-cyclodextrins (α-CDs) with disulfide end groups was initially modified with n-butylamine to obtain a resin monomer-soluble PRX. The PRX containing 13 n-butyl groups per α-CD molecule was completely soluble in conventional resin monomers such as 2-hydroxyethyl methacrylate (HEMA) and urethane dimethacrylate (UDMA). The synthesized n-butyl-containing PRX was further modified with 2-aminoethyl methacrylate to provide crosslinkable acrylic groups onto PRX. The prepared resin monomer-soluble PRX crosslinker was successfully polymerized with a mixture of HEMA and UDMA to provide photosetting plastic. It was confirmed that the Vickers hardness of the prepared plastic was greatly decreased after treatment with dithiothreitol. This indicates that the resin monomer-soluble PRX crosslinker can be applied to design degradable photosetting plastics potentially used in the industrial or biomedical field.

  10. Synthesis of a resin monomer-soluble polyrotaxane crosslinker containing cleavable end groups

    Directory of Open Access Journals (Sweden)

    Ji-Hun Seo

    2014-11-01

    Full Text Available A resin monomer-soluble polyrotaxane (PRX crosslinker with cleavable end groups was synthesized to develop degradable photosetting composite resins. The PRX containing 50 α-cyclodextrins (α-CDs with disulfide end groups was initially modified with n-butylamine to obtain a resin monomer-soluble PRX. The PRX containing 13 n-butyl groups per α-CD molecule was completely soluble in conventional resin monomers such as 2-hydroxyethyl methacrylate (HEMA and urethane dimethacrylate (UDMA. The synthesized n-butyl-containing PRX was further modified with 2-aminoethyl methacrylate to provide crosslinkable acrylic groups onto PRX. The prepared resin monomer-soluble PRX crosslinker was successfully polymerized with a mixture of HEMA and UDMA to provide photosetting plastic. It was confirmed that the Vickers hardness of the prepared plastic was greatly decreased after treatment with dithiothreitol. This indicates that the resin monomer-soluble PRX crosslinker can be applied to design degradable photosetting plastics potentially used in the industrial or biomedical field.

  11. Synthesis and characterization of molybdenum incorporated mesoporous aluminophosphate

    Science.gov (United States)

    Ho, Li-Ngee; Ikegawa, Tasuku; Nishiguchi, Hiroyasu; Nagaoka, Katsutoshi; Takita, Yusaku

    2006-07-01

    A synthesis of molybdenum incorporated mesoporous aluminophosphate with long-chain n-alkylamine as template material had been prepared under non-aqueous condition. These materials were extensively characterized by using X-ray diffraction (XRD), nitrogen sorption isotherms, nuclear magnetic resonance of 27Al and 31P (NMR), inductive coupled plasma (ICP), electron spin resonance (ESR), Fourier transform infrared (FTIR) and thermogravimetric-differential thermal analysis (TG-DTA). Morphology of the materials had been observed by using transmission electron microscope (TEM) that revealed the mesoporous materials possessed wormhole-like structures. Alkaline solvent extraction using n-butylamine/ethanol had been efficiently removed the n-alkylamine from the mesoporous samples which yielded BET surface areas around 550-730 m 2/g. BJH analysis showed a narrow pore size distribution which increased with increasing of the carbon chain length of alkylamine (template). Valence state and coordination of the molybdenum in the obtained samples were investigated by using ESR and FTIR where it was found that Mo 4+ and Mo 6+ molybdenum species existed in the molybdenum incorporated mesoporous aluminophosphate in tetrahedral coordination.

  12. Biosynthesis of amorphous mesoporous aluminophosphates using yeast cells as templates

    Energy Technology Data Exchange (ETDEWEB)

    Sifontes, Ángela B., E-mail: asifonte@ivic.gob.ve [Centro de Química, Instituto Venezolano de Investigaciones Científicas, Apartado 20632, Caracas 1020-A (Venezuela, Bolivarian Republic of); González, Gema [Centro de Ingeniería de Materiales y Nanotecnología, Instituto Venezolano de Investigaciones Científicas, Apartado 20632, Caracas 1020-A (Venezuela, Bolivarian Republic of); Tovar, Leidy M.; Méndez, Franklin J. [Centro de Química, Instituto Venezolano de Investigaciones Científicas, Apartado 20632, Caracas 1020-A (Venezuela, Bolivarian Republic of); Gomes, Maria E. [Centro de Ingeniería de Materiales y Nanotecnología, Instituto Venezolano de Investigaciones Científicas, Apartado 20632, Caracas 1020-A (Venezuela, Bolivarian Republic of); Cañizales, Edgar [Área de Análisis Químico Inorgánico, PDVSA, INTEVEP, Los Teques 1070-A (Venezuela, Bolivarian Republic of); Niño-Vega, Gustavo; Villalobos, Hector [Centro de Microbiología y Biología Celular, Instituto Venezolano de Investigaciones Científicas, Apartado 20632, Caracas 1020-A (Venezuela, Bolivarian Republic of); Brito, Joaquin L. [Centro de Química, Instituto Venezolano de Investigaciones Científicas, Apartado 20632, Caracas 1020-A (Venezuela, Bolivarian Republic of)

    2013-02-15

    Graphical abstract: Display Omitted Highlights: ► Amorphous aluminophosphates can take place using yeast as template. ► A mesoporous material was obtained. ► The specific surface area after calcinations ranged between 176 and 214 m{sup 2} g{sup −1}. -- Abstract: In this study aluminophosphates have been synthesized from aluminum isopropoxide and phosphoric acid solutions using yeast cells as template. The physicochemical characterization was carried out by thermogravimetric analysis; X-ray diffraction; Fourier transform infrared; N{sub 2} adsorption–desorption isotherms; scanning electron microscopy; transmission electron microscopy and potentiometric titration with N-butylamine for determination of: thermal stability; crystalline structure; textural properties; morphology and surface acidity, respectively. The calcined powders consisted of an intimate mixture of amorphous and crystallized AlPO particles with sizes between 23 and 30 nm. The average pore size observed is 13–16 nm and the specific surface area after calcinations (at 650 °C) ranged between 176 and 214 m{sup 2} g{sup −1}.

  13. In situ crosslinked smart polypeptide nanoparticles for multistage responsive tumor-targeted drug delivery

    Science.gov (United States)

    Yi, Huqiang; Liu, Peng; Sheng, Nan; Gong, Ping; Ma, Yifan; Cai, Lintao

    2016-03-01

    Smart tumor-targeted drug delivery is crucial for improving the effect of chemotherapy and reducing the adverse effects. Here, we synthesized a smart polypeptide copolymer based on n-butylamine-poly(l-lysine)-b-poly(l-cysteine) (PLL-PLC) with functionalization of folic acid (FA) and 1,2-dicarboxylic-cyclohexene anhydride (DCA) for multistage responsive tumor-targeted drug delivery. The copolymers (FA-PLL(DCA)-PLC) spontaneously crosslinked in situ to form redox and pH dual responsive FA-PLL(DCA)-PLC nanoparticles (FD-NPs), which had a reversible zeta potential around -30 mV at pH 7.4, but switched to +15 mV at pH 5.0. Moreover, FD-NPs effectively loaded DOX with a loading capacity at 15.7 wt%. At pH 7.4, only 24.5% DOX was released within 60 h. However, at pH 5.0, the presence of 10 mM DTT dramatically accelerated DOX release with over 90% of DOX released within 10 h. Although the FD-NPs only enhanced DOX uptake in FA receptor positive (FR+) cancer cells at pH 7.4, a weak acidic condition promoted FD-NP-facilitated DOX uptake in both FR+ HeLa and FR- A549 cells, as well as significantly improving cellular binding and end/lysosomal escape. In vivo studies in a HeLa cancer model demonstrated that the charge-reversible FD-NPs delivered DOX into tumors more effectively than charge-irreversible nanoparticles. Hence, these multistage responsive FD-NPs would serve as highly efficient drug vectors for targeted cancer chemotherapy.Smart tumor-targeted drug delivery is crucial for improving the effect of chemotherapy and reducing the adverse effects. Here, we synthesized a smart polypeptide copolymer based on n-butylamine-poly(l-lysine)-b-poly(l-cysteine) (PLL-PLC) with functionalization of folic acid (FA) and 1,2-dicarboxylic-cyclohexene anhydride (DCA) for multistage responsive tumor-targeted drug delivery. The copolymers (FA-PLL(DCA)-PLC) spontaneously crosslinked in situ to form redox and pH dual responsive FA-PLL(DCA)-PLC nanoparticles (FD-NPs), which had a reversible

  14. PREPARATION AND ADSORPTION PROPERTIES OF BILIRUBIN ADSORBENTS WITH DIFFERENT LIGANDS BASED ON SEPHAROSE CL-4B%胆红素吸附剂功能基组成及其吸附特性研究

    Institute of Scientific and Technical Information of China (English)

    王智; 陈书博; 徐丽; 谢健; 贾凌云

    2011-01-01

    为了获得性能较佳的胆红素吸附剂,本研究考察了功能基种类、链长、偶联密度等因素对吸附剂吸附性能的影响.结果表明,当功能基具有足够的链长,与胆红素相似的疏水性及较高的偶联密度时,能够提高吸附剂的胆红素吸附能力.实验表明,链长21个原子、偶联73μmol/mL正丁胺的吸附剂对胆红素的吸附能力最强,在30℃、300mg/L的白蛋白结合胆红素溶液中,吸附1h即达到平衡,胆红素吸附量达到3.01 mg/mL (90.3mg/g干重);较高的温度有利于其对胆红素的吸附.50mL材料对500mL实际病人血浆动态吸附2.5h,总胆红素(277.4mg/L)去除率达到55.2%,同时对血浆蛋白的吸附较低.所有结果显示该吸附剂具有很强的实际应用的潜力.%A series of bilirubin adsorbents with different ligand type, length and density were prepared by activation of Sepharose CL-4B and their adsorption capacities to bilirubin were measured in static adsorption experiments. The results showed that the structure and properties of ligands, such as sufficient spacer-length, higher grafting density on the adsorbent and the similar hydrophobicity with bilirubin, were helpful to improve adsorption capacity of bilirubin. These experiments provided some ideas for designing new adsorbents. Among these adsorbents, the adsorbent with 73μmol/mL butylamine and 23-atom spacer showed the strongest adsorption ability to bilirubin in BSA-bilirubin solution, which could reach the adsorption balance at 30°C in lh, and got binding capacity of 3.01mg/mL gel. Moreover, higher temperature was more favorable to the adsorption of bilirubin. The in vitro hemoperfusion experiments were carried out by adding 50mL adsorbent into 500mL patient's plasma and 55.2% of bilirubin (277.4mg/L) was removed after 2.5h, and at the same time, adsorption for plasma proteins was low. These results indicated that the Butylamine-Sepharose adsorbents could be a potential choice for specific

  15. A Unique Equation to Estimate Flash Points of Selected Pure Liquids Application to the Correction of Probably Erroneous Flash Point Values

    Science.gov (United States)

    Catoire, Laurent; Naudet, Valérie

    2004-12-01

    several flash points have been reported erroneously, whatever the reason, in one or several reference compilations. In the following lists, the currently accepted flash points for bold compounds err, or probably err, on the hazardous side by at least 10 °C and for the nonbolded compounds, the currently accepted flash points err, or probably err, on the nonhazardous side by at least 10 °C: bicyclohexyl, sec-butylamine, tert-butylamine, 2-cyclohexen-1-one, ethanethiol, 1,3-cyclohexadiene, 1,4-pentadiene, methyl formate, acetonitrile, cinnamaldehyde, 1-pentanol, diethylene glycol, diethyl fumarate, diethyl phthalate, trimethylamine, dimethylamine, 1,6-hexanediol, propylamine, methanethiol, ethylamine, bromoethane, 1-bromopropane, tert-butylbenzene, 1-chloro-2-methylpropane, diacetone alcohol, diethanolamine, 2-ethylbutanal, and formic acid. For some other compounds, no other data than the currently accepted flash points are available. Therefore, it cannot be assessed that these flash point data are erroneous but it can be stated that they are probably erroneous. At least, they need experimental re-examination. They are probably erroneous by at least 15 °C: 1,3-cyclopentadiene, di-tert-butyl sulfide, dimethyl ether, dipropyl ether, 4-heptanone, bis(2-chloroethyl)ether, 1-decanol, 1-phenyl-1-butanone, furan, ethylcyclopentane, 1-heptanethiol, 2,5-hexanediol, 3-hexanone, hexanoic acid methyl ester, 4-methyl-1,3-pentadiene, propanoyl chloride, tetramethylsilane, thiacyclopentane, 1-chloro-2-methyl-1-propene, trans-1,3-pentadiene, 2,3-dimethylheptane, triethylenetetramine, methylal, N-ethylisopropylamine, 3-methyl-2-pentene, and 2,3-dimethyl-1-butene.

  16. TUNGSTOPHOSPHORIC ACID HETEROGENIZED ONTO NH4ZSM5 AS AN EFFICIENT AND RECYCLABLE CATALYST FOR THE PHOTOCATALYTIC DEGRADATION OF DYES

    Directory of Open Access Journals (Sweden)

    Candelaria Leal Marchena

    2015-05-01

    Full Text Available Materials based on tungstophosphoric acid (TPA immobilized on NH4ZSM5 zeolite were prepared by wet impregnation of the zeolite matrix with TPA aqueous solutions. Their concentration was varied in order to obtain TPA contents of 5%, 10%, 20%, and 30% w/w in the solid. The materials were characterized by N2 adsorption-desorption isotherms, XRD, FT-IR, 31P MAS-NMR, TGA-DSC, DRS-UV-Vis, and the acidic behavior was studied by potentiometric titration with n-butylamine. The BET surface area (SBET decreased when the TPA content was raised as a result of zeolite pore blocking. The X-ray diffraction patterns of the solids modified with TPA only presented the characteristic peaks of NH4ZSM5 zeolites, and an additional set of peaks assigned to the presence of (NH43PW12O40. According to the Fourier transform infrared and 31P magic angle spinning-nuclear magnetic resonance spectra, the main species present in the samples was the [PW12O40]3- anion, which was partially transformed into the [P2W21O71]6- anion during the synthesis and drying steps. The thermal stability of the NH4ZSM5TPA materials was similar to that of their parent zeolites. Moreover, the samples with the highest TPA content exhibited band gap energy values similar to those reported for TiO2. The immobilization of TPA on NH4ZSM5 zeolite allowed the obtention of catalysts with high photocatalytic activity in the degradation of methyl orange dye (MO in water, at 25 ºC. These can be reused at least three times without any significant decrease in degree of degradation.

  17. Synthesis and reactivity of cyclic-carbamate derivatives%环状氨基甲酸酯衍生物的合成及反应研究

    Institute of Scientific and Technical Information of China (English)

    王静; 郭爽; 王家喜

    2011-01-01

    Cyclic carbamate has been prepared by the reaction of ethanolamine with dimethyl carbonate as raw material and zinc acetate as catalyst. The cyclic carbamate reacted with methyl acrylate producing methyl 3- (2-oxo-oxazolidin-3-yl) propanoate, which reacted with n-butylamine and 1,6-hexanediamine to give mono and bis cyclic carbamate derivatives. The attack of amine to carbonyl of heterocyclic ring of carbamate produced the hydroxylethyl substituted urea, while the attack to carbon-oxygen bond generated carbamic acid, which further underwent dehydration forming cyclic urea and/or de-carbon dioxide forming polyamine. The products were characterized by NMR and FT-IR. The reaction mechanism is finally proposed.%以乙醇胺和碳酸二甲酯为原料,在醋酸锌的催化下合成环状氨基甲酸酯,与丙烯酸甲酯反应制备3-(2-噁唑烷酮)丙酸甲酯,在K2CO3催化下进一步与正丁胺、1,6-己二胺发生酰胺化反应,得到了单、双环状氨基甲酸酯衍生物.有机胺与环状氨基甲酸酯的羰基反应形成羟乙基取代脲,与烷氧基反应形成开环的胺基甲酸,该化合物进一步脱水形成环状脲,脱二氧化碳形成多胺化合物.用NMR和红外谱图对开环产物进行表征,并初步探讨了其反应历程.

  18. Preparation of Zeolite X Membranes on Porous Ceramic Substrates with Zeolite Seeds

    Institute of Scientific and Technical Information of China (English)

    Zhongqiang Xu; Qingling Chen; Guanzhong Lu

    2002-01-01

    Zeolite X membranes were investigated by in-situ hydrothermal synthesis on porous ceramic tubes precoated with zeolite X seeds or precursor amorphous aluminosilicate, and porous α-Al2O3 ceramic tubes with a pore size of 50 200 nm were employed as supports. Zeolite X crystals were synthesized by the classic method and mixed into deionized water as a slurry with a concentration of 0.2 0.5wt%, having a range of crystal sizes from 0.2 to 2μm. Crystal seeds were pressed into the pores near the inner surface of the ceramic tubes, and crystallization took place at 95℃ for 24-96 h. It was also investigated that Boehmite sol added with zeolite X seeds was precoated on ceramic supports to form a layer of γ-Al2O3 by heating, and hydrothermal crystallization could then take place to prepare the zeolite membranes on the composite ceramic tubes. The crystal species were characterized by XRD, and the morphology of the supports subjected to crystallization was characterized by SEM. The composite zeolite membranes have zeolitic top-layers with a thickness of 10-25 μm, and zeolite crystals can be intruded into pores of the supports as deeply as 100μm. The experimental results indicate that the precoating of zeolitic seeds on supports is beneficial to crystallization by shortening the synthesis time and improving the membrane strength. The resulting zeolite X membrane shows permselectivity to tri-n-butylamine((C4H9)3N) over perfluro-tributyl-amine ((C4Fg)3N), and a permeance ratio of 57 for ((C4Hg)3N to (C4F9)3N could be reached at 350℃. Permeances of BZ, EB and TIPB through the zeolite membrane were also measured and were found to slightly increase with temperature.

  19. 丁胺卡那霉素鞘内注射治疗颅内感染15例分析

    Institute of Scientific and Technical Information of China (English)

    王学忠; 冯雨果; 冯圣勇; 周林; 范永智; 冯静

    2014-01-01

    Objective To explore the use of agmatine Cara kanamycin treatment method and clinical effect of intrathecal intracranial infection, 15 cases of intracranial infection were treated with amikacin, Cara amphotericin 80.0mg, each diluted with normal saline to 5ml, after lumbar puncture intrathecal injection, 1 times / day, and white blood cels in cerebrospinal fluid in patients with normal body temperature and. Results 10 cases were cured, 4 cases improved, 1 cases died, the mortality rate of 6%, prognostic and good rate was 94%, conclusion: butylamine Cara mycomycin intrathecal injection for the treatment of intracranial infection can achieve satisfactory effect.%目的:探讨鞘内使用丁胺卡那霉素治疗颅内感染的方法及临床疗效,对15例颅内感染患者采用丁胺卡那霉素80.0mg,每次用生理盐水稀释至5ml,经腰椎穿刺鞘内注射,1次/天,至患者体温及脑脊液中白细胞恢复正常。结果治愈10例,好转4例,死亡1例,病死率6.0%,预后良好率达94%,结论丁胺卡那霉素鞘内注射治疗颅内感染能取得满意疗效。

  20. Synthesis and profiling of [3H]trantinterol excretion following oral administration of rats

    Institute of Scientific and Technical Information of China (English)

    ZHANG Tian-hong; ZHANG Cheng; YANG Cui-ping; WANG Xiao-ying; LIAO Sha; SUN Mu-zhen; LI Jing-lai; ZHANG Zhen-qing

    2015-01-01

    OBJECTIVE To synthesize[3H]labelled trantinterol and determine the mass balance in rats and the profile of trantinterol and its metabolites in excreta. METHODS [3H]Trantinterol was synthesised from the intermediate1-(4-amino-3-chloro-5-trifluoromethyl-phenyl)-2-bromo-ethanone through reduction by sodium borotritide and aminolysis by t-butylamine. Following an oral dose of[3H] trantinterol(45.5 MBq·kg-1)to bile duct cannulated(BDC)rats and normal rats. Bile,urine and faeces were collected individually before and after dosing at different times. Liquid scintillation counter(LSC) was used to detect total radioactivity recovery and HPLC/radio-detector for metabolite profiling in urine and bile. RESULTS The majority(73.6%)of the administered radioactivity was recovered in the first 24 h postdose with 48.3%in urine and 25.4%in faeces. It was cumulated to(84.7±6.8)%till 168 h. In BDC rats,29.3%of the dose was recovered in the bile 3 d post-dose. According to the peak area ratio determined by HPLC/radio-detector,only 4.7%and 9.5%of the radioactive dose were excreted as the parent drug in urine and bile,respectively,while the majority of the remaining radioactivity was excreted in the form of various metabolites. CONCLUSION Following oral administration in rats,trantinterol is completely absorbed,extensively metabolized and rapidly excreted mainly in urine as various metabolites.

  1. Occurrence and profiling of multiple nitrosamines in source water and drinking water of China.

    Science.gov (United States)

    Wang, Wanfeng; Yu, Jianwei; An, Wei; Yang, Min

    2016-05-01

    The occurrence of multiple nitrosamines was investigated in 54 drinking water treatment plants (DWTPs) from 30 cities across major watersheds of China, and the formation potential (FP) and cancer risk of the dominant nitrosamines were studied for profiling purposes. The results showed that N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA) and N-nitrosodi-n-butylamine (NDBA) were the most abundant in DWTPs, and the concentrations in source water and finished water samples were not detected (ND) -53.6ng/L (NDMA), ND -68.5ng/L (NDEA), ND -48.2ng/L (NDBA). The frequencies of detection in source waters were 64.8%, 61.1% and 51.8%, and 57.4%, 53.7%, and 37% for finished waters, respectively. Further study indicated that the FPs of the three main nitrosamines during chloramination were higher than those during chlorination and in drinking water. The results of Principal Components Analysis (PCA) showed that ammonia was the most closely associated factor in nitrosamine formation in the investigated source water; however, there was no significant correlation between nitrosamine-FPs and the values of dominant water-quality parameters. The advanced treatment units (i.e., ozonation and biological activated carbon) used in DWTPs were able to control the nitrosamine-FPs effectively after disinfection. The target pollutants posed median and maximum cancer risks of 2.99×10(-5) and 35.5×10(-5) to the local populations due to their occurrence in drinking water.

  2. Assessing the Origins of Aliphatic Amines in the Murchison Meteorite from their Compound-Specific Carbon Isotopic Ratios and Enantiomeric Composition

    Science.gov (United States)

    Aponte, Jose; Dworkin, Jason; Elsila, Jamie E.

    2014-01-01

    The study of meteoritic organic compounds provides a unique window into the chemical inventory of the early Solar System and prebiotic chemistry that may have been important for the origin of life on Earth. Multiple families of organic compounds have been extracted from the Murchison meteorite, which is one of the most thoroughly studied carbonaceous chondrites. The amino acids extracted from Murchison have been extensively analyzed, including measurements of non-terrestrial stable isotopic ratios and discoveries of L-enantiomeric excesses for alpha-dialkyl amino acids, notably isovaline. However, although the isotopic signatures of bulk amine-containing fractions have been measured, the isotopic ratios and enantiomeric composition of individual aliphatic amines, compounds that are chemically related to amino acids, remain unknown. Here, we report a novel method for the extraction, separation, identification and quantitation of aliphatic monoamines extracted from the Murchison meteorite. Our results show a complete suite of structural isomers, with a larger concentration of methylamine and ethylamine and decreasing amine concentrations with increasing carbon number. The carbon isotopic compositions of fourteen meteoritic aliphatic monoamines were measured, with delta C-13 values ranging from +21% to +129%, showing a decrease in C-13 with increasing carbon number, a relationship that may be consistent with the chain elongation mechanism under kinetic control previously proposed for meteoritic amino acids. We also found the enantiomeric composition of sec-butylamine, a structural analog to isovaline, was racemic within error, while the isovaline extracted from the same Murchison piece showed an L-enantiomeric excess of 9.7; this result suggested that processes leading to enantiomeric excess in the amino acid did not affect the amine. We used these collective data to assess the primordial synthetic origins of these meteoritic aliphatic amines and their potential

  3. Ambient temperature nanoelectrospray ion mobility detector for high performance liquid chromatography in determining amines.

    Science.gov (United States)

    Chen, Chuang; Hou, Keyong; Wang, Weiguo; Li, Jinghua; Li, Haiyang

    2014-09-01

    A nanoelectrospray ionization ion mobility spectrometer (nanoESI-IMS) working at ambient pressure and ambient temperature was developed as a detector of high performance liquid chromatography (HPLC) to achieve sensitive detection of amines with no derivatization and meanwhile provide another dimension of separation. The easier desolvation property of the charged droplets formed in nanoESI source enabled complete desolvation of the product ions of sixteen amines and drugs using the nanoESI-IMS at ambient temperature. Working at ambient temperature was good for suppressing the dissociation of thermal volatile ions, such as only the proton adducted molecular ions were observed for morphine in the nanoESI-IMS. Besides, the resolving power of the nanoESI-IMS also showed an increasing tendency as lowering the working temperature, an increment of 19 percent and 10 percent was observed for diethylamine and triethylamine as the temperature dropped from 92°C to 32°C. The resolving power of the nanoESI-IMS at 32°C for the 16 tested compounds was amid 33-44. With the nanoESI-IMS coupled to HPLC, a six-compound mixture including isomers was successfully separated and detected without any derivatization. And linear response ranges of 1 to 20, 0.5 to 20, and 0.8 to 20μgml(-1) and limits of detection of 0.25, 0.15, and 0.17μgml(-1) for triethylamine, diethylamine, and butylamine, respectively, were obtained with the hyphenated system. These results showed the excellent performance of the two-dimensional separation and detection method in direct qualitative and quantitative analyses of amines.

  4. H3PW12O40 Encapsulation by Nanoporous Metal Organic Framework HKUST-1: Synthesis, Characterization, Activity and Stability.

    Science.gov (United States)

    Rafiee, Ezzat; Nobakht, Narges

    2016-01-01

    Hybrid composite material was obtained through encapsulation of H3PW12O40 (PW) into HKUST-1 (Cu3(BTC)2, BTC = 1,3,5-benzenetricarboxylic acid), in molar composition of 5 Cu(NO3)2 · 3H2O/2.8 BTC/0.3 PW/0.6 CTAB by adding solutions of PW and copper salts to mixture of BTC and surfactant. The catalyst was characterized by various techniques including powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), laser particle size analyzer, Brunauer Emmett-Teller (BET). The acidity of the catalyst was measured by a potentiometric titration with n-butylamine and PW/HKUST-1 presented very strong acidic sites with Ei > 100 mV. This nano catalyst was successfully used for the synthesis of various β-keto enol ethers at 45 °C with 51-98% yield after 5-75 min. The catalyst was easily recycled and reused at least four times without significant loss of its activity (94% yield after forth run). The presence of the PW in PW/HKUST-1 and reused PW/HKUST-1 structure, eliminating any doubt about collapse of the HKUST-1 after catalytic reaction and can be followed by FT-IR, XRD and SEM techniques. Brönsted and Lewis acidity of the PW/HKUST-1 catalyst was distinguished by studying the FT-IR and determined by chemisorption of pyridine. The strength and dispersion of the protons on PW/HKUST-1 was considerably high and active surface protons became more available for reactant.

  5. Photophysical properties of 1,8-naphthalic anhydride in aprotic solvents: An electron acceptor in excited state

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Sujay; Biswas, Subhanip; Mondal, Mousumi; Basu, Samita, E-mail: samita.basu@saha.ac.in

    2014-01-15

    1,8-Naphthalic anhydride (NAN) has long been known as an intermediate for the synthesis of 1,8-naphthalimide derivatives with diverse applications. Uses of NAN for other purposes are restricted because it hydrolyzes in water and other protic solvents. In the current work we have investigated the absorption, steady-state and time-resolved fluorescence spectroscopy of NAN in eight different aprotic solvents of varying polarity. The compound is found to have different quantum yields in all the solvents. Astoundingly, NAN shows minimal fluorescence yield in dimethyl sulphoxide and N,N-dimethylformamide which is found to originate from pure collisional quenching owing to proton affinity of the solvent. In aprotic solvents acetonitrile and ethyl acetate, fluorescence emission and lifetime of NAN are quenched on addition of aliphatic amines namely triethylamine (TEA), tri-N-butylamine (TBA) and diisopropylethylamine (DIEA). Laser flash photolysis experiments in acetonitrile solvent have been used to find out the transient intermediates, which depict the involvement of photo-induced electron transfer from the amines to NAN. Hence, NAN has the potential to act as an efficient photo-induced electron acceptor in aprotic medium. -- Highlights: • In aprotic solvents NAN absorbs with maximum around 330–340 nm. • NAN fluoresce in aprotic solvents with maximum around 345–395 nm. • NAN has negligibly poor fluorescence in DMSO and DMF. • Fluorescence of NAN in aprotic solvents is quenched by TEA, TBA and DIEA. • Photo-induced electron transfer from the amines to NAN is the reason for such interaction.

  6. Crystal engineered acid–base complexes with 2D and 3D hydrogen bonding systems using p-hydroxybenzoic acid as the building block

    Directory of Open Access Journals (Sweden)

    PU SU ZHAO

    2010-04-01

    Full Text Available p-Hydroxybenzoic acid (p-HOBA was selected as the building block for self-assembly with five bases, i.e., diethylamine, tert-butylamine, cyclohexylamine, imidazole and piperazine, and generation of the corresponding acid–base complexes 1–5. Crystal structure analyses suggest that proton-transfer from the carboxyl hydrogen to the nitrogen atom of the bases can be observed in 1–4, while only in 5 does a solvent water molecule co-exist with p--HOBA and piperazine. With the presence of O–H···O hydrogen bonds in 1–4, the deprotonated p-hydroxybenzoate anions (p-HOBAA– are simply connected each other in a head-to-tail motif to form one-dimensional (1D arrays, which are further extended to distinct two-dimensional (2D (for 1 and 4 and three-dimensional (3D (for 2 and 3 networks via N–H···O interactions. While in 5, neutral acid and base are combined pair-wise by O–H···N and N–H···O bonds to form a 1D tape and then the 1D tapes are sequentially combined by water molecules to create a 3D network. Some interlayer or intralayer C–H···O, C–H···p and p×××p interactions help to stabilize the supramolecular buildings. Melting point determination analyses indicate that the five acid–base complexes are not the ordinary superposition of the reactants and they are more stable than the original reactants.

  7. 曲克芦丁钯配合物的制备及其对Heck反应的催化性能%Synthesis of troxerutin-Pd complex and its catalytic properties for Heck reaction

    Institute of Scientific and Technical Information of China (English)

    徐启杰; 时文中; 刘雷英; 王文豪; 崔元臣

    2011-01-01

    The complex of troxerutin-Pd was synthesized. The structure of the complex was characterized by means of infrared spectrometry and ultraviolet spectrometry. Besides, the catalytic performance of the complex for the Heck arylation reaction of bromobenzene and acrylic acid was examined. Results showed that the complex had good catalytic performance for the Heck arylation reaction of bromobenzene and acrylic acid under optimized reaction conditions.Namely, a yield of above 70% was reached at bromobenzene to acrylic acid molar ratio of 1∶ 2,reaction time of 8 h, and reaction temperature of 120 ℃ in the presence of tri-n-butylamine as the alkali and tetrabutylammonium bromide as the solvent.%制备了曲克芦丁钯配合物,利用红外光谱和紫外光谱表征了配合物的结构;同时考察了其对溴苯和丙烯酸的Heck芳基化反应的催化性能.结果表明:在反应物的物质的量之比(溴苯与丙烯酸)为1:2、反应温度120℃、反应时间8 h、三正丁胺为碱、四丁基溴化铵为溶剂的条件下,曲克芦丁钯配合物对溴苯和丙烯酸的Heck芳基化反应有较好的催化作用,产率可达70%以上.

  8. Effect of foamability index of short chain alkyl amines on flotation of quartz

    Directory of Open Access Journals (Sweden)

    Szczerkowska Sabina

    2016-01-01

    Full Text Available Amines can be used for flotation of various minerals, especially quartz. The flotation efficiency of quartz depends on the amine type and dose. It was proved that the shorter alkyl amine, higher amine concentration has to be used to recover quartz at the same level. In flotation amines play a role of both collectors and frothers. The ability of a amine to collect particles can be expressed in the form of contact angle, while the foaming properties by different parameters including dynamic foamability index (DFI and critical coalescence concentration (CCC. Determination of DFI and CCC requires advanced techniques and methods. Therefore, in this paper a rapid and facile method for determination of foaming properties of amines and also other surfactants was used. It was based on measuring the initial foam and froth heights in a conventional flotation machine at different concentrations of surfactants. The foam height-concentration curve was described by utilizing an empirical equation which was based on one-adjustable parameter called the foamability index (FI. In this work the foamability index was determined for butylamine (ButNH2, hexylamine (HexNH2 and octylamine (OctNH2 as examples of short chain alkyl amines. The determined foamability indices were 92, 12 and 4 mg/dm3 for ButNH2, HexNH2 and OctNH2, respectively. It was shown that when the flotation results of quartz were presented in the form of recovery versus normalized amine concentration in relation to the foamability index (c/FI, all the experimental data points converged to one curve. It indicates that amines act similarly but at different concentrations expressed as FI. The foamability index seems to be a useful parameter for characterizing any flotation frother.

  9. Pulse radiolysis of solutions of stilbene. 2. Ionic and free radical species in benzene and cyclohexane

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, E.A.; Salmon, G.A.

    1978-02-23

    The spectra of the radical cation and anion of trans-stilbene in benzene and cyclohexane have been resolved using various electron and positive charge scavengers. The decay of the ions is second order in both solvents. In cyclohexane only part of the yield of solvent cations is scavengeable by trans-stilbene; in benzene the stilbene cation is converted to the dimer in the presence of high stilbene concentrations. The electron scavengers N/sub 2/O and c-C/sub 6/F/sub 12/ compete directly with trans-stilbene for electrons and we deduce rate constants for the reactions of electrons with c-C/sub 6/F/sub 12/ and trans-stilbene of (1.2 +- 0.6) x 10/sup 12/ and (0.72 +- 0.5) x 10/sup 12/ M/sup -1/ s/sup -1/, respectively. SF/sub 6/ reduces the yield of trans-stilbene anion more efficiently than can be attributed solely to electron scavenging and it is shown that electron transfer from trans-stilbene anion to SF/sub 6/ occurs at a rate constant, k/sub 4/ = (3.9 +- 0.4) x 10/sup 9/ M/sup -1/ s/sup -1/. The presence of either aniline or n-butylamine causes enhancement of the yield of stilbene anion, the effect being particularly marked in the case of aniline. Possible explanations of the effect are considered. It is proposed that the UV absorptions are due to radical species, which in cyclohexane solution are most probably formed by the addition of cyclohexyl radicals to the olefinic double bond of the stilbenes.

  10. Nonadiabatic dynamics of photoinduced proton-coupled electron transfer in a solvated phenol-amine complex.

    Science.gov (United States)

    Goyal, Puja; Schwerdtfeger, Christine A; Soudackov, Alexander V; Hammes-Schiffer, Sharon

    2015-02-12

    Photoinduced concerted electron-proton transfer (EPT), denoted photo-EPT, is important for a wide range of energy conversion processes. Transient absorption and Raman spectroscopy experiments on the hydrogen-bonded p-nitrophenylphenol-t-butylamine complex, solvated in 1,2-dichloroethane, suggested that this complex may undergo photo-EPT. The experiments probed two excited electronic states that were interpreted as an intramolecular charge transfer (ICT) state and an EPT state. Herein mixed quantum mechanical/molecular mechanical nonadiabatic surface hopping dynamics is used to investigate the relaxation pathways following photoexcitation. The potential energy surface is generated on the fly with a semiempirical floating occupation molecular orbital complete active space configuration interaction method for the solute molecule and a molecular mechanical force field for the explicit solvent molecules. The free energy curves along the proton transfer coordinate illustrate that proton transfer is thermodynamically and kinetically favorable on the lower-energy excited state but not on the higher-energy excited state, supporting the characterization of these states as EPT and ICT, respectively. The nonadiabatic dynamics simulations indicate that the population decays from the ICT state to the EPT state in ∼100 fs and from the EPT state to the ground state on the slower time scale of ∼1 ps, qualitatively consistent with the experimental measurements. For ∼54% of the trajectories, the proton transfers from the phenol to the amine in ∼400 fs on the EPT state and then transfers back to the phenol rapidly upon decay to the ground state. Thus, these calculations augment the original interpretation of the experimental data by providing evidence of proton transfer on the EPT state prior to decay to the ground state. The fundamental insights obtained from these simulations are also relevant to other photo-EPT processes.

  11. Determination of eight nitrosamines in water at the ng L(-1) levels by liquid chromatography coupled to atmospheric pressure chemical ionization tandem mass spectrometry.

    Science.gov (United States)

    Ripollés, Cristina; Pitarch, Elena; Sancho, Juan V; López, Francisco J; Hernández, Félix

    2011-09-19

    In this work, we have developed a sensitive method for detection and quantification of eight N-nitrosamines, N-nitrosodimethylamine (NDMA), N-nitrosomorpholine (NMor), N-nitrosomethylethylamine (NMEA), N-nitrosopirrolidine (NPyr), N-nitrosodiethylamine (NDEA), N-nitrosopiperidine (NPip), N-nitroso-n-dipropylamine (NDPA) and N-nitrosodi-n-butylamine (NDBA) in drinking water. The method is based on liquid chromatography coupled to tandem mass spectrometry, using atmospheric pressure chemical ionization (APCI) in positive mode with a triple quadrupole analyzer (QqQ). The simultaneous acquisition of two MS/MS transitions in selected reaction monitoring mode (SRM) for each compound, together with the evaluation of their relative intensity, allowed the simultaneous quantification and reliable identification in water at ppt levels. Empirical formula of the product ions selected was confirmed by UHPLC-(Q)TOF MS accurate mass measurements from reference standards. Prior to LC-MS/MS QqQ analysis, a preconcentration step by off-line SPE using coconut charcoal EPA 521 cartridges (by passing 500 mL of water sample) was necessary to improve the sensitivity and to meet regulation requirements. For accurate quantification, two isotope labelled nitrosamines (NDMA-d(6) and NDPA-d(14)) were added as surrogate internal standards to the samples. The optimized method was validated at two concentration levels (10 and 100 ng L(-1)) in drinking water samples, obtaining satisfactory recoveries (between 90 and 120%) and precision (RSDwater samples: chlorinated from drinking water and wastewater treatment plants (DWTP and WWTP, respectively), wastewaters subjected to ozonation and tap waters.

  12. Nanoassembled thin film gas sensors. III. Sensitive detection of amine odors using TiO2/poly(acrylic acid) ultrathin film quartz crystal microbalance sensors.

    Science.gov (United States)

    Lee, Seung-Woo; Takahara, Naoki; Korposh, Sergiy; Yang, Do-Hyeon; Toko, Kiyoshi; Kunitake, Toyoki

    2010-03-15

    Quartz crystal microbalance (QCM) gas sensors based on the alternate adsorption of TiO(2) and polyacrilic acid (PAA) were developed for the sensitive detection of amine odors. Individual TiO(2) gel layers could be regularly assembled with a thickness of approximately 0.3 nm by the gas-phase surface sol-gel process (GSSG). The thickness of the poly(acrylic acid) (PAA) layer is dependent on its molecular weight, showing different thicknesses of approximately 0.4 nm for PAA(25) (Mw 250,000) and 0.6-0.8 nm for PAA(400) (Mw 4,000,000). The QCM sensors showed a linear response to ammonia in the concentration range 0.3-15 ppm, depending on the deposition cycle of the alternate TiO(2)/PAA layer. The ammonia binding is based on the acid-base interaction to the free carboxylic acid groups of PAA and the limit of detection (LOD) of the 20-cycle TiO(2)/PAA(400) film was estimated to be 0.1 ppm when exposed to ammonia. The sensor response was very fast and stable in a wide relative humidity (rH) range of 30-70%, showing almost the same frequency changes at a given concentration of ammonia. Sensitivity to n-butylamine and ammonia was higher than to pyridine, which is owing to the difference of molecular weight and basicity of the amine analytes. The alternate TiO(2)/PAA(400) films have a highly effective ability to capture amine odors, and the ambient ammonia concentration of 15 ppm could be condensed up to approximately 20,000 ppm inside the films.

  13. Synthesis and physico-chemical characterization of CeO{sub 2}/ZrO{sub 2}-SO{sub 4}{sup 2-} mixed oxides

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez E, J. M.; Silva R, R.; Garcia A, R. [Instituto Tecnologico de Ciudad Madero, Div. de Estudios de Posgrado e Investigacion, Juventino Rosas y Jesus Urueta s/n, Col. Los Mangos, 89440 Ciudad Madero, Tamaulipas (Mexico); Garcia S, L. A. [IPN, Centro Interdisciplinario de Investigaciones y de Estudios sobre Medio Ambiente y Desarrollo, 30 de Junio No. 1520, Barrio La Laguna Ticoman, 07340 Mexico D. F. (Mexico); Handy, B. E.; Cardenas G, G. [Universidad Autonoma de San Luis Potosi, CIEP, Facultad de Ciencias Quimicas, Av. Dr. Manuel Nava No. 6, Zona Universitaria, 78210 SLP, San Luis Potosi (Mexico); Cueto H, A. [Universidad Autonoma Metropolitana, Unidad Azcapotzalco, Av. San Pablo No. 180, Col. Reynosa Tamaulipas, 02200 Mexico D. F. (Mexico)

    2012-07-01

    Environmentally friendly solid-acid catalysts CeO{sub 2}/ZrO{sub 2}-SO{sub 4}{sup 2-} were prepared by the sol gel method varying CeO{sub 2} content (10, 20 and 30 wt %) and using sulfation in situ, maintaining the sulfate ions amount present in the materials at 20 wt %. ZrO{sub 2} and ZrO{sub 2}-SO{sub 4}{sup 2-} were also prepared for comparison proposes using the same synthesis method. The materials were characterized by X-ray diffraction, nitrogen physisorption, potentiometric titration with n-butylamine, decomposition of 2-propanol and n-pentane isomerization. The specific surface area of ZrO{sub 2}-SO{sub 4}{sup 2-} was high (160 m{sup 2}/g) compared with the unmodified ZrO{sub 2} (80 m{sup 2}/g), however this area decreased with increasing the CeO{sub 2} content (37-100 m{sup 2}/g). There was no significant effect of CeO{sub 2} on the tetragonal structure of ZrO{sub 2}-SO{sub 4}{sup 2-}. The variation of acid sites amount runs parallel to the change of specific surface area. The acid sites amount decreased with increasing cerium oxide content. The decomposition of 2-propanol results fundamentally in the formation of dehydration products such as propylene and diisopropyl ether, both involving acid sites. In addition, a good performance during the n-pentane isomerization was observed for these materials. The selectivity towards isopentane reaches 84% when the Pt/CeO{sub 2}/ZrO{sub 2}-SO{sub 4}{sup 2-} catalyst with the highest CeO{sub 2} content was used. (Author)

  14. Studies on Pyridine Derivatives (Ⅺ):Synthesis and Herbicidal Activities of Both Enantiomers of 2-sec-Butylamino-5-(2-chloropyrid-4-yl)-1,3,4-thiodiazoles%吡啶衍生物研究(Ⅺ):2-仲丁胺基-5-(2-氯吡啶-4-基)-1,3,4-噻二唑对映异构体的合成及除草活性

    Institute of Scientific and Technical Information of China (English)

    冉兆晋; 车超; 李楠; 肖玉梅; 覃兆海

    2007-01-01

    Both enantiomers of 2-sec-butylamino-5-(2-chloropyrid-4-yl)-1,3,4-thiodiazoles (BCPT),a powerful racemic herbicidal compound which was found in previous research,were synthesized from R-and S-butylamine respectively. The preliminary bioassay results showed that three of the thiodiazoles (racemate and enantiomers) were excellent growth inhibitors to both roots and stems of barnyard grass.The S-( + ) enantiomer was the strongest for stem growth inhibition,and R-(-) enantiomer was the weakest. But they had little inhibiting difference on root growth.%2-仲丁胺基-5-(2-氯吡啶-4-基)-1,3,4-噻二唑(BCPT)是早期发现的一个具有良好除草活性的外消旋先导化合物,报道了使用R/S-仲丁胺为原料分别合成BCPT的两个对映异构体的方法.初步生测结果显示,3种噻二唑化合物(外消旋体和两个对映异构体)对稗草的根和茎均表现出较强的抑制作用,其中S-(+)对映异构体对茎的抑制作用强于R-(-)对映异构体和外消旋体,但对根的生长抑制作用三者间没有显著差异.

  15. N-nitrosamine formation by monochloramine, free chlorine, and peracetic acid disinfection with presence of amine precursors in drinking water system.

    Science.gov (United States)

    West, Danielle M; Wu, Qihua; Donovan, Ariel; Shi, Honglan; Ma, Yinfa; Jiang, Hua; Wang, Jianmin

    2016-06-01

    In this study, the formation of eight N-nitrosamines, N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine, N-nitrosomethylamine, N-nitrosodi-n-propylamine, N-nitrosodi-n-butylamine, N-Nitrosopiperidine, N-Nitrosopyrrolidine, N-Nitrosomorpholine, were systematically evaluated with respect to seven N-nitrosamine precursors (dimethylamine, trimethylamine, 3-(dimethylaminomethyl)indole, 4-dimethylaminoantipyrine, ethylmethylamine, diethylamine, dipropylamine) and three disinfectants (monochloramine, free chlorine, peracetic acid) under variable dosages, exposure times, and pH in a drinking water system. Without the presence of the seven selected N-nitrosamine precursors N-nitrosamine formation was not observed under any tested condition except very low levels of N-Nitrosopyrrolidine under some conditions. With selected N-nitrosamine precursors present N-nitrosamines formed at different levels under different conditions. The highest N-nitrosamine formation was NDMA with a maximum concentration of 1180 ng/L by monochloramine disinfection with precursors present; much lower levels of N-nitrosamines were formed by free chlorine disinfection; and no detectable level of N-nitrosamines were observed by peracetic acid disinfection except low level of N-Nitrosodi-n-propylamine under some conditions. NDMA formation was not affected by pH while four other N-nitrosamine formations were slightly affected by sample pH tested between 7 and 9, with formation decreasing with increasing pH. Monochloramine exposure time study displayed fast formation of N-nitrosamines, largely formed in four hours of exposure and maximized after seven days. This was a systematic study on the N-nitrosamine formation with the seven major N-nitrosamine precursors presence and absence under different conditions, including peracetic acid disinfection which has not been studied elsewhere.

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

    Institute of Scientific and Technical Information of China (English)

    帅长庚; 邓淑珍; 宋玉苏; 银继伟

    2001-01-01

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

  17. Palladium nanoparticles decorated on reduced graphene oxide rotating disk electrodes toward ultrasensitive hydrazine detection: effects of particle size and hydrodynamic diffusion.

    Science.gov (United States)

    Krittayavathananon, Atiweena; Srimuk, Pattarachai; Luanwuthi, Santamon; Sawangphruk, Montree

    2014-12-16

    Although metal nanoparticle/graphene composites have been widely used as the electrode in electrochemical sensors, two effects, consisting of the particle size of the nanoparticles and the hydrodynamic diffusion of analytes to the electrodes, are not yet fully understood. In this work, palladium nanoparticles/reduced graphene oxide (PdNPs/rGO) composites were synthesized using an in situ polyol method. Palladium(II) ions and graphene oxide were reduced together with a reducing agent, ethylene glycol. By varying the concentration of palladium(II) nitrate, PdNPs with different sizes were decorated on the surface of rGO sheets. The as-fabricated PdNPs/rGO rotating disk electrodes (RDEs) were investigated toward hydrazine detection. Overall, a 3.7 ± 1.4 nm diameter PdNPs/rGO RDE exhibits high performance with a rather low limit of detection of about 7 nM at a rotation speed of 6000 rpm and provides a wide linear range of 0.1-1000 μM with R(2) = 0.995 at 2000 rpm. This electrode is highly selective to hydrazine without interference from uric acid, glucose, ammonia, caffeine, methylamine, ethylenediamine, hydroxylamine, n-butylamine, adenosine, cytosine, guanine, thymine, and l-arginine. The PdNPs/rGO RDEs with larger sizes show lower detection performance. Interestingly, the detection performance of the electrodes is sensitive to the hydrodynamic diffusion of hydrazine. The as-fabricated electrode can detect trace hydrazine in wastewater with high stability, demonstrating its practical use as an electrochemical sensor. These findings may lead to an awareness of the effect of the hydrodynamic diffusion of analyte that has been previously ignored, and the 3.7 ± 1.4 nm PdNPs/rGO RDE may be useful toward trace hydrazine detection, especially in wastewater from related chemical industries.

  18. Size-separated sampling and analysis of isocyanates in workplace aerosols. Part I. Denuder--cascade impactor sampler.

    Science.gov (United States)

    Dahlin, Jakob; Spanne, Mårten; Karlsson, Daniel; Dalene, Marianne; Skarping, Gunnar

    2008-07-01

    Isocyanates in the workplace atmosphere are typically present both in gas and particle phase. The health effects of exposure to isocyanates in gas phase and different particle size fractions are likely to be different due to their ability to reach different parts in the respiratory system. To reveal more details regarding the exposure to isocyanate aerosols, a denuder-impactor (DI) sampler for airborne isocyanates was designed. The sampler consists of a channel-plate denuder for collection of gaseous isocyanates, in series with three-cascade impactor stages with cut-off diameters (d(50)) of 2.5, 1.0 and 0.5 mum. An end filter was connected in series after the impactor for collection of particles smaller than 0.5 mum. The denuder, impactor plates and the end filter were impregnated with a mixture of di-n-butylamine (DBA) and acetic acid for derivatization of the isocyanates. During sampling, the reagent on the impactor plates and the end filter is continuously refreshed, due to the DBA release from the impregnated denuder plates. This secures efficient derivatization of all isocyanate particles. The airflow through the sampler was 5 l min(-1). After sampling, the samples containing the different size fractions were analyzed using liquid chromatography-mass spectrometry (LC-MS)/MS. The DBA impregnation was stable in the sampler for at least 1 week. After sampling, the DBA derivatives were stable for at least 3 weeks. Air sampling was performed in a test chamber (300 l). Isocyanate aerosols studied were thermal degradation products of different polyurethane polymers, spraying of isocyanate coating compounds and pure gas-phase isocyanates. Sampling with impinger flasks, containing DBA in toluene, with a glass fiber filter in series was used as a reference method. The DI sampler showed good compliance with the reference method, regarding total air levels. For the different aerosols studied, vast differences were revealed in the distribution of isocyanate in gas and

  19. Synthesis of Particle-Free Silver Conductive Ink and Investigation of Fabrication of Conductive Film by Printing%无颗粒型银导电墨水的制备及其印刷成膜研究

    Institute of Scientific and Technical Information of China (English)

    聂晓蕾; 王虹; 邹竞

    2012-01-01

    Particle-free conductive ink was prepared, taking stiver citrate as conductive metal precursor, sec-butylamine as com-plexing agent and ethanol as media adjusting the viscosity and wettability. The ink could be printed on PET substrate by gravure printing, and silver conductive film with high electrical conductivity was obtained after thermal treated at low temperature. Silver citrate, silver citrate based conductive ink and silver conductive film were characterized with EDS, STA, IR, XRD, SEM and four point probe method. The results of STA showed that the mass of the conductive ink came to constant at 132 ℃ which is much lower than that of silver citrate (210 ℃); the results of SEM and XRD showed that the silver conductive film cured at 150 ℃ was constituted by compact silver nano particles with high purity; the result of four point probe method showed that its sheet resistance was 1. 83 Ω - □‐1.%以柠檬酸银为导电金属前驱体化合物,仲丁胺为络合剂,并添加乙醇调节粘度和表面张力等物性参数,制备了无颗粒型银导电墨水.该导电墨水可以采用凹版印刷方式印刷在PET片基上,并且在较低的热处理温度下即可获得导电性较好的银导电膜.利用X射线光电子能谱仪、同步热分析仪、红外光谱仪、X射线衍射仪、扫描电子显微镜和四探针测试仪对柠檬酸银、导电墨水以及银导电膜进行表征.结果表明导电墨水在132℃时残留质量即达到恒重,远低于柠檬酸银的210℃;经150℃热处理之后,银导电膜由均匀致密、纯度高的纳米银颗粒组成;经150℃热处理50 min后得到的银导电膜的方块电阻值为1.83 Ω·口-1.

  20. Chemical reactivity and skin sensitization potential for benzaldehydes: can Schiff base formation explain everything?

    Science.gov (United States)

    Natsch, Andreas; Gfeller, Hans; Haupt, Tina; Brunner, Gerhard

    2012-10-15

    Skin sensitizers chemically modify skin proteins rendering them immunogenic. Sensitizing chemicals have been divided into applicability domains according to their suspected reaction mechanism. The widely accepted Schiff base applicability domain covers aldehydes and ketones, and detailed structure-activity-modeling for this chemical group was presented. While Schiff base formation is the obvious reaction pathway for these chemicals, the in silico work was followed up by limited experimental work. It remains unclear whether hydrolytically labile Schiff bases can form sufficiently stable epitopes to trigger an immune response in the living organism with an excess of water being present. Here, we performed experimental studies on benzaldehydes of highly differing skin sensitization potential. Schiff base formation toward butylamine was evaluated in acetonitrile, and a detailed SAR study is presented. o-Hydroxybenzaldehydes such as salicylaldehyde and the oakmoss allergens atranol and chloratranol have a high propensity to form Schiff bases. The reactivity is highly reduced in p-hydroxy benzaldehydes such as the nonsensitizing vanillin with an intermediate reactivity for p-alkyl and p-methoxy-benzaldehydes. The work was followed up under more physiological conditions in the peptide reactivity assay with a lysine-containing heptapeptide. Under these conditions, Schiff base formation was only observable for the strong sensitizers atranol and chloratranol and for salicylaldehyde. Trapping experiments with NaBH₃CN showed that Schiff base formation occurred under these conditions also for some less sensitizing aldehydes, but the reaction is not favored in the absence of in situ reduction. Surprisingly, the Schiff bases of some weaker sensitizers apparently may react further to form stable peptide adducts. These were identified as the amides between the lysine residues and the corresponding acids. Adduct formation was paralleled by oxidative deamination of the parent

  1. Electron Injection Enhancement by Diamond-Like Carbon Film in Polymer Electroluminescence Devices%聚合物电致发光器件中用类金刚石碳膜增强电子注入

    Institute of Scientific and Technical Information of China (English)

    李宏建; 闫玲玲; 黄伯云; 易丹青; 胡锦; 何英旋; 彭景翠

    2006-01-01

    A diamond-like carbon (DLC) film is deposited as an electron injection layer between the polymer light-emitting layer (MEH-PPV) and aluminum (Al) cathode electrode in polymer electroluminescence devices (PLEDs) using a radio frequency plasma deposition system. The source material of the DLC is n-butylamine. The devices consist of indium tin oxide (ITO)/MEH-PPV/DLC/Al. Electron injection properties are investigated through I-V characteristics, and the mechanism of electron injection enhancement due to a thin DLC layer has been studied. It is found that: (1) a DLC layer thinner than 1. 0nm leads to a higher turn-on voltage and decreased electroluminescent (EL) efficiency; (2) a 5.0nm DLC layer significantly enhances the electron injection and re sults in the lowest turn-on voltage and the highest EL efficiency; (3) DLC layer that exceeds 5.0nm results in poor device performance; and(4) EL emission can hardly be detected when the layer exceeds 10.0nm. The properties ofITO/MEH-PPV/DLC/Al and ITO/MEH-PPV/LiF/Al are investigated comparatively.%用正丁胺作碳源,采用射频辉光等离子系统制备类金刚石碳膜(DLC),沉积在聚合物发光器件中的发光层(MEH-PPV)和铝(Al)阴极间作电子注入层.制备了结构为ITO/MEH-PPV/DLC/Al的不同DLC厚度的器件,测量了器件的I-V特性、亮度及效率,研究了DLC层对器件电子注入性能影响的机制.结果表明:当DLC厚度小于1.0nm时,其器件有较ITO/MEH-PPV/Al高的启动电压和低的发光效率;当DLC厚度在1.0~5.0nm之间时,器件的性能随着DLC厚度增加而变好;当DLC厚度为5.0nm时,器件具有最低的启动电压与最高的发光效率;当DLC厚度继续增加时,器件的性能随着DLC厚度增加而变差.并对ITO/MEH-PPV/DLC/Al和ITO/MEH-PPV/LiF/Al的器件性能进行了比较研究.

  2. Determination of eight nitrosamines in water at the ng L{sup -1} levels by liquid chromatography coupled to atmospheric pressure chemical ionization tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Ripolles, Cristina; Pitarch, Elena; Sancho, Juan V.; Lopez, Francisco J. [Research Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat, E-12071 Castellon (Spain); Hernandez, Felix, E-mail: felix.hernandez@qfa.uji.es [Research Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat, E-12071 Castellon (Spain)

    2011-09-19

    Highlights: {center_dot} Eight N-nitrosamines in water by LC(APCI)MS/MS QqQ analysis. {center_dot} Validation at two levels: 10 ng L{sup -1} (LOQ) and 100 ng L{sup -1} in drinking water. {center_dot} Developed method applied to different types of water samples. {center_dot} NDMA was the analyte more frequently detected and at the highest concentration levels. - Abstract: In this work, we have developed a sensitive method for detection and quantification of eight N-nitrosamines, N-nitrosodimethylamine (NDMA), N-nitrosomorpholine (NMor), N-nitrosomethylethylamine (NMEA), N-nitrosopirrolidine (NPyr), N-nitrosodiethylamine (NDEA), N-nitrosopiperidine (NPip), N-nitroso-n-dipropylamine (NDPA) and N-nitrosodi-n-butylamine (NDBA) in drinking water. The method is based on liquid chromatography coupled to tandem mass spectrometry, using atmospheric pressure chemical ionization (APCI) in positive mode with a triple quadrupole analyzer (QqQ). The simultaneous acquisition of two MS/MS transitions in selected reaction monitoring mode (SRM) for each compound, together with the evaluation of their relative intensity, allowed the simultaneous quantification and reliable identification in water at ppt levels. Empirical formula of the product ions selected was confirmed by UHPLC-(Q)TOF MS accurate mass measurements from reference standards. Prior to LC-MS/MS QqQ analysis, a preconcentration step by off-line SPE using coconut charcoal EPA 521 cartridges (by passing 500 mL of water sample) was necessary to improve the sensitivity and to meet regulation requirements. For accurate quantification, two isotope labelled nitrosamines (NDMA-d{sub 6} and NDPA-d{sub 14}) were added as surrogate internal standards to the samples. The optimized method was validated at two concentration levels (10 and 100 ng L{sup -1}) in drinking water samples, obtaining satisfactory recoveries (between 90 and 120%) and precision (RSD < 20%). Limits of detection were found to be in the range of 1-8 ng L{sup -1

  3. HPLC法测定馥感啉口服液中盐酸麻黄碱和盐酸伪麻黄碱的含量%Determination of Ephedrine Hydrochloride and Pseudoephedrine Hydrochloride in Fuganlin Oral Liquid by HPLC

    Institute of Scientific and Technical Information of China (English)

    曾永长; 张莉; 曾晓燕; 陈艺文

    2015-01-01

    目的:采用高效液相色谱法建立同时测定馥感啉口服液中盐酸麻黄碱和盐酸伪麻黄碱含量的检测方法。方法使用Phenomenex Synergi Polar-RP柱(250 mm×4.6 mm,4μm),以甲醇-0.092%磷酸溶液(含0.04%三乙胺和0.02%二正丁胺)(1.5∶98.5)为流动相,流速:1.0 mL·min-1,检测波长为210 nm。结果盐酸麻黄碱和盐酸伪麻黄碱在进样1~100μg·mL-1范围内线性关系良好,平均回收率(n=6)分别为97.43%(RSD=0.80%)、98.59%(RSD=1.77%)。结论该方法操作简便、分离度好、稳定可靠,可同时快速测定盐酸麻黄碱和盐酸伪麻黄碱,为馥感啉口服液的质量评价提供科学依据。%Objective To establish a HPLC method to determine the content of ephedrine hydrochloride and pseudoephedrine hydrochloride in Fuganlin oral liquid. Methods The chromatographic conditions was as follows:Phenomenex Synergi Polar-RP column(250 mm ×4.6 mm, 4 μm), methanol-0.092 % phosphoric acid solution (containing 0.04 % triethylamine and 0.02 % di-n-butylamine)(1.5∶98.5)as the mobile phase, flow rate being 1.0 mL ·min-1, detection wavelength set as 210 nm. Results The linear range of ephedrine hydrochloride and pseudoephedrine hydrochloride was 1~100 μg·mL-1,and the average recovery(n=6)was 97.43 % (RSD=0.80 %) and 98.59 %(RSD=1.77 %)respectively. Conclusion The method is simple,accurate and reliable,and can be used for the simultaneous determination of ephedrine hydrochloride and pseudoephedrine hydrochloride,which will provide a scientific basis for quality evaluation of Fuganlin oral liquid.

  4. HPLC测定克咳片中生物碱成分的含量%Content Determination of Alkaloids in Keke Tablets by HPLC

    Institute of Scientific and Technical Information of China (English)

    郑英昊; 鲁寅生

    2013-01-01

    Objective To establish the method for determining ephedrine hydochloride and pseudoephedrine hydrochloride in Keke Tablets by HPLC. Methods The samples were analyzed by a phemomenex Synergi Polar-RP column (4.6 mm×250 mm, 4 µm), with mobile phase methanol∶0.092%phosphoric acid (0.04%triethylamine and 0.02%second butylamine)=1.5∶98.5 at flow rate of 1.0 mL/min and detection at UV wavelength of 210 nm. The column temperature was 30 ℃. Results The linear ranges of ephedrine hydrochloride and pseudoephedrine hydrochloride were 6.51×10-3-0.651 µg (r=0.999 9) and 6.27×10-3-0.627 µg (r=1), respectively. The average recoveries (n=6) of ephedrine hydrochloride and pseudoephedrine hydrochloride were 102.26%and 103.71%, with RSD of 0.34%and 0.22%, respectively. Conclusion This method is simple, accurate, reproducible, highly specific and reliable results, and has the ability to effectively control the quality of alkaloids in Keke Tablets.%目的建立高效液相色谱法同时测定克咳片中盐酸麻黄碱、盐酸伪麻黄碱含量的方法。方法色谱柱:phenomenex Synergi Polar-RP柱(4.6 mm×250 mm,4µm);流动相:甲醇∶0.092%磷酸溶液(含0.04%三乙胺和0.02%二正丁胺)=1.5∶98.5;检测波长:210 nm;流速:1.0 mL/min;柱温:30℃。结果盐酸麻黄碱和盐酸伪麻黄碱的线性范围分别为6.51×10-3~0.651µg(r=0.9999)、6.27×10-3~0.627µg(r=1),平均加样回收率(n=6)分别为102.26%、103.71%,RSD 分别为0.34%、0.22%。结论该方法简便、准确,重复性好,专属性高,结果可靠,可有效控制克咳片中生物碱成分的质量。

  5. Synthesis of functionally graded materials via electrophoretic deposition and sintering

    Science.gov (United States)

    Wang, Xuan

    In this research, both the experiments and the modeling aspects of the net-shape fabrication of Functionally Graded Materials (FGM) by Electrophoretic Deposition (EPD) and consecutive sintering have been investigated. In order to obtain FGMs with desired final shape and properties, the issues regarding the shape evolution during sintering, the optimization of initial properties and composition profiles, and the fabrication of green components by EPD have been analyzed. In order to fabricate FGMs by the proposed technological sequence (EPD with the following sintering), the initial shape has to be optimized prior to sintering. In this research, the formulations to simulate sintering of an FGM were developed based on the continuum theory of sintering. A finite element sintering-modeling subroutine has been created and linked to the commercial finite element package ABAQUS. The shape changes of FGM disks during sintering were simulated. In order to obtain the desired final shape after sintering, an inverse modeling methodology was developed to optimize the initial shape. In order to fabricate the optimized initial shape of a green FGM specimen determined by the inverse continuum modeling of sintering, EPD of a number of FGMs was investigated. The FGM green specimens made of Al2O 3 and ZrO2 with the initial shape predicted by the inverse modeling, were deposited using self-designed equipments. The acetone-based suspension with n-butylamine as a particle-charging additive was used. The comparison of the shape between the sintered and the green FGM indicated that the developed experimental-theoretical methodology provided a reliable solution for near net shaping of complex 3-D FGM components. Other applications of EPD, such as in electronic packaging materials and zeolites, were also investigated. In order to fabricate functionally graded materials based on aligned porous structures, unidirectional freezing followed by freeze-drying and sintering has been investigated

  6. Experiment Study on a Low Grade Copper-molybdenum Ores%某低品位铜钼矿石选矿试验

    Institute of Scientific and Technical Information of China (English)

    胡志刚; 代淑娟; 孟宇群; 邵坤

    2012-01-01

    Molybdenum and copper content in a copper-molybdenum ores is low, Cu-content is 0.081% and Mo-content is 0.19%. The disseminated size of Cu minerals is fine and symbiosis with molybdenum ores, that lake difficult to separation of Cu and Mo. By using the flowsheet of bulk flotation of Cu and Mo, regrinding and re-concentrantion after mixed concentrate cleaned, and then separation of Cu and Mo, the experiment index of concentrate grade of Mo at 45.30% , the recovery of Mo at 84. 16% , the concentrate grade of Cu at 14.28% , die recovery of Cu at 89. 59% were got on the condition of the size of the first and the second grinding each - 0.074 mm 70% , -0.045 mm 95% , using lime, sodium silicate as modifier, using butylamine black agent and kerosene as collector in the mix-flotation, using lime, water glass and SK as the modifier, using kerosene as collector in the separation flowsheet of Cu and Mo.%某铜钼矿石中钼和铜含量较低,分别为0.081%和0.19%,且铜矿物嵌布粒度较细并与钼矿物密切共生,给两者分离带来一定困难.采用钼铜混合浮选—混合精矿精选1次后再磨再精选—铜钼分离流程对该矿石进行选矿试验,混合浮选时以石灰和水玻璃为调整剂、煤油和丁铵黑药为捕收剂,铜钼分离时以石灰、水玻璃和SK为调整剂、煤油为捕收剂,在1段和2段磨矿细度分别为-0.074 mm占70%和-0.045 mm占95%条件下,获得了钼品位为45.30%、钼回收率为84.16%的钼精矿和铜品位为14.28%、铜回收率为89.59%的铜精矿,为该矿石的开发提供了技术依据.

  7. In-situ Studies of the Reactions of Bifunctional and Heterocyclic Molecules over Noble Metal Single Crystal and Nanoparticle Catalysts Studied with Kinetics and Sum-Frequency Generation Vibrational Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kliewer, Christopher J. [Univ. of California, Berkeley, CA (United States)

    2009-06-30

    Sum frequency generation surface vibrational spectroscopy (SFG-VS) in combination with gas chromatography (GC) was used in-situ to monitor surface bound reaction intermediates and reaction selectivities for the hydrogenation reactions of pyrrole, furan, pyridine, acrolein, crotonaldehyde, and prenal over Pt(111), Pt(100), Rh(111), and platinum nanoparticles under Torr reactant pressures and temperatures of 300K to 450K. The focus of this work is the correlation between the SFG-VS observed surface bound reaction intermediates and adsorption modes with the reaction selectivity, and how this is affected by catalyst structure and temperature. Pyrrole hydrogenation was investigated over Pt(111) and Rh(111) single crystals at Torr pressures. It was found that pyrrole adsorbs to Pt(111) perpendicularly by cleaving the N-H bond and binding through the nitrogen. However, over Rh(111) pyrrole adsorbs in a tilted geometry binding through the {pi}-aromatic orbitals. A surface-bound pyrroline reaction intermediate was detected over both surfaces with SFG-VS. It was found that the ring-cracking product butylamine is a reaction poison over both surfaces studied. Furan hydrogenation was studied over Pt(111), Pt(100), 10 nm cubic platinum nanoparticles and 1 nm platinum nanoparticles. The product distribution was observed to be highly structure sensitive and the acquired SFG-VS spectra reflected this sensitivity. Pt(100) exhibited more ring-cracking to form butanol than Pt(111), while the nanoparticles yielded higher selectivities for the partially saturated ring dihydrofuran. Pyridine hydrogenation was investigated over Pt(111) and Pt(100). The α-pyridyl surface adsorption mode was observed with SFG-VS over both surfaces. 1,4-dihydropyridine was seen as a surface intermediate over Pt(100) but not Pt(111). Upon heating the surfaces to 350K, the adsorbed pyridine changes to a flat-lying adsorption mode. No evidence was found for the pyridinium cation. The hydrogenation of the

  8. The Influences of Surface Passivation on Luminescence Properties of Porous Silicon%多孔硅表面钝化对其发光性能的影响

    Institute of Scientific and Technical Information of China (English)

    李宏建; 瞿述; 剪之渐; 彭景翠; 向建南

    2000-01-01

    By using n-butylamine as carbon resource,a layer of carbon film is covered on the parous silicon(PS)surface by means of radio frequency glow discharge.Raman spectra and IR spectra of the carbon film indicate that there are amino-groups and hydrogen atoms in the carbon film.IR spectra exhibits that the surface of the treated sample is mainly covered with Si-C,Si-N and Si-O.The influences of surface passivation of photoluminescence and electroluminescence properties of porous silicon have been presented.PL and EL spectra indicate that PL and EL intensity of the treated samples increase greatly and the blueshift of PL and EL peak compared with the samples without treatment and stable while storing in atmosphere.I~V characteristics reveal that the treated devices have a lower onset voltage.We present that the enhancement of the PL and EL intensity、stability and lower onset voltage of the treated sample is due to the existence of Si-C,Si-N and Si-O on the PS surface simultaneously,and blueshift of the PL and El peak are attributed to amino-groups and hydrogen atmos in the carbon film,As a result,carbon film passivation is a good way to enhance PS luminescent intensity and stability and improve the properties of PS devices.%报道多孔硅(PS)的表面钝化对其光致发光(PL)和电致发光(EL)的影响。PL和EL谱表明,经钝化处理的PS的PL和EL强度明显增强,且发光峰位较大蓝移;存放实验表明,经钝化处理的PS的PL和EL发光强度和发光峰位具有较好的稳定性;I~V曲线显示,经钝化处理的PS发光器件具有较低的启动电压。这些结果表明:用钝化处理的方法是提高PS的PL和EL强度和稳定性及改善其器件性能的有效途径。

  9. N-正丁基-1-脱氧野尻霉素合成方法的改进%An improved strategy to synthesize N-butyl-1-deoxynojirimycin

    Institute of Scientific and Technical Information of China (English)

    王佳佳; 张振兴; 李铁海; 郭利娜; 刘艳坤; 赵炜

    2011-01-01

    As an amino sugar derivative,N-butyl-1-deoxynojirimycin has promising therapeutics in treatment of diabetes, viral infections, metastatic cancers and Gancher's diseases. Low yield is the main obstacle for chemical synthetic of N-butyl-1-deoxynojirimycin. To improve the synthetic procedure,butyryl group was introduced to the nitrogen atom of 2,3,4,6-tetra-O-benzyl-D-gluconolactam (5) using butyryl chloride or buty-ric anhydride, respectively. The resulting compound N-butyryl-2,3,4,6-tetra-O-benzyl-D-gluconolac-tam(6) was treated with aluminium hydride to afford N-butyl-2,3,4,6-tetra-O-benzyl-deoxynojirimycin(7) in a satisfying yield. Compared with the previously reported synthetic strategy (yield of 23.4% ) ,the developed method can significantly increase the yield(54% ) from compound 5 to 7. In summary,we have successfully optimised the synthetic procedures of N-butyl-1-deoxynojirimycin. Besides, instead of methanolic ammonia,n-butylamine was used for ammonolysis,expected product and possible mechanism of forming the byproduct were discussed in the ring-close step.%目的 改进N-正丁基-1-脱氧野尻霉素的合成.方法:该文通过酰化反应分别用丁酰氯和丁酸酐将丁酰基引入到2,3,4,6-四苄基葡萄糖内酰胺的氮原子上,然后用氢化铝锂将两个羰基还原,得到N-正丁基-2,3,4,6-四苄基-1-脱氧野尻霉素.结果与结论该.方法:在改进部分将收率提高为相关文献的2~3倍,在氨解开环这一步,尝试用正丁基胺代替饱和氨气的甲醇溶液,并对其关环产物以及副产物的生成机制进行了探讨.

  10. Inhibition Evaluation of Common Small Molecule Inhibitors of CCR5 for HIV%HIV辅助受体CCR5常见小分子抑制剂抑制效果的综合评价

    Institute of Scientific and Technical Information of China (English)

    焦诗卉; 何淼

    2012-01-01

    The study endeavors to find the optimal inhibitor and the best poses of CCR5 for HIV by comparing the inhibition of common small molecule inhibitors systematically. The results will be helpful to design new drugs of inhibitors. The 3D structures of 29 kinds of small molecule inhibitors from 7 classes were built by using Material Studio software The docking results that each inhibitor docks with CCR5 protein were obtained. Several parameters had been used to evaluate the inhibition effects of these molecules , which include absolute free energy, relative free energy, docking attitude percentage and LibDock composite score et al. And finally the study also revealed the optimal site of CCR5 which located in the second cell outer ring and the N-terminal. The inhibitions from strong to weak are sorted as following; Inhibitor 27 (pyrrolidine) , inhibitors ( benzo cycloheptane vinyl) , inhibitor 12 (piperidine) , inhibitor 14 ( spiro diketone piperidine), inhibitor 21 (4-piperazine pyridine-1-the butylamine class), 5 inhibitors (natural small molecule class), inhibitor 17 (tropicamide alkanes). Among which, inhibitor 27 (pyrrolidine) may be the candidate of optimal inhibitor of CCR5 protein.%通过系统比较CCR5常见小分子抑制剂的抑制效果,寻找CCR5的优化对接靶点,筛选最优抑制剂,为新型抑制剂的研发提供理论依据.基于Material Studio软件,我们构建了7类29种小分子抑制剂的三维结构,全面模拟了各种抑制剂与CCR5对接的效果;利用分子对接绝对自由能、相对自由能、对接姿态百分比和LibDock综合得分等参数评估小分子抑制剂的抑制效果.研究初步发现,CCR5小分子抑制剂的最优对接位点是第二个胞外环与N末端之间的site4.小分子抑制剂的抑制效果由强到弱排序依次为:抑制剂27(吡咯烷类)、抑制剂8(苯并环庚烯类)、抑制剂12(哌啶类)、抑制剂14(螺环二酮哌啶类)、抑制剂21(4-哌啶-1-丁胺类)、抑制剂5(

  11. 有机胺法制备氢氧化镁及其阻燃性能%Preparation and Its Antiflaming Properties of Magnesium Hydroxide by Organic-Amine Method

    Institute of Scientific and Technical Information of China (English)

    汪苏平; 海吉忠; 杨小波; 张志君; 吴江渝; 陈喆; 张勇

    2016-01-01

    Magnesium hydroxide was prepared by using di-n-butylamine as a precipitating agent instead of the traditional inorganic basic precursor. The reaction conditions were optimized by employing the single variable method. The morphology and particle size of the obtained magnesium hydroxide were characterized, and its anti⁃flaming mechanism was investigated. The results show that the optimal experimental conditions for the prepara⁃tion of magnesium hydroxide are as follows:reaction temperature of 70℃, reaction time of 50 minutes, and stir⁃ring rate of 400 r/min. The magnesium hydroxide has a form of lamellar crystal with an average diameter of 1.8μm, and its performances meet the industrial requirements. The precipitant can be recovered and recycled, thus this method is expected to improve the traditional technology for magnesium hydroxide preparation. The results of thermal gravimetric analysis and simulated combustion test suggest that the antiflaming mechanism of magne⁃sium hydroxide can be ascribed to:it improves the thermal decomposition temperature of the used materials, and the magnesium oxide produced by the decomposition of magnesium hydroxide with the carbon forms a layer to achieve thermal insulation and oxygen exclusion.%以二正丁胺代替传统无机碱性前驱物作为沉淀剂的方法制备氢氧化镁.通过控制单一变量法,得到了最佳的实验条件,对氢氧化镁产品进行了形貌表征和粒径分析,并对氢氧化镁的阻燃机理进行了探索.研究表明,通过该方法制备氢氧化镁的最佳实验条件为:反应温度70℃左右,反应时间50 min左右,搅拌速率400 r/min;制得的氢氧化镁为片状结晶,尺寸在1.8μm左右,产品各项性能符合当前工业要求,且沉淀剂可回收二次利用,有望改善氢氧化镁的传统制备工艺.通过热重分析与模拟燃烧实验,推测氢氧化镁的阻燃机理为:一方面提高了材料的热分解温度,另一方

  12. Simultaneous determination of five psychoactive drugs in overdosed patients serum by high performance liquid chromatography%高效液相色谱法同时测定中毒患者血清中5种精神活性物质的浓度

    Institute of Scientific and Technical Information of China (English)

    果伟; 赵晔; 郭桂欣; 张军; 孙川; 荣璋; 段晓霞; 李文标; 翟屹民

    2013-01-01

    Objective A high performance liquid chromatography ( HPLC) method with ultraviolet ( UV) detection ( 230 nm) was developed and validated for the quantification of 5 drugs, Risperidone, clozapine, reboxetine, 9-hydroxy Risperidone and norclozapine, in human serum. Methods Following a one-step liquid-liquid extraction with diethyl ether, the analyte and internal standard ( paroxetine) were separated using an isocratic mobile phase consisted of acetonitrile :methanol :butylamine '-acetic acid :deionized water = 20:2. 9:1. 1: 1=34. 3 on a reverse phase Inertsil CIB-3 column. Five drugs and IS were separated well under the chromatographic condition. The calibration curve was verified over the range of 100 - 1 600 μg/L and limit of detection( LOD) was 25 μg/L( S/N= 10). Results The imprecision of within and between batches were 3. 1% ~ 15.6% and 5.7% ~ 18.4% , respectively. The accuracy of within and between batches were 0. 1% ~ 8. 7% and 0. 3% ~13. 3%. Commonly used psychotropic drugs did not interfere with the drugs and internal standard. Conclusion This method was found to be rapid, simple, accurate, sensitive and more suitable for rapid qualitative and quantitative determination of drugs in the serum of overdosed patients.%目的 建立可同时测定人血清中利培酮、9-羟利培酮、氯氮平、去甲氯氮平和瑞波西汀5种药物浓度的高效液相色谱-紫外检测法,并将该方法用于临床急性精神药物中毒患者的血液样本分析.方法 以乙醚为溶剂进行一步液液萃取,待测物与内标帕罗西汀在Inertsil ODS-3柱,乙腈∶甲醇∶正丁胺∶冰醋酸∶去离子水(20∶2.87∶1.07∶1∶34.29)条件下可以基线分离.线性范围100 ~1 600 ng/mL,最低检测限25 μg/L(S/N=10).结果 本方法批内精密度为3.1% ~ 15.6%,批间精密度为5.7% ~18.4%;批内准确度为0.1% ~8.7%,批间准确度为0.3% ~13.3%.常见精神科药物不干扰待测药物和内标.结论 本方法简单

  13. 提高多孔硅传感特性的一种新方法%A New Method For Improving Sensing Characteristics of Porous Silicon

    Institute of Scientific and Technical Information of China (English)

    李宏建; 崔昊杨; 黄伯云; 易丹青; 何英旋; 彭景翠

    2004-01-01

    The luminescence quenching effect of porous Si caused by adsorbing organic moleculars are investigated. It indicates that the solvent molecules of quenching luminescence are polarized molecules and the different polarity determines the different quenching, and the quenching caused by molecules absorbed of oxide porous Si has better reversibility and selectivity than that of porous Si. By using n-butylamine as carbon resource, carbon-nitrogen (c-n) film was deposited on the p-n junction(p- n) porous Si surface by means of a radio-frequency glow discharge plasma system. Electroluminescence (EL) intensity enhancement and EL peak blueshift of the passivated porous Si are observed experimentally. Further, the intensity decay and the peak blueshift of porous Si are not observed after storing 60 days in the atmosphere. The current-voltage characteristics show that the series resistance Rs and driven voltage in the ITO/cn/p-n porous Si diode is reduced greatly compared with the ITO/p-n porous Si diode. It provides a new method for improving sensing characteristics of porous Si.%研究了多孔硅(PS)吸附有机溶剂分子后对多孔硅荧光谱的淬灭效应.结果表明:淬灭多孔硅发光的有机溶剂分子是极性分子,有机溶剂分子的极性不同对多孔硅发光的淬灭程度也不同,且有些有机溶剂分子吸附氧化多孔硅比吸附多孔硅引起的发光淬灭具有更好的可逆性和选择性;用含有胺基的正丁胺(CH3CH2CH2CH2-NH2)作碳源,用射频辉光放电等离子系统在多孔硅表面沉积c-n膜对多孔硅进行钝化处理后发现:其电致发光强度明显增强,发光峰位兰移,且在大气中存放60天后,其电致发光谱强度基本不衰减,峰位不再移动.经钝化处理的器件较未经处理的器件具有小的串联电阻R和低的驱动电压.这为提高多孔硅的传感特性提供了一种新方法.

  14. 水溶性非离子螯合捕收剂合成技术研究报告%Study on Synthesis Technology of Water Soluble and Nonionic Chelating Collector

    Institute of Scientific and Technical Information of China (English)

    王永斌

    2016-01-01

    /mL, the main component content is no less than 85%. It is effective collector for natural copper, gold and sulfide of copper, nickel,lead and zinc.This reagent has the good double excellent properties with collecting power and selectivity, especially for fine grained copper content,it has a strong ability of collecting, and with a wide pH range, as pH7~12. Ashele Copper ore dressing experiments in xinjiang show that, In the case of guarantee grade of copper concentrate,compared to the original plan, Copper recovery rate increased by 2.65%.Through compound With Sulfur nitrogen acrylic ester,non-ionic collector,A-300 and so on,this topic get two of single-minded collector with A-6 and A-9,which has a strong ability of collecting for copper mineral.The agent of A-6 can greatly improve the recovery rate of copper mineral,which has A strong ability of collecting for copper mineral intergrowth.A-6 instead of the original drug in copper concentrator of Saishitang and BaiNaimiao,the remarkable technical indexes have obtained: the copper concentrate grade from 14.42% to 14.42%, copper recovery rate increased by 2.23%.Using A-9 collecting frother to replace the agent of 2# oil and butylamine in a low-grade copper and nickel ore of Yakesi in xinjiang, the ideal technical indexes are achieved: on the basis of original indexes, the recovery rate of nickel in the Copper and nickel concentrate is increased by 2.50%, copper recovery rate increased by 1.20%.

  15. Surveillance and Drug Resistance Analysis of Acinetobacter Sp. and Pseudomonas Aeruginosa Infection in a Hospital From 2013 to 2014%某院2013~2014年鲍曼不动杆菌及铜绿假单胞菌全院感染性监测及耐药性分析

    Institute of Scientific and Technical Information of China (English)

    崔敬惠

    2016-01-01

    Objective To explore the surveil ance and drug resistance of non fermenting bacteria acinetobacter bauman and pseudomonas aeruginosa in our hospital. Methods All kinds of various specimens from inpatient and outpatient were isolated and cultured and identified from January 2013 to December 2014 .The drug resistance of pathogenic bacteria was analyzed by using-NET 5.4 software in the world health organization(WHO). Results Bauman was divided into 312 strains of acinetobacter,1 364 pseudomonas aeruginosa from 2013 to 2014,most specimens were from sputum,the source of most clinical department is ICU,followed by department of respiration. pseudomonas aeruginosa resistant to compound sulfamethoxazole was 3.3%,for butylamine card that mildew,tobramycin,cefoperazone/sulbactam and levofloxacin resistance rate were 5%,5.3%, 5.5% and 9.4%,resistant to minocycline,ceftriaxone,cefotaxime was higher,respectively 56.8%,55.3%,45.6%,the resistance rate to other antimicrobial agents was 10% ~ 30%,bauman acinetobacter resistance to minocycline was 4.2%,to cefoperazone/sulbactam was 11.4%,to compound sulfamethoxazole resistance was the highest,was 51.9%,the drug resistance rate of other common drugs was 30% ~ 50%. Conclution The infection of pseudomonas aeruginosa and bauman is widespread,and the drug resistance is obvious. Clinical should strengthen the monitoring of drug resistance of these two kinds of hospital to prevent the spread of resistant strains.%目的:对我院常见的非发酵菌鲍曼不动杆菌和铜绿假单胞菌进行感染性监测并且对其耐药性进行分析。方法收集2013年1月~2014年12月住院和门诊患者送检的各类标本并进行分离培养和鉴定;采用世界卫生组织(WHO)-NET5.4软件对病原菌的耐药性进行分析。结果2013~2014年共分出鲍曼不动杆菌312株,铜绿假单胞菌1364株。标本来源均以痰液为主,临床科室来源最多的是 ICU,其次是呼吸科。铜绿假单胞菌对复

  16. 尿路感染大肠埃希菌遗传种系分型及其耐药性的相关性探讨%Escherichia coli urinary tract infection germ line genetic typing and correlation of drug resistance

    Institute of Scientific and Technical Information of China (English)

    梅俪凡; 王荣聪; 焦石

    2015-01-01

    Objective To investigate different E.coli urinary tract infection germ line genetic typing and drug resistance of relevance.Methods Select our hospital between January 2013 and March 2014 separation of 122 strains within 48 h after admission e.coli urinary tract infection and 108 strains after 48 h after admission urinary tract infection e.coli as a clinical research objects,all samples are selected from mid-stream specimen of urine,urinary tract infection patients with isolated within 48 h after admission in patients with urinary tract infection e.coli as a community infected bacteria,isola-ted after 48 h after admission in patients with urinary tract infection e.coli bacteria for hospital infec-tion,mining API20E enterobacteriaceae bacteria identification kit with the French company ATB mi-crobial identification of strains,semi-automatic analyzer with producer diffusion method determination of urinary tract infection of e.coli drug sensitivity,contrast different genetic types of tie points urina-ry tract infections e.coli resistance,produce broad-spectrum beta lactamase(extended spectrum beta lactamases,ESBLs ) rate and the distribution of infection in hospital and community infection. Results Among the 230 strains of Escherichia coli,138 strains of producing strains were detected, and 34 strains of ESBLs and AmpC were detected by ESBLs76 and AmpC.230 strains of Escherichia coli to antibiotics resistance:resistance to commonly used antibiotics in clinic from top to bottom in turn:cotrimoxazole 81 .7%,piperacillin,pull Westwood 76.7%,74.2% of ampicillin,ampicillin sul-bactam 61 .7%,butylamine card that mildew element 61 .7%,cefuroxime 60.8%,cephalosporins cef-podoxime 59.2%,ammonia aztreonam 59.2%,pethidine pull Xin Lin He cling to Zun 32.5%,ce-fazolin 68.3%,gentamicin 57.5%,cephalosporins cefotaxime 43.3%,cefotaxime cefepime 38.3%, cefotaxime and 33.3% of cefoxitin,imipenem 0.8%.①According to the test results,and no bacterial infection in the community and