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Sample records for preparing natural benzaldehyde

  1. β-Cyclodextrin Promoted Oxidation of Cinnamaldehyde to Natural Benzaldehyde in Water

    Institute of Scientific and Technical Information of China (English)

    陈鸿雁; 纪红兵

    2011-01-01

    A facile and efficient procedure has been developed systematically for the oxidative cleavage of cinna-maldehyde to benzaldehyde by sodium hypochlorite with water as the only solvent in the presence of β-cyclodextrin (abbreviated as β-CD). Different factors influencing cinnamaldehyde oxidation e.g. reaction temperature, the amount of catalyst and oxidant, have been investigated. The yield of benzaldehyde reaches 76% under the optimum conditions (333 K, 4 h, molar ratio of cinnamaldehyde to β-CD is 1:1). Furthermore, a feasible reaction mecha-nism including the formation of benzaldehyde and the two main byproducts (phenylacetaldehyde and epoxide of cinnamaldehyde) has been proposed.

  2. Preparation of benzyl-[alpha]-D[sub 1]-alcohol by the reduction of benzaldehyde with Raney alloys in an alkaline deuterium oxide solution

    Energy Technology Data Exchange (ETDEWEB)

    Tsukinoki, Takehito; Mataka, Shuntaro; Tashiro, Masashi (Kyushu Univ. (Japan). Inst. of Advanced Material Study); Ishimoto, Keiko (Kyushu Univ. (Japan). Graduate School of Engineering Sciences); Tsuzuki, Hirohisa (Kyushu Univ., Fukuoka (Japan). Center of Advanced Instrumental Analysis)

    1993-10-01

    Benzyl-[alpha]-d[sub 1]-alcohol was prepared in high isotopic purity by the reduction of benzaldehyde with Raney Cu-Al alloy in 10% Na[sub 2]CO[sub 3]-D[sub 2]O solution using ultrasonic irradiation. (Author).

  3. Preparation and characterization of new and improved soluble-starches, -amylose, and -amylopectin by reaction with benzaldehyde/zinc chloride.

    Science.gov (United States)

    Johnston, David A; Mukerjea, Rupendra; Robyt, John F

    2011-12-13

    Seven different starches from potato, rice, maize, waxymaize, amylomaize-VII, shoti, and tapioca, and potato amylose and potato amylopectin have been reacted with benzaldehyde, catalyzed by ZnCl(2), to give new water-soluble starches and water soluble-amylose and soluble-amylopectin. In contrast to the native starches, aqueous solutions of the modified starches could not be precipitated with 2-, 3-, or 4-volumes of ethanol. β-Amylase gave no reaction with the modified starches, in contrast to the native starches, indicating that the modification occurred exclusively at the nonreducing-ends, giving 4,6-benzylidene-D-glucopyranose at the nonreducing-ends. Reactions of α-amylase with native and modified potato and rice starches gave a decrease in the triiodide blue color and an increase in the reducing-value that were similar for the native- and modified-starches, indicating the modified starches had not been significantly altered by the modification. The benzaldehyde-modified starches and benzaldehyde-modified potato amylose and potato amylopectin components, therefore, have a starch structure very much like their native counterparts, in contrast to the Lintner, Small, and the alcohol/acid-hydrolyzed soluble-starches that have undergone acid hydrolysis. The benzaldehyde-modified starches and starch components have significantly higher water solubility than their native counterparts even though the structures of the modified starches had only been slightly altered from the structures of their native counterparts. They all gave crystal-clear solutions that did not retrograde.

  4. MCM-41 supported 12-tungstophosphoric acid mesoporous materials: Preparation, characterization, and catalytic activities for benzaldehyde oxidation with H2O2

    Science.gov (United States)

    Chen, Ya; Zhang, Xiao-Li; Chen, Xi; Dong, Bei-Bei; Zheng, Xiu-Cheng

    2013-10-01

    Mesoporous molecular sieves MCM-41 and bulk 12-tungstophosphoric acid (HPW) were synthesized and employed to prepare 5-45 wt.% HPW/MCM-41 mesoporous materials. Characterization results suggested the good dispersion of HPW within MCM-41 when the loading of HPW was less than 35 wt.% and HPW/MCM-41 retained the typical mesopore structure of the supports. The results of the catalytic oxidation of benzaldehyde to benzoic acid with 30% H2O2, in the absence of any organic solvent and co-catalysts, indicated that HPW/MCM-41 was an efficient catalyst and 30 wt.% HPW/MCM-41 sample exhibited the highest catalytic activity among these materials.

  5. Lanthanide-surfactant-combined catalysts for the allylation of benzaldehyde with tetraallyltin in aqueous solutions

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    Deleersnyder, Karen; Shi Danzhao; Binnemans, Koen [Katholieke Universiteit Leuven, Department of Chemistry, Laboratory of Coordination Chemistry, Celestijnenlaan 200F, B-3001 Leuven (Belgium); Parac-Vogt, Tatjana N. [Katholieke Universiteit Leuven, Department of Chemistry, Laboratory of Coordination Chemistry, Celestijnenlaan 200F, B-3001 Leuven (Belgium)], E-mail: Tatjana.Vogt@chem.kuleuven.be

    2008-02-28

    Metal-surfactant-combined catalysts having the general formula M(DOS){sub x} (DOS = dodecylsulfate), x = 1-3, can be used for the efficient allylation of benzaldehyde with tetraallyltin in water. Due to the formation of micelles the reaction proceeds in the absence of organic solvents. Examination of a series of lanthanide(III) and divalent transition-metal dodecylsulfates as catalysts for the reaction between benzaldehyde and tetraallyltin revealed that the highest yields can be obtained when lanthanide(III) and copper(II) salts are used. Within 6 h at room temperature nearly quantitative conversion of benzaldehyde to 1-phenyl-3-buten-1-ol was achieved in the presence of 10 mol% of Cu(DOS){sub 2} or Yb(DOS){sub 3}. The influence of the amount of catalyst and tetraallyltin on the reaction yield was investigated. Different alkylsulfates, alkylsulfonates and arylsulfonates metal salts were prepared and tested as catalysts in the allylation reaction. The highest yields were obtained with ytterbium(III) alkylsulfates and ytterbium(III) arylsulfonates, while ytterbium(III) alkylsulfonates were found to be poor allylation catalysts. The results show that both the nature of the metal cation as well as the length and the nature of anionic surfactant chain are crucial for the activity of the metal-surfactant-combined catalysts in water.

  6. Case study: Natural bodybuilding contest preparation.

    Science.gov (United States)

    Kistler, Brandon M; Fitschen, Peter J; Ranadive, Sushant M; Fernhall, Bo; Wilund, Kenneth R

    2014-12-01

    The purpose of this study was to document the physiological changes that occur in a natural bodybuilder during prolonged contest preparation for a proqualifying contest. During the 26-week preparation, the athlete undertook a calorically restrictive diet with 2 days of elevated carbohydrate intake per week, increased cardiovascular (CV) training, and attempted to maintain resistance-training load. The athlete was weighed twice a week and body composition was measured monthly by DXA. At baseline and every 2 weeks following CV structure and function was measured using a combination of ultrasound, applanation tonometry, and heart rate variability (HRV). Cardiorespiratory performance was measured by VO(2)peak at baseline, 13 weeks, and 26 weeks. Body weight (88.6 to 73.3 Kg, R(2) = .99) and percent body fat (17.5 to 7.4%) were reduced during preparation. CV measurements including blood pressure (128/61 to 113/54 mmHg), brachial pulse wave velocity (7.9 to 5.8m/s), and measures of wave reflection all improved. Indexed cardiac output was reduced (2.5 to 1.8L/m(2)) primarily due to a reduction in resting heart rate (71 to 44 bpm), and despite an increase in ejection faction (57.9 to 63.9%). Assessment of HRV found a shift in the ratio of low to high frequency (209.2 to 30.9%). Absolute VO2 was minimally reduced despite weight loss resulting in an increase in relative VO2 (41.9 to 47.7 ml/Kg). In general, this prolonged contest preparation technique helped the athlete to improve body composition and resulted in positive CV changes, suggesting that this method of contest preparation appears to be effective in natural male bodybuilders.

  7. The Kinetic Behavior of Benzaldehyde under Hydrothermal Conditions

    Science.gov (United States)

    Fecteau, K.; Gould, I.; Hartnett, H. E.; Williams, L. B.; Shock, E.

    2013-12-01

    Aldehydes represent an intermediate redox state between alcohols and carboxylic acids and are likely intermediates in the transformation of organic compounds in natural systems. We have conducted kinetic studies of a model aldehyde, benzaldehyde, in high-temperature water (250-350 °C, saturation pressure) in clear fused quartz (CFQ) autoclaves. Under these conditions, benzaldehyde is observed to undergo a disproportionation reaction to benzyl alcohol and benzoic acid reminiscent of the base-catalyzed Cannizzaro reaction known to occur at cooler temperatures. Benzene is also produced via decarbonylation of the aldehyde. We have obtained pseudo second-order rate constants for the decomposition of benzaldehyde at 250, 300, and 350 °C. Rates derived via repeated heating phases and subsequent quantitative 13C-NMR spectroscopy of a single NMR-compatible CFQ tube containing isotopically labeled benzaldehyde are consistent with those obtained by analysis of product suites from individual timed experiments via gas chromatography. Arrhenius parameters for these rate constants are consistent with published values for the reaction under supercritical conditions from one study (Tsao et al. 1992) yet the pre-exponential factor is approximately 7 orders of magnitude smaller than that derived from another study (Ikushima et al. 2001). Moreover, fitting our rate constants with the Eyring equation yields an entropy of activation (ΔS‡) of -26.6 kcal mol-1 K-1, which is consistent for a bimolecular transition state at the rate-limiting step. In contrast, the rates of Ikushima et al. yield a positive value of ΔS‡, which is inconsistent with the putative mechanism for the reaction. The linear Arrhenius behavior of the decomposition of benzaldehyde from high-temperature liquid to supercritical conditions demonstrates the potential for extrapolating experimentally derived rates of reactions for organic functional group transformations to conditions where diagenesis, alteration

  8. Cherry-flavoured electronic cigarettes expose users to the inhalation irritant, benzaldehyde.

    Science.gov (United States)

    Kosmider, Leon; Sobczak, Andrzej; Prokopowicz, Adam; Kurek, Jolanta; Zaciera, Marzena; Knysak, Jakub; Smith, Danielle; Goniewicz, Maciej L

    2016-04-01

    Many non-cigarette tobacco products, including e-cigarettes, contain various flavourings, such as fruit flavours. Although many flavourings used in e-cigarettes are generally recognised as safe when used in food products, concerns have been raised about the potential inhalation toxicity of these chemicals. Benzaldehyde, which is a key ingredient in natural fruit flavours, has been shown to cause irritation of respiratory airways in animal and occupational exposure studies. Given the potential inhalation toxicity of this compound, we measured benzaldehyde in aerosol generated in a laboratory setting from flavoured e-cigarettes purchased online and detected benzaldehyde in 108 out of 145 products. The highest levels of benzaldehyde were detected in cherry-flavoured products. The benzaldehyde doses inhaled with 30 puffs from flavoured e-cigarettes were often higher than doses inhaled from a conventional cigarette. Levels in cherry-flavoured products were >1000 times lower than doses inhaled in the workplace. While e-cigarettes seem to be a promising harm reduction tool for smokers, findings indicate that using these products could result in repeated inhalation of benzaldehyde, with long-term users risking regular exposure to the substance. Given the uncertainty surrounding adverse health effects stemming from long-term inhalation of flavouring ingredients such as benzaldehyde, clinicians need to be aware of this emerging risk and ask their patients about use of flavoured e-cigarettes.

  9. Muonium adducts of benzaldehyde: Structural correlation with nitroxides

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    Rhodes, C.J. [John Moores University, School of Pharmacy and Chemistry (United Kingdom); Reid, I.D. [Paul Scherrer Institute (Switzerland); Jackson, R.A. [University of Sussex, School of Chemistry and Molecular Sciences (United Kingdom)

    1997-04-15

    We have formed adduct radicals (ArCHOMu{center_dot}) by muonium addition to the carbonyl group of benzaldehyde and its derivatives. The muon coupling is found to be highly sensitive to the nature of substituents in the benzene ring, being increased by electron releasing groups. Similarly, the {sup 14}N coupling in a series of nitroxides [ArN(O{center_dot})OSiEt{sub 3}], measured using ESR spectroscopy, is increased by electron releasing substituents and a linear correlation is found between the two; their connected nature is discussed.For the radical derived from benzaldehyde itself, a strong dependence is also found on the solvent in which it is solved. We suggest that this may be used in the study of solvent effects, particularly H-bonding, pertinent to organic and bioorganic media.

  10. Identification of isotopically manipulated cinnamic aldehyde and benzaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Culp, R.A.; Noakes, J.E. (Univ. of Georgia, Athens (USA))

    1990-05-01

    Cinnamic aldehyde and benzaldehyde samples were isolated from botanical sources and compared to labeled isolates from natural origins and those synthetically produced. Products synthesized from petrochemical precursors yielded {delta}{sup 13}C and {delta}D values uniquely different from those of botanical derivation. Upon further comparison with the radiocarbon ({sup 14}C) activities it was possible to define average {delta}{sup 13}C and {delta}D isotopic values for the naturally derived cinnamic aldehyde ({minus}27.6 {plus minus} 0.6 and {minus}116 {plus minus} 8, respectively) and benzaldehyde samples ({minus}28.6 {plus minus} 0.5 and {minus}105 {plus minus} 5, respectively) and the synthetically derived cinnamic aldehyde ({minus}25.4 {plus minus} 0.3 and 517 {plus minus} 52, respectively, via toluene oxidation) and benzaldehyde samples ({minus}29.2 {plus minus} 0.8 and {minus}54 {plus minus} 11, respectively, via benzal chloride and {minus}26.1 {plus minus} 0.6 and 576 {plus minus} 73, respectively, via toluene oxidation). It is also revealed by comparison of isotopic values for certain synthetically derived compounds that {sup 14}C manipulation of simulated natural products has occurred.

  11. delta(13)C and delta(2)H isotope ratios in amphetamine synthesized from benzaldehyde and nitroethane.

    Science.gov (United States)

    Collins, Michael; Salouros, Helen; Cawley, Adam T; Robertson, James; Heagney, Aaron C; Arenas-Queralt, Andrea

    2010-06-15

    Previous work in these laboratories and by Butzenlechner et al. and Culp et al. has demonstrated that the delta(2)H isotope value of industrial benzaldehyde produced by the catalytic oxidation of toluene is profoundly positive, usually in the range +300 per thousand to +500 per thousand. Synthetic routes leading to amphetamine, methylamphetamine or their precursors and commencing with such benzaldehyde may be expected to exhibit unusually positive delta(2)H values. Results are presented for delta(13)C and delta(2)H isotope values of 1-phenyl-2-nitropropene synthesized from an industrial source of benzaldehyde, having a positive delta(2)H isotope value, by a Knoevenagel condensation with nitroethane. Results are also presented for delta(13)C and delta(2)H isotope values for amphetamine prepared from the resulting 1-phenyl-2-nitropropene. The values obtained were compared with delta(13)C and delta(2)H isotope values obtained for an amphetamine sample prepared using a synthetic route that did not involve benzaldehyde. Finally, results are presented for samples of benzaldehyde, 1-phenyl-2-nitropropene and amphetamine that had been seized at a clandestine amphetamine laboratory.

  12. GRAFTED STYRENE-DIVINYLBENZENE COPOLYMERS CONTAINING BENZALDEHYDES AND THEIR WITTIG REACTIONS WITH VARIOUS PHOSPHONIUM SALTS

    Institute of Scientific and Technical Information of China (English)

    Adriana Popa; Gheorghe Ilia; Aurelia Pascariu; Smaranda Iliescu; Nicoleta Plesu

    2005-01-01

    A chloromethylated styrene-divinylbenzene copolymer support system functionalized with 4-benzaldehyde and 2-benzaldehyde was prepared. The degree of functionalization with aldehyde groups is well suited for the subsequent use of the products as Wittig reagents. The polymer bound aldehyde was reacted with Wittig reagents to give olefin groups grafted on styrene-divinylbenzene copolymers. The reactions were carried out in phase transfer catalysis conditions. A simple procedure for the calculation of the degree of functionalization and the statistical modeling of the structural repetitive unit of the copolymer are reported.

  13. Benzaldehyde in cherry flavour as a precursor of benzene formation in beverages.

    Science.gov (United States)

    Loch, Christine; Reusch, Helmut; Ruge, Ingrid; Godelmann, Rolf; Pflaum, Tabea; Kuballa, Thomas; Schumacher, Sandra; Lachenmeier, Dirk W

    2016-09-01

    During sampling and analysis of alcohol-free beverages for food control purposes, a comparably high contamination of benzene (up to 4.6μg/L) has been detected in cherry-flavoured products, even when they were not preserved using benzoic acid (which is a known precursor of benzene formation). There has been some speculation in the literature that formation may occur from benzaldehyde, which is contained in natural and artificial cherry flavours. In this study, model experiments were able to confirm that benzaldehyde does indeed degrade to benzene under heating conditions, and especially in the presence of ascorbic acid. Analysis of a large collective of authentic beverages from the market (n=170) further confirmed that benzene content is significantly correlated to the presence of benzaldehyde (r=0.61, pbenzaldehyde in combination with ascorbic acid should be avoided.

  14. Antifungal activity of redox-active benzaldehydes that target cellular antioxidation

    Directory of Open Access Journals (Sweden)

    Mahoney Noreen

    2011-05-01

    Full Text Available Abstract Background Disruption of cellular antioxidation systems should be an effective method for control of fungal pathogens. Such disruption can be achieved with redox-active compounds. Natural phenolic compounds can serve as potent redox cyclers that inhibit microbial growth through destabilization of cellular redox homeostasis and/or antioxidation systems. The aim of this study was to identify benzaldehydes that disrupt the fungal antioxidation system. These compounds could then function as chemosensitizing agents in concert with conventional drugs or fungicides to improve antifungal efficacy. Methods Benzaldehydes were tested as natural antifungal agents against strains of Aspergillus fumigatus, A. flavus, A. terreus and Penicillium expansum, fungi that are causative agents of human invasive aspergillosis and/or are mycotoxigenic. The yeast Saccharomyces cerevisiae was also used as a model system for identifying gene targets of benzaldehydes. The efficacy of screened compounds as effective chemosensitizers or as antifungal agents in formulations was tested with methods outlined by the Clinical Laboratory Standards Institute (CLSI. Results Several benzaldehydes are identified having potent antifungal activity. Structure-activity analysis reveals that antifungal activity increases by the presence of an ortho-hydroxyl group in the aromatic ring. Use of deletion mutants in the oxidative stress-response pathway of S. cerevisiae (sod1Δ, sod2Δ, glr1Δ and two mitogen-activated protein kinase (MAPK mutants of A. fumigatus (sakAΔ, mpkCΔ, indicates antifungal activity of the benzaldehydes is through disruption of cellular antioxidation. Certain benzaldehydes, in combination with phenylpyrroles, overcome tolerance of A. fumigatus MAPK mutants to this agent and/or increase sensitivity of fungal pathogens to mitochondrial respiration inhibitory agents. Synergistic chemosensitization greatly lowers minimum inhibitory (MIC or fungicidal (MFC

  15. Oscillatory oxidation of benzaldehyde by air. 1. Experimental observations

    Energy Technology Data Exchange (ETDEWEB)

    Colussi, A.J.; Ghibaudi, E.; Yuan, Zhi; Noyes, R.M. (Univ. of Oregon, Eugene (USA))

    1990-11-21

    In 90% aqueous acetic acid at 70 C, the oxidation of benzaldehyde to benzoic acid by air is catalyzed by a mixture of cobalt(II) and bromide. Jensen has shown that the concentration of cobalt(III) undergoes major oscillations during the reaction. Consistent with these prior observations, the authors find that the rate of formation of cobalt(III) increases exponentially until at about 10{sup {minus}5} M s{sup {minus}1} it becomes comparable to the maximum rate at which O{sub 2} can be transported from atmosphere to solution. A virtually discontinuous change of behavior then causes the concentration of cobalt(III) to decrease at about 10{sup {minus}4} M s{sup {minus}1}; the rate of this decrease is almost constant and independent of (Co{sup III}) until most of this species has been consumed. The authors have examined most of the subsystems that they could prepare and study independently. Among other observations, they find that increasing acidity increases the rate at which bromide catalyzes the oxidation of benzaldehyde by cobalt(III).

  16. Reactions of supercritical water and supercritical methanol with benzaldehyde; Chorinkaisui oyobi chorinkai methanol to benzaldehyde tono hanno

    Energy Technology Data Exchange (ETDEWEB)

    Yokoyama, C.; Yasuda, T.; Nishi, K.; Takahashi, S. [Tohoku University, Sendai (Japan). Institute for Chemical Reaction Science

    1996-11-01

    The reactions of supercritical water and supercritical methanol with benzaldehyde have been examined in the temperature range from 553 to 693 K, and the reaction pathways have been examined from the temporal variations of the reaction products. For the reaction of benzaldehyde with supercritical water, the major product was benzene, which was formed from the pyrolysis of benzaldehyde. The benzoic acid and benzyl alcohol were the by-products, produced from the Cannizzaro-type disproportionation reaction of benzaldehyde with the hydrate formed from the reaction with water and benzaldehyde. The major product for the reaction of benzaldehyde with supercritical methanol was benzyl alcohol, and the by-product were dimethylacetal, benzene, and methyl benzoic acid. Under the reaction conditions of this study, a significant amount of acetal was produced from benzaldehyde and methanol. The pyrolysis of acetal yielded benzyl alcohol. 29 refs., 6 figs., 4 tabs.

  17. Large-scale synthesis of ultrathin tungsten oxide nanowire networks: an efficient catalyst for aerobic oxidation of toluene to benzaldehyde under visible light.

    Science.gov (United States)

    Bai, Hua; Yi, Wencai; Liu, Jingyao; Lv, Qing; Zhang, Qing; Ma, Qiang; Yang, Haifeng; Xi, Guangcheng

    2016-07-14

    As a very important chemical raw material, the selective formation of benzaldehyde from toluene at preparative or industrial levels requires the use of highly corrosive chlorine and high reaction temperatures, which severely corrodes equipment, pollutes the environment, and consumes a lot of energy. Herein, we report a robust and highly active catalyst for the benzaldehyde evolution reaction that is constructed by the surfactant-free growth of oxygen vacancy-rich W18O49 ultrathin nanowire networks. Under atmospheric pressure and visible-light irradiation, the new catalyst can selectively (92% selectivity) catalyze the aerobic oxidation of toluene to benzaldehyde with yields of above 95%.

  18. Preparation, characterization and catalytic activity of CoFe2O4 nanoparticles as a magnetically recoverable catalyst for selective oxidation of benzyl alcohol to benzaldehyde and reduction of organic dyes.

    Science.gov (United States)

    Nasrollahzadeh, Mahmoud; Bagherzadeh, Mojtaba; Karimi, Hirbod

    2016-03-01

    The CoFe2O4 nanoparticles (NPs) performance was studied in the oxidation of benzyl alcohol (BzOH) to benzaldehyde (BzH) with hydrogen peroxide as an oxidant under solvent-free conditions. The influences of reaction conditions like the amount of catalyst, the molar ratio of H2O2:BzOH, reaction temperature and times on the oxidation of BzOH by using CoFe2O4 NPs were investigated in details. Under optimum conditions, excellent result, >99% conversation of BzOH to BzH as the only product, was obtained. The nanocatalyst was also used for the reduction of 4-nitrophenol (4-NP), Congo red (CR), Methylene blue (MB) in water at room temperature. The magnetic properties of the catalyst provided a convenient and easy route for the separation of the catalyst from the reaction mixture by an external bar magnet. No obvious loss of activity was observed when the spent catalyst reused in three consecutive runs.

  19. Photoelectrochemical detection of benzaldehyde in foodstuffs

    Energy Technology Data Exchange (ETDEWEB)

    LaCourse, W.R.; Krull, I.S.

    1987-01-01

    Photoelectrochemical detection (PED) coupled with high performance liquid chromatography was used to quantitatively determine benzaldehyde in extracts, beverages, and foodstuffs. Photoelectrochemical detection is responsive to alkyl and aryl ketones and aldehydes and offers the advantages of 2-3 orders of magnitude linearity, 5-1-ng limits of detection, and a high degree of selectivity without chemical derivatization. This is the first application of the PED to sample analysis.

  20. Preparation of natural brucite nanofibers by the dispersion method

    Institute of Scientific and Technical Information of China (English)

    Li Xu; Wen Ni; Wenping Li; Xingde Liu; Hailong Yang; Xiaoguang Yang

    2008-01-01

    The preparation of natural brucite nanofibers through dispersion by the wet process is described. The test results indicate that brucite fibers can be well dispersed by using sodium dioctyl sulfosuccinate (OT) as the dispersant at a dispersant/fiber mass ratio of 0.15:1, dispersing for 30 min at a water/solid mass ratio of 20:1. The prepared nanofibers were characterized with X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM). It is shown that the prepared single brucite nanofiber is around 30 run in diameter and the talus of the nonsingle brucite nanofibers is about 50-150 nm in diameter. Natural brucite mineral fibers were treated by the dispersion method to obtain nanomaterials. These fibers have significant advantages over artificial nanofibers both in yield and in cost.

  1. Preparation and antimicrobial ability of natural porous antibacterial materials

    Institute of Scientific and Technical Information of China (English)

    DONG Fa-qin; LI Guo-wu; SUN Zhi-gang; SHEN Gang; FENG Qi-ming; DAI Qun-wei

    2005-01-01

    The liquid ion exchange method, solid salt melt method and dry-wet circulation method were used to prepare natural porous antimicrobial materials with natural minerals, such as zeolite, spilite, palygorskite and montmorillonite, respectively. Atomic absorption spectrum and X-ray diffraction analysis were carried out to investigate the effects of Ag+, Cu2+ and Zn2+ on antimicrobial abilities of natural porous minerals, and the effect of preparation method on ion exchange capacity of antimicrobial material, respectively. The results show that for the ion exchange capacity, clay mineral is higher than fibrous mineral, i.e. both zeolite and montmorillonite are higher; the antimicrobial ability of material with Ag+ is the best; the exchange capacities of materials with Cu2+ or Zn2+ are all higher, but the antimicrobial ability of Cu2+ is better than that of Zn2+.

  2. Synthesis of mutagenic 2,4-dinitro-[7-[sup 14]C]benzaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Shoji, Miki; Kozuka, Hiroshi; Honda, Takashi (Toyama Medical and Pharmaceutical Univ. (Japan)); Mori, Masaaki (Kyushu Univ., Fukuoka (Japan). School of Health Sciences); Sayama, Michio (Toyama Univ. (Japan))

    1994-07-01

    2,4-Dinitro-[7-[sup 14]C]benzaldehyde (4), a mutagenic substance which may have unique metabolic activating pathways, was synthesized as a tracer for the detection of adducts of 4 with macromolecules. The preparation was performed in four steps from [7-[sup 14]C]toluene to give an overall radiochemical yield of 20% after purifying by TLC. The radiochemical purity was over 98%. (Author).

  3. Large-scale synthesis of ultrathin tungsten oxide nanowire networks: an efficient catalyst for aerobic oxidation of toluene to benzaldehyde under visible light

    Science.gov (United States)

    Bai, Hua; Yi, Wencai; Liu, Jingyao; Lv, Qing; Zhang, Qing; Ma, Qiang; Yang, Haifeng; Xi, Guangcheng

    2016-07-01

    As a very important chemical raw material, the selective formation of benzaldehyde from toluene at preparative or industrial levels requires the use of highly corrosive chlorine and high reaction temperatures, which severely corrodes equipment, pollutes the environment, and consumes a lot of energy. Herein, we report a robust and highly active catalyst for the benzaldehyde evolution reaction that is constructed by the surfactant-free growth of oxygen vacancy-rich W18O49 ultrathin nanowire networks. Under atmospheric pressure and visible-light irradiation, the new catalyst can selectively (92% selectivity) catalyze the aerobic oxidation of toluene to benzaldehyde with yields of above 95%.As a very important chemical raw material, the selective formation of benzaldehyde from toluene at preparative or industrial levels requires the use of highly corrosive chlorine and high reaction temperatures, which severely corrodes equipment, pollutes the environment, and consumes a lot of energy. Herein, we report a robust and highly active catalyst for the benzaldehyde evolution reaction that is constructed by the surfactant-free growth of oxygen vacancy-rich W18O49 ultrathin nanowire networks. Under atmospheric pressure and visible-light irradiation, the new catalyst can selectively (92% selectivity) catalyze the aerobic oxidation of toluene to benzaldehyde with yields of above 95%. Electronic supplementary information (ESI) available: Experimental procedure, XRD patterns, TEM and HRTEM images, energy-dispersive X-ray spectra, UV-vis spectra, X-ray photoelectron spectroscopy (XPS), and EDS. See DOI: 10.1039/c6nr02949c

  4. Direct Spectrophotometric Assay for Benzaldehyde Lyase Activity

    Directory of Open Access Journals (Sweden)

    Dessy Natalia

    2011-01-01

    Full Text Available Benzaldehyde lyase from Pseudomonas fluorescens Biovar I. (BAL, EC 4.1.2.38 is a versatile catalyst for the organic synthesis of chiral α-hydroxy ketones. To allow fast assessment of enzyme activity, a direct spectrophotometric assay is desirable. Here, a new robust and easy-to-handle assay based on UV absorption is presented. The assay developed is based on the ligation of the α-hydroxy ketone (R-2,2′-furoin from 2-furaldehyde. A robust assay with direct monitoring of the product is facilitated with a convenient concentration working range minimising experimental associated with low concentrations.

  5. Adsorption, mobility, and dimerization of benzaldehyde on Pt(111)

    DEFF Research Database (Denmark)

    Rasmussen, Anton Michael Havelund; Hammer, Bjørk

    2012-01-01

    Building on results for the adsorption of benzene on Pt(111), the adsorption of benzaldehyde is investigated using density functional theory. Benzaldehyde is found to chemisorb preferentially with its aromatic ring in the flat-lying bridge geometry that is also preferred for benzene. Across the i...

  6. Amorphous metal-aluminophosphate catalysts for aldol condensation of n-heptanal and benzaldehyde to jasminaldehyde

    Institute of Scientific and Technical Information of China (English)

    A. Hamza; N. Nagaraju

    2015-01-01

    Amorphous aluminophosphate (AlP) and metal‐aluminophosphates (MAlPs, where M=2.5 mol%Cu, Zn, Cr, Fe, Ce, or Zr) were prepared by coprecipitation method. Their surface properties and catalytic activity for the synthesis of jasminaldehyde through the aldol condensation of n‐heptanal and benzaldehyde were investigated. The nitrogen adsorption‐desorption isotherms showed that the microporosity exhibited by the aluminophosphate was changed to a mesoporous and macroporous structure which depended on the metal incorporated, with a concomitant change in the surface area. Temperature‐programmed desorption of NH3 and CO2 revealed that the materials possessed both acidic and basic sites. The acidic strength of the material was either increased or decreased depending on the nature of the metal. The basicity was increased compared to AlP. All the materials were X‐ray amorphous and powder X‐ray diffraction studies indicated the absence of metal oxide phases. The Fourier transform infrared analysis confirmed the presence of phosphate groups and also the absence of any M‐O moieties in the materials. The selected organic reaction occurred only in the presence of the AlP and MAlPs. The selectivity for the jasminaldehyde product was up to 75%with a yield of 65%. The best conversion of n‐heptanal with a high selectivity to jasminaldehyde was obtained with FeAlP as the catalyst, and this material was characterized to have less weak acid sites and more basic sites.

  7. Benzaldehyde suppresses murine allergic asthma and rhinitis.

    Science.gov (United States)

    Jang, Tae Young; Park, Chang-Shin; Kim, Kyu-Sung; Heo, Min-Jeong; Kim, Young Hyo

    2014-10-01

    To evaluate the antiallergic effects of oral benzaldehyde in a murine model of allergic asthma and rhinitis, we divided 20 female BALB/c mice aged 8-10 weeks into nonallergic (intraperitoneally sensitized and intranasally challenged to normal saline), allergic (intraperitoneally sensitized and intranasally challenged to ovalbumin), and 200- and 400-mg/kg benzaldehyde (allergic but treated) groups. The number of nose-scratching events in 10 min, levels of total and ovalbumin-specific IgE in serum, differential counts of inflammatory cells in bronchoalveolar lavage (BAL) fluid, titers of Th2 cytokines (IL-4, IL-5, IL-13) in BAL fluid, histopathologic findings of lung and nasal tissues, and expressions of proteins involved in apoptosis (Bcl-2, Bax, caspase-3), inflammation (COX-2), antioxidation (extracellular SOD, HO-1), and hypoxia (HIF-1α, VEGF) in lung tissue were evaluated. The treated mice had significantly fewer nose-scratching events, less inflammatory cell infiltration in lung and nasal tissues, and lower HIF-1α and VEGF expressions in lung tissue than the allergic group. The number of eosinophils and neutrophils and Th2 cytokine titers in BAL fluid significantly decreased after the treatment (Pbenzaldehyde exerts antiallergic effects in murine allergic asthma and rhinitis, possibly through inhibition of HIF-1α and VEGF.

  8. Oxidation of benzyl alcohol by K2FeO4 to benzaldehyde over zeolites

    Science.gov (United States)

    Wang, Yuan-Yuan; Song, Hua; Song, Hua-Lin; Jin, Zai-Shun

    2016-10-01

    A novel and green procedure for benzaldehyde synthesis by potassium ferrate oxidation of benzyl alcohol employing zeolite catalysts was studied. The prepared oxidant was characterized by SEM and XRD. The catalytic activity of various solid catalysts was studied using benzyl alcohol as a model compound. USY was found to be a very efficient catalyst for this particular oxidation process. Benzaldehyde yields up to 96.0% could be obtained at the following optimal conditions: 0.2 mL of benzyl alcohol, 4 mmol of K2FeO4, 0.5 g of USY zeolite; 20 mL of cyclohexene, 0.3 mL of acetic acid (36 wt %), 30°C temperature, 4 h reaction time.

  9. Preparation of natural isovaleraldehyde by the Maillard reaction

    Institute of Scientific and Technical Information of China (English)

    Hong Yu Tian; Jie Zhang; Bao Guo Sun; Ming Quan Huang; Jian Rong Li; Xiao Xiang Han

    2007-01-01

    Isovaleraldehyde possesses malty, fruity, cocoa-like odor and is widely used in fruit, chocolate, coffee flavors. The preparation of natural isovaleraldehyde by the Maillard model reaction was studied in this paper. The effects of the ratio of D-glucose/L-leucine,reaction temperature and pH value on the yield of isovaleraldehyde were explored. The optimum conditions were as follows:n(D-glucose):n(L-leucine) = 4, temperature 150 ℃, reaction time 3 h, pH 5. The highest yield of isovaleraldehyde obtained was about 32%.

  10. Removal of benzaldehyde from a water/ethanol mixture by applying scavenging techniques

    DEFF Research Database (Denmark)

    Mitic, Aleksandar; Skov, Thomas; Gernaey, Krist V.

    2017-01-01

    derivatization agents as the scavengers. Discovery chemistry is performed in the beginning as a screening procedure, followed by the process design of a small-scale continuous process for benzaldehyde removal with in-line real-time monitoring. Applications of tris(hydroxymethyl) aminomethane (TRIS) are found......A presence of carbonyl compounds is very common in the food industry. The nature of such compounds is to be reactive and thus many products involve aldehydes/ketones in their synthetic routes. By contrast, the high reactivity of carbonyl compounds could also lead to formation of undesired compounds......, such as genotoxic impurities. It can therefore be important to remove carbonyl compounds by implementing suitable removal techniques, with the aim of protecting final product quality. This work is focused on benzaldehyde as a model component, studying its removal from a water/ethanol mixture by applying different...

  11. Benzaldehyde dehydrogenase from chitosan-treated Sorbus aucuparia cell cultures.

    Science.gov (United States)

    Gaid, Mariam M; Sircar, Debabrata; Beuerle, Till; Mitra, Adinpunya; Beerhues, Ludger

    2009-09-01

    Cell cultures of Sorbus aucuparia respond to the addition of chitosan with the accumulation of the biphenyl phytoalexin aucuparin. The carbon skeleton of this inducible defense compound is formed by biphenyl synthase (BIS) from benzoyl-CoA and three molecules of malonyl-CoA. The formation of benzoyl-CoA proceeds via benzaldehyde as an intermediate. Benzaldehyde dehydrogenase (BD), which converts benzaldehyde into benzoic acid, was detected in cell-free extracts from S. aucuparia cell cultures. BD and BIS were induced by chitosan treatment. The preferred substrate for BD was benzaldehyde (K(m)=49 microM). Cinnamaldehyde and various hydroxybenzaldehydes were relatively poor substrates. BD activity was strictly dependent on the presence of NAD(+) as a cofactor (K(m)=67 microM).

  12. The determination of furaldehyde and benzaldehyde in plum brandy

    Directory of Open Access Journals (Sweden)

    Rajković Miloš B.

    2005-01-01

    Full Text Available Among all alcohol liqueurs, brandies from drupaceous plants are characterized with the highest level of hydro cyanic acid, benzaldehyde and ethylcarbamate. In fruit brandies ethylcarbamate mainly originates from hydro cyanic acid during the processes of alcohol fermentation of crushed fruit and its preservation, distillation and ripening of the brandy. Hydro cyanic acid and benzaldehyde arise from the hydrolysis of amygdaline that is found exist in the heart of fruit stones and seeds, as well as from the hydrolysis of prunasine from the skin and flesh of drupaceous plants. The content of amygdaline and prunazine depends on the type of fruit, which corresponds to the potential content of hydro cyanic acid and benzaldehyde in the brandy that corresponds the stoichiometric ratio 1:3.94. The content of the aldehydes: furfural and benzaldehyde in plum brandy, strong plum brandy, young brandy, of domestic production in the various regions of Serbia were analyzed in this paper.

  13. Involvement of snapdragon benzaldehyde dehydrogenase in benzoic acid biosynthesis.

    Science.gov (United States)

    Long, Michael C; Nagegowda, Dinesh A; Kaminaga, Yasuhisa; Ho, Kwok Ki; Kish, Christine M; Schnepp, Jennifer; Sherman, Debra; Weiner, Henry; Rhodes, David; Dudareva, Natalia

    2009-07-01

    Benzoic acid (BA) is an important building block in a wide spectrum of compounds varying from primary metabolites to secondary products. Benzoic acid biosynthesis from L-phenylalanine requires shortening of the propyl side chain by two carbons, which can occur via a beta-oxidative pathway or a non-beta-oxidative pathway, with benzaldehyde as a key intermediate. The non-beta-oxidative route requires benzaldehyde dehydrogenase (BALDH) to convert benzaldehyde to BA. Using a functional genomic approach, we identified an Antirrhinum majus (snapdragon) BALDH, which exhibits 40% identity to bacterial BALDH. Transcript profiling, biochemical characterization of the purified recombinant protein, molecular homology modeling, in vivo stable isotope labeling, and transient expression in petunia flowers reveal that BALDH is capable of oxidizing benzaldehyde to BA in vivo. GFP localization and immunogold labeling studies show that this biochemical step occurs in the mitochondria, raising a question about the role of subcellular compartmentalization in BA biosynthesis.

  14. Fluorescence Quenching of Benzaldehyde in Water by Hydrogen Atom Abstraction.

    Science.gov (United States)

    Fletcher, Katharyn; Bunz, Uwe H F; Dreuw, Andreas

    2016-09-01

    We computed the mechanism of fluorescence quenching of benzaldehyde in water through relaxed potential energy surface scans. Time-dependent density functional theory calculations along the protonation coordinate from water to benzaldehyde reveal that photoexcitation to the bright ππ* (S3 ) state is immediately followed by ultrafast decay to the nπ* (S1 ) state. Evolving along this state, benzaldehyde (BA) abstracts a hydrogen atom, resulting in a BAH(.) and OH(.) radical pair. Benzaldehyde does not act as photobase in water, but abstracts a hydrogen atom from a nearby solvent molecule. The system finally decays back to the ground state by non-radiative decay and an electron transfers back to the OH(.) radical. Proton transfer from BAH(+) to OH(-) restores the initial situation, BA in water.

  15. 磺酸化介孔二氧化硅的合成及催化苯甲醛和乙二醇的加成反应%Preparation of sulfo-functionlized mesoporous silica and its catalytic performance in addition of benzaldehyde and ethylene glycol

    Institute of Scientific and Technical Information of China (English)

    胡建; 夏成波; 彭静; 郑净植

    2011-01-01

    以CTAB为模板剂,通过溶胶-凝胶法制备了介孔二氧化硅,将聚(苯乙烯-二乙烯苯)包覆在介孔二氧化硅表面,并进行磺酸化制备了一种新型的固体酸催化剂;通过FT-IR、TGA、TEM等表征方法对合成的磺酸化介孔二氧化硅进行了表征.结果表明:表面聚合物基团和磺酸根基团成功地引入到了二氧化硅表面,磺酸化的介孔二氧化硅具有较好的孔道有序结构.磺酸化介孔二氧化硅对苯甲醛和乙二醇的加成反应表现出了较高的酸催化性能.%The mesoporous silica was synthesized by sol-gel method using CTAB as template, and then a novel ordered mesoporous solid acid catalyst was prepared by sulfonation of polymers coating on surface of mesoporous silica.The samples were characterized by FT-IR, TGA and TEM.The results indicated that the meso-structure of the sample was retained, and the polymer groups and -SO3H groups had been successfully incorporated on the surface of silica.The sample show high catalytic performance toward the addition reaction of benzaldehyde and ethylene glycol.

  16. Preparation of metagenomic libraries from naturally occurring marine viruses.

    Science.gov (United States)

    Solonenko, Sergei A; Sullivan, Matthew B

    2013-01-01

    Microbes are now well recognized as major drivers of the biogeochemical cycling that fuels the Earth, and their viruses (phages) are known to be abundant and important in microbial mortality, horizontal gene transfer, and modulating microbial metabolic output. Investigation of environmental phages has been frustrated by an inability to culture the vast majority of naturally occurring diversity coupled with the lack of robust, quantitative, culture-independent methods for studying this uncultured majority. However, for double-stranded DNA phages, a quantitative viral metagenomic sample-to-sequence workflow now exists. Here, we review these advances with special emphasis on the technical details of preparing DNA sequencing libraries for metagenomic sequencing from environmentally relevant low-input DNA samples. Library preparation steps broadly involve manipulating the sample DNA by fragmentation, end repair and adaptor ligation, size fractionation, and amplification. One critical area of future research and development is parallel advances for alternate nucleic acid types such as single-stranded DNA and RNA viruses that are also abundant in nature. Combinations of recent advances in fragmentation (e.g., acoustic shearing and tagmentation), ligation reactions (adaptor-to-template ratio reference table availability), size fractionation (non-gel-sizing), and amplification (linear amplification for deep sequencing and linker amplification protocols) enhance our ability to generate quantitatively representative metagenomic datasets from low-input DNA samples. Such datasets are already providing new insights into the role of viruses in marine systems and will continue to do so as new environments are explored and synergies and paradigms emerge from large-scale comparative analyses.

  17. High efficient photocatalytic selective oxidation of benzyl alcohol to benzaldehyde by solvothermal-synthesized ZnIn{sub 2}S{sub 4} microspheres under visible light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zhixin, E-mail: czx@fzu.edu.cn [State Key Laboratory Breeding Base of Photocatalysis, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350002 (China); Instrumental Measurement and Analysis Center, Fuzhou University, Fuzhou 350002 (China); Xu, Jingjing; Ren, Zhuyun [State Key Laboratory Breeding Base of Photocatalysis, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350002 (China); He, Yunhui; Xiao, Guangcan [State Key Laboratory Breeding Base of Photocatalysis, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350002 (China); Instrumental Measurement and Analysis Center, Fuzhou University, Fuzhou 350002 (China)

    2013-09-15

    Hexagonal ZnIn{sub 2}S{sub 4} samples have been synthesized by a solvothermal method. Their properties have been determined by X-ray diffraction, ultraviolet–visible-light diffuse reflectance spectra, field emission scanning electron microscopy, nitrogen adsorption–desorption and X-ray photoelectron spectra. These results demonstrate that ethanol solvent has significant influence on the morphology, optical and electronic nature for such marigold-like ZnIn{sub 2}S{sub 4} microspheres. The visible light photocatalytic activities of the ZnIn{sub 2}S{sub 4} have been evaluated by selective oxidation of benzyl alcohol to benzaldehyde using molecular oxygen as oxidant. The results show that 100% conversion along with >99% selectivity are reached over ZnIn{sub 2}S{sub 4} prepared in ethanol solvent under visible light irradiation (λ>420 nm) of 2 h, but only 58% conversion and 57% yield are reached over ZnIn{sub 2}S{sub 4} prepared in aqueous solvent. A possible mechanism of the high photocatalytic activity for selective oxidation of benzyl alcohol over ZnIn{sub 2}S{sub 4} is proposed and discussed. - Graphical abstract: Marigold-like ZnIn{sub 2}S{sub 4} microspheres were synthesized by a solvothermal method. The high visible photocatalytic activities of ZnIn{sub 2}S{sub 4} were evaluated by selective oxidation of benzyl alcohol to benzaldehyde under mild conditions. Display Omitted - Highlights: • Marigold-like ZnIn{sub 2}S{sub 4} microspheres were synthesized by a solvothermal method. • The solvents have a remarkably influence on the morphology and properties of samples. • It is the first time to apply ZnIn{sub 2}S{sub 4} for selective oxidation of benzyl alcohol. • ZnIn{sub 2}S{sub 4} shows high photocatalytic activity for selective oxidation of benzyl alcohol.

  18. Toxic element contamination of natural health products and pharmaceutical preparations.

    Directory of Open Access Journals (Sweden)

    Stephen J Genuis

    Full Text Available BACKGROUND: Concern has recently emerged regarding the safety of natural health products (NHPs-therapies that are increasingly recommended by various health providers, including conventional physicians. Recognizing that most individuals in the Western world now consume vitamins and many take herbal agents, this study endeavored to determine levels of toxic element contamination within a range of NHPs. METHODS: Toxic element testing was performed on 121 NHPs (including Ayurvedic, traditional Chinese, and various marine-source products as well as 49 routinely prescribed pharmaceutical preparations. Testing was also performed on several batches of one prenatal supplement, with multiple samples tested within each batch. Results were compared to existing toxicant regulatory limits. RESULTS: Toxic element contamination was found in many supplements and pharmaceuticals; levels exceeding established limits were only found in a small percentage of the NHPs tested and none of the drugs tested. Some NHPs demonstrated contamination levels above preferred daily endpoints for mercury, cadmium, lead, arsenic or aluminum. NHPs manufactured in China generally had higher levels of mercury and aluminum. CONCLUSIONS: Exposure to toxic elements is occurring regularly as a result of some contaminated NHPs. Best practices for quality control-developed and implemented by the NHP industry with government oversight-is recommended to guard the safety of unsuspecting consumers.

  19. O-季铵化-N-(4-十二烷氧基)壳聚糖苯甲醛席夫碱的制备及胶束pH响应性%Preparation and micelle pH response ofO-quaternary ammonium-N-(4-dodecyloxy) chitosan benzaldehyde Schiff’s bass

    Institute of Scientific and Technical Information of China (English)

    林意华; 李明春; 辛梅华; 陈燕燕

    2015-01-01

    制备双亲性的O-季铵化-N-(4-十二烷氧基)壳聚糖苯甲醛席夫碱(QA-CS-DBA),采用FTIR、1H NMR及元素分析对产物进行表征。通过超声法制备QA-CS-DBA载酮洛芬胶束,考察胶束的临界胶束浓度、粒径、Zeta电位、载药量和包封率,并对胶束在不同 pH 值条件下的药物释放行为及 Zeta 电位变化进行研究。结果表明, QA-CS-DBA能将酮洛芬包载于胶束疏水内核,载药量为39.37%,包封率为46.04%,载药胶束粒径为341nm, Zeta电位为30.8mV。胶束Zeta电位及载药胶束的药物释放行为具有pH响应性。%AmphiphilicO-quaternary ammonium-N-(4-dodecyloxy) chitosan benzaldehyde Schiff’s base (QA-CS- DBA) was prepared. FTIR,1H NMR and EA were used to confirm its structure. The micelle of QA-CS-DBA carrying ketoprofen was made by ultrasounding. The CMC,size,Zeta potential,drug loading capacity and encapsulation efficiency were studied,especially the behavior of drug release and the change of Zeta potential in different PBS buffer solution with different pH. The result shows that QA-CS-DBA could form stable drug loading micelles carrying ketoprofen with the size about 341nm. The drug loading capacity and the encapsulation efficiency are 39.37% and 46.04% respectively and the Zeta potential is 30.8mV. With pH changing between 7.40 and 6.50,the micelle shows different Zeta potentials and different behaviors in drug release.

  20. Adsorption of Benzaldehyde on Granular Activated Carbon: Kinetics, Equilibrium, and Thermodynamic

    OpenAIRE

    Rajoriya, R.K.; Prasad, B; Mishra, I.M.; Wasewar, K. L.

    2007-01-01

    Adsorption isotherms of benzaldehyde from aqueous solutions onto granular activated carbon have been determined and studied the effect of dosage of granular activated carbon, contact time, and temperature on adsorption. Optimum conditions for benzaldehyde removal were found adsorbent dose 4 g l–1 of solution and equilibrium time t 4 h. Percent removal of benzaldehyde increases with the increase in adsorbent dose for activated carbon, however, it decreases with increase in benzaldehyde m...

  1. Calorimetric study of benzaldehyde interaction with acetic anhydride

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, A.M.; Ivanova, L.A.

    1978-03-01

    Benzaldehyde conversion to benzylidene diacetate, a side reaction reducing the selectivity of benzaldehyde oxidation to acetylbenzoyl peroxide, studied at 6/sup 0/-50/sup 0/C, was an irreversible third-order reaction catalyzed by beryllium sulfate or by succinnic, chloroacetic, and particularly sulfuric and perchloric acids. In the presence of organic solvents, (e.g., benzene, hexane, or cyclohexane), the process was complicated by acidolysis and parallel C-acylation reactions, and the catalyst rapidly deactivated. A microcalorimetric method was developed to determine kinetic parameters of the process in the absence of the solvents. Tables and graphs.

  2. Enzymatic (R)-phenylacetylcarbinol production in benzaldehyde emulsions.

    Science.gov (United States)

    Rosche, B; Leksawasdi, N; Sandford, V; Breuer, M; Hauer, B; Rogers, P

    2002-10-01

    (R)-Phenylacetylcarbinol [(R)-PAC)] is the chiral precursor for the production of the pharmaceuticals ephedrine and pseudoephedrine. Reaction conditions were improved to achieve increased (R)-PAC levels in a simple batch biotransformation of benzaldehyde emulsions and pyruvate, using partially purified pyruvate decarboxylase (PDC) from the filamentous fungus Rhizopus javanicus NRRL 13161 as the catalyst. Lowering the temperature from 23 degrees C to 6 degrees C decreased initial rates but increased final (R)-PAC concentrations. Addition of ethanol, which increases benzaldehyde solubility, was not beneficial for (R)-PAC production. It was established that proton uptake during biotransformation increases the pH above 7 thereby limiting (R)-PAC production. For small-scale studies, biotransformations were buffered with 2-2.5 M MOPS (initial pH 6.5). High concentrations of MOPS as well as some alcohols and KCl stabilised PDC. A balance between PDC and substrate concentrations was determined with regards to ( R)-PAC production and yields on enzyme and substrates. R. javanicus PDC (7.4 U/ml) produced 50.6 g/l (337 mM) ( R)-PAC in 29 h at 6 degrees C with initial 400 mM benzaldehyde and 600 mM pyruvate. Molar yields on consumed benzaldehyde and pyruvate were 97% and 59%, respectively, with 17% pyruvate degraded and 24% converted into acetaldehyde and acetoin; 43% PDC activity remained, indicating reasonable enzyme stability at high substrate and product concentrations.

  3. Biocidal polymers: synthesis and antimicrobial properties of benzaldehyde derivatives immobilized onto amine-terminated polyacrylonitrile

    Directory of Open Access Journals (Sweden)

    Alamri Abdullah

    2012-10-01

    Full Text Available Abstract Background The design and applications of antimicrobial polymers is a growing field. Antimicrobial polymers can help to solve the problems associated with the use of conventional antimicrobial agents. Polymers with active functional groups can act as a carrier system for antimicrobial agents. In our study, we aim to prepare and develop some antimicrobial polymers for biomedical applications and water treatment. Results The antimicrobial polymers based on polyacrylonitrile (PAN were prepared. Functional groups were created onto polyacrylonitrile via amination using different types of diamines such as ethylenediamine (EDA and hexamethylenediamine (HMDA to yield amine-terminated polymers. Antimicrobial polymers were obtained by immobilization of benzaldehyde and its derivatives which include, 4-hydroxybenzaldehyde and 2,4-dihydroxybenzaldehyde onto amine-terminated polymers. The antimicrobial activity of the prepared polymers against different types of microorganisms including Gram-positive bacteria (Staphylococcus aureus, Gram-negative bacteria (Pseudomonas aeruginosa; Escherichia coli; and Salmonella typhi as well as fungi (Aspergillus flavus, Aspergillus niger, Candida albicans, Cryptpcoccus neoformans were explored by the cut plug method and viable cell counting methods. Conclusions Amine-terminated polyacrylonitrile were used as a novel polymeric carrier for benzaldehyde derivatives as antimicrobial agents. The prepared polymers can inhibit the growth of the microorganisms. The activity was varied according to the tested microorganism as well as the polymer microstructure. It was found that the activity increased with increasing the number phenolic hydroxyl group of the bioactive group. Finally, it is anticipated that the prepared antimicrobial polymers would be of great help in the field of biomedical applications and biological water treatment.

  4. A Sequential Preparation of Organic Compounds for Senior Chemistry Classes

    Science.gov (United States)

    Merrigan, Cecilia; Crotty, Patricia

    1971-01-01

    Describes procedures suitable for student preparation of benzaldehyde, benzoic acid, and ethyl benzoate sequentially from benzyl alcohol. Preparation for benzyl chloride also given. All reagents except benzyl alcohol are common inorganic chemicals. (AL)

  5. Reduction of benzaldehyde by methoxide ion in aqueous methanol

    Energy Technology Data Exchange (ETDEWEB)

    Swain, C.G.; Powell, A.L.; Lynch, T.J.; Alpha, S.R.; Dunlap, R.P.

    1979-06-20

    In contrast to previous studies of the Cannizzaro reaction using isotopically labeled reactants, the benzyl alcohol from reaction of 0.60 M benzaldehyde-..cap alpha..-d and 0.25 M NaOH in 74% CH/sub 3/OH to 26% H/sub 2/O solution at 100/sup 0/C includes a substantial percentage of benzyl-..cap alpha..-d/sub 1/ alcohol (21% after half consumption of hydroxide ion) rather than only benzyl-..cap alpha..-d/sub 2/ alcohol. Products from C/sub 6/H/sub 5/CHO in CH/sub 3/OH, CH/sub 3/OH solutions indicate that the side reactions responsible for hydrogen exchanges and adding to the yield of benzyl alcohol are (1) bimolecular hydride transfer to benzaldehyde from methoxide ion, (2) a nearly equal amount of crossed Cannizzaro reaction from the resulting formaldehyde, (3) a smaller amount of hydride transfer to benzaldehyde from the resulting sodium formate leading to sodium carbonate, and (4) a less frequent combination of two benzaldehydes plus methoxide ion leading to benzaldehyde dimethyl acetal. Decreasing the initial concentration of C/sub 6/H/sub 5/CHO to 5 x 10/sup -4/ M decreases the relative contributions of the three termolecular reactions and causes the bimolecular hydride transfer (1) to become the dominant reaction. Its k/sub CH/sub 3/O/sup -///k/sub CD/sub 3/O/sup -// isotope effect is 2.2 +- 0.2. 1 table.

  6. Two-dimensional preparative liquid chromatography system for preparative separation of minor amount components from complicated natural products

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Ying-Kun, E-mail: qyk@xmu.edu.cn; Chen, Fang-Fang; Zhang, Ling-Ling; Yan, Xia; Chen, Lin; Fang, Mei-Juan; Wu, Zhen, E-mail: wuzhen@xmu.edu.cn

    2014-04-01

    Highlights: • Preparative MDLC system was developed for separation of complicated natural products. • Medium-pressure LC and preparative HPLC were connected by interface of SPE. • Automated multi-step preparative separation of 25 compounds was achieved by using this system. - Abstract: An on-line comprehensive two-dimensional preparative liquid chromatography system was developed for preparative separation of minor amount components from complicated natural products. Medium-pressure liquid chromatograph (MPLC) was applied as the first dimension and preparative HPLC as the second one, in conjunction with trapping column and makeup pump. The performance of the trapping column was evaluated, in terms of column size, dilution ratio and diameter-height ratio, as well as system pressure from the view of medium pressure liquid chromatograph. Satisfactory trapping efficiency can be achieved using a commercially available 15 mm × 30 mm i.d. ODS pre-column. The instrument operation and the performance of this MPLC × preparative HPLC system were illustrated by gram-scale isolation of crude macro-porous resin enriched water extract of Rheum hotaoense. Automated multi-step preparative separation of 25 compounds, whose structures were identified by MS, {sup 1}H NMR and even by less-sensitive {sup 13}C NMR, could be achieved in a short period of time using this system, exhibiting great advantages in analytical efficiency and sample treatment capacity compared with conventional methods.

  7. Role of catalyst characteristics in electrocatalytic hydrogenation: Reduction of benzaldehyde and acetophenone on carbon felt/Pd electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Polcaro, A.M.; Palmas, S.; Dernini, S. (Univ. di Cagliari, Piazza D' Armi Cagliari (Italy). Dipartimento di Ingegneria Chimica e Materiali)

    1993-07-01

    The hydrogenation of benzaldehyde and acetophenone was investigated at two carbon felt-supported Pd electrocatalysts, prepared by two different methods. The faradaic yield and the selectivity of the reaction were found to be greatly affected by the preparation conditions of the catalyst. A model, based on a reaction electrocatalytic mechanism, involving two parallel steps through which alcohol and hydrocarbon are generated from the reactant adsorbed on different active sites, was performed. The kinetics was described by means of the Langmuir-Hinshelwood rate equations, and the kinetic and equilibrium parameters were determined for both electrocatalysts.

  8. [The modified process for preparing natural organic polymer flocculant chitosan].

    Science.gov (United States)

    Zeng, D; Yu, G; Zhang, P; Feng, Z

    2001-05-01

    The modified process for preparing chitosan from crab or lobster shells was developed. In the decalcification stage, 10% HCl was used as soaking solution with addition of a small quantity of A as a promoter, and the mass ratio of reactants was 10% HCl:A:crab or lobster shells = 3.5:0.5:1, continuously stirring the crab or lobster shells at 30 degrees C for 3 h in place of simply soaking the crab or lobster shells at room temperature for 16-24 h in the previous process. In the deacetylation stage, 40% NaOH solution was used with addition of a small quantity of B as a promoter, and the mass ratio of reactants was 40% NaOH:B:chitin = 4:0.2:1, keeping reaction at 105 degrees C for 2 h in place of at 115 degrees C for 6 h in the previous process. By this new process, the cost of the raw materials used for preparing chitosan was cut down 49%, the preparation time was shortened by one half, and the main properties of this chitosan such as viscosity, deacetylation and molecular weight all approached or exceeded those of the Sigma' commercial chitosan (Chitosan C-3646).

  9. Benzaldehyde is a precursor of phenylpropylamino alkaloids as revealed by targeted metabolic profiling and comparative biochemical analyses in Ephedra spp.

    Science.gov (United States)

    Krizevski, Raz; Bar, Einat; Shalit, O R; Levy, Asaf; Hagel, Jillian M; Kilpatrick, Korey; Marsolais, Frédéric; Facchini, Peter J; Ben-Shabat, Shimon; Sitrit, Yaron; Lewinsohn, Efraim

    2012-09-01

    Ephedrine and pseudoephedrine are phenylpropylamino alkaloids widely used in modern medicine. Some Ephedra species such as E. sinica Stapf (Ephedraceae), a widely used Chinese medicinal plant (Chinese name: Ma Huang), accumulate ephedrine alkaloids as active constituents. Other Ephedra species, such as E. foeminea Forssk. (syn. E. campylopoda C.A. Mey) lack ephedrine alkaloids and their postulated metabolic precursors 1-phenylpropane-1,2-dione and (S)-cathinone. Solid-phase microextraction analysis of freshly picked young E. sinica and E. foeminea stems revealed the presence of increased benzaldehyde levels in E. foeminea, whereas 1-phenylpropane-1,2-dione was detected only in E. sinica. Soluble protein preparations from E. sinica and E. foeminea stems catalyzed the conversion of benzaldehyde and pyruvate to (R)-phenylacetylcarbinol, (S)-phenylacetylcarbinol, (R)-2-hydroxypropiophenone (S)-2-hydroxypropiophenone and 1-phenylpropane-1,2-dione. The activity, termed benzaldehyde carboxyligase (BCL) required the presence of magnesium and thiamine pyrophosphate and was 40 times higher in E. sinica as compared to E. foeminea. The distribution patterns of BCL activity in E. sinica tissues correlates well with the distribution pattern of the ephedrine alkaloids. (S)-Cathinone reductase enzymatic activities generating (1R,2S)-norephedrine and (1S,1R)-norephedrine were significantly higher in E. sinica relative to the levels displayed by E. foeminea. Surprisingly, (1R,2S)-norephedrine N-methyltransferase activity which is a downstream enzyme in ephedrine biosynthesis was significantly higher in E. foeminea than in E. sinica. Our studies further support that benzaldehyde is the metabolic precursor to phenylpropylamino alkaloids in E. sinica.

  10. Preparation of Natural Zeolite for Air Dehumidification in Food Drying

    Directory of Open Access Journals (Sweden)

    Mohamad Djaeni

    2015-03-01

    Full Text Available Drying with air dehumidification with solid adsorbent improves the quality of food product as well as energy efficiency. The natural zeolite is one of adsorbent having potential to adsorb the water.  Normally, the material was activated to open the pore, remove the organic impurities, and increase Si/Al rate. Hence, it can enhance the adsorbing capacity. This research studied the activation of natural zeolite mined from Klaten, Indonesia as air dehumidification for food drying. Two different methods were used involving activation by heat and NaOH introduction.  As indicators, the porosity and water loaded were evaluated. Results showed both methods improved the adsorbing capacity significantly. With NaOH, the adsorbing capacity was higher. The simple test in onion and corn drying showed the presence of activated natural zeolite can speed up water evaporation positively. This performance was also comparable with Zeolite 3A

  11. 77 FR 28870 - Floridian Natural Gas Storage Company, LLC; Notice of Intent To Prepare an Environmental...

    Science.gov (United States)

    2012-05-16

    ... Energy Regulatory Commission Floridian Natural Gas Storage Company, LLC; Notice of Intent To Prepare an Environmental Assessment for the Floridian Natural Gas Amendment Project and Request for Comments on... environmental assessment (EA) that will discuss the environmental impacts of the Floridan Natural Gas...

  12. Preparation and Characterization of Super Absorbent Resin from Natural Cellulose

    Institute of Scientific and Technical Information of China (English)

    李杰; 马凤国; 谭惠民

    2003-01-01

    The grafting polyacrylamide onto wood pulp cellulose (cell-g-PAM) was performed with cerous ammonium nitrate as the initiator and hydrolyzed to produce the super absorbent resin. The FTIR shows that the polyacrylamide is grafted on the cellulose. After hydrolyzation, part of acrylamino groups are transformed into carboxyl groups. The XRD analysis shows that the graft polymerization occurred at the amorphous section and the surface of the crystal section of cellulose. The SEM graph reveals that there is a layer of polymer on the surface of cellulose fiber and the fibril structure of the cellulose surface is covered. After hydrolyzation, the surface of the product is different from that of cell-g-PAM's and the surface is scraggy. The technical conditions to prepare high water absorbent resin were confirmed. Through the radical graft copolymerization, the high water absorbent resin can be produced from wood pulp cellulose.

  13. Infrared Spectra and Hydrogen Bonds of Biologically Active Benzaldehydes

    Science.gov (United States)

    Tolstorozhev, G. B.; Skornyakov, I. V.; Belkov, M. V.; Shimko, A. N.; Shadyro, O. I.; Brinkevich, S. D.; Samovich, S. N.

    2013-09-01

    IR-Fourier spectra of solutions and crystals of biologically active benzaldehyde derivatives were studied. Specific features of the formation of intra- and intermolecular hydrogen bonds were analyzed. Spectral signatures that characterized participation of the hydroxyl OH group and also the OCH3 and C=O groups in the formation of intramolecular hydrogen bonds of the three different types O-H···O-H, O-H···O-CH3, and O-H···O=C were revealed. Intramolecular hydrogen bonds of the types O-H···O-H and O-H···O-CH3 were absent for benzaldehyde derivatives in the crystal phase. Only hydroxyl and carbonyl groups participated in intermolecular interactions. This resulted in the formation of linear intermolecular dimers. Seven various configurations of the linear dimers were identified in solutions and crystals.

  14. Preparing High School Students for the Interdisciplinary Nature of Modern Biology

    OpenAIRE

    Nagle, Barbara

    2013-01-01

    Preparing students for the interdisciplinary nature of modern biology will require changes in curriculum, instruction, assessments, and teacher professional development in order to support teaching for conceptual understanding and for making cross-disciplinary connections.

  15. Biomass pyrolysis: Thermal decomposition mechanisms of furfural and benzaldehyde

    Science.gov (United States)

    Vasiliou, AnGayle K.; Kim, Jong Hyun; Ormond, Thomas K.; Piech, Krzysztof M.; Urness, Kimberly N.; Scheer, Adam M.; Robichaud, David J.; Mukarakate, Calvin; Nimlos, Mark R.; Daily, John W.; Guan, Qi; Carstensen, Hans-Heinrich; Ellison, G. Barney

    2013-09-01

    The thermal decompositions of furfural and benzaldehyde have been studied in a heated microtubular flow reactor. The pyrolysis experiments were carried out by passing a dilute mixture of the aromatic aldehydes (roughly 0.1%-1%) entrained in a stream of buffer gas (either He or Ar) through a pulsed, heated SiC reactor that is 2-3 cm long and 1 mm in diameter. Typical pressures in the reactor are 75-150 Torr with the SiC tube wall temperature in the range of 1200-1800 K. Characteristic residence times in the reactor are 100-200 μsec after which the gas mixture emerges as a skimmed molecular beam at a pressure of approximately 10 μTorr. Products were detected using matrix infrared absorption spectroscopy, 118.2 nm (10.487 eV) photoionization mass spectroscopy and resonance enhanced multiphoton ionization. The initial steps in the thermal decomposition of furfural and benzaldehyde have been identified. Furfural undergoes unimolecular decomposition to furan + CO: C4H3O-CHO (+ M) → CO + C4H4O. Sequential decomposition of furan leads to the production of HC≡CH, CH2CO, CH3C≡CH, CO, HCCCH2, and H atoms. In contrast, benzaldehyde resists decomposition until higher temperatures when it fragments to phenyl radical plus H atoms and CO: C6H5CHO (+ M) → C6H5CO + H → C6H5 + CO + H. The H atoms trigger a chain reaction by attacking C6H5CHO: H + C6H5CHO → [C6H6CHO]* → C6H6 + CO + H. The net result is the decomposition of benzaldehyde to produce benzene and CO.

  16. [A new benzaldehyde from aerial part of Rehmannia glutinosa].

    Science.gov (United States)

    Zou, Yan; Zhang, Lei; Xu, Jie-kun; Cheng, Qian; Ye, Xian-sheng; Li, Ping; Zhang, Wei-ku; Li, Yong-ji

    2015-04-01

    A new benzaldehyde, 3-hydroxy-4-(4-(2-hydroxyethyl) phenoxy) henzaldehyde(1), together with six known compounds, including isovanillic acid(2), pyrocatechol(3), glutinosalactone A(4), chrysoeriol(5), apigenin(6) and luteolin(7) were isolated from aerial part of Rehmannia glutinosa. The compounds were isolated by macroporous resin, silica gel, Sephadex LH-20 and HPLC chromatographies. The chemical structures of 1-7 were elucidated on the basis of spectral analysis (MS, 1D NMR and 2D NMR).

  17. Biomass pyrolysis: thermal decomposition mechanisms of furfural and benzaldehyde.

    Science.gov (United States)

    Vasiliou, AnGayle K; Kim, Jong Hyun; Ormond, Thomas K; Piech, Krzysztof M; Urness, Kimberly N; Scheer, Adam M; Robichaud, David J; Mukarakate, Calvin; Nimlos, Mark R; Daily, John W; Guan, Qi; Carstensen, Hans-Heinrich; Ellison, G Barney

    2013-09-14

    The thermal decompositions of furfural and benzaldehyde have been studied in a heated microtubular flow reactor. The pyrolysis experiments were carried out by passing a dilute mixture of the aromatic aldehydes (roughly 0.1%-1%) entrained in a stream of buffer gas (either He or Ar) through a pulsed, heated SiC reactor that is 2-3 cm long and 1 mm in diameter. Typical pressures in the reactor are 75-150 Torr with the SiC tube wall temperature in the range of 1200-1800 K. Characteristic residence times in the reactor are 100-200 μsec after which the gas mixture emerges as a skimmed molecular beam at a pressure of approximately 10 μTorr. Products were detected using matrix infrared absorption spectroscopy, 118.2 nm (10.487 eV) photoionization mass spectroscopy and resonance enhanced multiphoton ionization. The initial steps in the thermal decomposition of furfural and benzaldehyde have been identified. Furfural undergoes unimolecular decomposition to furan + CO: C4H3O-CHO (+ M) → CO + C4H4O. Sequential decomposition of furan leads to the production of HC≡CH, CH2CO, CH3C≡CH, CO, HCCCH2, and H atoms. In contrast, benzaldehyde resists decomposition until higher temperatures when it fragments to phenyl radical plus H atoms and CO: C6H5CHO (+ M) → C6H5CO + H → C6H5 + CO + H. The H atoms trigger a chain reaction by attacking C6H5CHO: H + C6H5CHO → [C6H6CHO]* → C6H6 + CO + H. The net result is the decomposition of benzaldehyde to produce benzene and CO.

  18. Photocatalytic oxidation of toluene to benzaldehyde by molecular oxygen

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Y.; Bakac, A. [Ames LAb., IA (United States)]|[Iowa State Univ., Ames, IA (United States)

    1996-03-07

    The visible light irradiation of aqueous solutions containing toluene, uranyl(VI) ions, and O{sub 2} results in the formation of benzaldehyde as a major product. Small amounts of PhCH{sub 2}OH are also formed. The yields of benzaldehyde are 3 times greater for toluene-h{sub 8} than for toluene-d{sub 8}, but the kinetic isotope effect for the quenching of the excited state {sup *}UO{sub 2}{sup 2+} by toluene is negligible (k{sub toluene-h(8)}/k{sub toluene-d(8)}=1.2). This and other evidence indicate that the quenching takes place in two parallel pathways. The major one involves the aromatic portion of tolune and leads to the recovery of the reactants. The minor, productive path takes place by hydrogen atom abstraction from the methyl group, followed by the oxidation of PhCH{sub 2}{sup {center_dot}}. Cumene, benzyl alcohol, and benzaldehyde react similarly. 31 refs., 5 figs., 1 tab.

  19. High efficient photocatalytic selective oxidation of benzyl alcohol to benzaldehyde by solvothermal-synthesized ZnIn2S4 microspheres under visible light irradiation

    Science.gov (United States)

    Chen, Zhixin; Xu, Jingjing; Ren, Zhuyun; He, Yunhui; Xiao, Guangcan

    2013-09-01

    Hexagonal ZnIn2S4 samples have been synthesized by a solvothermal method. Their properties have been determined by X-ray diffraction, ultraviolet-visible-light diffuse reflectance spectra, field emission scanning electron microscopy, nitrogen adsorption-desorption and X-ray photoelectron spectra. These results demonstrate that ethanol solvent has significant influence on the morphology, optical and electronic nature for such marigold-like ZnIn2S4 microspheres. The visible light photocatalytic activities of the ZnIn2S4 have been evaluated by selective oxidation of benzyl alcohol to benzaldehyde using molecular oxygen as oxidant. The results show that 100% conversion along with >99% selectivity are reached over ZnIn2S4 prepared in ethanol solvent under visible light irradiation (λ>420 nm) of 2 h, but only 58% conversion and 57% yield are reached over ZnIn2S4 prepared in aqueous solvent. A possible mechanism of the high photocatalytic activity for selective oxidation of benzyl alcohol over ZnIn2S4 is proposed and discussed.

  20. Proniosomal powders of natural canthaxanthin: Preparation and characterization.

    Science.gov (United States)

    Ravaghi, Maryam; Sinico, Chiara; Razavi, Seyed Hadi; Mousavi, Seyed Mohammad; Pini, Elena; Fadda, Anna Maria

    2017-04-01

    In this study, canthaxanthin (CTX) was produced by Dietzia natronolimnaea HS-1 using beetroot molasses as substrate and used for encapsulation in proniosome powders after extraction, with the aim of improving its stability. Proniosome powders were prepared with an equimolar ratio of span 60/cholesterol and four different carriers, namely maltodextrin, mannitol, lactose and pullulan. The properties of these formulations as both proniosomal powders and resulted niosomal dispersions were evaluated. The type of carriers had significant effects on the micrometric properties of proniosome powders which were further confirmed by the results of SEM analysis. Although light and high temperatures affected the stability of CTX drastically, but encapsulation in proniosomes retarded its degradation. Among these samples, mannitol based proniosome powder (MAPP) produced small vesicles (mean diameter=175±3nmand polydispersity index=0.28±0.02) with the highest entrapment efficiency (74.1±2.7%). MAPP provided a promising formulation to increase CTX stability especially upon storage at high temperatures (45°C).

  1. Recommendations for natural bodybuilding contest preparation: resistance and cardiovascular training.

    Science.gov (United States)

    Helms, E R; Fitschen, P J; Aragon, A A; Cronin, J; Schoenfeld, B J

    2015-03-01

    The anabolic effect of resistance training can mitigate muscle loss during contest preparation. In reviewing relevant literature, we recommend a periodized approach be utilized. Block and undulating models show promise. Muscle groups should be trained 2 times weekly or more, although high volume training may benefit from higher frequencies to keep volume at any one session from becoming excessive. Low to high (~3-15) repetitions can be utilized but most repetitions should occur in the 6-12 range using 70-80% of 1 repetition maximum. Roughly 40-70 reps per muscle group per session should be performed, however higher volume may be appropriate for advanced bodybuilders. Traditional rest intervals of 1-3 minutes are adequate, but longer intervals can be used. Tempo should allow muscular control of the load; 1-2 s concentric and 2-3 s eccentric tempos. Training to failure should be limited when performing heavy loads on taxing exercises, and primarily relegated to single-joint exercises and higher repetitions. A core of multi-joint exercises with some single-joint exercises to address specific muscle groups as needed should be used, emphasizing full range of motion and proper form. Cardiovascular training can be used to enhance fat loss. Interference with strength training adaptations increases concomitantly with frequency and duration of cardiovascular training. Thus, the lowest frequency and duration possible while achieving sufficient fat loss should be used. Full-body modalities or cycling may reduce interference. High intensities may as well; however, require more recovery. Fasted cardiovascular training may not have benefits over fed-state and could be detrimental.

  2. Antitrypanosomal Activity of Novel Benzaldehyde-Thiosemicarbazone Derivatives from Kaurenoic Acid †

    Directory of Open Access Journals (Sweden)

    Cecília M. A. de Oliveira

    2011-01-01

    Full Text Available A series of new thiosemicarbazones derived from natural diterpene kaurenoic acid were synthesized and tested against the epimastigote forms of Trypanosoma cruzi to evaluate their antitrypanosomal potential. Seven of the synthesized thiosemicarbazones were more active than kaurenoic acid with IC50 values between 2-24.0 mM. The o-nitro-benzaldehyde-thiosemicarbazone derivative was the most active compound with IC50 of 2.0 mM. The results show that the structural modifications accomplished enhanced the antitrypanosomal activity of these compounds. Besides, the thiocyanate, thiosemicarbazide and the p- methyl, p-methoxy, p-dimethylamine, m-nitro and o-chlorobenzaldehyde-thiosemicarbazone derivatives displayed lower toxicity for LLMCK2 cells than kaurenoic acid, exhibing an IC50 of 59.5 mM.

  3. Serotonin mediates a learned increase in attraction to high concentrations of benzaldehyde in aged C. elegans.

    Science.gov (United States)

    Tsui, David; van der Kooy, Derek

    2008-11-01

    We utilized olfactory-mediated chemotaxis in Caenorhabditis elegans to examine the effect of aging on information processing and animal behavior. Wild-type (N2) young adults (day 4) initially approach and eventually avoid a point source of benzaldehyde. Aged adult animals (day 7) showed a stronger initial approach and a delayed avoidance to benzaldehyde compared with young adults. This delayed avoidance is due to an increased attraction rather than a decreased avoidance to benzaldehyde because (1) aged odr-3 mutants that are defective in odor attraction showed no delayed benzaldehyde avoidance, and (2) the delay in avoidance was also observed with another attractant diacetyl, but not the repellent octanol. Interestingly, the stronger expression of attractive behavior was only observed at benzaldehyde concentrations of 1% or higher. When worms were grown on nonbacterial growth media instead of Escherichia coli, thus removing the contingency between odors released from the food and the food itself, the increase in attraction to benzaldehyde disappeared. The increased attraction recovered after reinitiating the odor-food contingency by returning animals to E. coli food or supplementing axenic media with benzaldehyde. Moreover, serotonin-deficient mutants showed a deficit in the age-enhanced attraction. These results suggest that the increased attraction to benzaldehyde in aged worms is (1) serotonin mediated, (2) specific to high concentration of odorants, and (3) dependent on a learned association of odor metabolites with the presence of food. We propose that associative learning may selectively modify pathways at or downstream from a low-affinity olfactory receptor.

  4. [Preparation and antimicrobial effect of aromatic, natural and bacteriostatic foot wash with skin care].

    Science.gov (United States)

    Gao, Su-Hua; Zhao, Guo-Xiang; Yang, Xiao-Dong; Xu, Ling-Ling

    2013-06-01

    To prepare the aromatic, natural and bacteriostatic foot wash with skin care and research the inhibition effect on the different bacteria and pathogenic fungus which cause dermatophytosis. It was prepared by using Sophoraflavescens and Dictamnus dasycarpus as materials with the addition of Aloe extract, essential oil, surfactant, etc. The antifungal and antibacterial activity was researched by the levitation liquid quantitative method. The foot wash smelled faintly scent. The use of this product can produce a rich foam. The inhibitory rate were all more than 90%. The preparation process of the foot wash was simple. It has obviously bacteriostatic and fungistatic effect.

  5. Rheological profiling of organogels prepared at critical gelling concentrations of natural waxes in a triacylglycerol solvent

    OpenAIRE

    Patel, Ashok; Babaahmadifooladi, Mehrnoosh; Lesaffer, Ans; Dewettinck, Koen

    2015-01-01

    The aim of this study was to use a detailed rheological characterization to gain new insights into the gelation behavior of natural waxes. To make a comprehensive case, six natural waxes (differing in the relative proportion of chemical components: hydrocarbons, fatty alcohols, fatty acids, and wax esters) were selected as organogelators to gel high-oleic sunflower oil. Flow and dynamic rheological properties of organogels prepared at critical gelling concentrations (Cg) of waxes were studied...

  6. Kinetic secondary deuterium isotope effects for substituted benzaldehyde cyanohydrin formation

    Energy Technology Data Exchange (ETDEWEB)

    Okano, V.; do Amaral, L.; Cordes, E.H.

    1976-07-07

    ..cap alpha.. secondary deuterium isotope effects have been measured for the observed rate constants for addition of cyanide ion to a series of substituted benzaldehydes in aqueous solution at 25/sup 0/C. Under the experimental conditions employed, these reactions did not proceed to completion, and the observed isotope effects were corrected to account for the influence of the reverse reaction employing measured equilibrium constants for cyanohydrin formation and previously determined secondary deuterium isotope effect for the equilibrium constant for 4-methoxybenzaldehyde cyanohydrin formation. In the four cases studied, values of k/sub D//k/sub H/ varied from 1.15 to 1.20, only slightly lower than the calculated maximal value for complete formation of the anionic tetrahedral species which is the immediate product of the rate-determining step, 1.21. A trend in isotope effect as a function of substrate reactivity could not be definitively established. The results suffice to establish that addition of cyanide to benzaldehydes proceeds via transition states in which rehybridization of carbonyl carbon to the tetrahedral geometry is nearly complete.

  7. Reactions of benzaldehyde with trialkylsilyl metal carbonyl complexes

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.L.; Gladysz, J.A.

    1979-10-10

    The use of trialkylsilyl metal carbonyl complexes as reagents for organometallic synthesis was investigated. In this communication it was reported that the metal silanes (CO)/sub 5/MnSi(CH/sub 3/)/sub 3/(1), (CO)/sub 4/Fe(SiCH/sub 3/)/sub 3/)/sub 2/(2), and (CO/sub 4/)FeSi(CH/sub 3/)/sub 2/(CH/sub 2/CH/sub 2/Si(CH/sub 3/)/sub 2/(3) undergo reactions with benzaldehyde which result, under appropriate conditions, in the formation of ..cap alpha..-silyloxybenzyl- and benzylidene-derived ligands. It was reported that a strongly oxygenophilic group must be present on manganese in order for a benzaldehyde adduct to be detectably formed. The catalytic hydrosilyation of aldehydes and ketones has been postulated to involve a similar carbonyl group addition by a catalytically active L/sb n/M(H)SiR/sub 3/ species. The presence of chelating disilane ligand enables the chemistry of 3 to dramaticaly diverge from that of 2. With aliphatic aldehydes and ketones, 1 and 2 react differently. (DP)

  8. Kinetics, thermodynamics, and mechanism of the formation of benzaldehyde-S(IV) adducts

    Energy Technology Data Exchange (ETDEWEB)

    Olson, T.M.; Boyce, S.D.; Hoffmann, M.R.

    1986-05-22

    The kinetics and mechanism of the formation of ..cap alpha..-hydroxyphenylmethanesulfonate (HPMS) by the addition of bisulfite to benzaldehyde were studied at low pH. A three-term rate law was observed as d(HPMS)/dt - (k/sub 1/..cap alpha../sub 2/ + (k/sub 2/ + k/sub 3/K/sub H-/(H/sup +/))..cap alpha../sub 1/)(S(IV))/sub t/(C/sub 6/H/sub 5/CHO) where ..cap alpha../sub 1/ = (HSO/sub 2//sup -/)/(S(IV)), ..cap alpha../sub 3/ = (SO/sub 2//sup 2 -/)/(S(IV)), and K/sub H/ is the proton association constant of benzaldehyde. The rate-limiting steps of each term appeared to be the nucleophilic attack of SO/sub 3//sup 2 -/ on the carbonyl carbon of benzaldehyde, the attack of HSO/sub 3//sup -/ on the carbonyl carbon, and the attack by HSO/sub 3//sup -/ on the protonated carbon of the carbocation, C/sub 6/H/sub 5/C/sup +/H(OH), respectively. Over the pH range of most natural systems, only the k/sub 1/ and k/sub 2/ steps contribute to adduct formation while the k/sub 3/ term becomes important for pH < 1. At 25/sup 0/C and ..mu.. = 1.0 M, the intrinsic rate constants were determined to be k/sub 1/ = (2.15 +- 0.09) x 10/sup 4/ M/sup -1/ s/sup -1/, k/sub 2/ = (0.71 +- 0.03) M/sup -1/ s/sup -1/, k/sub 3/ approx. 2.5 x 10/sup 7/ M/sup -1/ s/sup -1/. Para-substitution on the benzaldehyde ring resulted in a slight increase in reactivity for p-NO/sub 2/- and p-Cl-, and a decrease for p-OH-, p-OCH/sub 3/-, and p-CH/sub 3/-C/sub 6/H/sub 5/CHO. The equilibrium association constant, K = (C/sub 6/H/sub 5/CH(OH)SO/sub 3//sup -/)/(HSO/sub 3//sup -/)(C/sub 6/H/sub 5/CHO), at 25/sup 0/C was determined to be 4.8 (+-0.8) x 10/sup 3/ at ..mu.. = 0.1 M and 0.98 (+- 0.11) x 10/sup 3/ M/sup -1/ at ..mu.. = 1.0 M. ..delta..H/sup 0/ and ..delta..S/sup 0/ was determined to be -64.6 kJ mol/sup -1/ and -146 J mol/sup -1/ deg/sup -1/, respectively.

  9. Preparation of soluble and insoluble polymer supported IBX reagents.

    Science.gov (United States)

    Reed, Neal N; Delgado, Mercedes; Hereford, Kristina; Clapham, Bruce; Janda, Kim D

    2002-08-05

    A series of soluble and insoluble polymer supported versions of the versatile oxidizing reagent IBX has been prepared. Each of the reagents were evaluated for their efficiency in the conversion of benzyl alcohol to benzaldehyde. Results from this study were that the soluble, non-crosslinked polystyrene supported IBX reagent gave the best rate of conversion to benzaldehyde, while the macroporous polymer supported IBX resin provided a superior rate of conversion to benzaldehyde when compared with a gel type resin. The macroporous IBX reagent was also shown to convert a series of alcohols to the corresponding aldehydes and ketones.

  10. Polycondensation of pyrrole and benzaldehyde catalyzed by Maghnite–H+

    Directory of Open Access Journals (Sweden)

    2007-07-01

    Full Text Available Rapid synthesis of poly[(pyrrole-2,5-diyl-co-(benzylidene] was achieved under microwave irradiation via the condensation of pyrrole and benzaldehyde in 1,2-dichloroethane using acid exchanged montmorillonite clay called Maghnite–H+ (Mag–H+ as an efficient catalyst. The effect of the amount of catalyst and of time on the polymerization yield and on the viscosity of the polymers was studied. Compared with conventional static interfacial polymerization, the microwave-radiation polymerization reaction proceeded rapidly and was completed within 35 s. The conjugated polymer was characterized by means of 1H-NMR, X-ray diffraction, FT-IR spectroscopy and AFM. The X-ray data showed the presence of a backbone form of the [(pyrrole-2,5-diyl-co-(benzylidene] formed.

  11. (E-Benzaldehyde (2,4,6-trichlorophenylhydrazone

    Directory of Open Access Journals (Sweden)

    Yan-Lan Huang

    2011-02-01

    Full Text Available The title compound, C13H9Cl3N2, was obtained from a condensation reaction of benzaldehyde and 2,4,6-trichlorophenylhydrazine. The molecule assumes an E configuration with the phenyl ring and trichlorophenyl ring located on opposite sides of the C=N bond. The phenyl ring is oriented at a dihedral angle of 42.58 (12° with respect to the tricholorophenyl ring. In the crystal, the molecules are linked via N—H...N hydrogen bonds, forming supramolecular chains running along the c axis. π–π stacking is present between parallel trichlorophenyl rings of adjacent molecules, the face-to-face and centroid–centroid distances being 3.369 (14 and 3.724 (2 Å, respectively.

  12. Explorations of Crystalline Effects on 4-(Benzyloxy)Benzaldehyde Properties

    Science.gov (United States)

    Harismah, Kun; Ozkendir, O. Murat; Mirzaei, Mahmoud

    2015-12-01

    The properties of 4-(benzyloxy)benzaldehyde (BBA), as a pharmaceutically important compound, have been investigated through the density functional theory (DFT) calculations. The properties of original crystalline and optimised gaseous structures have been evaluated to recognise the crystalline effects. In addition to the structural properties, nuclear magnetic resonance (NMR) properties have also been evaluated for both investigated systems to better detect the effects in atomic levels. The results indicated that the structural shape of BBA is significantly changed in the optimised gaseous system, showing significant crystalline effects on the geometrical positions. Moreover, the magnitudes for energies and dipole moments indicate notable effects on the electronic properties. The evaluated NMR properties also show that the atoms of aromatic systems detect significant changes more than the atoms of aliphatic systems in the investigated BBA. And finally, the oxygen bridge atom plays a dominant role in combining two benzene rings of BBA.

  13. Gas Phase Selective Catalytic Oxidation of Toluene to Benzaldehyde on V2O5-Ag2O/η-Al2O3 Catalyst

    Institute of Scientific and Technical Information of China (English)

    Tonglai Zhang; Liqiu Mao; Weihua Liu

    2004-01-01

    Gas phase selective catalytic oxidation of toluene to benzaldehyde was studied on V2O5-Ag2O/η-Al2O3 catalyst prepared by impregnation. The catalyst was characterized by XRD, XPS, TEM,and FT-IR. The catalytic results showed that toluene conversion and selectivity for benzaldehyde on catalyst sample No.4 (V/(V+Ag)=0.68) was higher than other catalysts with different V/Ag ratios. This was attributed to the higher surface area, larger pore volume and pore diameter of the catalyst sample No.4 than the other catalysts. The XRD patterns recorded from the catalyst before and after the oxidation reaction revealed that the new phases were developed, and this suggested that silver had entered the vanadium lattice. XPS results showed that the vanadium on the surface of No.4 and No.5 sample was more than that in the bulk, thus forming a vanadium rich layer on the surface. It was noted that when the catalyst was doped by potassium promoter, the toluene conversion and selectivity for benzaldehyde were higher than those on the undoped catalyst. This was attributed to the disordered structure of V2O5 lattice of the K-doped catalyst and a better interfacial contact between the particles.

  14. Selective liquid phase oxidation of benzyl alcohol to benzaldehyde by tert-butyl hydroperoxide over γ-Al2O3 supported copper and gold nanoparticles

    Science.gov (United States)

    Ndolomingo, Matumuene Joe; Meijboom, Reinout

    2017-03-01

    Benzyl alcohol oxidation to benzaldehyde was performed by tert-butyl hydroperoxide (TBHP) in the absence of any solvent using γ-Al2O3 supported copper and gold nanoparticles. Li2O and ionic liquids were used as additive and stabilizers for the synthesis of the catalysts. The physico-chemical properties of the catalysts were characterized by atomic absorption spectroscopy (AAS), X-ray diffraction spectroscopy (XRD), N2 absorption/desorption (BET), transmission electron microscopy (TEM), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and temperature programmed reduction (TPR), whereas, the oxidation reaction was followed by gas chromatography with a flame ionization detector (GC-FID). The as prepared catalysts exhibited good catalytic performance in terms of conversion and selectivity towards benzaldehyde. The performance of the Au-based catalysts is significantly higher than that of the Cu-based catalysts. For both Cu and Au catalysts, the conversion of benzyl alcohol increased as the reaction proceeds, while the selectivity for benzaldehyde decreased. Moreover, the catalysts can be easily recycled and reused with neither significant loss of activity nor selectivity. A kinetic study for the Cu and Au-catalyzed oxidation of benzyl alcohol to benzyldehyde is reported. The rate at which the oxidation of benzyl alcohol is occurring as a function of catalyst and oxidant amounts was investigated, with the apparent rate constant, kapp being proportional to the amount of nano catalyst and oxygen present in the system.

  15. Desymmetrization of 7-azabicycloalkenes by tandem olefin metathesis for the preparation of natural product scaffolds

    Directory of Open Access Journals (Sweden)

    Deppermann Nina

    2007-12-01

    Full Text Available Abstract Background Tandem olefin metathesis sequences are known to be versatile for the generation of natural product scaffolds and have also been used for ring opening of strained carbo- and heterocycles. In this paper we demonstrate the potential of these reactions for the desymmetrization of 7-azabicycloalkenes. Results We have established efficient protocols for the desymmetrization of different 7-azabicycloalkenes by intra- and intermolecular tandem metathesis sequences with ruthenium based catalysts. Conclusion Desymmetrization of 7-azabicycloalkenes by olefin metathesis is an efficient process for the preparation of common natural product scaffolds such as pyrrolidines, indolizidines and isoindoles.

  16. Desymmetrization of 7-azabicycloalkenes by tandem olefin metathesis for the preparation of natural product scaffolds

    Science.gov (United States)

    Maison, Wolfgang; Büchert, Marina; Deppermann, Nina

    2007-01-01

    Background Tandem olefin metathesis sequences are known to be versatile for the generation of natural product scaffolds and have also been used for ring opening of strained carbo- and heterocycles. In this paper we demonstrate the potential of these reactions for the desymmetrization of 7-azabicycloalkenes. Results We have established efficient protocols for the desymmetrization of different 7-azabicycloalkenes by intra- and intermolecular tandem metathesis sequences with ruthenium based catalysts. Conclusion Desymmetrization of 7-azabicycloalkenes by olefin metathesis is an efficient process for the preparation of common natural product scaffolds such as pyrrolidines, indolizidines and isoindoles. PMID:18088413

  17. Preparation and characterization of silver nanoparticles in natural polymers using laser ablation

    Indian Academy of Sciences (India)

    Reza Zamiri; B Z Azmi; Hossein Abbastabar Ahangar; Golnoosh Zamiri; M Shahril Husin; Z A Wahab

    2012-10-01

    In this paper we have done a comparative study on efficiency of natural polymers for stabilizing silver nanoparticles (Ag-NPs) prepared by laser ablation technique. The selected polymers are starch (St), gelatin (Gt) and chitosan (Ct). The fabrication process was carried out through ablation of a pure Ag plate by nanosecond Q-switched Nd–Yg pulsed laser ( = 532 nm, 360 mJ/pulse). The stability of the samples was studied by measuring UV-visible absorption spectra of the samples one month after preparation. The result showed that the formation efficiency of NPs in St were highest and also the prepared NPs in St solution were more stable than other polymers during one month storage.

  18. Properties of natural rubber/attapulgite composites prepared by latex compounding method: Effect of filler loading

    Energy Technology Data Exchange (ETDEWEB)

    Muttalib, Siti Nadzirah Abdul, E-mail: sitinadzirah.amn@gmail.com; Othman, Nadras, E-mail: srnadras@usm.my; Ismail, Hanafi, E-mail: ihanafi@usm.my [School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, 14300 Nibong Tebal, Pulau Pinang (Malaysia)

    2015-07-22

    This paper reports on the effect of filler loading on properties of natural rubber (NR)/attapulgite (ATP) composites. The NR/ATP composites were prepared by latex compounding method. It is called as masterbatch. The masterbatch was subsequently added to the NR through melt mixing process. The vulcanized NR/ATP composites were subjected to mechanical, swelling and morphological tests. All the results were compared with NR/ATP composites prepared by conventional system. The composites from masterbatch method showed better results compared to composites prepared by conventional method. They have higher tensile properties, elongation at break and tear strength. The images captured through scanning electron microscopy test revealed the improvement of tensile strength in masterbatch NR/ATP composites. It can be seen clearly that masterbatch NR/ATP have better filler dispersion compared to conventional method NR/ATP composites.

  19. Physical and Degradable Properties of Mulching Films Prepared from Natural Fibers and Biodegradable Polymers

    OpenAIRE

    Zhijian Tan; Yongjian Yi; Hongying Wang; Wanlai Zhou; Yuanru Yang; Chaoyun Wang

    2016-01-01

    The use of plastic film in agriculture has the serious drawback of producing vast quantities of waste. In this work, films were prepared from natural fibers and biodegradable polymers as potential substitutes for the conventional non-biodegradable plastic film used as mulching material in agricultural production. The physical properties (e.g., mechanical properties, heat preservation, water permeability, and photopermeability) and degradation characteristics (evaluated by micro-organic cultur...

  20. Bioproduction of benzaldehyde in a solid-liquid two-phase partitioning bioreactor using Pichia pastoris.

    Science.gov (United States)

    Jain, Ashu N; Khan, Tanya R; Daugulis, Andrew J

    2010-11-01

    The bioproduction of benzaldehyde from benzyl alcohol using Pichia pastoris was examined in a solid-liquid two-phase partitioning bioreactor (TPPB) to reduce substrate and product inhibition. Rational polymer selection identified Elvax 40W as an effective sequestering phase, possessing partition coefficients for benzyl alcohol and benzaldehyde of 3.5 and 35.4, respectively. The use of Elvax 40W increased the overall mass of benzaldehyde produced by approx. 300% in a 5 l bioreactor, relative to a single phase biotransformation. The two-phase system had a molar yield of 0.99, indicating that only minor losses occurred. These results provide a promising starting point for solid-liquid TPPBs to enhance benzaldehyde production, and suggest that multiple, targeted polymers may provide relief for transformations characterized by multiple inhibitory substrates/product/by-products.

  1. Synthesis, complexation, spectral, antibacterial and antifungal activity of 2,4-dihydroxy-5-[(E-phenyldiazenyl]benzaldehyde oxime

    Directory of Open Access Journals (Sweden)

    MÜKERREM KURTOGLU

    2010-09-01

    Full Text Available A new substituted salicylaldoxime ligand containing an azo (–N=N– group, 2,4-dihydroxy-5-[(E-phenyldiazenyl]benzaldehyde oxime (H3salox (2, was synthesized by the reaction of 2,4-dihydroxy-5-[(E-phenyldiazenyl]benzaldehyde (1 with hydroxylamine in ethanolic solution at room temperature. Mononuclear complexes of (H3salox (2, a bidentate hydroxyaldoxime ligand, were synthesized by reaction with nickel(II, cobalt(II and copper(II chloride salts. The complexes, [Ni(H2salox2] (3, [Cu(H2salox2] (4 and [Co(H2salox2] (5 were characterized by elemental analyses (C, H, N, conductivity measurements and infrared and electronic spectral studies. The 1H-NMR spectrum of the H3salox (2 ligand was also recorded. The mononuclear Ni(II, Co(II and Cu(II complexes of the ligand, (H3salox, have a metal:ligand ratio of 1:2 and the ligand coordinates through the N and O atoms, as is the case with most hydroxyaldoximes. The molar conductivities in DMF solution indicate the non-electrolytic nature of the metal chelates. The antimicrobial activities of the ligand and its metal complexes were estimated for eight bacteria, i.e., Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Mycobacterium smegmatis, Pseudomonas aeruginosa, Enterococcus cloacae, Bacillus megaterium and Micrococcus luteus and three fungi, i.e., Kluyveromyces fragilis, Rhodotorula rubra and Saccharomyces cerevisiae.

  2. Isotope effect in the reaction of cumyl peroxide radical with benzaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Simonov, M.A.; Opeida, I.A.; Romantsevich, A.M.

    1986-08-01

    The rate constants for reaction of cumyl peroxide with benzaldehyde and benzaldehyde-D/sub 1/ have been measured; k /SUP H/ = 10 /SUP 7.61+or-0.18/ exp((-9.2 + or - 0.3)/RT) and k /SUP D/ = 10 /SUP 7.31+or-0.40/ exp ((-10.8 + or - 0.6)/RT) liter/mole.sec, respectively.

  3. Benzaldehyde as an insecticidal, antimicrobial, and antioxidant compound produced by Photorhabdus temperata M1021.

    Science.gov (United States)

    Ullah, Ihsan; Khan, Abdul Latif; Ali, Liaqat; Khan, Abdur Rahim; Waqas, Muhammad; Hussain, Javid; Lee, In-Jung; Shin, Jae-Ho

    2015-02-01

    The Photorhabdus temperata M1021 secretes toxic compounds that kill their insect hosts by arresting immune responses. Present study was aimed to purify the insecticidal and antimicrobial compound(s) from the culture extract of P. temperata M1021 through bioassay guided fractionation. An ethyl acetate (EtOAc) extract of the P. temperata M1021 exhibited 100% mortality in Galleria mellonella larvae within 72 h. In addition, EtOAc extract and bioactive compound 1 purified form the extract through to column chromatography, showed phenol oxidase inhibition up to 60% and 80% respectively. The analysis of (1)H and (13)C NMR spectra revealed the identity of pure compound as "benzaldehyde". The benzaldehyde showed insecticidal activity against G. mellonella in a dose-dependent manner and 100% insect mortality was observed at 108 h after injection of 8 mM benzaldehyde. In a PO inhibition assay, 4, 6, and 8 mM concentrations of benzaldehyde were found to inhibit PO activity about 15%, 42%, and 80% respectively. In addition, nodule formation was significantly (P benzaldehyde as compare to control. Moreover, benzaldehyde was found to have great antioxidant activity and maximum antioxidant activity was 52.9% at 8 mM benzaldehyde as compare to control. Antimicrobial activity was assessed by MIC values ranged from 6 mM 10 mM for bacterial strains and 8 mM to 10 mM for fungal strains. The results suggest that benzaldehyde could be applicable for developing novel insecticide for agriculture use.

  4. Influence of Photosensitive Group Concentration on Birefringence Induced in Benzaldehyde Polymers

    Science.gov (United States)

    Mahilny, U. V.; Stankevich, A. I.; Trofimova, A. V.

    2014-01-01

    Induction of optical anisotropy in benzaldehyde polymer layers by linearly polarized UV radiation was investigated experimentally. Negative dichroism in absorption spectra and strong negative birefringence (-2 · 10-3) were related to the presence of an oriented ensemble of residual benzaldehyde groups. The thermal stability of photoinduced birefringence at high photosensitive group concentration was associated with a high density of photocross-links formed between macromolecules.

  5. Preparation of activated carbon from waste plastics polyethylene terephthalate as adsorbent in natural gas storage

    Science.gov (United States)

    Yuliusman; Nasruddin; Sanal, A.; Bernama, A.; Haris, F.; Ramadhan, I. T.

    2017-02-01

    The main problem is the process of natural gas storage and distribution, because in normal conditions of natural gas in the gas phase causes the storage capacity be small and efficient to use. The technology is commonly used Compressed Natural Gas (CNG) and Liquefied Natural Gas (LNG). The weakness of this technology safety level is low because the requirement for high-pressure CNG (250 bar) and LNG requires a low temperature (-161°C). It takes innovation in the storage of natural gas using the technology ANG (Adsorbed Natural Gas) with activated carbon as an adsorbent, causing natural gas can be stored in a low pressure of about 34.5. In this research, preparation of activated carbon using waste plastic polyethylene terephthalate (PET). PET plastic waste is a good raw material for making activated carbon because of its availability and the price is a lot cheaper. Besides plastic PET has the appropriate characteristics as activated carbon raw material required for the storage of natural gas because the material is hard and has a high carbon content of about 62.5% wt. The process of making activated carbon done is carbonized at a temperature of 400 ° C and physical activation using CO2 gas at a temperature of 975 ° C. The parameters varied in the activation process is the flow rate of carbon dioxide and activation time. The results obtained in the carbonization process yield of 21.47%, while the yield on the activation process by 62%. At the optimum process conditions, the CO2 flow rate of 200 ml/min and the activation time of 240 minutes, the value % burn off amounted to 86.69% and a surface area of 1591.72 m2/g.

  6. 77 FR 71585 - Eastern Shore Natural Gas Company; Notice of Intent To Prepare an Environmental Assessment for...

    Science.gov (United States)

    2012-12-03

    ... two new 1,775 nominal horsepower (hp) natural gas-fired reciprocating compressor engines at its...; Constructing two new Caterpillar model 3606 TALE 1,775 hp natural gas-fired reciprocating compressor engines... Energy Regulatory Commission Eastern Shore Natural Gas Company; Notice of Intent To Prepare an...

  7. Preparation and Properties of Biocomposite Based on Natural Rubber and Bagasse Nanocellulose

    Directory of Open Access Journals (Sweden)

    Jarnthong Methakarn

    2015-01-01

    Full Text Available Biocomposite based on natural rubber (NR and bagasse nanocellulose (BNC was prepared in latex state. The mechanical, morphological and thermal properties of NR/BNC biocomposite were investigated. It was found that the addition of 3 wt% of BNC in NR film caused significant increase in modulus at 100% and 300% elongations and improved thermal stability of NR/BNC biocomposite. However, the strength at break and elongation at break of the biocomposite were not enhanced correlating to the morphological result obtained from scanning electron microscope (SEM.

  8. Electrosynthesis in room-temperature ionic liquids: benzaldehyde reduction

    Energy Technology Data Exchange (ETDEWEB)

    Doherty, Andrew P.; Brooks, Claudine A

    2004-09-15

    The electrochemical reduction of benzaldehyde at Pt microelectrodes in 1-butyl-1-methyl pyrrolidinium triflimide ([Bmpyr][NTF{sub 2}]) room temperature ionic liquid is reported. At high potential sweep rates (>1000 V s{sup -1}) reduction occurs as two reversible one-electron reduction processes corresponding to the reversible formation of the radical anion (at -1.6 V versus Pt) and the dianion species (at -2.2 V versus Pt). The second order rate constant for radical anion-radical anion dimerisation was 1.4x10{sup 4} mol{sup -1} dm{sup 3} s{sup -1}, while the pseudo-first-order rate constant for the subsequent formation of the alcohol (or electroinactive alcoholate) was 1000 s{sup -1}. Kinetically, the electrochemistry is similar to that in acetonitrile or alkaline ethanol. At lower potential sweep rates, a third irreversible reduction occurs which appears to be the reduction of the pyrrolidinium cation as an ion-associated species with the anion products of the initial reductions.

  9. Assessment of cytotoxic and apoptotic effects of benzaldehyde using different assays.

    Science.gov (United States)

    Ulker, Z; Alpsoy, L; Mihmanli, A

    2013-08-01

    Benzaldehyde (BA) occurs naturally in a number of plants, including cherry, fig and peach fruit and carnation flowers at therapeutic doses. In addition, it is used in cosmetics, personal care products and food as a preservative. In this study, we aimed to determine the cytotoxic and apoptotic effects of different concentrations of BA on cultured human lymphocytes using lactate dehydrogenase assay, cell proliferation (water-soluble tetrazolium salts-1) assay and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) test (apoptotic test) as a group of cytotoxicity tests at 6th and 24th h on human lymphocyte cell culture. The cytotoxicity increased when cells were treated with 10, 25 and 50 μg/mL concentrations of BA (p < 0.05). Moreover, treatment of the cells with the same concentrations significantly decreased the cell number at the 6th and 24th hours (p < 0.05). TUNEL assay results also show that the concentration of BA at 10, 25 and 50 μg/mL caused DNA damage significantly (p < 0.05). According to our results, the toxic and genotoxic effects of BA have to be further evaluated before using in cosmetic and food products.

  10. Preparation of hydrogels for atopic dermatitis containing natural herbal extracts by gamma-ray irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Youn-Mook; An, Sung-Jun; Kim, Hae-Kyoung [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong Jeongeup-si Jellabuk-do, 580-185 (Korea, Republic of); Kim, Yun-Hye [AMOTECH Co., Ltd., Kimpo-City, Kyungki-do (Korea, Republic of); Youn, Min-Ho; Gwon, Hui-Jeong; Shin, Junhwa [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong Jeongeup-si Jellabuk-do, 580-185 (Korea, Republic of); Nho, Young-Chang [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong Jeongeup-si Jellabuk-do, 580-185 (Korea, Republic of)], E-mail: ycnho@kaeri.re.kr

    2009-07-15

    Atopic dermatitis (AD) is a familial and chronic inflammatory pruritic skin disease that affects a large number of children and adults in industrialized countries. It is known that one of the prominent features of AD and chronic pruritus is partially due to the histamine released from mast cell. In this work, hydrogel patches with natural herbal extracts were prepared by 'freezing and thawing', and a gamma irradiation. It showed eminent healing results as a consequence of long-term moisturizing effects and natural herbal extracts on atopic wounds. Besides its non-toxicity and human harmlessness, it can be easily attached to or detached from the skin without any trace and help patients to feel refreshment when attached. Based on this work, the hydrogel patches we made can be potentially used as an alternative remedy for not only pruritus in AD, but other dermatitis.

  11. Mechanism of benzaldehyde lyase studied via thiamin diphosphate-bound intermediates and kinetic isotope effects.

    Science.gov (United States)

    Chakraborty, Sumit; Nemeria, Natalia; Yep, Alejandra; McLeish, Michael J; Kenyon, George L; Jordan, Frank

    2008-03-25

    Direct spectroscopic observation of thiamin diphosphate-bound intermediates was achieved on the enzyme benzaldehyde lyase, which carries out reversible and highly enantiospecific conversion of ( R)-benzoin to benzaldehyde. The key enamine intermediate could be observed at lambda max 393 nm in the benzoin breakdown direction and in the decarboxylase reaction starting with benzoylformate. With benzaldehyde as substrate, no intermediates could be detected, only formation of benzoin at 314 nm. To probe the rate-limiting step in the direction of ( R)-benzoin synthesis, the (1)H/ (2)H kinetic isotope effect was determined for benzaldehyde labeled at the aldehyde position and found to be small (1.14 +/- 0.03), indicating that ionization of the C2alphaH from C2alpha-hydroxybenzylthiamin diphosphate is not rate limiting. Use of the alternate substrates benzoylformic and phenylpyruvic acids (motivated by the observation that while a carboligase, benzaldehyde lyase could also catalyze the slow decarboxylation of 2-oxo acids) enabled the observation of the substrate-thiamin covalent intermediate via the 1',4'-iminopyrimidine tautomer, characteristic of all intermediates with a tetrahedral C2 substituent on ThDP. The reaction of benzaldehyde lyase with the chromophoric substrate analogue ( E)-2-oxo-4(pyridin-3-yl)-3-butenoic acid and its decarboxylated product ( E)-3-(pyridine-3-yl)acrylaldehyde enabled the detection of covalent adducts with both. Neither adduct underwent further reaction. An important finding of the studies is that all thiamin-related intermediates are in a chiral environment on benzaldehyde lyase as reflected by their circular dichroism signatures.

  12. Preparation and characterization of hybrid materials from natural chrysotile; Preparacao e caracterizacao de materiais hibridos a partir da crisotila natural

    Energy Technology Data Exchange (ETDEWEB)

    Giraldelli, M.G.; Silva, M.L.C.P., E-mail: marciogiraldelli@hotmail.co [Universidade de Sao Paulo (EEL/USP), Lorena, SP (Brazil). Escola de Engenharia

    2010-07-01

    Special attention has been given to the development of new materials from natural chrysotile. This fiber has about 40% silicon oxide in its structure with an outer layer of brucite (MgOH{sub 2}). With the aim of obtaining a material with a more uniform structure, acid leaching was performed to remove the outer layer of brucite, resulting in a silicon oxide hydrate. This material was used as support for the deposition of Nb{sub 2}O{sub 5}.nH{sub 2}O. The Nb{sub 2}O{sub 5}.nH{sub 2}O was prepared by conventional precipitation using as starting material niobium metallic. In this study, we performed the synthesis and characterization of the material SiO{sub 2}.nH{sub 2}O / Nb{sub 2}O{sub 5}.nH{sub 2}O 1:1. Both chrysotile as niobium are widely available national resources, which confirms the economic viability of resource use. The materials studied were characterized by XRD, SEM and TG/DTG. (author)

  13. Biophysical inhibition of synthetic vs. naturally-derived pulmonary surfactant preparations by polymeric nanoparticles.

    Science.gov (United States)

    Beck-Broichsitter, Moritz; Ruppert, Clemens; Schmehl, Thomas; Günther, Andreas; Seeger, Werner

    2014-01-01

    Reasonable suspicion has accumulated that inhaled nano-scale particulate matter influences the biophysical function of the pulmonary surfactant system. Hence, it is evident to provide novel insights into the extent and mechanisms of nanoparticle-surfactant interactions in order to facilitate the fabrication of safe nanomedicines suitable for pulmonary applications. Negatively- and positively-charged poly(styrene) nanoparticles (diameters of ~100nm) served as model carriers. Nanoparticles were incubated with several synthetic and naturally-derived pulmonary surfactants to characterize the sensitivity of each preparation to biophysical inactivation. Changes in surface properties (i.e. adsorption and dynamic surface tension behavior) were monitored in a pulsating bubble surfactometer. Both nanoparticle formulations revealed a dose-dependent influence on the biophysical behavior of all investigated pulmonary surfactants. However, the surfactant sensitivity towards inhibition depended on both the carrier type, where negatively-charged nanoparticles showed increased inactivation potency compared to their positively-charged counterparts, and surfactant composition. Among the surfactants tested, synthetic mixtures (i.e. phospholipids, phospholipids supplemented with surfactant protein B, and Venticute®) were more susceptible to surface-activity inhibition as the more complex naturally-derived preparations (i.e. Alveofact® and large surfactant aggregates isolated from rabbit bronchoalveolar lavage fluid). Overall, nanoparticle characteristics and surfactant constitution both influence the extent of biophysical inhibition of pulmonary surfactants.

  14. Morphology, Tensile Strength and Oil Resistance of Gum Rubber Sheets Prepared from Lignin Modified Natural Rubber

    Directory of Open Access Journals (Sweden)

    Asrul M.

    2014-07-01

    Full Text Available The paper describes the preparation of lignin filled natural rubber latex composite and its subsequent use to obtain lignin modified rubber. Two types of lignin i.e.: rubber wood and commercial alkali lignin were used as rubber filler. Gum rubber sheets were prepared from the lignin modified rubber and their properties were compared to Standard Malaysian Rubber (SMR 20 and a type of rubber obtained from the coagulation of high ammonia latex. Rubber morphology was investigated using Scanning Electron Microscope on the cross-sectional area of cryo-fractured samples. Oil resistance of the rubber sheets was determined by measuring the mass change before and after ASTM IRM 903 oil immersion, while the tensile strengths were determined according to ASTM D412 standard. Low values of tensile strength obtained for the commercial alkali lignin modified rubber sheet relative to the rest of the rubber samples was attributed to poor lignin dispersion. This occurrence was substantiated by the SEM analysis of cryo-fractured samples where crazes and inhomogeneity was observed. Nonetheless, both lignin modified rubbers exhibited higher level of oil resistance compared to SMR 20. This is due to the nature of lignin as a hydrophilic component and its presence in the rubber matrix complicates the oil diffusion process into rubber.

  15. Anaerobic degradation of benzaldehyde in methanogenic granular sludge: the influence of additional substrates

    Energy Technology Data Exchange (ETDEWEB)

    Todini, O. (Environment Protection Dept., Eniricerche S.p.A., Rome (Italy)); Pol, L.H. (Wageningen Agricultural Univ. (Netherlands). Dept. of Environmental Technology)

    1992-12-01

    The degradation of benzaldehyde in methaogenic granular sludge was investigated in batch and in upflow anaerobic sludge blanked (UASB) reactors. The effect due to the presence of co-substrates, such as H[sub 2], sodium butyrate and sucrose, was studied using formaldehyde as a reference compound. The additional substrates enhanced the activity of benzaldehyde- and formaldehyde-degrading microorganisms (ACT[sub bdm] and ACT[sub fdm], respectively) and increased the transient production of benzyl alcohol and methanol. As a consequence, the concentrations of benzaldehyde and formaldehyde that caused 50% inhibition of the methanogenic activity (50% IC[sub m]) on sucrose were 3133 and 254 mg chemical oxygen demand (COD)/1 respectively, three times higher than the literature data values on acetate. Experiments performed in UASB reactors on benzaldehyde showed that the replacement of volatile fatty acids with sucrose as co-substrate improved the treatment capacity of the system from 0.73 to 4.36 kg COD benzaldehyde.m[sup -3].day[sup -1]. (orig.).

  16. Production of L-phenylacetylcarbinol (L-PAC) from benzaldehyde using partially purified pyruvate decarboxylase (PDC).

    Science.gov (United States)

    Shin, H S; Rogers, P L

    1996-01-05

    Biotransformation of benzaldehyde to L-phenylacetylcarbinol (L-PAC) as a key intermediate for L-ephedrine synthesis has been evaluated using pyruvate decarboxylase (PDC) partially purified from Candida utilis. PDC activity was enhanced by controlled fermentative metabolism and pulse feeding of glucose prior to the enzyme purification. With partially purified PDC, several enzymatic reactions occurred simultaneously and gave rise to by-products (acetaldehyde and acetoin) as well as L-PAC production. Optimal reaction conditions were determined for temperature, pH, addition of ethanol, PDC activity, benzaldehyde, and pyruvate:benzaldehyde ratio to maximize L-PAC, and minimize by-products. The highest L-PAC concentration of 28.6 g/L (190.6 mM) was achieved at 7 U/mL PDC activity and 200 mM benzaldehyde with 2.0 molar ratio of pyruvate to benzaldehyde in 40 mM potassium phosphate buffer (pH 7.0) containing 2.0 M ethanol at 4 degrees C.

  17. Preparation and application of reversed phase chromatorotor for the isolation of natural products by centrifugal preparative chromatography

    Science.gov (United States)

    A method of preparation of Chromatorotor or plates with a reversed phase (RP) solid silica gel sorbent layer has been developed for preparative centrifugal chromatography. The RP-rotor plates consist of binder free RP solid SiO2 sorbent layers of different thicknesses paked between two supported cir...

  18. 3nπ* spectra of benzaldehyde II. In methylcyclohexane

    Science.gov (United States)

    Goodman, Lionel; Lamotte, Michel; Koyanagi, Mitohiko

    1980-04-01

    Two active nontotally symmetric coupling modes, v26 and v36 (the out-of-plane aldehyde carbon—hydrogen wagging, and torsional vibrations, respectively) are observed in the 3nπ* TS o spectra of isotopic benzaldehydes at 4.2 K in polycrystalline α-phase methylcyclohexane and β-phase methylcyclohexane- d14. The single quantum band strengths are in the order I(36 01 ≫ I(26 10), I(26 10 ≫ I(26 01, and I(26 10 ≫ I(36 10). The much greater intensity of the double quantum band 26 02 ( I(26 02) ≫ I(26 01)) is largely accounted for by the large frequency difference ω 26 ( 3nπ*)-ω 26(S 0 ≈ -600 cm -1. Displacement factors are found for the principal Franck-Condon modes, v25, v7, v8, v9 and v17. The T ← S 0 spectra dramatically broaden at ≈ 400 cm -1 above the 3nπ* origin with much of the spectra up to ≈ 1200 cm -1 above 0-0 unique to each isomer in each host. Above 1200 cm -1 intense narrow bands are again observed for which counterparts in each of the isomers can be found. Important medium dependencies of the 1.3nπ* 0 point interval, and the OO band CHO → CDO deuterium shift (+25 cm -1 and + 10 cm -1, respectively) are found on going from the vapor to methylcyclohexane. The spectra and medium shifts are interpreted as arising from intersection of zero order nπ* and ππ* potential surfaces. Several excited state ( 3nπ*) vibrational frequencies including ω' 7 = 1316, ω' 17 = 1181, ω' 8 and/or ω' 9 = 1540, 1466 ω' 15 = 1295 and ω' 25 (δCHO) = 190 cm -1 in MCH and ω' 26 = 419 cm -1 in MCH- d14 are established.

  19. Biotransformation of Benzaldehyde to L-Phenylacetylcarbinol (L-PAC) by Free Cells of Torulaspora delbrueckii in presence of Beta-Cyclodextrin

    OpenAIRE

    Shukla,Vilas. B.; Kulkarni,Pushpa R.

    2002-01-01

    Studies were carried out to explore the possibility of decreasing the toxic and inhibitory effects of the substrate benzaldehyde during its biotransformation to L-PAC by free cells of Torulaspora delbrueckii using beta -cyclodextrin (beta -CD). Use of various levels of benzaldehyde and acetaldehyde in presence of 2% of beta -CD showed that, in presence of beta -CD, the organism could tolerate higher levels of benzaldehyde and acetaldehyde. Semi-continuous feeding of benzaldehyde and acetaldeh...

  20. 76 FR 5578 - PetroLogistics Natural Gas Storage Company, LLC; Notice of Intent To Prepare an Environmental...

    Science.gov (United States)

    2011-02-01

    ... Energy Regulatory Commission PetroLogistics Natural Gas Storage Company, LLC; Notice of Intent To Prepare... on Environmental Issues January 25, 2011. The staff of the Federal Energy Regulatory Commission (FERC...Logistics Natural Gas Storage Company, LLC (PetroLogistics) in Iberville Parish, Louisiana. This EA will be...

  1. A Kinetic Model for Toluene Oxidation Comprising Benzylperoxy Benzoate Ester as Reactive Intermediate in the Formation of Benzaldehyde

    NARCIS (Netherlands)

    Hoorn, J.A.A.; Alsters, P.L.; Versteeg, G.F.

    2005-01-01

    During the oxidation of toluene under semibatch conditions, the formation of benzyl alcohol is initially equal to the rate of formation of benzaldehyde. As the overall conversion increases the benzyl alcohol concentration at first decreases much faster than benzaldehyde, but this decrease slows down

  2. A kinetic model for toluene oxidation comprising benzylperoxy benzoate ester as reactive intermediate in the formation of benzaldehyde

    NARCIS (Netherlands)

    Hoorn, J.A.A.; Alsters, P. L.; Versteeg, G. F.

    2005-01-01

    During the oxidation of toluene under semibatch conditions, the formation of benzyl alcohol is initially equal to the rate of formation of benzaldehyde. As the overall conversion increases the benzyl alcohol concentration at first decreases much faster than benzaldehyde, but this decrease slows down

  3. A kinetic model for toluene oxidation comprising benzylperoxy benzoate ester as reactive intermediate in the formation of benzaldehyde

    NARCIS (Netherlands)

    Hoorn, J.A.A.; Alsters, P. L.; Versteeg, G. F.

    2005-01-01

    During the oxidation of toluene under semibatch conditions, the formation of benzyl alcohol is initially equal to the rate of formation of benzaldehyde. As the overall conversion increases the benzyl alcohol concentration at first decreases much faster than benzaldehyde, but this decrease slows down

  4. Environmental education as preparation people for life in conditions of global changes imbalanced Nature

    Science.gov (United States)

    Dabrowska, A. E.

    2013-12-01

    The Regional Teacher Training Centre in Skierniewice is one of 49 public, accredited institutions in Poland. It is responsible for organizing of support of schools, institutions, networks of teachers and school managers for cooperation and self education, organizing and conducting forms of in-service training, giving methodological councils and disseminating examples of good practice. I present one example of how Environmental Education has been imparted to school students and their teachers through outdoor activities as part of the learning process. An Environmental Education Program, 'On Bolimov Nature Preserve Trails' has been organized regularly since 2001. The Bolimov Nature Preserve is a protected area in central Poland, situated between two agglomerations: capital city Warsaw to the East and industrial city Lodz to the West. It was established to protect an unique ecosystem on the Rawka River banks from human activity and harmful external factors. Pine tree forests, small streams, wetlands, glades are another elements of the park scenery. Walks on the park's trails are a great opportunity to see unique species of flora (more than 40 protected species and many endangered species on verge of extinction) and fauna. For teachers and students the Bolimov Nature Preserve offers educational lessons and events. The main activity is participation of students and teachers in group walk along trails of the park using various tools of orientation: maps, compasses and GPS. Along the paths they learn recognition of forms of terrain, identification of living species (using flora&fauna guides, magnifying glasses), measuring components of weather (using weather atlases, thermometers, anemometers) as well as preparation of soil profile. A survey is conducted after each such program. A statistical analysis of the survey data reveals that each year more and more students representing all levels of education from primary to upper secondary levels and their teachers are involved

  5. Nanocelluloses from jute fibers and their nanocomposites with natural rubber: Preparation and characterization.

    Science.gov (United States)

    Thomas, Martin George; Abraham, Eldho; Jyotishkumar, P; Maria, Hanna J; Pothen, Laly A; Thomas, Sabu

    2015-11-01

    Nanocellulose fibers having an average diameter of 50nm were isolated from raw jute fibers by steam explosion process. The isolation of nanocellulose from jute fibers by this extraction process is proved by SEM, XRD, FTIR, birefringence and TEM characterizations. This nanocellulose was used as the reinforcing agent in natural rubber (NR) latex along with crosslinking agents to prepare crosslinked nanocomposite films. The effects of nanocellulose loading on the morphology and mechanics of the nanocomposites have been carefully analyzed. Significant improvements in the Young's modulus and tensile strength of the nanocomposite were observed because of the reinforcing ability of the nanocellulose in the rubber matrix. A mechanism is suggested for the formation of the Zn-cellulose complex. The three-dimensional network of cellulose nanofibers (cellulose/cellulose network and Zn/cellulose network) in the NR matrix plays a major role in improving the properties of the crosslinked nanocomposites.

  6. Universal Nature-inspired Coatings for Preparing Non-charging Surfaces.

    Science.gov (United States)

    Fang, Yan; Gonuguntla, Spandhana; Soh, Siowling

    2017-08-18

    Static charge generated by contact electrification on surfaces can lead to many undesirable consequences, such as a reduction in the efficiency of manufacturing processes, damage to equipment, and explosions. However, it is extremely challenging to avoid contact electrification because it is ubiquitous - almost all types of materials charge on contact. Here, we coated materials with naturally-occurring polydopamine (PDA) and tannic acid (TA) for preparing non-charging surfaces. Importantly, these coatings are very versatile and can be coated on a wide range of materials, including metals, inorganic materials, semiconductors, and polymers. Once coated, the amount of charge generated was found to reduce dramatically at different humidities. The reduction in charge may be due to the radical-scavenging property of PDA and TA. This simple general approach is ideal for coating the vast variety of materials that need to resist charging by contact electrification.

  7. Preparation and Structural Characterization of Hydroxylethyl Methacrylate Grafted Natural Rubber Latex

    Directory of Open Access Journals (Sweden)

    Feiyun Wei

    2014-06-01

    Full Text Available The graft copolymer with semi-interpenetrating polymer networks (semi-IPNs from 2-hydroxyethyl methacrylate (HEMA and natural rubber (NR latex was prepared using cumene hydroperoxide and tetraethylene pentamine redox initiator system. The changes of grafting ratios and grafting efficiency with the reaction time and temperature, the concentration of crosslinking agent, initiator and monomer were investigated. The appropriate amounts of crosslinking agent (0.1phr, initiator (0.2phr and monomer (20phr and the optimum reaction conditions of 16ºC×8h were determined. The swelling temperature and times of monomers against NR latex particles were found to be significant for the grafting copolymerization and the appropriate swelling conditions were 16ºC×20h. The water contact angle measurement and platelet adhesion evaluation indicated that the hydrophilicity and blood compatibility of NR latex could be improved by grafting copolymerization with HEMA.

  8. Adsorption of benzaldehyde at the surface of ice, studied by experimental method and computer simulation.

    Science.gov (United States)

    Petitjean, Mélanie; Hantal, György; Chauvin, Coline; Mirabel, Philippe; Le Calvé, Stéphane; Hoang, Paul N M; Picaud, Sylvain; Jedlovszky, Pál

    2010-06-15

    Adsorption study of benzaldehyde on ice surfaces is performed by combining experimental and theoretical approaches. The experiments are conducted over the temperature range 233-253 K using a coated wall flow tube coupled to a mass spectrometric detector. Besides the experimental way, the adsorption isotherm is also determined by performing a set of grand canonical Monte Carlo simulations at 233 K. The experimental and calculated adsorption isotherms show a very good agreement within the corresponding errors. Besides, both experimental and theoretical studies permit us to derive the enthalpy of adsorption of benzaldehyde on ice surfaces DeltaH(ads), which are in excellent agreement: DeltaH(ads) = -61.4 +/- 9.7 kJ/mol (experimental) and DeltaH(ads) = -59.4 +/- 5.1 kJ/mol (simulation). The obtained results indicate a much stronger ability of benzaldehyde of being adsorbed at the surface of ice than that of small aliphatic aldehydes, such as formaldehyde or acetaldehyde. At low surface coverages the adsorbed molecules exclusively lie parallel with the ice surface. With increasing surface coverage, however, the increasing competition of the adsorbed molecules for the surface area to be occupied leads to the appearance of two different perpendicular orientations relative to the surface. In the first orientation, the benzaldehyde molecule turns its aldehyde group toward the ice phase, and, similarly to the molecules in the lying orientation, forms a hydrogen bond with a surface water molecule. In the other perpendicular orientation the aldehyde group turns to the vapor phase, and its O atom interacts with the delocalized pi system of the benzene ring of a nearby lying benzaldehyde molecule of the second molecular layer. In accordance with this observed scenario, the saturated adsorption layer, being stable in a roughly 1 kJ/mol broad range of chemical potentials, contains, besides the first molecular layer, also traces of the second molecular layer of adsorbed

  9. Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation

    Science.gov (United States)

    2014-01-01

    The popularity of natural bodybuilding is increasing; however, evidence-based recommendations for it are lacking. This paper reviewed the scientific literature relevant to competition preparation on nutrition and supplementation, resulting in the following recommendations. Caloric intake should be set at a level that results in bodyweight losses of approximately 0.5 to 1%/wk to maximize muscle retention. Within this caloric intake, most but not all bodybuilders will respond best to consuming 2.3-3.1 g/kg of lean body mass per day of protein, 15-30% of calories from fat, and the reminder of calories from carbohydrate. Eating three to six meals per day with a meal containing 0.4-0.5 g/kg bodyweight of protein prior and subsequent to resistance training likely maximizes any theoretical benefits of nutrient timing and frequency. However, alterations in nutrient timing and frequency appear to have little effect on fat loss or lean mass retention. Among popular supplements, creatine monohydrate, caffeine and beta-alanine appear to have beneficial effects relevant to contest preparation, however others do not or warrant further study. The practice of dehydration and electrolyte manipulation in the final days and hours prior to competition can be dangerous, and may not improve appearance. Increasing carbohydrate intake at the end of preparation has a theoretical rationale to improve appearance, however it is understudied. Thus, if carbohydrate loading is pursued it should be practiced prior to competition and its benefit assessed individually. Finally, competitors should be aware of the increased risk of developing eating and body image disorders in aesthetic sport and therefore should have access to the appropriate mental health professionals. PMID:24864135

  10. Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation.

    Science.gov (United States)

    Helms, Eric R; Aragon, Alan A; Fitschen, Peter J

    2014-01-01

    The popularity of natural bodybuilding is increasing; however, evidence-based recommendations for it are lacking. This paper reviewed the scientific literature relevant to competition preparation on nutrition and supplementation, resulting in the following recommendations. Caloric intake should be set at a level that results in bodyweight losses of approximately 0.5 to 1%/wk to maximize muscle retention. Within this caloric intake, most but not all bodybuilders will respond best to consuming 2.3-3.1 g/kg of lean body mass per day of protein, 15-30% of calories from fat, and the reminder of calories from carbohydrate. Eating three to six meals per day with a meal containing 0.4-0.5 g/kg bodyweight of protein prior and subsequent to resistance training likely maximizes any theoretical benefits of nutrient timing and frequency. However, alterations in nutrient timing and frequency appear to have little effect on fat loss or lean mass retention. Among popular supplements, creatine monohydrate, caffeine and beta-alanine appear to have beneficial effects relevant to contest preparation, however others do not or warrant further study. The practice of dehydration and electrolyte manipulation in the final days and hours prior to competition can be dangerous, and may not improve appearance. Increasing carbohydrate intake at the end of preparation has a theoretical rationale to improve appearance, however it is understudied. Thus, if carbohydrate loading is pursued it should be practiced prior to competition and its benefit assessed individually. Finally, competitors should be aware of the increased risk of developing eating and body image disorders in aesthetic sport and therefore should have access to the appropriate mental health professionals.

  11. Preparation and characterization of potato starch nanocrystal reinforced natural rubber nanocomposites.

    Science.gov (United States)

    Rajisha, K R; Maria, H J; Pothan, L A; Ahmad, Zakiah; Thomas, S

    2014-06-01

    Potato starch nanocrystals were found to serve as an effective reinforcing agent for natural rubber (NR). Starch nanocrystals were obtained by the sulfuric acid hydrolysis of potato starch granules. After mixing the latex and the starch nanocrystals, the resulting aqueous suspension was cast into film by solvent evaporation method. The composite samples were successfully prepared by varying filler loadings, using a colloidal suspension of starch nanocrystals and NR latex. The morphology of the nanocomposite prepared was analyzed by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). FESEM analysis revealed the size and shape of the crystal and their homogeneous dispersion in the composites. The crystallinity of the nanocomposites was studied using XRD analysis which indicated an overall increase in crystallinity with filler content. The mechanical properties of the nanocomposites such as stress-strain behavior, tensile strength, tensile modulus and elongation at break were measured according to ASTM standards. The tensile strength and modulus of the composites were found to improve tremendously with increasing nanocrystal content. This dramatic increase observed can be attributed to the formation of starch nanocrystal network. This network immobilizes the polymer chains leading to an increase in the modulus and other mechanical properties.

  12. Preparation of sulfonic acid-containing rubbers from natural rubber vulcanizates

    Science.gov (United States)

    Poonsawat, Worapong; Poompradub, Sirilux; Ngamcharussrivichai, Chawalit

    2014-06-01

    In this work, a series of sulfonic acid-containing rubbers were prepared by aqueous phase oxidation of natural rubber vulcanizates in the presence of hydrogen peroxide (H2O2) and formic acid (HCOOH). The starting vulcanizates were neatly prepared via an efficient vulcanization (EV) system by varying mass ratio of N-cyclohexyl-2-benzothiazole sulfonamide (CBS), as an accelerator, to sulfur. The oxidation conditions were controlled at the molar ratio of H2O2: HCOOH = 1:1, the concentration of H2O2 = 15 wt.%, the temperature = 50 °C, and the reaction time = 3 h. The rubber materials before and after the oxidation were characterized for their physicochemical properties by using Fourier transform infrared spectroscopy, bomb calorimetry, acid-base titration and swelling measurements. The results indicated the presence of sulfonic acid group in the oxidized rubbers, generated by the oxidative cleaves of sulfide crosslinks in the rubber vulcanizates. The oxidation decreased the sulfur content of the rubber in which the level of sulfur loss was determined by the CBS/sulfur ratio. Moreover, the acidity of the oxidized products was correlated with the amount of sulfur remaining.

  13. Facile Synthesis of Benzaldehyde-Functionalized Ionic Liquids and Their Flexible Functional Group Transformations

    Directory of Open Access Journals (Sweden)

    Qiang Huang

    2012-01-01

    Full Text Available Three benzaldehyde-functionalized ionic liquids were readily synthesized by quaternization of N-alkylimidazole with benzaldehyde-functionalized alkyl bromides under microwave irradiation in good yield. These aldehyde-functionalized ionic liquids could easily be oxidized in the presence of H2O2/KOH or be reduced by NaBH4 leading to the formation of the corresponding carboxyl-functionalized ionic liquids or benzylic alcohol-functionalized ionic liquids. In addition, the condensations of these functionalized ones with hydrazine hydrate and with aniline under reductive amination conditions were demonstrated.

  14. Preparation and characterization of regenerated cellulose membranes from natural cotton fiber

    Directory of Open Access Journals (Sweden)

    Yanjuan CAO

    2015-06-01

    Full Text Available A series of organic solutions with different cellulose concentrations are prepared by dissolving natural cotton fibers in lithium chloride/dimethyl acetamide (LiCl/DMAC solvent system after the activation of cotton fibers. Under different coagulating bath, the regenerated cellulose membranes are formed in two kinds of coagulation baths, and two coating methods including high-speed spin technique (KW-4A spin coating machine and low-speed scraping (AFA-Ⅱ Film Applicator are selected in this paper. The macromolecular structure, mechanical properties, crystallinity, thermal stability and wetting property of the regenerated cellulose membrane are characterized by Scanning Electron Microscope(SEM, Fourier Transform Infrared Spectroscopy (FT-IR,X-ray diffraction (XRD, Thermogravimetric analysis (TG and contacting angle tester. The effects of mass fraction, coagulation bath type, membrane forming process on the regenerated membrane properties are investigated. Experimental results show that the performance of regenerated cellulose membrane is relatively excellent under the condition of using the KW-4A high-speed spin method, water coagulation bath, and when mass fraction of cellulose is 3.5%. The crystallinity of the regenerated cellulose membrane changes a lot compared with natural cotton fibers. The variation trend of thermal stability is similar with that of cotton fiber. But thermal stability is reduced to some degree, while the wetting ability is improved obviously.

  15. Preparation, Characterization and Methylene Blue Dye Adsorption Ability of Acid Activated-Natural Zeolite

    Science.gov (United States)

    Saputra, O. A.; Prameswari, M. D.; Kinanti, V. T. D.; Mayasari, O. D.; Sutarni, Y. D.; Apriany, K.; Lestari, W. W.

    2017-02-01

    The aim of this research was to prepare an acid-activated natural zeolite (Ac-Zeo) as a low-cost adsorbent material and to investigate their ability on methylene blue dye removal in aqueous solution. The natural zeolite was activated using hydrochloric acid and the final product was characterized using Fourier transform infra-red (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The adsorption process was carried out using the batch method. Some parameters like pH condition, contact time and varied dye initial concentration were studied to determine the adsorption ability of Ac-Zeo. In this study, kinetic adsorption was evaluated using pseudo-second order model approach and found that the kinetic adsorption rate constanta (k) and adsorption capacity at equilibrium are 0.1872 mg.g-1.min-1 and 14.94 mg.g-1, respectively. Moreover, Langmuir, Freundlich, and Dubinin–Kaganer–Radushkevich isotherm adsorption models as well as sorption mechanism were studied in this research.

  16. Natural rubber latex blended polystyrene emulsion for dipping products: preparation and properties

    Directory of Open Access Journals (Sweden)

    Kovuttikulrangsie, S.

    2004-05-01

    Full Text Available Deproteinized natural rubber latex (DPNR was prepared using KAO protease enzyme to digest proteins from natural rubber low ammonia concentrated latex (NR-LA. Polystyrene latex (PS was synthesized by emulsion polymerization technique for blending with natural rubber. The maximum fraction of PS blended NR-LA or DPNR used to obtain a homogenous film was 20% w/w. The 300% modulus of PS blended NR film was increased before and after aging at 100ºC for 22 hrs. The tensile strength and elongation at break were increased at NR/PS = 95/5 w/w and tended to decrease as PS blended fraction increased. DPNR films had a lower friction coefficient than NR-LA films. PS blended NR-LA or DPNR would decrease the friction coefficient of films. The rubber-surfaced friction is reduced. The extractable protein of NR-LA film was higher than 200 μg/g whereas that of DPNR film was lower than 50 μg/g. PS blended NR-LA and DPNR could reduce the extractable protein to less than 60 μg/g and 30μg/g, respectively. The physical properties of PS blended NR-LA met ASTM D3577 and ASTM D3578 standards for dipping products of surgical gloves and examination gloves at the maximum fraction of PS 15% w/w and 20% w/w, respectively, whereas PS blended DPNR only met ASTM D3577 standard at the maximum fraction of PS < 5% w/w.

  17. Equilibrium CO2 adsorption on zeolite 13X prepared from natural clays

    Science.gov (United States)

    Garshasbi, Vahid; Jahangiri, Mansour; Anbia, Mansoor

    2017-01-01

    Zeolite 13X was successfully synthesized by hydrothermal treatment using natural clays extracted from Iranian resources. The preliminary natural materials and the final zeolite 13X samples were characterized by X-ray Diffraction (XRD), Fourier-Transfer Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM) and N2 adsorption-desorption isotherm. The effects of various factors such as NaOH addition amount and aging time on the crystalline products were studied during the synthesis process. The optimum conditions related to the synthesis of zeolite 13X were set. Accordingly, NaOH concentration was equal to 4 M. It was further crystallized at 65 °C for 72 h after its homogenization by agitation at room temperature for 120 h. In this study, the zeolite 13X prepared from natural kaolin (13X-K) showed a high BET surface area of 591 m2/g with higher micropore volume (0.250 cm3/g) than other materials. Adsorption equilibrium isotherms of CO2 were investigated using a static, volumetric method. In addition, pressures for the pure component data extended up to 20 bar. The adsorption equilibrium data of CO2 was fitted to Langmuir, Freundlich, Lamgmuir-Freundlich, Toth and BET isotherm models. It was found that the Langmuir-Freundlich model was more suitable than other models for CO2 description. The results showed that the synthetic zeolite has higher equilibrium selectivity for CO2. Also, the CO2 uptake by zeolite 13X-K was equal to 6.9 mmol/g.

  18. Magnesium salts as compounds of the preparation of magnesium oxide from Tunisian natural brines

    Directory of Open Access Journals (Sweden)

    Behij Souheil

    2013-01-01

    Full Text Available Magnesium oxide is one of the most important magnesium compounds used in industry. The production of MgO is often done from calcined magnesium carbonate or from natural magnesium saline solutions (sea water and brines. In the case of these solutions, magnesium oxide is precipitated after the addition of a strong base (eg. Ammonia. Magnesium hydroxide is calcined after its separation from the excess resulting from the strong base through filtration. Thus, magnesia qualities may differ depending on several physical parameters and particularly on the nature of the compound. Consequently, two different compounds were selected: magnesium chloride and magnesium sulphate which can be recovered from Tunisian natural brines. Three physical factors were considered: calcination temperatures, precipitation temperatures and calcination time of Mg(OH2. The decomposition of Mg(OH2 was investigated by DTA/TGA. Mass losses vary in the range (23.0%-29.9%. Starting decomposition temperatures are between 362°C and 385°C. The MgO produced from MgSO4 under 1000°C within 48 hours of calcination time and with 40°C as a reaction temperature for Mg(OH2 shows a good crystallinity and is of a cristallyte size of 86.3 nm and has a specific surface area equal to 16.87 m2g-1. Finally, morphological differences between MgO agglomerates at different temperatures were observed by SEM. Consequently, magnesium sulphate as precursor for preparing MgO is selected.

  19. Preparation

    Directory of Open Access Journals (Sweden)

    M.M. Dardir

    2014-03-01

    Full Text Available Some hexanamide-mono and di-linoleniate esters were prepared by the reaction of linolenic acid and hexanamide (derived from the reaction of hexanoic acid and diethanolamine. The chemical structure for the newly prepared hexanamide-mono and di-linoleniate esters were elucidated using elemental analysis, (FTIR, H 1NMR and chemical ionization mass spectra (CI/Ms spectroscopic techniques. The results of the spectroscopic analysis indicated that they were prepared through the right method and they have high purity. The new prepared esters have high biodegradability and lower toxicity (environmentally friendly so they were evaluated as a synthetic-based mud (ester-based mud for oil-well drilling fluids. The evaluation included study of the rheological properties, filtration and thermal properties of the ester based-muds formulated with the newly prepared esters compared to the reference commercial synthetic-based mud.

  20. Reinforcement of natural rubber latex with silica modified by cerium oxide:preparation and properties

    Institute of Scientific and Technical Information of China (English)

    张福全; 廖禄生; 王永周; 汪月琼; 黄红海; 李普旺; 彭政; 曾日中

    2016-01-01

    Variable masses of nano cerium oxide (CeO2) were added into nano silica (SiO2) to prepare the well-dispersed SiO2-CeO2 suspension (SiO2-CeO2), cetyltrimethyl ammonium bromide (CTAB) was used to adjust the compatibility of SiO2-CeO2 with rubber matrix, then SiO2-CeO2 modified by CTAB and curing formulas were mixed with fresh natural rubber (NR) latex to prepare NR/SiO2-CeO2 nanocomposites that contained 0–10 parts of CeO2 by a new emulsion compounding method. The morphologies, cure characteristics, mechanical properties and thermal-oxidative stability of NR/SiO2-CeO2 nanocomposites were investigated. The re-sults revealed that the presence of CeO2 in NR/SiO2-CeO2nanocomposites was favorable for enhancing the interaction between NR matrix and fillers, helped to get smaller SiO2-CeO2 particles with narrower particle size distribution, further improved the crosslink densities and mechanical properties of NR/SiO2-CeO2 nanocomposites vulcanizates. Meanwhile, the addition of CeO2 increased the active energy at least 4.66%, obviously improved the thermal-oxidative aging-inhibiting properties of NR/SiO2-CeO2 nanocomposites. Additionally, nanocomposites containing CeO2 promotedTg shift to high temperature direction, causing the nanocomposites featured higher tanδ at 0 ºC and lower tanδ at 60 ºC and exhibited comparable wet grip and lower rolling resistance when NR/SiO2-CeO2nano-composites were used in tire tread compound.

  1. Characterization of naturally occurring airborne diacetyl concentrations associated with the preparation and consumption of unflavored coffee

    Directory of Open Access Journals (Sweden)

    Jennifer S. Pierce

    2015-01-01

    Full Text Available Diacetyl, a suspected cause of respiratory disorders in some food and flavorings manufacturing workers, is also a natural component of roasted coffee. We characterized diacetyl exposures that would plausibly occur in a small coffee shop during the preparation and consumption of unflavored coffee. Personal (long- and short-term and area (long-term samples were collected while a barista ground whole coffee beans, and brewed and poured coffee into cups. Simultaneously, long-term personal samples were collected as two participants, the customers, drank one cup of coffee each per h. Air sampling and analyses were conducted in accordance with OSHA Method 1012. Diacetyl was detected in all long-term samples. The long-term concentrations for the barista and area samples were similar, and ranged from 0.013–0.016 ppm; long-term concentrations for the customers were slightly lower and ranged from 0.010–0.014 ppm. Short-term concentrations ranged from below the limit of detection (<0.0047 ppm–0.016 ppm. Mean estimated 8 h time-weighted average (8 h TWA exposures for the barista ranged from 0.007–0.013 ppm; these values exceed recommended 8 h TWA occupational exposure limits (OELs for diacetyl and are comparable to long-term personal measurements collected in various food and beverage production facilities. The concentrations measured based on area sampling were comparable to those measured in the breathing zone of the barista, thus exceedances of the recommended OELs may also occur for coffee shop workers who do not personally prepare coffee (e.g., cashier, sanitation/maintenance. These findings suggest that the practicality and scientific basis of the recommended OELs for diacetyl merit further consideration.

  2. A theoretical study of benzaldehyde derivatives as tyrosinase inhibitors using Ab initio calculated NQCC parameters

    Directory of Open Access Journals (Sweden)

    Marjan Rafiee

    2015-09-01

    Full Text Available Tyrosinase is a multifunctional copper-containing enzyme. It can catalyze two distinct reactions of melanin synthesis and benzaldehyde derivatives, which are potential tyrosinase inhibitors. To find the relationships between charge distributions of benzaldehyde and their pharmaceutical behavior, the present study aimed at investigating nuclear quadrupole coupling constants of quadrupolare nuclei in the functional benzaldehyde group and calculating some its derivatives. In addition, the differences between the electronic structures of various derivatives of this depigmenting drug were examined. All ab initio calculations were carried out using Gaussian 03. The results predicted benzaldehyde derivatives to be bicentral inhibitors; nevertheless, the oxygen or hydrogen contents of the aldehyde group were not found to be the only active sites. Furthermore with the presence of the aldehyde group, the terminal methoxy group in C4 was found to contribute to tyrosinase inhibitory activities. In addition, an oxygen atom with high charge density in the side chain was found to play an important role in its inhibitory effect.

  3. Chiral diethanolamines and their lithium alcoholates as catalysts in the enantioselective alkylation of benzaldehyde by diethylzinc

    NARCIS (Netherlands)

    De Vries, E.F.J.; Brussee, J.; Knise, Chris G.; Van Der Gen, A.

    1993-01-01

    The enantioselective alkylation of benzaldehyde by diethylzinc in the presence of catalytic amounts of bis-erythro diethanolamines and their lithium alcoholates was studied. The extent of asymmetric induction was found to depend strongly upon subtle changes in the structure of the catalyst used.

  4. Catalytic Enantioselective Alkylation of Benzaldehyde with Diethylzinc Using Chiral Nonracemic (Thio)-phosphoramidates

    NARCIS (Netherlands)

    Hulst, Ron; Heres, Hero; Fitzpatrick, Kevin; Peper, Nathalie C.M.W.; Kellogg, Richard M.

    1996-01-01

    Two chiral nonracemic γ-amino alcohols, ephedrine thiol and the corresponding (thio)-phosphoramidates have been examined as catalysts for the enantioselective alkylation of benzaldehyde by diethylzinc. Addition of titanium tetraisopropoxide increases the yield as well as the enantioselectivity; 1-ph

  5. OPTIMIZATION OF TIME REACTION AND HYDROXIDE ION CONCENTRATION ON FLAVONOID SYNTHESIS FROM BENZALDEHYDE AND ITS DERIVATIVES

    Directory of Open Access Journals (Sweden)

    Sri Handayani

    2010-06-01

    Full Text Available The aim of this research is to determine the optimum time of reaction and concentration of hydroxide ion on chalcone, 4-methoxychalcone and 3,4-dimethoxychalcone synthesis. Chalcone and its derivatives were synthesized by dissolving KOH in ethanol followed by dropwise addition of acetophenone and benzaldehyde. Then, the mixture was stirred for several hours. Three benzaldehydes has been used, i.e : benzaldehyde, p-anysaldehyde and veratraldehyde. The time of reaction was varied for, 12, 18, 24, 30 and 36 hours. Furthermore, on the optimum reaction time for each benzaldehyde the hydroxyl ion concentration was varied from 5,7,9,11 and 13%(w/v. The results of this research suggested that the optimum time of chalchone synthesis was 12 hours, while, 4-methoxychalcone and 3,4-dimethoxychalcone were 30 hours. The optimum concentration of hydroxide ion of chalcone synthesis was 13% and for 4-methoxychalcone and 3,4-dimethoxychalcone were 11%. Keywords: Chalcone synthesis, time of reaction, hydroxide ion concentration.

  6. Regioselective Protection of the 4-Hydroxyl of 3,4-Dihydroxy-benzaldehyde

    Directory of Open Access Journals (Sweden)

    Randy R. Spaetzel

    2003-09-01

    Full Text Available The regioselective protection of the 4-hydroxyl group of 3,4-dihydroxy-benzaldehyde was accomplished with seven different protecting groups (benzyl, p-methoxybenzyl, o-nitrobenzyl, 2,6-dichlorobenzyl, 3,4-dichlorobenzyl, vinyl and propargyl in yields ranging between 67-75%.

  7. A theoretical study of benzaldehyde derivatives as tyrosinase inhibitors using Ab initio calculated NQCC parameters

    Science.gov (United States)

    Rafiee, Marjan; Javaheri, Masoumeh

    2015-01-01

    Tyrosinase is a multifunctional copper-containing enzyme. It can catalyze two distinct reactions of melanin synthesis and benzaldehyde derivatives, which are potential tyrosinase inhibitors. To find the relationships between charge distributions of benzaldehyde and their pharmaceutical behavior, the present study aimed at investigating nuclear quadrupole coupling constants of quadrupolare nuclei in the functional benzaldehyde group and calculating some its derivatives. In addition, the differences between the electronic structures of various derivatives of this depigmenting drug were examined. All ab initio calculations were carried out using Gaussian 03. The results predicted benzaldehyde derivatives to be bicentral inhibitors; nevertheless, the oxygen or hydrogen contents of the aldehyde group were not found to be the only active sites. Furthermore with the presence of the aldehyde group, the terminal methoxy group in C4 was found to contribute to tyrosinase inhibitory activities. In addition, an oxygen atom with high charge density in the side chain was found to play an important role in its inhibitory effect. PMID:27844007

  8. Serotonin Mediates a Learned Increase in Attraction to High Concentrations of Benzaldehyde in Aged "C. elegans"

    Science.gov (United States)

    Tsui, David; van der Kooy, Derek

    2008-01-01

    We utilized olfactory-mediated chemotaxis in "Caenorhabditis elegans" to examine the effect of aging on information processing and animal behavior. Wild-type (N2) young adults (day 4) initially approach and eventually avoid a point source of benzaldehyde. Aged adult animals (day 7) showed a stronger initial approach and a delayed avoidance to…

  9. Biotransformation of benzaldehyde into (R)-phenylacetylcarbinol by filamentous fungi or their extracts.

    Science.gov (United States)

    Rosche, B; Sandford, V; Breuer, M; Hauer, B; Rogers, P

    2001-10-01

    Extracts of 14 filamentous fungi were examined regarding their potential for production of (R)-phenylacetylcarbinol [(R)-PAC], which is the chiral precursor in the manufacture of the pharmaceuticals ephedrine and pseudoephedrine. Benzaldehyde and pyruvate were transformed at a scale of 1.2 ml into PAC by cell-free extracts of all selected strains, covering the broad taxonomic spectrum of Ascomycota, Zygomycota and Basidiomycota. Highest final PAC concentrations were obtained with the extracts of Rhizopus javanicus and Fusarium sp. [78-84 mM (11.7-12.6 g/l) PAC within 20 h from initial substrate concentrations of 100 mM benzaldehyde and 150 mM pyruvate]. (R)-PAC was in about 90-93% enantiomeric excess. Rhizopus javanicus had the advantage of faster growth than Fusarium sp. Rhizopus javanicus mycelia were used as an example in a biotransformation process based on whole cells and benzaldehyde and glucose as substrates. The substrate pyruvate was generated through the fungal fermentation of glucose. Only 19 mM PAC (2.9 g/l) were produced within 8 h from 80 mM benzaldehyde. with evidence of significant benzyl alcohol production.

  10. Deoxygenation of benzoic acid on metal oxides. I. The selective pathway to benzaldehyde

    NARCIS (Netherlands)

    Lange, de M.W.; Ommen, van J.G.; Lefferts, L.

    2001-01-01

    The mechanism of the selective deoxygenation of benzoic acid to benzaldehyde was studied on ZnO and ZrO2. The results show conclusively that the reaction proceeds as a reverse type of Mars and van Krevelen mechanism consisting of two steps: hydrogen activates the oxide by reduction resulting in the

  11. Catalytic Enantioselective Alkylation of Benzaldehyde with Diethylzinc Using Chiral Nonracemic (Thio)-phosphoramidates

    NARCIS (Netherlands)

    Hulst, Ron; Heres, Hero; Fitzpatrick, Kevin; Peper, Nathalie C.M.W.; Kellogg, Richard M.

    1996-01-01

    Two chiral nonracemic γ-amino alcohols, ephedrine thiol and the corresponding (thio)-phosphoramidates have been examined as catalysts for the enantioselective alkylation of benzaldehyde by diethylzinc. Addition of titanium tetraisopropoxide increases the yield as well as the enantioselectivity; 1-ph

  12. Antifungal activity of redox-active benzaldehydes that target cellular antioxidation

    Science.gov (United States)

    Many pathogenic fungi are becoming resistant to currently available drugs. Disruption of cellular antioxidation systems should be an effective method for control of fungal pathogens. Such disruption can be achieved with redox-active compounds. The aim of this study was to identify benzaldehydes that...

  13. Chemo-sensitization of fungal pathogens to antimicrobial agents using benzaldehyde analogs

    Science.gov (United States)

    Activity of conventional antifungal agents, fludioxonil, strobilurin and antimycinA, which target the oxidative and osmotic stress response systems, was elevated by co-application of certain analogs of benzaldehyde. Fungal tolerance to 2,3-dihydroxybenzaldehyde or 2,3-dihydroxybenzoic acid was foun...

  14. Rheological profiling of organogels prepared at critical gelling concentrations of natural waxes in a triacylglycerol solvent.

    Science.gov (United States)

    Patel, Ashok R; Babaahmadi, Mehrnoosh; Lesaffer, Ans; Dewettinck, Koen

    2015-05-20

    The aim of this study was to use a detailed rheological characterization to gain new insights into the gelation behavior of natural waxes. To make a comprehensive case, six natural waxes (differing in the relative proportion of chemical components: hydrocarbons, fatty alcohols, fatty acids, and wax esters) were selected as organogelators to gel high-oleic sunflower oil. Flow and dynamic rheological properties of organogels prepared at critical gelling concentrations (Cg) of waxes were studied and compared using drag (stress ramp and steady flow) and oscillatory shear (stress and frequency sweeps) tests. Although, none of the organogels satisfied the rheological definition of a "strong gel" (G″/G' (ω) ≤ 0.1), on comparing the samples, the strongest gel (highest critical stress and dynamic, apparent, and static yield stresses) was obtained not with wax containing the highest proportion of wax esters alone (sunflower wax, SFW) but with wax containing wax esters along with a higher proportion of fatty alcohols (carnauba wax, CRW) although at a comparatively higher Cg (4%wt for latter compared to 0.5%wt for former). As expected, gel formation by waxes containing a high proportion of lower melting fatty acids (berry, BW, and fruit wax, FW) required a comparatively higher Cg (6 and 7%wt, respectively), and in addition, these gels showed the lowest values for plateau elastic modulus (G'LVR) and a prominent crossover point at higher frequency. The gelation temperatures (TG'=G″) for all the studied gels were lower than room temperature, except for SFW and CRW. The yielding-type behavior of gels was evident, with most gels showing strong shear sensitivity and a weak thixotropic recovery. The rheological behavior was combined with the results of thermal analysis and microstructure studies (optical, polarized, and cryo-scanning electron microscopy) to explain the gelation properties of these waxes.

  15. Preparation and characterization of chitosan-natural nano hydroxyapatite-fucoidan nanocomposites for bone tissue engineering.

    Science.gov (United States)

    Lowe, Baboucarr; Venkatesan, Jayachandran; Anil, Sukumaran; Shim, Min Suk; Kim, Se-Kwon

    2016-12-01

    Solid three dimensional (3D) composite scaffolds for bone tissue engineering were prepared using the freeze-drying method. The scaffolds were composed of chitosan, natural nano-hydroxyapatite (nHA) and fucoidan in the following combinations: chitosan, chitosan-fucoidan, chitosan-nHA, and chitosan-nHA-fucoidan. Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), and optical microscopy (OM) were used to determine the physiochemical constituents and the morphology of the scaffolds. The addition of nHA into the chitosan-fucoidan composite scaffold reduced the water uptake and water retention. FT-IR analysis confirmed the presence of a phosphate group in the chitosan-nHA-fucoidan scaffold. This group is present because of the presence of nHA (isolated via alkaline hydrolysis from salmon fish bones). Microscopic results indicated that the dispersion of nHA and fucoidan in the chitosan matrix was uniform with a pore size of 10-400μm. The composite demonstrated a suitable micro architecture for cell growth and nutrient supplementation. This compatibility was further elucidated in vitro using periosteum-derived mesenchymal stem cells (PMSCs). The cells demonstrated high biocompatibility and excellent mineralization for the chitosan-nHA-fucoidan scaffold. We believe that a chitosan-nHA-fucoidan composite is a promising biomaterial for the scaffold that can be used for bone tissue regeneration.

  16. Physical and Degradable Properties of Mulching Films Prepared from Natural Fibers and Biodegradable Polymers

    Directory of Open Access Journals (Sweden)

    Zhijian Tan

    2016-05-01

    Full Text Available The use of plastic film in agriculture has the serious drawback of producing vast quantities of waste. In this work, films were prepared from natural fibers and biodegradable polymers as potential substitutes for the conventional non-biodegradable plastic film used as mulching material in agricultural production. The physical properties (e.g., mechanical properties, heat preservation, water permeability, and photopermeability and degradation characteristics (evaluated by micro-organic culture testing and soil burial testing of the films were studied in both laboratory and field tests. The experimental results indicated that these fiber/polymer films exhibited favorable physical properties that were sufficient for use in mulching film applications. Moreover, the degradation degree of the three tested films decreased in the following order: fiber/starch (ST film > fiber/poly(vinyl alcohol (PVA film > fiber/polyacrylate (PA film. The fiber/starch and fiber/PVA films were made from completely biodegradable materials and demonstrated the potential to substitute non-biodegradable films.

  17. Search for Antiprotozoal Activity in Herbal Medicinal Preparations; New Natural Leads against Neglected Tropical Diseases

    Directory of Open Access Journals (Sweden)

    Núria Llurba Montesino

    2015-08-01

    Full Text Available Sleeping sickness, Chagas disease, Leishmaniasis, and Malaria are infectious diseases caused by unicellular eukaryotic parasites (“protozoans”. The three first mentioned are classified as Neglected Tropical Diseases (NTDs by the World Health Organization and together threaten more than one billion lives worldwide. Due to the lack of research interest and the high increase of resistance against the existing treatments, the search for effective and safe new therapies is urgently required. In view of the large tradition of natural products as sources against infectious diseases [1,2], the aim of the present study is to investigate the potential of legally approved and marketed herbal medicinal products (HMPs as antiprotozoal agents. Fifty-eight extracts from 53 HMPs on the German market were tested by a Multiple-Target-Screening (MTS against parasites of the genera Leishmania, Trypanosoma, and Plasmodium. Sixteen HMPs showed in vitro activity against at least one of the pathogens (IC50 < 10 µg/mL. Six extracts from preparations of Salvia, Valeriana, Hypericum, Silybum, Arnica, and Curcuma exhibited high activity (IC50 < 2.5 µg/mL. They were analytically characterized by UHPLC/ESI-QqTOF-MSMS and the activity-guided fractionation of the extracts with the aim to isolate and identify the active compounds is in progress.

  18. Effect of manganese and potassium addition on CeO2-Al2O3 catalyst for hydrogenation of benzoic acid to benzaldehyde

    Institute of Scientific and Technical Information of China (English)

    CHENG; Dangguo; HOU; Chunyang; CHEN; Fengqiu; ZHAN; Xiaol

    2009-01-01

    A series of Mn/CeO2-Al2O3 and K/CeO2-Al2O3 catalysts for hydrogenation of benzoic acid to benzaldehyde were prepared to in-vestigate the effect of Mn, K addition on CeO2-Al2O3 catalyst. X-ray diffraction (XRD) and H2-temperature-programmed reduction (H2-TPR) results suggested that the interaction between CeO2 and MnOx enhanced the reducibility of catalysts and therefore benzoic acid conversion.The addition of K increased the number of basic number on the catalyst which leads to a high selectivity to benzaldehyde, but excessive addition imposed negative effects on the catalyst performance. A Mn-K/CeO2Al2O3 catalyst was developed and investigated in the reaction. The simul-taneous addition of Mn and K enhanced not only the catalytic activity but also the capacity to resist the coke formation over catalyst.

  19. 77 FR 3255 - Notice of Intent To Prepare an Environmental Impact Statement for the Acquisition of a Natural...

    Science.gov (United States)

    2012-01-23

    ... the areas of energy efficiency, renewable energy, toxic chemical reduction, recycling, sustainable... time, DOE does not plan to evaluate other sources of energy supply, or other means to supply natural... Doc No: 2012-1139] DEPARTMENT OF ENERGY Notice of Intent To Prepare an Environmental Impact...

  20. An efficient procedure for the preparation of natural products bearing the 2-(2-phenylethyl)chromone skeleton

    Science.gov (United States)

    Williams, Dwight A.; Smith, Cameron; Zhang, Yan

    2013-01-01

    Several 2-(2-phenylethyl)chromones have been shown to possess neuroprotective activity. However, limited synthetic methods have been disclosed to construct the 2-(2-phenylethyl)chromone skeleton. Herein we report a straightforward 3-step preparation of five naturally occurring 2-(2-phenylethyl)chromones utilizing the Claisen condensation as the key step. PMID:23935224

  1. Phytoestrogen-Rich Natural Preparation for Treatment of Climacteric Syndrome and Atherosclerosis Prevention in Perimenopausal Women.

    Science.gov (United States)

    Kirichenko, T V; Myasoedova, V A; Orekhova, V A; Ravani, A L; Nikitina, N A; Grechko, A V; Sobenin, I A; Orekhov, A N

    2017-08-01

    The present study evaluated the risks and benefits of phytoestrogen treatment in healthy perimenopausal women in relation to the dynamics of climacteric syndrome and progression of atherosclerosis. Study participants were treated with placebo or phytoestrogen-rich natural preparation Karinat based on grape (Vitis vinifera) seeds, green tea (Camellia sinensis) leaves, hop (Hunulus lupulus) cone powder and garlic (Allium sativum) powder. The dynamics of climacteric syndrome was evaluated by Kupperman Index and Utian Quality of Life Scale. Atherosclerosis progression was evaluated by measuring carotid intima-media thickness. Significant changes of climacteric syndrome's severity in both Karinat and placebo groups (p = 0.005 and p = 0.001) were obtained after 24 months of follow-up. Detailed analysis of Kupperman Index suggested that Karinat possessed a significant effect on nervousness (p = 0.010), weakness (p = 0.020) and formication (p = 0.010). A significant improvement of medical (p = 0.070) and emotional (p = 0.060) components of Kupperman Index and Utian Quality of Life Scale was also observed in Karinat group. However, difference in carotid intima-media thickness between the two groups was not statistically significant at follow-up. A slight positive effect of phytoestrogens on climacteric syndrome manifestations was demonstrated in this study. Karinat can be used for alleviation of climacteric syndrome and cardiovascular disease prevention in perimenopausal women. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  2. Bioplastic composite foam prepared from poly(lactic acid) and natural wood flour

    Science.gov (United States)

    Suwannakas, Pokkes; Petrchwattana, Nawadon; Covavisaruch, Sirijutaratana

    2016-03-01

    The major drawbacks of Poly(lactic acid) (PLA) bioplastic are its cost and brittleness. This study aims to reduce the cost by foaming PLA reinforced with wood flour. A series of PLA/ natural fiber (WF) composite was prepared by using WF of selected conifers up to 5 wt%; each composite formulation was then foamed using 2 wt% of Azodicarbonamide (ADC) as chemical foaming agent. ADC effectively reduced the density of PLA and the PLA/WF composite foam by about 45% to 0.64 g/cm3 from 1.24 g/cm3 of neat PLA and 1.26 g/cm3 of PLA/WF composites when 2 wt% ADC was applied. Mechanical behaviors in terms of compressive and impact properties were investigated. With the presence of WF, the compressive stress increased with the WF content due to the good interfacial adhesion between the PLA matrix and the WF. This was verified by microscopic observation, leading to efficient stress transfer at the interface between PLA matrix and the WF. The presence of WF raised the specific compressive modulus and strength of PLA/WF composites to around 0.94 GPa.cm3/g and 2.65 MPa.cm3/g but foaming the PLA or the PLA/WF composites led to a dramatic reduction of the compressive modulus to 0.2-0.4 GPa.cm3/g, implying that the PLA and the PLA/WF foams had become softened. This was evidently observed in the significant reduction of hardness coupled with the vast drop of stress required to compressively deform the foams.

  3. Biomolecules and Natural Medicine Preparations: Analysis of New Sources of Bioactive Compounds from Ribes and Rubus spp. Buds.

    Science.gov (United States)

    Donno, Dario; Mellano, Maria Gabriella; Cerutti, Alessandro Kim; Beccaro, Gabriele Loris

    2016-02-05

    It is well known that plants are important sources for the preparation of natural remedies as they contain many biologically active compounds. In particular, polyphenols, terpenic compounds, organic acids, and vitamins are the most widely occurring groups of phytochemicals. Some endemic species may be used for the production of herbal preparations containing phytochemicals with significant bioactivity, as antioxidant activity and anti-inflammatory capacities, and health benefits. Blackberry sprouts and blackcurrant buds are known to contain appreciable levels of bioactive compounds, including flavonols, phenolic acids, monoterpenes, vitamin C, and catechins, with several clinical effects. The aim of this research was to perform an analytical study of blackcurrant and blackberry bud-preparations, in order to identify and quantify the main biomarkers, obtaining a specific phytochemical fingerprint to evaluate the single botanical class contribution to total phytocomplex and relative bioactivity, using a High Performance Liquid Chromatograph-Diode Array Detector; the same analyses were performed both on the University laboratory and commercial preparations. Different chromatographic methods were used to determine concentrations of biomolecules in the preparations, allowing for quantification of statistically significant differences in their bioactive compound content both in the case of Ribes nigrum and Rubus cultivated varieties at different harvest stages. In blackcurrant bud-extracts the most important class was organic acids (50.98%) followed by monoterpenes (14.05%), while in blackberry preparations the main bioactive classes were catechins (50.06%) and organic acids (27.34%). Chemical, pharmaceutical and agronomic-environmental knowledge could be important for obtaining label certifications for the valorization of specific genotypes, with high clinical and pharmaceutical value: this study allowed to develop an effective tool for the natural preparation quality

  4. A nutrition and conditioning intervention for natural bodybuilding contest preparation: case study

    National Research Council Canada - National Science Library

    Robinson, Scott Lloyd; Lambeth-Mansell, Anneliese; Gillibrand, Gavin; Smith-Ryan, Abbie; Bannock, Laurent

    2015-01-01

    .... Commonly used techniques to improve physique during the preparation phase before competitions include dehydration, periods of prolonged fasting, severe caloric restriction, excessive cardiovascular...

  5. Pinacol Coupling Reaction of Benzaldehyde Mediated by TiCl3-Zn in Basic Media Under Ultrasound Irradiation

    Directory of Open Access Journals (Sweden)

    Wang Shu-Xiang

    2005-01-01

    Full Text Available Pinacol coupling of benzaldehyde mediated by TiCl3-Zn in basic media under ultrasound irradiation can lead to the corresponding pinacol rapidly. The optimum reaction condition is chosen.

  6. FT-IR spectroscopy and DFT calculation study on the solvent effects of benzaldehyde in organic solvents.

    Science.gov (United States)

    Li, Yi; Zhang, Hui; Liu, Qing

    2012-02-01

    FT-IR spectra of benzaldehyde in 11 different organic solvents were recorded and analyzed. The density functional theory (DFT) B3LYP/6-31G* method was chosen to calculate the infrared spectrum of benzaldehyde in gaseous state. The electrostatic effects of different solvents in benzaldehyde solutions were calculated using DFT with the self-consistent isodensity polarizable continuum model (SCI-PCM). Two remarkable carbonyl (C=O) peaks of benzaldehyde were observed by FT-IR in alcohol solvents, which were caused by different hydrogen bond species and explained by ab initio calculation. The results showed that the combination of SCI-PCM model and ab initio calculation could give excellent agreements with FT-IR spectra of title compound in solutions.

  7. Lignin-derived oxygenate reforming on a bimetallic surface: The reaction of benzaldehyde on Zn/Pt(111)

    Science.gov (United States)

    Shi, Daming; Vohs, John M.

    2016-08-01

    Temperature programmed desorption (TPD) and high-resolution electron energy loss spectroscopy (HREELS) were used to characterize the adsorption and reaction of benzaldehyde (C6H5CHO) on hydrogen-covered Pt(111) and Zn-modified Pt(111) surfaces. Benzaldehyde was found to interact with Pt(111) via both the phenyl ring and carbonyl of the aldehyde group. This bonding configuration facilitates unselective decomposition of the benzaldehyde to produce CO, H2, and small hydrocarbon fragments at relatively low temperatures. On the other hand, benzaldehyde was found to bond to Zn-decorated Pt(111) surface exclusively via the carbonyl group in an η2(C, O) configuration, with the phenyl ring tilted away from the surface. This configuration weakens Csbnd O bond in the carbonyl facilitating its cleavage and helps prevent hydrogenation of the phenyl ring.

  8. Feasibility of gas/solid carboligation: conversion of benzaldehyde to benzoin using thiamine diphosphate-dependent enzymes.

    Science.gov (United States)

    Mikolajek, R; Spiess, A C; Büchs, J

    2007-05-10

    A carboligation was investigated for the first time as an enzymatic gas phase reaction, where benzaldehyde was converted to benzoin using thiamine diphosphate (ThDP)-dependent enzymes, namely benzaldehyde lyase (BAL) and benzoylformate decarboxylase (BFD). The biocatalyst was immobilized per deposition on non-porous support. Some limitations of the gas/solid biocatalysis are discussed based on this carboligation and it is also demonstrated that the solid/gas system is an interesting tool for more volatile products.

  9. Model studies on the oxygen-induced formation of benzaldehyde from phenylacetaldehyde using pyrolysis GC-MS and FTIR.

    Science.gov (United States)

    Chu, Fong Lam; Yaylayan, Varoujan A

    2008-11-26

    Benzaldehyde, a potent aroma chemical of bitter almond, can also be formed thermally from phenylalanine and may contribute to the formation of off-aroma. To identify the precursors involved in its generation during Maillard reaction, various model systems containing phenylalanine, phenylpyruvic acid, phenethylamine, or phenylacetaldehyde were studied in the presence and absence of moisture using oxidative and nonoxidative Py-GC-MS. Analysis of the data indicated that phenylacetaldehyde, the Strecker aldehyde of phenylalanine, is the most effective precursor and that both air and water significantly enhanced the rate of benzaldehyde formation from phenylacetaldehyde. Phenylpyruvic acid was the most efficient precursor under nonoxidative conditions. Phenethylamine, on the other hand, needed the presence of a carbonyl compound to generate benzaldehyde only under oxidative conditions. On the basis of the results obtained, a free radical initiated oxidative cleavage of the carbon-carbon double bond of the enolized phenylacetaldehyde was proposed as a possible major mechanism for benzaldehyde formation, and supporting evidence was provided through monitoring of the evolution of the benzaldehyde band from heated phenylacetaldehyde in the presence and absence of 1,1'-azobis(cyclohexanecarbonitrile) on the ATR crystal of an FTIR spectrophotometer. In the presence of the free radical initiator, the enol band of the phenylacetaldehyde centered at 1684 cm(-1) formed and increased over time, and after 18 min of heating time the benzaldehyde band centered at 1697 cm(-1) formed and increased at the expense of the enol band of phenylacetaldehyde, indicating a precursor product relationship.

  10. A study of catalytic activity, constituent, and structure of V-Ag catalyst for selective oxidation of toluene to benzaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Hui-Liang, Zhang; Wei, Zhong; Xiang, Duan; Xian-Cai, Fu (Nanjing Univ. (China))

    1991-06-01

    A series of V-Ag mixed oxide catalysts with various atomic ratios of V and Ag were prepared by a solution-mixing method. XRD, TEM, SMEA (surface micro-area element analysis), ESR, FT-IR, etc., were used to study the physicochemical properties of the catalysts. The experimental results showed that when silver was introduced into the vanadium pentoxide, the V{double bond}O bond was weakened, and the specific activity of the sample increased. When the atomic ratios of V/Ag were set between 3/1 and 1/1, the selectivity for benzaldehyde increased. In particular, when the V/Ag ratio equaled 2.16, the selectivity for benzaldehyde was greatest, the absorption peak of 900 cm{sup {minus}1} in FT-IR shifted to lower energy, and the relative quantity of V{sup 4 {minus}} measured with ESR appeared the highest. After reaction, XRD showed the main phases of the catalyst to exist as Ag{sub 0{center dot}80}V{sub 2}O{sub 5}, and Ag{sub 0{center dot}68}V{sub 2}O{sub 5}, with a minor Ag phase. Small amounts of VO{sub 2} and V{sub 2}O{sub 4} were also detected. On the two component oxides of vanadium-silver, the toluene oxidation appeared to proceed through two parallel reaction paths: side-chain oxidation of toluene and oxidation coupling. The sample of pure silver promoted cleavage of the carbon ring of toluene and produced deep-oxidation products in large quantity, while the sample of pure V{sub 2}O{sub 5} promoted the oxidative coupling of toluene. After the addition of silver to V{sub 2}O{sub 5}, however the oxidative coupling reaction was depressed, and the silver-vanadium oxide phases, Ag{sub 0{center dot}80}V{sub 2}O{sub 5} and Ag{sub 0{center dot}68}V{sub 2}O{sub 5} were formed. These two phases are responsible for the selective oxidation of toluene.

  11. Kinetics of the Benzaldehyde-Inhibited Oxidation of Sulfite by Chlorine Dioxide.

    Science.gov (United States)

    Pan, Changwei; Gao, Qingyu; Stanbury, David M

    2016-01-04

    There has been steady interest in the aqueous reaction of ClO2• with sulfur(IV) since the 1950s, and a wide variety of rate laws and mechanisms have been proposed. In neutral-to-alkaline media, the reaction is challenging to study because of its great rate. Here it is shown that benzaldehyde can be used as an additive to slow the reaction and make its rates more amenable to study. The rates can be quantitatively modeled by a mechanism that includes reversible binding of sulfur(IV) by benzaldehyde and a rate-limiting mixed second-order reaction of ClO2• with SO3(2-). The latter reaction occurs through parallel electron transfer from SO3(2-) to ClO2• and oxygen-atom transfer from ClO2• to SO3(2-).

  12. Selectivity modulation in the consecutive hydrogenation of benzaldehyde via functionalization of carbon nanotubes

    Institute of Scientific and Technical Information of China (English)

    Yonghua Zhou; Jing Liu; Xingyun Li; Xiulian Pan; Xinhe Bao

    2012-01-01

    Hydrogenation of benzaldehyde is a typical consecutive reaction,since the intermediate benzyl alcohol is apt to be further hydrogenated.Here we demonstrate that the selectivity of benzyl alcohol can be tuned via functionalization of carbon nanotubes (CNTs),which are used as the support of Pd.With the original CNTs,the selectivity of benzyl alcohol is 88% at a 100% conversion of benzaldehyde.With introduction of oxygen-containing groups onto CNTs,it drops to 27%.In contrast,doping CNTs with N atoms,the selectivity reaches 96% under the same reaction conditions.The kinetic study shows that hydrogenation of benzyl alcohol is significantly suppressed,which can be attributed to weakened adsorption of benzyl alcohol.This is most likely related to the modified electronic structure of Pd species via interaction with functionalized CNTs,as shown by XPS characterization.

  13. Proton transfer reactions between nitric acid and acetone, hydroxyacetone, acetaldehyde and benzaldehyde in the solid phase.

    Science.gov (United States)

    Lasne, Jérôme; Laffon, Carine; Parent, Philippe

    2012-12-01

    The heterogeneous and homogeneous reactions of acetone, hydroxyacetone, acetaldehyde and benzaldehyde with solid nitric acid (HNO(3)) films have been studied with Reflection-Absorption Infrared Spectroscopy (RAIRS) under Ultra-High Vacuum (UHV) conditions in the 90-170 K temperature range. In the bulk or at the surface of the films, nitric acid transfers its proton to the carbonyl function of the organic molecules, producing protonated acetone-H(+), hydroxyacetone-H(+), acetaldehyde-H(+) and benzaldehyde-H(+), and nitrate anions NO(3)(-), a reaction not observed when nitric acid is previously hydrated [J. Lasne, C. Laffon and Ph. Parent, Phys. Chem. Chem. Phys., 2012, 14, 697]. This provides a molecular-scale description of the carbonyl protonation reaction in an acid medium, the first step of the acid-catalyzed condensation of carbonyl compounds, fuelling the growth of secondary organic aerosols (SOA) in the atmosphere.

  14. Cu and Boron Doped Carbon Nitride for Highly Selective Oxidation of Toluene to Benzaldehyde

    Directory of Open Access Journals (Sweden)

    Hongling Han

    2015-07-01

    Full Text Available A novel Cu and boron doped graphitic carbon nitride catalyst (Cu-CNB was synthesized using cheap precursors and systematically characterized. The selective oxidation of toluene proceeded very smoothly over the catalyst at 70 °C using tert-butyl hydroperoxide (TBHP as the oxidant to exclusively afford benzaldehyde. The catalyst can be used for at least five cycles without decrease in activity and selectivity.

  15. A New Poly-substituted Benzaldehyde from the Leaves of Lysimachia fordiana Oliv.

    Directory of Open Access Journals (Sweden)

    Wen-di Deng

    2007-01-01

    Full Text Available A new poly-substituted benzaldehyde, 1, and a known compound quercetin (2 were isolated from the leaves of Lysimachia fordiana Oliv. The structure of compound 1, named fordianol, was determined as 2-heptyl-3,6-dihydroxy-4- methoxybenzaldehyde on the basis of spectroscopic methods. Fordianol did not inhibit the growth of SWO-38 (human brain neuroglioma, MCF-7 (human breast cancer or HeLa (human cervical carcinoma cell lines.

  16. VOC measurements in the Grenoble area and study of the benzaldehyde behaviour in simulation chamber

    Energy Technology Data Exchange (ETDEWEB)

    Foster, P.; Laffond, M.; Baussand, P.; Jacob, V.; Denis, I. (Grenoble-1 Univ., 38 (FR))

    1991-07-01

    The main results of three measurement campaigns carried out in the Grenoble area and concerning 22 volatile organic compounds (VOC) are presented; highly volatile organic compounds follow-up is also analyzed. The effects of two irradiation powers and two types of particles (muscovite and fly ashes) on benzaldehyde degradation in presence of OH radicals are studied. The presence of particles is shown to increase the reaction kinetic constant and modify the composition of the reaction medium.

  17. Cu and Boron Doped Carbon Nitride for Highly Selective Oxidation of Toluene to Benzaldehyde.

    Science.gov (United States)

    Han, Hongling; Ding, Guodong; Wu, Tianbin; Yang, Dexin; Jiang, Tao; Han, Buxing

    2015-07-13

    A novel Cu and boron doped graphitic carbon nitride catalyst (Cu-CNB) was synthesized using cheap precursors and systematically characterized. The selective oxidation of toluene proceeded very smoothly over the catalyst at 70 °C using tert-butyl hydroperoxide (TBHP) as the oxidant to exclusively afford benzaldehyde. The catalyst can be used for at least five cycles without decrease in activity and selectivity.

  18. Preparation and characterization of polyurethane plasticizer for flexible packaging applications: Natural oils affirmed access

    Directory of Open Access Journals (Sweden)

    Mohammed A. Mekewi

    2017-03-01

    Full Text Available Developing bio-renewable feedstock for polyurethane (PU manufacturing and polymer industry as a whole has become highly desirable for both economic and environmental reasons. In this work castor oil (CO and palm olein (PO polyols were synthesized and partially used as renewable feedstock for the manufacturing of polyurethane plasticizing resin for printing ink applications. The chemical structure of the prepared polyols and polyurethanes were characterized using IR spectra and GPC and their solubility in common solvents was tested. As well, properties such as flexibility, mechanical properties, optical properties, heat seal and freeze resistance of these prepared printing inks were determined. The results indicated that the prepared printing inks from 50% synthesized polyurethane have high thermal stability, adhesion and excellent freeze resistance. The net technical properties of the new ink formulations are relatively comparable to the printing ink prepared from standard polyurethane plasticizer.

  19. Reactions of supercritical water with benzaldehyde, benzylidenebenzylamine, benzyl alcohol and benzoic acid

    Energy Technology Data Exchange (ETDEWEB)

    Tsao, C.C.; Zhou, Y.; Liu, X.; Houser, T.J. (Western Michigan University, Kalamazoo, MI (USA). Dept. of Chemistry)

    1992-06-01

    This paper describes the results of reaction of benzaldehyde, benzyl alcohol, benzoic acid, and benzylidenebenzylamine with supercritical water (SW) since these compounds were determined or assumed to be major intermediates in the reaction of benzylamine with SW. Supplementary information was obtained from the benzyl benzoate-SW reaction. The kinetics of the benzaldehyde-SW reaction were found to be complex, second-order in benzaldehyde, and inhibited by product(s). The Arrhenius parameters for the second-order rate constant are an activation energy of 179 kJ mol[sup -1] and preexponential factor of 1.6 x 10 (10) M[sup -1]s[sup -1]. In addition, the influences of ammonia and dihydroanthracene on some of the product distributions and extents of reaction were determined. Of particular interest is the reaction pathway leading to the formation of benzene and related products which requires an oxidation/hydrolysis sequence, terminated by decarboxylation to form hydrocarbons. The mechanistic significance of the benzene/tpluene product-yield ratios is discussed.

  20. Oscillations and complex mechanisms: O/sub 2/ oxidation of benzaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Roelofs, M.G.; Wasserman, E.; Jensen, J.H.

    1987-07-08

    The oxidation of benzaldehyde catalyzed by cobalt and bromine is an oscillating reaction in which the concentrations of Co(III) and of dissolved oxygen vary periodically with time. A mechanistic model is proposed in which the reaction alternates between two stages. In stage I the dissolved oxygen concentration is appreciable and benzoyl radicals combine with oxygen, ultimately oxidizing Co(II) to Co(III). In stage II dissolved oxygen is depleted, and benzoyl radicals are oxidized by Co(III). The model gives satisfactory agreement with a number of qualitative and quantitative features. These include the composition of the steady states and the amplitude and period of oscillation for different concentrations of cobalt, bromide, and benzaldehyde. Specific measurements were also made of the kinetics of the reduction of cobalt(III) by mixtures of benzaldehyde and sodium bromide, the stability of a cobalt-bromide complex, and the consumption of /sup 18/O/sub 2/. This last study demonstrates the presence of two major pathways to benzoic acid which differ in the source of oxygen.

  1. CaCO{sub 3}/Ca-P biphasic materials prepared by microwave processing of natural aragonite and calcite

    Energy Technology Data Exchange (ETDEWEB)

    Pena, J.; LeGeros, R.Z.; Rohanizadeh, R.; LeGeros, J.P. [New York Univ., NY (United States). Coll. of Dentistry

    2001-07-01

    The purpose of this study was to prepare CaCO{sub 3}/Ca-P biphasic or composite materials using microwave technology. Particles of coral (natural aragonite) and a porous limestone (natural calcite) were suspended in phosphate solutions of different pH and concentrations and heated for different periods (up to 5 hrs) using a domestic microwave. Parallel experiments were carried out using hydrolysis method. Higher extents of transformation were observed with microwave processed materials. Depending on the reaction pH and reaction period, partial transformation of aragonite (coral) or calcite (limestone) to acidic calcium (monetite) or basic (carbonatehydroxyapatite, CHA) calcium phosphates was achieved (orig.)

  2. natural

    Directory of Open Access Journals (Sweden)

    Elías Gómez Macías

    2006-01-01

    Full Text Available Partiendo de óxido de magnesio comercial se preparó una suspensión acuosa, la cual se secó y calcinó para conferirle estabilidad térmica. El material, tanto fresco como usado, se caracterizó mediante DRX, área superficial BET y SEM-EPMA. El catalizador mostró una matriz de MgO tipo periclasa con CaO en la superficie. Las pruebas de actividad catalítica se efectuaron en lecho fijo empacado con partículas obtenidas mediante prensado, trituración y clasificación del material. El flujo de reactivos consistió en mezclas gas natural-aire por debajo del límite inferior de inflamabilidad. Para diferentes flujos y temperaturas de entrada de la mezcla reactiva, se midieron las concentraciones de CH4, CO2 y CO en los gases de combustión con un analizador de gases tipo infrarrojo no dispersivo (NDIR. Para alcanzar conversión total de metano se requirió aumentar la temperatura de entrada al lecho a medida que se incrementó el flujo de gases reaccionantes. Los resultados obtenidos permiten desarrollar un sistema de combustión catalítica de bajo costo con un material térmicamente estable, que promueva la alta eficiencia en la combustión de gas natural y elimine los problemas de estabilidad, seguridad y de impacto ambiental negativo inherentes a los procesos de combustión térmica convencional.

  3. Biotransformation of Benzaldehyde to L-Phenylacetylcarbinol (L-PAC by Free Cells of Torulaspora delbrueckii in presence of Beta-Cyclodextrin

    Directory of Open Access Journals (Sweden)

    Vilas. B. Shukla

    2002-09-01

    Full Text Available Studies were carried out to explore the possibility of decreasing the toxic and inhibitory effects of the substrate benzaldehyde during its biotransformation to L-PAC by free cells of Torulaspora delbrueckii using beta -cyclodextrin (beta -CD. Use of various levels of benzaldehyde and acetaldehyde in presence of 2% of beta -CD showed that, in presence of beta -CD, the organism could tolerate higher levels of benzaldehyde and acetaldehyde. Semi-continuous feeding of benzaldehyde and acetaldehyde was found to increase the yield of L-PAC in comparison with one time feeding.

  4. Growth and characterization of novel organic 3-Hydroxy Benzaldehyde-N-methyl 4 Stilbazolium Tosylate crystals for NLO applications

    Science.gov (United States)

    Jagannathan, K.; Umarani, P.; Ratchagar, V.; Ramesh, V.; Kalainathan, S.

    2016-01-01

    The 3-Hydroxy Benzaldehyde-N-methyl 4-Stilbazolium Tosylate (3- HBST) is a new organic NLO crystal and it is a new derivative in stilbazolium tosylate family. In this work we have synthesized 3-HBST and the single crystal was grown by conventional slow cooling method. The structure and lattice parameters of the grown crystal were determined by the single crystal X-ray diffraction (XRD) technique and it is exhibiting good crystalline nature which is observed from the powder XRD. In order to check the crystalline quality the rocking curve was recorded using multi crystal X-ray diffractometer. The functional groups were identified from both FTIR and NMR spectral analyses. The π-π* and n-π* optical transition energy levels were estimated from the absorption peaks. The NLO property was confirmed by measuring relative SHG efficiency by Kurtz powder test; it shows 24 times higher SHG efficiency than that of urea. In order to test the mechanical stability the Vickers and Knoop micro hardness measurement were carried out and found that the micro hardness number decreases with increasing load. The melting point was determined from Differential Scanning Colorimetry (DSC).

  5. Enhanced benzaldehyde tolerance in Zymomonas mobilis biofilms and the potential of biofilm applications in fine-chemical production.

    Science.gov (United States)

    Li, Xuan Zhong; Webb, Jeremy S; Kjelleberg, Staffan; Rosche, Bettina

    2006-02-01

    Biotransformation plays an increasingly important role in the industrial production of fine chemicals due to its high product specificity and low energy requirement. One challenge in biotransformation is the toxicity of substrates and/or products to biocatalytic microorganisms and enzymes. Biofilms are known for their enhanced tolerance of hostile environments compared to planktonic free-living cells. Zymomonas mobilis was used in this study as a model organism to examine the potential of surface-associated biofilms for biotransformation of chemicals into value-added products. Z. mobilis formed a biofilm with a complex three-dimensional architecture comprised of microcolonies with an average thickness of 20 microm, interspersed with water channels. Microscopic analysis and metabolic activity studies revealed that Z. mobilis biofilm cells were more tolerant to the toxic substrate benzaldehyde than planktonic cells were. When exposed to 50 mM benzaldehyde for 1 h, biofilm cells exhibited an average of 45% residual metabolic activity, while planktonic cells were completely inactivated. Three hours of exposure to 30 mM benzaldehyde resulted in sixfold-higher residual metabolic activity in biofilm cells than in planktonic cells. Cells inactivated by benzaldehyde were evenly distributed throughout the biofilm, indicating that the resistance mechanism was different from mass transfer limitation. We also found that enhanced tolerance to benzaldehyde was not due to the conversion of benzaldehyde into less toxic compounds. In the presence of glucose, Z. mobilis biofilms in continuous cultures transformed 10 mM benzaldehyde into benzyl alcohol at a steady rate of 8.11 g (g dry weight)(-1) day(-1) with a 90% molar yield over a 45-h production period.

  6. [The protective action of a natural preparation of anthocyan (pelargonidin-3,5-diglucoside)].

    Science.gov (United States)

    Akhmadieva, A Kh; Zaichkina, S I; Ruzieva, R Kh; Ganassi, E E

    1993-01-01

    The effect of an anthocyan preparation isolated from flower petals of Pelargonium roseum and Rosa canina was studied in the Chinese hamster fibroblasts and Vicia faba seedlings in respect of cytogenetic damage and mouse survival. The pronounced radioprotective effect and the absence of the toxic effect were observed.

  7. Facial Toner Preparation Using Distilled Fragrant Compounds of Natural Herbal Plants

    Science.gov (United States)

    Liao, Wayne C.; Lien, Ching-Yi

    2011-01-01

    This experiment is designed to teach entry-level, nonchemistry-major students some basic organic chemistry through the procedure for making cosmetics. The experiment combines facial toner preparation with distillation techniques to create a stimulating learning environment. During the experiment, students perform a distillation to collect some…

  8. Influence of the Surfactant Nature on the Occurrence of Self-Assembly between Rubber Particles and Thermally Reduced Graphite Oxide during the Preparation of Natural Rubber Nanocomposites

    Directory of Open Access Journals (Sweden)

    Héctor Aguilar-Bolados

    2015-01-01

    Full Text Available The natural rubber (NR latex consists of polymer particles charged negatively due to the adsorbed phospholipids and proteins molecules. The addition of stable aqueous suspension of thermally reduced graphite oxide (TRGO stabilized by ionic surfactants to NR latex can favor the occurrence of interaction between the stabilized TRGO and NR particles. Herein, the use of two surfactants of different nature, namely, sodium dodecyl sulfate (SDS and dodecyltrimethylammonium bromide (DTAB, for the preparation of (TRGO/NR nanocomposites, is reported. Zeta potential and particle size measurements indicated that the use of DTAB as cationic surfactant results in the flocculation of NR particles and promoted the formation of ion-pair interactions between TRGO and the proteins and/or phospholipids present on the NR surface. This indicates that the use of DTAB can promote a self-assembly phenomenon between TRGO with adsorbed DTAB molecules and NR particles. The occurrence of self-assembly phenomenon allows obtaining homogenous dispersion of TRGO particles in the polymer matrix. The TRGO/NR nanocomposites prepared by the use of DTAB exhibited superior mechanical properties and excellent electrical conductivities reaching values of stress at 500% strain of 3.02 MPa and 10−4 S/cm, respectively.

  9. A Nutrition and Conditioning Intervention for Natural Bodybuilding Contest Preparation: Case Study.

    OpenAIRE

    Robinson, S.L.; Lambeth-Mansell, Annie; Gillibrand, G.; Smith-Ryan, A.; Bannock, L

    2015-01-01

    Bodybuilding competitions are becoming increasingly popular. Competitors are judged on their aesthetic\\ud appearance and usually exhibit a high level of muscularity and symmetry and low levels of body fat. Commonly used techniques to improve physique during the preparation phase before competitions include dehydration, periods of prolonged fasting, severe caloric restriction, excessive cardiovascular exercise and inappropriate use of diuretics and anabolic steroids. In contrast, this case stu...

  10. Radioactivity of natural medicinal preparations contained extracts from peat mud available in retail trade used externally.

    Science.gov (United States)

    Karpińska, Maria; Kapała, Jacek; Raciborska, Agnieszka; Kulesza, Grzegorz; Milewska, Anna; Mnich, Stanisław

    2017-08-01

    In this work were identified and measured the activity of radioactive isotopes present in medicinal preparations from peat mud and estimated the doses obtained from them during therapy. Radioactivity of 22 preparations from peat mud and 20 water samples from water of the North-East region of Poland was studied. The median of the total activity was 24.8 Bq kg(-1). Total maximal isotope activity was observed in the Iwonicka Cube 146 Bq kg(-1) while considerable amounts of isotopes were found in the Kolobrzeska Peat Mud Paste 112 Bq kg(-1). The doses obtained during therapy were within the range of 11 nSv-13 μSv depending on extracts of medicinal preparations from peat mud. The probability that such a small dose would stimulate biological effects is low. However, some clinicians believe that one of the possible therapeutic mechanisms in the treatment of rheumatoid disorders is the induction of immune response by ionising radiation.

  11. Mass spectra of benzaldehyde using time resolved ion trapping mass spectrometer. Jikan bunkai ion trapping shitsuryo bunsekikei ni yoru benzaldehyde no mass spector

    Energy Technology Data Exchange (ETDEWEB)

    Ishigane, M.; Isa, K. (Fukui Univ., Fukui (Japan). Faculty of Education); Nishioka, K. (Fukui Univ., Fukui (Japan). Faculty of Engineering)

    1991-12-28

    An ion trapping mass spectrometer for time resolved analysis has been set up. The time resolved analysis function of this system is excellent and the ion detecting sensitivity is also high. Benzaldehyde is used as the specimen for the measurement of the A group of the mass spectra (m/z 105 106 and 107) by this system and similar mass spectra are obtained at delay time zero to those reported by now. Big changes are observed in the spectra when the delay times are varied. It is found that mass spectra which are different from those reported already are obtained when the mass spectrometer is pulse operated. In other words it can be said that the time dependence of the data on ion decomposition ( fragmentation) and ion/molecule reactions can be obtained in the state where solvent has no influence if this new system is adopted. 6 refs. 12 figs.

  12. Probing the Active Center of Benzaldehyde Lyase with Substitutions and the Pseudosubstrate Analogue Benzoylphosphonic Acid Methyl Ester

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, Gabriel S.; Nemeria, Natalia; Chakraborty, Sumit; McLeish, Michael J.; Yep, Alejandra; Kenyon, George L.; Petsko, Gregory A.; Jordan, Frank; Ringe, Dagmar (Rutgers); (Michigan); (Brandeis)

    2008-07-28

    Benzaldehyde lyase (BAL) catalyzes the reversible cleavage of (R)-benzoin to benzaldehyde utilizing thiamin diphosphate and Mg{sup 2+} as cofactors. The enzyme is important for the chemoenzymatic synthesis of a wide range of compounds via its carboligation reaction mechanism. In addition to its principal functions, BAL can slowly decarboxylate aromatic amino acids such as benzoylformic acid. It is also intriguing mechanistically due to the paucity of acid-base residues at the active center that can participate in proton transfer steps thought to be necessary for these types of reactions. Here methyl benzoylphosphonate, an excellent electrostatic analogue of benzoylformic acid, is used to probe the mechanism of benzaldehyde lyase. The structure of benzaldehyde lyase in its covalent complex with methyl benzoylphosphonate was determined to 2.49 {angstrom} (Protein Data Bank entry 3D7K) and represents the first structure of this enzyme with a compound bound in the active site. No large structural reorganization was detected compared to the complex of the enzyme with thiamin diphosphate. The configuration of the predecarboxylation thiamin-bound intermediate was clarified by the structure. Both spectroscopic and X-ray structural studies are consistent with inhibition resulting from the binding of MBP to the thiamin diphosphate in the active centers. We also delineated the role of His29 (the sole potential acid-base catalyst in the active site other than the highly conserved Glu50) and Trp163 in cofactor activation and catalysis by benzaldehyde lyase.

  13. Probing the active center of benzaldehyde lyase with substitutions and the pseudosubstrate analogue benzoylphosphonic acid methyl ester.

    Science.gov (United States)

    Brandt, Gabriel S; Nemeria, Natalia; Chakraborty, Sumit; McLeish, Michael J; Yep, Alejandra; Kenyon, George L; Petsko, Gregory A; Jordan, Frank; Ringe, Dagmar

    2008-07-22

    Benzaldehyde lyase (BAL) catalyzes the reversible cleavage of ( R)-benzoin to benzaldehyde utilizing thiamin diphosphate and Mg (2+) as cofactors. The enzyme is important for the chemoenzymatic synthesis of a wide range of compounds via its carboligation reaction mechanism. In addition to its principal functions, BAL can slowly decarboxylate aromatic amino acids such as benzoylformic acid. It is also intriguing mechanistically due to the paucity of acid-base residues at the active center that can participate in proton transfer steps thought to be necessary for these types of reactions. Here methyl benzoylphosphonate, an excellent electrostatic analogue of benzoylformic acid, is used to probe the mechanism of benzaldehyde lyase. The structure of benzaldehyde lyase in its covalent complex with methyl benzoylphosphonate was determined to 2.49 A (Protein Data Bank entry 3D7K ) and represents the first structure of this enzyme with a compound bound in the active site. No large structural reorganization was detected compared to the complex of the enzyme with thiamin diphosphate. The configuration of the predecarboxylation thiamin-bound intermediate was clarified by the structure. Both spectroscopic and X-ray structural studies are consistent with inhibition resulting from the binding of MBP to the thiamin diphosphate in the active centers. We also delineated the role of His29 (the sole potential acid-base catalyst in the active site other than the highly conserved Glu50) and Trp163 in cofactor activation and catalysis by benzaldehyde lyase.

  14. Amino acid-catalysed retroaldol condensation: the production of natural benzaldehyde and other flavour compounds

    NARCIS (Netherlands)

    Wolken, W.A.M.; Tramper, J.; Werf, van der M.J.

    2004-01-01

    The amino acid-catalysed retroaldol condensation previously described for citral has been extended to other alpha,beta-unsaturated aldehydes. In the presence of glycine and an elevated pH, six other alpha,beta-unsaturated aldehydes also underwent retroaldol condensation. Crotonaldehyde, as well as i

  15. Amino acid-catalysed retroaldol condensation : the production of natural benzaldehyde and other flavour compounds

    NARCIS (Netherlands)

    Wolken, WAM; Tramper, J; van der Werf, MJ

    2004-01-01

    The amino acid-catalysed retroaldol condensation previously described for citral has been extended to other alpha,beta-unsaturated aldehydes. In the presence of glycine and an elevated pH, six other alpha,beta-unsaturated aldehydes also underwent retroaldol condensation. Crotonaldehyde, as well as i

  16. Amino acid-catalysed retroaldol condensation: The production of natural benzaldehyde and other flavour compounds

    NARCIS (Netherlands)

    Wolken, W.A.M.; Tramper, J.; Werf, M.J. van der

    2004-01-01

    The amino acid-catalysed retroaldol condensation previously described for citral has been extended to other α,β -unsaturated aldehydes. In the presence of glycine and an elevated pH, six other α,β-unsaturated aldehydes also underwent retroaldol condensation. Crotonaldehyde, as well as its proposed i

  17. Amino acid-catalysed retroaldol condensation: the production of natural benzaldehyde and other flavour compounds

    NARCIS (Netherlands)

    Wolken, W.A.M.; Tramper, J.; Werf, van der M.J.

    2004-01-01

    The amino acid-catalysed retroaldol condensation previously described for citral has been extended to other alpha,beta-unsaturated aldehydes. In the presence of glycine and an elevated pH, six other alpha,beta-unsaturated aldehydes also underwent retroaldol condensation. Crotonaldehyde, as well as i

  18. Amino acid-catalysed retroaldol condensation : the production of natural benzaldehyde and other flavour compounds

    NARCIS (Netherlands)

    Wolken, WAM; Tramper, J; van der Werf, MJ

    2004-01-01

    The amino acid-catalysed retroaldol condensation previously described for citral has been extended to other alpha,beta-unsaturated aldehydes. In the presence of glycine and an elevated pH, six other alpha,beta-unsaturated aldehydes also underwent retroaldol condensation. Crotonaldehyde, as well as i

  19. Amino acid-catalysed retroaldol condensation: The production of natural benzaldehyde and other flavour compounds

    NARCIS (Netherlands)

    Wolken, W.A.M.; Tramper, J.; Werf, M.J. van der

    2004-01-01

    The amino acid-catalysed retroaldol condensation previously described for citral has been extended to other α,β -unsaturated aldehydes. In the presence of glycine and an elevated pH, six other α,β-unsaturated aldehydes also underwent retroaldol condensation. Crotonaldehyde, as well as its proposed i

  20. Simultaneous preparation of naturally abundant and rare catechins by tannase-mediated biotransformation combining high speed counter current chromatography.

    Science.gov (United States)

    Xia, Guobin; Hong, Shan; Liu, Songbai

    2014-05-15

    Simultaneous preparation of naturally rare catechins, EGC and EC, has been realized by tannase-mediated biotransformation combining high speed counter current chromatography. In addition, simultaneous preparation of the four catechins, EGCG, ECG, EGC, and EC in green tea extract has also been achieved by HSCCC under the normal phase and the reversed phase modes. The identity of the catechins was determined by HPLC-DAD-ESI-MS and quantification of the catechins was performed by HPLC-DAD. In a typical HSCCC separation, 27.2 mg 98.8% EGCG, 14.1 mg 94.7% EGC, and 9.3 mg 97.5% EC were obtained. This new method is efficient, time-saving and valuable for biological studies.

  1. Aging Time Effect on Porous Characteristics of Natural Mud-based Silica Prepared by Hydrothermal-Coprecipitation Route

    Science.gov (United States)

    Ubaid, A.; Hidayat, N.; Munasir

    2017-05-01

    In this present study, we report the influence of aging time on porous characteristics and chemical bonding within structurally related silicates of silica. The silica was well prepared by using a combination of hydrothermal and coprecipitation methods. Local natural mud from Sidoarjo, Indonesia was preferred as a starting material, rather than the expensive commercial ones. The aging time was set at 20, 24, 28, and 32 hours. The X-ray fluorescence (XRF) test revealed that the produced porous silica has a purity of 98.9%. The Fourier Transform of Infra-Red (FTIR) analysis showed that ≡Si-OH and ≡Si-O -Si≡ functional groups were found in the samples. The pores of the silica, after Brunauer-Emmett-Teller (BET) measurement, found to be macropore and mesopore. The prepared silica with different porous characteristics were strongly influenced by the chemical activities during the synthesis, known as syneresis and Ostwald processes.

  2. A 5E Nature of Science Introduction: Preparing Students to Learn about Evolution

    Science.gov (United States)

    Bilica, Kimberly

    2012-01-01

    Teachers often struggle with controversy when teaching biological evolution in American schools. Research indicates that curriculum with a nature of science (NOS) focus quells controversy (McComas 2004; Scharmann 2005; Staver 2003). This article presents a 5E NOS series that is a first step in a NOS curriculum that situates student understanding…

  3. A 5E Nature of Science Introduction: Preparing Students to Learn about Evolution

    Science.gov (United States)

    Bilica, Kimberly

    2012-01-01

    Teachers often struggle with controversy when teaching biological evolution in American schools. Research indicates that curriculum with a nature of science (NOS) focus quells controversy (McComas 2004; Scharmann 2005; Staver 2003). This article presents a 5E NOS series that is a first step in a NOS curriculum that situates student understanding…

  4. Preservice Professional Preparation and Teachers' Self-Efficacy Appraisals of Natural Environment and Inclusion Practices

    Science.gov (United States)

    Dunst, Carl J.; Bruder, Mary Beth

    2014-01-01

    This paper includes results from a study that examined the relationships between teacher discipline, type of teaching degree, and teacher feelings of preparedness and the self-efficacy beliefs (competence and confidence) of early intervention and preschool teachers with regard to either natural environment or inclusion practices. The participants…

  5. Food consumption and growth rates of juvenile black carp fed natural and prepared feeds

    Science.gov (United States)

    Hodgins, Nathaniel C.; Schramm, Harold L.; Gerard, Patrick D.

    2014-01-01

    The introduced mollusciphagic black carp Mylopharyngodon piceus poses a significant threat to native mollusks in temperate waters throughout the northern hemisphere, but consumption rates necessary to estimate the magnitude of impact on mollusks have not been established. We measured food consumption and growth rates for small (77–245 g) and large (466–1,071 g) triploid black carp held individually under laboratory conditions at 20, 25, and 30°C. Daily consumption rates (g food · g wet weight fish−1·d−1·100) of black carp that received prepared feed increased with temperature (small black carp 1.39–1.71; large black carp 1.28–2.10), but temperature-related increases in specific growth rate (100[ln(final weight) - ln(initial weight)]/number of days) only occurred for the large black carp (small black carp −0.02 to 0.19; large black carp 0.16–0.65). Neither daily consumption rates (5.90–6.28) nor specific growth rates (0.05–0.24) differed among temperatures for small black carp fed live snails. The results of these laboratory feeding trials indicate food consumption rates can vary from 289.9 to 349.5 J·g−1·d−1 for 150 g black carp receiving prepared feed, from 268.8 to 441.0 J·g−1·d−1for 800 g black carp receiving prepared feed, and from 84.8 to 90.2 J·g−1·d−1 for 150 g black carp that feed on snails. Applying estimated daily consumption rates to estimated biomass of native mollusks indicates that a relatively low biomass of bla

  6. Assessment of natural and synthetic wollastonite as source for bioceramics preparation.

    Science.gov (United States)

    Carrodeguas, R G; De Aza, A H; De Aza, P N; Baudín, C; Jiménez, J; López-Bravo, A; Pena, P; De Aza, S

    2007-11-01

    Pseudowollastonite ceramics (beta-CaSiO3) from synthetic and natural sources were assessed with regard to their properties relevant to biomedical applications. Synthetic and natural CaSiO3 powders, with average particle size of 1.6 and 13.2 microm, respectively, were first employed. Powders were pressed and sintered at 1400 degrees C for 2 h. Pseudowollastonite was the only crystalline phase in sintered materials. Glassy phase, eight times more abundant in sintered natural wollastonite (SNW) than in the synthetic one (SSW), was observed in grain boundaries and in triple points. Larger grains and bigger and more abundant pores were present in SNW, resulting in lower diametral tensile strength (26 MPa), than in SSW (42 MPa). However, by milling the natural wollastonite starting powder to a particle size of 2.0 microm and sintering (SNW-M), the microstructure became finer and less porous, and diametral tensile strength increased (48 MPa). Weibull modulus of SNW and SNW-M samples was twice that of the SSW. All the samples released Si and Ca ions, and removed phosphate ions from simulated body fluid in similar amounts and were completely coated by apatite-like spherules after soaking in simulated body fluid for 3 wk. The aqueous extracts from all samples studied were not cytotoxic in a culture of human fibroblastic cells. No differences in fibroblast-like human cells adhesion and proliferation were observed between samples. According to the obtained results, properly processed pseudowollastonite bioceramics, obtained from the natural source, exhibit the same in vitro behavior and better performance in terms of strength and reliability than do the more expensive synthetic materials. Copyright (c) 2007 Wiley Periodicals, Inc.

  7. The influence of reduction methods and conditions on the activity of alumina-supported platinum catalysts for the liquid phase hydrogenation of benzaldehyde in ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Arai, M.; Obata, A.; Nishiyama, Y. [Tohoku Univ., Sendai (Japan)

    1997-02-01

    The activities of supported metal catalysts depend on various preparation variables, including the method of reduction. A variety of reduction procedures can be applied to the preparation of supported metal catalysts. Previously, the authors used a solid-liquid reduction by sodium tetrahydroborate solution for preparing supported platinum catalysts. In this reduction, platinum precursors adsorbed on supports were brought into contact with the reducing solution. The alumina-supported platinum catalysts prepared in this way were found to display interesting activities in the liquid-phase hydrogenation of {alpha},{beta}-unsaturated aldehydes; they were highly selective to the formation of unsaturated alcohols. The selective hydrogenation of C=O bonds of {alpha},{beta}-unsaturated aldehydes is difficult to achieve with platinum catalysts without using some additives like tin and iron. The maximum temperature that the supported platinum catalysts went through was 110{degrees}C, required for the removal of water. This thermal history is a possible reason for the catalytic activity observed. Following those observations, in the present work, the authors have further examined the influence of reduction procedures by using hydrazine as well as sodium tetrahydroborate and different temperatures common during gas-phase reduction with hydrogen. The catalytic activity has been tested by the liquid-phase hydrogenation of benzaldehyde (BAL) in ethanol under mild conditions. 12 refs., 3 figs.

  8. The Preparation of New Phosphorus-Centered Functional Groups for Modified Oligonucleotides and Other Natural Phosphates

    Directory of Open Access Journals (Sweden)

    S. Piettre

    2005-09-01

    Full Text Available Efforts to develop synthetic methodologies allowing the preparation of α,α– difluorophosphonothioates, α,α–difluorophosphonodithioates, α,α–difluorophosphono- trithioates, and α,α–difluorophosphinates are reviewed in the light of applications in the field of modified oligonucleotides and cyclitol phosphates. Two successful approaches have been developed, based either on the addition of phosphorus-centered radicals onto gem–difluoroalkenes or on a process involving the addition of lithiodifluorophosphono- thioates 91 onto a ketone and the subsequent deoxygenation reaction of the adduct. The radical route successfully developed a practical route to α,α–difluoro–H–phosphinates which proved to be useful intermediates to a variety of phosphate isosters. The ionic route led to the first preparation of phosphonodifluoromethyl analogues of nucleoside– 3’–phosphates.

  9. PREPARATION MICRO-FILTRATION CERAMIC MEMBRANE FROM NATURAL ZEOLITE FOR PROCION RED MX8B AND METHYLENE BLUE FILTRATION

    Directory of Open Access Journals (Sweden)

    Dyah Choiriyah

    2015-12-01

    Full Text Available The study of ceramic membrane fabrication from natural zeolite and its utilization for filtration of procion red MX8B and methylene blue has been investigated. The purposes of this study are to determine the effect of pressure on membrane permeability and selectivity and utilize natural zeolite as ceramic membranes procion red MX8B and methylene blue filtration. The membrane was prepared by metide press pellets and then calcined at 850 oC. The membranes were characterized by mechanical test, flux and rejection of dye. The compression test of the membrane found the values of 1369.178 psi in dry conditions to 1388.933 psi in wet conditions. The flux test found that the higher the pressure applied, the flux was increase. However, the high pressure also decreased the selectivity. Rejection test found that the rejection of methylene blue filtration up to 70 %. Meanwhile, procion red MX8B filtration has rejectivity less than 20 %.

  10. Reactions of Chlorine Gas on Benzaldehyde-di-n-alkyl Acetals

    Directory of Open Access Journals (Sweden)

    A. Edwin Vasu

    2008-01-01

    Full Text Available Reactions of chlorine gas on six aromatic acetals, the benzaldehyde di-n-alkyl acetals, C6H4-CH(OR2 where R=ethyl (1a, n-propyl (2a, n-butyl (3a, isobutyl (4a, n-amyl (5a and isoamyl (6a were studied. The products were analyzed by IR and 1H NMR spectroscopic techniques and were found to be ring chlorinated alkyl benzoates. A plausible mechanism has been proposed based on the experimental observations and the effect of the alkyl groups on the product yield.

  11. Kinetics and mechanism of the thermal decomposition of unsaturated aldehydes: benzaldehyde, 2-butenal, and 2-furaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Grela, M.A.; Colussi, A.J.

    1986-01-30

    The thermal unimolecular decomposition of benzaldehyde (BA), crotonaldehyde (CA), and furfural (FA) have been investigated in a flow reactor at very low pressures by modulated beam mass spectrometry above 1040 K. Each reaction proceeds by a different mechanism. Whereas BA decomposes by C(O)-H bond fission CA readily undergoes decarbonylation to propene via a three-center transition-state reaction. FA decomposition into vinylketene and CO involves ring opening followed by H-atom transfer in the resulting biradical. Overall high-pressure Arrhenius parameters for the three reactions are derived from kinetic data. 26 references, 4 figures, 1 table.

  12. The effect of metal-support interactions on the hydrogenation of benzaldehyde and benzyl alcohol

    Energy Technology Data Exchange (ETDEWEB)

    Vannice, M.A.; Poondi, D. [Pennsylvania State Univ., University Park, PA (United States)

    1997-07-01

    The hydrogenation of benzaldehyde hydrogenation on Pt/TiO{sub 2} after a high-temperature reduction (HTR) step, compared to either Pt/TiO{sub 2} after a low-temperature reduction (LTR) step, Pt/SiO{sub 2} or Pt/Al{sub 2}O{sub 3} is discussed. Pt/TiO{sub 2} (HTR) retained a selectivity to benzyl alcohol of 100% up to conversions of 80%, whereas significant amounts of toluene and benzene began to be formed at conversions above 20% with the other Pt catalysts, including Pt powder. 39 refs., 6 figs., 7 tabs.

  13. Synthesis of Aminophosphine Ligands with Binaphthyl Backbones for Silver(I)-catalyzed Enantioselective Allylation of Benzaldehyde

    Institute of Scientific and Technical Information of China (English)

    WANG,Yi(王以); JI,Bao-Ming(吉保明); DING,Kui-Ling(丁奎岭)

    2002-01-01

    A series of aminophosphine ligands was synthesized from 2amino-2′-hydroxy-1,1′-binaphthyl (NOBIN). Their asymmetric induction efficiency was examined for silver(I)catalyzed enantioselective allylation reaction of benzaldehyde with allyltributyltin.Under the optimized reaction conditions,quantitative yield as well as moderate ee value (54.5% ee)of product was achieved by the catalysis with silver(I)/3 complex. The effects of the binaphthyl backbone and the substituted situated at chelating N, Patoms on enantioselectivity of the reaction were also discussed.

  14. A Novel Acetate Selective UV-Vis Chemosensor Containing a Tripodal Benzaldehydic-phenylhydrazone

    Institute of Scientific and Technical Information of China (English)

    QIAO Yan-Hong; LIN Hai; SHAO Jie; LIN Hua-Kuan

    2008-01-01

    A new colorimetric chemosensor 1 based on a tripodal benzaldehydic-phenylhydrazone selectively sensing acetate ion has been synthesized. The highly selective binding ability of receptor I to acetate ion over other studied anions was demonstrated by UV-Vis absorption spectroscopy in DMSO. Compared with other anions studied, its sorption spectrum change has occurred when receptor 1 was treated with other different guest anions (F-, Cl-, Br-,I-, H2PO4- and OH-). The Kass of receptor 1 binding with acetate ion is 1.69×104.

  15. Engineering NiO sensitive materials and its ultra-selective detection of benzaldehyde.

    Science.gov (United States)

    Yang, Fuchao; Guo, Zhiguang

    2016-04-01

    Ongoing interest in oxide semiconductor as components of gas sensing devices is motivated by environmental monitoring and intelligent control. NiO with different precursor solution were synthesized by aqueous chemical deposition and pyrolysis process. Here the method is quite facile, green and free of surfactant. Their morphology, crystal structure and chemical composition have been systemically characterized by various techniques. Interestingly, the microstructures of NiO can be engineered by different nickel salt (nitrate or chloride). These NiO based gas sensors showed substantially enhanced responses to benzaldehyde target analyte and exhibited fast response-recover feature. The observed gas sensing behavior is explained in terms of oxygen ionosorption mechanism.

  16. Crystal structure of 4-(4-meth-oxy-phen-oxy)benzaldehyde.

    Science.gov (United States)

    Schäfer, Andreas; Iovkova-Berends, Ljuba; Gilke, Stefan; Kossmann, Paul; Preut, Hans; Hiersemann, Martin

    2015-12-01

    The title compound, C14H12O3, was synthesized via the nucleophilic addition of 4-meth-oxy-phenol to 4-fluoro-benzaldehyde. The dihedral angle between the least-squares planes of the benzene rings is 71.52 (3)° and the C-O-C angle at the central O atom is 118.82 (8)°. In the crystal, weak C-H⋯O hydrogen bonds link the molecules to generate supra-molecular layers in the bc plane. The layers are linked by weak C-H⋯π inter-actions.

  17. Aqueous high-temperature chemistry of carbo- and heterocycles. 2. Monosubstituted benzenes: Benzyl alcohol, benzaldehyde, and benzoic acid

    Energy Technology Data Exchange (ETDEWEB)

    Katritzky, A.R.; Balasubramanian, M. (Univ. of Florida, Gainesville (USA)); Siskin, M. (Exxon Research and Engineering Company, Annandale, NJ (USA))

    Benzyl alcohol is not very reactive under aquathermolysis conditions, except in the presence of acids. Almost all the products are formed by ionic pathways. It undergoes reversible dehydration to dibenzyl ether, disproportionation to benzaldehyde and toluene, and self-benzylation to 2- and 4-benzylbenzyl alcohols. These benzylbenzyl alcohols can react further, but major amounts of polyalkylated products are formed by the mono- and dibenzylation of toluene to give a range of dibenzyltoluenes and (benzylbenzyl)toluenes. Small amounts of diphenylmethane and bibenzyl and their benzylated products are also formed. The behavior of benzyl alcohol in the presence of phenol, pyridine, benzaldehyde, and benzene is also studied and rationalized. Benzaldehyde is much less reactive, except in the presence of formaldehyde, and especially in the presence of formic acid, when considerable formation of benzyl alcohol occurs and siphoning into this reaction matrix is observed. Benzoic acid is still less reactive.

  18. Characterisation of natural fibre reinforced PLA foams prepared by supercritical CO2 assisted extrusion

    Directory of Open Access Journals (Sweden)

    K. Bocz

    2016-09-01

    Full Text Available Natural fibre reinforced polylactic acid (PLA foams, as potential green replacements for petroleum-based polymer foams, were investigated. Highly porous (ε > 95% microcellular PLA foams were manufactured by supercritical CO2 assisted extrusion process. To overcome the inherently low melt strength of PLA, epoxy-functionalized chain extender was applied, while talc was added to improve its crystallization kinetics. The combined application of chain extender and talc effectively promoted the formation of uniform cell structures. The effect of cellulose and basalt fibre reinforcement on the foamability, morphology, structure and mechanical properties of the PLA foams were investigated as well. The addition of 5 wt% natural fibres promoted the cell nucleation, but caused non-uniform distribution of cell size due to the microholes induced by local fibre-matrix debonding. The compression strength of the manufactured basalt fibre reinforced PLA foams reached 40 kPa.

  19. [The role of ancient astrology in preparation for a secular natural science and medicine].

    Science.gov (United States)

    Geller, Markham J

    2011-01-01

    The Persian period in the Near East (from c. 500 BCE) represented the first example of globalisation, during which advanced cultural centres from Egypt to Afghanistan were united under a single rule and common language. Paul Unschuld has drawn attention to a scientific revolution in the late first millennium BC, extending from Greece to China, from Thales to Confucius, which saw natural law replace the divine law in scientific thinking. This paper argues for new advances in astronomy as the specific motor which motivated changes in scientific thinking and influenced other branches of science, including medicine, just as the new science of astrology, which replaced divination, fundamentally changed the nature of medical prognoses. The secularisation of science was not universally accepted among ancient scholars, and the irony is that somewhat similar reservations accompanied the reception of modern quantum physics.

  20. Catalytic enantioselective addition of hydrogen cyanide to benzaldehyde and p-methoxybenzaldehyde using cyclo-His-(alpha-Me)Phe as catalyst

    NARCIS (Netherlands)

    Hulst, R; Broxterman, QB; Kamphuis, Johan; Formaggio, F; Crisma, M; Toniolo, C; Kellogg, RM

    1997-01-01

    Two cyclo-dipeptides based on His and the unnatural (alpha Me)Phe have been examined as catalysts in the enantioselective addition of hydrogen cyanide to benzaldehyde and p-methoxy-benzaldehyde. The synthesis, catalytic activity and NMR study towards the mechanism of this reaction are presented. (C)

  1. Catalytic enantioselective addition of hydrogen cyanide to benzaldehyde and p-methoxybenzaldehyde using cyclo-His-(αMe)Phe as catalyst

    NARCIS (Netherlands)

    Hulst, Ron; Broxterman, Quirinus B.; Kamphuis, Johan; Formaggio, Fernando; Crisma, Marco; Toniolo, Claudio; Kellogg, Richard M.

    1997-01-01

    Two cyclo-dipeptides based on His and the unnatural (αMe)Phe have been examined as catalysts in the enantioselective addition of hydrogen cyanide to benzaldehyde and p-methoxy-benzaldehyde. The synthesis, catalytic activity and NMR study towards the mechanism of this reaction are presented.

  2. Catalytic enantioselective addition of hydrogen cyanide to benzaldehyde and p-methoxybenzaldehyde using cyclo-His-(alpha-Me)Phe as catalyst

    NARCIS (Netherlands)

    Hulst, R; Broxterman, QB; Kamphuis, J; Formaggio, F; Crisma, M; Toniolo, C; Kellogg, RM

    1997-01-01

    Two cyclo-dipeptides based on His and the unnatural (alpha Me)Phe have been examined as catalysts in the enantioselective addition of hydrogen cyanide to benzaldehyde and p-methoxy-benzaldehyde. The synthesis, catalytic activity and NMR study towards the mechanism of this reaction are presented. (C)

  3. Effect of initial treatment in the preparation of natural indigo dye from Indigofera tinctoria

    Science.gov (United States)

    Purnama, Herry; Hidayati, Nur; Safitri, Dyah S.; Rahmawati, Sofia

    2017-06-01

    The current tinting industries return to the use of natural dyes because of their characteristics including safe and environmentally friendly. Indonesia can widely promote the potential of natural colours due to the availability of abundant natural dye plants. One of the potential plants that generates blue colour is Indigofera tinctoria. This research was conducted to improve the quality and quantity of natural indigo dye for batik production that supports the environment sustainability. The indigo dark blue paste was produced by initial treatment of soaking in cold water for 48 hours. The 48 hours fermentation anaerobic conditions reached optimum temperature, due to time and pH were also met by nutrients. Aeration was done in ten minutes using an aquarium air pump to increase mixing in water immersion with solution of calcium oxide. Indoxyl in the fermented leaves of Indigofera tinctoria is easily oxidized by air in alkali solution that will form pigment indigo. In that condition, lime (CaO) can be used in the manufacture of indigo paste. In this study, the higher concentrated of blue colour was achieved by lesser amount of lime. The soaking treatment in cold water produced high amount of dyes rather than the initial treatment by both hot water and grounding the indigo leaves. Analysis were done by using UV-Vis Spectrophotometry which showed the value of absorbance. The sample that was soaked in 5 liters of water added by a kilogram of Indigofera tinctoria leaves and 15 grams of lime for 48 hours, obtained the highest absorbance or concentration level. The application of the indigo dyes with or without mordanting agent was also tested for colour fastness.

  4. Preparing our Workforce: Discussing Traditional and Non-Traditional Geoscience Careers - Natural hazard risk

    Science.gov (United States)

    Castaldi, A.

    2013-12-01

    Many young people interested in science think that their only professional opportunities lie within academia or in some government sponsored project. The private sector is often dismissed as not providing the opportunities to a natural scientist or at least an opportunity where they can make a difference. The threat of natural disasters and in the rise of economic losses caused by these disasters as well as the potential problems brought about by climate change have opened up a number of opportunities for the natural scientist. The insurance industry and reinsurance industry is one industry looking for natural scientists and structural engineers. The insurance industry's largest singular threat comes from the risks caused by geological or atmospheric hazards. Over the last decade more and more scientists have used their seismological, hydrological, or weather related knowledge to develop new tools and technology to identify and estimate the economic and social impact due to these natural events. The insurance and reinsurance industry were one of the first industries to call attention to the risk posed by climate change. Our goal is to reduce losses and the cost to insure these losses. Our work starts with the hazard. Hazard identification is one of the best methods for reducing loss nevertheless not all areas of the world have the ability to identify these hazards. Swiss Re transforms science into application. As an example most of the world does not have flood maps to help consumers and policymakers decide which locations are highly exposed and which are not. Swiss Re used a decade of learning to develop a global set of flood maps that identifies the 100 year and 500 year flood zones. To an emerging market these maps will add them in their zoning and building considerations. Academia is a noble profession and the work completed within the university walls is the basis for what we do. Nevertheless the private sector has the ability to use this knowledge and apply

  5. Xanthoceraside hollow gold nanoparticles, green pharmaceutics preparation for poorly water-soluble natural anti-AD medicine.

    Science.gov (United States)

    Meng, Da-Li; Shang, Lei; Feng, Xiao-He; Huang, Xing-Fei; Che, Xin

    2016-06-15

    In order to increase the solubility of poorly water-soluble natural product, xanthoceraside, an effective anti-AD compound from Xanthoceras sorbifolia Bunge, and maintain its natural property, the xanthoceraside hollow gold nanoparticles were successively prepared by green ultrasonic method with silica spheres as templates and HF solution as selective etching solvent. Hollow gold nanoparticles and drug-loaded hollow gold nanoparticles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The solubilities of xanthoceraside loaded on hollow gold nanoparticles were increased obviously from 3.0μg/ml and 2.5μg/ml to 12.7μg/ml and 10.7μg/ml at 25°C and 37°C, respectively. The results of XRD and DSC indicated that the reason for this increase was mainly due to the amorphous state of xanthoceraside loaded on the hollow gold nanoparticles. In summary, the method of loading xanthoceraside onto hollow gold nanoparticles was a green and useful strategy to improve the solubility and dissolution of poorly water-soluble natural products and worth to applying to other natural products. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Electropolymerized fluorinated aniline-based fiber for headspace solid-phase microextraction and gas chromatographic determination of benzaldehyde in injectable pharmaceutical formulations.

    Science.gov (United States)

    Mohammadi, Ali; Mohammadi, Somayeh; Bayandori Moghaddam, Abdolmajid; Masoumi, Vahideh; Walker, Roderick B

    2014-10-01

    In this study, a simple method was developed and validated to detect trace levels of benzaldehyde in injectable pharmaceutical formulations by solid-phase microextraction coupled with gas chromatography-flame ionization detector. Polyaniline was electrodeposited on a platinum wire in trifluoroacetic acid solvent by cyclic voltammetry technique. This fiber shows high thermal and mechanical stability and high performance in extraction of benzaldehyde. Extraction and desorption time and temperature, salt effect and gas chromatography parameters were optimized as key parameters. At the optimum conditions, the fiber shows good linearity between peak area ratio of benzaldehyde/3-chlorobenzaldehyde and benzaldehyde concentration in the range of 50-800 ng/mL with percent relative standard deviation values ranging from 0.75 to 8.64% (n = 3). The limits of quantitation and detection were 50 and 16 ng/mL, respectively. The method has the requisite selectivity, sensitivity, accuracy and precision to assay benzaldehyde in injectable pharmaceutical dosage forms.

  7. Preparation of PES ultrafiltration membranes with natural amino acids based zwitterionic antifouling surfaces

    Science.gov (United States)

    Xu, Chen; Liu, Xiaojiu; Xie, Binbin; Yao, Chen; Hu, Wenhan; Li, Yi; Li, Xinsong

    2016-11-01

    In this report, a simple and facile approach to enhance the antifouling property of poly(ether sulfone) (PES) ultrafiltration membrane was developed by grafting natural amino acids onto surface. First of all, poly(ether sulfone) composite membranes blended with poly(glycidyl methacrylate) were fabricated by phase inversion method followed by grafting of different types of natural amino acids onto the membrane surface through epoxy ring opening reaction. The analysis of attenuated total reflectance Fourier transform infrared spectroscopy (ATR/FTIR) and X-ray photoelectron spectroscopy (XPS) verified the substantial enrichment of amino acids onto the surface of PES membranes. The hydrophilicity of the PES membranes was improved after grafting amino acids. The mechanical property and morphologies of the PES membranes proved that their basic performances were not obviously affected by grafting reaction, and these parameters were all still in the typical range for ultrafiltration membranes. The antifouling property of the grafted PES membranes against bovine serum albumin (BSA) and lysozyme (Lyz) was investigated in detail. It was found that PES membranes incorporated with neutral amino acids exhibited higher fouling resistance to both BSA and Lyz than the parent PES membrane. It can be ascribed to the formation of zwitterionic structure on the surface consisting of protonated secondary amino cations and carboxyl anions. Meanwhile, PES membranes grafted with charged amino acids had better antifouling properties against protein with same electric charges and improved adsorption related to protein with opposite electric charges. Furthermore, the ultrafiltration performance of the zwitterionic PES membranes was evaluated. The results showed that the modified membranes possessed of enhanced pure water flux, relative flux recovery and mildly lower rejection. The Darcy's Law analysis illustrated that the acidic amino acid grafted PES membranes had much lower permeation

  8. Synthesis, spectral and computational analysis of 2-(N-bromoalkoxy)-5-(phenylazo)benzaldehydes and their oximes

    Science.gov (United States)

    Balachander, R.; Manimekalai, A.

    2017-04-01

    2-(N-Bromoalkoxy)-5-(phenylazo)benzaldehydes 1-3, 2-(3-bromomethylbenzyloxy)-5-(phenylazo)benzaldehyde 4 and their oximes 5-8 were synthesized and characterized by FT-IR, GC-MS, 1H, 13C and 2D NMR spectroscopy. The favoured conformations of aldehydes 1-4 and oximes 5-8 were predicted theoretically by geometry optimization and potential energy scan (PES) studies. Selected geometrical parameters and molecular properties such as AIM, NBO, HOMO-LUMO and MEP surfaces were derived from optimized structures. IR, 1H and 13C NMR data were also computed using Gaussian-03 package and compared with the observed values.

  9. Enhancement of reaction rates for catalytic benzaldehyde hydrogenation and sorbitol dehydration in water solvent by addition of carbon dioxide

    Indian Academy of Sciences (India)

    Masayuki Shirai; Osamu Sato; Norihito Hiyoshi; Aritomo Yamaguchi

    2014-03-01

    The effect of pressured carbon dioxide on heterogeneous hydrogenation of benzaldehyde and homogeneous dehydration of sorbitol in water solvent was studied. Initial hydrogenation rates of benzaldehyde over a charcoal-supported palladium catalyst in water at 313 K were enhanced by the addition of carbon dioxide. The initial rate increased with an increase in carbon dioxide pressure and became a maximum at 5 MPa. Dehydration of sorbitol proceeded in water phase at 500 K and initial dehydration rates were enhanced by addition of 30 MPa of carbon dioxide.

  10. Two photon dissociation of benzene, phenylacetylene, and benzaldehyde at 243 nm: translational energy releases in the H atom channel

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Seung Keun; Kim, Hong Lae [Kangwon National Univ., Chuncheon (Korea, Republic of); Park, Chan Ryang [Kookmin Univ., Seoul (Korea, Republic of)

    2002-02-01

    Hydrogen atom production channels from photodissociation of benzene, phenylacetylene, and benzaldehyde at 243 nm have been investigated by detecting H atoms using two photon absorption at 243.2 nm and induced fluorescence at 121.6 nm. Translational energies of the H atoms were measured by Doppler broadened H atom spectra. By absorption of two photons at 243 nm, the H atoms are statistically produced from benzene and phenylacetylene whereas the H atoms from the aldehyde group in benzaldehyde are produced from different pathways. The possible dissociation mechanisms are discussed from the measured translational energy releases.

  11. The effect of solvent on the kinetics of the oxidation of benzaldehydes by quinolinium chlorochromate in aqueous organic solvent media

    Directory of Open Access Journals (Sweden)

    G. FATIMA JEYANTHI

    2002-12-01

    Full Text Available The kinetics of the oxidation of benzaldehyde and para-substituted benzaldehydes by quinolinium chlorochromate in water-dimethylformamide mixtures has been studied under pseudo-first-order conditions at 25±0.2°C. The operation of non-specific and specific solvent-solute interactions was explored by correlating the rate data with solvent parameters through a correlation analysis technique. Both electron-releasing and electron-withdrawing substitutents enhance the rate of oxidation and the Hammett plot shows a break in the reactivity order indicating the applicability of a dual mechanism.

  12. Effects of support and modifiers on catalytic performance of zinc oxide for hydrogenation of methyl benzoate to benzaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Lu Weijing; Lu Guanzhong; Liu Xu; Guo Yanglong; Wang Junsong; Guo Yun

    2003-09-28

    The ZnO supported on {gamma}-Al{sub 2}O{sub 3}, SiO{sub 2}, MCM-41, and {beta}-zeolite were prepared and examined in the hydrogenation of methyl benzoate (MB). ZnO supported on {gamma}-Al{sub 2}O{sub 3} had a higher activity than ZnO. ZnO/{gamma}-Al{sub 2}O{sub 3} modified with 23 ppm lithium had a high catalytic activity (97%) and high selectivity to benzaldehyde (BD, 87%) in a fixed-bed reactor at atmospheric pressure and 400 deg. C. Chromium oxide modified ZnO/{gamma}-Al{sub 2}O{sub 3} also had a high selectivity to BD. Hydrogenolysis of MB occurred over copper modified catalysts. X-ray powder diffraction (XRD) revealed that in the ZnO/{gamma}-Al{sub 2}O{sub 3} catalysts, the ZnO, ZnAl{sub 2}O{sub 4} and {gamma}-Al{sub 2}O{sub 3} phases exited mainly, the border of ZnO and ZnAl{sub 2}O{sub 4} might be important for the hydrogenation of MB to BD. XPS and FT-IR revealed that the chemical environment of ZnO on the ZnO/{gamma}-Al{sub 2}O{sub 3} catalyst is different to ZnO and other supported ZnO catalysts, which gives the ZnO/{gamma}-Al{sub 2}O{sub 3} catalyst having a higher activity than ZnO or ZnO on SiO{sub 2}, MCM-41 or {beta}-zeolite. The presence of third metal (Li, Cr or Cu) oxide in ZnO/{gamma}-Al{sub 2}O{sub 3} could change the electronic structure of Zn and the chemical phenomena of Zn-Al in catalyst and lead to change of the catalytic performance.

  13. The Preparation of Governmental Organizations of Rasht in Dealing with Natural Crises with Emphasis on Crisis Management Components

    Directory of Open Access Journals (Sweden)

    Seyed Ali Hosseini

    2013-10-01

    Full Text Available Increasing of natural disasters over the past decade has led to a catastrophe, due to the large volume of lives and property losses and not having any program. In this context, the appropriate response to these disasters requires planning, forecasting, and using unexpected events prevention methods; the role of governmental organizations is more important as the supporters of citizens.This study aimed to evaluate the status of organizations’ preparation in the field of unexpected events in order to reduce the damage caused by natural disasters and provide effective service. Therefore, the factors affecting the preparation are very important, especially in responsible organizations. This study was a descriptive - analytical research. A number of 50 organizations were assessed in terms of preparedness against disaster. Using a researcher made questionnaire, the data was gathered and analyzed by SPSS. The findings of this study showed that the preparedness of governmental organizations in Rasht has not the necessary capabilities; and there was a significant relationship between the characteristics of organizations and the amount of crisis management components.

  14. Preparation of PES ultrafiltration membranes with natural amino acids based zwitterionic antifouling surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Chen; Liu, Xiaojiu; Xie, Binbin; Yao, Chen [School of Chemistry and Chemical Engineering, Southeast University, Nanjing, 211189 (China); Hu, Wenhan; Li, Yi [Suzhou Faith & Hope Membrane Technology Co., Ltd., Suzhou, 215000 (China); Li, Xinsong, E-mail: lixs@seu.edu.cn [School of Chemistry and Chemical Engineering, Southeast University, Nanjing, 211189 (China)

    2016-11-01

    Highlights: • Amino acids have been successfully grafted onto the surface of PES membranes via amino groups induced epoxy ring opening. • Zwitterionic PES ultrafiltration membranes exhibit excellent antifouling performance and improved permeation properties. • A facile strategy to combat fouling of PES ultrafiltration membranes is developed by grafting natural amino acids. - Abstract: In this report, a simple and facile approach to enhance the antifouling property of poly(ether sulfone) (PES) ultrafiltration membrane was developed by grafting natural amino acids onto surface. First of all, poly(ether sulfone) composite membranes blended with poly(glycidyl methacrylate) were fabricated by phase inversion method followed by grafting of different types of natural amino acids onto the membrane surface through epoxy ring opening reaction. The analysis of attenuated total reflectance Fourier transform infrared spectroscopy (ATR/FTIR) and X-ray photoelectron spectroscopy (XPS) verified the substantial enrichment of amino acids onto the surface of PES membranes. The hydrophilicity of the PES membranes was improved after grafting amino acids. The mechanical property and morphologies of the PES membranes proved that their basic performances were not obviously affected by grafting reaction, and these parameters were all still in the typical range for ultrafiltration membranes. The antifouling property of the grafted PES membranes against bovine serum albumin (BSA) and lysozyme (Lyz) was investigated in detail. It was found that PES membranes incorporated with neutral amino acids exhibited higher fouling resistance to both BSA and Lyz than the parent PES membrane. It can be ascribed to the formation of zwitterionic structure on the surface consisting of protonated secondary amino cations and carboxyl anions. Meanwhile, PES membranes grafted with charged amino acids had better antifouling properties against protein with same electric charges and improved adsorption

  15. Preparation and properties of natural rubber reinforced with polydopamine-coating modified carbon nanotubes

    Directory of Open Access Journals (Sweden)

    Y-L. Lu

    2017-01-01

    Full Text Available Multi-walled carbon nanotubes (MWCNTs were functionalized by polydopamine (PDA-coating and mixed with natural rubber (NR via latex compounding. Compared with pristine MWCNTs, the surface of MWCNT-PDA was covered by an amorphous and nanometer-scale PDA layer which had a large amount of oxygenic and nitric functional groups. So the MWCNT-PDA showed a perfect dispersion in NR matrix. The tensile strength of NR/MWCNT-PDA (5 phr composites is 28.6 MPa, compared with the pure NR, which increased by 42%. For the electrical properties, when the content of MWCNTPDA or MWCNTs is 2 phr, the volume resistivity of NR/MWCNT-PDA composites falls to about 2.7·109 Ω·cm, compared with 3.3·1013 Ω·cm of NR/MWCNT composites. The thermal conductivity of NR composites increased only by 28.2% when 5 phr MWCNT-PDA was added. A model proposed by Nan was used to calculate the thermal conductivity of NR/MWCNT composites, and the calculated values were compared with the experimental values, the results showed that the interface thermal resistance is the main reason why MWCNTs could not significantly increase the thermal conductivity of natural rubber.

  16. A nutrition and conditioning intervention for natural bodybuilding contest preparation: case study.

    Science.gov (United States)

    Robinson, Scott Lloyd; Lambeth-Mansell, Anneliese; Gillibrand, Gavin; Smith-Ryan, Abbie; Bannock, Laurent

    2015-01-01

    Bodybuilding competitions are becoming increasingly popular. Competitors are judged on their aesthetic appearance and usually exhibit a high level of muscularity and symmetry and low levels of body fat. Commonly used techniques to improve physique during the preparation phase before competitions include dehydration, periods of prolonged fasting, severe caloric restriction, excessive cardiovascular exercise and inappropriate use of diuretics and anabolic steroids. In contrast, this case study documents a structured nutrition and conditioning intervention followed by a 21 year-old amateur bodybuilding competitor to improve body composition, resting and exercise fat oxidation, and muscular strength that does not involve use of any of the above mentioned methods. Over a 14-week period, the Athlete was provided with a scientifically designed nutrition and conditioning plan that encouraged him to (i) consume a variety of foods; (ii) not neglect any macronutrient groups; (iii) exercise regularly but not excessively and; (iv) incorporate rest days into his conditioning regime. This strategy resulted in a body mass loss of 11.7 kg's, corresponding to a 6.7 kg reduction in fat mass and a 5.0 kg reduction in fat-free mass. Resting metabolic rate decreased from 1993 kcal/d to 1814 kcal/d, whereas resting fat oxidation increased from 0.04 g/min to 0.06 g/min. His capacity to oxidize fat during exercise increased more than two-fold from 0.24 g/min to 0.59 g/min, while there was a near 3-fold increase in the corresponding exercise intensity that elicited the maximal rate of fat oxidation; 21% V̇O2max to 60% V̇O2max. Hamstring concentric peak torque decreased (1.7 to 1.5 Nm/kg), whereas hamstring eccentric (2.0 Nm/kg to 2.9 Nm/kg), quadriceps concentric (3.4 Nm/kg to 3.7 Nm/kg) and quadriceps eccentric (4.9 Nm/kg to 5.7 Nm/kg) peak torque all increased. Psychological mood-state (BRUMS scale) was not negatively influenced by the intervention and all values relating to the Athlete

  17. Development of naturally activated edible films with antioxidant properties prepared from red seaweed Porphyra columbina biopolymers.

    Science.gov (United States)

    Cian, Raúl E; Salgado, Pablo R; Drago, Silvina R; González, Rolando J; Mauri, Adriana N

    2014-03-01

    The aim of this work was to study the physicochemical and antioxidant properties of phycobiliproteins-phycocolloids-based films, obtained from mixtures of two aqueous fractions extracted from Porphyra columbina red seaweed, one enriched in phycocolloids (PcF) and the other in phycobiliproteins (PF). Films with different ratios of PF:PcF (0, 25, 50, 75, 100% [w/w]) and without plasticizer addition were prepared by casting. PcF films had excellent mechanical properties (tensile strength ∼50MPa, elongation at break ∼3% and an elastic modulus ∼17.5MPa). The addition of PF to formulations exerted a plasticizing effect on the PcF matrix, which was manifested in moisture content, water solubility and mechanical properties of the resulting films but not in its water vapour permeability. The antioxidant capacity (TEAC) of the PcF films was significantly increased by the addition of PF and a direct relationship between TEAC and the total phenolic compounds (r(2)=0.9998) and R-phycoerythrin (r(2)=0.9942) was observed.

  18. Effect of benzaldehyde on the electrodeposition and corrosion properties of Ni-W alloys

    Science.gov (United States)

    Pramod Kumar, U.; Kennady, C. Joseph

    2015-10-01

    The effect of different concentrations of benzaldehyde on the electrodeposition of Ni-W alloy coatings on a mild steel substrate from a citrate electrolyte was investigated in this study. The electrolytic alkaline bath (pH 8.0) contained stoichiometric amounts of nickel sulfate, sodium tungstate, and trisodium citrate as precursors. The corrosion resistance of the Ni-W-alloy-coated specimens in 0.2 mol/L H2SO4 was studied using various electrochemical techniques. Tafel polarization studies reveal that the alloy coatings obtained from the bath containing 50 ppm benzaldehyde exhibit a protection efficiency of 95.33%. The corrosion rate also decreases by 21.5 times compared with that of the blank. A higher charge-transfer resistance of 1159.40 Ω·cm2 and a lower double-layer capacitance of 29.4 μF·cm-2 further confirm the better corrosion resistance of the alloy coating. X-ray diffraction studies reveal that the deposits on the mild steel surface are consisted of nanocrystals. A lower surface roughness value ( R max) of the deposits is confirmed by atomic force microscopy.

  19. Growth of 4-(dimethylamino) benzaldehyde doped triglycine sulphate single crystals and its characterization

    Energy Technology Data Exchange (ETDEWEB)

    Rai, Chitharanjan, E-mail: raichitharanjan@gmail.co [Department of Physics, Mangalore University, Mangalagangotri 574 199 (India); Kalpataru First Grade Science College, Tiptur 572 202 (India); Sreenivas, K. [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Dharmaprakash, S.M., E-mail: smdharma@yahoo.co [Department of Physics, Mangalore University, Mangalagangotri 574 199 (India)

    2009-11-15

    Single crystals of triglycine sulphate (TGS) doped with 1 mol% of 4-(dimethylamino) benzaldehyde (DB) have been grown from aqueous solution at ambient temperature by slow evaporation technique. The effect of dopant on the crystal growth and dielectric, pyroelectric and mechanical properties of TGS crystal have been investigated. X-ray powder diffraction pattern for pure and doped TGS was collected to determine the lattice parameters. FTIR spectra were employed to confirm the presence of 4-(dimethylamino) benzaldehyde in TGS crystal, qualitatively. The dielectric permittivity has been studied as a function of temperature by cooling the sample at a rate of 1 deg. C/min. An increase in the Curie temperature T{sub c}=51 deg. C (for pure TGS, T{sub c}=48.5 deg. C) and decrease in maximum permittivity has been observed for doped TGS when compared to pure TGS crystal. Pyroelectric studies on doped TGS were carried out to determine pyroelectric coefficient. The Vickers's hardness of the doped TGS crystals along (0 1 0) face is higher than that of pure TGS crystal for the same face. Domain patterns on b-cut plates were observed using scanning electron microscope. The low dielectric constant, higher pyroelectric coefficient and higher value of hardness suggest that doped TGS crystals could be a potential material for IR detectors.

  20. Stereocontrol of the Schiff Base of Substituted Benzaldehyde to Staudinger Cycloaddition Reaction

    Institute of Scientific and Technical Information of China (English)

    齐传民; 杨凌春; 孙彭利

    2003-01-01

    Syntheses of 4 novel chiral azetidin-2-one derivatives,which were characterized by 1H NMR,IR,specific rotation and elemental analysis,through Staudinger cycloaddition reaction of Schiff base of benzaldehyde with chlorine substitution at different position in benzene ring,were described.For the first time,this type of 3S,4R configuration azetidin-2-one monocrystals with many chiral centers [(3S,4R)-3-hydroxy-N-[(S)-(1-phenyl)ethyl]-4-(2''-chlorophenyl)-azetidin-2-one monocrystal]were obtained,the structures of which were determined by X-ray diffraction analysis.The effects of Schiff base of benzaldehyde with chlorine substitution at different position in benzene ring on stereoselectivity of Staudinger cycloaddition reaction products were discussed and the results are showed as below:2-chlorophenyl Schiff base favored to yield 3S,4R configuration product,but 4-chlorophenyl Schiff base favored to yield 3R,4S configuration product.The reaction orientation of 2,4-dichlorophenyl Schiff base was determined by corporate effect of 2- and 4-chlorine,and that of the 4-chlorine was more obvious.In contrast to 4-chlorophenyl,although the main product was 3R,4S configuration,3-chlorophenyl owned lower selectivity.

  1. Benzoxyl radical decomposition kinetics: formation of benzaldehyde + H, phenyl + CH2O, and benzene + HCO.

    Science.gov (United States)

    da Silva, Gabriel; Bozzelli, Joseph W

    2009-06-25

    The kinetics of benzoxyl radical decomposition was studied using ab initio computational chemistry and RRKM rate theory. The benzoxyl radical is an important but short-lived intermediate in the combustion of toluene and other alkylated aromatic hydrocarbons. A theoretical study of the thermochemistry and kinetics to products over a range of temperatures and pressures for benzoxyl decomposition is reported. Ab initio calculations with the G3X theoretical method reveal low-energy pathways from the benzoxyl radical to benzaldehyde + H and the phenyl radical + formaldehyde (CH(2)O), as well as a novel mechanism to benzene + the formyl radical (HC(*)O). RRKM simulations were performed for benzoxyl decomposition as a function of temperature and pressure. Benzaldehyde formation constitutes more than 80% of the total reaction products at temperatures below 1000 K, decreasing to around 50% at 2000 K. Formation of benzene + HC(*)O and phenyl + CH(2)O is of similar importance, each accounting for 5-10% of the decomposition products at around 1000 K, increasing to 20-30% at 2000 K. The results presented here should lead to improved kinetic models for the oxidation of alkylated aromatic hydrocarbons, particularly for the formation of benzene as a direct oxidation product of toluene. Re-evaluation of the phenyl radical heat of formation leads us to suggest a benzene C-H bond dissociation energy in the range of 113.5-114.5 kcal mol(-1).

  2. Coupled electron and proton transfer processes in 4-dimethylamino-2-hydroxy-benzaldehyde.

    Science.gov (United States)

    Zgierski, Marek Z; Fujiwara, Takashige; Lim, Edward C

    2011-09-08

    TDDFT calculations, picosecond transient absorption, and time-resolved fluorescence studies of 4-dimethylamino-2-hydroxy-benzaldehyde (DMAHBA) have been carried out to study the electron and proton transfer processes in polar (acetonitrile) and nonpolar (n-hexane) solvents. In n-hexane, the transient absorption (TA) as well as the fluorescence originate from the ππ* state of the keto form (with the carbonyl group in the benzaldehyde ring), which is produced by an intramolecular proton transfer from the initially excited ππ* state of the enol form (OH group in the ring). The decay rate of TA and fluorescence are essentially identical in n-hexane. In acetonitrile, on the other hand, the TA exhibits features that can be assigned to the highly polar twisted intramolecular charge transfer (TICT) states of enol forms, as evidenced by the similarity of the absorption to the TICT-state absorption spectra of the closely related 4-dimethylaminobenzaldehyde (DMABA). As expected, the decay rate of the TICT-state of DMAHBA is different from the fluorescence lifetime of the ππ* state of the keto form. The occurrence of the proton and electron transfers in acetonitrile is in good agreement with the predictions of the TDDFT calculations. The very short-lived (∼1 ps) fluorescence from the ππ* state of the enol form has been observed at about 380 nm in n-hexane and at about 400 nm in acetonitrile.

  3. Investigation of the l-phenylacetylcarbinol process to substituted benzaldehydes of interest.

    Science.gov (United States)

    Maroney, Kerrie Anne N; Culshaw, Peter N; Wermuth, Urs D; Cresswell, Sarah L

    2014-02-01

    The large scale industrial manufacture of the nasal decongestant pseudoephedrine is typically carried out by the reductive amination of l-phenylacetylcarbinol (l-PAC), which in turn is produced via the biotransformation of benzaldehyde using yeast. In recent years there has been increasing legislative control of the supply of pseudoephedrine due to it being diverted for the clandestine production of methylamphetamine and there is some evidence that a number of clandestine drug laboratory chemists have considered the application of the l-PAC process to manufacture their own pseudoephedrine. This work examined the use of a number of substituted benzaldehydes for the manufacture of the corresponding substituted l-PAC analogue followed by reductive amination to the corresponding substituted pseudoephedrine/ephedrine analogues. These substituted pseudoephedrine/ephedrine analogues were either reduced or oxidised to determine the feasibility of producing the corresponding methylamphetamine or methcathinone analogues. As a result, the l-PAC process was identified as a viable route for synthesis of substituted methylamphetamines and methcathinones. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  4. Effect of benzaldehyde on the electrodeposition and corrosion properties of Ni–W alloys

    Institute of Scientific and Technical Information of China (English)

    U. Pramod Kumar; C. Joseph Kennady

    2015-01-01

    The effect of different concentrations of benzaldehyde on the electrodeposition of Ni–W alloy coatings on a mild steel substrate from a citrate electrolyte was investigated in this study. The electrolytic alkaline bath (pH 8.0) contained stoichiometric amounts of nickel sulfate, sodium tungstate, and trisodium citrate as precursors. The corrosion resistance of the Ni–W-alloy-coated specimens in 0.2 mol/L H2SO4 was studied using various electrochemical techniques. Tafel polarization studies reveal that the alloy coatings obtained from the bath containing 50 ppm benzaldehyde exhibit a protection efficiency of 95.33%. The corrosion rate also decreases by 21.5 times compared with that of the blank. A higher charge-transfer resistance of 1159.40?·cm2 and a lower double-layer capacitance of 29.4 μF·cm?2 further confirm the better corrosion resistance of the alloy coating. X-ray diffraction studies reveal that the deposits on the mild steel surface are consisted of nanocrystals. A lower surface roughness value (Rmax) of the deposits is confirmed by atomic force microscopy.

  5. Purification and characterization of benzyl alcohol- and benzaldehyde- dehydrogenase from Pseudomonas putida CSV86.

    Science.gov (United States)

    Shrivastava, Rahul; Basu, Aditya; Phale, Prashant S

    2011-08-01

    Pseudomonas putida CSV86 utilizes benzyl alcohol via catechol and methylnaphthalenes through detoxification pathway via hydroxymethylnaphthalenes and naphthaldehydes. Based on metabolic studies, benzyl alcohol dehydrogenase (BADH) and benzaldehyde dehydrogenase (BZDH) were hypothesized to be involved in the detoxification pathway. BADH and BZDH were purified to apparent homogeneity and were (1) homodimers with subunit molecular mass of 38 and 57 kDa, respectively, (2) NAD(+) dependent, (3) broad substrate specific accepting mono- and di-aromatic alcohols and aldehydes but not aliphatic compounds, and (4) BADH contained iron and magnesium, while BZDH contained magnesium. BADH in the forward reaction converted alcohol to aldehyde and required NAD(+), while in the reverse reaction it reduced aldehyde to alcohol in NADH-dependent manner. BZDH showed low K (m) value for benzaldehyde as compared to BADH reverse reaction. Chemical cross-linking studies revealed that BADH and BZDH do not form multi-enzyme complex. Thus, the conversion of aromatic alcohol to acid is due to low K (m) and high catalytic efficiency of BZDH. Phylogenetic analysis revealed that BADH is a novel enzyme and diverged during the evolution to gain the ability to utilize mono- and di-aromatic compounds. The wide substrate specificity of these enzymes enables strain to detoxify methylnaphthalenes to naphthoic acids efficiently.

  6. Advanced sample preparation for the molecular quantification of Staphylococcus aureus in artificially and naturally contaminated milk.

    Science.gov (United States)

    Aprodu, Iuliana; Walcher, Georg; Schelin, Jenny; Hein, Ingeborg; Norling, Börje; Rådström, Peter; Nicolau, Anca; Wagner, Martin

    2011-03-01

    Sample treatment is an essential element when using real-time PCR for quantification of pathogens directly on food samples. This study comparatively evaluated three different principles of sample treatment, i.e. immunomagnetic separation based on phage-derived cell wall binding molecules, matrix solubilization and flotation, in order to establish their suitability for quantifying low numbers of Staphylococcus aureus in milk. All three procedures succeeded to remove S. aureus from the milk matrix, either raw or pasteurized, and, as a result of the concentration of the target cells, minimized the effect of milk associated PCR inhibitors. Sample preparation based on immunomagnetic separation albeit of being user friendly, specific and rapid, failed to allow quantification of low and medium numbers (<10(4)CFU) of S. aureus. In a mastitic milk model cell wall binding domain (CBD)-based target cell extraction revealed results most closely matching those derived from culture-based quantification. Both matrix lysis and flotation allowed quantification of S. aureus at a level of 1-10 cells per ml. Both methods resulted in higher numbers of bacterial cell equivalents (bce) than plating could reveal. Since both methods harvest cells that have been subjected to either mechanical and chemical stresses before quantification, we concluded that the higher bce numbers resulted from a disaggregation of S. aureus clusters initially present in the inoculum. Conclusively, since likely each S. aureus cell of a toxigenic strain contributes to enterotoxin production, molecular quantification could provide an even more realistic impact assessment in outbreak investigations than plating does.

  7. Preparation of Silver Nanoparticles from Synthetic and Natural Sources: Remediation Model for PAHs

    Science.gov (United States)

    Abbasi, Maryam; Saeed, Fatima; Rafique, Uzaira

    2014-06-01

    The emergence of nanoscience and technology is gaining popularity with an increasing demand for metal nanoparticles applicability in various areas such as electronics, catalysis, chemistry, energy and medicine. Metallic nanoparticles are traditionally synthesized by wet chemical techniques, where the chemicals used are quite often toxic and flammable. In this work, an attempt is made to compare the efficiency of two different synthesis methods and application of each for the remediation of poly aromatic hydrocarbons (PAHs). In this regard, silver nanoparticles are prepared by green and wet chemical method using plant extract of garlic (Allium sativum). The extract is known to reduce the metal during synthesis and acts as stabilizing ligand. These synthesized silver nanoparticles (Agp) and (AgW) were applied as adsorbents in synthetic batch mode experiments at varying parameters of pH and temperature. A concentration of 0.01mg/L of Phenanthrene, Anthracene, and Pyrene were induced at fixed dosage of 1mg/Kg of adsorbent. Residual concentration of each PAH was analyzed on UV-Visible spectrophotometer. The results indicated that both adsorbents follow the sequence of Phenanthrene>Pyrene>Anthracene with optimal removal of higher than 85% in each case. A distinguishing privilege is attained by Agp adsorbent showing 3, 3 and 11 orders of magnitude higher efficiency than Agw. It may be attributed to more functional groups in the plant extract participating in binding of PAH to the surface. Each synthesized adsorbents was characterized by FTIR, SEM and EDX. The average particle size was determined to be of the order of 13-26 nm. The study concludes the use of alternate economical and green adsorbents for control of poly aromatic hydrocarbons (PAHs).

  8. Sintering and dielectric properties of a technical porcelain prepared from economical natural raw materials

    Energy Technology Data Exchange (ETDEWEB)

    Kasrani, S.; Harabi, A.; Barama, S.-E.; Foughali, L.; Benhassine, M. T., E-mail: souad478@yahoo.fr, E-mail: harabi52@gmail.com, E-mail: sebarama@usa.com, E-mail: foughali_lazhar@yahoo.fr, E-mail: mtb25dz@gmail.com [Ceramics Lab. Mentouri University of Constantine (Algeria); Aldhayan, D.M., E-mail: aldhayan@ksu.edu.sa [Chemistry Department, Riyadh, King Saud University (Saudi Arabia)

    2016-10-15

    In this study, the production of a technical porcelain, for the ceramic dielectric applications by using economical natural raw materials, was investigated. The basic porcelain composition was selected consisting of 30 wt% kaolin, 45 wt% potash-feldspar and 25 wt% quartz. The obtained phases in the sintered samples were investigated by X-ray diffraction, Fourier transform infrared spectroscopy analysis, and scanning electron microscopy images. It has been confirmed by these techniques that the main crystalline phases were quartz and mullite. Dielectric measurements of technical porcelains have been carried out at 1 kHz from room temperature to 200 °C. The dielectric constant, loss factor, dielectric loss tangent, and resistivity of the porcelain sample sintered at 1160 °C were 22-25, 0.32-1.80, 0.006-0.07, and 0.2-9 x 10{sup 13} Ω.cm, respectively. The value of dielectric constant was significantly high when compared to that of conventional porcelains which did not exceed generally 9. (author)

  9. Systems Education for a Sustainable Planet: Preparing Children for Natural Disasters

    Directory of Open Access Journals (Sweden)

    Kevin R. Ronan

    2014-01-01

    Full Text Available This paper first reviews research linked to the United Nations International Strategy for Disaster Reduction focusing on “child-centred disaster risk reduction” (CC-DRR, highlighting systemic aspects of disaster prevention and preparedness educational programming to date. However, it is also pointed out that education evaluated to date largely assumes a linear, mechanistic approach to preparedness and related resiliency outcomes. Thus, the main thrust of this paper is to elucidate means by which hazards and disaster preparedness education programs for children can shift to systems-based models, those that incorporate both systemic epistemologies but also more systems-based, and interconnected, curricula. This includes curricula that help children connect the physical world and science with the social world and human factors. It also includes the more systemic idea that natural hazards are but one example of a larger category of problems in life related to risk and uncertainty. Thus, a main aim of a systems educational approach is to help children equip themselves with knowledge, skills, motivation and confidence that they can increasingly manage a range of risks in life. This includes an increasing understanding of the added value that can be gained from approaching problems with systemic tools, including producing increasingly effective and sustainable solutions to what public policy refers to as wicked problems.

  10. Sintering and dielectric properties of a technical porcelain prepared from economical natural raw materials

    Directory of Open Access Journals (Sweden)

    S. Kasrani

    Full Text Available Abstract In this study, the production of a technical porcelain, for the ceramic dielectric applications by using economical natural raw materials, was investigated. The basic porcelain composition was selected consisting of 30 wt% kaolin, 45 wt% potash-feldspar and 25 wt% quartz. The obtained phases in the sintered samples were investigated by X-ray diffraction, Fourier transform infrared spectroscopy analysis, and scanning electron microscopy images. It has been confirmed by these techniques that the main crystalline phases were quartz and mullite. Dielectric measurements of technical porcelains have been carried out at 1 kHz from room temperature to 200 °C. The dielectric constant, loss factor, dielectric loss tangent, and resistivity of the porcelain sample sintered at 1160 °C were 22-25, 0.32-1.80, 0.006-0.07, and 0.2-9 x 1013 Ω.cm, respectively. The value of dielectric constant was significantly high when compared to that of conventional porcelains which did not exceed generally 9.

  11. Search for Antiprotozoal Activity in Herbal Medicinal Preparations; New Natural Leads against Neglected Tropical Diseases.

    Science.gov (United States)

    Llurba Montesino, Núria; Kaiser, Marcel; Brun, Reto; Schmidt, Thomas J

    2015-08-04

    Sleeping sickness, Chagas disease, Leishmaniasis, and Malaria are infectious diseases caused by unicellular eukaryotic parasites ("protozoans"). The three first mentioned are classified as Neglected Tropical Diseases (NTDs) by the World Health Organization and together threaten more than one billion lives worldwide. Due to the lack of research interest and the high increase of resistance against the existing treatments, the search for effective and safe new therapies is urgently required. In view of the large tradition of natural products as sources against infectious diseases [1,2], the aim of the present study is to investigate the potential of legally approved and marketed herbal medicinal products (HMPs) as antiprotozoal agents. Fifty-eight extracts from 53 HMPs on the German market were tested by a Multiple-Target-Screening (MTS) against parasites of the genera Leishmania, Trypanosoma, and Plasmodium. Sixteen HMPs showed in vitro activity against at least one of the pathogens (IC50 Arnica, and Curcuma exhibited high activity (IC50 < 2.5 µg/mL). They were analytically characterized by UHPLC/ESI-QqTOF-MSMS and the activity-guided fractionation of the extracts with the aim to isolate and identify the active compounds is in progress.

  12. A rational design for the nanoencapsulation of poisonous animal venoms in liposomes prepared with natural phospholipids.

    Science.gov (United States)

    da Costa, Maria Helena Bueno; Sant'Anna, Osvaldo A; Quintilio, Wagner; Schwendener, Reto Albert; de Araujo, Pedro Soares

    2012-11-01

    Liposomes have been used since the 1970's to encapsulate drugs envisaging enhancement in efficacy and therapeutic index, avoidance of side effects and increase in the encapsulated agent stability. The major problem when encapsulating snake venoms is the liposomal membrane instability caused by venom phospholipases. Here the results obtained encapsulating Crotalus durissimus terrificus and a pool of Bothropic venoms within liposomes (LC and LB, respectively) used to produce anti-venom sera are presented. The strategy was to modify the immunization protocol to enhance antibody production and to minimize toxic effects by encapsulating inactivated venoms within stabilized liposomes. Chemically modified venoms were solubilized in a buffer containing an inhibitor and a chelating agent. The structures of the venoms were analyzed by UV, CD spectroscopy and ELISA. In spite of the differences in the helical content between natural and modified venoms, they were recognized by horse anti-sera. To maintain long-term stability, mannitol was used as a cryoprotectant. The encapsulation efficiencies were 59 % (LB) and 99 % (LC), as followed by filtration on Sephacryl S1000. Light scattering measurements led us to conclude that both, LB (119 ±47 nm) and LC (147±56 nm) were stable for 22 days at 4 °C, even after lyophilization. Genetically selected mice and mixed breed horses were immunized with these formulations. The animals did not show clinical symptoms of venom toxicity. Both, LB and LC enhanced by at least 30 % the antibody titers 25 days after injection and total IgG titers remained high 91 days after immunization. The liposomal formulation clearly exhibited adjuvant properties.

  13. THE PREPARATION OF MAGNETICALLY MODIFIED SYNTHETETIC AND NATURAL ZEOLITES AND COMPARISON OF THEIR SOME PHYSICAL PROPERTIES

    Directory of Open Access Journals (Sweden)

    Zafer DİKMEN

    2013-06-01

    Full Text Available In this study, magnetically modified zeolites (MMZ has been produced and their adsorption, ion-exchange and magnetic properties have been studied. In this study, natural zeolite mineral, clinoptilolite, which belongs to Gördes (Manisa regions and synthetic 13X zeolite, which has been produced by Sigma-Aldrich firm have been used. In order to modify the surface of these minerals, magnetite sample which belongs to Divriği (Sivas region has been used. The engagement of magnetite particles on zeolite particles has been studied. For this reason, measuring, visualization and analysis techniques as DTA-TG, XRD, XRF, SEM and EDX have been used. As a result of these procedures, it has been observed that magnetite particles get engaged on the surface of zeolite particles and magnetite contribu-tion on MMZ has changed adsorption, ion-exchange and magnetic properties.In order to determine how magnetite contribution affects adsorption, ion exchange and magnetic properties of MMZ, weightily magnetite contribution ratio (zeolite/magnetite has been applied in three different forms (1/1, 1/2, 1/3.As a result of nitrogen adsorption of MMZ, it has been observed that as the weightily magnetite contribution ratio goes up, specific surface area goes down and average pore diameter rises. It has been identified that total cation exchange capacity rises as the weightily magnetite contribution ratio goes up. It has been observed that pure zeolites, which have no magnetic properties, as a result of magnetically modification process, they have got magnetically character, and they change their magnetic properties positively as the weightily magnetite contribution goes up. It has been determined that as a result of magnetic measurements; the optimum value of applied outer magnetic field is 0.5T.

  14. Targeted drug delivery potential of hydrogel biocomposites containing partially and thermally reduced graphene oxide and natural polymers prepared via green process

    CSIR Research Space (South Africa)

    Aderibigbe, BA

    2015-10-01

    Full Text Available Hydrogel biocomposites containing a combination of partially and thermally reduced graphene oxide (rGO) and natural polymer were prepared by free radical polymerization. The effect of rGO and the natural polymer on the morphology of the hydrogel...

  15. Quantification of brown dog tick repellents, 2-hexanone and benzaldehyde, and release from tick-resistant beagles, Canis lupus familiaris

    Science.gov (United States)

    We have recently shown that repellency of the tick Rhipicephalus sanguineus sensu lato by the tick resistant dog breed Beagle is mediated by volatile organic compounds 2-hexanone and benzaldehyde present in Beagle dog odour. Ectoparasite location on animal hosts is affected by variation in odour com...

  16. Production of the flavor compound benzaldehyde by lactic acid bacteria: role of manganese and its transport systems in Lactobacillus plantarum

    NARCIS (Netherlands)

    Nierop Groot, M.N.

    2001-01-01

    One of the aims of the research described in this thesis (Chapter 1 and 2) was to investigate the conversion of phenylalanine to the aromatic flavor compound benzaldehyde in lactic acid bacteria (LAB) (Chapter 3). Lactobacillus plantarum was used as the model organism to study p

  17. Kinetic evaluation of biotransformation of benzaldehyde to L-phenylacetylcarbinol by immobilized pyruvate decarboxylase from Candida utilis.

    Science.gov (United States)

    Shin, H S; Rogers, P L

    1996-02-20

    Biotransformation of benzaldehyde to L-phenylacetylcarbinol (L-PAC) as a key intermediate for L-ephedrine has been evaluated using immobilized pyruvate decarboxylase (PDC) from Candida utilis. PDC immobilized in spherical polyacrylamide beads was found to have a longer half-life compared with free enzyme. In a batch process, the immobilized PDC generally produced lower L-PAC than free enzyme at the same concentrations of substrates due to increased by-products acetaldehyde and acetoin and reduced benzaldehyde uptake. With immobilized PDC, L-PAC formation occurred at higher benzaldehyde concentrations (up to 300 mM) with the highest L-PAC concentration being 181 mM (27.1 g/L). For a continuous process, when 50 mM benzaldehyde and 100 mM sodium pyruvate were fed into a packed-bed reactor at 4 degrees C and pH 6.5, a productivity of 3.7 mM/h (0.56 g/L . h) L-PAC was obtained at an average concentration of 30 mM (4.5 g/L). The half-life of immobilized PDC reactor was 32 days. (c) 1996 John Wiley & Sons, Inc.

  18. Production of the flavor compound benzaldehyde by lactic acid bacteria: role of manganese and its transport systems in Lactobacillus plantarum

    NARCIS (Netherlands)

    Nierop Groot, M.N.

    2001-01-01

    One of the aims of the research described in this thesis (Chapter 1 and 2) was to investigate the conversion of phenylalanine to the aromatic flavor compound benzaldehyde in lactic acid bacteria (LAB) (Chapter 3). Lactobacillus plantarum was used as the model organism to study phenylalanine degradat

  19. Production of the flavor compound benzaldehyde by lactic acid bacteria: role of manganese and its transport systems in Lactobacillus plantarum

    NARCIS (Netherlands)

    Nierop Groot, M.N.

    2001-01-01

    One of the aims of the research described in this thesis (Chapter 1 and 2) was to investigate the conversion of phenylalanine to the aromatic flavor compound benzaldehyde in lactic acid bacteria (LAB) (Chapter 3). Lactobacillus plantarum was used as the model organism to study

  20. Benzaldehyde thiosemicarbazone

    Directory of Open Access Journals (Sweden)

    Xiu-Ping Ju

    2008-12-01

    Full Text Available The title compound, C8H9N3S, contains two molecules in the asymmetric unit. One molecule is close to being planar (r.m.s. deviation from the mean plane = 0.06 Å for the non-H atoms, while the other exhibits a dihedral angle of 21.7 (1° between the benzene ring and the mean plane of the thiosemicarbazone unit. Intermolecular N—H...S hydrogen bonds link the molecules into layers parallel to the (010 plane.

  1. 天然甲酸和甲酸乙酯的制备%Preparation of Natural Formic Acid and Ethyl Formate

    Institute of Scientific and Technical Information of China (English)

    谷运璀; 钱婉珠; 张民; 吴征兵

    2013-01-01

    The preparation method of natural formic acid by oxidation of glucose was investigated,and natural ethyl formate was prepared by the esterification of obtained natural formic acid and ethanol that produced from cereal fermentation as well.%研究利用葡萄糖氧化制备天然甲酸的方法,并采用发酵乙醇与天然甲酸发生酯化反应制备香料工业用天然甲酸乙酯.

  2. Preparation and characterization of nanocomposites of natural rubber with polystyrene and styrene-methacrylic acid copolymer nanoparticles

    Directory of Open Access Journals (Sweden)

    T. Nuruk

    2012-06-01

    Full Text Available Composites of natural rubber (NR/vinyl polymer nanoparticles as polystyrene (PS and poly(styrenemethacrylic acid (P(S-MAA were prepared by heterocoagulation technique. The polymer nanoparticles were prepared by emulsifier-free emulsion polymerizations at 70°C using potassium persulfate as initiator. Under acidic condition where positive charge was present on the NR latex (NRL surface, the nanoparticles having negative charge mainly from sulfate group of initiator were able to adsorb on the NRL surface, the electrostatic interaction being the driving force. The scanning electron micrographs showed that the polymer nanoparticles are homogenously distributed throughout NR matrix as nanoclusters with an average size of about 500 and 200 nm for PS and P(S-MAA, respectively. The mechanical properties of NR/PS and NR/P(S-MAA composite films were compared with the NR host. The nanocomposites, particularly when the polymer nanoparticles are uniformly dispersed, possess significantly enhanced mechanical properties strongly depending on the morphology of the nanocomposites.

  3. 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

  4. Natural lactic acid bacteria population of tropical grasses and their fermentation factor analysis of silage prepared with cellulase and inoculant.

    Science.gov (United States)

    Khota, Waroon; Pholsen, Suradej; Higgs, David; Cai, Yimin

    2016-12-01

    Natural lactic acid bacteria (LAB) populations in tropical grasses and their fermentation characteristics on silage prepared with cellulase enzyme and LAB inoculants were studied. A commercial inoculant Lactobacillus plantarum Chikuso 1 (CH), a local selected strain Lactobacillus casei TH14 (TH14), and 2 cellulases, Acremonium cellulase (AC) and Maicelase (MC; Meiji Seika Pharma Co. Ltd., Tokyo, Japan), were used as additives to silage preparation with fresh and wilted (6 h) Guinea grass and Napier grass. Silage was prepared using a laboratory-scale fermentation system. Treatments were CH, TH14, AC at 0.01% fresh matter, AC 0.1%, MC 0.01%, MC 0.1%, CH+AC 0.01%, CH+AC 0.1%, CH+MC 0.01%, CH+MC 0.1%, TH14+AC 0.1%, TH14+AC 0.01%, TH14+MC 0.1%, and TH14+MC 0.01%. Microorganism counts of Guinea grass and Napier grass before ensiling were 10(2) LAB and 10(6) aerobic bacteria; these increased during wilting. Based on morphological and biochemical characteristics, and 16S rRNA gene sequence analysis, natural strains from both grasses were identified as L. plantarum, L. casei, Lactobacillus acidipiscis, Leuconostoc pseudomesenteroides, Leuconostoc garlicum, Weissella confusa, and Lactococcus lactis. Lactobacillus plantarum and L. casei are the dominant species and could grow at lower pH and produce more lactic acid than the other isolates. Crude protein and neutral detergent fiber were 5.8 and 83.7% of dry matter (DM) for Guinea grass, and 7.5 and 77.1% of DM for Napier grass. Guinea grass had a low level of water-soluble carbohydrates (0.39% of DM). Guinea grass silage treated with cellulase had a lower pH and higher lactic acid content than control and LAB treatments. The 0.1% AC and MC treatments had the best result for fermentation quality. All high water-soluble carbohydrate (2.38% DM) Napier grass silages showed good fermentation quality. Compared with control and LAB-inoculated silage, the cellulase-treated silages had significantly higher crude protein content and

  5. Mimicking natural superhydrophobic surfaces and grasping the wetting process: a review on recent progress in preparing superhydrophobic surfaces.

    Science.gov (United States)

    Yan, Y Y; Gao, N; Barthlott, W

    2011-12-12

    A typical superhydrophobic (ultrahydrophobic) surface can repel water droplets from wetting itself, and the contact angle of a water droplet resting on a superhydrophobic surface is greater than 150°, which means extremely low wettability is achievable on superhydrophobic surfaces. Many superhydrophobic surfaces (both manmade and natural) normally exhibit micro- or nanosized roughness as well as hierarchical structure, which somehow can influence the surface's water repellence. As the research into superhydrophobic surfaces goes deeper and wider, it is becoming more important to both academic fields and industrial applications. In this work, the most recent progress in preparing manmade superhydrophobic surfaces through a variety of methodologies, particularly within the past several years, and the fundamental theories of wetting phenomena related to superhydrophobic surfaces are reviewed. We also discuss the perspective of natural superhydrophobic surfaces utilized as mimicking models. The discussion focuses on how the superhydrophobic property is promoted on solid surfaces and emphasizes the effect of surface roughness and structure in particular. This review aims to enable researchers to perceive the inner principles of wetting phenomena and employ suitable methods for creation and modification of superhydrophobic surfaces. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Preparation of molecular sieve from natural pyrophyllite and characterization of its Al/Si ratio, crystal structure, and Porosity

    Science.gov (United States)

    Idiawati, Riris; Fuad, Abdulloh; Mufti, Nandang; Hartatiek; Bahtiar, Syamsul; Subakti; Taufiq, Ahmad

    2017-05-01

    Pyrophyllite is one abundant mineral in Indonesia which has not been optimally processed. Hence, this study further processed natural pyrophyllite to be an advanced material usable for industrial sector as a molecular sieve (MS). Natural pyrophyllitewas chosen due to its ability to filter gas or liquid selectively. The MS made from natural pyrophyllite was prepared by using a simple method, in short time and with less cost via leaching process. NaOH was varied to 10 M (MS1), 15 M (MS2), and 20 M (MS3) of molarity. Such solution was subsequently dissolved in distilled water and followed by decantation and filtration processes to obtain the deposit. Eventually, the deposit was drained to form MS powders. The BET characterization showed that the respective surface areas of MS1, MS2, and MS3 are 0.350 m2/g, 2.869 m2/g, and 1.176 m2/g with the pore sizes of 30Å, 542 Å, and 550 Å, respectively. The XRF characterization results showed that the Al/Si ratio of MS10, MS15, and MS20 are 2.4, 2.2, and 2.3, respectively. Meanwhile, the XRD investigation pointed out that the primary phase of MS10 and MS15 samples wassodalite with cubic crystal system, quartz with hexagonal crystal system, and diaspore with orthorhombic crystal system, while the MS20 phase was pure in the form of sodalite phase. Moreover, the results of FITR characterization showed that the synthesized MS has a functional group of Si-O-Si bending, Si-O-Al, Si-O, Si-O normal to the plane stretching, inner surface Al-OH deformation, Si-O-Si siloxine, H-O-H, -OH, C-H stretching, and H-O-H bending water.

  7. Heats of formation and protonation thermochemistry of gaseous benzaldehyde, tropone and quinone methides

    Science.gov (United States)

    Bouchoux, Guy

    2010-08-01

    Quantum chemistry calculations using composite G3B3, G3MP2B3 and CBS-QB3 methods were performed for benzaldehyde, 1, tropone, 2, ortho-quinone methide, 3, para-quinone methide, 4, their protonated forms 1H+- 4H+ and the isomeric meta-hydroxybenzyl cation 5H+. The G3B3 298 K heats of formation values obtained in this work are: -39, 61, 52, 39, 661, 679, 699, 680 and 733 kJ mol -1 for 1- 4, 1H+- 5H+, respectively. At the same level of theory, computed proton affinities are equal to 834, 916, 887 and 892 kJ mol -1 for molecules 1- 4. These results allow to correct discrepancies on the previously reported thermochemistry of molecules 2- 4 and cations 2H+- 5H+.

  8. Heterocyclyl linked anilines and benzaldehydes as precursors for biologically significant new chemical entities

    Indian Academy of Sciences (India)

    Raman K Verma; Vijay Kumar; Prithwish Ghosh; Lalit K Wadhwa

    2012-09-01

    Benzylidene and benzyl thiazolidinediones, oxazolidinediones, isoxazolidinediones and their acyclic analogs like alpha alkylthio/alkoxy phenylpropanoic acids, beta-keto esters and tyrosine-based compounds possess broad therapeutic potential in general and as Peroxisome Proliferator Activated Receptors (PPARs) agonists in particular in the management of hyperglycemia and hyperlipidaemia for the treatment of Type 2 Diabetes (T2D). We have synthesised and characterized some novel and suitably substituted heterocyclyl linked benzaldehydes and anilines, which can be easily and very readily derivatized to all the above mentioned classes to generate new chemical entities of broader biological significance. Synthesis of their benzylidene thiazolidinedione and diethyl malonate and also benzyl diethyl malonate and alpha-bromoesters derivatives is reported in some of the cases in the present work.

  9. Study of the modification of coal-tar pitch with p-methyl benzaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Qilang Lin; Tiehu Li; Yongbin Ji; Wenzhi Wang; Xiaoxian Wang [Northwestern Polytechnical University, Xi' an (China). Department of Materials Science and Engineering

    2005-02-01

    Coal-tar pitch is modified with p-methyl benzaldehyde (PMB) in the presence of p-toluene sulfonic acid (PTS). The main characteristics of the modified pitches such as coking value, softening point and solubility are studied in this paper. The molecular structures of the modified pitches are studied using FT-IR and {sup 1}H-NMR spectroscopy techniques. In addition, the morphologies of the modified pitches are inspected with SEM, and the optical textures of resultant semi-cokes are characterized by polarized-light microscopy. Results show that the modified pitches have much higher coking value and {beta}-resins content than the parent pitch. There exist many microfibers with a uniform distribution in the modified pitches. Moreover, the modification results in an improvement in the optical textures of resultant semi-cokes. 28 refs., 6 figs., 1 tab.

  10. Synthesis of 1-methyl-2-phenyl-4-arylphthalazinium salts and their reaction with benzaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Ovchinnikova, I.G.; Pavlova, L.A.; Samartseva, I.V.

    1986-10-01

    1-Methyl-2-phenyl-4-arylphthalazinium perchorates, which exhibit the characteristics of CH acids, were obtained by the action of methylmagnesium iodide on 1-oxo-2-phenyl-4-aryl-1,2-dihydrophthalazines (Ar = C/sub 6/H/sub 5/, p-CH/sub 3/C/sub 6/H/sub 4/, p-C/sub 2/H/sub 5/OC/sub 6/H/sub 4/, p-FC/sub 6/H/sub 4/, p-ClC/sub 6/H/sub 4/, p-BrC/sub 6/H/sub 4/) followed by decomposition of the reaction mass with 57% perchloric acid. The 1-methylphthalazinium salts condense with benzaldehyde, giving 1-styryl-2-phenyl-4-arylphthalazinium perchlorates.

  11. Suppression of electroreductive dimerization of benzaldehyde by addition of. cap alpha. -cyclodextrin

    Energy Technology Data Exchange (ETDEWEB)

    Matsue, T.; Tasaki, C.; Fujihira, M.; Osa, T.

    1983-05-01

    Electrochemical reduction of carbonyl compounds to the corresponding alcohols is an important subject in organic electrochemistry. The effect of ..cap alpha..-cyclodextrin (..cap alpha..-CD) on the electroreduction of benzaldehyde was investigated. The reduction in aqueous system produces benzyl alcohol and 1,2-diphenyl-1,2-ethanediol (hydrobenzoin, dimerization product). The addition of ..cap alpha..-CD caused the decrease in the yield of hydrobenzoin. This suppression effect was observed both in the controlled potential and controlled current electrolyses. This is accounted for by the retardation of the dimerization rate between the neutral radicals, since inclusion of substrate provides severe steric hindrance around the reaction site. The addition had only a small influence on the stereochemistry of hydrobenzoin formed by the dimerization.

  12. Radiation chemical study on benzaldehyde-chlorobenzene system. A novel radiation chemical route for benzophenone formation

    Energy Technology Data Exchange (ETDEWEB)

    Sife-Eldeen, Kh.A. [National Center for Radiation Research and Technology, Nasr City, Cairo (Egypt)

    2009-07-01

    The effects of reactants molar ratio, absorbed dose, and absorbed dose rate were studied on benzaldehyde-chlorobenzene system. Irradiation products were identified by GC/MS analysis and their quantities were determined by GC analysis. Study of the reactants molar ratio effect indicates important aspects of the radiation chemistry of this system. It was observed that the yields of the major products increase as absorbed dose increase. On the other hand, these yields decrease as dose rate increases. Which reflects that the major products are formed via inter-spur reactions i.e. in the bulk of the medium. The mechanisms of the formation of the products were suggested. Benzophenone is one of the main products of this system. Therefore, this study gives a spot of light on a novel radiation chemical route for benzophenone formation. The radiation chemical yield (G-value) of benzophenone was determined at different dose rates. (orig.)

  13. Electronic excitation energies, three-state intersections, and photodissociation mechanisms of benzaldehyde and acetophenone

    Science.gov (United States)

    Cui, Ganglong; Lu, You; Thiel, Walter

    2012-06-01

    We report a theoretical study on the electronically excited states and the mechanisms of photodissociation of C6H5CHO and C6H5COCH3. For both molecules, we find an S1/T2/T1 three-state intersection region, which allows for an efficient S1 → T1 intersystem crossing via the T2 state that acts as a relay. Consequently, T1 reactions become the major radical photodissociation channels. According to the computed energy profiles, T1 photodissociation mainly yields phenyl and formyl radicals in the case of benzaldehyde, and benzoyl and methyl radicals in the case of acetophenone, with different C-C bonds being cleaved preferentially. The computational results agree well with the available experimental data.

  14. STUDY ON THE TREATMENT OF 3—PHENOXY—BENZALDEHYDE INDUSTRIAL WASTEWATER WITH POLYMERIC ADSORBENT

    Institute of Scientific and Technical Information of China (English)

    ZhuShiyun; ChenJinlong; 等

    1998-01-01

    In this paper,the two effluents from PBA (3-phenoxy-benzaldehyde) production process were treated by polymeric adsorbent CHA-111.PBA or PBC (3-phenoxy-benzoic acid) was recovered from the wastewater in the process of neutralization.As a secondary treatment method,adsorption with CHA-111 showed better efficiency than photocatolytic decomposition and solvent extraction.The optimal technological parameters were:adsorption:current velocity:2.0BV/hr(bed volume per hour),room temperature;desorption:current velocity:2.0BV/hr(bed volume per hour),room temperature;desorption:current velocity:1.0 BV/hr,80℃,8% sodium hydroxide aqueous solutions.In conclusion,99.9% COD in the neutralizing wastewater and 98.4% COD in the hydrolysis wastewater are removed successfully.

  15. The selective oxidation of toluene to benzaldehyde applying a fuel cell system in the gas phase

    Energy Technology Data Exchange (ETDEWEB)

    Otsuka, K.; Ishizuka, K.; Yamanaka, I.; Hatano, M. (Dept. of Chemical Engineering, Tokyo Inst. of Technology, Ookayama, Meguro-ku, Tokyo 152 (JP))

    1991-11-01

    This paper discusses a fuel cell system used for the synthesis of benzaldehyde from toluene in the gas phase. The cell system (anode: Pd-black with added graphite/H{sub 3}PO{sub 4}(aq.)/cathode: Pt-black with added graphite) operated at ca. 373 K under short-circuit conditions and produced the partial oxidation products benzaldehyde (PhCHO) and benzoic acid (PhCOOH). The addition of chlorides such as HCl, NaCl, MgCl{sub 2}, etc., to the anode remarkably improved the selectivity of the sum of PhCHO and PhCOOH. In the presence of chlorides, CO{sub 2} was not produced at all. Among the chlorides tested, NaCl is the best additive for the synthesis of PhCHO. Kinetic results on the reaction with the NaCl-added anode have shown that decreasing temperatures and increasing pressures of the reactants (toluene and O{sub 2}) favor the oxidation to PhCHO. The oxidation of toluene under an externally applied potential showed a product distribution similar to that observed under short-circuit conditions. The turnover number grater than unite (2.4) indicates catalytic cycling of the Pd in the anode. The current efficiency was improved by cyclic short- and open-circuit operation of the cell. A reaction mechanism assuming a {pi} allylbenzyl-Pd{sup 2+} (ligand){sub x} complex as the reaction intermediate explains the kinetic results and the favorable effect of chloride. The intermediate complex may be generated through the electrochemical oxidation of Pd and toluene. The subsequent competitive formations of PhCHO and CO{sub 2} from this complex proceed nonelectrochemically.

  16. Raman Spectroscopy and Electrochemical Investigations of Pt Electrocatalyst Supported on Carbon Prepared through Plasma Pyrolysis of Natural Gas

    Directory of Open Access Journals (Sweden)

    Tereza Cristina Santos Evangelista

    2015-01-01

    Full Text Available Physicochemical and electrochemical characterisations of Pt-based electrocatalysts supported on carbon (Vulcan carbon, C1, and carbon produced by plasma pyrolysis of natural gas, C2 toward ethanol electrooxidation were investigated. The Pt20/C180 and Pt20/C280 electrocatalysts were prepared by thermal decomposition of polymeric precursors at 350°C. The electrochemical and physicochemical characterisations of the electrocatalysts were performed by means of X-ray diffraction (XRD, transmission electron microscope (TEM, Raman scattering, cyclic voltammetry, and chronoamperometry tests. The XRD results show that the Pt-based electrocatalysts present platinum metallic which is face-centered cubic structure. The results indicate that the Pt20/C180 electrocatalyst has a smaller particle size (10.1–6.9 nm compared with the Pt20/C280 electrocatalyst; however, the Pt20/C280 particle sizes are similar (12.8–10.4 nm and almost independent of the reflection planes, which suggests that the Pt crystallites grow with a radial shape. Raman results reveal that both Vulcan carbon and plasma carbon are graphite-like materials consisting mostly of sp2 carbon. Cyclic voltammetry and chronoamperometry data obtained in this study indicate that the deposition of Pt on plasma carbon increases its electrocatalytic activity toward ethanol oxidation reaction.

  17. Preparation And Characterization Of Modified Calcium Oxide From Natural Sources And Their Application In The Transesterification Of Palm Oil

    Directory of Open Access Journals (Sweden)

    Aqliliriana

    2015-08-01

    Full Text Available Abstract Calcium oxide catalysts were prepared from natural calcium sources such as limestone and mud creeper shell and the catalytic activities were evaluated in the transesterification of palm oil. The raw material which mainly composed of calcium carbonate can be easily converted to calcium oxide CaO after calcination above 1000 K for few hours. Abundant cheap sources benign high conversion and nontoxic become main advantages of these catalysts. The catalysts were characterized by XRF TGA XRD CO2-TPD SEM and BET methods. Thermal decomposition of CaCO3 will produced CaO which later will be converted into calcium hydroxide CaOH2 via simple hydration technique. Under optimum reaction condition methanol to oil ratio 151 catalyst loading 3 wt. reaction temperature 338 K for 5 hours the highest conversion of palm oil to methyl ester recorded were 98 and 94 when using modified limestone and mud creeper shell respectively. The results observed an increment up to 80 by using modified catalysts with characterization results showed high in basicity and surface area. Hence promising materials via simple and cheap method can be achieved.

  18. Simple grinding-induced reactions of 2-aminobenzyl alcohol and benzaldehyde derivatives, a rapid synthetic route to 3,1-benzoxazines

    Directory of Open Access Journals (Sweden)

    I. B. Masesane

    2014-05-01

    Full Text Available The grinding-induced reactions of 2-aminobenzyl alcohol and benzaldehyde derivatives in the presence of 30 mol% of acetic acid to give 3,1-benzoxazines are described. The reactions were performed at room temperature affording 3,1-benzoxazines in yields above 95% and high purity when benzaldehyde and its chloro and nitro derivatives were used. DOI: http://dx.doi.org/10.4314/bcse.v28i2.14

  19. The Production of Benzaldehyde by Rhizopus oligosporus USM R1 in a Solid State Fermentation (SSF System of Soy Bean Meal: Rice Husks

    Directory of Open Access Journals (Sweden)

    Norliza, A. W.

    2005-01-01

    Full Text Available The cultivation of Rhizopus oligosporus USM R1 for the production of benzaldehyde, a bitter cherry almond flavour was performed using soya bean meal and rice husks as the substrates. The identification of R. oligosporus USM R1 was performed based on the observation made under light microscope and scanning electron microscope (SEM. The optimum conditions for the SSF in a 250-ml Erlenmeyer flask system were 40% (v/w water content, substrate particle size of 0.7 mm; inoculum size of 1 x 10^5 spores/g substrate; incubation temperature of 30C; substrate amount of 7 g and the ratio of soy bean meal: rice husks of 50:50%. A maximum benzaldehyde production was obtained when the substrate was agitated after 48 hour for a 96 hour fermentation time. The highest benzaldehyde production obtained after 96 hour cultivation was 5.47 mg g-1 substrate. The supplementation of carbon and nitrogen sources in the substrate mixture revealed an enhancement in the growth and benzyldehyde production. A maximum production of benzaldehyde was obtained with the supplementation of L-phenylalanine, a precursor for benzaldehyde biosynthesis which gave 38.69 mg benzaldehyde/g substrate. This is approximately 6-folds higher compared to the substrates without the supplementation of L-phenylalanine.

  20. Real-Time Detection of Traces of Benzaldehyde in Benzyl Alcohol as a Solvent by a Flexible Lanthanide Microporous Metal-Organic Framework.

    Science.gov (United States)

    Zhang, Huan; Chen, Diming; Ma, Huili; Cheng, Peng

    2015-10-26

    Luminescent 3D lanthanide metal-organic framework (Ln-MOF) {[Tb2 (TATAB)2 ]⋅4 H2 O⋅6 DMF}n (1) was synthesized under solvothermal conditions by using flexible ligand 4,4',4''-s-triazine-1,3,5-triyltri-p-aminobenzoate (TATAB). A phase transition was observed between low temperature and room temperature. The luminescence of 1 could be enhanced by formaldehyde and quenched efficiently by trace amounts of benzaldehyde in solvents such as benzyl alcohol (0.01-2.0 vol %) and ethanol (0.01-2.5 vol %). This is the first use of a Ln-MOF as chemical sensor for both formaldehyde and benzaldehyde. The high sensitivity and selectivity of the luminescence response of 1 to benzaldehyde allows it to be used as an excellent sensor for identifying benzaldehyde and provides a simple and convenient method for detecting traces of benzaldehyde in benzyl alcohol based injections. This work establishes a new strategy for detection of benzaldehyde in benzyl alcohol by luminescent MOFs.

  1. SYNTHESIS OF SOME CINNAMIC ACID DERIVATIVES: EFFECT OF GROUPS ATTACHED ON AROMATIC RING TO THE REACTIVITY OF BENZALDEHYDE

    Directory of Open Access Journals (Sweden)

    Marcellino Rudyanto

    2010-06-01

    Full Text Available Synthesis of cinnamic acid and its six derivatives has been done by employing Knoevenagel reaction. Benzaldehyde, 4-butylbenzaldehyde, 4-t-butylbenzaldehyde, 4-butoxybenzaldehyde, 4-phenylbenzaldehyde, 5-bromo-2,4-dimethoxybenzaldehyde, and 5-bromo-2,3-dimethoxybenzaldehyde were reacted with malonic acid in pyridine – piperidine to give cinnamic acid (85,3%, 4-butylcinnamic acid (69,3%, 4-t-butylcinnamic acid (77,7%, 4-butoxycinnamic acid (64,5%, 4-phenylcinnamic acid (65,5%, 5-bromo-2,4-dimethoxycinnamic acid (53,2% and 5-bromo-2,4-dimethoxycinnamic acid (57,2%, respectively. It was disclosed that 4-alkyl, 4-alkoxy, 4-aryl, dan 2-alkoxy groups decrease the reactivity of carbonyl carbon of benzaldehyde.   Keywords: cinnamic acid, cinnamic acid derivatives, Knoevenagel reaction

  2. Gas phase proton affinities of molecules in excited electronic states by ion cyclotron resonance spectroscopy. [Benzaldehyde, cyanobenzene, and pyridine

    Energy Technology Data Exchange (ETDEWEB)

    Freiser, B.S.; Beauchamp, J.L.

    1976-01-07

    Ion cyclotron resonance spectroscopy is proposed as a method to determine acid-base properties of molecules in excited electronic states. Proton affinity in the excited state can be determined from the proton affinity in the ground state plus the difference in excitation energies of the base and its conjugate acid. The difference in excitation energies may be determined by analyzing the absorption spectra of the base and the photodissociation spectra of its conjugate acid. Gas phase absorption spectra of benzaldehyde, cyanobenzene and pyradine and their respective conjugate acids were presented and discussed. The greatest increase of proton affinity was reported in the excitation state of benzaldehyde with lesser increases reported for the excitation states of cyanobenzene and pyridine. (DDA)

  3. Polydopamine-Coated TiO2 Nanotubes for Selective Photocatalytic Oxidation of Benzyl Alcohol to Benzaldehyde Under Visible Light.

    Science.gov (United States)

    Tripathy, Jyotsna; Loget, Gabriel; Altomare, Marco; Schmuki, Patrik

    2016-05-01

    TiO2 nanotube arrays grown by anodization were coated with thin layers of polydopamine as visible light sensitizer. The PDA-coated TiO2 scaffolds were used as photocatalyst for selective oxidation of benzyl alcohol under monochromatic irradiation at 473 nm. Benzaldehyde was selectively formed and no by-products could be detected. A maximized reaction yield was obtained in O2-saturated acetonitrile. A mechanism is proposed that implies firstly the charge carrier generation in polydopamine as a consequence of visible light absorption. Secondly, photo-promoted electrons are injected in TiO2 conduction band, and subsequently transferred to dissolved O2 to form O*2- radicals. These radicals react with benzyl alcohol and lead to its selective dehydrogenation oxidation towards benzaldehyde.

  4. Studies on crystal growth and physical properties of 4-(dimethylamino)benzaldehyde-2,4-dinitroaniline single crystal

    Science.gov (United States)

    Jebin, R. P.; Suthan, T.; Rajesh, N. P.; Vinitha, G.; Dhas, S. A. Britto

    2016-07-01

    The organic material 4-(dimethylamino)benzaldehyde-2,4-dinitroaniline has been grown by slow evaporation technique. Single crystal and Powder X-ray diffraction studies have been carried out to conform the grown crystal. FTIR and FT-Raman spectra were recorded to identify the functional groups present in the crystal. The optical property of the grown crystal was analysed by UV-Vis-NIR measurement. The thermal property of the grown crystal was analysed by thermogravimetric (TG) and differential thermal analyses (DTA). Thermal diffusivity of the grown crystal was analysed by Photo acoustic spectroscopic (PAS) studies. The third order nonlinear optical properties of 4-(dimethylamino)benzaldehyde-2,4-dinitroaniline was measured by the Z-scan technique using 532 nm diode pumped continuous wave (CW) Nd:YAG laser. The mechanical property of the grown crystal was analysed by using microhardness studies.

  5. Influence of substituted benzaldehydes and their derivatives as inhibitors for hydrogen evolution in lead/acid batteries

    Energy Technology Data Exchange (ETDEWEB)

    Dietz, H. [Technische Univ. Dresden, Inst. fuer Physikalische Chemie und Elektrochemie (Germany); Hoogestraat, G. [DETA-Akkumulatorenwerk GmbH, Bad Lauterberg (Germany); Laibach, S. [Kurt-Schwabe-Inst. fuer Mess- und Sensortechnik e.V., Meinsberg (Germany); Borstel, D. von [DETA-Akkumulatorenwerk GmbH, Bad Lauterberg (Germany); Wiesener, K. [Kurt-Schwabe-Inst. fuer Mess- und Sensortechnik e.V., Meinsberg (Germany)

    1995-02-01

    The influence of substituted benzaldehydes and their derivatives (e.g. vanillin) as inhibitors for hydrogen evolution on smooth and porous negative electrodes of the lead/acid system is investigated by cyclic voltammetric measurements. The experiments have been carried out with and without the presence of antimony. The effect of the inhibitors can be distinguished by a moderate and a strong inhibiting action. Use of these inhibitors in flooded lead/acid batteries can reduce water loss during cycling by 50%. (orig.)

  6. In situ growth of carbon nanotubes on Ni/MgO: a facile preparation of efficient catalysts for the production of synthetic natural gas from syngas.

    Science.gov (United States)

    Fan, M T; Lin, J D; Zhang, H B; Liao, D W

    2015-11-07

    Ni/MgO-CNTs catalysts are prepared by in situ chemical vapor deposition growth of CNTs on Ni/MgO. These catalysts exhibit an improved performance for the production of synthetic natural gas from syngas, which is attributed to the formation of highly catalytic active interfaces among Ni, CNTs and MgO.

  7. Inhibitory Kinetics of p-Substituted Benzaldehydes on Polyphenol Oxidase from the Fifth Instar of Pieris Rapae L.

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Polyphenol oxidase (PPO) is the enzyme responsible for enzymatic browning during the growth of insects. It is also involved in defense reactions and is related with immunities in insects. PPO,a metalloenzyme oxidase, catalyzes the oxidation of o-diphenol to o-quinone. The present paper describes the effects of benzaldehyde and its p-substituted derivatives on the activity of PPO from the fifth instar of Pieris rapae L. PPO from the fifth instar of Pieris rapae L. was purified using ammonium sulfate fractionation and chromatography on Sephadex G-100. The enzyme kinetics was characterized using L-3,4-dihydroxyphenylalanine (L-DOPA) as substrate. The results show that benzaldehyde, p-hydroxybenzaldehyde, p-chlorobenzaldehyde, and p-cyanobenzaldehyde can inhibit the PPO activity for the oxidation of L-DOPA. The inhibitor concentration leading to 50% activity lost, IC50, was estimated to be 5.90, 5.62, 2.83, and 2.91 mmol/L for the four tested inhibitors, respectively. Kinetic analyses show that the inhibitory effects of these compounds are reversible. Benzaldehyde, p-hydroxybenzaldehyde, and p-chlorobenzaldehyde are noncompetitive inhibitors while p-cyanobenzaldehyde is a mixed-type inhibitor. The inhibition constants were determined for all four inhibitors.p-chlorobenzaldehyde and p-cyanobenzaldehyde were more potent inhibitors than the other compounds. These results provide a basis for developing PPO inhibition-based pesticides.

  8. Structure of the ThDP-dependent enzyme benzaldehyde lyase refined to 1.65 Å resolution

    Energy Technology Data Exchange (ETDEWEB)

    Maraite, Andy; Schmidt, Thomas; Ansörge-Schumacher, Marion B. [Department of Biotechnology, Faculty of Natural Sciences, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Brzozowski, A. Marek; Grogan, Gideon, E-mail: grogan@ysbl.york.ac.uk [Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5YW (United Kingdom); Department of Biotechnology, Faculty of Natural Sciences, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany)

    2007-07-01

    The X-ray crystal structure of the ThDP-dependent enzyme benzaldehyde lyase has been refined to 1.65 Å. Benzaldehyde lyase (BAL; EC 4.1.2.38) is a thiamine diphosphate (ThDP) dependent enzyme that catalyses the enantioselective carboligation of two molecules of benzaldehyde to form (R)-benzoin. BAL has hence aroused interest for its potential in the industrial synthesis of optically active benzoins and derivatives. The structure of BAL was previously solved to a resolution of 2.6 Å using MAD experiments on a selenomethionine derivative [Mosbacher et al. (2005 ▶), FEBS J.272, 6067–6076]. In this communication of parallel studies, BAL was crystallized in an alternative space group (P2{sub 1}2{sub 1}2{sub 1}) and its structure refined to a resolution of 1.65 Å, allowing detailed observation of the water structure, active-site interactions with ThDP and also the electron density for the co-solvent 2-methyl-2,4-pentanediol (MPD) at hydrophobic patches of the enzyme surface.

  9. Quantification of brown dog tick repellents, 2-hexanone and benzaldehyde, and release from tick-resistant beagles, Canis lupus familiaris.

    Science.gov (United States)

    de Oliveira Filho, Jaires Gomes; Sarria, André Lucio Franceschini; Ferreira, Lorena Lopes; Caulfield, John C; Powers, Stephen J; Pickett, John A; de León, Adalberto A Pérez; Birkett, Michael A; Borges, Lígia Miranda Ferreira

    2016-06-01

    We have recently shown that repellency of the tick Rhipicephalus sanguineus sensu lato by the tick resistant dog breed, the beagle, is mediated by volatile organic compounds (VOCs) 2-hexanone and benzaldehyde present in beagle odour. Ectoparasite location of animal hosts is affected by variation in these odour components and their ratios. The aim of this study was to quantify the release rate, and the ratio, of 2-hexanone and benzaldehyde from beagles. The odour of three beagles was collected, for four days, over one week (day 0, day 1, day 4 and day 7). The compounds were identified using coupled high-resolution gas chromatography-mass spectrometry (GC-MS), and authentic standards of compounds were used to generate external calibration curves for quantification. Both compounds were found in all dogs on all days. The amount of benzaldehyde was always higher than that of 2-hexanone and so their ratio varied from unity, on average (over time) being 3.128±0.365, 1.902±0.390, 1.670±0.671ngmL(-1) for beagle 1, 2 and 3, respectively. There was no significant (pbenzaldehyde in beagle odour samples covering a 7-day period. This knowledge enables development of repellents to protect dogs from R. sanguineus s. l. infestation.

  10. Structure of vanadium oxide on supports as measure by the benzaldehyde-ammonia titration method

    Energy Technology Data Exchange (ETDEWEB)

    Niwa, M.; Matsuoka, Y.; Murakami, Y.

    1987-08-13

    In order to clarify the structure of vanadium oxide on supports, the benzaldehyde-ammonia titration (BAT) method was applied to various supported vanadium oxide catalysts. Prior to the measurements, an infrared study of the adsorbed benzoate ion on TiO/sub 2/, ZrO/sub 2/, and CeO/sub 2/ was carried out to justify the BAT method to measure surface cus sites. The exposed surface area of the supports Al/sub 2/O/sub 3/, TiO/sub 2/, and ZrO/sub 2/ with different crystal phases was then measured, and the surface area of vanadium oxide supported was calculated by the difference between BET and exposed surfaced areas. On the other hand, the surface area of vanadium oxide on SiO/sub 2/ was measured after reduction on 773 K, because benzaldehyde was adsorbed on the reduced V/sub 2/O/sub 3/ but not on SiO/sub 2/. Based on these measurements, the relationship between percent coverage on support and surface V/sub 2/O/sub 5/ concentration was obtained. The structure of supported V/sub 2/O/sub 5/ thus determined depended on the kind of support, but not significantly on the crystal phase. Except in small concentration on Al/sub 2/O/sub 3/ and SiO/sub 2/, vanadium oxide formed a multilayer. The support surface at Al/sub 2/O/sub 3/(..gamma..) was covered most effectively, and the average thickness of V/sub 2/O/sub 5/ in 100% of the coverage was 3 layers. To the contrary, the SiO/sub 2/ surface was not covered effectively, and the average thickness attained up to 50 layers. Furthermore, ZrO/sub 2/ and TiO/sub 2/ showed intermediate behavior between these supports. It is shown that the coverage efficiency and thickness of the formed metal oxides are correlated with the electronegativity of the cations of supports.

  11. Structure and Luminescence Property of a Hexanuclear Silver(Ⅰ) Cluster Containing Benzaldehyde Thiosemicarbazone

    Institute of Scientific and Technical Information of China (English)

    SUN Qiao-Zhen

    2011-01-01

    A new hexanuclear silver (I) compound 2 containing thiosemicarbazone with the group of benzene was synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analysis and fluorescence spectrum. The title compound crystallizes in triclinic, space group P with a = 11.611(3), b = 15.610(5), c = 15.624(7) , α = 113.942(6), β = 104.520(6), γ = 104.230(4)°, V = 2304.1(14) 3, C60H77Ag6N22O4.5S6, Mr = 2018.02, Dc = 1.454 g/cm3, μ(MoKα) = 1.435 mm-1, F(000) = 1005, Z = 1, the final R = 0.0468 and wR = 0.1474 for 6608 observed reflections (I 2σ(I)). In the structure, the S atom of the ligand L2 (L2 = benzaldehyde thiosemicarbazone) served as a triply bridged chelator to connect the six silver atoms into a Ag6L26 cluster. The luminescence property of compound 2 was investigated at room temperature.

  12. Benzaldehyde thiosemicarbazone derived from limonene complexed with copper induced mitochondrial dysfunction in Leishmania amazonensis.

    Directory of Open Access Journals (Sweden)

    Elizandra Aparecida Britta

    Full Text Available BACKGROUND: Leishmaniasis is a major health problem that affects more than 12 million people. Treatment presents several problems, including high toxicity and many adverse effects, leading to the discontinuation of treatment and emergence of resistant strains. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated the in vitro antileishmanial activity of benzaldehyde thiosemicarbazone derived from limonene complexed with copper, termed BenzCo, against Leishmania amazonensis. BenzCo inhibited the growth of the promastigote and axenic amastigote forms, with IC(50 concentrations of 3.8 and 9.5 µM, respectively, with 72 h of incubation. Intracellular amastigotes were inhibited by the compound, with an IC(50 of 10.7 µM. BenzCo altered the shape, size, and ultrastructure of the parasites. Mitochondrial membrane depolarization was observed in protozoa treated with BenzCo but caused no alterations in the plasma membrane. Additionally, BenzCo induced lipoperoxidation and the production of mitochondrial superoxide anion radicals in promastigotes and axenic amastigotes of Leishmania amazonensis. CONCLUSION/SIGNIFICANCE: Our studies indicated that the antileishmania activity of BenzCo might be associated with mitochondrial dysfunction and oxidative damage, leading to parasite death.

  13. Kinetics and catalysis in co-oxidation of benzaldehyde with alkylaromatic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, A.M. (Chernovisty State Univ. Ukr. S.S.R.); Chervinskii, K.A.; Mikhailovskaya, T.N.; Pluzhnikov, V.A.; Galabitskii, B.V.; Ivanova, L.A.; Pavlyuk, G.V.

    1978-01-01

    The presence of aldehydes increases the rates of liquid-phase oxidation of alkylaromatic hydrocarbons (AAH), e.g., cumene, ethylbenzene, p-xylene, or toluene, by molecular oxygen at 20/sup 0/-60/sup 0/C to values characteristic for oxidation of AAH alone at 100/sup 0/-120/sup 0/C. Kinetic studies showed that aldehydes cause rapid chain propagation via the formation of R radicals from RH and conversion of relatively unreactive RO/sub 2/ radicals to hydroperoxides. Due to self-inhibition by phenols formed in the chain oxidation of aromatic aldehydes, e.g., benzaldehyde, the process follows steady-state kinetics, which ensures a much larger induction factor for AAH co-oxidation with aromatic than with aliphatic aldehydes, which oxidize in a self-accelerating regime. Although salts of transition metals (mainly cobalt) favor the self-accelerating regime and thus reduce the induction factor, they catalyze oxidation of oxygen compounds present in the system by hydroperoxides (HPO), which, together with the induced HPO decomposition, are the main reactions preventing HPO accumulation.

  14. Continuous transformation of benzaldehyde to benzyl alcohol by Rhodotorula mucilaginosa immobilized in an ultrafiltration cell

    Energy Technology Data Exchange (ETDEWEB)

    Wisniewski, J.; Winnicki, T.; Majewska, K.

    1982-06-01

    Microbiological transformation of benzaldehyde accomplished by the fungus Rhodotorula mucilaginosa immobilized in the ultrafiltration cell was studied. A polysulfone membrane formed on a sintered PVC support was used for the separation of the transformation product from the cellular material. Kinetic investigations have led to results which are typical of continuously fed stirred tank reactors (CFSTR)-the value of the maximum reaction rate (Vmax) and apparent Michaelis constant (K'm) are practically independent of the substrate retention time (calculated in terms of the flow intensity value). A strong relationship was found to occur between Vmax and biomass concentration in the reactor. Study of the apparent enzyme stability shows that the decrease in the biocatalyst activity is chiefly caused by penetration of the cells through the membrane. The experimental results were approximated in terms of the adopted mathematical model. Based on this model, the half-lives (t1/2) of enzyme activities were determined. The t1/2 value varies from 35 to 82 days and depends both on the permeate flux through the membrane and on the separation properties of the membrane. (Refs. 15).

  15. Polyoxometalate coordinated transition metal complexes as catalysts: Oxidation of styrene to benzaldehyde/benzoic acid

    Indian Academy of Sciences (India)

    Srinivasa Rao Amanchi; Anjali Patel; Samar K Das

    2014-11-01

    Oxidation of styrene is carried out by using heptamolybdate coordinated transition metal (Co2+, Zn2+) complexes, [2-ampH]4[{Co(H2O)5}Mo7O24]·9H2O (1), [3-ampH]4[{Co(H2O)5}Mo7O24]·9H2O (2), [2-ampH]4[{Zn(H2O)5}Mo7O24]·4H2O (3) and [3-ampH]4[{Zn(3-ampy)(H2O)4}Mo7O24]·4H2O (4) as catalysts and H2O2 as an oxidant at 80°C. The leaching study has been carried out to check the quality of catalyst and it has been reused for three times with good percentage of conversion. For the first two catalysts (compounds 1 and 2), the major product obtained is benzaldehyde, and benzoic acid is the major product for next two catalysts (compounds 3 and 4). Stability of the catalysts has been analyzed by IR, UV-spectroscopy and powder X-ray crystallography.

  16. Silage preparation and fermentation quality of natural grasses treated with lactic acid bacteria and cellulase in meadow steppe and typical steppe.

    Science.gov (United States)

    Hou, Meiling; Ge, Gentu; Liu, Tingyu; Jia, Yushan; Cai, Yimin

    2016-09-27

    Silage preparation and fermentation quality of natural grasses in meadow steppe (MS) and typical steppe (TS) were studied. MS and TS contained thirty-three and nine species of natural grasses, respectively. Stipa Baicalensis in MS and Stipa grandi in TS were the dominant grasses with the highest dry matter (DM) yield. The crude protein (CP), neutral detergent fiber (NDF) and water-soluble carbohydrate (WSC) of the mixed natural grasses in both steppes were 8.02 to 9.03, 66.75 to 69.47 and 2.02 to 2.20% on a DM basis, respectively. The small-scale silages and round bale silages of mixed natural grasses in both steppes were prepared using the commercial lactic acid bacteria (LAB) inoculants Chikuso-1 (CH, Lactobacillus plantarum) and cellulase enzyme (AC, Acremonium cellulase) as additives. All silages treated with LAB and cellulase were well preserved with lower pH, butyric acid and ammonia-N content, and higher lactic acid and CP content than those of control in four kinds of silages. Compared with CH- or AC-treated silages, the CH+AC-treated silages had higher lactic acid content. The results confirmed that combination with LAB and cellulase may result in beneficial effects by improving the natural grass silage fermentation in both grasslands.

  17. Preparation of sol-gel TiO{sub 2}/purified Na-bentonite composites and their photovoltaic application for natural dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Saelim, Ni-on [Petroleum and Petrochemical College, Chulalongkorn University, Bangkok 10330 (Thailand); Polymer Processing and Polymer Nanomaterials Research Unit, Chulalongkorn University, Bangkok 10330 (Thailand); Magaraphan, Rathanawan, E-mail: rathanawan.k@chula.ac.th [Petroleum and Petrochemical College, Chulalongkorn University, Bangkok 10330 (Thailand); Polymer Processing and Polymer Nanomaterials Research Unit, Chulalongkorn University, Bangkok 10330 (Thailand); Center for Petroleum, Petrochemicals, and Advanced Materials, Chulalongkorn University, Bangkok 10330 (Thailand); Sreethawong, Thammanoon [Petroleum and Petrochemical College, Chulalongkorn University, Bangkok 10330 (Thailand); Center for Petroleum, Petrochemicals, and Advanced Materials, Chulalongkorn University, Bangkok 10330 (Thailand)

    2011-08-15

    Highlights: {yields} Natural dye from red cabbage was successfully employed in DSSC. {yields} A fast sol-gel method to produce TiO{sub 2}/clay thin film was proposed. {yields} The sol-gel-prepared TiO{sub 2}/clay was applied as the scattering layer on top of TiO{sub 2} electrode. {yields} Thicker sol-gel-prepared TiO{sub 2}/clay electrode showed higher DSSC efficiency. - Abstract: The sol-gel TiO{sub 2}/purified natural clay electrodes having Ti:Si molar ratios of 95:5 and 90:10 were initially prepared, sensitized with natural red cabbage dye, and compared to the sol-gel TiO{sub 2} electrode in terms of physicochemical characteristics and solar cell efficiency. The results showed that the increase in purified Na-bentonite content greatly increased the specific surface area and total pore volume of the prepared sol-gel TiO{sub 2}/purified Na-bentonite composites because the clay platelets prevented TiO{sub 2} particle agglomeration. The sol-gel TiO{sub 2}/5 mol% Si purified Na-bentonite and sol-gel TiO{sub 2}/10 mol% Si purified Na-bentonite composites could increase the film thickness of solar cells without cracking when they were coated as a scattering layer on the TiO{sub 2} semiconductor-based film, leading to increasing the efficiency of the natural dye-sensitized solar cells in this work.

  18. A Microbiological Preparation Based on the Homofermentative Strains of Lactobacillus plantarum Isolated from the Natural Sources for Bioconservation of Plant Resources (Review of Studies between 2000 and 2015

    Directory of Open Access Journals (Sweden)

    R.A. Shurkhno

    2016-03-01

    Full Text Available The paper reviews studies performed by the author for improving the process of bioconservation of plant resources by creating an effective microbiological preparation based on the active strains of lactic acid bacteria. It is known that the problem of production of biological preservatives can be solved by using the basic principles of microbiological and biotechnological processes that contribute to the creation of biological preservatives ensuring the most optimal and efficient fermentation of plant mass, i.e., by using homofermentative lactic acid bacteria (Lactobacillus plantarum isolated from the natural ecological niches, as well as by conservation of plant mass with the help of lactic acid bacteria at the stage of high physiological activity. In view of the above features, а microbial preparation “Universal Silage Ferment – BIOAGRO” was developed on the basis of two new strains of Lactobacillus plantarum RS3 and L. plantarum RS4, both isolated from natural sources, and implemented in the industrial production. Indus-trial introduction and testing of the microbiological preparation was carried out for 3 years (2012–2014 in ten farms of eight districts of the Republic of Tatarstan (Russia. It was found that the use of the preparation along with an optimized technology of bioconservation of high-protein perennials, annual grasses, their mixtures and corn, and slightly dried herbs in anaerobic conditions improves the qualitative characteristics of silage and haylage, as well as increases their energy value and enhances the economic performance of technological processes of fodder conservation.

  19. A Novel Porous Carrier Found in Nature for Nanocomposite Materials Preparation: A Case Study of Artemia Egg Shell-Supported TiO2 for Formaldehyde Removal

    Directory of Open Access Journals (Sweden)

    Sufeng Wang

    2015-01-01

    Full Text Available Artemia egg shells have an asymptotic sized pore structure (pore diameter: 500 nm–2500 nm, which could be used as a porous carrier for the preparation of nanocomposite materials. The objective of the present study was to prepare shell-supported TiO2 using a naturally porous carrier, Artemia egg shell, and to exhibit a case study of shell-supported TiO2 for formaldehyde removal. Characterization of shell-TiO2 using SEM-EDS, TEM, and XRD proved that Artemia shell with asymptotic reduction pores (pore diameter: 500 nm–2500 nm can be used as the carrier for nanocomposite materials. Artemia egg shell-supported TiO2 in polycrystalline-like nanostructures can be used for the high efficiency removal (adsorption and degradation of formaldehyde under visible light. Our results suggest that iron, one of the shell’s components, should broaden the absorption of visible light and enhance the photocatalytic efficiency of nanotitanium dioxide under visible light. Due to their interesting absorption and formaldehyde removal qualities, Artemia egg shell, as a novel naturally porous carrier for nanocomposite materials preparation, especially in the preparation of nanocatalysts, is worthy of further study.

  20. A case series of the effects of a novel composition of a traditional natural preparation for the treatment of psoriasis.

    Science.gov (United States)

    Michalsen, A; Eddin, O; Salama, A

    2016-10-01

    The objective of this study was to assess the effectiveness of a specific composition of a traditional herbal preparation (DurrDerma) in adult patients with moderate to severe skin psoriasis. The preparation is a newly developed topical combination containing plant-based extracts traditionally used in skin disease as black cumin, olive oil, tea tree oil, cocoa butter completed by vitamin A and vitamin B12. We documented the effectiveness of the preparation in a first case series. A total of 12 patients (8 males and 4 females, 21-86 y) with manifest and treatment-resistant psoriasis were included and treated for 12 weeks. All patients were assigned to twice-daily treatment with the DurrDerma preparation. Treatment success as determined by the Psoriasis Area and Severity Index (PASI) score, the body surface area, and the dermatology life index was achieved (PASI reduction of >75%) in 10 of the 12 treated patients (83%). The remaining two patients showed a PASI reduction of ≤50%. In 5 of the patients PASI reduction was achieved <12 weeks (between week 3-11). The beneficial effect in responder patients might be explained by a synergistic anti-oxidative and anti inflammatory activity of all components present in DurrDerma. We conclude that the new preparation using a traditional approach seems to be a promising complementary treatment for psoriasis.

  1. A case series of the effects of a novel composition of a traditional natural preparation for the treatment of psoriasis

    Directory of Open Access Journals (Sweden)

    A. Michalsen

    2016-10-01

    Full Text Available The objective of this study was to assess the effectiveness of a specific composition of a traditional herbal preparation (DurrDerma in adult patients with moderate to severe skin psoriasis. The preparation is a newly developed topical combination containing plant-based extracts traditionally used in skin disease as black cumin, olive oil, tea tree oil, cocoa butter completed by vitamin A and vitamin B12. We documented the effectiveness of the preparation in a first case series. A total of 12 patients (8 males and 4 females, 21–86 y with manifest and treatment-resistant psoriasis were included and treated for 12 weeks. All patients were assigned to twice-daily treatment with the DurrDerma preparation. Treatment success as determined by the Psoriasis Area and Severity Index (PASI score, the body surface area, and the dermatology life index was achieved (PASI reduction of >75% in 10 of the 12 treated patients (83%. The remaining two patients showed a PASI reduction of ≤50%. In 5 of the patients PASI reduction was achieved <12 weeks (between week 3–11. The beneficial effect in responder patients might be explained by a synergistic anti-oxidative and anti inflammatory activity of all components present in DurrDerma. We conclude that the new preparation using a traditional approach seems to be a promising complementary treatment for psoriasis.

  2. Effects of natural childbirth preparation versus standard antenatal education on epidural rates, experience of childbirth and parental stress in mothers and fathers: a randomised controlled multicentre trial

    Science.gov (United States)

    Bergström, M; Kieler, H; Waldenström, U

    2009-01-01

    Objective To examine the effects of antenatal education focussing on natural childbirth preparation with psychoprophylactic training versus standard antenatal education on the use of epidural analgesia, experience of childbirth and parental stress in first-time mothers and fathers. Design Randomised controlled multicentre trial. Setting Fifteen antenatal clinics in Sweden between January 2006 and May 2007. Sample A total of 1087 nulliparous women and 1064 of their partners. Methods Natural group: Antenatal education focussing on natural childbirth preparation with training in breathing and relaxation techniques (psychoprophylaxis). Standard care group: Standard antenatal education focussing on both childbirth and parenthood, without psychoprophylactic training. Both groups: Four 2-hour sessions in groups of 12 participants during third trimester of pregnancy and one follow-up after delivery. Main outcome measures Epidural analgesia during labour, experience of childbirth as measured by the Wijma Delivery Experience Questionnaire (B), and parental stress measured by the Swedish Parenthood Stress Questionnaire. Results The epidural rate was 52% in both groups. There were no statistically significant differences in the experience of childbirth or parental stress between the randomised groups, either in women or men. Seventy percent of the women in the Natural group reported having used psychoprophylaxis during labour. A minority in the Standard care group (37%) had also used this method, but subgroup analysis where these women were excluded did not change the principal findings. Conclusion Natural childbirth preparation including training in breathing and relaxation did not decrease the use of epidural analgesia during labour, nor did it improve the birth experience or affect parental stress in early parenthood in nulliparous women and men, compared with a standard form of antenatal education. PMID:19538406

  3. 78 FR 38024 - Magnolia LNG, LLC; Liquefied Natural Gas Limited; Notice of Intent To Prepare an Environmental...

    Science.gov (United States)

    2013-06-25

    ... Energy Regulatory Commission Magnolia LNG, LLC; Liquefied Natural Gas Limited; Notice of Intent To...) that will discuss the environmental impacts of the Magnolia Liquefied Natural Gas Project (Magnolia LNG Project) involving construction and operation of facilities by Magnolia LNG, LLC (Magnolia) in...

  4. The Ministry of Land and Natural Resources is Preparing to Delete the Approval Right for Mineral Resources Geological Prospecting

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>Yu Haifeng, Deputy Director of Geological Prospecting Department and Executive Deputy Director of the Mineral Prospecting Office under the Ministry of Land and Natural Resources, disclosed at the recently concluded National Prospecting Meeting for 2013 that, the Ministry of Land and Natural Resources is con

  5. A nanoporous 3D zinc(II) metal–organic framework for selective absorption of benzaldehyde and formaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Moradpour, Tahereh [School of Chemistry, College of Science, University of Tehran, Tehran (Iran, Islamic Republic of); Abbasi, Alireza, E-mail: aabbassi@khayam.ut.ac.ir [School of Chemistry, College of Science, University of Tehran, Tehran (Iran, Islamic Republic of); Van Hecke, Kristof [XStruct, Department of Inorganic and Physical Chemistry, Ghent University, Krigslaan 281-S3, Ghent B-9000 (Belgium)

    2015-08-15

    A new 3D nanoporous metal–organic framework (MOF), [[Zn{sub 4}O(C{sub 24}H{sub 15}N{sub 6}O{sub 6}){sub 2}(H{sub 2}O){sub 2}]·6H{sub 2}O·DMF]{sub n} (1) based on 4,4′,4″-s-triazine-1,3,5-triyltri-p-aminobenzoate (TATAB) ligand was solvothermally synthesized and characterized by single–crystal X-ray diffraction, Powder X-ray diffraction (PXRD), infrared spectroscopy (IR) and Brunauer–Emmett–Teller (BET) analyses. X-ray single crystal diffraction analysis reveals that 1 exhibits a 3D network with new kvh1 topology. Semi-empirical (AM1) calculations were carried out to obtain stable conformers for TATAB ligand. In addition, the absorption of two typical aldehydes (benzaldehyde and formaldehyde) in the presence of 1 was investigated and the effect of the aldehyde concentration, exposure time and temperature was studied. It was found that compound 1 has a potential for the absorption of aldehydes under mild conditions. - Graphical abstract: Absorption of two typical aldehydes (formaldehyde and benzaldehyde) by solvothermally synthesized of a 3D nano-porous MOF based on TATAB tricarboxylate ligand and Zn (NO{sub 3}){sub 2}·6H{sub 2}O. - Highlights: • We present a 3D Zn(II)-MOF with TATAB linker by solvothermal method. • The framework possesses a new kvh1 topology. • The framework displays formaldehyde and benzaldehyde absorption property. • Conformational analysis was performed to determine the stable linker geometry.

  6. Isolation of liver aldehyde oxidase containing fractions from different animals and determination of kinetic parameters for benzaldehyde

    Directory of Open Access Journals (Sweden)

    Kadam R

    2008-01-01

    Full Text Available Aldehyde oxidase activity containing fractions from rabbit, guinea pig, rat and mouse livers were obtained by heat treatment and ammonium sulfate precipitation. Aldehyde oxidase activity was observed in rabbit and guinea pig livers, while aldehyde oxidase activity was absent in rat and mouse liver fractions. Enzyme kinetic parameters, K m and V max , were determined for the oxidation of benzaldehyde to benzoic acid by rabbit and guinea pig liver fractions, by spectrophotometric method, with potassium ferricyanide as the electron acceptor. The K m values obtained for both animal liver fractions were in the range of 10.3-19.1 µM.

  7. Synthesis of diverse dihydropyrimidine-related scaffolds by fluorous benzaldehyde-based Biginelli reaction and post-condensation modifications

    Directory of Open Access Journals (Sweden)

    Bruno Piqani

    2011-09-01

    Full Text Available Dihydropyrimidinones and dihydropyrimidinethiones generated from the Biginelli reactions of perfluorooctanesulfonyl-attached benzaldehydes are used as common intermediates for post-condensation modifications such as cycloaddition, Liebeskind–Srogl reaction and Suzuki coupling to form biaryl-substituted dihydropyrimidinone, dihydropyrimidine, and thiazolopyrimidine compounds. The high efficiency of the diversity-oriented synthesis is achieved by conducting a multicomponent reaction for improved atom economy, under microwave heating for fast reaction, and with fluorous solid-phase extractions (F-SPE for ease of purification.

  8. Correlation analysis of the /sup 13/C NMR spectra of some para-substituted benzaldehyde oximes and their anions

    Energy Technology Data Exchange (ETDEWEB)

    Rutkovskii, G.V.; Zmeikov, V.P.

    1987-06-20

    For the case of the /sup 13/C NMR spectra of a series of para-substituted benzaldehyde oximes and their anions it was shown that to describe the chemical shifts of all the carbon atoms of the benzene ring and the exocyclic CH group it is necessary to use three-parameter equations with the parameters F and R (which characterize the inductive and resonance effects respectively of the substituents), and Q (which corresponds to the paramagnetic interaction between the substituents and the carbon atoms).

  9. Spectroelectrochemical investigations of the reduction of benzaldehyde and p-cyano- and p-phenylbenzaldehyde in sulfolane

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, N.R. (Sandia Labs., Albuquerque, NM); Quinn, R.K.; Vanderborgh, N.E.

    1977-04-07

    Spectroelectrochemical investigations are presented for the reduction of benzaldehyde and p-cyano- and p-phenylbenzaldehyde in the solvent sulfolane. Two reduction intermediates were observed for the p-cyanobenzaldehyde reduction. One intermediate was the radical anion which was consumed in a dimerization reaction, k/sub 2/ = 85--88 M/sup -1/ s/sup -1/. The other intermediate was the electrochemically inactive complex between the radical anion and the unreduced parent. The verification of this complexation clarifies previous voltammetric studies of this type of reduction mechanism.

  10. Determination of {sup 19} F - {sup 13} C coupling constants and their use in mono fluoro benzaldehyde derivatives conformational analysis

    Energy Technology Data Exchange (ETDEWEB)

    Villar, Jose Daniel Figueroa [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Inst. de Quimica

    1995-12-31

    The element fluorine is extremely important in medicinal chemistry. In order to research the possible molecular alterations introduced for the substitution of hydrogen for fluorine, the study of {sup 19} F-{sup 13} C coupling constants is necessary. In this work, ortho- and para-fluorine-substituted benzaldehydes and some other aromatic fluoro compounds were studied using {sup 1} H, {sup 13} C and {sup 19} F NMR. The long range C-F coupling constants were measured from the PND spectra and compared with the long range values of H-C coupling constants, so as to, at first, determine their importance in conformational analysis 5 refs., 2 figs., 3 tabs.

  11. β-cyclodextrin functionalized on glass micro-particles: A green catalyst for selective oxidation of toluene to benzaldehyde

    Science.gov (United States)

    Tahir, M. Nazir; Nielsen, Thorbjørn T.; Larsen, Kim L.

    2016-12-01

    Oxidation of toluene is considered an important process which often requires high temperatures and specific conditions along with heavy-metals based catalysts. In this study, we have developed a green catalyst by functionalizing beta-cyclodextrin onto glass micro-particle surfaces. All surfaces were characterized by X-ray photoelectron spectroscopy and applied to catalyze the selective oxidation of toluene into benzaldehyde (82% yield) at room temperature. The catalyst was stable and could be used repeatedly for several cycles without losing efficiency.

  12. 4-{Phenyl[4-(6-phenyl-2,2′-bipyridin-4-ylphenyl]amino}benzaldehyde

    Directory of Open Access Journals (Sweden)

    Yu-yang Zhang

    2014-08-01

    Full Text Available The title molecule, C35H25N3O, is a triphenylamine derivative with the 4-position substituted by an aldehyde group, and the 4′-position substituted by a 6-phenyl-2,2′-bipyridine group. The whole molecule is non-planar and the dihedral angle between the core benzene and pyridine rings is 36.96 (5°. The dihedral angle between the phenyl and benzaldehyde groups bonded to the amine N atom is 70.86 (5°.

  13. Toluene oxidization to benzaldehyde in subcritical water%近临界水中甲苯氧化生成苯甲醛

    Institute of Scientific and Technical Information of China (English)

    朱宪; 王倩

    2006-01-01

    Effects of reaction parameter on yield of benzaldehyde produced from toluene oxidization using hydrogen peroxide in subcriti cal water are investigated. The experimental results show that if the molar ratio of hydrogen peroxide to toluene is controlled within a reasonable range, the by-products may be neglected. The optimum technology of toluene oxidization to benzaldehyde is reaction time 60 min,reaction temperature 350 ℃, molar ratio of hydrogen peroxide to toluene 3.5. The yield of benzaldehyde can reach 17.2% under the optimum condition. Research results of chemical reaction kinetics show that the consecutive reaction consists of two first-order reaction, and activation energy of these two reactions are 89 kJ· mol-1 and 76 kJ· mol-1 respectively.

  14. Rapid and sensitive determination of benzaldehyde arising from benzyl alcohol used as preservative in an injectable formulation solution using dispersive liquid-liquid microextraction followed by gas chromatography.

    Science.gov (United States)

    Mashayekhi, Hossein Ali; Rezaee, Mohammad; Garmaroudi, Shirin Sadeghi; Montazeri, Naser; Ahmadi, Seyed Javad

    2011-01-01

    A rapid and sensitive method has been developed for the determination of benzaldehyde, a toxic oxidation product of the widely used preservative and co-solvent benzyl alcohol in injectable formulations of non-steroidal anti-inflammatory drugs, diclofenac, vitamin B-complex and Voltaren injection solutions by using dispersive liquid-liquid microextraction followed by gas chromatography. This method involves the use of an appropriate mixture of extraction solvent (43.0 µL 1,2-dichloroethane) and disperser solvent (1.0 mL acetonitrile) for the formation of a cloudy solution in a 5.0-mL aqueous sample containing benzaldehyde. The linear range was 1.0-1000 µg L(-1), and the limit of detection was 0.2 µg L(-1) for benzaldehyde.

  15. Is Naval Hospital Bremerton as Prepared as They Should be to Respond to a Man-Made or Natural Disaster

    Science.gov (United States)

    2006-12-18

    Stakeholder Analysis -------------------------- 48 Competitor Analysis --------------------------- 50 Internal Analysis ---------------------------------- 59 2...Bremerton Preparedness Stakeholder Analysis -------------------------- 65 SWOT Analysis --------------------------------- 65 Checklists and...and how does this influence how they respond and need to be prepared. Next there will be a competitor analysis . A competitor analysis looks at the

  16. The Double Bind for Women: Exploring the Gendered Nature of Turnaround Leadership in a Principal Preparation Program

    Science.gov (United States)

    Weiner, Jennie Miles; Burton, Laura J.

    2016-01-01

    In this study of nine participants in a turnaround principal preparation program, Jennie Miles Weiner and Laura J. Burton explore how gender role identity shaped participants' views of effective principal leadership and their place within it. The authors find that although female and male participants initially framed effective leadership…

  17. Stability studies of cosmetic emulsions prepared from natural products such as wine, grape seed oil and mastic resin

    NARCIS (Netherlands)

    Glampedaki, P.; Dutschk, V.

    2014-01-01

    An attempt was made in this study to use diluted wine as the aqueous phase and grapeseed oil as the oil phase for the preparation of oil-in-water cosmetic emulsions. Two monovarietal wines of Hellenic origin were used in this study; a red one from Sangiovese grapes and a white one from Muscat of Sam

  18. Electrical Wiring of the Aldehyde Oxidoreductase PaoABC with a Polymer Containing Osmium Redox Centers: Biosensors for Benzaldehyde and GABA

    Directory of Open Access Journals (Sweden)

    Artavazd Badalyan

    2014-11-01

    Full Text Available Biosensors for the detection of benzaldehyde and g-aminobutyric acid (GABA are reported using aldehyde oxidoreductase PaoABC from Escherichia coli immobilized in a polymer containing bound low potential osmium redox complexes. The electrically connected enzyme already electrooxidizes benzaldehyde at potentials below −0.15 V (vs. Ag|AgCl, 1 M KCl. The pH-dependence of benzaldehyde oxidation can be strongly influenced by the ionic strength. The effect is similar with the soluble osmium redox complex and therefore indicates a clear electrostatic effect on the bioelectrocatalytic efficiency of PaoABC in the osmium containing redox polymer. At lower ionic strength, the pH-optimum is high and can be switched to low pH-values at high ionic strength. This offers biosensing at high and low pH-values. A “reagentless” biosensor has been formed with enzyme wired onto a screen-printed electrode in a flow cell device. The response time to addition of benzaldehyde is 30 s, and the measuring range is between 10–150 µM and the detection limit of 5 µM (signal to noise ratio 3:1 of benzaldehyde. The relative standard deviation in a series (n = 13 for 200 µM benzaldehyde is 1.9%. For the biosensor, a response to succinic semialdehyde was also identified. Based on this response and the ability to work at high pH a biosensor for GABA is proposed by coimmobilizing GABA-aminotransferase (GABA-T and PaoABC in the osmium containing redox polymer.

  19. 氨基磺酸催化合成苯甲醛乙二醇缩醛%Synthesis of Benzaldehyde Ethylene Glycol Acetal with Aminosulfonic Acid as Catalyst

    Institute of Scientific and Technical Information of China (English)

    王俏; 张玉琦; 魏清勃

    2013-01-01

    The benzaldehyde ethylene glycol acetal was synthesized from benzaldehyde and ethylene glycol in the presence of aminosulfonic acid which was used as catalyst.The effects of molar ratio of benzaldehyde to ethylene glycol,reaction time,amount of catalyst and water carrying agent,etc.on the yield of benzaldehyde ethylene glycol acetal were investigated.The best reaction conditions were found as follows:n(benzaldehyde):n (ethylene glycol)=1:1.5,the mass ratio of aminosulfonic acid was 1.5% of total reactants,the water carrying agent was 16mL (2.18% of total reactants) and the reaction time was 1.5h.Under these conditions,the yield of benzaldehyde ethylene glycol acetal could reach 83.73%.%以氨基磺酸为催化剂合成了苯甲醛乙二醇缩醛,考察了醛醇摩尔比,反应时间,催化剂用量,带水剂用量等因素对苯甲醛乙二醇缩醛收率的影响.结果表明:最适宜的工艺条件是:n(苯甲醛):n(乙二醇)=1:1.5,催化剂用量占反应物总质量的1.5%,带水剂环己烷用量为16mL(占反应物总质量的2.18%),反应时间1.5h,上述条件下,苯甲醛乙二醇缩醛收率可达到83.73%.

  20. Electrical Wiring of the Aldehyde Oxidoreductase PaoABC with a Polymer Containing Osmium Redox Centers: Biosensors for Benzaldehyde and GABA.

    Science.gov (United States)

    Badalyan, Artavazd; Dierich, Marlen; Stiba, Konstanze; Schwuchow, Viola; Leimkühler, Silke; Wollenberger, Ulla

    2014-12-01

    Biosensors for the detection of benzaldehyde and γ-aminobutyric acid (GABA) are reported using aldehyde oxidoreductase PaoABC from Escherichia coli immobilized in a polymer containing bound low potential osmium redox complexes. The electrically connected enzyme already electrooxidizes benzaldehyde at potentials below -0.15 V (vs. Ag|AgCl, 1 M KCl). The pH-dependence of benzaldehyde oxidation can be strongly influenced by the ionic strength. The effect is similar with the soluble osmium redox complex and therefore indicates a clear electrostatic effect on the bioelectrocatalytic efficiency of PaoABC in the osmium containing redox polymer. At lower ionic strength, the pH-optimum is high and can be switched to low pH-values at high ionic strength. This offers biosensing at high and low pH-values. A "reagentless" biosensor has been formed with enzyme wired onto a screen-printed electrode in a flow cell device. The response time to addition of benzaldehyde is 30 s, and the measuring range is between 10-150 µM and the detection limit of 5 µM (signal to noise ratio 3:1) of benzaldehyde. The relative standard deviation in a series (n = 13) for 200 µM benzaldehyde is 1.9%. For the biosensor, a response to succinic semialdehyde was also identified. Based on this response and the ability to work at high pH a biosensor for GABA is proposed by coimmobilizing GABA-aminotransferase (GABA-T) and PaoABC in the osmium containing redox polymer.

  1. Polymer characterization and optimization of conditions for the enhanced bioproduction of benzaldehyde by Pichia pastoris in a two-phase partitioning bioreactor.

    Science.gov (United States)

    Craig, Tom; Daugulis, Andrew J

    2013-04-01

    Benzaldehyde, with its apricot and almond-like aroma, is the second most abundantly used molecule in the flavor industry, and is most commonly produced via chemical routes, such as by the oxidation of toluene. Biologically produced benzaldehyde, whether by extraction of plant material or via microbial biotransformation, commands a substantial price advantage, and greater consumer acceptance. Methylotrophic yeast, such as Pichia pastoris, contain the enzyme alcohol oxidase (AOX), which, in the presence of alcohols other than methanol, are able to yield aldehydes as dead-end products, for example, benzaldehyde from benzyl alcohol. In this work, we have determined that benzaldehyde, and not benzyl alcohol, is inhibitory to the transformation reaction by P. pastoris, prompting the development of a selection strategy for identifying sequestering polymers for use in a partitioning bioreactor that was based on the ratio of partition coefficients (PCs) for the two target molecules. Additionally, we have now confirmed for the first time, that the mechanism of solute uptake by amorphous polymers is via absorption, not adsorption. Finally, we have adopted a common strategy used for the production of heterologous proteins by P. pastoris, namely the use of a mixed methanol/glycerol feed for inducing the required AOX enzyme, while reducing the time required for high density biomass generation. All of these components were combined in a final experiment in which 10% of the polymer Kraton D1102K, whose PC ratio of benzaldehyde to benzyl alcohol was 14.9, was used to detoxify the biotransformation in a 5 L partitioning bioreactor, resulting in a 3.4-fold increase in benzaldehyde produced (14.4 g vs. 4.2 g) relative to single phase operation, at more than double the volumetric productivity (97 mg L(-1) h(-1) vs. 41 mg L(-1) h(-1) ).

  2. A New Iterative Approach for the Synthesis of Oligo(phenyleneethynediyl) Derivatives and Its Application for the Preparation of Fullerene-Oligo(phenyleneethynediyl) Conjugates as Active Photovoltaic Materials

    NARCIS (Netherlands)

    Nierengarten, Jean-François; Gu, Tao; Hadziioannou, Georges; Tsamouras, Dimitris; Krasnikov, Victor

    2004-01-01

    Disymmetrically substituted oligo(phenyleneethynediyl) (OPE) derivatives were prepared from 2,5-bis(octyloxy)-4-[(triisopropylsilyl)ethynyl]benzaldehyde (5) by an iterative approach using the following reaction sequence: i) Corey-Fuchs dibromoolefination, ii) treatment with an excess of lithium diis

  3. 2-Phenyl-tetrahydropyrimidine-4(1H-ones – cyclic benzaldehyde aminals as precursors for functionalised β2-amino acids

    Directory of Open Access Journals (Sweden)

    Markus Nahrwold

    2009-09-01

    Full Text Available Novel procedures have been developed to condense benzaldehyde effectively with β-amino acid amides to cyclic benzyl aminals. Double carbamate protection of the heterocycle resulted in fully protected chiral β-alanine derivatives. These serve as universal precursors for the asymmetric synthesis of functionalised β2-amino acids containing acid-labile protected side chains. Diastereoselective alkylation of the tetrahydropyrimidinone is followed by a chemoselective two step degradation of the heterocycle to release the free β2-amino acid. In the course of this study, an L-asparagine derivative was condensed with benzaldehyde and subsequently converted to orthogonally protected (R-β2-homoaspartate.

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

    Directory of Open Access Journals (Sweden)

    Paricha Pongjirawat

    2014-09-01

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

  5. Co-ETS-10 and Co-AM-6 as active catalysts for the oxidation of styrene to styrene oxide and benzaldehyde using molecular oxygen

    Institute of Scientific and Technical Information of China (English)

    Shuvo Jit Datta; Kyung Byung Yoon

    2015-01-01

    Pristine ETS-10 and AM-6 and their Co2+-exchanged forms were prepared, and their catalytic activi-ties toward the oxidation of styrene in oxygen atmosphere were studied in dimethylformamide. The catalysts were denoted as Co-E10-n (n=0, 9, 26, 68, 81) and Co-A6-m (m=0, 8, 23, 63, 79), where n and m denote the degree of Co2+exchange. The products of the oxidation process were identified as styrene epoxide (E) and benzaldehyde (B). Both the pristine forms, ETS-10 (Co-E10-0) and AM-6 (Co-A6-0), and Co2+-exchanged forms displayed catalytic activities. With increasing n or m, the con-version, and hence the rate, increased. Specifically, the rates varied from 6.1 to 12.5 mmol·g−1·h−1 with increasing n (Co-E10-n catalysts) and from 5.4 to 12.4 mmol·g−1·h−1 with increasing m (Co-A6-m catalysts). In contrast, the E/B ratio decreased with increasing n or m. More specifically, the E/B ratio decreased from 2.1 to 0.1 with increasing n from 0 to 81 (Co-E10-n catalysts) and from 1.3 to 0.1 with increasing m from 0 to 79 (Co-A6-m catalysts). Co-E10-9 displayed the highest E yield and Co-A6-79 generated the highest B yield. The highest turnover frequency obtained was 36.3 Co−1·h−1, which was the highest one obtained among those obtained for the Co2+-exchanged zeolites and mesoporous silica reference materials studied in this work.

  6. Inclusion complexes of red bell pepper pigments with β-cyclodextrin: preparation, characterisation and application as natural colorant in yogurt.

    Science.gov (United States)

    Gomes, Lidiane Martins Mendes; Petito, Nicolly; Costa, Valéria Gonçalves; Falcão, Deborah Quintanilha; de Lima Araújo, Kátia G

    2014-04-01

    This work aimed to prepare inclusion complexes between red bell pepper pigments and β-cyclodextrin using two different procedures (i.e., magnetic stirring and ultrasonic homogenisation), to characterise the prepared inclusion complexes and to evaluate the colour stability of a selected complex added to yogurt. The mass ratio of extract to β-cyclodextrin was 1:4. The formed extract: β-cyclodextrin complexes and a physical mixture of extract and β-cyclodextrin were evaluated by differential scanning calorimetry, Fourier transform-infrared spectroscopy, proton nuclear magnetic resonance, particle size distribution and Zeta potential. The obtained data showed that ultrasonic homogenisation resulted in better yield and inclusion efficiency compared to magnetic stirring. The yogurt with the added complex produced by ultrasonic homogenisation showed slower variations for the a(∗) (redness) and b(∗) (yellowness) indices compared to yogurt with added extract, indicating a higher protection of the colour during storage.

  7. Fe(III)-photocatalytic partial oxidation of benzyl alcohol to benzaldehyde under UV-solar simulated radiation.

    Science.gov (United States)

    Spasiano, Danilo; Marotta, Raffaele; Di Somma, Ilaria; Andreozzi, Roberto; Caprio, Vincenzo

    2013-11-01

    A great deal of interest is recorded among researchers in the identification of new catalytic systems that make possible the selective oxidation of organic species in the presence of non-toxic solvents, primarily water, through the use of inexpensive catalysts. The possibility to selectively oxidize benzyl alcohol to benzaldehyde is studied in the present work by using ferric ions as homogeneous catalysts and oxygen as an oxidant under UV-solar simulated radiation. Due to the possibility that Fe(III) aquo-complex photolysis could generate undesired reactive OH radicals with the consequent occurrence of side reactions, most of the runs are carried out at pH = 0.5 at which these events have a reduced incidence. The results indicate that benzyl alcohol can be partially converted into benzaldehyde with yield and selectivity values higher than 40% and 80% respectively for the conditions adopted, with a minor occurrence of benzoic acid formation. Reaction schemes to account for the experimental observations are provided.

  8. Kinetic. cap alpha. secondary deuterium isotope effects for O-ethyl S-phenyl benzaldehyde acetal hydrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Ferraz, J.P.; Cordes, E.H.

    1979-03-14

    The rate of hydrolysis of O-ethyl S-phenyl benzaldehyde acetal at 25/sup 0/C in 20% dioxane--80% water is independent of pH over the range pH6-12; k/sub obsd/ = 1.9 x 10/sup -7/s/sup -1/. Under more acidic conditions, the rate increases linearly with the activity of the hydrated proton; k/sub 2/ = 2.95 x 10/sup -2/M/sup -1/s/sup -1/. The kinetic ..cap alpha.. secondary deuterium isotope effect for acid-catalyzed hydrolysis of O-ethyl S-phenyl benzaldehyde acetal, measured at 25/sup 0/C in 20% aqueous dioxane containing 0.05 M HCl, is k/sub H//k/sub D/ = 1.038 +- 0.008, a value consistent with a transition state in which the C--S bond is stretched rather little. In contrast, the corresponding isotope effect for the pH-independent hydrolysis of this substrate, measured at 42.5/sup 0/C in 20% dioxane, is 1.13 +- 0.02, a value consistent with complete C--S bond cleavage in the transition state and rate-determining diffusion apart of the ion-pair formed as the initial intermediate, in accord with the suggestion of Jensen and Jencks. 1 figure, 4 tables.

  9. Vibrational, NMR and UV-visible spectroscopic investigation and NLO studies on benzaldehyde thiosemicarbazone using computational calculations

    Science.gov (United States)

    Moorthy, N.; Prabakar, P. C. Jobe; Ramalingam, S.; Pandian, G. V.; Anbusrinivasan, P.

    2016-04-01

    In order to investigate the vibrational, electronic and NLO characteristics of the compound; benzaldehyde thiosemicarbazone (BTSC), the XRD, FT-IR, FT-Raman, NMR and UV-visible spectra were recorded and were analysed with the calculated spectra by using HF and B3LYP methods with 6-311++G(d,p) basis set. The XRD results revealed that the stabilized molecular systems were confined in orthorhombic unit cell system. The cause for the change of chemical and physical properties behind the compound has been discussed makes use of Mulliken charge levels and NBO in detail. The shift of molecular vibrational pattern by the fusing of ligand; thiosemicarbazone group with benzaldehyde has been keenly observed. The occurrence of in phase and out of phase molecular interaction over the frontier molecular orbitals was determined to evaluate the degeneracy of the electronic energy levels. The thermodynamical studies of the temperature region 100-1000 K to detect the thermal stabilization of the crystal phase of the compound were investigated. The NLO properties were evaluated by the determination of the polarizability and hyperpolarizability of the compound in crystal phase. The physical stabilization of the geometry of the compound has been explained by geometry deformation analysis.

  10. Biosynthesis and characterization of silver nanoparticles prepared from two novel natural precursors by facile thermal decomposition methods

    Science.gov (United States)

    Goudarzi, Mojgan; Mir, Noshin; Mousavi-Kamazani, Mehdi; Bagheri, Samira; Salavati-Niasari, Masoud

    2016-09-01

    In this work, two natural sources, including pomegranate peel extract and cochineal dye were employed for the synthesis of silver nanoparticles. The natural silver complex from pomegranate peel extract resulted in nano-sized structures through solution-phase method, but this method was not efficient for cochineal dye-silver precursor and the as-formed products were highly agglomerated. Therefore, an alternative facile solid-state approach was investigated as for both natural precursors and the results showed successful production of well-dispersed nanoparticles with narrow size distribution for cochineal dye-silver precursor. The products were characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy dispersive X-ray microanalysis (EDX), and Transmission Electron Microscopy (TEM).

  11. Preparation and wear behavior of polymer matrix composites with an interpenetrating network structure derived from natural sponge

    Energy Technology Data Exchange (ETDEWEB)

    Wang Tianchi; Zhou Tianle; Xiong Dangsheng, E-mail: tianchiwang@yahoo.com.c [Department of Material Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China)

    2010-03-15

    Natural sponge was used as a template to produce carbon/epoxy resin and (carbon+silicon carbide)/epoxy resin composites with interpenetrating network structures. Carbon with a network structure was first obtained by pyrolysis of the natural sponge. The composites were then obtained by injecting epoxy resin and silicone resin into the carbon. Their microstructures and wear properties were analyzed. The results show that the natural structure of sponge controlled the interpenetrating network structures of the composites. The netlike carbon in the composites reduced the wear rate of the epoxy resin. Compared with the carbon/epoxy resin composite, the (carbon+silicon carbide)/epoxy resin composite shows better wear resistance.

  12. Preparation and validation of radio iodinated recombinant human IL-10 for the measurement of natural human antibodies against IL-10

    DEFF Research Database (Denmark)

    de Lemos Rieper, Carina; Galle, Pia; Svenson, Morten

    2009-01-01

    activity of 75 cpm/pg. Validation of the tracer confirmed preserved antibody epitopes and receptor binding ability. A robust Radio Immuno Assay (RIA) was developed and validated to detect natural human anti-IL-10 antibodies based on the formation of (125)I-labeled IL-10-IgG complexes in solution...

  13. 78 FR 49743 - Eastern Shore Natural Gas Company; Notice of Intent To Prepare an Environmental Assessment for...

    Science.gov (United States)

    2013-08-15

    ... involving construction and operation of facilities by Eastern Shore Natural Gas Company (Eastern Shore) in... whether the project is in the public convenience and necessity. This notice announces the opening of the... construct, operate, and maintain the proposed facilities. The company would seek to negotiate a...

  14. 77 FR 47052 - El Paso Natural Gas Company; Notice of Intent To Prepare an Environmental Impact Statement for...

    Science.gov (United States)

    2012-08-07

    ... (Project) involving construction and operation of facilities by El Paso Natural Gas Company (El Paso) in... whether the Project is in the public convenience and necessity. This notice announces the opening of the... maintain the planned facilities. The company would seek to negotiate a mutually acceptable...

  15. 77 FR 29629 - El Paso Natural Gas Company; Notice of Intent To Prepare an Environmental Assessment for the...

    Science.gov (United States)

    2012-05-18

    ... facilities by El Paso Natural Gas Company (EPNG) in El Paso County, Texas. The Commission will use this EA in its decision-making process to determine whether the project is in the public convenience and... about the acquisition of an easement to construct, operate, and maintain the proposed facilities....

  16. Thiol and Disulfide Derivatives of Ephedra Alkaloids 2 : A Mechanistic Study of Their Effect on the Addition of Diethyl Zinc to Benzaldehyde

    NARCIS (Netherlands)

    Fitzpatrick, Kevin; Hulst, Ron; Kellogg, Richard M.

    1995-01-01

    Thiol and disulfide derivatives of ephedrine have been shown previously to catalyse in high enantiomeric excess (ee) the reaction of diethyl zinc with benzaldehyde. We find that this reaction involves non-linear correlations between the ee of product and catalyst. Osmotic measurements indicate a hig

  17. Enhanced sensitivity of self-assembled-monolayer-based SPR immunosensor for detection of benzaldehyde using a single-step multi-sandwich immunoassay.

    Science.gov (United States)

    Gobi, K Vengatajalabathy; Matsumoto, Kiyoshi; Toko, Kiyoshi; Ikezaki, Hidekazu; Miura, Norio

    2007-04-01

    This paper describes the fabrication and sensing characteristics of a self-assembled monolayer (SAM)-based surface plasmon resonance (SPR) immunosensor for detection of benzaldehyde (BZ). The functional sensing surface was fabricated by the immobilization of a benzaldehyde-ovalbumin conjugate (BZ-OVA) on Au-thiolate SAMs containing carboxyl end groups. Covalent binding of BZ-OVA on SAM was found to be dependent on the composition of the base SAM, and it is improved very much with the use of a mixed monolayer strategy. Based on SPR angle measurements, the functional sensor surface is established as a compact monolayer of BZ-OVA bound on the mixed SAM. The BZ-OVA-bound sensor surface undergoes immunoaffinity binding with anti-benzaldehyde antibody (BZ-Ab) selectively. An indirect inhibition immunoassay principle has been applied, in which analyte benzaldehyde solution was incubated with an optimal concentration of BZ-Ab for 5 min and injected over the sensor chip. Analyte benzaldehyde undergoes immunoreaction with BZ-Ab and makes it inactive for binding to BZ-OVA on the sensor chip. As a result, the SPR angle response decreases with an increase in the concentration of benzaldehyde. The fabricated immunosensor demonstrates a low detection limit (LDL) of 50 ppt (pg mL(-1)) with a response time of 5 min. Antibodies bound to the sensor chip during an immunoassay could be detached by a brief exposure to acidic pepsin. With this surface regeneration, reusability of the same sensor chip for as many as 30 determination cycles has been established. Sensitivity has been enhanced further with the application of an additional single-step multi-sandwich immunoassay step, in which the BZ-Ab bound to the sensor chip was treated with a mixture of biotin-labeled secondary antibody, streptavidin and biotin-bovine serum albumin (Bio-BSA) conjugate. With this approach, the SPR sensor signal increased by ca. 12 times and the low detection limit improved to 5 ppt with a total response

  18. Recovery and Growth Potential of Listeria monocytogenes in Temperature Abused Milkshakes Prepared from Naturally Contaminated Ice Cream Linked to a Listeriosis Outbreak.

    Science.gov (United States)

    Chen, Yi; Allard, Emma; Wooten, Anna; Hur, Minji; Sheth, Ishani; Laasri, Anna; Hammack, Thomas S; Macarisin, Dumitru

    2016-01-01

    The recovery and growth potential of Listeria monocytogenes was evaluated in three flavors of milkshakes (vanilla, strawberry, and chocolate) that were prepared from naturally contaminated ice cream linked to a listeriosis outbreak in the U.S. in 2015, and were subsequently held at room temperature for 14 h. The average lag phase duration of L. monocytogenes was 9.05 h; the average generation time was 1.67 h; and the average population level increase per sample at 14 h was 1.14 log CFU/g. Milkshake flavors did not significantly affect these parameters. The average lag phase duration of L. monocytogenes in milkshakes with initial contamination levels ≤ 3 CFU/g (9.50 h) was significantly longer (P 3 CFU/g (8.60 h). The results highlight the value of using samples that are contaminated with very low levels of L. monocytogenes for recovery and growth evaluations. The behavior of L. monocytogenes populations in milkshakes prepared from naturally contaminated ice cream linked to the listeriosis outbreak should be taken into account when performing risk based analysis using this outbreak as a case study.

  19. Recovery and growth potential of Listeria monocytogenes in temperature abused milkshakes prepared from naturally contaminated ice cream linked to a listeriosis outbreak

    Directory of Open Access Journals (Sweden)

    Yi eChen

    2016-05-01

    Full Text Available The recovery and growth potential of Listeria monocytogenes was evaluated in three flavors of milkshakes (vanilla, strawberry, and chocolate that were prepared from naturally contaminated ice cream linked to a listeriosis outbreak in the U.S. in 2015, and were subsequently held at room temperature for 14 hours. The average lag phase duration of L. monocytogenes was 9.05 h; the average generation time was 1.67 h; and the average level increase per sample at 14 h was 1.15 log CFU/g. Milkshake flavors did not significantly affect these parameters. The average lag phase duration of L. monocytogenes in milkshakes with initial contamination levels ≤ 3 CFU/g (9.50 h was significantly longer (P 3 CFU/g (8.60 h. The results highlight the value of using samples that are contaminated with very low levels of L. monocytogenes for recovery and growth evaluations. The behavior of L. monocytogenes populations in milkshakes prepared from naturally contaminated ice cream linked to the listeriosis outbreak should be taken into account when performing risk based analysis using this outbreak as a case-study.

  20. Benzaldehyde Schiff bases regulation to the metabolism, hemolysis, and virulence genes expression in vitro and their structure-microbicidal activity relationship.

    Science.gov (United States)

    Xia, Lei; Xia, Yu-Fen; Huang, Li-Rong; Xiao, Xiao; Lou, Hua-Yong; Liu, Tang-Jingjun; Pan, Wei-Dong; Luo, Heng

    2015-06-05

    There is an urgent need to develop new antibacterial agents because of multidrug resistance by bacteria and fungi. Schiff bases (aldehyde or ketone-like compounds) exhibit intense antibacterial characteristics, and are therefore, promising candidates as antibacterial agents. To investigate the mechanism of action of newly designed benzaldehyde Schiff bases, a series of high-yielding benzaldehyde Schiff bases were synthesized, and their structures were determined by NMR and MS spectra data. The structure-microbicidal activity relationship of derivatives was investigated, and the antibacterial mechanisms were investigated by gene assays for the expression of functional genes in vitro using Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. The active compounds were selective for certain active groups. The polar substitution of the R2 group of the amino acids in the Schiff bases, affected the antibacterial activity against E. coli and S. aureus; specific active group at the R3 or R4 groups of the acylhydrazone Schiff bases could improve their inhibitory activity against these three tested organisms. The antibacterial mechanism of the active benzaldehyde Schiff bases appeared to regulate the expression of metabolism-associated genes in E. coli, hemolysis-associated genes in B. subtilis, and key virulence genes in S. aureus. Some benzaldehyde Schiff bases were bactericidal to all the three strains and appeared to regulate gene expression associated with metabolism, hemolysis, and virulence, in vitro. The newly designed benzaldehyde Schiff bases possessed unique antibacterial activity and might be potentially useful for prophylactic or therapeutic intervention of bacterial infections.

  1. Preparation and evaluation of the cytotoxic nature of TiO2 nanoparticles by direct contact method

    Directory of Open Access Journals (Sweden)

    Chellappa M

    2015-10-01

    Full Text Available M Chellappa,1 U Anjaneyulu,1 Geetha Manivasagam,2 U Vijayalakshmi1 1School of Advanced Sciences, Materials Chemistry Division, 2Centre for Biomaterials Science and Technology, School of Mechanical and Building Sciences, VIT University, Vellore, Tamil Nadu, India Abstract: The purpose of this study is to prepare and evaluate the effect of synthesized titanium dioxide (TiO2 nanoparticles for their biocompatibility on physiological body fluids and the effect of cell toxicity to produce osteointegration when used as implantable materials. For the past few decades, the number of researches done to understand the importance of the biocompatibility of bioceramics, metals, and polymers and their effect on clinical settings of biomedical devices has increased. Hence, the total concept of biocompatibility encourages researchers to actively engage in the investigation of the most compatible materials in living systems by analyzing them using suitable physical, chemical, and biological (bioassay methods. The ceramic material nano TiO2 was prepared by sol-gel method and analyzed for its functional group and phase formation by Fourier transform infrared spectroscopy and powder X-ray diffraction. Furthermore, the particle size, shape, surface topography, and morphological behavior were analyzed by dynamic light scattering, zeta potential, scanning electron microscopy–energy dispersive X-ray analysis, and transmission electron microscopy analysis. In addition to this, the cytotoxicity and cytocompatibility were determined on MG63 cell lines with varying doses of concentrations such as 1 µg/mL, 10 µg/mL, 25 µg/mL, 50 µg/mL, and 100 µg/mL with different time periods such as 24 hours and 48 hours. The results have not shown any toxicity, whereas, it improved the cell viability/proliferation at various concentrations. Hence, these findings indicate that the nano TiO2 material acts as a good implantable material when used in the biomedical field as a

  2. A resource for those preparing for and responding to natural disasters, humanitarian crises, and major healthcare emergencies.

    Science.gov (United States)

    Allen, Claire

    2014-12-01

    This article describes the dissemination and knowledge transfer activities of Evidence Aid, which was established after the Indian Ocean tsunami of December 2004 to provide a single source of evidence that would help people make well-informed decisions when preparing for and responding to disasters. Evidence Aid has a dedicated website (www.EvidenceAid.org) to provide access to more than 160 systematic reviews and several other documents relevant to people working on disaster risk reduction, planning, response, recovery, rehabilitation, and resilience. It combines this with a social media presence and Special Collections that bundle together related Cochrane Reviews (www.TheCochraneLibrary.com). The aim is to make it easier for users who need this evidence and don't have time to browse through multiple documents and distill them before making their decisions. Evidence Aid will continue to identify and share resources and knowledge with those who most need it at the time that they need it most. It is working with several partners to identify relevant Cochrane and non-Cochrane systematic reviews and is engaging with users who, by sharing their information and their knowledge needs, will allow Evidence Aid to target its efforts to these priority areas.

  3. Electrospinning process: Versatile preparation method for biodegradable and natural polymers and biocomposite systems applied in tissue engineering and drug delivery

    Science.gov (United States)

    Rogina, Anamarija

    2014-03-01

    Over the past two decades, the electrospinning process has shown a great potential in various applications, such as membrane filtration, catalytic processes, fibrous-sensor applications, drug delivery and tissue engineering, due to ability of facile producing high surface-to-volume fibrous structure. The most appealing electrospinning characteristic has shown to be the mimicking nano-scale fibrous topography of extracellular matrix (ECM) in tissue engineering field. The wide range of electrospinnable synthetic biodegradable and natural polymers offers fabrication of fibrous nano-structures with specific biological responses and mechanical properties. Conducting different processing parameters (needle geometry, tip-to-collector distance, electric field strength, collector composition and geometry) allows the altering of fiber size, density, alignment and overall morphology. So far, electrospinning process has shown limitless application in tissue engineering and drug delivery. The following review has been focused on studies of electrospinning process as the most promising fabrication technique for tissue engineering and drug delivery applications.

  4. Preparation and application of nanocrystalline cellulose derived from sugarcane waste as filler modified alkanolamide on crosslink of natural rubber latex film

    Science.gov (United States)

    Harahap, Hamidah; Hayat, Nuim; Lubis, Marfuah

    2017-07-01

    Sugarcane waste is abundant sources of cellulose and it has potential to reutilize. Cellulose from sugarcane waste can be derived into nanocystalline cellulose (NCC) from crystalline region. The NCC as a filler has capability to reinforce natural rubber latex product. The crosslink in vulcanized natural rubber latex film influences several properties of product. In this work, we extracted NCC from sugarcane waste then added into natural rubber latex as filler modified alkanolamide (ALK) and also studied the crosslink of natural rubber latex films. NCC were produced from sugarcane waste by hydrolysis process with sulfuric acid 45%. The obtained NCC was characterized by using x-ray diffraction (XRD), transmission electron microscopy (TEM), and fourier transform infra red (FTIR). NCC was modified by alkanolamide and dispersed in water with filler concentration of 10%. Then the dispersion were added into latex system followed by pre-vulcanization at 70 °C. The films were prepared by coagulant dipping method and dried at 100 °C and 120 °C for 20 minutes. Characterization of NCC from sugarcane waste by using FTIR was done, it clearly showed the functional groups of cellulose. TEM showed the obtained NCC were rod-shaped with about 40-160 nm in diameter and several hundred nm in length, and XRD showed that the degree of crystalinity of NCC from sugarcane waste is 92.33%. The crosslink of natural rubber films were studied by measure the crosslink density for different filler loading by using swelling measurement with toluene solution. The result show that the crosslink density increased in line with amount of filler which added into the system, and also the crosslink density that obtained from vulcanization at 120 °C were higher than 100 °C.

  5. From natural products to polymeric derivatives of "eugenol": a new approach for preparation of dental composites and orthopedic bone cements.

    Science.gov (United States)

    Rojo, Luis; Vazquez, Blanca; Parra, Juan; López Bravo, Antonio; Deb, Sanjukta; San Roman, Julio

    2006-10-01

    Polymers with eugenol moieties covalently bonded to the macromolecular chains were synthesized for potential application in orthopedic and dental cements. First, eugenol was functionalized with polymerizable groups. The synthetic methods employed afforded two different methacrylic derivatives, where the acrylic and eugenol moieties were either directly bonded, eugenyl methacrylate (EgMA), or separated through an oxyethylene group, ethoxyeugenyl methacrylate (EEgMA). A typical Fisher esterification reaction was used for the synthesis of EgMA and EEgMA, affording the desired monomers in 80% yields. Polymerization of each of the novel monomers, at low conversion, provided soluble polymers consisting of hydrocarbon macromolecules with pendant eugenol moieties. At high conversions only cross-linked polymers were obtained, attributed to participation of the allylic double bonds in the polymerization reaction. In addition, copolymers of each eugenol derivative with ethyl methacrylate (EMA) were prepared at low conversion, with the copolymerization reaction studied by assuming the terminal model and the reactivity ratios determined according to linear and nonlinear methods. The values obtained were r(EgMA) = 1.48, r(EMA) = 0.55 and r(EEgMA) = 1.22, r(EMA) = 0.42. High molecular weight polymers and copolymers were obtained at low conversion. Analysis of thermal properties revealed a T(g) of 95 degrees C for PEgMA and of 20 degrees C for PEEgMA and an increase in the thermal stability for the eugenol derivatives polymers and copolymers with respect to that of PEMA. Water sorption of the copolymers was found to decrease with the eugenol derivative content. Both monomers EgMA and EEgMA showed antibacterial activity against Streptococcus mutans, producing inhibition halos of 7 and 21 mm, respectively. Finally, cell culture studies revealed that the copolymers did not leach any toxic eluants and showed good cellular proliferation with respect to PEMA. This study thus indicates

  6. Preparation of natural pyrite nanoparticles by high energy planetary ball milling as a nanocatalyst for heterogeneous Fenton process

    Energy Technology Data Exchange (ETDEWEB)

    Fathinia, Siavash [Department of Mining Engineering, Faculty of Engineering and Technology, Imam Khomeini International University, Qazvin (Iran, Islamic Republic of); Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of); Fathinia, Mehrangiz [Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of); Rahmani, Ali Akbar [Department of Mining Engineering, Faculty of Engineering and Technology, Imam Khomeini International University, Qazvin (Iran, Islamic Republic of); Khataee, Alireza, E-mail: a_khataee@tabrizu.ac.ir [Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)

    2015-02-01

    Graphical abstract: - Highlights: • Pyrite nanoparticles were successfully produced by planetary ball milling process. • The physical and chemical properties of pyrite nanoparticles were fully examined. • The degradation of AO7 was notably enhanced by pyrite nanoparticles Fenton system. • The influences of basic operational parameters were investigated using CCD. - Abstract: In the present study pyrite nanoparticles were prepared by high energy mechanical ball milling utilizing a planetary ball mill. Various pyrite samples were produced by changing the milling time from 2 h to 6 h, in the constant milling speed of 320 rpm. X-ray diffraction (XRD), scanning electron microscopy (SEM) linked with energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FT-IR) analysis and Brunauer–Emmett–Teller (BET) were performed to explain the characteristics of primary (unmilled) and milled pyrite samples. The average particle size distribution of the produced pyrite during 6 h milling was found to be between 20 nm and 100 nm. The catalytic performance of the different pyrite samples was examined in the heterogeneous Fenton process for degradation of C.I. Acid Orange 7 (AO7) solution. Results showed that the decolorization efficiency of AO7 in the presence of 6 h-milled pyrite sample was the highest. The impact of key parameters on the degradation efficiency of AO7 by pyrite nanoparticles catalyzed Fenton process was modeled using central composite design (CCD). Accordingly, the maximum removal efficiency of 96.30% was achieved at initial AO7 concentration of 16 mg/L, H{sub 2}O{sub 2} concentration of 5 mmol/L, catalyst amount of 0.5 g/L and reaction time of 25 min.

  7. Application of solid-liquid TPPBs to the production of L-phenylacetylcarbinol from benzaldehyde using Candida utilis.

    Science.gov (United States)

    Khan, Tanya R; Daugulis, Andrew J

    2010-11-01

    The biotransformation of benzaldehyde and glucose to L-phenylacetylcarbinol (PAC) using Candida utilis was demonstrated in a solid-liquid two-phase partitioning bioreactor (TPPB) with the aim of reducing substrate, product, and by-product toxicity via sequestration. Previous work in the field had used octanol as the sequestering phase of liquid-liquid TPPBs but was limited by the toxic effects of octanol on C. utilis. To improve solvent selection in any future studies, the critical log P of C. utilis was determined in the current study to be 4.8 and can be used to predict biocompatible solvents. Bioavailability tests showed alkanes and alkenes to be non-bioavailable. As polymers are biocompatible and non-bioavailable, a wide range of commercially available polymers was screened and it was demonstrated that polymer softness plays a key role in absorptive capability. The polymer Hytrel G3548L was selected as the second phase to sequester benzaldehyde, PAC, and benzyl alcohol, with partition coefficients of 35, 7.5, and 10, respectively. With a 9% by volume partitioning phase, 13.6 g/L biomass of C. utilis achieved an overall PAC concentration of 11 g/L, a 1.9-fold improvement over the single-phase case. Benzyl alcohol concentration was 4.5 g/L, a 1.6-fold reduction. The volumetric productivity was 0.85 g/L h, a 1.2-fold improvement over the single-phase system. These results demonstrate a promising starting point for solid-liquid TPPBs for PAC production. © 2010 Wiley Periodicals, Inc.

  8. Increasing the thermal storage capacity of a phase change material by encapsulation: preparation and application in natural rubber.

    Science.gov (United States)

    Phadungphatthanakoon, Songpon; Poompradub, Sirilux; Wanichwecharungruang, Supason P

    2011-09-01

    Existing encapsulated organic phase change materials (PCM) usually contain a shell material that possesses a poor heat storage capacity and so results in a lowered latent heat storage density of the encapsulated PCM compared to unencapsulated PCM. Here, we demonstrate the use of a novel microencapsulation process to encapsulate n-eicosane (C20) into a 2:1 (w/w) ratio blend of ethyl cellulose (EC):methyl cellulose (MC) to give C20-loaded EC/MC microspheres with an increased heat storage capacity compared to the unencapsulated C20. Up to a 29 and 24% increase in the absolute enthalpy value during crystallization and melting were observed for the encap-C20/EC/MC microparticles with a 9% (w/w) EC/MC polymer content. The mechanism that leads to the increased latent heat storage capacity is discussed. The blending of the water-dispersible C20-loaded EC/MC microspheres into natural rubber latex showed excellent compatibility, and the obtained rubber composite showed not only an obvious thermoregulation property but also an improved mechanical property.

  9. Characterization of the Bacterial Community Naturally Present on Commercially Grown Basil Leaves: Evaluation of Sample Preparation Prior to Culture-Independent Techniques

    Directory of Open Access Journals (Sweden)

    Siele Ceuppens

    2015-08-01

    Full Text Available Fresh herbs such as basil constitute an important food commodity worldwide. Basil provides considerable culinary and health benefits, but has also been implicated in foodborne illnesses. The naturally occurring bacterial community on basil leaves is currently unknown, so the epiphytic bacterial community was investigated using the culture-independent techniques denaturing gradient gel electrophoresis (DGGE and next-generation sequencing (NGS. Sample preparation had a major influence on the results from DGGE and NGS: Novosphingobium was the dominant genus for three different basil batches obtained by maceration of basil leaves, while washing of the leaves yielded lower numbers but more variable dominant bacterial genera including Klebsiella, Pantoea, Flavobacterium, Sphingobacterium and Pseudomonas. During storage of basil, bacterial growth and shifts in the bacterial community were observed with DGGE and NGS. Spoilage was not associated with specific bacterial groups and presumably caused by physiological tissue deterioration and visual defects, rather than by bacterial growth.

  10. Preparation and characterization of bio resin natural tannin/poly (vinylidene fluoride): A high dielectric performance nano-composite for electrical storage

    Science.gov (United States)

    Abdalla, S.; Pizzi, A.; Al-Ghamdi, Maryam A.; AlWafi, Reem

    2017-09-01

    We have prepared films of polymer nano-composite (PNC) of poly [vinylidene-fluoride] (PVDF) and bio resin natural tannin (BRNT) nanoparticles. The α and γ electro-active phases were detected, and the addition of BRNT drastically increases the formation of the α-phase. Addition of BRNT produces up to 98% of electro-active phases. Robust electrostatic interactions arise between charges at the BRNT-surfaces, and differences in electron affinity between CH2 and CF2 groups created dielectric dipoles. The addition of BRNT has not only enhanced the formation of the electrically active phases but also makes each dipole in the phase has its specific characteristics for example its own relaxation time. The AC-electrical permittivity showed that the dielectric constant of 10%wt-BRNT nanoparticles in PVDF has a value 44 ε0, which is four times more than the dielectric constant of the as-prepared PVDF films. These data show the importance of these polymers as easy, flexible, and durable energy storage materials.

  11. Preparation and characterization of PbTi0{sub 3} ceramics modified by a natural mixture of rare earth oxides of xenotime

    Energy Technology Data Exchange (ETDEWEB)

    Baltazar-Rodrigues, Jair; Rodrigues Junior, Pedro; Cruz, Gerson K. da, E-mail: jbr@uepg.br [Universidade Estadual de Ponta Grossa (UEPG), PR (Brazil). Departamento de Fisica; Lente, Manuel H.; Eiras, Jose A. [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Departamento de Fisica

    2014-01-15

    Lead titanate ceramics modified by xenotime (Xm) with nominal composition (Pb, Xm)TiO{sub 3}, Xm 10 or 15 mol %, were prepared by the conventional oxide mixture technique. Xenotime is a natural mineral consisting of a mixture of rare earth oxides. Thermal, structural and electric properties were investigated through differential and gravimetric thermal analysis, X-ray diffraction and dielectric measurements as a function of temperature. The results of both compositions revealed a higher density and free of cracks ceramic body, compared to pure PbTiO{sub 3} prepared by the same procedure. On the other hand, the structural characteristics and Curie temperature are nearly the same as those of pure PbTiO{sub 3}. The hysteresis loop measured at room temperature revealed a hard ferroelectric material with coercive field of 10.7 kV/cm and a remanent polarization of 0.2 μC/cm{sup 2}. These finding reveal a material with properties that highlight potential to be used as electronic devices that operate at high temperature and high frequencies. (author)

  12. Synthesis, characterization, and thermal stability of novel poly(azomethine-urethane)s and polyphenol derivatives derived from 2,4-dihydroxy benzaldehyde and toluene-2,4-diisocyanate

    Energy Technology Data Exchange (ETDEWEB)

    Kaya, Ismet, E-mail: kayaismet@hotmail.com [Canakkale Onsekiz Mart University, Faculty of Sciences and Arts, Department of Chemistry, 17020, Canakkale (Turkey); Avc Latin-Small-Letter-Dotless-I , Ali [Celal Bayar University, Faculty of Sciences and Arts, Department of Chemistry, 45040, Manisa (Turkey)

    2012-03-15

    Graphical abstract: Black-Right-Pointing-Triangle Synthesis, characterization, and thermal stability of novel poly(azomethine-urethane)s and polyphenol derivatives derived from 2,4-dihydroxy benzaldehyde and toluene-2,4-diisocyanate. Highlights: Black-Right-Pointing-Pointer New pol(azomethine-urethane)s were synthesized. Black-Right-Pointing-Pointer PAMUs were converted to their polyphenol species by oxidative polymerization reaction with NaOCl. Black-Right-Pointing-Pointer The synthesized compounds were characterized by solubility tests, TGA and DSC. Black-Right-Pointing-Pointer T{sub g} values of PAMUs were between 137 and 178 Degree-Sign C and thermal stabilities of them were very good. Black-Right-Pointing-Pointer Obtained compounds can be promising candidates for aerospace applications. - Abstract: Up to date, only a few kinds of poly(azomethine-urethane)s (PAMUs) were synthesized and studied with thermal degradation steps. However, polyphenol based PAMUs including azomethine linkages have not been investigated yet. The polyurethanes were prepared by condensation reaction of 2,4-dihydroxybenzaldehyde (2,4-DHBA) with toluene-2,4-diisocyanate (TDI) under argon atmosphere. Synthesized polyurethane was converted to its poly(azomethine urethane) species (TP-2AP, TP-3AP, and TP-4AP) by graft copolymerization reactions with amino phenols (2-amino phenol, 3-amino phenol, and 4-amino phenol). Obtained poly(azomethine urethane)s were converted to their polyphenol species (P-TP-2AP, P-TP-3AP, and P-TP-4AP) by oxidative polymerization reaction (OP) using NaOCl as the oxidant. The structures of the obtained compounds were confirmed by FT-IR, UV-vis, {sup 1}H NMR, and {sup 13}C NMR techniques. The molecular weight distribution parameters of the synthesized compounds were determined by the size exclusion chromatography (SEC). The synthesized compounds were also characterized by solubility tests, TG-DTA, and DSC. Fluorescence measurements were carried out in various

  13. Preparation and Analytical Properties of 4-Hydroxybenzaldehyde, Biuret and Formaldehyde Terpolymer Resin

    Directory of Open Access Journals (Sweden)

    Bunian A. Shareef

    2014-01-01

    Full Text Available The chelating resin was synthesized by polycondensation reaction of 4-hydroxy benzaldehyde, formaldehyde and biuret under alkaline condition. The prepared resin was characterized by IR spectroscopy and 1HNMR spectroscopy. The resin sample was cured isothermally at 1200C.The DSC scans was measured for the prepared resin. The analytical evaluation of the prepared resin toward the studied ions (Hg2+, Ni2+ and Pb2+ using the batch method. It was employed to study selectivity of metal ion uptake in a different pH and different treatment time.

  14. INHIBITION OF Escherichia coli O157:H7 CONTAMINATION ON CHICKEN MEAT BY NATURAL VINEGAR PREPARED FROM BANANA PEEL AND COCONUT WATER

    Directory of Open Access Journals (Sweden)

    Miskiyah

    2016-03-01

    Full Text Available The use of vinegar as a natural preservative to inactivate microbial growth in meat was investigated. Vinegar was prepared from banana peel and coconut water, and the efficacy against Escherichia coli O157:H7 was tested. Chicken meat were treated with vinegar solution (equals to 1% acetic acid, acetic acid solutions (1%, and lactic acid solutions (2%, control (distilled water. Samples were soaked with acid solution treatment for 1 minute (1.125:1 w/v; chicken meat: solution treatment. Treated samples were inoculated with E. coli O157:H7 on the surface of the chicken meat, then left for 20 minutes for absorption of bacteria into the meat. Observation was done at 0, 3, 6, 9, and 12 days at low temperature storage, and at 0, 6, 12, 18, 24 hours at room temperature storage. The results showed that banana peel vinegar and coconut water vinegar were effective as natural preservative. In conclusion, the vinegar were potentially inhibited E. coli O157:H7 growth at chicken meat until 12 hours at room temperature storage and 9 days at cold temperatures.

  15. 苯甲醛改性双氰胺环氧固化剂的研究%Researches of benzaldehyde-modified dicyandiamide as curing agent for epoxy resin

    Institute of Scientific and Technical Information of China (English)

    程秀莲; 郭小伟; 杨艳玲

    2015-01-01

    A novel curing agent, the benzaldehyde-modified was prepared. The optimal synthesis conditions and curing conditions were studied. The results showed that the better processing conditions were as follows:pH value was 3-4,the mole ratio of dicyandiamide to benzaldehyde was 1.5:1, the reaction temperature and time were 95℃and 2 h,respectively, and the yield of modified dicyandiamide was up to 65.67%. The curing process and properties were investigated by testing the paint membrane hardness. When the modified dicyandiamide was used as the epoxy resin curing agent, the ratio of modified dicyandiamide to epoxy resin was 1 to 10, the curing temperature and time were 130℃ and 8 h, the paint membrane hardness HV1 was 47.52 and this curing temperature was 30℃ lower than that for dicyandiamide alone(160℃).%用苯甲醛对双氰胺进行改性,制备了一种新型改性双氰胺固化剂。对合成条件进行了优化,并对其固化条件进行了研究。结果表明,苯甲醛改性双氰胺的较佳工艺条件为pH值3~4,苯甲醛与双氰胺物质的量比为1∶1.5,于95℃,反应2 h,收率65.67%。通过测试涂层硬度来考察固化工艺与性能。作为环氧树脂固化剂单独使用时,与环氧树脂的质量比为1∶10,固化温度为130℃固化8 h 涂膜硬度HV1=47.52。比双氰胺体系固化温度(160℃)降低了30℃。

  16. Reaction pathway and transition state of the Zn-promoted Barbier-type reactions of benzaldehyde and benzophenone with allylic iodides

    Energy Technology Data Exchange (ETDEWEB)

    Yamataka, Hiroshi; Nishikawa, Kazuyoshi; Hanafusa, Terukiyo (Osaka Univ., Ibaraki (Japan). Inst. of Scientific and Industrial Research)

    1994-01-01

    The carbonyl-[sup 14]C kinetic isotope effects and the substituent effects on the reactivity of the Zn-promoted Barbier-type reaction of allyl iodide (3-iodo-1-propene) with benzaldehyde and benzophenone were determined in THF at 25degC. The observed normal carbon isotope effects as well as positive Hammett [rho] values suggest that the reactions go through a direct nucleophilic addition mechanism. No indication of the occurrence of electron transfer was obtained by enone isomerization and dehalogenation probe experiments. Diastereoselectivity in the reaction of crotyl iodide (1-iodo-2-butene) with benzaldehyde was low and independent of the substituent on aldehyde, consistent with the six-membered cyclic transition state. (author).

  17. Selective oxidation of toluene to benzaldehyde by O{sub 2} with visible light in barium(2+)- and calcium(2+)-exchanged zeolite Y

    Energy Technology Data Exchange (ETDEWEB)

    Sun, H.; Blatter, F.; Frei, H. [Lawrence Berkeley Lab., CA (United States)

    1994-08-24

    High selectivity has been demonstrted upon visible light induced oxygenation of toluene to benzaldehyde in alkaline earth exchanged zeolite Y. We attribute the tight product control to mainly two factors. One is access to the C{sub 6}H{sub 5}CH{sub 3}-O{sub 2} excited charge-transfer state by light of sufficiently long wavelength to prevent loss of product control by photofragmentation of primary products or by homolysis of the proposed hydroperoxide intermediate. The second is confinement of benzyl/HO{sub 2} radical pairs to the zeolite matrix cage, which suppresses indiscriminate attack of these radicals and forces them to combine. The Co{sup 3+}-catalyzed radical oxidation of toluene by O{sub 2} in solution used currently in an industrial process for benzaldehyde synthesis lacks this selectivity, mainly because of continued oxidation of the aldehyde to benzoic acid. 24 refs., 2 figs.

  18. The effects of polymer phase ratio and feeding strategy on solid-liquid TPPBs for the production of L-phenylacetylcarbinol from benzaldehyde using Candida utilis.

    Science.gov (United States)

    Khan, Tanya R; Daugulis, Andrew J

    2011-01-01

    To increase the bioproduction of L-phenylacetylcarbinol (PAC), a precursor molecule in the synthesis of the decongestants ephedrine and pseudoephedrine and which suffers from substrate, product, and by-product inhibition, by ensuring that the delivery of the substrate, benzaldehyde, is maintained within a strict concentration window. Beads of the commercial polymer, Hytrel G3548L, can act as a sequestering phase to reduce inhibitory effects to cells of Candida utilis while creating a reservoir for high concentrations of products. In this work we varied the polymer phase volume ratio (from 3 to 15%), and modified the benzaldehyde feeding strategy to further improve on system performance, resulting in greater than 100% increase in the PAC productivity relative to a single phase control, as well as robust operation of the two-phase bioreactor with minimal operator intervention.

  19. An Efficient Preparation of 1,2-Diamino-1-phenylheptane

    Directory of Open Access Journals (Sweden)

    P. T. Perumal

    2002-06-01

    Full Text Available A convenient four-step method for the preparation of the lipophilic vicinal diamine 1,2-diamino-1-phenylheptane is described. Condensation involving octan-2-one, benzaldehyde and ammonia is reported. Regioselective Schmidt rearrangement of 2,6-diphenyl-3-pentyl-piperidin-4-one (1 to 2,7-diphenyl-3-pentyl hexahydrodiazapin-5-one (3 is presented. Hydrolysis of 2,7-diphenyl-3-pentyl hexahydrodiazapin-5-one to 1,2-diamino-1-phenylheptane (4 is also reported for the first time.

  20. Enantiopure inherently chiral calix[4]arene derivatives containing quinolin-2-yl-methanol moiety:Synthesis and application in the catalytic asymmetric addition of diethylzinc to benzaldehyde

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A series of novel N,O-type chiral ligands derived from enantiopure inherently chiral calix[4]arenes containing quinolin-2-yl-methanol moiety in the cone or partialcone conformation have been synthe-sized and characterized. Moreover,they have been applied to the catalytic asymmetric addition of diethylzinc to benzaldehyde,which represents the first example that the inherently chiral calixarene can be used as the chiral ligands for the catalytic asymmetric synthesis.

  1. Fe-catalyzed novel domino isomerization/cyclodehydration of substituted 2-[(indoline-3-ylidene)(methyl)]benzaldehyde derivatives: an efficient approach toward benzo[b]carbazole derivatives.

    Science.gov (United States)

    Paul, Kartick; Bera, Krishnendu; Jalal, Swapnadeep; Sarkar, Soumen; Jana, Umasish

    2014-04-18

    A new and efficient protocol to synthesize substituted benzo[b]carbazole derivatives has been demonstrated involving iron-catalyzed domino isomerization/cyclodehydration sequences from substituted 2-[(indoline-3-ylidene)(methyl)]benzaldehyde derivatives. The substrates could be easily made via Pd-catalyzed domino Heck-Suzuki coupling from 2-bromo-N-propargylanilide derivatives in high yields. Notably, the generality and efficiency of this two-stage domino strategy was further exemplified by the synthesis of a polycyclic benzofuran derivative.

  2. Suitable combination of promoter and micellar catalyst for kilo fold rate acceleration on benzaldehyde to benzoic acid conversion in aqueous media at room temperature: a kinetic approach.

    Science.gov (United States)

    Ghosh, Aniruddha; Saha, Rumpa; Ghosh, Sumanta K; Mukherjee, Kakali; Saha, Bidyut

    2013-05-15

    The kinetics of oxidation of benzaldehyde by chromic acid in aqueous and aqueous surfactant (sodium dodecyl sulfate, SDS, alkyl phenyl polyethylene glycol, Triton X-100 and N-cetylpyridinium chloride, CPC) media have been investigated in the presence of promoter at 303 K. The pseudo-first-order rate constants (kobs) were determined from a logarithmic plot of absorbance as a function time. The rate constants were found to increase with introduction of heteroaromatic nitrogen base promoters such as Picolinic acid (PA), 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen). The product benzoic acid has been characterized by conventional melting point experiment, NMR, HRMS and FTIR spectral analysis. The mechanism of both unpromoted and promoted reaction path has been proposed for the reaction. In presence of the anionic surfactant SDS, cationic surfactant CPC and neutral surfactant TX-100 the reaction can undergo simultaneously in both aqueous and micellar phase with an enhanced rate of oxidation in the micellar phase. Both SDS and TX-100 produce normal micellar effect whereas CPC produce reverse micellar effect in the presence of benzaldehyde. The observed net enhancement of rate effects has been explained by considering the hydrophobic and electrostatic interaction between the surfactants and reactants. SDS and bipy combination is the suitable one for benzaldehyde oxidation.

  3. Preparation and Characterization of Marble Powder/Natural Rubber Composites%大理石粉/NR复合材料的制备与性能研究

    Institute of Scientific and Technical Information of China (English)

    王继虎; 陈有双; 唐忠锋; 陶冶

    2011-01-01

    将石材加工过程中产生的废弃大理石粉碎,采用硬脂酸偶联剂对大理石粉进行改性.将改性后大理石粉混炼到NR中制备复合材料,通过不同测试手段研究材料的性能变化.结果表明,球磨后大理石粉的平均粒径为24.18μm.采用硬脂酸改性后大理石粉添加量为10%时性能最佳,拉伸强度达到20.11MPa.与大理石/NR及纯橡胶材料相比,改性后大理石粉/NR复合材料的耐热性能明显提高.活化后大理石粉作为橡胶填料,可替代炭黑降低橡胶制品生产成本,同时有利于环保.%Marble powder was modified by stearic acid coupling agent after marble scraps were grinded. Natural rubber/marble powder composites were prepared by direct blending technology. The results showed that the average particle size of marble powder was 24.18μm. The best mechanical properties of composites were obtained after modified marble powder content were 10 percent in the natural rubber, and the tensile strength was 20.11 Mpa. The heat resistance of composites was higher than unmodified marble powder/NR composites. Activated marble powder has excellent reinforcement effect and ideal processing characteristics, and can replace carbon black in rubber to achieve its application.

  4. Simultaneous determination of paracetamol, 4-Aminophenol, 4-Chloroacetanilid, Benzyl alcohol,Benzaldehyde and EDTA by HPLC methodin paracetamol injection ampoule

    Directory of Open Access Journals (Sweden)

    Ali Merrikhi Khosroshahi

    2016-06-01

    Full Text Available Paracetamol that is known as acetaminophen have the most consume as an analgesic and antipyretic drug in the world. That is formulated in single compound or mixture at many forms such as tablets, syrups, suspensions and drops. The last form is intravenous injections. Paracetamol derived from 4-minophenol which is synthesized by acylated the P-acetaminophenol and acetic anhydride. 4-aminophenol is the main impurity at manufacturing of paracetamol which could produce by hydrolysis during storage or synthesis under normal conditions (temperature, pH, etc.. Also, 4-chloroacetanilid may be observed as an impurity in the raw material of paracetamol synthesis. Benzyl alcohol is a preservative that used in Paracetamol for injection. It will be very important if there are analytical techniques to measuring paracetamol and its degradation products accurately and easily. Undoubtedly the most important and widely used, separation technique is chromatography. There are several reports about separation and quantitative determination of paracetamol lonely or simultaneous determination of paracetamol and 4-aminophenol. In this paper investigated simultaneous determination of paracetamol, 4-aminophenol, 4-chloroacetanilid, benzyl alcohol, benzaldehyde, and EDTA in paracetamol for injection ampoules by high performance liquid chromatography. By changing the ratio of mixing methanol and acetonitrile as mobile phase at the wavelength of 215 nm and pH=3 separation of all compounds were completely done.

  5. The Cytotoxicity of Benzaldehyde Nitrogen Mustard-2-Pyridine Carboxylic Acid Hydrazone Being Involved in Topoisomerase IIα Inhibition

    Directory of Open Access Journals (Sweden)

    Yun Fu

    2014-01-01

    Full Text Available The antitumor property of iron chelators and aromatic nitrogen mustard derivatives has been well documented. Combination of the two pharmacophores in one molecule in drug designation is worth to be explored. We reported previously the syntheses and preliminary cytotoxicity evaluation of benzaldehyde nitrogen mustard pyridine carboxyl acid hydrazones (BNMPH as extended study, more tumor cell lines (IC50 for HepG2: 26.1 ± 3.5 μM , HCT-116: 57.5 ± 5.3 μM, K562: 48.2 ± 4.0 μM, and PC-12: 19.4 ± 2.2 μM were used to investigate its cytotoxicity and potential mechanism. In vitro experimental data showed that the BNMPH chelating Fe2+ caused a large number of ROS formations which led to DNA cleavage, and this was further supported by comet assay, implying that ROS might be involved in the cytotoxicity of BNMPH. The ROS induced changes of apoptosis related genes, but the TFR1 and NDRG1 metastatic genes were not obviously regulated, prompting that BNMPH might not be able to deprive Fe2+ of ribonucleotide reductase. The BNMPH induced S phase arrest was different from that of iron chelators (G1 and alkylating agents (G2. BNMPH also exhibited its inhibition of human topoisomerase IIα. Those revealed that the cytotoxic mechanism of the BNMPH could stem from both the topoisomerase II inhibition, ROS generation and DNA alkylation.

  6. Using heavy atom rare gas matrix to control the reactivity of 4-methoxybenzaldehyde: A comparison with benzaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Kus, Nihal [Department of Chemistry, University of Coimbra, 3004-535 Coimbra (Portugal); Department of Physics, Anadolu University, 26470 Eskisehir (Turkey); Sharma, Archna; Reva, Igor; Fausto, Rui [Department of Chemistry, University of Coimbra, 3004-535 Coimbra (Portugal); Lapinski, Leszek [Institute of Physics, Polish Academy of Sciences, Warsaw (Poland)

    2012-04-14

    Different patterns of photochemical behavior were observed for 4-methoxybenzaldehyde (p-anisaldehyde) isolated in xenon and in argon matrices. Monomers of the compound isolated in solid Xe decarbonylate upon middle ultraviolet irradiation, yielding methoxybenzene (anisole), and CO. On the other hand, p-anisaldehyde isolated in an Ar matrix and subjected to identical irradiation, predominantly isomerizes to the closed-ring isomeric ketene (4-methoxycyclohexa-2,4-dien-1-ylidene) methanone. Experimental detection of a closed-ring ketene photoproduct, generated from an aromatic aldehyde, constitutes a rare observation. The difference between the patterns of photochemical transformations of p-anisaldehyde isolated in argon and xenon environments can be attributed to the external heavy-atom effect, where xenon enhances the rate of intersystem crossing from the singlet to the triplet manifold in which decarbonylation (via p-methoxybenzoyl radical) takes place. The parent compound, benzaldehyde, decarbonylates (to benzene + CO) when subjected to middle ultraviolet irradiation in both argon and xenon matrices. This demonstrates the role of the methoxy p-anisaldehyde substituent in activation of the reaction channel leading to the formation of the ketene photoproduct.

  7. Manufacturing by-products from, and stereochemical outcomes of the biotransformation of benzaldehyde used in the synthesis of methamphetamine.

    Science.gov (United States)

    Cox, Matthew; Klass, Gunter; Koo, Christina Wei Min

    2009-08-10

    Clandestine synthesis of methamphetamine in Australia has predominantly started from pseudoephedrine extracted from over the counter cold and flu medications. However, recently introduced restrictions on the sale of these products have made pseudoephedrine much more difficult to obtain. As a result clandestine chemists have had to resort to other means of obtaining the necessary chemical precursors. A recent drug raid (Adelaide, January 2008) resulted in the seizure of an unusual reaction mixture that indicated a novel approach involving the fermentation of glucose by yeast in the presence of benzaldehyde to give 1-hydroxy-1-phenylpropanone, also known as l-phenylacetylcarbinol (l-PAC), a known precursor to ephedrine and pseudoephedrine and hence methamphetamine. A study was undertaken into this process with the aim of determining the characteristic reaction by-products associated with methamphetamine made in this way. The study also looked at the stereochemical selectivity of the fermentation reaction and the stereochemistry of the subsequent reaction products, ephedrine and pseudoephedrine, and the final methamphetamine.

  8. Synthesis, X-ray structure analysis, thermodynamic and electronic properties of 4-acetamido benzaldehyde using vibrational spectroscopy and DFT calculations

    Science.gov (United States)

    Jeeva Jasmine, N.; Arunagiri, C.; Subashini, A.; Stanley, N.; Thomas Muthiah, P.

    2017-02-01

    Theoretical Spectrograms, namely, FT-Raman (3500-50 cm-1) and FT-Infrared (4000-400 cm-1) spectra have been studied for 4-acetamido benzaldehyde (4ABA) and are assigned to different normal modes of the molecule. Vibrational spectral analysis was compared with the experimental and theoretical, FT-IR and FT-Raman spectra. The effect of polarity on the Harmonic vibrational frequencies, intensities, optimized geometrical parameters and several thermodynamic parameters in the ground state have been computed by the B3LYP method using 6-311 + G(d,p) basis set. The results of the optimized molecular structure is presented and compared with the XRD values. The global chemical reactivity relate to some parameters, such as HOMO, LUMO, gap energy (ΔE) and other parameters, including electronegativity (χ) and global hardness (η). The values of the reactivity descriptors indicated that the interaction between 4ABA molecules reduced its reactivity in comparison with the exhibited in gas phase. In addition, the local reactivity has been analyzed through the Fukui function and condensed softness indices.

  9. A nanoporous 3D zinc(II) metal-organic framework for selective absorption of benzaldehyde and formaldehyde

    Science.gov (United States)

    Moradpour, Tahereh; Abbasi, Alireza; Van Hecke, Kristof

    2015-08-01

    A new 3D nanoporous metal-organic framework (MOF), [[Zn4O(C24H15N6O6)2(H2O)2]·6H2O·DMF]n (1) based on 4,4‧,4″-s-triazine-1,3,5-triyltri-p-aminobenzoate (TATAB) ligand was solvothermally synthesized and characterized by single-crystal X-ray diffraction, Powder X-ray diffraction (PXRD), infrared spectroscopy (IR) and Brunauer-Emmett-Teller (BET) analyses. X-ray single crystal diffraction analysis reveals that 1 exhibits a 3D network with new kvh1 topology. Semi-empirical (AM1) calculations were carried out to obtain stable conformers for TATAB ligand. In addition, the absorption of two typical aldehydes (benzaldehyde and formaldehyde) in the presence of 1 was investigated and the effect of the aldehyde concentration, exposure time and temperature was studied. It was found that compound 1 has a potential for the absorption of aldehydes under mild conditions.

  10. The cytotoxicity of benzaldehyde nitrogen mustard-2-pyridine carboxylic acid hydrazone being involved in topoisomerase IIα inhibition.

    Science.gov (United States)

    Fu, Yun; Zhou, Sufeng; Liu, Youxun; Yang, Yingli; Sun, Xingzhi; Li, Changzheng

    2014-01-01

    The antitumor property of iron chelators and aromatic nitrogen mustard derivatives has been well documented. Combination of the two pharmacophores in one molecule in drug designation is worth to be explored. We reported previously the syntheses and preliminary cytotoxicity evaluation of benzaldehyde nitrogen mustard pyridine carboxyl acid hydrazones (BNMPH) as extended study, more tumor cell lines (IC50 for HepG2: 26.1 ± 3.5 μM, HCT-116: 57.5 ± 5.3 μM, K562: 48.2 ± 4.0 μM, and PC-12: 19.4 ± 2.2 μM) were used to investigate its cytotoxicity and potential mechanism. In vitro experimental data showed that the BNMPH chelating Fe(2+) caused a large number of ROS formations which led to DNA cleavage, and this was further supported by comet assay, implying that ROS might be involved in the cytotoxicity of BNMPH. The ROS induced changes of apoptosis related genes, but the TFR1 and NDRG1 metastatic genes were not obviously regulated, prompting that BNMPH might not be able to deprive Fe(2+) of ribonucleotide reductase. The BNMPH induced S phase arrest was different from that of iron chelators (G1) and alkylating agents (G2). BNMPH also exhibited its inhibition of human topoisomerase IIα. Those revealed that the cytotoxic mechanism of the BNMPH could stem from both the topoisomerase II inhibition, ROS generation and DNA alkylation.

  11. Growth and characterization of benzaldehyde 4-nitro phenyl hydrazone (BPH) single crystal: A proficient second order nonlinear optical material

    Science.gov (United States)

    Saravanan, M.; Abraham Rajasekar, S.

    2016-04-01

    The crystals (benzaldehyde 4-nitro phenyl hydrazone (BPH)) appropriate for NLO appliance were grown by the slow cooling method. The solubility and metastable zone width measurement of BPH specimen was studied. The material crystallizes in the monoclinic crystal system with noncentrosymmetric space group of Cc. The optical precision in the whole visible region was found to be excellent for non-linear optical claim. Excellence of the grown crystal is ascertained by the HRXRD and etching studies. Laser Damage Threshold and Photoluminescence studies designate that the grown crystal contains less imperfection. The mechanical behaviour of BPH sample at different temperatures was investigated to determine the hardness stability of the grown specimen. The piezoelectric temperament and the relative Second Harmonic Generation (for diverse particle sizes) of the material were also studied. The dielectric studies were executed at varied temperatures and frequencies to investigate the electrical properties. Photoconductivity measurement enumerates consummate of inducing dipoles due to strong incident radiation and also divulge the nonlinear behaviour of the material. The third order nonlinear optical properties of BPH crystals were deliberate by Z-scan method.

  12. 一种天然清洁剂的制备及其性能研究%Study on Preparation and Properties of A Natural Detergent

    Institute of Scientific and Technical Information of China (English)

    贾晓伟; 韩振武; 高何敏; 普蜃翕; 赵成爱

    2016-01-01

    采用地肤子超声水提液为主要材料,研究了一种天然油污清洁剂的制备工艺。通过正交试验,确定了最佳配方。地肤子清洁剂的最佳配方:地肤子超声水提液的浓度为2.00 g/mL,脂肪醇聚氧乙烯醚硫酸铵( ALES)的浓度为8.00 g/mL。测试了该清洁剂的清洁度,抑菌率,稳定性,粘度,起泡性,试验结果表明地肤子清洁剂有较强的清洁能力,有很大的市场前景。%With Fructus Kochiae ultrasonic water extract as main materials, the preparation process of a natural oil cleaning agent was studied. Through orthogonal test, the optimum formulation was found. The optimum formula of Kochiascoparia cleaner was as follows: Fructus Kochiae ultrasonic water provided the concentration of 2. 00 g/mL. The concentration of fatty alcohol polyoxyethylene ether sulfur acid ammonium ( ALES ) was 8. 00 g/mL. Testing the cleanliness of the cleaning agent, antibacterial rate, stability, viscosity, foaming, the test results showed that Fructus Kochiae cleaner had strong cleaning ability and great market prospects.

  13. Evidence for a solvent-induced change in rate-limiting step in the hydrolysis of benzaldehyde dimethyl acetal

    Energy Technology Data Exchange (ETDEWEB)

    Young, P.R.; Bogseth, R.C.; Rietz, E.G.

    1980-09-24

    Secondary deuterium isotope effects for the hydrolysis of the dimethyl acetal of benzaldehyde-formyl-d have been determined in mixed water-dioxane solvents varying between pure water and 70% dioxane, 30% water, by volume. Between 0 and 20% dioxane, the isotope effect (k/sup H//k/sup D/) decreases from 1.12 to 1.06. Between 20 and 70% added dioxane, the isotope effects increase regularly from 1.06 to 1.15. The decrease in the apparent isotope effect at low concentrations of dioxane may be an artifact of the biphasic kinetics observed due to hemiacetal buildup in the more aqueous media. The increases in k/sup H//k/sup D/ that are observed between 20 and 70% dioxane are interpreted in terms of a change in rate-limiting step from C-O bond cleavage in water to rate-limiting diffusion apart of the alcohol-oxocarbonium ion encounter pair in high concentrations of dioxane. On the basis of this assumption, ratios of the rate constants for internal return and diffusional separation of the complex are estimated. The steady decrease in rho and rho/sup r/ within the series water and 50 and 70% dioxane also suggests an increase in cationic character in the rate-limiting transition state. Isolated resonance structure-reactivity parameters (rho/sup r//rho/sub eq//sup r/) provide estimates of sp/sup 2/ character in rate-limiting transition states that are essentially identical with the estimates obtained from the secondary isotope effect studies.

  14. Preparation and Application of Perchloric Acid Supported on Alumina (Al2O3-HCIO4) to the Synthesis of α-(α-Amidobenzyl)-β-naphthols

    Institute of Scientific and Technical Information of China (English)

    SHATERIAN,Hamid Reza; KHORAMI,Fahimeh; AMIRZADEH,Azita; GHASHANG,Majid

    2009-01-01

    Preparation of perchloric acid supported on alumina and its primary application as a solid supported heterogeneous catalyst to the synthesis of α-(α-amidobenzyl)-β-naphthols by a one-pot,three-component condensation of benzaldehydes,β-naphthol and acetamide or benzamide under thermal solvent-free conditions were described.The present methodology offers several advantages such as simple procedure,shorter reaction time,and excellent yields.

  15. Evidence of coupled photoinduced proton transfer and intramolecular charge transfer reaction in para-N,N-dimethylamino orthohydroxy benzaldehyde: Spectroscopic and theoretical studies

    Energy Technology Data Exchange (ETDEWEB)

    Mahanta, Subrata; Singh, Rupashree Balia; Kar, Samiran [Department of Chemistry, University of Calcutta, 92, A.P.C. Road, Kolkata 700009 (India); Guchhait, Nikhil [Department of Chemistry, University of Calcutta, 92, A.P.C. Road, Kolkata 700009 (India)], E-mail: nguchhait@yahoo.com

    2008-12-10

    Steady state and time resolved fluorescence spectroscopy and quantum chemical calculations have been used to study excited state properties of para-N,N-dimethylamino orthohydroxy benzaldehyde (PDOHBA). Spectral characteristics of PDOHBA support the existence of both donor-acceptor charge transfer (CT) and proton transfer (PT) reaction in the excited state. Structural calculations at Hartree Fock and Density Functional Theory (DFT) levels and theoretical potential energy surfaces (PESs) along the proton transfer and donor twisting coordinates using DFT and Time Dependent Density Functional Theory point towards the possibility of barrierless PT and CT reaction in the first excited state of PDOHBA.

  16. The Production of Benzaldehyde by Rhizopus oligosporus USM R1 in a Solid State Fermentation (SSF) System of Soy Bean Meal: Rice Husks

    OpenAIRE

    Norliza, A. W.; Ibrahim, C. O.

    2005-01-01

    The cultivation of Rhizopus oligosporus USM R1 for the production of benzaldehyde, a bitter cherry almond flavour was performed using soya bean meal and rice husks as the substrates. The identification of R. oligosporus USM R1 was performed based on the observation made under light microscope and scanning electron microscope (SEM). The optimum conditions for the SSF in a 250-ml Erlenmeyer flask system were 40% (v/w) water content, substrate particle size of 0.7 mm; inoculum size of 1 x 10^5 s...

  17. Influence of basic properties of Mg,Al-mixed oxides on their catalytic activity in knoevenagel condensation between benzaldehyde and phenylsulfonylacetonitrile

    Directory of Open Access Journals (Sweden)

    Caridad Noda Pérez

    2009-01-01

    Full Text Available The catalytic performance of Mg,Al-mixed oxides (MO20, MO25 and MO33 derived from hydrotalcites was evaluated in the Knoevenagel reaction between benzaldehyde and phenylsulfonylacetonitrile at 373 and 383 K. The best results were obtained for the sample MO20 that presented the highest basic sites density and external area and the smallest crystallite sizes. The relative amount of basic sites with weak to intermediate strength also played an important role on catalytic performance. By increasing the catalyst content from 1 to 5 wt.% at 383 K, a complete conversion of the reactants is attained, producing α-phenylsulfonylcinnamonitrile with a selectivity of 100%.

  18. Density, Viscosity, Sound Speed, and Thermoacoustical Parameters of Benzaldehyde with Chlorobenzene or Nitrobenzene at 303.15 K, 308.15 K, and 313.15 K

    Science.gov (United States)

    Lavanya, T. G.; Saravanakumar, K.; Baskaran, R.; Kubendran, T. R.

    2013-07-01

    The values of the density, viscosity, and speed of sound for binary liquid mixtures of benzaldehyde with chlorobenzene or nitrobenzene have been measured over the entire range of composition at (303.15, 308.15, and 313.15) K. These values have been used to calculate the excess molar volume (), and excess free volume (). McAllister's three-body interaction model is used for correlating the kinematic viscosity of binary mixtures. The thermophysical properties (density, viscosity, and ultrasonic velocity) under study were fit to the Jouyban-Acree model.

  19. Pestalols A-E, new alkenyl phenol and benzaldehyde derivatives from endophytic fungus Pestalotiopsis sp. AcBC2 isolated from the Chinese mangrove plant Aegiceras corniculatum.

    Science.gov (United States)

    Sun, Jian-Fan; Lin, Xiuping; Zhou, Xue-Feng; Wan, Junting; Zhang, Tianyu; Yang, Bin; Yang, Xian-Wen; Tu, Zhengchao; Liu, Yonghong

    2014-06-01

    Five alkenyl phenol and benzaldehyde derivatives, pestalols A-E (1-5), as well as seven known compounds (6-12), were isolated from endophytic fungus Pestalotiopsis sp. AcBC2 derived from the Chinese mangrove plant Aegiceras corniculatum. Their structures were determined by spectroscopic analyses. Compounds 2 and 3 showed cytotoxicity against a panel of 10 tumor cell lines. Compounds 1-5, 8, 9, 11, and 12 showed inhibitory activities against Influenza A virus subtype (H3N2) and Swine Flu (H1N1) viruses. Compound 2 also showed inhibitory activity against tuberculosis.

  20. Synthesis of Chalcone and Flavanone Compound Using Raw Material of Acetophenone and Benzaldehyde Derivative

    Directory of Open Access Journals (Sweden)

    Ismiyarto Ismiyarto

    2010-06-01

    Full Text Available Synthesis of flavanoid compounds of chalcone and flavanone groups have been conducted. Flavanoid Is one of the group natural products which is mostly found in plants and have been proved to have physiological activity as drug. In this research, chalcone proup compounds that being synthesized are: chalcone, 3,4-dimethoxychalcone, 2'-hidroxy-3,4-dimethoxychalcone where as compound of flavanone group that being synthesized is 3',4'-dimethoxyflavanone. The synthesis of chalcone group are carried out based on Claisen-Schmidt reaction by using raw material of aromatic aldehydes and aromatic ketones. The synthesis in carried out by stirring at the room temperature using alkali solution as catalyst and ethanol as solvent. The synthesis of 3',4'-dimethoxyflanone is made based on the nucleophilic 1,4 addition of the unsaturated α,β ketone. The synthesis is made by refluxing 2'-hydroxy-3,4-dimethoxychalcone in alkali condition for 12 hours. The identification of flavanoid compound is carried out by using spectroscopic IR, GC-MS and 1H-NMR methods. The result of each synthesis chalcone group are follows: chalcone as yellowish solid with m.p= 50 °C and the yield is 83.39%; 3,4-dimethoxychalcone as yellow solid with m.p= 57°C and the yield is 76.00% ; 2'-hydroxy-3,4-dimethoxychalcone as orange solid with m.p= 90 °C and the yield is 74.29%, for 3',4'-dimethoxyflavanone as pale yellow solid with m.p= 80 °C and the yield is 72.00%.

  1. Preparation and Mechanical Properties of Natural Rubber Composites%天然橡胶复合材料制备及力学性能研究

    Institute of Scientific and Technical Information of China (English)

    袁霞; 许健; 安玉良; 于万年; 韩德仁

    2014-01-01

    The preparation and mechanical properties of natural rubber composite was carried out by using different kinds of enhancer such as white carbon black, carbon nanotube, carbon microsphere and graphene. Using traditional mechanical mixing method to mix the raw materials and then the composite was synthesized by heat condition on the plat sulfuration apparatus. The effects of the content of enhancer on mechanism perfor-mance of composite were investigated and then the optimized content of enhancer was obtained. The effects law of the content of enhancer on the ten-sile strength of composites was investigated. The general tensile tester and sclerometer were used to characterize the hardness and mechanism perfor-mance of the composites. The results showed the mechanism properties of composites became stronger with the increasing of the carbon microsphere, carbon nanotube and grapheme, and became weakness with the increasing of white carbon black. The carbon nanotube and grapheme were better en-hancers for the rubber.%分别以白炭黑、碳纳米管、碳微球及石墨烯为增强剂,对天然橡胶复合材料的制备以及其力学性能进行研究。采用传统机械混炼法将复合材料进行混合,通过平板硫化机进行交联制备天然橡胶复合材料。分别考察不同增强剂的含量对橡胶复合材料力学性能的影响,找到最佳的添加量。分析了不同种增强剂对复合材料力学性能的影响规律,对其增强效果进行对比说明。采用电子万能拉伸测试仪、邵氏硬度计对复合材料的拉伸性能和硬度性能进行分析,结果表明:复合材料的力学性能随着炭微球、碳纳米管和石墨烯含量的增加而增加,随着白炭黑的含量的增加而减少,碳纳米管和石墨烯的增强效果较好。

  2. [Application of gas chromatography-high resolution quadrupole time of flight mass spectrometry to the analysis of benzaldehyde, benzyl alcohol acetophenone and phenylacetaldehyde in complex aromatic samples].

    Science.gov (United States)

    Liu, Junyan; Cao, Zhe; Li, Jiwen; Wang, Zheming; Wang, Chuan; Gu, Songyuan

    2015-02-01

    The study focuses on the quantitative analytical characterization of benzaldehyde, benzyl alcohol, acetophenone and phenylacetaldehyde in complex aromatic samples by gas chromatography-high resolution quadrupole time of flight mass spectrometry (GC-QTOF MS). The four compounds in real sample were accurately qualified and quantified through a comprehensive analysis of the GC retention times and the accurate masses of the ion fragments obtained by the high resolution MS. The new method therefore effectively avoids the interference of the real sample substrate, which reduces the accuracy of the analysis results. The peak area of the characteristic ion fragment for each compound was used for quantitation calculation. The MS signal responses of the four compounds showed good linear relationships with the corresponding mass concentrations and the linear regression coefficients were greater than 0. 99. The method recoveries were 87. 97% - 103.01%. The limits of detection (LODs) were 0. 01, 0. 03, 0. 02 and 0. 01 mg/L for benzaldehyde, benzyl alcohol, acetophenone and phenylacetaldehyde respectively. The contents of the four compounds in three real samples were analyzed. The study provided a new strategy for oxygenate analysis in complex aromatic samples using GC-QTOF MS. By measuring the accurate masses, the new method reduces the reliance on chromatographic separation ability and makes up the shortcomings of the traditional GC-MS methods.

  3. Enzymatic reduction of 4-(dimethylamino)benzaldehyde with carrot bits (Daucus carota): a simple experiment for understanding biocatalysis; Reducao enzimatica do 4-(dimetilamino)benzaldeido com pedacos de cenoura (Daucus carota): um experimento simples na compreensao da biocatalise

    Energy Technology Data Exchange (ETDEWEB)

    Omori, Alvaro Takeo; Portas, Viviane Barbosa; Oliveira, Camila de Souza de, E-mail: alvaro.omori@ufabc.edu.br [Centro de Ciencias Naturais e Humanas, Universidade Federal do ABC, SP (Brazil)

    2012-07-01

    The present paper describes a simple, low-costly and environmentally friendly procedure for reduction of 4-(dimethylamino)benzaldehyde using carrot bits in water. This interdisciplinary experiment can be used to introduce the concepts of biocatalysis and green chemistry to undergraduate students. (author)

  4. OZONE REACTION WITH N-ALDEHYDES (N=4-10), BENZALDEHYDE, ETHANOL, ISOPROPANOL, AND N-PROPANOL ADSORBED ON A DUAL-BED GRAPHITIZED CARBON/CARBON MOLECULAR SIEVE ADSORBENT CARTRIDGE

    Science.gov (United States)

    Ozone reacts with n-aldehydes (n = 4 - 10), benzaldehyde, ethanol, isopropanol, and n-propanol adsorbed on a dual-bed graphitized carbon/carbon molecular sieve adsorbent cartridge. Destruction of n-aldehydes increases with n number and with ozone concentration. In some samp...

  5. Benzaldehyde thiosemicarbazone monohydrate

    Directory of Open Access Journals (Sweden)

    Sheng-Jiu Gu

    2008-08-01

    Full Text Available In the title compound, C8H9N3S·H2O, intramolecular N—H...N hydrogen bonding contributes to the molecular conformation. Water molecules are involved in intermolecular N—H...O and O—H...S hydrogen bonds, which link the molecules into ribbons extended along the a axis. Weak intermolecular N—H...S hydrogen bonds link these ribbons into layers parallel to the ab plane with the phenyl rings pointing up and down.

  6. Electronic properties and the nature of metal–insulator transition in NdNiO{sub 3} prepared at ambient oxygen pressure

    Energy Technology Data Exchange (ETDEWEB)

    Hooda, M.K.; Yadav, C.S., E-mail: shkehar@iitmandi.ac.in

    2016-06-15

    We report the electronic properties of the NdNiO{sub 3}, prepared at the ambient oxygen pressure condition. The metal–insulator transition temperature is observed at 192 K, but the low temperature state is found to be less insulating compared to the NdNiO{sub 3} prepared at high oxygen pressure. The electric resistivity, Seebeck coefficient and thermal conductivity of the compound show large hysteresis below the metal–insulator transition. The large value of the effective mass (m*~8m{sub e}) in the metallic state indicates the narrow character of the 3d band. The electric conduction at low temperatures (T=2–20 K) is governed by the variable range hopping of the charge carriers.

  7. Electronic properties and the nature of metal-insulator transition in NdNiO3 prepared at ambient oxygen pressure

    Science.gov (United States)

    Hooda, M. K.; Yadav, C. S.

    2016-06-01

    We report the electronic properties of the NdNiO3, prepared at the ambient oxygen pressure condition. The metal-insulator transition temperature is observed at 192 K, but the low temperature state is found to be less insulating compared to the NdNiO3 prepared at high oxygen pressure. The electric resistivity, Seebeck coefficient and thermal conductivity of the compound show large hysteresis below the metal-insulator transition. The large value of the effective mass (m*~8me) in the metallic state indicates the narrow character of the 3d band. The electric conduction at low temperatures (T=2-20 K) is governed by the variable range hopping of the charge carriers.

  8. Structured Pd/γ-Al2O3 Prepared by Washcoated Deposition on a Ceramic Honeycomb for Compressed Natural Gas Applications

    Directory of Open Access Journals (Sweden)

    Małgorzata Adamowska

    2015-01-01

    Full Text Available The preparation of a coating procedure was studied, from the washcoating with γ-alumina to the deposition of palladium by excess solvent or incipient wetness impregnation. The powder and the washcoat layers were studied by different characterisation techniques such as SEM, BET surface area, and XRD. Vibration-resistance and heat-resistance were also evaluated. It was shown that the alumina layer is quite well deposited on the channel walls (SEM images. However, a detachment of the washcoat layer was observed after ultrasound treatment. It was proved that the monolith Pd impregnation method by incipient wetness impregnation is more efficient. The presence of palladium was confirmed using HRTEM, the palladium was present under the Pd (II oxidation state, and the size of PdO particles varies between 2.5 and 3.1 nm. The catalytic properties of the monolith catalyst were carried out using temperature programmed surface reaction (TPSR. The efficiency of the procedure of the monolith catalyst preparation was confirmed by comparing the activity of the prepared catalyst with the one of a model catalyst.

  9. Preparation and response to radiation and nuclear emergencies in case of natural disasters; Preparacion y respuesta a emergencias nucleares y radiologicas en caso de desastres naturales

    Energy Technology Data Exchange (ETDEWEB)

    Vegueria, Pablo Jerez, E-mail: pablo@orasen.co.cu [Centro Nacional de Seguridad Nuclear (CNSN), La Habana (Cuba); Lafortune, J.F., E-mail: padijeff@gmail.com [VP International Affairs, International Safety Research (Canada)

    2013-07-01

    The impact of natural disasters in cities and communities has grown by different causes in different parts of the world. There are several examples of the impact that have caused extreme natural events in facilities and activities in which ionizing radiation are used. The recent example of the accident at the nuclear power plant of Fukushima Daichi with release of radioactive substances to the environment caused by an earthquake and a tsunami show the need of the increasing improvement in the safety of facilities and activities that use ionizing radiation and radioactive materials in general. Planning and response to events of this nature is another aspect that is important and needs attention. The IAEA documents offer a comprehensive and effective guide to achieve an appropriate degree of readiness to respond to nuclear and radiological emergencies in any situation. However, there are specific challenges for planning and response posed a radiological emergency caused by an extreme natural event or occurring simultaneously with this. The present work deals with essential aspects to take into account by the authorities who coordinate the planning and response to radiological emergencies to deal with extreme natural events.

  10. Synthesis of naphthalene-naphthol-benzaldehyde pitch resin%萘-萘酚-苯甲醛沥青树脂的合成研究

    Institute of Scientific and Technical Information of China (English)

    周广明; 赖仕全; 岳莉; 赵雪飞; 李小侠; 王荣荣

    2012-01-01

    Naphthalene -naphtho]-berzaldlehyde three components pitch resin has been synthesized by cationic polymerization in the presence of concentrated sulfuric acid, in which the naphtho] molecule was introduced lo the molecular chains of naphthalene -benzaldehyde two components pitch resin. The structure of the pitch resin obtained was characterized by Fourier transform infrared spectnoscopy (VI - IR). The effects of synthesis conditions on the properties of the pitch resin such as softening point, coking value and bond strength were investigated by single factor experiments. Experimental results showed that the suitable technology conditions of synthesizing the naphthalene-naphthol-benzaldehyde pilch resin were: the amount of subatance ratio of naphthalene, naphthol and benzaldehyde 0.67*0.33:1, the reaction temperature 160 ℃, the reaction time 300 min and the usage of catalyst 10%. Under the optimal conditions, the pitch resin exhibits the softening point of 87,5 ℃, coking value of 32.1% and the bond strength of 41.1. The naphthalene - naphthol - benzaldehyde three components pilch resin with different bond properties can be obtained by controlling the substance amount of naphthol in reaction system.%在浓硫酸的催化作用下,采用阳离子聚合法在萘-苯甲醛二元组分沥青树脂分子链上引入了萘酚分子,合成了萘-萘酚-苯甲醛三元组分沥青树脂.用FT-IR光谱仪表征了合成树脂的结构.通过单因素实验,考察了合成条件对沥青树脂软化点、结焦值和黏结强度等黏结性能的影响规律.实验结果表明,合成萘-萘酚-苯甲醛沥青树脂适宜的工艺条件:萘、萘酚和苯甲醛的物质的量比为0.67:0.33:1,反应温度为160℃,反应时间为300 min,催化剂用量为10%.在此条件下,合成沥青树脂的软化点为87.5℃,结焦值为32.1%,黏结强度为41.1.改变反应体系中萘酚的物质的量,能获得具有不同黏结性能的萘-萘酚-苯甲醛三元组分沥青树脂.

  11. Densities and volumetric properties of binary mixtures of the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate with benzaldehyde at T = (298.15 to 313.15) K

    Energy Technology Data Exchange (ETDEWEB)

    Gao Haiyan; Qi Feng [School of Chemical and Material Engineering, Jiangnan University, Road of Lihu, Wuxi, Jiangsu 214122 (China); Wang Haijun [School of Chemical and Material Engineering, Jiangnan University, Road of Lihu, Wuxi, Jiangsu 214122 (China)], E-mail: wanghj329@hotmail.com

    2009-07-15

    The densities of the binary mixtures formed by 1-butyl-3-methylimidazolium tetrafluoroborate [bmim][BF{sub 4}] with aromatic compound (benzaldehyde) have been determined over the full range of compositions at the temperature range from (298.15 to 313.15) K and at atmospheric pressure using a vibrating-tube densimeter (DMA4500). Excess molar volumes (V{sub m}{sup E}) have been obtained from these experimental results, and been fitted by the fourth-order Redlich-Kister equation. In addition, partial molar volumes, apparent molar volumes, and partial molar volumes at infinite dilution have been calculated for each component. Our results show V{sub m}{sup E} decreases slightly when temperature increases in the systems studied. The results have been interpreted in terms of ion-dipole interactions and structural factors of the ionic liquid and these organic molecular liquids.

  12. Synthesis, Physical Characterization of M(III Transition Metal Complexes Derived from Thiodihydrazide and 5-tert-Butyl-2-hydroxy-3-(3-phenylpent-3-yl Benzaldehyde

    Directory of Open Access Journals (Sweden)

    Gajendra Kumar

    2012-01-01

    Full Text Available A Schiff base ligand was synthesized by reacting 5-tert-butl-2-hydroxy-3-(3-phenylpent-3-yl benzaldehyde and thiodihydrazide (2:1 and a series of metal complexes with this new ligand were synthesized by reaction with Cr (III, Mn (III, and Fe (III metal salt in methanolic medium. The Schiff base ligand and its complexes have been characterized with the help of elemental analysis, conductance measurements, magnetic measurements and their structure configuration have been determined by various spectroscopic (electronic, IR, 1H NMR, 13C NMR, GCMS techniques. Electronic and magnetic moments of the complexes indicate that the geometries of the metal centers were octahedral. IR spectral data suggest that ligand behaves as a tetradentate ligand with ONNO donor sequence towards the metal ion.

  13. Inner-shell spectroscopy of benzaldehyde, terephthalaldehyde, ethyl benzoate, terephthaloyl chloride, and phosgene: Models for core excitation of poly(ethylene terephthalate)

    Energy Technology Data Exchange (ETDEWEB)

    Hitchcock, A.P.; Urquhart, S.G. [McMaster Univ., Ontario (Canada); Rightor, E.G. [Texas Polymer Centre, Freeport, TX (United States)

    1992-10-29

    Oscillator strengths for C 1s and O 1s excitation of terephthalaldehyde, benzaldehyde, and ethyl benzoate and C 1s, O 1s and Cl 2p excitation of terephthaloyl chloride and phosgene have been derived from electron energy loss spectra recorded under scattering conditions where electric dipole transitions dominate. Extended Hueckel molecular orbital (EHMO) calculations were used to aid interpretation of the core excitation spectra of these multifunctional organic molecules. The experimental molecular spectra and EHMO calculations were used to estimate the C 1s and O 1s core excitation spectra of poly(ethylene terephthalate) (PET). Comparisons to the C 1s and O 1s energy loss spectra of PET recorded in an electron microscope have demonstrated that gas-phase spectra and theoretical studies of molecular analogues are useful in interpreting the core excitation spectra of polymers. 48 refs., 14 figs., 13 tabs.

  14. Active-Site Engineering of Benzaldehyde Lyase Shows That a Point Mutation Can Confer Both New Reactivity and Susceptibility to Mechanism-Based Inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, Gabriel S.; Kneen, Malea M.; Petsko, Gregory A.; Ringe, Dagmar; McLeish, Michael J. (Brandeis); (IUPUI)

    2010-02-11

    Benzaldehyde lyase (BAL) from Pseudomonas putida is a thiamin diphosphate (ThDP)-dependent enzyme that catalyzes the breakdown of (R)-benzoin. Here we report that a point mutant, BAL A28S, not only catalyzes the decarboxylation of benzoylformate but, like benzoylformate decarboxylase (BFDC), is also inactivated by the benzoylformate analogues methyl benzoylphosphonate (MBP) and benzoylphosphonate (BP). The latter has no effect on wild-type BAL, and the inactivation of the A28S variant is shown to result from phosphorylation of the newly introduced serine residue. This lends support to the proposal that an appropriately placed nucleophile facilitates the expulsion of carbon dioxide from the active site in many ThDP-dependent decarboxylases.

  15. A closed concept of extractive whole cell microbial transformation of benzaldehyde into L-phenylacetylcarbinol by Saccharomyces cerevisiae in novel polyethylene-glycol-induced cloud-point system.

    Science.gov (United States)

    Wang, Zhilong; Liang, Rui; Xu, Jian-He; Liu, Yubo; Qi, Hanshi

    2010-03-01

    Extractive microbial transformation of benzaldehyde into L-phenylacetylcarbinol (L-PAC) by Saccharomyces cerevisiae (Baker's yeast) has been carried out in a novel polyethylene-glycol-induced cloud-point system (PEG-CPS). The extractive microbial transformation in the PEG-CPS and a downstream process for stripping of the product from the microbial transformation broth with microemulsion extraction are demonstrated. The results indicate that the PEG-CPS maintains the advantage of CPS for in situ extraction of polar product in the microbial transformation. At the same time, the utilization of hydrophilic nonionic surfactant in the PEG-CPS is favorable for stripping of product from the nonionic surfactant in the microbial transformation broth by Winsor I microemulsion extraction. Thus, a closed concept of in situ extraction of polar product in microbial transformation and its downstream process of product recovery are fulfilled at the same time.

  16. A Helical Polyphenylacetylene Having Amino Alcohol Moieties Without Chiral Side Groups as a Chiral Ligand for the Asymmetric Addition of Diethylzinc to Benzaldehyde.

    Science.gov (United States)

    Liu, Lijia; Long, Qing; Aoki, Toshiki; Zhang, Geng; Kaneko, Takashi; Teraguchi, Masahiro; Zhang, Chunhong; Wang, Yudan

    2015-08-01

    One-handed helical polyphenylacetylenes having achiral amino alcohol moieties, but no chiral side groups, were synthesized by the helix-sense-selective copolymerization of an achiral phenylacetylene having an amino alcohol side group with a phenylacetylene having two hydroxyl groups. Since the resulting helical copolymers were successfully utilized as chiral ligands for the enantioselective alkylation of benzaldehyde with diethylzinc, we can conclude that the main-chain chirality based on the one-handed helical conformation is useful for the chiral catalysis of an asymmetric reaction for the first time. The enantioselectivities of the reaction were controlled by the optical purities of the helical polymer ligands. In addition, the polymer ligands could be easily recovered by precipitation after the reaction.

  17. System appraisal of decentralized utilization of biogas versus feed into natural gas networks. An evaluation of methods for biogas preparation and feeding; Systemvergleich dezentrale Biogasnutzung versus Biogaseinspeisung in Erdgasnetze. Eine Bewertung von Verfahren zur Biogasaufbereitung und Einspeisung

    Energy Technology Data Exchange (ETDEWEB)

    Heinen, Joerg; Stichtenoth, Jan [RWE Energy AG, Dortmund (Germany); Erich, Egon [IUTA e.V., Duisburg (Germany)

    2008-11-15

    Feeding of biogas into natural gas distribution networks is an option for expanding the use of regenerable energy sources. In view of the still experimental character of biogas preparation, in particular, a concluding evaluation on energy and process-engineering criteria remains to be submitted. This article describes the various methods of biogas preparation using process-engineering simulations. The mass-flows and energy-flows and methane losses in the individual processes are examined and the specific advantages and disadvantages of the various procedures derived. The article concludes with a comparative assessment of biogas feeding and decentralized biogas-fueled power generation on the basis of an efficiency and cost model. (orig.)

  18. Structural, spectral, electrochemistry, thermal properties and theoretical studies on 4-[N, N-di(4-tolyl)amino] benzaldehyde-2-chloro benzoylhydrazone

    Science.gov (United States)

    Lizeng, Liu; Wei, Li; Xianfang, Meng; Dongzhi, Liu; Gongfeng, Xu; Zhengchen, Bai

    2014-11-01

    The title compound 4-[N, N-di(4-tolyl)amino] benzaldehyde-2-chloro benzoylhydrazone (C28H24ClN3O, Mr = 453.96) was synthesized by the reaction of 4-[N, N-di(4-tolyl)amino] benzaldehyde with 2-chlorobenzohydrazide, and its structure was characterized by IR, 1H NMR, 13H NMR, high-resolution mass spectrometry and single-crystal X-ray diffraction. The crystal belongs to Monoclinic, space group P2(1)/n with a = 12.626(3), b = 12.609(3), c = 15.837(3) Å, β = 90.00(3)°, Z = 5, V = 2512.5(9) Å3, Mr = 453.95, Dc = 1.280 g/cm3, μ = 0.183 mm-1, F(0 0 0) = 1024, R = 0.0432 and wR = 0.1087. X-ray analysis revealed that one of the benzene ring and acylhydrazone were essentially planar, the 2-chloro benzene ring and amide were non-planar, the torsion angles C(1)sbnd C(6)sbnd C(7)sbnd O(1) and C(5)sbnd C(6)sbnd C(7)sbnd O(1) are 61.4(5)° and -114.4(4)°. The thermal stability studies indicate that the title compound is stable up to 341.1 °C. The spectral, electrochemistry properties and theoretical studies show that the title compound is a good candidate for the charge-transporting materials.

  19. Nanocrystalline TiO2 preparation by microwave route and nature of anatase–rutile phase transition in nano TiO2

    Indian Academy of Sciences (India)

    G M Neelgund; S A Shivashankar; B K Chethana; P P Sahoo; K J Rao

    2011-10-01

    Nanopowders of TiO2 has been prepared using a microwave irradiation-assisted route, starting from a metalorganic precursor, bis(ethyl-3-oxo-butanoato)oxotitanium (IV), [TiO(etob)2]2. Polyvinylpyrrolidone (PVP) was used as a capping agent. The as-prepared amorphous powders crystallize into anatase phase, when calcined. At higher calcination temperature, the rutile phase is observed to form in increasing quantities as the calcination temperature is raised. The structural and physicochemical properties were measured using XRD, FT–IR, SEM, TEM and thermal analyses. The mechanisms of formation of nano-TiO2 from the metal–organic precursor and the irreversible phase transformation of nano TiO2 from anatase to rutile structure at higher temperatures have been discussed. It is suggested that a unique step of initiation of transformation takes place in Ti1/2O layers in anatase which propagates. This mechanism rationalizes several key observations associated with the anatase–rutile transformation.

  20. Preparation of Modified Magnetic Nanocomposites Dithiooxamide/Fe3O4 for Preconcentration and Determination of Trace Amounts of Cobalt Ions in Food and Natural Water Samples

    Directory of Open Access Journals (Sweden)

    Ali Mirabi

    2016-09-01

    Full Text Available The first study on the high efficiency of nanometer-sized magnetic nanoparticles (Fe3O4 coated with sodium dodecyl sulfate (SDS and dithiooxamide as a new sorbent solid phase extraction has been reported. Modified magnetic nanicomposites was used to preconcentrate and separate Co (II ions in food and environmental water samples. Magnetic nanoparticles were prepared by chemical precipitation of Fe (II and Fe (III salts from aqueous solution by ammonia solution. These magnetic nanoparticles and nanocomposites were characterized by scanning electron microscopy (SEM, transmission electron microscopy (TEM, thermo gravimetric analysis (TGA and elemental analysis CHNS. A micro sample introduction system was employed for the nebulization micro-volume of diluted solution into flame atomic absorption spectrometry (FAAS. The extraction conditions were optimized by selecting the appropriate extraction parameters including the amount of nanosorbent, pH value, volume of dithiooxamide and condition of eluting solution. The detection limit of this method for Co (II ions was 1.21 ng ml-1 and the R.S.D. was 0.9% (n=6. The advantages of this new method include rapidity, easy preparation of nanosorbents and a high preconcentration factor. The proposed method has been applied to the determination of Co (II ions at trace levels in real samples such as, kiwi, orange, cucumber, apple, green pepper, honey, potato, tap water, river water and sea water with satisfactory results.

  1. Research opportunities for bioactive natural constituents in agriculture and food prepared for the 50th anniversary of the Journal of Agricultural and Food Chemistry.

    Science.gov (United States)

    Molyneux, Russell J

    2002-11-20

    The Journal of Agricultural and Food Chemistry recently introduced a new subject matter category titled "Bioactive Constituents" to cover investigations of the composition of natural compounds and their biological activity in crops and foods. It is recognized by the Editors that a number of other journals specialize in various aspects of the chemistry of natural products, but the intent of this classification is to emphasize and stimulate submission of manuscripts in such areas of agricultural and food chemistry that have so far been neglected or under-represented. Selected topics dealing with bioactive constituents are given as representative examples of the types of investigations that would be appropriate to the scope of the Journal.

  2. On the Effect of Preparation Methods of PdCe-MOR Catalysts as NOx CH4-SCR System for Natural Gas Vehicles Application

    Directory of Open Access Journals (Sweden)

    Acácio Nobre Mendes

    2015-10-01

    Full Text Available In the present work, the effect of several parameters involved in the preparation of PdCe-HMOR catalysts active for NOx selective catalytic reduction with methane (NOx CH4-SCR was studied. Results show that the catalytic performance of Pd-HMOR is better when palladium is introduced by ion-exchange, namely at room temperature. It was also shown that Pd loading does not influence the formation of cerium species, namely surface Ce4+ (CeO2 species and CeO2 species in interaction with Pd. However, when Ce is introduced before Pd, more surface CeO2 species are stabilized in the support and less CeO2 become in interaction with Pd, which results in a worse NOx CH4-SCR catalytic performance.

  3. PREPARATION AND CHARACTERIZATION OF SOME SILICON (IV COMPLEXES

    Directory of Open Access Journals (Sweden)

    Z.F DAWOOD

    2008-06-01

    Full Text Available Silicon(IV complexes containing mixed ligands: Shiff-bases (AH {derived from 2- or 3- amino-pyridine with 2-hydroxy- or 3-me- thoxy- or 2-hydroxy-3-methoxy-benzaldehyde} and benzalde- hyde semicarbazone (BSCH, have been prepared. The resulted complexes have been characterized by elemental analysis, molar conductance values, infrared and electronic spectral data. Complexes of the type [Si(BSCH2(AH]Cl4, [Si(BSC2(AnH]Cl2 and [Si(BSC2(A]Cl (where n=2 or 3, A=deprotonated Schiff-base ligands , BSC= deprotonated semicarbazone have been proposed in neutral and basic medium, respectively.

  4. STUDY ON THE PERFORMANCE OF Co-SBA-15 CATALYST FOR CATALYTIC OXIDATION OF STYRENE TO BENZALDEHYDE%Co-SBA-15催化苯乙烯氧化制苯甲醛反应性能的研究

    Institute of Scientific and Technical Information of China (English)

    白向向; 沈健

    2011-01-01

    以Co(NO3)2·6H2O为钴源制备Co-SBA-15介孔分子筛,并用XRD、BET方法对Co-SBA-15结构进行表征.结果表明,负载钴的SBA-15具有介孔分子筛的结构特征.以质量分数为30%的H2O2为氧化剂,丙酮为溶剂,对Co-SBA-15催化氧化苯乙烯反应进行研究.在苯乙烯用量5 mL、n(H2O2)∶n(苯乙烯)=2、催化剂焙烧温度500℃、Co(15 %)-SBA-15用量100mg、丙酮用量10mL、反应温度100℃、反应时间4h的条件下,苯乙烯转化率为99.12%,苯甲醛选择性为77.62%,苯甲醛收率为76.94%.%Cobalt-containing mesoporous molecular sieves Co-SBA-15 were prepared using Co(NO3) · 6H2O as cobalt source and the obtained molecular sieves were characterized by XRD and BET. Test results showed that Co-SBA-15 possessed the characteristic structural features of mesoporous molecular sieve. The performance of Co-SBA-15 for catalytic oxidation of styrene was investigated using 30% H2O2 as oxidant and acetone as solvent. Under the conditions of using 5 mL of styrene, 10 mL of acetone, 100 mg Co(15%)-SBA-15 catalyst calcined at 500 ℃ ,H2O2/styrene molar ratio of 2,a reaction temperature of 100 ℃ and a reaction time of 4 h,the conversion of styrene reached 99. 12% ,the selectivity and yield of benzaldehyde was 77. 62% and 76. 94% ,respectively.

  5. Synthesis of grafted natural pozzolan with 3-aminopropyltriethoxysilane: preparation, characterization, and application for removal of Brilliant Green 1 and Reactive Black 5 from aqueous solutions.

    Science.gov (United States)

    Wamba, Alfred G N; Lima, Eder C; Ndi, Sylvere K; Thue, Pascal S; Kayem, Joseph G; Rodembusch, Fabiano S; Dos Reis, Glaydson S; de Alencar, Wagner S

    2017-08-03

    Natural pozzolan is an amorphous silicate-based material of volcanic origin. In this work, the natural pozzolan was modified by using 3-aminopropyltriethoxysilane (APTES) as a grafting agent. This material was characterized by pHpzc, N2 adsorption/desorption curves, FTIR, TGA/DTG, DRUV, SEM, and elementary analysis. The functionalized materials were used for the removal of Reactive Black 5 (RB-5) and Brilliant Green 1 (BG-1) dyes from aqueous solutions using batch-contact adsorption. The characterization of modified pozzolan by FTIR, TGA/DTG, BET, and DRUV-vis revealed the effectiveness of grafting of amine functional group on pozzolan structure. The kinetic adsorption data were better fitted with general order for both dyes while for equilibrium models were better fitted by the Liu isotherm model. The maximum sorption capacities Q max (at 50 °C) obtained with the modified pozzolan were 350.6 and 300.9 mg g(-1) for BG-1 and RB-5, at pH 9.0 and 2.0, respectively. The thermodynamic parameters show that the removal of dyes was spontaneous and endothermic. The modified material was also tested for the treatment of simulated dye house effluents showing very high efficiency.

  6. Cytotoxic conjugates of betulinic acid and substituted triazoles prepared by Huisgen Cycloaddition from 30-azidoderivatives

    Science.gov (United States)

    Sidova, Veronika; Zoufaly, Pavel; Pokorny, Jan; Dzubak, Petr; Hajduch, Marian; Popa, Igor

    2017-01-01

    In this work, we describe synthesis of conjugates of betulinic acid with substituted triazoles prepared via Huisgen 1,3-cycloaddition. All compounds contain free 28-COOH group. Allylic bromination of protected betulinic acid by NBS gave corresponding 30-bromoderivatives, their substitution with sodium azides produced 30-azidoderivatives and these azides were subjected to CuI catalysed Huisgen 1,3-cycloaddition to give the final conjugates. Reactions had moderate to high yields. All new compounds were tested for their in vitro cytotoxic activities on eight cancer and two non-cancer cell lines. The most active compounds were conjugates of 3β-O-acetylbetulinic acid and among them, conjugate with triazole substituted by benzaldehyde 9b was the best with IC50 of 3.3 μM and therapeutic index of 9.1. Five compounds in this study had IC50 below 10 μM and inhibited DNA and RNA synthesis and caused block in G0/G1 cell cycle phase which is highly similar to actinomycin D. It is unusual that here prepared 3β-O-acetates were more active than compounds with the free 3-OH group and this suggests that this set may have common mechanism of action that is different from the mechanism of action of previously known 3β-O-acetoxybetulinic acid derivatives. Benzaldehyde type conjugate 9b is the best candidate for further drug development. PMID:28158265

  7. Preparation, characterization and catalytic properties of MCM-48 supported tungstophosphoric acid mesoporous materials for green synthesis of benzoic acid

    Science.gov (United States)

    Wu, Hai-Yan; Zhang, Xiao-Li; Chen, Xi; Chen, Ya; Zheng, Xiu-Cheng

    2014-03-01

    MCM-48 and tungstophosphoric acid (HPW) were prepared and applied for the synthesis of HPW/MCM-48 mesoporous materials. The characterization results showed that HPW/MCM-48 obtained retained the typical mesopore structure of MCM-48, and the textural parameters decreased with the increase loading of HPW. The catalytic oxidation results of benzyl alcohol and benzaldehyde with 30% H2O2 indicated that HPW/MCM-48 was an efficient catalyst for the green synthesis of benzoic acid. Furthermore, 35 wt% HPW/MCM-48 sample showed the highest activity under the reaction conditions.

  8. 不同制备方法对凹凸棒石/天然橡胶复合材料性能的影响%Influence of Different Preparation Methods on The Properties of Attapulgite/natural Rubber Composites

    Institute of Scientific and Technical Information of China (English)

    胡盛; 杨眉; 田大听; 周红艳; 胡卫兵; 谭远斌; 曹贞虎

    2011-01-01

    Attapulgite/natural rubber composites(M-ANRC) and modified attapulgite/natural rubber composites(M-MANRC) were prepared by mechanical blending. Attapulgite/natural rubber composites (C-ANRC) and modified attapulgite/natural rubber composites(C-MANRC) were prepared by co-coagulating rubber latex and clay aqueous suspension. The mechanical properties suggested that C-ANRC prepared by co-coagulating rubber latex and clay aqueous suspension were better than M-ANRC. The tensile strength, tear strength and tensile modulus at 200% of the C-ANRC increased by 77.5 %, 35.9 %, 125.6%, respectively. The mechanical properties of the C-MANRC prepared by co-coagulating rubber latex and clay aqueous suspension was the best. The structure of the C-ANRC, C-MANRC shown by scanning electron microscope (SEM) is tight.Attapulgite inserted into natural rubber matrix in C-ANRC and C-MANRC more uniformly dispersive than in M-ANRC is basically composed of nano-rods. Attapulgite combines well with natural rubber matrix. The process of co-coagulating rubber latex and clay aqueous suspension was analyzed.%采用机械共混法制备了凹凸棒石/天然橡胶复合材料(M-ANRC)和改性凹凸棒石/天然橡胶复合材料(M-MANRC),采用乳液共混共凝法制备了凹凸棒石/天然橡胶复合材料(C-ANRC)和改性凹凸棒石/天然橡胶复合材料(C-MANRC).力学性能测试结果表明,与M-ANRC的力学性能相比,C-ANRC的扯断强度、撕裂强度、200%定伸强度分别提高了77.5%、35.9%、125.6%; C-MANRC的综合力学性能最好.SEM分析结果显示,C-ANRC和C-MANRC中的凹凸棒石比M-ANRC和M-MANRC中的凹凸棒石在天然橡胶基体中分散得更加均匀且棒径更小;C-MANRC结构致密,凹凸棒石基本上都呈纳米棒状,且较均匀地分布在天然橡胶基体中,与天然橡胶基体结合良好.同时,对乳液共混共凝过程进行了初步分析.

  9. DC Electrical Conductivity Retention, Optical Properties and Ammonia Sensing Analysis of Naturally Degraded CSA-Doped Graphene/polyaniline Composite Nanofibers Prepared with CTAB

    Science.gov (United States)

    Ghazali, Sayyed; Hossain, Muhammad M.; Khan, Abuzar; Khan, Mohd Y.; Hasan, Mudassir

    2016-09-01

    In this paper, we report surfactant-mediated synthesis of camphor sulfonic acid (CSA)-doped polyaniline/graphene (PANI/GN) composite nanofibers as an electrical conductor and excellent ammonia sensor. The synthesis was mediated by cetyltrimethylammonium bromide as surfactant. The as-synthesized composite nanofibers were characterized by Raman spectroscopy, scanning electron microscopy, tunneling electron microscopy, x-ray diffraction, diffused reflectance spectroscopy and differential scanning calorimetry. The electrical conductivity of the CSA-doped PANI/GN composite nanofibers was found to be remarkably enhanced as compared to the CSA-doped PANI. The boost in electronic conductivity could be attributed to an improved electronic interaction between CSA-doped PANI backbone and GN present in the composite system. The naturally degraded CSA-doped PANI/GN composite nanofibers showed a decrease in electrical conductivity but worked as a good ammonia sensor in open atmospheric conditions.

  10. Effect of electrolytes nature and concentration on the morphology and structure of MoS{sub 2} nanomaterials prepared using one-pot solvothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Akram, H., E-mail: akramhanane@yahoo.fr [Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, Cantoblanco, 28049 Madrid (Spain); Laboratoire de Génie Chimique et Valorisation des Ressources, Faculté des Sciences et Techniques de Tanger, Université Abdelmalek Essâadi, B.P. 416 Tangier (Morocco); Mateos-Pedrero, C., E-mail: cmpedrero@yahoo.es [Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculdade de Engenharia da Universidade do Porto Rua Roberto Frias, s/n4200-465, Porto (Portugal); Gallegos-Suárez, E.; Guerrero-Ruíz, A. [Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, Cantoblanco, 28049 Madrid (Spain); Grupo de Diseño y Aplicación de Catalizadores Heterogéneos, Unidad Asociada UNED—ICP (CSIC), Madrid (Spain); Chafik, T. [Laboratoire de Génie Chimique et Valorisation des Ressources, Faculté des Sciences et Techniques de Tanger, Université Abdelmalek Essâadi, B.P. 416 Tangier (Morocco); Rodríguez-Ramos, I. [Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, Cantoblanco, 28049 Madrid (Spain); Grupo de Diseño y Aplicación de Catalizadores Heterogéneos, Unidad Asociada UNED—ICP (CSIC), Madrid (Spain)

    2014-07-01

    Different MoS{sub 2} nanostructures have been obtained following an innovative one-step solvothermal method by changing the concentration and type of the electrolyte while avoiding the use of surfactant. It was found that the chemical nature of the studied electrolyte ((NH{sub 4}){sub 2}CO{sub 3} or KCl) do not significantly affect the morphology and structure of the obtained MoS{sub 2} nanomaterials. Nevertheless, increasing the electrolyte concentration yields to a remarkable modification of the morphology of the resulting MoS{sub 2} from nanospheres to worm-shaped then finally to nanotubes. All the obtained nanomaterials were characterized by X-ray diffraction, (XRD), transmission electron microscopy (TEM, HRTEM), Fourier transformation infra-red spectroscopy (FTIR), thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS).

  11. Preparation and characterization of chelating fibers based on natural wool for removal of Hg(II), Cu(II) and Co(II) metal ions from aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Monier, M., E-mail: monierchem@yahoo.com [Chemistry Department, Faculty of Science, Mansoura University, 35516 (Egypt); Nawar, N., E-mail: nnawar@mans.edu.eg [Chemistry Department, Faculty of Science, Mansoura University, 35516 (Egypt); Abdel-Latif, D.A. [Chemistry Department, Faculty of Science, Mansoura University, 35516 (Egypt)

    2010-12-15

    The graft copolymerization of acrylonitrile (AN) onto natural wool fibers initiated by KMnO{sub 4} and oxalic acid combined redox initiator system in limited aqueous medium was carried out in heterogeneous media. Moreover, modification of the grafted wool fibers was done by changing the nitrile group (-CN) into cyano-acetic acid {alpha}-amino-acrylic-hydrazide through the reaction with hydrazine hydrate followed by ethylcyanoacetate which eventually produce wool-grafted-poly(cyano-acetic acid {alpha}-amino-acrylic-hydrazide) (wool-g-PCAH) chelating fibers. The application of the modified fibers for metal ion uptake was studied using Hg{sup 2+}, Cu{sup 2+} and Co{sup 2+}. The modified chelating fibers were characterized using FTIR spectroscopy, SEM and X-ray diffraction.

  12. DC Electrical Conductivity Retention, Optical Properties and Ammonia Sensing Analysis of Naturally Degraded CSA-Doped Graphene/polyaniline Composite Nanofibers Prepared with CTAB

    Science.gov (United States)

    Ghazali, Sayyed; Hossain, Muhammad M.; Khan, Abuzar; Khan, Mohd Y.; Hasan, Mudassir

    2017-01-01

    In this paper, we report surfactant-mediated synthesis of camphor sulfonic acid (CSA)-doped polyaniline/graphene (PANI/GN) composite nanofibers as an electrical conductor and excellent ammonia sensor. The synthesis was mediated by cetyltrimethylammonium bromide as surfactant. The as-synthesized composite nanofibers were characterized by Raman spectroscopy, scanning electron microscopy, tunneling electron microscopy, x-ray diffraction, diffused reflectance spectroscopy and differential scanning calorimetry. The electrical conductivity of the CSA-doped PANI/GN composite nanofibers was found to be remarkably enhanced as compared to the CSA-doped PANI. The boost in electronic conductivity could be attributed to an improved electronic interaction between CSA-doped PANI backbone and GN present in the composite system. The naturally degraded CSA-doped PANI/GN composite nanofibers showed a decrease in electrical conductivity but worked as a good ammonia sensor in open atmospheric conditions.

  13. Synthesis of Graft Copolymer of Natural Rubber by ATRP Ⅲ.Preparation of NR-g-PMMA%采用ATRP合成天然橡胶接枝共聚物——Ⅲ.NR-g-PMMA的制备

    Institute of Scientific and Technical Information of China (English)

    赵伟; 廖建和; 廖禄生; 杨耀华; 黄仙红; 陈永平

    2012-01-01

    An atom transfer radical polymerization(ATRP) macroinitiator, bromo-(natural rubber) [NR-Br(l) ], was synthesized by the reaction of natural rubber (NR) with N-bromosuccinimide. A novel graft copolymer, (natural rubber)-g-poly( methyl methacrylate) [NR-g-PMMA(2) ] , was prepared from methyl methacrylate (MMA) using 1 as a macroinitiator and CuBr/PMDTA as the catalyst by ATRP. The structures were characterized by !H NMR and IR. The results of preliminary study of graft copolymerization dynamics showed that the reaction of NR with NBS at high temperature easily occurred addition and cyclization, 1 prepared at room temperature exhibited higher initiating activity, and the graft copolymerization accorded with first-order kinetic reaction because the molecular weight of 2 increaseed as MMA monomer conversion increases.%N-溴代丁二酰亚胺与天然橡胶(NR)反应合成了大分子引发剂——溴代天然橡胶[NR-Br(1)].通过原子转移自由基聚合(ATRP),以CuBr/PMDTA为催化体系,1引发甲基丙烯酸甲酯(MMA)接枝共聚制得新型天然橡胶-g-聚甲基丙烯酸甲酯[NR-g-PMMA(2)],其结构经1H NMR和IR表征.初步聚合反应动力学研究结果表明,NBS与NR在高温下反应容易伴随双键加成和环化反应,于室温反应所得1具有较高的引发活性;接枝聚合符合一级动力学反应,即2的分子量随MMA单体转化率的提高而增加.

  14. Trial end points and natural history in patients with G11778A Leber hereditary optic neuropathy : preparation for gene therapy clinical trial.

    Science.gov (United States)

    Lam, Byron L; Feuer, William J; Schiffman, Joyce C; Porciatti, Vittorio; Vandenbroucke, Ruth; Rosa, Potyra R; Gregori, Giovanni; Guy, John

    2014-04-01

    IMPORTANCE Establishing the natural history of G11778A Leber hereditary optic neuropathy (LHON) is important to determine the optimal end points to assess the safety and efficacy of a planned gene therapy trial. OBJECTIVE To use the results of the present natural history study of patients with G11778A LHON to plan a gene therapy clinical trial that will use allotopic expression by delivering a normal nuclear-encoded ND4 gene into the nuclei of retinal ganglion cells via an adeno-associated virus vector injected into the vitreous. DESIGN, SETTING, AND PARTICIPANTS A prospective observational study initiated in 2008 was conducted in primary and referral institutional practice settings. Participants included 44 individuals with G11778A LHON, recruited between September 2008 and March 2012, who were evaluated every 6 months and returned for 1 or more follow-up visits (6-36 months) as of August 2012. EXPOSURES Complete neuro-ophthalmic examination and main measures. MAIN OUTCOMES AND MEASURES Visual acuity, automated visual field testing, pattern electroretinogram, and spectral-domain optical coherence tomography. RESULTS Clinical measures were stable during the follow-up period, and visual acuity was as good as or better than the other visual factors used for monitoring patients. Based on a criterion of 15 or more letters from the Early Treatment Diabetic Retinopathy Study chart, 13 eyes of 8 patients (18%) improved, but 24 months after the onset of symptoms, any further improvements were to no better than 20/100. Acuity recovery occurred in some patients despite continued marked retinal nerve fiber layer thinning indistinguishable from that in patients who did not recover visual acuity. CONCLUSIONS AND RELEVANCE Spontaneous improvement of visual acuity in patients with G11778A LHON is not common and is partial and limited when it occurs, so improvements in vision with adeno-associated virus-mediated gene therapy of a synthetic wild-type ND4 subunit gene should be

  15. Removal of nickel(II) ions from aqueous solutions using the natural clinoptilolite and preparation of nano-NiO on the exhausted clinoptilolite

    Science.gov (United States)

    Rajic, Nevenka; Stojakovic, Djordje; Jovanovic, Mina; Logar, Natasa Zabukovec; Mazaj, Matjaz; Kaucic, Venceslav

    2010-12-01

    The natural zeolite tuff (clinoptilolite) from a Serbian deposit has been studied as adsorbent for Ni(II) ions from aqueous solutions. Its sorption capacity at 298 K varies from 1.9 mg Ni g -1 (for the initial solution concentration of 100 mg Ni dm -3) to 3.8 mg Ni g -1 (for C0 = 600 mg Ni dm -3) and it increases 3 times at 338 K. The sorption is best described by the Sips isotherm model. The sorption kinetics follows the pseudo-second-order model, the activation energies being 7.44, 5.86, 6.62 and 6.63 kJ mol -1 for C0 = 100, 200, 300 and 400 mg Ni dm -3, respectively. The sorption involves a film diffusion, an intra-particle diffusion, and a chemical cation-exchange between the Na + ions of clinoptilolite and the Ni 2+ ions. The sorption is endothermic (Δ H° being 37.9, 33.4, 30.0, 27.7 and 24.3 kJ mol -1 for C0 = 100, 200, 300, 400 and 600 mg Ni dm -3, respectively) and spontaneous in the 298-338 K temperature range. Thermal treatment of the Ni(II)-loaded clinoptilolite results in the formation of spherical nano-NiO particles of approx. 5 nm in diameter which are randomly dispersed in the clinoptilolite lattice.

  16. Preparation, characterization and application of superparamagnetic iron oxide nanoparticles modified with natural polymers for removal of {sup 60}Co-radionuclides from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Sharaf El-Deen, Gehan E. [Atomic Energy Authority, Cairo (Egypt). Radioactive Waste Management Dept.; Imam, Neama G. [Atomic Energy Authority, Cairo (Egypt). Experimental Physics Dept.; Elettra, Sincrotrone, Trieste (Italy); Ayoub, Refaat R. [Atomic Energy Authority, Cairo (Egypt). Nuclear Chemistry Dept.

    2017-04-01

    Superparamagnetic iron oxide nanoparticles (IO-MNPs) coated with natural polymers, starch (IO-S MNPs) and dextrin (IO-D MNPs), were synthesized by modified co-precipitation method. IO and hybrid-IO-MNPs were characterized by XRD, SEM, HRTEM, FT-IR spectroscopy, vibrating sample magnetometer (VSM) and zeta potential (ZP). IO-S MNPs and IO-D MNPs have IO core-shell structure with core of 10.8 nm and 13.8 nm and shell of 7.5 nm and 5.9 nm, respectively. The efficiency of the hybrid IO-MNPs for sorption of {sup 60}Co(II)-radionuclides from aqueous solution was investigated under varying experimental conditions. Kinetic data were described well by pseudo-second-order mode, sorption isotherms were fitted quite with Freundlich model with maximum adsorption capacity 36.89 (mmol.g{sup -1})/(L.mmol{sup -1}){sup n} for IO-S MNPs and 24.9 (mmol.g{sup -1})/(L.mmol{sup -1}){sup n} for IO-D MNPs. Sorption of {sup 60}Co-radionuclides by IO-S MNPs was suppressed with salinity and most of the adsorbed {sup 60}Co onto IO-S MNPs could be remove with 0.1 M HCl solution. IO-S MNPs exhibits superparamagnetic properties, easier separation according to higher saturation magnetization (47 emu/g) and better adsorption for {sup 60}CO-radionuclides than IO-D MNPs.

  17. Design and Stereoselective Preparation of a New Class of Chiral Olefin Metathesis Catalysts and Application to Enantioselective Synthesis of Quebrachamine: Catalyst Development Inspired by Natural Product Synthesis

    Science.gov (United States)

    Sattely, Elizabeth S.; Meek, Simon J.; Malcolmson, Steven J.; Schrock, Richard R.; Hoveyda, Amir H.

    2010-01-01

    A total synthesis of the Aspidosperma alkaloid quebrachamine in racemic form is first described. A key catalytic ring-closing metathesis of an achiral triene is used to establish the all-carbon quaternary stereogenic center and the tetracyclic structure of the natural product; the catalytic transformation proceeds with reasonable efficiency through the use of existing achiral Ru or Mo catalysts. Ru- or Mo-based chiral olefin metathesis catalysts have proven to be inefficient and entirely nonselective in cases where the desired product is observed. In the present study, the synthesis route thus serves as a platform for the discovery of new olefin metathesis catalysts that allow for efficient completion of an enantioselective synthesis of quebrachamine. Accordingly, on the basis of mechanistic principles, stereogenic-at-Mo complexes bearing only monodentate ligands have been designed. The new catalysts provide significantly higher levels of activity than observed with the previously reported Ru- or Mo-based complexes. Enantiomerically enriched chiral alkylidenes are generated through diastereoselective reactions involving achiral Mo-based bispyrrolides and enantiomerically pure silyl-protected binaphthols. Such chiral catalysts initiate the key enantioselective ring-closing metathesis step in the total synthesis of quebrachamine efficiently (1 mol % loading, 22 °C, 1 h, >98% conversion, 84% yield) and with high selectivity (98:2 er, 96% ee). PMID:19113867

  18. 纯天然速溶绿茶的制备研究%Research on Preparation of Natural Instant Green Tea

    Institute of Scientific and Technical Information of China (English)

    何晓梅; 乔德亮; 黄仁术; 谷仿丽; 张珍林

    2016-01-01

    Purpose:The research aims to optimize the preparation process .Method:green tea is used as material ,tea polyphenols extractive rate as measurement index ;Single‐factor test ,orthogonal experiment ,and composite proteases are used to optimize technical parameters of instant green tea extraction .Through reducing pressure ,concentrating ,and drying optimized extracts , instant green tea was obtained ,extractive rate was measured ,and instant green tea quality was assessed .The results showed that :with twice enzymolysis method of cellulose and pectinase ,the optimized extraction conditions :material water ratio 1∶20 , pH value 4.5 ± 0.1 ,enzymatic hydrolization temperature 45 ℃ ,enzymatic hydrolization time 2.0 h ,cellulose input quantity 0.30% ,and pectinase input quantity 0.10% , tea polyphenols extraction rate was (19.652 ± 0.024 )% . Instant green tea extraction rate was (37 ± 0.410)% under the conditions .Vacuum freeze drying had the best effects among the three drying methods .%为了优化速溶绿茶的制备工艺,笔者以绿茶为原料,以茶多酚得率为衡量指标,采用单因素和正交试验优化复合酶法辅助浸提速溶绿茶的工艺参数。对最佳浸提条件下的浸提液进行减压浓缩、干燥得速溶绿茶,计算速溶绿茶得率,并对三种不同干燥条件下速溶绿茶品质进行评定。结果表明,纤维素酶‐果胶酶双酶组合条件下最优浸提工艺为茶水比1∶20,pH值4.5±0.1,酶解温度45℃,酶解时间2.0 h ,纤维素酶加入量0.30%,果胶酶加入量0.10%,茶多酚得率为(19.652±0.024)%。在此条件下制得速溶茶得率为(37±0.410)%。3种不同的干燥方法表明:真空冷冻干燥效果最好。

  19. 紫炭黑/天然橡胶共混胶性能的研究%Preparation and properties of purple carbon black/natural rubber composities

    Institute of Scientific and Technical Information of China (English)

    孙程; 赵艳芳; 廖小雪; 罗明超; 廖双泉

    2013-01-01

    采用机械共混法,探讨了紫炭黑(PCB)用量以及紫炭黑经偶联剂Si69改性后对紫炭黑/天然橡胶共混胶力学性能和热稳定性的影响,通过扫描电子显微镜(SEM)观察紫炭黑/天然橡胶共混胶的分散情况和断面形貌.结果表明,紫炭黑能提高橡胶的力学性能和热稳定性,经硅烷偶联剂Si69改性处理的紫炭黑可提高共混胶的力学性能,当Si69的用量为紫炭黑质量的8%时,胶料的力学性能最佳,其拉伸强度达到29.48 MPa.%The effects of the amount of PCB (Purple Carbon Black) and coupling agent Si69 modified PCB on PCB/NR (Nature Rubber) blended rubber's mechanical property and thermal stability were discussed with mechanical blending method. Dispersion and surface topography of the blended rubber were observed by SEM (Scanning Electron Microscope). The results showed that PCB could improve rubber's mechanical property and thermal stability; PCB modified with Si69 could improve blended rubber's mechanical property,which could reach the best tensile strength 29. 48 MPa when the mount of Si69 was 8% of PCB.

  20. Natural gas; Gas Natural

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Carlos A.; Moraes, Claudia C.D. [Eletricidade de Sao Paulo S.A. (ELETROPAULO), Sao Paulo, SP (Brazil); Fonseca, Carlos H.F. [Centrais Eletricas de Santa Catarina S.A., Florianopolis, SC (Brazil); Silva, Clecio Fabricio da; Alves, Ricardo P. [Companhia Paranaense de Energia (COPEL), Curitiba, PR (Brazil); Sposito, Edivaldo Soares; Hulle, Lutero [Espirito Santo Centrais Eletricas S.A. (ESCELSA), Vitoria, ES (Brazil); S. Martins, Icaro da [Centrais Eletricas do Norte do Brasil S.A. (ELETRONORTE), Belem, PA (Brazil); Vilhena, Joao Luiz S. de [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil); Fagundes, Zaluar Aquino [Companhia Estadual de Energia Eletrica do Estado do Rio Grande do Sul, Porto Alegre, RS (Brazil)

    1996-12-31

    An increase in the consumption of natural gas in Brazil is an expected fact in what concerns energetic planning. This work presents the existing situation in what concerns natural gas utilization in the main world economies, as well as an analysis of the participation of this fuel among the energy final consumption per sources. The Brazilian consumption of natural gas is also analysed as well as the international agreement between Brazil and Bolivia for natural gas commercialization. Some legal, institutional and political aspects related to natural gas commercialization are also discussed. Finally, several benefits to be brought by the utilization of natural gas are presented 10 refs., 3 tabs.

  1. Isolation of flavonoids from Aleurites moluccana using chitosan modified with benzaldehyde (CH-Bz) as chromatographic support.

    Science.gov (United States)

    Girardi, L G J; Morsch, M; Cechinel-Filho, V; Meyre-Silva, C; Rodrigues, C A

    2003-09-01

    This paper describes the preparation, characterization and use of a derivative of chitosan as a chromatographic sorbent. Chitosan modified with benzenic ring (CH-Bz) was used to separate two flavonoids, swertisin and 2"-O-rhamnosylswertisin, from ethyl acetate fraction of Aleurites moluccana. The results showed that CH-Bz can be used as a sorbent for the separation of flavonoid compounds. The studies showed that CH-Bz in column chromatography produces goods results, separation of the flavonoid compounds.

  2. Preparation of Pressure Sensitive Adhesives Based on Visible Light-Cured Natural Rubber Latex%可见光固化天然胶乳压敏胶的研制

    Institute of Scientific and Technical Information of China (English)

    唐盛斌; 徐志义; 廖建和; 陈永平; 廖双泉; 桂红星

    2009-01-01

    Degraded natural latex was mixed with terpene resin emulsion and other additives and then cured under the visible light initiator system to prepare oil-in-water emulsion type of pressure-sensitive adhesive (PSA). The ratio of degraded natural rubber to terpene resin emulsion,molecular weight and amounts of other additives were measured to observe their effects on the properties of PSA under a given light intensity. The results showed that the PSA with optimum properties was prepared under the following conditions: the ratio of the degraded natural latex and terpene resin emulsion was 1:1,molecular weight of the degraded natural rubber latex 19.8×10~4,the amount of initiator 1.2%,the amount of cross-linker 15%,and the amount of accelerant 0.4%. The DSC and TG/DTG showed that the PSA was improved in thermal stability after the PSA containing photo-initiator was cured by visible light. The PSA containing photo-initiator showed an increase of 5℃ in Tg,and was still available under a very low temperature.%采用可见光引发体系固化将降解天然胶乳与萜烯树脂乳液的其他助剂组合制备水乳型压敏胶,研究在一定光照强度下,降解天然胶乳与萜烯树脂乳液的不同配比,天然胶乳不同分子量,其他助剂的用量对压敏胶性能的影响.结果表明,降解天然胶乳与萜烯树脂乳液质量比为1:1、降解天然胶乳分子量为19.8×10~4、引发剂1.2%、交联剂15%、促进剂0.4%时压敏胶性能最优.DSC和TG/DTG表明含有光引发剂的压敏胶在光照后热稳定性提高,压敏胶的Tg升高了5℃,仍具有很低的使用温度.

  3. Hydrogen Production by Steam Reforming of Liquefied Natural Gas (LNG) Over Nickel-Phosphorus-Alumina Xerogel Catalyst Prepared by a Carbon-Templating Epoxide-Driven Sol-Gel Method.

    Science.gov (United States)

    Bang, Yongju; Park, Seungwon; Han, Seung Ju; Yoo, Jaekyeong; Choi, Jung Ho; Kang, Tae Hun; Lee, Jinwon; Song, In Kyu

    2016-05-01

    A nickel-phosphorus-alumina xerogel catalyst was prepared by a carbon-templating epoxide-driven sol-gel method (denoted as CNPA catalyst), and it was applied to the hydrogen production by steam reforming of liquefied natural gas (LNG). For comparison, a nickel-phosphorus-alumina xerogel catalyst was also prepared by a similar method in the absence of carbon template (denoted as NPA catalyst). The effect of carbon template addition on the physicochemical properties and catalytic activities of the catalysts in the steam reforming of LNG was investigated. Both CNPA and NPA catalysts showed excellent textural properties with well-developed mesoporous structure. However, CNPA catalyst retained a more reducible nickel aluminate phase than NPA catalyst. XRD analysis of the reduced CNPA and NPA catalysts revealed that nickel sintering on the CNPA catalyst was suppressed compared to that on the NPA catalyst. From H2-TPD and CH4-TPD measurements of the reduced CNPA and NPA catalysts, it was also revealed that CNPA catalyst with large amount of hydrogen uptake and strong hydrogen-binding sites showed larger amount of methane adsorption than NPA catalyst. In the hydrogen production by steam reforming of LNG, CNPA catalyst with large methane adsorption capacity showed a better catalytic activity than NPA catalyst.

  4. 从液化天然气中制取高纯度甲烷的工艺%Process for Preparing Highly Purified Methane from Liquefied Natural Gas

    Institute of Scientific and Technical Information of China (English)

    周涛

    2016-01-01

    高纯甲烷在工业、科研等部门有着广泛的用途,介绍了一种从液化天然气中分离高纯甲烷的方法,详细地介绍了整个装置的工艺流程,该分离装置能耗低,产品纯度高,运行稳定。其生产的高纯甲烷纯度为99.999%,已经达到了国内外同类产品的水平。%Highly purified methane has wide application in industrial and scientific researches. This pa-per introduced a process to prepare highly purified methane from liquefied natural gas. It also introduced in great details the whole preparation equipment, which is of low energy consumption, highly purified products, and stable operation. The purity of methane produced by this equipment was 99.999%, which has already reached the same level of the other products at home and abroad.

  5. 苯甲醛在光催化反应中氧化还原选择性的理论研究%Theoretical Study on the Selective Redox Mechanism of Benzaldehyde in Photo-catalyzed Reaction†

    Institute of Scientific and Technical Information of China (English)

    黄晓; 甘汉麟; 彭亮; 顾凤龙

    2016-01-01

    采用密度泛函理论方法在 M06-2X/6-311G*水平上模拟了不同反应条件下, TiO2对苯甲醛的光催化还原和氧化的反应。计算结果表明,苯甲醛的光催化还原和氧化反应均可在常温下发生;在缺氧但有乙醇存在的条件下,乙醇分子可与氧化性物质发生反应,生成醇自由基,苯甲醛主要发生光催化还原反应生成苯甲醇;在有氧气但无乙醇存在条件下,还原性的光生电子被氧气捕获,避免了苯甲醛被还原,主要发生光催化氧化反应生成苯甲酸。%The photoelectron and photohole could be generated on the surface of TiO2 under the UV irradiation. Some reactive species could be produced indirectly. The photoelectron could be trapped by oxygen leading to yield the superoxide anion radicals, while the photohole can react with the solvent molecules to generate the hydroxyl radical and alcohol radical. The substrate may be reduced by the photoelectron directly, or by alcohol radicals. And it may be oxidized by the photohole directly, or by the reactive species of hydroxyl radicals and superoxide anion radicals. The M06-2X/ 6-311G* method was employed to investigate the selective redox mechanism of benzaldehyde in solution, which was reduced or oxidized by the reactive species generated during the photo-catalyzed process in different reaction conditions. According to the computation results, the photo-redox reaction of benzaldehyde would be happened in room temperature. In oxygen-free ethanol solvent, the ethanol molecules could react with the oxidizing species to yield the alcohol radicals, while benzaldehyde could be mainly reduced to benzyl alcohol. In oxygen-rich without ethanol condition, the reductive photoelectron is trapped by oxygen to prohibit the reduction of benzaldehyde, so benzaldehyde is mainly oxidized to benzoic acid.

  6. High-Yield Preparation and Electrochemical Properties of Few-Layer MoS2 Nanosheets by Exfoliating Natural Molybdenite Powders Directly via a Coupled Ultrasonication-Milling Process

    Science.gov (United States)

    Dong, Huina; Chen, Deliang; Wang, Kai; Zhang, Rui

    2016-09-01

    Cost-effective and scalable preparation of two-dimensional (2D) molybdenum disulfide (MoS2) has been the bottleneck that limits their applications. This paper reports a novel coupled ultrasonication-milling (CUM) process to exfoliate natural molybdenite powders to achieve few-layer MoS2 (FL-MoS2) nanosheets in the solvent of N-methyl-2-pyrrolidone (NMP) with polyvinylpyrrolidone (PVP) molecules. The synergistic effect of ultrasonication and sand milling highly enhanced the exfoliation efficiency, and the precursor of natural molybdenite powders minimizes the synthetic cost of FL-MoS2 nanosheets. The exfoliation of natural molybdenite powders was conducted in a home-made CUM system, mainly consisting of an ultrasonic cell disruptor and a ceramic sand mill. The samples were characterized by X-ray diffraction, UV-vis spectra, Raman spectra, FT-IR, SEM, TEM, AFM, and N2 adsorption-desorption. The factors that influence the exfoliation in the CUM process, including the initial concentration of natural molybdenite powders ( C in, 15-55 g L-1), ultrasonic power ( P u, 200-350 W), rotation speed of sand mill ( ω s, 1500-2250 r.p.m), exfoliation time ( t ex, 0.5-6 h), and the molar ratio of PVP unit to MoS2 ( R pm, 0-1), were systematically investigated. Under the optimal CUM conditions (i.e., C in = 45 g L-1, P u = 280 W, ω s = 2250 r.p.m and R pm = 0.5), the yield at t ex = 6 h reaches 21.6 %, and the corresponding exfoliation rate is as high as 1.42 g L-1 h-1. The exfoliation efficiency of the CUM mode is much higher than that of either the ultrasonication (U) mode or the milling (M) mode. The synergistic mechanism and influencing rules of the CUM process in exfoliating natural molybdenite powders were elaborated. The as-obtained FL-MoS2 nanosheets have a high specific surface area of 924 m2 g-1 and show highly enhanced electrocatalytic performance in hydrogen evolution reaction and good electrochemical sensing property in detecting ascorbic acid. The CUM process

  7. Ab-initio and DFT calculations on molecular structure, NBO, HOMO-LUMO study and a new vibrational analysis of 4-(Dimethylamino) Benzaldehyde.

    Science.gov (United States)

    Rocha, Mariana; Di Santo, Alejandro; Arias, Juan Marcelo; Gil, Diego M; Ben Altabef, Aída

    2015-02-05

    The experimental and theoretical study on the molecular structure and a new vibrational analysis of 4-(Dimethylamino) Benzaldehyde (DMABA) is presented. The IR and Raman spectra were recorded in solid state. Optimized geometry, vibrational frequencies and various thermodynamic parameters of the title compound were calculated using DFT methods and are in agreement with the experimental values. A detailed interpretation of the IR and Raman spectra of the title compound were reported. The stability of the molecule arising from hyper-conjugative interactions and charge delocalization has been analyzed using NBO analysis and AIM approach. The HOMO and LUMO analysis were used to determine the charge transfer within the molecule and some molecular properties such as ionization potential, electron affinity, electronegativity, chemical potential, hardness, softness and global electrophilicity index. The TD-DFT approach was applied to assign the electronic transitions observed in the UV-visible spectrum measured experimentally. Molecular electrostatic potential map was performed by the DFT method. According to DSC measurements, the substance presents a melting point of 72.34°C and decomposes at temperatures higher than 193°C. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Spectrophotometric determination of platinum(IV) in alloys, complexes, environmental, and pharmaceutical samples using 4-[N,N-(diethyl)amino] benzaldehyde thiosemicarbazone.

    Science.gov (United States)

    Naik, P Parameshwara; Karthikeyan, J; Shetty, A Nityananda

    2010-12-01

    4-[N,N-(Diethyl)amino] benzaldehyde thiosemicarbazone (DEABT) is proposed as an analytical reagent for the spectrophotometric determination of platinum(IV). The DEABT forms 1:2 yellow complex with Pt(IV), which is sparingly soluble in water and completely soluble in water-ethanol-DMF medium. The Pt(IV)-DEABT complex shows maximum absorbance at 405 nm. Beer's law is valid up to 7.80 μg cm(-3), and optimum concentration range for the determination of platinum(IV) is 0.48-7.02 μg cm(-3). The molar absorptivity and Sandell's sensitivity of the method are found to be 1.755 × 10(4) dm(3) mol(-1) cm(-1) and 0.0012 μg cm(-2), respectively. The relative error and coefficient of variation (n=6) for the method does not exceed ± 0.43% and 0.35%, respectively. Since the method tolerates a number of metal ions commonly associated with platinum, it can be employed for the determination of platinum in environmental samples, pharmaceutical samples, alloys, catalysts, and complexes. The method is rapid as the Pt(IV)-DEABT complex is soluble in water-ethanol-DMF medium and not requiring any time consuming extraction method for the complex.

  9. Continuous irradiation induced luminescence from benzophenone, 4,4{prime}-dichlorobenzophenone, and 4-(dimethylamino)benzaldehyde in solid environments and its pressure dependence

    Energy Technology Data Exchange (ETDEWEB)

    Dreger, Z.A.; Drickamer, H.G. [Univ. of Illinois, Urbana, IL (United States)

    1997-02-20

    We report a strong emission change induced by continuous light irradiation in two ketones, benzophenone and 4,4{prime}-dichlorobenzophenone, and an aldehyde, 4-(dimethylamino)benzaldehyde, in their crystalline state as well as dissolved in solid polymers. With prolonged laser irradiation, a time evolution of the emission intensity shows complex features, but two clear competing trends can be distinguished: an increase and/or decrease of the emission intensity. It is shown that these trends may be a result of creation of either an emissive or a nonemissive species. The relative importance of these two pathways is significantly dependent on the type of medium and external pressure. The most characteristic feature of these dependencies is the fact that in crystalline environments, in contrast to polymers, the emission intensity at all pressures only decreases. A kinetic model is developed that assumes the lowest triplet state as the origin of the high photoreactivity of these molecules, causing their emission intensity change. This model embraces the observations either in crystalline or polymeric environments and is solved for two limiting cases: a predominance of the hydrogen abstraction reaction from the polymer or a predominance of the ionization due to biphotonic excitation of the triplet state. These processes are assumed responsible, respectively, for the creation of emissive and nonemissive photoproducts. 29 refs., 19 figs., 2 tabs.

  10. Ursolic acid benzaldehyde chalcone leads to inhibition of cell proliferation and arrests cycle in G1/G0 phase in ovarian cancer

    Directory of Open Access Journals (Sweden)

    Yan Jia

    2015-06-01

    Full Text Available In the present study, the effect of ursolic acid benzaldehyde chalcone (UABC on ovarian carcinoma cells was studied. The results revealed that ovarian carcinoma cells on UABC treatment increased Sub-G1 cell population, increased rate of cell apoptosis and morphological changes in mitochondrial membrane. In OVCAR 432 cells treatment with UABC increased the Sub-G1 cell population to 72.3% and growth inhibition rate of >72%. Treatment with 20 µM of UABC for 48 hours, led to an induction of apoptosis in 67.2% and induced morphological changes in OVCAR 432 cells. The Western blot results showed high concentration of cytochrome c in the cell cytosol after 48 hours of UABC treatment. Treatment of RMS-13 cells with UABC resulted in inhibition of GLI1, GLI2, PTCH1, and IGF2 genes. In addition, we found a significant reduction in hedgehog activity of RMS-13 cells after UABC treatment by means of a hedgehog-responsive reporter assay. Therefore, UABC can be a promising agent for the treatment of ovarian carcinoma.

  11. Extractive spectrophotometric determination of copper(II in water and alloy samples with 3-methoxy-4-hydroxy benzaldehyde-4-bromophenyl hydrazone (3,4-MHBBPH

    Directory of Open Access Journals (Sweden)

    D. REKHA

    2007-03-01

    Full Text Available A facile, sensitive and selective extractive spectrophotometricmethod was developed for the determination of copper(II in various water and alloy samples using a newly synthesized reagent, 3-methoxy-4-hydroxy benzaldehyde 4-bromophenyl hydrazone (3,4-MHBBPH. Copper(II forms a orange colored complex with (3,4-MHBBPH in acetate buffermedium (pH 4 which increases the sensitivity and the complexwas extracted into chloroform. Under optimum conditions, the maximum absorption of the chloroform extract was measured at 462 nm. The Beer law was obeyed in the range of 0.20 to 4.0 mg ml-1 of copper. The molar absorptivity and the Sandell's sensitivity of the complex were 2.0520 ´ 104 mol-1 cm-1 and 0.2540 mg cm-2, respectively. The detection limit was found to be 0.0270 mg mL-1. Adetailed study of various interfering ions made the method more sensitive. The method was successfully applied for the determination of Cu(II in water and alloy samples. The performance of the present method was evaluated in terms of Student 't' test and Variance ratio 'f ' test, which indicate the significance of the present method over reported methods.

  12. Effect of environment on pressure-induced emission of benzophenone, 4,4{prime}-dichlorobenzophenone, and 4-(dimethylamino)benzaldehyde in solid media

    Energy Technology Data Exchange (ETDEWEB)

    Dreger, Z.A.; Drickamer, H.G. [Univ. of Illinois, Urbana, IL (United States)

    1997-02-20

    The pressure-induced emission of three aromatic carbonyls - benzophenone (BP), 4,4{prime}-dichlorobenzophenone (DCBP), and 4-(dimethylamino)benzaldehyde (DMABA) - dissolved in solid polymers and also in their crystalline state has been studied. Under pressure all compounds dissolved in polymers reveal a significant enhancement of the luminescence emission in the low-pressure region. The degree of increase is strongly dependent on the type of polymer. DMABA exhibits both fluorescence and phosphorescence, whereas BP and DCBP molecules show only phosphorescence. For all these molecules a model based on the increase with increasing pressure of the amount of {pi},{pi}{sup *} character in the initially predominately n,{pi}{sup *} triplet state is proposed to account for the observed increase of the emission intensity. In the case of DMABA it is proposed that the increase of the {pi},{pi}{sup *} character in the triplet state increases the emission intensity in two concurrent steps: by an increase of the radiative rate from the triplet state and by a decrease of the intersystem crossing rate between singlet and triplet states. The first factor increases phosphorescence intensity, and the second one effects the fluorescence. In the case of BP and DCBP, where the intersystem crossing process is very fast, the increase of pressure increases mainly the radiative rate of the lowest triplet state. 22 refs., 8 figs.

  13. Crystal Structures of Two Calix[4]arene Isomers with Benzaldehyde Moiety and Their Photophysical Properties with Terbium(Ⅲ) Ions

    Institute of Scientific and Technical Information of China (English)

    王浩; 张衡益; 刘育

    2005-01-01

    Two calix[4]arene isomers with benzaldehyde moieties, i.e., 5,11,17,23-tetra-tert-butyl-25,27-bis[2-(o-formyl-phenoxy)ethoxy]-26,28-dihydroxycalix[4]arene (3) and 5,11,17,23-tetra-tert-butyl-25,27-bis[2-(p-formylphenoxy)-ethoxy]-26,28-dihydroxycalix[4]arene (4), were synthesized according to a newly designed route in high yields, and their crystal structures have been determined by X-ray crystallographic study. The photophysical behavior on complexation of calix[4]arene derivatives 3 and 4 with terbium(Ⅲ) nitrate was investigated in anhydrous acetonitrile at 25℃ by UV-Vis and fluorescence spectroscopies. The crystallographic structure of 3 indicated that the eight oxygen atoms formed a preorganized ionophoric cavity due to intramolecular π-π stacking, which could encapsulate lanthanide ions tightly. In sharp contrast, the compound 4 formed a linear array by intermolecular π-π stacking, hence the oxygen atoms of pendant arms could not coordinate with metal ions, giving a poor binding ability to Tb3+. The absorption spectra of 3 with Tb3+ showed clearly a new broad intense absorption at 385nm. Interestingly, the narrow emission line spectrum has also been observed for compound 3 with Tb3+, and the results obtained were discussed from the viewpoint of energy transfer mechanism between host structures and the properties of lanthanide ions.

  14. Investigation of antitumor potential of Ni(II) complexes with tridentate PNO acylhydrazones of 2-(diphenylphosphino)benzaldehyde and monodentate pseudohalides.

    Science.gov (United States)

    Čobeljić, Božidar; Milenković, Milica; Pevec, Andrej; Turel, Iztok; Vujčić, Miroslava; Janović, Barbara; Gligorijević, Nevenka; Sladić, Dušan; Radulović, Siniša; Jovanović, Katarina; Anđelković, Katarina

    2016-04-01

    Square-planar azido Ni(II) complex with condensation product of 2-(diphenylphosphino)benzaldehyde and Girard's T reagent was synthesized and its crystal structure was determined. Cytotoxic activity of the azido complex and previously synthesized isothiocyanato, cyanato and chlorido Ni(II) complexes with this ligand was examined on six tumor cell lines (HeLa, A549, K562, MDA-MB-453, MDA-MB-361 and LS-174) and two normal cell line (MRC-5 and BEAS-2B). All the investigated nickel(II) complexes were cytotoxic against all tumor cell lines. The newly synthesized azido complex showed selectivity to HeLa and A549 tumor cell lines compared to the normal cells (for A549 IC50 was similar to that of cisplatin). Azido complex interferes with cell cycle phase distribution of A549 and HeLa cells and possesses nuclease activity towards supercoiled DNA. The observed selectivity of the azido complex for some tumor cell lines can be connected with its strong DNA damaging activity.

  15. Ab-initio and DFT calculations on molecular structure, NBO, HOMO-LUMO study and a new vibrational analysis of 4-(Dimethylamino) Benzaldehyde

    Science.gov (United States)

    Rocha, Mariana; Di Santo, Alejandro; Arias, Juan Marcelo; Gil, Diego M.; Altabef, Aída Ben

    2015-02-01

    The experimental and theoretical study on the molecular structure and a new vibrational analysis of 4-(Dimethylamino) Benzaldehyde (DMABA) is presented. The IR and Raman spectra were recorded in solid state. Optimized geometry, vibrational frequencies and various thermodynamic parameters of the title compound were calculated using DFT methods and are in agreement with the experimental values. A detailed interpretation of the IR and Raman spectra of the title compound were reported. The stability of the molecule arising from hyper-conjugative interactions and charge delocalization has been analyzed using NBO analysis and AIM approach. The HOMO and LUMO analysis were used to determine the charge transfer within the molecule and some molecular properties such as ionization potential, electron affinity, electronegativity, chemical potential, hardness, softness and global electrophilicity index. The TD-DFT approach was applied to assign the electronic transitions observed in the UV-visible spectrum measured experimentally. Molecular electrostatic potential map was performed by the DFT method. According to DSC measurements, the substance presents a melting point of 72.34 °C and decomposes at temperatures higher than 193 °C.

  16. Synthesis, spectroscopic investigations and computational study of 4-((9,10-dioxo-9,10-dihydroanthracen-1-yl)oxy)benzaldehyde

    Science.gov (United States)

    Kanaani, A.; Ajloo, D.; Kiyani, H.; Farahani, M.

    2014-04-01

    The molecular structure, vibrational frequencies, corresponding vibrational assignments of 4-((9,10-dioxo-9,10-dihydroanthracen-1-yl)oxy)benzaldehyde in “trans” and “ana” forms have been investigated by UV-Vis, FT-IR and NMR spectroscopy as well as density functional theory (DFT) B3LYP method with 6-311++G(d,p) basis set. The vibrational analysis of the two forms of cited compound was performed by means of infrared absorption spectroscopy in combination with theoretical simulations. The obtained geometrical parameters and wavenumbers of vibrational normal modes from the DFT method were in good consistency with the experimental values. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by GIAO method. Computed molecular orbital and time dependent DFT oscillator renderings agree closely with experimental observations. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. In order to predict the reactive sites, a molecular electrostatic potential map (MEP) for the title compound was obtained. Transition structures were calculated by QST3 and IRC methods which yielded the potential energy surface and activation energy.

  17. 2,4-dihydroxy benzaldehyde derived Schiff bases as small molecule Hsp90 inhibitors: rational identification of a new anticancer lead.

    Science.gov (United States)

    Dutta Gupta, Sayan; Revathi, B; Mazaira, Gisela I; Galigniana, Mario D; Subrahmanyam, C V S; Gowrishankar, N L; Raghavendra, N M

    2015-04-01

    Hsp90 is a molecular chaperone that heals diverse array of biomolecules ranging from multiple oncogenic proteins to the ones responsible for development of resistance to chemotherapeutic agents. Moreover they are over-expressed in cancer cells as a complex with co-chaperones and under-expressed in normal cells as a single free entity. Hence inhibitors of Hsp90 will be more effective and selective in destroying cancer cells with minimum chances of acquiring resistance to them. In continuation of our goal to rationally develop effective small molecule azomethines against Hsp90, we designed few more compounds belonging to the class of 2,4-dihydroxy benzaldehyde derived imines (1-13) with our validated docking protocol. The molecules exhibiting good docking score were synthesized and their structures were confirmed by IR, (1)H NMR and mass spectral analysis. Subsequently, they were evaluated for their potential to suppress Hsp90 ATPase activity by Malachite green assay. The antiproliferative effect of the molecules were examined on PC3 prostate cancer cell lines by adopting 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay methodology. Finally, schiff base 13 emerged as the lead molecule for future design and development of Hsp90 inhibitors as anticancer agents.

  18. Study on preparation and bonding properties of natural rubber latex grafted and modified by HEMA%HEMA接枝改性天然胶乳的制备及其粘接性能研究

    Institute of Scientific and Technical Information of China (English)

    卫飞云; 刘宏超; 曹端林; 余和平

    2013-01-01

    以甲基丙烯酸羟乙酯(HEMA)作为天然胶乳(NRL)的接枝改性剂,采用乳液聚合法制备了NR-g-HEMA[HEMA接枝NR(天然橡胶)]胶乳;然后以此为基体,并以水溶性松香树脂为增黏树脂、邻苯二甲酸二丁酯(DBP)为增塑剂等,制备相应的NR-g-HEMA胶粘剂;最后,用该胶粘剂压制胶合板,并对胶合板的粘接性能进行了测定.结果表明:采用单因素试验法优选出制备NR-g-HEMA胶乳的最佳工艺条件为m(干态单体)∶m(NRL)∶m(引发剂)∶m(活化剂)∶m(交联剂)=20∶100∶0.2∶0.2∶0.1、反应时间为8h和反应温度为16℃,此时相应胶合板的剪切强度(1.88MPa)符合Ⅲ类胶合板的指标要求.%Abstract:With hydroxyethyl methacrylate (HEMA) as graft modifier of natural rubber latex (NRL),a NR-g-HEMA[NR(natural rubber) grafted by HEMA] latex was prepared by emulsion polymerization.Then,with NR-g-HEMA latex as matrix,water-soluble rosin resin as tackifying resin,and dibutyl phthalate(DBP) as plasticizer,a corresponding NR-g-HEMA adhesive was prepared.Finally,the plywood was pressed by the adhesive,and the bongding properties of plywood were mensurated.The results showed that the optimal process conditions of preparing NR-g-HEMA latex were preferred by single-factor experiment method when mass ratio of m(dry monomer)∶m(NRL)∶m(initiator)∶m(activating agent)∶m(cross linker) was 20∶100∶0.2∶0∶2∶0.1,reaction time was 8h and reaction temperature was 16℃.Here,the shear strength (1.88MPa) of corresponding plywood could meet index requirement of Ⅲ class-plywood.

  19. New synthetic way to prepare 2-aryl-8-(piperidin-4-yl)-5, 7-dimethoxy-4H-chromen-4-one as key intermediate for CDK inhibitor

    Institute of Scientific and Technical Information of China (English)

    Yan Ling Li; Hao Fang; Wen Fang Xu; Bing He Wang

    2008-01-01

    As an important intermediate to study cyclin-dependent kinase (CDK) inhibitors, 2-aryl-8-(piperidin-4-yl)-5,7-dimethoxy-4H-chromen-4-one derivatives were prepared using β-diketone route with low yield. In our study, chalcone route has been investigatedand the result suggested that the benzaldehydes substituted with electron-donating group give much better yield than β-diketoneroute. This new method will be an efficient way to start further research on new anticancer flavonoids.2008 Hao Fang. PuNished by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

  20. 天然蒙脱石/植酸酶复合载体制备及其植酸磷水解活性研究%Preparation of Phytase/Natural Montmorillonite Composite and Its Phytate Hydrolysis Activity

    Institute of Scientific and Technical Information of China (English)

    张闻中; 徐芳; 徐建雄

    2013-01-01

      通过吸附过程制备了天然蒙脱石/植酸酶复合载体并系统探讨其催化水解植酸磷活性.结果表明,天然蒙脱石固载植酸酶符合Elovich 动力学模型,固载等温曲线满足 Langmuir 方程,植酸酶最大固载容量为1.48 mg/mg;天然蒙脱石/植酸酶复合载体作为微型固定化酶反应器催化水解植酸磷,同自由植酸酶相比较,温度耐受性、抗蛋白酶水解能力均有效改善;适宜的 pH 值适用范围为4.0~4.5;重复利用5次后酶活保留40%以上.天然蒙脱石/植酸酶复合载体作为饲料添加剂可有效减少植酸酶制剂投加量,提高植酸磷有效利用率,溯源性降低畜禽养殖业“磷”污染排放.%Phytase/natural montmorillonite composite was prepared by adsorption process and the composite’s enzymatic activity for phytate hydrolysis was studied. The results showed that: the kinetic for adsorption of phytase onto natural montmorillonite could be best described by Elovich model, and the adsorptive isotherms fit for Langmuir model, with the maximum monolayer adsorption capacity of 1.48 mg/mg. The phytase/natural montmorillonite composites served as micro enzyme immobilized reactor for phytate hydrolysis. In comparison to free phytase, the relevant properties of the composites were effectively enhanced in view of the temperature tolerance and anti-proteolytic capability. The suitable pH media range for the composites in real practice was from 4.0 to 4.5. The enzymatic activity retained more than 40% after five testing cycles. Overall, the development of phytase/natural montmorillonite composite as feed additives could improve the availability of phosphorus from phytate and reduce the dosage of phytase, which contribute to the reduction of phosphorus emissions from livestock and poultry waste.

  1. Effects of the aldehyde dehydrogenase inhibitor disulfiram on the plasma pharmacokinetics, metabolism, and toxicity of benzaldehyde dimethane sulfonate (NSC281612, DMS612, BEN) in mice

    Science.gov (United States)

    Parise, Robert A.; Beumer, Jan H.; Clausen, Dana M.; Rigatti, Lora H.; Ziegler, Judy A.; Gasparetto, Maura; Smith, Clayton A; Eiseman, Julie L.

    2013-01-01

    Purpose Benzaldehyde dimethane sulfonate (DMS612, NSC281612, BEN) is an alkylator with activity against renal cell carcinoma, currently in phase I trials. In blood, BEN is rapidly metabolized into its highly reactive carboxylic acid (BA), presumably the predominant alkylating species. We hypothesized that BEN is metabolized to BA by aldehyde dehydrogenase (ALDH) and aimed to increase BEN exposure in blood and tissues by inhibiting ALDH with disulfiram thereby shifting BA production from blood to tissues. Methods Female CD2F1 mice were dosed with 20 mg/kg BEN iv alone or 24 h after 300 mg/kg disulfiram ip. BEN, BA and metabolites were quantitated in plasma and urine, and toxicities were assessed. Results BEN had a plasma t½ <5 min and produced at least 12 products. The metabolite half-lives were <136 min. Disulfiram increased BEN plasma exposure 368-fold, (AUC0-inf from 0.11 to 40.5 mg/L•min), while plasma levels of BA remained similar. Urinary BEN excretion increased (1.0% to 1.5% of dose) while BA excretion was unchanged. Hematocrit, white blood cells counts and %lymphocytes decreased after BEN administration. Co-administration of disulfiram appeared to enhance these effects. Profound liver pathology was observed in mice treated with disulfiram and BEN. Conclusions BEN plasma concentrations increased after administration of disulfiram, suggesting that ALDH mediates the rapid metabolism of BEN in vivo, which may explain the increased toxicity seen with BEN after administration of disulfiram. Our results suggest that the co-administration of BEN with drugs that inhibit ALDH or to patients that are ALDH deficient may cause liver damage. PMID:24061865

  2. Core-Shell Structural CdS@SnO₂ Nanorods with Excellent Visible-Light Photocatalytic Activity for the Selective Oxidation of Benzyl Alcohol to Benzaldehyde.

    Science.gov (United States)

    Liu, Ya; Zhang, Ping; Tian, Baozhu; Zhang, Jinlong

    2015-07-01

    Core-shell structural CdS@SnO2 nanorods (NRs) were fabricated by synthesizing SnO2 nanoparticles with a solvent-assisted interfacial reaction and further anchoring them on the surface of CdS NRs under ultrasonic stirring. The morphology, composition, and microstructures of the obtained samples were characterized by field-emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and nitrogen adsorption-desorption. It was found that SnO2 nanoparticles can be tightly anchored on the surface of CdS NRs, and the thickness of SnO2 shells can be conveniently adjusted by simply changing the addition amount of SnO2 quantum dots. UV-vis diffuse reflectance spectrum indicated that SnO2 shell layer also can enhance the visible light absorption of CdS NRs to a certain extent. The results of transient photocurrents and photoluminescence spectra revealed that the core-shell structure can effectively promote the separation rate of electron-hole pairs and prolong the lifetime of electrons. Compared with the single CdS NRs, the core-shell structural CdS@SnO2 exhibited a remarkably enhanced photocatalytic activity for selective oxidation of benzyl alcohol (BA) to benzaldehyde (BAD) under visible light irradiation, attributed to the more efficient separation of electrons and holes, improved surface area, and enhanced visible light absorption of core-shell structure. The radical scavenging experiments proved that in acetonitrile solution, ·O2- and holes are the main reactive species responsible for BA to BAD transformation, and the lack of ·OH radicals is favorable to obtaining high reaction selectivity.

  3. 40 CFR 1502.6 - Interdisciplinary preparation.

    Science.gov (United States)

    2010-07-01

    ... § 1502.6 Interdisciplinary preparation. Environmental impact statements shall be prepared using an inter-disciplinary approach which will insure the integrated use of the natural and social sciences and...

  4. 纳米纤维素/天然橡胶复合材料的制备及表征%Preparation and Characterization of Nano -crystalline Cellulose/Natural Rubber (NCC/NR) Composites *

    Institute of Scientific and Technical Information of China (English)

    陈红莲; 高天明; 黄茂芳; 廖建和

    2012-01-01

    Blended natural rubber (NR) with different amount of nano - cellulose cellulose ( NCC ) were usea to prepare nano -crystalline cellulose/natural rubber (NCC/NR) composites. The resulting products were characterized by scanning electron microscopy ( SEM), mechanical property testing, thermo - gravimetric analysis and dynamic mechanical analysis(DMA). Results showed that NCC were homogeneously distributed throughout NR matrix, which led to the en- hancement on mechanical properties. Moreover, the storage modulus ( E' ) of composites went up with the increment of NCC loadings and loss factor (tang) decreases, and the addition of NCC had less impact on the thermal stability of NR matrix.%采用共混法制备不同比率含量的纳米纤维素/天然橡胶(NCC/NR)复合材料,通过扫描电镜、力学性能、热稳定性以及动态力学性能的测定分析表明:纳米纤维素能较均匀分散在橡胶基质中,对天然橡胶起到较好的补强效果,复合材料的储能模量逐步增大,损耗因子逐步减小,纳米纤维素的加入对天然橡胶的热稳定性影响不大。

  5. Application of the extended real associated solution (ERAS) theory to excess molar enthalpies of benzaldehyde + 1-alkanols (C{sub 1} to C{sub 5}) at T = 298.15 K

    Energy Technology Data Exchange (ETDEWEB)

    Iloukhani, H., E-mail: iloukhani@basu.ac.ir [Department of Physical Chemistry, Faculty of Chemistry, University of Bu-Ali Sina, Hamedan 65174 (Iran, Islamic Republic of); Fattahi, M. [Department of Physical Chemistry, Faculty of Chemistry, University of Bu-Ali Sina, Hamedan 65174 (Iran, Islamic Republic of)

    2011-11-15

    Highlights: > Enthalpy of binary mixtures of {l_brace}benzaldehyde + 1-alkanols{r_brace} (C{sub 1} to C{sub 5}) determined. > Excess molar enthalpy, partial molar enthalpy, and intermolecular interaction functions were calculated. > Excess molar enthalpy was correlated as a function of mole fraction by using the Redlich-Kister equation. > The experimental results have been used to test the applicability of the ERAS-model, Wilson and NRTL equations. - Abstract: This paper reports excess molar enthalpies, H{sub m}{sup E}, for the binary mixtures of {l_brace}1-alkanols (2), namely, {l_brace}methanol, ethanol, 1-propanol, 1-butanol, and 1-pentanol{r_brace} with benzaldehyde (1){r_brace} at T = 298.15 K at ambient pressure over a whole range of mole fraction. The sign of H{sub m}{sup E} for all systems are positive and the magnitude of H{sub m}{sup E} values with increasing of chain length, increase. The Redlich-Kister polynomial equation was used to correlate H{sub m}{sup E}. The excess partial molar enthalpies of benzaldehyde, H{sub m,1}{sup E}, excess partial molar enthalpies of 1-alkanols (C{sub 1} to C{sub 5}), H{sub m,2}{sup E}, and excess partial molar enthalpies at infinite dilution, H{sub m,i}{sup E,0}, are calculated according to experimental excess molar enthalpies and Redlich-Kister polynomial equation. The extracted date were used to evaluated the so-called intermolecular interaction functions {partial_derivative}H{sub m,i}{sup E}/{partial_derivative}x{sub i} and {partial_derivative}H{sub m,i}{sup E}/{partial_derivative}x{sub j} in terms of enthalpy. The ERAS, Wilson and NRTL models have been applied for describing the H{sub m}{sup E}.

  6. Natural Rubber Latex Modified by Nano SiO2 to Prepare Medical Gloves%用纳米SiO2改性胶乳制备新型医用橡胶手套

    Institute of Scientific and Technical Information of China (English)

    敖宁建

    2005-01-01

    Nano SiO2 modified natural rubber latex treated by ultrasonic and special dispersing agent was used to prepare medical gloves, and the mechanical and aging properties of the product were investigated. The results show that the tensile strength of the glove with 0.5% (mass fraction) nano SiO2 was 20.2MPa when the contrast was 15.9MPa. After 2% (mass fraction) nano SiO2 was filled in the latex, the tensile strength of the product increased to 25.5MPa. With the increase of the nano SiO2 content, strength at 300% and 500% elongation of the products increased gradually. Addition of nano SiO2 particles didn't change the elongation at break and elasticity of the glove. After 33 hours aging in hot air at 100℃, the tensile strength of the glove with 2% (mass fraction) nano SiO2 was as high as 12.7MPa.

  7. Research development of preparation natural functional food additives from bacteria%利用细菌开发天然功能性食品添加剂研究进展

    Institute of Scientific and Technical Information of China (English)

    李述日; 吴清平; 吴军林

    2011-01-01

    主要从两个方面介绍了利用细菌开发天然功能性食品添加剂的发展状况:一方面是关于益生菌(双歧杆菌和乳酸杆菌)的作用机理、医疗保健功能,以及开发针对不同人群的特定益生菌功能性食品添加剂的发展前景;另一方面是关于细菌代谢产物(乳酸链球菌素、溶菌酶、聚赖氨酸)的作用机理、医疗保健功能,以及开发细菌素相关的新型功能性食品添加剂的发展前景.%The progress of preparation natural functional food additives from bacteria was introduced from two aspects. On the one hand is about the mechanism and health care functions of probiotics (lactobacillus and bifidobacterium) ,and the prospects of developing specific probiotic functional food additives for different groups of people. On the other hand is about the mechanism and health care functions of bacterial metabolites (nisin,lysozyme, polylysine) ,and the prospects of developing the new bacteriocin-related functional food additives.

  8. 纳米纤维素晶须/壳聚糖天然可降解复合膜的制备与性能%Preparation and Properties of Nanocellulose Whiskers/Chitosan Natural Biodegradable Composite Films

    Institute of Scientific and Technical Information of China (English)

    徐寅; 王家俊; 刘幸幸; 吴鲜鲜

    2011-01-01

    Natural biodegradable composite films are prepared from nanocellulose whiskers(NCW) as reinforcement and chitosan(CS) as matrix via solution casting technique. The structures of the films are characterized by SEM, FT-IR, and XRD; Dynamic mechanical properties, tensile performance under dry and wet conditions are also tested. The results show that the composite films exhibite good miscibility; NCW significantly increases films' storage modulus, tensile modulus and strength. NCW promises to further widen applications and areas of CS material.%以纳米纤维素晶须(NCW)为增强体、壳聚糖(CS)为基体,通过流延法制得天然可降解复合膜.通过电子显微镜( SEM)、红外光谱(FT-IR)、X射线衍射(XRD)等手段对复合膜进行结构表征,并对复合膜的动态力学性能、干湿态拉伸性能进行了测试.结果表明:NCW与CS具有很好的相容性;NCW的加入显著提高了CS膜的储能模量、拉伸模量和拉伸强度.NCW能够进一步拓宽CS材料的应用领域和价值.

  9. Preparation of ZnO nanorod photo-anode and its natural dye sensitization research%ZnO纳米棒光阳极的制备及其天然染料敏化研究

    Institute of Scientific and Technical Information of China (English)

    张晓楠; 王青; 戴剑锋; 姜金龙; 李维学; 魏学刚

    2012-01-01

    ZnO seed layers were prepared by sol-gel method and spin coating method on the substrate which is FTO/glass. The prepared substrates with seed layer were immersed into the precursor solution which contains zinc nitrate and hexamethylenetetramine(HMT) under different growth time and solution concentrations. The ZnO nanorod electrodes were characterized by XRD and SEM. We obtain orderly ZnO nanorod array at 90 ℃ with growth time of 4 h,the solution concentration of 0. 025 mol/L,and the average diameter about 80 nm. Using the natural dye extracted from fresh strawberries and mulberries as sensitizers,the natural dye sensitized ZnO nanorod film electrodes were prepared and the dye sensitized solar cells were fabricated. The absorption spectra of sensitized electrodes were characterized,and the result shows that the electrode with mulberries as sensitizer has a good absorbance in visible light area. In simulation,the solar cell with mulberries as sensitizer has excellent photoelectric characteristics,a filling factor of 0. 37 ,a shorvcircuit photocurrent of 189μA,an open-circuit voltage of 228.75 mV,and an optic-electric conversion efficiency of 5.5 × 10-4.%采用溶胶-凝胶法和旋转涂覆法在FTO导电玻璃上制备ZnO种子层,以Zn(NO3)2和六亚甲基四胺(HMT)的混合溶液为生长液在ZnO种子层上制备出ZnO纳米棒薄膜,利用x射线衍射(XRD)、扫描电镜(SEM)对ZnO种子层及纳米棒薄膜的晶相及表面微观形貌进行了表征;研究了生长液浓度、生长时间对ZnO纳米棒薄膜生长的影响。实验表明,制备排列整齐的ZnO纳米棒阵列薄膜最佳条件为90℃环境下,基底竖直放置在0.025mol/L的生长液中,生长4h,纳米棒平均直径80nm左右。从新鲜草莓、桑葚中提取天然色素,对ZnO纳米棒电极进行敏化,组装成光电池;测试敏化电极的吸收光谱及光电池的伏安特性曲线。结果表明,桑葚色素在可见光区有

  10. 天然花青素提取物与壳聚糖明胶复合膜的制备和表征%Preparation and characterization of chitosan/gelatin composite films incorporated with four natural pigments

    Institute of Scientific and Technical Information of China (English)

    邹小波; 王圣; 石吉勇; 翟晓东; 黄晓玮; 赵号

    2016-01-01

    In order to obtain antioxidant active packaging materials, chitosan/gelatin (CG) composite films incorporated with 4 kinds of natural pigments were developed. The 4 kinds of natural pigments were extracted from red cabbage, black rice, rose and blueberry, respectively, and the anthocyanins content in each pigment was measured. The films were prepared by casting and solvent-evaporation method. The composite film-forming solutions were prepared by dispersing chitosan (1%) in the aqueous solution of 0.5% glacial acetic acid mixed with 1% gelatin at the volume ratio of 7:3. As for the film, the final concentration of anthocyanins in the film was established as 25% of the total volume of the mixture of hydrogels. The physical, mechanical, antioxidant and structural properties of the composite films were also investigated. Physical and mechanical properties of the films showed that the CG film had a lower water-vapor permeability (10.69×10-11 g/(m·s·Pa)) when not incorporated with natural pigments. The incorporation of rose pigments led to the reduction of the water-vapor permeability while the other extracts did inversely. The lowest water-vapor permeability value was 10.05×10-11 g/(m·s·Pa) and the incorporation of blueberry pigment reached the maximum level of 14.52×10-11 g/(m·s·Pa). Furthermore, the addition of rose pigment led to a reduction of elongation at break but an increase of tensile strength, with the lowest elongation at break of 37.66% and the greatest tensile strength of 27.03 MPa. However, black rice pigment extract led to an increase of elongation at break from 52.59% to 57.67% compared with CG film without incorporating natural pigments. Fourier transform infrared spectroscopy (FTIR) showed that the incorporation of natural pigments brought about the interactions between its hydroxyl groups and the amino groups of chitosan. Significant structural transformation could be observed from scanning electron microscope (SEM), and each film showed

  11. Solution preparation

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, M.G.

    1982-01-01

    Reviewed in this statement are methods of preparing solutions to be used in laboratory experiments to examine technical issues related to the safe disposal of nuclear waste from power generation. Each approach currently used to prepare solutions has advantages and any one approach may be preferred over the others in particular situations, depending upon the goals of the experimental program. These advantages are highlighted herein for three approaches to solution preparation that are currently used most in studies of nuclear waste disposal. Discussion of the disadvantages of each approach is presented to help a user select a preparation method for his particular studies. Also presented in this statement are general observations regarding solution preparation. These observations are used as examples of the types of concerns that need to be addressed regarding solution preparation. As shown by these examples, prior to experimentation or chemical analyses, laboratory techniques based on scientific knowledge of solutions can be applied to solutions, often resulting in great improvement in the usefulness of results.

  12. Preparation and properties of amorphous FeCo alloy nanoparticles/natural rubber composites%铁钴纳米合金/天然橡胶复合材料制备及性能研究

    Institute of Scientific and Technical Information of China (English)

    王凤平; 薛行华; 马立胜; 蔡静瑶; 符新

    2011-01-01

    采用液相还原法制备铁钴合金纳米粒子(nano-FeCo),通过不同的制备工艺与天然胶乳共混,制备铁钴纳米合金/天然橡胶复合材料(NR/nano-FeCo).利用X射线衍射仪(XRD)和透射电子显微镜(TEM)对样品结构进行表征.并考察了复合材料的力学性能及不同制备工艺对复合材料性能的影响.结果表明,液相还原法制备的nano-FeCo粒子为无定形结构,粒径约为70 nm.在天然橡胶(NR)基体中分散均匀,分散相粒径在100 nm左右;随着纳米粒子的加入,有效地提高了复合材料的力学性能,同时,可提高NR的热老化性能.NR/nano-FeCo的最佳制备工艺是乳液共混法.%FeCo alloy nanoparticles(nano-FeCo) were synthesized by reduction process in liquid phase. Then the nano-FeCo particles were coagulated with natural rubber latex to prepare FeCo alloy nanoparticles/natural rubber composites(NR/nano-FeCo). The structure and properties of the samples were investigated by X-ray powder diffraction(XRD) and transmission electron microscopy (TEM). And its mechanical properties and different processes were studied. The results showed that nano-FeCo particles are amorphous. The average size of the particles is about 70nm. The nano-FeCo particles are homogenously distributed throughout NR matrix, and the particle size of disperse phase is about 100 nm. The mechanical properties of composites are effectively improved with the addition of nanoparticles. Thermal aging property of NR are also improved with the addition of nanoparticles. The best process is emulsion coagulation method.

  13. Comparative study of Palladium (II using 4-Hydroxy 3, 5 dimethoxy benzaldehyde 4-hydroxy benzoyl hydrazone and Cinnamaldehyde 4-hydroxy benzoylhydrazone in presence of micellar medium by Spectrophotometry

    Directory of Open Access Journals (Sweden)

    D.Gopala Krishna,

    2010-09-01

    Full Text Available Two simple, sensitive, rapid and selective spectrophotometric methods have been developed for the determination of Palladium (II using newly synthesized reagents 4-Hdroxy3,5dimethoxy benzaldehyde-4-hydroxybenzoylhydrazone (HDMBHBH and Cinnamaldehyde 4-hydroxy benzoylhydrazone (CMHBH in presence of neutral surfactant TritonX-100-5% (micellar medium. Palladium (II forms a brown coluored water-soluble complex with HDMBHBH and CMHBH-in the pH range 1.0-6.0. The Pd (II-HDMBHBH complex shows maximum absorbance at max 373 nm in the pH range 3.0-4.0 and Pd (II-CMHBH shows at max 375 nm in thepH range 4.0-5.0. At these wavelengths (max, the complex shows maximum absorbance while the reagent blanks shows negligible absorbance. Hence, analytical studies were carried out at max 373 nm at pH 3.0 for HDMBHBH and 375 nm at pH 4.0 for CMHBH against reagent blanks. Beer's law is obeyed in the range 0.106-1.064 μg ml-1 and the optimum concentration range from ringbom plot is 0.212-0.957 g/ml of Palladium (II for both reagents. The molar absorptivity and Sandell's sensitivity for the coloured solution were found to be 7.5 x 104 L mol-1 cm-1 and 0.0015-μg. cm-2 for HDMBHBH, 6.0x104L mol-1 cm-1 , and 0.0017 -μg. cm-2 for CMHBH respectively. The interference effects of various diverse ions have been studied. Palladium (II forms 1:1 complex with HDMBHBH and CMHBH stoichiometry with stability constant 7.29 x 106 for HDMBHBH and 3.55 x 106 for CMHBH. The standard deviation in the determination of 0.638-μg ml-1 of Palladium (II is 0.003 for HDMBHBH and 0.008 for CMHBH. The Relative standard deviation is 0.71% for HDMBHBH and 2.5% for CMHBH. First and second order derivative spectroscopic methods were developed at max 422 nm and 444 nm for HDMBHBH and at 402 nm and438 nm for CMHBH respectively, for the determination of Palladium (II, which is more sensitive than the zero order method. The developed method has been employed for the determination of

  14. Synthesis, spectral and antimicrobial activity of Zn(II) complexes with Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and benzaldehyde/2-hydroxyacetophenone/indoline-2,3-dione.

    Science.gov (United States)

    Singh, Ajay K; Pandey, O P; Sengupta, S K

    2013-09-01

    Zn(II) complexes have been synthesized by reacting zinc acetate with Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and 2-hydroxyacetophenone/benzaldehyde/indoline-2,3-dione. All these complexes are soluble in DMF and DMSO; low molar conductance values indicate that they are non electrolytes. Elemental analyses suggest that the complexes have 1:2 metal to ligands stoichiometry of the types [ZnL2(H2O)2](L=monoanionic Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and 2-hydroxyacetophenone/indoline-2,3-dione) [ZnL2(')(OOCCH3)2(H2O)2](L'=neutral Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and benzaldehyde), and they were characterized by IR, (1)H NMR, and (13)C NMR. Particle sizes of synthesized compounds were measured with dynamic light scattering (DLS) analyser which indicates that particle diameter are of the range ca. 100-200nm. All these Schiff bases and their complexes have also been screened for their antibacterial (Bacillus subtilis (B. subtilis), Escherichia coli (E. coli) and antifungal activities (Colletotrichum falcatum (C. falcatum), Aspergillus niger (A. niger), Fusarium oxysporium (F. oxysporium) Curvularia pallescence (C. pallescence). The antimicrobial activities have shown that upon complexation the activity increases.

  15. Ozone reaction with n-aldehydes (n=4-10), benzaldehyde, ethanol, isopropanol, and n-propanol adsorbed on a dual-bed graphitized carbon-carbon molecular sieve adsorbent cartridge.

    Science.gov (United States)

    McClenny, W A; Colón, M; Oliver, K D

    2001-09-21

    Ozone reacts with n-aldehydes (n=4-10), benzaldehyde, ethanol, isopropanol and n-propanol adsorbed on a dual-bed graphitized carbon-carbon molecular sieve adsorbent cartridge. Destruction of n-aldehydes increases with n number and with ozone concentration. In some sampling experiments both generation and destruction of n-aldehydes by ozone are observed. In field experiments the results of sample analysis for n-aldehydes and benzaldehyde are frequently not proportional to sample volume whereas results for toluene and isoprene, and sometimes for total carbon, are. A simple theory is developed to simulate the net result of three processes: the adsorption of compounds from an air stream onto a solid adsorbent, the generation of compounds by reaction of ozone with materials upstream of or on the adsorbent, and the destruction by ozone of pre-existing compounds and compounds adsorbed from the sample stream. The use of distributed volume pairs is recommended as a way to identify loss of sample integrity during air monitoring experiments.

  16. Determination of human serum semicarbazide-sensitive amine oxidase activity via flow injection analysis with fluorescence detection after online derivatization of the enzymatically produced benzaldehyde with 1,2-diaminoanthraquinone.

    Science.gov (United States)

    El-Maghrabey, Mahmoud H; Kishikawa, Naoya; Ohyama, Kaname; Imazato, Takahiro; Ueki, Yukitaka; Kuroda, Naotaka

    2015-06-30

    A fast, simple, and sensitive flow injection analysis method was developed for the measurement of semicarbazide-sensitive amine oxidase (SSAO) activity in human serum. Benzaldehyde, generated by the action of SSAO after incubation of serum with benzylamine, was derivatized with a novel aromatic aldehyde-specific reagent (1,2-diaminoanthraquinone) and the fluorescent product was measured by fluorescence detection at excitation and emission wavelengths of 390 and 570nm, respectively. Serum SSAO activity was defined as benzaldehyde (nmol) formed per milliliter serum per hour. The method was linear over SSAO activity of 0.2-150.0nmolmL(-1)h(-1) with a detection limit of 0.06nmolmL(-1)h(-1). The %RSD of intra-day and inter-day precision did not exceed 9.4% and the accuracy ranged from -6.5 to -0.6%. The method was applied for the determination of the serum SSAO activity in healthy controls (C, n=24) and diabetes mellitus patients (DM, n=18). It was demonstrated that the activity (mean±SE) of SSAO in diabetics sera was significantly higher than that in healthy subjects' ones (DM; 73.3±1.8nmolmL(-1)h(-1)vs C; 58.9±2.2nmolmL(-1)h(-1), P<0.01).

  17. Synthesis, spectral and antimicrobial activity of Zn(II) complexes with Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and benzaldehyde/2-hydroxyacetophenone/indoline-2,3-dione

    Science.gov (United States)

    Singh, Ajay K.; Pandey, O. P.; Sengupta, S. K.

    2013-09-01

    Zn(II) complexes have been synthesized by reacting zinc acetate with Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and 2-hydroxyacetophenone/benzaldehyde/indoline-2,3-dione. All these complexes are soluble in DMF and DMSO; low molar conductance values indicate that they are non electrolytes. Elemental analyses suggest that the complexes have 1:2 metal to ligands stoichiometry of the types [ZnL2(H2O)2](L = monoanionic Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and 2-hydroxyacetophenone/indoline-2,3-dione) [ZnL2‧(OOCCH3)2(H2O)2](L‧ = neutral Schiff bases derived from 2-hydrazino-5-[substituted phenyl]-1,3,4-thiadiazole and benzaldehyde), and they were characterized by IR, 1H NMR, and 13C NMR. Particle sizes of synthesized compounds were measured with dynamic light scattering (DLS) analyser which indicates that particle diameter are of the range ca. 100-200 nm. All these Schiff bases and their complexes have also been screened for their antibacterial (Bacillus subtilis (B. subtilis), Escherichia coli (E. coli) and antifungal activities (Colletotrichum falcatum (C. falcatum), Aspergillus niger (A. niger), Fusarium oxysporium (F. oxysporium) Curvularia pallescence (C. pallescence). The antimicrobial activities have shown that upon complexation the activity increases.

  18. The DFT study on the reaction between benzaldehyde and 4-amine-4H-1,2,4-triazole and their derivatives as a source of stable hemiaminals and Schiff bases. Effect of substitution and solvation on the reaction mechanism.

    Science.gov (United States)

    Berski, Slawomir; Gordon, Agnieszka J; Ciunik, Leszek Zbigniew

    2015-03-01

    Reaction mechanism for the benzaldehyde (ald) and 4-amine-4H-1,2,4-triazole (4at) has been investigated at the DFT (B3LYP)/6-31+G(d) computational level. Three transition states (TS) have been identified. The TS1 corresponds to hydrogen transfer from the NH2 group to the C = O bond and nucleophillic attack of the carbon atom from the aldehyde group on the nitrogen atom from the NH2 group in 4at. The result of this reaction is the hemiaminal molecule. The TS2 characterises an internal rearrangement of the benzene and triazole rings in the hemiaminal molecule. The TS3 leads to breaking of the O-H bond, the elimination reaction of the H2O molecule, and formation of the C=N bond. The final product of this reaction is a Schiff base. In order to determine the most favorable conditions for hemiaminal formation, the influence of electronic structure modification on the energetic properties during the reaction of benzaldehyde and 4-amine-4H-1,2,4-triazole has been studied. Thirteen substituents: NH2, OH, OCH3, CH3, F, I, Cl, Br, COH, COOH, CF3, CN, NO2, with different Hammett's constant values (σ = -0.66-+0.78) have been considered. Finally, the reaction mechanism has been investigated in the presence of 1 to 5 water molecules.

  19. Preparation, characterization and catalytic properties of MCM-48 supported tungstophosphoric acid mesoporous materials for green synthesis of benzoic acid

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Hai-Yan; Zhang, Xiao-Li; Chen, Xi; Chen, Ya; Zheng, Xiu-Cheng, E-mail: zhxch@zzu.edu.cn

    2014-03-15

    MCM-48 and tungstophosphoric acid (HPW) were prepared and applied for the synthesis of HPW/MCM-48 mesoporous materials. The characterization results showed that HPW/MCM-48 obtained retained the typical mesopore structure of MCM-48, and the textural parameters decreased with the increase loading of HPW. The catalytic oxidation results of benzyl alcohol and benzaldehyde with 30% H{sub 2}O{sub 2} indicated that HPW/MCM-48 was an efficient catalyst for the green synthesis of benzoic acid. Furthermore, 35 wt% HPW/MCM-48 sample showed the highest activity under the reaction conditions. Highlights: • 5–45 wt% HPW/MCM-48 mesoporous catalysts were prepared and characterized. • Their catalytic activities for the green synthesis of benzoic acid were investigated. • HPW/MCM-48 was approved to be an efficient catalyst. • 5 wt% HPW/MCM-48 exhibited the highest catalytic activity.

  20. Sodium Hydrogen Sulfate as Effective and Reusable Heterogeneous Catalyst for the One-pot Preparation of 14H-[(Un)substituted phenyl]-dibenzo[a,j]xanthene Leuco-dye Derivatives

    Institute of Scientific and Technical Information of China (English)

    SHATERIAN Hamid Reza; DOOSTMOHAMMADI Razieh; GHASHANG Majid

    2008-01-01

    NaHSO4·H2O has been used as an efficient catalyst for the one-pot preparation of 14H-[(un)substituted phenyl]-dibenzo[a,j]xanthene leuco-dye derivatives by condensation of β-naphthol with substituted benzaldehydes under microwave and thermal conditions.This method has the advantages of high yields,a green reaction,an efficient and cost-effective method,simple procedures,short reaction time,and easy workup.

  1. SBA-15负载的Cu(II)席夫碱配合物催化的苯乙烯氧化反应制备苯甲醛%Catalytic oxidation of styrene to benzaldehyde over a copper Schiff-base/SBA-15 catalyst

    Institute of Scientific and Technical Information of China (English)

    朱学成; 沈如伟; 张利雄

    2014-01-01

    The amino-modified mesoporous material SBA-15 (NH2-SBA-15) was prepared via co-condensation of tetraethylorthosilicate with 3-aminopropyltriethoxysilane in the presence of an amphiphilic triblock copolymer as a pore-directing agent under acidic conditions. The SBA-15-supported Cu Schiff-base complex (Cu-SBA-15) was then synthesized by condensation of salicylaldehyde with NH2-SBA-15, followed by the addition of a solution of Cu(NO3)2. The supported complex was sys-tematically characterized by elemental analysis, inductive coupled high frequency plasma atomic emission spectrometry, powder X-ray diffraction, Fourier transform infrared spectroscopy, ultravi-olet-visible spectroscopy, field scanning electron microscopy, transmission electron microscopy, N2 absorption-desorption, and thermo gravimetric analysis, and was used as the catalyst for the selec-tive oxidation of styrene to benzaldehyde. The influence of the reaction parameters was assessed. The maximum conversion of styrene was 84.4%and the selectivity for benzaldehyde was 83.9%, when the reaction was conducted with a 2:1 molar ratio of H2O2:styrene in the presence of 3.8 wt%catalyst at 100 °C for 8 h. The TOF was 261.1 h-1, and the catalyst could be used three times without significant loss of activity. The uniformly sized pore channels, high specific surface area, and well-distributed active centers of the catalyst may contribute to the high activity.%子筛SBA-15(NH2-SBA-15),再利用其中氨基与水杨醛的缩合反应制备SBA-15固载的席夫碱,该席夫碱与Cu(NO3)2溶液反应最终制成固定于SBA-15的Cu(II)席夫碱配合物多相催化剂Cu-SBA-15.采用X射线衍射、红外光谱仪、紫外可见分光光度计、场发射电镜、透射电镜、N2吸附-脱附、元素分析、原子发射光谱和热重分析对催化剂进行了表征,并将此催化剂用于无有机溶剂条件下催化氧化苯乙烯制备苯甲醛,考察了反应时间、反应温度、H2O2用量、水的用量

  2. Difluoromethane preparation

    NARCIS (Netherlands)

    Wiersma, A.; Sandt, E.J.A.; Van Bekkum, H.; Makkee, M.; Moulijn, J.A.

    1996-01-01

    Abstract of NL 9401574 (A) The invention relates to a method for preparing difluoromethane, wherein dichlorodifluoromethane or monochlorodifluoromethane is brought into contact with hydrogen in the presence of palladium on activated carbon, wherein the loading of the palladium on the activated c

  3. Influences of glycerol concentration on properties of natural pure cellulose membrane prepared by NMMO technology%甘油含量对NMMO工艺天然纯纤维素膜性能的影响

    Institute of Scientific and Technical Information of China (English)

    李冬娜; 马晓军; 王晓敏; 乔华

    2012-01-01

    以棉纤维素为原料,以NMMO(N-甲基吗啉-N-氧化物)为溶剂,以甘油为增塑剂制取天然纯纤维素包装膜,研究了不同甘油含量对纤维素膜性能的影响。结果表明,随着甘油含量的增加,纤维素膜的断裂伸长率随之增加,拉伸强度随之降低,二者变化幅度都很大;当甘油含量从2%增加到5%,纤维素膜的透油系数增加了13.4%,氧气透过率增加了3.0%,透湿系数增加了16.7%,透光率增加了22.4%,横向热收缩率增加了58.8%,纵向热收缩率增加了54.7%。可见,甘油含量对膜的透氧性影响较为微弱,但对力学性能、透油性、透湿性、透明度、热收缩率影响均较为显著。%Natural pure cellulose packaging films were prepared by means of the dissolution of cotton cellulose in NMMO and glycerol was used as plasticizer,the effects of different glycerol concentration on properties were studied,the results showed that elongation at break increase,but the tensile strength decrease with the increasing of glycerol concentration,and both change significantly;when the content increased from 2% to 5%,the oil transmission,oxygen permeation flux,water vapor permeability,the light transmittance,the transverse and longitudinal direction hot shrinkage rate increased by 13.4%,3.0%,16.7%,22.4%,58.8%,54.7%,respectively.It's clear that glycerol concentration had weak influence on oxygen permeation,but the mechanical properties,the oil permeability,the water vapor permeability,the transparency and hot shrinkage rate changed significantly.

  4. Relief Preparation Plan for Natural Disasters: a Stochastic Programming Model and Case%面向自然灾害的救援准备计划:随机规划模型与案例

    Institute of Scientific and Technical Information of China (English)

    秦绪伟; 刘晓; 李凯

    2012-01-01

    在自然灾害频发区预置足够的救援设施和物资是灾后有效执行救援行动的基石.在有限救灾预算下,提出一个以最小化灾民伤亡期望人数为目标的两层随机规划模型.上层为灾前战略性决策,包括医院和临时安置点的能力扩展、储备库选址、物资储备量和各类车辆能力配置;下层为各灾难情景的应急作业性决策,包括伤员从灾难点到医院的转移、灾民从灾难点到安置点的运送、医疗物资从储备库到医院的补给和生活物资从储备库到安置点的配送.最后说明性案例验证救援准备计划随机模型的有效性.%The relief preparation of adequate facilities and resources in areas frequently struck by natural disasters is a cornerstone that guarantees the effective execution of relief operations. Within a limited budget, a two-stage stochastic programming model is developed with an aim to minimizing the expected number of casualties. The first stage of the model is focused on pre- disaster strategic decisions including the expansion of hospitals and shelters, the site selection of warehouses, the allocation of emergency supplies and relief vehicles, and the second stage is concerned with operational decisions on emergency logistics plans, including taking the wounded from disaster areas to hospitals, transferring the victims from disaster areas to shelters, sending the medical supplies from warehouses to hospitals and shelters, and dispatching the living materials from warehouses to resettlement areas. The computational results of an illustrative case prove the validity of the proposed stochastic optimization model.

  5. Optimization of Preparation Process for Natural Nutritional Jelly Sweets with Lingnan Flavor%岭南风味天然保健型凝胶软糖工艺优化

    Institute of Scientific and Technical Information of China (English)

    陈洋泰; 张织芬; 樊亚鸣; 曹少梅; 赵佩颖; 陈立显; 畅乐

    2011-01-01

    研究一种具有岭南风味的天然保健型凝胶软糖。通过明胶与果胶的复配,获得较好的凝胶性能及较高的融点;添加具有岭南特色风味的陈皮、春砂仁油树脂和黄皮果肉泥,获得独特的风味和外观;利用不同亲水亲油平衡值的乳化剂蔗糖酯,解决制作过程中的起泡性、透明度和黏壁性的问题。最佳配方为:明胶与果胶添加量为固体总质量的2.3%和1.3%;陈皮、砂仁油树脂和黄皮果肉泥的添加量为0.77%、0.39%和5.8%;蔗糖酯s170、s1570的添加量为0.08%和0.19%。通过一定的制作工艺研制出具有高融点、风味独特、弹性与韧性适中、外观晶莹剔透的凝胶软糖。%In this paper,a kind of natural nutritional jelly sweets with Lingnan flavor was studied.First,gelatin and pectin were mixed to achieve better gel performance and higher gel melting point;then Pericarpium citri reticulatae oleoresin,Amomum villosum oleoresin and wampee pulp sludge with Lingnan flavor were added to obtain unique flavor and appearance;in addition,emulsifiers such as sucrose ester with different HLB values were used to resolve the problems related to foaming,transparency and wall stickiness.The optimal formula wascomposed of 2.3% gelatin,1.3% pectin,0.77% Pericarpium citri reticulatae oleoresin,0.39% Amomum villosum oleoresin,5.8% wampee pulp sludge,0.08% sucrose ester s170 and 0.19% sucrose ester s1570.The jelly candy prepared using this formula revealed high melting point,unique flavor,moderate elasticity and flexibility and crystal clear appearance.

  6. The Nature of Atoms.

    Science.gov (United States)

    Holden, Alan

    This monograph was written for the purpose of presenting physics to college students who are not preparing for careers in physics. It deals with the nature of atoms, and treats the following topics: (1) the atomic hypothesis, (2) the chemical elements, (3) models of an atom, (4) a particle in a one-dimensional well, (5) a particle in a central…

  7. How Prepared is Prepared Enough?

    Science.gov (United States)

    Porter-Levy; Macleod; Rickert

    1996-10-01

    A 17-year-old female was in the final stage in treatment of right unilateral cleft lip and palate. She had undergone a number of previous surgeries. Hearing and speech were good on evaluation, and her social and family situation were deemed excellent. After preparatory orthodontics she underwent a Lefort I maxillary advancement. Surgery was successful and she was admitted into postoperative recovery. However, the lack of adequate preoperative preparation caused traumatic reaction from the patient and her parents: anxiety over appearance, crying, refusal of oral fluids and oral care, refusal of analgesia, and refusal to mobilize. The patience and persistence of hospital staff slowly overcame all adversities and the patient moved on to full and successful recovery, but this case prompted changes in preoperative procedures and involvement of patients and their families in postoperative meal selection, planing, and preparation.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-02-15

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

  9. 对甲基苯甲醛改性煤沥青的改性机理研究%STUDY ON MODIFITION MECHANISM OF THE MODIFIED COAL TAR PITCH WITH 4-METHYL BENZALDEHYDE

    Institute of Scientific and Technical Information of China (English)

    宋士华; 魏健宁; 马明亮

    2007-01-01

    以对甲基苯甲醛(4-methyl benzaldehyde,简称4-MB)为改性剂,在对甲苯磺酸(PTS)的作用下对煤沥青(Coal Tar Pitch)进行了改性研究.采用傅立叶红外光谱(FT-IR)和核磁共振氢谱(1H-NMR)对煤沥青改性机理进行分析;采用扫描电镜(SEM)观察改性后煤沥青的形貌;采用光学显微镜观察改性沥青热解产物的光学结构.实验结果表明,对甲基苯甲醛在酸性催化剂的催化作用下与煤沥青发生亲电取代反应.

  10. Computational studies of ion pairing. 8. Ion pairing of tetraalkylammonium ions to nitrosobenzene and benzaldehyde redox species. A general binding motif for the interaction of tetraalkylammonium ions with benzenoid species.

    Science.gov (United States)

    Fry, Albert J

    2013-06-01

    Very little data is available on the detailed structures of ion pairs in solution, since few general experimental methods are available for obtaining such information. For this reason, computational methods have emerged as the method of choice for determining the structures of organic ion pairs in solution. The present study examines the ion pairs between a series of tetraalkylammonium ions and several redox forms of nitrosobenzene and a series of substituted benzaldehydes. The structures, though previously unexpected, are chemically reasonable and fit into a previous pattern of ion pairing described in previous publications in this series. To date in these studies, a total of 73 ion pairs and related species have in fact been identified having exactly the same unusual orientation of the tetraalkylammonium component with respect to the donor species. The results are pertinent to topics of general current interest, including self-assembly, molecular recognition, and supramolecular assembly.

  11. Inhibitory Effects of Benzaldehyde Derivatives from the Marine Fungus Eurotium sp. SF-5989 on Inflammatory Mediators via the Induction of Heme Oxygenase-1 in Lipopolysaccharide-Stimulated RAW264.7 Macrophages

    Directory of Open Access Journals (Sweden)

    Kyoung-Su Kim

    2014-12-01

    Full Text Available Two benzaldehyde derivatives, flavoglaucin (1 and isotetrahydro-auroglaucin (2, were isolated from the marine fungus Eurotium sp. SF-5989 through bioassay- and 1H NMR-guided investigation. In this study, we evaluated the anti-inflammatory effects of these compounds in lipopolysaccharide (LPS-stimulated RAW264.7 macrophages. We demonstrated that compounds 1 and 2 markedly inhibited LPS-induced nitric oxide (NO and prostaglandin E2 (PGE2 production by suppressing inducible nitric oxide synthase (iNOS and cyclooxygenase-2 (COX-2 protein expression without affecting cell viability. We also demonstrated that the compounds reduced the secretion of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α, interleukin-1β (IL-1β and interleukin-6 (IL-6. Furthermore, compounds 1 and 2 inhibited LPS-induced nuclear factor-κB (NF-κB activation by suppressing phosphorylation of IkappaB (IκB. These results indicated that the anti-inflammatory effects of these benzaldehyde derivatives in LPS-stimulated RAW264.7 macrophages were due to the inactivation of the NF-κB pathway. In addition, compounds 1 and 2 induced heme oxygenase-1 (HO-1 expression through the nuclear transcription factor-E2–related factor 2 (Nrf2 translocation. The inhibitory effects of compounds 1 and 2 on the production of pro-inflammatory mediators and on NF-κB binding activity were reversed by HO-1 inhibitor tin protoporphyrin (SnPP. Thus, the anti-inflammatory effects of compounds 1 and 2 also correlated with their ability of inducing HO-1 expression.

  12. Inhibitory effects of benzaldehyde derivatives from the marine fungus Eurotium sp. SF-5989 on inflammatory mediators via the induction of heme oxygenase-1 in lipopolysaccharide-stimulated RAW264.7 macrophages.

    Science.gov (United States)

    Kim, Kyoung-Su; Cui, Xiang; Lee, Dong-Sung; Ko, Wonmin; Sohn, Jae Hak; Yim, Joung Han; An, Ren-Bo; Kim, Youn-Chul; Oh, Hyuncheol

    2014-12-19

    Two benzaldehyde derivatives, flavoglaucin (1) and isotetrahydro-auroglaucin (2), were isolated from the marine fungus Eurotium sp. SF-5989 through bioassay- and 1H NMR-guided investigation. In this study, we evaluated the anti-inflammatory effects of these compounds in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. We demonstrated that compounds 1 and 2 markedly inhibited LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production by suppressing inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression without affecting cell viability. We also demonstrated that the compounds reduced the secretion of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). Furthermore, compounds 1 and 2 inhibited LPS-induced nuclear factor-κB (NF-κB) activation by suppressing phosphorylation of IkappaB (IκB). These results indicated that the anti-inflammatory effects of these benzaldehyde derivatives in LPS-stimulated RAW264.7 macrophages were due to the inactivation of the NF-κB pathway. In addition, compounds 1 and 2 induced heme oxygenase-1 (HO-1) expression through the nuclear transcription factor-E2-related factor 2 (Nrf2) translocation. The inhibitory effects of compounds 1 and 2 on the production of pro-inflammatory mediators and on NF-κB binding activity were reversed by HO-1 inhibitor tin protoporphyrin (SnPP). Thus, the anti-inflammatory effects of compounds 1 and 2 also correlated with their ability of inducing HO-1 expression.

  13. Natural Gas Energy Educational Kit.

    Science.gov (United States)

    American Gas Association, Arlington, VA. Educational Services.

    Prepared by energy experts and educators to introduce middle school and high school students to natural gas and its role in our society, this kit is designed to be incorporated into existing science and social studies curricula. The materials and activities focus on the origin, discovery, production, delivery, and use of natural gas. The role of…

  14. Displaying Nature

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Beijing Museum of Natural History is located in Chongwen District, close to the Temple of Heaven and Tianqiao Theater. It was founded in 1951 and formally named Beijing Museum of Natural History in 1962.

  15. Natural gas monthly, August 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-08-25

    The Natural Gas Monthly (NGM) is prepared in the Data Operations Branch of the Reserves and Natural Gas Division, Office of Oil and Gas, Energy Information Administration (EIA), US Department of Energy (DOE). The NGM highhghts activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information.

  16. Natural gas monthly, October 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    The Natural Gas Monthly (NGM) is prepared in the Data Operations Branch of the Reserves and Natural Gas Division, Office of Oil and Gas, Energy Information Administration (EIA), U.S. Department of Energy (DOE). The NGM highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information.

  17. Antimicrobial Activity and Urease Inhibition of Schiff Bases Derived from Isoniazid and Fluorinated Benzaldehydes and of Their Copper(II Complexes

    Directory of Open Access Journals (Sweden)

    Ladislav Habala

    2016-12-01

    Full Text Available In order to evaluate the influence of substitution on biological properties of Schiff bases and their metal complexes, a series of differently substituted fluorine-containing Schiff bases starting from the drug isoniazid (isonicotinylhydrazide were prepared and their structures were established by single-crystal X-ray diffraction. Also, four copper(II complexes of these Schiff bases were synthesized. The prepared compounds were evaluated for their antimicrobial activity and urease inhibition. Two of the Schiff bases exerted activity against C. albicans. All copper(II complexes showed excellent inhibitory properties against jack bean urease, considerably better than that of the standard inhibitor acetohydroxamic acid.

  18. Antimicrobial Activity and Urease Inhibition of Schiff Bases Derived from Isoniazid and Fluorinated Benzaldehydes and of Their Copper(II) Complexes.

    Science.gov (United States)

    Habala, Ladislav; Varényi, Samuel; Bilková, Andrea; Herich, Peter; Valentová, Jindra; Kožíšek, Jozef; Devínsky, Ferdinand

    2016-12-17

    In order to evaluate the influence of substitution on biological properties of Schiff bases and their metal complexes, a series of differently substituted fluorine-containing Schiff bases starting from the drug isoniazid (isonicotinylhydrazide) were prepared and their structures were established by single-crystal X-ray diffraction. Also, four copper(II) complexes of these Schiff bases were synthesized. The prepared compounds were evaluated for their antimicrobial activity and urease inhibition. Two of the Schiff bases exerted activity against C. albicans. All copper(II) complexes showed excellent inhibitory properties against jack bean urease, considerably better than that of the standard inhibitor acetohydroxamic acid.

  19. Preparation on pitch-based carbon coated natural graphite as an anode material for lithium-ion batteries%沥青炭涂覆天然石墨用作锂离子电池负极材料的研究

    Institute of Scientific and Technical Information of China (English)

    王茜; 柯昌美; 崔正威; 从野; 董志军; 袁观明; 李轩科

    2014-01-01

    将改质沥青浆料与球形天然石墨粉末混合,然后在氩气气氛保护下经过不同温度热处理制备沥青炭涂覆天然石墨负极材料。利用X射线衍射(XRD)、电镜扫描(SEM)、偏光显微镜(PLM)及充放电测试等分析测试技术对所制得材料的结构、形貌和电化学性能进行了表征。结果表明,沥青涂覆处理后石墨材料的电化学性能得到显著改善,经950°C热处理的11%的沥青涂覆改性的天然石墨负极材料具有更高的可逆容量和更好的循环性能。%The pitch-based carbon coated spherical natural graphite particles, as an anode material for lithium-ion battery, were prepared by mixing a modified pitch grout with spherical natural graphite particles and subsequent heat-treatment at various temper-atures. The structure and properties of the prepared products were characterized by X-ray diffraction, scanning electron microscopy, polarized light microscopy and electrochemical performance tests. The results show that the electrochemical performance of pitch-coated natural graphite is improved significantly. After 950 °C heat-treatment, the spherical natural graphite particles coated by 11%pitch possess much higher reversible capacity and rate property than those of spherical natural graphite.

  20. The study of partial and excess molar volumes for binary mixtures of nitrobenzene and benzaldehyde with xylene isomers from T = (298.15 to 318.15 K and P = 0.087 MPa

    Directory of Open Access Journals (Sweden)

    Hamid R. Rafiee

    2016-09-01

    Full Text Available Based on density measurements, partial and excess molar volumes for binary mixtures of nitrobenzene and benzaldehyde with three isomers of xylene have been measured. The whole range of composition and temperatures from T = (298.15 to 318.15 K at ambient pressure 0.087 MPa, has been considered. The excess molar volumes were negative and decreased by increasing temperature for all mixtures which are explained based on intermolecular interactions. Excess molar volumes for solutions including nitrobenzene were absolutely larger than benzaldehyde binary mixtures. The partial and excess molar volumes for each component have been appraised and reported. The excess molar volumes have been successfully fitted to Redlich–Kister equation.

  1. Preparation of manganese oxide immobilized on SBA-15 by atomic layer deposition as an efficient and reusable catalyst for selective oxidation of benzyl alcohol in the liquid phase

    Energy Technology Data Exchange (ETDEWEB)

    Mahdavi, Vahid, E-mail: v-mahdavi@araku.ac.ir; Mardani, Mahdieh

    2015-04-01

    Manganese oxide supported on mesoporous silica SBA-15 catalyst (Mn-SBA-15) was tested with Mn contents in the range of 0.8–23 wt%. Samples were prepared by the controlled grafting process of atomic layer deposition (ALD). Other sample was prepared for comparisons by the wet impregnation method. These samples were characterized by the techniques of ICP, XRD, SEM, Raman, FT-IR spectroscopy, diffuse reflectance UV–Vis, TGA-DSC, and N{sub 2} absorption–desorption surface area measurement. Results indicated that anchored manganese oxide particles have been successfully synthesized over the surface of SBA-15. These samples contained Red-Ox ion pairs of Mn{sup 2+} and Mn{sup 3+} highly dispersed on the mesoporous silica surface. The impregnated sample exhibited lower surface area and contained Red-Ox ion pairs of Mn{sup 3+} and Mn{sup 4+} more aggregated particles on the SBA-15 surface. Results determined Mn-SBA-15 as an efficient and selective catalyst for oxidation of benzyl alcohol with tert-butylhydroperoxide in liquid phase. In accordance with expectations, there was a negligible amount of leaching of immobilized manganese oxide from the support during the reaction, because of strong surface interaction between manganese oxide and hydroxyls groups. The influences of reaction temperature, reaction time, solvent, TBHP/benzyl alcohol molar ratio, amount of catalyst and reusability were investigated. Under optimized conditions (0.2 g catalyst, TBHP/benzyl alcohol molar ratio 1, solvent acetonitrile; T = 90 °C; reaction time 8 h), results achieved 70% conversion of benzyl alcohol and 100% selectivity to benzaldehyde. - Highlights: • Manganese oxide immobilized on SBA-15 were prepared by atomic layer deposition (ALD). • Oxidation of benzyl alcohol to benzaldehyde over this catalyst were investigated. • Effects of loading of manganese oxide, T, oxidant/alcohol ratio were investigated. • The leaching of manganese oxide from support during the reaction was

  2. PLURALIZING NATURE

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel

    2014-01-01

    Denmark is widely recognised for its democratic approach to planning and the idea of planning for the common good. This interest in the common good and common values seems also to be reflected in the way which nature restoration is planned and managed – one common nature directed by the public...... authorities. But nature restoration is far from being a neural undertaking. Just like any other type of heritage production it can be the source of dissonance – ‘our’ nature is not necessary ‘their’ nature. Often this dissonance is managed in ways, which are not particular sensitive to site......-specificity. As exemplified by the Skjern River Restoration Project (1999-2003), one interpretation of the landscape sometimes suppresses other valid interpretations neglecting its diverse history. However, evidence from Switzerland suggests that planning for the common good, in the case of nature restoration, does...

  3. A stereodivergent strategy for the preparation of corynantheine and ipecac alkaloids, their epimers, and analogues: efficient total synthesis of (-)-dihydrocorynantheol, (-)-corynantheol, (-)-protoemetinol, (-)-corynantheal, (-)-protoemetine, and related natural and nonnatural compounds.

    Science.gov (United States)

    Zhang, Wei; Bah, Juho; Wohlfarth, Andreas; Franzén, Johan

    2011-12-01

    Here we present a general and common catalytic asymmetric strategy for the total and formal synthesis of a broad number of optically active natural products from the corynantheine and ipecac alkaloid families, for example, indolo[2,3-a]- and benzo[a]quinolizidines. Construction of the core alkaloid skeletons with the correct absolute and relative stereochemistry relies on an enantioselective and diastereodivergent one-pot cascade sequence followed by an additional diastereodivergent reaction step. This allows for enantio- and diastereoselective synthesis of three out of four possible epimers of the quinolizidine alkaloids that begin from common and easily accessible starting materials by using a common synthetic route. Focus has been made on excluding protecting groups and limiting isolation and purification of synthetic intermediates. This methodology is applied in the total synthesis of the natural products (-)-dihydrocorynantheol, (-)-hirsutinol, (-)-corynantheol, (-)-protometinol, (-)-dihydrocorynantheal, (-)-corynantheal, (-)-protoemetine, (-)-(15S)-hydroxydihydrocorynantheol, and an array of their nonnatural epimers. The potential of this strategy is also demonstrated in the synthesis of biologically interesting natural product analogues not accessible through synthetic elaboration of alkaloid precursors available from nature, for example, thieno[3,2-a]quinolizidine derivatives. We also report the formal synthesis of (+)-dihydrocorynantheine, (-)-emetine, (-)-cephaeline, (-)-tubulosine, and (-)-deoxytubulosine.

  4. Nature seconded

    OpenAIRE

    Gough, Tim

    2002-01-01

    Heidegger�s remark that the banks of the river (representing nature in its supposedly pure state) only become apparent because of the presence of the bridge (representing the artificial in its supposed opposition to that nature) will lead this presentation to a discussion of whether or not the idea of �nature� as prior to architecture remains unequivocally valid. If nature/the site - that which claims to come before the artificial/architecture - only appears as a result of the presence ...

  5. Laboratory evaluation of commercial interferon preparations

    Energy Technology Data Exchange (ETDEWEB)

    Schoub, B.D.; Lyons, S.F.; Crespi, M.; Chiu, M.N. (University of the Witwatersrand, Johannesburg (South Africa). Dept. of Virology); Lomnitzer, R. (University of the Witwatersrand, Johannesburg (South Africa). Dept. of Immunology)

    1983-01-08

    The antiviral, antiproliferative and natural killer-cell (NKC) stimulatory activities of four commercial therapeutic interferon preparations were assayed in a laboratory. The antiviral and antiproliferative activities of each preparation were relatively similar, but an unexpectedly high NKC stimulatory activity was found in one of them. In-house determination of antiviral activity and evaluation of the antiproliferative and NKC stimulation potential of interferon preparations are essential before rational clinical trials of this agent are carried out.

  6. The Preparation of Human Service Professionals.

    Science.gov (United States)

    Gartner, Alan

    New forms of preparing workers in the human services have the potential of changing and improving those services. A central feature of the new forms of preparation is that they must both be preparatory for the services and be characteristic of them (for example, if the services are participatory in nature, the training should also be so). There is…

  7. β-环糊精微反应器中苯甲醇氧化制备苯甲醛%Preparation of Benzaldehyde Through Oxidation of Benzyl Alcohol in Microreactor of β-Cyclodextrin

    Institute of Scientific and Technical Information of China (English)

    于红杰; 兰支利; 尹笃林; 欧建雄

    2008-01-01

    以β-环糊精为微反应器,用NBS作为氧化剂,能有效进行催化苯甲醇氧化制备苯甲醛.实验结果表明,β-环糊精微反应器中一锅法合成苯甲醛,具有反应条件温和、无环境污染、操作简单、用水作为溶剂、环糊精可以循环使用等优点.在反应温度为25℃,反应时间为10 h,β-环糊精、苯甲醇、NBS的摩尔比为2:1:2时,苯甲醛的产率可达83.7%.

  8. Electronic and vibrational spectra of protonated benzaldehyde-water clusters, [BZ-(H2O)n≤5]H+: evidence for ground-state proton transfer to solvent for n ≥ 3.

    Science.gov (United States)

    Dopfer, Otto; Patzer, Alexander; Chakraborty, Shamik; Alata, Ivan; Omidyan, Reza; Broquier, Michel; Dedonder, Claude; Jouvet, Christophe

    2014-03-28

    Vibrational and electronic photodissociation spectra of mass-selected protonated benzaldehyde-(water)n clusters, [BZ-(H2O)n]H(+) with n ≤ 5, are analyzed by quantum chemical calculations to determine the protonation site in the ground electronic state (S0) and ππ(*) excited state (S1) as a function of microhydration. IR spectra of [BZ-(H2O)n]H(+) with n ≤ 2 are consistent with BZH(+)-(H2O)n type structures, in which the excess proton is localized on benzaldehyde. IR spectra of clusters with n ≥ 3 are assigned to structures, in which the excess proton is located on the (H2O)n solvent moiety, BZ-(H2O)nH(+). Quantum chemical calculations at the B3LYP, MP2, and ri-CC2 levels support the conclusion of proton transfer from BZH(+) to the solvent moiety in the S0 state for hydration sizes larger than the critical value nc = 3. The vibronic spectrum of the S1 ← S0 transition (ππ(*)) of the n = 1 cluster is consistent with a cis-BZH(+)-H2O structure in both electronic states. The large blueshift of the S1 origin by 2106 cm(-1) upon hydration with a single H2O ligand indicates that the proton affinity of BZ is substantially increased upon S1 excitation, thus strongly destabilizing the hydrogen bond to the solvent. The adiabatic S1 excitation energy and vibronic structure calculated at the ri-CC2/aug-cc-pVDZ level agrees well with the measured spectrum, supporting the notion of a cis-BZH(+)-H2O geometry. The doubly hydrated species, cis-BZH(+)-(H2O)2, does not absorb in the spectral range of 23 000-27 400 cm(-1), because of the additional large blueshift of the ππ(*) transition upon attachment of the second H2O molecule. Calculations predict roughly linear and large incremental blueshifts for the ππ(*) transition in [BZ-(H2O)n]H(+) as a function of n. In the size range n ≥ 3, the calculations predict a proton transfer from the (H2O)nH(+) solvent back to the BZ solute upon electronic ππ(*) excitation.

  9. Electronic and vibrational spectra of protonated benzaldehyde-water clusters, [BZ-(H2O)n≤5]H+: Evidence for ground-state proton transfer to solvent for n ≥ 3

    Science.gov (United States)

    Dopfer, Otto; Patzer, Alexander; Chakraborty, Shamik; Alata, Ivan; Omidyan, Reza; Broquier, Michel; Dedonder, Claude; Jouvet, Christophe

    2014-03-01

    Vibrational and electronic photodissociation spectra of mass-selected protonated benzaldehyde-(water)n clusters, [BZ-(H2O)n]H+ with n ≤ 5, are analyzed by quantum chemical calculations to determine the protonation site in the ground electronic state (S0) and ππ* excited state (S1) as a function of microhydration. IR spectra of [BZ-(H2O)n]H+ with n ≤ 2 are consistent with BZH+-(H2O)n type structures, in which the excess proton is localized on benzaldehyde. IR spectra of clusters with n ≥ 3 are assigned to structures, in which the excess proton is located on the (H2O)n solvent moiety, BZ-(H2O)nH+. Quantum chemical calculations at the B3LYP, MP2, and ri-CC2 levels support the conclusion of proton transfer from BZH+ to the solvent moiety in the S0 state for hydration sizes larger than the critical value nc = 3. The vibronic spectrum of the S1 ← S0 transition (ππ*) of the n = 1 cluster is consistent with a cis-BZH+-H2O structure in both electronic states. The large blueshift of the S1 origin by 2106 cm-1 upon hydration with a single H2O ligand indicates that the proton affinity of BZ is substantially increased upon S1 excitation, thus strongly destabilizing the hydrogen bond to the solvent. The adiabatic S1 excitation energy and vibronic structure calculated at the ri-CC2/aug-cc-pVDZ level agrees well with the measured spectrum, supporting the notion of a cis-BZH+-H2O geometry. The doubly hydrated species, cis-BZH+-(H2O)2, does not absorb in the spectral range of 23 000-27 400 cm-1, because of the additional large blueshift of the ππ* transition upon attachment of the second H2O molecule. Calculations predict roughly linear and large incremental blueshifts for the ππ* transition in [BZ-(H2O)n]H+ as a function of n. In the size range n ≥ 3, the calculations predict a proton transfer from the (H2O)nH+ solvent back to the BZ solute upon electronic ππ* excitation.

  10. Matematica Natural.

    Science.gov (United States)

    Lozano, Patricia; Medearis, Linda

    Matematica Natural (Natural Mathematics) is a mathematics curriculum for young children based on the assumption that they learn mathematics through concrete, real life, relevant experiences and that educational differences rather than cultural differences influence math achievement. The curriculum uses hands-on materials and activities to teach…

  11. Natur formet

    DEFF Research Database (Denmark)

    Søberg, Martin

    2011-01-01

    Anmeldelse af Malene Hauxner, "Fra naturlig natur til SUPERNATUR – Europæisk landskabsarkitektur 1967-2007 set fra Danmark", Risskov: Ikaros Press, 2011.......Anmeldelse af Malene Hauxner, "Fra naturlig natur til SUPERNATUR – Europæisk landskabsarkitektur 1967-2007 set fra Danmark", Risskov: Ikaros Press, 2011....

  12. Nature Detectives

    Science.gov (United States)

    Harr, Natalie; Lee, Richard E.; Jr.

    2010-01-01

    Richard Louv's "Last Child in the Woods" (2008) added to a growing consensus to get children outside and experiencing nature. Using ideas from place-based education, the authors present a simple year-long project that brings science, nature, and other curriculum standards to life right in your school yard. With a focus on journaling, this project…

  13. Matematica Natural.

    Science.gov (United States)

    Lozano, Patricia; Medearis, Linda

    Matematica Natural (Natural Mathematics) is a mathematics curriculum for young children based on the assumption that they learn mathematics through concrete, real life, relevant experiences and that educational differences rather than cultural differences influence math achievement. The curriculum uses hands-on materials and activities to teach…

  14. Nature Detectives

    Science.gov (United States)

    Harr, Natalie; Lee, Richard E.; Jr.

    2010-01-01

    Richard Louv's "Last Child in the Woods" (2008) added to a growing consensus to get children outside and experiencing nature. Using ideas from place-based education, the authors present a simple year-long project that brings science, nature, and other curriculum standards to life right in your school yard. With a focus on journaling, this project…

  15. Natural death.

    Science.gov (United States)

    Oehmichen, M; Meissner, C

    2000-01-01

    The increasing age of every human being is the beginning of the end of life, an obviously natural process, but any attempt to define the term 'natural death' soon encounters difficulties in defining what is meant by 'natural'. In the industrialized countries of the West, for example 'natural death' is thought of as the opposite of non-natural types of death such as accidental death, suicide, and homicide. The aim of our present survey is to discuss the meaning of the term 'natural death' under a clinical, a forensic and a scientific point of view with regard to recent developments especially in molecular biology. If there are 'external' physical influences, a medical-technical manipulation, a therapeutic or molecular biological intervention cannot be definitely ruled out as the cause of death, then use of the term 'natural death' in general is open to question. It will only remain meaningful if it can be applied with a specific meaning in definite practical situations. Current research and medical technology, however, do not allow use of the term 'natural death' in its conventional sense: it can thus be stricken from the medical vocabulary. Copyright 2000 S. Karger AG, Basel

  16. Dissonant Nature

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel

    2013-01-01

    Nature restoration is far from being a neural undertaking. Just like any other type of heritage production it can be the source of dissonance – ‘our’ nature is not necessary ‘their’ nature. Often this dissonance is managed in ways, which are not particular sensitive to site......-specificity. As exemplified by the Skjern River Restoration Project (1999-2003), one interpretation of the landscape sometimes suppresses other valid interpretations neglecting its diverse history. Landscape architecture might, however, provide an alternative approach to nature restoration that is more site specific...... and allows for multiple interpretations to coexist. Evidence can be found in the Re-naturalization of River Aire (2002-2015), a restoration project, which reveals approaches that could be labelled landscape architecture specific....

  17. Extreme Weather and Natural Disasters

    CERN Document Server

    Healey, Justin

    2012-01-01

    Australia is a vast land in which weather varies significantly in different parts of the continent. Recent extreme weather events in Australia, such as the Queensland floods and Victorian bushfires, are brutal reminders of nature's devastating power. Is global warming increasing the rate of natural disasters? What part do La Niña and El Niño play in the extreme weather cycle? Cyclones, floods, severe storms, bushfires, landslides, earthquakes, tsunamis - what are the natural and man-made causes of these phenomena, how predictable are they, and how prepared are we for the impacts of natural dis

  18. Synthesis, spectroscopic, physicochemical properties and binding site analysis of 4-(1H-phenanthro[9,10-d]-imidazol-2-yl)-benzaldehyde fluorescent probe for imaging in cell biology: Experimental and theoretical study.

    Science.gov (United States)

    Krawczyk, Przemysław; Jędrzejewska, Beata; Pietrzak, Marek; Janek, Tomasz

    2016-11-01

    In this study, the 4-(1H-phenanthro[9,10-d]-imidazol-2-yl)-benzaldehyde (PB1) was investigated as a fluorescent dye. For this reason, the spectroscopic properties in different solvents were thoroughly studied. The experimental data were supported by quantum-chemical calculations using density functional theory. Measurements and theoretical calculations showed that PB1 dye is characterized by the non-monotonic solvatochromism, strongly polar charge transfer excited state, large Stokes' shift, high fluorescence quantum yield and high fluorescence lifetime. Simulations using AutoDock presented in this study, showed that after conjugation with Concanavalin A in the active site with LYS116, the PB1 possesses the highest probability of binding affinity. The interaction between the PB1 dye and the Concanavalin A lectin has been investigated by circular dichroism spectroscopy. Conventional fluorescence microscopy imaging of Candida albicans and Yarrowia lipolytica cells, incubated with the PB1-Concanavalin A, was demonstrated. Results show that the PB1 dye is a photostable low molecular weight fluorescent probe, which emits a blue fluorescence. The results of this study have implications for designing PB1-protein conjugate as a valuable alternative to commercial probes designed for cellular labeling in biological and biomedical research. Calculated LogP value together with LogBCF show that PB1-protein conjugate is a valuable alternative to commercial probes designed for cellular labeling in biological and biomedical research. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. 5-Bromo-2-hydroxy-4-methyl-benzaldehyde inhibited LPS-induced production of pro-inflammatory mediators through the inactivation of ERK, p38, and NF-κB pathways in RAW 264.7 macrophages.

    Science.gov (United States)

    Kim, Kil-Nam; Ko, Seok-Chun; Ye, Bo-Ram; Kim, Min-Sun; Kim, Junseong; Ko, Eun-Yi; Cho, Su-Hyeon; Kim, Daekyung; Heo, Soo-Jin; Jung, Won-Kyo

    2016-10-25

    The aim of the present study was to investigate the effects of 5-bromo-2-hydroxy-4-methyl-benzaldehyde (BHMB) on inflammatory responses to lipopolysaccharide (LPS) in RAW 264.7 cells and the associated mechanism of action. BHMB concentration-dependently suppressed protein and mRNA expressions of iNOS and COX-2, thereby inhibiting the production of NO and PGE2 in LPS-stimulated RAW 264.7 cells. BHMB also reduced the mRNA expression of TNF-α, IL-6, and IL-1β in LPS-stimulated RAW 264.7 cells. To elucidate the mechanism underlying the anti-inflammatory activity of BHMB, we investigated the effects of BHMB on the mitogen-activated protein kinase and nuclear factor-kappa B (NF-κB) pathways. BHMB suppressed the phosphorylation and degradation of IκB-α and markedly inhibited the nuclear translocation of p65 and p50 in LPS-stimulated RAW 264.7 cells. The compound also inhibited the LPS-stimulated phosphorylation of ERK and p38. Taken together, these results illustrated that BHMB suppresses pro-inflammatory mediator and cytokine expression in LPS-stimulated RAW 264.7 cells by inhibiting the phosphorylation of ERK and p38 and the activation of NF-κB.

  20. The mechanism of the formation of the hemiaminal and Schiff base from the benzaldehyde and triazole studied by means of the topological analysis of electron localisation function and catastrophe theory

    Science.gov (United States)

    Berski, Slawomir; Zbigniew Ciunik, Leszek

    2015-04-01

    The mechanisms of reaction of benzaldehyde (ald) with 4-amine-4H-1,2,4-triazole (4at), leading to Schiff base (Sch) and water, were investigated using topological analysis of the electron localisation function and catastrophe theory. Two reactions (synthesis of hemiaminal and synthesis of Schiff base) are represented by one catastrophe sequence: ald+4at: 1-14-[FF†F†FFTS1FF†F†FF†F†CF†]-2-9-[C†FFTS3F†F†FFF]-0:Sch+H2O with only fold (F) and cusp (C) catastrophes. The first reaction, in which a molecule of the hemiaminal is formed, consists of 14 steps separated by 13 catastrophes. The mechanism is non-concerted. The covalent bond C-N is formed after the formation of the O-H bond is terminated. The Schiff base formation through the water molecule elimination in the second reaction requires nine steps with eight catastrophes. The mechanism is non-concerted because first the C-O bond is broken and then the proton transfer occurs that results in the O-H bond creation.

  1. Natural Communities

    Data.gov (United States)

    Kansas Data Access and Support Center — This dataset shows the locations of known tracts of high quality natural communities in Kansas, generalized to the PLSS section. It is not a compehensive dataset of...

  2. Natural Propositions

    DEFF Research Database (Denmark)

    Stjernfelt, Frederik

    Preface -- Introduction -- The generality of signs -- Dicisigns -- Some consequences of the dicisign doctrine -- Dicisigns and cognition -- Natural propositions--the evolution of semiotic self-control -- Dicisigns beyond language -- Operational and optimal iconicity in Peirce's diagrammatology...

  3. Writing Nature

    Directory of Open Access Journals (Sweden)

    Kristin Asdal

    2014-06-01

    Full Text Available This special issue of the Nordic Journal of Science and Technology Studies is interested in how nature, in different versions and forms, is invited into our studies, analyses, and stories. How is it that we “write nature”? How is it that we provide space for, and actually describe the actors, agents, or surroundings, in our stories and analyses? The articles in the issue each deal with different understandings of both the practices of writing and the introduction of various natures into these. In this introduction to the issue the editors engage with actor-network theory as a material semiotic resource for writing nature. We propose to foreground actor-network theory as a writing tool, at the expense of actor-network theory as a distinct vocabulary. In doing this and pointing out the semiotic origins to material-semiotics we also want to problematize a clear-cut material approach to writing nature.

  4. Natural Propositions

    DEFF Research Database (Denmark)

    Stjernfelt, Frederik

    Preface -- Introduction -- The generality of signs -- Dicisigns -- Some consequences of the dicisign doctrine -- Dicisigns and cognition -- Natural propositions--the evolution of semiotic self-control -- Dicisigns beyond language -- Operational and optimal iconicity in Peirce's diagrammatology...

  5. Preparing for Surgery

    Science.gov (United States)

    ... Events Advocacy For Patients About ACOG Preparing for Surgery Home For Patients Search FAQs Preparing for Surgery ... Surgery FAQ080, August 2011 PDF Format Preparing for Surgery Gynecologic Problems What is the difference between outpatient ...

  6. Preparing for Surgery

    Science.gov (United States)

    ... Events Advocacy For Patients About ACOG Preparing for Surgery Home For Patients Search FAQs Preparing for Surgery ... Surgery FAQ080, August 2011 PDF Format Preparing for Surgery Gynecologic Problems What is the difference between outpatient ...

  7. Preparation and preliminary biological evaluation of [[sup 18]F]NCQ-115: a new selective reversible dopamine D2 receptor ligand

    Energy Technology Data Exchange (ETDEWEB)

    Najafi, A.; Peterson, A.; Buchsbaum, M. (California Univ., Irvine, CA (United States). Dept. of Psychiatry); O' Dell, S.; Weihmuller, F. (California Univ., Irvine , CA (United States). Dept. of Psychobiology)

    1993-05-01

    [sup 18]F-labeled dopamine D2 antagonist, NCQ-115 ((+)-(R)-5-bromo-N-((fluorobenzyl)-2-pyrrolidinyl)-methyl-2,3-dime thoxybenzamide), was successfully prepared using a remotely controlled system. [[sup 18]F]Fluoride was reacted with the trifluoromethanesulfonate salt of 4-(trimethylamino)benzaldehyde. The product was first reduced with LAH, and then reacted with thionyl bromide to yield [sup 18]F-labeled 4-fluorobenzylbromide. [[sup 18]F]4-fluorobenzylbromide was then reacted with the pyrrolidine precursor (NCQ-282) to yield the product [[sup 18]F]NCQ-115 contaminated with unreacted starting material. The product was purified by reverse phase chromatography yielding [[sup 18]F]NCQ-115 with a specific activity of more than 1400 Ci/mmol. Autoradiographic and biodistribution data following injection of [[sup 18]F]NCQ-115 in rats revealed the regional uptake of striatum/cerebellum to be 3.2 at 30 min post-injection. (author).

  8. Calcination temperature effect on catalytic properties of Cr{sub 2} O{sub 3}/Al{sub 2} O{sub 3} aerogel: mild oxidation of toluene to benzaldehyde; Effet de la temperature de calcination sur les proprietes catalytiques de l`aerogel Cr{sub 2}O{sub 3}-AI{sub 2}O{sub 3}: oxydation menagee du toluene en benzaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Younes, M.K.; Ghorbel, A. [Faculte des Sciences de Tunis, (Tunisia); Naccache, C. [Centre National de la Recherche Scientifique (CNRS), 69 - Villeurbanne (France). Inst. de Recherches sur la Catalyse

    1997-11-01

    The aerogel catalyst Cr{sub 2}O{sub 3}-Al{sub 2}O{sub 3}(Cr/Al = 0,05) presents a high specific surface area and an amorphous structure. The beneficial role of alumina when it is added to chromia, is related to the stabilisation of both low coordinated Cr{sup 3+} and highly oxidized Cr{sup 5+} ions. A small change of the surface state is observed under heating treatment for temperature below 700 deg C. Above this temperature the surface structure changes. The Cr{sup 3+} ions are favoured and the majority of them remains on the catalyst surface as Cr{sub 2}O{sub 3} aggregates. The other part of chromium ions seems to be inserted in the alumina network. The effect of calcination is to decrease the catalytic activities of formation of all the products obtained in the toluene oxidation reaction and improves the benzaldehyde selectivity. (authors) 18 refs.

  9. 沼气提纯制取生物天然气发展前景分析%Discussion on the Prospects of Bio-natural Gas Preparation by Methane Purification

    Institute of Scientific and Technical Information of China (English)

    方鸽

    2015-01-01

    In recent years,based on the consideration of both the energy and environmental issues,biomass ener⁃gy and other renewable energy have attracted great attention. As a new type of renewable energy,bio-natural gas purified from methane has huge commercial value,and development and utilization of which is in line with na⁃tional industrial policy and the prospect is broad. This paper describes the necessity and feasibility of the develop⁃ment of bio-natural gas purification technology from methane,and introduces the basic situation and application cases of domestic purification technology of methane,and gives the prospects of the project.%近年来,出于对能源问题和环境问题的双重思考,生物质能等可再生能源引起极大关注。沼气提纯制取生物天然气作为一种新型可再生能源,开发利用符合国家产业政策,商业价值巨大,开发利用前景广阔。本文阐述了发展沼气提纯制取生物天然气技术的必要性和可行性,并介绍了国内沼气提纯技术的基本情况和应用案例,对该项目的发展前景做出展望。

  10. Naturalness redux

    CERN Document Server

    Fabbrichesi, Marco

    2015-01-01

    The idea of naturalness, as originally conceived, refers only to the finite renormalization of the Higgs boson mass induced by the introduction of heavier states. In this respect, naturalness is still a powerful heuristic principle in model building beyond the standard model whenever new massive states are coupled to the Higgs field. The most compelling case is provided by the generation of neutrino masses. In this paper we confront this problem from a new perspective. The right-handed sector responsible for the seesaw mechanism---which introduces a large energy threshold above the electroweak scale---is made supersymmetric to comply with naturalness while the standard model is left unchanged and non-supersymmetric. Cancellations necessary to the naturalness requirement break down only at two loops, thus offering the possibility to increase the right-handed neutrino mass scale up to one order of magnitude above the usual values allowed by naturalness. If also the weak boson sector of the standard model is mad...

  11. Emancipating Nature

    DEFF Research Database (Denmark)

    Munk, Anders Kristian

    2012-01-01

    The issue of riverine flooding in the UK is closely tied up with computer simulations. Arguably, these modelling practices are ripe with the anticipation of nature. They aspire to pre-empt it, hence expect it to be ‘out there’, and ultimately work through formalized distillations of it – hydrodyn......The issue of riverine flooding in the UK is closely tied up with computer simulations. Arguably, these modelling practices are ripe with the anticipation of nature. They aspire to pre-empt it, hence expect it to be ‘out there’, and ultimately work through formalized distillations...... of it – hydrodynamic equations – which have their own anticipations and place their own demands on their modellers. Through the experience of a flood modelling apprenticeship I argue that the taking-place of such anticipations paradoxically relies on the birth of a hybrid, the model-modeller, and thus on a nature...

  12. Ley Natural

    OpenAIRE

    2010-01-01

    1. La expresión «ley natural» en la historia de las ideas. Uso ético y uso científico. 2. La cuestión de las leyes naturales en el ámbito de la naturaleza y en el ámbito de la conducta humana. 3. La ley natural como teoría moral se desarrolla en dos planos: a) plano práctico: el obrar humano responde a razones, depende de principios que constituyen una única ley; b) plano de fundamentación metafísica: la ley natural como participación de la ley eterna en la criatura racional. 4. La ley nat...

  13. Emancipating Nature

    DEFF Research Database (Denmark)

    Munk, Anders Kristian

    2012-01-01

    The issue of riverine flooding in the UK is closely tied up with computer simulations. Arguably, these modelling practices are ripe with the anticipation of nature. They aspire to pre-empt it, hence expect it to be ‘out there’, and ultimately work through formalized distillations of it – hydrodyn......The issue of riverine flooding in the UK is closely tied up with computer simulations. Arguably, these modelling practices are ripe with the anticipation of nature. They aspire to pre-empt it, hence expect it to be ‘out there’, and ultimately work through formalized distillations...... of it – hydrodynamic equations – which have their own anticipations and place their own demands on their modellers. Through the experience of a flood modelling apprenticeship I argue that the taking-place of such anticipations paradoxically relies on the birth of a hybrid, the model-modeller, and thus on a nature...

  14. Natural games

    CERN Document Server

    Anttila, Jani

    2011-01-01

    Behavior in the context of game theory is described as a natural process that follows the 2nd law of thermodynamics. The rate of entropy increase as the payoff function is derived from statistical physics of open systems. The thermodynamic formalism relates everything in terms of energy and describes various ways to consume free energy. This allows us to associate game theoretical models of behavior to physical reality. Ultimately behavior is viewed as a physical process where flows of energy naturally select ways to consume free energy as soon as possible. This natural process is, according to the profound thermodynamic principle, equivalent to entropy increase in the least time. However, the physical portrayal of behavior does not imply determinism. On the contrary, evolutionary equation for open systems reveals that when there are three or more degrees of freedom for behavior, the course of a game is inherently unpredictable in detail because each move affects motives of moves in the future. Eventually, wh...

  15. Towards a full understanding of the nature of Ni(II) species and hydroxyl groups over highly siliceous HZSM-5 zeolite supported nickel catalysts prepared by a deposition-precipitation method.

    Science.gov (United States)

    Chen, Bao-Hui; Chao, Zi-Sheng; He, Hao; Huang, Chen; Liu, Ya-Juan; Yi, Wen-Jun; Wei, Xue-Ling; An, Jun-Fang

    2016-02-14

    Highly siliceous HZSM-5 zeolite supported nickel catalysts prepared by a deposition-precipitation (D-P) method were characterized by Fourier transform infrared (FT-IR), hydrogen temperature programmed reduction (H2-TPR), X-ray diffraction (XRD), N2-absorption/desorption, field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), and (27)Al magic-angle nuclear magnetic resonance (MAS NMR) techniques. The results showed that the D-P of nickel species occurred predominantly on the internal surface of highly siliceous HZSM-5 zeolite, in which the internal silanol groups located on the hydroxylated mesopores or nanocavities played a key role. During the D-P process, nickel hydroxide was first deposited-precipitated via olation/polymerization of neutral hydroxoaqua nickel species over the HZSM-5 zeolite. With the progress of the D-P process, 1 : 1 nickel phyllosilicate was formed over the HZSM-5 via the hetero-condensation/polymerization between charged hydroxoaqua nickel species and monomer silicic species generated due to the partial dissolution of the HZSM-5 framework. The 1 : 1 nickel phyllosilicate could also be generated via the hydrolytic adsorption of hydroxoaqua nickel species and their subsequent olation condensation. After calcination, the deposited-precipitated nickel hydroxide was decomposed into nickel oxide, while the 1 : 1 nickel phyllosilicate was transformed into 2 : 1 nickel phyllosilicate. According to the above mechanism, Ni(ii) species were present both in the form of nickel oxide and 2 : 1 nickel phyllosilicate, which were mutually separated from each other, being highly dispersed over HZSM-5 zeolite.

  16. 天然迎春花提取液作为抑菌成分洗手液的制备%The Preparation of Hand Sanitizer with Natural Jasminum Nudiflorum Extracting Solution as Antibacterial Components

    Institute of Scientific and Technical Information of China (English)

    王书红; 杜慧; 张换平; 田大勇; 高战胜; 赵密柱; 李安林

    2015-01-01

    采用迎春花提取液作为杀菌抑菌剂,用十二烷基硫酸钠和乙氧基化烷基硫酸钠作为表面去污活性成分,丙三醇和三乙酸甘油酯作为保湿剂,柠檬酸-柠檬酸钠缓冲液作为pH调节剂,制备了一种新型的洗手液。对洗手液进行了性能检测,结果与国家洗手液标准相比较,总活性物含量、泡沫高度、粘度、重金属含量等指标均符合或优于国家洗手液标准。同时对洗手液的抑菌性能进行了检测,结果说明洗手液的抑菌性能良好。%With Jasminum nudiflorum extracting solution as antisepsis agents, lauryl sodium sulfate and Sodium ethoxylated alkyl sulfate as surface decontamination active ingredients, glycerol and triacetin as humectants, citric acid and sodium citrate as pH modifiers, a new type hand sanitizer was prepared.The performances of the hand sanitizer were tested.The results showed that compared with hand sanitizer standards of the state, the total content of active matter, foam height, viscosity and content of heavy metal comply with the standard, or even higher than the standard of the state.Meanwhile, the antibacterial performance of the hand sanitizer was tested.The result showed that it was good.

  17. 冻融循环制备天然水溶性甲壳素及其特性%Preparation and characterization of natural water-soluble-chitin using freezing-thawing-cylic treatment

    Institute of Scientific and Technical Information of China (English)

    刘廷国; 查萍萍; 杨凌霄; 李斌

    2011-01-01

    Partially deacetylated chitin with different degree of deacetylation (DDA) were prepared by alkaline treatment under homogeneous conditions using freezing-thawing-cyclic treatment. The water solubility (WS) and DDA was determined and the influence of DDA, crystalline index (Xc) and the hydrogen bonding interaction were investigated by Fourier transform infared spectroscory (FT-IR),differential scanning calorimenty (DSC) and X-ray diffraction (XRD). There was a close relationship between solubility and crystal structure and crystallinity. The analysis shows that there was no essential difference between the water-soluble-chitin (WSC) and commercial chitosan, being a surely native water soluble chitin.%利用冻融循环处理制备甲壳素均相溶液,在温和的均相条件下脱乙酰化制备了不同脱乙酰度的天然水溶性甲壳素,并测定了样品的水溶性和脱乙酰度.利用X-射线衍射(XRD)、傅里叶红外光谱(FT-IR)和差示扫描量热法(DSC)研究了样品的结晶指数和氢键相互作用与样品水溶性和脱乙酰度之间的关系.结果表明:样品的水溶性与结晶结构和结晶度关系密切;样品与商品壳聚糖没有本质差异,是一种真正的天然水溶性甲壳素.

  18. [Natural selection].

    Science.gov (United States)

    Mayr, E

    1985-05-01

    Much of the resistance against Darwin's theory of natural selection has been due to misunderstandings. It is shown that natural selection is not a tautology and that it is a two-step process. The first step, the production of variation, is under the control of chance; the second step, selection proper, is an anti-chance process, but subject to many constraints. The target of selection is the individual as a whole, and many neutral mutations can be retained as hitchhikers of successful genotypes. Sexual selection results from selection for pure reproductive success.

  19. Provincialising Nature

    DEFF Research Database (Denmark)

    Provincialising Nature: Multidisciplinary Approaches to the Politics of the Environment in Latin America offers a timely analysis of some of the crucial challenges, contradictions and promises within current environmental discourses and practices in the region. This book shows both challenging...... scenarios and original perspectives that have emerged in Latin America in relation to the globally urgent issues of climate change and the environmental crisis. Two interconnected analytical frameworks guide the discussions in the book: the relationship between nature, knowledge and identity and their role...

  20. Kritikkens natur

    DEFF Research Database (Denmark)

    Schatz-Jakobsen, Claus

    1999-01-01

    Artiklen introducerer det nye forskningsfelt inden for samtænkning af litteratur, kultur og natur, den såkaldt økologiske kritik, og kaster et kritisk blik på  dens brug af romantisk litteratur som proto-økologisk kanon.......Artiklen introducerer det nye forskningsfelt inden for samtænkning af litteratur, kultur og natur, den såkaldt økologiske kritik, og kaster et kritisk blik på  dens brug af romantisk litteratur som proto-økologisk kanon....